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Aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders:progress of experimental models based on disease pathogenesis
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作者 Li Xu Huiming Xu Changyong Tang 《Neural Regeneration Research》 SCIE CAS 2025年第2期354-365,共12页
Neuromyelitis optica spectrum disorders are neuroinflammatory demyelinating disorders that lead to permanent visual loss and motor dysfunction.To date,no effective treatment exists as the exact causative mechanism rem... Neuromyelitis optica spectrum disorders are neuroinflammatory demyelinating disorders that lead to permanent visual loss and motor dysfunction.To date,no effective treatment exists as the exact causative mechanism remains unknown.Therefore,experimental models of neuromyelitis optica spectrum disorders are essential for exploring its pathogenesis and in screening for therapeutic targets.Since most patients with neuromyelitis optica spectrum disorders are seropositive for IgG autoantibodies against aquaporin-4,which is highly expressed on the membrane of astrocyte endfeet,most current experimental models are based on aquaporin-4-IgG that initially targets astrocytes.These experimental models have successfully simulated many pathological features of neuromyelitis optica spectrum disorders,such as aquaporin-4 loss,astrocytopathy,granulocyte and macrophage infiltration,complement activation,demyelination,and neuronal loss;however,they do not fully capture the pathological process of human neuromyelitis optica spectrum disorders.In this review,we summarize the currently known pathogenic mechanisms and the development of associated experimental models in vitro,ex vivo,and in vivo for neuromyelitis optica spectrum disorders,suggest potential pathogenic mechanisms for further investigation,and provide guidance on experimental model choices.In addition,this review summarizes the latest information on pathologies and therapies for neuromyelitis optica spectrum disorders based on experimental models of aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders,offering further therapeutic targets and a theoretical basis for clinical trials. 展开更多
关键词 AQUAPORIN-4 experimental model neuromyelitis optica spectrum disorder PATHOGENESIS
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The Impairment Attention Capture by Topological Change in Children With Autism Spectrum Disorder
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作者 XU Hui-Lin XI Huan-Jun +4 位作者 DUAN Tao LI Jing LI Dan-Dan WANG Kai ZHU Chun-Yan 《生物化学与生物物理进展》 北大核心 2025年第1期223-232,共10页
Objective Autism spectrum disorder(ASD)is a neurodevelopmental condition characterized by difficulties with communication and social interaction,restricted and repetitive behaviors.Previous studies have indicated that... Objective Autism spectrum disorder(ASD)is a neurodevelopmental condition characterized by difficulties with communication and social interaction,restricted and repetitive behaviors.Previous studies have indicated that individuals with ASD exhibit early and lifelong attention deficits,which are closely related to the core symptoms of ASD.Basic visual attention processes may provide a critical foundation for their social communication and interaction abilities.Therefore,this study explores the behavior of children with ASD in capturing attention to changes in topological properties.Methods Our study recruited twenty-seven ASD children diagnosed by professional clinicians according to DSM-5 and twenty-eight typically developing(TD)age-matched controls.In an attention capture task,we recorded the saccadic behaviors of children with ASD and TD in response to topological change(TC)and non-topological change(nTC)stimuli.Saccadic reaction time(SRT),visual search time(VS),and first fixation dwell time(FFDT)were used as indicators of attentional bias.Pearson correlation tests between the clinical assessment scales and attentional bias were conducted.Results This study found that TD children had significantly faster SRT(P<0.05)and VS(P<0.05)for the TC stimuli compared to the nTC stimuli,while the children with ASD did not exhibit significant differences in either measure(P>0.05).Additionally,ASD children demonstrated significantly less attention towards the TC targets(measured by FFDT),in comparison to TD children(P<0.05).Furthermore,ASD children exhibited a significant negative linear correlation between their attentional bias(measured by VS)and their scores on the compulsive subscale(P<0.05).Conclusion The results suggest that children with ASD have difficulty shifting their attention to objects with topological changes during change detection.This atypical attention may affect the child’s cognitive and behavioral development,thereby impacting their social communication and interaction.In sum,our findings indicate that difficulties in attentional capture by TC may be a key feature of ASD. 展开更多
关键词 ATTENTION autism spectrum disorder perceptual object topological perception
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Resource Optimization in Elastic Optical Networks Using Threshold-Based Routing and Fragmentation-Aware Spectrum Allocation
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作者 Kamagaté Beman Hamidja Kanga Koffi +2 位作者 Coulibaly Kpinan Tiekoura Konaté Adama Michel Babri 《Open Journal of Applied Sciences》 2025年第1期168-186,共19页
