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The chemical environment and structural ordering in liquid Mg-Y-Zn system:An ab-initio molecular dynamics investigation of melt for the formation mechanism of LPSO structure
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作者 Tangpeng Ma Jin Wang +5 位作者 Kaiming Cheng Chengwei Zhan Jixue Zhou Jingyu Qin Guochen Zhao Xinfang Zhang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第2期815-824,共10页
In an effort to clarify the formation mechanism of LPSO structure in Mg-Y-Zn alloy,the chemical environment and structural ordering in liquid Mg-rich Mg-Y-Zn system are investigated with the aid of ab-initio molecular... In an effort to clarify the formation mechanism of LPSO structure in Mg-Y-Zn alloy,the chemical environment and structural ordering in liquid Mg-rich Mg-Y-Zn system are investigated with the aid of ab-initio molecular dynamics simulation.In liquid Mg-rich Mg-Y alloys,the strong Mg-Y interaction is determined,which promotes the formation of fivefold symmetric local structure.For Mg-Zn alloys,the weak Mg-Zn interaction results in the fivefold symmetry weakening in the liquid structure.Due to the coexistence of Y and Zn,the strong attractive interaction is introduced in liquid Mg-Y-Zn ternary alloy,and contributes to the clustering of Mg,Y,Zn launched from Zn.What is more,the distribution of local structures becomes closer to that in pure Mg compared with that in binary Mg-Y and Mg-Zn alloys.These results should relate to the origins of the Y/Zn segregation zone and close-packed stacking mode in LPSO structure,which provides a new insight into the formation mechanism of LPSO structure at atomic level. 展开更多
关键词 Mg-Y-Zn Chemical environment Structural ordering ab-initio molecular dynamics
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Comparative Study of the Reliability and Complexity of Symmetrical and Asymmetrical Cryptosystems for the Protection of Academic Data in the Democratic Republic of Congo
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作者 Mugaruka Buduge Gulain Jeremie Ndikumagenge +2 位作者 Buhendwa Nyenyezi Justin Bulonza Masumbuko Alexis Katho Seba Jacques 《Journal of Information Security》 2024年第3期299-307,共9页
In the digital age, the data exchanged within a company is a wealth of knowledge. The survival, growth and influence of a company in the short, medium and long term depend on it. Indeed, it is the lifeblood of any mod... In the digital age, the data exchanged within a company is a wealth of knowledge. The survival, growth and influence of a company in the short, medium and long term depend on it. Indeed, it is the lifeblood of any modern company. A companys operational and historical data contains strategic and operational knowledge of ever-increasing added value. The emergence of a new paradigm: big data. Today, the value of the data scattered throughout this mother of knowledge is calculated in billions of dollars, depending on its size, scope and area of intervention. With the rise of computer networks and distributed systems, the threats to these sensitive resources have steadily increased, jeopardizing the existence of the company itself by drying up production and losing the interest of customers and suppliers. These threats range from sabotage to bankruptcy. For several decades now, most companies have been using encryption algorithms to protect and secure their information systems against the threats and dangers posed by the inherent vulnerabilities of their infrastructure and the current economic climate. This vulnerability requires companies to make the right choice of algorithms to implement in their management systems. For this reason, the present work aims to carry out a comparative study of the reliability and effectiveness of symmetrical and asymmetrical cryptosystems, in order to identify one or more suitable for securing academic data in the DRC. The analysis of the robustness of commonly used symmetric and asymmetric cryptosystems will be the subject of simulations in this article. 展开更多
关键词 Comparative study CRYPTOsystemS Symmetric Encryption Asymmetric Encryption
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Violence study of healthcare workers and systems in the Caribbean:ViSHWaS-Caribbean study
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作者 Reshon Hadmon Daniella Myriam Pierre +12 位作者 Akshat Banga Jacques W Clerville Hans Mautong Precious Akinsanya Rajat Das Gupta Sama Soliman Tolupe M Hunjah Bamidele A Hunjah Hafeez Hamza Ruman Khurshid Qasba Faisal A Nawaz Salim Surani Rahul Kashyap 《World Journal of Methodology》 2024年第3期106-118,共13页
BACKGROUND Violence against healthcare workers(HCWs)in the Caribbean continues to prevail yet remains underreported.Our aim is to determine the cause,traits,and consequences of violence on HCWs in the Caribbean.AIM To... BACKGROUND Violence against healthcare workers(HCWs)in the Caribbean continues to prevail yet remains underreported.Our aim is to determine the cause,traits,and consequences of violence on HCWs in the Caribbean.AIM To determine the cause,traits,and consequences of violence on HCWs in the Caribbean.METHODS This research adopted an online cross-sectional survey approach,spanning over eight weeks(between June 6th and August 9th,2022).The survey was generated using Research Electronic Data Capture forms and followed a snowballing strategy to contact individuals using emails,social media,text messages,etc.Logistic regression analysis was performed to evaluate the variables that influence violence,including gender,age,years of experience,institution type,and night shift frequency.RESULTS The survey was completed by 225 HCWs.Females comprised 61%.Over 51%of respondents belonged to the 21 to 35 age group.Dominica(n=61),Haiti(n=50),and