New Developments in Agricultural Policy Modelling and Consequences for Managing the Policy Analysis Systems

Last decade, the importance of multifunctionality and environmental issues in agricultural policies has been growing. This shift in scope of agricultural policy instruments implies an adjustment of the conventional ex-ante policy analysis systems. New requirements on input and output parameters will be needed. The objective of this paper is to show how the input/output management can be improved. Focus is on how the information management by the system can enhance the policy analysis and decision making and facilitate information flow and social support from the stakeholder debate.policy impact analysis, joint production, farmers' behaviour, knowledge flow Organisation, Agricultural and Food Policy, C8, Q18,

Molecular and macromolecular structure changes in polyamide 11 during thermal oxidation

The present article reports a study of thermal oxidation of unstabilized polyamide 11 films at several temperatures (90–165 °C) under atmospheric pressure and under various oxygen pressures (up to 1.6 MPa) at 110 °C. The chemical structure changes are monitored by IR spectroscopy (carbonyl groups) and UV–visible spectrophotometry (yellowing). Molar mass changes are determined by size exclusion chromatography (SEC). By investigating the influence of oxygen pressure it is clearly shown that reactions involving P° radicals other than O2 addition cannot be neglected under atmospheric pressure. Under the conditions of this study limited to relatively low oxidation levels, IR and UV measurements indicate that carbonyl groups and chromophores responsible for yellowing have the same relative yield whatever the temperature and oxygen pressure. SEC measurements highlight the significant predominance of random chain scissions over crosslinking events. Crosslinking only appears after an induction time, presumably because it involves reactions between primary oxidation products. The ratio of carbonyl groups over chain scissions is about 7.5 at low conversion and about 2.5 at high conversion, showing that α amino alkoxy radicals are mainly transformed into imides without chain scission

Contribution à l'étude des rickettsioses du Nord Cameroun. Enquête épidémiologique

Les auteurs ont entrepris chez les bovins du Nord-Cameroun, chez les animaux et l'homme du Centre-Cameroun (Adamaoua) une enquête sérologique sur les rickettsioses et néorickettsioses. Au terme de cette étude ils notent une proportion assez élevée de réponses positives chez les bovins du Nord-Cameroun vis-à-vis des antigènes épidémique, murin, boutonneux. La fièvre Q et les néorickettsioses ne peuvent expliquer les avortements observés chez le bétail de cette région. Il en est de même en ce qui concerne la brucellose. Un pourcentage assez élevé de sérums de bovins de la région de N'Gaoundéré répond positivement vis-à-vis de l'antigène néorickettsie Q18. Il en est de même pour les sérums d'hommes vivant en contact étroit avec ces animaux. Il n'a pas été possible d'établir de relations entre l'âge des bovins et la réponse sérologique de ceux-ci vis-à-vis des 5 antigènes majeur

Multi-input Multi-output Farm-level Cost Function: A Comparison of Least Squares and Entropy Estimators

We introduce a modification of the quadratic-Leontieff multi-output cost function that is particularly suitable for the data of the Farm Accountancy Data Network. We present least squares and entropy estimates of that function and compare their results for a sample of crop farms. Our results are encouraging for the use of entropy estimators in cases in which farms are not assumed to share the same technology. Our approach can be seen as an extension of the Positive Mathematical Programming approach (Howitt, 1995). The extension consists in an explicit specification of inputs in the cost function and in the possibility of modeling several farms simultaneously.cost function, least squares estimator, entropy estimator, heterogeneity, Farm Management, C3, D61, Q12,

Review : Auto-oxidation of aliphatic polyamides

The literature on oxidation kinetics of polyamides and model compounds has been reviewed in order to try to extract suitable information for non-empirical kinetic modeling. Polyamide characteristics are systematically compared to polyolefin ones, these latter being more extensively studied. From kinetic analysis point of view, it is shown that oxidation attacks predominantly a amino methylenes of which C eH bond is considerably weaker than the other methylenes. As a result, propagation by H abstraction is considerably faster in polyamides than in polyethylene for instance. Termination by radical combination is also very fast. Another cause of PA oxidizability is the instability of a amino hydroperoxides linked to the inductive effect of nitrogen. This instability is responsible for many key features of oxidation kinetics especially the absence of induction period. The main stable oxidation products are imides resulting from disproportionation processes meanwhile chain scissions resulting from rearrangements of a amino alkyls by b-scission are also significant process although their yield appears lower than in polyolefins

Helminthes des zébus adultes de la région de Maroua (Nord-Cameroun)

