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Latent Profile Analysis:Mattering Concepts,Problematic Internet Use,and Adaptability in Chinese University Students
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作者 Jianlong Wang Xiumei Chen +3 位作者 Muqi Huang Rui Liu I-Hua Chen Gordon L.Flett 《International Journal of Mental Health Promotion》 2025年第2期241-256,共16页
Background:This study addresses the pressing need to understand the nuanced relationship between‘mattering’—the perception of being significant to others—and problematic internet use(PIU)among university students.... Background:This study addresses the pressing need to understand the nuanced relationship between‘mattering’—the perception of being significant to others—and problematic internet use(PIU)among university students.Unlike previous research that has primarily employed variable-centered approaches,this study first adopts a person-centered approach using Latent Profile Analysis(LPA)to identify distinct mattering profiles.Subsequently,through variable-centered analyses,these profiles are examined in relation to different types of PIU—specifically problematic social media use(PSMU)and problematic gaming(PG)—as well as adaptability.Methods:Data were collected from 3587 university students across 19 universities in China.Participants completed three mattering-related scales(General Mattering Scale,Anti-Mattering Scale,and Fear of Not Mattering Inventory),along with the Bergen Social Media Addiction Scale,the Internet Gaming Disorder Scale-Short Form,and the Nine-item Adaptability Scale.Results:A four-class model identified by LPA was optimally selected:Class 1(high general mattering,low anti-mattering,low fear of not mattering),Class 2(moderate levels),Class 3(moderate general mattering,high antimattering,high fear of not mattering),and Class 4(low general mattering,low fear of not mattering,moderate anti-mattering).Significant differences were found among these classes in both PIU types(PSMU:F=139.66,p<0.001;PG:F=162.96,p<0.001).The pattern of mean differences consistently showed:Class 3>Class 2>Class 4>Class 1.Class 3 participants demonstrated the highest likelihood of meeting the addiction criteria,Class 2 showed moderate probability,while Classes 1 and 4 exhibited lower probabilities(χ^(2)=113.38 to 408.87,all p<0.001).Additionally,Class 3 reported the lowest adaptability(F=131.67,p<0.001).Conclusion:This study reveals that the unique influence of three ways of assessing feelings of mattering and the fear of not mattering on university students’PIU at the personal level,concluding that these factors are integral to understanding PIU among this demographic. 展开更多
关键词 mattering problematic social media use problematic gaming ADAPTABILITY latent profile analysis
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The pivotal role of microglia in injury and the prognosis of subarachnoid hemorrhage 被引量:2
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作者 Wenjing Ning Shi Lv +1 位作者 Qian Wang Yuzhen Xu 《Neural Regeneration Research》 SCIE CAS 2025年第7期1829-1848,共20页
Subarachnoid hemorrhage leads to a series of pathological changes,including vascular spasm,cellular apoptosis,blood–brain barrier damage,cerebral edema,and white matter injury.Microglia,which are the key immune cells... Subarachnoid hemorrhage leads to a series of pathological changes,including vascular spasm,cellular apoptosis,blood–brain barrier damage,cerebral edema,and white matter injury.Microglia,which are the key immune cells in the central nervous system,maintain homeostasis in the neural environment,support neurons,mediate apoptosis,participate in immune regulation,and have neuroprotective effects.Increasing evidence has shown that microglia play a pivotal role in the pathogenesis of subarachnoid hemorrhage and affect the process of injury and the prognosis of subarachnoid hemorrhage.Moreover,microglia play certain neuroprotective roles in the recovery phase of subarachnoid hemorrhage.Several approaches aimed at modulating microglia function are believed to attenuate subarachnoid hemorrhage injury.This provides new targets and ideas for the treatment of subarachnoid hemorrhage.However,an in-depth and comprehensive summary of the role of microglia after subarachnoid hemorrhage is still lacking.This review describes the activation of microglia after subarachnoid hemorrhage and their roles in the pathological processes of vasospasm,neuroinflammation,neuronal apoptosis,blood–brain barrier disruption,cerebral edema,and cerebral white matter lesions.It also discusses the neuroprotective roles of microglia during recovery from subarachnoid hemorrhage and therapeutic advances aimed at modulating microglial function after subarachnoid hemorrhage.Currently,microglia in subarachnoid hemorrhage are targeted with TLR inhibitors,nuclear factor-κB and STAT3 pathway inhibitors,glycine/tyrosine kinases,NLRP3 signaling pathway inhibitors,Gasdermin D inhibitors,vincristine receptorαreceptor agonists,ferroptosis inhibitors,genetic modification techniques,stem cell therapies,and traditional Chinese medicine.However,most of these are still being evaluated at the laboratory stage.More clinical studies and data on subarachnoid hemorrhage are required to improve the treatment of subarachnoid hemorrhage. 展开更多
关键词 apoptosis blood–brain barrier brain edema MICROGLIA NEUROINFLAMMATION neuron NEUROPROTECTION subarachnoid hemorrhage VASOCONSTRICTION white matter injury
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Humic-like components in dissolved organic matter inhibit cadmium sequestration by sediment 被引量:3
