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Reform and Practice of Bioinformatics Experimental Teaching Based on Project-based Learning:A Case Study of"Influenza Virus Analysis"
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作者 Shuying FU Linqi HUANG +2 位作者 Yu MEN Wenwu TANG Meiying FENG 《Agricultural Biotechnology》 2026年第1期5-8,12,共5页
To meet the need for cultivating application-oriented talents in local universities,this study introduced a project-based learning approach into the reform of bioinformatics experimental teaching.The course was struct... To meet the need for cultivating application-oriented talents in local universities,this study introduced a project-based learning approach into the reform of bioinformatics experimental teaching.The course was structured around a project titled"Influenza Virus Analysis",comprising four progressive modules:database utilization and information retrieval,sequence alignment and phylogenetic analysis,functional and structural prediction,and omics data analysis.These modules were integrated into a coherent research workflow that connected fragmented knowledge and technical skills.During implementation,flipped classroom and group collaboration methods were employed,alongside the establishment of a diversified assessment system emphasizing process evaluation.Teaching practice indicates that the reform effectively enhances students professional application skills,learning experience,and scientific literacy,facilitating a shift from"tool operation"to"problem-solving"capabilities.This study provides a reference model for the reform of bioinformatics experimental teaching in local universities. 展开更多
关键词 Bioinformatics experiment Project-based learning Teaching reform Teaching practice Influenza virus
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Vibrations induced by time-delayed double blastholes in underground rocks:Experimental study and theoretical analysis
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作者 Yonggang Gou Gui Yang +2 位作者 Xianyang Qiu Kun Ji Yumin Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1108-1125,共18页
Time-delayed blasting is widely utilized in engineering to mitigate induced vibration hazards and enhance fragmentation.The underlying vibration reduction principle is the decrease of the charge weight per delay,while... Time-delayed blasting is widely utilized in engineering to mitigate induced vibration hazards and enhance fragmentation.The underlying vibration reduction principle is the decrease of the charge weight per delay,while the potential for further vibration reduction remains debated,largely due to unclear underlying mechanisms.In light of the popularization of electronic detonators and the representativeness of double-hole configurationsfor multiple blastholes,it is essential to investigate the vibration characteristics induced by time-delayed double blastholes.Therefore,a series of doubleborehole experimental blasts was conducted in an underground roadway to clarify the variation in vibration from single-hole to dual-hole conditions.Based on the experimental data and inherent limitations,an exact full-fieldtheoretical model was further employed to systematically analyze the effects of delay time,charge length,and borehole inclination angle on vibrations induced by various doublehole configurations.The experimental data and theoretical analysis reveal that the general scaled distance effectively predicts vibrations in delayed blasting but does not reflectvibration reduction.Increasing delay time causes fluctuatingPPVs,which stabilize slightly above single-hole PPVs as delay times exceed a certain value.The delayed blasting primarily reduces near-fieldfrequencies.Longer charge lengths in double boreholes increase PPV levels and attenuation rates within a certain length,and the vibration behavior of combined long and short charge lengths is governed by the long blasthole.Larger blasthole inclination angles enhance vibration amplitude and reduce PPV attenuation rates.Optimizing inclination angles is more critical than adjusting delay times,and parallel boreholes offer the best vibration control. 展开更多
关键词 Vibration of double blastholes experimental data Theoretical model Delay time Wave superposition
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Experimental Study on the Compressive and Flexural Properties of the Ultrahigh-Performance Concrete Containing Fibers 被引量:1
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作者 Mohammad Yousef Nejati Manuchehr Behruyan +2 位作者 Amirreza Sadeghi Kourosh Mehdizadeh Abbasali Sadeghi 《Journal of Building Material Science》 2025年第1期83-96,共14页
