In this study, the ground potential rise(GPR) phenomenon caused by a lightning current injected into a field-shaped artificial grounding grid, as well as the potential difference between two different nodes at the edg...In this study, the ground potential rise(GPR) phenomenon caused by a lightning current injected into a field-shaped artificial grounding grid, as well as the potential difference between two different nodes at the edge of the grounding grid, was observed and analyzed under artificially triggered lightning conditions. Based on circuit theory and measured current data, a π-equivalent circuit was established to simulate the transient response of the grounding grid.Nineteen return strokes from three artificially triggered lightning events were analyzed. The peak currents of the 19 return strokes range from -6.7 to -25.1 kA, and the mean value was -14.3 kA. The GPR decreased rapidly and formed a subpeak after reaching the initial peak, with the mean value of the initial peak being -148.65 kV and the mean value of the subpeak being -92.87 kV. The GPR induced by the triggered lightning currents exhibited a subpeak phenomenon. Simulation results indicate that the subpeak phenomenon is related to localized corrosion of the vertical grounding electrode. The potential difference at the grounding grid edge exhibited a multi-pulse waveform with alternating polarity, dominated by positive pulses. The peak values of both the positive and negative polarity pulses gradually decreased, with the first positive pulse displaying a significantly higher intensity than that of subsequent pulses.展开更多
Carbonyl compounds play a pivotal role in the formation of secondary pollutants such as O_(3) and SOA,signifi-cantly impacting air quality and human health.This study extended the observation period compared to previo...Carbonyl compounds play a pivotal role in the formation of secondary pollutants such as O_(3) and SOA,signifi-cantly impacting air quality and human health.This study extended the observation period compared to previous research,providing a long-term perspective on carbonyl compound variations and their environmental implica-tions.Atmospheric observations were conducted at Beijing(BJ)and Xianghe(XH)during the summer and winter months of 2018,2019,and 2023 to study the sources and impacts of carbonyl compounds in typical urban areas and peri‑urban areas.Notably,concentrations in the summer of 2023 increased compared to 2018 and 2019.The predominant carbonyl compounds—formaldehyde,acetaldehyde,and acetone—accounted for over 60%of the total.The mean values of OFP in BJ ranged from 18.55 to 58.61μg/m3,lower than those in XH(29.82 to 65.48μg/m3),with formaldehyde and acetaldehyde contributing over 80%of the total.SOAP exhibited a similar pattern,with values in XH(69.21 to 508.55μg/m3)significantly exceeding those in BJ(34.47 to 159.78μg/m3).The PMF model highlighted vehicle exhaust,secondary pollution,and biomass combustion as major sources of carbonyl compounds,emphasizing differences in source contributions between the two regions.This study’s com-parative analysis over different years and locations provides new insights into the dynamic changes in carbonyl compounds and their environmental importance.These results not only reinforce the importance of carbonyl compounds regulation but also offer a valuable reference for evaluating and refining emission control strategies during this period.展开更多
Paying an additional RMB 2 could have your next milk tea delivered by drone to your balcony in just five minutes.This small fee represents the vast potential of the trillion-yuan lowaltitude economy.
Objectives Glioblastoma multiforme(GBM)is highly resistant to apoptosis.This study investigates the role of Selenoprotein M(SELENOM),a redox-regulating protein,in the response of human glioblastoma A-172 cells to stau...Objectives Glioblastoma multiforme(GBM)is highly resistant to apoptosis.This study investigates the role of Selenoprotein M(SELENOM),a redox-regulating protein,in the response of human glioblastoma A-172 cells to staurosporine(STS)and hyperthermia.Methods A stable SELENOM-knockdown(SELENOM-KD)cell line was created.We measured reactive oxygen species(ROS),mitochondrial membrane potential(ΔΨm),cell death,and apoptotic gene expression.Results SELENOM-KD increased basal ROS levels and induced mitochondrial dysfunction.It sensitized cells to STS-induced apoptosis,enhancing the upregulation of pro-apoptotic genes.Conversely,under hyperthermia(42°C),SELENOM-KD cells exhibited significant thermoresistance,with 52%survival vs.99%death in controls,associated with suppressed pro-apoptotic signaling.Conclusions SELENOM is a critical redox and mitochondrial regulator in GBM.Its loss produces a context-dependent effect on cell fate:sensitizing to chemical apoptosis while conferring resistance to hyperthermia.SELENOM expression is a promising predictive biomarker for stratifying GBM patients for hyperthermia-based therapies.展开更多
Addiction,a complex and chronic neurobiological disorder,is characterized by compulsive substance use despite harmful consequences,leading to persistent alterations in brain function,particularly within the reward,mot...Addiction,a complex and chronic neurobiological disorder,is characterized by compulsive substance use despite harmful consequences,leading to persistent alterations in brain function,particularly within the reward,motivation,and decision-making systems.Despite the availability of a range of treatment options,including pharmacotherapy and behavioral therapies,relapse remains a major challenge,with many individuals struggling to maintain long-term recovery.Current treatments often show limited efficacy,underscoring the need for novel therapeutic strategies that can address the underlying neurobiological disruptions in addiction.展开更多
Eucommia ulmoides is an important economic forest tree species in China,of which the different tissues and organs are widely used in traditional medicine for their abundant bioactive ingredients.Previous studies alway...Eucommia ulmoides is an important economic forest tree species in China,of which the different tissues and organs are widely used in traditional medicine for their abundant bioactive ingredients.Previous studies always focused on the Eucommia gum,a potential alternative to natural rubber because of its“rubber plastic duality”.In recent years,Eucommia has increasingly attracted more attention and interest for its excellent nutritional and economic value,with the deepening of research and the development of products involving in the application of bioactive ingredients.However,the dietary health effects and future application prospects of the bioactive components of E.ulmoides have not been systematically summarized.Therefore,we firstly reviewed the main bioactive ingredients category,structural characteristics,extraction methods and nutritive value.Furthermore,we also summarized the wide application of bioactive ingredients in food and medicine fields.Finally,this review provides a comprehensive overview of the safety and future development of products derived from E.ulmoides,as well as exploring potential applications for its bioactive constituents,aiming to facilitate further extensive investigation into its utilization.展开更多
