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Individualization of Head Related Impulse Responses Using Division Analysis 被引量:1
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作者 Wei Chen Ruimin Hu +2 位作者 Xiaochen Wang Cheng Yang Lian Meng 《China Communications》 SCIE CSCD 2018年第5期92-103,共12页
For Virtual Reality(VR) to be truly immersive, it needs convincing sound to match. Due to the diversity of individual's anthropometric measurements, the individualized customization technology is needed to get con... For Virtual Reality(VR) to be truly immersive, it needs convincing sound to match. Due to the diversity of individual's anthropometric measurements, the individualized customization technology is needed to get convincing sound. In this paper, we proposed a simple and effective method for modeling relationships between anthropometric measurements and Head-related Impulse Response(HRIR). Considering the relationship between anthropometric measurements and different HRIR parts is complicated, we divided the HRIRs into small segments and carried out regression analysis between anthropometric measurements and each segment to establish relationship model. The results of objective simulation and subjective test indicate that the model can generate individualize HRIRs from a series of anthropometric measurements. With the individualized HRIRs, we can get more accurate acoustic localization sense than using non-individualized HRIRs. 展开更多
关键词 HRIR individualization Division analysis
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Social Sensors (S^2ensors): A Kind of Hardware-Software-Integrated Mediators for Social Manufacturing Systems Under Mass Individualization 被引量:2
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作者 Kai Ding Ping-Yu Jiang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第5期1150-1161,共12页
Currently, little work has been devoted to the mediators and tools for multi-role production interactions in the mass individualization environment. This paper proposes a kind of hardware-software-integrated mediators... Currently, little work has been devoted to the mediators and tools for multi-role production interactions in the mass individualization environment. This paper proposes a kind of hardware-software-integrated mediators called social sensors (S2ensors) to facilitate the production interactions among customers, manufacturers, and other stakeholders in the social manufacturing systems (SMS). The concept, classification, operational logics, and for- malization of S2ensors are clarified. S2ensors collect sub- jective data from physical sensors and objective data from sensory input in mobile Apps, merge them into meaningful information for decision-making, and finally feed the decisions back for reaction and execution. Then, an S2en- sors-Cloud platform is discussed to integrate different S2- ensors to work for SMSs in an autonomous way. A demonstrative case is studied by developing a prototype system and the results show that S2ensors and S2ensors- Cloud platform can assist multi-role stakeholders interact and collaborate for the production tasks. It reveals the mediator-enabled mechanisms and methods for production interactions among stakeholders in SMS. 展开更多
关键词 Social sensors Social manufacturing system Individualized production Production interaction
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Dose-individualization Efficiently Maintains Sufficient Exposure to Methotrexate without Additional Toxicity in High-dose Methotrexate Regimens for Pediatric Acute Lymphoblastic Leukemia
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作者 Ya-qing SHEN Zhu-jun WANG +5 位作者 Xiao-yan WU Kun LI Zhong-jian WANG Wen-fu XU Fen ZHOU Run-ming JIN 《Current Medical Science》 SCIE CAS 2022年第4期769-777,共9页
Objective:Methotrexate(MTX)can be safely administered to most patients but may cause severe toxicity in others.This study aimed to summarize the characteristics of high-dose methotrexate(HD-MTX)chemotherapy and to eva... Objective:Methotrexate(MTX)can be safely administered to most patients but may cause severe toxicity in others.This study aimed to summarize the characteristics of high-dose methotrexate(HD-MTX)chemotherapy and to evaluate whether the modified dose-adjustment program was able to improve the maintenance of sufficient MTX exposure levels while minimizing toxicities.Methods:We evaluated 1172 cycles of high-dose MTX chemotherapy from 294 patients who were treated according to the CCCG-ALL-2015 protocol(clinical trial number:ChiCTR-IPR-14005706)and analyzed the data of actual MTX dosage,MTX concentration,toxicity,and prognosis.We compared data between the dose-adjustment Program 1(fixed 20%reduction in dose)and the dose-adjustment Program 2(dose-individualization based on reassessment of the creatine clearance rate and the MTX concentration-monitoring point at 16 h),which were applied if the MTX clearance was delayed in the previous cycle.Results:The patients who used Program 2 had higher actual MTX infusion doses and infusion rates and were able to better maintain the MTX concentration at 44 h at the established target value than those on Program 1(P<0.001).No significant differences in toxicities were found between these two programs except that abnormal serum potassium levels and prolonged myelosuppression in intermediate-risk/high-risk patients were more frequently observed in patients using Program 2(P<0.001).No significant correlations were observed between the MTX dose,dose-adjustment programs,or MTX concentrations and relapse-free survival.Conclusion:Adjusting the MTX dose using Program 2 is more efficient for maintaining sufficient MTX exposure without significantly increasing the toxicity. 展开更多
