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Integrated ribosome and proteome analyses reveal insights into sevoflurane-induced long-term social behavior and cognitive dysfunctions through ADNP inhibition in neonatal mice 被引量:1
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作者 Li-Rong Liang Bing Liu +9 位作者 Shu-Hui Cao You-Yi Zhao Tian Zeng Mei-Ting Zhai Ze Fan Dan-Yi He San-Xin Ma Xiao-Tong Shi Yao Zhang Hui Zhang 《Zoological Research》 SCIE CSCD 2024年第3期663-678,共16页
A growing number of studies have demonstrated that repeated exposure to sevoflurane during development results in persistent social abnormalities and cognitive impairment.Davunetide,an active fragment of the activity-... A growing number of studies have demonstrated that repeated exposure to sevoflurane during development results in persistent social abnormalities and cognitive impairment.Davunetide,an active fragment of the activity-dependent neuroprotective protein(ADNP),has been implicated in social and cognitive protection.However,the potential of davunetide to attenuate social deficits following sevoflurane exposure and the underlying developmental mechanisms remain poorly understood.In this study,ribosome and proteome profiles were analyzed to investigate the molecular basis of sevoflurane-induced social deficits in neonatal mice.The neuropathological basis was also explored using Golgi staining,morphological analysis,western blotting,electrophysiological analysis,and behavioral analysis.Results indicated that ADNP was significantly down-regulated following developmental exposure to sevoflurane.In adulthood,anterior cingulate cortex(ACC)neurons exposed to sevoflurane exhibited a decrease in dendrite number,total dendrite length,and spine density.Furthermore,the expression levels of Homer,PSD95,synaptophysin,and vglut2 were significantly reduced in the sevoflurane group.Patch-clamp recordings indicated reductions in both the frequency and amplitude of miniature excitatory postsynaptic currents(mEPSCs).Notably,davunetide significantly ameliorated the synaptic defects,social behavior deficits,and cognitive impairments induced by sevoflurane.Mechanistic analysis revealed that loss of ADNP led to dysregulation of Ca^(2+)activity via the Wnt/β-catenin signaling,resulting in decreased expression of synaptic proteins.Suppression of Wnt signaling was restored in the davunetide-treated group.Thus,ADNP was identified as a promising therapeutic target for the prevention and treatment of neurodevelopmental toxicity caused by general anesthetics.This study provides important insights into the mechanisms underlying social and cognitive disturbances caused by sevoflurane exposure in neonatal mice and elucidates the regulatory pathways involved. 展开更多
关键词 Davunetide SEVOFLURANE Abnormal social behaviors ADNP NEUROTOXICITY
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Dose-response associations,physical activity intensity and mortality risk:A narrative review 被引量:1
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作者 Ulf Ekelund Miguel Adriano Sanchez-Lastra +1 位作者 Knut Eirik Dalene Jakob Tarp 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期24-29,共6页
Physical activity is consistently associated with reduced mortality,decreased risk for non-communicable diseases,and improved mental health in observational studies.Randomized controlled trials and observational Mende... Physical activity is consistently associated with reduced mortality,decreased risk for non-communicable diseases,and improved mental health in observational studies.Randomized controlled trials and observational Mendelian randomization studies support causal links between physical activity and health outcomes.However,the scarcity of evidence from randomized controlled trials,along with their inherent challenges like exposure contrasts,healthy volunteer biases,loss to follow-up,and limited real-world dose-response data,warrants a comprehensive approach.This review advocates synthesizing insights from diverse study designs to better understand the causal relationship between physical activity,mortality risk,and other health outcomes.Additionally,it summarizes recent research since the publication of current physical activity recommendations.Novel observational studies utilizing device-measured physical activity underscore the importance of every minute of activity and suggest that all intensity levels confer health benefits,with vigorous-intensity potentially requiring lower volumes for substantial benefits.Future guidelines,informed by device-measured physical activity studies,may offer refined age-specific recommendations,emphasize vigorous-intensity physical activity,and include daily step counts as a simple,easily assessable metric using commercial wearables. 展开更多
关键词 Accelerometers Non-communicable diseases Public health Sedentary behavior
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Neurophysiological, histological, and behavioral characterization of animal models of distraction spinal cord injury: a systematic review 被引量:1
