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Evolution of Mother-to-Child HIv-1 Transmission Rate in Mali from 2009 to 2018

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Advances in Microbiology 2024年第5期14卷 256-267页

作者： Alou Sanogo Mohamed Ag Baraïka Maïga Aminata Demba Koita Mahamadou Abdou Mamadou Guindo Clémentine N’Diaye Fatoumata Namoudou Traoré Abdoulaye Bagayoko Youssouf Diallo Flabou Bougoudogo Ibrehima Guindo National Institute for Public Health Bamako Mali Faculty of Pharmacy (FAPH) University of Science of Technical and Technology de Bamako Bamako Mali University Hospital Center (CHU)-Point G Bamako Mali Faculty of Medecine and Odonto-Stomatology University of Science of Technical and Technology de Bamako Bamako Mali Sector Unit for the Fight against AIDS Tuberculosis and Hepatitis Bamako Mali UNICEF (United Nations Children’ s Fund) Bamako Mali

Despite enormous efforts to achieve the goal of eliminating mother-to-child transmission of HIv-1, it remains a major challenge for many countries in sub-Saharan Africa, particularly Mali. Our objective is to assess changes in the rate of mother-to-child transmission of HIv-1. We conducted a cross-sectional study between January 1, 2009 to December 31, 2018 (10 years) of early diagnosis activity in newborns and children born to HIv-1-positive mothers at the National Institute for Public Health (INSP). The samples came from health and referral centers in mali. All samples were received at the Laboratory of Molecular Biology at the INSP. Proviral DNA extraction was performed from a blood spot sample with a Roche DNA kit, Cobas AmpliPrep/Cobas TaqMan HIv-1 qualitative Test, v2.0 (Roche Molecular System, Inc, USA) following the company procedures. Molecular diagnosis was performed using the same kits using an algorithm of three identical PCRs. The Epi Info version 7 software was used for data analysis with a significance threshold of 5%. A total of 10,714 samples of infants and children born to HIv-positive mothers were analyzed by PCR. Ninety-six percent of mothers were on ARv prophylaxis (AZT 3TC NvP and AZT NvP) and 60% of newborns received the same ARv prophylaxis. Of these children, 956 tested positive with an overall transmission rate of 8.92%, varying between 7.27% in 2009 and 08.01% in 2018. This rate was relatively low among children receiving prophylaxis at 2.04% and remained high for children who received breastfeeding at 5.62%. However, the transmission rate remains low for those who have benefited from mixed and artificial breastfeeding at 1.58% and 1.27% respectively. A significant proportion of children remained infected by their mothers during pregnancy, childbirth or breastfeeding. This study shows the importance of early diagnosis of HIv in children using molecular technology.

关键词： Early Diagnosis Mothers-to-Child Newborns PCR DNA HIv-1

First-Principles Study of Electronic Structure and Optical Properties of Cubic Perovskite CsCaF_(3)

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Chinese Physics Letters 2012年第11期29卷 173-177页

作者： K.Ephraim Babu A.veeraiah D.Tirupati swamy v.veeraiah Modelling and Simulation in Materials Science Laboratory Department of PhysicsAndhra UniversityVisakhapatnamAndhra Pradesh530003India

Electronic,structural and optical properties of the cubic perovskite CsCaF_(3) are calculated by using the full potential linearized augmented plane wave(FP-LAPW)plus local orbitals method with generalized gradient approximation(GGA)in the framework of the density functional *** calculated lattice constant is in good agreement with the experimental *** electronic band structure shows that the fundamental band gap is wide and indirect at(Γ–R)*** contribution of the different bands is analyzed from the total and partial density of states *** charge density plots show strong ionic bonding in Cs-F,and ionic and weak covalent bonding between Ca and *** of the optical spectra,viz.,the dielectric function,optical reflectivity,absorption coefficient,real part of optical conductivity,refractive index,extinction coefficient and electron energy loss,are performed for the energy range 0–30 ev.

关键词： theory bonding ionic

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华南至东南亚沿海全新世环境演变与史前农业

科学通报 2024年第18期69卷 2553-2567页

作者：郑卓马婷汤永杰 Barry v.Rolett 宗永强黄康有万秋池陈聪张潇陈碧珊张绍轩中山大学地球科学与工程学院珠海519080 南方海洋科学与工程广东省实验室珠海519080 北京师范大学地表过程与资源生态国家重点实验室珠海基地珠海519087 Department of Anthropology University of Hawai'i at ManoaHawaii 96822USA 香港大学地球科学系中国香港999077 岭南师范学院地理科学学院湛江524048