Grenada(n=31)had the most responses.Most HCWs(49%)worked for government academic institutions,followed by community hospitals(23%).Medical students(32%),followed by attending physicians(22%),and others(16%)comprised the most common cadre of respondents.About 39%of the participants reported experiencing violence themselves,and 18%reported violence against colleague(s).Verbal violence(48%),emotional abuse(24%),and physical misconduct(14%)were the most common types of violence.Nearly 63%of respondents identified patients or their relatives as the most frequent aggressors.Univariate logistic regression analyses demonstrated that female gender(OR=2.08;95%CI:1.16-3.76,P=0.014)and higher frequency of night shifts(OR=2.22;95%CI:1.08-4.58,P=0.030)were associated with significantly higher odds of experiencing violence.More than 50%of HCWs felt less motivated and had decreased job satisfaction post-violent conduct.CONCLUSION A large proportion of HCWS in the Caribbean are exposed to violence,yet the phenomenon remains underreported.As a result,HCWs’job satisfaction has diminished. 展开更多
关键词 ViSHWaS Healthcare workers VIOLENCE SURVEY Workplace violence Caribbean Cross-sectional study
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Recent progresses in the development of tubular segmented-in-series solid oxide fuel cells:Experimental and numerical study 被引量:2
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作者 Shuo Han Tao Wei +6 位作者 Sijia Wang Yanlong Zhu Xingtong Guo Liang He Xiongzhuang Li Qing Huang Daifen Chen 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第3期427-442,共16页
Solid oxide fuel cells(SOFCs)have attracted a great deal of interest because they have the highest efficiency without using any noble metal as catalysts among all the fuel cell technologies.However,traditional SOFCs s... Solid oxide fuel cells(SOFCs)have attracted a great deal of interest because they have the highest efficiency without using any noble metal as catalysts among all the fuel cell technologies.However,traditional SOFCs suffer from having a higher volume,current leakage,complex connections,and difficulty in gas sealing.To solve these problems,Rolls-Royce has fabricated a simple design by stacking cells in series on an insulating porous support,resulting in the tubular segmented-in-series solid oxide fuel cells(SIS-SOFCs),which achieved higher output voltage.This work systematically reviews recent advances in the structures,preparation methods,perform-ances,and stability of tubular SIS-SOFCs in experimental and numerical studies.Finally,the challenges and future development of tubular SIS-SOFCs are also discussed.The findings of this work can help guide the direction and inspire innovation of future development in this field. 展开更多
关键词 solid oxide fuel cell SEGMENTED-IN-SERIES TUBULAR experimental study numerical study
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The association of diet quality and physical activity with cardiovascular disease and mortality in 85,545 older Australians:A longitudinal study 被引量:1
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作者 Ding Ding Joe Van Buskirk +6 位作者 Stephanie Partridge Philip Clare Edward Giovannucci Adrian Bauman Nicole Freene Robyn Gallagher Binh Nguyen 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第6期841-850,共10页
Background:A quality diet and an active lifestyle are both important cornerstones of cardiovascular disease(CVD)prevention.However,despite their interlinked effects on metabolic health,the 2 behaviors are rarely consi... Background:A quality diet and an active lifestyle are both important cornerstones of cardiovascular disease(CVD)prevention.However,despite their interlinked effects on metabolic health,the 2 behaviors are rarely considered jointly,particularly within the context of CVD prevention.We examined the independent,interactive,and joint associations of diet and physical activity with CVD hospitalization,CVD mortality,and all-cause mortality.Methods:CVD-free Australian participants aged 4574 years(n=85,545)reported physical activity,diet,sociodemographic,and lifestyle characteristics at baseline(20062009)and follow-up(20122015),and data were linked to hospitalization and death registries(03/31/2019 for CVD hospitalization and all-cause mortality and 12/08/2017 for CVD mortality).Diet quality was categorized as low,medium,and high based on meeting dietary recommendations.Physical activity was operationalized as(a)total moderate-to-vigorous physical activity(MVPA)as per guidelines,and(b)the composition of MVPA as the ratio of vigorous-intensity physical activity(VPA)to total MVPA.We used a left-truncated cause-specific Cox proportional hazards model using time-varying covariates.Results:During a median of 10.7 years of follow-up,6576 participants were admitted to the hospital for CVD and 6581 died from all causes(876 from CVD during 9.3 years).A high-quality diet was associated with a 17%lower risk of all-cause mortality than a low-quality diet,and the highest MVPA category(compared with the lowest)was associated with a 44%and 48%lower risk of CVD and all-cause mortality,respectively.Multiplicative interactions between diet and physical activity were non-significant.For all outcomes,the lowest risk combinations involved a high-quality diet and the highest MVPA categories.Accounting for total MVPA,some VPA was associated with further risk reduction of CVD hospitalization and all-cause mortality.Conclusion:For CVD prevention and longevity,one should adhere to both a healthy diet and an active lifestyle and incorporate some VPA when possible. 展开更多
关键词 DIET Physical activity Cardiovascular disease MORTALITY Cohort studies
