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Current Medical Science 2020年第4期40卷 614-617页

作者： Ze-gang WU Hong-yun ZHENG Jian GU Feng LI Rui-long LV ya-yun deng Wan-zhou XU Yong-qing TONG Department of Clinical Laboratory Rentnin Hospital of Wuhan UniversityWuhan 430060China

Summary:The novel coronavirus SARS-CoV-2 caused an outbreak of pneumonia in Wuhan,Hubei province of China in January *** study aims to investigate the effects of different temperature and time durations of virus inactivation on the results of PCR testing for *** patients at the Renmin Hospital of Wuhan University suspected of being infected with SARS-CoV-2 were selected on February 13,2020 and throat swabs were *** swabs were stored at room tempcrature(20-25℃),then divided into aliquots and subjected to different temperature for different periods in order to inactivate the viruses(56℃for 30,45,60 min;65,70,80℃for 10,15,20 min).Control aliquots were stored at room temperature for 60 *** all aliquots were tested in a real-time fluorescence PCR using primers against *** of inactivation temperature and time,7 of 12 cases(58.3%)tested were positive for SARS-CoV-2 by PCR,and cycle threshold values were *** results suggest that virus inactivation parameters exert minimal infuence on PCR test *** at 65℃for 10 min may be sufficient to ensure safe,reliable testing.

关键词： SARS-CoV-2 COVID-19 throat swabs real-time fluorescence PCR

The synthetic gauge field and exotic vortex phase with spin-orbital-angular-momentum coupling

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Communications in Theoretical Physics 2024年第8期76卷 52-59页

作者： Yingqi Liu yun Chen Yuangang deng Guangdong Provincial Key Laboratory of Quantum Metrology and Sensing&School of Physics and Astronomy Sun Yat-Sen University(Zhuhai Campus)Zhuhai 519082China

Ultracold atoms endowed with tunable spin-orbital-angular-momentum coupling(SOAMC)represent a promising avenue for delving into exotic quantum phenomena. Building on recent experimental advancements, we propose the generation of synthetic gauge fields, and by including exotic vortex phases within spinor Bose-Einstein condensates, employing a combination of a running wave and Laguerre-Gaussian laser fields. We investigate the ground-state characteristics of the SOAMC condensate, revealing the emergence of exotic vortex states with controllable orbital angular momenta. It is shown that the interplay of the SOAMC and conventional spin-linear-momentum coupling induced by the running wave beam leads to the formation of a vortex state exhibiting a phase stripe hosting single multiply quantized singularity. The phase of the ground state will undergo the phase transition corresponding to the breaking of rotational symmetry while preserving the mirror symmetry. Importantly, the observed density distribution of the ground-state wavefunction, exhibiting broken rotational symmetry, can be well characterized by the synthetic magnetic field generated through light interaction with the dressed spin state. Our findings pave the way for further exploration into the rotational properties of stable exotic vortices with higher orbital angular momenta against splitting in the presence of synthetic gauge fields in ultracold quantum gases.

关键词： ultracold atoms synthetic gauge fields vortex phases spin-orbital-angularmomentum coupling

Special issue on electrochemical energy storage and conversion

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Frontiers in Energy 2024年第2期18卷 125-127页

作者： yun ZHENG Gaixia ZHANG Sixu deng Jiujun ZHANG Institute of New Energy Materials and Engineering School of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China Department of Electrical Engineering École de Technologie Supérieure(ÉTS)Universitédu QuébecMontréalH3C 1K3Canada Department of Chemical and Materials Engineering Concordia UniversityMontrealQC H3G 1M8Canada

The escalating global consumption of fossil fuels has significantly elevated the levels of CO_(2)in the atmosphere,leading to an undesirable global energy crisis and environmental *** deployment of renewable energy resources is crucial to mitigate these *** recent years,there has been noteworthy progress in electrochemical energy storage and conversion techniques and devices,including hydrogen energy and fuel cells,advanced energy storage and power batteries,and CO_(2)electrochemical conversion and utilization.