Ultrahigh-performance concrete(UHPC)is a groundbreaking kind of concrete that distinguishes itself from conventional concrete through its unique material properties.Understanding and managing the time-dependent charac... Ultrahigh-performance concrete(UHPC)is a groundbreaking kind of concrete that distinguishes itself from conventional concrete through its unique material properties.Understanding and managing the time-dependent characteristics of these materials is essential for their effective use in various construction applications.This study presents an experimental evaluation of the compressive and bending properties of the UHPC incorporating polypropylene,steel,and glass fibers.Based on ACI-211 guidelines,the UHPC mix was designed by using three types of aggregates:limestone,andesite,and quartzite,along with 5%fiber content(at varying percentages of 0,5%,10%,15%,and 20%)relative to the cementitious materials,and three different water-to-cement(w/c)ratios(0.24,0.3,and 0.4)were used.In this research,the compressive and flexural strength tests were conducted.The results show that increasing the values of the fibers significantly enhances the compressive strength of the studied samples.Furthermore,the utilization of fibers markedly improves the bending strength of the samples,demonstrating a strong correlation with the yield resistance of the material.Also,findings show that using steel fibers increases the compressive and bending strength of the tested samples more than polypropylene and glass fibers.For instance,in UHPC samples with 0.4 w/c,the average compressive strength values are 82.2 MPa,70.3 MPa,and 67.1 MPa for steel,polypropylene,and glass fibers,respectively.Also,in the flexural strength test,the modulus of rupture is obtained as an average of 6.24 MPa,5.24 MPa and 4.83 MPa for UHPC samples with steel,polypropylene and glass fibers,respectively. 展开更多
关键词 experimental study Ultrahigh-Performance Concrete(UHPC) Polypropylene Fiber Steel Fiber Glass Fiber Compressive Strength Flexural Strength
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Experimental Study of a Helium Sorption Cooler with Low Temperature Fluctuation and Long Hold Time below 1 K
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作者 Tianshuo Liu Xiaoyu Cui +6 位作者 Lihao Lu Kongkuai Ying Yang Wang Kangjun Liu Zilong Wang Zhenhua Jiang Shaoshuai Liu 《Frontiers in Heat and Mass Transfer》 2025年第3期739-750,共12页
Helium sorption cooler technology is a key means to realize highly reliable low-vibration very lowtemperature environments,which have important applications in fields such as quantum computing and space exploration.Th... Helium sorption cooler technology is a key means to realize highly reliable low-vibration very lowtemperature environments,which have important applications in fields such as quantum computing and space exploration.The laboratory designed a superfluid suppression small hole and a multi-ribbed condenser,developed a reliable-performance helium sorption cooler(HSC),and conducted experimental studies.Experimental results show that the prototype can achieve the lowest cooling temperature of 873 mK without load by filling 6MPa helium at room temperature.The low-temperature hold time is 26 h,and the temperature fluctuation is within 0.8 mK.The cooling power of the helium sorption cooler is 1 mW@0.98 K@3.5 h.Experimental results indicate that when the charging pressure is reduced to 4MPa,theminimum temperature decreases to 836mK,and the hold time shortens to 16 h.When the pre-cooling temperature increases from 3.9 to 4.9 K,the hold time is reduced to 3 h. 展开更多
关键词 Helium sorption cooler low temperature condenser superfluid suppression hold time temperature fluctuation experimental study
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Role of IgE cells in the exacerbation and management of asthma:An experimental study
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作者 Agussalim Agussalim Citrawati Citrawati Adriyani Adam 《World Journal of Immunology》 2025年第1期1-7,共7页
BACKGROUND IgE plays a critical role in allergic inflammation and asthma pathogenesis.This study investigates the involvement of IgE cells in asthma exacerbation and evaluates the effectiveness of targeted interventio... BACKGROUND IgE plays a critical role in allergic inflammation and asthma pathogenesis.This study investigates the involvement of IgE cells in asthma exacerbation and evaluates the effectiveness of targeted interventions.AIM To evaluate the role of IgE in the exacerbation of allergic asthma and to determine the clinical efficacy of anti-IgE therapy in improving disease outcomes.Specifically,the study investigates changes in serum IgE levels,lung function,asthma control scores,and the frequency of acute exacerbations among patients receiving standard therapy with or without anti-IgE intervention.METHODS A total of 200 patients diagnosed with moderate to severe asthma were enrolled in this experimental study conducted from April 2024 to April 2025.Participants were randomized to receive either standard asthma therapy or therapy combined with anti-IgE agents.IgE levels and asthma control parameters were monitored.RESULTS Participants receiving anti-IgE treatment demonstrated a significant reduction in serum IgE levels(P<0.001),improved Forced expiratory volume in one second scores,and fewer exacerbation episodes compared to the control group.CONCLUSION IgE cells significantly contribute to asthma severity,and targeted therapy against IgE can improve disease outcomes.These findings underscore the importance of immunomodulatory strategies in asthma management. 展开更多