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作者 Bo Han Weishi Liang +4 位作者 Yong Hai Duan Sun Hongtao Ding Yihan Yang Peng Yin 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第3期563-570,共8页
Distraction spinal cord injury is caused by some degree of distraction or longitudinal tension on the spinal cord and commonly occurs in patients who undergo corrective operation for severe spinal deformity.With the i... Distraction spinal cord injury is caused by some degree of distraction or longitudinal tension on the spinal cord and commonly occurs in patients who undergo corrective operation for severe spinal deformity.With the increased degree and duration of distraction,spinal cord injuries become more serious in terms of their neurophysiology,histology,and behavior.Very few studies have been published on the specific characteristics of distraction spinal cord injury.In this study,we systematically review 22 related studies involving animal models of distraction spinal cord injury,focusing particularly on the neurophysiological,histological,and behavioral characteristics of this disease.In addition,we summarize the mechanisms underlying primary and secondary injuries caused by distraction spinal cord injury and clarify the effects of different degrees and durations of distraction on the primary injuries associated with spinal cord injury.We provide new concepts for the establishment of a model of distraction spinal cord injury and related basic research,and provide reference guidelines for the clinical diagnosis and treatment of this disease. 展开更多
关键词 animal models behavior DISTRACTION heterogeneity HISTOLOGY mechanism NEUROPHYSIOLOGY spinal cord injury systematic review tension
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A Comparative Study on the Post-Buckling Behavior of Reinforced Thermoplastic Pipes(RTPs)Under External Pressure Considering Progressive Failure 被引量:1
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作者 DING Xin-dong WANG Shu-qing +1 位作者 LIU Wen-cheng YE Xiao-han 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期233-246,共14页
The collapse pressure is a key parameter when RTPs are applied in harsh deep-water environments.To investigate the collapse of RTPs,numerical simulations and hydrostatic pressure tests are conducted.For the numerical ... The collapse pressure is a key parameter when RTPs are applied in harsh deep-water environments.To investigate the collapse of RTPs,numerical simulations and hydrostatic pressure tests are conducted.For the numerical simulations,the eigenvalue analysis and Riks analysis are combined,in which the Hashin failure criterion and fracture energy stiffness degradation model are used to simulate the progressive failure of composites,and the“infinite”boundary conditions are applied to eliminate the boundary effects.As for the hydrostatic pressure tests,RTP specimens were placed in a hydrostatic chamber after filled with water.It has been observed that the cross-section of the middle part collapses when it reaches the maximum pressure.The collapse pressure obtained from the numerical simulations agrees well with that in the experiment.Meanwhile,the applicability of NASA SP-8007 formula on the collapse pressure prediction was also discussed.It has a relatively greater difference because of the ignorance of the progressive failure of composites.For the parametric study,it is found that RTPs have much higher first-ply-failure pressure when the winding angles are between 50°and 70°.Besides,the effect of debonding and initial ovality,and the contribution of the liner and coating are also discussed. 展开更多
关键词 reinforced thermoplastic pipes post-buckling behavior progressive failure of composites DEBONDING initial ovality
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Development of a convolutional neural network based geomechanical upscaling technique for heterogeneous geological reservoir 被引量:1
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作者 Zhiwei Ma Xiaoyan Ou Bo Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2111-2125,共15页
Geomechanical assessment using coupled reservoir-geomechanical simulation is becoming increasingly important for analyzing the potential geomechanical risks in subsurface geological developments.However,a robust and e... Geomechanical assessment using coupled reservoir-geomechanical simulation is becoming increasingly important for analyzing the potential geomechanical risks in subsurface geological developments.However,a robust and efficient geomechanical upscaling technique for heterogeneous geological reservoirs is lacking to advance the applications of three-dimensional(3D)reservoir-scale geomechanical simulation considering detailed geological heterogeneities.Here,we develop convolutional neural network(CNN)proxies that reproduce the anisotropic nonlinear geomechanical response caused by lithological heterogeneity,and compute upscaled geomechanical properties from CNN proxies.The CNN proxies are trained using a large dataset of randomly generated spatially correlated sand-shale realizations as inputs and simulation results of their macroscopic geomechanical response as outputs.The