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Regeneration of the heart:f rom molecular mechanisms to clinical therapeutics 被引量:1
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作者 Qian-Yun Guo Jia-Qi Yang +1 位作者 Xun-Xun Feng Yu-Jie Zhou 《Military Medical Research》 SCIE CAS CSCD 2024年第1期80-97,共18页
Heart injury such as myocardial infarction leads to cardiomyocyte loss,fibrotic tissue deposition,and scar formation.These changes reduce cardiac contractility,resulting in heart failure,which causes a huge public hea... Heart injury such as myocardial infarction leads to cardiomyocyte loss,fibrotic tissue deposition,and scar formation.These changes reduce cardiac contractility,resulting in heart failure,which causes a huge public health burden.Military personnel,compared with civilians,is exposed to more stress,a risk factor for heart diseases,making cardiovascular health management and treatment innovation an important topic for military medicine.So far,medical intervention can slow down cardiovascular disease progression,but not yet induce heart regeneration.In the past decades,studies have focused on mechanisms underlying the regenerative capability of the heart and applicable approaches to reverse heart injury.Insights have emerged from studies in animal models and early clinical trials.Clinical interventions show the potential to reduce scar formation and enhance cardiomyocyte proliferation that counteracts the pathogenesis of heart disease.In this review,we discuss the signaling events controlling the regeneration of heart tissue and summarize current therapeutic approaches to promote heart regeneration after injury. 展开更多
关键词 Heart regeneration Cardiac disease THERAPEUTICS Signaling mechanisms
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Drug resistance mechanisms in cancers:Execution of prosurvival strategies 被引量:1
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作者 Pavan Kumar Dhanyamraju 《Journal of Biomedical Research》 CAS CSCD 2024年第2期95-121,共27页
One of the quintessential challenges in cancer treatment is drug resistance.Several mechanisms of drug resistance have been described to date,and new modes of drug resistance continue to be discovered.The phenomenon o... One of the quintessential challenges in cancer treatment is drug resistance.Several mechanisms of drug resistance have been described to date,and new modes of drug resistance continue to be discovered.The phenomenon of cancer drug resistance is now widespread,with approximately 90% of cancer-related deaths associated with drug resistance.Despite significant advances in the drug discovery process,the emergence of innate and acquired mechanisms of drug resistance has impeded the progress in cancer therapy.Therefore,understanding the mechanisms of drug resistance and the various pathways involved is integral to treatment modalities.In the present review,I discuss the different mechanisms of drug resistance in cancer cells,including DNA damage repair,epithelial to mesenchymal transition,inhibition of cell death,alteration of drug targets,inactivation of drugs,deregulation of cellular energetics,immune evasion,tumor-promoting inflammation,genome instability,and other contributing epigenetic factors.Furthermore,I highlight available treatment options and conclude with future directions. 展开更多
关键词 cancer drug resistance mechanisms MICRORNAS treatment strategies
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Overview of the immunological mechanisms in hepatitis B virus reactivation:Implications for disease progression and management strategies 被引量:1
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作者 Hui Ma Qing-Zhu Yan +2 位作者 Jing-Ru Ma Dong-Fu Li Jun-Ling Yang 《World Journal of Gastroenterology》 SCIE CAS 2024年第10期1295-1312,共18页
Hepatitis B virus(HBV)reactivation is a clinically significant challenge in disease management.This review explores the immunological mechanisms underlying HBV reactivation,emphasizing disease progression and manageme... Hepatitis B virus(HBV)reactivation is a clinically significant challenge in disease management.This review explores the immunological mechanisms underlying HBV reactivation,emphasizing disease progression and management.It delves into host immune responses and reactivation’s delicate balance,spanning innate and adaptive immunity.Viral factors’disruption of this balance,as are interac-tions between viral antigens,immune cells,cytokine networks,and immune checkpoint pathways,are examined.Notably,the roles of T cells,natural killer cells,and antigen-presenting cells are discussed,highlighting their influence on disease progression.HBV reactivation’s impact on disease severity,hepatic flares,liver fibrosis progression,and hepatocellular carcinoma is detailed.Management strategies,including anti-viral and immunomodulatory approaches,are