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Le projet TCP/MLI/3402 FAO intitulé « Appui à la lutte contre la mouche tsé-tsé et les trypanosomoses dans les cercles de Sikasso et Kadiolo, au Mali » a été crée pour appuyer le Projet de Lutte contre la Mouche tsé-tsé et les trypanosomoses (PLMT) dans ses efforts de contrôle des tsé-tsé et trypanosomes. Son objectif était de créer les conditions amenant l’état, les collectivités territoriales et les communautés villageoises à prendre en charge la lutte contre la trypanosomose et ses vecteurs de façon durable. Dans les cercles de Kadiolo (20 villages) et Sikasso (15 villages) 35 villages ont été prospectés. Pour cette étude 350 pièges biconiques Challier – Laveissière ont été posés dans les galeries et au niveau des points de contact des différents cours d’eau et géo référencés à l’aide de GPS. La prospection entomologique dans la zone de l’étude a permis la capture de deux espèces de glossines : Glossina palpalis gambiensis et Glossina tachinoïdes. Le nombre total de glossines capturées est 786 dont 405 mâles et 381 femelles. Parmi les glossines capturées, il ya 691 Glossina palpalis gambiensis dont 349 mâles et 342 femelles, 95 Glossina tachinoïdes dont 56 mâles et 39 femelles. Le sexe ratio est de 1,12, donc légèrement en faveur des mâles. Le taux d’infection des glossines qui concerne le cercle de Kadiolo seulement est 0%. La Densité Apparente de glossines par Piège et par jour (DAP) dans la zone du projet est 2,2.

Human population growth, climate change and economic development are causing major environmental modifications in Western Africa, which will have important repercussions on the epidemiology of sleeping sickness. A new initiative, the Atlas of human African trypanosomiasis (HAT), aims at assembling and geo-referencing all epidemiological data derived from both active screening activities and passive surveillance. A geographic database enables to generate up-to-date disease maps at a range of scales and of unprecedented spatial accuracy. We present preliminary results for seven West African countries (Benin, Burkina Faso, Côte d’Ivoire, Ghana, Guinea, Mali and Togo) and briefly discuss the relevance of the Atlas for future monitoring, control and research activities.

M3 reflection intensity ([I.sub.M3]) from tetanized, intact skeletal muscle fiber bundles was measured during sinusoidal length oscillations at 2.8 kHz, a frequency at which the myosin motor's power stroke is greatly reduced. [I.sub.M3] signals were approximately sinusoidal, but showed a 'double peak' distortion previously observed only at lower oscillation frequencies. A tilting lever arm model simulated this distortion, where [I.sub.M3] was calculated from the molecular structure of myosin subfragment 1 (S1). Simulations showed an isometric lever arm disposition close to normal to the filament axis at isometric tension, similar to that found using lower oscillation frequencies, where the power stroke contributes more toward total S1 movement. Inclusion of a second detached S1 in each actin-bound myosin dimer increased simulated [I.sub.M3] signal amplitude and improved agreement with the experimental data. The best agreement was obtained when detached heads have a fixed orientation, insensitive to length changes, and similar to that of attached heads at tetanus plateau. This configuration also accounts for the variations in relative intensity of the two main peaks of the M3 reflection substructure after a length change. This evidence of an [I.sub.M3] signal distortion when power stroke tilting is suppressed, provided that a large enough amplitude of length oscillation is used, is consistent with the tilting lever arm model of the power stroke. skeletal muscle; X-ray diffraction; muscle mechanics; molecular motors; subfragment 1 structure

