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Timing effect of high temperature exposure on the plasticity of internode and plant architecture in maize
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作者 Binbin Li Xianmin Chen +6 位作者 Tao Deng Xue Zhao Fang Li Bingchao Zhang Xin Wang Si Shen Shunli Zhou 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期551-565,共15页
The occurrence of high temperature(HT)in crop production is becoming more frequent and unpredictable with global warming,severely threatening food security.The state of an organ’s growth and development is largely de... The occurrence of high temperature(HT)in crop production is becoming more frequent and unpredictable with global warming,severely threatening food security.The state of an organ’s growth and development is largely determined by the temperature conditions it is exposed to over time.Maize is the main cereal crop,and its stem growth and plant architecture are closely related to lodging resistance,and especially sensitive to temperature.However,systematic research on the timing effect of HT on the sequentially developing internode and stem is currently lacking.To identify the timing effect of HT on the morphology and plasticity of the stem in maize,two hybrids(Zhengdan 958(ZD958),Xianyu 335(XY335))characterized by distinct morphological traits in the stem were exposed to a 7-day HT treatment from the V6 to V17 stages(Vn presents the vegetative stage with n leaves fully expanded)in 2019-2020.The results demonstrated that exposure to HT during V6-V12 accelerated the rapid elongation of stems.For instance,HT occurring at V7 and V12 specifically promoted the lengths and weights of the 3rd-5th and 9th-11th internodes,respectively.Meanwhile,HT slowed the growth of internodes adjacent to the promoted internodes.Interestingly,compared with control,the plant height was significantly increased soon after HT treatment,but the promotion effect became narrower at the subsequent flowering stage,demonstrating a self-adjusting mechanism in the maize plant in response to HT.Importantly,HT altered the plant architectures,including a rising of the ear position and increase in the ear position coefficient.XY335 exhibited greater sensitivity in stem development than ZD958 under HT treatment.These findings improve our systematic understanding of the plasticity of internode and plant architecture in response to the timing of HT exposure. 展开更多
关键词 MAIZE high temperature internode growth plasticity plant architecture
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Incubation temperature induced developmental plasticity of cold responsive physiological phenotypes in Japanese Quails
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作者 Yingxin Kou Rongmiao Zhang +3 位作者 Xiaoqian Li Na Zhu Yihang Huang Shuping Zhang 《Avian Research》 SCIE CSCD 2024年第3期385-394,共10页
Embryonic development is a critical period for phenotype formation.Environmental variation during embryonic development can induce changes in postnatal phenotypes of animals.The thyroxine secretion and aerobic metabol... Embryonic development is a critical period for phenotype formation.Environmental variation during embryonic development can induce changes in postnatal phenotypes of animals.The thyroxine secretion and aerobic metabolic activity of small birds are important phenotypes closely related to their winter survival.In the context of climate change,it is necessary to determine whether temperature variation during incubation in birds leads to developmental plasticity of these cold responsive phenotypes.We incubated Japanese Quail(Coturnix japonica)eggs at 36.8℃,37.8℃,and 38.8℃,and raised the chicks to 35-day old at 22℃with same raising conditions,then all the quails were exposed to gradually temperature dropping environment(from 15℃to 0℃).After cold treatment,serum T3 level,resting metabolic rate,skeletal muscle and liver metabolomes of the birds were measured.The serum T3 levels were significantly lower in the 38.8℃group and significantly higher in the 36.8℃group compared to the 37.8℃group.The metabolic rate in the 38.8℃group was significantly lower compared to the 37.8℃group.Compared with the 37.8℃group,metabolites involved in the tricarboxylic acid cycle in the liver were significantly lower in the 38.8℃group,and metabolites related to lipid oxidation metabolism and fatty acid biosynthesis were significantly lower in the skeletal muscles in the 38.8℃group but significantly higher in the 36.8℃group.These results indicate that incubation temperature variation can lead to developmental plasticity in cold responsive physiological phenotypes.Higher incubation temperature may impair the capacity of birds coping with cold challenge. 展开更多
