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Migration Networks Pattern of China’s Floating Population from the Perspective of Complex Network
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作者 LIU Wangbao CHEN Ranran 《Chinese Geographical Science》 SCIE CSCD 2024年第2期327-341,共15页
Since China’s reform and opening-up,the growing disparity between urban and rural areas and regions has led to massive migration.With China’s Rural Revitalization Strategy and the industrial transfer from the easter... Since China’s reform and opening-up,the growing disparity between urban and rural areas and regions has led to massive migration.With China’s Rural Revitalization Strategy and the industrial transfer from the eastern coastal areas to the inland,the migration direction and pattern of the floating population have undergone certain changes.Using the 2017 China Migrants Dynamic Survey(CMDS),excluding Hong Kong,Macao,and Taiwan regions of China,organized by China’s National Health Commission,the relationship matrix of the floating population is constructed according to the inflow place of the interviewees and their outflow place(the location of the registered residence)in the questionnaire survey.We then apply the complex network model to analyze the migration direction and network pattern of China’s floating population from the city scale.The migration network shows an obvious hierarchical agglomeration.The first-,second-,third-and fourth-tier distribution cities are municipalities directly under the central government,provincial capital cities,major cities in the central and western regions and ordinary cities in all provinces,respectively.The migration trend is from the central and western regions to the eastern coastal areas.The migration network has‘small world’characteristics,forming nine communities.It shows that most node cities in the same community are closely linked and geographically close,indicating that the migration network of floating population is still affected by geographical proximity.Narrowing the urban-rural and regional differences will promote the rational distribution this population.It is necessary to strengthen the reform of the registered residence system,so that the floating population can enjoy urban public services comparable to other populations,and allow migrants to live and work in peace. 展开更多
关键词 complex network floating population migration network spatial pattern community structure
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Research on Cultural Consumption and Urban Integration of Floating Population
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作者 Zhang Rui Dai Xiaowen 《Contemporary Social Sciences》 2024年第2期16-33,共18页
This paper examined the relationship between cultural consumption and the floating population’s integration into host cities based on data from China’s Seventh National Population Census and the 2018 China Migrants ... This paper examined the relationship between cultural consumption and the floating population’s integration into host cities based on data from China’s Seventh National Population Census and the 2018 China Migrants Dynamic Survey(CMDS).The findings indicate that improving the floating population’s consumption level and quality,especially the quality of development-oriented cultural consumption,can significantly improve the level of their integration.Moreover,development-oriented cultural consumption has a positive effect on the floating population’s integration and social participation,while entertainment-oriented cultural consumption facilitates their integration mainly by improving their sense of well-being.These findings could guide policymakers in developing targeted cultural consumption policies,implementing specific regional industry adjustments,and expanding domestic consumption demand. 展开更多
关键词 cultural consumption floating population urban integration social participation sense of well-being
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KCNQ1 rs2237895 gene polymorphism increases susceptibility to type 2 diabetes mellitus in Asian populations 被引量:1
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作者 Dong-Xu Li Li-Ping Yin +4 位作者 Yu-Qi Song Nan-Nan Shao Huan Zhu Chen-Sen He Jiang-Jie Sun 《World Journal of Diabetes》 SCIE 2024年第3期552-564,共13页
BACKGROUND The association of single nucleotide polymorphism of KCNQ1 gene rs2237895 with type 2 diabetes mellitus(T2DM)is currently controversial.It is unknown whether this association can be gene realized across dif... BACKGROUND The association of single nucleotide polymorphism of KCNQ1 gene rs2237895 with type 2 diabetes mellitus(T2DM)is currently controversial.It is unknown whether this association can be gene realized across different populations.AIM To determine the association of KCNQ1 rs2237895 with T2DM and provide reliable evidence for genetic susceptibility to T2DM.METHODS We searched PubMed,Embase,Web of Science,Cochrane Library,Medline,Baidu Academic,China National Knowledge Infrastructure,China Biomedical Literature Database,and Wanfang to investigate the association between KCNQ1 gene rs2237895 and the risk of T2DM up to January 12,2022.Review Manager 5.4 was used to analyze the association of the KCNQ1 gene rs2237895 polymorphism with T2DM and to evaluate the publication bias of the selected literature.RESULTS Twelve case–control studies(including 11273 cases and 11654 controls)met our inclusion criteria.In the full population,allelic model[odds ratio(OR):1.19;95%confidence interval(95%CI):1.09–1.29;P<0.0001],recessive model(OR:1.20;95%CI:1.11–1.29;P<0.0001),dominant model(OR:1.27.95%CI:1.14–1.42;P<0.0001),and codominant model(OR:1.36;95%CI:1.15–1.60;P=0.0003)(OR:1.22;95%CI:1.10–1.36;P=0.0002)indicated that the KCNQ1 gene rs2237895 polymorphism