Non-cross-bridge calcium-dependent stiffness in frog muscle fibers. Am J Physiol Cell Physiol 286: C1353-C1357, 2004. First published January 28, 2004; 10.1152/ajpcell.00493.2003.--At the end of the force transient elicited by a fast stretch applied to an activated frog muscle fiber, the force settles to a steady level exceeding the isometric level preceding the stretch. We showed previously that this excess of tension, referred to as 'static tension,' is due to the elongation of some elastic sarcomere structure, outside the cross bridges. The stiffness of this structure, 'static stiffness,' increased upon stimulation following a time course well distinct from tension and roughly similar to intracellular [Ca.sup.2+] concentration. In the experiments reported here, we investigated the possible role of [Ca.sup.2+] in static stiffness by comparing static stiffness measurements in the presence of [Ca.sup.2+] release inhibitors (D600, Dantrolene, [sup.2][H.sub.2]O) and cross-bridge formation inhibitors [2,3-butanedione monoxime (BDM), hypertonicity]. Both series of agents inhibited tension; however, only D600, Dantrolene, and [sup.2][H.sub.2]O decreased at the same time static stiffness, whereas BDM and hypertonicity left static stiffness unaltered. These results indicate that [Ca.sup.2+], in addition to promoting cross-bridge formation, increases the stiffness of an (unidentified) elastic structure of the sarcomere. This stiffness increase may help in maintaining the sarcomere length uniformity under conditions of instability. intact muscle fiber; static stiffness; tension inhibitors; titin

Biocrusts are key biotic components of arid and semi-arid ecosystems worldwide. In the semi-arid ecosystems of north-eastern Patagonia, the moss biocrust is present both beneath shrubs and in intershrub spaces. In this study we ran a series of field and greenhouse trials aimed at quantifying the moss biocrust cover at sites that differed in grazing and/or shrub mechanical (chaining) disturbance and evaluating its seed entrapping capacity, and its effect on the superficial water balance and grass seedling growth. Grazing or the combined effect of grazing and chaining impacted negatively on the moss biocrust cover. The presence of moss biocrust facilitated seed entrapment and increased the seed density of perennial grasses in the soil seed bank, improved the superficial water balance, and enhanced grass seedling growth. In conclusion, in the semi-arid shrublands in north-eastern Patagonia, the moss biocrust appeared vulnerable to grazing and shrub mechanical disturbance, and it showed functional roles that may facilitate seedling establishment for perennial grasses. [ABSTRACT FROM AUTHOR]

Time-resolved lattice spacing were measured (10-millisecond time resolution) by x-ray diffraction of synchrotron radiation in single intact muscle fibers of the frog Rana temporaria undergoing electrically stimulated tension development during [...]

Pesticides can help reduce yield losses caused by pests, pathogens, and weeds, but their overuse causes serious environmental pollution. They are persistent in the environment and are biomagnified through the food chain, becoming a serious health hazard for humankind. Bioremediation, where microbes are used to degrade pesticides in situ, is a useful technology. This review summarizes data on the fungi involved in the biodegradation of chemical pesticides and their application in soil and water bioremediation. Indications for future studies in this field are given. [ABSTRACT FROM AUTHOR]

Background: Trypanocidal drugs have been used to control African animal trypanosomosis for several decades. In Ethiopia, these drugs are available from both authorized (legal) and unauthorized (illegal) sources but documentation on utilization practices and quality of circulating products is scanty. This study looked at the practices of trypanocidal drug utilization by farmers and the integrity of active ingredient in trypanocides sold in Gurage zone, south western Ethiopia. The surveys were based on a structured questionnaire and drug quality determination of commonly used brands originating from European and Asian companies and sold at both authorized and unauthorized markets. One hundred farmers were interviewed and 50 drug samples were collected in 2013 (Diminazene aceturate = 33 and Isometamidium chloride = 17; 25 from authorized and 25 from unauthorized sources). Samples were tested at the OIE-certified Veterinary Drug Control Laboratory (LACOMEV) in Dakar, Senegal, by using galenic standards and high performance liquid chromatography. Results: Trypanosomosis was found to be a major threat according to all interviewed livestock keepers in the study area. Diminazene aceturate and isometamidium chloride were preferred by 79% and 21% of the respondents respectively, and 85% of them indicated that an animal receives more than six treatments per year. About 60% of these treatments were reported to be administered by untrained farmers. Trypanocidal drug sources included both unauthorized outlets (56%) and authorized government and private sources (44%). A wide availability and usage of substandard quality drugs was revealed. Twenty eight percent of trypanocidal drugs tested failed to comply with quality requirements. There was no significant difference in the frequency of non-compliance between diminazene-based and isometamidium chloride products (P = 0.87) irrespective of the marketing channel (official and unofficial). However, higher rates of non-compliant trypanocides were detected for drugs originating from Asia than from Europe (P = 0.029). Conclusion: The findings revealed the presence of risk factors for the development of drug resistance, i.e. wide distribution of poor quality drugs as well as substandard administration practices. Therefore, it is strongly recommended to enforce regulatory measures for quality control of veterinary drugs, to expand and strengthen veterinary services and to undertake trypanocidal drug efficacy studies of wider coverage. [ABSTRACT FROM AUTHOR]

