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Serological surveillance for SARS-coV-2 antibodies among students,faculty and staff within a large university system during the pandemic

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World Journal of Virology 2025年第1期14卷 99-107页

作者： marcos G Pinheiro Gabriela G O Alves maria Eduarda R conde Sofia L costa Regina c S Sant’Anna Isa m F Antunes mônica c carneiro Fabio S Ronzei Julia c Scaffo Felipe R Pinheiro Lialyz S Andre Helvecio c Povoa Valéria T Baltar Fabíola Giordani Eduarda S Hemerly Gisele c Alexandre Karla c de Paula márcio Watanabe Antonio claudio L da Nóbrega Jackeline christiane P Lobato Fabio Aguiar-Alves Laboratory of molecular Epidemiology and Biotechnology Rodolpho Albino University LaboratoryFluminense Federal UniversityNiterói 24241000Rio de JaneiroBrazil Estácio de SáUniversity Nova Friburgo 28611135Rio de JaneiroBrazil Pathology Program Medicine schoolFluminense Federal UniversityNiterói 24070090Rio de JaneiroBrazil Department of Pharmaceutical Sciences Lloyd L.Gregory School of PharmacyPalm Beach Atlantic UniversityWest Palm BeachFL 33401United States Health Institute of Nova Friburgo Fluminense Federal UniversityNova Friburgo 28613001Rio de JaneiroBrazil Department of Epidemiology and Biostatistics Institute of Collective Health(ISC)Fluminense Federal UniversityNiterói 24033900Rio de JaneiroBrazil Institute of Physical Education Fluminense Federal UniversityNiterói 24020005Rio de JaneiroBrazil Department of Statistics Fluminense Federal UniversityNiterói 24210200Rio de JaneiroBrazil Department of Physiology and Pharmacology Fluminense Federal UniversityNiterói 24210130Rio de JaneiroBrazil

BAcKGROUND At the end of December 2019,the world faced severe acute respiratory syndrome-coronavirus 2(SARS-coV-2),which led to the outbreak of coronavirus disease 2019(cOVID-19),associated with respiratory *** virus has shown significant challenges,especially for senior citizens,patients with other underlying illnesses,or those with a sedentary *** tests conducted early on have helped identify how the virus is transmitted and how to curb its *** study hypothesis was that the rapid serological test for SARS-coV-2 antibodies could indicate the immunoreactive profile during the cOVID-19 pandemic in a university *** To conduct active surveillance for serological expression of anti-SARS-coV-2 antibodies in individuals within a university setting during the cOVID-19 *** This sectional study by convenience sampling was conducted in a large university in Niteroi-RJ,Brazil,from march 2021 to July *** study population consisted of students,faculty,and administrative staff employed by the university.A total of 3433 faculty members,60703 students,and 3812 administrative staff were invited to *** were gathered through rapid serological tests to detect immunoglobulin(Ig)m and IgG against ***χ²or Fisher's exact test was used to conduct statistical analysis.A 0.20 significance level was adopted for variable selection in a multiple logistic regression model to evaluate *** A total of 1648 individuals were enrolled in the *** proportion of cOVID-19 positivity was 164/1648(9.8%).The adjusted logistic model indicate a positive association between the expression of Igm or IgG and age[odds ratio(OR)=1.16,95%cI:1.02-1.31](Pcontact with a cOVID-19-positive case(OR=3.49,95%cI:2.34-5.37)(Pceived the cOVID-19 vaccine(OR=2.33,95%cI:1.61-3.35)(Pcial isolation(OR=0.59,95%cI:0.41-0.84)(P<0.004).The likelihood of sho

关键词： Serological surveillance SARS-coV-2 antibodies cOVID-19 Serological rapid test Risk factors for cOVID-19

Fragmentation patterns and systematic transitions of the forested landscape in the upper Amazon region, Ecuador 1990-2008

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Journal of Forestry Research 2014年第2期25卷 301-309页

作者： Santiago Bonilla-bedoya Juan R.molina José E.macedo-Pezzopane miguel A.Herrera-machuca DepartaTento de Ingeniería Forestal E.T.S.I.A.M.Universidad de CórdobaCaTpus de Excelencia Internacional Agroali Tentario (ceiA3) Secretaria Nacional de Educación Superior CienciaTecnología e Innovación del EcuadorWhy Tper E7-37 y Alpallana Quito. Ecuador Departa Tento de Engenharia Florestal Universidade Federal do Espírito Santo