关键词 ASTHMA IGE Allergic inflammation Anti-IgE therapy experimental study
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A Novel Transcatheter Suture Closure System for Patent Foramen Ovale:An Experimental Study in Swine
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作者 Su Ye Luxi Guan +7 位作者 Dong Luo Fengwen Zhang Jianhua Lv Qizong Xie Qiao Huang Haiming Wu Haibo Hu Xiangbing Pan 《Congenital Heart Disease》 2025年第2期181-193,共13页
This study aimed to evaluate the feasibility,safety,and efficacy of a noveltranscatheter suture closure system(HaloStitch^(®))for patent foramen ovale(PFO)closure in a swine model.Methods:Thirteen swine underwent... This study aimed to evaluate the feasibility,safety,and efficacy of a noveltranscatheter suture closure system(HaloStitch^(®))for patent foramen ovale(PFO)closure in a swine model.Methods:Thirteen swine underwentexperimental PF0 model creation.All animals received implantationof the transcatheter suture closure system to evaluate procedural success.Comprehensive follow-up over sixmonths included serial ultrasound imaging,histopathological analysis,and gross anatomical exaninationof cardiac specimens.Results:Successful HaloStitch^(®)device implantation was adhieved in 11 of 13 swine.Gross anatomical examination confirrned secure positioning of all sutures in the atrial septum,with noredundancy or thrombus formation.Postoperative ultrasound demonstrated stable suture and staplepositions throughout follow-up,with no evidence of suture breakage,displacement,or thrombus.Stapleswere clearly visualized under ultrasound imaging,Both the atrial septal defect orifice diameter and residualseptal shunt flow velocity decreased significantly during the observation period.Histopathological analysisrevealed partially organized thrombi at the implant head and fibrous connective tissue encapsulation withlocalized inflammatory cell infiltration surrounding the polymer material.Conclsions:The transcathetersuture closure system(HaloStitch^(®))demonstrated feasibility,safety,and biocompatib ility for PFO closure ina swine model,supporting its potential for clinical translation. 展开更多
关键词 Patent foramen ovale transcatheter suture closure system experimental study
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Experimental Method for Studying the Effect of Dissolved Substances on the Evaporation Rate of Watwer Droplets Suspended in Air
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作者 Alexander A.Fedorets Eduard E.Kolmakov +4 位作者 Anna V.Nasyrova Dmitry N.Medvedev Vyacheslav O.Mayorov Vladimir Yu.Levashov Leonid A.Dombrovsky 《Frontiers in Heat and Mass Transfer》 2025年第4期1091-1102,共12页
A new experimental method is developed to investigate the effect of dissolved substances on the evaporation rate of small water droplets suspended in the atmosphere.The laboratory setup is based on converting a genera... A new experimental method is developed to investigate the effect of dissolved substances on the evaporation rate of small water droplets suspended in the atmosphere.The laboratory setup is based on converting a generated droplet jet of complex structure into a directed flow of evaporating droplets falling in a vertical tube.Images of falling droplets captured by a high-speed camera through a window in the vertical channel wall are used to determine the sizes and velocities of individual droplets.The computational modeling of droplet motion and evaporation proved useful at all stages of the experimental work:from selecting the position of the vertical channel to processing the experimental data.It was found that even a 0.1%mass concentration of the dissolved ionic salt KCl has a considerable effect on decreasing the evaporation rate of the droplets.In contrast,a typical fungicide with a mass concentration of 2.5%has only a slight impact on the evaporation rate.The laboratory results enabled the authors to refine the evaporation model of water droplets to account for the presence of dissolved substances.Modified models of this type are expected to be useful in controling crop spraying and also in other potential applications. 展开更多
关键词 Droplets EVAPORATION crop spraying experimental method physical model
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Experimental study on transient electromagnetic conductivity logging in cased well
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作者 Shen Yong-Jin Su Yuan-Da 《Applied Geophysics》 2025年第2期422-431,558,共11页