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作者 Bolin Li Zhongwu Li +3 位作者 Jia Chen Changsheng Jin Weicheng Cao Bo Peng 《Journal of Environmental Sciences》 2025年第4期645-656,共12页
China’s lakes are plagued by cadmium(Cd)pollution.Dissolved organic matter(DOM)significantly regulates Cd(II)transport properties at the sediment-water interface.Understanding the effects of different DOM components ... China’s lakes are plagued by cadmium(Cd)pollution.Dissolved organic matter(DOM)significantly regulates Cd(II)transport properties at the sediment-water interface.Understanding the effects of different DOM components on the transportation properties of Cd(II)at the sediment-water interface is essential.In this study,typical DOM from different sources was selected to study Cd(II)mobility at the sediment-water interface.Results showed that terrestrial-derived DOM(fulvic acids,FA)and autochthonous-derived DOM(α-amylase,B1)inhibit Cd(II)sequestration by sediments(42.5%and 5.8%,respectively),while anthropogenic-derived DOM(sodium dodecyl benzene sulfonate,SDBS)increased the Cd(II)adsorption capacity by sediments by 2.8%.Fluorescence quenching coupling with parallel factor analysis(EEM-PARAFAC)was used to characterize different DOM components.The results showed that FA contains three kinds of components(C1,C3:protein-like components,C2:humic-like components);SDBS contains two kinds of components(C1,C2:protein-like components);B1 contains three kinds of components(C1,C2:protein-like components,C3:humic-like components).Three complex reaction modelswere used to characterize the ability of Cd(II)complex with DOM,and it was found that the humic-like component could hardly be complex with Cd(II).Accordingly,humic-like components compete for Cd(II)adsorption sites on the sediment surface and inhibit Cd(II)adsorption fromsediments.Fourier transform infrared spectroscopy(FTIR)of the sediment surface before and after Cd(II)addition was analyzed and proved the competitive adsorption theory.This study provides a better understanding of the Cd(II)mobilization behavior at the sediment-water interface and indicates that the input of humic-like DOM will increase the bioavailability of Cd. 展开更多
关键词 Dissolved organic matter Cadmium Sediments EEM-PARAFAC Adsorption
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Role of Ochrobactrum Bacteria and Organic Matter in Plant Growth and the Content of N,P,and K Under Soil Salinity Stress 被引量:2
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作者 Huda Krebit Hundi Mustafa Qais Hamid Ali Abdul Majeed Noori 《Journal of Environmental & Earth Sciences》 2025年第5期130-139,共10页
Organic matter increases biological activity within the root zone because it contains beneficial microbes that stimulate vital processes.This study aimed to determine the effect of Ochrobactrum anthropi added to the s... Organic matter increases biological activity within the root zone because it contains beneficial microbes that stimulate vital processes.This study aimed to determine the effect of Ochrobactrum anthropi added to the soil as a single or mixed solution with different concentrations of organic matter on the vegetative growth of the zinnia plant and its content of nutrients.The study was conducted with a randomized complete block design(RCBD)with three replications.The plant was grown in soil with a high salinity level of 8 ds m^(–1).Plant characteristics were estimated 30 and 60 days after planting the plant.The treatment with the addition of bio-inoculum produced the best results;within 30 days,there was a 56.89%increase in plant length;after 60 days,there was a 52.56%increase;additionally,there was a 52.56%increase in leaf count within 30 days;after 60 days,there was a 53.50%increase;and finally,there was an increase in flower count.For plants after 60 days,it reached 3.66%.With the addition of bio-inoculum to soil at a level of 3 gm kg^(–1)of organic matter,the mixing treatment achieved the highest dry weight,29.86%.The addition of bio-inoculum resulted in the largest and most significant increase in chlorophyll content in leaves,reaching 18.76%.In the mixing addition of the biological inoculum treatment,the organic content of the plant showed an increase in nitrogen(14.38%),phosphorus(21.18%),and potassium(39.75%)at 2 and 3 gm kg^(–1)organic matter,respectively. 展开更多
关键词 Ochrobactrum anthropi Organic Matter Salt Stress Zinnia elegans
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Rapid reduction of air pollution and short-term exposure risks in China 被引量:1
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作者 Hao Fan Chuanfeng Zhao +1 位作者 Yikun Yang Xingchuan Yang 《Journal of Environmental Sciences》 2025年第3期126-138,共13页
With the continuous control of anthropogenic emissions,China’s air quality has improved significantly in recent years.Given this background,research on how the short-term exposure risks caused by air pollution in Chi... With the continuous control of anthropogenic emissions,China’s air quality has improved significantly in recent years.Given this background,research on how the short-term exposure risks caused by air pollution in China have changed is insufficient.This study utilized hourly concentration data from ground observation stations and the official air quality guidelines of the Ministry of Ecology and Environment of China and the World Health Organization as standards to systematically investigate the spatiotemporal characteristics and short-term exposure risks of air pollution in China from 2015 to 2022.The results indicate that various atmospheric pollutants except for ozone showed a decreasing trend yearly.Nationwide,both single pollutant air pollution days(SAPDs)and multiple pollutant air pollution days(MAPDs)showed varying degrees of reduction within 15 and 25 days,respectively.SAPD was dominated mainly by excessive PM_(2.5)and PM_(10)pollutants,while MAPD was dominated mainly by excessive pollutant combinations,including PM_(2.5)+PM_(10),CO+PM_(2.5)+PM_(10),and SO_(2)+PM_(2.5)+PM_(10).As the concentration of atmospheric pollutants decreased,the total excess risk(ER)decreased yearly from 2015 to 2022,but there were significant regional differences.Now,the ER is less than 0.25%in southern China,in the range of 0.25%-0.5%in the North China Plain and some cities in the northeast,and higher than 1%in the northwest.Particulate matter is currently the primary pollutant posing short-term exposure risk in China,especially due to the impact of sandstorm weather.This study indicates that China’s atmospheric cleaning action is significantly beneficial for reducing health risks. 展开更多
