检索结果-南通市图书馆

Health Risks Assessment in Three Urban Farms of Paris Region for Different Scenarios of Urban Agricultural Users:A Case of Soil Trace Metals Contamination

引用

Agricultural Sciences 2019年第3期10卷 352-370页

作者： Anne Barbillon Christine Aubry Francois Nold stéphane besancon Nastaran Manouchehri UMR SAD-APT INRAUniversitéParis-SaclayParisFrance Laboratory of Agronomy of the Paris City Paris Green Space and Environmental Division(DEVE)Parc Floral-Pavillon 5—Rond-Point de la PyramideParisFrance UMR Ingénierie Procédés Aliments AgroParisTechINRAUniversitéParis-SaclayMassyFrance

Within the context of a worldwide emergence of various forms of urban agriculture, there is a growing awareness concerning the health risks associated to the presence of different pollutants influencing the urban products safety. Among the most common pollutants found in soils and vegetables grown in the city, Trace Metals (TM’s) are of major concern. This paper deals with risks assessment associated with the presence of TM’s in soil, via two main exposure path ways: soil and vegetables ingestions. Risks assessments were conducted for various types of real scenarios encountered in three forms of urban farms near Paris (Ile-de-France Region). The farms have soil TM’s levels in abnormally high concentrations (Pb (Lead), Cd (Cadmium), Hg (Mercury), Cu (Copper) and Zn (Zinc) contents higher than geochemical backgrounds and threshold values for sludge spreading, often used as reference values in France). The results of the Hazard Quotient (HQ)-based risk assessment approach (HQ defined as the ratio of estimated daily intake/tolerable daily intake) show that the most risky scenarios concern urban farmers (HQtot = 1.02, because of the on-site working on a daily basis all year round), children gardeners (HQtot = 1.29) and regular children consumers (HQtot = 1.6 in maximalist scenario, where the consumer would exclusively consume the vegetables of the farm). Next would be the adult gardener scenario (HQtot= 0.9), while the least risky are adult consumer scenarios (HQtot = 0.62) and the farm workers (HQtot = 0.45). For the highest risk scenarios (urban farmers and children), specific and drastic measures may be considered, such as reducing the site frequentation by sensitive populations (child and pregnant women) or proceeding to control analysis of TM’s levels in blood for the most exposed peoples. The choice of parameters used in HQ-based method must be appropriated to the specificities of urban agricultural activities. The uncertainties in the choice of some parameters suc

关键词： Urban Agriculture Pollutants

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Use of Sequential, Single and Kinetic Extractive Schemes to Assess Cadmium (Cd) and Lead (Pb) Availability in Vietnamese Urban Soils

引用

American Journal of Analytical Chemistry 2014年第17期5卷 1214-1227页

作者： Nastaran Manouchehri Thi Minh Loi Nguyen stéphane besancon Lan Anh Le Alain Bermond AgroParistech UMR 1145 Paris France AgroParistech Laboratoire de Chimie Analytique Paris France Laboratory of Analytical Science and Technology Institute of Chemistry Hanoi Vietnam

Modified BCR sequential extraction, single equilibrium-based EDTA extraction and kinetic fractionation were used for estimating the Pb and Cd availability in a series of soil samples from 3 sites located in urban areas of Hanoi (Vietnam). These schemes were compared to identify a simple, rapid and cheap protocol for routine estimation of Pb and Cd remobilizable fraction and the related potential risk. The comparison of these three approaches revealed their convergence in terms of mobility patterns observed for Pb and Cd. Cd was characterized by higher extractibality and mobility whatever the approach. Pb was distinguished of Cd by its high association to Feoxides, lower extractability, lower rate of desorption and then lower mobility. For this environmental scenario, EDTA single scheme at equilibrium could be suggested as the best suited and a simple protocol for determination of the labile pool of Cd and Pb. The pseudo-total concentrations of Pb and Cd are actually below the Vietnamese standard level, contrary to the results obtained by other authors for agricultural soils at other urban sites of Hanoi.