关键词 METHOTREXATE high-dose methotrexate individualizing methotrexate dose TOXICITY acute lymphoblastic leukemia prognosis
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Adenine nucleotide translocase 2(Ant2)is required for individualization of spermatogenesis of Drosophila melanogaster
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作者 Zhen He Yang Fang +6 位作者 Fengchao Zhang Yang Liu Xinkai Cheng Jiajia Wang Dechen Li Dengsong Chen Fan Wu 《Insect Science》 SCIE CAS CSCD 2024年第4期1055-1072,共18页
Successful completion of spermatogenesis is crucial for the perpetuation of the species.In Drosophila,spermatid individualization,a process involving changes in mitochondrial structure and function is critical to prod... Successful completion of spermatogenesis is crucial for the perpetuation of the species.In Drosophila,spermatid individualization,a process involving changes in mitochondrial structure and function is critical to produce functional mature sperm.Ant2,encoding a mitochondrial adenine nucleotide translocase,is highly expressed in male testes and plays a role in energy metabolism in the mitochondria.However,its molecular function remains unclear.Here,we identified an important role of Ant2 in spermatid individualization.In Ant2 knockdown testes,spermatid individualization complexes composed of F-actin cones exhibited a diffuse distribution,and mature sperms were absent in the seminal vesicle,thus leading to male sterility.The most striking effects in Ant2-knockdown spermatids were decrease in tubulin polyglycylation and disruption of proper mitochondria derivatives function.Excessive apoptotic cells were also observed in Ant2-knockdown testes.To further investigate the phenotype of Ant2 knockdown in testes at the molecular level,complementary transcriptome and proteome analyses were performed.At the mRNA level,868 differentially expressed genes were identified,of which 229 genes were upregulated and 639 were downregulated induced via Ant2 knockdown.iTRAQ-labeling proteome analysis revealed 350 differentially expressed proteins,of which 117 proteins were upregulated and 233 were downregulated.The expression of glutathione transferase(GstD5,GstE5,GstE8,and GstD3),proteins involved in reproduction were significantly regulated at both the mRNA and protein levels.These results indicate that Ant2 is crucial for spermatid maturation by affecting mitochondrial morphogenesis. 展开更多
关键词 adenine nucleotide translocase Drosophila melanogaster individualization complexes MITOCHONDRIA SPERMATOGENESIS tubulin polyglycylation
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First Light Curve Analysis of NSVS 8294044,V1023 Her,and V1397 Her Contact Binary Systems 被引量:1
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作者 Atila Poro Sabrina Baudart +7 位作者 Mahshid Nourmohammad Zahra Sabaghpour Arani Fatemeh Farhadi Selda Ranjbar Salehian Ahmad Sarostad Saeideh Ranjbaryan Iri Olya Maryam Hadizadeh AmirHossein Khodaei 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第5期1-12,共12页
The first photometric light curve investigation of the NSVS 8294044,V1023 Her,and V1397 Her binary systems is presented.We used ground-based observations for the NSVS 8294044 system and Transiting Exoplanet Survey Sat... The first photometric light curve investigation of the NSVS 8294044,V1023 Her,and V1397 Her binary systems is presented.We used ground-based observations for the NSVS 8294044 system and Transiting Exoplanet Survey Satellite data for V1023 Her and V1397 Her.The primary and secondary times of minima were extracted from al the data,and,by collecting the literature,a new ephemeris was computed for each system.Linear fits for the O-C diagrams were conducted using the Markov Chain Monte Carlo (MCMC) method.Light curve solutions were performed using the PHysics Of Eclipsing BinariEs Python code and the MCMC approach.The systems were found to be contact binary stars based on the fillout factor and mass ratio.V1023 Her showed the O’Connell effect and a cold starspot on the secondary component was required for the light curve solution.The absolute parameters of the system were estimated based on an empirical relationship between orbital period and mass.We presented a new T–M equation based on a sample of 428 contact binary systems and found that our three target systems were in good agreement with the fit.The positions of the systems were also depicted on the M–L,M–R,q–L_(ratio),and M_(tot)–J_(0)diagrams in the logarithmic scales. 展开更多
