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Multifaceted superoxide dismutase 1 expression in amyotrophic lateral sclerosis patients:a rare occurrence?
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作者 Ilaria Martinelli Jessica Mandrioli +5 位作者 Andrea Ghezzi Elisabetta Zucchi Giulia Gianferrari Cecilia Simonini Francesco Cavallieri Franco Valzania 《Neural Regeneration Research》 SCIE CAS 2025年第1期130-138,共9页
Amyotrophic lateral sclerosis(ALS)is a neuromuscular condition resulting from the progressive degeneration of motor neurons in the cortex,brainstem,and spinal cord.While the typical clinical phenotype of ALS involves ... Amyotrophic lateral sclerosis(ALS)is a neuromuscular condition resulting from the progressive degeneration of motor neurons in the cortex,brainstem,and spinal cord.While the typical clinical phenotype of ALS involves both upper and lower motor neurons,human and animal studies over the years have highlighted the potential spread to other motor and non-motor regions,expanding the phenotype of ALS.Although superoxide dismutase 1(SOD1)mutations represent a minority of ALS cases,the SOD1 gene remains a milestone in ALS research as it represents the first genetic target for personalized therapies.Despite numerous single case reports or case series exhibiting extramotor symptoms in patients with ALS mutations in SOD1(SOD1-ALS),no studies have comprehensively explored the full spectrum of extramotor neurological manifestations in this subpopulation.In this narrative review,we analyze and discuss the available literature on extrapyramidal and non-motor features during SOD1-ALS.The multifaceted expression of SOD1 could deepen our understanding of the pathogenic mechanisms,pointing towards a multidisciplinary approach for affected patients in light of new therapeutic strategies for SOD1-ALS. 展开更多
关键词 amyotrophic lateral sclerosis(ALS) AUTONOMIC extramotor GENOTYPE-PHENOTYPE multisystem involvement Parkinson’s disease sensory SOD1 superoxide dismutase 1 URINARY vocal cord palsy
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A Survey on Security Control and Estimation for Cyber-Physical Systems Under Cyber-Attacks:Advances,Challenges and Future Directions
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作者 Haoyang YU Zidong WANG +1 位作者 Lei ZOU Yezheng WANG 《Artificial Intelligence Science and Engineering》 2025年第1期1-16,共16页
Cyber-physical systems(CPSs)are regarded as the backbone of the fourth industrial revolution,in which communication,physical processes,and computer technology are integrated.In modern industrial systems,CPSs are widel... Cyber-physical systems(CPSs)are regarded as the backbone of the fourth industrial revolution,in which communication,physical processes,and computer technology are integrated.In modern industrial systems,CPSs are widely utilized across various domains,such as smart grids,smart healthcare systems,smart vehicles,and smart manufacturing,among others.Due to their unique spatial distribution,CPSs are highly vulnerable to cyber-attacks,which may result in severe performance degradation and even system instability.Consequently,the security concerns of CPSs have attracted significant attention in recent years.In this paper,a comprehensive survey on the security issues of CPSs under cyber-attacks is provided.Firstly,mathematical descriptions of various types of cyberattacks are introduced in detail.Secondly,two types of secure estimation and control processing schemes,including robust methods and active methods,are reviewed.Thirdly,research findings related to secure control and estimation problems for different types of CPSs are summarized.Finally,the survey is concluded by outlining the challenges and suggesting potential research directions for the future. 展开更多
关键词 cyber-physical systems cyber-attacks robust methods active methods secure estimation secure control
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Detection of Perfect Stealthy Attacks on Cyber-Physical Systems Subject to Measurement Quantizations: A Watermark-Based Strategy
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作者 Yu-Ang Wang Zidong Wang +2 位作者 Lei Zou Bo Shen Hongli Dong 《IEEE/CAA Journal of Automatica Sinica》 2025年第1期114-125,共12页