A cased well model consists of a coaxial tank and casing,which houses coaxially installed transmitting and receiving coils.The transmitting coil is excited by the current produced by the transmitting circuit,and trans... A cased well model consists of a coaxial tank and casing,which houses coaxially installed transmitting and receiving coils.The transmitting coil is excited by the current produced by the transmitting circuit,and transient electromagnetic responses occur in the casing,including direct coupling and casing responses.As the range between the transmitting and receiving coils increases,direct coupling responses decay rapidly,are less than the casing response at 0.3 m,and disappear at 0.7 m.By contrast,a casing response increases rapidly and then declines slowly after reaching a peak and changes little within a specifi c range.The peak decreases slowly with range.The continuous addition of water to the tank causes slight changes in transient electromagnetic responses,so the diff erence which are subtracted from the response without water is used.Moreover,the diff erences at the time of rapid increase in response and the time of rapid decrease in response are large,forming a peak and a trough.Given that the conductivity of water in a full tank changes after the addition of salt,the diff erence in the peak is linear with the increase in the conductivity of water.This result provides an experimental basis for the design of a transient electromagnetic logging instrument that measures the conductivity of formation in cased well. 展开更多
关键词 transient electromagnetic response cased well conductivity logging COIL model experiment
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Association between serum 25(OH)D levels and cancer in adults with psoriasis:A cross-sectional study 被引量:1
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作者 Lingquan Deng Yamei Gao +1 位作者 Chenxingyue Zhang Zhiqiang Yin 《Journal of Biomedical Research》 2026年第2期224-226,共3页
Dear Editor,Psoriasis,a chronic inflammatory cutaneous condition,is characterized by the development of red plaques with silvery scales,significantly affecting patients'quality of life and mental health[1].This co... Dear Editor,Psoriasis,a chronic inflammatory cutaneous condition,is characterized by the development of red plaques with silvery scales,significantly affecting patients'quality of life and mental health[1].This condition is thought to affect approximately 2%of the Western population,with diagnosis peaking in early adulthood[2].Vitamin D,a fat-soluble vitamin,is essential for phospho-calcium metabolism,calcium homeostasis,and bone health. 展开更多
关键词 serum oh d levels CANCER cross sectional study inflammatory cutaneous conditionis PSORIASIS ADULTS
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Experimental study on startup-shutdown process of a planar expansion deflection nozzle
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作者 Bocheng ZHOU Ben GUAN +2 位作者 Shuai WANG Yan CHEN Ge WANG 《Chinese Journal of Aeronautics》 2025年第7期84-98,共15页
Cold-flow experiments on planar Expansion Deflection(ED)nozzle flows are conducted under a simulated startup-shutdown process of rocket motors.The purpose is to investigate the flow and performance characteristics in ... Cold-flow experiments on planar Expansion Deflection(ED)nozzle flows are conducted under a simulated startup-shutdown process of rocket motors.The purpose is to investigate the flow and performance characteristics in ED nozzles,capture the behavior of shock flapping,and explore asymmetric flow dynamics utilizing a symmetric nozzle.A total pressure condition,characterized by rapid rise followed by a slow fall,is employed to simulate the continuous startup and shutdown processes.The schlieren imaging technique and high-frequency pressure transducers are employed to obtain the flow information.The experimental results indicate that the flow characteristics differ between the startup and shutdown processes with a hysteresis observed in the nozzle wake mode transition.During the startup process,the shock waves are pushed outward of the nozzle,while during the shutdown process,the flow propagates inward dominated by Mach stems.Counterintuitive results are demonstrated,namely,the mode transition is not the cause of the sudden thrust decrease,and the moment of maximum thrust does not coincide with the moment of maximum total pressure.During the operation of the nozzle,two stages of shock wave flapping occur,accompanied by significant wall pressure oscillations.These oscillation frequencies are demonstrated to be related to the inherent acoustic frequencies of the test chamber.An improved pressure ratio method is proposed to predict the position of the shock oscillation separation point.The prediction results revealed the shock behavior during the flapping process. 展开更多
关键词 Cold-flow experiment Expansion deflection nozzle Mode transition Shock flapping Shock waves
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Experimental Study on the Hydrodynamic Characteristics of a Convex-Type Floating Breakwater
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作者 LIANG Jia-ming LIU Yong LI Xue-yan 《China Ocean Engineering》 2025年第1期135-148,共14页