trained CNN models can provide the upscaled shear strength(R^(2)>0.949),stress-strain behavior(R^(2)>0.925),and volumetric strain changes(R^(2)>0.958)that highly agree with the numerical simulation results while saving over two orders of magnitude of computational time.This is a major advantage in computing the upscaled geomechanical properties directly from geological realizations without the need to perform local numerical simulations to obtain the geomechanical response.The proposed CNN proxybased upscaling technique has the ability to(1)bridge the gap between the fine-scale geocellular models considering geological uncertainties and computationally efficient geomechanical models used to assess the geomechanical risks of large-scale subsurface development,and(2)improve the efficiency of numerical upscaling techniques that rely on local numerical simulations,leading to significantly increased computational time for uncertainty quantification using numerous geological realizations. 展开更多
关键词 Upscaling Lithological heterogeneity Convolutional neural network(CNN) Anisotropic shear strength Nonlinear stressestrain behavior
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UHPC-RC节段组合梁的抗弯性能分析
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作者 严靖 陈亮 黄润钺 《合肥工业大学学报(自然科学版)》 CAS 北大核心 2024年第2期207-213,共7页
为研究低预应力度条件下,不同节段接缝的超高性能混凝土-钢筋混凝土(ultra-high performance concrete-reinforced concrete,UHPC-RC)组合梁的抗弯性能,文章基于ABAQUS有限元软件,建立UHPC-RC节段组合梁的基准有限元模型,并利用已有的... 为研究低预应力度条件下,不同节段接缝的超高性能混凝土-钢筋混凝土(ultra-high performance concrete-reinforced concrete,UHPC-RC)组合梁的抗弯性能,文章基于ABAQUS有限元软件,建立UHPC-RC节段组合梁的基准有限元模型,并利用已有的试验数据验证该模型的合理性。节段接缝分别为平面干接缝、平面胶接缝、齿键干接缝和齿键胶接缝,在基准有限元模型的基础上,进一步研究节段接缝类型对组合梁抗弯性能的影响。研究发现,在四点受弯加载方式下,接缝的几何特征(平面或齿键)对组合梁的极限荷载和开裂荷载影响较小,环氧树脂胶的使用对组合梁的抗弯性能影响较大。 展开更多
关键词 桥梁工程 超高性能混凝土-钢筋混凝土(UHPC-RC) 节段组合梁 节段接缝 ABAQUS有限元软件 cohesive behavior模型
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Cluster DetectionMethod of Endogenous Security Abnormal Attack Behavior in Air Traffic Control Network
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作者 Ruchun Jia Jianwei Zhang +2 位作者 Yi Lin Yunxiang Han Feike Yang 《Computers, Materials & Continua》 SCIE EI 2024年第5期2523-2546,共24页
In order to enhance the accuracy of Air Traffic Control(ATC)cybersecurity attack detection,in this paper,a new clustering detection method is designed for air traffic control network security attacks.The feature set f... In order to enhance the accuracy of Air Traffic Control(ATC)cybersecurity attack detection,in this paper,a new clustering detection method is designed for air traffic control network security attacks.The feature set for ATC cybersecurity attacks is constructed by setting the feature states,adding recursive features,and determining the feature criticality.The expected information gain and entropy of the feature data are computed to determine the information gain of the feature data and reduce the interference of similar feature data.An autoencoder is introduced into the AI(artificial intelligence)algorithm to encode and decode the characteristics of ATC network security attack behavior to reduce the dimensionality of the ATC network security attack behavior data.Based on the above processing,an unsupervised learning algorithm for clustering detection of ATC network security attacks is designed.First,determine the distance between the clustering clusters of ATC network security attack behavior characteristics,calculate the clustering threshold,and construct the initial clustering center.Then,the new average value of all feature objects in each cluster is recalculated as the new cluster center.Second,it traverses all objects in a cluster of ATC network security attack behavior feature data.Finally,the cluster detection of ATC network security attack behavior is completed by the computation of objective functions.The experiment took three groups of experimental attack behavior data sets as the test object,and took the detection rate,false detection rate and recall rate as the test indicators,and selected three similar methods for comparative test.The experimental results show that the detection rate of this method is about 98%,the false positive rate is below 1%,and the recall rate is above 97%.Research shows that this method can improve the detection performance of security attacks in air traffic control network. 展开更多
关键词 Air traffic control network security attack behavior cluster detection behavioral characteristics information gain cluster threshold automatic encoder
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Gut microbiome and serum metabolome analyses identify Bacteroides fragilis as regulators of serotonin content and PRL secretion in broody geese
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作者 Yu Zhang Ning Zhou +7 位作者 Jia Wu Lina Song Qiang Bao Kaiqi Weng Yang Zhang Wanwipa Vongsangnak Guohong Chen Qi Xu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第6期2033-2051,共19页