This paper proposes an efficient strategy for resource utilization in Elastic Optical Networks (EONs) to minimize spectrum fragmentation and reduce connection blocking probability during Routing and Spectrum Allocatio... This paper proposes an efficient strategy for resource utilization in Elastic Optical Networks (EONs) to minimize spectrum fragmentation and reduce connection blocking probability during Routing and Spectrum Allocation (RSA). The proposed method, Dynamic Threshold-Based Routing and Spectrum Allocation with Fragmentation Awareness (DT-RSAF), integrates rerouting and spectrum defragmentation as needed. By leveraging Yen’s shortest path algorithm, DT-RSAF enhances resource utilization while ensuring improved service continuity. A dynamic threshold mechanism enables the algorithm to adapt to varying network conditions, while its fragmentation awareness effectively mitigates spectrum fragmentation. Simulation results on NSFNET and COST 239 topologies demonstrate that DT-RSAF significantly outperforms methods such as K-Shortest Path Routing and Spectrum Allocation (KSP-RSA), Load Balanced and Fragmentation-Aware (LBFA), and the Invasive Weed Optimization-based RSA (IWO-RSA). Under heavy traffic, DT-RSAF reduces the blocking probability by up to 15% and achieves lower Bandwidth Fragmentation Ratios (BFR), ranging from 74% to 75%, compared to 77% - 80% for KSP-RSA, 75% - 77% for LBFA, and approximately 76% for IWO-RSA. DT-RSAF also demonstrated reasonable computation times compared to KSP-RSA, LBFA, and IWO-RSA. On a small-sized network, its computation time was 8710 times faster than that of Integer Linear Programming (ILP) on the same network topology. Additionally, it achieved a similar execution time to LBFA and outperformed IWO-RSA in terms of efficiency. These results highlight DT-RSAF’s capability to maintain large contiguous frequency blocks, making it highly effective for accommodating high-bandwidth requests in EONs while maintaining reasonable execution times. 展开更多
关键词 Elastic Optical Networks (EONs) spectrum Fragmentation Routing and spectrum Allocation (RSA) Connection Rerouting HEURISTIC
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Microbial Spectrum and Antibiotic Sensitivity Study of Postoperative Infections in Traumatology: Discussion on Optimizing Usage Strategies
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作者 Minxia Liao Runxiu Xia# Bin Han# 《Advances in Microbiology》 2025年第2期112-125,共14页
Objective: With the increasing volume of trauma surgery, postoperative infections have garnered significant attention, as they not only affect patient outcomes but also raise healthcare costs and the risk of bacterial... Objective: With the increasing volume of trauma surgery, postoperative infections have garnered significant attention, as they not only affect patient outcomes but also raise healthcare costs and the risk of bacterial resistance. This study aims to analyze the microbial spectrum and antibiotic sensitivity of patients with postoperative infections in trauma surgery, providing a basis for clinical treatment and optimizing antibiotic usage strategies in this context. Methods: A retrospective analysis was conducted on patients with traumatic infections who were hospitalized in the departments of spine surgery, upper limb surgery, and lower limb surgery from January 2022 to December 2024. Bacterial culture-positive specimens were analyzed for bacterial species and antibiotic sensitivity. Results: A total of 804 traumatic infection specimens were submitted for testing, including 538 male patients (ages 2 - 95 years) and 266 female patients (ages 4 - 94 years). Among these, 267 cases showed positive culture results, with 172 males (ages 2 - 93 years) and 95 females (ages 4 - 94 years). A total of 153 strains of Gram-negative (G−) bacteria and 114 strains of Gram-positive (G+) bacteria were identified. Among G− bacteria, Escherichia coli was the most frequently isolated (40 strains), followed by Pseudomonas aeruginosa (28 strains) and Enterobacter cloacae (28 strains). Among G+ bacteria, Staphylococcus aureus was the most prevalent (75 strains), followed by Enterococcus faecalis (15 strains) and Streptococcus pyogenes (8 strains). Antibiotic sensitivity testing revealed that the resistance rate of Staphylococcus aureus to penicillin was as high as 93.33%, while the resistance rate of Escherichia coli to trimethoprim-sulfamethoxazole was 57.5%. Conclusion: The main pathogens responsible for postoperative infections in traumatology are Escherichia coli and Staphylococcus aureus, with significant antibiotic resistance. In clinical treatment, antibiotics should be selected rationally based on bacterial spectrum and resistance patterns to improve treatment efficacy. 展开更多
关键词 Traumatic Infection Microbial spectrum Antibiotic Sensitivity Escherichia Coli Staphylococcus Aureus
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Advances in the treatment of autism spectrum disorder:Wharton jelly mesenchymal stem cell transplantation
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作者 Serdar Kabatas ErdinçCivelek +3 位作者 Eyüp Can Savrunlu Umut Karaaslan Özlem Yıldız Erdal Karaöz 《World Journal of Methodology》 2025年第1期72-79,共8页
