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Water Dynamics under Drip Irrigation to Proper Manage Water Use in Arid Zone

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Journal of Agricultural Chemistry and Environment 2021年第1期10卷 57-68页

作者： Siguibnoma Kevin Landry Ouédraogo Marcel Bawindsom Kébré francois zougmoré Laboratoire de Matériaux et Environnement Université Joseph KI-ZERBO Ouagadougou Burkina Faso

The water resources reduction due to climate changes and also population increase, have contributed to increasing the constraint on water disponibility and accessibility. In the agricultural field, we need moderate soil and water resources management. This work aims to simulate water dynamics in soil under drip irrigation system in arid regions to better manage irrigation water. Simulations are done with soil physical properties of Burkina Faso. We assess maize plant water requirements for the whole growing season. With Hydrus 2D, we simulate water supply in the soil column. We assign atmospheric conditions on the top of the domain, zero flux of water on the lateral sides, and free drainage on the bottom boundary domain. We perform many irrigation events to analyze wetting pattern distribution around the emitter, which allowed us to contain the amount of irrigation water applied, only around the area dominated by roots, and then reduce water losses that roots cannot uptake. According to the different growing stages of the maize crop, we choose proper irrigation duration and frequency, and suggest irrigation schedule for the whole growing season.

关键词： Drip Irrigation Water Dynamics Hydrus (2D/3D) Water

Assessment of Heavy Metal Concentration and Evaluation of Health Risk of Some Vegetables Cultivated in Loumbila Farmland, Burkina Faso

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Journal of Environmental Protection 2021年第12期12卷 1019-1032页

作者： Tougma Kiswendsida Alain Bambara Telado Luc Doumounia Ali Derra Moumoni Inoussa Zongo francois zougmoré Laboratory of Materials and Environment Physics Department University Joseph Ki-Zerbo Ouagadougou Burkina Faso Physics and Chemical Department Institute of Sciences Ouagadougou Burkina Faso Physics Department University Norbert Zongo Koudougou Burkina Faso National Center of Scientific Research and Technology Ouagadougou Burkina Faso Physics Department University Joseph Ki-Zerbo Ouagadougou Burkina Faso

Vegetables such as spinach, African eggplant, cabbage, eggplant, okra, chili peppers and tomatoes are found in our everyday foods and are the most important dietary source of nutrient. But, it becomes deleterious to human as well as animals as it accumulates toxic metals in their tissue when grown in contaminated soil. The mostly consumed vegetables like spinach, African eggplant (fruit and leaves), Corchorus olitorius leaf, Amaranthus hybridus leaf, cabbage, eggplant, okra, pepper and tomato were collected from Loumbila market gardening. Heavy metals copper (Cu), nickel (Ni), lead (Pb), chromium (Cr), cadmium (Cd) and zinc (Zn) were measured using atomic absorption spectrophotometer (AAS) model AANALYST 200 from PERKIN ELMER. The results of this study showed that the concentrations of lead (0.49 to 8.59 mg/kg) and zinc (20.73 to 71.29 mg/kg) in spinach, African eggplant (fruit and leaves), Corchorus olitorius leaf, Amaranthus hybridus leaf, cabbage, eggplant, okra, pepper and tomato exceeded the permissible level of FAO and WHO standard. The daily plant metal intake for Cd (0.001 - 0.015 mg/kg), Pb (0.041 - 0.730 mg/kg), and Cu (0.703 - 1.543 mg/kg) is higher than the recommended daily intake of metals but does not exceed the tolerable limit. The calculated values of the health risk indices show high values for Cd, Pb, Zn, Ni and Cu while low values are observed for Cr. Except for Cr, the IRS evaluated for all the studied metals were greater than one (IRS > 1). This implies that exposed populations are susceptible to developing diseases linked to the following metals: Cd, Pb, Zn, Ni and Cu.

关键词： Heavy Metals Concentration Daily Intake Health Risk Index Vegetables

Levels of Heavy Metals in Some Vegetables and Human Health Risk Assessment in Loumbila Area, Burkina Faso

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Open Journal of Applied Sciences 2023年第9期13卷 1498-1511页

作者： Telado Luc Bambara Moumouni Derra Karim Kaboré Kiswendsida Alain Tougma Ousmane I. Cissé francois zougmoré Institute of Sciences and Technology “Ecole Normale Superieure” Koudougou Burkina Faso Physics Department University Norbert Zongo Koudougou Burkina Faso Physics Department Virtual University Ouagadougou Burkina Faso Laboratory of Materials and Environment University Joseph KI-ZERBO Ouagadougou Burkina Faso

