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New perspectives for investigating respiratory failure induced by cervical spinal cord injury 被引量:1
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作者 Marcel Bonay Stéphane Vinit 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第22期1949-1951,共3页
Traumatic cervical spinal cord injury (SCI), with an annual incidence of 12,000 new cases in USA (NSCISC 2013), causes devastating locomotor and respiratory paralysis and unfortunately compromises the human patien... Traumatic cervical spinal cord injury (SCI), with an annual incidence of 12,000 new cases in USA (NSCISC 2013), causes devastating locomotor and respiratory paralysis and unfortunately compromises the human patient's lifespan. The severity of the injury depends on the degree and the extent of the initial trauma. In fact, respiratory failure is the leading cause of mortality following upper cervical SCI. However, 80% of the injuries are incomplete, allowing some modest spontaneous recovery. To date, no effective treatment is available in order to restore the loss of function. 展开更多
关键词 SCI New perspectives for investigating respiratory failure induced by cervical spinal cord injury CPP
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Use of sensory substitution devices as a model system for investigating cross-modal neuroplasticity in humans 被引量:1
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作者 Amy C.Nau Matthew C.Murphy Kevin C.Chan 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第11期1717-1719,共3页
Blindness provides an unparalleled opportunity to study plasticity of the nervous system in humans.Seminal work in this area examined the often dramatic modifications to the visual cortex that result when visual input... Blindness provides an unparalleled opportunity to study plasticity of the nervous system in humans.Seminal work in this area examined the often dramatic modifications to the visual cortex that result when visual input is completely absent from birth or very early in life(Kupers and Ptito,2014).More recent studies explored what happens to the visual pathways in the context of acquired blindness.This is particularly relevant as the majority of diseases that cause vision loss occur in the elderly. 展开更多
关键词 Use of sensory substitution devices as a model system for investigating cross-modal neuroplasticity in humans BOLD
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A theoretical framework for investigating ecological problems associated with biodiversity conservation in national parks: A case of the Rwenzori Mountains National Park, Uganda
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作者 Moses Muhumuza Martie Sanders Kevin Balkwill 《Open Journal of Ecology》 2013年第2期196-204,共9页
Theoretical frameworks play a vital role in research, spelling out the constructs important in the research area, and the relationships between the constructs. An understanding of the theoretical constructs which unde... Theoretical frameworks play a vital role in research, spelling out the constructs important in the research area, and the relationships between the constructs. An understanding of the theoretical constructs which underpin the research provides researchers with a framework, which enables them to understand when, how and why particular phenomena occur. Depending on the type of research, this either allows them to make reasoned predictions, which can be empirically tested during the research or gives direction for the research if it is open-ended and exploratory. Such frameworks not only guide the questions asked and the design of the research, but also help to interpret the data. If the situation being investigated is very complex, involving numerous interlinked variables, it is often difficult to identify a single theoretical framework that is suitable for a particular study. This article uses the case of human ecological behavioural problems associated with the conservation of biodiversity in the Rwenzori Mountains National Park, to show how a theoretical framework to investigate a complex situation was developed. 展开更多
关键词 Theortical Framework ECOLOGICAL PROBLEMS BIODIVERSITY CONSERVATION investigating NATIONAL Parks Rwenzori
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Investigating “The Third Place” Identity among Chinese Language Students in Newcastle University
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作者 欧阳波 《海外英语》 2016年第22期214-216,共3页