BACKGROUND Autism spectrum disorder(ASD)is a complex neurodevelopmental disorder with multifaceted origins.In recent studies,neuroinflammation and immune dysregulation have come to the forefront in its pathogenesis.Th... BACKGROUND Autism spectrum disorder(ASD)is a complex neurodevelopmental disorder with multifaceted origins.In recent studies,neuroinflammation and immune dysregulation have come to the forefront in its pathogenesis.There are studies suggesting that stem cell therapy may be effective in the treatment of ASD.AIM To evolve the landscape of ASD treatment,focusing on the potential benefits and safety of stem cell transplantation.METHODS A detailed case report is presented,displaying the positive outcomes observed in a child who underwent intrathecal and intravenous Wharton’s jelly-derived mesenchymal stem cells(WJ-MSCs)transplantation combined with neurorehabilitation.RESULTS The study demonstrates a significant improvement in the child’s functional outcomes(Childhood Autism Rating Scale,Denver 2 Developmental Screening Test),especially in language and gross motor skills.No serious side effects were encountered during the 2-year follow-up.CONCLUSION The findings support the safety and effectiveness of WJ-MSC transplantation in managing ASD. 展开更多
关键词 Autism spectrum disorder NEUROREHABILITATION Stem cell transplantation Wharton jelly mesenchymal stem cells INFLAMMATION
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Generating Social Interactions with Adolescents with Autism Spectrum Disorder, through a Gesture Imitation Game Led by a Humanoid Robot, in Collaboration with a Human Educator
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作者 Linda Vallée Malik Koné Olivier Asseu 《Open Journal of Psychiatry》 2025年第1期55-71,共17页
This article describes a pilot study aiming at generating social interactions between a humanoid robot and adolescents with autism spectrum disorder (ASD), through the practice of a gesture imitation game. The partici... This article describes a pilot study aiming at generating social interactions between a humanoid robot and adolescents with autism spectrum disorder (ASD), through the practice of a gesture imitation game. The participants were a 17-year-old young lady with ASD and intellectual deficit, and a control participant: a preadolescent with ASD but no intellectual deficit (Asperger syndrome). The game is comprised of four phases: greetings, pairing, imitation, and closing. Field educators were involved, playing specific roles: visual or physical inciter. The use of a robot allows for catching the participants’ attention, playing the imitation game for a longer period of time than with a human partner, and preventing the game partner’s negative facial expressions resulting from tiredness, impatience, or boredom. The participants’ behavior was observed in terms of initial approach towards the robot, positioning relative to the robot in terms of distance and orientation, reactions to the robot’s voice or moves, signs of happiness, and imitation attempts. Results suggest a more and more natural approach towards the robot during the sessions, as well as a higher level of social interaction, based on the variations of the parameters listed above. We use these preliminary results to draw the next steps of our research work as well as identify further perspectives, with this aim in mind: improving social interactions with adolescents with ASD and intellectual deficit, allowing for better integration of these people into our societies. 展开更多
关键词 Human-Robot Interaction (HRI) Autism spectrum Disorder (ASD) IMITATION Artificial Intelligence Gesture Recognition Social Interaction
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Autologous cord blood vs individualized supplements in autistic spectrum disorder:CORDUS study results
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作者 Felician A Stancioiu Raluca Bogdan +1 位作者 Bogdan Ivanescu Radu Dumitrescu 《World Journal of Clinical Pediatrics》 2025年第1期101-112,共12页
BACKGROUND Cellular therapies have started an important new therapeutic direction in autistic spectrum disorder(ASD),and the ample diversity of ASD pathophysiology and the different types of cell therapies prompt an e... BACKGROUND Cellular therapies have started an important new therapeutic direction in autistic spectrum disorder(ASD),and the ample diversity of ASD pathophysiology and the different types of cell therapies prompt an equally ample effort to employ clinical studies for studying the ASD causes and cell therapies.Stem cells have yielded so far mixed results in clinical trials,and at patient level the results varied from impressive to no improvement.In this context we have administered autologous cord blood(ACB)and a non-placebo,material intervention repre-sented by an individualized combination of supplements(ICS)to ASD children.METHODS CORDUS clinical study is a crossover study in which both oral ICS and intravenous ACB were sequentially administered to 56 children;ACB was infused as an inpatient procedure.Treatment efficacy was evaluated pre-treatment and post-treatment at 6 months by an independent psychotherapist with Autism Treatment Evaluation Checklist,Quantitative Checklist for Autism in Toddlers and a 16-item comparative table score,after interviewing the children’s parents and therapists.Before and after each intervention participants had a set of blood tests including inflammatory,metabolic and oxidative markers,and the neuronal specific enolase.RESULTS No serious adverse reactions were noted during and after cord blood or supplement administration.ACB improved evaluation scores in 78%of children with age 3–7-years(n=28),but was much less effective in kids older than 8 years or with body weight of more than 35 kg(n=28;only 11%of children improved scores).ICS yielded better results than ACB in 5 cases out of 28,while in 23 kids ACB brought more improvement than ICS(P<0.05);high initial levels of inflammation and ferritin were associated with no improvement.Ample individual differences were noted in children's progress,and statistically significant improvements were seen after ACB on areas such as verbalization and social interaction,but not on irritability or aggressive behavior.CONCLUSION ACB has superior efficacy to ICS in ASD;high inflammation,ferritin,age and body weight predict less improvement;more clinical studies are needed for studying ACB efficacy in ASD. 展开更多