Floating breakwaters(FBs)are commonly employed for the protection of coastal installations.In this work,a convextype floating breakwater(FB)is proposed,and its hydrodynamic characteristics are studied through systemat... Floating breakwaters(FBs)are commonly employed for the protection of coastal installations.In this work,a convextype floating breakwater(FB)is proposed,and its hydrodynamic characteristics are studied through systematic laboratory experiments.Two different deck widths and two different mooring systems are set in the experiment.The transmission coefficients,reflection coefficients,motion responses and mooring forces of convex-type FBs are obtained in experiments.The influences of the deck width and mooring system on the hydrodynamic characteristics of the proposed FB are analyzed and compared.The experimental results show that the reflection coefficient and mooring force of the convex-type FB with a cross-mooring system are significantly larger than those of the convextype FB with a parallel-mooring system.A convex-type FB with a larger deck width has a higher reflection coefficient.The convex-type FBs with cross-and parallel-mooring systems have similar surge and heave motions,but the cross-mooring results in small roll motion.In addition,reliable prediction formulas for the transmission coefficient of convex-type FBs with different mooring systems have been developed,which are important for engineering design. 展开更多
关键词 experimental test convex-type floating breakwater mooring system hydrodynamic characteristic motion response mooring force
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Experimental study of postcritical deformation stage realization in layered composites during tension using digital image correlation and acoustic emission
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作者 Valeriy Wildemann Elena Strungar +2 位作者 Dmitrii Lobanov Artur Mugatarov Ekaterina Chebotareva 《Acta Mechanica Sinica》 2025年第2期163-175,共13页
Creating conditions to implement equilibrium processes of damage accumulation under a predictable scenario enables control over the failure of structural elements in critical states.It improves safety and reduces the ... Creating conditions to implement equilibrium processes of damage accumulation under a predictable scenario enables control over the failure of structural elements in critical states.It improves safety and reduces the probability of catastrophic behavior in case of accidents.Equilibrium damage accumulation in some cases leads to a falling part(called a postcritical stage)on the material’s stress-strain curve.It must be taken into account to assess the strength and deformation limits of composite structures.Digital image correlation method,acoustic emission(AE)signals recording,and optical microscopy were used in this paper to study the deformation and failure processes of an orthogonal-layup composite during tension in various directions to orthotropy axes.An elastic-plastic deformation model was proposed for the composite in a plane stress condition.The evolution of strain fields and neck formation were analyzed.The staging of the postcritical deformation process was described.AE signals obtained during tests were studied;characteristic damage types of a material were defined.The rationality and necessity of polymer composites’postcritical deformation stage taken into account in refined strength analysis of structures were concluded. 展开更多
关键词 experimental mechanics Digital image correlation method Acoustic emission Postcritical deformation Polymer composite
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Experimental and numerical study on external explosions of cylindrical versus spherical charges at tunnel entrance
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作者 Dan Luo Jinsheng Hu +4 位作者 Anbao Wang Xiao Yu Mengmeng Zhang Meili Yao Chun Li 《Defence Technology(防务技术)》 2025年第4期227-243,共17页
Most of the existing studies on tunnel blast wave are based on spherical or grouped charges, however,conventional weapons are mostly cylindrical rather than spherical. In order to analyze the impact of cylindrical cha... Most of the existing studies on tunnel blast wave are based on spherical or grouped charges, however,conventional weapons are mostly cylindrical rather than spherical. In order to analyze the impact of cylindrical charges on the tunnel blast wave loads and to develop a quantitative calculation method, this study carried out experimental and numerical research. Initially, external explosion experiments were conducted using both 35 kg spherical charges and cylindrical charges with aspect ratio of 4.8 at two different distances from the tunnel entrance. Comparative analysis of the blast wave parameters in the tunnel revealed that the explosive equivalent of the cylindrical charges was significantly higher than that of the spherical charges. To address this, an equivalent coefficient κ based on the spherical charges was proposed for the cylindrical charges. Subsequently, numerical simulations were conducted for the experimental conditions, and the numerical simulation results match the experiments well. Through numerical calculations, the reliability of the equivalent coefficient κ under the experimental conditions was verified, and comparison analysis indicated that the explosion energy of cylindrical charges spreads more radially, resulting in more explosion energy entering the tunnel, which is the fundamental reason for the increase in tunnel blast wave loads. Additionally, analyzing the explosion energy ratio entering the tunnel is an effective method for calculating the equivalent coefficient κ. Finally, through more than one hundred sets of numerical calculation results, the impact of the proportional distance λ and the ratio of charge mass to the tunnel cross-section dimension φ on the equivalence coefficients κ was investigated. An empirical formula for the equivalence coefficient κ was derived through fitting, and the accuracy of the formula was validated through literature experimental results. The research findings of this paper will provide valuable guidance for the calculation of blast wave loads in tunnel. 展开更多