In this paper, the attack detection problem is investigated for a class of closed-loop systems subjected to unknownbutbounded noises in the presence of stealthy attacks. The measurement outputs from the sensors are qu... In this paper, the attack detection problem is investigated for a class of closed-loop systems subjected to unknownbutbounded noises in the presence of stealthy attacks. The measurement outputs from the sensors are quantized before transmission.A specific type of perfect stealthy attack, which meets certain rather stringent conditions, is taken into account. Such attacks could be injected by adversaries into both the sensor-toestimator and controller-to-actuator channels, with the aim of disrupting the normal data flow. For the purpose of defending against these perfect stealthy attacks, a novel scheme based on watermarks is developed. This scheme includes the injection of watermarks(applied to data prior to quantization) and the recovery of data(implemented before the data reaches the estimator).The watermark-based scheme is designed to be both timevarying and hidden from adversaries through incorporating a time-varying and bounded watermark signal. Subsequently, a watermark-based attack detection strategy is proposed which thoroughly considers the characteristics of perfect stealthy attacks,thereby ensuring that an alarm is activated upon the occurrence of such attacks. An example is provided to demonstrate the efficacy of the proposed mechanism for detecting attacks. 展开更多
关键词 Attack detection cyber-physical systems(CPSs) perfect stealthy attacks watermark-based strategy
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Crack and failure behaviors of sandstone subjected to dynamic loads visualized by micro-computed tomography
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作者 Xingyu Zhang Pengfei Guo +5 位作者 Xiangbo Gao Chunjiang Zou Kaiyu Wang Jinzhu Hu Yan Sun Liang Lei 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1459-1473,共15页
Microscopic dynamic failure behaviors of rocks are significant to rock engineering,which is still insufficiently understood.This study combines split Hopkinson pressure bar(SHPB)and micro-CT(computed tomography)to exp... Microscopic dynamic failure behaviors of rocks are significant to rock engineering,which is still insufficiently understood.This study combines split Hopkinson pressure bar(SHPB)and micro-CT(computed tomography)to explore the microscopic failure characteristics of sandstone under impact loading.SHPB is responsible for the dynamic test,and micro-CT is responsible for pre-and post-test inspections.The results show that the pores and defect influence the dynamic strength but do not alter the overall trend of increased strength with a higher impact level.The dynamical crack development is then analyzed.Three types of cracks(i.e.I-,Y-,and H-type)are identified to describe the crack development.When rock is simply fractured,only I-type crack exists due to tensile failure,and it grows irregularly.As the strain rate increases,I-type crack is transformed into Y-and H-type crack due to shear failure.Crack coalesces at that moment,and the complexity increases along the impact direction.The coalescence occurs preferentially in the area with more pores,and around a third of pores are involved,where the maximum contribution area is in the middle of sample.Microcracks are formed inside the rock blocks,and rock grains and fragments fill in the cracks.The dynamic crack development is accompanied by microcracks,while rock grains and fragments result from the development of these microcracks.In addition,the influence of a semi-penetrating defect perpendicular to the impact direction is investigated.The defect can impede stress transfer and concentrate energy consumption.The findings are expected to enhance understanding of rock dynamics and support rock engineering development. 展开更多
关键词 Dynamic rock failure 3D observation Microscopic failure mechanism
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Killing two birds with one stone:Enhancing the photoelectrochemical water splitting activity and stability of BiVO_(4)by Fe ions association 被引量:1
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作者 Hailang Deng Abebe Reda Woldu +5 位作者 Abdul Qayum Zanling Huang Weiwei Zhu Xiang Peng Paul K.Chu Liangsheng Hu 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第12期154-159,共6页