关键词 Autistic spectrum disorder Cord blood Stem cells NEUROINFLAMMATION Autologous stem cell treatment Neuronal specific enolase
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Dietary Soy Preserves Cognitive Function in Experimental Fetal Alcohol Spectrum Disorder: Role of Increased Signaling through Notch and Gonadotropin Releasing Hormone Networks
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作者 Suzanne M. de la Monte Ming Tong +3 位作者 Jason Ziplow Princess Mark Stephanie Van Van Ahn Nguyen 《Journal of Behavioral and Brain Science》 2025年第2期11-46,共36页
Background: Neurodevelopmental abnormalities in experimental fetal alcohol spectrum disorder (FASD) are associated with impaired signaling through complex pathways that mediate neuronal survival, growth, migration, en... Background: Neurodevelopmental abnormalities in experimental fetal alcohol spectrum disorder (FASD) are associated with impaired signaling through complex pathways that mediate neuronal survival, growth, migration, energy metabolism, and plasticity. Gestational dietary soy prevents alcohol-related impairments in placentation and FASD-associated fetal anomalies. Objective: This study was designed to determine if gestational dietary soy would be sufficient to normalize cognitive function in young adolescent offspring after chronic in utero exposure to alcohol. In addition, efforts were made to characterize the mechanisms of FASD prevention by maternal dietary soy. Methods: Pregnant Long Evans rats were fed isocaloric liquid diets containing 0% or 26% caloric ethanol with casein or soy isolate as the protein source from gestation day 6 through delivery/postnatal day 0 (P0). From P24 - P28, the offspring were subjected to Morris water maze (MWM) testing, and on P35, they were sacrificed to harvest temporal lobes for histopathologic and molecular studies. Results: The in-utero ethanol-exposed offspring exhibited significant performance impairments on the MWM test, and they had a significantly reduced mean brain weight with neuronal loss in the CA1 hippocampal region and evidence of white matter myelin loss. Gestational dietary soy nearly normalized MWM performance and preserved brain weight, hippocampal CA1 architecture, and white matter myelin staining in alcohol-exposed offspring. Mechanistically, the main positive effects of soy included increased temporal lobe expression of HES-1 and HIF-1α, reflecting enhanced Notch signaling, and broadly increased expression of GnRH network molecules, including Erb1, Gper1, GnRH, GnRH-R, KiSS, and KiSS-R, irrespective of gestational ethanol exposure. Conclusions: Dietary soy intervention early in pregnancy may reduce FASD-associated cognitive deficits. The findings suggest that targeting Notch and GnRH-related networks may help reduce long-term disability with FASD. Additional mechanistic and experimental research is needed to determine if longer-duration, postnatal dietary soy could prevent the adverse neurobehavioral effects of FASD. 展开更多
关键词 Fetal Alcohol spectrum Disorder Temporal Lobe Dietary Soy Insulin Signaling NOTCH Behavior Rat Model WNT Gene Expression GNRH Prenatal Alcohol Exposure
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Autism spectrum disorder:difficulties in diagnosis and microRNA biomarkers
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作者 Bridget Martinez Philip V.Peplow 《Neural Regeneration Research》 SCIE CAS 2025年第10期2776-2786,共11页
We performed a PubMed search for microRNAs in autism spectrum disorder that could serve as diagnostic biomarkers in patients and selected 17 articles published from January 2008 to December 2023,of which 4 studies wer... We performed a PubMed search for microRNAs in autism spectrum disorder that could serve as diagnostic biomarkers in patients and selected 17 articles published from January 2008 to December 2023,of which 4 studies were performed with whole blood,4 with blood plasma,5 with blood serum,1 with serum neural cell adhesion molecule L1-captured extracellular vesicles,1 with blood cells,and 2 with peripheral blood mononuclear cells.Most of the studies involved children and the study cohorts were largely males.Many of the studies had performed microRNA sequencing or quantitative polymerase chain reaction assays to measure microRNA expression.Only five studies had used real-time polymerase chain reaction assay to validate microRNA expression in autism spectrum disorder subjects compared to controls.The microRNAs that were validated in these studies may be considered as potential candidate biomarkers for autism spectrum disorder and include miR-500a-5p,-197-5p,-424-5p,-664a-3p,-365a-3p,-619-5p,-664a-3p,-3135a,-328-3p,and-500a-5p in blood plasma and miR-151a-3p,-181b-5p,-320a,-328,-433,-489,-572,-663a,-101-3p,-106b-5p,-19b-3p,-195-5p,and-130a-3p in blood serum of children,and miR-15b-5p and-6126 in whole blood of adults.Several important limitations were identified in the studies reviewed,and need to be taken into account in future studies.Further studies are warranted with children and adults having different levels of autism spectrum disorder severity and consideration should be given to using animal models of autism spectrum disorder to investigate the effects of suppressing or overexpressing specific microRNAs as a novel therapy. 展开更多