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Effect of distribution shape on the melting transition, local ordering,and dynamics in a model size-polydisperse two-dimensional fluid
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作者 Jackson Pame Lenin SShagolsem 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期419-428,共10页
We study the effect of particle size polydispersity(δ) on the melting transition(T*), local ordering, solid–liquid coexistence phase and dynamics of two-dimensional Lennard–Jones fluids up to moderate polydispersit... We study the effect of particle size polydispersity(δ) on the melting transition(T*), local ordering, solid–liquid coexistence phase and dynamics of two-dimensional Lennard–Jones fluids up to moderate polydispersity by means of computer simulations. The particle sizes are drawn at random from the Gaussian(G) and uniform(U) distribution functions.For these systems, we further consider two different kinds of particles, viz., particles having the same mass irrespective of size, and in the other case the mass of the particle scales with its size. It is observed that with increasing polydispersity,the value of T*initially increases due to improved packing efficiency(φ) followed by a decrease and terminates at δ ≈8%(U-system) and 14%(G-system) with no significant difference for both mass types. The interesting observation is that the particular value at which φ drops suddenly coincides with the peak of the heat capacity(CP) curve, indicating a transition. The quantification of local particle ordering through the hexatic order parameter(Q_6), Voronoi construction and pair correlation function reveals that the ordering decreases with increasing δ and T. Furthermore, the solid–liquid coexistence region for the G-system is shown to be comparatively wider in the T –δ plane phase diagram than that for the U system. Finally, the study of dynamics reveals that polydisperse systems relax faster compared to monodisperse systems;however, no significant qualitative differences, depending on the distribution type and mass polydispersity, are observed. 展开更多
关键词 POLYDISPERSITY orderING phase diagram DYNAMICS
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Pedestrian lane formation with following–overtaking model and measurement of system order
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作者 李碧璐 李政 +1 位作者 周睿 申世飞 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期247-263,共17页
Pedestrian self-organizing movement plays a significant role in evacuation studies and architectural design.Lane formation,a typical self-organizing phenomenon,helps pedestrian system to become more orderly,the majori... Pedestrian self-organizing movement plays a significant role in evacuation studies and architectural design.Lane formation,a typical self-organizing phenomenon,helps pedestrian system to become more orderly,the majority of following behavior model and overtaking behavior model are imprecise and unrealistic compared with pedestrian movement in the real world.In this study,a pedestrian dynamic model considering detailed modelling of the following behavior and overtaking behavior is constructed,and a method of measuring the lane formation and pedestrian system order based on information entropy is proposed.Simulation and analysis demonstrate that the following and avoidance behaviors are important factors of lane formation.A high tendency of following results in good lane formation.Both non-selective following behavior and aggressive overtaking behavior cause the system order to decrease.The most orderly following strategy for a pedestrian is to overtake the former pedestrian whose speed is lower than approximately 70%of his own.The influence of the obstacle layout on pedestrian lane and egress efficiency is also studied with this model.The presence of a small obstacle does not obstruct the walking of pedestrians;in contrast,it may help to improve the egress efficiency by guiding the pedestrian flow and mitigating the reduction of pedestrian system orderliness. 展开更多
关键词 pedestrian movement lane formation information entropy order degree
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The growth ofβphase in Mg-Gd-Y-Ni alloy by experimental and first-principles study
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作者 Yiqiang Hao Lei Zhou +2 位作者 Zhiqing Chen Zhixian Zhao Bin Chen 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第2期506-515,共10页
The paper reports on the atomic investigation aboutβphase in Mg_(96)Gd_(2)Y_(1)Ni_(1) alloy by using the first-principles study and the high-angle annular dark-field scanning transmission electron microscope(HAADF-ST... The paper reports on the atomic investigation aboutβphase in Mg_(96)Gd_(2)Y_(1)Ni_(1) alloy by using the first-principles study and the high-angle annular dark-field scanning transmission electron microscope(HAADF-STEM)corrected by atomic Cs.By using HAADF-STEM,the rectangularβphases were observed in the underage and peak aging stages in Mg_(96)Gd_(2)Y_(1)Ni_(1) alloy.Theβphase could be precipitated from the previously precipitatedβphase,and theβphase grew in steps when it was precipitated.A special transition structure of three atomic layer thicknesses was first observed at the edge of theβphase and the structure of this interface is probably as theβ/Mg_(1) interface for the analysis of thermodynamic characterization and electronic characterization.Theβ'phase and theβ_(H) structure were precipitated only at the edge of the length directions of theβphase.Theβ'phase continues to grow into aβphase directly without the formation ofβ_(1) phase,resulting in an increase in the length of theβphase,which is discovered for the first time. 展开更多
关键词 HAADF-STEM First-principles study Mg-Gd-Y-Ni alloy βphase GROWTH INTERFACE
