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Ecological Dynamics of a Logistic Population Model with Impulsive Age-selective Harvesting
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作者 DAI Xiangjun JIAO Jianjun 《应用数学》 北大核心 2026年第1期72-79,共8页
In this paper,we establish and study a single-species logistic model with impulsive age-selective harvesting.First,we prove the ultimate boundedness of the solutions of the system.Then,we obtain conditions for the asy... In this paper,we establish and study a single-species logistic model with impulsive age-selective harvesting.First,we prove the ultimate boundedness of the solutions of the system.Then,we obtain conditions for the asymptotic stability of the trivial solution and the positive periodic solution.Finally,numerical simulations are presented to validate our results.Our results show that age-selective harvesting is more conducive to sustainable population survival than non-age-selective harvesting. 展开更多
关键词 The logistic population model Selective harvesting Asymptotic stability EXTINCTION
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Coronal plane alignment of the knee phenotypes and ankle joint coronal plane alignment patterns in Egyptian population
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作者 Ahmed A Khalifa Mohamed Moustafa +3 位作者 Shikuria Lemma Mostafa Fayez Ahmed M Abdelaal Amr A Fadle 《World Journal of Orthopedics》 2026年第1期67-80,共14页
BACKGROUND In an era leaning toward a personalized alignment of total knee arthroplasty,coronal plane alignment of the knee(CPAK)phenotypes for each population are studied;furthermore,other possible variables affectin... BACKGROUND In an era leaning toward a personalized alignment of total knee arthroplasty,coronal plane alignment of the knee(CPAK)phenotypes for each population are studied;furthermore,other possible variables affecting the alignment,such as ankle joint alignment,should be considered.AIM To determine CPAK distribution in the North African(Egyptian)population with knee osteoarthritis and to assess ankle joint line orientation(AJLO)adaptations across different CPAK types.METHODS A cross-sectional study was conducted on patients with primary knee osteoarthritis and normal ankle joints.Radiographic parameters included the mechanical lateral distal femoral angle,medial proximal tibial angle,and the derived calculations of joint line obliquity(JLO)and arithmetic hip-knee-ankle angle(aHKA).The tibial plafond horizontal angle(TPHA)was used for AJLO assessment,where 0°is neutral(type N),<0°is varus(type A),and>0°is valgus(type B).The nine CPAK types were further divided into 27 subtypes after incorporating the three AJLO types.RESULTS A total of 527 patients(1054 knees)were included for CPAK classification,and 435 patients(870 knees and ankles)for AJLO assessment.The mean age was 57.2±7.8 years,with 79.5%females.Most knees(76.4%)demonstrated varus alignment(mean aHKA was-5.51°±4.84°)and apex distal JLO(55.3%)(mean JLO was 176.43°±4.53°).CPAK types I(44.3%),IV(28.6%),and II(10%)were the most common.Regarding AJLO,70.2%of ankles exhibited varus orientation(mean TPHA was-5.21°±6.45°).The most frequent combined subtypes were CPAK type I-A(33.7%),IV-A(21.5%),and I-N(6.9%).A significant positive correlation was found between the TPHA and aHKA(r=0.40,P<0.001).CONCLUSION In this North African cohort,varus knee alignment with apex distal JLO and varus AJLO predominated.CPAK types I,IV,and II were the most common types,while subtypes I-A,IV-A,and I-N were commonly occurring after incorporating AJLO types;furthermore,the AJLO was significantly correlated to aHKA. 展开更多
关键词 Coronal plane alignment of the knee classification Coronal alignment Ankle joint alignment Knee arthroplasty Knee replacement North African population
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Comparative Study of the Malthusian Population Model and the Logistic Population Model for Bangladesh
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作者 Md. Showkat Akber Khandoker Nasrin Ismet Ara Md. Sabbir Alam 《Applied Mathematics》 2025年第2期169-182,共14页
Bangladesh has a denser population in comparison with many other countries. Though the rate of population increase has been regarded as a concerning issue, estimation of the population instability in the upcoming year... Bangladesh has a denser population in comparison with many other countries. Though the rate of population increase has been regarded as a concerning issue, estimation of the population instability in the upcoming years may be useful for national planning. To predict Bangladesh’s future population, this study compares the estimated populations of two popular population models, the Malthusian and the logistic population models, with the country’s census population published by BBS. We also tried to find out which model gives a better approximation for forecasting the past, present, and future population between these two models. 展开更多
关键词 Malthusian population Model Logistic population Model population Growth Carrying Capacity
