AIM:To ascertain the pattern of ocular morbidity in a population of primary school children in rural Kenya as it is a prerequisite for planning effective preventive and therapeutic strategies.METHODS:A cross-sectional...AIM:To ascertain the pattern of ocular morbidity in a population of primary school children in rural Kenya as it is a prerequisite for planning effective preventive and therapeutic strategies.METHODS:A cross-sectional survey of ocular symptoms and clinical eye examinations were performed in a sample of 35 rural primary schools in the semi-arid region of Kajiado West sub-county in S.W.Kenya,amongst a seminomadic tribe(Maasai).Students in Grades 1-8 were included.Visual acuity was measured using the Snellen“tumbling E”chart at 6 m.Children with symptoms of refractive error underwent non-cycloplegic refraction.RESULTS:A total of 2036 children(1084 males)between the ages of 4-20y were examined.Conjunctival actinic changes were present in 22%(442/2036).Nine cases were seen with a potential squamous carcinoma.No overt classical ocular signs of vitamin A deficiency were noted,although 181(8.9%)children complained of nyctalopia.Three hundred thirty-six(16.5%)children had a visual acuity worse than 6/12 in either eye,were unable to read N10 near text at 40 cm or had symptoms suggestive of refractive error.Refractive data led to an estimate of hyperopia of+1.00 D or more in 3.9%and of myopia of-0.50 D or more in either eye in 3.0%of the study population.CONCLUSION:Solar exposure-and dust-related conjunctival pathology is common.As this may develop into potentially sight-or even life-threatening conditions,it warrants further study,and preventive strategies may be needed.Complaints of nyctalopia were common and could suggest vitamin A deficiency.The prevalence of refractive errors is low in this rural African population.展开更多
Aquatic viruses are naturally present in the aquatic environment and the number of viruses is staggering.Various multicellular organisms in aquatic ecosystems may be infected,cross-species transmitted,manipulated,and ...Aquatic viruses are naturally present in the aquatic environment and the number of viruses is staggering.Various multicellular organisms in aquatic ecosystems may be infected,cross-species transmitted,manipulated,and killed by aquatic viruses,which can lead to cascading ecological effects.The viruses in unicellular aquatic organisms can alter interactions between host individuals,and are essential in effecting or maintaining the dynamics of aquatic microbial communities,horizontal gene transfer,biodiversity,and modulating ecological processes globally.Meanwhile,hosts also impact viral abundance and diversity.Microbial diversity drives multifunctionality in ecosystems,while viruses shape complex microbial communities and are crucial for ecosystem functioning.This review focuses on molecular,genetic,evolutionary,and ecosystemic advances related to emerging and reemerging aquatic viruses,presents the contexts,novel tools,and investigative approaches pertaining to the study of aquatic virology,and discusses the mechanisms by which viruses affect aquatic ecosystems.The paper provides an efficient and broadly-based blueprint for improving understanding of aquatic viruses.展开更多
Investigative identification is a routine criminal investigative procedure,the results of which can be used as evidence in litigation.However,some suspects often deny their involvement in the case,and some witnesses m...Investigative identification is a routine criminal investigative procedure,the results of which can be used as evidence in litigation.However,some suspects often deny their involvement in the case,and some witnesses may withhold information or misrepresent it,all of which may lead to a miscarriage of justice.This study created a stressful environment and conducted a simulated crime experiment to explore whether eye movement data can be an effective feature for distinguishing perpetrators,innocents,and insiders.The eye movement features—such as the total fixation duration,number of fixations,and first fixation duration—within an area of interest were collected from 83 participants sorted into informed,involved,and innocent groups.The results revealed the following:(1)compared with the object and scene stimuli,subjects with different identities were more likely to exhibit significant differences in eye movement data for the involved and irrelevant portraits.The total fixation duration and the number of fixations can provide a reference for judging whether someone is involved in a case,and the first fixation duration effect was not obvious.(2)Using machine learning algorithms to predict subjects’identities through eye movement features,it was demonstrated that the involved portrait-object-scene model had the best predictive effect.(3)Multiple algorithmic models were used to distinguish subjects’identities,and the highest accuracy of 92.7%was achieved for the informed×innocent group,88%for the innocent×suspect group(including the informed and involved groups),and 84.5%for the involved group.The eye movement analysis method can provide a reference for criminal investigators to distinguish between the perpetrator,insider,and innocent,and offer a novel approach to determining the direction of further investigation and uncovering and verifying case clues.展开更多
In this research,a comparative analysis was conducted on the performance and efficiency of the dual-anchor soft robot(DASR)and the extension-contraction soft robot(ECSR).These robots were constructed by imitating the ...In this research,a comparative analysis was conducted on the performance and efficiency of the dual-anchor soft robot(DASR)and the extension-contraction soft robot(ECSR).These robots were constructed by imitating the locomotion of razor clams.The penetration force for extension actuators and the anchorage force for expansion actuators in dry sand with distinct relative densities were tested by differentiating input air pressure and length-to-diameter ratios(λ).On the basis of the findings,a DASR and an ECSR were developed.DASR comprised two expansion actuators as the head and the tail segments at two ends,and one extension actuator as the middle segment.ECSR was composed of an extension actuator.A method based on the force equilibrium was introduced to ascertain and adjust the geometric parameters(length of each segment)of DASR.The burrowing-out performance and efficiency of DASR and ECSR in sands with distinct relative densities were explored.The results revealed that DASR exhibited high efficiency in dense sand in terms of lower time of burrowing-out,slip-to-advancement ratio,and cost of transport.ECSR might perform better in looser sand in terms of higher average burrowing-out velocity,higher advancement in each cycle,and lower energy consumption.However,it had larger slips than DASR.DASR could realize steady advancement and net displacement in each cycle and effectively decrease slips.These findings demonstrate the benefits and usability of the dual-anchor motion and offer new insights into the application of the dual-anchor mechanism in the burrowing of robots.展开更多
