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Auto-parametric resonance of a continuous-beam-bridge model under two-point periodic excitation:an experimental investigation and stability analysis
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作者 Li Yuchun Shen Chao +1 位作者 Liu Wei Li Dong 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第2期445-454,共10页
The auto-parametric resonance of a continuous-beam bridge model subjected to a two-point periodic excitation is experimentally and numerically investigated in this study.An auto-parametric resonance experiment of the ... The auto-parametric resonance of a continuous-beam bridge model subjected to a two-point periodic excitation is experimentally and numerically investigated in this study.An auto-parametric resonance experiment of the test model is conducted to observe and measure the auto-parametric resonance of a continuous beam under a two-point excitation on columns.The parametric vibration equation is established for the test model using the finite-element method.The auto-parametric resonance stability of the structure is analyzed by using Newmark's method and the energy-growth exponent method.The effects of the phase difference of the two-point excitation on the stability boundaries of auto-parametric resonance are studied for the test model.Compared with the experiment,the numerical instability predictions of auto-parametric resonance are consistent with the test phenomena,and the numerical stability boundaries of auto-parametric resonance agree with the experimental ones.For a continuous beam bridge,when the ratio of multipoint excitation frequency(applied to the columns)to natural frequency of the continuous girder is approximately equal to 2,the continuous beam may undergo a strong auto-parametric resonance.Combined with the present experiment and analysis,a hypothesis of Volgograd Bridge's serpentine vibration is discussed. 展开更多
关键词 auto-parametric resonance continuous beam bridge model two-point excitation experimental investigation stability analysis vibration of Volgograd Bridge
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Investigation and Analysis of Main Diseases of Landscape Plants in the Main Urban Area of Lu'an City
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作者 Gao LIU Hao SONG Juanjuan HU 《Plant Diseases and Pests》 2024年第1期18-21,共4页
To figure out the disease occurrence of landscape plants in the main urban area of Lu'an City,the author investigated the disease occurrence of landscape plants in park green space,residential green space,unit att... To figure out the disease occurrence of landscape plants in the main urban area of Lu'an City,the author investigated the disease occurrence of landscape plants in park green space,residential green space,unit attached green space and main road in the area under administration.The survey results showed that there were 29 species of urban landscape plant diseases,mainly powdery mildew and spot diseases.According to the characteristics of the diseases,the causes and problems of the diseases were analyzed,and the corresponding prevention and control measures were put forward. 展开更多
关键词 Landscape plant Disease species investigation Status analysis Lu'an City
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Model reduction of fractional impedance spectra for time–frequency analysis of batteries, fuel cells, and supercapacitors 被引量:1
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作者 Weiheng Li Qiu-An Huang +6 位作者 Yuxuan Bai Jia Wang Linlin Wang Yuyu Liu Yufeng Zhao Xifei Li Jiujun Zhang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期108-141,共34页
Joint time–frequency analysis is an emerging method for interpreting the underlying physics in fuel cells,batteries,and supercapacitors.To increase the reliability of time–frequency analysis,a theoretical correlatio... Joint time–frequency analysis is an emerging method for interpreting the underlying physics in fuel cells,batteries,and supercapacitors.To increase the reliability of time–frequency analysis,a theoretical correlation between frequency-domain stationary analysis and time-domain transient analysis is urgently required.The present work formularizes a thorough model reduction of fractional impedance spectra for electrochemical energy devices involving not only the model reduction from fractional-order models to integer-order models and from high-to low-order RC circuits but also insight into the evolution of the characteristic time constants during the whole reduction process.The following work has been carried out:(i)the model-reduction theory is addressed for typical Warburg elements and RC circuits based on the continued fraction expansion theory and the response error minimization technique,respectively;(ii)the order effect on the model reduction of typical Warburg elements is quantitatively evaluated by time–frequency analysis;(iii)the results of time–frequency analysis are confirmed to be useful to determine the reduction order in terms of the kinetic information needed to be captured;and(iv)the results of time–frequency analysis are validated for the model reduction of fractional impedance spectra for lithium-ion batteries,supercapacitors,and solid oxide fuel cells.In turn,the numerical validation has demonstrated the powerful function of the joint time–frequency analysis.The thorough model reduction of fractional impedance spectra addressed in the present work not only clarifies the relationship between time-domain transient analysis and frequency-domain stationary analysis but also enhances the reliability of the joint time–frequency analysis for electrochemical energy devices. 展开更多
