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Real-Time Analysis of COVID-19 Pandemic on Most Populated Countries Worldwide 被引量:2
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作者 Meenu Gupta Rachna Jain +1 位作者 Akash Gupta Kunal Jain 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第12期943-965,共23页
The spread of the Severe Acute Respiratory Syndrome Coronavirus 2(SARS-CoV-2)has already taken on pandemic extents,influencing even more than 200 nations in a couple of months.Although,regulation measures in China hav... The spread of the Severe Acute Respiratory Syndrome Coronavirus 2(SARS-CoV-2)has already taken on pandemic extents,influencing even more than 200 nations in a couple of months.Although,regulation measures in China have decreased new cases by over 98%,this decrease is not the situation everywhere,and most of the countries still have been affected by it.The objective of this research work is to make a comparative analysis of the top 5 most populated countries namely United States,India,China,Pakistan and Indonesia,from 1st January 2020 to 31st July 2020.This research work also targets to predict an increase in the number of deaths and total infected cases in these five countries.In our research,the performance of the proposed framework is determined by using three Machine Learning(ML)regression algorithms namely Linear Regression(LR),Support Vector Regression(SVR),andRandom Forest(RF)Regression.The proposed model is also validated upon the infected and death cases of further dates.The performance of these three algorithms is compared using the RootMean Square Error(RMSE)metrics.Random Forest algorithm shows best performance as compared to other proposed algorithms,with the lowest RMSE value in the prediction of total infected and total deaths cases for all the top five most populated countries. 展开更多
关键词 COVID-19 SARS COV-2 country-wise analysis most populated countries PANDEMIC mortality rate
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ZTE Chairman Bullish on Telecom Business Opportunities in Developing and Densely Populated Nations
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《ZTE Communications》 2007年第4期2-2,共1页
ZTE Corporation (ZTE), a leading global provider of telecommunications equipment and network solutions, recently
关键词 ZTE Chairman Bullish on Telecom Business Opportunities in Developing and Densely populated Nations
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Is China Over-Populated?
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作者 O.W.TU 《地理学报》 1935年第1期183-183,共1页
The object of this paper is to show that the general poverty of the Chinese people is not caused by over-population,but by the primitive methods of produc.tion,the existing system of exploitation,the political chaos a... The object of this paper is to show that the general poverty of the Chinese people is not caused by over-population,but by the primitive methods of produc.tion,the existing system of exploitation,the political chaos and the political and economical exploitation of the imperialistic powers. 展开更多
关键词 system exploitation methods production POPULATION political chaos system exploitationthe POVERTY political economical exploitation
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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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Mapping world’s coastal population facing water-related risks
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作者 Olli Varis Maija Taka Matti Kummu 《Geography and Sustainability》 2026年第1期206-217,共12页
Endowed with opportunities from both land and ocean,coastal areas attract expanding human populations and economic activities.At the same time,they face growing societal and environmental pressures from both the above... Endowed with opportunities from both land and ocean,coastal areas attract expanding human populations and economic activities.At the same time,they face growing societal and environmental pressures from both the above river catchments and the bordering sea due to climate change,ecosystem degradation,and expansion of built-up areas.Despite the accumulation of human population,economic activities,and environmental impacts,we lack social-ecological systems analysis on water-related risks to world’s coastal human population.To address this research gap,we analyze the spatial extent of six globally important water stressors to people within the world’s coastal zone(100 km from the coastal line)and classify this zone globally into 12 groups by distance from the coastline and elevation from the mean sea level.Adopting the approaches of the UN Sendai Framework and IPCC,we produce risk maps from the stressor maps by multiplying them with population exposure and vulnerability.For most risks,geographical hotspots are the Chinese coast,Bay of Bengal,Gujarat,and the Island of Java.The analysis reveals fundamental differences between water stressors and related risks,often mixed in scholarly literature.Both manifest specific geographic patterns and latitudinal profiles.Our study highlights the importance of high-resolution spatial analysis of vulnerability,exposure,and risks posed by water related stressors in the world’s coastal zone,in a manner prompted by key policy bodies to promote policy design and shared responsibility for managing stress-prone areas. 展开更多