关键词 Air pollution Emission-reduction Total excess risk Particulate matter China
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Exploring the diversity of dissolved organic matter(DOM)properties and sources in different functional areas of a typical macrophyte-derived lake combined with optical spectroscopy and FT-ICR MS analysis 被引量:1
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作者 Kun Wang Haoyu Ren +2 位作者 Shengwu Yuan Xia Jiang Pengfei Wang 《Journal of Environmental Sciences》 2025年第1期462-473,共12页
Lake Baiyangdian is one of China’s largest macrophyte-derived lakes,facing severe challenges related to water quality maintenance and eutrophication prevention.Dissolved organic matter(DOM)was a huge carbon pool and ... Lake Baiyangdian is one of China’s largest macrophyte-derived lakes,facing severe challenges related to water quality maintenance and eutrophication prevention.Dissolved organic matter(DOM)was a huge carbon pool and its abundance,property,and transformation played important roles in the biogeochemical cycle and energy flow in lake ecosystems.In this study,Lake Baiyangdian was divided into four distinct areas:Unartificial Area(UA),Village Area(VA),Tourism Area(TA),and Breeding Area(BA).We examined the diversity of DOM properties and sources across these functional areas.Our findings reveal that DOM in this lake is predominantly composed of protein-like substances,as determined by excitation-emission matrix and parallel factor analysis(EEM-PARAFAC).Notably,the exogenous tyrosine-like component C1 showed a stronger presence in VA and BA compared to UA and TA.Ultrahigh-resolution mass spectrometry(FT-ICR MS)unveiled a similar DOM molecular composition pattern across different functional areas due to the high relative abundances of lignan compounds,suggesting that macrophytes significantly influence the material structure of DOM.DOM properties exhibited specific associations with water quality indicators in various functional areas,as indicated by the Mantel test.The connections between DOM properties and NO_(3)-N andNH3-Nwere more pronounced in VA and BA than in UA and TA.Our results underscore the viability of using DOM as an indicator for more precise and scientific water quality management. 展开更多
关键词 Dissolved organic matter Fluorescence property Molecular composition Source
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Characteristics and phytotoxicity of hydrochar-derived dissolved organic matter:Effects of feedstock type and hydrothermal temperature 被引量:1
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作者 Qianqian Lang Xuan Guo +8 位作者 Chao Wang Lingyao Li Yufei Li Junxiang Xu Xiang Zhao Jijin Li Bensheng Liu Qinping Sun Guoyuan Zou 《Journal of Environmental Sciences》 2025年第3期139-148,共10页
The dissolved organic matter(DOM)with high mobility and reactivity plays a crucial role in soil.In this study,the characteristics and phytotoxicity ofDOMreleased fromthe hydrochars prepared from different feedstocks(c... The dissolved organic matter(DOM)with high mobility and reactivity plays a crucial role in soil.In this study,the characteristics and phytotoxicity ofDOMreleased fromthe hydrochars prepared from different feedstocks(cowmanure,corn stalk and Myriophyllum aquaticum)under three hydrothermal carbonization(HTC)temperatures(180,200 and 220°C)were evaluated.The results showed that the hydrochars had high dissolved organic carbon content(20.15 to 37.65 mg/g)and its content showed a gradual reduction as HTC temperature increased.Three fluorescent components including mixed substance of fulvic acid-like and humic acid-like substances(C1,30.92%-58.32%),UVA humic acid-like substance(C2,25.27%-29.94%)and protein-like substance(C3,11.74%-41.92%)were identified in hydrochar DOM by excitation emission matrix spectra coupled with parallel factor analysis.High HTC temperature increased the relative proportion of aromatic substances(C1+C2)and humification degree of hydrochar DOM from cow manure,while it presented adverse effects on the hydrochar DOM from corn stalk and Myriophyllum.aquaticum.The principal component analysis suggested that feedstock type and HTC temperature posed significant effects on the characteristics of hydrochar DOM.Additionally,seed germination test of all hydrochar DOM demonstrated that the root length was reduced by 8.88%-26.43%in contrast with control,and the germination index values were 73.57%-91.12%.These findings provided new insights into the potential environmental effects for hydrochar application in soil. 展开更多
关键词 Hydrochar Hydrothermal temperature Dissolved organic matter Excitation emission matrix Parallel factor analysis PHYTOTOXICITY
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A study on the impact of liquid metal droplets onto metal and elastomer substrates 被引量:1
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作者 Zilu He Rui Xiao Shaoxing Qu 《Acta Mechanica Sinica》 2025年第4期1-10,共10页