关键词 Cylindrical charges Tunnel blast wave Equivalent coefficient Empirical formula Experiment and numerical simulation
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Effects of Cognitive Stimulation Intervention on Cognitive Function and Depression in Older Adults with Mild Dementia: A Quasi-Experimental Study
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作者 Ya-Wen Chang Hsiu-Chuan Chen +3 位作者 Shih-Chi Chung Wai-Lam Lao Ching-Pyng Kuo Shu-Hsin Lee 《International Journal of Mental Health Promotion》 2025年第7期979-994,共16页
Background:Cognitive stimulation therapy(CST)is a non-pharmacological intervention designed to improve cognitive function and emotional well-being in individuals with dementia.However,limited studies have evaluated it... Background:Cognitive stimulation therapy(CST)is a non-pharmacological intervention designed to improve cognitive function and emotional well-being in individuals with dementia.However,limited studies have evaluated its efficacy in Chinese-speaking populations.This study aimed to assess the effects of a 12-week cognitive stimulation interventiononcognitive functionanddepression inolder adultswithmilddementia.Methods:This quasiexperimental study employed a repeated measures design with a non-randomized experimental and control group.Participants(N=40)65 years and older with mild dementia(clinical dementia rating(CDR)=0.5–1)were recruited from a regional hospital and dementia care center in Taiwan.The experimental group(n=20)received a structured CST intervention for 12 weeks(two sessions per week,120 min per session),while the control group(n=20)received routine care.Cognitive function was assessed using the Saint Louis University Mental Status(SLUMS)exam,and depression was measured using the Chinese version of the Cornell Scale for Depression in Dementia(CSDD-C).Data were collected at baseline,4,8,and 12 weeks and analyzed using repeatedmeasures ANOVA and generalized estimating equation(GEE)modeling.Results:The experimental group showed significant improvements in cognitive function compared to the control group(SLUMS score:baseline 16.1±4.8 to 12th week 19.3±5.0,p<0.001).Depression levels decreased significantly in the experimental group but not in the control group(p<0.05).The GEE analysis showed that the improvement in cognitive function was positively associated with education level and duration,but declined with increasing age.Similarly,depression was lower in participants with higher educational levels and inmen.Conclusions:The findings support the efficacy of CST in improving cognitive function and reducing depression in older adults with mild dementia.The results highlight the importance of the duration of the intervention and individual cognitive reserve in modulating treatment outcomes. 展开更多
关键词 Cognitive stimulation therapy(CST) mild dementia cognitive function DEPRESSION quasiexperimental study
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Numerical and Experimental Study of Thermal Storage Energy in a Building with Various Pipeline Design under Floor—Case Study
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作者 Rafah H.Zaidan Najim A.Jasim 《Frontiers in Heat and Mass Transfer》 2025年第5期1595-1620,共26页
This paper presents a comprehensive experimental and numerical investigation of radiant floor heating(RFH)systems integrated with phase changematerial(PCM)-based thermal energy storage(TES).The study compares two unde... This paper presents a comprehensive experimental and numerical investigation of radiant floor heating(RFH)systems integrated with phase changematerial(PCM)-based thermal energy storage(TES).The study compares two underfloor pipe configurations:double serpentine and spiral.It also looks at how well a paraffin wax PCM system works with compact heat exchanger-type TES units during winter in Iraq.Key performance indicators including discharge temperature,heat transfer rate,liquid fraction evolution,and temperature uniformity were assessed through in situ experimental measurements and ANSYS fluent simulations.Results demonstrate that the spiral design provides slightly more uniform temperature distribution on the tile surface at an inlet water temperature of 55℃,with an average difference of approximately 0.5%,the serpentine layout exhibits higher slab temperature distribution by about 0.66%.Notably,the serpentine configuration shows superior thermal homogeneity and heat distribution,with a 15.05%increase in heat gain at a 55℃ inlet temperature compared to the spiral design.The performance gap between the two layouts narrows as the inlet temperature increases from 50℃ in 5℃ increments by approximately 4.1%,3.7%,and 1.7%,respectively.Higher inlet temperatures also improve PCM discharging and charging rates,improving energy storage utilization.The findings provide significant design guidelines for sustainable heating systems for cold climates. 展开更多