关键词 battery fuel cell supercapacitor fractional impedance spectroscopy model reduction time-frequency analysis
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Novel Investigation of Stochastic Fractional Differential Equations Measles Model via the White Noise and Global Derivative Operator Depending on Mittag-Leffler Kernel 被引量:1
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作者 Saima Rashid Fahd Jarad 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2289-2327,共39页
Because of the features involved with their varied kernels,differential operators relying on convolution formulations have been acknowledged as effective mathematical resources for modeling real-world issues.In this p... Because of the features involved with their varied kernels,differential operators relying on convolution formulations have been acknowledged as effective mathematical resources for modeling real-world issues.In this paper,we constructed a stochastic fractional framework of measles spreading mechanisms with dual medication immunization considering the exponential decay and Mittag-Leffler kernels.In this approach,the overall population was separated into five cohorts.Furthermore,the descriptive behavior of the system was investigated,including prerequisites for the positivity of solutions,invariant domain of the solution,presence and stability of equilibrium points,and sensitivity analysis.We included a stochastic element in every cohort and employed linear growth and Lipschitz criteria to show the existence and uniqueness of solutions.Several numerical simulations for various fractional orders and randomization intensities are illustrated. 展开更多
关键词 Measles epidemic model Atangana-Baleanu Caputo-Fabrizio differential operators existence and uniqueness qualitative analysis Newton interpolating polynomial
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Experimental investigation on coal pore-fracture variation and fractal characteristics synergistically affected by solvents for improving clean gas extraction
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作者 Feilin Han Sheng Xue +3 位作者 Chunshan Zheng Zhongwei Chen Guofu Li Bingyou Jiang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第3期413-425,共13页
Chemical solvents instead of pure water being as hydraulic fracturing fluid could effectively increase permeability and improve clean methane extraction efficiency.However,pore-fracture variation features of lean coal... Chemical solvents instead of pure water being as hydraulic fracturing fluid could effectively increase permeability and improve clean methane extraction efficiency.However,pore-fracture variation features of lean coal synergistically affected by solvents have not been fully understood.Ultrasonic testing,nuclear magnetic resonance analysis,liquid phase mass spectrometry was adopted to comprehensively analyze pore-fracture change characteristics of lean coal treated by combined solvent(NMP and CS_(2)).Meanwhile,quantitative characterization of above changing properties was conducted using geometric fractal theory.Relationship model between permeability,fractal dimension and porosity were established.Results indicate that the end face fractures of coal are well developed after CS2and combined solvent treatments,of which,end face box-counting fractal dimensions range from 1.1227 to 1.4767.Maximum decreases in ultrasonic longitudinal wave velocity of coal affected by NMP,CS_(2)and combined solvent are 2.700%,20.521%,22.454%,respectively.Solvent treatments could lead to increasing amount of both mesopores and macropores.Decrease ratio of fractal dimension Dsis 0.259%–2.159%,while permeability increases ratio of NMR ranges from 0.1904 to 6.4486.Meanwhile,combined solvent could dissolve coal polar and non-polar small molecules and expand flow space.Results could provide reference for solvent selection and parameter optimization of permeability-enhancement technology. 展开更多
关键词 Clean gas extraction Chemical solvent Experimental investigation Fractal characteristics Pore fracture
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Evaluation of the seismic behavior of reinforced concrete structures with flat slab-column gravity frame and shear walls through nonlinear analysis methods
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作者 M.A.Najafgholipour S.Heidarian Radbakhsh E.Erfani 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第3期713-726,共14页
This paper presents an investigation of the seismic behavior of reinforced concrete(RC)structures in which shear walls are the main lateral load-resisting elements and the participation of flat slab floor systems is n... This paper presents an investigation of the seismic behavior of reinforced concrete(RC)structures in which shear walls are the main lateral load-resisting elements and the participation of flat slab floor systems is not considered in the seismic design procedure.In this regard,the behavior of six prototype structures(with different heights and plan layouts)is investigated through nonlinear static and time history analyses,implemented in the OpenSees platform.The results of the analyses are presented in terms of the behavior of the slab-column connections and their mode of failure at different loading stages.Moreover,the global response of the buildings is discussed in terms of some parameters,such as lateral overstrength due to the gravity flat slab-column frames.According to the nonlinear static analyses,in structures in which the slab-column connections were designed only for gravity loads,the slab-column connections exhibited a punching mode of failure even in the early stages of loading.However,the punching failure was eliminated in structures in which a minimum transverse reinforcement recommended in ACI 318(2019)was provided in the slabs at joint regions.Furthermore,despite neglecting the contribution of gravity flat slab-column frames in the lateral load resistance of the structures,a relatively significant overstrength was imposed on the structures by the gravity frames. 展开更多