Contamination by heavy metals of soil, water and agricultural products is currently a major problem of environmental pollution in the world. The consumption of plants contaminated with heavy metals can be the cause of diseases such as cancers, the number of cases of which is only growing. The objective of this study was to determine the concentration of copper (Cu), chromium (Cr), zinc (Zn), lead (Pb), nickel (Ni), and cadmium (Cd) in plants from the vegetable farm of LOUMBILA and the assessment of health risks linked to the consumption of plants. In this paper, the concentration of heavy metal in vegetable was measured using the model AANALYST 200 flame atomic absorption spectrometer from PERKIN ELMER. The level of Zn in the vegetables from Loumbila vegetable farms ranged between 42.95 mg/kg and 78 mg/kg. The concentrations of Zn in the studies vegetables were higher than the permissible levels set by FAO/WHO (20 mg/kg). The concentration Pb in vegetables varied from 1.73 mg/kg to 27.02 mg/kg. All concentrations of Pb in vegetable were higher than the permissible levels set by FAO/WHO (0.3 mg/kg). Daily intake of Ni, Cr and Pb was higher than the MTDI, so consumption of vegetables from Loumbila vegetable farms can lead to health problems related to Ni, Cr and Pb. In vegetables from LOUMBILA, the estimated daily intake decreased in the following order: Zn > Cu > Pb > Ni > Cr. The Hazard index values for carrot, onion, lettuce, green bean and onion leaves were greater than (>) one (1) which indicates that there might be a potential health risk to those consuming these vegetables. The Target Cancer Risk (TCR) analysis also revealed the potential cancer risk induced by Cu, Ni, Zn, Cr and Pb due to the consumption of carrot, onion leaves, onion, lettuce, green bean, and bell pepper because their TCR values were above the threshold.

关键词： Heavy Metal Concentration Vegetables Daily Intake Hazard Index

Characterisation of the granular dynamics at the interface between a pipe and a granular flow in a rotating drum

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Particuology 2024年第3期86卷 117-125页

作者： francois Rioual Paule Emmanuelle Eva Gbehe Research Unit FRISE National Research Institute for Agriculture Food and the Environment1 Rue Pierre Gilles De Gennes92160AntonyFrance

A new mobile bed heat exchanger is presented in this work which is composed of a flowing granular material in a rotating drum and a cylindrical pipe with potential interest in different energy applications as cooling,heating or heat recovery *** optimal design of the device requires a characterisation of the phenomena involved at the interface between the granular flow and the *** process is modelled by the discrete element method and a global classification of the flow patterns around the pipe is presented with respect to the three main control parameters of the problem:the Froude number,the diameter ratio and the relative filling height of the *** second part is devoted to the characterisation of the structure of the flow at the interface(velocity field,density field)in particular in a so-called Biflow regime where granular motion occurs above as well as below the pipe which is favourable to transfer by convection.A typical behavior at the interface with the pipe consists of a zone I with high velocities of particles at the top of the pipe,a second zone with quasistatic particles or low velocity particles at the front and at the bottom of the pipe and a last zone ll of depletion of particles at the back of the *** Froude number has a limited effect on the features of this structure on the first layer in the range of Froude numbers considered whereas the relative height is a more determinant parameter to control the relative magnitude of velocities in zone I and zone Il as well as the extent of the depletion *** first hydrodynamical characterisation can shed light on the dynamical regimes with improved transfer between the particles and the pipe boundary.

关键词： Granular flow Transfer Heat exchange Mobile bed Boundary condition

Incidental and secondary findings in trio exome sequencing

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Genes & Diseases 2024年第4期11卷 152-154页

作者： Camille Cohen Emeline Bellanger Jeremie Mortreux Laure Raymond francois Vialard Rodolphe Dard Department of Genetics Centre Hospitalier Intercommunal de Poissy-Saint-Germain-en-LayePoissy 78300France RHuMA UMR-BREEDINRA-ENVA-UVSQMontigny le Bretonneux 78180France Service de Genetique Laboratoire Eurofins BiomnisLyon 69007France

Exome sequencing(ES)generates secondary findings(SFs)in 2%of tested individuals if one follows the American College of Medical Genetics and Genomics(ACMG)guide-lines.i,z2 However,the rate of incidental and secondary findings(ISFs)is higher in routine clinical practice because of(i)the use of trio ES instead of solo sequencing and(i)the exclusion of the incidental findings(IFs)of medical value concerning genes in the ACMG ***,it is not clear how sufficient is a restricted list of genes to detect every ISF of major clinical value;and what is the amount of additional workload for the laboratory.