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The Disintegration of a Floating Ferrofluid Layer into an Ordered Drop System in a Vertical Magnetic Field
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作者 Christina Khokhryakova Konstantin Kostarev Irina Mizeva 《Fluid Dynamics & Materials Processing》 EI 2024年第10期2205-2218,共14页
Magnetic fluids,also known as ferrofluids,are versatile functional materials with a wide range of applications.These applications span from industrial uses such as vacuum seals,actuators,and acoustic devices to medica... Magnetic fluids,also known as ferrofluids,are versatile functional materials with a wide range of applications.These applications span from industrial uses such as vacuum seals,actuators,and acoustic devices to medical uses,including serving as contrast agents for magnetic resonance imaging(MRI),delivering medications to specific locations within the body,and magnetic hyperthermia for cancer treatment.The use of a non-wettable immiscible liquid substrate to support a layer of magnetic fluid opens up new possibilities for studying various fluid flows and related instabilities in multi-phase systems with both a free surface and an interface.The presence of two deformable boundaries within a ferrofluid layer significantly reduces the critical magnetic field strength required to transform the layer into an organized system of drops or polygonal figures evolving according to the intensity,frequency and direction of the considered magnetic field.This paper experimentally investigates this problem by assuming a uniform magnetic field perpendicular to the surface.This specific subject has not been previously explored experimentally.The critical magnetic field intensity required to destabilize the ferrofluid layer is determined based on the layer’s thickness and the fluid’s initial magnetic susceptibility.It is demonstrated that the critical magnetic field strength needed to disrupt the initially continuous ferrofluid layer increases with the layer’s thickness.Conversely,an increase in the ferrofluid’s magnetic susceptibility results in a decrease in the critical magnetic field strength.The emerging droplet structures are analyzed in terms of the number of drops,their size,and the periodicity of their arrangement.The number of droplets formed depends on the initial thickness of the layer,the presence or absence of a stable rupture in the upper layer,and the rate at which the magnetic field strength is increased to the critical value.A characteristic viscous time is proposed to evaluate the decomposition of the ferrofluid layer,which depends on the duration of the magnetic field’s application.The experimental data on the instability of a ferrofluid layer on a liquid substrate are compared with the theoretical results from the study of“magnetic fluid sandwich structures”conducted by Rannacher and Engel.This comparison highlights the similarities and differences between experimental observations and theoretical predictions,providing a deeper understanding of the behavior of ferrofluid layers under the influence of magnetic fields. 展开更多
关键词 FERRofLUID liquid substrate normal field instability ordered droplet structure
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Advanced 3D ordered electrodes for PEMFC applications: From structural features and fabrication methods to the controllable design of catalyst layers
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作者 Kaili Wang Tingting Zhou +4 位作者 Zhen Cao Zhimin Yuan Hongyan He Maohong Fan Zaiyong Jiang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第9期1336-1365,共30页
The catalyst layers(CLs) electrode is the key component of the membrane electrode assembly(MEA) in proton exchange membrane fuel cells(PEMFCs). Conventional electrodes for PEMFCs are composed of carbon-supported, iono... The catalyst layers(CLs) electrode is the key component of the membrane electrode assembly(MEA) in proton exchange membrane fuel cells(PEMFCs). Conventional electrodes for PEMFCs are composed of carbon-supported, ionomer, and Pt nanoparticles, all immersed together and sprayed with a micron-level thickness of CLs. They have a performance trade-off where increasing the Pt loading leads to higher performance of abundant triple-phase boundary areas but increases the electrode cost. Major challenges must be overcome before realizing its wide commercialization. Literature research revealed that it is impossible to achieve performance and durability targets with only high-performance catalysts, so the controllable design of CLs architecture in MEAs for PEMFCs must now be the top priority to meet industry goals. From this perspective, a 3D ordered electrode circumvents this issue with a support-free architecture and ultrathin thickness while reducing noble metal Pt loadings. Herein, we discuss the motivation in-depth and summarize the necessary CLs structural features for designing ultralow Pt loading electrodes. Critical issues that remain in progress for 3D ordered CLs must be studied and characterized. Furthermore, approaches for 3D ordered CLs architecture electrode development, involving material design, structure optimization, preparation technology, and characterization techniques, are summarized and are expected to be next-generation CLs for PEMFCs. Finally, the review concludes with perspectives on possible research directions of CL architecture to address the significant challenges in the future. 展开更多
关键词 PEMFC 3D ordered electrode Structural features Preparation technology Ultralow Pt loading
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Theoretical and Experimental Study on the Performance of Hermetic Diaphragm Squeeze Film Dampers for Gas-Lubricated Bearings