critically analyzed.The role of prophylactic anti-viral therapy during immunosuppressive treatments is explored alongside novel immunotherapeutic interventions to restore immune control and prevent reactivation.In conclusion,this compre-hensive review furnishes a holistic view of the immunological mechanisms that propel HBV reactivation.With a dedicated focus on understanding its implic-ations for disease progression and the prospects of efficient management stra-tegies,this article contributes significantly to the knowledge base.The more profound insights into the intricate interactions between viral elements and the immune system will inform evidence-based approaches,ultimately enhancing disease management and elevating patient outcomes.The dynamic landscape of management strategies is critically scrutinized,spanning anti-viral and immunomodulatory approaches.The role of prophylactic anti-viral therapy in preventing reactivation during immunosuppressive treatments and the potential of innovative immunotherapeutic interventions to restore immune control and proactively deter reactivation. 展开更多
关键词 Hepatitis B virus reactivation Immunological mechanisms Disease progression Management strategies Immune response
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Role of methoxy and C_(α)-based substituents in electrochemical oxidation mechanisms and bond cleavage selectivity of β-O-4 lignin model compounds 被引量:1
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作者 Yang Zhou Qiang Zeng +3 位作者 Hongyan He Kejia Wu Fuqiao Liu Xuehui Li 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期114-125,共12页
In order to better understand the specific substituent effects on the electrochemical oxidation process of β-O-4 bond, a series of methoxyphenyl type β-O-4 dimer model compounds with different localized methoxyl gro... In order to better understand the specific substituent effects on the electrochemical oxidation process of β-O-4 bond, a series of methoxyphenyl type β-O-4 dimer model compounds with different localized methoxyl groups, including 2-(2-methoxyphenoxy)-1-phenylethanone, 2-(2-methoxyphenoxy)-1-phenylethanol, 2-(2-methoxyphenoxy)-1-(4-methoxyphenyl)ethanone, 2-(2-methoxyphenoxy)-1-(4-methoxyphenyl)ethanol, 2-(2,6-dimethoxyphenoxy)-1-(4-methoxyphenyl)ethanone, 2-(2,6-dimethoxyphenoxy)-1-(4-methoxyphenyl)ethanol have been selected and their electrochemical properties have been studied experimentally by cyclic voltammetry, and FT-IR spectroelectrochemistry. Combining with electrolysis products distribution analysis and density functional theory calculations, oxidation mechanisms of all six model dimers have been explored. In particular, a total effect from substituents of both para-methoxy(on the aryl ring closing to Cα) and Cα-OH on the oxidation mechanisms has been clearly observed, showing a significant selectivity on the Cα-Cβbond cleavage induced by electrochemical oxidations. 展开更多
关键词 Lignin model compounds β-O-4 dimers Electrochemical oxidation Oxidation mechanisms Substituent effect
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Interplay between temperature-dependent strengthening mechanisms and mechanical stability in high-performance austenitic stainless steels
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作者 Mohammad Javad Sohrabi Hamed Mirzadeh +3 位作者 Saeed Sadeghpour Milad Zolfipour Aghdam Abdol Reza Geranmayeh Reza Mahmudi 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第10期2182-2188,共7页
The effects of deformation temperature on the transformation-induced plasticity(TRIP)-aided 304L,twinning-induced plasti-city(TWIP)-assisted 316L,and highly alloyed stable 904L austenitic stainless steels were compare... The effects of deformation temperature on the transformation-induced plasticity(TRIP)-aided 304L,twinning-induced plasti-city(TWIP)-assisted 316L,and highly alloyed stable 904L austenitic stainless steels were compared for the first time to tune the mechan-ical properties,strengthening mechanisms,and strength-ductility synergy.For this purpose,the scanning electron microscopy(SEM),electron backscattered diffraction(EBSD),X-ray diffraction(XRD),tensile testing,work-hardening analysis,and thermodynamics calcu-lations were used.The induced plasticity effects led to a high temperature-dependency of work-hardening behavior in the 304L and 316L stainless steels.As the deformation temperature increased,the metastable 304L stainless steel showed the sequence of TRIP,TWIP,and weakening of the induced plasticity mechanism;while the disappearance of the TWIP effect in the 316L stainless steel was also observed.However,the solid-solution strengthening in the 904L superaustenitic stainless steel maintained the tensile properties over a wide temper-ature range,surpassing the performance of 304L and 316L stainless steels.In this regard,the dependency of the total elongation on the de-formation temperature was less pronounced for the 904L alloy due to the absence of additional plasticity mechanisms.These results re-vealed the importance of solid-solution strengthening and the associated high friction stress for superior mechanical behavior over a wide temperature range. 展开更多
