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Contribution of Genomic Surveillance in the Detection and Monitoring of SARS-CoV-2 Variants during the 6 Pandemic Waves in the Central African Republic from 2020 to 2023

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Journal of Tuberculosis Research 2024年第3期12卷 151-164页

作者： Clotaire Donatien Rafaï Ernest Lango-Yaya Marie Roseline Darnicka Belizaire Ouoko Fa-Ti-Gbia Maurel Annicet Adonis Marcel Mbeko Simaleko Jean-Baptiste Roungou Oscar Senzongo karl G. Njuwa Fai Boniface Koffi National Laboratory of Clinical Biology and Public Health of Bangui Bangui Republic Central African University of Bangui Bangui Central African Republic World Health Organization Geneva Switzerland Ministry of Health and Population Bangui Central African Republic Africa CDC Addis-Abeba Ethiopia Homegrown Solutions for Health Yaounde Cameroon

Objective: The COVID-19 pandemic has highlighted the need to strengthen diagnosis and genomic surveillance capacities. In 2021, Central African managed five waves of COVID-19 by integrating genomic surveillance into their health monitoring system. This study sought to report surveillance data from the National Laboratory of Clinical Biology and Public Health and describe the circulation of SARS-CoV-2 variants. Materials and Methods: This retrospective, descriptive observational study spans three years, from April 2020 to November 2023. It was conducted on a population of consenting volunteers from across the Central African Republic, who were tested using RT-PCR on nasopharyngeal samples. Data with sufficient information were obtained from the National Laboratory of Clinical Biology and Public Health (LNBCSP) databases. Sequencing was largely carried out at the National Institute of Biomedical Research (INRB) in Kinshasa until May 2023, and subsequently at the LNBCSP. Results and Discussion: Out of 97,864 RT-PCR tests performed, 9,764 were positive, resulting in a prevalence of 9.98%. The average age of the patients was 39.97 years ± 13.76, and the male-to-female sex ratio was 2.12. RT-PCR test positivity was significantly associated with age (p = 0.001), sex (p = 0.013) and clinical manifestations. Ten variants circulated during the five recorded waves, with Omicron (B.1.1.529), Delta (B.1.617.2) variants being predominant. Notably, the B.1.620 and B.640 variants were prominent during the second wave. Conclusion: This retrospective study provides key insights into the COVID-19 pandemic in the CAR. It identifies risk factors and details the circulation of various SARS-CoV-2 variants. Enhancing national genomic surveillance capacities would enable the country to better respond to future pandemic challenges.

关键词： SARS-CoV-2 Variants Central African Republic RT-PCR

Investigation of Cathode Catalysts for Intermediate-temperature H2S-Air Fuel Cells

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Chinese Journal of Chemical Engineering 2007年第3期15卷 305-308页

作者：钟理罗京莉 karl Chuang College of Chemical and Energy Engineering South China University of Technology Guangzhou 510640 China Department of Chemical and Materials Engineering University of Alberta Edmonton AB T6G 2G6 Canada

Abstract Cathode catalysts comprising composite NiO, NiO-Pt, or LiNiO2 have been developed for electro- chemical oxidation of hydrogen sulfide in intermediate-temperature solid oxide fuel cells （ITSOFCs）. All catalysts exhibited good electrical conductivity and catalytic activity at operating temperature. Composite NiO catalysts were found to be more active and have lower over potential and higller current density than pure Pt although the electrical conductivity of NiO itself is lower than that of Pt. This problem has been overcome by either admixing as high as 10% （by mass）Ag powder into NiO_ cathode layer or using composite NiO c atalysts such as NiO-Pt and LiNiO2 catalysts. Composite catalysts like NiO with Ag, electrolyte and starch admixed, NiO-Pt, which was prepared from a mixture of NiO and Pt powders, by admixing electrolyte and starch, and LiNiO2, which is derived from the reaction of LiOH-H2O and NiO with electrolyte and starch admix_ed have been shown to be feasible and effective in an intermediate-temperature H2S-air fuel cell. A fuel cell using Li2SO4-based proton-conducting membrane as electrolyte, metal sulfides as anode catalysts, and composite NiO as cathode catalysts produced a maximum current density about 300mA·cm^-2 and maximum power density over 80 mW-cm-2 at 680℃.

