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f(G,T) Gravity with Cylindrically Symmetric Relativistic Fluids

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Communications in Theoretical Physics 2019年第2期71卷 220-230页

作者： M.Farasat shamir M.Awais Sadiq Department of Sciences and Humanities National University of Computer and Emerging SciencesLahore CampusLahorePakistan

The aim of this paper is to examine the structure scalars with account of f(G, T) theory of gravity. We consider the cylindrically symmetric spacetime with dissipative anisotropic background. We have determined the structure scalars by orthogonally decomposing the Riemann curvature tensor and it is shown that these scalars are associated with fundamental properties of fluid. We further investigate the mass function along with the transport equation and discuss their role on the evolutionary stages of relativistic stellar systems. We have also analyzed these structure scalars for static fluid distributions and it is concluded that all possible solutions of field equations can be expressed through these scalars.

关键词： f(G,T) gravity cylindrically symmetric spacetime structure scalars

Estimating the subsolar magnetopause position from soft X-ray images using a low-pass image filter

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Earth and Planetary Physics 2024年第1期8卷 173-183页

作者： Hyangpyo Kim Hyunju K.Connor Jaewoong Jung Brian M.Walsh David Sibeck Kip D.Kuntz Frederick S.Porter Catriana K.Paw u Rousseau A.Nutter Ramiz Qudsi Rumi Nakamura Michael Collier Space Research Institute Austrian Academy of Sciences8042 GrazAustria Geophysical Institute University of Alaska FairbanksFairbanksAlaska 99775USA National Aeronautics and Space Administration(NASA)Goddard Space Flight Center GreenbeltMaryland 20771USA Astronomy Department University of Maryland College ParkCollege ParkMaryland 20742USA Center for Space Physics Boston UniversityBostonMassachusetts 02215USA Department of Physics and Astronomy Johns Hopkins UniversityBaltimoreMaryland 21218USA Howard university WashingtonDC 20059USA

The Lunar Environment heliospheric X-ray Imager(LEXI)and Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)missions will image the Earth’s dayside magneto pause and cusps in soft X-rays after their respective launches in the near future,to specify glo bal magnetic reconnection modes for varying solar wind *** suppo rt the success of these scientific missions,it is critical to develop techniques that extract the magnetopause locations from the observed soft X-ray *** this research,we introduce a new geometric equation that calculates the subsolar magnetopause position(RS)from a satellite position,the look direction of the instrument,and the angle at which the X-ray emission is *** assumptions are used in this method:(1)The look direction where soft X-ray emissions are maximized lies tangent to the magnetopause,and(2)the magnetopause surface near the subsolar point is almost spherical and thus RSis nea rly equal to the radius of the magneto pause *** create synthetic soft X-ray images by using the Open Geospace General Circulation Model(OpenGGCM)global magnetohydrodynamic model,the galactic background,the instrument point spread function,and Poisson *** then apply the fast Fourier transform and Gaussian low-pass filte rs to the synthetic images to re move noise and obtain accurate look angles for the soft X-ray pea *** the filte red images,we calculate RS and its accuracy for different LEXI locations,look directions,and solar wind densities by using the OpenGGCM subsolar magnetopause location as ground *** method estimates RS with an accuracy of10 *** accuracy improves for greater solar wind densities and during southward interplanetary magnetic *** method ca ptures the magnetopause motion during southwa rd interplaneta ry magnetic field ***,the technique will enable quantitative analysis of the magnetopause motion and help reveal the daysi

关键词： soft X-ray magnetopause reconnection low-pass filter LEXI SMILE

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论意思表示公告方式选择与生效的双层构造

法学论坛 2024年第3期39卷 133-142页

作者：寇枫阳吉林大学法学院吉林长春130012

意思表示公告方式学说的单一化思维,产生了实践需求与理论无奈之张力。不同于私法上的其他公告,意思表示公告方式承载了私法自治工具的制度功能。意思表示生效时点的体系解释表明,公告方式适用于所有意思表示类型。因而参照《民事诉讼... 详细信息