The diffusion and dynamic behaviors of liquid metal droplet during impact significantly affect its application in 3D printing and painting processes.To obtain a better understanding of the impact process of liquid met... The diffusion and dynamic behaviors of liquid metal droplet during impact significantly affect its application in 3D printing and painting processes.To obtain a better understanding of the impact process of liquid metal droplets,we analyze the influence of different initial conditions and substrate materials on droplet spreading,impact force,and elastic wave propagation on the substrate.It is found that an agglomeration phenomenon can be observed when the liquid metal droplets impact onto a soft elastomer substrate,which is not observed as a metal substrate is employed.Regardless of the substrate material,when surface tension dominates the diffusion,the diffusion factor of droplets is proportional to We(Weber number).It is also observed that the self-similarity of liquid metal droplet impact force on copper substrates,which is not the case for soft elastomer substrates.Using smoothed particle hydrodynamics(SPH)simulations,the time-domain curve and peak point of the droplet can be well predicted for a metal substrate.Furthermore,by recording the acceleration signal on the substrates,we further obtain the energy radiated by elastic waves,providing an explanation for energy conversion during the impact process with varying parameters.The results provide an additional understanding on the complex impact behaviors of liquid metal droplets. 展开更多
关键词 Liquid metal Mechanics of soft matter IMPACT
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Fetal Gray Matter Heterotopia 被引量:1
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作者 Jiaojiao Liu Lianxiang Xiao 《iRADIOLOGY》 2025年第3期231-233,共3页
A pregnant woman underwent fetal brain magnetic resonance imaging(MRI)following ultrasound detection of a posterior fossa cyst at 29 weeks'gestation.She presented with no relevant medical history and underwent a r... A pregnant woman underwent fetal brain magnetic resonance imaging(MRI)following ultrasound detection of a posterior fossa cyst at 29 weeks'gestation.She presented with no relevant medical history and underwent a routine obstetric examination during pregnancy.The fetal head position,fetal cranial development,and limb development remained normal until 29 weeks. 展开更多
关键词 fetal magnetic resonance imaging FETUS gray matter heterotopia
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NLRP3 inflammasome and gut microbiota–brain axis:A new perspective on white matter injury after intracerebral hemorrhage 被引量:1
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作者 Xiaoxi Cai Xinhong Cai +4 位作者 Quanhua Xie Xueqi Xiao Tong Li Tian Zhou Haitao Sun 《Neural Regeneration Research》 2026年第1期62-80,共19页
Intracerebral hemorrhage is the most dangerous subtype of stroke,characterized by high mortality and morbidity rates,and frequently leads to significant secondary white matter injury.In recent decades,studies have rev... Intracerebral hemorrhage is the most dangerous subtype of stroke,characterized by high mortality and morbidity rates,and frequently leads to significant secondary white matter injury.In recent decades,studies have revealed that gut microbiota can communicate bidirectionally with the brain through the gut microbiota–brain axis.This axis indicates that gut microbiota is closely related to the development and prognosis of intracerebral hemorrhage and its associated secondary white matter injury.The NACHT,LRR,and pyrin domain-containing protein 3(NLRP3)inflammasome plays a crucial role in this context.This review summarizes the dysbiosis of gut microbiota following intracerebral hemorrhage and explores the mechanisms by which this imbalance may promote the activation of the NLRP3 inflammasome.These mechanisms include metabolic pathways(involving short-chain fatty acids,lipopolysaccharides,lactic acid,bile acids,trimethylamine-N-oxide,and tryptophan),neural pathways(such as the vagus nerve and sympathetic nerve),and immune pathways(involving microglia and T cells).We then discuss the relationship between the activated NLRP3 inflammasome and secondary white matter injury after intracerebral hemorrhage.The activation of the NLRP3 inflammasome can exacerbate secondary white matter injury by disrupting the blood–brain barrier,inducing neuroinflammation,and interfering with nerve regeneration.Finally,we outline potential treatment strategies for intracerebral hemorrhage and its secondary white matter injury.Our review highlights the critical role of the gut microbiota–brain axis and the NLRP3 inflammasome in white matter injury following intracerebral hemorrhage,paving the way for exploring potential therapeutic approaches. 展开更多
关键词 gut microbiota gut microbiota–brain axis immune intracerebral hemorrhage NEUROINFLAMMATION NLRP3 protein stroke THERAPEUTICS white matter injury
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Hydrothermal temperature-dependent compositions and copper complexing behaviors of hydrochar-derived dissolved organic matter: Insights from FT-ICR MS and multi-spectroscopic analysis 被引量:1
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作者 Bingfa Chen Xincai Gu +6 位作者 Muhua Feng Yanfang Feng Bingyu Wang Bensheng You Jingcheng Zheng Hong Liu Shiqun Han 《Journal of Environmental Sciences》 2025年第6期685-700,共16页
