|Exam Name||:||Implementation of DP Solutions for Windows using NBU 5.0|
|Questions and Answers||:||114 Q & A|
|Updated On||:||February 22, 2019|
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250-722 exam Dumps Source : Implementation of DP Solutions for Windows using NBU 5.0
Test Code : 250-722
Test Name : Implementation of DP Solutions for Windows using NBU 5.0
Vendor Name : Symantec
Q&A : 114 Real Questions
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• howdy Andrey tell us more in aspect what is the peculiarity of your career?
• hi, the scope of consulting is extremely large and infrequently requires going beyond the normal action algorithms. My adventure is in a variety of company areas, from the corporation of grain exports to the outlet of the Nano centre. by means of the character of my expert undertaking, I should resolve a huge variety of problems of my consumers, hence, I believe it is more relevant to call my distinctiveness not simply a consultant, but reasonably a project manager.
• So, the main direction of your business pastime is undertaking administration?
• it is correct! tasks, as already outlined above, there have been many and they're all distinctive. different areas, as, for instance, within the coverage enterprise "Russia", the main project was the building and increase of business capitalization. The outcome of our work was the entry into the accurate 10 of the largest insurance enterprise's in Russia, and the capitalization of the enterprise increased by using 12 instances. it's also anti-disaster management - for instance, the implementation of the rescue plan of the construction keeping "Monolith maintaining" - the largest from the Urals to Kamchatka, found in the metropolis of Krasnoyarsk. Our team coped with the project and the most advantageous affirmation of this is that the protecting turned into a hit 10 years later.
• With which course is it greater at ease to be just right for you - "task" or "anti-disaster"?
• or not it's a difficult query. With crisis administration, there's always loads of negativity. The adoption of "unpopular decisions", the discount of body of workers and wages - is inevitable.
it is quite another element when a team moves a company ahead to new horizons. you're employed the equal 12-15 hours, however choices are already made not about a way to make discount rates, but about the place to discover personnel to support boost the business.
hence, if we talk about consolation, then - each person wants to work and convey joy to the whole crew, and never a part of the survivors. but in terms of adventure - each undertaking is wonderful.
• to your profiles in social networks, you are talking a couple of project involving greater than 5,000 individuals, about saving a big systemically vital enterprise for a region, do you suggest the implementation of an anti-crisis plan for Monolith protecting? may you inform us greater about this?
• sure. lamentably, as a result of the disaster, the building market in 2008-2009 skilled a pointy drop in condo sales, which affected Monolith conserving, given that it assumed all responsibilities below a very different market circumstance.
We first carried out due diligence, proposed an anti-crisis plan. At a joint assembly accepted, and that i all started to put in force it. and then it became tough 6 months.
We created a management enterprise, centralized economic administration, introduced a treasury agreement mode, when all payments of the conserving went via a single treasury. They performed a few adjustments geared toward optimizing the feature of constructing handle, created a gadget for featuring planned and manage reporting, with a view to increase the transparency of the burden on the keeping prison entities ...
• You saved the enterprise, but weren't these movements similar to the behaviour of the infamous Elah chainsaws? How can you in the reduction of such a few personnel, despite the fact that it's to shop a company?
• Wow, I wish to answer, of path, how fantastic it turned into and the way all and sundry unanimously skilled the vital hardships. The truth, regrettably, is different.
When the plan turned into implemented, a whole lot of unpopular decisions have been taken, greater than 1,000 individuals were decreased or retired.
it's now not well-nigh saving the company - we've saved about three,000 jobs via huge efforts. here is the result.
• so far as i know, during the past you had been the pinnacle of Euro Commerce bank, which showed the maximum growth among all retail lending associations outdoor of the precise 30. Many americans considered the leading aim of success to be the social orientation of capabilities, is that this no longer actual?
• As all the time, not every thing is fundamental and glaring, i might single out a couple of components that contributed to the success of this mission: a different product line, focus on poorly lined market niches and over-prompted team of authorities.
• Andrey, clarify in additional detail why they decided to advance the business in this particular course, did different banks then refuse from such an idea?
• See what the Banks are doing, and indeed most of the groups - they present to the market a provider it is less difficult to deliver, and the margin on which is better. Our crew decided to do otherwise. Our products required lots of work and gave a low salary from every particular person operation. It does not sound very optimistic, does it?
however here is precisely the element of growth. The banking sector believed that working with migrants is a job that will never pay for itself ... the base line is that within the small workplaces we reached a capability of 400-600 individuals a day for commission products. And this has already brought a major income. We made payments and transfers quicker than every other financial institution in the market, studied the ethnic composition in the territories and chose operating personnel who speak the same language with the customer (Uzbek, Tajik, and many others.).did you know at least one bank, the place even after 7 years there is a similar angle to the customer?
• good enough, so that you are for a gap enterprise?
- sure. Our 2nd of the main client companies is pensioners.These people desire realizing, empathy and solutions to their complications - which we offered in each office.personnel all the time welcomed purchasers with a kind word and provided a cup of sizzling tea in the wintry weather or a tumbler of cool water in the summertime.hence, those customer agencies that we concentrated on, cherished us, got here to our offices for all the functions, so the financial institution had a extremely decent profitability.on the equal time - if the client became the core type from the city of a million individuals, the bank would absolutely enter the excellent one hundred banks of Russia. • lamentably, towards the historical past of mass revocation of licenses from banks, the Eurokommerz license was additionally revoked, Has it affected your career?
- We built an excellent financial institution, within the fall of 2014 an inventive assignment with suitable 5 sellers of the country became in full swing. however the pursuits of December 15/16, 2014 have came about. The dollar and euro rose after the announcement of the significant bank of the Russian Federation to lift the discount rate to 17%. due to the fact the mission being launched concerned serious international capital involvement, it became frozen indefinitely. Then, in the spring of 2015, the shareholders decided to exit the banking enterprise, and i left the financial institution. and then, October 23, 2015 - the news in regards to the revocation of the license. Shock, emptiness, the feeling of dropping anything very shut, even though it did not work there at that time, however 5 years of complicated work! it's one thing when he labored in a challenge and he lives and prospers, an additional issue when, youngsters for explanations beyond your handle, the business doesn't turn into.neatly, as for my profession, i will say one issue: experience is worthwhile!
• What initiatives are you operating now?
• In 2012, I headquartered the consulting group "BusinessInvitee" and after the completion of the banking challenge I began to spend considerable time on the building of this company. among the many purchasers are famous sportsmen, the greatest private holdings. somebody wants a restructuring of property, a person needs a company valuation before a transaction, and somebody wants an asset valuation. initiatives are distinct and fascinating, with their personal specifics. there have been M & A deals, due diligence, auditing, theory development and implementation of the primary Russian network of fiscal supermarkets and an awful lot extra.
• What difficulties do you encounter most frequently?
• The hindrance for the building of the consulting company in Russia, oddly enough, are the businessmen themselves - there isn't any work lifestyle. company is much less acquainted with auditing and rating agencies, but consulting for almost all is like signing your personal lack of knowledge and shortage of professionalism. even though it is consulting structures that accumulate the realm's best practices and the most a success applied sciences for enterprise building and healing.
• What do you feel are the main explanations in your success?
• Of direction, devoid of perseverance, professionalism and difficult work, nothing will come out, no longer best in Consulting, but, possibly, in some other sphere. Of course, other characteristics are essential, however I accept as true with these to be essentially the most colossal. real, it is essential to be aware what is supposed by each of those words, and a lot of individuals call perseverance and hard work just the reality of being within the workplace for 12 hours.
• Does your family support you? still, the absence of a husband and father at domestic ...
- household helps. however, of route, i want to look me greater regularly.americans who are not liable, leading positions, believe that the bosses only receives a commission extra, however work less, or even lie all day on the seaside. however's no longer like that.existence example: Saturday evening, at about 11 pm and i am at a friend's wedding. The break is in full swing. And what do you feel I do? i'm attending the marriage - or not it's physically existing, as a result of at the present the assignment, which the crew and i had been engaged in for the last six months, reached the ultimate stage, or not it's important for Western companions to finish the deal particulars by using Sunday morning, that allows you to prepare press releases on Sunday Monday. in all probability this sounds fascinating should you do this as soon as every 10 years, and for those who always, of course, get drained.incidentally, in that night situation, as in the whole task, we labored to the proper 5 with a plus and outplayed within the negotiation system one of the optimum law businesses and one of the most largest audit and consulting groups on this planet.
• How do you check the latest economic circumstance?
- There are at all times aspects of growth, even within the most intricate situations. And as at all times, what's dangerous for one is first rate for others.In Russia, affordable labour. So exports should still grow.based on the new economic circumstance, the structure of imports is altering. What changed into imported prior is not any longer low-priced for the old classification of buyers, so now the rate transformation of demand is taking location, which in flip might be a lever for increase for importers who locate aggressive and low cost goods, and for exporters a chance to increase the degree of processing within the territory Russia and, accordingly, the margin, working with the exterior market.
• towards the heritage of the aggravation of foreign financial relations, are you attracted to any overseas tasks, do you see in them a point of view?
• Of route! i would say that it isn't international financial relations which are exacerbated, but overseas policy members of the family, which, in flip, put power on overseas economic family members. right here I consider the as soon as-heard evaluation: the legal guidelines of economics are just like the laws of physics, that you would be able to are attempting to violate them, however this will require a big expenditure of power and money, so one can become warmth, with a purpose to dissipate and should not carry any benefit to any individual. • What would you are looking to our readers?
I need to thanks to your attention and need to preserve the means to sensibly investigate each your personal energy and the state of the encircling world. in my view, here's a very essential skill in the realities of brand new truth.
- thanks, Kovalev Andrey Sergeevich, challenge manager, troubleshooter, crisis supervisor, who effectively achieved a few initiatives interesting to Russia, became with us.