关键词 autism spectrum disorder BIOMARKER blood cells blood plasma blood serum DIAGNOSIS MICRORNA peripheral blood mononuclear cells serum neural cell adhesion molecule L1-captured extracellular vesicles whole blood
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Prompt fission neutron uranium logging(Ⅱ):dead-time effect of the neutron time spectrum
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作者 Yan Zhang Chi Liu +6 位作者 Shi-Liang Liu Hao-Ran Zhang Hai-Tao Wang Jin-Hui Qu Wen-Xing Hu Ren-Bo Wang Bin Tang 《Nuclear Science and Techniques》 2025年第2期82-94,共13页
The acquisition of neutron time spectrum data plays a pivotal role in the precise quantification of uranium via prompt fission neutron uranium logging(PFNUL).However,the impact of the detector dead-time effect remains... The acquisition of neutron time spectrum data plays a pivotal role in the precise quantification of uranium via prompt fission neutron uranium logging(PFNUL).However,the impact of the detector dead-time effect remains paramount in the accurate acquisition of the neutron time spectrum.Therefore,it is imperative for neutron logging instruments to establish a dead-time correction method that is not only uncomplicated but also practical and caters to various logging sites.This study has formulated an innovative equation for determining dead time and introduced a dead-time correction method for the neutron time spectrum,called the“dual flux method.”Using this approach,a logging instrument captures two neutron time spectra under disparate neutron fluxes.By carefully selecting specific“windows”on the neutron time spectrum,the dead time can be accurately ascertained.To substantiate its efficacy and discern the influencing factors,experiments were conducted utilizing a deuterium-tritium(D-T)neutron source,a Helium-3(3He)detector,and polyethylene shielding to collate and analyze the neutron time spectrum under varying neutron fluxes(at high voltages).The findings underscore that the“height”and“spacing”of the two windows are the most pivotal influencing factors.Notably,the“height”(fd)should surpass 2,and the“spacing”twd should exceed 200μs.The dead time of the 3 He detector determined in the experiment was 7.35μs.After the dead-time correction,the deviation of the decay coefficients from the theoretical values for the neutron time spectrum under varying neutron fluxes decreased from 12.4%to within 5%.Similarly,for the PFNUL instrument,the deviation in the decay coefficients decreased from 22.94 to 0.49%after correcting for the dead-time effect.These results demonstrate the exceptional efficacy of the proposed method in ensuring precise uranium quantification.The dual flux method was experimentally validated as a universal approach applicable to pulsed neutron logging instruments and holds immense significance for uranium exploration. 展开更多
关键词 PFNUL Neutron time spectrum Dead time Pulsed source Correction method
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Exploring impedance spectrum for lithium-ion batteries diagnosis and prognosis:A comprehensive review 被引量:2
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作者 Xinghao Du Jinhao Meng +2 位作者 Yassine Amirat Fei Gao Mohamed Benbouzid 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期464-483,I0010,共21页
Lithium-ion batteries have extensive usage in various energy storage needs,owing to their notable benefits of high energy density and long lifespan.The monitoring of battery states and failure identification are indis... Lithium-ion batteries have extensive usage in various energy storage needs,owing to their notable benefits of high energy density and long lifespan.The monitoring of battery states and failure identification are indispensable for guaranteeing the secure and optimal functionality of the batteries.The impedance spectrum has garnered growing interest due to its ability to provide a valuable understanding of material characteristics and electrochemical processes.To inspire further progress in the investigation and application of the battery impedance spectrum,this paper provides a comprehensive review of the determination and utilization of the impedance spectrum.The sources of impedance inaccuracies are systematically analyzed in terms of frequency response characteristics.The applicability of utilizing diverse impedance features for the diagnosis and prognosis of batteries is further elaborated.Finally,challenges and prospects for future research are discussed. 展开更多
关键词 Lithium-ion battery Impedance spectrum Temperature monitoring Failure diagnosis Health prognosis
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Uphill or downhill?Cropland use change and its drivers from the perspective of slope spectrum 被引量:2
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作者 PAN Sipei LIANG Jiale +1 位作者 CHEN Wanxu PENG Yelin 《Journal of Mountain Science》 SCIE CSCD 2024年第2期484-499,共16页