华南至东南亚沿海地区新石器时期稻作农业的出现并成为主要经济形态显著滞后于长江下游.然而,对于制约华南沿海早期农业扩张的原因存在争议,而且一直以来缺少将考古证据与海岸带沉积与地貌演变的自然过程进行对比.本研究利用全新世孢粉... 详细信息

华南至东南亚沿海地区新石器时期稻作农业的出现并成为主要经济形态显著滞后于长江下游.然而,对于制约华南沿海早期农业扩张的原因存在争议,而且一直以来缺少将考古证据与海岸带沉积与地貌演变的自然过程进行对比.本研究利用全新世孢粉记录集成,结合沿海地区钻孔古环境数据集,探讨了华南至东南亚地区沿海平原的全新世沉积过程与时空演变特征,并对沉积孢粉记录进行了集成.研究区的时空对比表明,以丘陵海岸为主的华南沿海地区在中全新世因海平面上升和海侵作用,海岸线深入陆地丘陵边缘.从6~5 ka BP之后,沉积体系开始从海相为主过渡到陆相的沉积环境,但该时期的海岸带平原土地仍较狭窄,有限的可耕种土地限制了稻作农业的发展空间.虽然在一些南方的考古遗址中发现了5~4 ka BP的水稻相关遗存,但总体揭示的经济形态仍停留在采集、渔猎为主的范畴.三角洲的演变从4 ka BP开始,进入陆地扩张和湿地面积显著增加的阶段,大部分河口湿地和沿海陆地平原逐渐形成一定的规模.尤其在2.5 ka BP之后,三角洲进积作用使平原面积加速扩大,其快速变化与花粉记录指示的稻作农业发展阶段呈现高度的耦合.特别是秦汉前后大规模的农业人口南迁,新的移民带来了先进的集约化水稻种植农业技术,进一步促进了该地区水稻农业的快速发展,并加大了刀耕火种对森林的破坏和引发严重的水土流失.此外,从沿海平原到丘陵山地的早期农业发展也存在滞后现象.本研究揭示了华南和东南亚沿海地区海岸带平原的形成阶段与农业发展过程是基本同步的,印证了人类文明发展与自然环境变化相互制约与依存的人-地关系.

关键词：全新世新石器时代孢粉分析海岸线演变史前农业华南-东南亚

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Sulfamic acid as a green,reusable catalyst for stepwise,tandem&one-pot solvent-free synthesis of pyrazole derivatives

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Chinese Chemical Letters 2017年第7期28卷 1571-1576页

作者： veera swamy Konkala Pramod Kumar Dubey Department of Chemistry Jawaharlal Nehru Technological University HyderabadCollege of EngineeringKukatpally 500085India

Sulfamic acid（SA） is a bi-functional, cost-effective and reusable green catalyst for the synthesis of 4-（pyrazol-4-yl）methylenepyrazol-5（4H）-one derivatives by one-pot, three-component condensation of pyrazol-4-carbaxaldehydes, b-ketoesters and phenyl hydrazine（Route-I）. In addition to this method,another simple condensation of pyrazol-4-carbaxaldehydes with pyrazolone in the presence of SA under the solvent-free condition in good yield is reported. The merits of these protocols are mild conditions,non-aqueous workup, high yields, easy availability of the catalyst, no chromatographic separation and inexpensive solid acid catalyst. Furthermore, SA could be recycled and reused for five times without losing its catalytic activity.

关键词： Pyrazol-4-carbaxaldehydes Knoevenagel condensation Sulfamic acid Multicomponent reaction Physical grinding

Regional trauma system development in Shenzhen,China:an 8-year journey

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Military Medical Research 2022年第3期9卷 385-386页

作者： Gui-Xi Zhang Gilberto ka Kit Leung Chung Mau Lo Richard Kwong-Yin Lo John Wong Ronald v. Maier Eileen M.Bulger Joe King Man Fan Xiao-Bing Fu Chinese PLA Medical School Beijing100853China University of Hong Kong-Shenzhen Hospital Shenzhen518000China Faculty of Medicine University of Hong Kong Li Ka ShingHong Kong999077China Harborview Medical Center SeattleWA98195USA Medical Innovation Research Department and 4th Medical Center Chinese PLA General Hospital and Chinese PLA Medical SchoolBeijing100853China

Dear Editor,Since the late 1980s, trauma in China has been identified as a major public health challenge, with trafic-related fatalities accounting for 80% of accidental deaths[1]. In 2019, Shenzhen had a total population of approximately 20 million, and from 2010 to 2017, both emergency medical services and the total number of trauma patients increased, with trauma accounting for 47.0% and 38.4% of all patients in 2010 and 2017, respectively[2,3]. This report describes the efforts to implement programs and establish a trauma system in Shenzhen, China.