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In our exploration of algorithms, we’ve applied many techniques to supply results. Some ideas have used iOS-particular patterns whereas others had been extra generalized. although it hasn’t been explicitly mentioned, a few of our options have used a specific programming vogue referred to as dynamic programming. whereas easy in conception, its utility can now and again be nuanced. When utilized accurately, dynamic programming can have an impressive impact on the way you to write code. during this essay, we’ll introduce the concept and implementation of dynamic programming.keep For Later
in case you’ve bought some thing via Amazon.com, you’ll be general with the web page term — “store For Later”. because the phrase implies, consumers are offered the choice so as to add objects to their cart or shop them to a “wish record” for later viewing. When writing algorithms, we often face a similar alternative of completing actions (performing computations) as information is being interpreted or storing the results for later use. Examples encompass retrieving JSON records from a RESTful provider or using the Core statistics Framework:
In iOS, design patterns can support us time and coordinate how statistics is processed. selected thoughts include multi-threaded operations (e.g. Grand imperative Dispatch), Notifications and Delegation. Dynamic programming (DP) having said that, isn’t always a single coding method, but quite how to think about moves (e.g. subproblems) that occur as a function operates. The ensuing DP answer might range counting on the issue. In its least difficult kind, dynamic programming relies on statistics storage and reuse to raise algorithm efficiency. The system of data reuse is often known as memoization and can take many kinds. As we’ll see, this trend of programming gives a lot of benefits.Fibonacci Revisited
in the essay on Recursion, we in comparison building the traditional sequence of Array values using each iterative and recursive recommendations. As mentioned, these algorithms had been designed to supply an Array sequence, no longer to calculate a specific result. Taking this into account, we are able to create a new version of Fibonacci to return a single Int cost:func fibRecursive(n: Int) -> Int if n == 0 return 0
if n <= 2 return 1
return fibRecursive(n: n-1) + fibRecursive(n: n-2)
firstly look, it seems this seemingly small feature would also be productive. youngsters, upon extra evaluation, we see a large number of recursive calls need to be made for it to calculate any effect. As shown below, on account that fibRecursive cannot save up to now calculated values, its recursive calls raise exponentially:Fibonacci Memoized
Let’s are trying a different technique. Designed as a nested Swift feature, fibMemoized captures the Array return value from its fibSequence sub-characteristic to calculate a ultimate value:extension Int
//memoized versionmutating func fibMemoized() -> Int
//builds array sequencefunc fibSequence(_ sequence: Array<Int> = [0, 1]) -> Array<Int>
var final = Array<Int>()
//mutated copyvar output = sequence
let i: Int = output.count
//set base situation - linear time O(n)if i == self return output
let outcomes: Int = output[i - 1] + output[i - 2]output.append(consequences)
//set iterationfinal = fibSequence(output)return final
//calculate closing product - consistent time O(1)let effects = fibSequence()let answer: Int = consequences[results.endIndex - 1] + results[results.endIndex - 2]return reply
notwithstanding fibSquence includes a recursive sequence, its base case depends upon the number of requested Array positions (n). In efficiency terms, we are saying fibSequence runs in linear time or O(n). This performance development is carried out by memoizing the Array sequence mandatory to calculate the last product. subsequently, each and every sequence permutation is computed as soon as. The benefit of this method is considered when evaluating both algorithms, shown under:Shortest Paths
Code memoization can additionally improve a program’s effectivity to the element of constructing reputedly intricate or virtually unsolvable questions answerable. An instance of this can be seen with Dijkstra’s Algorithm and Shortest Paths. To evaluate, we created a distinct statistics structure named direction with the purpose of storing selected traversal metadata://the direction type maintains objects that contain the "frontier" class route
var total: Intvar destination: Vertexvar previous: direction?//object initializationinit()vacation spot = Vertex()complete = 0
What makes course constructive is its skill to keep facts on nodes in the past visited. comparable to our revised Fibonacci algorithm, route outlets the cumulative edge weights all traversed vertices (complete) in addition to a complete historical past of each visited Vertex. Used simply, this permits the programmer to reply questions such as the complexity of navigating to a particular destination Vertex, if the traversal become indeed successful (in discovering the vacation spot), as neatly as the record of nodes visited throughout. counting on the Graph size and complexity, no longer having this assistance obtainable might suggest having the algorithm take so lengthy to (re)compute facts that it turns into too gradual to be positive, or now not being in a position to remedy essential questions because of insufficient records.
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Considerable attention has been given to progressive neurodegenerative diseases affecting the basal ganglia such as Parkinson’s disease (PD) and Huntington’s disease (HD). Both PD and HD are terminal neurodegenerative diseases that elicit a variety of motor and non-motor manifestations, which significantly contribute to decreased quality of life (Jankovic, 2008; Walker, 2007). As PD and HD affect different regions of the basal ganglia, the manifestations differ between both diseases. In PD, damage of dopaminergic neurons in the substantia nigra and related dopamine depletion lead to debilitating loss of movement due to muscle rigidity, bradykinesia and resting tremor. In HD, damage to the striatum primarily results in extensive semi-directed, non-rhythmic movements termed chorea, dementia and psychiatric manifestations encompassing behavioral difficulties connected with lower emotional control and intense irritability (Jankovic, 2008; Walker, 2007).
The majority of both PD and HD patients manifest the motor speech disorder termed dysarthria (Hartelius et al., 2003; Logemann et al., 1978; Rusz et al., 2014), which is an impairment resulting from sensorimotor abnormalities that may affect all subsystems of speech including respiration, phonation, articulation, prosody, and resonance (Duffy, 2013). The dysarthrias are differentiated according to perceptual characteristics of speech and corroborated by the underlying neuropathology. In particular, PD is associated with hypokinetic dysarthria due to akinesia and bradykinetic-rigid syndromes, whereas HD shows hyperkinetic dysarthria resulting from chorea (Duffy, 2013). Despite the fact that both PD and HD are primarily disorders of the basal ganglia, the distinctive speech patterns connected with hypokinetic and hyperkinetic dysarthria are usually antagonistic. For instance, hypokinetic dysarthria in PD typically shows reduced vocal loudness and flattened loudness and pitch inflections, poor voice quality, variable and frequently increased speech rate, inappropriate silences and breathiness, while in contrast hyperkinetic dysarthria in HD demonstrates excess loudness and pitch variations, voice arrests, slow speech rate, inappropriate vocal noises and intermittent breathy segments (Darley, Aronson & Brown, 1975; Logemann et al., 1978; Rusz et al., 2014).
Interestingly, although hypokinetic and hyperkinetic dysarthria manifestations are often counteractive, hypernasality has been reported in both hypokinetic and hyperkinetic dysarthria (Duffy, 2013; Hoodin & Gilbert, 1989; Chenery, Murdoch & Ingram, 1988; Logemann et al., 1978; Theodoros, Murdoch & Thompson, 1995). In particular, investigation of both PD and HD provides us with the unique possibility to study the effect of basal ganglia dysfunction on the presence of hypernasality. Admittedly, hypernasality represents a distinctive manifestation of certain dysarthria subtypes, particularly of flaccid dysarthria, and thus its evaluation can provide useful information in the differential diagnosis of dysarthrias (Duffy, 2013).
Hypernasality is a result of velopharyngeal impairment and may be defined as the presence of inappropriate air leakage through the nasal cavity during phonation (Warren, Dalston & Mayo, 1993). This leakage may result from abnormal velopharyngeal structure, which is termed velopharyngeal insufficiency (VPI), and is present in patients with cleft palate, palatal fistula, and patients that have undergone maxillectomy. Other mechanisms of hypernasality are distorted neuromuscular control of the levator veli palatini muscle and velopharyngeal seal, termed velopharyngeal incompetence (VIC), which includes patients with neurodegenerative diseases (Folkins, 1988). While abnormal velopharyngeal structure primarily leads to hypernasality, impaired neuromuscular control leading to dysarthria results in multiple speech distortions in which the particular effect of hypernasality may be less apparent to the listener due to the presence of other dysarthria manifestations. Thus, the majority of recent hypernasality research has been focused on VPI-induced hypernasality (Dickson, 1962; Kataoka et al., 1996; Lee, Ciocca & Whitehill, 2003; Maier et al., 2008; Yoshida et al., 2000), whereas only a few studies have investigated VIC hypernasality (Hoodin & Gilbert, 1989; Chenery, Murdoch & Ingram, 1988; Poole et al., 2015).
Studies examining hypernasality in PD have yielded controversial results. Logemann et al. (1978) perceptually detected hypernasality in only 10% of PD patients, whereas Chenery, Murdoch & Ingram (1988) and Theodoros, Murdoch & Thompson (1995) reported hypernasality in more than 30% of PD speakers. In addition, Ludlow & Basich (1983) included hypernasality among the 10 most distinctive perceptual features of PD, while Darley, Aronson & Brown (1975) did not find hypernasality to be a prominent feature of hypokinetic dysarthria. Considering HD speakers, to the best of our knowledge, no study has systematically examined hypernasality during hyperkinetic dysarthria, although Duffy (2013) reported intermittent hypernasality as one of the most deviant speech dimensions present in hyperkinetic dysarthria.
The etiology of hypernasality in PD and HD is unclear. Although the dysarthria is typically attributed to the disrupted motor control, little correspondence between speech and limb manifestations has been found (Schulz & Grant, 2000). Nevertheless, recent evidence based upon longitudinal follow-up data has shown that speech disorders in PD are generally related to the dopaminergic responsiveness of bradykinesia (Rusz et al., 2016). We may thus hypothesize that bradykinetic disturbances in soft palate control in PD may affect articulation of the velopharyngeal seal and accordingly lead to steady air leakage and increased hypernasality. Moreover, distorted neuromuscular control of levator veli palatini in PD may lead to increased hypernasality with increased fatigue during speech tasks.
In HD, the relationship between speech and limb manifestations appears to be more prominent. Correlation between speech timing parameters and overall motor disability has been noted previously (Rusz et al., 2014; Skodda et al., 2014). Furthermore, a relationship between laryngeal dysfunction and limb chorea has also been observed, likely as a result of laryngeal chorea (Rusz et al., 2013). Therefore, we hypothesize that choreatic movements of the velopharyngeal seal and velum may lead to varying resonance distortion, which would be in agreement with reported intermittent hyperkinetic dysarthria (Duffy, 2013).