Recent advances in geoscience have underscored the critical role of abiogenic processes in petroleum formation,especially the formation and polymerization of methane.However,whether a direct carbon-H_(2) reaction can ...Recent advances in geoscience have underscored the critical role of abiogenic processes in petroleum formation,especially the formation and polymerization of methane.However,whether a direct carbon-H_(2) reaction can produce C_(2+)hydrocarbons(e.g.,ethane and propane)beyond methane remains an open question.Here,we demonstrate the direct synthesis of ethane and propane via reactions between amorphous carbon and H_(2) under upper mantle conditions(2-10 GPa and 800-1200℃).A systematic investigation reveals that increasing structural disorder in carbon precursors,from graphite to glassy carbon-Ⅱ and carbon black,enhances the production of C_(2)-C_(3) hydrocarbons.Through integrated X-ray diffraction and reverse Monte Carlo simulations,we establish that the continuous random atomic network structures in amorphous carbon enable one-step synthesis of heavy hydrocarbons with H_(2).These models establish a direct link between atomic-scale carbon structures and the one-step synthesis of C_(2+) hydrocarbons under H_(2)-rich,high-pressure,and high-temperature conditions—potentially revealing an efficient mechanism for the abiotic production of C_(2+) hydrocarbons in the upper mantle.展开更多
Description Journal of Building Energy Efficiency(monthly),initiated in October 2006,supplies a platform for architects,mechanical engineers,civil engineers,energy researchers,energy policy makers and building industr...Description Journal of Building Energy Efficiency(monthly),initiated in October 2006,supplies a platform for architects,mechanical engineers,civil engineers,energy researchers,energy policy makers and building industry to communicate on investigations,innovation,research and development of energy efficiency in buildings.The Journal has been classified into the“Catalog of High-quality Sci-Tech Journals of Building Science(2020,T3)”by the Architectural Society of China(ASC),certificated as the“Source Journal for Chinese Scientific and Technical Papers and Citations”by Institute of Scientific and Technical Information of China(ISTIC)since 2013 and the“China Core Academic Journal of RCCSE”by Library of Wuhan University and other cooperating institutes since 2014.展开更多
Description Journal of Building Energy Efficiency(monthly),initiated in October 2006,supplies a platform for architects,mechanicalengineers,civil engineers,energy researchers,energy policy makers and building industry...Description Journal of Building Energy Efficiency(monthly),initiated in October 2006,supplies a platform for architects,mechanicalengineers,civil engineers,energy researchers,energy policy makers and building industry to communicate on investigations,innovation,research and development of energy efficiency in buildings.The Journal has been classified into the“Catalog of High-quality Sci-Tech Journals of Building Science(2020,T3)”by the Architectural Society of China(ASC),certificated as the“Source Journal for Chinese Scientificand Technical Papers and Citations”by Institute of Scientific and Technical Information of China(ISTIC)since 2013and the“China Core Academic Journal of RCCSE”by Library of Wuhan University and other cooperating institutes since 2014.展开更多
Objective:To investigate the potential link between chromosomal polymorphisms in couples who had a medical history of idiopathic recurrent pregnancy loss.Methods:Cytogenetic investigation was conducted with mitogen(Ph...Objective:To investigate the potential link between chromosomal polymorphisms in couples who had a medical history of idiopathic recurrent pregnancy loss.Methods:Cytogenetic investigation was conducted with mitogen(Phytohemagglutinin-M,Gibco)stimulated blood T lymphocytes by Giemsa trypsin Giemsa banding and Ag-NOR banding on 580 couples with a history of idiopathic recurrent pregnancy loss and 240 couples from the general population.Thirty good chromosomal spreads were captured,karyotyped,and analyzed.The karyotypes were designated using the International System for Human Cytogenomic Nomenclature 2024.Pearson Chi-square test was used to compare the frequency of chromosomal polymorphism variations in the idiopathic recurrent pregnancy loss group with the general population group.Results:A conventional cytogenetic investigation revealed that 45.43%of couples experiencing idiopathic recurrent pregnancy loss presented with various types of chromosomal polymorphic variants,compared to 11.88%in the general population.The overall frequency of these chromosomal polymorphic variants was significantly higher in the idiopathic recurrent pregnancy loss group compared to the general population group(OR 9.97,95%CI 6.99-14.21;P<0.05).Additionally,the prevalence of polymorphic variants was higher among males(49.14%)than females(41.72%)(P=0.01).Conclusions:Chromosomal polymorphic analysis may play a crucial role in the assessment and careful clinical management of cases with idiopathic recurrent pregnancy loss,especially when no other conclusive reasons are identified during the initial evaluation.Therefore,heteromorphism should not be overlooked while investigating the causes of idiopathic recurrent pregnancy loss.展开更多
Since the view that the localized rail third-order bending mode can cause high-order polygonization(mainly 18-23)of high-speed train wheels was put forward in 2017,many scholars have attempted to link a connection bet...Since the view that the localized rail third-order bending mode can cause high-order polygonization(mainly 18-23)of high-speed train wheels was put forward in 2017,many scholars have attempted to link a connection between the localized rail bending modes and wheel polygonization phenomenon and polygonal wheel passing frequency.This paper first establishes a flexible track model considering the structural and parametric characteristics of fasteners,verifies the model by using vehicle tracking test data,then investigates the influence of fastener parameter matching on the localized rail bending modes,and obtains the following conclusions:(1)There is nearly a 1:1 mapping relationship between the localized rail bending modal frequency and polygonal wheel passing(PWP)frequency,which supports that the localized rail bending mode is one of the causes of wheel polygonization.(2)The iron plate of the fastener system plays a role of dynamic vibration absorber in the vehicle-rail coupled system,and the fastener parameters significantly influence the localized rail bending modal vibration.Finally,this paper proposes a design principle of a high-frequency vibration-absorbing fastener,which provides a feasible solution to mitigate the localized rail bending modal vibration and high-order wheel polygonization.Meanwhile,it points out that this measure may induce other high-frequency vibration problems,e.g.,aggravating modal vibration above 800 Hz.Further,this paper proposes a concept of differentiated arrangement of fasteners,suggesting that different high-frequency vibration-absorbing fasteners be installed in different sections of the whole line to make the localized rail bending modal frequency of the whole line disordered,thus disrupting and further mitigating the development of the wheel polygonization.展开更多