The paper investigated"The Third Place"within Chinese language students' community in the university of Newcastle(Uo N). Through the investigation, critical analysis has been given by comparing the behav... The paper investigated"The Third Place"within Chinese language students' community in the university of Newcastle(Uo N). Through the investigation, critical analysis has been given by comparing the behaviour and performance of two types of Chinese students within the community. Moreover, critical questions have arisen: Is the teacher in the language room really the best catalyst to create"The Third Place"? How should Chinese students make use of wider context to contest their native culture? The paper further described a sociocultural framework which indicates"The Third Place"should not be an isolated knowledge to be learn, but happens through constant information exchange with the outside world and socialising. Critical applications have also been given to guide how to make"The Third Place"occur within Chinese language community smoothly. 展开更多
关键词 "The Third Place" IDENTITY SOCIOCULTURAL framework investigation inter-culture ETC
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A case study investigating the efects of emergency vaccination with Brucella abortus A19 vaccine on a dairy farm undergoing an abortion outbreak in China
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作者 Yu Wang Yan Wang +6 位作者 Qingjie Peng Zhijie Xiang Yingyu Chen Guiqiang Wang Xijuan Wu Aizhen Guo Ian D.Robertson 《Animal Diseases》 2022年第4期246-257,共12页
Brucellosis is an important zoonosis that results in substantial economic losses to the livestock industry through abortions and reduced milk yield.This study investigated an abortion outbreak in a dairy herd and then... Brucellosis is an important zoonosis that results in substantial economic losses to the livestock industry through abortions and reduced milk yield.This study investigated an abortion outbreak in a dairy herd and then explored the efects of emergency vaccination with Brucella abortus A19 vaccine on the incidence of abortion and milk yield.A full dose of vaccine(6×10^(10)—12×10^(10)colony forming units,CFU)was administered subcutaneously to calves and non-pregnant heifers,and a reduced dose(6×10^(8)—12×10^(8)CFU)to adult cows and pregnant replacement heifers.Rose Bengal Test was used to screen Brucella infection status and then positive samples were tested with a C-ELISA.Animals that tested positive for both tests were considered positive to Brucella spp.The animal-level seroprevalence of brucellosis was 23.1%(95%CI:17.0,30.2),and the attributable fraction of abortions in seropositive animals was 89.1%(95%CI:64.3,96.7).The odds of seropositivity were signifcantly higher in cows that aborted compared to cows that calved normally(OR=21.4,95%CI:4.4,168.4).Cows in sheds A2 and C1 were 10.2(95%CI:1.4,128.0)and 17.0(95%CI:2.8,190.3)times more likely to be seropositive than cows in shed B1.Antibodies were not detectable in most heifers 12 months post-vaccination.The efectiveness of the vaccine in preventing abortions was estimated to be 56.8%(95%CI:15.8,77.8)for the entire herd,but increased to 86.7%(95%CI:4.4,98.1)when only primiparous heifers were considered.Furthermore,a signifcant increase in the average herd 305-day milk yield one-year after vaccination was also observed relative to that in the previous three years.It is concluded that emergency vaccination of a dairy herd undergoing an abortion outbreak with the A19 vaccine efectively reduced the incidence of abortion and indirectly increased milk yield one-year after vaccination. 展开更多
关键词 BRUCELLOSIS Outbreak investigation Emergency vaccination Brucella abortus A19 vaccine ABORTION 305-day milk yield
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Investigating the Problems and Proposing Solutions for Rural Residential Buildings in Northwest China
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作者 Zhaobo Zhang Jianqiang Wang Mao Hu 《Journal of Architectural Research and Development》 2022年第2期8-14,共7页
With the increasing income of the rural population in Northwest China,people’s sense of happiness and gain is also increasing.However,the improvement of housing conditions is lagging behind the increasing income leve... With the increasing income of the rural population in Northwest China,people’s sense of happiness and gain is also increasing.However,the improvement of housing conditions is lagging behind the increasing income levels.In recent years,the government and owners have paid much attention to this issue.The local government has successively issued relevant guidelines and policies to encourage owners to reconstruct their houses and improve their housing conditions.Before improving housing conditions,the existing housing problems must be identified.In order to have a comprehensive and in-depth understanding of the problems of rural residential buildings in Northwest China and to propose corresponding solutions,90 representative rural residential buildings of three provinces in Northwest China have been selected for investigation,and mass data have been obtained.Upon analyzing these data,it has been found that there are problems in five aspects of rural residential buildings in Northwest China:architectural style and functional space layout,energy utilization and dissipation,design,construction,as well as structural safety and seismic measures.Valid solutions are proposed to address these problems,which can also provide a reference for the government and enterprises engaged in the architecture,engineering,and construction(AEC)industry in rural areas. 展开更多