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Balancing Blue and Gray The marine economy continues to expand even as the aging population reshapes labor markets and consumer trends,calling for innovation and adaptive policies to sustain growth
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作者 Luo Weijie 《China Report ASEAN》 2025年第11期34-35,共2页
The marine economy has emerged as a vital driver of economic growth in both China and ASEAN countries.It encompasses a wide range of activities including fisheries,maritime transport,offshore oil and gas exploration,a... The marine economy has emerged as a vital driver of economic growth in both China and ASEAN countries.It encompasses a wide range of activities including fisheries,maritime transport,offshore oil and gas exploration,and marine tourism.At the same time,demographic structures are undergoing notable changes,with an increasing share of the older population.This trend of population aging has profound implications for various sectors,including the marine economy.Understanding the interplay between these dynamics is essential for sustainable development and policy-making. 展开更多
关键词 economic growth marine economy consumer trends population aging adaptive policies aging population labor markets INNOVATION
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Angular-Momentum-Resolved Rydberg State Population of Argon Ions in Strong Laser Fields
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作者 Zhigang Zheng Di Wang +6 位作者 Mingyue Wang Li Wang Xu Sun Jing Zhao Zhihui Lv Xiaowei Wang Zengxiu Zhao 《Chinese Physics Letters》 2025年第5期21-25,共5页
This letter demonstrates an experimental approach to measuring the angular-momentum-resolved population of excited states in laser-produced argon ions.By measuring the spectra of free induction decay emissions corresp... This letter demonstrates an experimental approach to measuring the angular-momentum-resolved population of excited states in laser-produced argon ions.By measuring the spectra of free induction decay emissions corresponding to the resonant transitions between Rydberg states,the relative population of the Rydberg states is obtained with known Einstein A-coefficients.This study deepens the mechanistic understanding of coherent dynamics in laser-driven ionic excited states,and establishes experimental benchmarks essential for validating and refining advanced quantum kinetic models in strong-field physics. 展开更多
关键词 coherent dynamics strong laser fields rydberg statesthe relative population rydberg states resonant transitions free induction decay emissions angular momentum resolved rydberg state population
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National Population Health Data Center
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《Chinese Medical Sciences Journal》 2025年第1期F0003-F0003,共1页
National Population Health Data Center(NPHDC)is one of China's 20 national-level science data centers,jointly designated by the Ministry of Science and Technology and the Ministry of Finance.Operated by the Chines... National Population Health Data Center(NPHDC)is one of China's 20 national-level science data centers,jointly designated by the Ministry of Science and Technology and the Ministry of Finance.Operated by the Chinese Academy of Medical Sciences under the oversight of the National Health Commission,NPHDC adheres to national regulations including the Scientific Data Management Measures and the National Science and Technology Infrastructure Service Platform Management Measures,and is committed to collecting,integrating,managing,and sharing biomedical and health data through openaccess platform,fostering open sharing and engaging in international cooperation. 展开更多
关键词 science technology infrastructure population health data open access international cooperation national population health data center scientific data management biomedical data health data
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Classification of densities and characteristics of curve of population centers in China by GIS 被引量:4
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作者 GE Meiling FENG Zhiming 《Journal of Geographical Sciences》 SCIE CSCD 2010年第4期628-640,共13页
In this paper, with the spatial analysis functions in ArcGIS and the county-level census data of 2000 in China, the population density map was divided and shown by classes, meanwhile, the map system of population dist... In this paper, with the spatial analysis functions in ArcGIS and the county-level census data of 2000 in China, the population density map was divided and shown by classes, meanwhile, the map system of population distribution and a curve of population centers were formed; in accordance with the geographical proximity principle, the classes of population densities were reclassified and a population density map was obtained which had the spatial clustering characteristic. The multi-layer superposition based on the population density classification shows that the population densities become denser from the Northwest to the Southeast; the multi-layer clustering phenomenon of the Chinese population distribution is obvious, the