Large-volume presses(LVPs)are widely utilized in diverse research fields—including high-pressure physics,chemistry,materials science,and Earth and planetary sciences—to investigate the physical and chemical properti...Large-volume presses(LVPs)are widely utilized in diverse research fields—including high-pressure physics,chemistry,materials science,and Earth and planetary sciences—to investigate the physical and chemical properties of materials under extreme high-pressure and hightemperature conditions.A prerequisite for achieving reproducible property measurements is the determination and control of pressure within experimental setups.However,the lack of precise pressure calibration in LVPs hinders the broader application of such devices in ultrahigh-pressure studies.This study employs a suite of standard phase transition-based pressure markers—comprising metallic conductors,semiconductors,and minerals—through both in situ and ex situ identification approaches,to establish pressure calibration curves ranging from 0.4 to>30 GPa for various types of LVP installed at the Center for High Pressure Science and Technology Advanced Research(HPSTAR),Beijing,including piston–cylinder,cubic,and multi-anvil presses.The results provide a unified and traceable pressure reference for highpressure experiments conducted at HPSTAR,while also offering technical guidance and calibration standards for other researchers utilizing similar LVP systems,thereby enabling more consistent comparison between different laboratories.This work facilitates the advancement of LVP research toward broader applications in higher-pressure regimes.展开更多
Defence Technology(ISSN 2214-9147(O);2096-3459(P)),sponsored by China Ordnance Society,is published monthly and aims to become one of the well-known comprehensive journals in the world,which reports on the breakthroug...Defence Technology(ISSN 2214-9147(O);2096-3459(P)),sponsored by China Ordnance Society,is published monthly and aims to become one of the well-known comprehensive journals in the world,which reports on the breakthroughs in defence technology by building up an international academic exchange platform for the defence technology related research.It publishes original research papers having direct bearing on defence,with a balanced coverage on analytical,experimental,numerical simulation and applied investigations.It covers various disciplines of science,technology and engineering.展开更多
Multi-organ-on-a-chip(MOOC)technology represents a pivotal direction in the organ-on-a-chip field,seeking to emulate the complex interactions of multiple human organs in vitro through microfluidic systems.This technol...Multi-organ-on-a-chip(MOOC)technology represents a pivotal direction in the organ-on-a-chip field,seeking to emulate the complex interactions of multiple human organs in vitro through microfluidic systems.This technology overcomes the limitations of traditional single-organ models,providing a novel platform for investigating complex disease mechanisms and evaluating drug efficacy and toxicity.Although it demonstrates broad application prospects,its development still faces critical bottlenecks,including inadequate physiological coupling between organs,short functional maintenance durations,and limited real-time monitoring capabilities.Contemporary research is advancing along three key directions,including functional coupling,sensor integration,and full-process automation systems,to propel the technology toward enhanced levels of physiological relevance and predictive accuracy.展开更多
The composite structures/components made by friction stir lap welding(FSLW)of Mg alloy sheet and Al alloy sheet are of wide application potentials in the manufacturing sector of transportation vehicles.To further impr...The composite structures/components made by friction stir lap welding(FSLW)of Mg alloy sheet and Al alloy sheet are of wide application potentials in the manufacturing sector of transportation vehicles.To further improve the joint quality,the ultrasonic vibration(UV)is exerted in FSLW,and the UV enhanced FSLW(UVeFSLW)was developed for making Mg-to-Al dissimilar joints.The numerical analysis and experimental investigation were combined to study the process mechanism in Mg/Al UVeFSLW.An equation related to the temperature and strain rate was derived to calculate the grain size at different locations of the weld nugget zone,and the effect of grain size distribution on the threshold thermal stress was included,so that the prediction accuracy of flow stress was further improved.With such modified constitutive equation,the numerical simulation was conducted to compare the heat generation,temperature profiles and material flow behaviors in Mg/Al UVeFSLW/FSLW processes.It was found that the exerted UV decreased the temperature at two checking points on the tool/workpiece interface from 707/671 K in FSLW to 689/660 K in UVeFSLW,which suppressed the IMCs thickness at Mg-Al interface from 1.7μm in FSLW to 1.1μm in UVeFSLW.The exerted UV increased the horizontal materials flow ability,and decreased the upward flow ability,which resulted in the increase of effective sheet thickness/effective lap width from 2.01/3.70 mm in FSLW to 2.04/4.84 mm in UVeFSLW.Therefore,the ultrasonic vibration improved the tensile shear strength of Mg-to-Al lap joints by 18%.展开更多
Scientific and technological advancements are rapidly transforming underground engineering,shifting from labor-intensive,time-consuming methods to automated,real-time systems.This timely and comprehensive review cover...Scientific and technological advancements are rapidly transforming underground engineering,shifting from labor-intensive,time-consuming methods to automated,real-time systems.This timely and comprehensive review covers in-situ testing,intelligent monitoring,and geophysical testing methods,highlighting fundamental principles,testing apparatuses,data processing techniques,and engineering applications.The state-of-the-art summary emphasizes not only cutting-edge innovations for complex and harsh environments but also the transformative role of artificial intelligence and machine learning in data interpretations.The integration of big data and advanced algorithms is particularly impactful,enabling the identification,prediction,and mitigation of potential risks in underground projects.Key aspects of the discussion include detection capabilities,method integration,and data convergence of intelligent technologies to drive enhanced safety,operational efficiency,and predictive reliability.The review also examines future trends in intelligent technologies,emphasizing unified platforms that combine multiple methods,real-time data,and predictive analytics.These advancements are shaping the evolution of underground construction and maintenance,aiming for risk-free,high-efficiency underground engineering.展开更多