The copper complexing of dissolved organic matter released from hydrochar(HDOM)affects the former’s environmental behavior.In this study,how hydrothermal temperatures(180,220 and 260℃)influence the molecular-level c... The copper complexing of dissolved organic matter released from hydrochar(HDOM)affects the former’s environmental behavior.In this study,how hydrothermal temperatures(180,220 and 260℃)influence the molecular-level constitutions and Cu(II)binding features of HDOM were elucidated via fourier transform ion cyclotron resonance mass spectrometry and multi-spectroscopic analysis.The findings demonstrated that the almost HDOM molecules had the traits of lower polarity and higher hydrophobicity.As the hydrothermal temperature increased,the molecules with particularly high relative strength gradually disappeared,average molecular weight,percentages of CHON and aliphatic compounds of HDOM reduced while the percentages of CHO and aromatic compounds increased.In general,the fluorescence quenching of Cu(II)weakened as hydrothermal temperature rose and the Cu(II)binding stability constants of fluorophores in HDOM were 4.50–5.31.In addition,the Cu(II) binding order of fluorophores in HDOM showed temperature heterogeneities, andpolysaccharides or aromatic rings of non-fluorescent substances had the fastest responsesto Cu(II) binding. Generally, fluorescent components tend to bind Cu(II) at relatively traceconcentrations (0–40 μmol/L), whereas non-fluorescent substances tend to the bind Cu(II)at relatively higher concentrations (50–100 μmol/L). This study contributed to the predictionof the potential environmental behaviors and risks of Cu(II) at the molecular level afterhydrochar application. 展开更多
关键词 Hydrochar Dissolved organic matter Molecular characterizations Cu(II)binding Two-dimensional correlation analysis(2D-COS)
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Persistent alterations in gray matter in COVID-19 patients experiencing sleep disturbances:a 3-month longitudinal study
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作者 Kaixuan Zhou Gaoxiong Duan +19 位作者 Ying Liu Bei Peng Xiaoyan Zhou Lixia Qin Lingyan Liang Yichen Wei Qingping Zhang Xiaocheng Li Haixia Qin Yinqi Lai Yian Lu Yan Zhang Jiazhu Huang Jinli Huang Yinfei Ouyang Bolin Bin Mingming Zhao Jun Liu Jianrong Yang Demao Deng 《Neural Regeneration Research》 SCIE CAS 2025年第10期3013-3024,共12页
Sleep disturbances are among the most prevalent neuropsychiatric symptoms in individuals who have recovered from severe acute respiratory syndrome coronavirus 2 infections.Previous studies have demonstrated abnormal b... Sleep disturbances are among the most prevalent neuropsychiatric symptoms in individuals who have recovered from severe acute respiratory syndrome coronavirus 2 infections.Previous studies have demonstrated abnormal brain structures in patients with sleep disturbances who have recovered from coronavirus disease 2019(COVID-19).However,neuroimaging studies on sleep disturbances caused by COVID-19 are scarce,and existing studies have primarily focused on the long-term effects of the virus,with minimal acute phase data.As a result,little is known about the pathophysiology of sleep disturbances in the acute phase of COVID-19.To address this issue,we designed a longitudinal study to investigate whether alterations in brain structure occur during the acute phase of infection,and verified the results using 3-month follow-up data.A total of 26 COVID-19 patients with sleep disturbances(aged 51.5±13.57 years,8 women and 18 men),27 COVID-19 patients without sleep disturbances(aged 47.33±15.98 years,9 women and 18 men),and 31 age-and gender-matched healthy controls(aged 49.19±17.51 years,9 women and 22 men)were included in this study.Eleven COVID-19 patients with sleep disturbances were included in a longitudinal analysis.We found that COVID-19 patients with sleep disturbances exhibited brain structural changes in almost all brain lobes.The cortical thicknesses of the left pars opercularis and left precuneus were significantly negatively correlated with Pittsburgh Sleep Quality Index scores.Additionally,we observed changes in the volume of the hippocampus and its subfield regions in COVID-19 patients compared with the healthy controls.The 3-month follow-up data revealed indices of altered cerebral structure(cortical thickness,cortical grey matter volume,and cortical surface area)in the frontal-parietal cortex compared with the baseline in COVID-19 patients with sleep disturbances.Our findings indicate that the sleep disturbances patients had altered morphology in the cortical and hippocampal structures during the acute phase of infection and persistent changes in cortical regions at 3 months post-infection.These data improve our understanding of the pathophysiology of sleep disturbances caused by COVID-19. 展开更多
关键词 brain structure cortical gray matter volume cortical surface area cortical thickness HIPPOCAMPUS magnetic resonance imaging Pittsburgh Sleep Quality Index severe acute respiratory syndrome coronavirus 2 infections sleep disturbances sub-cortical volume
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Efficient multi-millijoule THz wave generation from laser interactions with a cylindrical GaAs waveguide
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作者 Zahra Ghanavati Hamid Reza Zangeneh 《红外与毫米波学报》 北大核心 2025年第4期586-593,共8页
