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Mass Screening Using Antigenic and Molecular Diagnostic Tests of COVID-19 in Bangui at the Beginning of the Second Wave in July 2021

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Journal of Tuberculosis Research 2024年第1期12卷 1-12页

作者： Clotaire Donatien Rafaï Marie-Roseline Darnycka Belizaire Pierre Somse Wilfrid Sylvain Nambei Ernest Lango-Yaya Oscar Senzongo Luc Salva Hereidebona Ulrich Jeffrey Kotemossoua Rabbi Mermoz Senekian simon Pounguinza Christian-Diamant Mossoro-Kpinde Alain Le Faou Jean De Dieu Longo François-Xavier Mbopi-Keou Gérard Grésenguet Boniface Koffi National Laboratory of Clinical Biology and Public Health Bangui Central African Republic Faculty of Health Sciences University of Bangui Bangui Central African Republic World Health Organization Bangui Central African Republic Ministry of Health and Population Bangui Central African Republic Faculty of Medicine Maieutic and Health Sciences University of Lorraine Pole Brabois Santé Nancy France Faculty of Medicine and Biomedical Sciences University of Yaounde I Yaounde Cameroun

Objective: COVID-19 surveillance was established as early as March 2020 in the Central African Republic (CAR), after the WHO statement relating to the identification of several cases outside China. However, given the non-performing molecular biology technical platform in many developing countries in sub-Saharan Africa, the second wave promised to be surprising and formidable. In this context, a mass survey was launched in Bangui to determine the prevalence of COVID-19. Patients and Methods: From March 18 to April 2, 2021, a mass screening campaign took place in tourist places, companies and the main hospital infrastructures. Nasopharyngeal swab samples were collected from participants with and without symptoms of Influenza-like illness (ILI) and stored in VTM tubes. The Ag (COVID-19) and RT-PCR tests were carried out in Bangui at the LNBCSP. The sequencing of RT-PCR SARS-CoV-2 positives was carried out at the INRB. Results: We included 1480 participants of whom 33 (2.23%) were SARS-COV-2 positive, of whom 24 were male and 9 female. This sex difference was statistically significant (p = 0.012) as the sex ratio M/F was 1.09. Sampling sites located in the 1st arrondissement were the most prolific (p = 0.006) and were sequenced. In addition to the analysis of the 33 samples from the predefined sites under study, 17 control sequences from the provinces generated during the same period are added. We detected 2 Variants Of Concern (VOC) including the predominant B.1.620 (43.86%) followed by B.1.1.7 or Alpha (5.10%). Conclusion: The study showed the importance of surveillance and the availability of means of diagnosis of COVID-19. The identified risk factors were sex and sampling site. This study has shown the importance of setting up sentinel sites for COVID-19 surveillance in all regions of the country and the appropriate use of the anti-COVID-19 vaccine.

关键词： COVID-19 Variants Central African Republic

Learning from the heaviest ancient whale

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The Innovation 2023年第5期4卷 21-22页

作者： Peijun Zhang simon J.Goodman Marine Mammal and Marine Bioacoustics Laboratory Institute of Deep-sea Science and EngineeringChinese Academy of Sciences28 Luhuitou RoadSanya 572000China School of Biology Faculty of Biological SciencesUniversity of LeedsLeeds LS29JTUK

A groundbreaking study published in Nature by Bianucci et *** reported the discovery of a new basilosaurid species,Perucetus colossus(Figure 1).The incomplete fossil skeleton found in Peru is around 39 million years *** ancient whale challenges the long-held belief that the blue whale represents the largest known animal to have ever lived on *** is estimated to have had a body mass between 85 and 340 tons,with an average of 180 tons.1 In comparison,extant blue whales have an estimated body mass of 100–150 *** new study proposes that *** was adapted to a fully aquatic lifestyle in shallow water with slow swimming speeds,similar to extant *** bone mass would have aided buoyancy control while diving to shallow depths,as seen in modern-day *** new discovery not only challenges our understanding of mammalian maximum body mass evolution,but it also expands our knowledge of the lifestyle of ancient cetaceans.

