FOLLOW UP IN LARGE BOWEL RESECTIONS: WERNICKE-KORSAKOFF'S SYNDROME

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A structural model for (GlcNAc)2 translocation via a periplasmic chitooligosaccharide-binding protein from marine Vibrio bacteria

VhCBP is a periplasmic chitooligosaccharide-binding protein mainly responsible for translocation of the chitooligosaccharide (GlcNAc)2 across the double membranes of marine bacteria. However, structural and thermodynamic understanding of the sugar-binding/-release processes of VhCBP is relatively less. VhCBP displayed the greatest affinity toward (GlcNAc)2, with lower affinity for longer-chain chitooligosaccharides [(GlcNAc)3–4]. (GlcNAc)4 partially occupied the closed sugar-binding groove, with two reducing-end GlcNAc units extending beyond the sugar-binding groove and barely characterized by weak electron density. Mutation of three conserved residues (Trp363, Asp365, and Trp513) to Ala resulted in drastic decreases in the binding affinity toward the preferred substrate (GlcNAc)2, indicating their significant contributions to sugar binding. The structure of the W513A–(GlcNAc)2 complex in a ‘half-open’ conformation unveiled the intermediary step of the (GlcNAc)2 translocation from the soluble CBP in the periplasm to the inner membrane–transporting components. Isothermal calorimetry data suggested that VhCBP adopts the high-affinity conformation to bind (GlcNAc)2, while its low-affinity conformation facilitated sugar release. Thus, chitooligosaccharide translocation, conferred by periplasmic VhCBP, is a crucial step in the chitin catabolic pathway, allowing Vibrio bacteria to thrive in oceans where chitin is their major source of nutrients

FOLLOW UP IN LARGE BOWEL RESECTIONS: WERNICKE-KORSAKOFF'S SYNDROME

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Morphometric characterization of parasite Varroa sp. of bee Apis Mellifera L. in Benin

Open Access JournalVarroa sp. is one of the most important pests of world of bees A. mellifera Linnaeus (Hymenoptera: Apidae). The aim of this study is to analyze the morphological variability of Varroa so as to identify the different morphotypes of V. destructor. The study was conducted in 24 localities and 24 municipalities located in three regions (North-East, North-West and the Centre) of Benin. One to two hives were randomly selected per locality for collecting samples. In total 46 Varroa were examined in this study. Analysis of variance components was used to determine the share of the variability of morphological characteristics of V. destructor based on localities and climatic zones. Numerical classification was performed to group the populations of V. destructor based on morphological descriptors. The results show that the variability of morphological descriptors of V. destructor is usually larger at the community level than in climatic zones. In total four morphotypes of V. destructor are distinguished in Benin through the 4 variables used in the study

Anisotropic fragmentation in low-energy dissociative recombination

On a dense energy grid reaching up to 75 meV electron collision energy the fragmentation angle and the kinetic energy release of neutral dissociative recombination fragments have been studied in a twin merged beam experiment. The anisotropy described by Legendre polynomials and the extracted rotational state contributions were found to vary on a likewise narrow energy scale as the rotationally averaged rate coefficient. For the first time angular dependences higher than 2$^{nd}$ order could be deduced. Moreover, a slight anisotropy at zero collision energy was observed which is caused by the flattened velocity distribution of the electron beam.Comment: 8 pages, 4 figures; The Article will be published in the proceedings of DR 2007, a symposium on Dissociative Recombination held in Ameland, The Netherlands (18.-23. July 2008); Reference 19 has been published meanwhile in S. Novotny, PRL 100, 193201 (2008

Evidence of Polarons and Bipolarons in a Chemically Pressurized Nanoparticle Bi2Ba2Tb0.5Cu2O4+y

Previous researches on underdoped and overdoped Bi-2212 superconductor have shown that its mechanism follows the polarons-bipolarons theory of superconductivity. In this study, a chemically pressurized Bi-2212 compounds was synthesized and characterized. It was observed that phase analysis reveals the unique route of electron flow within the polycrystalline sample. The transmission electron microscopy (TEM) shows the presence of static and dynamic localizations that proves the possibly presence of Bose-Einstein condensation of inter-site bipolarons. This study on chemically pressurized Bi2Ba2Tb0.5Cu2O4+y compound has shown that the generation and dynamics of polarons and bipolarons are associated to the pentavalent post-transition nature of bismuth