The analysis of the systematic transitions in the forested landscape and the study of the forest fragmentation patterns allow us to deepen our understanding of the changes in the vegetation ground cover. The importance of knowing the intricate patterns of the land usage of the upper basin of the Amazon region is widely recognized. This zone is one of the most diverse biological areas in the world, is home to large areas of mature tropical cloud forest and demonstrates high probabilities of stable climatic conditions in light of global warming. The research quan- tiffed systematic transitions through the ＂loss＂ and ＂gain＂ of the different categories of landscape during the eighteen-year study period of the Ecuadorian Amazon Region （EAR）, the forest fragmentation patterns were also analyzed based on a set of indicators. Therefore, with respect to the entirety of the landscape, the results registered for the ground coverage in forested areas during the first period （1990-2000）, show a decrease of 6.99% and an increase of 0.68%; and during the second period （2000-2008）, show a decrease of 3.99% and an increase of 2.14%. It demonstrated that forest and agricultural areas tended to replace or be replaced by herbaceous vegetation faster than expected fortuitously. Finally, the indices of fragmentation signaled intense changes during the 1990-2000 period with a reduction during the period 2000-2008. Per- centages registered in the Largest Patch Index （LPI） were between 79.58%; 52.39% and 49.99% respectively; while the Patch Density （PD） varied between 0.04; 0.06 and 0.07. This suggests the propensity of for- est cover to remain intact. The results of this investigation suggest a tendency towards stability in Ecuador＇s Amazon landscape. Within the framework for development and management of this area, the tendency is natural regeneration. This permits a consolidation of the conservation, reforestation, forestation and agricultural forestry plans, programs and systems for the

关键词： Ecuadorian Amazon systematic transitions fragmentation natural regeneration

Regulation of mitochondrial function and endoplasmic reticulum stress by nitric oxide in pluripotent stem cells

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World Journal of Stem cells 2017年第2期9卷 26-36页

作者： Estefania caballano-Infantes José Terron-Bautista Amparo Beltrán-Povea Gladys m cahuana Bernat Soria Hajji Nabil Francisco J bedoya Juan R Tejedo Andalusian center for molecular Biology and Regenerative medicine-University Pablo de Olavide 41092 SevilleSpain Biomedical Research Network on Diabetes and Related metabolic Diseases(cIBERDEm) Instituto de Salud CarlosⅢ28029 MadridSpain Andalusian center for molecular Biology and Regenerative medicine(cABImER) 41092 SevilleSpain Andalusian center for molecular Biology and Regenerative medicine Fundación Progreso y Salud41092 SevilleSpain centre for Pharmacology and Therapeutics Division of Experimental MedicineImperial College LondonHammersmith Hospital CampusLondon W12 0NNUnited Kingdom

mitochondrial dysfunction and endoplasmic reticulum stress(ERS) are global processes that are interrelated and regulated by several stress factors. Nitric oxide(NO) is a multifunctional biomolecule with many varieties of physiological and pathological functions, such as the regulation of cytochrome c inhibition and activation of the immune response, ERS and DNA damage; these actions are dose-dependent. It has been reported that in embryonic stem cells, NO has a dual role, controlling differentiation, survival and pluripotency, but the molecular mechanisms by which it modulates these functions are not yet known. Low levels of NO maintain pluripotency and induce mitochondrial biogenesis. It is well established that NO disrupts the mitochondrial respiratory chain and causes changes in mitochondrial ca^(2+) flux that induce ERS. Thus, at high concentrations, NO becomes a potential differentiation agent due to the relationship between ERS and the unfolded protein response in many differentiated cell lines. Nevertheless, many studies have demonstratedthe need for physiological levels of NO for a proper ERS response. In this review, we stress the importance of the relationships between NO levels, ERS and mitochondrial dysfunction that control stem cell fate as a new approach to possible cell therapy strategies.

关键词： Endoplasmic reticulum stress mitochondrial function Nitric oxide Pluripotency cell differentiation mitochondrial biogenesis

Butt-welding Residual Stress of Heat Treatable Aluminum Alloys

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Journal of materials Science & Technology 2007年第2期23卷 217-222页

作者： c.m. cheng Department of Industrial Education National Taiwan Normal University Taipei Taiwan China　

This study, taking three types of aluminum alloys 2024-T351, 6061-T6 and 7075-T6 as experimental materials, conducted single V-groove GTAW （gas tungsten arc welding） butt-welding to analyze and compare the magnitude and differences of residual stress in the three aluminum alloys at different single V-groove angles and in restrained or unrestrained conditions. The results show that the larger the grooving angle of butt joint, the higher the residual tensile stress. Too small grooving angle will lead to dramatic differences due to the amount of welding bead filler metal and pre-set joint geometry. Therefore, only an appropriate grooving angle can reduce residual stress. While welding, weldment in restrained condition will lead to a larger residual stress. Also, a residual stress will arise from the restraint position. The ultimate residual stress of weldment is determined by material yield strength at equilibrium temperature. The higher the yield strength at equilibrium temperature, the higher the material residual stress. Because of its larger thermal conductivity, aluminum alloy test specimens have small temperature differential. Therefore, the residual tensile stress of all materials is lower than their yield strength.