This study involved a comprehensive investigation aimed at achieving efficient multi-millijoule THz wave generation by exploiting the unique properties of cylindrical GaAs waveguides as effective mediators of the conv... This study involved a comprehensive investigation aimed at achieving efficient multi-millijoule THz wave generation by exploiting the unique properties of cylindrical GaAs waveguides as effective mediators of the conversion of laser energy into THz waves.Through meticulous investigation,valuable insights into optimizing THz generation processes for practical applications were unearthed.By investigating Hertz potentials,an eigen-value equation for the solutions of the guided modes(i.e.,eigenvalues)was found.The effects of various param-eters,including the effective mode index and the laser pulse power,on the electric field components of THz radia-tion,including the fundamental TE(transverse electric)and TM(transverse magnetic)modes,were evaluated.By analyzing these factors,this research elucidated the nuanced mechanisms governing THz wave generation within cylindrical GaAs waveguides,paving the way for refined methodologies and enhanced efficiency.The sig-nificance of cylindrical GaAs waveguides extends beyond their roles as mere facilitators of THz generation;their design and fabrication hold the key to unlocking the potential for compact and portable THz systems.This trans-formative capability not only amplifies the efficiency of THz generation but also broadens the horizons of practical applications. 展开更多
关键词 terahertz waves cylindrical waveguides gallium arsenide(GaAs)matter nonlinear optical processes multi-millijoule THz pulses
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Control of toxicity of fine particulate matter emissions in China
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作者 Haotian Zheng 《四川生理科学杂志》 2025年第7期1510-1510,共1页
Fine particulate matter(particulate matter with a diameter of 2.5μm or less;PM2.5)causes millions of premature deaths globally1,but not all particles are equally harmful2-4.Current air-pollution control strategies,pr... Fine particulate matter(particulate matter with a diameter of 2.5μm or less;PM2.5)causes millions of premature deaths globally1,but not all particles are equally harmful2-4.Current air-pollution control strategies,prioritizing PM2.5 mass reduction,have provided considerable health benefits but further refinements based on differences in the toxicity of various emission sources may provide greater benefits5-7.Here we integrated field measurements with air-quality modelling to assess the unequal toxicities of PM2.5 from various anthropogenic sources. 展开更多
关键词 TOXICITY air pollution fine particulate matter emission sources field measurements health benefits fine particulate matter particulate matter PM
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Microbiological mechanisms of lignin-and humus-derived small molecule addition promoting straw conversion into soil organic matter in a sodic soil
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作者 Jingwang LI Lin CHEN +7 位作者 Fengxia YUE Congzhi ZHANG Donghao MA Guixiang ZHOU Jiangli WANG Changdong HAN Biao FENG Jiabao ZHANG 《Pedosphere》 2025年第4期603-616,共14页
Straw return is the main practice used to increase soil organic matter(SOM)in agricultural ecosystems.To increase the efficiency of straw conversion to SOM,a large number of microbial inoculants have been developed.Ho... Straw return is the main practice used to increase soil organic matter(SOM)in agricultural ecosystems.To increase the efficiency of straw conversion to SOM,a large number of microbial inoculants have been developed.However,their effects are poor because of the complex water and temperature conditions,especially under sodic conditions.Small molecules can rapidly shift soil microbial communities and improve their ability to transform exogenous organic matter into SOM,providing a new direction for promoting high-efficiency straw conversion into SOM.In this study,we conducted a^(13)C-labeled straw degradation experiment using small molecules derived from lignin(LSMs)and humus(HSMs)as activators,investigating their effects on the microbial communities and formation of newly formed mineral-associated(^(13)C-MAOM)and particulate(^(13)C-POM)organic matter from^(13)C-labeled straw in both sodic and non-sodic soils.The^(13)C-labeled straw was mainly converted into^(13)C-MAOM,accounting for 73.97%–92.67%of the newly formed SOM.Biopolymer-derived small molecules decreased the exchangeable sodium percentage(ESP),but increased contents of^(13)C-MAOM and^(13)C-POM by shifting microbial communities,strengthening microbial cross-trophic interactions,enhancing enzyme activities,and increasing microbial residues in both soils.Addition of HSMs had greater impacts on^(13)C-MAOM formation than LSM addition.The^(13)C-MAOM and^(13)C-POM formation negatively correlated with ESP,but positively correlated with microbial cross-trophic interactions and enzyme activities in both soils.Our results suggest that biopolymer-derived small molecules promote^(13)C-MAOM and^(13)C-POM formation associated with microbial cross-trophic interactions between protistan predators and primary decomposers.Our study provides scientific support for future attempts to stimulate microbial cross-trophic interactions for boosting SOM accumulation under stressed conditions. 展开更多
关键词 biopolymer-derived small molecule microbial community mineral-associated organic matter particulate organic matter PROTIST trophic interaction
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Intersection of mitochondrial dysfunction and myelination:An overlooked aspect in neurodevelopmental disorders
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作者 Ariel Nir Sade Gal Wiener Boaz Barak 《Neural Regeneration Research》 2026年第2期659-660,共2页