关键词 Radiant floor heating systems phase change materials(PCM) paraffin wax thermal energy storage experimental invistagation numerical thermal energy
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Causal relationships of inflammatory cytokines and serum metabolites with colorectal carcinoma: A Mendelian randomization study
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作者 FENG Sisi XIAO Xiaomin +2 位作者 ZHOU Manli HUANG Zixin ZHONG Baiyun 《中南大学学报(医学版)》 北大核心 2026年第1期118-128,共11页
Objective:The incidence and mortality of colorectal carcinoma(CRC)continue to rise globally,highlighting the need to identify modifiable risk factors for early detection and prevention.Previous studies have demonstrat... Objective:The incidence and mortality of colorectal carcinoma(CRC)continue to rise globally,highlighting the need to identify modifiable risk factors for early detection and prevention.Previous studies have demonstrated significant associations between CRC risk and various serum metabolites as well as inflammatory cytokines;however,due to limitations in study design and potential confounding factors,the causal relationships remain unclear.This study aims to investigate the causal relationships between inflammatory cytokines,serum metabolites,and CRC risk,providing a theoretical basis for the development of novel early diagnostic biomarkers and therapeutic targets.Methods:A two-sample Mendelian randomization(MR)design was applied using summary statistics from genome-wide association studies(GWAS).Instrumental variables(IVs)were derived from:1)metabolomics GWAS data of 1400 serum metabolites(n=8299);2)cytokine GWAS data of 91 inflammatory factors(n=14824);and 3)CRC risk data from the FinnGen consortium(6847 cases and 314193 controls).The primary analysis was conducted using the inverse-variance weighted(IVW)method,with sensitivity analyses performed using MR Egger regression and the weighted median method.Effect estimates including odds ratios(OR),95%confidence intervals(CI),and false discovery rates(FDR)were calculated.Results:MR analysis indicated that higher levels of axin-1(AXIN1)(OR=0.84195%CI 0.714 to 0.991)and Fms-related tyrosine kinase 3 ligand(Flt3L)(OR=0.916,95%CI 0.844 to 0.994)were associated with a reduced risk of CRC.In contrast,higher levels of Delta/Notchlike epidermal growth factor-related receptor(DNER)(OR=1.119,95%CI 1.009 to 1.241)and vascular endothelial growth factor A(VEGF-A)(OR=1.078,95%CI 1.011 to 1.150)were associated with an increased risk of CRC(all P<0.05).Metabolomics association analysis further identified 144 serum metabolites significantly correlated with these four key inflammatory cytokines(FDR<0.05),suggesting that they may regulate CRC risk through inflammatory pathways.Conclusion:Specific inflammatory cytokines and serum metabolites have causal relationships with the risk of CRC.These findings provide insights for further exploration of potential risk factors and the development of effective prevention strategies for CRC. 展开更多
关键词 inflammatory cytokines serum metabolites colorectal carcinoma Mendelian randomization genome-wide association study metabolomics analysis
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Real-time NMR experimental study of displacement-imbibition coupling in tight/shale oil reservoirs:Lithological variations,influencing factors,and key insights
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作者 Bin-Yu Wang Ren-Yi Cao +5 位作者 Xin-Yi Zheng Lin-Song Cheng Jiang-Peng Hu Zhi-Hao Jia Wen-Hao Duan Hassan Hassanzadeh 《Petroleum Science》 2025年第12期5142-5165,共24页
Displacement-imbibition coupling production is a pivotal technology for enhancing oil recovery(EOR)in waterflooded tight/shale oil reservoirs.However,the microscopic fluid transport mechanisms across different pore sc... Displacement-imbibition coupling production is a pivotal technology for enhancing oil recovery(EOR)in waterflooded tight/shale oil reservoirs.However,the microscopic fluid transport mechanisms across different pore scales remain inadequately understood.This study presents an innovative real-time nuclear magnetic resonance(NMR)experimental system integrated with MRI-based image processing to dynamically monitor oil-water distribution and quantify local oil saturation during injection-shut-in-production.This approach enables quantitative evaluation of pore utilization across different pore size ranges and reveals the impacts of various driving forces on oil displacement efficiency.The results show that displacement-imbibition coupling production employs multiple mechanisms to achieve balanced contributions from pores of all size scales.The displacement-imbibition oil production mainly consists of three stages:displacement-dominated injection,capillary-driven imbibition during shut-in,and displacement-imbibition coupling effects during