Currently the most common method for hypernasality estimation is perceptual rating (Kuehn & Moller, 2000). In particular, perceptual assessment is considered the primary means to evaluate levels of nasality in children (Vogel et al., 2009). However, inter-rater and intra-rater reliability is questionable and perceptual rating requires a trained speech specialist (Kuehn & Moller, 2000). Consequently, more objective methods have been developed to complement perceptual ratings. Invasive methods, such as x-ray tracing with a lead pellet attached to the velum, provide direct observation of velopharyngeal movements (Hirose et al., 1981). Other methods employ indirect estimation based on measurements of nasal airflow, nasal cavity sonography, nasometry comparing nasal and oral acoustic outputs, or the Horii Oral-Nasal Coupling Index (Dillenschneider, Zaleski & Greiner, 1973; Hardin et al., 1992; Horii, 1980). One of the least demanding methods with respect to patients and equipment is the 1/3-octave spectra, which is based on direct, non-invasive analysis of acoustic speech signal and was originally developed for the estimation of velopharyngeal insufficiency in cleft palate (Kataoka et al., 1996) and was later validated by Vogel et al. (2009).
The 1/3-octave spectra method is a type of spectral analysis focused on the examination of spectral changes caused by resonatory speech pathologies. This method is based upon the linear source–filter theory of speech, which was first described by Fant (1960). According to this theory, speech is partly created by a transfer function of the vocal tract. The introduction of the nasal cavity to the vocal tract leads to significant changes in its transfer function by incorporating nasal resonance Fn at an area around 1 kHz (Stevens, 2000). Several previous studies have shown that nasal resonance is a reliable marker of hypernasality (Kataoka et al., 1996; Lee, Ciocca & Whitehill, 2003; Vogel et al., 2009; Yoshida et al., 2000). However, some vowels may mask nasal resonance by the presence of formant frequencies in the area close to 1 kHz.
The vowel /i/ with the first formant frequency (F1) at approximately 240 Hz and the second formant frequency (F2) at approximately 2,400 Hz appear to be the most sensitive to nasal resonance (Fant, 1960; Kataoka et al., 1996; Lee, Ciocca & Whitehill, 2003; Vogel et al., 2009). Being the most evident, nasal resonance in the vowel /i/ should be more robust to anatomical variation of the nasal cavity including asymmetrical shape and varying shape of the connected sinuses. Moreover, the vowel /i/ is considered to be the most sensitive to nasal coupling (Stevens, 2000), and thus previous studies have focused on the quantitative evaluation of VPI hypernasality through the sustained vowel /i/ (Kataoka et al., 1996; Lee, Ciocca & Whitehill, 2003; Yoshida et al., 2000). Based on experiments with experienced listeners and the rating of nasality in artificially generated sounds in patients with cleft palate and those that underwent maxillectomy, previous studies have confirmed the vowel /i/ as an ideal speech task for hypernasality assessment (Kataoka et al., 1996; Vogel et al., 2009; Yoshida et al., 2000). Moreover, limited motion of the articulators including the jaw, tongue and lips in dysarthrias co-occur with velopharyngeal inadequacy and may play a more dominant role in changing the measures related to nasality. From this perspective, prolongation of vowel /i/ is a particularly suitable task to acoustically assess nasality in dysarthrias, as it represents relatively steady vocal function without the confounding effects of articulatory components of running speech.
Based upon these previous findings, the goal of the present study was to employ methods of objective hypernasality assessment and evaluate the presence and character of hypernasality in PD and HD speakers. A further aim was to examine possible relationships between the severity of hypernasality and disease-specific motor manifestations, to provide more insight into the pathophysiology responsible for development of hypernasality in basal ganglia disorders.Methods Subjects
The participants in the present study were part of a larger investigation examining speech characteristics of patients with PD and HD. Previous reports generally focused on phonatory, articulatory and prosodic abnormalities including medication effects (Rusz et al., 2013; Rusz et al., 2014; Rusz et al., 2016). A total of 111 Czech native speakers, including 37 PD patients, 37 HD patients and 37 healthy participants were recorded.
The PD group consisted of 23 men and 14 women, mean age 63.1 ± 14.0 standard deviation (SD) (range 41–80) years, mean disease duration 8.0 ± 4.8 (1–24) years. All PD patients fulfilled the diagnostic criteria for PD (Hughes et al., 1992). All participants were on stable dopaminergic medication for at least 4 weeks before the examinations, which were conducted in the on-medication state. All PD patients underwent neurological examinations by an experienced neurologist and were rated according to the Hoehn & Yahr staging scale (H&Y, ranging from 1 to 5, where 1 indicates mild unilateral motor disorder and 5 indicates confinement to wheelchair or bed) and motor Unified Parkinson’s Disease Rating Scale (UPDRS III, ranging from 0 to 108, with 0 for no motor manifestation and 108 representing severe motor distortion) (Hoehn & Yahr, 1967; Stebbins & Goetz, 1998). In addition, the UPDRS composite subscore of bradykinesia (sum of UPDRS III items 23, 24, 25 and 26, ranging from 0 to 24, with 0 for no bradykinesia and 24 representing severe bradykinetic distortion) was estimated (Hughes et al., 1992; Jankovic, 2008). Perceptual speech evaluation was based upon UPDRS III speech item 18 (range 0–4, with 0 representing normal speech and 4 indicating unintelligible speech). The H&Y score was 2.1 ± 0.4 (1–3), UPDRS III score was 17.5 ± 8.2 (4–36), the UPDRS bradykinesia subscore was 7.8 ± 3.6 (2–17), and the UPDRS III speech item 18 score was 0.8 ± 0.6 (0–2).
The HD group consisted of 19 men and 18 women with genetically confirmed HD with mean age 49.1 ± SD 12.7 (23–67) years, mean disease duration 6.1 ± 3.4 (1–16) years, mean number of CAG triplets 44.7 ± 3.3 (40–53). Most of the patients (32/37) were treated with monotherapy or a combination of benzodiazepines, antipsychotics, amantadine and antidepressants. All HD patients underwent extensive examination by an experienced neurologist and were rated according to the Unified Huntington’s Disease Rating Scale (UHDRS, ranging from 0 to 124, where 0 indicates no motor disability and 124 indicates severe motor disability) (Huntington-Study-Group, 1996). In addition, the UHDRS chorea subscore was estimated (ranging from 0 to 28, where 0 indicates no motor disability and 28 indicates severe motor disability) (Rusz et al., 2013; Walker, 2007). Perceptual speech evaluation was based upon the UHDRS speech item (ranging from 0 to 4, where 0 indicates no disability and 4 indicates severe dysarthria). The UHDRS motor score was 25.7 ± 12.2 (3–54), the UHDRS chorea subscore was 8.6 ± 3.7 (0–14), and the UHDRS speech item was 0.8 ± 0.5 (0–2).
The healthy control (HC) group consisted of 23 men and 14 women, mean age of 63.1 ± 8.7 (41–77) years. None of the HC participants had a history of neurological or speech disorder. None of the HD, PD or HC subjects suffered from chronic obstructive pulmonary disease, respiratory tract infection, allergy, asthma, facial paresis, or other malady that could negatively influence participant speech performance.
The study was approved by the Ethics Committee of the General University Hospital in Prague, Czech Republic, and all participants provided written, informed consent.Speech data
All recordings took place in a quiet room with a low ambient noise level using a head-mounted condenser microphone (Beyer-dynamic Opus 55, Heilbronn, Germany) positioned approximately 5 cm from each subject’s mouth. The utterances were sampled at 48 kHz with 16 bit quantization. All the voice signals were obtained during single session conducted by a speech specialist, who asked participants to take a deep breath and perform sustained phonation of vowel /i/ at a comfortable loudness and pitch, as constant and long as possible. The measurement of sustained phonation was performed twice. The participants were also asked to provide freely spoken monologue on a given topic including family, work or interests, for at least two minutes. The both sustained phonation and monologue tasks were part of a comprehensive dysarthria test battery. No time limits were imposed during recording. The inclusion criteria were determined as the ability to sustain prolonged phonation for at least three seconds.Perceptual analysis
As connected speech is more demanding for velopharyngeal control, it is considered the most valid task for perceptual nasality estimation (Kuehn & Moller, 2000). The rating of nasality was based on speech material where the patient produced a monologue and performed by 10 raters including one speech-language pathologist, three clinicians and six acoustic speech specialists using a graded scale (0 = normal nasality, 1 = mild hypernasality, 2 = moderate hypernasality, 3 = severe hypernasality), based on The Great Ormond Street Speech Assessment ’98 (GOS.SP.ASS.’98) (Sell, Harding & Grunwell, 1999). All the raters were trained by the speech-language pathologist prior to perceptual assessment. The perceptual assessment was performed blindly on randomized data consisting of all three participant groups. The presentation of samples was self-paced and performed by each rater separately, and each speech sample could be repeated at the discretion of the listener. The final score was obtained for overall perceptual rating across all raters by the median value computed from all perceptual assessments in the group. The inter-rater and intra-rater variability was estimated using a two way random average intra-class correlation (ICC). Intra-rater reliability was based upon the second perceptual assessments performed by all raters with more than three months delay. During the second assessment, each rater scored 27 randomly selected phonations (24% of entire dataset) equally representing PD, HD and HC groups.Acoustic analysis
For the purposes of instrumental analysis, two recording parts equal to 10% of signal length were cut off from both the beginning and end of the vowel /i/ to avoid distortion by initial vocal fold adjustment and fatigue at the end of the utterance. The remaining signal was then resampled to 20 kHz, which lowered the computational complexity and preserved all useful information (Titze, 1994). The preprocessed signal was divided using a hamming 60 ms window with 55 ms overlap. Subsequently, each window was analyzed using a 1/3-octave spectra method.
The process of 1/3-octave spectra analysis based on the multirate filter bank presented by Couvreour (1998) is illustrated in Fig. 1. The three highest 1/3-octave frequency band filters were designed according to this method. For our purposes, the 3rd order IIR Butterworth filters were used and centered on octave frequencies of 2,500 Hz (passband from 2244.9 Hz to 2828.4 Hz), 3,150 Hz (passband from 2828.4 Hz to 3563.6 Hz), and 4,000 Hz (passband from 3563.6 Hz to 4489.8 Hz). After filtering, the highest components were removed from recording and the signal was then down-sampled by a factor of 2, i.e., sampling frequency (fs) to fs/2. Being defined in relation to the fs, the filter characteristics related to fs/2 yielded one octave lower for each down sampling. Based on this approach, the entire filter bank was achieved by the iterative use of signal down sampling. In each 1/3-octave frequency band, the root-mean-square (RMS) energy was estimated and achieved energy was transformed into decibels. A sum of energy contained in the entire 1/3-octave spectra was used as a reference value for the transformation into decibels, as described by Eq. (1). (1) E i = 10log 10 E filtered i ∑ k = 1 18 E filtered k , where Efiltered is energy contained in the single band of 1/3-octave and E(i) is the decibel value of energy contained in the ith band.Figure 1: Principle of acoustic analysis based on the 1/3-octave spectra assessment presented in Couvreour (1998).