关键词： shallow Figure ancient

Type 2 autoimmune pancreatitis associated with severe ulcerative colitis: Three case reports

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World Journal of Clinical Cases 2022年第24期10卷 8788-8796页

作者： Mark Ghali Karen Bensted David B Williams simon Ghaly Department of Gastroenterology St Vincent's HospitalDarlinghurst 2010NSWAustralia School of Clinical Medicine Faculty of Medicine and HealthThe University of New South WalesSydney 1466NSWAustralia

BACKGROUND Type two autoimmune pancreatitis is a rare and difficult to diagnose,steroid responsive non-IgG4 inflammatory pancreatopathy that can be associated with inflammatory bowel *** SUMMARY This case series describes three cases with varied clinical presentations and representations of autoimmune pancreatitis,and all associated with an aggressive course of ulcerative *** pancreatopathy was independent of bowel disease activity and developed in one case following *** Clinician awareness about this condition is important to allow early diagnosis,treatment and avoid unnecessary pancreatic surgery.

关键词： Autoimmune pancreatitis Inflammatory bowel disease Ulcerative colitis Colectomy Case report

Searching novel complex solid solution electrocatalysts in unconventional element combinations

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Nano Research 2022年第6期15卷 4780-4784页

作者： Olga A.Krysiak simon Schumacher Alan Savan Wolfgang Schuhmann Alfred Ludwig Corina Andronescu Analytical Chemistry-Center for Electrochemical Sciences(CES) Faculty of Chemistry and BiochemistryRuhr University BochumUniversitätsstr.150D-44780 BochumGermany Chemical Technology Ⅲ Faculty of ChemistryCarl-Benz-Straße 199D-47057 DuisburgGermany CENIDE-Center for Nanointegration University Duisburg Essen Carl-Benz-Straße 199D-47057 DuisburgGermany Chair for Materials Discovery and Interfaces Institute for MaterialsFaculty of Mechanical EngineeringRuhr University BochumUniversitätsstr.150D-44780 BochumGermany ZGH Ruhr University BochumUniversitätsstr.150D-44780 BochumGermany

Despite outstanding accomplishments in catalyst discovery,finding new,more efficient,environmentally neutral,and noble metalfree catalysts remains challenging and ***,complex solid solutions consisting of at least five different elements and often named as high-entropy alloys have emerged as a new class of electrocatalysts for a variety of *** multicomponent combinations of elements facilitate tuning of active sites and catalytic *** optimal catalyst composition remains difficult,making testing of a very high number of them *** present the high-throughput screening of the electrochemical activity of thin film material libraries prepared by combinatorial co-sputtering of metals which are commonly used in catalysis(Pd,Cu,Ni)combined with metals which are not commonly used in catalysis(Ti,Hf,Zr).Introducing unusual elements in the search space allows discovery of catalytic activity for hitherto unknown *** libraries with very similar composition spreads can show different activities *** trends for different *** order to address the inherent challenge of the huge combinatorial material space and the inability to predict active electrocatalyst compositions,we developed a high-throughput process based on co-sputtered material libraries,and performed high-throughput characterization using energy dispersive X-ray spectroscopy(EDS),scanning transmission electron microscopy(SEM),X-ray diffraction(XRD)and conductivity measurements followed by electrochemical screening by means of a scanning droplet *** results show surprising material compositions with increased activity for the oxygen reduction reaction and the hydrogen evolution *** data are important input data for future data-driven materials prediction.

关键词： high-entropy alloys electrocatalysis high-throughput screening thin films hydrogen evolution reaction oxygen reduction reaction

Audible noise evaluation for six-phase overhead lines transformed from existing three-phase double circuit infrastructures with uprated voltages

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High Voltage 2022年第5期7卷 866-876页

作者： Qi Li Yanzhou Li simon Rowland Jianlin Hu Ian Cotton Xingliang Jiang State Key Laboratory of Power Transmission Equipment&System Security and New Technology Electrical Engineering SchoolChongqing UniversityChongqingChina Department of Electrical and Electronic Engineering The University of ManchesterManchesterUK

The drive to reduce carbon emissions and meet climate change targets set by governments worldwide has led to the growth of renewable energy sources and electric vehicles in recent *** intermittent generation and centralised demand require increased transmission capacities when operating associated power *** transmission lines are not capable of meeting planned *** many countries,obtaining a new right of way to build an overhead line(OHL)is increasingly *** is therefore an urgent need to study techniques for transmission line *** increasing voltages is not feasible because elevated surface potential gradient at conductor surfaces increases audible noise(AN)levels *** feasibility of high phase order,especially six-phase,transmission techniques has been previously demonstrated,and it has been proved to be an effective way to uprate existing three-phase double circuit OHLs with increased *** study analyses two typical overhead line structures,whose conductor surface potential gradient and AN level are *** average and maximum surface potential gradient of the six-phase OHL are 18.5%and 18.6%lower than that of the three-phase *** AN of the six-phase single circuit OHL is predicted to be 6.33 and 6.45 dBA lower than that of the three-phase double circuit OHL after the voltage is increased by 45%and 50%for the lines *** is shown that six-phase OHLs can increase capacity by allowing elevating phase voltages without increasing acoustic noise levels.