关键词： Residual stress Hole-drilling strain-gage method Aluminum alloy Single-V groove

Detection of Breaking Waves Using X-Band Pulse Radar in the Nearshore Region

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china Ocean Engineering 2013年第4期27卷 549-556页

作者： Y.c.Lin c.c.chang m.c.Lee H.c.chan J.m.Leu Department of Hydraulic and Ocean Engineering National Cheng-Kung University Department of Soil and Water conservation National Chung Hsing University Department of Hospitality management Taiwan Shoufu University

An X-band pulsed Doppler microwave radar has been used to determine the characteristics of breaking waves. Field experiments were conducted at the Shuang-Si estuary in the north of Taiwan in the winter of 2005. Analyses on maxima radar cross section and Doppler frequency shift are done to characterize wave breaking zones. Based on observations of breaking waves, the wave breaking zones are shown to be located at water depths of 1.8 to 2.2 m in the experimental site. In general, the results indicate that a radar system has the potential to delineate the spatial variation of breaking waves clearly and that this is sufficient to achieve a measurement operation for near-shore air-sea interaction events.

关键词： radar Doppler effect wave breaking coastal zone

A large epeiric methanogenic Bambuí sea in the core of Gondwana supercontinent?

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Geoscience Frontiers 2021年第1期12卷 203-218页

作者： Sergio caetano-Filho Pierre Sansjofre magali Ader Gustavo m.Paula-Santos cristian Guacaneme marly Babinski carolina bedoya-Rueda matheus Kuchenbecker Humberto L.S.Reis Ricardo I.F.Trindade Universidade de Sao Paulo Instituto de GeocienciasRua do Lago562-Sao Paulo05508-080Brazil mNHN Sorbonne UniversiteCNRS UMR 7590Institut de Mineralogiede Physique des Materiaux et de Cosmochimie75005ParisFrance Universite de Paris Institut de Physique du Globe de ParisCNRSF-75005ParisFrance Universidade Estadual de campinas Instituto de GeocienciasRua Carlos Gomes250-Campinas13083-855Brazil Universidade Federal dos Vales do Jequitinhonha e mucuri Instituto de Ciencia e TecnologiaLaboratorio de Estudos TectonicosRodovia MGT 367Km 583-Diamantina39100-000Brazil Universidade Federal de Ouro Preto Departamento de Geologia-Escola de MinasLaboratiorio de Modelagem TectonicaCampus Morro do Cruzeiro-Ouro Preto35400-000Brazil Universidade de Sao Paulo Instituto de AstronomiaGeofísica e Ciencias AtmosfericasRua do Matao1226-Sao Paulo05508-090Brazil

carbon isotope compositions of both sedimentary carbonate and organic matter can be used as key proxies of the global carbon cycle and of its evolution through time,as long as they are acquired from waters where the dissolved inorganic carbon(DIc)is in isotope equilibrium with the atmospheric ***,in shallow water platforms and epeiric settings,the influence of local to regional parameters on carbon cycling may lead to DIG isotope variations unrelated to the global carbon *** may be especially true for the terminal Neoproterozoic,when Gondwana assembly isolated waters masses from the global ocean,and extreme positive and negative carbon isotope excursions are recorded,potentially decoupled from global *** improve our understanding on the type of information recorded by these excursions,we investigate the pairedδ^13ccarb andδ^13corg evolution for an increasingly restricted late Ediacaran-cambrian foreland system in the West Gondwana interior:the basal Bambui *** succession represents a 1~(st)-order sedimentary sequence and records two majorδ^13ccarb excursions in its two lowermost lower-rank *** basal cap carbonate interval at the base of the first sequence,deposited when the basin was connected to the ocean,hosts antithetical negative and positive excursions forδ^13ccarb andδ^13corg,respectively,resulting inΔ^13c values lower than 25‰.From the top of the basal sequence upwards,an extremely positiveδ^13ccarb excursion is coupled toδ^13corg,reaching values of+14‰and-14‰,*** positive excursion represents a remarkable basin-wide carbon isotope feature of the Bambui Group that occurs with only minor changes inΔ^13c values,suggesting change in the DIc isotope *** argue that this regional isotopic excursion is related to a disconnection between the intrabasinal and the global carbon *** extreme carbon isotope excursion may have been a product of a disequilibria between the basin DIc and atmospheric cO2