关键词 RC flat slab-column frames seismic behavior nonlinear analysis time history analysis
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Investigation of point defect evolution and Voronoi cluster analysis for magnesium during nanoindentation 被引量:2
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作者 Pragyan Goswami Snehanshu Pal Manoj Gupta 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第3期1029-1042,共14页
The present study investigates the effect of nanoindentation on single-crystal magnesium specimens using the embedded-atom method potential in molecular dynamics simulation.Analyses are done under dynamic loading wher... The present study investigates the effect of nanoindentation on single-crystal magnesium specimens using the embedded-atom method potential in molecular dynamics simulation.Analyses are done under dynamic loading where the load-bearing capacity and change in the structural configuration are studied on the basal(Z-direction)and two prismatic planes(X-and Y-directions)with varying indenter velocities.The investigation of structural evolution is done using atomic displacement analyses to measure the net magnitude of displacement,atomic strain analyses to evaluate the shear strain developed in the process,and Wigner-Seitz defect analyses to calculate the total vacancies at varied timesteps.Furthermore,Voronoi analyses are done when indented on the basal plane to identify the cluster distribution at different planar depths of the specimen.From the analyses,it has been observed that the load-bearing capacity of the specimen varies with the indentation velocity and the direction of indentation on the specimen.Additionally,it is seen that the observed shear and total atomic displacement in the Z-direction is the least in comparison to the other two axes.The partial dislocation 1/3<-12-10>is seen to be majorly present and the population of dislocation loops is more abundant for lower indenter velocities.Furthermore,clusters<0,4,4,6>and<0,6,0,8>are the major indices developed during nanoindentation on the basal plane where they exhibit symmetrical distribution as observed from the Z-direction. 展开更多
关键词 MAGNESIUM Molecular dynamics NANOINDENTATION Voronoi analysis Wigner-Seitz defect analysis
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Erratum to:Vibration analysis of a gear-rotor-bearing system with outer-ring spalling and misalignment
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作者 徐宏阳 赵翔 +3 位作者 马辉 罗忠 韩清凯 闻邦椿 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第3期1032-1032,共1页
Because of an unfortunate mistake during the production of this article,Figure 13 was wrongly inserted.The corrected Figure 13 is shown as follows.
关键词 FIGURE outer analysis
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Trends and hotspots in gastrointestinal neoplasms risk assessment: A bibliometric analysis from 1984 to 2022
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作者 Qiang-Qiang Fu Le Ma +5 位作者 Xiao-Min Niu Hua-Xin Zhao Xu-Hua Ge Hua Jin De-Hua Yu Sen Yang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第6期2842-2861,共20页
BACKGROUND Gastrointestinal neoplasm(GN)significantly impact the global cancer burden and mortality,necessitating early detection and treatment.Understanding the evolution and current state of research in this field i... BACKGROUND Gastrointestinal neoplasm(GN)significantly impact the global cancer burden and mortality,necessitating early detection and treatment.Understanding the evolution and current state of research in this field is vital.AIM To conducts a comprehensive bibliometric analysis of publications from 1984 to 2022 to elucidate the trends and hotspots in the GN risk assessment research,focusing on key contributors,institutions,and thematic evolution.METHODS This study conducted a bibliometric analysis of data from the Web of Science Core Collection database using the"bibliometrix"R package,VOSviewer,and CiteSpace.The analysis focused on the distribution of publications,contributions by institutions and countries,and trends in keywords.The methods included data synthesis,network analysis,and visualization of international collaboration networks.RESULTS This analysis of 1371 articles on GN risk assessment revealed a notable evolution in terms of research focus and collaboration.It highlights the United States'critical role in advancing this field,with significant contributions from institutions such as Brigham and Women's Hospital and the National Cancer Institute.The last five years,substantial advancements have been made,representing nearly 45%of the examined literature.Publication rates have dramatically increased,from 20 articles in 2002 to 112 in 2022,reflecting intensified research efforts.This study underscores a growing trend toward interdisciplinary and international collaboration,with the Journal of Clinical Oncology standing out as a key publication outlet.This shift toward more comprehensive and collaborative research methods marks a significant step in addressing GN risks.CONCLUSION This study underscores advancements in GN risk assessment through genetic analyses and machine learning and reveals significant geographical disparities in research emphasis.This calls for enhanced global collaboration and integration of artificial intelligence to improve cancer prevention and treatment accuracy,ultimately enhancing worldwide patient care. 展开更多