Considering the effect of spectral flattening, nasality in sustained phonation of the vowel /i/ was evaluated using the EFn parameter, which represented energy in a 1/3-octave band centered around 1 kHz (passband from 890.9 Hz to 1122.5 Hz). This parameter reflected the addition of nasal resonance and additive nasal pole to the transfer function at 1 kHz. The overall level of hypernasality was estimated by the mean value of EFn parameter (EFn mean) across all windows in the entire utterance. The variability of nasality (EFn SD) in speech was evaluated as the standard deviation of each parameter across the entire utterance. Finally, the evolution of hypernasality in the course of the utterance (EFn trend) was described using a linear regression tangent for each parameter.Statistics
As the vowel /i/ was recorded twice for all speakers, average values of estimated acoustic parameters EFn mean, EFn SD and EFn trend for each participant were used for all consecutive analyses.
The Kolmogorov–Smirnov test for independent samples was used to evaluate normality. Analysis of variance (ANOVA) with post-hoc Bonferroni adjustment was used for the estimation of group differences between PD, HD and HC groups across acoustic variables.
Relationships between variables were evaluated using Pearson’s correlation and Spearman’s correlation. Pearson’s correlation was applied to normally distributed data (acoustic speech metrics and disease severity scores), whereas Spearman’s correlation was used for non-normally distributed data (perceptual assessment of nasality and dysarthria severity). The Bonferroni adjustment for multiple comparisons was performed according to the four measures investigated (EFn mean, EFn SD, EFn trend, and perceptual assessment) and the level of significance was set at p < 0.0125.
Due to the lack of information necessary for the classification of hypernasality, the assessment of the percentage of affected participants from acoustic data was based on the Wald task, which enables setting the classification specificity and sensitivity and therefore allows a more conservative threshold. The Wald task is a non-Bayesian statistical decision-making method which assumes that the dataset consists of two statistical distributions representing positive and negative cases and enables predefining false positive and false negative classifications by extending two basic classes (i.e., healthy and hypernasal), by an indecisive class (Schlesinger & Hlavac, 2002). Use of the indecisive class enables set boundaries where the possibility of a false positive or false negative result reaches a predefined value. Therefore, the indecisive class is used in cases where measured data do not provide sufficient information for clear-cut classification. In such cases, the user can decide whether the indecisive results would be discarded, incorporated with positive results providing the classifier with greater sensitivity and smaller selectivity or labeled as negative producing a less sensitive and more selective classifier. As a result, the method provides optimal cut-off values indicating if the subject already reached hypernasal speech performance or manifest normal nasality of wider norm of healthy speakers. In other words, the approach based on the Wald task avoids classifier overtraining and ensures certain confidence that cut-off values will be associated with hypernasal behavior. Comprehensive details on the Wald task have been published previously (Rusz et al., 2011).Results Perceptual analysis
According to UPDRS III speech item 18, 10 PD patients (27%) demonstrated no speech impairment (score of 0), 32 PD patients (62%) mildly affected speech (score of 1) and 4 PD patients (11%) moderately affected speech (score of 2). According to the UHDRS speech item, eight HD patients (22%) showed normal speech (score of 0) and 29 HD patients (78%) dysarthria without the necessity of repeating speech to be intelligible (score of 1). In summary, the speech of all PD and HD patients was still fully understandable as indicated by UPDRS speech item 18 (ranging between 0 and 2) as well as the UHDRS speech item (ranging between 0 and 1).
The distribution of participants across four perceptual rating grades (no, mild, moderate, severe) are presented in Fig. 2. According to perceptual tests, 65% of PD and 89% of HD patients showed mild or moderate hypernasal speech performance, whereas mild hypernasality was observed in 22% of healthy speakers. The estimated inter-rater reliability was 0.85 (p < 0.001) across all raters and the intra-rater reliability ranged between 0.77 (p < 0.05) and 0.85 (p < 0.001) between individual raters.Figure 2: Percentage occurrence of hypernasality across participants according to the four grades perceptual score (0, no; 1, mild; 2, moderate; 3, severe) based on GOS.SP.ASS.’98 (Sell, Harding & Grunwell, 1999). Acoustical analysis
Figure 3 illustrates the average energy distributions in PD, HD and HC groups across 18 frequency bands. As can be seen, the HD group demonstrates spectral flattening in the area between the F1 and F2 formant frequencies.Figure 3: Measured average values of 1/3-octave spectra for 75–4,000 Hz bands with error bars indicating standard deviation for PD, HD and HC groups.
Analysis of test–retest reliability of the proposed parameter EFn showed strong correlation for mean (r = 0.87, p < 0.001) and SD (r = 0.79, p < 0.001) parameters, whereas trend analyses showed only moderate correlation (r = 0.47, p < 0.001). Table 1 lists the results of acoustic analyses. Statistically significant differences between all groups were observed for EFn mean and EFn SD (p < 0.001), particularly due to differences between HD and HC groups (p < 0.001).Table 1:
Results of hypernasality measures including mean and SD values for EFn mean, EFn SD and EFn trend parameters across PD, HD and HC groups as well as results of ANOVA including F, p, and η2 values.Based upon post-hoc Bonferroni comparisons, an asterisk (∗) indicates statistically significant differences between HD and HC groups at the p < 0.001 level of significance. Measurement PD HD HC ANOVA Mean SD Mean SD Mean SD F(2, 108) p η2 EFn mean (dB) −38.93 4.37 −34.85 4.59 −39.10 3.06 11.82 p < 0.001* 0.179 EFn SD (dB) 2.17 0.64 4.29 2.17 2.03 0.44 59.08 p < 0.001* 0.382 EFn trend (dB/s) −4.784 18.58 −2.22 82.32 −3.68 17.76 0.21 p = 0.81 0.000
Figures 4A–4C shows the percentage of affected participants according to Wald analysis. Using a cutoff value of −33 dB for EFn mean, we found increased nasality in 27% of PD, 54% of HD and 19% of HC speakers. In addition, based upon a cutoff value of 3 dB for EFn SD, we observed abnormal nasality variability in 27 % of PD, 78% of HD and 11 % of HC participants.Figure 4: Percentage of participants marked as hypernasal using (A) EFn mean, (B) EFn SD and (C) overall perceptual rating. Relationship between perceptual and acoustic analysis
Figure 4 shows comparisons related to the percentage of participants rated as hypernasal by acoustic methods and the overall perceptual score obtained across all raters for PD, HD, and HC groups. We observed significant correlation between overall perceptual rating and the acoustic EFn SD parameter (r = 0.51, p < 0.001) but not EFn mean parameter (r = 0.09, p = 0.35) or EFn trend parameter (r = 0.08, p = 0.38).Relationship between hypernasality and clinical manifestations
Table 2 lists results of correlations between hypernasality measurements and clinical manifestations for PD and HD groups. In the PD group, we did not detect any relationship between acoustic assessment of hypernasality and clinical metrics. In the HD group, we observed only significant relationships between the UHDRS chorea subscore and EFn SD (r = 0.42, p = 0.01) and between UHDRS speech item and EFn SD (r = 0.46, p = 0.01). We did not detect correlation between perceptual assessment and clinical manifestations in either PD or HD groups.Table 2:
Results of correlations between acoustical and perceptual measures of hypernasality and clinical manifestations of PD and HD groups.r(p) EFn mean EFn SD EFn trend Perceptual assessment PD UPDRS III −0.10 (0.56) 0.14 (0.41) 0.04 (0.83) −0.06 (0.74) UPDRS III speech item 18 −0.06 (0.75) 0.26 (0.12) 0.23 (0.18) 0.27 (0.11) UPDRS III bradykinesia subscore −0.11 (0.50) 0.15 (0.36) 0.08 (0.62) −0.05 (0.75) Disease duration 0.20 (0.24) −0.32 (0.06) −0.16 (0.34) −0.06 (0.72) HD UHDRS −0.01 (0.96) 0.39 (0.02) 0.23 (0.19) 0.37 (0.03) UHDRS speech item −0.09 (0.59) 0.46 (0.01) −0.07 (0.70) 0.16 (0.35) UHDRS chorea subscore 0.27 (0.12) 0.42 (0.01) 0.05 (0.76) 0.08 (0.63) Disease duration 0.09 (0.60) 0.28 (0.10) 0.00 (0.99) −0.05 (0.80) Discussion
In the present study, we analyzed hypernasality in PD, HD and HC utterances using objective acoustic analyses as well as perceptual assessment, which represents current gold standard for hypernasality evaluation. Based upon the 1/3-octave spectra analysis presented by Kataoka et al. (1996) and the acoustic model of the vocal tract published by Fant (1960), we designed the parameter EFn to evaluate the presence and character of hypernasality in prolonged vowels. Using acoustic analysis, we revealed an occurrence of hypernasality in 27% of PD, 54% of HD and 19% of HC speakers. In addition, our results showed a high occurrence of intermittent hypernasality in 78% of HD patients. Perceptual analysis showed the occurrence of mild to moderate hypernasality in 65% of PD, 89% HD and 22% HC speakers. Significant correlation between the acoustic parameter representing nasality fluctuation and perceptual assessment was observed. Furthermore, we revealed significant correlation between acoustic metric representing nasality fluctuation and chorea in HD patients.Nasality in PD
Although using acoustic analysis we detected hypernasality in 27% of PD speakers, the non-significant difference between PD and HC groups suggests that hypernasality is a non-prominent speech manifestation. Previous studies focused on hypernasality in PD have provided rather inconsistent conclusions. Based on perceptual evaluation, Ludlow & Basich (1983) included hypernasality among the 10 most salient features connected with dysarthria, whereas Logemann et al. (1978) observed hypernasality in only 10% of participants based on a large sample of PD patients. Considering instrumental analyses, only Mueller (1971) failed to detect hypernasality in PD speakers, contrary to the majority of studies reporting an increased occurrence of hypernasality in PD participants (Hoodin & Gilbert, 1989; Netsell, Daniel & Celesia, 1975; Theodoros, Murdoch & Thompson, 1995). While the differences in perceptual assessments could be explained by the fact that listeners from various cultures may have a different level of tolerance for perceived hypernasality, inconsistencies in the instrumental assessment are likely due to the differing sensitivity of particular methods. Moreover, both perceptual and instrumental assessment could be biased by differences in the sample data, as the majority of previous studies have reported hypernasality in a minority of PD speakers. One further explanation for these discrepancies may be that the severity of hypernasality parallels overall disease progression to some extent (Hoodin & Gilbert, 1989). However, we did not observe any relation between hypernasality metrics and disease duration, speech severity, or motor severity scales in PD.Nasality in HD
The presence of hypernasality was observed both perceptually and acoustically in the majority of our HD speakers, which was mainly associated with the occurrence of abnormal nasality variability. Indeed, we observed correlation between acoustic nasality variability and the chorea UHDRS subscore, demonstrating the significant impact of chorea on velopharyngeal mechanism. Although our findings seem to be in accordance with Duffy (2013) that perceptually indicated intermittent hypernasality as a salient feature of patients manifesting chorea, there appear to be no other empirical data to support the results of the present study. Additionally, we also revealed relationship between acoustic nasality variability and overall dysarthria severity, indicating that the extent of abnormal nasality partially parallels increasing overall speech dysfunction in HD.Perceptual assessment of hypernasality
Previous studies have reported perceptual assessment of hypernasality in dysarthria as rather unreliable as hypernasality is less apparent to the listener due to the presence of more dominant dysarthria manifestations (Brancewicz & Reich, 1989). Nevertheless, although perceptual assessment of nasality in dysarthrias is challenging, it is still considered the gold standard, even in studies investigating acoustic techniques. Our results indicate more HD and PD participants systematically rated as hypernasal by perceptual assessment than by an instrumental approach, likely due to difficulty in achieving accurate perception of hypernasality when other abnormal dysarthria characteristics are present. Furthermore, the difference between speech tasks used during perceptual and instrumental evaluation could be a source of discrepancy between acoustic and perceptual assessments.