populations have a water-based characteristic gathering towards the rivers and coastlines. The curve of population centers shows the population densities transit from the high density region to the low one on the whole, while in low-density areas there are relatively dense areas, and in high-density areas there are relatively sparse areas. The reclassification research on the population density map based on the curve of population centers shows that the Chinese population densities can be divided into 9 classes, hereby, the geographical distribution of Chinese population can be divided into 9 type regions: the concentration core zone, high concentration zone, moderate concentration zone, low concentration zone, general transitional zone, relatively sparse area, absolute sparse area, extreme sparse area, and basic no-man's land. More than 3/4 of the population of China is concentrated in less than 1/5 of the land area, and more than half of the land area is inhabited by less than 2% of the population, the result reveals a better space law of China's population distribution. 展开更多
关键词 population population density population gravity curve of population centers GIS
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Seasonal population trend and relative occurrence of pests and their natural enemies among cotton species and cultivars in India 被引量:1
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作者 NAGRARE V.S. NAIKWADI Bhausaheb +4 位作者 FAND Babasaheb B. NAIK V.Chinna Babu TENGURI Prabhulinga GOKTE‑NARKHEDKAR Nandini WAGHMARE V.N. 《Journal of Cotton Research》 2025年第2期178-192,共15页
Background Cotton crop is infested by numerous arthropod pests from sowing to harvesting,causing substantial direct and indirect yield losses.Knowledge of seasonal population trends and the relative occurrence of pest... Background Cotton crop is infested by numerous arthropod pests from sowing to harvesting,causing substantial direct and indirect yield losses.Knowledge of seasonal population trends and the relative occurrence of pests and their natural enemies is required to minimize the pest population and yield losses.In the current study,analysis of the seasonal population trend of pests and natural enemies and their relative occurrence on cultivars of three cotton species in Central India has been carried out.Results A higher number and diversity of sucking pests were observed during the vegetative cotton growth stage(60 days after sowing),declining as the crop matured.With the exception of cotton jassid(Amrasca biguttula biguttula Ishida),which caused significant crop damage mainly from August to September;populations of other sucking insects seldom reached economic threshold levels(ETL)throughout the studied period.The bollworm complex populations were minimal,except for the pink bollworm(Pectinophora gossypiella Saunders),which re-emerged as a menace to cotton crops during the cotton cropping season 2017–2018 due to resistance development against Bt-cotton.A reasonably good number of predatory arthropods,including coccinellids,lacewings,and spiders,were found actively preying on the arthropod pest complex of the cotton crop during the early vegetative growth stage.Linear regression indicates a significant relationship between green boll infestations and pink bollworm moths in pheromone traps.Multiple linear regression analyse showed mean weekly weather at one-or two-week lag periods had a significant impact on sucking pest population(cotton aphid,cotton jassid,cotton whitefly,and onion thrips)fluctuation.Gossypium hirsutum cultivars RCH 2 and DCH 32,and G.barbadense cultivar Suvin were found susceptible to cotton jassid and onion thrips.Phule Dhanvantary,an G.arboreum cotton cultivar,demonstrated the highest tolerance among all evaluated cultivars against all sucking pests.Conclusion These findings have important implications for pest management in cotton crops.Susceptible cultivars warrant more attention for plant protection measures,making them more input-intensive.The choice of appropriate cultivars can help minimize input costs,thereby increasing net returns for cotton farmers. 展开更多
关键词 COTTON PESTS population trend Relative occurrence CULTIVARS Natural enemies
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Demographic trends in mortality with older population due to atrial fibrillation and flutter from 1999-2020 被引量:1
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作者 Mahnoor Sukaina Marium Waheed +2 位作者 Shafi Rehman Md Al Hasibuzzaman Rabab Meghani 《World Journal of Cardiology》 2025年第1期1-7,共7页