关键词 Cold response Developmental plasticity Incubation temperature Metabolic rate Metabolomes Precocial bird THYROXIN
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Neural stem cells promote neuroplasticity: a promising therapeutic strategy for the treatment of Alzheimer’s disease 被引量:1
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作者 Jun Chang Yujiao Li +4 位作者 Xiaoqian Shan Xi Chen Xuhe Yan Jianwei Liu Lan Zhao 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第3期619-628,共10页
Recent studies have demonstrated that neuroplasticity,such as synaptic plasticity and neurogenesis,exists throughout the normal lifespan but declines with age and is significantly impaired in individuals with Alzheime... Recent studies have demonstrated that neuroplasticity,such as synaptic plasticity and neurogenesis,exists throughout the normal lifespan but declines with age and is significantly impaired in individuals with Alzheimer’s disease.Hence,promoting neuroplasticity may represent an effective strategy with which Alzheimer’s disease can be alleviated.Due to their significant ability to self-renew,differentiate,and migrate,neural stem cells play an essential role in reversing synaptic and neuronal damage,reducing the pathology of Alzheimer’s disease,including amyloid-β,tau protein,and neuroinflammation,and secreting neurotrophic factors and growth factors that are related to plasticity.These events can promote synaptic plasticity and neurogenesis to repair the microenvironment of the mammalian brain.Consequently,neural stem cells are considered to represent a potential regenerative therapy with which to improve Alzheimer’s disease and other neurodegenerative diseases.In this review,we discuss how neural stem cells regulate neuroplasticity and optimize their effects to enhance their potential for treating Alzheimer’s disease in the clinic. 展开更多
关键词 Alzheimer’s disease amyloid-β cell therapy extracellular vesicle neural stem cell synaptic plasticity tau
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3'-Deoxyadenosin alleviates methamphetamine-induced aberrant synaptic plasticity and seeking behavior by inhibiting the NLRP3 inflammasome 被引量:1
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作者 Yize Qi Yao Zhou +8 位作者 Jiyang Li Fangyuan Zhu Gengni Guo Can Wang Man Yu Yijie Wang Tengfei Ma Shanwu Feng Li Zhou 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第10期2270-2280,共11页
Methamphetamine addiction is a brain disorder characterized by persistent drug-seeking behavior, which has been linked with aberrant synaptic plasticity. An increasing body of evidence suggests that aberrant synaptic ... Methamphetamine addiction is a brain disorder characterized by persistent drug-seeking behavior, which has been linked with aberrant synaptic plasticity. An increasing body of evidence suggests that aberrant synaptic plasticity is associated with the activation of the NOD-like receptor family pyrin domain containing-3(NLRP3) inflammasome. 3′-Deoxyadenosin, an active component of the Chinese fungus Cordyceps militaris, has strong anti-inflammatory effects. However, whether 3′-deoxyadenosin attenuates methamphetamine-induced aberrant synaptic plasticity via an NLRP3-mediated inflammatory mechanism remains unclear. We first observed that 3′-deoxyadenosin attenuated conditioned place preference scores in methamphetamine-treated mice and decreased the expression of c-fos in hippocampal neurons. Furthermore, we found that 3′-deoxyadenosin reduced the aberrant potentiation of glutamatergic transmission and restored the methamphetamine-induced impairment of synaptic plasticity. We also found that 3′-deoxyadenosin decreased the expression of NLRP3 and neuronal injury. Importantly, a direct NLRP3 deficiency reduced methamphetamine-induced seeking behavior, attenuated the impaired synaptic plasticity, and prevented neuronal damage. Finally, NLRP3 activation reversed the effect of 3′-deoxyadenosin on behavior and synaptic plasticity, suggesting that the anti-neuroinflammatory mechanism of 3′-deoxyadenosin on aberrant synaptic plasticity reduces methamphetamine-induced seeking behavior. Taken together, 3′-deoxyadenosin alleviates methamphetamine-induced aberrant synaptic plasticity and seeking behavior by inhibiting the NLRP3 inflammasome. 展开更多