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作者 Jianwei Wang Haoxi Zhang +3 位作者 Shaocun Han Hang Li Peng Wang Kai Feng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期151-169,共19页
Low damping characteristics have always been a key sticking points in the development of gas bearings.The application of squeeze film dampers can significantly improve the damping performance of gas lubricated bearing... Low damping characteristics have always been a key sticking points in the development of gas bearings.The application of squeeze film dampers can significantly improve the damping performance of gas lubricated bearings.This paper proposed a novel hermetic diaphragm squeeze film damper(HDSFD)for oil-free turbomachinery supported by gas lubricated bearings.Several types of HDSFDs with symmetrical structure were proposed for good damping performance.By considering the compressibility of the damper fluid,based on hydraulic fluid mechanics theory,a dynamic model of HDSFDs under medium is proposed,which successfully reflects the frequency dependence of force coefficients.Based on the dynamic model,the effects of damper fluid viscosity,bulk modulus of damper fluid,thickness of damper fluid film and plunger thickness on the dynamic stiffness and damping of HDSFDs were analyzed.An experimental test rig was assembled and series of experimental studies on HDSFDs were conducted.The damper fluid transverse flow is added to the existing HDSFD concept,which aims to make the dynamic force coefficients independent of frequency.Although the force coefficient is still frequency dependent,the damping coefficient at high frequency excitation with damper fluid supply twice as that without damper fluid supply.The results serve as a benchmark for the calibration of analytical tools under development. 展开更多
关键词 Hermetic diaphragm squeeze film damper COMPRESSIBILITY Dynamic model Experimental studies
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The relationship between compartment models and their stochastic counterparts:A comparative study with examples of the COVID-19 epidemic modeling
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作者 Ziyu Zhao Yi Zhou +6 位作者 Jinxing Guan Yan Yan Jing Zhao Zhihang Peng Feng Chen Yang Zhao Fang Shao 《Journal of Biomedical Research》 CAS CSCD 2024年第2期175-188,I0016-I0018,共17页
Deterministic compartment models(CMs)and stochastic models,including stochastic CMs and agent-based models,are widely utilized in epidemic modeling.However,the relationship between CMs and their corresponding stochast... Deterministic compartment models(CMs)and stochastic models,including stochastic CMs and agent-based models,are widely utilized in epidemic modeling.However,the relationship between CMs and their corresponding stochastic models is not well understood.The present study aimed to address this gap by conducting a comparative study using the susceptible,exposed,infectious,and recovered(SEIR)model and its extended CMs from the coronavirus disease 2019 modeling literature.We demonstrated the equivalence of the numerical solution of CMs using the Euler scheme and their stochastic counterparts through theoretical analysis and simulations.Based on this equivalence,we proposed an efficient model calibration method that could replicate the exact solution of CMs in the corresponding stochastic models through parameter adjustment.The advancement in calibration techniques enhanced the accuracy of stochastic modeling in capturing the dynamics of epidemics.However,it should be noted that discrete-time stochastic models cannot perfectly reproduce the exact solution of continuous-time CMs.Additionally,we proposed a new stochastic compartment and agent mixed model as an alternative to agent-based models for large-scale population simulations with a limited number of agents.This model offered a balance between computational efficiency and accuracy.The results of this research contributed to the comparison and unification of deterministic CMs and stochastic models in epidemic modeling.Furthermore,the results had implications for the development of hybrid models that integrated the strengths of both frameworks.Overall,the present study has provided valuable epidemic modeling techniques and their practical applications for understanding and controlling the spread of infectious diseases. 展开更多
关键词 compartment models agent-based models compartment-agent mixed models comparative study COVID-19
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An Analysis of Specific Categories of Birth Defects and Developmental Disabilities for Children of Participants of the Air Force Health Study
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作者 George J. Knafl 《Open Journal of Epidemiology》 2024年第2期312-330,共19页
Background: The Air Force Health Study collected reproductive outcomes for live-born children of male Air Force veterans of the Vietnam War. Methods: Dioxin values for participants were obtained from blood samples. An... Background: The Air Force Health Study collected reproductive outcomes for live-born children of male Air Force veterans of the Vietnam War. Methods: Dioxin values for participants were obtained from blood samples. Analyses were conducted of occurrence of 16 specific categories of birth defects and developmental disabilities. Children were categorized as conceived before and after the start of participants’ Vietnam War service. Children conceived before the start of Vietnam War service were treated as being conceived when their fathers had unquantifiable dioxin values. Children conceived after the start of Vietnam War service for participants with missing dioxin values were excluded from primary analyses, but were used to assess the impact of their exclusion on conclusions. Correlation between values for specific categories for multiple children fathered by the same participant was accounted for. The dose-response relationship was treated as a step function increasing for dioxin values larger than adaptively identified individual thresholds changing with the specific category. Results: For 15 of 16 specific categories, the probability of occurrence increased substantially for a sufficiently high dioxin level above identified thresholds. Exclusion of children due to missing dioxin likely did not affect these results. Conclusions: Results supported the conclusion of substantial adverse effects on a wide variety of specific categories of birth defects and developmental disabilities due to sufficiently high exposures to dioxin, a toxic contaminant of Agent Orange used for herbicide spraying in the Vietnam War. Results may hold more generally, but might also have been affected by a variety of limitations. 展开更多