Neurodevelopmental processes represent a finely tuned interplay between genetic and environmental factors,shaping the dynamic landscape of the developing brain.A major component of the developing brain that enables th... Neurodevelopmental processes represent a finely tuned interplay between genetic and environmental factors,shaping the dynamic landscape of the developing brain.A major component of the developing brain that enables this dynamic is the white matter(WM),known to be affected in neurodevelopmental disorders(NDDs)(Rokach et al.,2024).WM formation is mediated by myelination,a multifactorial process driven by neuro-glia interactions dependent on proper neuronal functionality(Simons and Trajkovic,2006).Another key aspect of neurodevelopmental abnormalities involves neuronal dynamics and function,with recent advances significantly enhancing our understanding of both neuronal and glial mitochondrial function(Devine and Kittler,2018;Rojas-Charry et al.,2021).Energy homeostasis in neurons,attributed largely to mitochondrial function,is critical for proper functionality and interactions with oligodendrocytes(OLs),the cells forming myelin in the brain’s WM.We herein discuss the interplay between these processes and speculate on potential dysfunction in NDDs. 展开更多
关键词 neurodevelopmental disorders ndds rokach white matter developing brain MYELINATION neurodevelopmental processes mitochondrial dysfunction white matter wm known developing braina
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Bio-inspired wet/lubricious/adhesive soft matter and performance control in-between
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作者 Shuanhong Ma Desheng Liu +6 位作者 Wenbo Sheng Yanfei Ma Bin Li Xiaoduo Zhao Xiaolong Wang Feng Zhou Weimin Liu 《Advanced Bionics》 2025年第1期29-56,共28页
Nature evolves soft but structural architectures with typical wet/lubricous/adhesive behavior,as well as tunable interface functionalities,such as superhydrophilicity,superhydrophobic,superlubricity,high adhesion,etc.... Nature evolves soft but structural architectures with typical wet/lubricous/adhesive behavior,as well as tunable interface functionalities,such as superhydrophilicity,superhydrophobic,superlubricity,high adhesion,etc.In order to simulate this,new chemistry modification methods,novel polymers materials and advanced manufacture techniques are developed for engineering diverse bioinspired wet/lubricous/adhesive soft matter systems.This review focuses on two typical interface functionalities of soft architectures in nature:wet lubrication and wet adhesion.Correspondingly,systematic summaries of recent progress for constructing bioinspired wet/lubricious/adhesive soft matter systems are proposed,including the surface grafting methods to construct hydrophilic wet lubrication surfaces,the bionic design of mechanically robust and structured soft matter lubrication materials,the novel preparation of high-performance biomimetic wet adhesion materials,and the advanced manufacture of 3D soft matter-based wet/lubricious devices.Subsequently,the current strategies relying on diverse regulation factors including surface hydration/roughness,surface intrinsic states,bulk mechanics,as well as multi-factors synergy,are introduced and discussed for achieving dynamic friction or adhesion control of bioinspired soft matter lubrication/adhesion systems.Finally,the existing problems,challenges and future development directions of bioinspired wet/lubricious/adhesive soft matter materials and devices are discussed.This review provides clear guidance for designing bioinspired soft matter-based lubrication,adhesion,or adhesion-lubrication switchable systems,and would act as a necessary research handbook in the field of surface/interface wettability engineering,bioengineering,medical devices,soft robotics,etc. 展开更多
关键词 BIOINSPIRED Soft matter WETTABILITY LUBRICATION Adhesion Friction control
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Gas Chromatographic Analysis of the Methanogenic Potential of Lignocellulosic Biomass Consisting of Banana Residues in Tambacounda, Senegal
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作者 Haroun Ali Adannou Hamza Aziber Ousman Ndiaye Mouhamadou Lamine 《Open Journal of Applied Sciences》 2025年第1期187-201,共15页
The residual biomass composed of pseudo trunks and banana leaves is very important and poorly valued. There is very little quantified data on the deposits of residual biomass from banana plantations in Senegal and in ... The residual biomass composed of pseudo trunks and banana leaves is very important and poorly valued. There is very little quantified data on the deposits of residual biomass from banana plantations in Senegal and in particular in the Tambacounda region. In this work, we seek to evaluate the methanogenic potential and to valorize this biomass in biogas and biofertilizer. The laboratory experiment lasted approximately 35 days. During this time, the methanogenic microorganisms degrade the organic residue provided, which results in the production of biogas. At the end of the reactions, the rate of biogas production drops, indicating the end of the biodegradation of organic matter. Biogas production is measured over time and the composition of the biogas produced is analyzed by gas chromatography (GC) or by an infrared analyzer. The methane potential of each sample is determined from the cumulative quantity of methane produced in each flask representing a digestion system. The measurement can be expressed in m3 of CH4 per tonne of dry matter or per tonne of raw material. The first challenge of this study therefore lies in the acquisition of reliable and usable data to quantify the methanizable biomass. This study will allow us not only to evaluate the quantities of pseudo trunks and banana leaves available in a plot after harvest but also to test the biogas and methane production potential (BMP test) of this substrate and therefore determine the expected biogas production of this biomass. 展开更多
关键词 Residual Biomass BANANA Tambacounda Laboratory Organic Matter Infrared Analyzer