关键词 Coastal zone POPULATION RiskSocial-ecological systems Spatial analysis Water
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Enlarged Sink Capacity and Optimized Population Physiological Characteristics are Key to High Yield in Conventional Japonica Rice
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作者 ZHANG Haipeng MI Kailiang +3 位作者 CHEN Ting ZHANG Muyan XU Fangfu ZHANG Hongcheng 《Rice science》 2026年第1期113-128,I0081-I0095,共31页
Clarifying the photosynthetic and population characteristics of conventional japonica rice at different yield levels is crucial for boosting yield and ensuring food security.Therefore,a two-year field trial with two c... Clarifying the photosynthetic and population characteristics of conventional japonica rice at different yield levels is crucial for boosting yield and ensuring food security.Therefore,a two-year field trial with two conventional japonica varieties was conducted at four planting densities:16 cm×30 cm(D1),14 cm×30 cm(D2),12 cm×30 cm(D3),and 10 cm×30 cm(D4).This study aimed to investigate how photosynthetic and population characteristics influence grain yield under varying planting densities.The results indicated that higher yields were primarily driven by increased grain weight and seed-setting rate(with a 9.68%‒11.40%higher single panicle weight),supported by optimized dry matter translocation and source-sink relationships.Elevated planting density(D2‒D4)enhanced panicle number and total spikelet number(by 3.91%‒15.00%)but reduced the number of spikelets per panicle,1000-grain weight,and photosynthetic efficiency due to mutual shading.Despite these trade-offs,yield increased by 4.10%‒12.42%under higher densities.The use of planting density D4 in japonica rice cultivation contributed to maximize yield.These findings provide important theoretical insights and practical significance for increasing the yield of conventional japonica rice and ensuring food security. 展开更多
关键词 conventional japonica YIELD population characteristics photosynthetic efficiency planting density
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Metformin remodels the myelin landscape
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作者 Bandy Chen 《Neural Regeneration Research》 2026年第3期1120-1121,共2页
The rapidly aging population directly contributes to the increasing cases of neurological disorders.Due to the chronic progressive nature of neurodegeneration,numerous neurological conditions are considered“multifact... The rapidly aging population directly contributes to the increasing cases of neurological disorders.Due to the chronic progressive nature of neurodegeneration,numerous neurological conditions are considered“multifactorial”with systemic metabolic alterations.Even so,treatments for neurological disorders have remained unchanged for the past decades.Recently,metabolic drugs such as metformin and glucagon-like peptide 1 agonists have demonstrated promising health outcomes for neurodegeneration. 展开更多
关键词 metabolic alterations TREATMENTS neurological disordersdue neurological disorders METFORMIN myelin landscape NEURODEGENERATION aging population
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Muscle mass correlates with rocuronium distribution volume and guides dose optimization in obese colorectal cancer patients
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作者 Zhan-Wen Li Zhe Liu Sheng-Qun Liu 《World Journal of Gastrointestinal Oncology》 2026年第1期176-189,共14页
BACKGROUND Perioperative anesthesia management of obese patients presents significant challenges as traditional total body weight-based dosing fails to achieve optimal anesthetic effects due to altered pharmacokinetic... BACKGROUND Perioperative anesthesia management of obese patients presents significant challenges as traditional total body weight-based dosing fails to achieve optimal anesthetic effects due to altered pharmacokinetic characteristics including abnormal drug distribution and clearance.Rocuronium exhibits markedly different distribution patterns in obese patients,with conventional weight correction methods inadequately addressing individual muscle mass variations that critically influence drug distribution.AIM To investigate the quantitative relationship between skeletal muscle index(SMI)and rocuronium