意思表示公告方式学说的单一化思维,产生了实践需求与理论无奈之张力。不同于私法上的其他公告,意思表示公告方式承载了私法自治工具的制度功能。意思表示生效时点的体系解释表明,公告方式适用于所有意思表示类型。因而参照《民事诉讼法》公告送达制度的多数说,不符合《民法典》第139条的文义与体系。合理的解释方向是,在尊重公告方式选择自由的基础上,通过生效控制原理避免公告方式的滥用。我国公告实践发展出的禁止增加负担的效力控制标准,可合理分配选择自由之风险。在该风险分配模式下,公告方式的限制类型分为法定负担情形下的主体限制、意定负担情形下的媒介限制、单方增加负担情形下类推适用《诉讼时效司法解释》第8条第1款第4项的限制、无相对人与单方加利情形下的无限制。

关键词：意思表示公告方式公告送达方式自由效力控制风险分配

The COVID-19 Pandemic: Present or Gone, Where Do Adolescents Stand?

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Advances in Infectious Diseases 2024年第2期14卷 374-386页

作者： Ifueko Enadeghe Ayebo Sadoh Emmanuel u. Eyo-Ita Phillip O. Abiodun Department of Child Health University of Benin Teaching Hospital Benin City Nigeria Institute of Child Health University of Benin Benin City Nigeria

Introduction: The initial global response to the SARS-CoV-2 pandemic focused on adults as adolescents mainly had subclinical infections. Adolescents, however, could transmit the virus and hence be a risk to the elderly, young children and immunocompromised. Adolescents are also at risk of long-term complications. This study sought to determine the prevalence of antibodies to SARS-CoV-2 among adolescents in Southern Nigeria, and to determine the association between SARS-CoV-2 seropositivity and age, gender, socioeconomic class, school type and nutritional status. Methods: This descriptive cross-sectional study was carried out in Edo state of southern Nigeria. We recruited 270 in-school adolescents aged 10 - 19 years. A WHO-adapted, pre-tested questionnaire was used to obtain data on participant history and risk factors. The questionnaire was interviewer-administered. Adolescents whose parents gave consent were recruited through a multi-stage randomized sampling method. Capillary blood for the assay was collected and analysed using a lateral-flow immunoassay device. The primary outcome was serostatus of the study. The positive predictors of serostatus were finally determined using a multiple logistics regression model. Statistical significance was set at p Results: The seroprevalence of SARS-CoV-2 was 45.9%. IgM antibodies were found in 5.6% of participants. Older adolescents had higher seropositivity rates than younger adolescents (2 = 8.101, p = 0.017). There was no association between gender and seropositivity. Adolescents in public schools were more likely to be seropositive than those in private schools (2 = 25.242, p = 0.001). A higher seroprevalence was noticed among study participants in the lower socioeconomic class (x2 = 6.928, p = 0.031), and those in overcrowded classes. (2 = 79.303, p = 0.001). Conclusion: This study showed a high seroprevalence of SARS-CoV-2 among in-school adolescents. Behavioural change communication on SARS-CoV-2, vaccination of adole

关键词： Pandemic Adolescents Seroprevalence COVID-19

Generation of Eco-Friendly and Disease-Resistant Channel Catfish(Ictalurus punctatus)Harboring the Alligator Cathelicidin Gene via CRISPR/Cas9 Engineering

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Engineering 2024年第8期39卷 273-286页

作者： Jinhai Wang Baofeng Su De Xing Timothy J.Bruce Shangjia Li Logan Bern Mei Shang Andrew Johnson Rhoda Mae C.Simora Michael Coogan Darshika u.Hettiarachchi Wenwen Wang Tasnuba Hasin Jacob Al-Armanazi Cuiyu Lu Rex A.Dunham School of Fisheries Aquacultureand Aquatic SciencesAuburn UniversityAuburnAL 36849USA