BACKGROUND Gestational diabetes mellitus(GDM)is a growing public health concern,particularly in regions with diverse ethnic populations.Understanding the incidence and risk factors of GDM is crucial for early preventi...BACKGROUND Gestational diabetes mellitus(GDM)is a growing public health concern,particularly in regions with diverse ethnic populations.Understanding the incidence and risk factors of GDM is crucial for early prevention and management,especially in underrepresented areas like Guizhou Province,China,where geographic and ethnic diversity may influence the disease’s prevalence and risk profiles.AIM To investigate the incidence of GDM and identify its associated risk and protective factors among different ethnic groups in Guizhou Province,providing essential data for early prevention strategies.METHODS A multi-center retrospective study was conducted,dividing participants into GDM and non-GDM groups according to standardized diagnostic criteria.Data were collected from 103629 deliveries across 40 hospitals in Guizhou.Various demographic,clinical,and laboratory parameters were analyzed using logistic regression to identify risk and protective factors for GDM.RESULTS Among the 103629 deliveries,18957 cases of GDM were identified,with an incidence of approximately 18.3%.The risk of GDM was higher in the Han ethnic group compared to minority ethnic groups.The Dong ethnic group had the lowest incidence among the minorities.Key risk factors identified included older age(especially>35 years),higher pre-pregnancy body mass index(BMI),light physical activity,gravidity,family history of diabetes,hemoglobin,aspartate aminotransferase,alanine aminotransferase,and direct bilirubin.Protective factors included higher education level,total protein,and albumin.There were also differences based on blood type,with type A associated with higher risk.CONCLUSION The incidence rate in Guizhou is 18.3%.Older age(especially>35 years),Han ethnicity,lower education level,higher pre-pregnancy BMI,light physical activity,and higher gravidity are the main risk factors for GDM.Laboratory findings indicate that higher hemoglobin,higher liver function parameters(alanine aminotransferase,aspartate aminotransferase,and direct bilirubin),and lower total protein and albumin are associated with a higher risk of GDM.Blood type A has a higher risk of GDM compared to blood types AB and O.展开更多
The growth of computing power in data centers(DCs)leads to an increase in energy consumption and noise pollution of air cooling systems.Chip-level cooling with high-efficiency coolant is one of the promising methods t...The growth of computing power in data centers(DCs)leads to an increase in energy consumption and noise pollution of air cooling systems.Chip-level cooling with high-efficiency coolant is one of the promising methods to address the cooling challenge for high-power devices in DCs.Hybrid nanofluid(HNF)has the advantages of high thermal conductivity and good rheological properties.This study summarizes the numerical investigations of HNFs in mini/micro heat sinks,including the numerical methods,hydrothermal characteristics,and enhanced heat transfer technologies.The innovations of this paper include:(1)the characteristics,applicable conditions,and scenarios of each theoretical method and numerical method are clarified;(2)the molecular dynamics(MD)simulation can reveal the synergy effect,micro motion,and agglomeration morphology of different nanoparticles.Machine learning(ML)presents a feasiblemethod for parameter prediction,which provides the opportunity for the intelligent regulation of the thermal performance of HNFs;(3)the HNFs flowboiling and the synergy of passive and active technologies may further improve the overall efficiency of liquid cooling systems in DCs.This review provides valuable insights and references for exploring the multi-phase flow and heat transport mechanisms of HNFs,and promoting the practical application of HNFs in chip-level liquid cooling in DCs.展开更多
One of the detection objectives of the Chinese Asteroid Exploration mission is to investigate the space environment near the Main-belt Comet(MBC,Active Asteroid)311P/PANSTARRS.This paper outlines the scientific object...One of the detection objectives of the Chinese Asteroid Exploration mission is to investigate the space environment near the Main-belt Comet(MBC,Active Asteroid)311P/PANSTARRS.This paper outlines the scientific objectives,measurement targets,and measurement requirements for the proposed Gas and Ion Analyzer(GIA).The GIA is designed for in-situ mass spectrometry of neutral gases and low-energy ions,such as hydrogen,carbon,and oxygen,in the vicinity of 311P.Ion sampling techniques are essential for the GIA's Time-of-Flight(TOF)mass analysis capabilities.In this paper,we present an enhanced ion sampling technique through the development of an ion attraction model and an ion source model.The ion attraction model demonstrates that adjusting attraction grid voltage can enhance the detection efficiency of low-energy ions and mitigate the repulsive force of ions during sampling,which is influenced by the satellite's surface positive charging.The ion source model simulates the processes of gas ionization and ion multiplication.Simulation results indicate that the GIA can achieve a lower pressure limit below 10-13Pa and possess a dynamic range exceeding 10~9.These performances ensure the generation of ions with stable and consistent current,which is crucial for high-resolution and broad dynamic range mass spectrometer analysis.Preliminary testing experiments have verified GIA's capability to detect gas compositions such as H2O and N2.In-situ measurements near 311P using GIA are expected to significantly contribute to our understanding of asteroid activity mechanisms,the evolution of the atmospheric and ionized environments of main-belt comets,the interactions with solar wind,and the origin of Earth's water.展开更多
0 INTRODUCTION Geohazards in mountainous regions pose significant risks to the construction and safe operation of transportation,water conservancy,and other critical infrastructure projects.Engineering geological inve...0 INTRODUCTION Geohazards in mountainous regions pose significant risks to the construction and safe operation of transportation,water conservancy,and other critical infrastructure projects.Engineering geological investigations are crucial for disaster prevention and mitigation.展开更多
Polyploidization is a commonly employed strategy in crop breeding to augment genetic diversity,particularly leveraging the distinctive benefits of additional progressive heterosis or multi-generation heterosis unique ...Polyploidization is a commonly employed strategy in crop breeding to augment genetic diversity,particularly leveraging the distinctive benefits of additional progressive heterosis or multi-generation heterosis unique to polyploidy.Despite genetic disparities between polyploids and diploids,challenges stem from reproductive anomalies,complicating genetic investigations in polyploid systems.Through nearly two decades of intensive research,our team has effectively generated a series of fertile tetraploid lines known as neo-tetraploid rice(NTR),facilitating comparative genetic studies between diploid and tetraploid rice.In this study,we identified diploid counterparts(H3d and H8d)for two NTR lines[Huaduo 3(H3)and Huaduo 8(H8)]and utilized them to create diploid and tetraploid fertile F_(2) populations to assess genotype segregation ratios,recombination rates,and their impact on QTL mapping via bulked segregant analysis combined with sequencing(BSA-seq).Additionally,we assessed yield heterosis in F_(1) and F_(2) generations of two tetraploid populations(H3×H8 and T449×H1),revealing evidence of multi-generation heterosis in polyploid rice.These findings provide valuable insights into the advantages and challenges of polyploid rice breeding.展开更多
基金Supported by Vision International Eye Missions-USA,“One Drop for All”,Italy,and Private Donors in the Netherlands.