Lead(Pb)is a typical low-melting-point ductile metal and serves as an important model material in the study of dynamic responses.Under shock-wave loading,its dynamic mechanical behavior comprises two key phenomena:pla...Lead(Pb)is a typical low-melting-point ductile metal and serves as an important model material in the study of dynamic responses.Under shock-wave loading,its dynamic mechanical behavior comprises two key phenomena:plastic deformation and shock-induced phase transitions.The underlying mechanisms of these processes are still poorly understood.Revealing these mechanisms remains challenging for experimental approaches.Non-equilibrium molecular dynamics(NEMD)simulations are an alternative theoretical tool for studying dynamic responses,as they capture atomic-scale mechanisms such as defect evolution and deformation pathways.However,due to the limited accuracy of empirical interatomic potentials,the reliability of previous NEMD studies has been questioned.Using our newly developed machine learning potential for Pb-Sn alloys,we revisited the microstructural evolution in response to shock loading under various shock orientations.The results reveal that shock loading along the[001]orientation of Pb exhibits a fast,reversible,and massive phase transition and stacking-fault evolution.The behavior of Pb differs from previous studies by the absence of twinning during plastic deformation.Loading along the[011]orientation leads to slow,irreversible plastic deformation,and a localized FCC-BCC phase transition in the Pitsch orientation relationship.This study provides crucial theoretical insights into the dynamic mechanical response of Pb,offering a theoretical input for understanding the microstructure-performance relationship under extreme conditions.展开更多
The Rukwa Rift section of the East Africa Rift System presents a type setting for radiogenic helium accumulation in a petroleum free basin.As a prerequisite for accumulation,a considerable high heat flow anomaly is re...The Rukwa Rift section of the East Africa Rift System presents a type setting for radiogenic helium accumulation in a petroleum free basin.As a prerequisite for accumulation,a considerable high heat flow anomaly is required from tectonothermal events to drive the release and circulation of radiogenic helium in the continental crust.Here we apply statistical analysis on geochemical data observed in thermal springs and recorded heat flow to account for crustal helium mass balance for each tectonothermal event in the region.Our results demonstrate anomalously high heat flow~64-99 mW/m^(2) with a consistent trend of helium isotopic ratio and fluid chemistry in the Rukwa Rift.Mass balance calculation show that the whole crustal volume underlying the East Africa Helium Pool(EAHP)has a capability of producing radiogenic helium of about 9.9×10^(6) mol/yr(22×10^(-6) mol 4He/m^(2) yr)while the total radiogenic helium flux ranges between~2.39×10^(6) mol/yr and~2.68×10^(9) mol/yr.The Tanzania Craton contributes largely to radiogenic helium releasing up to 50% of the total capacity in the region.The total ^(4)He emission in the Rukwa Rift Basin is about 4.45×10^(5)-5.01×10^(8) mol/yr which is thus equivalent to 19%-21% of the total production capacity in the region.These results imply that the helium accumulation in the EAHP would have started as early as Paleoproterozoic(2.349 Ga).These results provide a qualitative and quantitative insight to assess both helium and geothermal potentiality in the region.展开更多
We investigated the effects of fly ash(FA)content on the mechanical properties of recycled aggregate concrete(RAC)and its regeneration potential under freeze and thaw(F-T)cycles.The physical properties of second-gener...We investigated the effects of fly ash(FA)content on the mechanical properties of recycled aggregate concrete(RAC)and its regeneration potential under freeze and thaw(F-T)cycles.The physical properties of second-generation recycled concrete aggregates(RCA)were used to analyze the regeneration potential of RAC after F-T cycles.Scanning electron microscopy was used to study the interfacial transition zone microstructure of RAC after F-T cycles.Results showed that adding 20%FA to RAC significantly enhanced its mechanical properties and frost resistance.Before the F-T cycles,the compressive strength of RAC with 20%FA reached 48.3 MPa,exceeding research strength target of 40 MPa.A majority of second-generation RCA with FA had been verified to attain class Ⅲ,which enabled their practical application in non-structural projects such as backfill trenches and road pavement.However,the second-generation RCA with 20%FA can achieve class Ⅱ,making it ideal for 40 MPa structural concrete.展开更多
Neuronal plasticity,the brain's ability to adapt structurally and functionally,is essential for learning,memory,and recovery from injuries.In neurodegenerative diseases such as Alzheimer's disease and Parkinso...Neuronal plasticity,the brain's ability to adapt structurally and functionally,is essential for learning,memory,and recovery from injuries.In neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease,this plasticity is disrupted,leading to cognitive and motor deficits.This review explores the mechanisms of neuronal plasticity and its effect on Alzheimer's disease and Parkinson's disease.Alzheimer's disease features amyloid-beta plaques and tau tangles that impair synaptic function,while Parkinson's disease involves the loss of dopaminergic neurons affecting motor control.Enhancing neuronal plasticity offers therapeutic potential for these diseases.A systematic literature review was conducted using databases such as PubMed,Scopus,and Google Scholar,focusing on studies of neuronal plasticity in Alzheimer's disease and Parkinson's disease.Data synthesis identified key themes such as synaptic mechanisms,neurogenesis,and therapeutic strategies,linking molecular insights to clinical applications.Results highlight that targeting synaptic plasticity mechanisms,such as long-term potentiation and long-term depression,shows promise.Neurotrophic factors,advanced imaging techniques,and molecular tools(e.g.,clustered regularly interspaced short palindromic repeats and optogenetics)are crucial in understanding and enhancing plasticity.Current therapies,including dopamine replacement,deep brain stimulation,and lifestyle interventions,demonstrate the potential to alleviate symptoms and improve outcomes.In conclusion,enhancing neuronal plasticity through targeted therapies holds significant promise for treating neurodegenerative diseases.Future research should integrate multidisciplinary approaches to fully harness the therapeutic potential of neuronal plasticity in Alzheimer's disease and Parkinson's disease.展开更多
Carbon monoxide-from toxicity to therapeutic potential:Carbon monoxide(CO)has long been known as a toxic gas,primarily associated with environmental pollution and poisoning.Its strong affinity for hemoglobin causes th...Carbon monoxide-from toxicity to therapeutic potential:Carbon monoxide(CO)has long been known as a toxic gas,primarily associated with environmental pollution and poisoning.Its strong affinity for hemoglobin causes the formation of carboxyhemoglobin,which reduces oxygen delivery to the tissues and organs and leads to hypoxia.Despite its well-documented toxicity,previous studies have confirmed that CO also acts as a signaling molecule in the body and plays important physiological roles(Motterlini and Otterbein,2010).展开更多