关键词： routine clinical finding

Design and Experimental Testing of a Moving Coil Actuator with Compensation Coil

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 707-716页

作者： Boyuan Yin Xianwu Zeng John Frederick Eastham Emelie Nilsson Jean-francois Rouquette Jean Rivenc Ludovic Ybanez Xiaoze Pei Department of Electronics&Electrical Engineering University of BathBathBA27AYUnited Kingdom Airbus UpNext BlangnacFrance Airbus CRT BlangnacFrance Department of Mechanical Engineering University of BathBathBA27AYUnited Kingdom

Hydrogen-powered electric aircraft have attracted significant interests aiming to achieve decarbonization *** DC electric networks are facing great challenges in DC fault protection *** interrupters are widely used in low voltage and medium voltage power systems due to being environmentally friendly with low *** this paper a moving coil actuator with compensation coils for a vacuum interrupter,as part of a hybrid direct current circuit breaker,is designed and experimentally *** coils are used to improve operating speed compared with original moving coil *** between four possible connections of compensation coils and original moving coil actuator are carried *** results show comparisons between different connections of actuator coils in terms of opening time and coil current with a range of pre-charged capacitor *** performance of each actuator connection is also *** actuator with compensation coils is shown to have a higher current rising rate and achieve faster opening speed,which is a critical requirement for electric aircraft network *** parallel connection actuator achieves the highest opening speed within 3.5 ms with capacitor voltage of 50 V.

关键词： Circuit breaker compensation coil moving coil actuator vacuum interrupter

From Control Theory to Gravitational Waves

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Advances in Pure Mathematics 2024年第2期14卷 49-100页

作者： Jean-francois Pommaret CERMICS Ecole des Ponts Paris Tech Paris France

When D:ξ→η is a linear ordinary differential (OD) or partial differential (PD) operator, a “direct problem” is to find the generating compatibility conditions (CC) in the form of an operator D1:η→ξ such that Dξ = η implies D1η = 0. When D is involutive, the procedure provides successive first-order involutive operators D1,...,Dn when the ground manifold has dimension n. Conversely, when D1 is given, a much more difficult “inverse problem” is to look for an operator D:ξ→η having the generating CC D1η = 0. If this is possible, that is when the differential module defined by D1 is “torsion-free”, that is when there does not exist any observable quantity which is a sum of derivatives of η that could be a solution of an autonomous OD or PD equation for itself, one shall say that the operator D1 is parametrized by D. The parametrization is said to be “minimum” if the differential module defined by D does not contain a free differential submodule. The systematic use of the adjoint of a differential operator provides a constructive test with five steps using double differential duality. We prove and illustrate through many explicit examples the fact that a control system is controllable if and only if it can be parametrized. Accordingly, the controllability of any OD or PD control system is a “built in” property not depending on the choice of the input and output variables among the system variables. In the OD case and when D1 is formally surjective, controllability just amounts to the formal injectivity of ad(D1), even in the variable coefficients case, a result still not acknowledged by the control community. Among other applications, the parametrization of the Cauchy stress operator in arbitrary dimension n has attracted many famous scientists (G. B. Airy in 1863 for n = 2, J. C. Maxwell in 1870, E. Beltrami in 1892 for n = 3, and A. Einstein in 1915 for n = 4).

关键词： Differential Operator Differential Sequence Killing Operator Riemann Operator Bianchi Operator Cauchy Operator Control Theory Controllability Elasticity General Relativity

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A Taste of Success

ChinAfrica 2024年第5期16卷 44-45页

作者： francois ESSOMBA Cameroon

Cooperation between China and Cameroon has reached extraordinary heights over the past two decades,which has deepened both the diplomatic and economic *** mutually beneficial partnership has made China the leading buyer of Cameroonian products,with a market share of 25.8 percent in 2021,and the leading supplier,with a market share of 17.5 percent in 2020,according to data from the National Institute of Statistics of Cameroon.

关键词： mutually market partnership

Toward a Malaria-Free Future

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Beijing Review 2024年第23期67卷 30-31页

作者： francois Essomba ChinAfrica magazine

Malaria is a potentially fatal disease transmitted by certain species of *** to the World Health Organization(WHO),globally in 2022,there were an estimated 249 million malaria cases and 608,000 malaria deaths in 85 *** was the location of 94 percent of malaria cases and 95 percent of malaria deaths,with children under 5 there accounting for about 80 percent of all malaria deaths.

关键词： Malaria malaria cases