distribution volume in obese colorectal cancer patients,establish a population pharmacokinetic model,and develop individualized dosing strategies based on muscle mass.METHODS A retrospective cohort study was conducted,including 100 obese patients(body mass index≥30 kg/m^(2))who underwent elective radical colorectal cancer surgery at our hospital from June 2023 to January 2025.Skeletal muscle mass was measured using InBody 260 body composition analyzer and SMI was calculated to assess muscle mass,with male SMI<7.0 kg/m^(2) and female SMI<5.7 kg/m^(2)as diagnostic criteria for sarcopenia.Plasma rocuronium concentrations were detected by liquid chromatography-tandem mass spectrometry/mass spectrometry,and nonlinear mixed-effect modeling was used to establish population pharmacokinetic modeling.Stepwise regression was used to screen covariates,and dosing regimens were optimized through Monte Carlo simulation.The primary endpoint was targeted plasma concentration achievement rate,and the secondary endpoint was postoperative residual muscle relaxation incidence.RESULTS Among 100 patients,35(35.0%)had sarcopenia and 65(65.0%)did not.Patients in the sarcopenia group were older(64.1±9.8 years vs 54.2±10.9 years,P<0.001)and had significantly lower SMI(6.2±0.8 kg/m^(2)vs 8.4±1.2 kg/m^(2),P<0.001).SMI showed strong positive correlation with rocuronium steady-state distribution volume(r=0.718,P<0.001)and moderate negative correlation with clearance(r=-0.502,P<0.001).A two-compartment population pharmacokinetic model was successfully established,with SMI being the most important covariate affecting central compartment distribution volume(△OFV=-41.2,P<0.001).Model validation showed bootstrap successful convergence rate of 92.3%,and 92.1%of observed values fell within prediction intervals in predicted concentration versus predicted concentration.The SMI-based individualized dosing regimen improved target exposure achievement rate from 82.0%in traditional regimen to 93.5%(P=0.009),and reduced postoperative residual muscle relaxation incidence from 13.0%to 3.5%(P=0.018).The sarcopenia group showed the most significant improvement in achievement rate,from 71.4%to 93.8%(P=0.017).CONCLUSION SMI shows strong correlation with rocuronium distribution volume in obese colorectal cancer patients and is a key factor affecting drug distribution.SMI-based individualized dosing strategies can significantly improve target exposure achievement rate and reduce postoperative residual muscle relaxation incidence,providing scientific evidence for precision anesthesia management in obese patients. 展开更多
关键词 Obesity ROCURONIUM Skeletal muscle index Population pharmacokinetics Individualized dosing Colorectal cancer SARCOPENIA
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China’s Urban Labor Market in Transition:New Findings from the Fifth Survey
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作者 Jia Peng Cheng Jie Qu Yue 《China Economist》 2026年第1期92-114,共23页
To gain an in-depth understanding of China’s urban labor market,the Institute of Population and Labor Economics at the Chinese Academy of Social Sciences(IPLE-CASS)conducted the fifth wave of the China Urban Labor Su... To gain an in-depth understanding of China’s urban labor market,the Institute of Population and Labor Economics at the Chinese Academy of Social Sciences(IPLE-CASS)conducted the fifth wave of the China Urban Labor Survey in 2023,which covers eight major representative cities.The survey collected 9,122 household questionnaires and 26,145 individual questionnaires from 381 neighborhood committees.Based on this data,the report systematically analyzes employment,wages,educational attainment,and social security among China’s urban workforce.Key findings include an inverted U-shaped age pattern of labor force participation,with a widening gender gap after childbearing age.Additionally,job search methods combine market-based channels with traditional social networks.Notably,the gender wage gap persists and widens over the life cycle,while employed women now have higher average years of schooling than men.Rural-to-urban migrants show higher labor force participation rates but remain disadvantaged in wages,education,and social security coverage.Thus,this survey provides a comprehensive picture of the structural characteristics and challenges of China’s urban labor market,providing a solid data foundation for academic research and public policy design. 展开更多
关键词 Household survey labor market EMPLOYMENT migrant population
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Limited growth and recruitment of Oikopleura dioica(Tunicata:Appendicularia)in the Jiaozhou Bay,China
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作者 Shuai LI Mengtan LIU +5 位作者 Aiyong WAN Zhiqiang XU Shiwei WANG Yi LIANG Zengxia ZHAO Guangtao ZHANG 《Journal of Oceanology and Limnology》 2026年第1期234-250,共17页