Broody behavior is regulated by hypothalamic prolactin secretion,which seriously affects egg production in poulty production.Numerous studies have provided evidence that animal behavior is governed by dynamic bidirect... Broody behavior is regulated by hypothalamic prolactin secretion,which seriously affects egg production in poulty production.Numerous studies have provided evidence that animal behavior is governed by dynamic bidirectional communication between specific gut bacteria and their host via the brain-gut-microbiome axis.However,little research focused on how the gut microbiota influence broody behavior in poultry.In this study,Zhedong white geese in laying and brooding phases were selected.Ten differentially abundant bacteria in cecum were detected between brooding and laying geese through metagenomic analyses and 16S rRNA sequencing(P<0.05),and Bacteroides fragilis was specifically identified as a key driver species in the brooding geese.Moverover,the serum metabolites were quantified,and the 313 differentially abundant metabolites were found between the two groups of different physiological geese.They were primarily enriched in the tryptophan metabolism pathways.Pearson correlation analyses revealed there was a significant positive correlation between B.fragilis abundance and the context of 11 tryptophan metabolism-related metabolites(such as serotonin,etc.)in broody geese,which hinted that those tryptophan metabolites might be produced or driven by B.fragilis.Finally,the serum hormone levels were also measured.We found there was a positive correlation between B.fragilis abundance and content of serotonin.Besides,prolactin secreted by the pituitary gland was greater in brooding geese than that in laying geese,which was also highly correlated with B.fragilis abundance.This result implied that B.fragilis could promote the secretion of prolactin by the pituitary gland.Together,the current study findings provided the information on gut microbiota influencing broody behavior,B.fragilis produced or driven more serum serotonin,and stimulated the pituitary gland to secret more prolactin,which potentially offered a new enlightenment for the intervention of broody behavior in poultry. 展开更多
关键词 GEESE broody behavior gut microbiota SEROTONIN PROLACTIN
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Coke behavior with H_(2)O in a hydrogen-enriched blast furnace:A review
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作者 Feng Zhou Daosheng Peng +5 位作者 Kejiang Li Alberto N.Conejo Haotian Liao Zixin Xiong Dongtao Li Jianliang Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期959-976,共18页
Hydrogen-enriched blast furnace ironmaking has become an essential route to reduce CO_(2)emissions in the ironmaking process.However,hydrogen-enriched reduction produces large amounts of H_(2)O,which places new demand... Hydrogen-enriched blast furnace ironmaking has become an essential route to reduce CO_(2)emissions in the ironmaking process.However,hydrogen-enriched reduction produces large amounts of H_(2)O,which places new demands on coke quality in a blast furnace.In a hydrogen-rich blast furnace,the presence of H_(2)O promotes the solution loss reaction.This result improves the reactivity of coke,which is 20%-30%higher in a pure H_(2)O atmosphere than in a pure CO_(2)atmosphere.The activation energy range is 110-300 kJ/mol between coke and CO_(2)and 80-170 kJ/mol between coke and H_(2)O.CO_(2)and H_(2)O are shown to have different effects on coke degradation mechanisms.This review provides a comprehensive overview of the effect of H_(2)O on the structure and properties of coke.By exploring the interactions between H_(2)O and coke,several unresolved issues in the field requiring further research were identified.This review aims to provide valuable insights into coke behavior in hydrogen-rich environments and promote the further development of hydrogen-rich blast furnace ironmaking processes. 展开更多
关键词 hydrogen ironmaking coke behavior blast furnace GASIFICATION microstructure kinetics
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DYNAMICS FOR A CHEMOTAXIS MODEL WITH GENERAL LOGISTIC DAMPING AND SIGNAL DEPENDENT MOTILITY
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作者 涂馨予 穆春来 +1 位作者 邱蜀燕 张静 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期1046-1063,共18页
In this paper,we consider the fully parabolic Chemotaxis system with the general logistic source{ut=Δ(γ(v)u)+λu-μu^(k),x∈Ω,t>0,vt=△v+wz,x∈Ω,t>0,wt=-wz,x∈Ω,t>0,zt=△z-z+u,x∈Ω,t>0 whereΩ⊂ℝn(n≥... In this paper,we consider the fully parabolic Chemotaxis system with the general logistic source{ut=Δ(γ(v)u)+λu-μu^(k),x∈Ω,t>0,vt=△v+wz,x∈Ω,t>0,wt=-wz,x∈Ω,t>0,zt=△z-z+u,x∈Ω,t>0 whereΩ⊂ℝn(n≥1)is a smooth and bounded domain,λ≥0,μ≥0,κ>1,and the motility function satisfies thatγ(v)∈C3([0,∞)),γ(v)>0,γ′(v)≤0 for all v≥0.Considering the Neumann boundary condition,we obtain the global boundedness of solutions if one of the following conditions holds:(i)λ=μ=0,1≤nλ3;(ii)λ>0,μ>0,combined withκ>1,1≤n≤3 or k>n+2/4,,n>3.Moreover,we prove that the solution (u, v, w, z) exponentially converges to the constant steady state ((λ/μ)1/k-1,∫Ωv0dx+∫Ωw0dx/|Ω|,0,(λ/μ)1/k-1). 展开更多
关键词 CHEMOTAXIS signal-dependent motility logistic source boundedness asymptotic behavior