There is a little evidence for correlation between perceptual and instrumental measurements of hypernasality in dysarthrias (Poole et al., 2015; Theodoros, Murdoch & Thompson, 1995). In our HD sample, acoustic analyses identified only 50% of all HD speakers as hypernasal in comparison to the perceptual rating of nearly 90%. Yet, the abnormally intermittent character of nasality was also acoustically observed in nearly 80% of all HD participants. As we observed significant correlation between acoustic parameters measuring intermittent hypernasality and perceptual ranking, we may hypothesize that fluctuation in the level of nasality makes resonatory disruptions more obvious to perceptual raters. Interestingly, these correlations were evident even if perceptual and acoustic assessment were performed using different speech material.
In agreement with our findings, previous studies have perceptually rated the majority of PD participants as mildly hypernasal (Hoodin & Gilbert, 1989; Theodoros, Murdoch & Thompson, 1995). However, our raters tended to evaluate PD utterances with higher nasality scores in ambiguous cases. Indeed, some mild hypernasality is not rare even in healthy subjects and was observed in up to 22% of our control speakers, which is in accordance with previous research (Poole et al., 2015). Given this evidence, we may suppose that the perceptual decision between normal and mildly hypernasal speech can be misleading, particularly in dysarthrias with other perceptually dominant speech deviations.Acoustic assessment of hypernasality
In the present study, we applied an acoustic method designed for the objective evaluation of velopharyngeal insufficiency, to determine the presence and nature of velopharyngeal incompetence in PD and HD. This methodology has been previously found to be superior to other acoustic measures of hypernasality (Vogel et al., 2009), and was later successfully applied to patients with Friedreich ataxia resulting in velopharyngeal incompetence (Poole et al., 2015). Based upon an acoustic model of the vowel /i/ published by Stevens (2000) and recommendations presented by Kent et al. (1999), we designed the EFn parameter to describe the presence of nasal resonance in speech due to properties of the nasal cavity present in the 1 kHz 1/3-octave band (Kataoka et al., 1996; Stevens, 2000). This assumption is valid for all vowels; nevertheless, the wide plateau between F1 and F2 frequencies in the vowel /i/ makes the presence of nasal resonance more pronounced (Kataoka et al., 1996; Stevens, 2000). Compared to controls, the parameter EFn mean showed significantly increased energy in HD patients, suggesting an abnormal presence of hypernasality in HD patients. Furthermore, using the parameter EFn SD, we revealed significant differences in fluctuations of nasality between HD and control speakers, suggesting intermittent hypernasality in HD patients. The parameter EFn trend was found to be unreliable, as it demonstrated no significant differences between groups and low test–retest reliability.Limitations of the current study
We did not perform aerodynamic measurements, which would provide direct information about nasal airflow. Nevertheless, a previous study by Vogel et al. (2009) provided exhaustive evaluation of the 1/3-octave method and other studies have successfully applied this method to hypernasality assessment (Kataoka et al., 1996; Lee, Ciocca & Whitehill, 2003; Poole et al., 2015; Yoshida et al., 2000). The advantage of the current approach is that it provides an easy-to-administer acoustic assessment, which would be possible to integrate into a larger battery of acoustic tests.
It is noteworthy that the choice of the vowel /i/ may serve to maximize the impact of nasality or at least the likelihood of an acoustic model finding nasality. Thus, previous research on nasality in children used not only the optimal /i/ but a greater variety of speech material (Vogel et al., 2009). Therefore, the higher incidence of hypernasality, particularly in HD patients, due to a maximized impact of nasality cannot be excluded. Conversely, the results of perceptual tests suggest an even greater level of nasality across our participants than we were able to capture using acoustic assessment, indicating that level of nasality assessed using the 1/3-octave spectra method was not necessarily overestimated. Furthermore, the effect of maximizing nasality may be beneficial due to the fact that it emphasizes the presence of hypernasality among other dysarthria manifestations.
One limitation is that we used different speech tasks for the perceptual and acoustic evaluation of hypernasality, as accurate perceptual evaluation of hypernasality from sustained vowel phonation is not feasible. Indeed, the different speech tasks used likely make correlation analyses between perceptual and acoustic variables problematic. In future studies, it may therefore be beneficial to include rating for consistency, as with the Consensus Auditory Perceptual Evaluation of Voice (Kempster et al., 2009).
We did not test the consistency and reliability of UPDRS and UHDRS metrics. Nevertheless, relationships between nasality and motor abnormalities were found only for the UHDRS chorea subscore, which showed high inter-rater reliability with an ICC of 0.82 (Huntington-Study-Group, 1996).
As the presence of chorea in HD is unlikely to be limited only to specific parts of the vocal tract such as the soft palate, we cannot exclude that EFn SD is also, to a certain extent, influenced by other manifestations of chorea, particularly laryngeal chorea (Rusz et al., 2013).
As HD generally has an earlier onset than PD, the PD and HD participant groups could not be age-matched. Therefore, we matched the age of the control group to the age of generally older PD group, as nasality is expected to remain stable throughout life or may slightly deteriorate as a consequence of aging (Hoit et al., 1994; Ramig & Ringel, 1983). This approach ensures that the results of the PD group were not favored in comparison with the HC group. Moreover, we did not match our groups according to gender. Nevertheless, previous studies did not find differences in nasality between male and female speakers (Joos et al., 2006; Litzaw & Dalston, 1992).Conclusion
Perceptual and acoustic data presented in the current study provide evidence of significantly increased and intermittent hypernasality in HD patients, presumably due to choreatic movements of the velopharyngeal mechanism. Although the presence of hypernasality was also observed in several PD speakers, abnormal nasality is not a prominent feature of hypokinetic dysarthria. However, further research is warranted. The relationships between proposed acoustic metrics and aerodynamic measurements for evaluation of hypernasality in dysarthrias should be explored. Future longitudinal studies are needed to confirm and further elaborate our findings and to show reliability of hypernasality measures as a possible marker of disease progression in basal ganglia disorders. Last but not least, as hypernasality is a prominent sign in several dysarthria subtypes (Duffy, 2013), sensitivity of methods proposed in the present study should be verified across various neurological disorders and measure of hypernasality may be useful in characterization of progressive neurological disorders as well as may have potential to provide important clues about the pathophysiology of underlying disease.Supplemental Information Raw data related to assessment of hypernasality
Dataset containing acoustic and perceptual hypernasality scores and clinical informations related to investigated subjects.Matlab code for nasality analysis
Dutch adolescents often start drinking alcohol at an early age. The life-time prevalence for drinking alcohol is 56% for twelve year olds and 93% for sixteen year olds. Also, 16% of twelve year olds and 78% of sixteen year olds drink alcohol regularly. In comparison with other young people in Europe, Dutch adolescents drink more frequently and are more likely to be binge drinkers (episodic excessive alcohol consumption, defined as drinking 5 glasses or more on a single occasion in the last four weeks) .
Despite a sharp decline in the excessive consumption of alcohol (6 or more glasses at least once a week for the last 6 months) among adolescents in the Netherlands, the alcohol consumption is still high . Data from the Regional Health Services (RHS) in the province of North Brabant  also show this. Although the number of young people who regularly consume alcohol (at least once in the past 4 weeks) declined from 54% in 2003 to 44% in 2007, 28% of the 12 to 17 year olds in the area of the RHS “Hart voor Brabant” can be identified as binge drinkers. Moreover, 25% of the under 16s are regular drinkers, and 13% are even binge drinkers.
Alcohol consumption by adolescents under 16 causes severe health risks. Firstly, young people's brains are particularly vulnerable because the brain is still developing during their teenage years. Alcohol can damage parts of the brain, affecting behavior and the ability to learn and remember . Secondly, there is a link between alcohol consumption and violent and aggressive behavior [5–7] and violence-related injuries. Thirdly, young people run a greater risk of alcohol poisoning when they drink a large amount of alcohol in a short period of time . Finally, the earlier the onset of drinking, the greater is the chance of excessive consumption and addiction in later life [9–11].
The policy of the Dutch Ministry of Health is aimed at preventing alcohol consumption among adolescents younger than 16, and at reducing harmful and excessive drinking among 16–24 years old young adults . Local Authorities are responsible for the implementation of national alcohol policy at a local level. RHSs and regional organizations for the care and treatment of addicts carry out prevention activities at a regional and local level, often commissioned by Local Authorities.