关键词 (stars:)binaries eclipsing-techniques photometric-stars individual(NSVS 8294044)
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Value of multiple models of diffusion-weighted imaging to predict hepatic lymph node metastases in colorectal liver metastases patients 被引量:1
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作者 Hai-Bin Zhu Bo Zhao +3 位作者 Xiao-Ting Li Xiao-Yan Zhang Qian Yao Ying-Shi Sun 《World Journal of Gastroenterology》 SCIE CAS 2024年第4期308-317,共10页
BACKGROUND About 10%-31% of colorectal liver metastases(CRLM)patients would concomitantly show hepatic lymph node metastases(LNM),which was considered as sign of poor biological behavior and a relative contraindicatio... BACKGROUND About 10%-31% of colorectal liver metastases(CRLM)patients would concomitantly show hepatic lymph node metastases(LNM),which was considered as sign of poor biological behavior and a relative contraindication for liver resection.Up to now,there’s still lack of reliable preoperative methods to assess the status of hepatic lymph nodes in patients with CRLM,except for pathology examination of lymph node after resection.AIM To compare the ability of mono-exponential,bi-exponential,and stretchedexponential diffusion-weighted imaging(DWI)models in distinguishing between benign and malignant hepatic lymph nodes in patients with CRLM who received neoadjuvant chemotherapy prior to surgery.METHODS In this retrospective study,97 CRLM patients with pathologically confirmed hepatic lymph node status underwent magnetic resonance imaging,including DWI with ten b values before and after chemotherapy.Various parameters,such as the apparent diffusion coefficient from the mono-exponential model,and the true diffusion coefficient,the pseudo-diffusion coefficient,and the perfusion fraction derived from the intravoxel incoherent motion model,along with distributed diffusion coefficient(DDC)andαfrom the stretched-exponential model(SEM),were measured.The parameters before and after chemotherapy were compared between positive and negative hepatic lymph node groups.A nomogram was constructed to predict the hepatic lymph node status.The reliability and agreement of the measurements were assessed using the coefficient of variation and intraclass correlation coefficient.RESULTS Multivariate analysis revealed that the pre-treatment DDC value and the short diameter of the largest lymph node after treatment were independent predictors of metastatic hepatic lymph nodes.A nomogram combining these two factors demonstrated excellent performance in distinguishing between benign and malignant lymph nodes in CRLM patients,with an area under the curve of 0.873.Furthermore,parameters from SEM showed substantial repeatability.CONCLUSION The developed nomogram,incorporating the pre-treatment DDC and the short axis of the largest lymph node,can be used to predict the presence of hepatic LNM in CRLM patients undergoing chemotherapy before surgery.This nomogram was proven to be more valuable,exhibiting superior diagnostic performance compared to quantitative parameters derived from multiple b values of DWI.The nomogram can serve as a preoperative assessment tool for determining the status of hepatic lymph nodes and aiding in the decision-making process for surgical treatment in CRLM patients. 展开更多
关键词 Colorectal cancer Individualized treatment Diffusion magnetic resonance imaging Intravoxel incoherent motion LIVER
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Individualization,Collaboration,Modularization,and Hypertextualization in College English Teaching Reform 被引量:1
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作者 胡壮麟 《中国外语》 2004年第1期49-55,75,共8页
The recently issued "College English Curriculum Requirements"is a win-win game of a democratic process undergoing many rounds of discussions between government administrators and College English teachers in ... The recently issued "College English Curriculum Requirements"is a win-win game of a democratic process undergoing many rounds of discussions between government administrators and College English teachers in China. The theme of the paper is to discuss that the new "Requirements" reflects the findings and insights gained from those fields such as philosophy, linguistics, literary criticism, psychology, and pedagogy, which can be described in terms of individualization, collaboration, modularization, and hypertextualization. It is held that the "Requirements" is a milestone of China's College English teaching reform, and is sure to further push forward foreign language teaching reform in general. 展开更多
关键词 individualization COLLABORATION MODULARIZATION hypertextualization COLLEGE ENGLISH TEACHING
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Gait Recognition Under Different Clothing Conditions Via Deterministic Learning
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作者 Muqing Deng Cong Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1530-1532,共3页