production.Pressure oscillations significantly enhance matrix-fracture exchange by lowering pore-throat entry thresholds and redistributing pressure fields.Quantitative analysis shows that large pore dominate early displacement,while small pore contribute more during imbibition.Lithology and pore-throat connectivity critically influence displacement efficiency;vitric tuff outperforms argillaceous siltstone by up to 11.8%.Notably,greater fracture complexity increases the oil-water contact area,enhancing capillary imbibition,reducing reliance on displacement forces,and increasing the contribution of displacement-imbibition coupling effects to oil displacement efficiency by 15.35%.Artificially modifying the pressure field to induce pressure oscillations,effectively utilizing the high conductivity of fractures,and fully leveraging the displacement-imbibition coupling effects within matrix pores are crucial for achieving optimal EOR.Lastly,a new concept of nonlinear flow zoning is introduced to describe spatial variations in flow behavior under complex coupling conditions.These experimentally validated insights into matrix-fracture interactions provide theoretical support for designing improved waterflooding strategies and optimizing oil recovery in tight and shale reservoirs. 展开更多
关键词 Displacement-imbibition coupling mechanisms Matrix and fracture Lithologies Nuclear magnetic resonance(NMR)experiment Tight/shale oil reservoir Pore scale
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A Benchmark Study of Density Functional Theory(DFT)Methods for Mo-Catalyzed Carbonyl Oxidative Addition
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作者 Chen Zitong Wang Liwei +1 位作者 Shen Xiao Qi Xiaotian 《有机化学》 北大核心 2026年第2期507-514,共8页
In molybdenum chemistry,the oxidative addition of o-quinone or 1,2-dicarbonyl compounds to molybdenum has been widely used in Mo-catalyzed C—C bond construction.The carbonyl oxidative addition to Mo(0)or Mo(Ⅱ)is the... In molybdenum chemistry,the oxidative addition of o-quinone or 1,2-dicarbonyl compounds to molybdenum has been widely used in Mo-catalyzed C—C bond construction.The carbonyl oxidative addition to Mo(0)or Mo(Ⅱ)is the critical elementary reaction of molybdenum catalysis.However,the relevant density functional theory(DFT)studies are relatively scarce,especially regarding the rational selection of functionals.In this work,14 functionals were employed to investigate the Mo-catalyzed carbonyl oxidative addition step.A benchmark study was carried out to evaluate their performance in structure optimization and energy calculation.Analyses of mean absolute error(MAE)and mean squared error(MSE)indicated that the B3LYP-D3(BJ),TPSSh,and ωB97X-D functionals exhibited superior performance in structure optimization.Using the DLPNO-CCSD(T)functional as the reference,the M06,M06-L,and MN15-L functionals exhibited good performance for energy calculation based on the structures optimized using the B3LYP-D3(BJ)functional.In particular,MN15-L provided the best performance with the smallest MAE and MSE. 展开更多
关键词 molybdenum catalysis carbonyl oxidation addition density functional theory(DFT)calculation DFT benchmark study
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Root cause analysis from the perspectives of patients in primary care units:cases study of typical adverse drug events
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作者 Ping Gong Xing-Yang Chen +1 位作者 Qin Long Ting-Ting Zhou 《Frontiers of Nursing》 2026年第1期61-68,共8页
Objective:To identify the root causes of typical adverse drug events through the lens of patient experiences proposing novel strategies to mitigate preventable harm.Methods:A qualitative case study leveraging in-depth... Objective:To identify the root causes of typical adverse drug events through the lens of patient experiences proposing novel strategies to mitigate preventable harm.Methods:A qualitative case study leveraging in-depth interviews with patients and families,anchored by Interactive Patient Par ticipation Theory,to analyze 4 high-severity adverse drug events(ADE)cases.Cases were purposively sampled from 8 communities in China's National Adverse Event Monitor Center(2018-2023).Semi-structured interviews explored patient perspectives,with data analyzed via thematic coding and triangulation against clinical records.Results:Five interconnected themes emerged:(1)erosion of trust,(2)communication breakdowns,(3)information asymmetry,(4)environmental inadequacies,and(5)technological alienation.Notably,75% of participants had≤high school education,and 50% used≥7 medications daily,compounding ADE risks.Conclusions:We considered elements mentioned by theory,exploring trust,communication,information,and suppor t as the root causes.In addition,we added“adaptability to new technology”as an impor tant and necessary component.It is impor tant and necessary to analyze typical adverse drug events from the perspectives of patients. 展开更多
关键词 adverse drug events case study medication safety patients safety primary care units root cause analysis qualitative study THEORY
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