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Exploring impedance spectrum for lithium-ion batteries diagnosis and prognosis:A comprehensive review 被引量:1
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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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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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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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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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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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Is a Mini-Screen for Fetal Alcohol Spectrum Disorder Feasible?
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作者 Tyler Mueller Devin Evavold +2 位作者 June-Yung Kim Marilyn G. Klug Larry Burd 《Open Journal of Pediatrics》 2024年第4期767-781,共15页
Background: Fetal Alcohol Spectrum Disorders (FASDs) are a global public health concern with lifelong consequences for affected individuals. Recent prevalence studies suggest FASD prevalence rates range from 1-5% amon... Background: Fetal Alcohol Spectrum Disorders (FASDs) are a global public health concern with lifelong consequences for affected individuals. Recent prevalence studies suggest FASD prevalence rates range from 1-5% among school age children. Most people with FASD are not correctly diagnosed and inadequate screening to identify patients with increased risk may contribute to under-diagnosis. This study developed a 10-item screening tool for FASD and examined its feasibility. Methods: The sample consisted of 355 children who had been evaluated at an FASD clinic. Data from the 33-item Alcohol Related Neurodevelopmental Disorder Behavioral Checklist was used to develop a brief FASD screen by comparing the changes in Cronbach’s alpha for different combinations of items. The validity of the brief scale was then further examined using receiving operating characteristic analyses. Results: The 10-item screen demonstrated acceptable sensitivity, specificity, and accuracy to identify children at high risk for FASD. The percentage correctly classified was 91.3 and the area under the receiving operating characteristic curve was 0.971. Conclusions: This feasibility study demonstrated that a screen for FASD consisting of 10 items with yes or no responses can be completed in 3 - 4 minutes. The tool is brief, with a low administration burden and has acceptable epidemiologic performance characteristics including accuracy. Future research should examine the performance of this tool when used in larger, community-based populations where screening for FASD would be appropriate. 展开更多
关键词 Fetal Alcohol spectrum Disorders (FASDs) CHILDREN SCREENING PREVALENCE
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Occurrence of K1 and K2 serotypes and genotypic characteristics of extended spectrumβ-lactamases-producing Klebsiella pneumoniae isolated from selected hospitals in Malaysia
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作者 Nurul Syazrah Anuar Hazmin Hazman +5 位作者 Sharven Raj Jeyakumar Mohd Nasir Mohd Desa Hasni Idayu Saidi Siti Norbaya Masri Nur Afiza Aziz Nurshahira Sulaiman 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第1期30-38,共9页
Objective:To determine the distribution,phenotypic and genetic background of extended spectrumβ-lactamases(ESBL)-producing Klebsiella(K.)pneumoniae clinical isolates associated with K1 and K2 serotypes in two selecte... Objective:To determine the distribution,phenotypic and genetic background of extended spectrumβ-lactamases(ESBL)-producing Klebsiella(K.)pneumoniae clinical isolates associated with K1 and K2 serotypes in two selected hospitals in Malaysia.Methods:A total of 192 K.pneumoniae isolates were collected and subjected to antibiotic susceptibility,hypermucoviscosity test and multiplex PCR to detect the presence of K1-and K2-serotype associated genes.Multilocus sequence typing(MLST)was performed on ESBL-producing K.pneumoniae isolates presented with K1 and K2 serotypes,followed by phylogenetic analysis.Results:A