This study presents a multi-physical modeling approach to analyze the dynamics of moisture potential and stress-deformation features near deep desiccation cracks in clayey soils under three consecutive years’climate ...This study presents a multi-physical modeling approach to analyze the dynamics of moisture potential and stress-deformation features near deep desiccation cracks in clayey soils under three consecutive years’climate variability in an arid region.A triple research approach of statistical analysis,analytical framework,and numerical modeling was used to investigate the complex thermo-hydro-mechanical behavior of desiccation-cracked soil,incorporating realistic climatic data of Qom,Iran.The results revealed the interplay between stress,strain,and pore water pressure over time,demonstrating that soil experiences significant swelling and shrinkage due to cyclic wetting and drying.The horizontal stress distribution shows compressive stress concentration at crack tips during wetting,transitioning to tensile stresses uniformly across the soil surface during drying paths.Similarly,vertical stress distributions exhibit localized compressive stresses along crack boundaries during wetting and tensile stresses during drying,highlighting the critical stress conditions at crack tips.The model differentiates between microstructural and macrostructural changes in porosity.Annual trends in micro-porosity revealed cyclic-dependent behavior,with significant volumetric changes occurring in the first year,stabilizing with successive cycles.The results also indicated that part of the volumetric changes are irreversible,with volumetric plastic strain increasing exponentially but at a decreasing rate over three years.Principal stress analysis indicates a shift from compressive to tensile stress states around cracks,driven by climate-induced wetting and drying cycles.These findings underscore the critical role of climate variability in shaping cracked soil behavior in arid regions,providing insights into the heterogeneous behavior of cracked soil surfFicial layers.展开更多
All-solid-state batteries(ASSBs)represent a next-generation energy storage technology,offering enhanced safety,higher energy density,and improved cycling stability compared to conventional liquid-electrolyte-based lit...All-solid-state batteries(ASSBs)represent a next-generation energy storage technology,offering enhanced safety,higher energy density,and improved cycling stability compared to conventional liquid-electrolyte-based lithium-ion batteries.Understanding and optimizing the complex chemistries and interfaces that underpin ASSB performance present significant challenges from both experimental and modeling perspectives.In particular,atomistic simulations face difficulties in capturing the complex structure,disorder,and dynamic evolution of materials and interfaces under practically relevant conditions.While established methods such as density functional theory and classical force fields have provided valuable insights,some questions remain difficult to address,particularly those involving large system sizes or long timescales.Recently,machine learning interatomic potentials(MLIPs)have emerged as a transformative tool,enabling atomistic simulations at length and time scales that were previously challenging to access with conventional approaches.By delivering near first-principles accuracy with much greater efficiency,MLIPs open new avenues for large-scale,long-timescale,and high-throughput simulations of solid-state battery materials.In this review,we present a comparative overview of density functional theory,classical force fields,and MLIPs,highlighting their respective strengths and limitations in ASSB research.We then discuss how MLIPs enable simulations that reach longer timescales,larger system sizes,and support high-throughput calculations,providing unique insights into ion transport and interfacial evolution in ASSBs.Finally,we conclude with a summary and outlook on current challenges and future opportunities for expanding MLIP capabilities and accelerating their impact in solid-state battery research.展开更多
To address low learning efficiency and inadequate path safety in spraying robot navigation within complex obstacle-rich environments—with dense,dynamic,unpredictable obstacles challenging conventional methods—this p...To address low learning efficiency and inadequate path safety in spraying robot navigation within complex obstacle-rich environments—with dense,dynamic,unpredictable obstacles challenging conventional methods—this paper proposes a hybrid algorithm integrating Q-learning and improved A*-Artificial Potential Field(A-APF).Centered on theQ-learning framework,the algorithmleverages safety-oriented guidance generated byA-APF and employs a dynamic coordination mechanism that adaptively balances exploration and exploitation.The proposed system comprises four core modules:(1)an environment modeling module that constructs grid-based obstacle maps;(2)an A-APF module that combines heuristic search from A*algorithm with repulsive force strategies from APF to generate guidance;(3)a Q-learning module that learns optimal state-action values(Q-values)through spraying robot-environment interaction and a reward function emphasizing path optimality and safety;and(4)a dynamic optimization module that ensures adaptive cooperation between Q-learning and A-APF through exploration rate control and environment-aware constraints.Simulation results demonstrate that the proposed method significantly enhances path safety in complex underground mining environments.Quantitative results indicate that,compared to the traditional Q-learning algorithm,the proposed method shortens training time by 42.95% and achieves a reduction in training failures from 78 to just 3.Compared to the static fusion algorithm,it further reduces both training time(by 10.78%)and training failures(by 50%),thereby improving overall training efficiency.展开更多
Improved yield potential is the goal of barley domestication and cultivation.During this process,two-and six-rowed barley types emerged and have been utilised in breeding and production.The six-rowed type could produc...Improved yield potential is the goal of barley domestication and cultivation.During this process,two-and six-rowed barley types emerged and have been utilised in breeding and production.The six-rowed type could produce three times as many grains as its ancestral two-rowed forms,thus dominating barley cultivation for thousands of years.The deficiens form of the two-rowed type,characterised by extremely suppressed lateral spikelets,has gained dominance over the past few decades in barley-growing regions worldwide.We hypothesised that the absence of lateral spikelets in deficiens barley affects spike architecture and spike-related traits,contributing to its superior yield potential of deficiens barley cultivation.Currently,a deficiens barley variety,RGT Planet,is the most popular barley variety in the world.In this study,we used two F_(2) populations derived from crossing RGT Planet with two canonical two-rowed barley and identified the functional allele Vrs1.t1 associated with deficiens morphology.We observed that the Vrs1.t1 allele may contribute to high yield potential by optimising spike architecture through increased spikelet length,grain number,and grain size.Phylogenetic analysis suggests that the deficiens mutation was likely present from the early stages of barley cultivation in the Fertile Crescent and spread to Ethiopia and beyond with agricultural expansion.We conclude that the ancient deficiens allele Vrs1.t1 has been a critical driver for the recent success of modern barley improvement by optimising spike architecture.展开更多
Tinnitus is a concerning condition that affects most adults worldwide,with a prevalence of 6.7%.Theories of tinnitus have explained that an increase in spontaneous neural activity at the level of the thalamus could in...Tinnitus is a concerning condition that affects most adults worldwide,with a prevalence of 6.7%.Theories of tinnitus have explained that an increase in spontaneous neural activity at the level of the thalamus could induce tinnitus.There are no standardized objective tests for tinnitus assessment because of its multifaceted nature.Hence,the current study aimed to explore the effect of Tinnitus on Latency and Amplitude of the Auditory Middle Latency Response in Audiological Attendees.The study recruited 50 individuals(25 normals and 25 individuals with tinnitus)who underwent audiological evaluations like Pure tone audiometry,immittance,pitch and loudness matching,THI and middle latency response.The IHS program was used to record MLR,which was obtained using tone burst stimuli of 500 Hz,1 KHz,2 KHz,and 4 KHz at a rate of 7.1/s with a constant duration of 5 ms,for a total of 1500 sweeps.As a covariate,pure tone thresholds were one of the variabilities that were addressed by ANCOVA.The amplitude of the Pa component varied significantly between the tinnitus and control groups,according to the MLR data and no other components of MLR reached that significance.Furthermore,there was no discernible variation in the latency or amplitude of MLR among any of the other components.The latency of the waveforms increased as the stimulus frequency increased.Karl Pearson correlation coefficient showed no significant correlation between THI scores and any of the outcome measures except for Pa amplitude.As the Pa component of MLR showed maximum changes between controls and individuals with tinnitus,the Pa component could be considered a potential tool for identifying neurophysiological changes related to tinnitus.展开更多