关键词： system services accounting

Real-world performance analysis of a novel computational method in the precision oncology of pediatric tumors

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World Journal of Pediatrics 2023年第10期19卷 992-1008页

作者： Barbara vodicska Júlia Déri Dóra Tihanyi Edit várkondi EnikőKispéter Róbert Dóczi Dóra Lakatos Anna Dirner Mátyás vidermann Péter Filotás Réka Szalkai-Dénes István Szegedi katalin Bartyik Krisztina Míta Gábor Réka Simon Péter Hauser György Péter Csongor Kiss Miklós Garami István Peták Oncompass Medicine Hungary Kft Retek Str.34Budapest 1024Hungary Division of Pediatric Hematology-Oncology Department of PediatricsFaculty of MedicineUniversity of DebrecenDebrecenHungary Department of Pediatrics Albert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary Onco-Hematology Department Velkey LászlóPaediatric Health CentreMiskolcHungary Department of Paediatrics Semmelweis UniversityBudapestHungary Onco-Hematology Department Heim Pál Children’s HospitalBudapestHungary Department of Pharmacology and Pharmacotherapy Semmelweis UniversityBudapestHungary Department of Pharmaceutical Sciences University of Illinois at ChicagoChicagoUSA Genomate Health CambridgeMAUSA

Background The utility of routine extensive molecular profiling of pediatric tumors is a matter of debate due to the high number of genetic alterations of unknown significance or low evidence and the lack of standardized and personalized decision support *** drug assignment(Dda)is a novel computational method to prioritize treatment options by aggregating numerous evidence-based associations between multiple drivers,targets,and targeted *** has been validated to improve personalized treatment decisions based on the outcome data of adult patients treated in the SHIvA01 clinical *** aim of this study was to evaluate the utility of Dda in pediatric *** Between 2017 and 2020,103 high-risk pediatric cancer patients(volved in our precision oncology program,and samples from 100 patients were eligible for further *** or blood samples were analyzed by whole-exome(WES)or targeted panel sequencing and other molecular diagnostic modalities and processed by a software system using the Dda algorithm for therapeutic decision ***,a molecular tumor board(MTB)evaluated the results to provide therapy *** Of the 100 cases with comprehensive molecular diagnostic data,88 yielded WES and 12 panel sequencing *** identified matching off-label targeted treatment options(actionability)in 72/100 cases(72%),while 57/100(57%)showed potential drug *** reached 88%(29/33)by 2020 due to the continuous updates of the evidence *** approved the clinical use of a Dda-top-listed treatment in 56 of 72 actionable cases(78%).The approved therapies had significantly higher aggregated evidence levels(AELs)than dismissed *** of WES results for targeted panels missed important mutations affecting therapy *** Dda is a promising approach to overcome challenges associated with the interpretation of extensive molecular profiling in the routine car

关键词： Computational decision support Pediatric tumors Precision oncology Tumor board

A validated stability-indicating LC method for the separation of enantiomer and potential impurities of Linezolid using polar organic mode

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Journal of Pharmaceutical Analysis 2012年第4期2卷 272-278页

作者： T.Satyanarayana Raju O.vishweshwari Kutty v.Ganesh P.Yadagiri swamy Dr.Reddy's Laboratories Ltd.Active Pharmaceutical Ingredients IPDOBachupallyHyderabad 500072A.PIndia Department of Chemistry University College of EngineeringOsmania University

Although a number of methods are available for evaluating Linezolid and its possible impurities, a common method for separation if its potential impurities, degradants and enantiomer in a single method with good efficiency remain unavailable. With the objective of developing an advanced method with shorter runtimes, a simple, precise, accurate stability-indicating LC method was developed for the determination of purity of Linezolid drug substance and drug products in bulk samples and pharmaceutical dosage forms in the presence of its impurities and degradation products. This method is capable of separating all the related substances of Linezolid along with the chiral impurity. This method can also be used for the estimation of assay of Linezolid in drug substance as well as in drug product. The method was developed using Chiralpak IA (250 mm 4.6 mm, 5 mm) column. A mixture of acetonitrile, ethanol, n-butyl amine and trifluoro acetic acid in 96:4:0.10:0.16 (v/v/v/v) ratio was used as a mobile phase. The eluted compounds were monitored at 254 nm. Linezolid was subjected to the stress conditions of oxidative, acid, base, hydrolytic, thermal and photolytic degradation. The degradation products were well resolved from main peak and its impurities, proving the stability-indicating power of the method. The developed method was validated as per International Conference on Harmonization (ICH) guidelines with respect to specificity, limit of detection, limit of quantification, precision, linearity, accuracy, robustness and system suitability.