文摘AIM:To ascertain the pattern of ocular morbidity in a population of primary school children in rural Kenya as it is a prerequisite for planning effective preventive and therapeutic strategies.METHODS:A cross-sectional survey of ocular symptoms and clinical eye examinations were performed in a sample of 35 rural primary schools in the semi-arid region of Kajiado West sub-county in S.W.Kenya,amongst a seminomadic tribe(Maasai).Students in Grades 1-8 were included.Visual acuity was measured using the Snellen“tumbling E”chart at 6 m.Children with symptoms of refractive error underwent non-cycloplegic refraction.RESULTS:A total of 2036 children(1084 males)between the ages of 4-20y were examined.Conjunctival actinic changes were present in 22%(442/2036).Nine cases were seen with a potential squamous carcinoma.No overt classical ocular signs of vitamin A deficiency were noted,although 181(8.9%)children complained of nyctalopia.Three hundred thirty-six(16.5%)children had a visual acuity worse than 6/12 in either eye,were unable to read N10 near text at 40 cm or had symptoms suggestive of refractive error.Refractive data led to an estimate of hyperopia of+1.00 D or more in 3.9%and of myopia of-0.50 D or more in either eye in 3.0%of the study population.CONCLUSION:Solar exposure-and dust-related conjunctival pathology is common.As this may develop into potentially sight-or even life-threatening conditions,it warrants further study,and preventive strategies may be needed.Complaints of nyctalopia were common and could suggest vitamin A deficiency.The prevalence of refractive errors is low in this rural African population.
基金supported by the National Key R&D Plan of the Ministry of Science and Technology,China(2018YFA0903101,2018YFD0900302)the Key Program of Frontier Sciences of the Chinese Academy of Sciences(KJZD-SW-L11).
文摘Aquatic viruses are naturally present in the aquatic environment and the number of viruses is staggering.Various multicellular organisms in aquatic ecosystems may be infected,cross-species transmitted,manipulated,and killed by aquatic viruses,which can lead to cascading ecological effects.The viruses in unicellular aquatic organisms can alter interactions between host individuals,and are essential in effecting or maintaining the dynamics of aquatic microbial communities,horizontal gene transfer,biodiversity,and modulating ecological processes globally.Meanwhile,hosts also impact viral abundance and diversity.Microbial diversity drives multifunctionality in ecosystems,while viruses shape complex microbial communities and are crucial for ecosystem functioning.This review focuses on molecular,genetic,evolutionary,and ecosystemic advances related to emerging and reemerging aquatic viruses,presents the contexts,novel tools,and investigative approaches pertaining to the study of aquatic virology,and discusses the mechanisms by which viruses affect aquatic ecosystems.The paper provides an efficient and broadly-based blueprint for improving understanding of aquatic viruses.
基金This work is supported by the Public Security First-class Discipline Cultivation and Public Safety Behavioral Science Lab Project(No.2023ZB02)the National Natural Science Foundation of China(72274208).
文摘Investigative identification is a routine criminal investigative procedure,the results of which can be used as evidence in litigation.However,some suspects often deny their involvement in the case,and some witnesses may withhold information or misrepresent it,all of which may lead to a miscarriage of justice.This study created a stressful environment and conducted a simulated crime experiment to explore whether eye movement data can be an effective feature for distinguishing perpetrators,innocents,and insiders.The eye movement features—such as the total fixation duration,number of fixations,and first fixation duration—within an area of interest were collected from 83 participants sorted into informed,involved,and innocent groups.The results revealed the following:(1)compared with the object and scene stimuli,subjects with different identities were more likely to exhibit significant differences in eye movement data for the involved and irrelevant portraits.The total fixation duration and the number of fixations can provide a reference for judging whether someone is involved in a case,and the first fixation duration effect was not obvious.(2)Using machine learning algorithms to predict subjects’identities through eye movement features,it was demonstrated that the involved portrait-object-scene model had the best predictive effect.(3)Multiple algorithmic models were used to distinguish subjects’identities,and the highest accuracy of 92.7%was achieved for the informed×innocent group,88%for the innocent×suspect group(including the informed and involved groups),and 84.5%for the involved group.The eye movement analysis method can provide a reference for criminal investigators to distinguish between the perpetrator,insider,and innocent,and offer a novel approach to determining the direction of further investigation and uncovering and verifying case clues.
基金financially supported by the Natural Science Foundation of Jiangsu Province,China(No.BK 20221502)the National Natural Science Foundation of China(No.42477147)。
文摘In this research,a comparative analysis was conducted on the performance and efficiency of the dual-anchor soft robot(DASR)and the extension-contraction soft robot(ECSR).These robots were constructed by imitating the locomotion of razor clams.The penetration force for extension actuators and the anchorage force for expansion actuators in dry sand with distinct relative densities were tested by differentiating input air pressure and length-to-diameter ratios(λ).On the basis of the findings,a DASR and an ECSR were developed.DASR comprised two expansion actuators as the head and the tail segments at two ends,and one extension actuator as the middle segment.ECSR was composed of an extension actuator.A method based on the force equilibrium was introduced to ascertain and adjust the geometric parameters(length of each segment)of DASR.The burrowing-out performance and efficiency of DASR and ECSR in sands with distinct relative densities were explored.The results revealed that DASR exhibited high efficiency in dense sand in terms of lower time of burrowing-out,slip-to-advancement ratio,and cost of transport.ECSR might perform better in looser sand in terms of higher average burrowing-out velocity,higher advancement in each cycle,and lower energy consumption.However,it had larger slips than DASR.DASR could realize steady advancement and net displacement in each cycle and effectively decrease slips.These findings demonstrate the benefits and usability of the dual-anchor motion and offer new insights into the application of the dual-anchor mechanism in the burrowing of robots.