Bi VO_(4)is a promising semiconducting photoanode for photoelectrochemical(PEC)water splitting due to its suitable bandgap.However,the dissolution of V^(5+)and sluggish reaction kinetics at the surface in the oxygen e... Bi VO_(4)is a promising semiconducting photoanode for photoelectrochemical(PEC)water splitting due to its suitable bandgap.However,the dissolution of V^(5+)and sluggish reaction kinetics at the surface in the oxygen evolution reaction(OER)limit its applications.Herein,we report a convenient strategy to change the microenvironment by adding Fe(Ⅲ)into the electrolyte.During the PEC process,Fe(Ⅲ)ions not only improve the current density,but also show excellent stability toward Bi VO_(4).Consequently,the current increases by more than 1.7 times compared to that without Fe(Ⅲ).Photoelectrochemical,morphological,and structural characterizations reveal that the FeOOH co-catalyst produced in situ on the Bi VO_(4)photoanode by cyclical formation of the intermediates at the electrode/electrolyte interface during OER accelerates the OER kinetics and prevents photo-corrosion by suppressing the dissolution of V^(5+).The results reveal a new strategy for the multifunctional modification of photoanodes for efficient solar conversion. 展开更多
关键词 Photoelectrochemical water splitting Bi VO_(4)photoanodes Fe(Ⅲ)ions Oxygen evolution reaction Dynamic changes
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“Branched”structural transformation of the L1_(2)-Al_(3)Zr phase manipulated by Cu substitution/segregation in the Al-Cu-Zr alloy system 被引量:2
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作者 Lipeng Ding Mingqi Zhao +6 位作者 Flemming J.H.Ehlers Zhihong Jia Zezhong Zhang Yaoyao Weng Dominique Schryvers Qing Liu Hosni Idrissi 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第18期186-206,共21页
The effect of Cu on the evolution of the Al_(3)Zr phase in an Al-Cu-Zr cast alloy during solution treatment at 500℃has been thoroughly studied by combining atomic resolution high-angle annular dark-field scanning tra... The effect of Cu on the evolution of the Al_(3)Zr phase in an Al-Cu-Zr cast alloy during solution treatment at 500℃has been thoroughly studied by combining atomic resolution high-angle annular dark-field scanning transmission electron microscopy,energy-dispersive X-ray spectroscopy and first-principles cal-culations.The heat treatment initially produces a pure L1_(2)-Al_(3)Zr microstructure,allowing for about 13%Cu to be incorporated in the dispersoid.Cu incorporation increases the energy barrier for anti-phase boundary(APB)activation,thus stabilizing the L1_(2)structure.Additional heating leads to a Cu-induced“branched”path for the L1_(2)structural transformation,with the latter process accelerated once the first APB has been created.Cu atoms may either(i)be repelled by the APBs,promoting the transformation to a Cu-poor D0_(23) phase,or(ii)they may segregate at one Al-Zr layer adjacent to the APB,promoting a transformation to a new thermodynamically favored phase,Al4 CuZr,formed when these segregation layers are periodically arranged.Theoretical studies suggest that the branching of the L1_(2)transformation path is linked to the speed at which an APB is created,with Cu attraction triggered by a comparatively slow process.This unexpected transformation behavior of the L1_(2)-Al_(3)Zr phase opens a new path to un-derstanding,and potentially regulating the Al_(3)Zr dispersoid evolution for high temperature applications. 展开更多
关键词 Aluminum alloys TRIALUMINIDES Anti-phase boundary High-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) First-principles calculations
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Practical recommendations on stretching exercise:A Delphi consensus statement of international research experts
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作者 Konstantin Warneke Ewan Thomas +17 位作者 Anthony J.Blazevich José Afonso David G.Behm Paulo H.Marchetti Gabriel S.Trajano Masatoshi Nakamura Francisco Ayala Stefano Longo Nicolas Babault Sandro R.Freitas Pablo B.Costa Andreas Konrad Antoine Nordez Arnold Nelson Astrid Zech Anthony D.Kay Olyvia Dontit Jan Wilke 《Journal of Sport and Health Science》 2025年第5期110-123,共14页
Background:Stretching has wide appeal,but there seems to exist some mismatch between its purported applications and what the evidence shows.There is compelling evidence for some stretching applications,but for others,... Background:Stretching has wide appeal,but there seems to exist some mismatch between its purported applications and what the evidence shows.There is compelling evidence for some stretching applications,but for others,the evidence seems heterogeneous or unsupportive.The discrepancies even affect some systematic reviews,possibly due to heterogeneous eligibility criteria and search strategies.This consensus paper seeks to unify the divergent findings on stretching and its implications for both athletic performance and clinical practices by delivering evidence-based recommendations.Methods:A panel of 20 experts with a blend of practical experience and scholarly knowledge was assembled.The panel meticulously reviewed existing