关键词 INVESTIGATION PROBLEMS Rural residential buildings SOLUTIONS
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Analysis of the Architectural Design Talent Development Direction by Investigating the Employment Status of Architectural Design Graduates
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作者 Cuicui Qin Lijuan Xie +3 位作者 Qiliang Yu Guanhong Chen Binquan Zhang Yani Gao 《Journal of Architectural Research and Development》 2023年第6期23-28,共6页
Based on a comprehensive investigation of the employment status of architectural design graduates at a certain university,this paper analyzes the correctness of the talent development direction of architectural design... Based on a comprehensive investigation of the employment status of architectural design graduates at a certain university,this paper analyzes the correctness of the talent development direction of architectural design in hopes of pro-viding a valuable reference for further teaching reform and strengthening school-enterprise collaboration.The research re-sults show that architectural design is the main choice of graduates,accounting for as high as 63%,and traditional architec-tural design skills continue to be in demand in the market.Employment in fields such as interior design,BIM design,and green architecture is also included.The distribution of job positions for graduates is mainly in the areas of scheme design assistants and construction drawing design,requiring software operation,communication,scheme design,and construction drawing skills.This paper also proposes talent development measures such as optimizing the curriculum,strengthening faculty construction,and deepening school-enterprise collaboration,in order to improve the quality of talent development and the competitiveness of graduates. 展开更多
关键词 Employment Investigation Architectural Design Talents Development Teaching Reform
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Intelligent integration and advancement of multi-organ-on-a-chip
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作者 Chen-Xi Song Lu Huang 《Biomedical Engineering Communications》 2026年第1期1-3,共3页
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
关键词 investigating complex disease mechanisms emulate complex interactions multiple human organs vitro sensor integration intelligent integration predictive accuracy physiological coupling multi organ chip microfluidic systemsthis
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Comparison of Burrowing-Out Performance and Efficiency Between Dual-Anchor and Extension-Contraction Soft Robots
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作者 HUANG Xin HE Jia +2 位作者 WANG Hao YAN Fengyuan KOU Hailei 《Journal of Ocean University of China》 2026年第1期133-149,共17页
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
关键词 razor clam soft robots self-burrowing sand soil investigation
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Sequence-Driven Modulation of the Multistage Self-Assembly Process in Lamellin-Type β-Peptides
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作者 Imola Cs.Szigyártó Kristóf Ferentzi +5 位作者 András Wacha Kamal el Battouioui Olivér Pavela Vignesh Udyavara Nagaraj Viktor Farkas Tamás Beke-Somfai 《Aggregate》 2026年第2期391-405,共15页
Peptide-based assemblies have gained increasing attention in different areas of nanotechnology,drug delivery and molecular biology.Among these,non-natural β-peptide scaffolds are particularly promising,as their progr... Peptide-based assemblies have gained increasing attention in different areas of nanotechnology,drug delivery and molecular biology.Among these,non-natural β-peptide scaffolds are particularly promising,as their programmable and diverse secondary structures,high metabolic stability and strong self-association propensity can be easily exploited to create variable constructs.We have recently demonstrated that heterochiral,acyclic β^(3)-peptides assembled into striped lamellar nanostructures that induced antibacterial activity.The process of this assembly formation could be exploited in diverse areas,however identifying oligomerisation stages,and more importantly,controlling the spontaneous process at different levels is still lacking.In this study,a set of analogues heterochiral hexameric β^(3)-peptide sequences was investigated to understand how