Dear Editor,This letter deals with the robustness problem of gait recognition method against maximum number of clothing conditions.By selecting four kinds of time-varying silhouette features,gait dynamics underlying d... Dear Editor,This letter deals with the robustness problem of gait recognition method against maximum number of clothing conditions.By selecting four kinds of time-varying silhouette features,gait dynamics underlying different individuals’gait features is effectively modeled by radial basis function(RBF)neural networks through deterministic learning.This kind of dynamics information has little sensitivity to the variance between gait patterns under different clothing conditions.In order to eliminate the effect of clothing differences,the training patterns under different clothing conditions further constitute a uniform training dataset,containing all kinds of gait dynamics under different clothing conditions.A rapid recognition scheme is presented on published gait databases.Extensive experiments demonstrate the efficacy of the proposed method. 展开更多
关键词 NETWORKS NEURAL INDIVIDUAL
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New HⅠObservations Toward the NGC 5055 Galaxy Group with FAST
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作者 Xiao-Lan Liu Ming Zhu +5 位作者 Jin-Long Xu Peng Jiang Chuan-Peng Zhang Nai-Ping Yu Jun-Jie Wang Yan-Bin Yang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第7期249-256,共8页
We report a new high-sensitivity HⅠmapping observation of the NGC 5055 galaxy group over an area of 1°.5×0°.75 with the Five-hundred-meter Aperture Spherical radio Telescope(FAST).Our observation revea... We report a new high-sensitivity HⅠmapping observation of the NGC 5055 galaxy group over an area of 1°.5×0°.75 with the Five-hundred-meter Aperture Spherical radio Telescope(FAST).Our observation reveals that the warped HⅠdisk of NGC 5055 is more extended than what was previously observed by WSRT,out to239(61.7 kpc).The total HⅠmass of NGC 5055 is determined to be~1.1×10^(10)M_Θ.We identified three HⅠclouds with HⅠmasses of the order of~10^(7)M_Θat the southeastern edge of the HⅠdisk,as well as a candidate high-velocity cloud with an HⅠmass of(1.2±0.5)×10^(6)M_Θto the north of NGC 5055.The HⅠcontent of UGCA337 is robustly detected for the first time by the FAST observations.It has a narrow HⅠlinewidth of W_(50)=17.4±3.8 km s^(-1)with a total HⅠmass of(3.5±0.3)×10^(6)M_Θ.Comparing the gas content and g-r color of UGCA 337 with typical low-mass dwarf galaxies,UGCA 337 appears relatively gas-poor despite its blue color.This suggests that UGCA 337 may have undergone gas stripping in the past.We also analyzed the possible origin of the diffuse HⅠclouds located at the outskirts of NGC 5055,and speculate that they might be the remnant features of a merger event in the past. 展开更多
关键词 GALAXIES evolution-galaxies structure-galaxies individual(NGC 5055)-galaxies kinematics and dynamics-galaxies INTERACTIONS
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Comparing the efficacy and safety of low,medium,and high dosages of selexipag for treating pulmonary hypertension:A systematic review and meta-analysis
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作者 Shang Wang Yi Yan +8 位作者 Jian Zhang Ping Yuan Ci-Jun Luo Hong-Ling Qiu Hui-Ting Li Jian Xu Lan Wang Tian-Lan Li Rong Jiang 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第1期56-70,共15页
Background:The maintenance dosage of selexipag is categorized as low,medium or high.In order to assess the efficacy and safety of different dosages of selexipag for the risk stratification of pulmonary arterial hypert... Background:The maintenance dosage of selexipag is categorized as low,medium or high.In order to assess the efficacy and safety of different dosages of selexipag for the risk stratification of pulmonary arterial hypertension(PAH),we performed a sys-tematic review and meta-analysis.Methods:Studies assessing PAH risk stratification indices,such as the World Health Organization functional class(WHO-FC),six-minute walk distance(6MWD),N-terminal pro-B-type natriuretic peptide(NT-proBNP)level,right atrial pressure(RAP),cardiac index(CI)and mixed venous oxygen saturation(SvO2),were included.Results:Thirteen studies were included.Selexipag led to improvements in the 6MWD(MD:24.20 m,95%CI:10.74-37.67),NT-proBNP(SMD:-0.41,95%CI:-0.79-0.04),CI(MD:0.47 L/min/m^(2),95%CI:0.17-0.77)and WHO-FC(OR:0.564,95%CI:0.457-0.697).Subgroup analysis demonstrated that all three dosages improved the 6MWD.A moderate dosage led to improvements in the CI(MD:0.30 L/min/m^(2),95%CI:0.15-0.46)and WHO-FC(OR:0.589,95%CI:0.376-0.922).Within 6 months of treatment,only the WHO-FC and CI were significantly improved(OR:0.614,95%CI:0.380-0.993;MD:0.30 L/min/m^(2),95%CI:0.16-0.45,respectively).More than 6 months of treatment significantly improved the 6MWD,WHO-FC and NT-proBNP(MD:40.87 m,95%CI:10.97-70.77;OR:0.557,95%CI:0.440-0.705;SMD:-0.61,95%CI:-1.17-0.05,respectively).Conclusions:Low,medium,and high dosages of selexipag all exhibited good effects.When treatment lasted for more than 6 months,selexipag exerted obvious effects,even in the low-dosage group.This finding is important for guiding individualized treatments. 展开更多