Atrial fibrillation(AF)/atrial flutter(AFL)is the most common sustained cardiac arrhythmia.The known risk factors for developing AF/AFL include age,structural heart disease,hypertension,diabetes mellitus,or hyperthyro... Atrial fibrillation(AF)/atrial flutter(AFL)is the most common sustained cardiac arrhythmia.The known risk factors for developing AF/AFL include age,structural heart disease,hypertension,diabetes mellitus,or hyperthyroidism.This study aims to attribute the trends in AF/AFL-related mortalities over the past two decades 1999-2020 concerning race and sex and disparity among them.To the best of our knowledge,this is the first study that estimates the trends and mortality due to AF/AFL from 1999-2020 in older adults in the United States.In this 21-year analysis of mortality data,we found a constant increase in mortality rates due to AF/AFL in older adults.From 1999 to 2020,the overall mortality in older adults aged 65 and above,regardless of sex and race,is found to be almost doubled i.e.about a 50.2%increase in the number of deaths due to AF/AFL.Furthermore,other confounding risk factors such has obesity,prior myocardial infarction,inflammation,hypertension,birth weight,diabetes mellitus,hyperthyroidism,hormone replacement therapy in menopausal women increases the risk in the occurrence or recurrent occurrence of AF. 展开更多
关键词 Demographic trends United States Atrial fibrillation Atrial flutter Older population
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Enhanced risk assessment framework integrating distribution dynamics,genetically inferred populations,and morphological traits of Diploderma lizards 被引量:1
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作者 Qi Xiao Xiu-Dong Shi +5 位作者 Lin Shi Zhong-Yi Yao You-Hua Chen Wei-Zhao Yang Zi-Yan Liao Yin Qi 《Zoological Research》 2025年第1期15-26,共12页
Assessing the threat status of species in response to global change is critical for biodiversity monitoring and conservation efforts.However,current frameworks,even the IUCN Red List,often neglect critical factors suc... Assessing the threat status of species in response to global change is critical for biodiversity monitoring and conservation efforts.However,current frameworks,even the IUCN Red List,often neglect critical factors such as genetic diversity and the impacts of climate and land-use changes,hindering effective conservation planning.To address these limitations,we developed an enhanced extinction risk assessment framework using Diploderma lizards as a model.This framework incorporates long-term field surveys,environmental data,and land-use information to predict distributional changes for 10 recently described Diploderma species on the Qinghai-Xizang Plateau,which hold ecological significance but remain underassessed in conservation assessment.By integrating the distribution data and genetically inferred effective population sizes(Ne),we conducted scenario analyses and used a rank-sum approach to calculate Risk ranking scores(RRS)for each species.This approach revealed significant discrepancies with the IUCN Red List assessments.Notably,D.yangi and D.qilin were identified as facing the highest extinction risk.Furthermore,D.vela,D.batangense,D.flaviceps,D.dymondi,D.yulongense,and D.laeviventre,currently classified as“Least Concern”,were found to warrant reclassification as“Vulnerable”due to considerable threat from projected range contractions.Exploring the relationship between morphology and RRS revealed that traits such as snout-vent length and relative tail length could serve as potential predictors of extinction risk,offering preliminary metrics for assessing species vulnerability when comprehensive data are unavailable.This study enhances the precision of extinction risk assessment frameworks and demonstrates their capacity to refine and update risk assessments,especially for lesser-known taxa. 展开更多
关键词 LIZARD Extinction Risk Assessment IUCN Red List Conservation Status Effective population Size Morphological Traits
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Development and Validation of Machine Learning Models for Lung Cancer Risk Prediction in High-Risk Population: A Retrospective Cohort Study 被引量:1
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作者 Yu Su Haoran Zhan +5 位作者 Shangyao Li Yitong Lu Ruhuan Ma Hai Fang Tingting Xu Yu Tian 《Biomedical and Environmental Sciences》 2025年第4期501-505,共5页
Lung cancer, the leading cause of cancer deaths worldwide and in China, has a 19.7% five-year survival rate due to terminal-stage diagnosis^([1-3]).Although low-dose computed tomography(CT) screening can reduce mortal... Lung cancer, the leading cause of cancer deaths worldwide and in China, has a 19.7% five-year survival rate due to terminal-stage diagnosis^([1-3]).Although low-dose computed tomography(CT) screening can reduce mortality, high false positive rates can create economic and psychological burdens. 展开更多
关键词 lung cancer retrospective cohort study lung cancer risk prediction low dose computed tomography high risk population MORTALITY machine learning false positive rates
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Five novel ZNF469 gene mutations in sporadic keratoconus patients in the Han Chinese population
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作者 CAO Yanna DENG Zhihong +3 位作者 HE Guiyun XIAO Li ZHANG Feng SU Feng 《中南大学学报(医学版)》 北大核心 2025年第6期931-939,共9页