total of 87 out of 192(45.3%)of the K.pneumoniae isolates collected were ESBL producers.However,only 8.3%(16/192)and 10.9%(21/192)of the total isolates were detected to carry K1-and K2-serotype associated genes,respectively.Statistical analysis showed that K1 and K2 capsular serotypes were not significantly associated with ESBL phenotype(P=0.196).However,they were significantly associated with hypervirulent,as demonstrated by the positive string test(P<0.001).MLST analysis revealed that ST23 as the predominant sequence type(ST)in the K1 serotype,while the ST in the K2 serotype is more diverse.Conclusions:Although the occurrence of ESBL-producing isolates among the hypervirulent strains was low,their coexistence warrants the need for continuous surveillance.MLST showed that these isolates were genetically heterogeneous. 展开更多
关键词 Extended spectrumβ-lactamases Klebsiella pneumoniae Capsular serotypes GENOTYPIC
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Joint Optimization for on-Demand Deployment of UAVs and Spectrum Allocation in UAVs-Assisted Communication
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作者 Chen Yong Liao Naiwen +2 位作者 WangWei Zhang Xianyu Zhang Yu 《China Communications》 SCIE CSCD 2024年第7期278-290,共13页
To improve the efficiency and fairness of the spectrum allocation for ground communication assisted by unmanned aerial vehicles(UAVs),a joint optimization method for on-demand deployment and spectrum allocation of UAV... To improve the efficiency and fairness of the spectrum allocation for ground communication assisted by unmanned aerial vehicles(UAVs),a joint optimization method for on-demand deployment and spectrum allocation of UAVs is proposed,which is modeled as a mixed-integer non-convex optimization problem(MINCOP).An algorithm to estimate the minimum number of required UAVs is firstly proposed based on the pre-estimation and simulated annealing.The MINCOP is then decomposed into three sub-problems based on the block coordinate descent method,including the spectrum allocation of UAVs,the association between UAVs and ground users,and the deployment of UAVs.Specifically,the optimal spectrum allocation is derived based on the interference mitigation and channel reuse.The association between UAVs and ground users is optimized based on local iterated optimization.A particle-based optimization algorithm is proposed to resolve the subproblem of the UAVs deployment.Simulation results show that the proposed method could effectively improve the minimum transmission rate of UAVs as well as user fairness of spectrum allocation. 展开更多
关键词 block coordinate descent method on-demand deployment spectrum allocation UAVs-assisted Communication
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Wideband spectrum sensing using step-sampling based on the multipath nyquist folding receiver
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作者 Kai-lun Tian Kai-li Jiang +5 位作者 Sen Cao Jian Gao Ying Xiong Bin Tang Xu-ying Zhang Yan-fei Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期523-536,共14页
Wideband spectrum sensing with a high-speed analog-digital converter(ADC) presents a challenge for practical systems.The Nyquist folding receiver(NYFR) is a promising scheme for achieving cost-effective real-time spec... Wideband spectrum sensing with a high-speed analog-digital converter(ADC) presents a challenge for practical systems.The Nyquist folding receiver(NYFR) is a promising scheme for achieving cost-effective real-time spectrum sensing,which is subject to the complexity of processing the modulated outputs.In this case,a multipath NYFR architecture with a step-sampling rate for the different paths is proposed.The different numbers of digital channels for each path are designed based on the Chinese remainder theorem(CRT).Then,the detectable frequency range is divided into multiple frequency grids,and the Nyquist zone(NZ) of the input can be obtained by sensing these grids.Thus,high-precision parameter estimation is performed by utilizing the NYFR characteristics.Compared with the existing methods,the scheme proposed in this paper overcomes the challenge of NZ estimation,information damage,many computations,low accuracy,and high false alarm probability.Comparative simulation experiments verify the effectiveness of the proposed architecture in this paper. 展开更多