Aspergillus sydowii is a cosmopolitan fungus that has been responsible for the mass destruction of coral in the Caribbean Sea over the last 15 years. To our knowledge, this study has found the first case of A. sydowii in the Mediterranean Sea, in marine-bottom sediments, water and calcareous shells of bivalve molluscs sampled during a campaign to characterise the mycobiota in the Port of Genoa (Italy). The area is characterised by adverse environmental conditions (high turbidity, organic pollution and high concentrations of phosphorus and nitrogen compounds). These parameters, in combination with a rising temperature, could contribute to A. sydowii bloom and dispersal. This fungal strain may have been imported into the Port of Genoa in the bilge water of vessels or by torrent input. This work represents the first step in the implementation of a monitoring programme to safeguard calcareous sponges and sea fan corals endemic in the Mediterranean Sea. [ABSTRACT FROM AUTHOR]

Key points Actomyosin ATP hydrolysis occurring during muscle contraction releases inorganic phosphate [Pi] in the myoplasm. High [Pi] reduces force and affects force kinetics in skinned muscle fibres at low temperature. These effects decrease at high temperature, raising the question of their importance under physiological conditions., This study provides the first analysis of the effects of Pi on muscle performance in intact mammalian fibres at physiological temperature. Myoplasmic [Pi] was raised by fatiguing the fibres with a series of tetanic contractions., [Pi] increase reduces muscular force mainly by decreasing the force of the single molecular motor, the crossbridge, and alters the crossbridge response to fast length perturbation indicating faster kinetics., These results are in agreement with schemes of actomyosin ATPase and the crossbridge cycle including a low- or no-force state and show that fibre length changes perturb the Pi-sensitive force generation of the crossbridge cycle., Abstract Actomyosin ATP hydrolysis during muscle contraction releases inorganic phosphate, increasing [Pi] in the myoplasm. Experiments in skinned fibres at low temperature (10-12°C) have shown that [Pi] increase depresses isometric force and alters the kinetics of actomyosin interaction. However, the effects of Pi decrease with temperature and this raises the question of the role of Pi under physiological conditions. The present experiments were performed to investigate this point. Intact fibre bundles isolated from the flexor digitorum brevis of C57BL/6 mice were stimulated with a series of tetanic contractions at 1.5 s intervals at 33°C. As show previously the most significant change induced by a bout of contractile activity similar to the initial 10 tetani of the series was an increase of [Pi] without significant Ca2+ or pH changes. Measurements of force, stiffness and responses to fast stretches and releases were therefore made on the 10th tetanus of the series and compared with control. We found that (i) tetanic force at the 10th tetanus was ∼20% smaller than control without a significant decrease of crossbridge stiffness; and (ii) the force recovery following quick stretches and releases was faster than in control. These results indicate that at physiological temperature the increase of [Pi] occurring during early fatigue reduces tetanic force mainly by depressing the individual crossbridge force and accelerating crossbridge kinetics. [ABSTRACT FROM AUTHOR]

Fungi include a vast group of eukaryotic organisms able to colonise different natural, anthropised and extreme environments, including marine areas contaminated by metals. The present study aims to give a first multidisciplinary characterisation of marine bottom sediments contaminated by metals (Cd, Co, Cr, Cu, Ni, and Zn), originating in the water leakage from an abandoned Fe-Cu sulphide mine (Libiola, north-western Italy), and evaluate how the chemical and physical parameters of water and sediments may affect the benthic fungal communities. Our preliminary results showed the high mycodiversity of the marine sediments studied (13 genera and 23 species of marine fungi isolated), and the great physiological adaptability that this mycobiota evolved in reaction to the effects of the ecotoxic bottom sediment contamination, and associated changes in the seawater parameters. [ABSTRACT FROM AUTHOR]