关键词 austenitic stainless steels mechanical behavior stacking fault energy METASTABILITY mechanical twinning
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Activity-dependent mechanisms of neuroprotection:promising avenues against dementia
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作者 Davide Tampellini 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1409-1410,共2页
The study of the brain and its complex functions is highly fascinating and,at the same time,extremely important.Indeed,furthering our understanding of the biology of neurons and synapses is a prerequisite to uncover t... The study of the brain and its complex functions is highly fascinating and,at the same time,extremely important.Indeed,furthering our understanding of the biology of neurons and synapses is a prerequisite to uncover the mechanisms involved in memory formation and the coordination of movement as well as their alterations occurring in several neurological disorders. 展开更多
关键词 alterations mechanisms NEUROLOGICAL
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Contribution of mechanical forces to structural synaptic plasticity:insights from 3D cellular motility mechanisms
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作者 Rita O.Teodoro Mafalda Ribeiro Ramos Lara Carvalho 《Neural Regeneration Research》 SCIE CAS 2025年第7期1995-1996,共2页
Cells,tissues,and organs are constantly subjected to the action of mechanical forces from the extracellular environment-and the nervous system is no exception.Cell-intrinsic properties such as membrane lipid compositi... Cells,tissues,and organs are constantly subjected to the action of mechanical forces from the extracellular environment-and the nervous system is no exception.Cell-intrinsic properties such as membrane lipid composition,abundance of mechanosensors,and cytoskeletal dynamics make cells more or less likely to sense these forces.Intrinsic and extrinsic cues are integrated by cells and this combined information determines the rate and dynamics of membrane protrusion growth or retraction(Yamada and Sixt,2019).Cell protrusions are extensions of the plasma membrane that play crucial roles in diverse contexts such as cell migration and neuronal synapse formation.In the nervous system,neurons are highly dynamic cells that can change the size and number of their pre-and postsynaptic elements(called synaptic boutons and dendritic spines,respectively),in response to changes in the levels of synaptic activity through a process called plasticity.Synaptic plasticity is a hallmark of the nervous system and is present throughout our lives,being required for functions like memory formation or the learning of new motor skills(Minegishi et al.,2023;Pillai and Franze,2024). 展开更多
关键词 PLASTICITY STRUCTURAL mechanisms
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Obituary:Prof.Yun Zhang(1963-2023)-A scientist focused on toxins and their underlying mechanisms to decipher human diseases
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作者 Wenhui Lee Ren Lai 《Zoological Research》 SCIE CSCD 2024年第1期230-232,共3页
Prof.Yun Zhang was born on 9 July 1963 in Kunming,Yunnan,China,during a tumultuous period which he often referenced.Throughout his life,he harbored a steadfast belief in using knowledge to unravel the mysteries of hum... Prof.Yun Zhang was born on 9 July 1963 in Kunming,Yunnan,China,during a tumultuous period which he often referenced.Throughout his life,he harbored a steadfast belief in using knowledge to unravel the mysteries of human diseases.His educational journey was marked by frequent changes in schools due to his parents’occupational relocations.However,despite these challenges,he consistently displayed diligence and was admitted to the East China University of Science and Technology,Shanghai,after completing high school in 1980.He remained an active and loyal member of the School of Biotechnology at the university. 展开更多
关键词 admitted harbor mechanisms
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Chlorfenapyr poisoning:mechanisms,clinical presentations,and treatment strategies
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作者 Ji Cheng Yulu Chen +4 位作者 Weidong Wang Xueqi Zhu Zhenluo Jiang Peng Liu Liwen Du 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第3期214-219,共6页