Pelagic appendicularians,known for their rapid bloom capability,are important secondary producers and play essential roles in marine ecosystems.To assess the environmental adaptation of the most common appendicularian... Pelagic appendicularians,known for their rapid bloom capability,are important secondary producers and play essential roles in marine ecosystems.To assess the environmental adaptation of the most common appendicularian species Oikopleura dioica in Jiaozhou Bay,Shandong,China,its annual variations in abundance and body size were investigated monthly at 12 stations in 2011,and the relationship between somatic growth and gonadal development was compared with previously published laboratory data.Oikopleura dioica exhibited distinct seasonal abundance patterns,peaking in summer and autumn,particularly in the inner bay,reflecting its adaptation to the eutrophic conditions and high food availability.Compared to laboratory results,O.dioica in Jiaozhou Bay exhibited shorter body lengths,smaller gonad volumes,and earlier maturation at reduced body sizes,despite high natural chlorophyll-a concentration,suggesting that factors beyond food availability,such as resource competition and environmental stressors,may limit its growth in natural settings.Correlation analysis indicated that the somatic growth of natural O.dioica was primarily influenced by temperature,while gonadal development was related to chlorophyll-a concentration,and its population abundance was linked to food availability and the abundance of other zooplankton,such as copepods and jellyfish.It was suggested that the growth and recruitment of O.dioica were constrained by resource limitations in natural environments,further exacerbated by interactions with other zooplankton,including predation and competition.This study provides valuable data on the mechanisms underlying bio-environmental interactions and their spatiotemporal variations,offering critical insights into the ecological roles of appendicularians in marine ecosystems. 展开更多
关键词 Oikopleura dioica body size size-at-maturation food limitation Jiaozhou Bay population recruitment
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Wind-induced circulation driving the spatial distribution of dominant algae population in a plateau lake,Erhai,China
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作者 Jing Cao Yue Wu +4 位作者 Zeying Hou Kunlin Yang Zhaosheng Chu Zhiwei Gao Hao Yang 《Journal of Environmental Sciences》 2026年第1期741-755,共15页
Wind-induced circulation is the main form of lake flow for shallow lakes and plays an important role in algae population distribution.This study constructed a three-dimensional hydrodynamic model(EFDC)of the plateau l... Wind-induced circulation is the main form of lake flow for shallow lakes and plays an important role in algae population distribution.This study constructed a three-dimensional hydrodynamic model(EFDC)of the plateau lake Erhai,China using accuracy wind field observation,runoff data and monthly algae data during 2022–2023.The model successfully reproduced the circulation characteristics of Erhai under prevailing wind directions.The results showed that the lake flow velocity in Lake Erhai is higher in winter than in summer,with lower velocities near shore particularly in the northern and central parts of the lake.There is a negative correlation between algal biomass and flow velocity(FV)in different zones,with lower FV favoring the accumulation of algal biomass,particularly for Microcystis,Dolichospermum,and Peridinium.Additionally,due to buoyancy,cyanobacteria are highly affected by wind direction and tend to accumulate in downwind regions of the prevailing wind direction.This study demonstrates that wind-induced circulation is a crucial factor affecting the spatial distribution of dominant algae populations in shallow plateau lakes with weak hydrodynamic force.Further,the risk of bloom occurrence in Lake Erhai will be higher due to the background of global climate change and the lake’s wind speed decline.In conclusion,we suggest implementing targeted zoning measures to control algal blooms and establishing stricter regulations for nitrogen and phosphorus control to counterbalance the promotion of algal bloom accumulation in low-velocity zones caused by reduced wind speed. 展开更多
关键词 Wind-induced circulation Dominant algae populations Three-dimensional hydrodynamic model MICROCYSTIS Peridinium
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Quiet Revival
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《ChinAfrica》 2026年第1期4-5,共2页
Elk are seen at the Tian’ezhou National Nature Reserve for Elk in Shishou,Hubei Province,on 27 November 2025.The reserve’s elk population has risen from just 64 in the 1990s to more than 4,500 today.