关键词： electrochemical energy elevated

A unified Minorization-Maximization approach for estimation of general mixture models

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 343-362页

作者： HUANG Xi-fen LIU deng-ge ZHOU yun-peng ZHU Fei School of Mathematics Yunnan Normal UniversityKunming 650092China Department of Statistics and Actuarial Science The University of Hong KongHong KongChina

The mixed distribution model is often used to extract information from heteroge-neous data and perform modeling *** the density function of mixed distribution is complicated or the variable dimension is high,it usually brings challenges to the parameter es-timation of the mixed distribution *** application of MM algorithm can avoid complex expectation calculations,and can also solve the problem of high-dimensional optimization by decomposing the objective *** this paper,MM algorithm is applied to the parameter estimation problem of mixed distribution *** method of assembly and decomposition is used to construct the substitute function with separable parameters,which avoids the problems of complex expectation calculations and the inversion of high-dimensional matrices.

关键词： MM algorithm mixed distribution model parameter estimation assembly decomposition tech-nology parameter separation

Theoretical study on the effect of H_(2)O on the formation mechanism of NO_(x) precursors during indole pyrolysis

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Frontiers of Chemical Science and Engineering 2024年第6期18卷 99-112页

作者： Ziqi Wang Jun Shen Xuesong Liu Sha Wang Shengxiang deng Hai Zhang yun Guo School of Mechanical and Automotive Engineering Shanghai University of Engineering ScienceShanghai 201620China School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

The incineration technology of kitchen waste is one of the effective technologies to achieve the resource utilization of municipal solid *** is an important stage of *** is a rich initial product in the pyrolysis process of kitchen waste,and the presence of H_(2)O has a significant impact on the decomposition of indole to form NO_(x) ***,this study uses density functional theory method to study the effect of H_(2)O on the thermal decomposition of indole to produce NH_(3),HNCO,and *** H_(2)O participates in the reaction,it can provide oxidative groups to generate a new product HNCO,which is different from the previous findings by indole pyrolysis without the presence of H_(2)***,this study theoretically proves that NH_(3) is easier to form than *** is consistent with the phenomenon that NH_(3) release is higher than HCN release in pyrolysis *** addition,compared with the individual pyrolysis of indole,the participation of H_(2)O reduces the energy barriers for the formation of NH_(3) and HCN during indole pyrolysis,thereby promoting the formation of NH_(3) and HCN.

关键词： indole pyrolysis H_(2)O NO_(x)precursors DFT

Laparoscopic vs open surgery for gastric cancer: Assessing time, recovery, complications, and markers

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World Journal of Gastrointestinal Surgery 2024年第1期16卷 40-48页

作者： yun-yao Lu yun-Xiao Li Meng He ya-Li Wang Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment Chongqing University Cancer HospitalChongqing 400030China

BACKGROUND Gastric cancer(GC)is one of the most common cancers *** and mortality have increased in recent years,making it an urgent issue to ***-paroscopic radical surgery(LRS)is a crucial method for treating patients with GC;However,its influence on tumor markers is still under *** data of 194 patients treated at Chongqing University Cancer Hospital bet-ween January 2018 and January 2019 were retrospectively *** who underwent traditional open surgery and LRS were assigned to the control(n=90)and observation groups(n=104),*** sample t-tests andχ2 tests were used to compare the two groups based on clinical efficacy,changes in tumor marker levels after treatment,clinical data,and the incidence of posto-perative *** investigate the association between tumor marker levels and clinical efficacy in patients with GC,three-year recurrence rates in the two groups were *** Patients in the observation group had a shorter duration of operation,less in-traoperative blood loss,an earlier postoperative eating time,and a shorter hospital stay than those in the control group(P0.05).After treatment,the overall response rate in the control group was significantly lower than that in the observation group(P=0.001).Furthermore,after treatment,the levels of carbohydrate antigen 19-9,cancer antigen 72-4,carcinoembryonic antigen,and cancer antigen 125 decreased *** observation group also exhibited a significantly lower incidence rate of postoperative complications compared to the control group(P0.05).CONCLUSION LRS effectively treats early gastric cancer by reducing intraoperative bleeding,length of hospital stays,and postoperative complications.I

关键词： Laparoscopic radical surgery Gastric cancer Serum tumor markers Prognosis Recurrence Intraoperative bleeding