was significantly correlated with susceptibility to T2DM.In stratified analysis,this association was confirmed in Asian populations:allelic model(OR:1.25;95%CI:1.13–1.37;P<0.0001),recessive model(OR:1.29;95%CI:1.11–1.49;P=0.0007),dominant model(OR:1.35;95%CI:1.20–1.52;P<0.0001),codominant model(OR:1.49;95%CI:1.22–1.81;P<0.0001)(OR:1.26;95%CI:1.16–1.36;P<0.0001).In non-Asian populations,this association was not significant:Allelic model(OR:1.06,95%CI:0.98–1.14;P=0.12),recessive model(OR:1.04;95%CI:0.75–1.42;P=0.83),dominant model(OR:1.06;95%CI:0.98–1.15;P=0.15),codominant model(OR:1.08;95%CI:0.82–1.42;P=0.60.OR:1.15;95%CI:0.95–1.39;P=0.14).CONCLUSION KCNQ1 gene rs2237895 was significantly associated with susceptibility to T2DM in an Asian population.Carriers of the C allele had a higher risk of T2DM.This association was not significant in non-Asian populations. 展开更多
关键词 Type 2 diabetes mellitus KCNQ1 rs2237895 Single nucleotide polymorphism Asian populations
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Evaluating the performance of genomic selection on purebred population by incorporating crossbred data in pigs
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作者 Jun Zhou Qing Lin +10 位作者 Xueyan Feng Duanyang Ren Jinyan Teng Xibo Wu Dan Wu Xiaoke Zhang Xiaolong Yuan Zanmou Chen Jiaqi Li Zhe Zhang Hao Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期639-648,共10页
Genomic selection(GS)has been widely used in livestock,which greatly accelerated the genetic progress of complex traits.The population size was one of the significant factors affecting the prediction accuracy,while it... Genomic selection(GS)has been widely used in livestock,which greatly accelerated the genetic progress of complex traits.The population size was one of the significant factors affecting the prediction accuracy,while it was limited by the purebred population.Compared to directly combining two uncorrelated purebred populations to extend the reference population size,it might be more meaningful to incorporate the correlated crossbreds into reference population for genomic prediction.In this study,we simulated purebred offspring(PAS and PBS)and crossbred offspring(CAB)base on real genotype data of two base purebred populations(PA and PB),to evaluate the performance of genomic selection on purebred while incorporating crossbred information.The results showed that selecting key crossbred individuals via maximizing the expected genetic relationship(REL)was better than the other methods(individuals closet or farthest to the purebred population,CP/FP)in term of the prediction accuracy.Furthermore,the prediction accuracy of reference populations combining PA and CAB was significantly better only based on PA,which was similar to combine PA and PAS.Moreover,the rank correlation between the multiple of the increased relationship(MIR)and reliability improvement was 0.60-0.70.But for individuals with low correlation(Cor(Pi,PA or B),the reliability improvement was significantly lower than other individuals.Our findings suggested that incorporating crossbred into purebred population could improve the performance of genetic prediction compared with using the purebred population only.The genetic relationship between purebred and crossbred population is a key factor determining the increased reliability while incorporating crossbred population in the genomic prediction on pure bred individuals. 展开更多
关键词 PIGS crossbred population genomic selection reference population construction relationship
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Changes in the adult sex ratio of six duck species breeding populations over two decades
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作者 Monika Homolkova Petr Musil +4 位作者 Diego Pavon-Jordan Dorota Gajdosova Zuzana Musilova Sarka Neuzilova Jan Zouhar 《Avian Research》 SCIE CSCD 2024年第2期202-210,共9页
Despite all efforts,long-term changes in the adult sex ratios of breeding duck populations are still unclear;this uncertainty is especially true for male-bias populations,which are often under the scrutiny of research... Despite all efforts,long-term changes in the adult sex ratios of breeding duck populations are still unclear;this uncertainty is especially true for male-bias populations,which are often under the scrutiny of researchers lacking convenient results for the active protection of endangered species.Species with male-bias populations are usually strongly affected by a decline in population size that leads to a higher extinction risk.In this study,we examined our long-term data of the abundance of breeding populations in six duck species(Mallard Anas platyrhynchos,Gadwall Mareca strepera,Red-crested Pochard Netta rufina,Common Pochard Aythya ferina,Tufted Duck Aythya fuligula,and Common Goldeneye Bucephala clangula)from fishponds in South Bohemia,Czechia,between 2004 and 2022.This evidence was used to assess long-term changes in the adult sex ratio in these breeding populations and investigate the possible effects of the NAO index(North Atlantic Oscillation index)on them,indicating climate conditions in winter.We determined a long-term decrease of the proportion of females in the breeding season in two of the six examined species:Common Pochard and Red-crested Pochard,which is driven by the long-term increase in the number of males in contrast to the decreasing or stable number of females likely caused by different migration behaviours between females and males.In the case of Common Pochard,in breeding populations,we estimated 60-65%of males in the early 2000s rising to 75-80%in the early 2020s.However,we establish no significant effects linked to climate conditions of the previous winter in these species as a crucial cause of the changes of the proportion of females in the breeding population. 展开更多