As a precise and versatile tool for genome manipulation,the clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)platform holds promise for modifying fish traits of *** the aim of reducing transgene introgression and controlling reproduction,upscaled disease resistance and reproductive intervention in catfish species have been studied to lower the potential environmental risks of the introgression of escapees as transgenic *** advantage of the CRISPR/Cas9-mediated system,we succeeded in integrating the cathelicidin gene(As-Cath)from an alligator(Alligator sinensis)into the target luteinizing hormone(lh)locus of channel catfish(Ictalurus punctatus)using two delivery systems assisted by double-stranded DNA(dsDNA)and single-stranded oligodeoxynucleotides(ssODNs),*** this study,high knock in(KI)efficiency(22.38%,64/286)but low ontarget events was achieved using the ssODN strategy,whereas adopting a dsDNA as the donor template led to an efficient on-target KI(10.80%,23/213).The on-target KI of As-Cath was instrumental in establishing the lh knockout(LH^(–)_As-Cath^(+))catfish line,which displayed heightened disease resistance and reduced fecundity compared with the wild-type(WT)sibling ***,administration of human chorionic gonadotropin(HCG)and luteinizing hormone-releasing hormone analogue(LHRHa)can restore the reproduction of the transgenic fish ***,we replaced the lh gene with an alligator cathelicidin transgene and then administered hormone therapy to move towards complete reproductive control of diseaseresistant transgenic catfish in an environmentally responsible *** strategy not only effectively improves consumer-valued traits but also guards against unwanted introgression,providing a breakthrough in aquaculture genetics to confine fish reproduction and prevent the establishment of transgenic or domestic genotypes in the natural environment.

关键词： Genome editing ssODN dsDNA Antimicrobial peptide Reproductive confinement Aquaculture

Conserved Quantities in f(R) Gravity via Noether Symmetry

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Chinese Physics Letters 2012年第8期29卷 33-37页

作者： M.Farasat shamir Adil Jhangeer Akhlaq Ahmad Bhatti Department of Sciences&Humanities National University of Computer&Emerging SciencesLahore CampusPakistan

We investigate f(R)gravity using the Noether symmetry *** this purpose,we consider Friedmann Robertson–Walker(FRW)universe and spherically symmetric *** Noether symmetry generators are evaluated for some specific choice of f(R)models in the presence of the gauge ***,we calculate the corresponding conserved quantities in each ***,the importance and stability criteria of these models are discussed.

关键词： symmetry Noether gauge

Wormhole solutions and energy conditions in f(R,G)gravity

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Communications in Theoretical Physics 2021年第11期73卷 131-141页

作者： M Farasat shamir G Mustafa Saad Waseem Mushtaq Ahmad National university of Computer and Emerging Sciences Lahore CampusPakistan Department of Mathematics Shanghai UniversityShanghai200444China National university of Computer and Emerging Sciences Chiniot-Faisalabad CampusPakistan

In this manuscript,the traversable wormhole solutions have been explored in modified f(R,G)gravity by taking into consideration the model f(R,G)=R+rG2,where R is the Ricci curvature scalar and G is the Gauss–Bonnet *** acceptable form of the redshift function has been incorporated which is a non-constant in nature along with the implementation of those already defined in literature,the two shape functions namely b(r)=r/exp(r-r0)and b(r)=r0log(r+1)/log(r0+1).It is shown by studying the energy condition and through the graphical analysis that the null energy bounds for the effective energy-momentum tensor are generally violated for the presence of the ordinary matter in modified f(R,G)*** conditions associated with the matter content threading the wormhole geometries are evaluated and in general are found to favor the null energy conditions in the vicinity of the wormhole throat,the existence of the nonexotic wormhole geometries threaded by the matter has been confirmed under this gravity.