BACKGROUND:Chlorfenapyr is used to kill insects that are resistant to organophosphorus insecticides.Chlorfenapyr poisoning has a high mortality rate and is difficult to treat.This article aims to review the mechanisms... BACKGROUND:Chlorfenapyr is used to kill insects that are resistant to organophosphorus insecticides.Chlorfenapyr poisoning has a high mortality rate and is difficult to treat.This article aims to review the mechanisms,clinical presentations,and treatment strategies for chlorfenapyr poisoning.DATA RESOURCES:We conducted a review of the literature using PubMed,Web of Science,and SpringerLink from their beginnings to the end of October 2023.The inclusion criteria were systematic reviews,clinical guidelines,retrospective studies,and case reports on chlorfenapyr poisoning that focused on its mechanisms,clinical presentations,and treatment strategies.The references in the included studies were also examined to identify additional sources.RESULTS:We included 57 studies in this review.Chlorfenapyr can be degraded into tralopyril,which is more toxic and reduces energy production by inhibiting the conversion of adenosine diphosphate to adenosine triphosphate.High fever and altered mental status are characteristic clinical presentations of chlorfenapyr poisoning.Once it occurs,respiratory failure occurs immediately,ultimately leading to cardiac arrest and death.Chlorfenapyr poisoning is diflcult to treat,and there is no specific antidote.CONCLUSION:Chlorfenapyr is a new pyrrole pesticide.Although it has been identified as a moderately toxic pesticide by the World Health Organization(WHO),the mortality rate of poisoned patients is extremely high.There is no specific antidote for chlorfenapyr poisoning.Therefore,based on the literature review,future efforts to explore rapid and effective detoxification methods,reconstitute intracellular oxidative phosphorylation couplings,identify early biomarkers of chlorfenapyr poisoning,and block the conversion of chlorfenapyr to tralopyril may be helpful for emergency physicians in the diagnosis and treatment of this disease. 展开更多
关键词 Chlorfenapyr poisoning mechanISM Clinical presentation TREATMENT
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Controllable Condensation of Aromatics and Its Mechanisms in Carbonization
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作者 Fan Xi Wang Chunlu +3 位作者 Luo Yang Ren Qiang Shen Haiping Long Jun 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第1期34-46,共13页
In order to obtain liquefied products with higher yields of aromatic molecules to produce mesophase pitch,a good understanding of the relevant reaction mechanisms is required.Reactive molecular dynamics simulations we... In order to obtain liquefied products with higher yields of aromatic molecules to produce mesophase pitch,a good understanding of the relevant reaction mechanisms is required.Reactive molecular dynamics simulations were used to study the thermal reactions of pyrene,1-methylpyrene,7,8,9,10-tetrahydrobenzopyrene,and mixtures of pyrene with 1-octene,cyclohexene,or styrene.The reactant conversion rates,reaction rates,and product distributions were calculated and compared,and the mechanisms were analyzed and discussed.The results demonstrated that methyl and naphthenic structures in aromatics might improve the conversion rates of reactants in hydrogen transfer processes,but their steric hindrances prohibited the generation of high polymers.The naphthenic structures could generate more free radicals and presented a more obvious inhibition effect on the condensation of polymers compared with the methyl side chains.It was discovered that when different olefins were mixed with pyrene,1-octene primarily underwent pyrolysis reactions,whereas cyclohexene mainly underwent hydrogen transfer reactions with pyrene and styrene,mostly producing superconjugated biradicals through condensation reactions with pyrene.In the mixture systems,the olefins scattered aromatic molecules,hindering the formation of pyrene trimers and higher polymers.According to the reactive molecular dynamics simulations,styrene may enhance the yield of dimer and enable the controlled polycondensation of pyrene. 展开更多
关键词 CARBONIZATION controllable condensation AROMATICS mechanisms molecular simulation
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Evaluation on Configuration Stiffness of Overconstrained 2R1T Parallel Mechanisms
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作者 Xuejian Ma Zhenghe Xu +3 位作者 Yundou Xu Yu Wang Jiantao Yao Yongsheng Zhao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期62-82,共21页