关键词 hubei province ELK tianezhou national nature reserve shishou quiet revival population rise s
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Collaborative scheduling problem pertaining to launch and recovery operations for carrier aircraft
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作者 GUO Fang HAN Wei +3 位作者 LIU Yujie SU Xichao LIU Jie LI Changjiu 《Journal of Systems Engineering and Electronics》 2026年第1期287-306,共20页
The proliferation of carrier aircraft and the integration of unmanned aerial vehicles(UAVs)on aircraft carriers present new challenges to the automation of launch and recovery operations.This paper investigates a coll... The proliferation of carrier aircraft and the integration of unmanned aerial vehicles(UAVs)on aircraft carriers present new challenges to the automation of launch and recovery operations.This paper investigates a collaborative scheduling problem inherent to the operational processes of carrier aircraft,where launch and recovery tasks are conducted concurrently on the flight deck.The objective is to minimize the cumulative weighted waiting time in the air for recovering aircraft and the cumulative weighted delay time for launching aircraft.To tackle this challenge,a multiple population self-adaptive differential evolution(MPSADE)algorithm is proposed.This method features a self-adaptive parameter updating mechanism that is contingent upon population diversity,an asynchronous updating scheme,an individual migration operator,and a global crossover mechanism.Additionally,comprehensive experiments are conducted to validate the effectiveness of the proposed model and algorithm.Ultimately,a comparative analysis with existing operation modes confirms the enhanced efficiency of the collaborative operation mode. 展开更多
关键词 carrier aircraft collaborative scheduling problem LAUNCH RECOVERY multiple population differential evolution
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ATLAS study:Design,athletic performance,and sex-specific regression models for muscle strength in the Greek population
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作者 Natia A.Pogosova Despoina Brekou +7 位作者 Ioanna E.Gavra Efthymia A.Katsareli Eleni More Panagiotis G.Symianakis Maria Kafyra Ioanna Panagiota Kalafati Giannis Arnaoutis George V.Dedoussis 《Sports Medicine and Health Science》 2026年第1期79-95,共17页
Purpose:ATLAS is a cross-sectional study aiming to investigate environmental and genetic determinants of athletic performance in healthy Greek competitive athletes(CA).This article presents the study design,investigat... Purpose:ATLAS is a cross-sectional study aiming to investigate environmental and genetic determinants of athletic performance in healthy Greek competitive athletes(CA).This article presents the study design,investigates the muscle strength performance(MSP)of 289 adult and teenage CA,exercisers,and physically inactive individuals(PI),and proposes predictive models of MSP for adults.Methods:Muscle maximal,speed,and explosive strength(MMS/MSS/MES)at unilateral maximal concentric flexion and extension contraction(FC/EC)were evaluated using Biodex System 3 PRO^(TM)at 60°/s,180°/s,and 300°/s,while additional performance markers were assessed through field ergometric testing.Participants were interviewed about their lifestyle,dietary habits,physical activity,injury,and medical history.Body composition was assessed via bioelectrical impedance.gDNA was extracted from biochemical samples and then genotyped.Statistical analysis was conducted using IBM SPSS Statistics v21.0 and R.Results:Age,fitness,and sex impacted correlations of MSP with body composition and anthropometric measurements(p<0.05).Among CA,females outperformed males in accuracy(p<0.001)while,males outperformed females in anaerobic power,MSP,speed,and endurance(p<0.001).Adult CA outperformed exercisers and PI in MMS,MSS,and MES(p<0.05).Multiple linear regression models,with predictors age,FFM,body extremity,training load explained the majority of variation in MMS(R^(2)_(adj):71.4%–88.9%),MSS(R^(2)_(adj):64.8%–78.4%),and MES(R^(2)_(adj):52.7%–68.4%)at EC,FC,and their mean(p<0.001).Conclusions:Muscle-strengthening strategies should be customized according to individual fitness levels,body composition,and anthropometric measurements.The innovative sex-specific regression models assessing MMS,MSS,and MES at EC and FC provide a framework for personalizing rehabilitation and skill-specific training strategies. 展开更多
