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Contribution of glial cells to the neuroprotective effects triggered by repetitive magnetic stimulation:a systematic review
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作者 Susana A.Ferreira Nuno Pinto +2 位作者 Inês Serrenho Maria Vaz Pato Graça Baltazar 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第1期116-123,共8页
Repetitive transcranial magnetic stimulation has been increasingly studied in different neurological diseases,and although most studies focus on its effects on neuronal cells,the contribution of nonneuronal cells to t... Repetitive transcranial magnetic stimulation has been increasingly studied in different neurological diseases,and although most studies focus on its effects on neuronal cells,the contribution of nonneuronal cells to the improvement trigge red by repetitive transcranial magnetic stimulation in these diseases has been increasingly suggested.To systematically review the effects of repetitive magnetic stimulation on non-neuronal cells two online databases.Web of Science and PubMed were searched fo r the effects of high-frequency-repetitive transcranial magnetic stimulation,low-frequencyrepetitive transcranial magnetic stimulation,intermittent theta-bu rst stimulation,continuous thetaburst stimulation,or repetitive magnetic stimulation on non-neuronal cells in models of disease and in unlesioned animals or cells.A total of 52 studies were included.The protocol more frequently used was high-frequency-repetitive magnetic stimulation,and in models of disease,most studies report that high-frequency-repetitive magnetic stimulation led to a decrease in astrocyte and mic roglial reactivity,a decrease in the release of pro-inflammatory cyto kines,and an increase of oligodendrocyte proliferation.The trend towards decreased microglial and astrocyte reactivity as well as increased oligodendrocyte proliferation occurred with intermittent theta-burst stimulation and continuous theta-burst stimulation.Few papers analyzed the low-frequency-repetitive transcranial magnetic stimulation protocol,and the parameters evaluated were restricted to the study of astrocyte reactivity and release of pro-inflammatory cytokines,repo rting the absence of effects on these paramete rs.In what concerns the use of magnetic stimulation in unlesioned animals or cells,most articles on all four types of stimulation reported a lack of effects.It is also important to point out that the studies were developed mostly in male rodents,not evaluating possible diffe rential effects of repetitive transcranial magnetic stimulation between sexes.This systematic review supports that thro ugh modulation of glial cells repetitive magnetic stimulation contributes to the neuroprotection or repair in various neurological disease models.Howeve r,it should be noted that there are still few articles focusing on the impact of repetitive magnetic stimulation on non-neuronal cells and most studies did not perform in-depth analyses of the effects,emphasizing the need for more studies in this field. 展开更多
关键词 ASTROCYTE GLIA high-frequency repetitive magnetic stimulation inflammation low-frequency repetitive magnetic stimulation MICROGLIA neurologic disorders OLIGODENDROCYTE repetitive magnetic stimulation theta-burst stimulation
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Evaluation of the coefficient of lateral stress at rest of granular materials under repetitive loading conditions
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作者 Heerym Han Hyunwook Choo Junghee Park 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1709-1721,共13页
Although the internal stress state of soils can be affected by repetitive loading,there are few studies evaluating the lateral stress(or K_(0))of soils under repetitive loading.This study investigates the changes in K... Although the internal stress state of soils can be affected by repetitive loading,there are few studies evaluating the lateral stress(or K_(0))of soils under repetitive loading.This study investigates the changes in K_(0) and directional shear wave velocity(V_(s))in samples of two granular materials with different particle shapes during repetitive loading.A modified oedometer cell equipped with bender elements and a diaphragm transducer was developed to measure the variations in the lateral stress and the shear wave velocity,under repetitive loading on the loading and unloading paths.The study produced the following results:(1)Repetitive loading on the loading path resulted in an increase in the K_(0) of test samples as a function of cyclic loading number(i),and(2)Repetitive loading on the unloading path resulted in a decrease in K_(0) according to i.The shear wave velocity ratio(i.e.V_(s)(HH)/V_(s)(VH),where the first and second letters in parentheses corresponds to the directions of wave propagation and particle motion,respectively,and V and H corresponds to the vertical and horizontal directions,respectively)according to i supports the experimental observations of this study.However,when the tested material was in lightly over-consolidated state,there was an increase in K_(0) during repetitive loading,indicating that it was the initial K_(0),rather than the loading path,which is responsible for the change in K_(0).The power model can capture the variation in the K_(0) of samples according to i.Notably,the K_(0)=1 line acts as the boundary between the increase and decrease in K_(0) under repetitive loading. 展开更多