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A randomized controlled trial of Promoting Physical Activity in Regional and Remote Cancer Survivors(PPARCS)
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作者 Sarah J.Hardcastle Chloe Maxwell-Smith +12 位作者 Vinicius Cavalheri Terry Boyle Marta Leyton Román Cameron Platell Michael Levitt Christobel Saunders Frank Sardelic Sophie Nightingale Jacob McCormick Craig Lynch Paul A.Cohen Max Bulsara Dana Hince 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期81-89,共9页
Background:Physical activity(PA)is important for cancer survivors.Trials of remotely delivered interventions are needed to assist in reaching under-served non-metropolitan cancer survivors.The objective of this study ... Background:Physical activity(PA)is important for cancer survivors.Trials of remotely delivered interventions are needed to assist in reaching under-served non-metropolitan cancer survivors.The objective of this study was to ascertain whether wearable technology,coupled with health coaching was effective in increasing PA in breast and colorectal cancer survivors living in regional and remote areas in Australia.Methods:Cancer survivors from 5 states were randomized to intervention and control arms.Intervention participants were given a Fitbit Charge 2TMand received up to 6 telephone health coaching sessions.Control participants received PA print materials.Accelerometer assessments at baseline and 12 weeks measured moderate-to-vigorous PA(MVPA),light PA,and sedentary behavior.Results:Eighty-seven participants were recruited(age=63±11 years;74(85%)female).There was a significant net improvement in MVPA of 49.8 min/week,favoring the intervention group(95%confidence interval(95%CI):13.6-86.1,p=0.007).There was also a net increase in MVPA bouts of 39.5 min/week(95%CI:11.9-67.1,p=0.005),favoring the intervention group.Both groups improved light PA and sedentary behavior,but there were no between-group differences.Conclusion:This’s the first study to demonstrate that,when compared to standard practice(i.e.,PA education),a wearable technology intervention coupled with distance-based health coaching,improves MVPA in non-metropolitan cancer survivors.The results display promise for the use of scalable interventions using smart wearable technology in conjunction with phone-based health coaching to foster increased PA in geographically disadvantaged cancer survivors. 展开更多
关键词 Behavior change EXERCISE Health disparities ONCOLOGY Wearable technology
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Does the provision of live black soldier fly and yellow mealworm larvae improve Muscovy duck welfare?
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作者 Marta Gariglio Sihem Dabbou +8 位作者 Manuela Renna Ilaria Biasato Sara Bellezza Oddon Marco Meneguz Raul Daniel Miazzo Stefania Bergagna Elena Colombino Elisabetta Macchi Achille Schiavone 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期442-455,共14页
Background The provision of environmental enrichments to Muscovy ducks could reduce the expression of the aggressive behaviors.The aim of the present study was to evaluate the effects of black soldier fly(BSF)and yell... Background The provision of environmental enrichments to Muscovy ducks could reduce the expression of the aggressive behaviors.The aim of the present study was to evaluate the effects of black soldier fly(BSF)and yellow mealworm(YM)live larva provision on Muscovy duck performance,excreta corticosterone metabolites(ECM),behavior,and blood parameters.Methods A total of 1263-day-old female Muscovy ducklings were allotted to 18 pens(6 replicates/treatment,7 birds/pen)and assigned to 3 experimental treatments:a control group fed commercial feed,and two experimental treatments fed commercial feed plus the 5%(based on the expected daily feed intake,as fed basis)of BSF and YM live larvae(BSF and YM groups,respectively).A two-phase feeding program was applied:starter(from 3 to 31 days of age)and grower-finisher(from 32 to 55 days of age).The live weight,average daily gain,average daily feed intake,and feed conversion ratio were calculated.Larva consumption times were collected,and video recordings were performed during 3 periods(P)each day:the hour before(P1),during(P2),and after(P3)the larva administration.ECM were evaluated at 3,31,and 55-day-old.Finally,the total red and white blood cell counts,serum proteins,lipids,and liver and renal function serum enzymes were evaluated on 12 birds/treatment.Results The experimental treatment did not affect the growth performance of the birds(P>0.05).Larva consumption times were always similar between the two insect species,except at 14–18 days of age,were BSF larvae were consumed faster than YM larvae(P<0.001).The birds showed less walking activity during P2,and preening behavior increased in YM birds during P3.The C birds increased the attack behavior over the weeks(P<0.05).During weeks 1–3 the YM group reduced the attack frequency(P1>P3;P<0.05).Finally,the provision of live BSF and YM larvae significantly reduced the ECM at 55 days of age and the heterophil to lymphocyte ratio(P<0.05).Conclusions Live BSF and YM larva supplementation in Muscovy duck improves duck welfare,without impairing birds'growth performance. 展开更多
