Apport de la télédétection à la cartographie de l’évolution spatio-temporelle de la dynamique de l’occupation du sol dans la région des Lacs (Centre de la Côte d’Ivoire)

L’objectif de cet article est la cartographie de l’évolution spatio-temporelle de l’occupation du sol dans la région des Lacs (Côte d’Ivoire) à partir des données de télédétection (images Landsat TM et ETM+) sur une période de 16 ans (1986-2002) d’une part, et l’impact de cette occupation sur les coefficients de rétention d’autre part. Une analyse diachronique des données satellitaires a été réalisée et l’approche de la classification supervisée à partir des compositions colorées des bandes a été retenue en vue de la discrimination des classes. Les précisions globales obtenues pour les images classifiées sont de 88,47% (1986) et de 90,46% (2002). Les indices de Kappa sont de 85,84% (1986) et 88 % (2002). L’étude de la dynamique spatio-temporelle de l’occupation du sol de 1986 à 2002 fait apparaitre des taux moyens annuels calculés de régression pour les plans d’eau de -0,164, les cultures irriguées -0,231 et la savane -1,063. On observe parallèlement une progression des classes forêt (0,287), cultures (0,473) et sols nus ou dégradés (0,699). Les coefficients de rétention calculés sont faibles. En conséquence, cette étude montre que la zone d’étude est marquée par une forte anthropisation et une dégradation des conditions pluviométriques qui ont fortement affecté le mode d’occupation du sol.Mots-clés : télédétection, dynamique, occupation du sol, région des Lacs, Côte d’Ivoire

A community integrated concept that minimises death of most vulnerable neonates at poor-resource environments

Introduction: Highest proportion of most vulnerable Nigeria neonates are concentrated in hard-to-reach local villages without proper intervention devices owing to unavailable electric power. Hence, majority of needy neonates continue to lose their lives due to their inability to journey to urban cities where few inadequately equipped neonatal intervention centres are located. The Nigerian healthcare system requires the neonates to make the often-treacherous journeys, travelling into the cities in search of possible intervention. This system has continued to fail generations of precious neonates who could have survived otherwise. It is therefore imperative to device a technique that could enable the reversal of the patient traffic – by “taking our medicine to them right where they are" instead of waiting for them to come to our medicine right where we are at urban locations. Methods: Solar-based applicable devices and simplified neonatal intervention procedures operable by basic medical and nursing officers were developed. The technologies were fundamentally tailored for maintainability by the local people. This empowers the confidence of treating many of the regular neonatal emergencies at primary healthcare centre located within the villages. Uncomplicated treatable cases are believed to constitute over 65% of all cases and hence could be adequately supported. Appropriately remanufactured tricycle was modified to operate ambulatory services for referring the cases requiring specialist care in the city. Conclusion: Successful implementation of this concept and its scale-up could guarantee over 75% reduction of neonatal mortality within a controlled geographical region

Actin cortex architecture regulates cell surface tension

Animal cell shape is largely determined by the cortex, a thin actin network underlying the plasma membrane in which myosin-driven stresses generate contractile tension. Tension gradients result in local contractions and drive cell deformations. Previous cortical tension regulation studies have focused on myosin motors. Here, we show that cortical actin network architecture is equally important. First, we observe that actin cortex thickness and tension are inversely correlated during cell-cycle progression. We then show that the actin filament length regulators CFL1, CAPZB and DIAPH1 regulate mitotic cortex thickness and find that both increasing and decreasing thickness decreases tension in mitosis. This suggests that the mitotic cortex is poised close to a tension maximum. Finally, using a computational model, we identify a physical mechanism by which maximum tension is achieved at intermediate actin filament lengths. Our results indicate that actin network architecture, alongside myosin activity, is key to cell surface tension regulation

Carbonate Anion Radical Generated by the Peroxidase Activity of Copper-Zinc Superoxide Dismutase:Scavenging of Radical and Protection of Enzyme by Hypotaurine and Cysteine Sulfinic Acid