关键词： phase double transformed

Gestational age-specific neonatal mortality in Hong Kong:a population-based retrospective study

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World Journal of Pediatrics 2023年第2期19卷 158-169页

作者： Xue-Lian Wang Eman Leung Genevieve Po Gee Fung Hugh simon Lam Department of Neonatology Guangzhou Women and Children’s Medical CenterGuangzhou Medical UniversityGuangdong Provincial Clinical Research Center for Child HealthGuangzhouChina Department of Paediatrics Faculty of MedicineThe Chinese University of Hong KongHong Kong SARChina The Jockey Club School of Public Health and Primary Care Faculty of MedicineThe Chinese University of Hong KongHong Kong SARChina Department of Paediatrics 6/F Lui Che Woo Clinical Sciences BuildingPrince of Wales HospitalSha TinNew TerritoriesHong Kong SARChina

Background The neonatal period is the most vulnerable period during childhood,with the risk of death being the highest even in developed countries/*** Kong’s neonatal mortality(1‰)is among the world’s lowest and has remained similar for 15 *** study aimed to explore neonatal deaths in Hong Kong in detail and determine whether neonatal mortality is reducible at such a low *** Live births in public hospitals in Hong Kong during 01 Jan 2006–31 Dec 2017 were *** data were extracted from the electronic medical *** age-specific mortality was calculated,and the trends were analyzed using the Cochran–Armitage trend *** of death were summarized,and risk factors were identified in multivariate logistic regression *** In 490,034 live births,755 cases(1.54‰)died during the neonatal period,and 293(0.6‰)died during the post-neonatal *** neonatal mortality remained similar overall(P=0.17)and among infants born at 24–29 weeks’gestation(P=0.4),while it decreased in those born at 23(P=0.04),30–36(P<0.001)and≥37(P<0.001)weeks’*** born at<27 weeks’gestation accounted for a significantly increased proportion among cases who died(27.6%to 51.9%),with hemorrhagic conditions(24%)being the leading cause of *** anomalies were the leading cause of death in neonates born≥27 weeks’gestation(52%),but its cause-specific mortality decreased(P=0.002,0.6‰to 0.41‰),with most of the decrease attributed to trisomy 13/18 and multiple *** Reduction of neonatal mortality in developed regions may heavily rely on improved quality of perinatal and neonatal care among extremely preterm infants.

关键词： Cause of death Neonatal mortality Population based Risk factor Trend

Catalysts for the hydrogen evolution reaction in alkaline medium:Configuring a cooperative mechanism at the Ag-Ag_(2)S-MoS_(2) interface

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Journal of Energy Chemistry 2022年第11期31卷 481-488,I0013页

作者： Avraham Bar-Hen simon Hettler Ashwin Ramasubramaniam Raul Arenal Ronen Bar-Ziv Maya Bar Sadan Department of Chemistry Ben-Gurion University of the NegevBeer-Sheva 8410501Israel Department of Chemistry Nuclear Research Center NegevP.O.Box 9001Beer-Sheva 84190Israel Laboratorio de Microscopías Avanzadas Universidad de Zaragoza50018 ZaragozaSpain Instituto de Nanociencia y Materiales de Aragon CSIC-U.de ZaragozaCalle Pedro Cerbuna 1250009 ZaragozaSpain Department of Mechanical and Industrial Engineering University of MassachusettsAmherstMA 01003United States ARAID Foundation 50018 ZaragozaSpain

Designing electrocatalysts for HER in alkaline conditions to overcome the sluggish kinetics associated with the additional water dissociation step is a recognized challenge in promoting the hydrogen *** this end,delicately tuning the atomic-scale structure and surface composition of nanoparticles is a common strategy and,specifically,making use of hybrid structures,can produce synergistic effects that lead to highly active ***,we present a core-shell catalyst of Ag@MoS_(2)that shows promising results towards the hydrogen evolution reaction(HER)in both 0.5 M H_(2)SO_(4)and 0.5 M *** this hybrid structure,the MoS_(2)shell is strained and defective,and charge transfer occurs between the conductive core and the shell,contributing to the electrocatalytic *** shelling process results in a large fraction of Ag_(2)S in the cores,and adjusting the relative fractions of Ag,Ag_(2)S,and MoS_(2)leads to improved catalytic activity and fast charge-transfer *** suggest that the enhancement of alkaline HER is associated with a cooperative effect of the interfaces,where the Ag(Ⅰ)sites in Ag_(2)S drive the water dissociation step,and the formed hydrogen subsequently recombines on the defective MoS_(2)*** study demonstrates the benefits of hybrid structures as functional nanomaterials and provides a scheme to activate MoS_(2)for HER in alkaline conditions.