基金mainly supported by the Natural Science Foundation of China (Grant Nos. 52288102, 52090020, and 52372261)the Natural Science Foundation of Hebei Province (Grant No. E202403045)+1 种基金the S&T Program of Hebei (Grant No. 225A1102D)the Ministry of Education Chang Jiang Scholar Professor Program (Grant No. T2022241)
文摘Recent advances in geoscience have underscored the critical role of abiogenic processes in petroleum formation,especially the formation and polymerization of methane.However,whether a direct carbon-H_(2) reaction can produce C_(2+)hydrocarbons(e.g.,ethane and propane)beyond methane remains an open question.Here,we demonstrate the direct synthesis of ethane and propane via reactions between amorphous carbon and H_(2) under upper mantle conditions(2-10 GPa and 800-1200℃).A systematic investigation reveals that increasing structural disorder in carbon precursors,from graphite to glassy carbon-Ⅱ and carbon black,enhances the production of C_(2)-C_(3) hydrocarbons.Through integrated X-ray diffraction and reverse Monte Carlo simulations,we establish that the continuous random atomic network structures in amorphous carbon enable one-step synthesis of heavy hydrocarbons with H_(2).These models establish a direct link between atomic-scale carbon structures and the one-step synthesis of C_(2+) hydrocarbons under H_(2)-rich,high-pressure,and high-temperature conditions—potentially revealing an efficient mechanism for the abiotic production of C_(2+) hydrocarbons in the upper mantle.
文摘Description Journal of Building Energy Efficiency(monthly),initiated in October 2006,supplies a platform for architects,mechanical engineers,civil engineers,energy researchers,energy policy makers and building industry to communicate on investigations,innovation,research and development of energy efficiency in buildings.The Journal has been classified into the“Catalog of High-quality Sci-Tech Journals of Building Science(2020,T3)”by the Architectural Society of China(ASC),certificated as the“Source Journal for Chinese Scientific and Technical Papers and Citations”by Institute of Scientific and Technical Information of China(ISTIC)since 2013 and the“China Core Academic Journal of RCCSE”by Library of Wuhan University and other cooperating institutes since 2014.
文摘Description Journal of Building Energy Efficiency(monthly),initiated in October 2006,supplies a platform for architects,mechanicalengineers,civil engineers,energy researchers,energy policy makers and building industry to communicate on investigations,innovation,research and development of energy efficiency in buildings.The Journal has been classified into the“Catalog of High-quality Sci-Tech Journals of Building Science(2020,T3)”by the Architectural Society of China(ASC),certificated as the“Source Journal for Chinese Scientificand Technical Papers and Citations”by Institute of Scientific and Technical Information of China(ISTIC)since 2013and the“China Core Academic Journal of RCCSE”by Library of Wuhan University and other cooperating institutes since 2014.
基金funded by the Technology Development Board(TDB)of India's Ministry of Science and Technology(TDB/M-25/2018-19).
文摘Objective:To investigate the potential link between chromosomal polymorphisms in couples who had a medical history of idiopathic recurrent pregnancy loss.Methods:Cytogenetic investigation was conducted with mitogen(Phytohemagglutinin-M,Gibco)stimulated blood T lymphocytes by Giemsa trypsin Giemsa banding and Ag-NOR banding on 580 couples with a history of idiopathic recurrent pregnancy loss and 240 couples from the general population.Thirty good chromosomal spreads were captured,karyotyped,and analyzed.The karyotypes were designated using the International System for Human Cytogenomic Nomenclature 2024.Pearson Chi-square test was used to compare the frequency of chromosomal polymorphism variations in the idiopathic recurrent pregnancy loss group with the general population group.Results:A conventional cytogenetic investigation revealed that 45.43%of couples experiencing idiopathic recurrent pregnancy loss presented with various types of chromosomal polymorphic variants,compared to 11.88%in the general population.The overall frequency of these chromosomal polymorphic variants was significantly higher in the idiopathic recurrent pregnancy loss group compared to the general population group(OR 9.97,95%CI 6.99-14.21;P<0.05).Additionally,the prevalence of polymorphic variants was higher among males(49.14%)than females(41.72%)(P=0.01).Conclusions:Chromosomal polymorphic analysis may play a crucial role in the assessment and careful clinical management of cases with idiopathic recurrent pregnancy loss,especially when no other conclusive reasons are identified during the initial evaluation.Therefore,heteromorphism should not be overlooked while investigating the causes of idiopathic recurrent pregnancy loss.
基金supported by the National Natural Science Foundation of China(Grant Nos.:52202423,U2268211,and 52475136)the China Postdoctoral Science Foundation(Grant Nos.:2022M712636 and 2023T160546)+1 种基金the Natural Science Foundation of Sichuan Province(Grant No.:2025ZNSFSC0398)the Independent R&D Project of the State Key Laboratory of Traction Power(Grant No.:2023TPL-T14).
文摘Since the view that the localized rail third-order bending mode can cause high-order polygonization(mainly 18-23)of high-speed train wheels was put forward in 2017,many scholars have attempted to link a connection between the localized rail bending modes and wheel polygonization phenomenon and polygonal wheel passing frequency.This paper first establishes a flexible track model considering the structural and parametric characteristics of fasteners,verifies the model by using vehicle tracking test data,then investigates the influence of fastener parameter matching on the localized rail bending modes,and obtains the following conclusions:(1)There is nearly a 1:1 mapping relationship between the localized rail bending modal frequency and polygonal wheel passing(PWP)frequency,which supports that the localized rail bending mode is one of the causes of wheel polygonization.(2)The iron plate of the fastener system plays a role of dynamic vibration absorber in the vehicle-rail coupled system,and the fastener parameters significantly influence the localized rail bending modal vibration.Finally,this paper proposes a design principle of a high-frequency vibration-absorbing fastener,which provides a feasible solution to mitigate the localized rail bending modal vibration and high-order wheel polygonization.Meanwhile,it points out that this measure may induce other high-frequency vibration problems,e.g.,aggravating modal vibration above 800 Hz.Further,this paper proposes a concept of differentiated arrangement of fasteners,suggesting that different high-frequency vibration-absorbing fasteners be installed in different sections of the whole line to make the localized rail bending modal frequency of the whole line disordered,thus disrupting and further mitigating the development of the wheel polygonization.