关键词： f(R,G)gravity energy conditions wormholes shape function

Bacterial viability assessment by flow cytometry analysis in soil

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Frontiers in Biology 2009年第4期4卷 424-435页

作者： Ido shamir Eran ZAHAVY Yosef STEINBERGER The Mina and Everard Goodman Faculty of Life Sciences Bar-Ilan UniversityRamat-Gan 52900Israel Israel Institute for Biological Research P.O.Box 19Ness-Ziona 74100Israel

Soil microhabitats and their heterogeneity are often considered to be among the most important factors affecting soil biotic *** microbial commu-nity has become one of the most important links in soil nutrient cycles and trophic components due to its role in biological processes,spatial and temporal dynamics,and physiological ***-soil desert systems are characterized by fast water infiltration during the rainy season,high salinity,and low moisture availability in the upper soil *** have developed different ecophy-siological adaptations in order to cope with this harsh *** Tamarix aphylla is known to be one of the most commonly adapted plants,exhibiting a mechan-ism for secretion of excess salts as aggregates through its *** leaves aggregate beneath the plant,creating'islands of salinity'.Soil biotic components are,therefore,exposed to extreme abiotic stress conditions in this *** goal of this study was to examine the effect of *** on the live/dead bacterial population ratio on a spatial and temporal *** results emphasize the effect of abiotic factors,which changed on temporal as well as spatial scales,and also on the size of the active soil bacterial community,which fluctuated between 1.44%and 25.4%in summer and winter,*** results of this study elucidate the importance of moisture availability and the'island-of-salinity'effect on the active microbial community in a sandy desert system.

关键词： desert islands of salinity live/dead bacteria ratio microbial community soil flow cytometry

Human leukocyte antigen compatibility and incidence of donorspecific antibodies in pediatric liver transplant recipients

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World Journal of Gastroenterology 2024年第33期30卷 3837-3845页

作者： Melina u Melere Flavia H Feier Jorge Neumann Antônio N Kalil Juliana de M Montagner Luiza S Nader Carolina S da Silva Marco Aurélio F Junior Gabriela P Coral Guilherme P Bobsin Cristina T Ferreira Department of Hepatology and Liver Transplantation Santa Casa de Porto AlegrePorto Alegre 90050170Rio Grande do SulBrazil Department of Hepato-biliary-pancreatic Surgery and Liver Transplantation Irmandade Santa Casa de Misericórdia de Porto AlegrePorto Alegre 90020-090Rio Grande do SulBrazil Postgraduation Program in Medicine:Hepatology Federal University of Health Sciences of Porto AlegrePorto Alegre 90050-170Rio Grande do SulBrazil Laboratory of Transplantation Immunology Irmandade Santa Casa de Misericórdia de Porto AlegrePorto Alegre 90020-090Rio Grande do SulBrazil

BACKGROuND Antibody-mediated rejection following liver transplantation(LT)has been increasingly recognized,particularly with respect to the emergence of de novo donor-specific antibodies(DSAs)and their impact on graft *** substantial evidence for adult populations exists,research focusing on pediatric LT outcomes remains *** To investigate the prevalence of human leukocyte antigen(HLA)mismatches and DSA and evaluate their association with rejection episodes after pediatric *** A cohort of pediatric LT recipients underwent HLA testing at Santa Casa de Porto Alegre,Brazil,between December 2013 and December *** patients who survived for>30 days after LT with at least one DSA analysis were *** classes I and II and cross-matches were *** presence of de novo DSA(dnDSA)was evaluated at least 3 months after LT using the Luminex®single antigen bead method,with a positive reaction threshold set at 1000 *** episodes were confirmed by liver *** Overall,67 transplanted children were analyzed;61 received grafts from living donors,85%of whom were related to ***-transplant DSA(class I or II)was detected in 28.3%of patients,and dnDSA was detected in 48.4%.The median time to DSA detection after LT was 19.7[interquartile range(IQR):4.3-35.6]*** rejection occurred in 13 patients at follow-up,with C4d positivity observed in 5/13 Liver *** median time to rejection was 7.8(IQR:5.7-12.8)*** presence of dnDSA was significantly associated with rejection(36%vs 3%,Purvival rates at 12 and 24 months were 76%vs 100%and 58%vs 95%for patients with dnDSA anti-DQ vs those without,*** Our findings highlight the importance of incorporating DSA assessment into pre-and post-transplantation protocols for pediatric LT *** implications may include immunosuppression minimization strategies based on this analysis in pediatric LT recip

关键词： Human leukocyte antigens Donor-specific antibodies Liver transplantation Pediatric Rejection