关键词： HPLC Linezolid validation Polar organic mode Stability-indicating

Correct Interpretation of Creep Rates: A Case Study of Cu

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Journal of Materials Science & Technology 2015年第11期31卷 1065-1068页

作者： W.Blum J.Dvoák P.Král P.Eisenlohr v.Sklenika Institut für Werkstoffwissenschaften University of Erlangen-Nürnberg Institute of Physics of Materials Academy of Sciences of the Czech Republic Department of Chemical Engineering and Materials Science Michigan State University

Traditionally the deformation resistance in creep is characterized by the minimum creep rate εmin and its sensitivity to stress （stress exponent n） and temperature （activation energy Q）. various values of constant n have been reported in the literature and interpreted in terms of specific mechanisms. The present case study of coarse-grained Cu at 573 K yields a stress exponent n = 9 for εmin. in tension and a relatively low activation energy. The evolution of the deformation resistance with strain at constant tensile creep load and comparison with creep in compression without fracture indicates that the tensile εmin. result from transition from uniform deformation to strain localization during fracture. This is confirmed by the results of creep in compression where fracture is suppressed. Both the tensile εmin, and the compressive creep rate at strains around 0.3 can be described using existing equations for quasi-stationary deformation containing the subgrain boundary misorientation θ as structure parameter. While in the latter case constant θ leads to monotonic increase of n with stress, the tensile nine-power-law results from variable θ, and has no simple meaning. The result of this case study means that uncritical interpretation of minimum tensile creep rates as stationary ones bears a high risk of systematic errors in the determination of creep parameters and identification of creep mechanisms.

关键词： Cu Creep Minimum creep rate Activation energy Stress exponent

Naturally occurring spike mutations influence the infectivity and immunogenicity of SARS-Cov-2

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Cellular & Molecular Immunology 2022年第11期19卷 1302-1310页

作者： Qiaoli Peng Runhong Zhou Na Liu Hui Wang Haoran Xu Meiqing Zhao dawei Yang ka-Kit Au Haode Huang Li Liu Zhiwei Chen AIDS Institute Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong Special Administrative RegionPR China National Clinical Research Center for Infectious Diseases HKU AIDS Institute Shenzhen Research LaboratoryThe Third People’s Hospital of Shenzhen and The Second Affiliated Hospital of Southern University of Science and TechnologyShenzhenGuangdongPR China Department of Microbiology Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong Special Administrative RegionPR China Centre for virology Vaccinology and Therapeutics LimitedThe University of Hong KongHong Kong Special Administrative RegionPR China HKU AIDS Institute Joint Laboratory Department of Clinical Microbiology and Infection ControlThe University of Hong Kong-Shenzhen HospitalShenzhenGuangdongPR China State Key Laboratory of Emerging Infectious Disease The University of Hong KongHong Kong Special Administrative RegionPR China

Mutations in SARS-Cov-2 variants of concern(vOCs)have enhanced transmissibility and immune evasion with respect to current vaccines and neutralizing antibodies(NAbs).How naturally occurring spike mutations affect the infectivity and antigenicity of vOCs remains to be *** entry efficiency of individual spike mutations was determined in vitro using pseudotyped ***/c mice were immunized with 2-dose DNA vaccines encoding B.1.1.7,B.1.351,B.1.1.529 and their single *** and humoral immune responses were then compared to determine the impact of individual mutations on *** the B.1.1.7 lineage,Del69–70 and Del 144 in NTD,A570D and P681H in SD1 and S982A and D1118H in S2 significantly increased viral entry,whereas T716I resulted in a *** the B.1.351 lineage,L18F and Del 242–244 in the NTD,K417N in the RBD and A701v in S2 also increased viral entry.S982A weakened the generation of binding *** sera showed reduced cross-neutralization activity against B.1.351,B.1.617.2(Delta)and B.1.1.529(Omicron BA.1).S982A,L18F,and Del 242–244 hindered the induction of cross-NAbs,whereas Del 69–70,Del144,R246I,and K417N showed the opposite effects.B.1.351 elicited adequate broad cross-NAbs against both B.1.351 and *** immunogens tested,however,showed low neutralization against circulating *** addition,T-cell responses were unlikely affected by mutations tested in the *** conclude that individual spike mutations influence viral infectivity and vaccine *** vOC-targeted vaccines is likely necessary to overcome immune evasion from current vaccines and neutralizing antibodies.

关键词： SARS-Cov-2 variants of Concern Single mutation neutralizing antibody T cell responses vaccine immunogenicity