Currently,two rotations and one translation(2R1T)three-degree-of-freedom(DOF)parallel mechanisms(PMs)are widely applied in five-DOF hybrid machining robots.However,there is a lack of an effective method to evaluate th... Currently,two rotations and one translation(2R1T)three-degree-of-freedom(DOF)parallel mechanisms(PMs)are widely applied in five-DOF hybrid machining robots.However,there is a lack of an effective method to evaluate the configuration stiffness of mechanisms during the mechanism design stage.It is a challenge to select appropriate 2R1T PMs with excellent stiffness performance during the design stage.Considering the operational status of 2R1T PMs,the bending and torsional stiffness are considered as indices to evaluate PMs'configuration stiffness.Subsequently,a specific method is proposed to calculate these stiffness indices.Initially,the various types of structural and driving stiffness for each branch are assessed and their specific values defined.Subsequently,a rigid-flexible coupled force model for the over-constrained 2R1T PM is established,and the proposed evaluation method is used to analyze the configuration stiffness of the five 2R1T PMs in the entire workspace.Finally,the driving force and constraint force of each branch in the whole working space are calculated to further elucidate the stiffness evaluating results by using the proposed method above.The obtained results demonstrate that the bending and torsional stiffness of the 2RPU/UPR/RPR mechanism along the x and y-directions are larger than the other four mechanisms. 展开更多
关键词 Parallel mechanism STIFFNESS Over-constrained Three degrees of freedom
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Bioactivities,Mechanisms,Production,and Potential Application of Bile Acids in Preventing and Treating Infectious Diseases
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作者 Shuang Liu Shuo Yang +3 位作者 Biljan Blazekovic Lu Li Jidan Zhang Yi Wang 《Engineering》 SCIE EI CAS CSCD 2024年第7期13-26,共14页
Infectious diseases are a global public health problem,with emerging and re-emerging infectious diseases on the rise worldwide.Therefore,their prevention and treatment are still major challenges.Bile acids are common ... Infectious diseases are a global public health problem,with emerging and re-emerging infectious diseases on the rise worldwide.Therefore,their prevention and treatment are still major challenges.Bile acids are common metabolites in both hosts and microorganisms that play a significant role in controlling the metabolism of lipids,glucose,and energy.Bile acids have historically been utilized as first-line,valuable therapeutic agents for related metabolic and hepatobiliary diseases.Notably,bile acids are the major active ingredients of cow bezoar and bear bile,which are commonly used traditional Chinese medicines(TCMs)with the therapeutic effects of clearing heat,detoxification,and relieving wind and spasm.In recent years,the promising performance of bile acids against infectious diseases has attracted attention from the scientific community.This paper reviews for the first time the biological activities,possible mechanisms,production routes,and potential applications of bile acids in the treatment and prevention of infectious diseases.Compared with previous reviews,we comprehensively summarize existing studies on the use of bile acids against infectious diseases caused by pathogenic microorganisms that are leading causes of global morbidity and mortality.In addition,to ensure a stable supply of bile acids at affordable prices,it is necessary to clarify the biosynthesis of bile acids in vivo,which will assist scientists in elucidating the accumulation of bile acids and discovering how to engineer various bile acids by means of chemosynthesis,biosynthesis,and chemoenzymatic synthesis.Finally,we explore the current challenges in the field and recommend a development strategy for bile-acid-based drugs and the sustainable production of bile acids.The presented studies suggest that bile acids are potential novel therapeutic agents for managing infectious diseases and can be artificially synthesized in a sustainable way. 展开更多
关键词 Bile acids Infectious diseases BIOACTIVITIES mechanisms Anti-infective agents
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Mechanisms and active substances of targeting lipid peroxidation in ferroptosis regulation
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作者 Hui Chen Lingli Chen Wenjun Wang 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2502-2518,共17页
Ferroptosis is a novel form of cell death driven by iron-dependent lipid peroxidation and it is implicated in various diseases,such as liver disease,acute kidney injury,cardiovascular disease,neurodegenerative disease... Ferroptosis is a novel form of cell death driven by iron-dependent lipid peroxidation and it is implicated in various diseases,such as liver disease,acute kidney injury,cardiovascular disease,neurodegenerative disease and cancer.Lipid-based reactive oxygen species(ROS),particularly lipid hydroperoxides in the cellular membrane can lead to membrane disruption and cell death mediated by ferroptosis.There are three necessary stages involving in the process of lipid peroxidation regulation in ferroptosis,including the synthesis of membrane phospholipids,initiation of lipid peroxidation and clearance of lipid peroxides.In this review,we summarized the molecular modulation mechanisms of lipid peroxidation in ferroptosis from the above three stages,as well as various ferroptosis modulators targeting lipid peroxidation,including commonly used products,natural bioactive compounds and selenocompounds.Collectively,these findings suggest the vital role of lipid peroxidation in ferroptosis,and targeting lipid peroxidation in ferroptosis is potential to treat ferroptosis-associated diseases. 展开更多