关键词 Adult sex ratio Breeding population population dynamics Red-listed species WATERFOWL Winter weather conditions
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Multi Location Field Evaluation of BC1F2 Sorghum Populations for Striga Resistance in Niger
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作者 Ousseini Ardaly Abdou Aissata Mamadou Ibrahim +2 位作者 Yaw Eleblu John Saviour Ofori Kwadwo Ousmane Zakari Moussa 《American Journal of Plant Sciences》 CAS 2024年第10期1010-1021,共12页
In Niger, a landlocked country, sorghum is the second staple food cultivated over the country by smallholder farmer. The crop is important for human and animal consumption. Despite its importance, the crop is affected... In Niger, a landlocked country, sorghum is the second staple food cultivated over the country by smallholder farmer. The crop is important for human and animal consumption. Despite its importance, the crop is affected by biotic and abiotic constraints. Among those constraints, striga has a high impact on yield. In fact, to survive, farmers are growing their local preferred sorghum varieties wish is highly sensible to the weed. Striga management is a challenge that requires a permanent solution. In addition, the development of high-yielding Striga resistant genotypes will be appreciated by farmers. The development of striga resistance will be based on the breeding population performances under farmer’s diverse environmental conditions adaptation. The main objective of this study is to evaluate two breeding populations for striga resistance in two different environments at Boulke and Dibissou in Tahoua region, to identify the early and high-yielding striga tolerant genotypes under natural infestation. 展开更多
关键词 Striga Resistance SORGHUM Breeding population Multi Environment
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Evolution and Determinants of Population Agglomeration in Less Developed Metropolitan Areas:A Case Study of the Taiyuan Metropolitan Area,China
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作者 QIN Zhiqin LIANG Ye +1 位作者 AN Shuwei DOU Yongjing 《Chinese Geographical Science》 SCIE CSCD 2024年第4期739-751,共13页
It is of importance to enhance the urban areas'capacity for population aggregation in underdeveloped regions,aiming to rectify the imbalanced and insufficient pattern of economic development in China.Taking the Ta... It is of importance to enhance the urban areas'capacity for population aggregation in underdeveloped regions,aiming to rectify the imbalanced and insufficient pattern of economic development in China.Taking the Taiyuan Metropolitan Area(TMA)in central China as a case study,this paper examines the evolutionary process and characteristics of population agglomeration from 2000 to 2020,and identifies factors associated with agglomeration and their spatial effects.The findings indicated that:1)against the background of sustained population shrinkage in the provincial area,the TMA showed a demographic trend of steady increase,albeit with a decelerated growth rate.In the metropolitan area,urban population size continued to grow rapidly,whereas the rural areas endured sustained losses.Disparities in city size continued to widen,and the polarization of concentrated population in the core cities kept increasing.2)Agglomerations in both secondary and service industries had significant positive effects on local population agglomeration,with the former effect being stronger.Regional economic development,government fiscal expenditure,and financial advancement all contributed to facilitating local population clustering.From a spatial spillover perspective,service agglomeration and financial development promoted population agglomeration in surrounding areas.Conversely,fiscal expenditure inhibited such agglomeration.As for industrial agglomeration and regional economic development,their spatial spillover effects were non-significant.The results obtained reveal several policy implications aimed at enhancing the population agglomeration capacity of the metropolitan area in underdeveloped regions during the new era. 展开更多
关键词 population agglomeration population shrinkage spatial spillover effects Taiyuan Metropolitan Area(TMA) China
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Mercury Levels Assessment in the Population of Aby and Frambo Villages in the Vinicity of Aby Lagoon in Côte d’Ivoire (West Africa)
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作者 Stéphane Jean Claon Serge Kouakou Kouassi +4 位作者 Nina Laurette Ahouéfa Laurent Kipré Seri Arsène M’bassidjé Seka Joseph Allico Djaman Luc Kouakou Kouadio 《Journal of Water Resource and Protection》 CAS 2024年第3期219-232,共14页
The Minamata Convention in the aim to protect human life and the environment, seeks to reduce mercury (Hg) by monitoring it concentrations in the environment. Artisanal and Small-scale Gold Mining (ASGM) has been iden... The Minamata Convention in the aim to protect human life and the environment, seeks to reduce mercury (Hg) by monitoring it concentrations in the environment. Artisanal and Small-scale Gold Mining (ASGM) has been identified as the most important anthropogenic source of human exposure to Hg. In this context, the main goal of this study was to assess the level of mercury in hair of two (2) populations living along two lagoons respectively Aby and Tendo, in Ivory Coast. To reach this goal, hair samples of 138 residents were collected and analyzed by using Cold Vapor Atomic Fluorescence Spectrophotometry (CV-AFS) technique for mercury concentration. Results showed that for the entire population the Hg mean was 2.34 μg/g. Also, they were ranged between 0.15 to 8.53 μg/g and presented substantial differences amongst the villages. In Aby village, we observed the highest