关键词 Athletic performance Isokinetic dynamometer Muscle strength performance Greek population Predictive models Body composition
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Improved Cuckoo Search Algorithm for Engineering Optimization Problems
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作者 Shao-Qiang Ye Azlan Mohd Zain Yusliza Yusoff 《Computers, Materials & Continua》 2026年第4期1607-1631,共25页
Engineering optimization problems are often characterized by high dimensionality,constraints,and complex,multimodal landscapes.Traditional deterministic methods frequently struggle under such conditions,prompting incr... Engineering optimization problems are often characterized by high dimensionality,constraints,and complex,multimodal landscapes.Traditional deterministic methods frequently struggle under such conditions,prompting increased interest in swarm intelligence algorithms.Among these,the Cuckoo Search(CS)algorithm stands out for its promising global search capabilities.However,it often suffers from premature convergence when tackling complex problems.To address this limitation,this paper proposes a Grouped Dynamic Adaptive CS(GDACS)algorithm.Theenhancements incorporated intoGDACS can be summarized into two key aspects.Firstly,a chaotic map is employed to generate initial solutions,leveraging the inherent randomness of chaotic sequences to ensure a more uniform distribution across the search space and enhance population diversity from the outset.Secondly,Cauchy and Levy strategies replace the standard CS population update.This strategy involves evaluating the fitness of candidate solutions to dynamically group the population based on performance.Different step-size adaptation strategies are then applied to distinct groups,enabling an adaptive search mechanism that balances exploration and exploitation.Experiments were conducted on six benchmark functions and four constrained engineering design problems,and the results indicate that the proposed GDACS achieves good search efficiency and produces more accurate optimization results compared with other state-of-the-art algorithms. 展开更多
关键词 Cuckoo search algorithm chaotic transformation population division adaptive update strategy Cauchy distribution
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Increasing meridional disparity of population exposure to heat stress
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作者 Xiaofan Xu Yuxiao Kong +5 位作者 Jintao Zhang Jianping Duan Minghong Tan Xue Yang Hongzhou Zhu Deliang Chen 《Geography and Sustainability》 2026年第1期95-105,共11页
Global warming and socioeconomic development are expected to exacerbate human exposure to heat stress,but the extent and inequality of such changes remain unclear.Here,we quantified the future population exposure to h... Global warming and socioeconomic development are expected to exacerbate human exposure to heat stress,but the extent and inequality of such changes remain unclear.Here,we quantified the future population exposure to heat stress(PEHS)under different Shared Socioeconomic Pathways(SSPs)and Representative Concentration Pathways(RCPs)scenarios using a novel decomposition framework that separates the contributions of climate change,population change,and their interaction.Results show that global PEHS will increase substantially during the 21st century,with low-latitude regions experiencing the largest absolute increases,and high-latitude regions facing the largest relative increases.Globally,projected increases in PEHS under SSP3-7.0 are roughly three times those under SSP1-2.6,with low latitudes contributing about 70%-75%of the global total.SSP1-2.6 most effectively limits future heat exposure,with the highest risks in low-latitude developing regions,underscoring the need for low-emission pathways and targeted population and urbanization management.The findings highlight the urgent need for both climate mitigation and population adaptation strategies to address the growing and uneven heat exposure risks worldwide. 展开更多
关键词 Population exposure Extreme heatwave Meridional disparity
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Comparative evaluation of sterilizing potential of intratesticular chemosterilants in male albino rats
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作者 Abdul Salam Ansari Timanshi Chansoriya +1 位作者 Barkha Khilwani Nirmal Kumar Lohiya 《Asian pacific Journal of Reproduction》 2026年第1期34-44,共11页
