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Assessment of the Moroccan Mediterranean Coasts Contamination by Hydrocarbons (Non Aromatic Hydrocarbons, Aromatic Hydrocarbons and Linear Alkylbenzenes)

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International Journal of Geosciences 2011年第4期2卷 562-572页

作者： Saida Bouzid Soumaya Khannous Ioanna Bouloubassi alain Saliot Hassan er Raioui 不详

In order to evaluate the contamination of the Moroccan Mediterranean coasts by persistent organic pollutants we studied hydrocarbons and linear alkylbenzenes in bivalve tissues (cockles) collected seasonally from several points along the western Moroccan coasts in the Mediterranean Sea. Two fractions corresponding to non aromatic and aromatic hydrocarbons were analyzed by GC/FID and GC/MS. Non aromatic hydrocarbon concentrations vary in the range of 24.1 - 2731 μg/g dry weight (dw) while total n-alkanes vary from 2.2 to 68.2 μg/g. Few exceptions were noted with values up to 243 μg/g (dw), which is high compared to other Mediterranean sites. The presence of an important unresolved complex mixture (UCM) indicated a significant petroleum contamination, confirmed by the identification of 17α(H), 21β(H) hopanes. Biogenic contributions were also detected within the n-alkane distribution (n-C17, n-C18, n-C27, n-C29, n-C17, /Pr, n-C18, /Ph) and by the presence of alkenes. C13, and C14, linear alkylbenzenes were found at concentrations of 478 - 1954 ng/g. and point to pollutant inputs from wastewaters. Polycyclic aromatic hydrocarbons were present in low concentrations below the GC detection limit. The observed seasonal and spatial variations were linked to the magnitude of inputs from marine and land-based pollutant discharges.

关键词： Western Moroccan Mediterranean Coast Bivalves Contamination Gas Chromatography Hydrocarbons Biogeochemical Markers Petrogenic and Biogenic Origins

Topology-enhanced mechanical stability of swelling nanoporous electrodes

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npj Computational Materials 2023年第1期9卷 1161-1175页

作者： Benjamin E.Grossman-Ponemon Ataollah Mesgarnejad alain Karma Center for Interdisciplinary Research on Complex Systems Department of PhysicsNortheastern UniversityBostonMA 02115USA School of Engineering Brown UniversityProvidenceRI 02912USA

Materials like silicon and germanium offer a 10-fold improvement in charge capacity over conventional graphite anodes in lithium-ion batteries but experience a roughly threefold volume increase during lithiation,which challenges ensuring battery *** silicon,created by liquid-metal-dealloying,is a potentially attractive anode design to mitigate this challenge,exhibiting both higher capacity and extended cycle ***,how nanoporous structures accommodate the large volume change is ***,we address this question by using phase-field modeling to produce nanoporous particles and to investigate their elastoplastic swelling behavior and *** simulations show that enhanced mechanical stability results from the network topology consisting of ligaments connected by bulbous,sphere-like *** ligaments forcefully resist elongation while the nodes,behaving like isolated spherical particles,experience large stresses driving ***,being smaller compared to a sphere of the same volume as the entire nanoporous particle,the nodes are more protected against fracture.

关键词： swelling stability attractive

nitiation of er Body Formation and Indole Glucosinolate Metabolism by the Plastidia Retrograde Signaling Metabolite, MEcPP

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Molecular Plant 2017年第11期10卷 1400-1416页

作者： Jin-Zheng Wang Baohua Li Yanmei Xiao Yu Ni Haiyan Ke Panyu Yang Amancio de Souza Marta Bjornson Xiang He Zhouxin Shen Gerd Ulrich Balcke Steve P. Briggs alain Tissier Daniel J. Kliebenstein Katayoon Dehesh Institute for Integrative Genome Biology and Department of Botany and Plant Sciences University of California Riverside CA 92521 USA Department of Plant Biology University of California Davis CA 95616 USA Department of Plant Sciences University of California Davis CA 95616 USA Division of Biological Sciences University of California San Diego La Jolla CA 92093 USA Department of Cell and Metabolic Biology Leibniz-lnstitute of Plant Biochemistry Halle Germany Present address: College of Agronomy and Biotechnology Southwest University Chongqing P.R. China Present address: Rice Research Institute Sichuan Agricultural University Changdu Sichuan 611130 China

Plants have evolved tightly regulated signaling networks to respond and adapt to environmental perturbations, but the nature of the signaling hub（s） involved have remained an enigma. We have previously established that methylerythritol cyclodiphosphate （MEcPP）, a precursor of plastidial isoprenoids and a stress- specific retrograde signaling metabolite, enables cellular readjustments for high-order adaptive functions. Here, we specifically show that MEcPP promotes two Brassicaceae-specific traits, namely endoplasmic reticulum （er） body formation and induction of indole glucosinolate （IGs） metabolism selectively, via tran- scriptional regulation of key regulators NAIl for er body formation and MYB51/122 for IGs biosynthesis）. The specificity of MEcPP is further confirmed by the lack of induction of wound-inducible er body genes as well as IGs by other altered methylerythritol phosphate pathway enzymes. Genetic analyses revealed MEcPP-mediated COil-dependent induction of these traits. Moreover, MEcPP signaling integrates the biosynthesis and hydrolysis of IGs through induction of nitrile-specifier protein1 and reduction of the sup- pressor, ESM1, and production of simple nitriles as the bioactive end product. The findings position the plastidial metabolite, MEcPP, as the initiation hub, transducing signals to adjust the activity of hard- wired gene circuitry to expand phytochemical diversity and alter the associated subcellular structure required for functionality of the secondary metabolites, thereby tailoring plant stress responses.