关键词 Behavior Cairina moschata Environmental enrichment Hermetia illucens POULTRY Tenebrio molitor WELFARE
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A bounding surface visco-plasticity model considering generalized spacing ratio of soils
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作者 Xiaosen Kang Hongjian Liao +1 位作者 Qiangbing Huang Jianbing Peng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1832-1846,共15页
The non-unique critical state of soils with time-dependent behaviors is a significant issue in geotechnical engineering problems.However,previous bounding surface plasticity models cannot predict accurately the non-un... The non-unique critical state of soils with time-dependent behaviors is a significant issue in geotechnical engineering problems.However,previous bounding surface plasticity models cannot predict accurately the non-unique critical state of soils,because the distance between the compression line and critical state line charged by strain-rate effect is basically neglected.To fill this gap,a generalized spacing ratio of soils is defined in the elasto-viscoplastic framework,and a bounding surface visco-plasticity model is formulated and verified,which can consider the generalized spacing ratio.Specifically,the generalized spacing ratio of soils reflects the distance between the compression line and the critical state line of soils with time-dependent behaviors.Then,the generalized spacing ratio is introduced into an improved anisotropic bounding surface.A new expression of the visco-plastic multiplier is derived by solving the consistency equation of an anisotropic bounding surface.In the expression,a strain rate index is proposed to account for the strain-rate effect on visco-plastic strain increment,and a visco-plastic hardening modulus is derived to predict the visco-plastic response of soils in overconsolidation conditions.The model is then verified through constant strain rate tests and creep tests.Notably,it can capture the non-unique critical states of soils with time-dependent behaviors due to the generalized spacing ratio and the creep rupture of soils due to the visco-plastic multiplier that considers the stress ratio and visco-plastic strain rate. 展开更多
关键词 Soil Constitutive model Visco-plastic behavior Strain rate CREEP ANISOTROPIC
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Collective Molecular Machines: Multidimensionality and Reconfigurability
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作者 Bin Wang Yuan Lu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第8期309-340,共32页
Molecular machines are key to cellular activity where they are involved in converting chemical and light energy into efficient mechanical work.During the last 60 years,designing molecular structures capable of generat... Molecular machines are key to cellular activity where they are involved in converting chemical and light energy into efficient mechanical work.During the last 60 years,designing molecular structures capable of generating unidirectional mechanical motion at the nanoscale has been the topic of intense research.Effective progress has been made,attributed to advances in various fields such as supramolecular chemistry,biology and nanotechnology,and informatics.However,individual molecular machines are only capable of producing nanometer work and generally have only a single functionality.In order to address these problems,collective behaviors realized by integrating several or more of these individual mechanical units in space and time have become a new paradigm.In this review,we comprehensively discuss recent developments in the collective behaviors of molecular machines.In particular,collective behavior is divided into two paradigms.One is the appropriate integration of molecular machines to efficiently amplify molecular motions and deformations to construct novel functional materials.The other is the construction of swarming modes at the supramolecular level to perform nanoscale or microscale operations.We discuss design strategies for both modes and focus on the modulation of features and properties.Subsequently,in order to address existing challenges,the idea of transferring experience gained in the field of micro/nano robotics is presented,offering prospects for future developments in the collective behavior of molecular machines. 展开更多
关键词 Molecular machines Collective control Collective behaviors DNA Biomolecular motors
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Shear behavior and off-fault damage of saw-cut smooth and tension-induced rough joints in granite
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作者 Fanzhen Meng Feili Wang +4 位作者 Louis Ngai Yuen Wong Jie Song Muzi Li Chuanqing Zhang Liming Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1216-1230,共15页