systematic reviews,defined key terminologies(e.g.,consensus definitions for different stretching modes),and crafted guidelines using a Delphi consensus approach(minimum required agreement:80%).The analysis focused on 8 topics,including stretching's acute and chronic(long-term)effects on range of motion,strength performance,muscle hypertrophy,stiffness,injury prevention,muscle recovery,posture correction,and cardiovascular health.Results:There was consensus that chronic and acute stretching(a)improves range of motion(although alternatives exist)and(b)reduces muscle stiffness(which may not always be desirable);the panel also agreed that chronic stretching(c)may promote vascular health,but more research is warranted.In contrast,consensus was found that stretch training does not(a)contribute substantively to muscle growth,(b)serve as an allencompassing injury prevention strategy,(c)improve posture,or(d)acutely enhance post-exercise recovery.Conclusion:These recommendations provide guidance for athletes and practitioners,highlighting research gaps that should be addressed to more comprehensively understand the full scope of stretching effects. 展开更多
关键词 Range of motion Strength Movement preparation Recovery Evidence-based practice STRETCH
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Research on the longitudinal protection of a through-type cophase traction direct power supply system based on the empirical wavelet transform
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作者 Lu Li Zeduan Zhang +5 位作者 Wang Cai Qikang Zhuang Guihong Bi Jian Deng Shilong Chen Xiaorui Kan 《Global Energy Interconnection》 EI CSCD 2024年第2期206-216,共11页
This paper proposes a longitudinal protection scheme utilizing empirical wavelet transform(EWT)for a through-type cophase traction direct power supply system,where both sides of a traction network line exhibit a disti... This paper proposes a longitudinal protection scheme utilizing empirical wavelet transform(EWT)for a through-type cophase traction direct power supply system,where both sides of a traction network line exhibit a distinctive boundary structure.This approach capitalizes on the boundary’s capacity to attenuate the high-frequency component of fault signals,resulting in a variation in the high-frequency transient energy ratio when faults occur inside or outside the line.During internal line faults,the high-frequency transient energy at the checkpoints located at both ends surpasses that of its neighboring lines.Conversely,for faults external to the line,the energy is lower compared to adjacent lines.EWT is employed to decompose the collected fault current signals,allowing access to the high-frequency transient energy.The longitudinal protection for the traction network line is established based on disparities between both ends of the traction network line and the high-frequency transient energy on either side of the boundary.Moreover,simulation verification through experimental results demonstrates the effectiveness of the proposed protection scheme across various initial fault angles,distances to faults,and fault transition resistances. 展开更多
关键词 Through-type Cophase traction direct power supply system Traction network Empirical wavelet transform(EWT) Longitudinal protection
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The effect of LPSO phase on the high-temperature oxidation of a stainless Mg-Y-Al alloy
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作者 Zhipeng Wang Zhao Shen +7 位作者 Yang Liu Yahuan Zhao Qingchun Zhu Yiwen Chen Jingya Wang Yangxin Li Sergio Lozano-Perez Xiaoqin Zeng 《Journal of Magnesium and Alloys》 CSCD 2024年第10期4045-4052,共8页
In this study,we investigated the oxidation of the Mg-11Y-1Al alloy at 500℃in an Ar-20%O2environment.Multiscale analysis showed the network-like long-period stacking ordered(LPSO)phase transformed into needle-like LP... In this study,we investigated the oxidation of the Mg-11Y-1Al alloy at 500℃in an Ar-20%O2environment.Multiscale analysis showed the network-like long-period stacking ordered(LPSO)phase transformed into needle-like LPSO and polygonal Mg24Y5 phases,leading to the formation of a high-dense network of needle-like oxides at the oxidation front.These oxides grew laterally along the oxide/matrix interfaces,forming a thicker,continuous scale that effectively blocked elemental diffusion.Hence,the preferential oxidation along the needle-like LPSO is believed to accelerate the formation of a thicker and continuous oxide scale,further improving the oxidation resistance of the Mg-11Y-1Al alloy. 展开更多
关键词 Mg alloy LPSO phase OXIDATION TEM TKD.