关键词 3′-deoxyadenosin hippocampus long-term potentiation METHAMPHETAMINE NOD-like receptor family pyrin domain containing-3(NLRP3)inflammasome synaptic plasticity
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瓜蒌薤白半夏汤联合银杏酮酯分散片对冠心病心绞痛患者心电图、MMP-9、EMPs水平的影响分析
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作者 谢相屹 余慧娟 +2 位作者 孙刚 王丹 周琦 《中华中医药学刊》 CAS 北大核心 2024年第5期65-68,共4页
目的观察瓜蒌薤白半夏汤联合银杏酮酯分散片对冠心病心绞痛患者心电图、MMP-9、EMPs水平的影响分析。方法纳入120例冠心病稳定型心绞痛痰浊闭阻证患者,按随机数表法随机分为观察组及对照组各60例。两组均给予冠心病稳定型心绞痛治疗常... 目的观察瓜蒌薤白半夏汤联合银杏酮酯分散片对冠心病心绞痛患者心电图、MMP-9、EMPs水平的影响分析。方法纳入120例冠心病稳定型心绞痛痰浊闭阻证患者,按随机数表法随机分为观察组及对照组各60例。两组均给予冠心病稳定型心绞痛治疗常规用药,对照组给予银杏酮酯分散片,观察组在对照组基础上联合瓜蒌薤白半夏汤治疗,两组均治疗8周。治疗结束后观察两组治疗前后临床疗效、心绞痛发作情况、中医临床症状积分、心电图疗效、血脂水平及血管性血友病因子(von willebrand Factor,vWF)、基质金属蛋白酶-9(matrix metallopeptidase-9,MMP-9)、内皮细胞微粒(endothelial microparticles,EMPs)水平的变化情况。结果治疗8周后,观察组总有效率为88.33%(53/60),显著高于对照组的71.67%(43/60)(P<0.05);两组患者心绞痛发作次数及持续时间均较治疗前有显著改善(P<0.05),且观察组显著优于对照组(P<0.05);治疗后两组中医临床症状积分均有显著改善,观察组在胸闷、胸痛、气短喘促、痰多纳呆、身体困重症状积分显著优于对照组(P<0.05);观察组心电图总有效率为85.00%(51/60),显著高于对照组的60.00%(36/60)(P<0.05);同时两组患者治疗后总胆固醇(total cholesterol,TC)、甘油三酯(triglyceride,TG)、高密度脂蛋白(high-density lipoprotein cholesterol,HDL-C)、低密度脂蛋白(low-density lipoprotein cholesterol,LDL-C)水平也明显改善(P<0.05),观察组TG、TC及LDL-C显著低于对照组(P<0.05),HDL-C则高于对照组(P<0.05);对照组及观察组经治疗后vWF、MMP-9、EMPs水平均较治疗前提升降低(P<0.05),同时观察组改善显著优于对照组(P<0.05)。结论冠心病稳定型心绞痛在常规治疗基础上采用瓜蒌薤白半夏汤联合银杏酮酯分散片治疗可有效减少患者心绞痛发作,改善临床症状及心电图情况,调节血脂水平,降低患者vWF、MMP-9、EMPs水平,提高临床治疗效果。 展开更多
关键词 瓜蒌薤白半夏汤 银杏酮酯分散片 冠心病心绞痛 MMP-9 emps
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Manipulation of photosensory and circadian signaling restricts phenotypic plasticity in response to changing environmental conditions in Arabidopsis
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作者 Martin William Battle Scott Fraser Ewing +6 位作者 Cathryn Dickson Joseph Obaje Kristen N.Edgeworth Rebecca Bindbeutel Rea LAntoniou-Kourounioti Dmitri A.Nusinow Matthew Alan Jones 《Molecular Plant》 SCIE CSCD 2024年第9期1458-1471,共14页
Plants exploit phenotypic plasticity to adapt their growth and development to prevailing environmental conditions.Interpretation of light and temperature signals is aided by the circadian system,which provides a tempo... Plants exploit phenotypic plasticity to adapt their growth and development to prevailing environmental conditions.Interpretation of light and temperature signals is aided by the circadian system,which provides a temporal context.Phenotypic plasticity provides a selective and competitive advantage in nature but is obstructive during large-scale,intensive agricultural practices since economically important traits(including vegetative growth and flowering time)can vary widely depending on local environmental condi-tions.This prevents accurate prediction of harvesting times and produces a variable crop.In this study,we sought to restrict phenotypic plasticity and circadian regulation by manipulating signaling systems that govern plants'responses to environmental signals.Mathematical modeling of plant growth and develop-ment predicted reduced plant responses to changing environments when circadian and light signaling pathways were manipulated.We tested this prediction by utilizing a constitutively active allele of the plant photoreceptor phytochrome B,along with disruption of the circadian systemvia mutation of EARLYFLOW-ERING3.We found that these manipulations produced plants that are less responsive to light and temper-ature cues and thus fail to anticipate dawn.These engineered plants have uniform vegetative growth and flowering time,demonstrating how phenotypic plasticity can be limited while maintaining plant productiv-ity.This has significant implications for future agriculture in both open fields and controlled environments. 展开更多
关键词 CIRCADIAN developmental plasticity phenotypic plasticity external coincidence light temperature