The damage of rock joints or fractures upon shear includes the surface damage occurring at the contact asperities and the damage beneath the shear surface within the host rock.The latter is commonly known as off-fault... The damage of rock joints or fractures upon shear includes the surface damage occurring at the contact asperities and the damage beneath the shear surface within the host rock.The latter is commonly known as off-fault damage and has been much less investigated than the surface damage.The main contribution of this study is to compare the results of direct shear tests conducted on saw-cut planar joints and tension-induced rough granite joints under normal stresses ranging from 1 MPa to 50 MPa.The shear-induced off-fault damages are quantified and compared with the optical microscope observation.Our results clearly show that the planar joints slip stably under all the normal stresses except under 50 MPa,where some local fractures and regular stick-slip occur towards the end of the test.Both post-peak stress drop and stick-slip occur for all the rough joints.The residual shear strength envelopes for the rough joints and the peak shear strength envelope for the planar joints almost overlap.The root mean square(RMS)of asperity height for the rough joints decreases while it increases for the planar joint after shear,and a larger normal stress usually leads to a more significant decrease or increase in RMS.Besides,the extent of off-fault damage(or damage zone)increases with normal stress for both planar and rough joints,and it is restricted to a very thin layer with limited micro-cracks beneath the planar joint surface.In comparison,the thickness of the damage zone for the rough joints is about an order of magnitude larger than that of the planar joints,and the coalesced micro-cracks are generally inclined to the shear direction with acute angles.The findings obtained in this study contribute to a better understanding on the frictional behavior and damage characteristics of rock joints or fractures with different roughness. 展开更多
关键词 Planar joint Rough joint Shear behavior Off-fault damage MICRO-CRACKS
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A Fuzzy Trust Management Mechanism with Dynamic Behavior Monitoring for Wireless Sensor Networks
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作者 Fu Shiming Zhang Ping Shi Xuehong 《China Communications》 SCIE CSCD 2024年第5期177-189,共13页
Traditional wireless sensor networks(WSNs)are typically deployed in remote and hostile environments for information collection.The wireless communication methods adopted by sensor nodes may make the network highly vul... Traditional wireless sensor networks(WSNs)are typically deployed in remote and hostile environments for information collection.The wireless communication methods adopted by sensor nodes may make the network highly vulnerable to various attacks.Traditional encryption and authentication mechanisms cannot prevent attacks launched by internal malicious nodes.The trust-based security mechanism is usually adopted to solve this problem in WSNs.However,the behavioral evidence used for trust estimation presents some uncertainties due to the open wireless medium and the inexpensive sensor nodes.Moreover,how to efficiently collect behavioral evidences are rarely discussed.To address these issues,in this paper,we present a trust management mechanism based on fuzzy logic and a cloud model.First,a type-II fuzzy logic system is used to preprocess the behavioral evidences and alleviate uncertainty.Then,the cloud model is introduced to estimate the trust values for sensor nodes.Finally,a dynamic behavior monitoring protocol is proposed to provide a balance between energy conservation and safety assurance.Simulation results demonstrate that our trust management mechanism can effectively protect the network from internal malicious attacks while enhancing the energy efficiency of behavior monitoring. 展开更多
关键词 behavior monitoring CLOUD FUZZY TRUST wireless sensor networks
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Enhancing the mechanical properties of casting eutectic high -entropy alloys via W addition
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作者 Xu Yang Dezhi Chen +3 位作者 Li Feng Gang Qin Shiping Wu Ruirun Chen 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1364-1372,共9页
The effect of W element on the microstructure evolution and mechanical properties of Al_(1.25)CoCrFeNi3 eutectic high-entropy alloy and Al_(1.25)CoCrFeNi_(3-x)W_(x)(x=0,0.05,0.1,0.3,and 0.5;atomic ratio)high-entropy a... The effect of W element on the microstructure evolution and mechanical properties of Al_(1.25)CoCrFeNi3 eutectic high-entropy alloy and Al_(1.25)CoCrFeNi_(3-x)W_(x)(x=0,0.05,0.1,0.3,and 0.5;atomic ratio)high-entropy alloys(HEAs)were explored.Results show that the Al_(1.25)CoCrFeNi_(3-x)W_(x) HEAs are composed of face-centered cubic and body-centered cubic(BCC)phases.As W content increases,the microstructure changes from eutectic to dendritic.The addition of W lowers the nucleation barrier of the BCC phase,decreases the valence electron concentration of the HEAs,and replaces Al in the BCC phase,thus facilitating the nucleation of the BCC phase.Tensile results show that the addition of W greatly improves the mechanical properties,and solid-solution,heterogeneous-interface,and second-phase strengthening are the main strengthening mechanisms.The yield strength,tensile strength,and elongation of the Al_(1.25)CoCrFeNi2.95W0.05 HEA are 601.44 MPa,1132.26 MPa,and 15.94%,respectively,realizing a balance between strength and plasti-city.The fracture mode of the Al_(1.25)CoCrFeNi_(3-x)W_(x) HEAs is ductile–brittle mixed fracture,and the crack propagates and initiates in the BCC phase.The eutectic lamellar structure impedes crack propagation and maintains plasticity. 展开更多
