Les determinants de choix de L'irrigation localisee par les Exploitants de la mitidja

Depuis les années 2000, les pouvoirs publics visent à encourager la mise en place des technologies  d’irrigation économes en eau. Le présent article cherche à expliquer les comportements des exploitants en matière d’adoption de nouvelles technologies d’irrigation. La modélisation de l'adoption de l'irrigation  localisée est retenue comme le cadre méthodologique du travail. Elle consiste à définir les facteurs qui déterminent l’adoption de l’irrigation localisée par les exploitants de la Mitidja. Dans ce sens, une enquête a été réalisée sur un échantillon de 117 exploitants tirés d’une manière aléatoire dans le périmètre irrigué de la Mitidja Ouest tranche 1. Les résultats obtenus mettent en évidence le rôle déterminant du type de culture pratiquée, le coût d’investissement, la subvention à l’irrigation  localisée, le niveau d’instruction, l’âge et la vulgarisation dans  l’adoption de l’irrigation localisée. En revanche l’adhésion à une association des irrigants, le statut de l’exploitation agricole, le prix de l’eau publique, l’accès à l’eau de la nappe par un forage, sont des facteurs qui n’interviennent pas dans le choix de ce type d’irrigation.MOTS CLES: Agriculture irriguée, périmètre Mitidja Ouest tranche 1, adoption technologique, irrigation localisée, modèle Logit Binomial

Molecular docking studies for the identifications of novel antimicrobial compounds targeting of staphylococcus aureus

This work  include several advanced molecular docking tools to study the interactions of our newly synthesized 1,3,4-thiadiazole  derivatives in the active site of penicillin binding protein and DNA gyrase against Staphylococcus aureus, the enzymes targeted for antimicrobial agents. Results such as MolDock scores, binding energies, residue binding distances, etc. were identified and discussed in this present research. The molecules with best docking results were selected in order to calculate drug likeness and bioavailability using Molinspiration software. All the compounds obey Lipinski’s rule and its extension and showed drug likeness. The pharmacokinetic parameters study was done using the AdmetSAR to display ADME and toxicity properties of these antimicrobial

An Efficient Green Photo-Fenton System for the Degradation of Organic Pollutants. Kinetics of Propranolol Removal From Different Water Matrices

Financiado para publicación en acceso aberto: Universidade da Coruña/CISUG[Abstract] We report on the degradation of aqueous propranolol (PRO) in a heterogeneous system with natural iron oxide (N.I.O.) and oxalic acid (OAA) under near UV–Vis irradiation. Photolysis experiments showed ca. 65% degradation of PRO after 2 h irradiation, and a similar degradation in the presence of N.I.O. A more efficient PRO removal was obtained upon irradiation within a mixture of N.I.O. and OAA. Under the best conditions considered, complete degradation (> 95%) was observed in less than 10 min, and TOC decreased by 60% after 3 h irradiation. The observed processes were adequately fitted by pseudo-first-order kinetics, the corresponding rate constants were determined, and the effect of different variables analyzed. Photodegradation of PRO is accelerated under acidic conditions, and neutralization takes place along the reaction. Hydroxyl radicals play a predominant role in the photodegradation reaction, as shown by the dramatic inhibition observed upon t-butanol addition. Furthermore, HOradical dot formation is strongly dependent on the pH of the medium. LC-MS identification of ten different intermediates leads to the proposal of a degradation mechanism. This photocatalytic system has also proven effective, for the first time, in different real aqueous matrices (river water > distilled water > sewage ≫ > seawater, revealing quite efficient in the former) and also employing sunlight, where PRO photodegradation was slower. The results obtained show that N.I.O.-oxalate complexes are a green, cheap choice for removing organic pollutants in aqueous solution.The authors acknowledge the financial support of the Ministry of Higher Education and Scientific Research of Algeria (Project B00L01UN250120210003) and for research visits of WR and HB to UDC. This research was partially supported by the React! Group at UDC, and funded by the Spanish Ministerio de Economía y Competitividad through project CTQ2015-71238-R (MINECO/FEDER), and the Xunta de Galicia (Project GPC ED431B 2020/52), respectively. Funding for open access publication was provided by Universidade da Coruña/CISUGArgelia. Ministre de l'Enseignement Supérieur et de la Recherche Scientifique; B00L01UN250120210003Xunta de Galicia; ED431B 2020/5