Current policies and interventions are mainly directed at settings such as schools and sports clubs. However, it is unlikely that this approach will have sufficient impact on adolescents, because the groups in these settings are heterogeneous. Adolescents differ in their drinking habits and have different attitudes towards alcohol. This means that one intervention reaches only a part of all adolescents, and doesn’t reach other adolescents, with a different drinking habit or a different attitude.
Market research has revealed the importance and effectiveness of tailoring messages and incentives to meet the needs of different population segments. Not every individual is a potential consumer of a given product, idea, or service; so tailoring messages to specific groups will be more effective than broadcasting the same message to everyone [13, 14].
Audience segmentation is a method for dividing a large and heterogeneous population into separate, relatively homogeneous segments on the basis of shared characteristics known or presumed to be associated with a given outcome of interest .
Audience segmentation is fairly common in the field of public health. However, such segmentation is usually based on socioeconomic and demographic variables, such as age, ethnicity, gender, education and income. Unfortunately, demographic segmentation alone may be of limited use for constructing meaningful messages . While psychographic and lifestyle analyses have long been standard practice in business marketing, their use in public health communication efforts is still much less common . Since health messages can be fine-tuned to the differences in lifestyle such as attitudes and values, segments based on aspects of lifestyle are expected to be more useful for health communication strategies [14, 16]. We assume that attitudes, values, and motives in relation to alcohol consumption among adolescents will vary, and may therefore offer a better starting point for segmentation than socio-demographic characteristics alone. For example, previous research has shown that motives for drinking give rise to a substantial part of the variance in alcohol consumption [17, 18]. Moreover, personality traits, such as sensation seeking, are associated with quantity and frequency of alcohol use .
Despite the promising characteristics of audience segmentation based on lifestyle aspects, it has never been used in the Netherlands in relation to the prevention of alcohol consumption. That is why the RHS “Hart voor Brabant”, in cooperation with market research office Motivaction®, conducted a study to find out whether it is possible to identify different segments on the basis of the motives, attitudes, and values of adolescents towards alcohol. The first results of this study were already published in a Dutch article .
Niels Röling and Jules N. Pretty
Niels Röling is Extra-ordinary Professor of agricultural knowledge systems, Department of Communication and Innovation Studies, Wageningen Agricultural University, Wageningen, Netherlands. Jules N. Pretty is the Director of Sustainable Agriculture Programmes, International Institute for Environment and Development, London.
Emerging challenges for sustainable agricultureSustainability and levels of actionResource-conserving technology development and transferIncorporating farmer experimentationFrom teaching to learning and a whole new professionalismFrom directive to participatory extensionChallenges for supportive policy processesReferences
During the past fifty years, agricultural development policies have been remarkably successful at emphasizing external inputs as the means to increase food production. This has led to growth in global consumption of pesticides, inorganic fertilizer, animal feed-stuffs, and tractors and other machinery.
These external inputs have, however, substituted for natural processes and resources, rendering them less powerful. Pesticides have replaced biological, cultural, and mechanical methods for controlling pests, weeds, and diseases; inorganic fertilizers have substituted for livestock manures, composts, and nitrogen-fixing crops; information for management decisions comes from input suppliers, researchers, and extensionists rather than from local sources; and fossil fuels have substituted for locally generated energy sources. The basic challenge for sustainable agriculture is to make better use of these internal resources. This can be done by minimizing the external inputs used, by regenerating internal resources more effectively, or by combinations of both.
Evidence is now emerging that regenerative and resource-conserving technologies and practices can bring both environmental and economic benefits for farmers, communities, and nations. The best evidence comes from countries of Africa, Asia, and Latin America, where the concern is to increase food production in the areas where fanning has been largely untouched by the modem packages of externally supplied technologies. In these complex and remote lands, some farmers and communities adopting regenerative technologies have substantially improved agricultural yields, often using only few or no external inputs (Bunch, 1991; GTZ, 1992; UNDP, 1992; Lobo & Kochendörfer-Lucius, 1992; Krishna, 1993; Shah, 1994; SWCB, 1994; Pretty, 1995).
But these are not the only sites for successful sustainable agriculture. In the high-input and generally irrigated lands, farmers adopting regenerative technologies have maintained yields whilst substantially reducing their use of inputs (Kamp, Gregory, & Chowhan, 1993; UNDP, 1992; Kenmore, 1991; van der Werf & de Jager, 1992; Bagadion & Korten, 1991). And in the very high-input lands of the industrialized countries, farmers have been able to maintain profitability even though input use has been cut dramatically, such as in Europe (Vereijken, 1992; Vereijken, Wijnands, Stol, & Visser, 1994; Van Weeperen, Röling, Van Bon, & Mur, 1995; Pretty & Howes, 1993; Jordan, Hutcheon, & Glen, 1993; El Titi & Landes, 1990) and in the United States (Liebhart et al., 1989; NRC, 1989; Hanson, Johnson, Peters, & Janke, 1990; Dobbs, Becker, & Taylor, 1991; Faeth, 1993).
All of these successes have three elements in common. They have made use of resource-conserving technologies such as integrated pest management, soil and water conservation, nutrient recycling, multiple cropping, water harvesting, and waste recycling. In all, there has been action by groups and communities at the local level, with farmers becoming experts at managing farms as ecosystems and at collectively managing the watersheds or other resource units of which their farms form a part. And there have also been supportive and enabling external government and nongovernment institutions, which have reoriented their activities to focus on local needs and capabilities.
Most successes, though, are still localized. They are simply islands of success. This is because an overarching element, a favourable policy environment, is missing. Most policies still actively encourage fanning that is dependent on external inputs and technologies. It is these policy frameworks that are one of the principal barriers to a more sustainable agriculture (Pretty, 1994a). Figure 1 illustrates this chapter's area of discourse and its focus on the interfaces between natural resources, local stakeholders, supportive institutions, and the policy context.
A necessary condition for sustainable agriculture is that large numbers of farming households must be motivated to use coordinated resource management. This could be for pest and predator management, nutrient management, controlling the contamination of aquifers and surface water courses, coordinated livestock management, conserving soil and water resources, and seed stock management. The problem is that, in most places, platforms for collective decision making have not been established to manage such resources (Röling, 1994a, 1994b). The success of sustainable agriculture therefore depends not just on the motivations, skills, and knowledge of individual farmers, but on action taken by groups or communities as a whole. This makes the task more challenging. Simple extension of the message that sustainable agriculture can match conventional agriculture for profits, as well as produce extra benefits for society as a whole, will not suffice.
Sustainability is commonly seen as a property of an ecosystem. But Sustainability can be seen from other perspectives, which are more relevant for extension. Environmental issues emerge from the human use of natural resources. Sustainability can therefore be defined in terms of human reasons, activities, and agreements. The definition of Sustainability then becomes part of the problem because people need to agree on how they define Sustainability and what priority they will give it (Pretty, 1994b).
In this approach, Sustainability is not a scientific, "hard" property which can be measured according to some objective scale, or a set of practices to be fixed in time and space. Rather, Sustainability is a quality that emerges when people individually or collectively apply their intelligence to maintain the long-term productivity of the natural resources on which they depend (Sriskandarajah, Bawden, & Packham, 1989). In other words, Sustainability emerges out of shared human experiences, objectives, knowledge, decisions, technology, and organization. Agriculture becomes sustainable only when people have reason to make it so. They can learn and negotiate their way towards Sustainability. In any discussions of Sustainability, it is important to clarify what is being sustained, for how long, for whose benefit and at whose cost, over what area, and measured by what criteria. Answering these questions is difficult, because it means assessing and trading off values and beliefs. Campbell (1994) has put it this way: "[Attempts to define Sustainability miss the point that, like beauty, sustain ability is in the eye of the beholder.... It is inevitable that assessments of relative Sustainability are socially constructed, which is why there are so many definitions."
It is therefore crucial to focus on more than one system level (Fresco, Stroosnijder, Bouma, & van Keulen, 1994). At the farm level, there is the farm household. At the above-farm level, there are the collective stakeholders, who might or might not be organized for sustainable use of the whole resource unit. In an irrigation scheme, it is common for an irrigators' association collectively to manage water use at the scheme level. But when it comes to watersheds or other vulnerable resource units, it is usually impossible to identify an appropriate "platform" for decision making (Röling, 1994a, 1994b).
A key example is the Indonesian programme for integrated pest management (IPM) in irrigated rice (FAO, 1994; Van de Fliert, 1993; Röling & Van de Fliert, 1994; Kenmore, 1991). At the farm level, this programme involves farmer field schools teaching individual farmers to manage their rice plots as ecosystems, carefully maintaining the balance between pests and their natural predators and only reverting to pesticides when observation shows that the situation is running out of hand. But IPM also needs collective management of resources comprising several farms. Thus nematodes can effectively be controlled by interrupting the cultivation of wet rice by a dryland crop such as soybeans. This requires decision making at the irrigation block level. The population dynamics of rats, the most important pest in irrigated rice, cannot be controlled at the farm level. Integrated rat management requires collective action at the village level (Van de Fliert, van Elsen, & Nangsir Soenanto, 1993).
Although many resource-conserving technologies and practices have been widely proven on research stations to be both productive and sustainable, the total number of farmers using them is still small. This is because these technologies involve the substitution of management skills, knowledge, and labour for external inputs. The modern approach to agricultural research and extension, however, has been to emphasize comprehensive packages of technologies. Few farmers are able to adopt the whole modem packages of production or conservation technologies without considerable adjustments. Part of the problem is that most agricultural research still occurs on the research station, where scientists experience conditions quite different from those experienced by farmers.
This is true of many sustainability-enhancing innovations. Even though resource-conserving technologies are productive and sustainable, if they are imposed on farmers, then they will not be adopted widely. Alley cropping, an agroforestry system comprising rows of nitrogen-fixing trees or bushes separated by rows of cereals, has long been the focus of research (Kang, Wilson, & Lawson, 1984; Attah-Krah & Francis, 1987; Young, 1989; Lal, 1989). Many productive and sustainable systems, needing few or no external inputs, have been developed. They stop erosion, produce food and wood, and can be cropped over long periods. But the problem is that very few, if any, farmers have adopted these alley cropping systems as designed. Despite millions of dollars of research expenditure over many years, systems that have been produced are suitable only for research stations.