关键词 Wideband spectrum sensing Sub-Nyquist sampling Step-sampling Nyquist folding receiver(NYFR) Multisignal processing
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Robust Space-Time Adaptive Track-Before-Detect Algorithm Based on Persymmetry and Symmetric Spectrum
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作者 Xiaojing Su Da Xu +1 位作者 Dongsheng Zhu Zhixun Ma 《Journal of Beijing Institute of Technology》 EI CAS 2024年第1期65-74,共10页
Underwater monopulse space-time adaptive track-before-detect method,which combines space-time adaptive detector(STAD)and the track-before-detect algorithm based on dynamic programming(DP-TBD),denoted as STAD-DP-TBD,ca... Underwater monopulse space-time adaptive track-before-detect method,which combines space-time adaptive detector(STAD)and the track-before-detect algorithm based on dynamic programming(DP-TBD),denoted as STAD-DP-TBD,can effectively detect low-speed weak targets.However,due to the complexity and variability of the underwater environment,it is difficult to obtain sufficient secondary data,resulting in a serious decline in the detection and tracking performance,and leading to poor robustness of the algorithm.In this paper,based on the adaptive matched filter(AMF)test and the RAO test,underwater monopulse AMF-DP-TBD algorithm and RAO-DP-TBD algorithm which incorporate persymmetry and symmetric spectrum,denoted as PSAMF-DP-TBD and PS-RAO-DP-TBD,are proposed and compared with the AMF-DP-TBD algorithm and RAO-DP-TBD algorithm based on persymmetry array,denoted as P-AMF-DP-TBD and P-RAO-DP-TBD.The simulation results show that the four methods can work normally with sufficient secondary data and slightly insufficient secondary data,but when the secondary data is severely insufficient,the P-AMF-DP-TBD and P-RAO-DP-TBD algorithms has failed while the PSAMF-DP-TBD and PS-RAO-DP-TBD algorithms still have good detection and tracking capabilities. 展开更多
关键词 space-time adaptive detection track before detect ROBUSTNESS persymmetric property symmetric spectrum AMF test RAO test
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Modified Black Widow Optimization-Based Enhanced Threshold Energy Detection Technique for Spectrum Sensing in Cognitive Radio Networks
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作者 R.Saravanan R.Muthaiah A.Rajesh 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2339-2356,共18页
This study develops an Enhanced Threshold Based Energy Detection approach(ETBED)for spectrum sensing in a cognitive radio network.The threshold identification method is implemented in the received signal at the second... This study develops an Enhanced Threshold Based Energy Detection approach(ETBED)for spectrum sensing in a cognitive radio network.The threshold identification method is implemented in the received signal at the secondary user based on the square law.The proposed method is implemented with the signal transmission of multiple outputs-orthogonal frequency division multiplexing.Additionally,the proposed method is considered the dynamic detection threshold adjustments and energy identification spectrum sensing technique in cognitive radio systems.In the dynamic threshold,the signal ratio-based threshold is fixed.The threshold is computed by considering the Modified Black Widow Optimization Algorithm(MBWO).So,the proposed methodology is a combination of dynamic threshold detection and MBWO.The general threshold-based detection technique has different limitations such as the inability optimal signal threshold for determining the presence of the primary user signal.These limitations undermine the sensing accuracy of the energy identification technique.Hence,the ETBED technique is developed to enhance the energy efficiency of cognitive radio networks.The projected approach is executed and analyzed with performance and comparison analysis.The proposed method is contrasted with the conventional techniques of theWhale Optimization Algorithm(WOA)and GreyWolf Optimization(GWO).It indicated superior results,achieving a high average throughput of 2.2 Mbps and an energy efficiency of 3.8,outperforming conventional techniques. 展开更多