Hg concentrations (Mean = 2.62 μg/g). Our findings showed that almost the entire sample group (82%) exceed the USEPA recommended limit, furthermore 56% of them exceed the normal level of WHO and 2% of the respondent has the unhealthy levels of mercury (≥6 μg Hg/g) of hair by WHO standards. Gender differences in hair mercury varies greatly among reports. Lower levels in women’s hair compared to men were reported in the both village. Considering age, the lowest concentrations were observed with children. However, when we take in account the age groups, data suggested that the most exposed sub-population of [18-29] years old is from Aby village in opposite at Frambo village, the same case those who were ≥ 40 years old. It’s convenient to note that, the proportion of Mercury levels would not to be neglected among studied population especially with the resident from Aby village. So, some measures need to be taken at the political level to control mercury contamination. 展开更多
关键词 MERCURY HAIR ASGM population Exposure Côte d’Ivoire
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Floating periodic pontoons for broad bandgaps of water waves
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作者 Huaqing JIN Haicheng ZHANG +1 位作者 Ye LU Daolin XU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第11期1913-1928,共16页
The narrow attenuation bands of traditional marine structures have long been a challenge in mitigating water waves.In this paper,a metastructure(MS)composed of floating periodic pontoons is proposed for broadband wate... The narrow attenuation bands of traditional marine structures have long been a challenge in mitigating water waves.In this paper,a metastructure(MS)composed of floating periodic pontoons is proposed for broadband water wave attenuation.The interaction of surface gravity waves with the MS is investigated using linear wave theory.The potential solutions of water waves by the MS with a finite array are developed by using the eigenfunction expansion matching method(EEMM),and the band structure of the MS is calculated by the transfer matrix method(TMM),in which the evanescent modes of waves are considered.The solution is verified against the existing numerical result for a special case.Based on the present solution,the association between Bragg resonance reflection and Bloch bandgaps is examined,the effects of pontoon geometry are analyzed,and the comparison between floating MS and bottom-mounted periodic structures is conducted.A computational fluid dynamics(CFD)model is further developed to assess the structures in practical fluid environments,and the floating MS presents excellent wave attenuation performance.The study presented here may provide a promising solution for protecting the coast and offshore structures. 展开更多
关键词 floating metastructure(MS) wave attenuation bandgap analytical method
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Comparative Study of Genetic Structure and Genetic Diversity betweenWild and Cultivated Populations of Taxus cuspidata,Northeast China
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作者 Dandan Wang Xiaohong Li Yanwen Zhang 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第2期355-369,共15页
Taxus cuspidata is a rare plant with important medicinal and ornamental value.Aiming at the obvious differences between wild and cultivated populations of T.cuspidata from Northeast China,a total of 61 samples,that is... Taxus cuspidata is a rare plant with important medicinal and ornamental value.Aiming at the obvious differences between wild and cultivated populations of T.cuspidata from Northeast China,a total of 61 samples,that is,33 wild yews and 28 cultivated yews were used to analyze the differences and correlations of the kinship,genetic diversity,and genetic structure between them by specific length amplified fragment sequencing(SLAF-seq).Finally,470725 polymorphic SLAF tags and 58622 valid SNP markers were obtained.Phylogenetic analysis showed that 61 samples were classified into 2 clusters:wild populations and cultivated populations,and some wild yews were categorized into the cultivated populations;the genetic diversity analysis showed that the Nei diversity index of wild populations(0.4068)was smaller than that of cultivated populations(0.4414),and the polymorphic information content(PIC)of wild populations(0.2861)was smaller than that of cultivated populations(0.3309).The genetic differentiation analysis showed that the total populations of gene diversity(H_(t))of cultivated and wild populations were respectively 0.8159 and 0.5685,the coefficient of gene differentiation(G_(st))of cultivated and wild populations was respectively 0.3021 and 0.1068,and the gene flow(N_(m))(2.4967)of wild populations was larger than cultivated populations(0.8199).The molecular variance(AMOVA)revealed that inter-population variation accounted for 29.57%of the total genetic variation,while intra-population variation accounted for 70.42% of the total genetic variation(p<0.001),this suggested that the genetic variation in the T.cuspidata is mainly attributed to within-population factors.In conclusion,the genetic distance between geographical ecological groups of wild populations was generally smaller than that of cultivated populations,and the degree of genetic diversity and genetic differentiation was smaller than that of cultivated populations.As evident,the utilization of SLAF-seq technology enables efficient and accurate development of SNP markers suitable for genetic analysis of T.cuspidata species.These developed SNP markers can provide a molecular foundation for T.cuspidata breeding,construction of genetic maps,variety identification,and association analysis of agronomic traits. 展开更多
关键词 T.cuspidata SLAF-seq SNP wild population cultivated population genetic structure