关键词 Ferroptosis Lipid peroxidation mechanisms Natural bioactive compounds Selenocompounds
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Evolution model and failure mechanisms of rainfall-induced cracked red clay slopes:insights from Xinshao County,China
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作者 JIAO Weizhi ZHANG Ming +4 位作者 LI Peng XIE Junjin PANG Haisong LIU Fuxing YANG Long 《Journal of Mountain Science》 SCIE CSCD 2024年第3期867-881,共15页
Red clay landslides are widely distributed worldwide,resulting in severe loss of life and property.Although rainfall-induced red clay slopes have received extensive attention,the role of cracks in the evolutionary pro... Red clay landslides are widely distributed worldwide,resulting in severe loss of life and property.Although rainfall-induced red clay slopes have received extensive attention,the role of cracks in the evolutionary process of red clay slopes and their connection to failure mechanisms is still poorly understood.A comprehensive approach integrating field investigation,laboratory tests,and numerical simulations was conducted to study the 168 red clay landslides in Xinshao County,China.The results show that red clay is prone to forming cracks at high moisture content due to its low swelling and high shrinkage properties.The failure mode of red clay slopes can be summarized in three stages:crack generation,slope excavation,and slope failure.Furthermore,the retrospective analysis and numerical simulations of the typical landslide in Guanchong indicated that intense rainfall primarily impacts the shallow layer of soil within approximately 0.5 m on the intact slope.However,cracks change the pattern of rainfall infiltration in the slope.Rainwater infiltrates rapidly through the preferential channels induced by the cracks rather than uniformly and slowly from the slope surface.This results in a significant increase in both the depth of infiltration and the saturated zone area of the cracked slope,reaching 3.8 m and 36.2 m^(2),respectively.Consequently,the factor of safety of the slope decreases by 13.4%compared to the intact slope,ultimately triggering landslides.This study can provide valuable insights into understanding the failure mechanisms of red clay slopes in China and other regions with similar geological settings. 展开更多
关键词 Red clay slopes Cracks Preferential flow Failure mechanism
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Seed Storability in Rice: Physiological Foundations, Molecular Mechanisms, and Applications in Breeding
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作者 ZHOU Tianshun YU Dong +3 位作者 WU Liubing XU Yusheng DUAN Meijuan YUAN Dingyang 《Rice science》 SCIE CSCD 2024年第4期401-416,I0023-I0024,共18页
Long-term storage of crop seeds is critical for the conservation of germplasm resources, ensuring food supply, and supporting sustainable production. Rice, as a major food staple, has a substantial stock for consumpti... Long-term storage of crop seeds is critical for the conservation of germplasm resources, ensuring food supply, and supporting sustainable production. Rice, as a major food staple, has a substantial stock for consumption and production worldwide. However, its food value and seed viability tend to decline during storage. Understanding the physiological responses and molecular mechanisms of aging tolerance forms the basis for enhancing seed storability in rice. This review outlines the latest progress in influential factors, evaluation methods, and identification indices of seed storability. It also discusses the physiological consequences, molecular mechanisms, and strategies for breeding aging-tolerant rice in detail. Finally, it highlights challenges in seed storability research that require future attention. This review offers a theoretical foundation and research direction for uncovering the mechanisms behind seed storability and breeding aging-tolerant rice. 展开更多
关键词 RICE seed storability physiological response molecular mechanism aging-tolerant breeding
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Enhancing Image Description Generation through Deep Reinforcement Learning:Fusing Multiple Visual Features and Reward Mechanisms