Objective:Keratoconus(KC)is a progressive corneal ectasia disorder,arising from a myriad of causes including genetic predispositions,environmental factors,biomechanical influences,and inflammatory reactions.This study... Objective:Keratoconus(KC)is a progressive corneal ectasia disorder,arising from a myriad of causes including genetic predispositions,environmental factors,biomechanical influences,and inflammatory reactions.This study aims to identify potential pathogenetic gene mutations in patients with sporadic KC in the Han Chinese population.Methods:Twenty-five patients with primary KC as well as 50 unrelated population matched healthy controls,were included in this study to identify potential pathogenic gene mutations among sporadic KC patients in the Han Chinese population.Sanger sequencing and whole-exome sequencing(WES)were used to analyze mutations in the zinc finger protein 469(ZNF469)gene.Bioinformatics analysis was conducted to explore the potential role of ZNF469 in KC pathogenesis.Results:Five novel heterozygous missense variants were identified in KC patients.Among them,2 compound heterozygous variants,c.8986G>C(p.E2996Q)with c.11765A>C(p.D3922A),and c.4423C>G(p.L1475V)with c.10633G>A(p.G3545R),were determined to be possible pathogenic factors for KC.Conclusion:Mutations in the ZNF469 gene may contribute to the development of KC in the Han Chinese population.These mutation sites may provide valuable information for future genetic screening of KC patients and their families. 展开更多
关键词 KERATOCONUS ZNF469 gene MUTATION Sanger sequencing Han Chinese population
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Periodic Traveling Wave Solutions of a Single Population Model with Advection and Distributed Delay
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作者 GUO Zilin YU Tao TANG Xiaosong 《应用数学》 北大核心 2025年第4期988-995,共8页
In this paper,we investigate the periodic traveling wave solutions problem for a single population model with advection and distributed delay.By the bifurcation analysis method,we can obtain periodic traveling wave so... In this paper,we investigate the periodic traveling wave solutions problem for a single population model with advection and distributed delay.By the bifurcation analysis method,we can obtain periodic traveling wave solutions for this model under the influence of advection term and distributed delay.The obtained results indicate that weak kernel and strong kernel can both deduce the existence of periodic traveling wave solutions.Finally,we apply the main results in this paper to Logistic model and Nicholson’s blowflies model. 展开更多
关键词 Single population model Advection Distributed delay Periodic traveling wave solution
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Genetic differentiations between randomly and selectively bred pig populations in Yunnan,China 被引量:10
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作者 亐开兴 吴桂生 +4 位作者 苟潇 严达伟 连林生 Mumtaz Baig 张亚平 《Zoological Research》 CAS CSCD 北大核心 2011年第3期255-261,共7页
To assess the genetic diversity between randomly and selectively bred populations,we sequenced 438 bp of the mitochondrial DNA control region from 102 pigs.These samples represented four native pig breeds,one nucleus ... To assess the genetic diversity between randomly and selectively bred populations,we sequenced 438 bp of the mitochondrial DNA control region from 102 pigs.These samples represented four native pig breeds,one nucleus and one conservation herd from Yunnan,China.Twenty haplotypes with sixteen polymorphic sites were identified.The number of haplotypes in the nucleus herd of Saba pig and the conservation herd of Banna miniature pig were restricted to three and one,respectively,while the randomly bred pig populations exhibited over six haplotypes.Notably,haplotype diversity in randomly bred populations was significantly greater than the selectively bred populations(h=0.732 vs.0.425 and 0,exact test,P≤0.0036).These findings demonstrate that selective breeding generated low genetic diversity compared to randomly bred pig breeds.A timely intervention and well programmed breeding approach would stop further genetic diversity reduction in the nucleus and conservation herds of native pig breeds.Otherwise,selective breeding would dramatically reduce genetic diversity in only several years,indicating that sharp contradictions exist between breeding,conservation and genetic diversity.Genetic relationships are discussed based on net genetic distances among pig populations. 展开更多
关键词 Yunnan pig breeds Genetic diversity Randomly bred population Selectively bred population
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Expression quantitative trait loci(eQTL):from population genetics to precision medicine
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作者 Zhi Qi Wong Lian Deng +5 位作者 Alvin Cengnata Thuhairah Abdul Rahman Aletza Mohd Ismail Renee Lay Hong Lim Shuhua Xu Boon-Peng Hoh 《Journal of Genetics and Genomics》 2025年第4期449-459,共11页