关键词 Gastrointestinal neoplasms Bibliometric analysis Risk assessment Network analysis Research trends
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Molecular cloning,characterization and promoter analysis of LbgCWIN1 and its expression profiles in response to exogenous sucrose during in vitro bulblet initiation in lily
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作者 Cong Gao Shiqi Li +4 位作者 Yunchen Xu Yue Liu Yiping Xia Ziming Ren Yun Wu 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期545-555,共11页
Lily(Lilium spp.) is an important ornamental flower, which is mainly propagated by bulbs. Cell wall invertases(CWINs), which catalyze the irreversibly conversion of sucrose into glucose and fructose in the extracellul... Lily(Lilium spp.) is an important ornamental flower, which is mainly propagated by bulbs. Cell wall invertases(CWINs), which catalyze the irreversibly conversion of sucrose into glucose and fructose in the extracellular space, are key enzymes participating in sucrose allocation in higher plants. Previous studies have shown that CWINs play an essential role in bulblet initiation process in bulbous crops, but the underlying molecular mechanism remains unclear. Here, a CWIN gene of Lilium brownii var. giganteum(Lbg) was identified and amplified from genomic DNA. Quantitative RT-PCR assays revealed that the expression level of LbgCWIN1 was highly upregulated exactly when the endogenous starch degraded in non-sucrose medium during in vitro bulblet initiation in Lbg. Phylogenetic relationship, motif, and domain analysis of LbgCWIN1 protein and CWINs in other plant species showed that all sequences of these CWIN proteins were highly conserved. The promoter sequence of LbgCWIN1 possessed a number of alpha-amylase-, phytohormone-, light-and stress-responsive cis-elements. Meanwhile, β-glucuronidase(GUS) assay showed that the 459 bp upstream fragment from the translational start site displayed maximal promoter activity. These results revealed that LbgCWIN1 might function in the process of in vitro bulblet initiation and be in the response to degradation of endogenous starch. 展开更多
关键词 Lilium brownii var.giganteum LbgCWIN1 Phylogenetic analysis Promoter analysis Bulblet initiation
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Action of circulating and infiltrating B cells in the immune microenvironment of colorectal cancer by single-cell sequencing analysis
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作者 Jing-Po Zhang Bing-Zheng Yan +1 位作者 Jie Liu Wei Wang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第6期2683-2696,共14页
BACKGROUND The complexity of the immune microenvironment has an impact on the treatment of colorectal cancer(CRC),one of the most prevalent malignancies worldwide.In this study,multi-omics and single-cell sequencing t... BACKGROUND The complexity of the immune microenvironment has an impact on the treatment of colorectal cancer(CRC),one of the most prevalent malignancies worldwide.In this study,multi-omics and single-cell sequencing techniques were used to investigate the mechanism of action of circulating and infiltrating B cells in CRC.By revealing the heterogeneity and functional differences of B cells in cancer immunity,we aim to deepen our understanding of immune regulation and provide a scientific basis for the development of more effective cancer treatment strategies.AIM To explore the role of circulating and infiltrating B cell subsets in the immune microenvironment of CRC,explore the potential driving mechanism of B cell development,analyze the interaction between B cells and other immune cells in the immune microenvironment and the functions of communication molecules,and search for possible regulatory pathways to promote the anti-tumor effects of B cells.METHODS A total of 69 paracancer(normal),tumor and peripheral blood samples were collected from 23 patients with CRC from The Cancer Genome Atlas database(https://portal.gdc.cancer.gov/).After the immune cells were sorted by multicolor flow cytometry,the single cell transcriptome and B cell receptor group library were sequenced using the 10X Genomics platform,and the data were analyzed using bioinformatics tools such as Seurat.The differences in the number and function of B cell infiltration between tumor and normal tissue,the interaction between B cell subsets and T cells and myeloid cell subsets,and the transcription factor regulatory network of B cell subsets were explored and analyzed.RESULTS Compared with normal tissue,the infiltrating number of CD20+B cell subsets in tumor tissue increased significantly.Among them,germinal center B cells(GCB)played the most prominent role,with positive clone expansion and heavy chain mutation level increasing,and the trend of differentiation into memory B cells increased.However,the number of plasma cells in the tumor microenvironment decreased significantly,and the plasma cells secreting IgA antibodies decreased most obviously.In addition,compared with the immune microenvironment of normal tissues,GCB cells in tumor tissues became more closely connected with other immune cells such as T cells,and communication molecules that positively regulate immune function were significantly enriched.CONCLUSION The role of GCB in CRC tumor microenvironment is greatly enhanced,and its affinity to tumor antigen is enhanced by its significantly increased heavy chain mutation level.Meanwhile,GCB has enhanced its association with immune cells in the microenvironment,which plays a positive anti-tumor effect. 展开更多