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Magnesium ferrites and their composites based photocatalysts:Synthesis approaches,effect of doping,and operational parameters on photocatalytic performance for wastewater remediation
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作者 Rohit Jasrotia Kanika Raj +5 位作者 Suman M.Ramya Rajesh Kumar Deepak Pathania Yogesh Kumar Abhishek Kandwal 《Journal of Magnesium and Alloys》 CSCD 2024年第10期3996-4044,共49页
In recent years,increased discharge of toxic effluents into water bodies has severely harmed ecosystems and human well-being.Various techniques are employed to remove contaminants,among which photocatalysis have prove... In recent years,increased discharge of toxic effluents into water bodies has severely harmed ecosystems and human well-being.Various techniques are employed to remove contaminants,among which photocatalysis have proven to be the most environment friendly and effective technique.This review focuses on MgFe_(2)O_(4),an exceptional photocatalyst owing to their small band gap,spherical shape,magnetic respon-sivity,stability,reusability,cost-effectiveness and small crystallite size.We have covered comprehensive comparison of research studies from the past decade to assess.Magnesium ferrite’s photocatalytic potential in pure,doped,and composite forms.Along with synthesis methods,degradation mechanisms,and shortcomings explained in detail.Furthermore,we have highlighted the enhanced photocatalytic capability of doped MgFe_(2)O_(4)and their nanocomposites towards the various organic contaminants upon visible light irradiation under a comparatively short period of time.Factors like cation distribution,dosage,pH,as well as methods for recovery and reuse are discussed to aid in production of more efficient photocatalysts.There has been a lack of information on the techniques that can be used to overcome the various shortcomings of MgFe_(2)O_(4)ferrite.Hence,we have accentuated on bringing forth such advanced techniques that would aid in driving the researchers’attention towards the practical and industrial application of the hybrid MgFe_(2)O_(4)nanoparticles.Lastly,the research gaps and industrial need of MgFe_(2)O_(4)ferrite-based materials were addressed to offer a concise view. 展开更多
关键词 MgFe_(2)O_(4)ferrite COMPOSITES PHOTODEGRADATION Wastewater remediation Pollutants.
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Preclinical Evaluation of the Antidiabetic Effect and Phytochemical HPLC-MS ESI-QTOF Analysis of Sclerocarya birrea (A. Rich) Hoscht Bark of Trunk Aqueous Extract in Alloxan-Induced Diabetic Wistar Rat
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作者 Ida Valerie Yasmina Ga San Nintie Traoré Lazare Belemnaba +8 位作者 Windingoudi Rimwagna Christian Ouedraogo Boukaré Kaboré Rémy Kindanloun Bationo Bonéwendé Mohamed Belemlilga Souleymane Compaoré Wendinmi Bertrand Florent Goumbri Salfo Ouedraogo Moumouni Koala Mathieu Nitiéma 《Pharmacology & Pharmacy》 2024年第11期364-387,共24页
Introduction: Diabetes is a serious public health problem requiring complex treatment. Numerous ethnopharmacological studies have reported the traditional use of Sclerocarya birrea in managing diabetic patients. This ... Introduction: Diabetes is a serious public health problem requiring complex treatment. Numerous ethnopharmacological studies have reported the traditional use of Sclerocarya birrea in managing diabetic patients. This study aims to demonstrate, preclinically, the antidiabetic effects of the aqueous decoction of S. birrea trunk bark. Methods: Phytochemical analysis was performed by HPLC-MS. The effects of the extracts (Sb5 and Sb25) and 0.9% NaCl on the normal blood glucose levels of the animals were determined. Diabetes induction was performed intraperitoneally by administering a single dose of alloxan (150 mg/kg) in normoglycemic rats. The antidiabetic effects of the extracts (Allox + Sb5, Allox + Sb25) and glibenclamide (Allox + Glib5) were determined in Alloxan-induced diabetic animals for four weeks. Results: Interpretation of mass spectra obtained by HPLC-MS allowed the tentative identification of vanillic acid-4-sulfate and rhamnetin in Sb extract. Investigated doses of Sb extract showed an antidiabetic impact similar to the reference, glibenclamide, with a return to normal blood glucose in all treated rats only after 4 days of treatment. Furthermore, Sb extract treatments reduced weight loss in diabetic rats. Sb had no negative impact on the balance of total cholesterol, triglycerides, high-density lipoprotein (HDL), and low-density lipoprotein (LDL). Conclusion: The present study demonstrated the antidiabetic efficacy and, to some extent, the beneficial effects of Sb extract on Alloxan-induced diabetic rats’ health. Detection of antidiabetic phytochemicals such as vanillic acid-4-sulfate and rhamnetin would justify this pharmacological property of the aqueous decoction of S. birrea trunk bark. 展开更多