The continuous decrease of low-slope cropland resources caused by construction land crowding poses huge threat to regional sustainable development and food security.Slope spectrum analysis of topographic and geomorphi... The continuous decrease of low-slope cropland resources caused by construction land crowding poses huge threat to regional sustainable development and food security.Slope spectrum analysis of topographic and geomorphic features is considered as a digital terrain analysis method which reflects the macro-topographic features by using micro-topographic factors.However,pieces of studies have extended the concept of slope spectrum in the field of geoscience to construction land to explore its expansion law,while research on the slope trend of cropland from that perspective remains rare.To address the gap,in virtue of spatial analysis and geographically weighted regression(GWR)model,the cropland use change in the Yangtze River Basin(YRB)from 2000 to 2020 was analyzed and the driving factors were explored from the perspective of slope spectrum.Results showed that the slope spectrum curves of cropland area-frequency in the YRB showed a first upward then a downward trend.The change curve of the slope spectrum of cropland in each province(municipality)exhibited various distribution patterns.Quantitative analysis of morphological parameters of cropland slope spectrum revealed that the further down the YRB,the stronger the flattening characteristics,the more obvious the concentration.The province experienced the greatest downhill cropland climbing(CLC)was Shannxi,while province experienced the highest uphill CLC was Zhejiang.The most common cropland use change type in the YRB was horizontal expansion type.The factors affecting average cropland climbing index(ACCI)were quite stable in different periods,while population density(POP)changed from negative to positive during the study period.This research is of practical significance for the rational utilization of cropland at the watershed scale. 展开更多
关键词 Cropland climbing Land use change Slope spectrum Driving factors Geographically weighted regression Yangtze River Basin
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^(13)C NMR、FT-IR、Raman和建模技术对烟煤和无烟煤分子结构的应用研究 被引量:1
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作者 李元吉 代诚欣 +2 位作者 孟上九 张保勇 张强 《太原理工大学学报》 CAS 北大核心 2024年第6期1063-1072,共10页
【目的】探究高精度煤的结构演化及其机理的定量表征。【方法】通过显微组分鉴定、镜质体反射率、工业品质、元素分析和光谱分析,确定了烟煤(FS1)和无烟煤(ZY1)碳骨架结构、官能团的赋存状态等信息,并通过计算机辅助分子设计建立2个分... 【目的】探究高精度煤的结构演化及其机理的定量表征。【方法】通过显微组分鉴定、镜质体反射率、工业品质、元素分析和光谱分析,确定了烟煤(FS1)和无烟煤(ZY1)碳骨架结构、官能团的赋存状态等信息,并通过计算机辅助分子设计建立2个分子结构模型。【结果】结果表明,随着煤化作用的进行,烟煤到无烟煤过程中,亚甲基的损失速率比甲基的损失速率快,芳香性增强,芳香环的脂肪族链变短且支化度较高,含氧官能团逐渐减少,煤结晶程度增强,煤的化学结构趋于成熟稳定,且煤中的脂肪碳减少,芳香碳增加,甲基碳和亚甲基碳含量减少。经过多次尝试确定了芳香炭、脂肪族侧链和氧官能团之间的键合模式,获得最终的分子结构模型:C_(175)H_(162)O_(13)N_(2)(FS1)、C_(190)H_(159)O_(5)N_(3)(ZY1).该模型较好地反映煤的真实结构,模拟的^(13)C NMR光谱与实验光谱具有良好的一致性。上述研究为不同变质程度煤的分子结构演化提供了理论参考,为建立高可信度的分子结构表征提供了方法。 展开更多
关键词 ^(13)C NMR ft-ir RAMAN 分子结构模型
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Dynamic Update Scheme of Spectrum Information Based on Spectrum Opportunity Incentive in the Database-Assisted Dynamic Spectrum Management
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作者 Zhang Yu Chen Yong +1 位作者 He Panfeng Cai Yueming 《China Communications》 SCIE CSCD 2024年第3期75-90,共16页
To solve the problem of delayed update of spectrum information(SI) in the database assisted dynamic spectrum management(DB-DSM), this paper studies a novel dynamic update scheme of SI in DB-DSM. Firstly, a dynamic upd... To solve the problem of delayed update of spectrum information(SI) in the database assisted dynamic spectrum management(DB-DSM), this paper studies a novel dynamic update scheme of SI in DB-DSM. Firstly, a dynamic update mechanism of SI based on spectrum opportunity incentive is established, in which spectrum users are encouraged to actively assist the database to update SI in real time. Secondly, the information update contribution(IUC) of spectrum opportunity is defined to describe the cost of accessing spectrum opportunity for heterogeneous spectrum users, and the profit of SI update obtained by the database from spectrum allocation. The process that the database determines the IUC of spectrum opportunity and spectrum user selects spectrum opportunity is mapped to a Hotelling model. Thirdly, the process of determining the IUC of spectrum opportunities is further modelled as a Stackelberg game by establishing multiple virtual spectrum resource providers(VSRPs) in the database. It is proved that there is a Nash Equilibrium in the game of determining the IUC of spectrum opportunities by VSRPs. Finally, an algorithm of determining the IUC based on a genetic algorithm is designed to achieve the optimal IUC. The-oretical analysis and simulation results show that the proposed method can quickly find the optimal solution of the IUC, and ensure that the spectrum resource provider can obtain the optimal profit of SI update. 展开更多
关键词 database-assisted dynamic spectrum management HOTELLING information updating contribution spectrum information updating STACKELBERG
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Correction:Brillouin scattering spectrum for liquid detection and applications in oceanography
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作者 Yuanqing Wang Jinghao Zhang +6 位作者 Yongchao Zheng Yangrui Xu Jiaqi Xu Jiao Jiao Yun Su Hai-Feng Lü Kun Liang 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第1期47-47,共1页