关键词 Cognitive radio network spectrum sensing noise uncertainty modified black widow optimization algorithm energy detection technique
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Clinical characteristics of patients with early-and late-onset optic neuromyelitis optica spectrum disease
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作者 LI Fei LIU Ting +5 位作者 Yang Yi-hao LIN Hui-xia TONG jing-yi LI Zong-jun LIANG Bin-ji LI Qi-fu 《Journal of Hainan Medical University》 CAS 2024年第2期14-19,共6页
Objective:To analyze the different clinical features of patients with early-onset(EO-NMOSDs)and late-onset neuromyelitis optica spectrum diseases(LO-NMOSDs).Methods:A total of 51patients with neuromyelitis optica spec... Objective:To analyze the different clinical features of patients with early-onset(EO-NMOSDs)and late-onset neuromyelitis optica spectrum diseases(LO-NMOSDs).Methods:A total of 51patients with neuromyelitis optica spectrum disease who were diagnosed in our hospital for the first time from January 2015 to December 2022 were included in the First Affiliated Hospital of Hainan Medical College and divided into 22 cases in the EO-NMOSDs group and 29 cases in the LO-NMOSDs group according to whether the age of onset was 50 years old.The basic data,Extended Disability Status Scale(EDSS)score,blood and cerebrospinal fluid test indicators of the two groups were statistically analyzed.Results:There were no significant differences in demographic characteristics,clinical features and serum AQP-4 antibody positivity rate between the two groups(all P>0.05),and there were significant differences in triglycerides(TG),low-density lipoprotein(LDL),apolipoprotein A(APOA),apolipoprotein B(APOB)and lipoprotein a(P=0.010,P=0.048,P=0.014,P=0.061,P=0.001,respectively),and cerebrospinal fluid LDH,There were significant differences between microprotein quantification and EDSS score(P=0.018,P=0.034,P=0.025,respectively),and the level of microprotein quantification in cerebrospinal fluid of LO-NMOSDs had a certain correlation with the degree of disability(r=0.52,P<0.03).Conclusion:LO-NMOSDs and EO-NMOSDs group patients have similar demographic characteristics,serum AQP-4 antibody positive rate and clinical features,but compared with EO-NMOSDs,patients in LO-NMOSDs group are prone to abnormal lipid metabolism,higher trace proteins in cerebrospinal fluid and more likely to be disabled,and among LO-NMOSDs,the higher the trace protein in the cerebrospinal fluid,the more severe the disability status of patients. 展开更多
关键词 Optic neuromyelitis optica spectrum DISORDERS Late onset Cerebrospinal fluid microprotein quantification EDSS score
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Des-Arg(9)bradykinin as a causal metabolite for autism spectrum disorder
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作者 Zhong-Yu Huang Zi-Pan Lyu +3 位作者 Hong-Gui Li Hua-Zhi You Xiang-Na Yang Cai-Hui Cha 《World Journal of Psychiatry》 SCIE 2024年第1期88-101,共14页
BACKGROUND Early diagnosis and therapeutic interventions can greatly enhance the developmental trajectory of children with autism spectrum disorder(ASD).However,the etiology of ASD is not completely understood.The pre... BACKGROUND Early diagnosis and therapeutic interventions can greatly enhance the developmental trajectory of children with autism spectrum disorder(ASD).However,the etiology of ASD is not completely understood.The presence of confounding factors from environment and genetics has increased the difficulty of the identification of diagnostic biomarkers for ASD.AIM To estimate and interpret the causal relationship between ASD and metabolite profile,taking into consideration both genetic and environmental influences.METHODS A two-sample Mendelian randomization(MR)analysis was conducted using summarized data from large-scale genome-wide association studies(GWAS)including a metabolite GWAS dataset covering 453 metabolites from 7824 European and an ASD GWAS dataset comprising 18381 ASD cases and 27969 healthy controls.Metabolites in plasma were set as exposures with ASD as the main