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Land-population-industry based village evolution and its influencing factors in the upper Tuojiang River
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作者 ZHAN Yunjun JI Yuxin +2 位作者 HUANG Jiejun MA Changying MA Chuanqi 《Journal of Mountain Science》 SCIE CSCD 2024年第8期2790-2809,共20页
With economic development and urbanization in China,the rural settlements have experienced great change.To explore the evolution process of rural settlements in terms of land,population and industry can reveal the dev... With economic development and urbanization in China,the rural settlements have experienced great change.To explore the evolution process of rural settlements in terms of land,population and industry can reveal the development law of rural spatial distribution,population structure and industrial economy in different stages and regions.Studying the development status and evolution characteristics of villages in the upper Tuojiang River basin in Southwest China in the past 20 years are of significant value.The upper Tuojiang River basin includes the main types of terrain found in the Southwest region:mountainous,plains,and hills,exhibiting a certain typicality of geographical characteristics.This study took towns and townships at the town-level scale as the basic unit of research,and constructed an evaluation system for village evolution based on'land,population,and industry'.It employed Criteria Importance Through Inter-Criteria Correlation(CRITIC)analysis to examine the characteristics of village evolution in the area from 2000 to 2020,and used geographic detector analysis to identify the leading factors affecting village evolution.The results show that:(1)From 2000 to 2010,villages in the upper Tuojiang River basin experienced significant changes,and the pace of these transformations slowed from 2010 to 2020.(2)From a comprehensive perspective,from 2000 to 2020,villages in hilly areas show a decline,while villages in plain areas near the city center show a positive urbanization development.(3)Road accessibility and distance from the city center are the main factors that explain the spatial differentiation of village evolution degree in the study area.This study elucidates the spatiotemporal evolution characteristics of villages in the upper Tuojiang River basin and identifies the primary factors contributing to their changes,which will provide a reference for investigating the development of rural areas in different terrains of Southwest China. 展开更多
关键词 Village evolution LAND population Industry Geographic detector
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Global Dynamic Responses and Progressive Failure of Submerged Floating Tunnel Under Cable Breakage Conditions
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作者 ZHOU Xiang-bo QIAO Dong-sheng +3 位作者 WANG Ming TANG Guo-qiang LU Lin OU Jinping 《China Ocean Engineering》 SCIE EI CSCD 2024年第4期676-688,共13页
The Submerged Floating Tunnel(SFT)relies on a tensioned mooring system for precise positioning.The sudden breakage of a single cable can trigger an immediate alteration in the constraint conditions of the tube,inducin... The Submerged Floating Tunnel(SFT)relies on a tensioned mooring system for precise positioning.The sudden breakage of a single cable can trigger an immediate alteration in the constraint conditions of the tube,inducing a transient heave response within the structure along with a transient increase in cable tension experienced by adjacent cables.In more severe cases,this may even lead to a progressive failure culminating in the global destruction of the SFT.This study used ANSYS/AQWA to establish a numerical model of the entire length SFT for the hydrodynamic response analysis,and conducted a coupled calculation of the dynamic responses of the SFT-mooring line model based on Orca Flex to study the global dynamic responses of the SFT at the moment of cable breakage and the redistribution of cable internal forces.The most unfavorable position for SFT cable breakage was identified,the influence mechanism of cable breakage at different positions on the global dynamic response was revealed,and the progressive chain failure pattern caused by localized cable breakage are also clarified. 展开更多
关键词 submerged floating tunnel cable breakage global dynamic responses progressive failure
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Heterogeneous population distribution enhances resistance to wheat lodging by optimizing the light environment
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作者 Yibo Hu Feng Qin +6 位作者 Zhen Wu Xiaoqin Wang Xiaolong Ren Zhikuan Jia Zhenlin Wang Xiaoguang Chen Tie Cai 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第7期2211-2226,共16页
Lodging is still the key factor that limits continuous increases in wheat yields today,because the mechanical strength of culms is reduced due to low-light stress in populations under high-yield cultivation.The mechan... Lodging is still the key factor that limits continuous increases in wheat yields today,because the mechanical strength of culms is reduced due to low-light stress in populations under high-yield cultivation.The mechanical properties of the culm are mainly determined by lignin,which is affected by the light environment.However,little is known about whether the light environment can be sufficiently improved by changing the population distribution to inhibit culm lodging.Therefore,in this study,we used the wheat cultivar“Xinong 979”to establish a low-density homogeneous distribution treatment(LD),high-density homogeneous distribution treatment(HD),and high-density heterogeneous distribution treatment(HD-h)to study the regulatory effects and mechanism responsible for differences