Where these systems have had some success, however, farmers have taken one or two components of alley cropping and adapted them to their own farms. In Kenya, for example, farmers planted rows of leguminous trees next to field boundaries, or single rows through their fields; and in Rwanda, alleys planted by extension workers soon became dispersed through fields (Kerkhof, 1990). But the prevailing view tends to be that farmers should adapt to the technology. Of the Agroforestry Outreach Project in Haiti, it was said:
Farmer management of hedgerows does not conform to the extension program.... Some farmers prune the hedgerows too early, others too late. Some hedges are not yet pruned by two years of age, when they have already reached heights of 4-5 metres. Other hedges are pruned too early, mainly because animals are let in or the tops are cut and carried to animals.... Finally, it is very common for farmers to allow some of the trees in the hedgerow to grow to pole size. These trees are not pruned but are harvested when needed for house construction or other activities requiring poles. (Bannister & Nair, 1990)
Farmers were clearly making their own adaptations according to their own needs.
Just occasionally, however, an environmentally beneficial technology is developed that appears to require no knowledge of farmers' conditions. The IPM programme to control cassava mealybug (CMB) (Phenacoccus manihoti) in west and central Africa is one example. CMB was first recorded in Africa in 1973, and an effective natural enemy, the wasp Epidinocarsis lopezi, was found in 1981. Since releases began, it has become established in twenty-five countries, providing good control of CMB. It is to some extent a "perfect technology" for scientists, because it is released from the air without the knowledge of farmers. It is, however, not necessarily a perfect technology for farmers. The contrast with another IPM programme in Togo is significant when it comes to issues of sustainability (Box 1).
The problem with agricultural science and extension is that it has poorly understood the nature of "indigenous" and rural people's knowledge. For many, what rural people know is assumed to be "primitive," "unscientific," or overtaken by development, and so formal research and extension must "transform" what they know so as to "develop" them. An alternative view is that local knowledge is a valuable and underused resource, which can be studied, collected, and incorporated into development activities. Neither of these views, though, is entirely satisfactory because of the static view of knowledge implied (Chambers, Pacey, & Thrupp, 1989; Röling & Engel, 1989; Warren, 1991; Long & Long, 1992; Scoones & Thompson, 1994). It is more important to recognize that local people are always involved in active learning, in (re)inventing technologies, in adapting their farming systems and livelihood strategies. Understanding and supporting these processes of agricultural innovation and experimentation have become an important focus in facilitating more sustainable agriculture with its strong locality-specific nature.
The problem with modem agricultural science is that technologies are finalized before farmers get to see them. If new technologies are appropriate and fit a particular farmer's conditions or needs, then they stand a good chance of being adopted. But if they do not fit and if farmers are unable to make changes, then they have only the one choice. They have to adapt to the technology, or reject it entirely.
Box 1. Comparison of Farmers' Involvement in Two IPM Programmes.
A: Cassava mealybug (CMB) control with Epidinocarsis lopezi
The programme has involved close collaboration between IITA and NARSs, involving training of local technicians to participate in releases. Now mass rearing of the wasp E. lopezi is done in Benin; from there they are transported by air for air release. According to IITA, an important component of success has been that farmers and extension agents have not had to be involved. Farmers do not, therefore, know anything about the releases. One survey of farmers in Ghana and Cote d'Ivoire found that they recognized CMB and how it was a devastating pest. All those where E. lopezi had been introduced at least six months before had observed a significant decline in CMB. But because none of them knew about the programme, they attributed the decline to recent heavy rains and other climatic factors.
B: Mango mealybug control in Togo
The CMB programme is in contrast to the successful introduction of the parasitoid Gyranusoides tebyii to Togo in 1987 to control the mango mealybug (Rastrococcus invadens). The parasitoid was found in India, and following testing, rearing, and release, it rapidly spread over the whole of Togo. By 1989, no mango trees could be found on which mango mealybug was present without being parasitized. But success would be threatened without public interest, as any use of chemical control methods would kill the parasites. A great deal of publicity was given through radio, TV, and advisory leaflets. Considerable economic losses are now being prevented by the biological control system.
Source: Kiss and Meerman (1991).
The alternative is to seek and encourage the involvement of farmers in adapting technologies to their conditions. This constitutes a radical reversal of the normal modes of research and technology generation, because it requires interactive participation between professionals and farmers. Participatory technology development (PTD) is the process in which the knowledge and research capacities of farmers are joined with those of scientific institutions, whilst at the same time strengthening local capacities to experiment and innovate (Jiggins & De Zeeuw, 1992; Reijntjes, Haverkort, & Waters-Bayer, 1992; Haverkort, van der Kamp, & Waters-Bayer, 1991). Farmers are encouraged to generate and evaluate indigenous technologies and to choose and adapt external ones on the basis of their own knowledge and value systems.
But, of course, researchers and farmers participate in different ways, depending on the degree of control each actor has over the research process. The most common form of "participatory" research is researcher designed and implemented, even though it might be conducted on farmers' fields. Many on-farm trials and demonstration plots represent nothing better than passive participation (Pretty, 1994b). Less commonly, farmers may implement trials designed by researchers. But greater roles for farmers are even rarer. Fujisaka (1991) describes researcher-designed experiments on new cropping patterns in the Philippines. Even though farmers "participated" in implementing the trials, there was widespread uncertainty about what researchers were actually trying to achieve. Farmers misunderstood experiments and rejected the new technologies. The reason, as Fujisaka explains, was that "cooperation between farmers and researchers implies two groups continually listening carefully to one another. Claveria farmers are avid listeners to... researchers. The challenge is for all on-farm researchers to complete the circle."
Although this means that technology development must involve farmers, it does not mean that scientific research has no place. Research will have to contribute on many fronts, such as in the development of resistant cultivars, knowledge about the life cycles of pests, biological control methods, suitable crops for erosion control, and processes in nitrogen fixation. Such research also gives insight into complex processes such as the movement of nutrients in the soil and their accessibility for plants. But all these contributions must be seen as providing choices for farmers as they make farm-specific decisions and move the whole farm towards greater sustainability.
The central principle of sustainable agriculture is that it must enshrine new ways of learning about the world. But learning should not be confused with teaching.
Teaching implies the transfer of knowledge from someone who knows to someone who does not know. Teaching is the normal mode of educational curricula and is also central to many organizational structures (Ison, 1990; Argyris, Putnam, & Smith, 1985; Russell & Ison, 1991; Bawden, 1992, 1994; Pretty & Chambers, 1993). Universities and other professional institutions reinforce the teaching paradigm by giving the impression that they are custodians of knowledge which can be dispensed or given (usually by lecture) to a recipient (a student). Where these institutions do not include a focus on self-development and on enhancing the ability to learn, they do not allow students to grasp an essential skill in the sustainable management of a complex agroecosystem. In that case, "teaching threatens sustainable agriculture" (Ison, 1990).
The problem for farmers is that they cannot rely on routine, calendar-based activities if they engage in sustainable farming. Their interventions must be based on observation and anticipation. They require instruments and indicators which make more visible the ecological relationships on and among farms. Technology for sustainable farming must emphasize measurement and observation equipment or services that help individual farmers assess their situations, such as soil analysis, manure analysis, and pest identification (Röling, 1993). It also has to focus on higher system levels. Predators and parasitoids to control pests often require a larger biotope than that of a small farm. Erosion control, water harvesting, biodiversity, access to biomass, recycling waste between town and countryside and between animal and crop production, all require local cooperation and coordination.
What becomes important is the social transition, or new learning path, that farmers and communities must take to support sustainable agriculture. This is much less obvious and often remains unrecognized by extensionists. Learning for sustainable agriculture involves a transformation in the fundamental objectives, strategies, theories, risk perceptions, skills, labour organization, and professionalism of farming. This learning path has four key elements:
1. The information system. Sustainable agriculture must be responsive to changing circumstances, so farmers need to invest in observation, observation equipment, record keeping, and monitoring procedures.
2. Conceptual framework. Sustainable agriculture is knowledge intensive, and so farmers must know about life cycles of pests and disease organisms and their recognition, biological controls, ecological principles, soil life processes, nutrient cycles.
3. Skills. Sustainable farming requires a whole set of new skills, including observation and monitoring, compost making, mechanical weed control, spot application of pesticides, and risk assessment.
4. Higher system-level management. Generally, sustainable management of the farm is not enough, and it is necessary to think at system levels higher than the farm and take part in the collective management of natural resources at those levels.
In educational systems, therefore, the fundamental requirement for sustainable agriculture is for universities to evolve into communities of participatory learners. Such changes are very rare, an exception being Hawkesbury College, which is now part of the University of Western Sydney, Australia (Bawden, 1992, 1994). However, a regional consortium of NGOs in Latin America concerned with agroecology and low-input agriculture recently signed an agreement with eleven colleges of agriculture from Argentina, Bolivia, Chile, Mexico, Peru, and Uruguay to help in the joint reorientation of curriculum and research agendas towards sustainability and poverty concerns (Altieri & Yuryevic, 1992; Yuryevic, 1994). The agreement defines collaboration to develop more systemic and integrated curricula, professional training and internship programmes, collaborative research efforts, and the development of training materials.
Box 2. The Key Principles of Farmer Field Schools.
1. What is relevant and meaningful is decided by the learner and must be discovered by the learner. Learning flourishes in a situation where teaching is seen as a facilitating process that assists people to explore and discover the personal meaning of events for themselves.
2. Learning is a consequence of experience. People become responsible when they have assumed responsibility and experienced success.
3. Cooperative approaches are enabling. As people invest in collaborative group approaches, they develop a better sense of their own worth.
4. Learning is an evolutionary process, and is characterized by free and open communication, confrontation, acceptance, respect, and the right to make mistakes.
5. Each person's experience of reality is unique. As people become more aware of how they learn and solve problems, they can refine and modify their own styles of learning and action.
Sources: Adapted from Kingsley and Musante, 1994; Van de Fliert, 1993; Kenmore, 1991; Stock, 1994.