关键词 individualized treatments META-ANALYSIS prostacyclin receptor agonist risk stratification systematic review
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Opinion consensus incorporating higher-order interactions in individual-collective networks
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作者 叶顺 涂俐兰 +2 位作者 王先甲 胡佳 王薏潮 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期105-115,共11页
In the current information society, the dissemination mechanisms and evolution laws of individual or collective opinions and their behaviors are the research hot topics in the field of opinion dynamics. First, in this... In the current information society, the dissemination mechanisms and evolution laws of individual or collective opinions and their behaviors are the research hot topics in the field of opinion dynamics. First, in this paper, a two-layer network consisting of an individual-opinion layer and a collective-opinion layer is constructed, and a dissemination model of opinions incorporating higher-order interactions(i.e. OIHOI dissemination model) is proposed. Furthermore, the dynamic equations of opinion dissemination for both individuals and groups are presented. Using Lyapunov's first method,two equilibrium points, including the negative consensus point and positive consensus point, and the dynamic equations obtained for opinion dissemination, are analyzed theoretically. In addition, for individual opinions and collective opinions,some conditions for reaching negative consensus and positive consensus as well as the theoretical expression for the dissemination threshold are put forward. Numerical simulations are carried to verify the feasibility and effectiveness of the proposed theoretical results, as well as the influence of the intra-structure, inter-connections, and higher-order interactions on the dissemination and evolution of individual opinions. The main results are as follows.(i) When the intra-structure of the collective-opinion layer meets certain characteristics, then a negative or positive consensus is easier to reach for individuals.(ii) Both negative consensus and positive consensus perform best in mixed type of inter-connections in the two-layer network.(iii) Higher-order interactions can quickly eliminate differences in individual opinions, thereby enabling individuals to reach consensus faster. 展开更多
关键词 two-layer social networks individual and collective opinions higher-order interactions CONSENSUS Lyapunov's first method
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Evaluating the relative importance of predictors in Generalized Additive Models using the gam.hp R package
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作者 Jiangshan Lai Jing Tang +2 位作者 Tingyuan Li Aiying Zhang Lingfeng Mao 《Plant Diversity》 SCIE CAS CSCD 2024年第4期542-546,共5页
Generalized Additive Models(GAMs)are widely employed in ecological research,serving as a powerful tool for ecologists to explore complex nonlinear relationships between a response variable and predictors.Nevertheless,... Generalized Additive Models(GAMs)are widely employed in ecological research,serving as a powerful tool for ecologists to explore complex nonlinear relationships between a response variable and predictors.Nevertheless,evaluating the relative importance of predictors with concurvity(analogous to collinearity)on response variables in GAMs remains a challenge.To address this challenge,we developed an R package named gam.hp.gam.hp calculates individual R^(2) values for predictors,based on the concept of'average shared variance',a method previously introduced for multiple regression and canonical analyses.Through these individual R^(2)s,which add up to the overall R^(2),researchers can evaluate the relative importance of each predictor within GAMs.We illustrate the utility of the gam.hp package by evaluating the relative importance of emission sources and meteorological factors in explaining ozone concentration variability in air quality data from London,UK.We believe that the gam.hp package will improve the interpretation of results obtained from GAMs. 展开更多
关键词 Average shared variance Coefficient of determination Commonality analysis GAMs Hierarchical partitioning Individual R^(2)
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Impact of asymptomatic infected individuals on epidemic transmission dynamics in multiplex networks with partial coupling
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作者 Xin Hu Jiaxing Chen Chengyi Xia 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期80-87,共8页