Copper-zinc superoxide dismutase (SOD) is considered one of the most important mammalian antioxidant defenses and plays a relevant role due to its main function in catalyzing the dismutation of superoxide anion to oxygen and hydrogen peroxide. However, interaction between SOD and H2O2 produced a strong copper-bound oxidant (Cu(II)●OH) that seems able to contrast the self-inactivation of the enzyme or oxidize other molecules through its peroxidase activity. The bicarbonate presence enhances the peroxidase activity and produces the carbonate anion radical (CO3●–). CO3●– is a freely diffusible reactive species capable of oxidizing several molecules that are unwieldy to access into the reactive site of the enzyme. Cu(II)●OH oxidizes bicarbonate to the CO3●–, which spreads out of the binding site and oxidizes hypotaurine and cysteine sulfinic acid to the respective sulfonates through an efficient reaction. These findings suggest a defense role for sulfinates against the damage caused by CO3●–. The effect of hypotaurine and cysteine sulfinic acid on the CO3●–-mediated oxidation of the peroxidase probe ABTS to ABTS cation radical (ABTS●+) has been studied. Both sulfinates are able to inhibit the oxidation of ABTS mediated by CO3●–. The effect of hypotaurine and cysteine sulfinic acid against SOD inactivation by H2O2 (~42% protection of enzyme activity) has also been investigated. Interestingly, hypotaurine and cysteine sulfinic acid partially avoid the H2O2-mediated SOD inactivation, suggesting that the two sulfinates may have access to the SOD reactive site and preserve it by reacting with the copper-bound oxidant. In this way hypotaurine and cysteine sulfinic acid not only intercept CO3●–which could move out from the reactive site and cause oxidative damage, but also prevents the inactivation of SOD

Life-cycle and host preference of Amblyomma ovale (Acari: Ixodidae) under laboratory conditions

This study evaluated for the first time the life cycle of Amblyomma ovale in the laboratory. For this purpose, larvae and nymphs were exposed to Gallus gallus (chickens), Cavia porcellus (guinea pigs), Rattus norvegicus (wistar rats), Oryctolagus cuniculus (domestic rabbits), Calomys callosus (vesper mouse), and Didelphis albiventris (white-eared opossum). Nymphs were also exposed to Nectomys squamipes (South American water rat). Adult ticks were fed on dogs. The life-cycle of A. ovale in laboratory could be completed in an average period of ca. 190 days, considering prefeeding periods of 30 days for each of the parasitic stages. Vesper mice were the most suitable host for A. ovale larvae, whereas water rats were the most suitable host for A. ovale nymphs. Our results, coupled with literature data, strongly indicate that small rodents have an important role in the life history of A. ovale. Chickens (the only avian host used in the present study) showed to be moderately suitable hosts for subadult A. ovale ticks, indicating that wild birds might have a secondary role in the life history of A. ovale. Domestic dogs showed to be highly suitable for the adult stage of A. ovale, in agreement with literature data that indicate that the domestic dog is currently one of the most important hosts of A. ovale adult ticks in Latin America.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq

Two experiments for the price of one? -- The role of the second oscillation maximum in long baseline neutrino experiments

We investigate the quantitative impact that data from the second oscillation maximum has on the performance of wide band beam neutrino oscillation experiments. We present results for the physics sensitivities to standard three flavor oscillation, as well as results for the sensitivity to non-standard interactions. The quantitative study is performed using an experimental setup similar to the Fermilab to DUSEL Long Baseline Neutrino Experiment (LBNE). We find that, with the single exception of sensitivity to the mass hierarchy, the second maximum plays only a marginal role due to the experimental difficulties to obtain a statistically significant and sufficiently background-free event sample at low energies. This conclusion is valid for both water Cherenkov and liquid argon detectors. Moreover, we confirm that non-standard neutrino interactions are very hard to distinguish experimentally from standard three-flavor effects and can lead to a considerable loss of sensitivity to \theta_{13}, the mass hierarchy and CP violation.Comment: RevTex 4.1, 23 pages, 10 figures; v2: Typos corrected, very minor clarifications; matches published version; v3: Fixed a typo in the first equation in sec. III