Low-Molecular Weight Heparin Increases Circulating sFlt-1 Levels and Enhances Urinary Elimination

Rationale: Preeclampsia is a devastating medical complication of pregnancy which leads to maternal and fetal morbidity and mortality. While the etiology of preeclampsia is unclear, human and animal studies suggest that excessive circulating levels of soluble fms-like tyrosine-kinase-1 (sFlt-1), an alternatively spliced variant of VEGF-receptor1, contribute to the signs and symptoms of preeclampsia. Since sFlt-1 binds to heparin and heparan sulfate proteoglycans, we hypothesized that the anticoagulant heparin, which is often used in pregnancy, may interfere with the levels, distribution and elimination of sFlt-1 in vivo. Objective: We systematically determined serum and urine levels of angiogenic factors in preeclamptic women before and after administration of low molecular weight heparin and further characterized the interaction with heparin in biochemical studies. Methods and Results: Serum and urine samples were used to measure sFlt-1 levels before and after heparin administration. Serum levels of sFlt-1 increased by 25% after heparin administration in pregnant women. The magnitude of the increase in circulating sFlt-1 correlated with initial sFlt-1 serum levels. Urinary sFlt-1 levels were also elevated following heparin administration and levels of elimination were dependent on the underlying integrity of the glomerular filtration barrier. Biochemical binding studies employing cation exchange chromatography revealed that heparin bound sFlt-1 had decreased affinity to negatively charged surfaces when compared to sFlt-1 alone. Conclusion: Low molecular weight heparin administration increased circulating sFlt1 levels and enhanced renal elimination. We provide evidence that both effects may be due to heparin binding to sFlt1 and masking the positive charges on sFlt1 protein

Low-Molecular Weight Heparin Increases Circulating sFlt-1 Levels and Enhances Urinary Elimination

Rationale: Preeclampsia is a devastating medical complication of pregnancy which leads to maternal and fetal morbidity and mortality. While the etiology of preeclampsia is unclear, human and animal studies suggest that excessive circulating levels of soluble fms-like tyrosine-kinase-1 (sFlt-1), an alternatively spliced variant of VEGF-receptor1, contribute to the signs and symptoms of preeclampsia. Since sFlt-1 binds to heparin and heparan sulfate proteoglycans, we hypothesized that the anticoagulant heparin, which is often used in pregnancy, may interfere with the levels, distribution and elimination of sFlt-1 in vivo. Objective: We systematically determined serum and urine levels of angiogenic factors in preeclamptic women before and after administration of low molecular weight heparin and further characterized the interaction with heparin in biochemical studies. Methods and Results: Serum and urine samples were used to measure sFlt-1 levels before and after heparin administration. Serum levels of sFlt-1 increased by 25% after heparin administration in pregnant women. The magnitude of the increase in circulating sFlt-1 correlated with initial sFlt-1 serum levels. Urinary sFlt-1 levels were also elevated following heparin administration and levels of elimination were dependent on the underlying integrity of the glomerular filtration barrier. Biochemical binding studies employing cation exchange chromatography revealed that heparin bound sFlt-1 had decreased affinity to negatively charged surfaces when compared to sFlt-1 alone. Conclusion: Low molecular weight heparin administration increased circulating sFlt1 levels and enhanced renal elimination. We provide evidence that both effects may be due to heparin binding to sFlt1 and masking the positive charges on sFlt1 protein

Scanned Potential Microscopy of Edge and Bulk Currents in the Quantum Hall Regime

Using an atomic force microscope as a local voltmeter, we measure the Hall voltage profile in a 2D electron gas in the quantum Hall (QH) regime. We observe a linear profile in the bulk of the sample in the transition regions between QH plateaus and a distinctly nonlinear profile on the plateaus. In addition, localized voltage drops are observed at the sample edges in the transition regions. We interpret these results in terms of theories of edge and bulk currents in the QH regime.Comment: 4 pages, 5 figure

Fine sediment reduces vertical migrations of Gammarus pulex (Crustacea: Amphipoda) in response to surface water loss