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Recent Advance in Synaptic Plasticity Modulation Techniques for Neuromorphic Applications
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作者 Yilin Sun Huaipeng Wang Dan Xie 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第10期403-434,共32页
Manipulating the expression of synaptic plasticity of neuromorphic devices provides fascinating opportunities to develop hardware platforms for artifi-cial intelligence.However,great efforts have been devoted to explo... Manipulating the expression of synaptic plasticity of neuromorphic devices provides fascinating opportunities to develop hardware platforms for artifi-cial intelligence.However,great efforts have been devoted to exploring biomimetic mechanisms of plasticity simulation in the last few years.Recent progress in various plasticity modulation techniques has pushed the research of synaptic electronics from static plasticity simulation to dynamic plasticity modulation,improving the accuracy of neuromorphic computing and providing strategies for implementing neuromorphic sensing functions.Herein,several fascinating strategies for synap-tic plasticity modulation through chemical techniques,device structure design,and physical signal sensing are reviewed.For chemical techniques,the underly-ing mechanisms for the modification of functional materials were clarified and its effect on the expression of synaptic plasticity was also highlighted.Based on device structure design,the reconfigurable operation of neuromorphic devices was well demonstrated to achieve programmable neuromorphic functions.Besides,integrating the sensory units with neuromorphic processing circuits paved a new way to achieve human-like intelligent perception under the modulation of physical signals such as light,strain,and temperature.Finally,considering that the relevant technology is still in the basic exploration stage,some prospects or development suggestions are put forward to promote the development of neuromorphic devices. 展开更多
关键词 plasticity modulation Dynamic plasticity Chemical techniques Programmable operation Neuromorphic sensing
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Temperature-jump tensile tests to induce optimized TRIP/TWIP effect in a metastable austenitic stainless steel
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作者 Mohammad Javad Sohrabi Hamed Mirzadeh +2 位作者 Saeed Sadeghpour Abdol Reza Geranmayeh Reza Mahmudi 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第9期2025-2036,共12页
In the present work,plastic deformation mechanisms were initially tailored by adjusting the deformation temperature in the range of 0 to 200℃ in AISI 304L austenitic stainless steel,aiming to optimize the strength-du... In the present work,plastic deformation mechanisms were initially tailored by adjusting the deformation temperature in the range of 0 to 200℃ in AISI 304L austenitic stainless steel,aiming to optimize the strength-ductility synergy.It was shown that the combined twinning-induced plasticity(TWIP)/transformation-induced plasticity(TRIP)effects and a wider strain range for the TRIP effect up to higher strains by adjusting the deformation temperature are good strategies to improve the strength-ductility synergy of this metastable stainless steel.In this regard,by consideration of the observed temperature-dependency of plastic deformation,the controlled sequence of TWIP and TRIP effects for archiving superior strength-ductility trade-off was intended by the pre-designed temperature jump tensile tests.Accordingly,the optimum tensile toughness of 846 MJ/m^(3) and total elongation to 133% were obtained by this strategy via exploiting the advantages of the TWIP effect at 100℃ and the TRIP effect at 25℃ at the later stages of the straining.Consequently,a deformation-temperature-transformation(DTT)diagram was developed for this metastable alloy.Moreover,based on work-hardening analysis,it was found that the main phenomenon constraining further improvement in the ductility and strengthening was the yielding of the deformation-induced α′-martensite. 展开更多
关键词 metastable stainless steels transformation-induced plasticity twinning-induced plasticity stacking fault energy mechanical properties
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Mitochondrial recruitment in myelin:an anchor for myelin dynamics and plasticity?