systematic,small variations of the sequences,such as single point mutation or N-terminal chemical modification,can influence the resulting assemblies and allow the control of formed morphologies.TEM and cryo-EM combined with molecular dynamics simulation enabled the identification and differentiation of morphological stages throughout the entire multi-step process.Depending on the position of the sequence modifications,the self-assembled structures formed small oligomers,individual protofibrils,extended,flat lamellae,bundles and macroscopic clusters.These results outline how the self-assembly process of short heterochiral β-peptides can be qualitatively fine-tuned by sequence modifications,which contribute to understanding the general peptide assembly processes for their fibrillar morphologies. 展开更多
关键词 conformational investigations controllable morphology CRYO-EM SELF-ASSEMBLY β-peptides
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Structural disorder-driven synthesis of C_(2+)hydrocarbons via direct hydrogenation of amorphous carbon with continuous random atomic networks
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作者 Shaojie Wang Mingtao Li +10 位作者 Zhongyan Wu Saichao Cao Penghui Li Xiang Zhang Zhiwei Shen Hongkai Li Ke Yang Li Zhang Guoying Gao Lin Wang Yongjun Tian 《Matter and Radiation at Extremes》 2026年第1期93-102,共10页
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
关键词 systematic investigation abiogenic processes formation polymerization HYDROGENATION amorphous carbon ETHANE structural disorder PROPANE
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Numerical Determination of Weak Adhesive Bonds Using Ultrasonic Guided Waves
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作者 EgidijusŽukauskas Damira Smagulova Elena Jasiūnienė 《Computer Modeling in Engineering & Sciences》 2026年第3期289-303,共15页
Adhesively bonded joints are widely used in modern lightweight structures due to their high strengthto-weight ratio and design flexibility.However,the reliable non-destructive evaluation of bond integrity remains a si... Adhesively bonded joints are widely used in modern lightweight structures due to their high strengthto-weight ratio and design flexibility.However,the reliable non-destructive evaluation of bond integrity remains a significant challenge.This study presents a numerical investigation of adhesively bonded joints with different adhesive properties using ultrasonic guided waves.The main focus of the investigation is to evaluate the feasibility of using guided waves to assess bond integrity,particularly for detecting challenging weak bonds.For this purpose,a theoretical analysis of dispersion curves was conducted,revealing that the S0 Lamb wave mode is significantly sensitive to variations in adhesive properties in the 300-700 kHz frequency range.Finite element modelling was used to analyse the propagation of guided waves in two scenarios:an adhesively bonded aluminum structure and a more complex configuration-adhesively bonded lap joints.The Short-Time Fourier Transform(STFT)was used to process the obtained results and determine the group velocities of guided waves.By analysing the group velocity characteristics,their dependence on the adhesive properties was identified.In the first scenario,a clear separation of S0 modes from A0 modes was observed in the STFT analysis,with a decrease in group velocity as adhesive stiffness increased.For the more complex lap joint scenario,the separation between A0 and S0 modes was less distinct.However,the analysis of the average group velocity shows a dependence of average group velocity on adhesive properties.This is similar to the first scenario.There is a decrease in average group velocity as adhesive stiffness increases.The results obtained demonstrate that guided wavebased methods have a high potential for non-destructive evaluation of adhesively bonded structures,including the detection of weak bonds. 展开更多
关键词 Adhesive joints weak bonds Lamb waves ultrasonic testing numerical investigation
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Instructions for Authors
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《建筑节能(中英文)》 2026年第1期F0003-F0003,共1页
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
关键词 mechanical engineers building industry ARCHITECTS energy efficiency energy researchers INVESTIGATIONS building energy efficiency civil engineers
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Instructions for Authors
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《建筑节能(中英文)》 2026年第3期F0003-F0003,共1页
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
关键词 mechanical engineers building industry ARCHITECTS energy efficiency energy researchers INVESTIGATIONS building energy efficiency civil engineers