The theory of network science has attracted great interest of many researchers in the realm of biomathematics and public health,and numerous valuable epidemic models have been developed.In previous studies,it is commo... The theory of network science has attracted great interest of many researchers in the realm of biomathematics and public health,and numerous valuable epidemic models have been developed.In previous studies,it is common to set up a one-to-one correspondence between the nodes of a multi-layer network,ignoring the more complex situations in reality.In the present work,we explore this situation by setting up a partially coupled model of a two-layer network and investigating the impact of asymptomatic infected individuals on epidemics.We propose a self-discovery mechanism for asymptomatic infected individuals,taking into account situations such as nucleic acid testing in the community and individuals performing self-antigen testing during the epidemic.Considering these factors together,through the microscopic Markov chain approach(MMCA)and extensive Monte Carlo(MC)numerical simulations,we find that the greater the coupling between the networks,the more information dissemination is facilitated.In order to control the epidemics,more asymptomatic infected individuals should be made aware of their infection.Massive adoption of nucleic acid testing and individual adoption of antigenic self-testing can help to contain epidemic outbreaks.Meanwhile,the epidemic threshold of the proposed model is derived,and then miscellaneous factors affecting the epidemic threshold are also discussed.Current results are conducive to devising the prevention and control policies of pandemics. 展开更多
关键词 asymptomatic infected individuals multi-layer networks partial interdependence
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Study of Type-B QPOs Observed in Black Hole X-Ray Binary Swift J1728.9-3613
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作者 Raj Kumar 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第3期1-9,共9页
We report the detection of type-B quasi-periodic oscillation(QPO)of the black hole X-ray binary Swift J1728.9-3613 observed by NICER during the 2019 outburst.A type-B QPO was observed for the first two days and it dis... We report the detection of type-B quasi-periodic oscillation(QPO)of the black hole X-ray binary Swift J1728.9-3613 observed by NICER during the 2019 outburst.A type-B QPO was observed for the first two days and it disappeared as flux increased,but again appeared at∼7.70 Hz when flux was dramatically decreased.The source was found in the soft intermediate state during these observations.We further studied the energy dependence of the QPO.We found that QPO was observed only for a higher energy range implying that the origin of QPO is possibly due to the corona emitting higher energy photons by the inverse Compton process.The variation of spectral parameters can be explained with the disk truncation model.The fractional rms was found to be monotonically increased with energy.The phase lag spectrum followed the“U-shaped”curve.The rms and phase lag spectrum are modeled and explained with the single-component Comptonization model vkompthdk. 展开更多
关键词 X-rays binaries-accretion-accretion disks-X-rays individual (Swift J1728.9-3613)
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Detection of Increasingγ-Ray Emissions from 4FGL J1718.5+4237 with Fermi-LAT
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作者 Jiao Zheng Pengfei Zhang Li Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第8期169-174,共6页
We report a gradual brighteningγ-ray source,4FGL J1718.5+4237,in 0.1-500.0 GeV,which may be associated with a blazar NVSS J171822+423948 with a redshift of~2.7.We analyzed 15.25 yr ofγ-ray data recorded by the Large... We report a gradual brighteningγ-ray source,4FGL J1718.5+4237,in 0.1-500.0 GeV,which may be associated with a blazar NVSS J171822+423948 with a redshift of~2.7.We analyzed 15.25 yr ofγ-ray data recorded by the Large Area Telescope on board the Fermi Gamma-ray Space Telescope and detected significantγ-ray emissions in the direction of the blazar with a test statistic(TS)of~135.Based on timing analysis using a 1 yr time bin,we have observed a gradual brightening inγ-ray emissions from the target.In our analysis,we categorize them into two states:Quiet(TS~0)and Loud(TS~226)states,with the distinction occurring in 2016 August(MJD57602.69).From the Quiet state to the brightest period(the last data point),theγ-ray flux in 0.1-500.0 GeV increased by more than 12-fold from<0.2×10^(-8)photons cm^(-1)s^(-1)to 2.6×10^(-8)photons cm^(-1)s^(-1).Additionally,we studied the spectral properties in detail for the Loud state and the overall data.While no significant variation was detected,both exhibited a spectral indexΓof~2.6.The origin of the brighteningγ-ray emissions from the target is not yet clear.Future long-term multi-wavelength observations and studies will provide insight into the astrophysical mechanisms of the target. 展开更多
关键词 GALAXIES active-blazars individual(4FGL J1718.5+4237)
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Photometric Analysis for Asteroid(81)Terpsichore using Convex Inversion and Phase Function Fitting Methods