关键词： Trace Metal Soil Sequential Extraction Kinetic Fractionation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Simple calculator to estimate the medical cost of diabetes in sub-Saharan Africa

引用

World Journal of Diabetes 2015年第16期6卷 1312-1322页

作者： Koffi Alouki Hélène Delisle stéphane besancon Naby Baldé Assa Sidibé-Traoré Joseph Drabo Francois Djrolo Jean-Claude Mbanya Serge Halimi Department of Nutrition Faculty of MedicineUniversity of MontrealDowntown Station Santé-Diabète (NGO) Mali Chapter Endocrinology Department Donka Teaching Hospital Internal Medicine Department Bamako University Hospital Internal Medicine Department Ouagadougou University Hospital Endocrinology Department National University Health Centre Department of Internal Medicine and Specialties Faculty of Medicine and Biomedical SciencesUniversity of Yaoundé I University Joseph Fourier and University Hospital Centre

AIM: To design a medical cost calculator and show that diabetes care is beyond reach of the majority particularlypatients with ***: Out-of-pocket expenditures of patients for medical treatment of type-2 diabetes were estimated based on price data collected in Benin,Burkina Faso,Guinea and Mali. A detailed protocol for realistic medical care of diabetes and its complications in the African context was defined. Care components were based on existing guidelines,published data and clinical experience. Prices were obtained in public and private health facilities. The cost calculator used Excel. The cost for basic management of uncomplicated diabetes was calculated per person and per year. Incremental costs were also computed per annum for chronic complications and per episode for acute complications. RESULTS: Wide variations of estimated care costs were observed among countries and between the public and private healthcare system. The minimum estimated cost for the treatment of uncomplicated diabetes(in the public sector) would amount to 21%-34% of the country's gross national income per capita,26%-47% in the presence of retinopathy,and above 70% for nephropathy,the most expensive complication. CONCLUSION: The study provided objective evidence for the exorbitant medical cost of diabetes considering that no medical insurance is available in the study countries. Although the calculator only estimates the cost of inaction,it is innovative and of interest for several stakeholders.

关键词： Diabetes Non-communicable diseases Africa Advocacy Cost-of-illness

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

statistical physics in QCD evolution towards high energies

引用

Science China(Physics,Mechanics & Astronomy) 2015年第8期58卷 1-32页

作者： MUNIER stphane Centre de physique thorique ′Ecole PolytechniqueCNRS Palaiseau France

The concepts and methods used for the study of disordered systems have proven useful in the analysis of the evolution equations of quantum chromodynamics in the high-energy regime: Indeed, parton branching in the semi-classical approximation relevant at high energies and at a fixed impact parameter is a peculiar branching-diffusion process, and parton branching supplemented by saturation effects(such as gluon recombination) is a reaction-diffusion process. In this review article, we first introduce the basic concepts in the context of simple toy models, we study the properties of the latter, and show how the results obtained for the simple models may be taken over to quantum chromodynamics.

关键词： quantum chromodynamics color dipole model color glass condensate stochastic fronts traveling waves reaction-diffusion

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Comparative study of abrasion via microindentation and microscratch tests of reinforced and unreinforced lamellar cast iron

引用

Friction 2019年第5期7卷 457-465页

作者： Mohammed MENDAS stéphane BENAYOUN Laboratory of Rheology and Mechanics(LRM) Hassiba Benbouali University of ChlefHay Essalem Chlef BP151(02000)Algeria LTDS UMR CNRS5513Ecole Centrale de LyonUniversity of LyonEcully Cedex F-69134France

This study compares micro-abrasive wear in two kinds of grey cast iron. Classical lamellar cast iron with fully pearlitic matrix(FGL1) and lamellar micro-alloyed cast iron with phosphorus and boron(FGL2) are used. FGL2 has a fully pearlitic matrix reinforced by the hard phosphorus eutectic phase. The microstructures of these two types of iron are mechanically characterized using nanoindentation tests. Vickers microindentation and microscratch tests are also performed on these iron samples. The indent and scratch images obtained via scanning electron microscopy were used to compare the scratch damage to the two kinds of iron. The friction coefficient is discussed in terms of applied load, indenter attack angle, and scratch damage. Nanoindentation tests show an improvement in graphite’s mechanical properties and an increase in the matrix hardness of the FGL2, relatively to FGL1. The same damage forms for both microindentation and microscratch testing were observed for the two iron samples. However, cracking of the hard phase is observed in FGL2. The results show that the scratching of the micro-alloyed iron(FGL2) leads to less matrix damage and to an extended microploughing wear mechanism. However, at low normal load, the reinforcement of the matrix can increase the friction coefficient.