关键词 Colorectal cancer Multi-omics analysis Single-cell sequencing analysis Immune microenvironment Infiltrating B cells
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Intertwined depressive and cognitive trajectories and the risk of dementia and death in older adults:a competing risk analysis
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作者 Ziyang Ren Lirong Nie +1 位作者 Yushan Du Jufen Liu 《General Psychiatry》 CSCD 2024年第2期207-215,共9页
Background Depressive symptoms and cognitive impairment often interact,rendering their associations controversial.To date,their joint trajectories and associations with dementia and death remain underexplored.Aims To ... Background Depressive symptoms and cognitive impairment often interact,rendering their associations controversial.To date,their joint trajectories and associations with dementia and death remain underexplored.Aims To explore the interactions between depressive symptoms and cognitive function,their developmental trajectories and the associations with all-cause dementia,Alzheimer’s disease(AD)and all-cause death in older adults.Methods Data were from the Health and Retirement Study.Depressive symptoms and cognitive function were measured using the 8-item Centre for Epidemiologic Studies Depression Scale and the Telephone Interview of Cognitive Status,respectively.All-cause dementia and AD were defined by self-reported or proxy-reported physician diagnoses.All-cause death was determined by interviews.The restricted cubic spline,group-based trajectory modelling and subdistribution hazard regression were used.Results Significant interactions between depressive symptoms and cognitive function in 2010 in their association with new-onset all-cause dementia and AD from 2010 to 2020 were found,especially in women(p for interaction<0.05).Independent trajectory analysis showed that emerging or high(vs no)depressive trajectories and poor or rapidly decreased cognitive trajectories(vs very good)from 1996 to 2010 were at significantly higher risk of subsequent all-cause dementia,AD and all-cause death.15 joint trajectories of depressive symptoms and cognitive function from 1996 to 2010 were determined,where rapidly decreased cognitive function was more common in those with no depressive symptoms.Compared with older adults with the trajectory of no depressive symptoms and very good cognitive function,those with the trajectory of no depressive symptoms but rapidly decreased cognitive function were much more likely to develop new-onset all-cause dementia and death,with subdistribution hazard ratios(95%confidence intervals)of 4.47(2.99 to 6.67)and 1.84(1.43 to 2.36),especially in women.Conclusions To effectively mitigate the risk of dementia and death,it is crucial to acknowledge the importance of preventing cognitive decline in older adults without depressive symptoms,particularly in women. 展开更多
关键词 DEATH analysis RENDERING
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Prevalence of prolonged grief disorder and its symptoms among bereaved individuals in China:a systematic review and meta-analysis
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作者 Meng-Di Yuan Jun-Fa Liu Bao-Liang Zhong 《General Psychiatry》 CSCD 2024年第2期177-188,共12页
Background The prevalence of prolonged grief disorder(PGD)and its symptoms among the bereaved population in China vary considerably.Aims This meta-analysis aims to estimate the prevalence of PGD and its symptoms among... Background The prevalence of prolonged grief disorder(PGD)and its symptoms among the bereaved population in China vary considerably.Aims This meta-analysis aims to estimate the prevalence of PGD and its symptoms among bereaved individuals in China.Methods We conducted a literature search in major Chinese and English databases from their inception to 4 October 2023,for cross-sectional studies on the prevalence of PGD or its symptoms in bereaved Chinese individuals.The risk of bias of the included studies and certainty of the evidence were assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Studies Reporting Prevalence Data(‘JBI checklist’)and the Grading of Recommendations,Assessment,Development and Evaluations(GRADE),respectively.The‘metaprop’package in R V.4.1.2 was used to synthesise the prevalence.Results A total of 28 studies involving 10994 bereaved individuals were included in the analysis,with JBI checklist scores between 3 and 7.The combined prevalence(95%confidence interval)of PGD and its symptoms was 8.9%(4.2%to 17.6%)and 32.4%(18.2%to 50.8%),respectively.PGD and its symptoms were most prevalent among those who had lost their only child(22.7%)and those bereaved by earthquakes(80.4%),respectively.The GRADE system assigned a very low certainty level to the evidence for the pooled prevalence of PGD and its symptoms.Conclusions The pooled prevalence of PGD and its symptoms indicate a potential high need for grief counselling services among bereaved individuals in China.This need is particularly pronounced in those who have lost their only child and those bereaved due to earthquakes.Further methodologically rigorous studies are needed to provide more accurate prevalence estimates.PROSPERO registration number CRD42023432553. 展开更多