Evidence has shown that differential transcriptomic profiles among human populations from diverse ancestries,supporting the role of genetic architecture in regulating gene expression alongside environmental stimuli.Ge... Evidence has shown that differential transcriptomic profiles among human populations from diverse ancestries,supporting the role of genetic architecture in regulating gene expression alongside environmental stimuli.Genetic variants that regulate gene expression,known as expression quantitative trait loci(eQTL),are primarily shaped by human migration history and evolutionary forces,likewise,regulation of gene expression in principle could have been influenced by these events.Therefore,a comprehensive understanding of how human evolution impacts eQTL offers important insights into how phenotypic diversity is shaped.Recent studies,however,suggest that eQTL is enriched in genes that are selectively constrained.Whether eQTL is minimally affected by selective pressures remains an open question and requires comprehensive investigations.In addition,such studies are primarily dominated by the major populations of European ancestry,leaving many marginalized populations underrepresented.These observations indicate there exists a fundamental knowledge gap in the role of genomics variation on phenotypic diversity,which potentially hinders precision medicine.This article aims to revisit the abundance of eQTL across diverse populations and provide an overview of their impact from the population and evolutionary genetics perspective,subsequently discuss their influence on phenomics,as well as challenges and opportunities in the applications to precision medicine. 展开更多
关键词 EQTL TRANSCRIPTOMICS GENOMICS PHENOMICS population genetics Precisionmedicine
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Climate Change’s Impact on Honeybee Distribution and Population,Habitats,Bioproducts,and Pest Threats as Protective of SDGs
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作者 Mohamed Ezzat Elshekh Saeed Mohammed Algarni +1 位作者 Ahmed Osman Abbas Farid Saber Nassar 《Journal of Environmental & Earth Sciences》 2025年第5期108-116,共9页
Bees are essential to human life and ecosystems,significantly contributing to medicine,economics,and environmental equilibrium.Bees serve an essential function as pollinators,facilitating the cultivation of various fr... Bees are essential to human life and ecosystems,significantly contributing to medicine,economics,and environmental equilibrium.Bees serve an essential function as pollinators,facilitating the cultivation of various fruits and vegetables.Bees contribute approximately 117 billion US dollars annually to the economy through their role in crop pollination.They have a direct impact on 35%of agricultural crops and 84%of cultivated plants.Bee products,including honey,propolis,and royal jelly,have been utilized in various traditional medicine practices across numerous countries.These substances have been utilized for their anti-inflammatory,antioxidant,and antibacterial properties.In addition to their economic,ecological,and medical significance,they serve as bioindicators for assessing the health of ecological systems by monitoring distribution and population dynamics.This offers important insights into the current situation,especially regarding the substantial impacts of climate change on the environment.This article seeks to synthesize data from various studies to examine the impact of climate change on bee populations and their habitats.This study illustrates the significant effects of future climate models for 2050 and 2070 on bee distribution,resulting in the decline of specific species populations. 展开更多
关键词 Bee Distribution Bee population Climate Change Ecology Biodiversity
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Modeling deforestation due to population growth and wood industrialization
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作者 Nita H.Shah Ekta N.Jayswal Ankush H.Suthar 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第4期763-772,共10页
More than 30%of the earth's land surface is covered by the forest.Increase in population undergoes activities like construction,grazing,agriculture activities,and industrialization causing permanent clearing of la... More than 30%of the earth's land surface is covered by the forest.Increase in population undergoes activities like construction,grazing,agriculture activities,and industrialization causing permanent clearing of land to make room for something besides the forest,which is called deforestation.Considering this scenario,the mathematical model is framed for studying the dynamics with using four compartments such as deforestation of the dense forest,deforestation of the urban forest,population growth and wood industrialization.Using the dynamical phenomenon,the boundedness of the system is proposed.The proposed model has five equilibria.Behaviour of the system around all feasible equilibria is scrutinized through local stability theory of diferential equations.The 3d phase portrait gives the chaotic behavior of each compartment.Basic reproduction number value assists the bifurcation and the sensitivity analysis.Bifurcation analysis gives the ideal value,then the comparison of threshold and ideal value suggests the permissible situation of the compartment.For these findings,analytics results are verified through numerically validated data. 展开更多
关键词 DEFORESTATION population growth wood industries BIFURCATION sensitivity analysis.