关键词： grey cast iron indentation microscratch abrasive wear

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Solar chemical looping reforming of methane combined with isothermal H2O/CO2 splitting using ceria oxygen carrier for syngas production

引用

Journal of Energy Chemistry 2020年第2期29卷 60-72页

作者： Srirat Chuayboon stéphane Abanades Sylvain Rodat Processes Materials and Solar Energy LaboratoryPROMES-CNRSFont-Romeu 66120France Department of Mechanical Engineering King Mongkut's Institute of Technology LadkrabangPrince of Chumphon CampusChumphon 86160Thailand Universite Grenoble Alpes Le-Bourget-du-Lac F-73375France CEA-LJTEN Laboratoire des Systemes Solaires Haute Temperature(LSHT) Grenoble F-38054France

The chemical looping reforming of methane through the nonstoichiometric ceria redox cycle(CeO2/CeO2-δ) has been experimentally investigated in a directly irradiated solar reactor to convert both solar energy and methane to syngas in the temperature range 900–1050 °C. Experiments were carried out with different ceria shapes via two-step redox cycling composed of endothermic partial reduction of ceria with methane and complete exothermic re-oxidation of reduced ceria with H2 O/CO2 at the same operating temperature, thereby demonstrating the capability to operate the cycle isothermally. A parametric study considering different ceria macrostructure variants(ceria packed powder, ceria packed powder mixed with inert Al2 O3 particles, and ceria reticulated porous foam) and operating parameters(methane flow-rate, reduction temperature, or sintering temperature) was conducted in order to unravel their impact on the bed-averaged oxygen non-stoichiometry(δ), syngas yield, methane conversion, and solar reactor performance. The ceria cycling stability was also experimentally investigated to demonstrate repeatable syngas production by alternating the flow between CH4 and H2 O(or CO2). A decrease in sintering temperature of the ceria foam was beneficial for increasing syngas selectivity, methane conversion,and reactor performance. Increasing both CH4 concentration and reduction temperature enhanced δ with the maximum value up to 0.41 but concomitantly favored CH4 cracking reaction. The ceria reticulated porous foam showed better performance in terms of effective heat transfer, due to volumetric absorption of concentrated solar radiation and uniform heating with lower solar power consumption, thereby promoting the solar-to-fuel energy conversion efficiency that reached up to 5.60%. The energy upgrade factor achieved during cycle was up to 1.19. stable patterns in the δ and syngas yield for consecutive cycles with the ceria foam validated material performance stability.

关键词： Chemical looping Methane reforming Ceria structure Concentrated solar power Syngas production H2O/CO2 splitting

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Conversion of the refractory ammonia and acetic acid in catalytic wet air oxidation of animal byproducts

引用

Journal of Environmental Sciences 2011年第3期23卷 520-528页

作者： Virginie Fontanier Sofiane Zalouk stéphane Barbati Aix-Marseille Universite's-CNRS (UMR 6264)-Laboratoire de Chimie Provence:quipe Chimie de l'Environnement Continental-3 Place Victor Hugo (case 29)-13331 Marseille cedex 3France

Wet air oxidation （WAO） and catalytic wet air oxidation （CWAO） of slaughtered animal byproducts （ABPs） were investigated. Two step experiment was carried out consisting of a non-catalysed WAO run followed by a CWAO run at 170-275 ℃, 20 MPa, and reaction time 180 min. The WAO （lst step） of sample （5 g/L total organic carbon （TOC）） yielded （82.0 ±4）% TOC removal and （78.4 ± 13.2）% conversion of the initial organic-N into NH4＋-N. Four metal catalysts （Pd, Pt, Rh, Ru） supported over alumina have been tested in catalytic WAO （2nd step） at elevated pH to enhance ammonia conversion and organic matter removal, particularly acetic acid. It was found that the catalysts Ru, Pt, and Rh had significant effects on the TOC removal （95.1%, 99.5% and 96.7%, respectively） and on the abatement of ammonia （93.4%, 96.7% and 96.3%, respectively） with high nitrogen selectivity. The catalyst Pd was found to have the less activity while Pt had the best performance. The X-Ray diffraction analysis showed that the support of catalyst was not stable under the experimental conditions since it reacted with phosphate present in solution. Nitrite and nitrate ions were monitored during the oxidation reaction and it was concluded that CWAO of ammonia in real waste treatment framework was in good agreement with the results obtained from the literature for ideal solutions of ammonia.