关键词 SYMPTOMS PREVALENCE analysis
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Harnessing the Market Potential of the Bamboo Industry in Central Luzon, Philippines: An Analysis of the Internal and External Environment
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作者 Edgelly Galvez Vitug Sarah Calma Alvarez 《Open Journal of Ecology》 2024年第5期395-418,共24页
The bamboo industry in Central Luzon holds significant promise for economic development and environmental sustainability. This study aims to analyze the internal and external factors influencing the bamboo industry in... The bamboo industry in Central Luzon holds significant promise for economic development and environmental sustainability. This study aims to analyze the internal and external factors influencing the bamboo industry in the region through SWOT and PESTLE analyses. Based on a focus group discussion involving key industry players, the study explores the industry’s strengths, weaknesses, opportunities, and threats, as well as political, economic, social, technological, legal, and environmental factors. Findings reveal the importance of comprehensive strategies that address political stability, economic growth, consumer awareness, technological advancement, legal compliance, and environmental sustainability. Recommendations include capacity-building for production and marketing, the establishment of bamboo treatment facilities, and advocacy for supportive policies. By addressing these factors, the bamboo industry in Central Luzon can realize its potential for socio-economic development and environmental stewardship. 展开更多
关键词 BAMBOO SWOT analysis PESTLE analysis Business Environment Value Addition SUSTAINABILITY Market Potential
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R-Factor Analysis of Data Based on Population Models Comprising R- and Q-Factors Leads to Biased Loading Estimates
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作者 André Beauducel 《Open Journal of Statistics》 2024年第1期38-54,共17页
Effects of performing an R-factor analysis of observed variables based on population models comprising R- and Q-factors were investigated. Although R-factor analysis of data based on a population model comprising R- a... Effects of performing an R-factor analysis of observed variables based on population models comprising R- and Q-factors were investigated. Although R-factor analysis of data based on a population model comprising R- and Q-factors is possible, this may lead to model error. Accordingly, loading estimates resulting from R-factor analysis of sample data drawn from a population based on a combination of R- and Q-factors will be biased. It was shown in a simulation study that a large amount of Q-factor variance induces an increase in the variation of R-factor loading estimates beyond the chance level. Tests of the multivariate kurtosis of observed variables are proposed as an indicator of possible Q-factor variance in observed variables as a prerequisite for R-factor analysis. 展开更多
关键词 R-Factor analysis Q-Factor analysis Loading Bias Model Error Multivariate Kurtosis
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Phytochemical Analysis and Antimicrobial Activity of Lawsonia inermis Leaf Extracts from Burkina Faso
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作者 Ollo Youl Soumaïla Konaté +10 位作者 Ernest N. Sombié Rainatou Boly Boukaré Kaboré Moumouni Koala Arouna Zoungrana Saybou Savadogo Christian Marc Tahita Innocent Valea Halidou Tinto Adama Hilou Maminata Traoré-Coulibaly 《American Journal of Plant Sciences》 CAS 2024年第7期552-576,共25页
Lawsonia inermis is a hairless plant growing in various regions of North Africa, the Indian subcontinent, and the Middle East. It possesses many medicinal attributes, including curative properties against infectious d... Lawsonia inermis is a hairless plant growing in various regions of North Africa, the Indian subcontinent, and the Middle East. It possesses many medicinal attributes, including curative properties against infectious dermatoses. This study was carried out to evaluate the phytochemical profile of the crude ethanolic extract of the plant leaves and its fractions as well as their antimicrobial activities. The phytochemical profile was performed using high-performance thin-layer chromatography (HPTLC), gas chromatography-mass spectrometry (GC-MS), and high-performance liquid chromatography (HPLC). Additionally, the phenolic and flavonoid contents were determined using the Folin-Ciocalteu spectrophotometric and the aluminum trichloride methods. Antimicrobial activity was tested using disc diffusion and microdilution methods. The presence of flavonoids, tannins, sterols, and triterpenes was revealed. GC-MS detected twelve compounds main compounds consisting of saturated and unsaturated fatty acids and phenolic and terpenoid compounds among twenty-seven components. HPLC also detected high contents of phenolic acids and flavonoids. The most abundant triterpene and sterols were ursolic acid (around 43.14 g/100g DW, 13.9 g/100g dry weight (DW), and 0.68 g/100g DW) in the crude ethanolic extract of leaves (FeLi), hexane fraction (FHLi) and dichloromethane fraction (FDLi), respectively