Understanding the complex deformation mechanisms of non-equimolar multi-principal element alloys(MPEAs)requires high-fidelity atomic-scale simulations.This study develops a deep potential(DP)model to enable molecular ...Understanding the complex deformation mechanisms of non-equimolar multi-principal element alloys(MPEAs)requires high-fidelity atomic-scale simulations.This study develops a deep potential(DP)model to enable molecular dynamics simulations of the Ta_(0.4)Ti_(2)Zr(Ta_(0.4))alloy.Monte Carlo simulations using this potential reveal Ta atom precipitation in the Ta_(0.4)alloy.Under uniaxial tensile loading along the[100]direction in the NPT ensemble,the alloy undergoes a remarkable sequence of phase transformations:an initial body-centered cubic(BCC_(1))to face-centered cubic(FCC)transformation,followed by a reverse transformation from FCC to a distinct BCC phase(BCC_(2)),and finally a BCC_(2) to hexagonal close-packed(HCP)transformation.Critically,the reverse FCC to BCC_(2) transformation induces significant volume contraction.We demonstrate that the inversely transformed BCC_(2) phase primarily accommodates compressive stress.Concurrently,the reorientation of BCC_(2) crystals contributes substantially to the observed high strain hardening.These simulations provide atomic-scale insights into the dynamic structural evolution,sequential phase transformations,and stress partitioning during deformation of the Ta_(0.4)alloy.The developed DP model and the revealed mechanisms offer fundamental theoretical guidance for accelerating the design of high-performance MPEAs.展开更多
The paper considers the initial value problem of inhomogeneous fourth-order Schr¨odinger equation with potential in energy space H^(2)(R^(d)).The global well-posedness is obtained in dimensions d≥5 resorting to ...The paper considers the initial value problem of inhomogeneous fourth-order Schr¨odinger equation with potential in energy space H^(2)(R^(d)).The global well-posedness is obtained in dimensions d≥5 resorting to contractive mapping principle,Strichartz estimates,Caffarelli-Kohn-Nirenberg-type inequality and the continuity method.展开更多
Date palm(Phoenix dactylifera L.)seeds,often discarded as by-products during date fruit processing,represent approximately 6-20%of the fruit’s mass depending on cultivar and maturity stage.Although traditionally used...Date palm(Phoenix dactylifera L.)seeds,often discarded as by-products during date fruit processing,represent approximately 6-20%of the fruit’s mass depending on cultivar and maturity stage.Although traditionally used for producing activated charcoal and in environmental remediation,their pharmacological potential remains underexplored.This study aimed to evaluate the chemical composition,biological activity,and potential commercial value of seeds from four widely consumed Saharan cultivars(Assiane,Boufegouss,Aziza,and Majhoul)collected in the Figuig region.Soxhlet extraction was employed to obtain seed extracts,which were subsequently characterized by qualitative and quantitative phytochemical screening.The analyses revealed the presence of polyphenols,flavonoids,terpenoids,steroids,alkaloids,and other secondary metabolites.The Aziza and Boufegouss varieties were particularly rich in flavonoids(82.09-139.61 mg quercetin equivalents/100 g dry matter)and total polyphenols(69.81-1183.96 mg gallic acid equivalents/100 g dry matter).Mineral profiling confirmed the occurrence of essential trace elements,including Zn,Cu,Fe,and Co.To investigate their antidiabetic potential,in vitro assays ofα-glucosidase andα-amylase inhibition were performed.Acetone extracts demonstrated significant inhibitory activity against both enzymes,suggesting a promising role of P.dactylifera seed extracts as natural agents for the management of type 2 diabetes mellitus.展开更多
Oxidative potential(OP)can be used as an indicator of the health risks of particulate matter in the air.To study the variation and sources of OP,we conducted an observation of PM_(2.5) in a megacity in southern China ...Oxidative potential(OP)can be used as an indicator of the health risks of particulate matter in the air.To study the variation and sources of OP,we conducted an observation of PM_(2.5) in a megacity in southern China in winter and spring of 2021.The results show that the average concentration of PM_(2.5) decreased by 47%from winter to spring,while volume-normalized and mass-normalized OP(i.e.,OP_(v) and OP_(m))increased by 6%and 69%,respectively.It suggests that the decline of PM_(2.5) may not necessarily decrease the health risks and the intrinsic toxicity of PM_(2.5).Variations of OP_(v) and OP_(m) among different periods were related to the different source contributions and environmental conditions.The positive matrix factorization model was used to identify the major sources of OP_(v).OP_(v) was mainly contributed by biomass burning/industrial emissions(29%),soil/road dust(20%),secondary sulfate(14%),and coal combustion(13%)in winter.Different major sources were resolved to be secondary sulfate(36%),biological sources(21%),and marine vessels(20%)in spring,presenting the substantial contribution of biological sources.The analysis shows strong associations between OP_(v) and both live and dead bacteria,further confirming the important contribution of bioaerosols to the enhancement of OP.This study highlights the importance of understanding OP in ambient PM_(2.5) in terms of public health impact and provides a new insight into the biological contribution to OP.展开更多
基金National Natural Science Foundation of China(42575091)Marine Meteorological Science and Data Center Program (2024B1212070014)。
文摘In this study, the ground potential rise(GPR) phenomenon caused by a lightning current injected into a field-shaped artificial grounding grid, as well as the potential difference between two different nodes at the edge of the grounding grid, was observed and analyzed under artificially triggered lightning conditions. Based on circuit theory and measured current data, a π-equivalent circuit was established to simulate the transient response of the grounding grid.Nineteen return strokes from three artificially triggered lightning events were analyzed. The peak currents of the 19 return strokes range from -6.7 to -25.1 kA, and the mean value was -14.3 kA. The GPR decreased rapidly and formed a subpeak after reaching the initial peak, with the mean value of the initial peak being -148.65 kV and the mean value of the subpeak being -92.87 kV. The GPR induced by the triggered lightning currents exhibited a subpeak phenomenon. Simulation results indicate that the subpeak phenomenon is related to localized corrosion of the vertical grounding electrode. The potential difference at the grounding grid edge exhibited a multi-pulse waveform with alternating polarity, dominated by positive pulses. The peak values of both the positive and negative polarity pulses gradually decreased, with the first positive pulse displaying a significantly higher intensity than that of subsequent pulses.