关键词 Coefficient of lateral stress at rest repetitive loading Granular materials Shear wave velocity Stiffness anisotropy
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Repetitive transcranial magnetic stimulation in Alzheimer’s disease:effects on neural and synaptic rehabilitation
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作者 Yi Ji Chaoyi Yang +7 位作者 Xuerui Pang Yibing Yan Yue Wu Zhi Geng Wenjie Hu Panpan Hu Xingqi Wu Kai Wang 《Neural Regeneration Research》 SCIE CAS 2025年第2期326-342,共17页
Alzheimer’s disease is a neurodegenerative disease resulting from deficits in synaptic transmission and homeostasis.The Alzheimer’s disease brain tends to be hyperexcitable and hypersynchronized,thereby causing neur... Alzheimer’s disease is a neurodegenerative disease resulting from deficits in synaptic transmission and homeostasis.The Alzheimer’s disease brain tends to be hyperexcitable and hypersynchronized,thereby causing neurodegeneration and ultimately disrupting the operational abilities in daily life,leaving patients incapacitated.Repetitive transcranial magnetic stimulation is a cost-effective,neuro-modulatory technique used for multiple neurological conditions.Over the past two decades,it has been widely used to predict cognitive decline;identify pathophysiological markers;promote neuroplasticity;and assess brain excitability,plasticity,and connectivity.It has also been applied to patients with dementia,because it can yield facilitatory effects on cognition and promote brain recovery after a neurological insult.However,its therapeutic effectiveness at the molecular and synaptic levels has not been elucidated because of a limited number of studies.This study aimed to characterize the neurobiological changes following repetitive transcranial magnetic stimulation treatment,evaluate its effects on synaptic plasticity,and identify the associated mechanisms.This review essentially focuses on changes in the pathology,amyloidogenesis,and clearance pathways,given that amyloid deposition is a major hypothesis in the pathogenesis of Alzheimer’s disease.Apoptotic mechanisms associated with repetitive transcranial magnetic stimulation procedures and different pathways mediating gene transcription,which are closely related to the neural regeneration process,are also highlighted.Finally,we discuss the outcomes of animal studies in which neuroplasticity is modulated and assessed at the structural and functional levels by using repetitive transcranial magnetic stimulation,with the aim to highlight future directions for better clinical translations. 展开更多
关键词 Alzheimer’s disease amyloid deposition apoptotic mechanisms BIOMARKER neural regeneration NEURODEGENERATION repetitive transcranial magnetic stimulation synaptic plasticity
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High-frequency repetitive transcranial magnetic stimulation promotes neural stem cell proliferation after ischemic stroke
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作者 Jing Luo Yuan Feng +4 位作者 Zhongqiu Hong Mingyu Yin Haiqing Zheng Liying Zhang Xiquan Hu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第8期1772-1780,共9页
Prolife ration of neural stem cells is crucial for promoting neuronal regeneration and repairing cerebral infarction damage.Transcranial magnetic stimulation(TMS)has recently emerged as a tool for inducing endogenous ... Prolife ration of neural stem cells is crucial for promoting neuronal regeneration and repairing cerebral infarction damage.Transcranial magnetic stimulation(TMS)has recently emerged as a tool for inducing endogenous neural stem cell regeneration,but its underlying mechanisms remain unclea r In this study,we found that repetitive TMS effectively promotes the proliferation of oxygen-glucose deprived neural stem cells.Additionally,repetitive TMS reduced the volume of cerebral infa rction in a rat model of ischemic stro ke caused by middle cerebral artery occlusion,im p roved rat cognitive function,and promoted the proliferation of neural stem cells in the ischemic penumbra.RNA-sequencing found that repetitive TMS activated the Wnt signaling pathway in the ischemic penumbra of rats with cerebral ischemia.Furthermore,PCR analysis revealed that repetitive TMS promoted AKT phosphorylation,leading to an increase in mRNA levels of cell cycle-related proteins such as Cdk2 and Cdk4.This effect was also associated with activation of the glycogen synthase kinase 3β/β-catenin signaling pathway,which ultimately promotes the prolife ration of neural stem cells.Subsequently,we validated the effect of repetitive TMS on AKT phosphorylation.We found that repetitive TMS promoted Ca2+influx into neural stem cells by activating the P2 calcium channel/calmodulin pathway,thereby promoting AKT phosphorylation and activating the glycogen synthase kinase 3β/β-catenin pathway.These findings indicate that repetitive TMS can promote the proliferation of endogenous neural stem cells through a Ca2+influx-dependent phosphorylated AKT/glycogen synthase kinase 3β/β-catenin signaling pathway.This study has produced pioneering res ults on the intrinsic mechanism of repetitive TMS to promote neural function recove ry after ischemic stro ke.These results provide a stro ng scientific foundation for the clinical application of repetitive TMS.Moreover,repetitive TMS treatment may not only be an efficient and potential approach to support neurogenesis for further therapeutic applications,but also provide an effective platform for the expansion of neural stem cells. 展开更多