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作者 Jean-David M.Gothié Timothy E.Kennedy 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1401-1402,共2页
Optimal propagation of neuronal electrical impulses depends on the insulation of axons by myelin,produced in the central nervous system by oligodendrocytes.Myelin is an extension of the oligodendrocyte plasma membrane... Optimal propagation of neuronal electrical impulses depends on the insulation of axons by myelin,produced in the central nervous system by oligodendrocytes.Myelin is an extension of the oligodendrocyte plasma membrane,which wraps around an axon to form a compact multi-layered sheath.Myelin is composed of a substantially higher proportion of lipids compared to other biological membranes and enriched in a small number of specialized proteins. 展开更多
关键词 plasticity insulation DYNAMICS
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Perspectives in human brain plasticity sparked by glioma invasion:from intraoperative(re)mappings to neural reconfigurations
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作者 Sam Ng Hugues Duffau Guillaume Herbet 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期947-948,共2页
Exploring the aptitude of the human brain to compensate functional consequences of a lesion damaging its structural architecture is a key challenge to improve patient care in various neurological diseases,to optimize ... Exploring the aptitude of the human brain to compensate functional consequences of a lesion damaging its structural architecture is a key challenge to improve patient care in various neurological diseases,to optimize neuroscientifically-informed strategies of postlesional rehabilitation,and ultimately to develop innovative neuro-regenerative therapies.The term‘plasticity’,initially referring to the intrinsic propensity of neurons to modulate their synaptic transmission in a learning situation,was progressively transposed to brain injury research and clinical neurosciences.Indeed,in the event of brain damage,adaptive mechanisms of compensation allow a partial reshaping of the structure and activities of the central nervous system,thus permitting to some extent the maintenance of brain functions. 展开更多
关键词 plasticity figuration consequences
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Glial progenitor heterogeneity and plasticity in the adult spinal cord
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作者 Haichao Wei Jia Qian Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第12期2567-2568,共2页
Glial progenitor cells were reported to have the capacity to generate various types of cells in both the central nervous system(CNS)and peripheral nervous system.Glial progenitor cells can respond to diverse environme... Glial progenitor cells were reported to have the capacity to generate various types of cells in both the central nervous system(CNS)and peripheral nervous system.Glial progenitor cells can respond to diverse environmental signals and transform into distinct populations,each serving specific functions.Notably,the adult spinal cord hosts various populations of glial progenitors,a region integral to the central nervous system.During development,glial progenitors express glial fibrillary acidic protein(GFAP;Dimou and Gotz,2014).However,the specific identities of GFAP-expressing progenitors in the adult spinal cord were not thoroughly investigated. 展开更多
关键词 functions plasticity thoroughly
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From mice to humans:a need for comparable results in mammalian neuroplasticity
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作者 Marco Ghibaudi Enrica Boda Luca Bonfanti 《Neural Regeneration Research》 SCIE CAS 2025年第2期464-466,共3页
Brain plasticity-A universal tool with many variations:The study of brain plasticity has been gaining interest since almost a century and has now reached a huge amount of information(>80,000 results in PubMed).Over... Brain plasticity-A universal tool with many variations:The study of brain plasticity has been gaining interest since almost a century and has now reached a huge amount of information(>80,000 results in PubMed).Overall,different types of plasticity,including stem cell-driven genesis of new neurons(adult neurogenesis),cells in arrested maturation(dormant neurons),neuro-glial and synaptic plasticity,can coexist and contribute to grant plastic changes in the brain,from a cellular to system level(Benedetti and Couillard-Despres,2022;Bonfanti et al.,2023). 展开更多
关键词 plasticity al. ARREST
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Contribution of mechanical forces to structural synaptic plasticity:insights from 3D cellular motility mechanisms
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作者 Rita O.Teodoro Mafalda Ribeiro Ramos Lara Carvalho 《Neural Regeneration Research》 SCIE CAS 2025年第7期1995-1996,共2页