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Environmental stability via sexual reproduction of cyclical parthenogenetic rotifers affects offspring's population performances:maternal effects on population dynamics
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作者 Huanhuan XU Yingying GE +1 位作者 Kangning LIU Cuijuan NIU 《Journal of Oceanology and Limnology》 2025年第6期1892-1901,共10页
Environmental fluctuations are a pervasive natural phenomenon that typically favor diverse maternal investment strategies.Organisms across various evolutionary lineages have acquired the ability to enter the dormancy ... Environmental fluctuations are a pervasive natural phenomenon that typically favor diverse maternal investment strategies.Organisms across various evolutionary lineages have acquired the ability to enter the dormancy state to tolerate conditions that are unsuitable for normal life activities.In cyclical parthenogenesis,sexual reproduction is generally linked with dormancy,thereby enhancing the long-term fitness of populations through positive feedback mechanisms.This study evaluates the impact of environmental variability on offspring population dynamics through sexual reproduction in the rotifer Brachionus calyciflorus.We found that mictic females(sexual females)exposed to low-predictability environments produced resting eggs with a sporadic hatching pattern,reduced hatching rate,and smaller sizes of resting egg,embryo,and stem females,while increasing variations in fertilization among individuals to maximize population fitness.Variations in population growth could be manifested in enhanced reproductive capacity 2–3 d post-hatching,along with differences in fecundity among individuals.This suggests that dormant eggs from unstable environments may prioritize offspring survival and adjust to increased fertilization among individuals.This adaptive strategy enables rotifer populations to rapidly adjust to environmental changes,thus avoiding extinction and thriving in diverse habitats.Our systematic study enhances the understanding of how environmental stability affects long-term population fitness in cyclical parthenogens. 展开更多
关键词 environmental stability maternal effect sexual reproduction population regulation Brachionus calyciflorus ZOOPLANKTON
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Comment on“Development of an accelerometer age-and sex-specific approach based on population-standardized values for physical activity surveillance:A proof of concept”
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作者 Alex V.Rowlands Richard P.Troiano 《Journal of Sport and Health Science》 2025年第2期79-81,共3页
Device-based measurements are recommended to improve population-based physical activity(PA)surveillance.1,2However,implementation remains challenging due to lack of consensus on analytical methods,and the most widely ... Device-based measurements are recommended to improve population-based physical activity(PA)surveillance.1,2However,implementation remains challenging due to lack of consensus on analytical methods,and the most widely used“generic”(absolute intensity)cut-point approach has limited generalisability to population-level free-living data.Further,current methods generally fail to account for differences in people's physical capacity. 展开更多
关键词 ACCELEROMETER cut point approach physical activity age specific population standardized analytical methodsand analytical methods sex specific
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High-quality reference genome decoding and population evolution analysis of prickly Sechium edule
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作者 Xiaojing Wang Shaoqin Shen +3 位作者 Yanhong Fu Rui Cao Yunfeng Wei Xiaoming Song 《Horticultural Plant Journal》 2025年第2期827-838,共12页
Sechium edule(chayote)is an important vegetable crop belonging to the Cucurbitaceae family.To decipher the chayote genome,a highquality chromosome-level chayote genome was obtained by genome sequencing and bioinformat... Sechium edule(chayote)is an important vegetable crop belonging to the Cucurbitaceae family.To decipher the chayote genome,a highquality chromosome-level chayote genome was obtained by genome sequencing and bioinformatic analysis.The total length was612.91 Mb,and 25755 genes were detected in the chayote genome.The contig N50 was more than 20.01 Mb,and the scaffold N50 was over47.11 Mb.Of the genome,60.35%were composed of repetitive sequences,and 31.18%of genome sequences belonged to long-terminal repeats.A global alignment of homologous regions in chayote and other Cucurbitaceae plant genomes was constructed using grape as a reference.Based on this genome-wide and global alignment map,researchers can easily identify homologous collinear genes of the studied genomes in most Cucurbitaceae species.Twenty-five chayote accessions were divided into two subgroups based on phylogenetic tree,population structure analysis,and principal component analysis using genome re-sequencing data.The chayote genome,re-sequencing dataset,and comprehensive genomic analysis will accelerate comparative and functional genomic analysis of chayote and other Cucurbitaceae species in the future. 展开更多
关键词 Sechium edule Whole-genome duplication Divergence time Genome evolution population structure CUCURBITACEAE
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