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Engineered Co-O-Mo active centers for enhanced water oxidation via lattice oxygen mechanism
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作者 Fanjun Kong Heng Zhang +7 位作者 Chengjie Wang Guikai Zhang Jing Zhang Xiaorui Gao Tao Zhang Shengqi Chu Li Song Shi Tao 《Journal of Energy Chemistry》 2026年第3期946-954,共9页
Heterostructured transition-metal compounds show great potential in the oxygen evolution reaction(OER),but the reaction mechanism induced by the surface reconstruction remains unclear.Herein,we develop a kind of Co-O-... Heterostructured transition-metal compounds show great potential in the oxygen evolution reaction(OER),but the reaction mechanism induced by the surface reconstruction remains unclear.Herein,we develop a kind of Co-O-Mo active center in Co oxyhydroxide(MoCoOOH)via in situ reconstruction,which exhibits an overpotential of 275 m V at 10 mA cm^(-2)in alkaline conditions,as well as negligible deactivation after durability operation driven by a solar cell.The operando tests reveal that Mo accelerates the reconstruction from Co-Se-Mo to Co-O-Mo in MoCoOOH,which triggers the lattice oxygen activation for enhanced intrinsic OER activity.Theoretical calculations demonstrate that the Mo atoms can optimize the d-orbital energy level of Co metal atoms,adsorption-desorption oxygenated intermediates,and the rate-determining step barrier.This work gives deep insights into the oxygen-involved mechanism in the reconstructed phase and inspires the rational design of high-activity electrocatalysts in multielectron reactions. 展开更多
关键词 Surface reconstruction High-valence configuration Alkaline OER Operando investigation Lattice oxygen mechanism
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UnveilingβSubunit-Dependent Gating Defects in CaV2.1 Channelopathies:Investigation of a de novo CACNA1A Variant
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作者 Kunpeng Ma Haiyan Chen +8 位作者 Li Chen Shuainan Zhao Huafang Zou Dongfang Zou Qi Zeng Dezhi Cao Jianyuan Sun Lin Li Xuefeng Shen 《Neuroscience Bulletin》 2026年第1期215-220,共6页
Dear Editor,The Cay2.1 channel,also known as the P/Q-type Ca^(2+) channel,is a particular type of voltage-gated Ca^(2+) channel primarily expressed on the presynaptic membrane in the brain[1].It serves as an essential... Dear Editor,The Cay2.1 channel,also known as the P/Q-type Ca^(2+) channel,is a particular type of voltage-gated Ca^(2+) channel primarily expressed on the presynaptic membrane in the brain[1].It serves as an essential part of the precisely orchestrated neurotransmitter release machinery. 展开更多
关键词 de novo subunit dependent DEFECTS GATING presynaptic membrane INVESTIGATION CACNA precisely orchestrated neurotransmitter release machinery
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Instructions for Authors
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《建筑节能(中英文)》 2026年第2期F0003-F0003,共1页
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
关键词 ARCHITECTS mechanical engineers civil engineers energy researchers building industry energy efficiency INVESTIGATIONS building energy efficiency
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Epidemiological investigative report on ocular morbidity in children in rural Kenya
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作者 Marlene E.Long Lily A.Nyamai +3 位作者 Marina Marinkovic Nanda Horeweg Brian W.Fleck Martine J.Jager 《International Journal of Ophthalmology(English edition)》 2026年第1期115-122,共8页
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
关键词 ocular morbidity epidemiological investigation actinic conjunctival changes refractive error rural Kenyan children
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Association of conventional chromosomal polymorphic variants in 580 couples with idiopathic recurrent pregnancy loss:A retrospective cohort study
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作者 Sunny Kumar Jignesh Kumar Patel Amit Roy Chowdhury +2 位作者 Shagufa Sheikh Purna Chandra Mahapatra Birendranath Banerjee 《Asian pacific Journal of Reproduction》 2026年第1期11-22,共12页
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
关键词 Polymorphic variants Chromosomal anomalies Repeated pregnancy loss Cytogenetic investigation
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Influence of high-frequency vibration-absorbing fasteners on suppressing localized rail bending modal vibration
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作者 Zhecheng Tao Dadi Li +7 位作者 Lai Wei Chaozhi Ma Sheng Qu Caihong Huang Hao Gao Bin Zhu Huanyun Dai Yunguang Ye 《Railway Engineering Science》 2026年第1期159-183,共25页
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
关键词 Localized rail bending mode High-speed train Fastener system Dynamic vibration absorber Parameter investigation
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