A move from a teaching to a learning style has profound implications for agricultural development institutions. The focus is less on what we learn, and more on how we learn and with whom (see Box 2 for principles of farmer field schools used in the FAO IPM programme in Southeast Asia). This implies new roles for development professionals, leading to a whole new professionalism with new concepts, values, methods, and behaviour. Typically, normal professionals are single-disciplinary, work largely or only in agencies remote from people, are insensitive to diversity of context, and are concerned with themselves generating and transferring technologies. Their beliefs about people's conditions and priorities often differ from people's own views. The new professionals, by contrast, are either multidisciplinary or work in close connection with other disciplines, are not intimidated by the complexities of close dialogue with rural and urban people, and are continually aware of the context of interaction and development.
Extension has long been grounded in the diffusion model of agricultural development, in which technologies are passed from research scientists via extensionists to farmers (Rogers, 1962, 1983). This approach is exemplified by the training and visit (T&V) system. It was first implemented in Turkey in 1967 and later widely adopted by governments (Benor, 1987; Roberts, 1989). It was designed to be a management system for energizing extension staff, turning desk-bound, poorly motivated field staff into effective extension agents. Extension agents receive regular training to enhance their technical skills, which they then hope will pass to all farmers through regular communication with small numbers of selected contact farmers.
But the contact farmers are usually selected on the basis of literacy, wealth, readiness to change, and "progressiveness," and so this sets them apart from the rest of the community. The secondary transfer of the technical messages, from contact farmers to community, has been much less successful than predicted, and adoption rates are commonly very low among noncontact farmers. Without a doubt, T&V is now widely considered as ineffective (Axinn, 1988; Howell, 1988; Moris, 1990; Antholt, 1992, 1994; Hussain, Byerlee, & Heisey, 1994).
Important lessons have been learned from the problems associated with T&V, and there is clearly a need to address the systemic issues facing extension (Zijp, 1993; Antholt, 1994). Extension will need to build on traditional communication systems and involve farmers themselves in the process of extension. Incentive systems will have to be developed to reward staff for being in the field and working closely with farmers. There must be a "well-defined link between the well-being of field officers and the extension system, based on the clients' view of the value of extension's and field workers' performance" (Antholt, 1992, P.). Participation, if it is to become part of extension, must clearly be interactive and empowering. Any pretence to participation will result in little change. Allowing farmers just to come to meetings or letting a few representatives sit on committees will be insufficient.
There have been some recent innovations in introducing elements of farmer participation and group approaches into extension. Differences in impact between individual and group approaches have been well documented in both Nepal and Kenya. In western Nepal, Sen (1993) compared the rate of adoption of new technologies when extension worked with individuals or with groups. With groups, better communication between farmers and extensionists led to more adoption. When the individual approach was resumed after the experiment, adoption rates fell rapidly in succeeding years.
In Kenya, the Ministry of Agriculture is increasingly adopting a community-oriented approach to soil and water conservation. This is steadily replacing the former individual approach of the T&V system. Where extension staff interact closely with communities in developing joint action plans, and local people freely elect members to a local catchment committee, then the impact on agricultural growth is immediate and sustained. Strong local groups mobilize the interest of the wider community and sustain action well beyond the period of direct contact with external agents. Recent studies comparing the impact of the catchment approach with the individual T&V approach have shown that, for a wide range of indicators, farmers' livelihoods were more improved where the community approach was implemented (SWCB, 1994; Pretty, Thompson, & Kiara, 1994; MALDM, 1988-1994; Eckbom, 1992).
There have been similar successes in IPM, which requires a level of analytical skill and certain basic training in crop monitoring and ecological principles. Where farmers have been trained as experts, such as in Honduras (Bentley, Rodriguez, & Gonzalez, 1993) and in the rice-IPM programmes of Southeast Asia (Kenmore, 1991), then the impacts are substantial. Ordinary farmers are capable of rapidly acquiring and applying the principles and approaches. Fewer programmes are now teaching farmers new technologies and knowledge; rather, they are concerned with developing farmers' own capacity to think for themselves and develop their own solutions. These are producing substantial reductions in insecticide use, whilst maintaining yields and increasing profits (Table 1). But where extension continues to use the conventional top-down approach, then few farmers adopt, let alone learn, the principles. As Matteson (1992) put it: "[F]ew IPM programmes have made a lasting impact on farmer knowledge, attitudes or practice."
There are three major lessons for extension. First, it is important to make new things visible. An important role of extension is to make visible the state of the environment and the extent to which present farming practices are untenable. In addition, extension can demonstrate the feasibility of sustainable practices. Even more important is to give farmers the tools for observation and to train them to monitor the situation on their own farms.
The second lesson is the use of farmers' knowledge. The location-specific nature of sustainable agriculture implies that extension must make use of farmers' knowledge and work together with farmers. Often, indigenous practices which have been ignored under the impact of chemical farming can be fruitfully revived. Indigenous technology development practices and farmer experimentation can be an important "entry point" for introducing sustainable farming practices (Brouwers & Röling, in press).
The third lesson is an emphasis on facilitating learning. Instead of "transferring" technology, extension workers must help farming "walk the learning path" (Box 3). Extension workers should seek to understand the learning process, provide expert advice where required, convene and create learning groups, and help farmers overcome major hurdles in adapting their farms.
Policy making is commonly considered the prerogative of some central authority that formulates a policy, which is then decreed, imposed, and implemented regardless of conflicting knowledge and concerns. But policy is, in practice, often the net result of the actions of different interest groups pulling in complementary and opposing directions. This is particularly true with environmental problems because they are marked by uncertainty, complexity, and high stakes complexity, and high stakes (Funtowicz & Ravetz, 1993). There is therefore a growing tendency to see policy as a negotiated agreement resulting from interaction among citizens, in which central authorities play a facilitating role (Van der Poel & Van Woerkum, 1994). Policy is only effective if it is based on a widely shared consensus. From this perspective, it is easy to see why so many environmental policies which rely on coercion, control, and transfer have failed (Pretty & Shah, 1994; Pimbert & Pretty, 1994).
Box 3. The First Steps on the Learning Path in the Netherlands.
Predator mites were introduced into Dutch fruit orchards to control the red spider mite, which had become resistant to chemical controls. The use of this biological control meant that growers had to learn how to manage their orchards as biotopes for the predator mite. Soon they were carrying magnifying glasses to study the progress of their little helpers. This made them much more observant and accustomed to investing in regular observation. Furthermore, the health of the predator mites precluded use of broad-spectrum pesticides against other pests. As a result, growers also had to learn alternative controls for those pests.
Table 1. Impact of IPM Programmes Involving New Participatory Approaches to Farmer Learning on Pesticide Use and Crop Yields
Country and crop
Average changes in pesticide use (as % of conventional treatments)
Changes in yields (as % of conventional treatments)
Burkina Faso, rice1
USA, nine commodities4
no. of applications up volume applied down
Sri Lanka, rice2
a Even though yields are lower, net returns are much higher.
Sources: (1) Kiss and Meerman, 1991; (2) Kenmore, 1991: Winarto, 1993; van der Fliert, 1993; Matteson et at, 1992; FAO, 1994; (3) Hruska, 1993; (4) NRC, 1989; (5) Kamp et al, 1993; Kenmore, 1991; (6) ICRISAT, 1993
For sustainable agriculture to succeed, policy formulation must arise in a new way. Policy processes must be enabling and participatory, creating the conditions for sustainable development based more on locally available resources and on local skills and knowledge. Effective policy processes will have to bring together a range of actors and institutions for creative interaction and address multiple realities and unpredictability. What is required is the development of approaches that put participation, negotiation, and mediation at the centre of policy formulation so as to create a much wider common ownership in the practices. This is a central challenge for sustainable agriculture. The management of higher level systems, whether common grazing lands, coastal fisheries resources, communal forests, national parks, polders, or watersheds, requires social organization comprising the key stakeholders. All successful moves to more sustainable agriculture have in common coordinated action by groups or communities at the local level (Pretty, 1995). But the problem is that platforms for resource use negotiation generally do not exist, and so need to be created and facilitated (Brinkman, 1994; Röling, 1994a, 1994b).
Different methodologies are emerging to help stake-holders achieve collective resource management capacity. Well known are participatory rapid appraisal (PRA) and related methodologies (see chapter 6). In addition, the soft system methodology (SSM) developed for corporate environments is highly promising for resource use negotiation (Checkland, 1981; Checkland & Scholes, 1990). For stakeholders who have come to appreciate the fact that they share a problem, SSM takes them through a number of steps which allows them to create a "rich picture" on the basis of their multiple perspectives, reach some accommodation with respect to major causes of the problem, and hence decide on collective action. "Rapid appraisal of agricultural knowledge systems" (RAAKS) (Engel, 1995) is a related methodology for facilitating innovation as an emergent property of a knowledge network, comprising such actors as farmers, extension workers, researchers, NGO workers, and policy makers. This system provides stakeholders with different "windows" (such as mission, task differentiation, integration, articulation, coordination, performance) on their own collective practices which allow them to capture the potential synergy of their contributions to innovative performance.
A fundamental requirement if such approaches are to work is that stakeholders in a particular natural resource learn to appreciate that they have a common problem (Box 4). Extension has an important role to play here by making visible the interdependence between stakeholders and the extent to which the resource unit on which they depend has been destroyed by their uncoordinated action and the collective impact of their individual activities. It is within policy contexts thus made conducive for sustainable agriculture that technology development and extension can be especially effective.
Box 4. Resource Mapping by Farmers in Landcare Programme, Australia.
Landcare in Australia provides examples of learning to care for natural resources at higher system levels. Consider resource mapping. Farmers from a subcatchment (usually a subgroup of a Lancare group) are convened by the facilitator of the group to discuss the soils and their susceptibility to erosion. First, a soil typology is established by the farmers through field visits, digging soil pits, and so forth. After a suitable classification (which might deviate considerably from the official scientific one) has been agreed upon, farmers receive an air photo mosaic of the entire subcatchment with their property drawn in. They are also provided with a transparent overlay on which to map the soils and main features of their own properties.
These farmer maps are digitized and fed into GIS software, which allows the property resource maps to be combined into one consolidated subcatchment map. Following meetings to discuss the results, farmers agree on the resource map of the subcatchment and now have a firm grasp of the interaction between their property and the subcatchment. They also realize that vulnerable soils span several properties and that measures to prevent further soil erosion and solination require alignment of fences, roads, vegetation belts, and other features.
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Veeam [2 Certification Exam(s) ]
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