关键词 Agent Orange Air Force Health study Birth Defects Developmental Disabilities DIOXIN Dose-Response Relationship Vietnam War
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Development and Validation of an Automatic Ultrawide-Field Fundus Imaging Enhancement System for Facilitating Clinical Diagnosis:A Cross-Sectional Multicenter Study
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作者 Qiaoling Wei Zhuoyao Gu +19 位作者 Weimin Tan Hongyu Kong Hao Fu Qin Jiang Wenjuan Zhuang Shaochi Zhang Lixia Feng Yong Liu Suyan Li Bing Qin Peirong Lu Jiangyue Zhao Zhigang Li Songtao Yuan Hong Yan Shujie Zhang Xiangjia Zhu Jiaxu Hong Chen Zhao Bo Yan 《Engineering》 SCIE EI CAS CSCD 2024年第10期179-188,共10页
In ophthalmology,the quality of fundus images is critical for accurate diagnosis,both in clinical practice and in artificial intelligence(AI)-assisted diagnostics.Despite the broad view provided by ultrawide-field(UWF... In ophthalmology,the quality of fundus images is critical for accurate diagnosis,both in clinical practice and in artificial intelligence(AI)-assisted diagnostics.Despite the broad view provided by ultrawide-field(UWF)imaging,pseudocolor images may conceal critical lesions necessary for precise diagnosis.To address this,we introduce UWF-Net,a sophisticated image enhancement algorithm that takes disease characteristics into consideration.Using the Fudan University ultra-wide-field image(FDUWI)dataset,which includes 11294 Optos pseudocolor and 2415 Zeiss true-color UWF images,each of which is rigorously annotated,UWF-Net combines global style modeling with feature-level lesion enhancement.Pathological consistency loss is also applied to maintain fundus feature integrity,significantly improving image quality.Quantitative and qualitative evaluations demonstrated that UWF-Net outperforms existing methods such as contrast limited adaptive histogram equalization(CLAHE)and structure and illumination constrained generative adversarial network(StillGAN),delivering superior retinal image quality,higher quality scores,and preserved feature details after enhancement.In disease classification tasks,images enhanced by UWF-Net showed notable improvements when processed with existing classification systems over those enhanced by StillGAN,demonstrating a 4.62%increase in sensitivity(SEN)and a 3.97%increase in accuracy(ACC).In a multicenter clinical setting,UWF-Net-enhanced images were preferred by ophthalmologic technicians and doctors,and yielded a significant reduction in diagnostic time((13.17±8.40)s for UWF-Net enhanced images vs(19.54±12.40)s for original images)and an increase in diagnostic accuracy(87.71%for UWF-Net enhanced images vs 80.40%for original images).Our research verifies that UWF-Net markedly improves the quality of UWF imaging,facilitating better clinical outcomes and more reliable AI-assisted disease classification.The clinical integration of UWF-Net holds great promise for enhancing diagnostic processes and patient care in ophthalmology. 展开更多
关键词 Ultrawide-field imaging Fundus photography Image enhancement algorithm Artificial intelligence Multicenter study Artificial intelligence-assisted diagnostics Diagnostic accuracy
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Physico-Chemical and Microbiological Study of Fresh Pineapple(Baronne de Guinée)Grown in the Sub-prefectures of:Maferinyah and Friguiagbé(Forécariah and Kindia Prefectures),Republic of Guinea
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作者 Sâa Gérard Tolno Haicha Cissé +3 位作者 Amadou Sylla Mamadou Madaniou Sow Adama Moussa Sakho Lounceny Traore 《Journal of Environmental Science and Engineering(A)》 CAS 2024年第6期211-217,共7页
Pineapple fruit in the Republic of Guinea is currently less competitive in the West African sub-region due to the nutritional quality of the product.Thus,it is normal to review certain parameters such as:sensory,physi... Pineapple fruit in the Republic of Guinea is currently less competitive in the West African sub-region due to the nutritional quality of the product.Thus,it is normal to review certain parameters such as:sensory,physico-chemical in order to improve this classification.To do this,instead of buying samples on the market,the aim is to analyze fresh samples harvested in the production fields and send them to the laboratory for analysis of certain physico-chemical and microbiological parameters.Analytical results showed that the Brix content in fields I and II at Maferinyah(Forécariah)was higher(14.35 and 16.5)than that found in fields I and II at Friguiagbé(Kindia)(14.2 and 12.4),The pH of fruit from both localities varies between 3.48 and 3.56,with the highest acidity value found in Field I at Friguiagbé(Kindia)2.16 and the lowest value in Field II at Maferinyah(Forécariah)0.46.Moisture contents for both localities ranged from 82.56 to 89.5,with the highest value found at Field I in Maferinyah(Forécariah)89.5.Dry extract and ash in both localities would be in the range 10.54 to 17.45;0.33 to 1.43 respectively.The highest values for dry extract and ash were found in Fields I and II Friguiagbé(Kindia)17.45 and 1.43.The samples analyzed contained certain trace elements such as magnesium,sodium,iron and phosphorus.Microbiological analyses showed the presence of Escherichia coli(E.coli),yeast-molds,Staphylococcus aureus and the absence of salmonella. 展开更多