关键词： wet oxidation, heterogeneous catalysis animal byproducts acetic acid ammonia, nitrite nitrate

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

New perspectives for investigating respiratory failure induced by cervical spinal cord injury

引用

Neural Regeneration Research 2014年第22期9卷 1949-1951页

作者： Marcel Bonay stéphane Vinit Université de Versailles Saint-Quentin-en-Yvelines Unité End:icapUFR des Sciences de la Santé–Simone Veil78180 Montigny-le-BretonneuxFrance Service de Physiologie-Explorations Fonctionnelles H?pital Ambroise Paré Assistance Publique-H?pitaux de Paris(AP-HP)Groupe Hospitalier Paris Ile-de-France Ouest92104 BoulogneBillancourtFrance

Traumatic cervical spinal cord injury （SCI）, with an annual incidence of 12,000 new cases in USA （NSCISC 2013）, causes devastating locomotor and respiratory paralysis and unfortunately compromises the human patient＇s lifespan. The severity of the injury depends on the degree and the extent of the initial trauma. In fact, respiratory failure is the leading cause of mortality following upper cervical SCI. However, 80% of the injuries are incomplete, allowing some modest spontaneous recovery. To date, no effective treatment is available in order to restore the loss of function.

关键词： SCI New perspectives for investigating respiratory failure induced by cervical spinal cord injury CPP

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Late-entry commercial thinning effects on Pinus banksiana:growth, yield, and stand dynamics in Québec, Canada

引用

Journal of Forestry Research 2019年第1期30卷 95-106页

作者： Martin-Michel Gauthier stéphane Tremblay Ministère des Forêts de la Faune et des Parcs du Québec Natural Resources Canada Canadian Forest Service

We studied late-entry commercial thinning effects on growth, yield, and regeneration in a 48-year-old jack pine(Pinus banksiana Lamb.) stand. Applied thinning intensities were 27, 32, and 47% of merchantable basal area(BA) excluding skidding trails. After 15 years, mean diameter at breast height of surviving trees in the 47% BA removal increased by 4.9 cm(25%) compared to the unthinned control. The 47% BA removal also increased gross merchantable volume(GMV) tree-1by 46% compared to the control. The 27% BA removal had twice as much GMV ha-1compared to the 47% BA removal after15 years. Moreover, cumulative GMV ha-1was much higher in the 27% BA removal than in the unthinned control. The highest thinning intensity produced larger trees on average, while the lowest thinning intensity maximized volume production per hectare. Maintenance of acceptable growing stock throughout the 15-year period in the 27% BA removal could provide other ecosystem functions such as biodiversity enhancement or wildlife habitat by delaying senescence. Regeneration data showed that a shift in species composition occurred in the understory. After 15 years, the understory was dominated by black spruce(Picea mariana(Mill.) B.S.P.), white birch(Betula papyrifera Marsh.), and trembling aspen(Populus tremuloides Michx.). If regenerating jack pine is an objective after final overstory removal, additional efforts will be needed to re-establish this species.

关键词： Jack pine Commercial thinning stand yield Succession Delayed senescence Tree regeneration

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Magnesium sulfate and fetal neuroprotection: overview of clinical evidence

引用

Neural Regeneration Research 2018年第12期13卷 2044-2049页

作者： Clément Chollat stéphane Marret Institut National de la Santé et de la Recherche Médicale U1245 Genetics and Pathophysiology of Neurodevelopmental Disorders Team 4Neovasc Institute of Research and Innovation in Biomedicine Rouen School of Medicine Normandy University Department of Neonatal Intensive Care Port Royal University Hospital Department of Neonatal Pediatrics and Intensive Care and Neuropediatrics Charles-Nicolle University Hospital

Antenatal administration of magnesium sulfate is an important part of the neuroprotective strategy for preterm infants. strong evidence from five randomized controlled trials and five meta-analyses has demonstrated that magnesium sulfate, when administered before preterm delivery, significantly reduces the risk of cerebral palsy at two years. Through secondary analyses of randomized controlled trials and other original clinical studies, this state-of-the-art review highlights the absence of serious adverse effects in both pregnant women and neonates, as well as the impact of maternal body mass index and preeclamptic status on the maternal and neonatal magnesium levels, which could influence the magnitude of the neuroprotective effect. Although antenatal magnesium sulfate is a cost-effective strategy, some practice surveys have demonstrated that the use of magnesium sulfate is not sufficient and that its use is heterogeneous, differing among different maternity wards. Since 2010, an increasing number of obstetrical societies have recommended its use to improve the neurological outcomes of preterm infants, especially the International Federation of Gynecology and Obstetrics and World Health Organization in 2015, and France in 2017. Considering the neuroprotective impact of magnesium sulfate when administered before delivery, postnatal administration should be considered, and its effects should be assessed using randomized controlled trials.

关键词： magnesium sulfate preterm birth neuroprotection cerebral palsy neurodevelopment international recommendations clinical studies meta-analysis preeclampsia cost-effectiveness

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：