in the lodging resistance of wheat culms under different population distributions.Compared with LD,HD significantly reduced the light transmittance in the middle and basal layers of the canopy,the net photosynthetic rate in the middle and lower leaves of plants,the accumulation of lignin in the culm,and the breaking resistance of the culm,and thus the lodging index values increased significantly,with lodging rates of 67.5%in 2020–2021 and 59.3%in 2021–2022.Under HD-h,the light transmittance and other indicators in the middle and basal canopy layers were significantly higher than those under HD,and the lodging index decreased to the point that no lodging occurred.Compared with LD,the activities of phenylalanine ammonia-Lyase(PAL),4-coumarate:coenzyme A ligase(4CL),catechol-O-methyltransferase(COMT),and cinnamyl-alcohol dehydrogenase(CAD)in the lignin synthesis pathway were significantly reduced in the culms under HD during the critical period for culm formation,and the relative expression levels of TaPAL,Ta4CL,TaCOMT,and TaCAD were significantly downregulated.However,the activities of lignin synthesis-related enzymes and their gene expression levels were significantly increased under HD-h compared with HD.A partial least squares path modeling analysis found significant positive effects between the canopy light environment,the photosynthetic capacity of the middle and lower leaves of plants,lignin synthesis and accumulation,and lodging resistance in the culms.Thus,under conventional high-density planting,the risk of wheat lodging was significantly higher.Accordingly,the canopy light environment can be optimized by changing the heterogeneity of the population distribution to improve the photosynthetic capacity of the middle and lower leaves of plants,promote lignin accumulation in the culm,and enhance lodging resistance in wheat.These findings provide a basis for understanding the mechanism responsible for the lower mechanical strength of the culm under high-yield wheat cultivation,and a theoretical basis and for developing technical measures to enhance lodging resistance. 展开更多
关键词 canopy light environment LIGNIN LODGING population distribution WHEAT
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Simulation of wave scattering over a floating platform in the ocean with a coupled CFD-IBM model
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作者 Pengxuan Luo Jingxin Zhang +1 位作者 Yongyong Cao Shaohong Song 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第3期157-161,共5页
A numerical study of linear wave scattering over a floating platform has been simulated by an efficient numericalmodel in this letter.The non-hydrostatic model is used to simulate the free surface and the uneven botto... A numerical study of linear wave scattering over a floating platform has been simulated by an efficient numericalmodel in this letter.The non-hydrostatic model is used to simulate the free surface and the uneven bottom.For thesolid body modelling,the immersed boundary method(IBM)is implemented by introducing a virtual boundaryforce into the momentum equations to emulate the boundary conditions.This implementation enhances theability of the model to simulate interactions between waves and floating structures.A numerical case involvingwave interactions with a floating platform is studied to validate the numerical model.By simulating the wavepropagation,the numerical model captures the variation of the wave scattering very well,which verifies theperformance of the numerical model and the robust strategy of the IBM. 展开更多
关键词 Non-hydrostatic model Immersed boundary method Wave structure interaction floating platform
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Experimental Study on Hydrodynamic Load Characteristics for A Typical Cross-Section of A Submerged Floating Tunnel
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作者 ZHANG Hong-qian YANG Zhi-wen +2 位作者 LI Shao-wu YUAN Chun-guang ZHANG Hua-qing 《China Ocean Engineering》 SCIE EI CSCD 2024年第5期893-903,共11页
The typical cross-sectional form of a submerged floating tunnel plays a significant role in the dynamic response of the tunnel itself,which directly affects the overall design.In this work,a series of experiments invo... The typical cross-sectional form of a submerged floating tunnel plays a significant role in the dynamic response of the tunnel itself,which directly affects the overall design.In this work,a series of experiments involving wave action on a submerged floating tube cross section is reported to study its hydrodynamic load characteristics.Two typical cross section tube cylinders,circular and rectangular,are chosen.Experiments are carried out in a wave flume with waves of relatively low Keulegan-Carpenter(KC)numbers.Three relative depths of submergence of 0,0.25 and 0.5 are chosen.The measured wave forces in regular waves are used to analyze the horizontal force,vertical force and torque,and then the drag coefficient(Cd)and inertia coefficient(Cm)are derived.The results show that the drag coefficients at low KC numbers are large and decrease sharply with increasing KC number.The inertial coefficient Cm values in the vertical direction are about 70%larger than those in the horizontal direction.With an increase in aspect ratio(the ratio of the height to width of the structure),the ratio of inertia coefficient in the horizontal direction to that in the vertical direction increases remarkably.The inertia force coefficient is very sensitive to the submerged water depth and aspect ratio.The existing results may overestimate the actual force value. 展开更多
关键词 submerged floating tunnel tube cylinder wave force coefficient physical experiments
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Numerical Study on the Effect of Gap Diffraction on the Hydrodynamic Performance of A Floating Breakwater