outcome.The causal relationships were estimated using the inverse variant weight(IVW)algorithm.We also performed leave-one-out sensitivity tests to validate the robustness of the results.Based on the drafted metabolites,enrichment analysis was conducted to interpret the association via constructing a protein-protein interaction network with multi-scale evidence from databases including Infinome,SwissTargetPrediction,STRING,and Metascape.RESULTS Des-Arg(9)-bradykinin was identified as a causal metabolite that increases the risk of ASD(β=0.262,SE=0.064,P_(IVW)=4.64×10^(-5)).The association was robust,with no significant heterogeneity among instrument variables(P_(MR Egger)=0.663,P_(IVW)=0.906)and no evidence of pleiotropy(P=0.949).Neuroinflammation and the response to stimulus were suggested as potential biological processes mediating the association between Des-Arg(9)bradykinin and ASD.CONCLUSION Through the application of MR,this study provides practical insights into the potential causal association between plasma metabolites and ASD.These findings offer perspectives for the discovery of diagnostic or predictive biomarkers to support clinical practice in treating ASD. 展开更多
关键词 Des-Arg(9)bradykinin Autism spectrum disorder Mendelian randomization METABOLITE Enrichment analysis
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Energy spectrum computed tomography multi-parameter imaging in preoperative assessment of vascular and neuroinvasive status in gastric cancer
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作者 Jing Wang Jian-Cheng Liang +1 位作者 Fa-Te Lin Jun Ma 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第8期2511-2520,共10页
BACKGROUND Vascular and nerve infiltration are important indicators for the progression and prognosis of gastric cancer(GC),but traditional imaging methods have some limitations in preoperative evaluation.In recent ye... BACKGROUND Vascular and nerve infiltration are important indicators for the progression and prognosis of gastric cancer(GC),but traditional imaging methods have some limitations in preoperative evaluation.In recent years,energy spectrum computed tomography(CT)multiparameter imaging technology has been gradually applied in clinical practice because of its advantages in tissue contrast and lesion detail display.AIM To explore and analyze the value of multiparameter energy spectrum CT imaging in the preoperative assessment of vascular invasion(LVI)and nerve invasion(PNI)in GC patients.METHODS Data from 62 patients with GC confirmed by pathology and accompanied by energy spectrum CT scanning at our hospital between September 2022 and September 2023,including 46 males and 16 females aged 36-71(57.5±9.1)years,were retrospectively collected.The patients were divided into a positive group(42 patients)and a negative group(20 patients)according to the presence of LVI/PNI.The CT values(CT40 keV,CT70 keV),iodine concentration(IC),and normalized IC(NIC)of lesions in the upper energy spectrum CT images of the arterial phase,venous phase,and delayed phase 40 and 70 keV were measured,and the slopes of the energy spectrum curves[K(40-70)]from 40 to 70 keV were calculated.Arterial Core Tip:To investigate the application value of multiparameter energy spectrum computed tomography(CT)imaging in the preoperative assessment of vascular and nerve infiltration in patients with gastric cancer(GC).The imaging data of GC patients were retrospectively analyzed to evaluate the accuracy and sensitivity of CT for identifying and quantifying vascular and nerve infiltration and for comparison with postoperative pathological results.The purpose of this study was to verify the clinical feasibility and potential advantages of multiparameter energy spectrum CT imaging in guiding preoperative diagnosis and treatment decision-making and to provide a new imaging basis for improving the diagnostic accuracy and prognosis of GC patients. 展开更多
关键词 Tomography X-ray computer Energy spectrum computed tomography Gastric cancer Vascular invasion Nerve invasion Cross-sectional study
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Fluid identification and tight oil layer classification for the southwestern Mahu Sag,Junggar Basin using NMR logging-based spectrum decomposition