关键词： cathode catalyst fuel'cell hydrogen sulfide

Prevalence and Determinants of Traditional,Complementary and Alternative Medicine Provider Use among Adults from 32 Countries

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Chinese Journal of Integrative Medicine 2018年第8期24卷 584-590页

作者： karl Peltzer Supa Pengpid Southeast Asian Nations (ASEAN) Institute for Health Development Mahidol University Department of Research and Innovation University of LimpopoTurfloop Campus HIV/AIDS/STIs and TB (HAST) Human Sciences Research Council

Objective： To estimate recent prevalence data（2011-2013） on traditional,complementary and alternative medicine（TCAM） provider use and sociodemographic and health related correlates in nationally representative population samples from 32 countries from all world ***： This secondary analysis was based on the International Social Survey Program（ISSP）,2011-2013,Health and Health Care *** a cross-sectional population-based survey（N=52,801）,simple or multi-stage stratified random sampling was used,resulting in representative samples of the adult population of respective ***： Overall,the 12-month TCAM provider use prevalence was 26.4%,ranging from under 10% in Bulgaria,Poland and Slovenia to over 50% in China mainland,the Philippines and Republic of *** 80% TCAM treatment satisfaction was found in Europe in Denmark,Slovenia,Spain and Switzerland,in Asia in Taiwan（China） and *** logistic regression found sociodemographic variables（middle age,female sex,lower educational status,not having a religious affiliation,and lower economic indicators） and health variables（perceived poor or fair health status,being unhappy and depressed,having a chronic condition or disability,and having positive attitudes towards TCAM） were associated with TCAM provider ***： A high prevalence TCAM provider use was found in all world regions and several sociodemographic and health related factors of its use were identified.

关键词： utilization traditional complementary medicine Africa Asia America Australia Europe

Forming Process of Strong Anisotropic Material Based on the Hydrodynamic Deep Drawing with Radial Pressure

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Journal of Materials Science & Technology 2005年第5期21卷 733-737页

作者： Joachim DANCKERT karl Brian NIELSEN Department of Production Aalborg University Fibigerstraede 16 DK-9220Aalborg DenmarkDepartment of ProductionAalborg University Fibigerstraede 16 DK-9220Aalborg Denmark

The hydrodynamic deep drawing process enables net shape or near net shape forming of complicated sheet metal parts made from difficultly forming materials, such as aluminium or high strength steels. Based on the conventional hydrodynamic deep drawing process, a new process, hydrodynamic deep drawing process, in which radial pressure is applied to the rim of the blank, is proposed. This new process has been analysed using FEM simulations and the obtained results have been compared with the experimental results. The material used in the experiments was Al-Mg-Si alloy, and in the FEM-simulations the elastic-plastic behaviour of Al-Mg-Si alloy was modelled using Barlat＇s 89 yield criteria.

关键词： Hydroforming Hydrodynamic deep draw Simulation Aluminum alloy

Interaction phenomena between liquid droplets and hot particles—Captured via high-speed camera

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Particuology 2009年第4期7卷 260-263页

作者： Sebastian Gehrke karl-Ernst Wirth Institute of Particle Technology Cauerstrasse 4Erlangen 91058Germany

The interaction of evaporating droplets and hot catalyst particles plays a major role in heterogeneously catalysed reactions. The liquid feed is injected into a gas-solid flow and is mixed with the catalyst. The interaction phenomena determine the evaporation time which should be minimised to keep the reactor vessel small. First measurements with a bed of fixed hot FCC-particles （fluid catalytic cracking） and two model fluids have been conducted. The interactions of ethanol and water droplets with the hot bed surface were captured via a high-speed camera. While the ethanol droplet developed a stable steam cushion due to Leidenfrost phenomena, water showed intense interaction and steam explosions which induced repulsion and atomisation of the droplet.

关键词： Particle-droplet-interaction Leidenfrost phenomenon Direct heat transfer Liquid-feed-injection

Overview of Particles and Bubbles in Continuously Cast Steel

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Journal of Iron and Steel Research International 2011年第S2期18卷 211-219页

作者： karl-Hermann TACKE AG der Dillinger Hüttenwerke P.O. Box 1580 D-66748 Dillingen/Saar Germany

This paper gives an overview of phenomena associated with particles and bubbles in continuously cast steel. During steel processing from deoxidation to solidification the inclusion population undergoes changes with opportunities of removal. Flotation is an important separation mechanism. Inclusion particles may accumulate in the solidifying strand, thus forming enriched bands, which depend on the type of casting machine. Bubbles are created during inert gas injection. They also change in size, can float out, but also form accumulation bands. The interaction of bubbles and particles is discussed. Internal structure that recently has been observed on the inner surface of bubbles will be reviewed.