关键词： Water splitting Core-shell Catalytic mechanism Electrocatalysis 2D materials

Distributed Secure Storage Scheme Based on Sharding Blockchain

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Computers, Materials & Continua 2022年第3期70卷 4485-4502页

作者： Jin Wang Chenchen Han Xiaofeng Yu Yongjun Ren R.simon Sherratt School of Computer Science and Mathematics Fujian University of TechnologyFuzhou350118China School of Computer&Communication Engineering Changsha University of Science&TechnologyChangsha410004China School of Business Nanjing UniversityNanjing210093China School of Computer School of SoftwareSchool of Cyberspace SecurityEngineering Research Center of Digital ForensicsMinistry of EducationNanjing University of Information Science&TechnologyNanjing210044China Department of Biomedical Engineering University of ReadingRG66AYUK

Distributed storage can store data in multiple devices or servers to improve data ***,in today’s explosive growth of network data,traditional distributed storage scheme is faced with some severe challenges such as insufficient performance,data tampering,and data lose.A distributed storage scheme based on blockchain has been proposed to improve security and efficiency of traditional distributed *** this scheme,the following improvements have been made in this *** paper first analyzes the problems faced by distributed *** proposed to build a new distributed storage blockchain scheme with sharding *** proposed scheme realizes the partitioning of the network and nodes by means of blockchain sharding technology,which can improve the efficiency of data verification between *** addition,this paper uses polynomial commitment to construct a new verifiable secret share scheme called *** new scheme is one of the foundations for building our improved distributed storage blockchain *** with the previous scheme,our new scheme does not require a trusted third party and has some new features such as homomorphic and batch *** security of VSS can be further *** comparisons show that the proposed scheme significantly reduces storage and communication costs.

关键词： Blockchain distributed storage verifiable secret share polynomial commitment

Experimental Investigation on Prototype Latent Heat Thermal Battery Charging and Discharging Function Integrated with Solar Collector

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Energy Engineering 2022年第4期119卷 1587-1610页

作者： Farhood Sarrafzadeh Javadi Hendrik simon Cornelis Metselaar Poo Balan Ganesan Department of Mechanical Engineering Faculty of EngineeringUniversity of MalayaKuala Lumpur50603Malaysia Center of Advanced Materials Faculty of EngineeringUniversity of MalayaKuala Lumpur50603Malaysia

This paper reports the performance investigation of a newly developed Latent Heat Thermal Battery(LHTB)integrated with a solar collector as the main source of *** LHTB is a new solution in the field of thermal storage and developed based on the battery concept in terms of recharge ability,portability and usability as a standalone *** is fabricated based on the thermal battery storage concept and consists of a plate-fin and tube heat exchanger located inside the battery casing and paraffin wax which is used as a latent heat storage *** thermal energy is absorbed by solar collector and transferred to the LHTB using water as Heat Transfer Fluid(HTF).Charging experiments have been conducted with a HTF at three different temperatures of 68°C,88°C and 108°C and three different flow rates of 30,60 and 120 l/*** is followed by discharging experiments on fully charged LHTB at three different temperatures of 68°C,88°C and 108°C using HTF at three different flow rates of 30,60 and 120 l/*** is found that both higher HTF inlet temperature and flow rate have a positive impact on stored thermal ***,charging efficiency was decreased by increasing the HTF flow *** highest charging efficiency of 29%was achieved using HTF of 108°C at a flow rate of 30 l/*** of paraffin melted in this case,while part of the paraffin remained solid in other *** the other hand,the results from discharging experiments revealed that both recovered thermal energy and recovery efficiency increased by either increasing the LHTB temperature or HTF flow *** recovered thermal energy of 5,825 KJ at 35%recovery efficiency achieved at LHTB of 108°C using 120 l/h of HTF.

关键词： Latent heat thermal battery phase change materials solar thermal latent heat storage thermal battery thermal storage