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作者 Ao Wang Xiaobin Wang +5 位作者 Xiaoyun Xu Longhua Qin Quangui Gao Huaizhen Li Yong Xiao Hairu Zhao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期201-208,共8页
The shapes and rotation states(periods and pole orientations)of main-belt asteroids are important for understanding their formation and evolution.In order to obtain sufficient photometric data covering different appar... The shapes and rotation states(periods and pole orientations)of main-belt asteroids are important for understanding their formation and evolution.In order to obtain sufficient photometric data covering different apparitions for asteroid(81)Terpsichore,ground-based photometric observations in 2020 and 2021 were carried out.By combining published and newly obtained photometric data,we calculated the shape and spin parameters for(81)Terpsichore using the convex inversion method.With this method,we have derived a best fitted pole orientation—(22.2±_(3.1)^(3.3°),17.5±_(5.5)^(10.8°))with a spin period of 10.94±_(0.01)^(0.01)h.Based on the derived convex shape of(81)Terpsichore,we have fitted the H,G+1,G_(2)phase function using the calibrated TESS data and Gaia data after accounting for the lightcurve amplitude correction.As a result,we have derived its absolute magnitude H=8.68±_(0.19)^(0.22)mag with corresponding phase function parameters G_(1)=0.82±_(0.10)^(0.09)and G_(2)=0.02±_(0.02)^(0.03). 展开更多
关键词 asteroids:general minor planets asteroids:individual(Terpsichore) techniques:photometric
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Observation of Complex Organic Molecules Containing Peptide-like Bonds Toward Hot Core G358.93-0.03 MM1
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作者 Arijit Manna Sabyasachi Pal 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第7期181-189,共9页
In star formation regions,the complex organic molecules(COMs)that contain peptide bonds(-NH-C(=O)-)play a major role in the metabolic process because-NH-C(=O)-is connected to amino acids(R-CHNH_2-COOH).Over the past f... In star formation regions,the complex organic molecules(COMs)that contain peptide bonds(-NH-C(=O)-)play a major role in the metabolic process because-NH-C(=O)-is connected to amino acids(R-CHNH_2-COOH).Over the past few decades,many COMs containing peptide-like bonds have been detected in hot molecular cores(HMCs),hot corinos,and cold molecular clouds,however,their prebiotic chemistry is poorly understood.We present the first detection of the rotational emission lines of formamide(NH_2CHO)and isocyanic acid(HNCO),which contain peptide-like bonds toward the chemically rich HMC G358.93-0.03 MM1,using high-resolution and high-sensitivity Atacama Large Millimeter/submillimeter Array bands 6 and 7.We estimate that the column densities of NH_2CHO and HNCO toward G358.93-0.03 MM1 are(2.80±0.29)×10~(15)cm~(-2)and(1.80±0.42)×10~(16)cm~(-2)with excitation temperatures of 165±21 K and 170±32 K,respectively.The fractional abundances of NH_2CHO and HNCO toward G358.93-0.03 MM1 are(9.03±1.44)×10~(-10)and(5.80±2.09)×10^(-9).We compare the estimated abundances of NH_2CHO and HNCO with the existing threephase warm-up chemical model abundance values and notice that the observed and modeled abundances are very close.We conclude that NH_2CHO is produced by the reaction of NH_2and H_2CO in the gas phase toward G358.93-0.03 MM1.Likewise,HNCO is produced on the surface of grains by the reaction of NH and CO toward G358.93-0.03 MM1.We also find that NH_2CHO and HNCO are chemically linked toward G358.93-0.03 MM1. 展开更多
关键词 ISM individual objects(G358.93-0.03)-ISM abundances-ISM kinematics and dynamics-stars formation-astrochemistry
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A Possible γ-Ray Pulsation from PSR J1740-5340B in the Globular Cluster NGC 6397
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作者 Jiao Zheng Pengfei Zhang Li Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第1期285-291,共7页
Recently, a new radio millisecond pulsar(MSP) J1740-5340B, hosted in the globular cluster(GC) NGC 6397,was reported with a 5.78 ms spin period in an eclipsing binary system with a 1.97 days orbital period. Based on a ... Recently, a new radio millisecond pulsar(MSP) J1740-5340B, hosted in the globular cluster(GC) NGC 6397,was reported with a 5.78 ms spin period in an eclipsing binary system with a 1.97 days orbital period. Based on a modified radio ephemeris updated by tool tempo2, we analyze the ~15 yr γ-ray data obtained from the Large Area Telescope on board the Fermi Gamma-ray Space Telescope and detect PSR J1740-5340B's γ-ray pulsation at a confidence level of ~4σ with a weighted H-test value of ~26. By performing a phase-resolved analysis, the γ-ray luminosity in on-pulse interval of PSR J1740-5340B is L_(γ)~ 3.8 × 10^(33) erg s^(-1) using NGC 6397's distance of 2.48 kpc. And γ-rays from the on-pulse part of PSR J1740-5340B contribute ~90% of the total observed γ-ray emissions from NGC 6397. No significant γ-ray pulsation of another MSP J1740-5340A in the GC is detected.Considering that the previous four cases of MSPs in GCs, more data in γ-ray, X-ray, and radio are encouraged to finally confirm the γ-ray emissions from MSP J1740-5340B, especially starving for a precise ephemeris. 展开更多