Objective:To investigate the sterilizing potential of zinc gluconate,calcium chloride(CaCl_(2))and cadmium chloride(CdCl_(2))following a single intratesticular administration in adult male rats.Methods:60 adult male W... Objective:To investigate the sterilizing potential of zinc gluconate,calcium chloride(CaCl_(2))and cadmium chloride(CdCl_(2))following a single intratesticular administration in adult male rats.Methods:60 adult male Wistar albino rats(Rattus norvegicus)weighing 160-200 g and aged 5-6 months randomly received a single intratesticular injection of normal saline(Group A),zinc gluconate 13.3 mg/mL plus L-Arginine(Group B),20%CaCl_(2)(Group C),and CdCl_(2)0.5 mg/kg body weight plus ethylenediaminetetraacetic acid(EDTA)(Group D),respectively,along the entire route from the caudoventral aspect of each testis.They were euthanized up to 180 days to evaluate reproductive tract toxicology.Results:The reproductive organ weights were markedly reduced,with testes severely atrophied in group B,pea-sized and stony hard in group C,and moderately reduced in group D.Azoospermia was evident in groups B and C,while sperm concentration was reduced to<1 million/mL with zero sperm motility in group D.Rats of groups B and C failed to show mounting and copulatory behaviour.A completely disorganized mesh of cellular elements was observed in the seminiferous tubules of group B,while pyknotic germ cell and arrest of spermatogenesis,exfoliated germ cells,occasional syncytial bodies and smaller Leydig cells were evident in groups C and D.Significantly reduced testosterone levels,increased luteinizing hormone(LH)and follicle-stimulating hormone(FSH)levels,returned to normal after 90 days in group D.Conclusions:Zinc gluconate and CaCl_(2)injections severely affected the reproductive organs and libido and rats treated with CdCl_(2)exhibited diminished spermatogenesis with normal libido.Thus,the need-based selection of intratesticular agents should consider their distinct effects on spermatogenesis,libido,and hormonal balance for achieving targeted sterilization outcomes. 展开更多
关键词 Zinc gluconate Calcium chloride Cadmium chloride Intratesticular chemosterilization AZOOSPERMIA Male rats Reproductive toxicity Canine population control
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Epidemiological Characteristics of Varicella and Population Immunity against Varicella-zoster Virus in Fujian Province,China,from 2018 to 2024
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作者 Shijia Wu Zhifei Chen +5 位作者 Suhan Zhang Xiuhui Yang Hairong Zhang Weiyi Pan Yong Zhou Dong Li 《Biomedical and Environmental Sciences》 2026年第2期251-255,共5页
Varicella,a highly contagious respiratory infection caused by the varicella-zoster virus(VZV),predominantly affects children and is characterized by symptoms such as low-grade fever and vesicular rash[1,2].In China,va... Varicella,a highly contagious respiratory infection caused by the varicella-zoster virus(VZV),predominantly affects children and is characterized by symptoms such as low-grade fever and vesicular rash[1,2].In China,varicella remains prevalent,with a steady increase in incidence,peaking at 70.14 cases per 100,000 individuals in 2019[3].Although the number of reported outbreaks and cases from 2020 to 2022 was lower than those from 2006 to 2012 and 2013 to 2019,varicella continues to pose a significant public health challenge[3]. 展开更多
关键词 epidemiological characteristics varicella zoster virus public health challenge Fujian province population immunity China VARICELLA respiratory infection
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MCPSFOA:Multi-Strategy Enhanced Crested Porcupine-Starfish Optimization Algorithm for Global Optimization and Engineering Design
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作者 Hao Chen Tong Xu +2 位作者 Yutian Huang Dabo Xin Changting Zhong 《Computer Modeling in Engineering & Sciences》 2026年第1期494-545,共52页
Optimization problems are prevalent in various fields of science and engineering,with several real-world applications characterized by high dimensionality and complex search landscapes.Starfish optimization algorithm(... Optimization problems are prevalent in various fields of science and engineering,with several real-world applications characterized by high dimensionality and complex search landscapes.Starfish optimization algorithm(SFOA)is a recently optimizer inspired by swarm intelligence,which is effective for numerical optimization,but it may encounter premature and local convergence for complex optimization problems.To address these challenges,this paper proposes the multi-strategy enhanced