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作者 BIAN Xiang-qian JI Chun-yan +2 位作者 XU Sheng GUO Jian-ting HUO Fa-li 《China Ocean Engineering》 SCIE EI CSCD 2024年第4期663-675,共13页
Two-dimensional(2D)flume experiments are useful in investigating the performances of floating breakwaters(FBs),including hydrodynamic performances,motion responses,and mooring forces.Designing a reasonable gap between... Two-dimensional(2D)flume experiments are useful in investigating the performances of floating breakwaters(FBs),including hydrodynamic performances,motion responses,and mooring forces.Designing a reasonable gap between the flume wall and the FBs is a critical step in 2D flume tests.However,research on the effect of the gap on the accuracy of 2D FB experimental results is scarce.To address this issue,a numerical wave tank is developed using CFD to estimate the wave-FB interaction of a moored dual-cylindrical FB,and the results are compared to experimental data from a previously published work.There is good agreement between them,indicating that the numerical model is sufficiently accurate.The numerical model is then applied to explore the effect of gap diffraction on the performance of FBs in2D experiments.It was discovered that the nondimensional gap length L_(Gap)/W_(Pool)should be smaller than 7.5%to ensure that the relative error of the transmission coefficient is smaller than 3%.The influence of the gap is also related to the entering wave properties,such as the wave height and period. 展开更多
关键词 floating breakwater diffraction effect GAP hydrodynamic performance model experiments CFD numerical simulation
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Epidemiological, Clinical Aspects and Factors Associated with Typical Gastroesophageal Reflux Disease in the General Population of Parakou, Republic of Benin
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作者 Saké Khadidjatou Tamou Sambo Bio Elie +3 位作者 Zinsou Jocelyne Abla Dovonou Comlan Albert Sehonou Jean Kodjoh Nicolas 《Open Journal of Gastroenterology》 CAS 2024年第2期41-58,共18页
Introduction: Gastroesophageal reflux disease (GERD) is a benign and chronic disease that can impair the quality of life. Objective: To study the epidemiological, clinical aspects and factors associated with typical G... Introduction: Gastroesophageal reflux disease (GERD) is a benign and chronic disease that can impair the quality of life. Objective: To study the epidemiological, clinical aspects and factors associated with typical GERD in the general population of Parakou in the Republic of Benin. Methods: This was a descriptive and analytical cross-sectional study with prospective data collection which took place from May 1, 2019 to June 30, 2019. The study population consisted of any subject aged at least 15 years and living in Parakou. Subjects aged at least 15 years, present on the day of the survey and having given their free and informed verbal consent were included. The Short form of QRS®(Reflux-Qual Short form) questionnaire and the “Hospital Anxiety and Depression” score were used to assess the quality of life and anxiety/depression, respectively. The sampling was probabilistic through a 2-stage cluster sampling. The variable of interest was the presence of GERD. Results: Out of 390 subjects surveyed, 28 had symptoms of typical GERD, representing a prevalence of 7.18%. The average age of these subjects was 27.11 ± 7.88 years. Fifteen subjects (53.57%) were male, giving a sex ratio of 1.15. Fourteen (50%) had a secondary level of education, 12 (42.86%) were pupils/students, 18 (64.29%) were single. The monthly income of 22 subjects (78.57%) was lower than the guaranteed interprofessional minimum wage (40,000 FCFA). The average duration of progression of symptoms was 15.89 ± 4.97 months. Symptoms occurred less than twice a week in 22 subjects (78.57%). The clinical manifestations were both diurnal and nocturnal in 12 subjects (42.86%). None of the 28 subjects with GERD had clinical warning signs. Asthma, diabetes, consumption of high fat or spice foods, carbonated drinks, non-steroidal anti-inflammatory drugs, alcoholic beverages and tobacco were statistically associated with the occurrence of GERD. Each of the 28 subjects had at least one associated factor. A significant impair in quality of life was observed in 27 patients (96.43%). Conclusion: Typical GERD is relatively common in the general population of Parakou in the Republic of Benin. It often affects young males. Among the risk factors identified, the most common are carbonated drinks, spicy meals and diabetes. GERD significantly impairs quality of life. Raising awareness about the disease and its associated factors is necessary among the general population. 展开更多
关键词 Gastroesophageal Reflux Disease EPIDEMIOLOGY General population Associated Factors Quality of Life Parakou
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Theoretical investigations of population trapping phenomena in atomic four-color,three-step photoionization scheme
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作者 卢肖勇 孙亚鹏 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期333-340,共8页