After publication of this article1,it was brought to our at-tention that the mathematical expressions‘‰’were mis-takenly replaced by‘%’for salinities.Details are listed below.1.In the last sentence in abstract,“... After publication of this article1,it was brought to our at-tention that the mathematical expressions‘‰’were mis-takenly replaced by‘%’for salinities.Details are listed below.1.In the last sentence in abstract,“approximately 0.1℃and 0.5%”should be“approximately 0.1℃and 0.5‰”. 展开更多
关键词 SCATTERING LISTED spectrum
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Construction of a Cu@hollow TS-1 nanoreactor based on a hierarchical full-spectrum solar light utilization strategy for photothermal synergistic artificial photosynthesis
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作者 Sixian Zhu Qiao Zhao +5 位作者 Hongxia Guo Li Liu Xiao Wang Xiwei Qi Xianguang Meng Wenquan Cui 《Carbon Energy》 SCIE EI CAS CSCD 2024年第2期25-36,共12页
The artificial photosynthesis technology has been recognized as a promising solution for CO_(2) utilization.Photothermal catalysis has been proposed as a novel strategy to promote the efficiency of artificial photosyn... The artificial photosynthesis technology has been recognized as a promising solution for CO_(2) utilization.Photothermal catalysis has been proposed as a novel strategy to promote the efficiency of artificial photosynthesis by coupling both photochemistry and thermochemistry.However,strategies for maximizing the use of solar spectra with different frequencies in photothermal catalysis are urgently needed.Here,a hierarchical full-spectrum solar light utilization strategy is proposed.Based on this strategy,a Cu@hollow titanium silicalite-1 zeolite(TS-1)nanoreactor with spatially separated photo/thermal catalytic sites is designed to realize high-efficiency photothermal catalytic artificial photosynthesis.The space-time yield of alcohol products over the optimal catalyst reached 64.4μmol g−1 h−1,with the selectivity of CH3CH2OH of 69.5%.This rationally designed hierarchical utilization strategy for solar light can be summarized as follows:(1)high-energy ultraviolet light is utilized to drive the initial and difficult CO_(2) activation step on the TS-1 shell;(2)visible light can induce the localized surface plasmon resonance effect on plasmonic Cu to generate hot electrons for H2O dissociation and subsequent reaction steps;and(3)low-energy near-infrared light is converted into heat by the simulated greenhouse effect by cavities to accelerate the carrier dynamics.This work provides some scientific and experimental bases for research on novel,highly efficient photothermal catalysts for artificial photosynthesis. 展开更多
关键词 artificial photosynthesis full spectrum NANOREACTORS photothermal catalysis
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Floquet spectrum and universal dynamics of a periodically driven two-atom system
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作者 谢文柱 周正强 +2 位作者 李轩 崔思淼 孙明远 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期436-443,共8页
We investigate the Floquet spectrum and excitation properties of a two-ultracold-atom system with periodically driven interaction in a three-dimensional harmonic trap.The interaction between the atoms is changed by va... We investigate the Floquet spectrum and excitation properties of a two-ultracold-atom system with periodically driven interaction in a three-dimensional harmonic trap.The interaction between the atoms is changed by varying the s-wave scattering length in two ways,the cosine and the square-wave modulations.It is found that as the driving frequency increases,the Floquet spectrum exhibits two main features for both modulations,the accumulating and the spreading of the quasienergy levels,which further lead to different dynamical behaviors.The accumulation is associated with collective excitations and the persistent growth of the energy,while the spread indicates that the energy is bounded at all times.The initial scattering length,the driving frequency and amplitude can all significantly change the Floquet spectrum as well as the dynamics.However,the corresponding relation between them is valid universally.Finally,we propose a mechanism for selectively exciting the system to one specific state by using the avoided crossing of two quasienergy levels,which could guide preparation of a desired state in experiments. 展开更多
关键词 Floquet spectrum universal dynamics two-atom system avoided crossing
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Comparison of inebilizumab or rituximab in addition to glucocorticoid therapy for neuromyelitis optica spectrum disorders
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作者 Chu-Yuan Lou Yong Wang +4 位作者 Jia-Yuan Xing Teng Ma Lei Tao Xiao-Tang Wang Run-Sheng Wang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第6期1073-1078,共6页