关键词 AKT/β-catenin signaling brain stimulation Ca2+influx cell proliferation ischemic stroke middle cerebral artery occlusion neural stem cells neurological rehabilitation repetitive transcranial magnetic stimulation
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Exosomes derived from microglia overexpressing miR-124-3p alleviate neuronal endoplasmic reticulum stress damage after repetitive mild traumatic brain injury
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作者 Yan Wang Dai Li +12 位作者 Lan Zhang Zhenyu Yin Zhaoli Han Xintong Ge Meimei Li Jing Zhao Shishuang Zhang Yan Zuo Xiangyang Xiong Han Gao Qiang Liu Fanglian Chen Ping Lei 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第9期2010-2018,共9页
We previously reported that miR-124-3p is markedly upregulated in microglia-derived exosomes following repetitive mild traumatic brain injury.However,its impact on neuronal endoplasmic reticulum stress following repet... We previously reported that miR-124-3p is markedly upregulated in microglia-derived exosomes following repetitive mild traumatic brain injury.However,its impact on neuronal endoplasmic reticulum stress following repetitive mild traumatic brain injury remains unclear.In this study,we first used an HT22 scratch injury model to mimic traumatic brain injury,then co-cultured the HT22 cells with BV2 microglia expressing high levels of miR-124-3p.We found that exosomes containing high levels of miR-124-3p attenuated apoptosis and endoplasmic reticulum stress.Furthermore,luciferase reporter assay analysis confirmed that miR-124-3p bound specifically to the endoplasmic reticulum stress-related protein IRE1α,while an IRE1αfunctional salvage experiment confirmed that miR-124-3p targeted IRE1αand reduced its expression,thereby inhibiting endoplasmic reticulum stress in injured neurons.Finally,we delivered microglia-derived exosomes containing miR-124-3p intranasally to a mouse model of repetitive mild traumatic brain injury and found that endoplasmic reticulum stress and apoptosis levels in hippocampal neurons were significantly reduced.These findings suggest that,after repetitive mild traumatic brain injury,miR-124-3 can be transferred from microglia-derived exosomes to injured neurons,where it exerts a neuroprotective effect by inhibiting endoplasmic reticulum stress.Therefore,microglia-derived exosomes containing miR-124-3p may represent a novel therapeutic strategy for repetitive mild traumatic brain injury. 展开更多
关键词 apoptosis C/EBP homologous protein endoplasmic reticulum stress EXOSOME inositol-requiring enzyme MICROGLIA miR-124-3p neuron repetitive mild traumatic brain injury X-box binding protein 1
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Analyzing the Combination Effects of Repetitive Transcranial Magnetic Stimulation and Motor Control Training on Balance Function and Gait in Patients with Stroke-Induced Hemiplegia
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作者 Xiaoqing Ma Zhen Ma +2 位作者 Ye Xu Meng Han Hui Yan 《Proceedings of Anticancer Research》 2024年第1期54-60,共7页
Objective:To analyze the effects of repetitive transcranial magnetic stimulation combined with motor control training on the treatment of stroke-induced hemiplegia,specifically focusing on the impact on patients’bala... Objective:To analyze the effects of repetitive transcranial magnetic stimulation combined with motor control training on the treatment of stroke-induced hemiplegia,specifically focusing on the impact on patients’balance function and gait.Methods:Fifty-two cases of hemiplegic stroke patients were randomly divided into two groups,26 in the control group and 26 in the observation group,using computer-generated random grouping.All participants underwent conventional treatment and rehabilitation training.In addition to these,the control group received repetitive transcranial magnetic pseudo-stimulation therapy+motor control training,while the observation group received repetitive transcranial magnetic stimulation therapy+motor control training.The balance function and gait parameters of both groups were compared before and after the interventions and assessed the satisfaction of the interventions in both groups.Results:Before the invention,there were no significant differences in balance function scores and each gait parameter between the two groups(P>0.05).However,after the intervention,the observation group showed higher balance function scores compared to the control group(P<0.05).The observation group also exhibited higher step speed and step frequency,longer step length,and a higher overall satisfaction level with the intervention compared to the control group(P<0.05).Conclusion:The combination of repetitive transcranial magnetic stimulation and motor control training in the treatment of stroke-induced hemiplegia has demonstrated positive effects.It not only improves the patient’s balance function and gait but also contributes to overall physical rehabilitation. 展开更多