and, β-sitosterol in FeLi (56.7 mg/100g DW), FHLi (10.55 g/100g DW), FDLi (106.1 mg/100g DW) and butanol fraction (FBLi) (357.4 mg/100g DW). Among the flavonoids, rutin = 3.24 g/100g and quercetin = 0.63 g/100g in the ethanolic extract, rutin = 15.73 g/100g in the dichloromethane fraction, and rutin = 0.23 g/100g) in the aqueous fraction;and among phenolic compounds, caffeic acid (37.65 g/100g DW) and vanillic acid (22.70 g/100g DW) were the most important in the ethyl acetate fraction (FAeLi). All organic fractions exhibited interesting antibacterial and antifungal activities against the tested strains, with the best activity recorded with the dichloromethane and ethyl acetate fractions. The leaf extracts’ phytochemical profile and antimicrobial activity support the use of Lawsonia inermis against infectious skin diseases. 展开更多
关键词 Lawsonia inermis Phytochemical Profile HPLC GC-MS analysis Antimicrobial Activity
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Screening biomarkers for spinal cord injury using weighted gene co-expression network analysis and machine learning
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作者 Xiaolu Li Ye Yang +3 位作者 Senming Xu Yuchang Gui Jianmin Chen Jianwen Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第12期2723-2734,共12页
Immune changes and inflammatory responses have been identified as central events in the pathological process of spinal co rd injury.They can greatly affect nerve regeneration and functional recovery.However,there is s... Immune changes and inflammatory responses have been identified as central events in the pathological process of spinal co rd injury.They can greatly affect nerve regeneration and functional recovery.However,there is still limited understanding of the peripheral immune inflammato ry response in spinal cord inju ry.In this study.we obtained microRNA expression profiles from the peripheral blood of patients with spinal co rd injury using high-throughput sequencing.We also obtained the mRNA expression profile of spinal cord injury patients from the Gene Expression Omnibus(GEO)database(GSE151371).We identified 54 differentially expressed microRNAs and 1656 diffe rentially expressed genes using bioinformatics approaches.Functional enrichment analysis revealed that various common immune and inflammation-related signaling pathways,such as neutrophil extracellular trap formation pathway,T cell receptor signaling pathway,and nuclear factor-κB signal pathway,we re abnormally activated or inhibited in spinal cord inju ry patient samples.We applied an integrated strategy that combines weighted gene co-expression network analysis,LASSO logistic regression,and SVM-RFE algorithm and identified three biomarke rs associated with spinal cord injury:ANO10,BST1,and ZFP36L2.We verified the expression levels and diagnostic perfo rmance of these three genes in the original training dataset and clinical samples through the receiver operating characteristic curve.Quantitative polymerase chain reaction results showed that ANO20 and BST1 mRNA levels were increased and ZFP36L2 mRNA was decreased in the peripheral blood of spinal cord injury patients.We also constructed a small RNA-mRNA interaction network using Cytoscape.Additionally,we evaluated the proportion of 22 types of immune cells in the peripheral blood of spinal co rd injury patients using the CIBERSORT tool.The proportions of naive B cells,plasma cells,monocytes,and neutrophils were increased while the proportions of memory B cells,CD8^(+)T cells,resting natural killer cells,resting dendritic cells,and eosinophils were markedly decreased in spinal cord injury patients increased compared with healthy subjects,and ANO10,BST1 and ZFP26L2we re closely related to the proportion of certain immune cell types.The findings from this study provide new directions for the development of treatment strategies related to immune inflammation in spinal co rd inju ry and suggest that ANO10,BST2,and ZFP36L2 are potential biomarkers for spinal cord injury.The study was registe red in the Chinese Clinical Trial Registry(registration No.ChiCTR2200066985,December 12,2022). 展开更多
关键词 bioinformatics analysis BIOMARKER CIBERSORT GEO dataset LASSO miRNA-mRNA network RNA sequencing spinal cord injury SVM-RFE weighted gene co-expression network analysis
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Stochastic Analysis and Modeling of Velocity Observations in Turbulent Flows
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作者 Evangelos Rozos Jorge Leandro Demetris Koutsoyiannis 《Journal of Environmental & Earth Sciences》 CAS 2024年第1期45-56,共12页
Highly turbulent water flows,often encountered near human constructions like bridge piers,spillways,and weirs,display intricate dynamics characterized by the formation of eddies and vortices.These formations,varying i... Highly turbulent water flows,often encountered near human constructions like bridge piers,spillways,and weirs,display intricate dynamics characterized by the formation of eddies and vortices.These formations,varying in sizes and lifespans,significantly influence the distribution of fluid velocities within the flow.Subsequently,the rapid velocity fluctuations in highly turbulent flows lead to elevated shear and normal stress levels.For this reason,to meticulously study these dynamics,more often than not,physical modeling is employed for studying the impact of turbulent flows on the stability and longevity of nearby structures.Despite the effectiveness of physical modeling,various