关键词： methanogenesis Ediacaran cambrian carbon isotopes Sao Francisco Basin Bambui Group

Role of nitric oxide in the maintenance of pluripotency and regulation of the hypoxia response in stem cells

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World Journal of Stem cells 2015年第3期7卷 605-617页

作者： Amparo Beltran-Povea Estefania caballano-Infantes carmen Salguero-Aranda Franz martín Bernat Soria Francisco J bedoya Juan R Tejedo Gladys m cahuana Andalusian center for molecular Biology and Regenerative medicine-University Pablo de Olavide CIBERDEM RED-TERCEL 41092 Seville Spain Andalusian center for molecular Biology and Regenerative medicine (cABImER) -Fundación Progreso y Salud CIBERDEM RED-TERCEL 41092 Seville Spain

Stem cell pluripotency and differentiation are global processes regulated by several pathways that have been studied intensively over recent years. Nitric oxide(NO) is an important molecule that affects gene expression at the level of transcription and translation and regulates cell survival and proliferation in diverse cell types. In embryonic stem cells NO has a dual role, controlling differentiation and survival, but the molecular mechanisms by which it modulates these functions are not completely defined. NO is a physiological regulator of cell respiration through the inhibition of cytochrome c oxidase. many researchers have been examining the role that NO plays in other aspects of metabolism such as the cellular bioenergetics state, the hypoxia response and the relationship of these areas to stem cell stemness.

关键词： Pluripotency Differentiation Nitric oxide metabolism Hypoxia Stem cell

mixing features in an electromagnetic rectangular micromixer for electrolyte solutions

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Journal of Hydrodynamics 2017年第4期29卷 668-678页

作者： m.m.Wen c.N.Kim Department of mechanical Engineering Graduate School Kyung Hee University Department of mechanical Engineering College of Engineering Kyung Hee University

In this study, a new magnetohydrodynamic（mHD） mixer for electrolyte solutions with pumping function is reported, and the mixing performance of the device for two different electrolyte solutions is numerically examined in a uniform magnetic field. Application of different potentials to different electrodes allows the current to be induced. The combination of the induced current and magnetic field yields Lorentz force, resulting in the fluid motion. The numerical simulation for the flows in the device is carried out with commercial software cFX. The validity of cFX code for the present numerical model is presented. The mixing performance of the fluids is investigated in many different cases with different combinations of input voltage of the electrode. This study shows that the mixing performance can be enhanced by applying spatially alternating positive and negative voltages to the electrodes. The present simulation results show that with a magnetic field intensity lower than 0.5 T, a voltage difference smaller than 2.0 V, and an electric conductivity of electrolyte solution of 1.5 S/m the pumping capabilities ranging 1.6×10^（-7）-3.6×10^（-6） kg/s and the mixing indexes higher than 0.90 can be obtained with sophisticated designs of the micromixer.

关键词： mixer electrolyte solution Lorentz force cFX

Hard rock tunnel boring machine penetration test as an indicator of chipping process efficiency

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Journal of Rock mechanics and Geotechnical Engineering 2017年第4期9卷 611-622页

作者： m.c. Villeneuve Department of Geological Sciences University of Canterbury Christchurch 8140 New Zealand

The transition from grinding to chipping can be observed in tunnel boring machine(TBm) penetration test data by plotting the penetration rate(distance/revolution) against the net cutter thrust(force per cutter) over the full range of penetration rates in the *** penetration test data to the geological and geomechanical characteristics of rock masses through which a penetration test is conducted provides the ability to reveal the efficiency of the chipping process in response to changing geological *** test data can also be used to identify stress-induced tunnel face *** research shows that the strength of the rock is an important parameter for controlling how much net cutter thrust is required to transition from grinding to *** also shows that the geological characteristics of a rock will determine how efficient chipping occurs once it has *** particular,geological characteristics that lead to efficient fracture propagation,such as fabric and mica contents,will lead to efficient *** findings will enable a better correlation between TBm performance and geological conditions for use in TBm design,as a basis for contractual payments where penetration rate dominates the excavation cycle and in further academic investigations into the TBm excavation process.

关键词： Penetration rate Grinding chipping Geological characteristics Face stability