关键词 Stroke-induced hemiplegia repetitive transcranial magnetic stimulation Motor control training Balance function GAIT
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Study on the Effect of Repetitive Peripheral Magnetic Stimulation Combined with Conventional Rehabilitation Measures on Shoulder Dysfunction in Early Stroke
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作者 Hui Yan Mingmei Ding +2 位作者 Ye Xu Zhen Ma Xiaoqing Ma 《Journal of Clinical and Nursing Research》 2024年第2期44-49,共6页
Objective:To study the effect of repetitive peripheral magnetic stimulation(rPMS)combined with conventional rehabilitation measures on shoulder dysfunction in early stroke.Methods:60 patients with shoulder dysfunction... Objective:To study the effect of repetitive peripheral magnetic stimulation(rPMS)combined with conventional rehabilitation measures on shoulder dysfunction in early stroke.Methods:60 patients with shoulder dysfunction in early stroke were selected,and all of them were admitted to our hospital from August 2021 to August 2023.The patients were randomly grouped into a control group(conventional rehabilitation measures intervention,30 cases)and an intervention group(rPMS and conventional rehabilitation measures intervention,30 cases)according to the lottery method.The pain scores,shoulder mobility,and motor function scores of the two groups were compared.Results:The pain score was lower in the intervention group,and the shoulder mobility and motor function scores were higher in the intervention group(P<0.05)as compared to that of the control group.Conclusion:The effect of combining rPMS and conventional rehabilitation measures in treating shoulder dysfunction in early stroke was remarkable and should be popularized. 展开更多
关键词 repetitive peripheral magnetic stimulation Conventional rehabilitation measures Early stroke Shoulder joint function
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Repetitive transcranial magnetic stimulation promotes neurological functional recovery in rats with traumatic brain injury by upregulating synaptic plasticity-related proteins 被引量:3
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作者 Fang-Fang Qian You-Hua He +3 位作者 Xiao-Hui Du Hua-Xiang Lu Ren-Hong He Jian-Zhong Fan 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第2期368-374,共7页
Studies have shown that repetitive transcra nial magnetic stimulation(rTMS)can enhance synaptic plasticity and improve neurological dysfunction.Howeve r,the mechanism through which rTMS can improve moderate traumatic ... Studies have shown that repetitive transcra nial magnetic stimulation(rTMS)can enhance synaptic plasticity and improve neurological dysfunction.Howeve r,the mechanism through which rTMS can improve moderate traumatic brain injury remains poorly understood.In this study,we established rat models of moderate traumatic brain injury using Feeney's weight-dropping method and treated them using rTMS.To help determine the mechanism of action,we measured levels of seve ral impo rtant brain activity-related proteins and their mRNA.On the injured side of the brain,we found that rTMS increased the protein levels and mRNA expression of brain-derived neurotrophic factor,tropomyosin receptor kinase B,N-methyl-D-aspartic acid receptor 1,and phosphorylated cAMP response element binding protein,which are closely associated with the occurrence of long-term potentiation.rTMS also partially reve rsed the loss of synaptophysin after injury and promoted the remodeling of synaptic ultrastructure.These findings suggest that upregulation of synaptic plasticity-related protein expression is the mechanism through which rTMS promotes neurological function recovery after moderate traumatic brain injury. 展开更多
关键词 brain-derived neurotrophic factor moderate traumatic brain injury neurological dysfunction neurological improvement N-methyl-D-aspartic acid receptor repetitive transcranial magnetic stimulation synaptic plasticity SYNAPTOPHYSIN traumatic brain injury TRKB
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Quantitative proteomic and phosphoproteomic analyses of the hippocampus reveal the involvement of NMDAR1 signaling in repetitive mild traumatic brain injury 被引量:1
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作者 Zhicheng Tian Zixuan Cao +9 位作者 Erwan Yang Juan Li Dan Liao Fei Wang Taozhi Wang Zhuoyuan Zhang Haofuzi Zhang Xiaofan Jiang Xin Li Peng Luo 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第12期2711-2719,共9页