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作者 Yan Li Qiyuan Wang Kaidi Jia 《Computers, Materials & Continua》 SCIE EI 2024年第2期2469-2489,共21页
Image description task is the intersection of computer vision and natural language processing,and it has important prospects,including helping computers understand images and obtaining information for the visually imp... Image description task is the intersection of computer vision and natural language processing,and it has important prospects,including helping computers understand images and obtaining information for the visually impaired.This study presents an innovative approach employing deep reinforcement learning to enhance the accuracy of natural language descriptions of images.Our method focuses on refining the reward function in deep reinforcement learning,facilitating the generation of precise descriptions by aligning visual and textual features more closely.Our approach comprises three key architectures.Firstly,it utilizes Residual Network 101(ResNet-101)and Faster Region-based Convolutional Neural Network(Faster R-CNN)to extract average and local image features,respectively,followed by the implementation of a dual attention mechanism for intricate feature fusion.Secondly,the Transformer model is engaged to derive contextual semantic features from textual data.Finally,the generation of descriptive text is executed through a two-layer long short-term memory network(LSTM),directed by the value and reward functions.Compared with the image description method that relies on deep learning,the score of Bilingual Evaluation Understudy(BLEU-1)is 0.762,which is 1.6%higher,and the score of BLEU-4 is 0.299.Consensus-based Image Description Evaluation(CIDEr)scored 0.998,Recall-Oriented Understudy for Gisting Evaluation(ROUGE)scored 0.552,the latter improved by 0.36%.These results not only attest to the viability of our approach but also highlight its superiority in the realm of image description.Future research can explore the integration of our method with other artificial intelligence(AI)domains,such as emotional AI,to create more nuanced and context-aware systems. 展开更多
关键词 Image description deep reinforcement learning attention mechanism
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A comparative study on kinetics and dynamics of two dump truck lifting mechanisms using MATLAB simscape
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作者 Thong Duc Hong Minh Quang Pham +2 位作者 Son Cong Tran Lam Quang Tran Truong Thanh Nguyen 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第2期146-156,共11页
In this paper,two lifting mechanism models with opposing placements,which use the same hydraulic hoist model and have the same angle of 50°,have been developed.The mechanical and hydraulic simulation models are e... In this paper,two lifting mechanism models with opposing placements,which use the same hydraulic hoist model and have the same angle of 50°,have been developed.The mechanical and hydraulic simulation models are established using MATLAB Simscape to analyze their kinetics and dynamics in the lifting and holding stages.The simulation findings are compared to the analytical calculation results in the steady state,and both methods show good agreement.In the early lifting stage,Model 1 produces greater force and discharges goods in the container faster than Model 2.Meanwhile,Model 2 reaches a higher force and ejects goods from the container cleaner than its counterpart at the end lifting stage.The established simulation models can consider the effects of dynamic loads due to inertial moments and forces generated during the system operation.It is crucial in studying,designing,and optimizing the structure of hydraulic-mechanical systems. 展开更多
关键词 Dump truck Lifting mechanism HYDRAULIC MATLAB Simscape Kinetic dynamic analysis
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Pharmacological effects of volatile oil from chrysanthemum and its associated mechanisms:a review
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作者 Jing Zhang Weiqiang Su +6 位作者 Nina Filipczak Ying Luo Anping Wan Yao He Shijuan Yan Xiang Li Ming Yang 《Acupuncture and Herbal Medicine》 2024年第1期79-91,共13页
Volatile oil(VO)is the main chemical component of common plants in Chrysanthemum genus,and it possesses several beneficial pharmacological properties,including bacteriostatic,antioxidant,anti-tumor,anti-inflammatory,a... Volatile oil(VO)is the main chemical component of common plants in Chrysanthemum genus,and it possesses several beneficial pharmacological properties,including bacteriostatic,antioxidant,anti-tumor,anti-inflammatory,antipyretic,analgesic,antiosteoporotic,antihypertensive,sedative,and hypnotic effects.To date,research on the effective components of Chrysanthemum extract has mainly focused on flavonoids,whereas limited data are available on the chemical constituents and underlying mechanisms of action of the VO components.In this review,the pharmacological activities and mechanisms of VO are comprehensively reviewed with the aim of providing a foundation for further development for medicinal,aromatherapy,and diet therapy applications. 展开更多