关键词 Fresh pineapple cultivated physicochemical study microbiology
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Study on the impact of comprehensive geriatric assessment on anxiety and depression in chronic obstructive pulmonary disease patients
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作者 Xian-Rong Shi Wen-Li Wu +4 位作者 Chun-Yan Li Jiao Ao Hai-Xia Xiong Jing Guo Yan Fang 《World Journal of Clinical Cases》 SCIE 2024年第20期4057-4064,共8页
BACKGROUND Psychological factors such as anxiety and depression will not only aggravate the symptoms of chronic obstructive pulmonary disease(COPD)patients and reduce the quality of life of patients,but also affect th... BACKGROUND Psychological factors such as anxiety and depression will not only aggravate the symptoms of chronic obstructive pulmonary disease(COPD)patients and reduce the quality of life of patients,but also affect the treatment effect and long-term prognosis.Therefore,it is of great significance to explore the clinical application of senile comprehensive assessment in the treatment of COPD and its influence on psychological factors such as anxiety and depression.AIM To explore the clinical application of comprehensive geriatric assessment in COPD care and its impact on anxiety and depression in elderly patents.METHODS In this retrospective study,60 patients with COPD who were hospitalized in our hospital from 2019 to 2020 were randomly divided into two groups with 30 patients in each group.The control group was given routine nursing,and the observation group was given comprehensive assessment.Clinical symptoms,quality of life[COPD assessment test(CAT)score],anxiety and depression Hamilton Anxiety Rating Scale(HAMA)and Hamilton Depression Rating Scale(HAMD)were compared between the two groups.RESULTS CAT scores in the observation group decreased from an average of 24.5 points at admission to an average of 18.3 points at discharge,and in the control group from an average of 24.7 points at admission to an average of 18.3 points at discharge.The average score was 22.1(P<0.05).In the observation group,HAMA scores decreased from 14.2 points at admission to 8.6 points at discharge,and HAMD scores decreased from 13.8 points at admission to 7.4 points at discharge.The mean HAMD scores in the control group decreased from an average of 14.5 at admission to an average of 12.3 at discharge,and from an average of 14.1 at admission to an average of 11.8 at discharge.CONCLUSION The application of comprehensive geriatric assessment in COPD care has a significant effect on improving patients'clinical symptoms and quality of life,and can effectively reduce patients'anxiety and depression. 展开更多
关键词 Chronic obstructive pulmonary disease Comprehensive geriatric assessment ANXIETY DEPRESSION Retrospective study Hamilton Anxiety Rating Scale
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Sex differences in the association between the muscle quality index and the incidence of depression: A cross-sectional study
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作者 Gui-Ping Huang Li-Ping Mai +2 位作者 Zhi-Jie Zheng Xi-Pei Wang Guo-Dong He 《World Journal of Psychiatry》 SCIE 2024年第9期1335-1345,共11页
BACKGROUND Depression presents significant challenges to mental health care.Although phy-sical activity is highly beneficial to mental and physical health,relatively few stu-dies have conducted on the relationship bet... BACKGROUND Depression presents significant challenges to mental health care.Although phy-sical activity is highly beneficial to mental and physical health,relatively few stu-dies have conducted on the relationship between them.AIM To investigate the association between muscle quality index(MQI)and incidence of depression.METHODS The data used in this cross-sectional study were obtained from the 2011-2014 National Health and Nutritional Examination Survey,which included informa-tion on MQI,depression,and confounding factors.Multivariable logistic regre-ssion models were employed,while taking into account the complex multi-stage sampling design.A restricted cubic spline model was utilized to investigate the non-linear relationship between the MQI and depression.Additionally,subgroup analyses were performed to identify influential factors.RESULTS The prevalence of depression in this population was 8.44%.With the adjusted model,the MQI was associated with depression in females(odds ratio=0.68,95%confidence interval:0.49-0.95)but not in males(odds ratio=1.08,95%confidence interval:0.77-1.52).Restricted cubic spline adjustment of all covariates showed a significant negative non-linear relationship between depression and the MQI in females.The observed trend indicated an 80%decrease in the risk of depression for each unit increase in MQI,until a value of 2.2.Subsequently,when the MQI exceeded 2.2,the prevalence of depression increased by 20%for every unit increase in the MQI.Subgroup analyses further confirmed that the MQI was negatively associated with de-pression.CONCLUSION The MQI was inversely correlated with depression in females but not males,suggesting that females with a higher MQI might decrease the risk of depression. 展开更多
关键词 Sex differences Muscle quality index DEPRESSION National Health and Nutrition Examination Survey Population-based study