Triggering triplet excitons of carbon nanodots through nanospace domain confinement for multicolor phosphorescence in aqueous solution

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Nano Research 2024年第7期17卷 6534-6543页

作者： ya-Chuan Liang Qing Cao Yuan deng Yong Wang Kai-Kai Liu Chong-Xin Shan School of Electronics and Information Zhengzhou University of Light IndustryZhengzhou 450002China Henan Key Laboratory of Diamond Optoelectronic Material and Devices Key Laboratory of Material PhysicsMinistry of EducationSchool of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450001China Academy for Quantum Science and Technology Zhengzhou University of Light IndustryZhengzhou 450002China Institute of Quantum Materials and Physics Henan Academy of SciencesZhengzhou 450046China

Easy non-radiative decay property of long-lived triplet excitons in aqueous solution obstructs their applications in aquatic *** reported phosphorescence phenomena in aqueous solution have excited researchers enormously but achieving full-color water-soluble phosphorescent carbon nanodots(CNDs)is still a challenging ***,full-color phosphorescence of water-soluble CNDs has been demonstrated by triggering their triplet excitons through nanospace domain confinement,and Förster energy resonance transfer is used for further tuning phosphorescence *** phosphorescence spans across most of the visible spectrum,ranging from 400 to 700 *** an aqueous solution,the CNDs exhibits blue,green,and red phosphorescence,lasting for approximately 6,10,and 7 s,***,the phosphorescence quantum yields are 11.85%,8.6%and 3.56%,making them readily discernible to the naked eyes and laying a solid foundation for practical ***,phosphorescence flexible optical display and bioimaging have been demonstrated by using the multicolor CNDs-based nanomaterials,showing distinct superiority for accuracy and complete display and imaging in complex emission background.

关键词： carbon nanodots triplet excitons multicolor aqueous solution

Analytical solution for the effective elastic properties of rocks with the tilted penny-shaped cracks in the transversely isotropic background

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Petroleum Science 2024年第1期21卷 221-243页

作者： Zheng-Qian Ma Xing-yao Yin Zhao-yun Zong Yuan-Yuan Tan ya-Ming yang National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina School of Geosciences China University of Petroleum(East China)Qingdao 266580ShandongChina Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao266200ShandongChina

Seismic prediction of cracks is of great significance in many disciplines,for which the rock physics model is ***,up to now,multitudinous analytical models focus primarily on the cracked rock with the isotropic background,while the explicit model for the cracked rock with the anisotropic background is rarely investigated in spite of such case being often encountered in the ***,we first studied dependences of the crack opening displacement tensors on the crack dip angle in the coordinate systems formed by symmetry planes of the crack and the background anisotropy,respectively,by forty groups of numerical *** on the conclusion from the experiments,the analytical solution was derived for the effective elastic properties of the rock with the inclined penny-shaped cracks in the transversely isotropic ***,we comprehensively analyzed,according to the developed model,effects of the crack dip angle,background anisotropy,filling fluid and crack density on the effective elastic properties of the cracked *** analysis results indicate that the dip angle and background anisotropy can significantly either enhance or weaken the anisotropy degrees of the P-and SH-wave velocities,whereas they have relatively small effects on the SV-wave velocity ***,the filling fluid can increase the stiffness coefficients related to the compressional modulus by reducing crack compliance parameters,while its effects on shear coefficients depend on the crack dip *** increasing crack density reduces velocities of the dry rock,and decreasing rates of the velocities are affected by the crack dip *** comparing with exact numerical results and experimental data,it was demonstrated that the proposed model can achieve high-precision estimations of stiffness ***,the assumption of the weakly anisotropic background results in the consistency between the proposed model and Hudson's published theory for the or

关键词： Effective elastic property Tilted crack Transverse isotropy Analytical solution Crack opening displacement

Impact of High Sodium Diet on Neovascularization and Osseointegration around Titanium Implant:An in Vivo and in Vitro Study

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Biomedical and Environmental Sciences 2024年第7期37卷 739-753页