关键词： continuous casting solidification inclusions particles agglomeration accumulation bands gas injection bubbles attachment flotation inner surface wave rings terraces

Holographic topological semimetals

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Science China(Physics,Mechanics & Astronomy) 2020年第5期63卷 6-30页

作者： karl Landsteiner Yan Liu Ya-Wen Sun Instiuto de Fisica Teorica UAM/CSIC C/Nicolas Cabrera 13-15Campus CantoblancoCantoblanco 28049Spain Center for Gravitational Physics Department of Space ScienceBeihang UniversityBejing 100191China Key Laboratory of Space Environment Monitoring and Information Processing Ministry of Indusry and Information Technology.Beijing 100191China School of Physics&CAS Center for Excllence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100049China Kavli Institute for Theoretical Sciences University of Chinese Academy of SciencesBeijing 100049China

The holographic duality allows to construct and study models of strongly coupled quantum matter via dual gravitational *** general such models are characterized by the absence of quasiparticles, hydrodynamic behavior and Planckian dissipation times. One particular interesting class of quantum materials are ungapped topological semimetals which have many interesting properties from Hall transport to topologically protected edge states. We review the application of the holographic duality to this type of quantum matter including the construction of holographic Weyl semimetals, nodal line semimetals, quantum phase transition to trivial states(ungapped and gapped), the holographic dual of Fermi arcs and how new unexpected transport properties,such as Hall viscosities arise. The holographic models promise to lead to new insights into the properties of this type of quantum matter.

关键词： gauge/gravity duality topological semimetal Weyl semimetal anomaly

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库夫施泰因在童话世界和无垠山野共振

环球人文地理 2024年第11期 144-152页

作者：十一 ARochau Erika karl Allen Lugmayer Nikolai Sorokin Olivier pictureserver Roman Babakin Stephan Sühling Thomas Gross 摄图网

欧洲最适合隐居的地方在哪里？近日Lonely Planet公布的名单中，阿尔卑斯山脚下的库夫施泰因榜上有名。古典音乐环绕小镇，而走进大自然的方式有无数种：夏季徒步，冬季滑雪……库夫施泰因，奥地利西部的一个美丽小镇。得益于德、奥边...

欧洲最适合隐居的地方在哪里？近日Lonely Planet公布的名单中，阿尔卑斯山脚下的库夫施泰因榜上有名。古典音乐环绕小镇，而走进大自然的方式有无数种：夏季徒步，冬季滑雪……库夫施泰因，奥地利西部的一个美丽小镇。得益于德、奥边界的地理之势，无论从慕尼黑还是萨尔茨堡出发，都只需乘车约1小时就能到达。小镇夹在阿尔卑斯山的一个河谷，碧绿草坪、原始森林和清澈湖水环绕四周，八个村庄点缀其间，从高空俯瞰，犹如散落的珍珠。

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Influence of Metal Sulfides as Anode Catalysts on Performance of H_2S SOFC

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Chinese Journal of Chemical Engineering 2003年第3期11卷 245-248页

作者：钟理刘曼韦国林 CHUANG karl College of Chemical Engineeering South China University of TechnologyGuangzhou 510640China Department of Chemical and Materials Engineering University of AlbertaEdmontonAlbertaCanada

Two anode catalysts with Pt, MoS2 and composite metal sulfides (MoS2+NiS), are investigated for electrochemical oxidation of hydrogen sulfide in solid oxide fuel cell (SOFC) at temperatures 750-850℃. The catalysts comprising MoS2 and MoSa+NiS exhibited good electrical conductivity and catalytic activity. MoS2 and composite catalysts were found to be more active than Pt, a widely used catalyst for high temperature H2S/O2 fuel cell at 750-850℃. However, MoS2 itself sublimes above 450℃. In contrast, composite catalysts containing both Mo and transition metal (Ni) are shown to be stable and effective in promoting the oxidation of H2S in SOFC up to 850℃. However, electric contact is poor between the platinum current collecting layer and the composite metal sulfide layer, so that the cell performance becomes worse. This problem is overcome by adding conductive Ag powder into the anode layer (forming MoS2+NiS+Ag anode material) to increase anode electrical conductance instead of applying a thin layer of platinum on the top of anode.

关键词： solid oxide fuel cell (SOFC) hydrogen sulfide metal sulfide anode