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On the Local Convergence and Dynamics of New Iterative Method with Sixth Order Convergence
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作者 Lyu Borui Chu Xue Wang Haijun 《数学理论与应用》 2024年第3期50-66,共17页
In this paper,we construct a new sixth order iterative method for solving nonlinear equations.The local convergence and order of convergence of the new iterative method is demonstrated.In order to check the validity o... In this paper,we construct a new sixth order iterative method for solving nonlinear equations.The local convergence and order of convergence of the new iterative method is demonstrated.In order to check the validity of the new iterative method,we employ several chemical engineering applications and academic test problems.Numerical results show the good numerical performance of the new iterative method.Moreover,the dynamical study of the new method also supports the theoretical results. 展开更多
关键词 Nonlinear equation Sixth order method Local convergence Basin of attraction
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Lack of a causal relationship between tea intake and sleep disorders: a two-sample Mendelian randomization study
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作者 Hui Cheng Si-Min Wang +3 位作者 Ping-Wen Liu Wei-Chang Huang Jia Yuan Da-Yuan Zhong 《Medical Data Mining》 2024年第3期26-32,共7页
Background:The relationship between tea intake(TI)and sleep disorders(SDs)has been a topic of interest for some time,but there remains a lack of data showing a causal relationship.We aimed to use a two-sample Mendelia... Background:The relationship between tea intake(TI)and sleep disorders(SDs)has been a topic of interest for some time,but there remains a lack of data showing a causal relationship.We aimed to use a two-sample Mendelian randomization study to determine whether there is a causal link between TI and SDs.Methods:We collected data regarding TI,with a focus on green tea intake(GTI),herbal tea intake(HTI),and rooibos tea intake(RTI);and data regarding SDs and insomnia from genome-wide association studies.We analyzed these data using an inverse variance-weighted two-sample Mendelian randomization study,by means of the TwoSampleMR package in R4.2.3 software.Results:We found no genetic causal relationships of TI,GTI,HTI,or RTI with insomnia.The odds ratios(ORs)for these relationships were as follows:TI:OR=0.61,95%confidence interval(CI):0.29–1.28;GTI:OR=1.04,95%CI:0.95–1.14;HTI:OR=0.98,95%CI:0.82–1.17;and RTI:OR=1.04,95%CI:0.99–1.09.In addition,there were no genetic causal relationships of TI,GTI,HTI,or RTI with SDs.The OR values for these relationships were as follows:TI:OR=0.6,95%CI:0.34–1.06;GTI:OR=1,95%CI:0.93–1.07;HTI:OR=0.89,95%CI:0.66–1.2;and RTI:OR=1.02,95%CI:0.98–1.06.Conclusion:We found no causal relationships of TI with SDs or insomnia,irrespective of the type of tea consumed.However,additional Mendelian randomization studies are required to further explore the relationships of the timing and quantity of tea consumption with SDs and insomnia. 展开更多
关键词 tea intake sleep disorder INSOMNIA genome-wide association study Mendelian randomization study
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Cohort study on the treatment of BRAF V600E mutant metastatic colorectal cancer with integrated Chinese and western medicine
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作者 Jiang-Yu Bian Yu-Fang Feng +1 位作者 Wen-Ting He Tong Zhang 《World Journal of Clinical Oncology》 2025年第1期25-33,共9页
BACKGROUND Patients with BRAF V600E mutant metastatic colorectal cancer(mCRC)have a low incidence rate,poor biological activity,suboptimal response to conventional treatments,and a poor prognosis.In the previous cohor... BACKGROUND Patients with BRAF V600E mutant metastatic colorectal cancer(mCRC)have a low incidence rate,poor biological activity,suboptimal response to conventional treatments,and a poor prognosis.In the previous cohort study on mCRC conducted by our team,it was observed that integrated Chinese and Western medicine treatment could significantly prolong the overall survival(OS)of patients with colorectal cancer.Therefore,we further explored the survival benefits in the population with BRAF V600E mutant mCRC.AIM To evaluate the efficacy of integrated Chinese and Western medicine in the treatment of BRAF V600E mutant metastatic colorectal cancer.METHODS A cohort study was conducted on patients with BRAF V600E mutant metastatic colorectal cancer admitted to Xiyuan Hospital of China Academy of Chinese Medical Sciences and Traditional Chinese Medicine Hospital of Xinjiang Uygur Autonomous Region from January 2016 to December 2022.The patients were divided into two cohorts.RESULTS A total of 34 cases were included,with 23 in Chinese-Western medicine cohort(cohort A)and 11 in Western medicine cohort(cohort B).The median overall survival was 19.9 months in cohort A and 14.2 months in cohort B,with a statistically significant difference(P=0.038,hazard ratio=0.46).The 1-3-year survival rates were 95.65%(22/23),39.13%(9/23),and 26.09%(6/23)in cohort A,and 63.64%(7/11),18.18%(2/11),and 9.09%(1/11)in cohort B,respectively.Subgroup analysis showed statistically significant differences in median OS between the two cohorts in the right colon,liver metastasis,chemotherapy,and first-line treatment subgroups(P<0.05).CONCLUSION Integrated Chinese and Western medicine can prolong the survival and reduce the risk of death in patients with BRAF V600E mutant metastatic colorectal cancer,with more pronounced benefits observed in patients with right colon involvement,liver metastasis,combined chemotherapy,and first-line treatment. 展开更多
关键词 Metastatic colorectal cancer BRAF V600E mutation Integrated Chinese and Western medicine Cohort study
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