关键词 high-entropy alloy microstructure mechanical property fracture behavior
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Decoding complexity: the need to enhance precision and streamline spatial understanding in neuroscience
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作者 Sameehan Mahajani Armita Salahi +2 位作者 Brenda Gonzalez Charlotte Nelson Frank Hsiung 《Neural Regeneration Research》 SCIE CAS 2025年第3期801-802,共2页
Neuroscience is the ultimate frontier in our quest for a comprehensive understanding of human behavior. Since its launch in 2009, the Human Connectome Project has emerged as a pioneering force, making heroic strides i... Neuroscience is the ultimate frontier in our quest for a comprehensive understanding of human behavior. Since its launch in 2009, the Human Connectome Project has emerged as a pioneering force, making heroic strides in elucidating the intricate correlation between structural information and the functioning of the human brain. 展开更多
关键词 behavior FRONTIER DATING
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Forebrain excitatory neuron-specific loss of Brpf1 attenuates excitatory synaptic transmission and impairs spatial and fear memory
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作者 Baicheng Zhao Hang Zhang +5 位作者 Ying Liu Gaoyu Zu Yuxiao Zhang Jiayi Hu Shuai Liu Linya You 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期1133-1141,共9页
Bromodomain and plant homeodomain(PHD)finger containing protein 1(Brpf1)is an activator and scaffold protein of a multiunit complex that includes other components involving lysine acetyltransferase(KAT)6A/6B/7.Brpf1,K... Bromodomain and plant homeodomain(PHD)finger containing protein 1(Brpf1)is an activator and scaffold protein of a multiunit complex that includes other components involving lysine acetyltransferase(KAT)6A/6B/7.Brpf1,KAT6A,and KAT6B mutations were identified as the causal genes of neurodevelopmental disorders leading to intellectual disability.Our previous work revealed strong and specific expression of Brpf1 in both the postnatal and adult forebrain,especially the hippocampus,which has essential roles in learning and memory.Here,we hypothesized that Brpf1 plays critical roles in the function of forebrain excitatory neurons,and that its deficiency leads to learning and memory deficits.To test this,we knocked out Brpf1 in forebrain excitatory neurons using CaMKIIa-Cre.We found that Brpf1 deficiency reduced the frequency of miniature excitatory postsynaptic currents and downregulated the expression of genes Pcdhgb1,Slc16a7,Robo3,and Rho,which are related to neural development,synapse function,and memory,thereby damaging spatial and fear memory in mice.These findings help explain the mechanisms of intellectual impairment in patients with BRPF1 mutation. 展开更多
关键词 behavioral test Brpf1 CAMKIIa-Cre intellectual disability miniature excitatory postsynaptic current MRNA-SEQ
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Unveiling the brain’s symphony:exploring the necessity and sufficiency of neural networks in behavior control
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作者 Fernando Jose Bustos 《Neural Regeneration Research》 SCIE CAS 2025年第1期186-187,共2页
Since the pioneering work by Broca and Wernicke in the 19th century,who examined individuals with brain lesions to associate them with specific behaviors,it was evident that behaviors are complex and cannot be fully a... Since the pioneering work by Broca and Wernicke in the 19th century,who examined individuals with brain lesions to associate them with specific behaviors,it was evident that behaviors are complex and cannot be fully attributable to specific brain areas alone.Instead,they involve connectivity among brain areas,whether close or distant.At that time,this approach was considered the optimal way to dissect brain circuitry and function.These pioneering efforts opened the field to explore the necessity or sufficiency of brain areas in controlling behavior and hence dissecting brain function.However,the connectivity of the brain and the mechanisms through which various brain regions regulate specific behaviors,either individually or collaboratively,remain largely elusive.Utilizing animal models,researchers have endeavored to unravel the necessity or sufficiency of specific brain areas in influencing behavior;however,no clear associations have been firmly established. 展开更多
关键词 behavior CONNECTIVITY neural
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