作者： Keyuan Xu Xiaoting Tang yun Xiang Yiding Shen Zhennan deng Pingping Ma Xinkun Shen Department of Orthopaedics The Third Affiliated Hospital of Wenzhou Medical University(Ruian People’s Hospital)Wenzhou 325016ZhejiangChina School and Hospital of Stomatology Wenzhou Medical UniversityWenzhou 325027ZhejiangChina

Objective A high sodium(HS)diet is believed to affect bone metabolism *** its impact on osseointegration of titanium(Ti)implants holds significant implications for postoperative dietary management of implanted *** This investigation probed the impact of sodium ions(Na^(+))on neovascularization and osteogenesis around Ti implants in vivo,utilizing micro-computed tomography,hematoxylin and eosin staining,and immunohistochemical ***,in vitro experiments assessed the effects of varied Na^(+)concentrations and exposure durations on human umbilical vein endothelial cells(HUVECs)and MC3T3-E1 *** In vivo,increased dietary sodium(0.8%-6.0%)led to a substantial decline in CD34 positive HUVECs and new bone formation around Ti implants,alongside an increase in inflammatory *** vitro,an increase in Na^(+)concentration(140-150 mmol/L)adversely affected the proliferation,angiogenesis,and migration of HUVECs,especially with prolonged *** MC3T3-E1 cells initially exhibited less susceptibility to high Na^(+)concentrations compared to HUVECs during short-term exposure,prolonged exposure to a HS environment progressively diminished their proliferation,differentiation,and osteogenic *** These findings suggest that HS diet had a negative effect on the early osseointegration of Ti implants by interfering with the process of postoperative vascularized bone regeneration.

关键词： High-sodium Implants Vascularization Osseointegration

Overstory functional groups indicate the legacy of land use in a secondary tropical forest in southwestern China

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JOURNAL OF FORESTRY RESEARCH 2024年第1期35卷 1-15页

作者： deng, yun Zhang, Wenfu Cao, Min Dong, Jinlong Chen, Hui deng, Xiaobao Liu, Jiajia Song, Xiaoyang Xia, Shangwen Sha, Liqing Yuan, Shengdong Lin, Luxiang Chinese Acad Sci CAS Key Lab Trop Forest Ecol Xishuangbanna Trop Bot Garden Mengla 666303 Peoples R China Chinese Acad Sci Ctr Plant Ecol Core Bot Gardens Mengla 666303 Peoples R China Chinese Acad Sci Natl Forest Ecosyst Res Stn Xishuangbanna Xishuangbanna Trop Bot Garden Mengla 666303 Peoples R China Univ Chinese Acad Sci Dept Life Sci Beijing 100049 Peoples R China Fudan Univ Dept Life Sci Shanghai 570228 Peoples R China

Anthropogenic disturbances are widespread in tropical forests and influence the species composition in the overstory. However, the impacts of historical disturbance on tropical forest overstory recovery are unclear due to a lack of disturbance data, and previous studies have focused on understory species. In this study, the purpose was to determine the influence of historical disturbance on the diversity, composition and regeneration of overstory species in present forests. In the 20-ha Xishuangbanna tropical seasonal rainforest dynamics plot in southwestern China, the historical disturbance boundaries were delineated based on panchromatic photographs from 1965. Factors that drove species clustering in the overstory layer (DBH >= 40 cm) were analyzed and the abundance, richness and composition of these species were compared among different tree groups based on multiple regression tree analysis. The coefficient of variation of the brightness value in historical panchromatic photographs from 1965 was the primary driver of species clustering in the overstory layer. The abundance and richness of overstory species throughout the regeneration process were similar, but species composition was always different. Although the proportion of large-seeded and vigorous-sprouting species showed no significant difference between disturbed and undisturbed forests in the treelet layer (DBH < 20 cm), the difference became significant when DBH increased. The findings highlight that historical disturbances have strong legacy effects on functional group composition in the overstory and the recovery of overstory species was multidimensional. Functional group composition can better indicate the dynamics of overstory species replacement during secondary succession.

关键词： Historical disturbance Legacy effects Secondary forests Overstory species Functional groups RAIN-FOREST MULTIVARIATE ANALYSES SEED SIZE VEGETATION TREES XISHUANGBANNA REGENERATION DISTURBANCE RECOVERY yunNAN