基金supported by the National Natural Science Foundation of China(Nos.41905108 and 42130704).
文摘Carbonyl compounds play a pivotal role in the formation of secondary pollutants such as O_(3) and SOA,signifi-cantly impacting air quality and human health.This study extended the observation period compared to previous research,providing a long-term perspective on carbonyl compound variations and their environmental implica-tions.Atmospheric observations were conducted at Beijing(BJ)and Xianghe(XH)during the summer and winter months of 2018,2019,and 2023 to study the sources and impacts of carbonyl compounds in typical urban areas and peri‑urban areas.Notably,concentrations in the summer of 2023 increased compared to 2018 and 2019.The predominant carbonyl compounds—formaldehyde,acetaldehyde,and acetone—accounted for over 60%of the total.The mean values of OFP in BJ ranged from 18.55 to 58.61μg/m3,lower than those in XH(29.82 to 65.48μg/m3),with formaldehyde and acetaldehyde contributing over 80%of the total.SOAP exhibited a similar pattern,with values in XH(69.21 to 508.55μg/m3)significantly exceeding those in BJ(34.47 to 159.78μg/m3).The PMF model highlighted vehicle exhaust,secondary pollution,and biomass combustion as major sources of carbonyl compounds,emphasizing differences in source contributions between the two regions.This study’s com-parative analysis over different years and locations provides new insights into the dynamic changes in carbonyl compounds and their environmental importance.These results not only reinforce the importance of carbonyl compounds regulation but also offer a valuable reference for evaluating and refining emission control strategies during this period.
文摘Paying an additional RMB 2 could have your next milk tea delivered by drone to your balcony in just five minutes.This small fee represents the vast potential of the trillion-yuan lowaltitude economy.
基金the framework of the State assignment No.075-00607-25-00.
文摘Objectives Glioblastoma multiforme(GBM)is highly resistant to apoptosis.This study investigates the role of Selenoprotein M(SELENOM),a redox-regulating protein,in the response of human glioblastoma A-172 cells to staurosporine(STS)and hyperthermia.Methods A stable SELENOM-knockdown(SELENOM-KD)cell line was created.We measured reactive oxygen species(ROS),mitochondrial membrane potential(ΔΨm),cell death,and apoptotic gene expression.Results SELENOM-KD increased basal ROS levels and induced mitochondrial dysfunction.It sensitized cells to STS-induced apoptosis,enhancing the upregulation of pro-apoptotic genes.Conversely,under hyperthermia(42°C),SELENOM-KD cells exhibited significant thermoresistance,with 52%survival vs.99%death in controls,associated with suppressed pro-apoptotic signaling.Conclusions SELENOM is a critical redox and mitochondrial regulator in GBM.Its loss produces a context-dependent effect on cell fate:sensitizing to chemical apoptosis while conferring resistance to hyperthermia.SELENOM expression is a promising predictive biomarker for stratifying GBM patients for hyperthermia-based therapies.
基金supported by the National Natural Science Foundation of China(T2350008)the STI2030-Major Projects[2021ZD0203000(2021ZD0203003)]the Open Research Fund of the State Key Laboratory of Brain-Machine Intelligence,Zhejiang University(BMI2400014).
文摘Addiction,a complex and chronic neurobiological disorder,is characterized by compulsive substance use despite harmful consequences,leading to persistent alterations in brain function,particularly within the reward,motivation,and decision-making systems.Despite the availability of a range of treatment options,including pharmacotherapy and behavioral therapies,relapse remains a major challenge,with many individuals struggling to maintain long-term recovery.Current treatments often show limited efficacy,underscoring the need for novel therapeutic strategies that can address the underlying neurobiological disruptions in addiction.
基金financially supported by the National Natural Science Foundation of China(32201586 and 32301760)Key Specialized Research and Development Program in Henan Province(232102110218)+1 种基金Postdoctoral Research Start-Up Fund of Henan Province(HN2022112)Special Fund for Young Talents in Henan Agricultural University(30501318).
文摘Eucommia ulmoides is an important economic forest tree species in China,of which the different tissues and organs are widely used in traditional medicine for their abundant bioactive ingredients.Previous studies always focused on the Eucommia gum,a potential alternative to natural rubber because of its“rubber plastic duality”.In recent years,Eucommia has increasingly attracted more attention and interest for its excellent nutritional and economic value,with the deepening of research and the development of products involving in the application of bioactive ingredients.However,the dietary health effects and future application prospects of the bioactive components of E.ulmoides have not been systematically summarized.Therefore,we firstly reviewed the main bioactive ingredients category,structural characteristics,extraction methods and nutritive value.Furthermore,we also summarized the wide application of bioactive ingredients in food and medicine fields.Finally,this review provides a comprehensive overview of the safety and future development of products derived from E.ulmoides,as well as exploring potential applications for its bioactive constituents,aiming to facilitate further extensive investigation into its utilization.