Cells,tissues,and organs are constantly subjected to the action of mechanical forces from the extracellular environment-and the nervous system is no exception.Cell-intrinsic properties such as membrane lipid compositi... Cells,tissues,and organs are constantly subjected to the action of mechanical forces from the extracellular environment-and the nervous system is no exception.Cell-intrinsic properties such as membrane lipid composition,abundance of mechanosensors,and cytoskeletal dynamics make cells more or less likely to sense these forces.Intrinsic and extrinsic cues are integrated by cells and this combined information determines the rate and dynamics of membrane protrusion growth or retraction(Yamada and Sixt,2019).Cell protrusions are extensions of the plasma membrane that play crucial roles in diverse contexts such as cell migration and neuronal synapse formation.In the nervous system,neurons are highly dynamic cells that can change the size and number of their pre-and postsynaptic elements(called synaptic boutons and dendritic spines,respectively),in response to changes in the levels of synaptic activity through a process called plasticity.Synaptic plasticity is a hallmark of the nervous system and is present throughout our lives,being required for functions like memory formation or the learning of new motor skills(Minegishi et al.,2023;Pillai and Franze,2024). 展开更多
关键词 plasticity STRUCTURAL MECHANISMS
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Age-related differences in long-term potentiation-like plasticity and shortlatency afferent inhibition and their association with cognitive function
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作者 Qian Lu Sisi Huang +7 位作者 Tianjiao Zhang Jie Song Manyu Dong Yilun Qian Jing Teng Tong Wang Chuan He Ying Shen 《General Psychiatry》 CSCD 2024年第1期73-82,共10页
Background The neurophysiological differences in cortical plasticity and cholinergic system function due to ageing and their correlation with cognitive function remain poorly understood.Aims To reveal the differences ... Background The neurophysiological differences in cortical plasticity and cholinergic system function due to ageing and their correlation with cognitive function remain poorly understood.Aims To reveal the differences in long-term potentiation(LTP)-like plasticity and short-latency afferent inhibition(SAl)between older and younger individuals,alongside their correlation with cognitive function using transcranial magnetic stimulation(TMS).Methods The cross-sectional study involved 31 younger adults aged 18-30 and 46 older adults aged 60-80.All participants underwent comprehensive cognitive assessments and a neurophysiological evaluation based on TMS.Cognitive function assessments included evaluations of global cognitive function,language,memory and executive function.The neurophysiological assessment included LTP-like plasticity and SAl.Results The findings of this study revealed a decline in LTP among the older adults compared with the younger adults(wald χ^(2)=3.98,p=0.046).Subgroup analysis further demonstrated a significant reduction in SAl level among individuals aged 70-80 years in comparison to both the younger adults(SAI(N20)):(t=-3.37,p=0.018);SAl(N20+4):(t=-3.13,p=0.038)and those aged 60-70(SAl(N20)):(t=3.26,p=0.025);SAl(N20+4):(t=-3.69,p=0.006).Conversely,there was no notable difference in SAl level between those aged 60-70 years and the younger group.Furthermore,after employing the Bonferroni correction,the correlation analysis revealed that only the positive correlation between LTP-like plasticity and language function(r=0.61,p<0.001)in the younger group remained statistically significant.Conclusions During the normal ageing process,a decline in synaptic plasticity may precede cholinergic system dysfunction.In individuals over 60 years of age,there is a reduction in LTP-like plasticity,while a decline in cholinergic system function is observed in those over 70.Thus,the cholinergic system may play a vital role in preventing cognitive decline during normal ageing.In younger individuals,LTP-like plasticity might represent a potential neurophysiological marker for language function. 展开更多
关键词 function YOUNGER plasticity
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Temperature effect on nanotwinned Ni under nanoindentation using molecular dynamic simulation
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作者 何茜 徐子翼 倪玉山 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期603-612,共10页