Discovering brain activity patterns associated with specific stimuli, behaviors, or mental disorders is a primary objective of many neuroimaging studies. In particular, functional magnetic resonance imaging analyses are often concerned with finding brain areas "most relevant" to a mental state of interest. In this paper, we consider the predictive accuracy of a subset of voxels (smallest units of a threedimensional image) identified by multivariate sparse regression as a better relevance measure than the commonly used mass-univariate correlations between the task and individual voxels. Sparse regression detects synergistic multivoxel interactions missed by univariate techniques. Moreover, when invoked iteratively, it allows us to discover novel patterns of information distribution through the brain. Indeed, unlike univariate techniques that typically imply a sharp transition from task-relevant to task-irrelevant brain areas, our approach reveals that for some tasks, task-relevant information is distributed rather "holographically" through the entire brain, yielding multiple relevant subsets of voxels, with gradually declining predictive accuracy, and without any clear separation between taskrelevant and task-irrelevant ones. Interestingly, as our preliminary results show, such phenomena occur in certain "complex" experiences such as pain perception, but not in relatively "simple" tasks such as finger tapping. [ABSTRACT FROM AUTHOR]

We describe recent preliminary studies demonstrating that computational analysis of spoken and written language can provide for highly accurate diagnostics over a wide variety of psychiatric and neurologic conditions, including psychosis, drug abuse, Parkinson's, and Alzheimer's. These results are based on the mathematical formalization of psychiatric qualitative knowledge related to the characterization of the conditions (e.g., "derailment" in psychosis) and drug effects (e.g., increased intimacy/affection with the use of the recreational drug ecstasy), as well as novel linguistic feature extraction approaches. Moreover, we show novel results using publicly available text sources suggesting that 1) it is possible to define an embedding space that allows modeling of the vast language dimension into a smaller space to map and compare different conditions, and 2) computational studies of a public personality (Ronald Reagan) can likely yield novel insights into normal aging and neurodegenerative disorders. Finally, we discuss the implications for mental health (and possibly, computer science) of a systematic application of this methodology, extended to include similar readily available behavioral data such as voice and video. [ABSTRACT FROM AUTHOR]

BackgroundLanguage use is of increasing interest in the study of mental illness. Analytical approaches range from phenomenological and qualitative to formal computational quantitative methods. Practically, the approach may have utility in predicting clinical outcomes. We harnessed a real-world sample (blog entries) from groups with psychosis, strong beliefs, odd beliefs, illness, mental illness and/or social isolation to validate and extend laboratory findings about lexical differences between psychosis and control subjects.MethodWe describe the results of two experiments using Linguistic Inquiry and Word Count software to assess word category frequencies. In experiment 1, we compared word use in psychosis and control subjects in the laboratory (23 per group), and related results to subject symptoms. In experiment 2, we examined lexical patterns in blog entries written by people with psychosis and eight comparison groups. In addition to between-group comparisons, we used factor analysis followed by clustering to discern the contributions of strong belief, odd belief and illness identity to lexical patterns.ResultsConsistent with others’ work, we found that first-person pronouns, biological process words and negative emotion words were more frequent in psychosis language. We tested lexical differences between bloggers with psychosis and multiple relevant comparison groups. Clustering analysis revealed that word use frequencies did not group individuals with strong or odd beliefs, but instead grouped individuals with any illness (mental or physical).ConclusionsPairing of laboratory and real-world samples reveals that lexical markers previously identified as specific language changes in depression and psychosis are probably markers of illness in general. [ABSTRACT FROM PUBLISHER]