The cumulative damage caused by repetitive mild traumatic brain injury can cause long-term neurodegeneration leading to cognitive impairment.This cognitive impairment is thought to result specifically from damage to t... The cumulative damage caused by repetitive mild traumatic brain injury can cause long-term neurodegeneration leading to cognitive impairment.This cognitive impairment is thought to result specifically from damage to the hippocampus.In this study,we detected cognitive impairment in mice 6 weeks after repetitive mild traumatic brain injury using the novel object recognition test and the Morris water maze test.Immunofluorescence staining showed that p-tau expression was increased in the hippocampus after repetitive mild traumatic brain injury.Golgi staining showed a significant decrease in the total density of neuronal dendritic spines in the hippocampus,as well as in the density of mature dendritic spines.To investigate the specific molecular mechanisms underlying cognitive impairment due to hippocampal damage,we performed proteomic and phosphoproteomic analyses of the hippocampus with and without repetitive mild traumatic brain injury.The differentially expressed proteins were mainly enriched in inflammation,immunity,and coagulation,suggesting that non-neuronal cells are involved in the pathological changes that occur in the hippocampus in the chronic stage after repetitive mild traumatic brain injury.In contrast,differentially expressed phosphorylated proteins were mainly enriched in pathways related to neuronal function and structure,which is more consistent with neurodegeneration.We identified N-methyl-D-aspartate receptor 1 as a hub molecule involved in the response to repetitive mild traumatic brain injury,and western blotting showed that,while N-methyl-D-aspartate receptor 1 expression was not altered in the hippocampus after repetitive mild traumatic brain injury,its phosphorylation level was significantly increased,which is consistent with the omics results.Administration of GRP78608,an N-methyl-D-aspartate receptor 1 antagonist,to the hippocampus markedly improved repetitive mild traumatic brain injury-induced cognitive impairment.In conclusion,our findings suggest that N-methyl-D-aspartate receptor 1 signaling in the hippocampus is involved in cognitive impairment in the chronic stage after repetitive mild traumatic brain injury and may be a potential target for intervention and treatment. 展开更多
关键词 cognitive impairment Grin1 HIPPOCAMPUS learning memory N-METHYL-D-ASPARTATE N-methyl-D-aspartate receptor 1 phosphoproteomic PROTEOMIC repetitive mild traumatic brain injury(rmTBI) secondary injury
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A Fractional Order Fast Repetitive Control Paradigm of Vienna Rectifier for Power Quality Improvement
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作者 Sue Wang Xintao Luo +3 位作者 Saleem Riaz Haider Zaman Chaohong Zhou Pengfei Hao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第2期1159-1176,共18页
Due to attractive features,including high efficiency,low device stress,and ability to boost voltage,a Vienna rectifier is commonly employed as a battery charger in an electric vehicle(EV).However,the 6k±1 harmoni... Due to attractive features,including high efficiency,low device stress,and ability to boost voltage,a Vienna rectifier is commonly employed as a battery charger in an electric vehicle(EV).However,the 6k±1 harmonics in the acside current of the Vienna rectifier deteriorate theTHDof the ac current,thus lowering the power factor.Therefore,the current closed-loop for suppressing 6k±1 harmonics is essential tomeet the desired total harmonic distortion(THD).Fast repetitive control(FRC)is generally adopted;however,the deviation of power grid frequency causes delay link in the six frequency fast repetitive control to become non-integer and the tracking performance to deteriorate.This paper presents the detailed parameter design and calculation of fractional order fast repetitive controller(FOFRC)for the non-integer delay link.The finite polynomial approximates the non-integer delay link through the Lagrange interpolation method.By comparing the frequency characteristics of traditional repetitive control,the effectiveness of the FOFRC strategy is verified.Finally,simulation and experiment validate the steadystate performance and harmonics suppression ability of FOFRC. 展开更多
关键词 Vienna rectifier fast repetitive control fractional order performance analysis
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Repetitive transcranial magnetic stimulation combined with olanzapine and amisulpride for treatment-refractory schizophrenia
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作者 Jin-Ling Liu Zhi-Mei Tan Shu-Jie Jiao 《World Journal of Psychiatry》 SCIE 2023年第7期453-460,共8页