基金supported by the National Science Foundation of China(Grant Nos.U1530402 and U1930401).
文摘Large-volume presses(LVPs)are widely utilized in diverse research fields—including high-pressure physics,chemistry,materials science,and Earth and planetary sciences—to investigate the physical and chemical properties of materials under extreme high-pressure and hightemperature conditions.A prerequisite for achieving reproducible property measurements is the determination and control of pressure within experimental setups.However,the lack of precise pressure calibration in LVPs hinders the broader application of such devices in ultrahigh-pressure studies.This study employs a suite of standard phase transition-based pressure markers—comprising metallic conductors,semiconductors,and minerals—through both in situ and ex situ identification approaches,to establish pressure calibration curves ranging from 0.4 to>30 GPa for various types of LVP installed at the Center for High Pressure Science and Technology Advanced Research(HPSTAR),Beijing,including piston–cylinder,cubic,and multi-anvil presses.The results provide a unified and traceable pressure reference for highpressure experiments conducted at HPSTAR,while also offering technical guidance and calibration standards for other researchers utilizing similar LVP systems,thereby enabling more consistent comparison between different laboratories.This work facilitates the advancement of LVP research toward broader applications in higher-pressure regimes.
文摘Defence Technology(ISSN 2214-9147(O);2096-3459(P)),sponsored by China Ordnance Society,is published monthly and aims to become one of the well-known comprehensive journals in the world,which reports on the breakthroughs in defence technology by building up an international academic exchange platform for the defence technology related research.It publishes original research papers having direct bearing on defence,with a balanced coverage on analytical,experimental,numerical simulation and applied investigations.It covers various disciplines of science,technology and engineering.
基金supported by the Shenzhen Medical Research Fund(Grant No.A2303049)Guangdong Basic and Applied Basic Research(Grant No.2023A1515010647)+1 种基金National Natural Science Foundation of China(Grant No.22004135)Shenzhen Science and Technology Program(Grant No.RCBS20210706092409020,GXWD20201231165807008,20200824162253002).
文摘Multi-organ-on-a-chip(MOOC)technology represents a pivotal direction in the organ-on-a-chip field,seeking to emulate the complex interactions of multiple human organs in vitro through microfluidic systems.This technology overcomes the limitations of traditional single-organ models,providing a novel platform for investigating complex disease mechanisms and evaluating drug efficacy and toxicity.Although it demonstrates broad application prospects,its development still faces critical bottlenecks,including inadequate physiological coupling between organs,short functional maintenance durations,and limited real-time monitoring capabilities.Contemporary research is advancing along three key directions,including functional coupling,sensor integration,and full-process automation systems,to propel the technology toward enhanced levels of physiological relevance and predictive accuracy.
基金supported by the National Natural Science Foundation of China(Grant No.52035005)the Key R&D Program of Shandong Province in China(Grant No.2021ZLGX01).
文摘The composite structures/components made by friction stir lap welding(FSLW)of Mg alloy sheet and Al alloy sheet are of wide application potentials in the manufacturing sector of transportation vehicles.To further improve the joint quality,the ultrasonic vibration(UV)is exerted in FSLW,and the UV enhanced FSLW(UVeFSLW)was developed for making Mg-to-Al dissimilar joints.The numerical analysis and experimental investigation were combined to study the process mechanism in Mg/Al UVeFSLW.An equation related to the temperature and strain rate was derived to calculate the grain size at different locations of the weld nugget zone,and the effect of grain size distribution on the threshold thermal stress was included,so that the prediction accuracy of flow stress was further improved.With such modified constitutive equation,the numerical simulation was conducted to compare the heat generation,temperature profiles and material flow behaviors in Mg/Al UVeFSLW/FSLW processes.It was found that the exerted UV decreased the temperature at two checking points on the tool/workpiece interface from 707/671 K in FSLW to 689/660 K in UVeFSLW,which suppressed the IMCs thickness at Mg-Al interface from 1.7μm in FSLW to 1.1μm in UVeFSLW.The exerted UV increased the horizontal materials flow ability,and decreased the upward flow ability,which resulted in the increase of effective sheet thickness/effective lap width from 2.01/3.70 mm in FSLW to 2.04/4.84 mm in UVeFSLW.Therefore,the ultrasonic vibration improved the tensile shear strength of Mg-to-Al lap joints by 18%.
基金supported by Ministry of Education of Singapore,under Academic Research Fund Tier 1(Grant Number RG143/23).
文摘Scientific and technological advancements are rapidly transforming underground engineering,shifting from labor-intensive,time-consuming methods to automated,real-time systems.This timely and comprehensive review covers in-situ testing,intelligent monitoring,and geophysical testing methods,highlighting fundamental principles,testing apparatuses,data processing techniques,and engineering applications.The state-of-the-art summary emphasizes not only cutting-edge innovations for complex and harsh environments but also the transformative role of artificial intelligence and machine learning in data interpretations.The integration of big data and advanced algorithms is particularly impactful,enabling the identification,prediction,and mitigation of potential risks in underground projects.Key aspects of the discussion include detection capabilities,method integration,and data convergence of intelligent technologies to drive enhanced safety,operational efficiency,and predictive reliability.The review also examines future trends in intelligent technologies,emphasizing unified platforms that combine multiple methods,real-time data,and predictive analytics.These advancements are shaping the evolution of underground construction and maintenance,aiming for risk-free,high-efficiency underground engineering.
基金National Natural Science Foundation of China,No.81960284Science and Technology Support Program of Science and Technology Department of Guizhou Province,No.Qian Ke He Zhi Cheng[2022]Yi Ban 183.