关键词 Action mechanisms CHRYSANTHEMUM Pharmacological activity Volatile oil
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Identifying the Hydrochemical Characteristics,Genetic Mechanisms and Potential Human Health Risks of Fluoride and Nitrate Enriched Groundwater in the Tongzhou District,Beijing,North China
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作者 ZHANG Shouchuan LIU Kai +2 位作者 MA Yan WANG Luyao SUN Junliang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期468-476,共9页
Fluoride and nitrate enriched groundwater are potential threats to the safety of the groundwater supply that may cause significant effects on human health and public safety,especially in aggregated population areas an... Fluoride and nitrate enriched groundwater are potential threats to the safety of the groundwater supply that may cause significant effects on human health and public safety,especially in aggregated population areas and economic hubs.This study focuses on the high F^(−)and NO_(3)^(−)concentration groundwater in Tongzhou District,Beijing,North China.A total of 36 groundwater samples were collected to analyze the hydrochemical characteristics,elucidate genetic mechanisms and evaluate the potential human health risks.The results of the analysis indicate:Firstly,most of the groundwater samples are characterized by Mg-HCO_(3) and Na-HCO_(3) with the pH ranging from 7.19 to 8.28 and TDS with a large variation across the range 471-2337 mg/L.The NO_(3)^(−)concentration in 38.89%groundwater samples and the F^(−)concentration in 66.67%groundwater samples exceed the permissible limited value.Secondly,F^(−)in groundwater originates predominantly from water-rock interactions and the fluorite dissolution,which is also regulated by cation exchange,competitive adsorption of HCO_(3)−and an alkaline environment.Thirdly,the effect of sewage disposal and agricultural activities have a significant effect on high NO3-concentration,while the high F^(−)concentration is less influenced by anthropogenic activity.The alkaline environment favors nitrification,thus being conducive to the production of NO_(3)^(−).Finally,the health risk assessment is evaluated for different population groups.The results indicate that high NO_(3)^(−)and F^(−)concentration in groundwater would have the largest threat to children’s health.The findings of this study could contribute to the provision of a scientific basis for groundwater supply policy formulation relating to public health in Tongzhou District. 展开更多
关键词 fluoride concentration nitrate pollution genetic mechanism health risk assessment Tongzhou District
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Pathological mechanisms of amyotrophic lateral sclerosis
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作者 Yushu Hu Wenzhi Chen +4 位作者 Caihui Wei Shishi Jiang Shu Li Xinxin Wang Renshi Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期1036-1044,共9页
Amyotrophic lateral sclerosis refers to a neurodegenerative disease involving the motor system,the cause of which remains unexplained despite several years of research.Thus,the journey to understanding or treating amy... Amyotrophic lateral sclerosis refers to a neurodegenerative disease involving the motor system,the cause of which remains unexplained despite several years of research.Thus,the journey to understanding or treating amyotrophic lateral sclerosis is still a long one.According to current research,amyotrophic lateral sclerosis is likely not due to a single factor but rather to a combination of mechanisms mediated by complex interactions between molecular and genetic pathways.The progression of the disease involves multiple cellular processes and the interaction between different complex mechanisms makes it difficult to identify the causative factors of amyotrophic lateral sclerosis.Here,we review the most common amyotrophic lateral sclerosis-associated pathogenic genes and the pathways involved in amyotrophic lateral sclerosis,as well as summarize currently proposed potential mechanisms responsible for amyotrophic lateral sclerosis disease and their evidence for involvement in amyotrophic lateral sclerosis.In addition,we discuss current emerging strategies for the treatment of amyotrophic lateral sclerosis.Studying the emergence of these new therapies may help to further our understanding of the pathogenic mechanisms of the disease. 展开更多
关键词 amyotrophic lateral sclerosis cellular pathways disease mechanisms motor neuron neurodegenerative disease
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