The four-color three-step selective photoionization process of atom is very important in laser isotope separation technology.The population trapping phenomena and their influences are studied theoretically in monochro... The four-color three-step selective photoionization process of atom is very important in laser isotope separation technology.The population trapping phenomena and their influences are studied theoretically in monochromatic and non-monochromatic laser fields based on the density matrix theory in this work.Time evolutions of the photoionization properties of the four-color,three-step process are given.The population trapping effects occur intensely in monochromatic excitation,while it gradually turns weak as the laser bandwidth increases.The effects of bandwidth,Rabi frequency,time delay,and frequency detuning on the population trapping effect are investigated in monochromatic and non-monochromatic laser fields.The effects of laser process parameters and atomic parameters on the effective selective photoionization are also discussed.The ionization probability and selectivity factors,as evaluation indexes,are difficult to improve synchronously by adjusting systematic parameters.Besides,the existence of metastable state may play a negative role when its population is low enough. 展开更多
关键词 population trapping metastable state selective photoionization laser bandwidth
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Profiling of the Retrospective Epidemiology of the Human Papillomavirus and Related Cancers in the United Arab Emirates Population
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作者 Ihsan Mahasneh Berjas Abumusimir +2 位作者 Mustapha Enaji Ikram Taibi Ferdos Ebrahim 《Journal of Biosciences and Medicines》 2024年第10期1-9,共9页
The human papillomavirus (HPV) is a leading cause of infectious cancers, leading to a growing global interest on the profiling of HPV-related cancers. Therefore, the aim of the study was to determine the retrospective... The human papillomavirus (HPV) is a leading cause of infectious cancers, leading to a growing global interest on the profiling of HPV-related cancers. Therefore, the aim of the study was to determine the retrospective epidemiological profile of HPV-related cancer in the United Arab Emirates (UAE). The incidence profiling of HPV-related cancers in males and females of UAE of all ages ranged from a minimum of 0.6% to a maximum of 4.5% for testes cancer and colon cancer respectively in males;whilst in females it ranged from a minimum of 1.0% and a maximum of 34% for Hodgkin lymphoma, kidney, bladder, liver and pancreas cancer and breast cancer, respectively. The incidence profiling of HPV-related cancers in males and females of ages 15 - 44 years old ranged from a minimum of 0.1% to a maximum of 11.2% for pancreas cancer, and colon and rectum cancer respectively in males, whilst in females it ranged from a minimum of 0.1% and a maximum of 18% for pancreas and breast cancer, respectively. The mortality profiling of HPV-related cancers in males and females of all ages in the UAE ranged from a minimum of 0.1% for Hodgkin lymphoma and testicular cancer to a maximum of 4.5% for colon and rectum cancer respectively in males, whilst in females it ranged from a minimum of 0.2% and a maximum of 4.5% for pancreas and breast cancer, respectively. The mortality profiling of HPV-related cancers mortality in males and females of ages 15 - 44 years old in the UAE ranged from a minimum of 0.2% to a maximum of 4.3% for testicular cancer and colon cancer respectively in males, whilst in females it ranged from a minimum of 0.2% and a maximum of 7.2% for bladder and breast cancer respectively. In conclusion, the profiling of HPV-related cancers in UAE for both males and females of all ages is similar to that reported for other parts of the world. 展开更多
关键词 HPV EPIDEMIOLOGY UAE population
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Evaluation and Projection of Population Exposure to Temperature Extremes over the Beijing−Tianjin−Hebei Region Using a High-Resolution Regional Climate Model RegCM4 Ensemble
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作者 Peihua QIN Zhenghui XIE +1 位作者 Rui HAN Buchun LIU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1132-1146,共15页
Temperature extremes over rapidly urbanizing regions with high population densities have been scrutinized due to their severe impacts on human safety and economics.First of all,the performance of the regional climate ... Temperature extremes over rapidly urbanizing regions with high population densities have been scrutinized due to their severe impacts on human safety and economics.First of all,the performance of the regional climate model RegCM4 with a hydrostatic or non-hydrostatic dynamic core in simulating seasonal temperature and temperature extremes was evaluated over the historical period of 1991–99 at a 12-km spatial resolution over China and a 3-km resolution over the Beijing−Tianjin−Hebei(JJJ)region,a typical urban agglomeration of China.Simulations of spatial distributions of temperature extremes over the JJJ region using RegCM4 with hydrostatic and non-hydrostatic cores showed high spatial correlations of more than 0.8 with the observations.Under a warming climate,temperature extremes of annual maximum daily temperature(TXx)and summer days(SU)in China and the JJJ region showed obvious increases by the end of the 21st century while there was a general reduction in frost days(FD).The ensemble of RegCM4 with different land surface components was used to examine population exposure to temperature extremes over the JJJ region.Population exposure to temperature extremes was found to decrease in 2091−99 relative to 1991−99 over the majority of the JJJ region due to the joint impacts of increases in temperature extremes over the JJJ and population decreases over the JJJ region,except for downtown areas.Furthermore,changes in population exposure to temperature extremes were mainly dominated by future population changes.Finally,we quantified changes in exposure to temperature extremes with temperature increase over the JJJ region.This study helps to provide relevant policies to respond future climate risks over the JJJ region. 展开更多
关键词 CMIP6 convection-permitting population exposure RegCM4 temperature extremes
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