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作者 Wenbiao Huang Yibing Guo +4 位作者 Jun Qin Zhongchen Ba Zongbin Zhang Luning Bai Heng Li 《Energy Geoscience》 EI 2024年第2期62-69,共8页
The intricate distribution of oil and water in tight rocks makes pinpointing oil layers challenging.While conventional identification methods offer potential solutions,their limited accuracy precludes them from being ... The intricate distribution of oil and water in tight rocks makes pinpointing oil layers challenging.While conventional identification methods offer potential solutions,their limited accuracy precludes them from being effective in their applications to unconventional reservoirs.This study employed nuclear magnetic resonance(NMR)spectrum decomposition to dissect the NMR T_(2)spectrum into multiple subspectra.Furthermore,it employed laboratory NMR experiments to ascertain the fluid properties of these sub-spectra,aiming to enhance identification accuracy.The findings indicate that fluids of distinct properties overlap in the T_(2)spectra,with bound water,movable water,bound oil,and movable oil appearing sequentially from the low-value zone to the high-value zone.Consequently,an oil layer classification scheme was proposed,which considers the physical properties of reservoirs,oil-bearing capacity,and the characteristics of both mobility and the oil-water two-phase flow.When applied to tight oil layer identification,the scheme's outcomes align closely with actual test results.A horizontal well,deployed based on these findings,has produced high-yield industrial oil flow,underscoring the precision and dependability of this new approach. 展开更多
关键词 Nuclear magnetic resonance Fluid identification Oil layer identification NMR T_(2)spectrum decomposition Normal distribution simulation
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基于SPI-RRV指数中国气象干旱及其风险时空演变特征研究 被引量:3
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作者 杨肖丽 罗定 +4 位作者 叶周兵 谢灵枫 任立良 江善虎 袁山水 《水资源保护》 EI CSCD 北大核心 2024年第1期44-51,共8页
为全面揭示变化环境下我国多维气象干旱特征,耦合气象干旱指数(SPI)和可靠性-回弹性-脆弱性(RRV)指数,提出了一种基于SPI-RRV指数的干旱风险评价方法,定量评价了中国气象干旱及其风险的时空演变特征。结果表明:SPI-RRV指数具有特征稳定... 为全面揭示变化环境下我国多维气象干旱特征,耦合气象干旱指数(SPI)和可靠性-回弹性-脆弱性(RRV)指数,提出了一种基于SPI-RRV指数的干旱风险评价方法,定量评价了中国气象干旱及其风险的时空演变特征。结果表明:SPI-RRV指数具有特征稳定和时空可比性强的特点,能够较为准确地评估气象干旱风险时空演变特征;南方平均干旱栅格比、干旱月占比和频次大于北方,湿润区和半湿润区干旱历时短、烈度大,半干旱区和干旱区干旱历时长、烈度相对较小;干旱高风险区转移具有显著年代际变化规律,空间上从西北向西南地区转移。 展开更多
关键词 气象干旱 标准化降水指数 可靠性-回弹性-脆弱性指数 干旱风险
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水资源-能源-粮食-生态系统耦合协调及驱动力分析 被引量:2
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作者 杨明明 朱永楠 +2 位作者 赵勇 杨文静 樊煜 《人民黄河》 CAS 北大核心 2024年第3期58-63,共6页
为加深对我国水资源、能源、粮食、生态系统协同演变趋势的认识,构建水资源-能源-粮食-生态多维系统指标体系,运用耦合协调度模型对我国2005—2020年水资源-能源-粮食-生态系统耦合协调度进行评价,并采用多因素归因分析法进行驱动力分... 为加深对我国水资源、能源、粮食、生态系统协同演变趋势的认识,构建水资源-能源-粮食-生态多维系统指标体系,运用耦合协调度模型对我国2005—2020年水资源-能源-粮食-生态系统耦合协调度进行评价,并采用多因素归因分析法进行驱动力分析。结果表明:我国水资源-能源-粮食-生态系统耦合协调度从2005年的0.55增长到2020年的0.84,各地区耦合协调度从勉强协调发展水平过渡到中级协调发展水平,各子系统对耦合协调度上升的驱动分别经历了由粮食子系统到生态子系统再到水资源子系统主导的过程;能源子系统的贡献率虽然比较小,但是未来可能是各地区提升水资源-能源-粮食-生态系统多维系统协调发展水平的突破口。 展开更多
关键词 水资源-能源-粮食-生态 耦合协调度 多因素归因分析 驱动力
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深部煤储层孔裂隙结构对煤层气赋存的影响-以鄂尔多斯盆地东缘大宁-吉县区块为例 被引量:1
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作者 邓泽 王红岩 +3 位作者 姜振学 丁蓉 李永洲 王涛 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第8期106-123,共18页
深部煤储层孔隙–裂缝结构对深部煤层气资源潜力评价和勘探开发具有重要意义。选取鄂尔多斯盆地东缘大宁–吉县区块DJ57井本溪组5个煤岩样品为研究对象,在煤岩煤质参数测试的基础上,采用气体吸附法、高压压汞法和微米CT扫描等测试手段,... 深部煤储层孔隙–裂缝结构对深部煤层气资源潜力评价和勘探开发具有重要意义。选取鄂尔多斯盆地东缘大宁–吉县区块DJ57井本溪组5个煤岩样品为研究对象,在煤岩煤质参数测试的基础上,采用气体吸附法、高压压汞法和微米CT扫描等测试手段,对深部煤储层中的纳米级孔隙-微米级裂缝进行多尺度定量表征,综合评价不同尺度的孔裂隙结构特征。再结合渗透率和甲烷等温吸附试验,探讨了微观孔裂隙对深部煤储层中煤层气的赋存和渗流的影响。研究结果表明:基于多种孔隙表征方法对深部煤储层孔裂隙进行多尺度定量表征,其孔裂隙体积分布类型主要以“U”型为主,呈现出微孔与微裂缝并存双峰态,主要集中在0.3~1.5 nm和>100μm的范围内。其中,微孔(<2 nm)、介孔(2~50 nm)、宏孔(50 nm~10μm)和微裂缝(>10μm)体积平均分别占总孔裂隙体积的80.18%,6.70%,1.65%和11.47%。随着微孔发育而吸附气量呈增大的趋势,微孔可以提供大量吸附点位,为深部煤层气的吸附和赋存提供场所。随着微裂缝发育而游离气量呈增大的趋势,微裂缝可以提供大量储集空间,为深部煤层气的富集提供空间条件。此外,微裂缝在三维空间中相互连通,形成网状结构,连通性强。随着微裂缝越发育,煤储层渗透率越大,微裂缝增强了煤层气的渗流能力。纳米级孔隙和微米级裂隙发育特征分别控制着深部煤层气吸附能力和开发潜力。 展开更多
关键词 深部煤层气 孔隙-裂缝 全尺度表征 大宁-吉县区块
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