Surface and subsurface sediments in river ecosystems are recognized as refuges that may promote invertebrate survival during disturbances such as floods and streambed drying. Refuge use is spatiotemporally variable, with environmental factors including substrate composition, in particular the proportion of fine sediment (FS), affecting the ability of organisms to move through interstitial spaces. We conducted a laboratory experiment to examine the effects of FS on the movement of Gammarus pulex Linnaeus (Crustacea: Amphipoda) into subsurface sediments in response to surface water loss. We hypothesized that increasing volumes of FS would impede and ultimately prevent individuals from migrating into the sediments. To test this hypothesis, the proportion of FS (1–2 mm diameter) present within an open gravel matrix (4–16 mm diameter) was varied from 10 to 20% by volume in 2.5% increments. Under control conditions (0% FS), 93% of individuals moved into subsurface sediments as the water level was reduced. The proportion of individuals moving into the subsurface decreased to 74% at 10% FS, and at 20% FS no individuals entered the sediments, supporting our hypothesis. These results demonstrate the importance of reducing FS inputs into river ecosystems and restoring FS-clogged riverbeds, to promote refuge use during increasingly common instream disturbances

Molecular Biomarkers of Vascular Dysfunction in Obstructive Sleep Apnea

Untreated and long-lasting obstructive sleep apnea (OSA) may lead to important vascular abnormalities, including endothelial cell (EC) dysfunction, hypertension, and atherosclerosis. We observed a correlation between microcirculatory reactivity and endothelium-dependent release of nitric oxide in OSA patients. Therefore, we hypothesized that OSA affects (micro)vasculature and we aimed to identify vascular gene targets of OSA that could possibly serve as reliable biomarkers of severity of the disease and possibly of vascular risk. Using quantitative RT-PCR, we evaluated gene expression in skin biopsies of OSA patients, mouse aortas from animals exposed to 4-week intermittent hypoxia (IH; rapid oscillations in oxygen desaturation and reoxygenation), and human dermal microvascular (HMVEC) and coronary artery endothelial cells (HCAEC) cultured under IH. We demonstrate a significant upregulation of endothelial nitric oxide synthase (eNOS), tumor necrosis factor-alpha-induced protein 3 (TNFAIP3; A20), hypoxia-inducible factor 1 alpha (HIF-1α?? and vascular endothelial growth factor (VEGF) expression in skin biopsies obtained from OSA patients with severe nocturnal hypoxemia (nadir saturated oxygen levels [SaO2]<75%) compared to mildly hypoxemic OSA patients (SaO2 75%–90%) and a significant upregulation of vascular cell adhesion molecule 1 (VCAM-1) expression compared to control subjects. Gene expression profile in aortas of mice exposed to IH demonstrated a significant upregulation of eNOS and VEGF. In an in vitro model of OSA, IH increased expression of A20 and decreased eNOS and HIF-1α expression in HMVEC, while increased A20, VCAM-1 and HIF-1αexpression in HCAEC, indicating that EC in culture originating from distinct vascular beds respond differently to IH stress. We conclude that gene expression profiles in skin of OSA patients may correlate with disease severity and, if validated by further studies, could possibly predict vascular risk in OSA patients

Post translational changes to α-synuclein control iron and dopamine trafficking : a concept for neuron vulnerability in Parkinson's disease

Parkinson's disease is a multifactorial neurodegenerative disorder, the aetiology of which remains elusive. The primary clinical feature of progressively impaired motor control is caused by a loss of midbrain substantia nigra dopamine neurons that have a high α-synuclein (α-syn) and iron content. α-Syn is a neuronal protein that is highly modified post-translationally and central to the Lewy body neuropathology of the disease. This review provides an overview of findings on the role post translational modifications to α-syn have in membrane binding and intracellular vesicle trafficking. Furthermore, we propose a concept in which acetylation and phosphorylation of α-syn modulate endocytic import of iron and vesicle transport of dopamine during normal physiology. Disregulated phosphorylation and oxidation of α-syn mediate iron and dopamine dependent oxidative stress through impaired cellular location and increase propensity for α-syn aggregation. The proposition highlights a connection between α-syn, iron and dopamine, three pathological components associated with disease progression in sporadic Parkinson's disease