关键词 Preclinical Study Sclerocarya birrea Antidiabetic Effect ALLOXAN HPLC-MS
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The Proteomic Research of the Cure of Experimental Diabetes Deafness by Granules of Eliminating Phlegm and Removing Blood Stasis 被引量:3
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作者 郭宏 熊大经 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2011年第2期88-97,共10页
Objective: Observing the expression changes of serum proteome in model rats after intervention of the Granules of Eliminating Phlegm and Removing Blood Stasis (豁痰祛瘀颗粒 also known as GEPRB), screening out and iden... Objective: Observing the expression changes of serum proteome in model rats after intervention of the Granules of Eliminating Phlegm and Removing Blood Stasis (豁痰祛瘀颗粒 also known as GEPRB), screening out and identifying the differentially expressed proteins by mass spectrometry and bioinformatics analysis, discussing the molecular mechanism of control the Diabetes deafness by GEPRB. Methods: By use of proteomics technology, the serum protein serum proteome of the control group, model control group, Duxil and each observation group were observed for 2-DE gel pattern matching, and the difference in the relative content of 2 times was chosen for the differentially expressed proteins. Identification of differentially expressed proteins by MALDI-TOF MS/MS, the authors further analysis the phosphorylation, subcellular localization, interaction, direct regulation, and transmembrane of the differences proteins by the way of bioinformatics analysis. Sixty SPF level SD rats elected in diabetic rats model group (abbreviated as DM group) were be randomly divided into 5 groups based on random number sheet, namely model control group, positive drug control group (Du-ke-xi group) and Mai-tong-fang high, medium and low dose group respectively. In addition, set of normal control group. 10 rats in each group. Results: By Coomassie brilliant blue staining, identified 51 differential protein spots dug from 2-D gel by mass spectrometry, successfully identified 13 non-redundant proteins. Most of the identified proteins were secreted protein and belong to different protein families. There were about 12 proteins have the transmembrane region from the authors’ result, ten of them were plasma membrane proteins. Conclusion: It’s suggesting that 13 differential proteins is most likely the protein response to GEPRB in vivo, these proteins may play key role for the treatment of GEPRB to Diabetes deafness. The two highly differentially expressed proteins Apolipoprotein E (apoE) and C3 may be a potential drug target of GEPRB. 展开更多
关键词 Granules of Eliminating Phlegm and Removing Blood Stasis also known as GEPRB Diabetes deafness also known as DD two-dimentional electrophoresis also known as 2-DE Matrix-assisted laser desorption ionization-time of flight- mass Spectrometry also known as MS Serum proteomics
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Electroencephalogram evidence for the activation of human mirror neuron system during the observation of intransitive shadow and line drawing actions 被引量:1
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作者 Huaping Zhu Yaoru Sun Fang Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第3期251-257,共7页