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Response of organic matter pore development to functional groups in overmature marine shale:Insights from AFM-IR spectroscopy
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作者 ZHAO Jianhua LIU Keyu +8 位作者 ZHAO Shenghui HU Qinhong WU Wei CHEN Yang LIU Guoheng LI Junqian YU Lingjie YOU Zuhui WANG Ye 《Petroleum Exploration and Development》 2025年第2期445-458,共14页
Taking the Lower Silurian Longmaxi Formation shale in the Sichuan Basin as an example,this study employs atomic force microscopy-based infrared(AFM-IR)spectroscopy to analyze the submicron-scale molecular functional g... Taking the Lower Silurian Longmaxi Formation shale in the Sichuan Basin as an example,this study employs atomic force microscopy-based infrared(AFM-IR)spectroscopy to analyze the submicron-scale molecular functional groups of different types and occurrences of organic matter.Combined with the quantitative evaluation of pore development via scanning electron microscopy(SEM),the response of organic pore formation and evolution mechanisms to chemical composition and structural evolution of organic matter in overmature marine shale is investigated.The results indicate that the AFM-IR spectra of graptolite periderms and pyrobitumen in shale are dominated by the stretching vibrations of conjugated C=C bonds in aromatic compounds at approximately 1600 cm-1,with weak absorption peaks near 1375,1450 and 1720 cm-1,corresponding to aliphatic chains and carbonyl/carboxyl functional groups.Overall,the AFM-IR structural indices(A and C factors)of organic matter show a strong correlation with visible porosity in shales of equivalent maturity.Lower A and C factor values correlate with enhanced development of organic pores,which is associated with the detachment of more aliphatic chains and oxygen-containing functional groups during thermal evolution.Pyrobitumen-clay mineral composites generally exhibit superior pore development,likely attributable to clay mineral dehydration participating in hydrocarbon generation reactions that promote the removal of more functional groups.Additionally,hydrocarbon generation within organic-clay composites during high-over mature stages may induce volumetric expansion,resulting in microfracturing and hydrocarbon expulsion.The associated higher hydrocarbon expulsion rates promote the formation of larger pores and fracture-shaped pores along the flake-shaped clay minerals.This study highlights that the research of submicron-scale molecular functional groups provides a deeper understanding of organic matter evolution and pores development mechanisms in overmature shales,thereby offering critical theoretical parameters for reservoir evaluation in shale oil and gas exploration. 展开更多
关键词 AFM-IR spectroscopy organic matter molecular functional groups organic matter pore development Longmaxi Formation shale
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Shenlian Extract Protects against Ultrafine Particulate Matter-Aggravated Myocardial Ischemic Injury by Inhibiting Inflammation and Cell Apoptosis
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作者 Shuiqing Qu Yan Liang +7 位作者 Shuoqiu Deng Yu Li Yue Dai Chengcheng Liu Tuo Liu Luqi Wang Lina Chen Yujie Li 《Biomedical and Environmental Sciences》 2025年第2期206-218,共13页
Objective Emerging evidence suggests that exposure to ultrafine particulate matter(UPM,aerodynamic diameter<0.1μm)is associated with adverse cardiovascular events.Previous studies have found that Shenlian(SL)extra... Objective Emerging evidence suggests that exposure to ultrafine particulate matter(UPM,aerodynamic diameter<0.1μm)is associated with adverse cardiovascular events.Previous studies have found that Shenlian(SL)extract possesses anti-inflammatory and antiapoptotic properties and has a promising protective effect at all stages of the atherosclerotic disease process.In this study,we aimed to investigated whether SL improves UPM-aggravated myocardial ischemic injury by inhibiting inflammation and cell apoptosis.Methods We established a mouse model of MI+UPM.Echocardiographic measurement,measurement of myocardialinfarct size,biochemical analysis,enzyme-linked immunosorbent assay(ELISA),histopathological analysis,Transferase dUTP Nick End Labeling(TUNEL),Western blotting(WB),Polymerase Chain Reaction(PCR)and so on were used to explore the anti-inflammatory and antiapoptotic effects of SL in vivo and in vitro.Results SL treatment can attenuate UPM-induced cardiac dysfunction by improving left ventricular ejection fraction,fractional shortening,and decreasing cardiac infarction area.SL significantly reduced the levels of myocardial enzymes and attenuated UPM-induced morphological alterations.Moreover,SL significantly reduced expression levels of the inflammatory cytokines IL-6,TNF-α,and MCP-1.UPM further increased the infiltration of macrophages in myocardial tissue,whereas SL intervention reversed this phenomenon.UPM also triggered myocardial apoptosis,which was markedly attenuated by SL treatment.The results of in vitro experiments revealed that SL prevented cell damage caused by exposure to UPM combined with hypoxia by reducing the expression of the inflammatory factor NF-κB and inhibiting apoptosis in H9c2 cells.Conclusion Overall,both in vivo and in vitro experiments demonstrated that SL attenuated UPMaggravated myocardial ischemic injury by inhibiting inflammation and cell apoptosis.The mechanisms were related to the downregulation of macrophages infiltrating heart tissues. 展开更多
关键词 Ultrafine particulate matter Shenlian extract INFLAMMATION Apoptosis MACROPHAGE
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