基金supported by the National Key R&D Program of China(Grant No.2022YFA1004300)the National Natural Science Foundation of China(Grant No.12404004)。
文摘Lead(Pb)is a typical low-melting-point ductile metal and serves as an important model material in the study of dynamic responses.Under shock-wave loading,its dynamic mechanical behavior comprises two key phenomena:plastic deformation and shock-induced phase transitions.The underlying mechanisms of these processes are still poorly understood.Revealing these mechanisms remains challenging for experimental approaches.Non-equilibrium molecular dynamics(NEMD)simulations are an alternative theoretical tool for studying dynamic responses,as they capture atomic-scale mechanisms such as defect evolution and deformation pathways.However,due to the limited accuracy of empirical interatomic potentials,the reliability of previous NEMD studies has been questioned.Using our newly developed machine learning potential for Pb-Sn alloys,we revisited the microstructural evolution in response to shock loading under various shock orientations.The results reveal that shock loading along the[001]orientation of Pb exhibits a fast,reversible,and massive phase transition and stacking-fault evolution.The behavior of Pb differs from previous studies by the absence of twinning during plastic deformation.Loading along the[011]orientation leads to slow,irreversible plastic deformation,and a localized FCC-BCC phase transition in the Pitsch orientation relationship.This study provides crucial theoretical insights into the dynamic mechanical response of Pb,offering a theoretical input for understanding the microstructure-performance relationship under extreme conditions.
基金funded by United Kingdom Commonwealth Scholarship Commission。
文摘The Rukwa Rift section of the East Africa Rift System presents a type setting for radiogenic helium accumulation in a petroleum free basin.As a prerequisite for accumulation,a considerable high heat flow anomaly is required from tectonothermal events to drive the release and circulation of radiogenic helium in the continental crust.Here we apply statistical analysis on geochemical data observed in thermal springs and recorded heat flow to account for crustal helium mass balance for each tectonothermal event in the region.Our results demonstrate anomalously high heat flow~64-99 mW/m^(2) with a consistent trend of helium isotopic ratio and fluid chemistry in the Rukwa Rift.Mass balance calculation show that the whole crustal volume underlying the East Africa Helium Pool(EAHP)has a capability of producing radiogenic helium of about 9.9×10^(6) mol/yr(22×10^(-6) mol 4He/m^(2) yr)while the total radiogenic helium flux ranges between~2.39×10^(6) mol/yr and~2.68×10^(9) mol/yr.The Tanzania Craton contributes largely to radiogenic helium releasing up to 50% of the total capacity in the region.The total ^(4)He emission in the Rukwa Rift Basin is about 4.45×10^(5)-5.01×10^(8) mol/yr which is thus equivalent to 19%-21% of the total production capacity in the region.These results imply that the helium accumulation in the EAHP would have started as early as Paleoproterozoic(2.349 Ga).These results provide a qualitative and quantitative insight to assess both helium and geothermal potentiality in the region.
基金Funded by the Natural Science Foundation of Jiangsu Province(No.BK20220626)the National Natural Science Foundation of China(No.52078068)+2 种基金Science and Technology Innovation Foundation of NIT(No.KCTD006)Jiangsu Marine Structure Service Performance Improvement Engineering Research CenterKey Laboratory of Jiangsu"Marine Floating Wind Power Technology and Equipment"。
文摘We investigated the effects of fly ash(FA)content on the mechanical properties of recycled aggregate concrete(RAC)and its regeneration potential under freeze and thaw(F-T)cycles.The physical properties of second-generation recycled concrete aggregates(RCA)were used to analyze the regeneration potential of RAC after F-T cycles.Scanning electron microscopy was used to study the interfacial transition zone microstructure of RAC after F-T cycles.Results showed that adding 20%FA to RAC significantly enhanced its mechanical properties and frost resistance.Before the F-T cycles,the compressive strength of RAC with 20%FA reached 48.3 MPa,exceeding research strength target of 40 MPa.A majority of second-generation RCA with FA had been verified to attain class Ⅲ,which enabled their practical application in non-structural projects such as backfill trenches and road pavement.However,the second-generation RCA with 20%FA can achieve class Ⅱ,making it ideal for 40 MPa structural concrete.
基金financially supported by King Abdulaziz University,Deanship of Scientific Research(DSR)。
文摘Neuronal plasticity,the brain's ability to adapt structurally and functionally,is essential for learning,memory,and recovery from injuries.In neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease,this plasticity is disrupted,leading to cognitive and motor deficits.This review explores the mechanisms of neuronal plasticity and its effect on Alzheimer's disease and Parkinson's disease.Alzheimer's disease features amyloid-beta plaques and tau tangles that impair synaptic function,while Parkinson's disease involves the loss of dopaminergic neurons affecting motor control.Enhancing neuronal plasticity offers therapeutic potential for these diseases.A systematic literature review was conducted using databases such as PubMed,Scopus,and Google Scholar,focusing on studies of neuronal plasticity in Alzheimer's disease and Parkinson's disease.Data synthesis identified key themes such as synaptic mechanisms,neurogenesis,and therapeutic strategies,linking molecular insights to clinical applications.Results highlight that targeting synaptic plasticity mechanisms,such as long-term potentiation and long-term depression,shows promise.Neurotrophic factors,advanced imaging techniques,and molecular tools(e.g.,clustered regularly interspaced short palindromic repeats and optogenetics)are crucial in understanding and enhancing plasticity.Current therapies,including dopamine replacement,deep brain stimulation,and lifestyle interventions,demonstrate the potential to alleviate symptoms and improve outcomes.In conclusion,enhancing neuronal plasticity through targeted therapies holds significant promise for treating neurodegenerative diseases.Future research should integrate multidisciplinary approaches to fully harness the therapeutic potential of neuronal plasticity in Alzheimer's disease and Parkinson's disease.