BACKGROUND Treatment-refractory schizophrenia(TRS),accounting for approximately 30%of all schizophrenia cases,has poor treatment response and prognosis despite treatment with antipsychotic drugs.AIM To analyze the the... BACKGROUND Treatment-refractory schizophrenia(TRS),accounting for approximately 30%of all schizophrenia cases,has poor treatment response and prognosis despite treatment with antipsychotic drugs.AIM To analyze the therapeutic effectiveness of repetitive transcranial magnetic stimulation(rTMS)combined with olanzapine(OLZ)and amisulpride(AMI)for TRS and its influence on the patient’s cognitive function.METHODS This study enrolled 114 TRS patients who received treatment at the First Affiliated Hospital of Zhengzhou University between July 2019 and July 2022.In addition to the basic OLZ+AMI therapy,54 cases of the control group(Con group)received modified electroconvulsive therapy,while 60 cases of the research group(Res group)received rTMS.Data on therapeutic effectiveness,safety(incidence of drowsiness,headache,nausea,vomiting,or memory impairment),Positive and Negative Symptom Scale,Montreal Cognitive Assessment Scale,and Schizophrenia Quality of Life Scale were collected from both cohorts for comparative analyses.RESULTS The Res group elicited a higher overall response rate and better safety profile when compared with the Con group.Additionally,a significant reduction was observed in the post-treatment Positive and Negative Symptom Scale and Schizophrenia Quality of Life Scale scores of the Res group,presenting lower scores than those of the Con group.Furthermore,a significant increase in the Montreal Cognitive Assessment Scale score was reported in the Res group,with higher scores than those of the Con group.CONCLUSION The treatment of TRS with rTMS and OLZ+AMI is effective and safe.Moreover,it can alleviate the patients’mental symptoms,improve their cognitive function and quality of life,and has a high clinical application value. 展开更多
关键词 repetitive transcranial magnetic stimulation OLANZAPINE AMISULPRIDE Treatment-refractory schizophrenia Therapeutic effectiveness Cognitive function
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Influence of acceleration stage electrode voltage on the performance of double-stage Hall effect thruster with adjustable zero magnetic point
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作者 陈龙 高维富 +5 位作者 崔作君 段萍 许雪松 阚子晨 檀聪琦 陈俊宇 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第6期60-69,共10页
The configuration of electrode voltage and zero magnetic point position has a significant impact on the performance of the double-stage Hall effect thruster. A 2D-3V model is established based on the two-magnetic peak... The configuration of electrode voltage and zero magnetic point position has a significant impact on the performance of the double-stage Hall effect thruster. A 2D-3V model is established based on the two-magnetic peak type double-stage Hall thruster configuration, and a particle-in-cell simulation is carried out to investigate the influences of both acceleration electrode voltage value and zero magnetic point position on the thruster discharge characteristics and performances.The results indicate that increasing the acceleration voltage leads to a larger potential drop in the acceleration stage, allowing ions to gain higher energy, while electrons are easily absorbed by the intermediate electrode, resulting in a decrease in the anode current and ionization rate. When the acceleration voltage reaches 500 V, the thrust and efficiency are maximized, resulting in a 15%increase in efficiency. After the acceleration voltage exceeds 500 V, a potential barrier forms within the channel, leading to a decrease in thruster efficiency. Further study shows that as the second zero magnetic point moves towards the outlet of the channel, more electrons easily traverse the zero magnetic field region, participating in the ionization. The increase in the ionization rate leads to a gradual enhancement in both thrust and efficiency. 展开更多
关键词 Hall thruster particle-in-cell simulation intermediate electrode zero magnetic point
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A Cross-Sectional Study on the Impact of Operation Triple Zero (OTZ) Program on Viral Load Suppression amongst Members of the Adolescent Club in 68 Nigerian Army Reference Hospital Yaba Lagos, Nigeria
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作者 Nkechinyere Harrison Ismail Lawal +7 位作者 Yakubu Adamu Kehinde Aribisala Adegbenga Olarinoye Uzoamaka Agbaim Funmilayo Owolabi Dooshima Okonkwo Laura Chittenden Nathan Okeji 《World Journal of AIDS》 2024年第2期35-44,共10页
Background: In Nigeria, adolescents and young people (AYP) aged 10 - 24, comprise 22.3% of the population and with HIV prevalence of 3.5%. The AYP living with HIV enrolled at the 68 NARHY, Lagos reflects the national ... Background: In Nigeria, adolescents and young people (AYP) aged 10 - 24, comprise 22.3% of the population and with HIV prevalence of 3.5%. The AYP living with HIV enrolled at the 68 NARHY, Lagos reflects the national challenges with poor viral suppression. The OTZ program aligns with the UNAIDS 95-95-95 goals. It seeks to empower AYPLHIV to be in charge of their treatment and commit to triple zero outcomeszero missed appointments, zero missed drugs, and zero viral loads. The purpose of the study was to assess the impact of the OTZ program on viral load suppression among members of the adolescent club in 68 NARHY, Lagos. Method: A cross-sectional retrospective study to evaluate the impact of the OTZ program on the viral load of 53 AYP enrolled in the OTZ program between March 2019 to December 2019 was analyzed. The Percentage of viral load suppression before enrollment compared with 6 and 12 months after enrollment into the OTZ program. The