AIM:To investigate the short-term efficacy and safety of inebilizumab for neuromyelitis optica spectrum disorders(NMOSD).METHODS:A total of 33 patients with NMOSD treated with inebilizumab(Group INB,n=15)or rituximab(... AIM:To investigate the short-term efficacy and safety of inebilizumab for neuromyelitis optica spectrum disorders(NMOSD).METHODS:A total of 33 patients with NMOSD treated with inebilizumab(Group INB,n=15)or rituximab(Group RTX,n=18)in addition to high-dose glucocorticoids were included.Both groups underwent hormone shock therapy during the acute phase.Subsequently,Group INB received inebilizumab injections during the remission phase,while Group RTX received rituximab injections.A comparison of aquaporins 4(AQP4)titer values,peripheral blood B lymphocyte counts,and visual function recovery was conducted before and 8wk after treatment.Additionally,adverse reactions and patient tolerability were analyzed after using inebilizumab treatment regimes.RESULTS:Following inebilizumab treatment,there was a significantly improvement in the visual acuity of NMOSD patients(P<0.05),accompanied by a notable decrease in AQP4 titer values and B lymphocyte ratio(P<0.05).Moreover,inebilizumab treatment showed a partial effect in preventing optic nerve atrophy(P<0.05).However,there were no significant differences in other therapeutic effects compared to rituximab,which has previously demonstrated substantial therapeutic efficacy(P>0.05).Furthermore,inebilizumab exhibited higher safety levels than that of rituximab injections.CONCLUSION:The combination of inebilizumab and high-dose glucocorticoids proves to be effective.In comparison to rituximab injections,inebilizumab displays better tolerance and safety.Moreover,it demonstrates a partial effect in preventing optic nerve atrophy.Thus,it stands as an effective method to reduce the disability rates and improve the daily living ability of patients with NMOSD. 展开更多
关键词 neuromyelitis optica spectrum disorders inebilizumab RITUXIMAB GLUCOCORTICOIDS
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Blockchain-Based MCS Detection Framework of Abnormal Spectrum Usage for Satellite Spectrum Sharing Scenario
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作者 Ning Yang Heng Wang +3 位作者 Jingming Hu Bangning Zhang Daoxing Guo Yuan Liu 《China Communications》 SCIE CSCD 2024年第2期32-48,共17页
In this paper, the problem of abnormal spectrum usage between satellite spectrum sharing systems is investigated to support multi-satellite spectrum coexistence. Given the cost of monitoring, the mobility of low-orbit... In this paper, the problem of abnormal spectrum usage between satellite spectrum sharing systems is investigated to support multi-satellite spectrum coexistence. Given the cost of monitoring, the mobility of low-orbit satellites, and the directional nature of their signals, traditional monitoring methods are no longer suitable, especially in the case of multiple power level. Mobile crowdsensing(MCS), as a new technology, can make full use of idle resources to complete a variety of perceptual tasks. However, traditional MCS heavily relies on a centralized server and is vulnerable to single point of failure attacks. Therefore, we replace the original centralized server with a blockchain-based distributed service provider to enable its security. Therefore, in this work, we propose a blockchain-based MCS framework, in which we explain in detail how this framework can achieve abnormal frequency behavior monitoring in an inter-satellite spectrum sharing system. Then, under certain false alarm probability, we propose an abnormal spectrum detection algorithm based on mixed hypothesis test to maximize detection probability in single power level and multiple power level scenarios, respectively. Finally, a Bad out of Good(BooG) detector is proposed to ease the computational pressure on the blockchain nodes. Simulation results show the effectiveness of the proposed framework. 展开更多
关键词 blockchain hypothesis test mobile crowdsensing satellite communication spectrum sharing
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Dietary L-proline supplementation ameliorates autism-like behaviors and modulates gut microbiota in the valproic acid-induced mouse model of autism spectrum disorder
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作者 Jingjing Fang Ruixuan Geng +2 位作者 Seong-Gook Kang Kunlun Huang Tao Tong 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2889-2905,共17页
The effective intervention strategy for autism spectrum disorder(ASD)are currently limited.Herein,we attempted to evaluate the potential of L-proline(Pro),a multifunctional amino acid,in ameliorating autismlike behavi... The effective intervention strategy for autism spectrum disorder(ASD)are currently limited.Herein,we attempted to evaluate the potential of L-proline(Pro),a multifunctional amino acid,in ameliorating autismlike behaviors and clarify the molecular mechanisms involved by using the typical valproic acid(VPA)-induced mouse model of ASD.Pro significantly attenuates repetitive behaviors and social dysfunction in ASD mice.The correlation analysis revealed that the beneficial effects of Pro on autism-like behaviors are related to the modulation of gut microbiota structure and composition.The histological analysis revealed that Pro could reverse the decrease of Nissl-positive cells in the prefrontal cortex(PFC)induced by VPA exposure.RNA sequencing demonstrated that Pro can also alter the PFC transcriptomic profile distinguished by the regulation of genes involved in Parkinson disease,neuroactive ligand-receptor interaction,oxidative phosphorylation,and mitogen activated protein kinase signaling pathway.Overall,dietary Pro supplementation may be a promising intervention strategy for ASD. 展开更多
关键词 L-PROLINE Autism spectrum disorder Gut microbiota Prefrontal cortex Behavior
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