基金supported in part by the NIH(R01NS113556,to KA).
文摘Carbon monoxide-from toxicity to therapeutic potential:Carbon monoxide(CO)has long been known as a toxic gas,primarily associated with environmental pollution and poisoning.Its strong affinity for hemoglobin causes the formation of carboxyhemoglobin,which reduces oxygen delivery to the tissues and organs and leads to hypoxia.Despite its well-documented toxicity,previous studies have confirmed that CO also acts as a signaling molecule in the body and plays important physiological roles(Motterlini and Otterbein,2010).
基金support provided by the Research Grant Office at Sharif University Technology by way of grants G4010902 and QB020105 is gratefully acknowledged.
文摘This study presents a multi-physical modeling approach to analyze the dynamics of moisture potential and stress-deformation features near deep desiccation cracks in clayey soils under three consecutive years’climate variability in an arid region.A triple research approach of statistical analysis,analytical framework,and numerical modeling was used to investigate the complex thermo-hydro-mechanical behavior of desiccation-cracked soil,incorporating realistic climatic data of Qom,Iran.The results revealed the interplay between stress,strain,and pore water pressure over time,demonstrating that soil experiences significant swelling and shrinkage due to cyclic wetting and drying.The horizontal stress distribution shows compressive stress concentration at crack tips during wetting,transitioning to tensile stresses uniformly across the soil surface during drying paths.Similarly,vertical stress distributions exhibit localized compressive stresses along crack boundaries during wetting and tensile stresses during drying,highlighting the critical stress conditions at crack tips.The model differentiates between microstructural and macrostructural changes in porosity.Annual trends in micro-porosity revealed cyclic-dependent behavior,with significant volumetric changes occurring in the first year,stabilizing with successive cycles.The results also indicated that part of the volumetric changes are irreversible,with volumetric plastic strain increasing exponentially but at a decreasing rate over three years.Principal stress analysis indicates a shift from compressive to tensile stress states around cracks,driven by climate-induced wetting and drying cycles.These findings underscore the critical role of climate variability in shaping cracked soil behavior in arid regions,providing insights into the heterogeneous behavior of cracked soil surfFicial layers.
文摘All-solid-state batteries(ASSBs)represent a next-generation energy storage technology,offering enhanced safety,higher energy density,and improved cycling stability compared to conventional liquid-electrolyte-based lithium-ion batteries.Understanding and optimizing the complex chemistries and interfaces that underpin ASSB performance present significant challenges from both experimental and modeling perspectives.In particular,atomistic simulations face difficulties in capturing the complex structure,disorder,and dynamic evolution of materials and interfaces under practically relevant conditions.While established methods such as density functional theory and classical force fields have provided valuable insights,some questions remain difficult to address,particularly those involving large system sizes or long timescales.Recently,machine learning interatomic potentials(MLIPs)have emerged as a transformative tool,enabling atomistic simulations at length and time scales that were previously challenging to access with conventional approaches.By delivering near first-principles accuracy with much greater efficiency,MLIPs open new avenues for large-scale,long-timescale,and high-throughput simulations of solid-state battery materials.In this review,we present a comparative overview of density functional theory,classical force fields,and MLIPs,highlighting their respective strengths and limitations in ASSB research.We then discuss how MLIPs enable simulations that reach longer timescales,larger system sizes,and support high-throughput calculations,providing unique insights into ion transport and interfacial evolution in ASSBs.Finally,we conclude with a summary and outlook on current challenges and future opportunities for expanding MLIP capabilities and accelerating their impact in solid-state battery research.
基金supported by the National Natural Science Foundation of China(Grant No.52374156).
文摘To address low learning efficiency and inadequate path safety in spraying robot navigation within complex obstacle-rich environments—with dense,dynamic,unpredictable obstacles challenging conventional methods—this paper proposes a hybrid algorithm integrating Q-learning and improved A*-Artificial Potential Field(A-APF).Centered on theQ-learning framework,the algorithmleverages safety-oriented guidance generated byA-APF and employs a dynamic coordination mechanism that adaptively balances exploration and exploitation.The proposed system comprises four core modules:(1)an environment modeling module that constructs grid-based obstacle maps;(2)an A-APF module that combines heuristic search from A*algorithm with repulsive force strategies from APF to generate guidance;(3)a Q-learning module that learns optimal state-action values(Q-values)through spraying robot-environment interaction and a reward function emphasizing path optimality and safety;and(4)a dynamic optimization module that ensures adaptive cooperation between Q-learning and A-APF through exploration rate control and environment-aware constraints.Simulation results demonstrate that the proposed method significantly enhances path safety in complex underground mining environments.Quantitative results indicate that,compared to the traditional Q-learning algorithm,the proposed method shortens training time by 42.95% and achieves a reduction in training failures from 78 to just 3.Compared to the static fusion algorithm,it further reduces both training time(by 10.78%)and training failures(by 50%),thereby improving overall training efficiency.
基金Funding for this research was provided by the Australia Grain Research and Development Corporation(9176507)the Western Crop Genetics Alliance.Jingye Cheng thanks The University of Tasmania,Australia for the scholarship(495802)。
文摘Improved yield potential is the goal of barley domestication and cultivation.During this process,two-and six-rowed barley types emerged and have been utilised in breeding and production.The six-rowed type could produce three times as many grains as its ancestral two-rowed forms,thus dominating barley cultivation for thousands of years.The deficiens form of the two-rowed type,characterised by extremely suppressed lateral spikelets,has gained dominance over the past few decades in barley-growing regions worldwide.We hypothesised that the absence of lateral spikelets in deficiens barley affects spike architecture and spike-related traits,contributing to its superior yield potential of deficiens barley cultivation.Currently,a deficiens barley variety,RGT Planet,is the most popular barley variety in the world.In this study,we used two F_(2) populations derived from crossing RGT Planet with two canonical two-rowed barley and identified the functional allele Vrs1.t1 associated with deficiens morphology.We observed that the Vrs1.t1 allele may contribute to high yield potential by optimising spike architecture through increased spikelet length,grain number,and grain size.Phylogenetic analysis suggests that the deficiens mutation was likely present from the early stages of barley cultivation in the Fertile Crescent and spread to Ethiopia and beyond with agricultural expansion.We conclude that the ancient deficiens allele Vrs1.t1 has been a critical driver for the recent success of modern barley improvement by optimising spike architecture.