Temperature effect on atomic deformation of nanotwinned Ni (nt-Ni) under localized nanoindentation is investigated in comparison with nanocrystalline Ni (nc-Ni) through molecular simulation.The nt-Ni exhibits enhanced... Temperature effect on atomic deformation of nanotwinned Ni (nt-Ni) under localized nanoindentation is investigated in comparison with nanocrystalline Ni (nc-Ni) through molecular simulation.The nt-Ni exhibits enhanced critical load and hardness compared to nc-Ni,where perfect,stair-rod and Shockley dislocations are activated at (111),(111) and (111) slip planes in nt-Ni compared to only SSockley dislocation nucleation at (111) and (111) slip planes of nc-Ni.The nt-Ni exhibits a less significant indentation size effect in comparison with nc-Ni due to the dislocation slips hindrance of the twin boundary.The atomic deformation associated with the indentation size effect is investigated during dislocation transmission.Different from the decreasing partial slips parallel to the indenter surface in nc-Ni with increasing temperature,the temperaturedependent atomic deformation of nt-Ni is closely related to the twin boundary:from the partial slips parallel to the twin boundary (~10 K),to increased confined layer slips and decreased twin migration(300 K–600 K),to decreased confined layer slips and increased dislocation interaction of dislocation pinning and dissociation (900 K–1200 K).Dislocation density and atomic structure types through quantitative analysis are implemented to further reveal the above-mentioned dislocation motion and atomic structure alteration.Our study is helpful for understanding the temperature-dependent plasticity of twin boundary in nanotwinned materials. 展开更多
关键词 NANOINDENTATION twin boundary plastic deformation molecular dynamics simulation
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Superplasticity of fine-grained Mg-10Li alloy prepared by severe plastic deformation and understanding its deformation mechanisms
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作者 H.T.Jeong S.W.Lee W.J.Kim 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期316-331,共16页
The superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)with a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the HCPαph... The superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)with a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the HCPαphase,were examined in a temperature range of 473 K to 623 K.The microstructural refinement of this alloy was achieved by employing high-ratio differential speed rolling.The best superplasticity was achieved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),where tensile elongations of 550±600%were obtained.During the heating and holding stage of the tensile samples prior to tensile loading,a significant increase in grain size was observed at temperatures above 573 K.Therefore,it was important to consider this effect when analyzing and understanding the superplastic deformation behavior and mechanisms.In the investigated strain rate range,the superplastic flow at low strain rates was governed by lattice diffusion-controlled grain boundary sliding,while at high strain rates,lattice diffusion-controlled dislocation climb creep was the rate-controlling deformation mechanism.It was concluded that solute drag creep is unlikely to occur.During the late stages of deformation at 523 K,it was observed that grain boundary sliding led to the agglomeration of theαphase,resulting in significant strain hardening.Deformation mechanism maps were constructed forβ-Mg-Li alloys in the form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using the constitutive equations for various deformation mechanisms derived based on the data of the current tests. 展开更多
关键词 Magnesium-lithium alloy SUPERplasticity Severe plastic deformation Grain size Grain growth
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Detection of Bisphenol A (BPA) in Plastic Bottles Using Vertical Cultivation at Various Temperatures
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作者 Karwan Alkaradaghi Tara Ali +2 位作者 Nadhir Al-Ansari Polla Khanaqa Jan Laue 《Journal of Environmental Protection》 2024年第6期656-671,共16页
Polycarbonate plastics containing bisphenol A (BPA) used to manufacture drinking water bottles. Kurdistan region in northern Iraq is a developed area with increased pollution from plastic bottles. Trace amounts of BPA... Polycarbonate plastics containing bisphenol A (BPA) used to manufacture drinking water bottles. Kurdistan region in northern Iraq is a developed area with increased pollution from plastic bottles. Trace amounts of BPA have been detected in bottled water samples. The absorption of BPA was measured with HPLC using a vertical cultivation system with Bulbs of the Allium Cepa plant planted in these plastic bottles with monitored growth. Vertical cultivation was found to have a low level of BPA in the plant cells, making it a safe cultivation method under specific climate conditions. The mean concentration of BPA in vertical cultivation is 0.19 ug/ml (3.8 ng for a 20 uL injection), and the Limit of Quantification (LOQ) is 0.63 ug/ml (12.7 ng for 20 uL injection). While Scanning Electron Microscope (SEM) shows that the concentrations are relatively low in water samples stored at room temperature compared to those exposed to direct sunlight (40°C) and water bottle samples stored at (-4°C), The correlation coefficients were found to be good (0.9992). SEM is used for plastic bottle samples stored at different temperatures. The images identify compound decay and explore the morphology of BPA in manufactured plastic materials. 展开更多