关键词： glucosinolates er body retrograde signaling MEP pathway MEcPP stress

Prevention of Mother-to-Child Transmission of Hepatitis B in the Urban District Health Baskuy Burkina Faso

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Open Journal of Gastroenterology 2016年第6期6卷 175-187页

作者： Alice Nanelin Guingané Nicolas Meda Roger Sombié Christiane Béré/Somé Lydie Sia Rose Ido/Da Issa Guiraud alain Bougouma Service d’Hépatogastroentérologie CHU-Yalgado Ouédraogo Ouagadougou Burkina Faso Aix Marseille University IRD UMR-S912 Marseille France Faculty of Health Sciences (UFR-SDS) University of Ouaga I Pr Joseph Ki-Zerbo Ouagadougou Burkina Faso Centre MURAZ Bobo-Dioulasso Burkina Faso Institute of Research on Health Sciences Ouagadougou Burkina Faso

Few studies have been conducted on the epidemiology in pregnancy in sub-Saharan Africa. This study aimed to improve the care of pregnant women infected with hepatitis B virus (VHB) and their newborns in the urban district health. Method: This study was conducted from 01/09/2014 to 01/09/2015. Study involved three types of data collection: a collection of data from health facilities involved in the project;repeated cross-sectional survey among health personnel;a pros- pective study of pregnant women identified positive for HBsAg and followed at the University Hospital Yalgado Ouédraogo (CHU-YO). Knowledge assessment was made among health staff and pregnant women using a knowledge score. Construction of the score came after a factorial analysis of multiple correspondences on population health workers surveyed in the first round (N = 119) on one hand and all pregnant women (N = 266) on the other hand. This had identified among the 79/19 questions, those that discriminated best knowledge of paramedics and pregnant women. For pregnant women, this score was then dichotomized from the center and logistic regression was performed to determine the sociodemographic, medical and obstetric characteristics that influenced it (p value eral, the level of knowledge was good on targeted knowledge, both before and after training. No health worker routinely offered screening for hepatitis B among pregnant women attending antenatal clinics. Altogether 266 pregnant women HBsAg-positive were referred and followed CHU-YO. Half of the patients had a score lower than 2/17. Univariate analysis showed that variables such as education level influenced significantly the level of knowledge. Women with higher levels of education had a higher level of knowledge about the disease, compared to those of primary level [OR = 1.63;[1.34 to 1.99], p value eriod numbered 128 and the vaccine was

关键词： Hepatitis B Paramedics Knowledge Practices Pregnant Women Immunization Newborn

Virological profile of hepatitis B infection in Black African HBsAg chronic carriers

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Open Journal of Gastroenterology 2013年第2期3卷 113-118页

作者： Koffi alain Attia Stanislas Doffou Ya Henriette Kissi Demba Bangoura Seka Mondesir Pianiza Kouame Alassan Mahassadi Fulgence Yao Bathaix Mohamed Sayegh Thérèse N’dri-Yoman Clinique Médicale Danga Cocody Abidjan Cote d’Ivoire Service de Médecine et d’Hépato-Gastroentérologie CHU Yopougon Abidjan Cote d’Ivoire

Aims: 1) Describe virological profile of patients followed-up for chronic Hepatitis B virus (HBV);2) Search for a correlation between cirrhosis and virological profile of patients. Patients and Methods: Retrospective study about 75 HBsAg positive patients followed-up for at least one year in two medical structures of Abidjan. Studied parameters: clinical signs, biological check-up (serum transaminases every 3 months for at least one year, platelets count and prothrombin rate), abdominal echography, virological check-up (HBsAg, HBeAg, anti-HBe, total anti-HBc, anti-VHC and anti- HIV Ab, HBV DNA biannual quantification during at least one year). Histological or biochemical evaluation of hepatic activity and fibrosis were realized in case of transaminases elevation or HBV DNA > 2000 IU/ml. Results: The mean age of our 75 patients (54 men) was 42.1 ± 11.54 years. HBV was fortuitously discovered in most of our patients (74.7% of the cases). The HBV inactive chronic carriage was 50.7%;HBeAg-positive and HBeAg-negative chronic hepatitis represented respectively 9.3% and 40% of the cases. Mean B viral load was 327.5 IU/ml in HBV inactive chronic carriers, 44,047,663 IU/ml in HBeAg-positive chronic HBV and 20,231,822 IU/ml in HBeAg-negative chronic HBV. Cirrhosis prevalence was significantly high- er in positive or negative HBeAg chronic HBV than in HBV inactive chronic carriers (32.4% vs. 5.3%, p = 0.008;OR = 8.6). Conclusion: Our patients’ virological profile was dominated by HBeAg-negative chronic HBV and HBV inactive chronic carriage. The risk of having cirrhosis was multiplied by 8.6 in case of active chronic hepatitis compared with HBV inactive chronic carriage.

关键词： Hepatitis B Virus Virological Profile Cirrhosis