文摘Tinnitus is a concerning condition that affects most adults worldwide,with a prevalence of 6.7%.Theories of tinnitus have explained that an increase in spontaneous neural activity at the level of the thalamus could induce tinnitus.There are no standardized objective tests for tinnitus assessment because of its multifaceted nature.Hence,the current study aimed to explore the effect of Tinnitus on Latency and Amplitude of the Auditory Middle Latency Response in Audiological Attendees.The study recruited 50 individuals(25 normals and 25 individuals with tinnitus)who underwent audiological evaluations like Pure tone audiometry,immittance,pitch and loudness matching,THI and middle latency response.The IHS program was used to record MLR,which was obtained using tone burst stimuli of 500 Hz,1 KHz,2 KHz,and 4 KHz at a rate of 7.1/s with a constant duration of 5 ms,for a total of 1500 sweeps.As a covariate,pure tone thresholds were one of the variabilities that were addressed by ANCOVA.The amplitude of the Pa component varied significantly between the tinnitus and control groups,according to the MLR data and no other components of MLR reached that significance.Furthermore,there was no discernible variation in the latency or amplitude of MLR among any of the other components.The latency of the waveforms increased as the stimulus frequency increased.Karl Pearson correlation coefficient showed no significant correlation between THI scores and any of the outcome measures except for Pa amplitude.As the Pa component of MLR showed maximum changes between controls and individuals with tinnitus,the Pa component could be considered a potential tool for identifying neurophysiological changes related to tinnitus.
基金supported by the National University of Defense Technology Research Fund Projectthe National Natural Science Foundation of China(Grant No.12534013)the Science and Technology Innovation Program of Hunan Province(Grant Nos.2025ZYJ001 and 2021RC4026)。
文摘Understanding the complex deformation mechanisms of non-equimolar multi-principal element alloys(MPEAs)requires high-fidelity atomic-scale simulations.This study develops a deep potential(DP)model to enable molecular dynamics simulations of the Ta_(0.4)Ti_(2)Zr(Ta_(0.4))alloy.Monte Carlo simulations using this potential reveal Ta atom precipitation in the Ta_(0.4)alloy.Under uniaxial tensile loading along the[100]direction in the NPT ensemble,the alloy undergoes a remarkable sequence of phase transformations:an initial body-centered cubic(BCC_(1))to face-centered cubic(FCC)transformation,followed by a reverse transformation from FCC to a distinct BCC phase(BCC_(2)),and finally a BCC_(2) to hexagonal close-packed(HCP)transformation.Critically,the reverse FCC to BCC_(2) transformation induces significant volume contraction.We demonstrate that the inversely transformed BCC_(2) phase primarily accommodates compressive stress.Concurrently,the reorientation of BCC_(2) crystals contributes substantially to the observed high strain hardening.These simulations provide atomic-scale insights into the dynamic structural evolution,sequential phase transformations,and stress partitioning during deformation of the Ta_(0.4)alloy.The developed DP model and the revealed mechanisms offer fundamental theoretical guidance for accelerating the design of high-performance MPEAs.
基金Supported by National Natural Science Foundation of China(Grant No.11601122).
文摘The paper considers the initial value problem of inhomogeneous fourth-order Schr¨odinger equation with potential in energy space H^(2)(R^(d)).The global well-posedness is obtained in dimensions d≥5 resorting to contractive mapping principle,Strichartz estimates,Caffarelli-Kohn-Nirenberg-type inequality and the continuity method.
文摘Date palm(Phoenix dactylifera L.)seeds,often discarded as by-products during date fruit processing,represent approximately 6-20%of the fruit’s mass depending on cultivar and maturity stage.Although traditionally used for producing activated charcoal and in environmental remediation,their pharmacological potential remains underexplored.This study aimed to evaluate the chemical composition,biological activity,and potential commercial value of seeds from four widely consumed Saharan cultivars(Assiane,Boufegouss,Aziza,and Majhoul)collected in the Figuig region.Soxhlet extraction was employed to obtain seed extracts,which were subsequently characterized by qualitative and quantitative phytochemical screening.The analyses revealed the presence of polyphenols,flavonoids,terpenoids,steroids,alkaloids,and other secondary metabolites.The Aziza and Boufegouss varieties were particularly rich in flavonoids(82.09-139.61 mg quercetin equivalents/100 g dry matter)and total polyphenols(69.81-1183.96 mg gallic acid equivalents/100 g dry matter).Mineral profiling confirmed the occurrence of essential trace elements,including Zn,Cu,Fe,and Co.To investigate their antidiabetic potential,in vitro assays ofα-glucosidase andα-amylase inhibition were performed.Acetone extracts demonstrated significant inhibitory activity against both enzymes,suggesting a promising role of P.dactylifera seed extracts as natural agents for the management of type 2 diabetes mellitus.
基金supported by the National Natural Science Foundation of China(No.41975156)and the Fundamental Research Funds for the Central Universities.
文摘Oxidative potential(OP)can be used as an indicator of the health risks of particulate matter in the air.To study the variation and sources of OP,we conducted an observation of PM_(2.5) in a megacity in southern China in winter and spring of 2021.The results show that the average concentration of PM_(2.5) decreased by 47%from winter to spring,while volume-normalized and mass-normalized OP(i.e.,OP_(v) and OP_(m))increased by 6%and 69%,respectively.It suggests that the decline of PM_(2.5) may not necessarily decrease the health risks and the intrinsic toxicity of PM_(2.5).Variations of OP_(v) and OP_(m) among different periods were related to the different source contributions and environmental conditions.The positive matrix factorization model was used to identify the major sources of OP_(v).OP_(v) was mainly contributed by biomass burning/industrial emissions(29%),soil/road dust(20%),secondary sulfate(14%),and coal combustion(13%)in winter.Different major sources were resolved to be secondary sulfate(36%),biological sources(21%),and marine vessels(20%)in spring,presenting the substantial contribution of biological sources.The analysis shows strong associations between OP_(v) and both live and dead bacteria,further confirming the important contribution of bioaerosols to the enhancement of OP.This study highlights the importance of understanding OP in ambient PM_(2.5) in terms of public health impact and provides a new insight into the biological contribution to OP.