AYP is grouped into 10 - 14, 15 - 19, and 20 - 24 years. Activities conducted were peer driven monthly meetings with the AYP during which the adolescents interacted on issues relating to improving their treatment outcomes, healthcare workers reviewed their clinical status, viral load result, provider peer counseling, and caregivers engagement to support adherence to medication and ARV refills. Results: Before OTZ, 81% aged 10 - 14 years, 75% aged 15 - 19 years, and 25% aged 20 - 24 years were virally suppressed (VL less than 1000 copies/ml). Six months after enrollment, 94% were virally suppressed95% aged 10 - 14 years, 96% aged 15 - 19 years, and 66% aged 20-24 years. Twelve months after enrollment, 96% of AYP were virally suppressed100% aged 10-14 years, 93% aged 15 - 19 years, and 100% aged 20 - 24 years. Males viral load (VL) suppression improved from 79% to 96% and 92%, while females VL suppression improved from 69% to 93% and 100% at 6 and 12 months respectively. Conclusion: The OTZ activities contributed to improved viral load suppression in the AYP of the facility. 展开更多
关键词 Impact Operation Triple zero ADOLESCENT Viral Load NIGERIA
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Development of a high-repetition-rate lumped-inductance kicker magnet prototype for the beam switchyard of SHINE
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作者 Yong-Fang Liu Rui-Ping Wang +6 位作者 Jin Tong Bo Zhang Si Chen Qi-Bing Yuan Hai-Xiao Deng Ming Gu Bo Liu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期20-31,共12页
The Shanghai high-repetition-rate X-ray free-electron laser and extreme light facility(SHINE)operates at a maximum repetition rate of 1 MHz.Kicker magnets are key components that distribute electron bunches into three... The Shanghai high-repetition-rate X-ray free-electron laser and extreme light facility(SHINE)operates at a maximum repetition rate of 1 MHz.Kicker magnets are key components that distribute electron bunches into three different undulator lines in a bunch-by-bunch mode.The kicker field width must be less than the time interval between bunches.A lumpedinductance kicker prototype was developed using a vacuum chamber with a single-turn coil.The full magnetic field strength was 0.005 T.This paper presents the requirements,design considerations,design parameters,magnetic field calculations,and measurements of the kicker magnets.The relevant experimental results are also presented.The pulse width of the magnetic field was approximately 600 ns,and the maximum operation repetition rate was 1 MHz.The developed kicker satisfies the requirements for the SHINE project.Finally,numerous recommendations for the future optimization of kicker magnets are provided. 展开更多
关键词 X-ray free-electron laser Kicker magnet Beam switchyard High repetition rate Ni-Zn ferrites
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Research on Data Tampering Prevention Method for ATC Network Based on Zero Trust
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作者 Xiaoyan Zhu Ruchun Jia +1 位作者 Tingrui Zhang Song Yao 《Computers, Materials & Continua》 SCIE EI 2024年第3期4363-4377,共15页
The traditional air traffic control information sharing data has weak security characteristics of personal privacy data and poor effect,which is easy to leads to the problem that the data is usurped.Starting from the ... The traditional air traffic control information sharing data has weak security characteristics of personal privacy data and poor effect,which is easy to leads to the problem that the data is usurped.Starting from the application of the ATC(automatic train control)network,this paper focuses on the zero trust and zero trust access strategy and the tamper-proof method of information-sharing network data.Through the improvement of ATC’s zero trust physical layer authentication and network data distributed feature differentiation calculation,this paper reconstructs the personal privacy scope authentication structure and designs a tamper-proof method of ATC’s information sharing on the Internet.From the single management authority to the unified management of data units,the systematic algorithm improvement of shared network data tamper prevention method is realized,and RDTP(Reliable Data Transfer Protocol)is selected in the network data of information sharing resources to realize the effectiveness of tamper prevention of air traffic control data during transmission.The results show that this method can reasonably avoid the tampering of information sharing on the Internet,maintain the security factors of air traffic control information sharing on the Internet,and the Central Processing Unit(CPU)utilization rate is only 4.64%,which effectively increases the performance of air traffic control data comprehensive security protection system. 展开更多
关键词 zero trust access policy air traffic information sharing network privacy data tam-per-proof certification features
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Algorithm for Visualization of Zero Divisor Graphs of the Ring ℤn Using MAPLE Coding
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作者 Nasir Ali 《Open Journal of Discrete Mathematics》 2024年第1期1-8,共8页