crested porcupine-starfish optimization algorithm(MCPSFOA).The core innovation of MCPSFOA lies in employing a hybrid strategy to improve SFOA,which integrates the exploratory mechanisms of SFOA with the diverse search capacity of the Crested Porcupine Optimizer(CPO).This synergy enhances MCPSFOA’s ability to navigate complex and multimodal search spaces.To further prevent premature convergence,MCPSFOA incorporates Lévy flight,leveraging its characteristic long and short jump patterns to enable large-scale exploration and escape from local optima.Subsequently,Gaussian mutation is applied for precise solution tuning,introducing controlled perturbations that enhance accuracy and mitigate the risk of insufficient exploitation.Notably,the population diversity enhancement mechanism periodically identifies and resets stagnant individuals,thereby consistently revitalizing population variety throughout the optimization process.MCPSFOA is rigorously evaluated on 24 classical benchmark functions(including high-dimensional cases),the CEC2017 suite,and the CEC2022 suite.MCPSFOA achieves superior overall performance with Friedman mean ranks of 2.208,2.310 and 2.417 on these benchmark functions,outperforming 11 state-of-the-art algorithms.Furthermore,the practical applicability of MCPSFOA is confirmed through its successful application to five engineering optimization cases,where it also yields excellent results.In conclusion,MCPSFOA is not only a highly effective and reliable optimizer for benchmark functions,but also a practical tool for solving real-world optimization problems. 展开更多
关键词 Global optimization starfish optimization algorithm crested porcupine optimizer METAHEURISTIC Gaussian mutation population diversity enhancement
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Using novel microsatellite markers to characterize genetics of asexual sea cucumber Stichopus chloronotus populations in tropical nearshore islands of the South China Sea
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作者 Xiang HU Xinxin HUANG +3 位作者 Mengjiao LIU Linwen HE Fei GAO Qiang XU 《Journal of Oceanology and Limnology》 2026年第1期219-233,共15页
Stichopus chloronotus is a tropical sea cucumber with facultative asexual reproduction in the Indo-Western Pacific,yet its wild populations are decreasing due to extensive harvesting.Understanding the species’genetic... Stichopus chloronotus is a tropical sea cucumber with facultative asexual reproduction in the Indo-Western Pacific,yet its wild populations are decreasing due to extensive harvesting.Understanding the species’genetic characteristics is essential for effective management and conservation.To develop novel microsatellite markers and assess the genetic diversity,clonality,and genetic structure of eight populations of S.chloronotus in the South China Sea,193 individuals from eight populations across Wuzhizhou and Fenjiezhou(Boundary)islands were analyzed using nine newly developed microsatellite markers and five previously established markers.RNA-Seq was employed to obtained 62662 unigenes and identified 16926 microsatellite loci.Fourteen polymorphic microsatellite loci were developed,of which 11 were highly polymorphic(polymorphic information content>0.5).The number of alleles(N_(a))ranged from 3 to 6 per locus,and the average Shannon diversity index(I)was 1.107.All the populations exhibited asexual reproduction,with regional variations in reproductive modes.Asexual reproduction was predominant in the northwestern Wuzhizhou Island population(SY 7)and the Fenjiezhou Island population(LS 8),where four and five predominant clones represented more than 89%of the individuals,which led to reduced genetic diversity.Overall,genetic diversity was moderately low,with significant genetic differentiation among populations(F_(ST)=0.33;P<0.001),suggesting limited gene flow(the number of migrants(N_(m))<1).These findings highlight the role of reproductive strategies in shaping fine-scale genetic differentiation in S.chloronotus.The limited recruitment success of sexually produced larvae and habitat heterogeneity likely constrain clone dispersal,contributing to distinct genetic restructuring.This study provided key insights into the interplay between reproductive strategies and genetic patterns in sea cucumbers,offering a scientific basis for targeted conservation efforts. 展开更多
关键词 Stichopus chloronotus microsatellite marker(SSR) population genetic diversity asexual reproduction
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