monitoring challenges arise,including flow disruption,the necessity for concurrent gauging at multiple locations,and the duration of measurements.Addressing these challenges,image velocimetry emerges as an ideal method in fluid mechanics,particularly for studying turbulent flows.To account for measurement duration,a probabilistic approach utilizing a probability density function(PDF)is suggested to mitigate uncertainty in estimated average and maximum values.However,it becomes evident that deriving the PDF is not straightforward for all turbulence-induced stresses.In response,this study proposes a novel approach by combining image velocimetry with a stochastic model to provide a generic yet accurate description of flow dynamics in such applications.This integration enables an approach based on the probability of failure,facilitating a more comprehensive analysis of turbulent flows.Such an approach is essential for estimating both short-and long-term stresses on hydraulic constructions under assessment. 展开更多
关键词 Smart modeling Turbulent flows Data analysis Stochastic analysis Image velocimetry
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Modeling Analysis of Factors Influencing Wind-Borne Seed Dispersal: A Case Study on Dandelion
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作者 Kemeng Xue 《American Journal of Plant Sciences》 CAS 2024年第4期252-267,共16页
A weed is a plant that thrives in areas of human disturbance, such as gardens, fields, pastures, waysides, and waste places where it is not intentionally cultivated. Dispersal affects community dynamics and vegetation... A weed is a plant that thrives in areas of human disturbance, such as gardens, fields, pastures, waysides, and waste places where it is not intentionally cultivated. Dispersal affects community dynamics and vegetation response to global change. The process of seed disposal is influenced by wind, which plays a crucial role in determining the distance and probability of seed dispersal. Existing models of seed dispersal consider wind direction but fail to incorporate wind intensity. In this paper, a novel seed disposal model was proposed in this paper, incorporating wind intensity based on relevant references. According to various climatic conditions, including temperate, arid, and tropical regions, three specific regions were selected to establish a wind dispersal model that accurately reflects the density function distribution of dispersal distance. Additionally, dandelions growth is influenced by a multitude of factors, encompassing temperature, humidity, climate, and various environmental variables that necessitate meticulous consideration. Based on Factor Analysis model, which completely considers temperature, precipitation, solar radiation, wind, and land carrying capacity, a conclusion is presented, indicating that the growth of seeds is primarily influenced by plant attributes and climate conditions, with the former exerting a relatively stronger impact. Subsequently, the remaining two plants were chosen based on seed weight, yielding consistent conclusion. 展开更多
关键词 Seed Dispersal Wind Intensity Climatic Effect Factor analysis Model
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Gene characterization and phylogenetic analysis of four mitochondrial genomes in Caenogastropoda
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作者 Jiangyong Qu Wanqi Yang +7 位作者 Xindong Teng Li Xu Dachuan Zhang Zhikai Xing Shuang Wang Xiumei Liu Lijun Wang Xumin Wang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第2期137-150,共14页
Caenogastropoda is a highly diverse group,containing~60%of all existing gastropods.Species in this subclass predominantly inhabit marine environments and have a high ecological and economic value.Owing to the increase... Caenogastropoda is a highly diverse group,containing~60%of all existing gastropods.Species in this subclass predominantly inhabit marine environments and have a high ecological and economic value.Owing to the increase in relevant phylogenetic studies,our understanding of between species relatedness in Caenogastropoda has improved.However,the biodiversity,taxonomic status,and phylogenetic relationships of this group remain unclear.In the present study,we performed next-generation sequencing of four complete mitochondrial genomes from three families(Buccinidae,Columbellidae,and Cypraeidae)and the four mitogenomes were classical circular structures,with a length of 16177 bp in Volutharpa ampullacea,16244 bp in Mitrella albuginosa,16926bp in Mauritia arabica asiatica and 15422 bp in Erronea errones.Base composition analysis indicated that whole sequences were biased toward A and T.Then compared them with 171 complete mitochondrial genomes of Caenogastropoda.The phylogenetic relationship of Caenogastropoda derived from Maximum Likelihood(ML)and Bayesian Inference(BI)trees constructed based on CDS sequences was consistent with the results of traditional morphological analysis,with all three families showing close relationships.This study supported Caenogastropoda at the molecular level as a separate clade of Mollusca.According to our divergence time estimations,Caenogastropoda was formed during the middle Triassic period(~247.2–237 Ma).Our novel mitochondrial genomes provide evidence for the speciation of Caenogastropoda in addition to elucidating the mitochondrial genomic evolution of this subclass. 展开更多
关键词 mitochondrial genome phylogenetic analysis CAENOGASTROPODA
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