Une enquête menée à l'abattoir de Maroua (Nord-Cameroun) et portant sur 409 animaux de boucherie a permis de mettre en évidence sur le bétail autochtone 30 espèces différentes d'helminthes dont les mieux représentées sont: Dicrocoelium hospes (61,3 p. 100), Fasciola gigantica (31,3 p. 100), divers Paramphistomidae de la panse (52 p. 100), cinq Carmyerius (35,3 p. 100), Schistosoma bovis (28,8 p. 100), Cysticercus bovis (21 p. 100), de nombreux Trichostrongylidae (Haemoncus contortus, 52 p. 100; Cooperia pectinata et Cooperia punctata, 21 p. 100) et des Filaires (Artionema labiato-papillosa, 29,5 p. 100; Onchocerca armillata, 29,5 p. 100; Onchocerca gutturosa, 43,2 p. 100). Le parasitisme par Oesophagostomum radiatum, Bunostomum phlebotomum et les grands Cestodes de l'intestion grêle paraît assez modéré. Ces helminthes sont associés entre eux dans la quasi-totalité des cas et les associations sont graves, car elles mettent en jeu souvent six, huit et même neuf espèces dont certaines sont très pathogènes. Les auteurs comparent le parasistisme du zébu adulte nord-Camerounais au parasitisme global des zébus du Tchad et de R.C.A. (Bouar). Ils notent un accroissement sensible du taux d'infestation des animaux des zones sahéliennes (isohyète 300-500 mm) lorsqu'ils descendent pour abattage vers les régions plus humides (isohyète 800-900 mm

Etude dans certaines conditions africaines de l'action antiparasitaire du Thiabendazole sur divers helminthes des animaux domestiques. III. Nématodes du veau de lait

Lors des essais réalisés au Tchad et au Nord Cameroun, il a été constaté que le Thiabendazole, à la dose de 100 mg/kg, est capable de détruire l'ensemble des parasites intestinaux des veaux de lait, notamment Neoascaris vitulorum. Les doses les plus faibles (50-60 mg/kg), déjà efficaces, ne peuvent être recommandées, car l'élimination des Ascaris est trop lente d'où risque d'obstruction et d'intoxication mortelle. Les essais réalisés sur le terrain montrent que le gain de poids des animaux traités est importan

Effects of a flat rate introduction: shifts in farm activity and impact on farmers' income

Current thoughts on CAP changes, e.g. the "Health Check", emphasize the necessity to move away from payments based on historical receipts towards a "flatter rate" system. The aim of current research is to simulate the impact of a flat rate system (equal payments per hectare of cultivated land) compared to the current historical system (payments based on individual historic entitlements). Impact on production and income of arable, dairy and cattle farms of two different flat rate scenario's, is assessed with a farm-based sector model for Flanders. The model maximizes income at farm level, calibrated to observed farming behavior in 2001-2003. Farm data can be selected by farm type, size and region, simulations could be run for specific sub sectors, size classes or regions. In the two simulated flat rate scenario's subsectors will gain subsidies at the expense of other subsectors. However, farms can compensate a substantial part of their income loss by changing activity choice.Positive Mathematical Programming, farm model, Common Agricultural Policy, Payment Entitlements., Agricultural and Food Policy, Agricultural Finance, Farm Management, Research Methods/ Statistical Methods,

Multi-facetted impulsivity following nigral degeneration and dopamine replacement therapy.

Impulse control disorders (ICDs) are debilitating side effects of dopamine replacement therapy (DRT) in Parkinson's disease (PD) that severely affect the quality of life of patients. While DRT, the pattern and extent of neurodegeneration, and prodromic factors of vulnerability (e.g. impulsivity) have all been hypothesized to play a role in the development of ICDs, their respective, and potentially interacting, contributions remain to be established. High impulsive (HI), Intermediate (Int) or low impulsive (LI) rats were identified based on their performance in both a differential reinforcement of low rate of responding (DRL) and a fixed consecutive number (FCN) schedules, that operationalize two independent facets of impulsivity, waiting and action inhibition (motor impulsivity). We investigated whether high impulsivity trait influenced the progressive development of a parkinsonian state induced by viral-mediated overexpression of α-synuclein, and whether impulsivity trait and nigrostriatal neurodegeneration independently or jointly influenced the effects of DRT on impulse control. α-synuclein-induced nigrostriatal neurodegeneration increased both waiting and motor impulsivity. The D2/D3 dopamine receptor agonist pramipexole exacerbated motor impulsivity more than waiting. However, the pramipexole-induced increase in waiting impulsivity observed in both sham and lesioned rats, was more pronounced in HI lesioned rats, which displayed a restricted α-synuclein-induced dopaminergic neurodegeneration. Thus, a PD-like nigrostriatal lesion increases both motor and waiting impulsivity, but its interaction with a pre-existing impulsivity trait, which, at the cellular level, confers resilience to dopaminergic neurodegeneration, worsens the detrimental effects of D2/D3 dopamine receptor agonists on inhibitory control.This is the final published version. It first appeared at http://www.sciencedirect.com/science/article/pii/S0028390816302118