Farmers' perception of climate change and climate-smart agriculture in northern Benin, west Africa

Climate-Smart Agriculture (CSA) is an approach that identifies actions needed to transform and reorganize agricultural systems to effectively support agricultural development and ensure food security in the face of climate change. In this study, we assessed farmers’ perception of climate change, available CSA practices (CSAP) and the determinants of CSAP adoption in northern Benin. A list of CSAP was generated from a workshop with different stakeholders. Face-to-face interviews were then carried out with 368 farmers selected based on stratified random sampling in the study area. Binomial generalized mixed-effect models were run to analyze the relation between socio-demographic characteristics and the use of CSAP. CSAP were evaluated using a three-point Likert scale and the frequency of agreement with the statement that the selected practices meet the pillars of CSA. More than 60% of farmers had heard about climate change, and more than 80% had observed changes in temperature, rainfall amounts and distribution. Thirty-one CSAP were identified in the area, and only 11 were known by more than 50% of farmers. Out of the 12 selected CSAP for the assessment of adoption and evaluation, seven (7) were used by more than 50% of those who knew them. Farmers agreed with the statements that the evaluated practices improved farm productivity and adaptation to climate change but did not mitigate climate change. Ethnic group and education level were the two major factors that significantly determined the use of the evaluated CSAP

Impact of CS-IPM on key social welfare aspects of smallholder farmers' livelihoods

Open Access JournalAll stakeholders, especially households that depend on agriculture, must come up with every avenue available to improve farm productivity in order to raise yields due to the constraints posed by climate change on food production systems. Sufficient increments in yields will address the challenges of food insecurity and malnutrition among vulnerable households, especially smallholder ones. Yield increases can be achieved sustainably through the deployment of various Climate Smart Integrated Pest Management (CS-IPM) practices, including good agronomic practices. Therefore, CS-IPM practices could be essential in ensuring better household welfare, including food security and nutrition. With such impact empirically documented, appropriate policy guidance can be realized in favor of CS-IPM practices at scale, thus helping to achieve sustainable food security and food systems. However, to this end, there is yet limited evidence on the real impact of CS-IPM practices on the various core social welfare household parameters, for instance, food security, household incomes, gender roles, and nutrition, among others. We contribute to this body of literature in this paper by reviewing various empirical evidence that analyzes the impact of respective CS-IPM practices on key social welfare aspects of smallholder farm households in developing countries around the world. The review finds that CS-IPM practices do increase households’ adaptation to climate change, thus enhancing soil and crop productivity, thereby ensuring food and nutrition security, as well as increasing market participation of CS-IPM adopters, thus leading to increased household incomes, asset accumulation, and subsequently better household food and nutrition security via direct own-farm produce consumption and market purchases using income. CS-IPM practices also enhance access to climate-related information, reduce greenhouse gas emissions, conserve biodiversity, and enhance dietary diversity through improved crop and livestock varieties and also reduce variable farm production costs. Therefore, there would be multiple welfare gains if CS-IPM practices were scaled up

Modeling Evolution of Resistance by Maruca vitrata (Lepidoptera: Crambidae) to Transgenic Insecticidal Cowpea in Africa

We created a detailed model of the Maruca vitrata (F.) and cowpea [Vigna unguiculata (L.) Walp] system to study the possible evolution of resistance by the insect to transgenic insecticidal cowpea, which is under development. We focused on population dynamics and genetics in a region of west Africa. We simulated single-toxin and pyramided (two-toxin) cowpea and emphasized conservative, worst-case scenarios in our analysis. The results indicate that as long as a pyramided, transgenic cowpea can be developed, seed saving by farmers and reliance on natural refuge are not major problems for resistance management. Furthermore, it is possible that one or both toxins in the pyramid may not need to be high dose for evolution to be delayed significantly (>20 yr or 80 generations for resistance to become a concern if transgenic cowpea is deployed in areas where M. vitrata is endemic). If efforts are made to deploy transgenic cowpea only into the regions where M. vitrata is not endemic, then there is little to no concern with resistance emerging in the M. vitrata populatio