关键词 Vertical Cultivation ALLIUM Bisphenol A Plastic Bottles Scanning Electron Microscope (SEM)
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Anelasticity to plasticity transition in a model two-dimensional amorphous solid
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作者 尚宝双 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期143-147,共5页
Anelasticity, as an intrinsic property of amorphous solids, plays a significant role in understanding their relaxation and deformation mechanism. However, due to the lack of long-range order in amorphous solids, the s... Anelasticity, as an intrinsic property of amorphous solids, plays a significant role in understanding their relaxation and deformation mechanism. However, due to the lack of long-range order in amorphous solids, the structural origin of anelasticity and its distinction from plasticity remain elusive. In this work, using frozen matrix method, we study the transition from anelasticity to plasticity in a two-dimensional model glass. Three distinct mechanical behaviors, namely,elasticity, anelasticity, and plasticity, are identified with control parameters in the amorphous solid. Through the study of finite size effects on these mechanical behaviors, it is revealed that anelasticity can be distinguished from plasticity.Anelasticity serves as an intrinsic bridge connecting the elasticity and plasticity of amorphous solids. Additionally, it is observed that anelastic events are localized, while plastic events are subextensive. The transition from anelasticity to plasticity is found to resemble the entanglement of long-range interactions between element excitations. This study sheds light on the fundamental nature of anelasticity as a key property of element excitations in amorphous solids. 展开更多
关键词 amorphous solid deformation mechanism anelasticity to plasticity transition molecular dynamics simulation
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跨膜emp24转运蛋白家族在人类恶性肿瘤中的研究进展
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作者 李俊蓉(综述) 刘琦 赵寒冰(审校) 《疑难病杂志》 CAS 2024年第9期1140-1143,共4页
跨膜emp24转运蛋白(TMED)家族是一种跨膜蛋白,在早期胚胎发育、器官形成、先天免疫信号传导、细胞增殖等许多方面发挥重要作用。近年来,TMED家族在恶性肿瘤方面的研究备受关注,其异常表达与肿瘤的发生、发展、侵袭、转移及预后都有很大... 跨膜emp24转运蛋白(TMED)家族是一种跨膜蛋白,在早期胚胎发育、器官形成、先天免疫信号传导、细胞增殖等许多方面发挥重要作用。近年来,TMED家族在恶性肿瘤方面的研究备受关注,其异常表达与肿瘤的发生、发展、侵袭、转移及预后都有很大关系。最新研究发现,TMED在不同恶性肿瘤中呈现出不同程度的表达,其中包括乳腺癌、肝癌、卵巢癌、结直肠癌、宫颈癌等,其促进肿瘤发展的机制十分复杂。文章就TMED在恶性肿瘤中的研究现状及作用机制进行综述,为肿瘤的预防和治疗提供新的思路。 展开更多
关键词 恶性肿瘤 跨膜emp24转运蛋白 标志物 早期诊断
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Neurogenesis dynamics in the olfactory bulb:deciphering circuitry organization, function, and adaptive plasticity
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作者 Moawiah M.Naffaa 《Neural Regeneration Research》 SCIE CAS 2025年第6期1565-1581,共17页
Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inh... Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inhibitory interneurons. The generation of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding in circuit remodeling triggered by memory and learning processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ongoing challenge in understanding its network organization and function. Moreover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory information processing. This adaptive process responds to changes in epithelial composition and contributes to the formation of olfactory memories by modulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions remains a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around mitral and tufted cells. This organizational pattern significantly impacts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and memory. Additionally, this organization is further shaped by axon terminals originating from cortical and subcortical regions. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these complex and highly interconnected processes have not been comprehensively studied as a whole. Therefore, this manuscript aims to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These mechanisms are thought to support olfactory learning and memory, potentially through increased complexity and restructuring of neural network structures, as well as the addition of new granule granule cells that aid in olfactory adaptation. Additionally, the manuscript underscores the importance of employing precise methodologies to elucidate the specific roles of adult neurogenesis amidst conflicting data and varying experimental paradigms. Understanding these processes is essential for gaining insights into the complexities of olfactory function and behavior. 展开更多
关键词 network adaptability NEUROGENESIS neuronal communication olfactory bulb olfactory learning olfactory memory synaptic plasticity
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