The Old World screwworm (OWS) fly, Chrysomya bezziana, is an obligate parasite of livestock, and the myiasis caused by its larval infestations is economically important in Indonesia. The current spatial distribution of such a pest depends on two main factors: the current environmental conditions in which it can survive; and, its ability to occupy those environments by dispersal, which can be inferred from phylogeography and population genetics. These indicate that all OWS flies in Indonesia have mitochondrial cytochrome b (cyt b) haplotypes of the Asian lineage, and the regional separation of its four sub-lineages is the result of infrequent long-distance dispersal. We report the first investigation to associate regional cyt b sub-lineages of the OWS fly with environmental variables. Principal Components Analysis was used to demonstrate that these sub-lineages are associated with very similar macro-climates throughout Indonesia. Then, a species distribution model for the OWS fly in Indonesia was obtained by using the Maxent program. This indicated that elevation captured information not given by other environmental variables, and cattle density provided the most useful information by itself. The results of our study provide some important leads for future research, which will require better, stratified sampling. [ABSTRACT FROM AUTHOR]

Tsetse flies, like many insects, use pheromones for inter- and intra-specific communication. Several of their pheromones are cuticular hydrocarbons (CHCs) that are perceived by contact at close range. We hypothesized that for a successful implementation of the Sterile Insect Technique (SIT), along with proper identification of target area and target species, the target tsetse populations and the sterile flies must chemically communicate with each other. To study the population structuring of Glossina pallidipes in Ethiopia, CHCs were extracted and analyzed from three tsetse belts. As a comparative approach, wing morphometric analysis was performed. The analysis of the relative abundance of CHCs revealed that populations of G. pallidipes from the Rift Valley tsetse belt showed a distinct clustering compared to populations from the other two belts. The spatial pattern of CHC differences was complemented by the wing morphometric analysis. Our data suggest that CHCs of known biological and ecological role, when combined with wing morphometric data, will provide an alternative means for the study of population structuring of Glossina populations. This could aid the planning of area wide control strategies using SIT, which is dependent on sexual competence. [ABSTRACT FROM AUTHOR]

ABSTRACT Vegetation in many arid and semi-arid shrublands frequently occurs in patches with high plant cover (shrub patches) interspersed in a low-cover herbaceous matrix (inter-shrub areas). We hypothesized that (a) livestock grazing is an important determinant of such spatial patterns of vegetation, and (b) redistribution of soil resources associated with shrub patches helps in the recovery of vegetation in inter-shrub areas. To test these hypotheses, we (a) used line transects to compare spatial variations in vegetation, soil microtopography, and soil physicochemical properties in grazed areas and areas protected from grazing since 1970, (b) added sediment and seeds to inter-shrub areas, and (c) measured resource redistribution after a wildfire. Results were consistent with the hypotheses. They indicated greater spatial heterogeneity in vegetation, soil microtopography and soil physicochemical properties in grazed areas than in protected areas, and that addition of sediment and seeds or redistribution of soil resources from shrub patches after a wildfire enhanced re-establishment of vegetation in degraded inter-shrub areas. As a synthesis, a conceptual model of degradation and recovery processes in semi-arid shrublands of Northern Patagonia is presented. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The cultural evolution of introspective thought has been recognized to undergo a drastic change during the middle of the first millennium BC. This period, known as the "Axial Age," saw the birth of religions and philosophies still alive in modern culture, as well as the transition from orality to literacy-which led to the hypothesis of a link between introspection and literacy. Here we set out to examine the evolution of introspection in the Axial Age, studying the cultural record of the Greco-Roman and Judeo-Christian literary traditions. Using a statistical measure of semantic similarity, we identify a single "arrow of time" in the Old and New Testaments of the Bible, and a more complex non-monotonic dynamics in the Greco-Roman tradition reflecting the rise and fall of the respective societies. A comparable analysis of the twentieth century cultural record shows a steady increase in the incidence of introspective topics, punctuated by abrupt declines during and preceding the First and Second World Wars. Our results show that (a) it is possible to devise a consistent metric to quantify the history of a high-level concept such as introspection, cementing the path for a new quantitative philology and (b) to the extent that it is captured in the cultural record, the increased ability of human thought for self-reflection that the Axial Age brought about is still heavily determined by societal contingencies beyond the orality-literacy nexus. [ABSTRACT FROM AUTHOR]