SPIN90 associates with mDia1 and the Arp2/3 complex to regulate cortical actin organization

Cell shape is controlled by the submembranous cortex, an actomyosin network mainly generated by two actin nucleators: the Arp2/3 complex and the formin mDia1. Changes in relative nucleator activity may alter cortical organization, mechanics and cell shape. Here we investigate how nucleation-promoting factors mediate interactions between nucleators. In vitro, the nucleation-promoting factor SPIN90 promotes formation of unbranched filaments by Arp2/3, a process thought to provide the initial filament for generation of dendritic networks. Paradoxically, in cells, SPIN90 appears to favour a formin-dominated cortex. Our in vitro experiments reveal that this feature stems mainly from two mechanisms: efficient recruitment of mDia1 to SPIN90-Arp2/3 nucleated filaments and formation of a ternary SPIN90-Arp2/3-mDia1 complex that greatly enhances filament nucleation. Both mechanisms yield rapidly elongating filaments with mDia1 at their barbed ends and SPIN90-Arp2/3 at their pointed ends. Thus, in networks, SPIN90 lowers branching densities and increases the proportion of long filaments elongated by mDia1

The epidemiology of injuries across the weight-training sports

Background: Weight-training sports, including weightlifting, powerlifting, bodybuilding, strongman, Highland Games, and CrossFit, are weight-training sports that have separate divisions for males and females of a variety of ages, competitive standards, and bodyweight classes. These sports may be considered dangerous because of the heavy loads commonly used in training and competition. Objectives: Our objective was to systematically review the injury epidemiology of these weight-training sports, and, where possible, gain some insight into whether this may be affected by age, sex, competitive standard, and bodyweight class. Methods: We performed an electronic search using PubMed, SPORTDiscus, CINAHL, and Embase for injury epidemiology studies involving competitive athletes in these weight-training sports. Eligible studies included peer-reviewed journal articles only, with no limit placed on date or language of publication. We assessed the risk of bias in all studies using an adaption of the musculoskeletal injury review method. Results: Only five of the 20 eligible studies had a risk of bias score ≥75 %, meaning the risk of bias in these five studies was considered low. While 14 of the studies had sample sizes >100 participants, only four studies utilized a prospective design. Bodybuilding had the lowest injury rates (0.12–0.7 injuries per lifter per year; 0.24–1 injury per 1000 h), with strongman (4.5–6.1 injuries per 1000 h) and Highland Games (7.5 injuries per 1000 h) reporting the highest rates. The shoulder, lower back, knee, elbow, and wrist/hand were generally the most commonly injured anatomical locations; strains, tendinitis, and sprains were the most common injury type. Very few significant differences in any of the injury outcomes were observed as a function of age, sex, competitive standard, or bodyweight class. Conclusion: While the majority of the research we reviewed utilized retrospective designs, the weight-training sports appear to have relatively low rates of injury compared with common team sports. Future weight-training sport injury epidemiology research needs to be improved, particularly in terms of the use of prospective designs, diagnosis of injury, and changes in risk exposure

Communicating product user reviews and ratings in interfaces for e-commerce: a multimodal approach

This paper describes a comparative empirical evaluation study that uses multimodal presentations to communicate review messages in an e-commerce platform. Previous studies demonstrate the effective use of multimodality in different problem domains (e.g. e-learning). In this paper, multimodality and expressive avatars are used to communicate information related to product reviews messages. The data of the reviews was opportunistically collected from Facebook and Twitter. Two independent groups of users were used to evaluate two different presentations of reviews and ratings using as a basis an experimental e- commerce platform. The control group used a text-based with emojis presentation and the experimental group used a multimodal approach based on expressive avatars. Three parameters of usability were measured. These were efficiency, effectiveness, user satisfaction, and user preference. The result showed that the two approaches performed similarly. These findings provide a basis for further experiments in which text, emojis and expressive avatars can be combine to communicate a larger volume of reviews and ratings