文摘BACKGROUND Gestational diabetes mellitus(GDM)is a growing public health concern,particularly in regions with diverse ethnic populations.Understanding the incidence and risk factors of GDM is crucial for early prevention and management,especially in underrepresented areas like Guizhou Province,China,where geographic and ethnic diversity may influence the disease’s prevalence and risk profiles.AIM To investigate the incidence of GDM and identify its associated risk and protective factors among different ethnic groups in Guizhou Province,providing essential data for early prevention strategies.METHODS A multi-center retrospective study was conducted,dividing participants into GDM and non-GDM groups according to standardized diagnostic criteria.Data were collected from 103629 deliveries across 40 hospitals in Guizhou.Various demographic,clinical,and laboratory parameters were analyzed using logistic regression to identify risk and protective factors for GDM.RESULTS Among the 103629 deliveries,18957 cases of GDM were identified,with an incidence of approximately 18.3%.The risk of GDM was higher in the Han ethnic group compared to minority ethnic groups.The Dong ethnic group had the lowest incidence among the minorities.Key risk factors identified included older age(especially>35 years),higher pre-pregnancy body mass index(BMI),light physical activity,gravidity,family history of diabetes,hemoglobin,aspartate aminotransferase,alanine aminotransferase,and direct bilirubin.Protective factors included higher education level,total protein,and albumin.There were also differences based on blood type,with type A associated with higher risk.CONCLUSION The incidence rate in Guizhou is 18.3%.Older age(especially>35 years),Han ethnicity,lower education level,higher pre-pregnancy BMI,light physical activity,and higher gravidity are the main risk factors for GDM.Laboratory findings indicate that higher hemoglobin,higher liver function parameters(alanine aminotransferase,aspartate aminotransferase,and direct bilirubin),and lower total protein and albumin are associated with a higher risk of GDM.Blood type A has a higher risk of GDM compared to blood types AB and O.
基金funded by the Science and Technology Project of Tianjin(No.24YDTPJC00680)the National Natural Science Foundation of China(No.52406191).
文摘The growth of computing power in data centers(DCs)leads to an increase in energy consumption and noise pollution of air cooling systems.Chip-level cooling with high-efficiency coolant is one of the promising methods to address the cooling challenge for high-power devices in DCs.Hybrid nanofluid(HNF)has the advantages of high thermal conductivity and good rheological properties.This study summarizes the numerical investigations of HNFs in mini/micro heat sinks,including the numerical methods,hydrothermal characteristics,and enhanced heat transfer technologies.The innovations of this paper include:(1)the characteristics,applicable conditions,and scenarios of each theoretical method and numerical method are clarified;(2)the molecular dynamics(MD)simulation can reveal the synergy effect,micro motion,and agglomeration morphology of different nanoparticles.Machine learning(ML)presents a feasiblemethod for parameter prediction,which provides the opportunity for the intelligent regulation of the thermal performance of HNFs;(3)the HNFs flowboiling and the synergy of passive and active technologies may further improve the overall efficiency of liquid cooling systems in DCs.This review provides valuable insights and references for exploring the multi-phase flow and heat transport mechanisms of HNFs,and promoting the practical application of HNFs in chip-level liquid cooling in DCs.
基金Supported by the National Natural Science Foundation of China(42474239,41204128)China National Space Administration(Pre-research project on Civil Aerospace Technologies No.D010301)Strategic Priority Research Program of the Chinese Academy of Sciences(XDA17010303)。
文摘One of the detection objectives of the Chinese Asteroid Exploration mission is to investigate the space environment near the Main-belt Comet(MBC,Active Asteroid)311P/PANSTARRS.This paper outlines the scientific objectives,measurement targets,and measurement requirements for the proposed Gas and Ion Analyzer(GIA).The GIA is designed for in-situ mass spectrometry of neutral gases and low-energy ions,such as hydrogen,carbon,and oxygen,in the vicinity of 311P.Ion sampling techniques are essential for the GIA's Time-of-Flight(TOF)mass analysis capabilities.In this paper,we present an enhanced ion sampling technique through the development of an ion attraction model and an ion source model.The ion attraction model demonstrates that adjusting attraction grid voltage can enhance the detection efficiency of low-energy ions and mitigate the repulsive force of ions during sampling,which is influenced by the satellite's surface positive charging.The ion source model simulates the processes of gas ionization and ion multiplication.Simulation results indicate that the GIA can achieve a lower pressure limit below 10-13Pa and possess a dynamic range exceeding 10~9.These performances ensure the generation of ions with stable and consistent current,which is crucial for high-resolution and broad dynamic range mass spectrometer analysis.Preliminary testing experiments have verified GIA's capability to detect gas compositions such as H2O and N2.In-situ measurements near 311P using GIA are expected to significantly contribute to our understanding of asteroid activity mechanisms,the evolution of the atmospheric and ionized environments of main-belt comets,the interactions with solar wind,and the origin of Earth's water.
基金financially supported by the National Key R&D Program of China(No.2022YFC3080200)。
文摘0 INTRODUCTION Geohazards in mountainous regions pose significant risks to the construction and safe operation of transportation,water conservancy,and other critical infrastructure projects.Engineering geological investigations are crucial for disaster prevention and mitigation.
基金supported by the National Key Resarch and Development Program of China(Grant No.2023YFD1200802)the Base Bank of Lingnan Rice Germplasm Resources Project,China(Grant No.2024B1212060009).
文摘Polyploidization is a commonly employed strategy in crop breeding to augment genetic diversity,particularly leveraging the distinctive benefits of additional progressive heterosis or multi-generation heterosis unique to polyploidy.Despite genetic disparities between polyploids and diploids,challenges stem from reproductive anomalies,complicating genetic investigations in polyploid systems.Through nearly two decades of intensive research,our team has effectively generated a series of fertile tetraploid lines known as neo-tetraploid rice(NTR),facilitating comparative genetic studies between diploid and tetraploid rice.In this study,we identified diploid counterparts(H3d and H8d)for two NTR lines[Huaduo 3(H3)and Huaduo 8(H8)]and utilized them to create diploid and tetraploid fertile F_(2) populations to assess genotype segregation ratios,recombination rates,and their impact on QTL mapping via bulked segregant analysis combined with sequencing(BSA-seq).Additionally,we assessed yield heterosis in F_(1) and F_(2) generations of two tetraploid populations(H3×H8 and T449×H1),revealing evidence of multi-generation heterosis in polyploid rice.These findings provide valuable insights into the advantages and challenges of polyploid rice breeding.