关键词 gamma-rays:galaxies (stars:)pulsars:individual(PSR J1740-5340B) (Galaxy:)globular clusters:individual(NGC 6397)
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Analysis of metabolic characteristics of metabolic syndrome in elderly patients with gastric cancer by non-targeted metabolomics
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作者 Huan Zhang Wen-Bing Shen Lin Chen 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第6期2419-2428,共10页
BACKGROUND The relationship between metabolic syndrome(MetS)and gastric cancer(GC),which is a common metabolic disease,has attracted much attention.However,the specific metabolic characteristics of MetS in elderly pat... BACKGROUND The relationship between metabolic syndrome(MetS)and gastric cancer(GC),which is a common metabolic disease,has attracted much attention.However,the specific metabolic characteristics of MetS in elderly patients with GC remain unclear.AIM To investigate the differentially abundant metabolites and metabolic pathways between preoperative frailty and MetS in elderly patients with GC based on nontargeted metabolomics techniques.METHODS In this study,125 patients with nonfrail nonmeal GC were selected as the control group,and 50 patients with GC in the frail group were selected as the frail group.Sixty-five patients with GC combined with MetS alone were included in the MetS group,and 50 patients with GC combined with MetS were included in the MetS group.Nontargeted metabolomics techniques were used to measure plasma metabolite levels by ultrahigh-performance liquid chromatography-mass spectrometry.Multivariate statistical analysis was performed by principal component analysis,orthogonal partial least squares,pattern recognition analysis,cluster analysis,and metabolic pathway annotation.RESULTS A total of 125 different metabolites,including amino acids,glycerophospholipids,sphingolipids,fatty acids,sugars,nucleosides and nucleotides,and acidic compounds,were identified via nontargeted metabolomics techniques.Compared with those in the control group,there were 41,32,and 52 different metabolites in the MetS group,the debilitated group,and the combined group,respectively.Lipid metabolites were significantly increased in the MetS group.In the weak group,amino acids and most glycerol phospholipid metabolites decreased significantly,and fatty acids and sphingosine increased significantly.The combined group was characterized by significantly increased levels of nucleotide metabolites and acidic compounds.The alanine,aspartic acid,and glutamate metabolic pathways were obviously enriched in the asthenic group,and the glycerol and phospholipid metabolic pathways were obviously enriched in the combined group.CONCLUSION Elderly GC patients with simple frailty,simple combined MetS,and frailty combined with MetS have different metabolic characteristics,among which amino acid and glycerophospholipid metabolite levels are significantly lower in frail elderly GC patients,and comprehensive supplementation of fat and protein should be considered.Many kinds of metabolites,such as amino acids,lipids,nucleotides,and acidic compounds,are abnormally abundant in patients with MetS combined with fthenia,which may be related to tumor-related metabolic disorders. 展开更多
关键词 Nervous breakdown Metabolic syndrome Elderly individuals Gastric cancer Nontargeted metabolomics
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Long Term X-Ray Spectral Variations of the Seyfert-1 Galaxy Mrk 279
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作者 K.Akhila Ranjeev Misra +1 位作者 Savithri H.Ezhikode K.Jeena 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期307-314,共8页
We present the results from a long term X-ray analysis of Mrk 279 during the period 2018–2020.We use data from multiple missions–AstroSat,NuSTAR and XMM-Newton,for the purpose.The X-ray spectrum can be modeled as a ... We present the results from a long term X-ray analysis of Mrk 279 during the period 2018–2020.We use data from multiple missions–AstroSat,NuSTAR and XMM-Newton,for the purpose.The X-ray spectrum can be modeled as a double Comptonization along with the presence of neutral Fe Kαline emission,at all epochs.We determined the source’s X-ray flux and luminosity at these different epochs.We find significant variations in the source’s flux state.We also investigate the variations in the source’s spectral components during the observation period.We find that the photon index and hence the spectral shape follow the variations only over longer time periods.We probe the correlations between fluxes of different bands and their photon indices,and found no significant correlations between the parameters. 展开更多
关键词 galaxies:Seyfert galaxies:individual(Mrk 335) X-rays:galaxies
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