This research investigates the comparative efficacy of generating zero divisor graphs (ZDGs) of the ring of integers ℤ<sub>n</sub> modulo n using MAPLE algorithm. Zero divisor graphs, pivotal in the study ... This research investigates the comparative efficacy of generating zero divisor graphs (ZDGs) of the ring of integers ℤ<sub>n</sub> modulo n using MAPLE algorithm. Zero divisor graphs, pivotal in the study of ring theory, depict relationships between elements of a ring that multiply to zero. The paper explores the development and implementation of algorithms in MAPLE for constructing these ZDGs. The comparative study aims to discern the strengths, limitations, and computational efficiency of different MAPLE algorithms for creating zero divisor graphs offering insights for mathematicians, researchers, and computational enthusiasts involved in ring theory and mathematical computations. 展开更多
关键词 zero Divisor Graph Ring Theory Maple Algorithm n Modulo n Graph Theory Mathematical Computing
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From Standard Policy-Based Zero Trust to Absolute Zero Trust (AZT): A Quantum Leap to Q-Day Security
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作者 Fazal Raheman 《Journal of Computer and Communications》 2024年第3期252-282,共31页
Cybercrime is projected to cost a whopping $23.8 Trillion by 2027. This is essentially because there’s no computer network that’s not vulnerable. Fool-proof cybersecurity of personal data in a connected computer is ... Cybercrime is projected to cost a whopping $23.8 Trillion by 2027. This is essentially because there’s no computer network that’s not vulnerable. Fool-proof cybersecurity of personal data in a connected computer is considered practically impossible. The advent of quantum computers (QC) will worsen cybersecurity. QC will be a boon for data-intensive industries by drastically reducing the computing time from years to minutes. But QC will render our current cryptography vulnerable to quantum attacks, breaking nearly all modern cryptographic systems. Before QCs with sufficient qubits arrive, we must be ready with quantum-safe strategies to protect our ICT infrastructures. Post-quantum cryptography (PQC) is being aggressively pursued worldwide as a defence from the potential Q-day threat. NIST (National Institute of Standards and Technology), in a rigorous process, tested 82 PQC schemes, 80 of which failed after the final round in 2022. Recently the remaining two PQCs were also cracked by a Swedish and a French team of cryptographers, placing NIST’s PQC standardization process in serious jeopardy. With all the NIST-evaluated PQCs failing, there’s an urgent need to explore alternate strategies. Although cybersecurity heavily relies on cryptography, recent evidence indicates that it can indeed transcend beyond encryption using Zero Vulnerability Computing (ZVC) technology. ZVC is an encryption-agnostic absolute zero trust (AZT) approach that can potentially render computers quantum resistant by banning all third-party permissions, a root cause of most vulnerabilities. Unachievable in legacy systems, AZT is pursued by an experienced consortium of European partners to build compact, solid-state devices that are robust, resilient, energy-efficient, and with zero attack surface, rendering them resistant to malware and future Q-Day threats. 展开更多
关键词 CYBERSECURITY Quantum Computers Post Quantum Cryptography Q-Day zero Trust
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虚拟桌面与零客户端在实验室管理中的研究应用——VMware Horizon View与Dell Wyse Zero Client的融合研究
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作者 吴磊 《佳木斯大学学报(自然科学版)》 CAS 2024年第1期125-128,共4页
我校计算机实验室至今仍在使用2006年开发的机房计费管理系统,此系统的刷卡终端安装于实验室外,常年运行在恶劣的户外环境中,因此故障频发,无法长时间正常运行。面对上述问题,我校教学环境部利用当前已趋于成熟的虚拟桌面技术,让机房计... 我校计算机实验室至今仍在使用2006年开发的机房计费管理系统,此系统的刷卡终端安装于实验室外,常年运行在恶劣的户外环境中,因此故障频发,无法长时间正常运行。面对上述问题,我校教学环境部利用当前已趋于成熟的虚拟桌面技术,让机房计费管理系统的刷卡终端能够稳定地运行在恶劣的户外环境中,并且能够便利地对其进行管理和维护。 展开更多
关键词 计算机实验室 刷卡终端 虚拟桌面 零客户端
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基于强化学习与Zero-DCE的图像增强方法
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作者 王鹏飞 单新文 +1 位作者 奚梦婷 魏晓龙 《电工技术》 2024年第1期47-51,共5页
在深度学习技术不断演进的背景下,图像增强技术在图像处理领域备受瞩目。尽管传统的处理方法在改善图像质量方面有所成就,但对于高动态范围、高噪声、低对比度等复杂场景的图像处理需求,其效果通常难以令人满意。采用了创新性的图像增... 在深度学习技术不断演进的背景下,图像增强技术在图像处理领域备受瞩目。尽管传统的处理方法在改善图像质量方面有所成就,但对于高动态范围、高噪声、低对比度等复杂场景的图像处理需求,其效果通常难以令人满意。采用了创新性的图像增强方法,将图像分解为照明和反射两部分,以实现更为出色的增强效果。综合运用Retinex、Zero-DCE和强化学习技术,提升了图像质量和可视性,在处理复杂场景中展现了显著的效果。通过强化学习和组合损失函数,使得图像增强效果更显著。基于Retinex理论的实现方式进一步加强了整体算法的性能。此外,结合Zero-DCE的方法,通过深度曲线估计照明和反射两部分,有效区分了不同场景的图像增强需求。 展开更多
关键词 强化学习 微光增强 zero-DCE RETINEX
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Repetitive代数的导出等价 被引量:1
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作者 陈清华 《数学进展》 CSCD 北大核心 2008年第2期189-196,共8页
若代数A和B导出等价,则它们的Repetitive代数■和■也是导出等价,从而是稳定等价.这样利用更直接的代数方法完全回答了H.Asashiba提出的问题,并推广了Rickard,杜先能,Tachikawa-Wakamatsu等人的相应结果.进而,把以上结果推广到上有界复... 若代数A和B导出等价,则它们的Repetitive代数■和■也是导出等价,从而是稳定等价.这样利用更直接的代数方法完全回答了H.Asashiba提出的问题,并推广了Rickard,杜先能,Tachikawa-Wakamatsu等人的相应结果.进而,把以上结果推广到上有界复形的导出范畴的对称recollement的情形. 展开更多
关键词 repetitive代数 导出等价 稳定等价 (对称)recollement
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