Previous studies have demonstrated that hand shadows may activate the motor cortex associated with the mirror neuron system in human brain. However, there is no evidence of activity of the human mirror neuron system d... Previous studies have demonstrated that hand shadows may activate the motor cortex associated with the mirror neuron system in human brain. However, there is no evidence of activity of the human mirror neuron system during the observation of intransitive movements by shadows and line drawings of hands. This study examined the suppression of electroencephalography mu waves (8-13 Hz) induced by observation of stimuli in 18 healthy students. Three stimuli were used: real hand actions, hand shadow actions and actions made by line drawings of hands. The results showed significant desynchronization of the mu rhythm ("mu suppression") across the sensodmotor cortex (recorded at C3, Cz and C4), the frontal cortex (recorded at F3, Fz and F4) and the central and right posterior parietal cortex (recorded at Pz and P4) under all three conditions. Our experimental findings suggest that the observation of "impoverished hand actions", such as intransitive movements of shadows and line drawings of hands, is able to activate widespread cortical areas related to the putative human mirror neuron system. 展开更多
关键词 neural regeneration clinical practice mirror neuron system action understanding direct matchinghypothesis mu suppression event-related desynchronization mu rhythm ELECTROENCEPHALOGRAM impoverished hand actions grants-supported paper photographs-containing paper neuroregeneration
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Spin Dynamics and Phonons in Chromites CoCr_(2)O_(4)and MnCr_(2)O_(4)
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作者 Wei Xu Gaoting Lin +11 位作者 Mingfang Shu Jinlong Jiao Jinfeng Zhu Qingyong Ren Manh Duc Le Xuan Luo Yuping Sun Yi Liu Zhe Qu Haidong Zhou Shang Gao Jie Ma 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第11期190-201,共12页
Spinel compounds are of great interest in both fundamental and application-oriented perspectives due to the geometric magnetic frustration inherent to their lattice and the resulting complex magnetic states.Here,we ap... Spinel compounds are of great interest in both fundamental and application-oriented perspectives due to the geometric magnetic frustration inherent to their lattice and the resulting complex magnetic states.Here,we applied x-ray diffraction,magnetization,heat capacity and powder inelastic neutron scattering measurements,along with theoretical calculations,to study the exotic properties of chromite-spinel oxides CoCr_(2)O_(4) and MnCr_(2)O_(4).The temperature dependence of the phonon spectra provides an insight into the correlation between oxygen motion and the magnetic order,as well as the magnetoelectric effect in the ground state of MnCr_(2)O_(4).Moreover,spin-wave excitations in CoCr_(2)O_(4) and MnCr_(2)O_(4) are compared with Heisenberg model calculations.This approach enables the precise determination of exchange energies and offers a comprehensive understanding of the spin dynamics and relevant exchange interactions in complicated spiral spin ordering. 展开更多
关键词 exchange PRECISE EXCITATION
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Mn^(4+) activated phosphors in photoelectric and energy conversion devices
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作者 Yang Ding Chunhua Wang +8 位作者 Lang Pei Qinan Mao Sateesh Bandaru Runtian Zheng Soumyajit Maitra Meijiao Liu Li-Hua Chen Bao-Lian Su Jiasong Zhong 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第11期277-299,I0007,共24页
Owing to their high luminous efficiency and tunable emission in both red light and far-red light regions,Mn^(4+)ion-activated phosphors have appealed significant interest in photoelectric and energy conversion devices... Owing to their high luminous efficiency and tunable emission in both red light and far-red light regions,Mn^(4+)ion-activated phosphors have appealed significant interest in photoelectric and energy conversion devices such as white light emitting diode(W-LED),plant cultivation LED,and temperature thermometer.Up to now,Mn^(4+)has been widely introduced into the lattices of various inorganic hosts for brightly redemitting phosphors.However,how to correlate the structure-activity relationship between host framework,luminescence property,and photoelectric device is urgently demanded.In this review,we thoroughly summarize the recent advances of Mn^(4+)doped phosphors.Meanwhile,several strategies like co-doping and defect passivation for improving Mn^(4+)emission are also discussed.Most importantly,the relationship between the protocols for tailoring the structures of Mn^(4+)doped phosphors,increased luminescence performance,and the targeted devices with efficient photoelectric and energy conversion efficiency is deeply correlated.Finally,the challenges and perspectives of Mn^(4+)doped phosphors for practical applications are anticipated.We cordially anticipate that this review can deliver a deep comprehension of not only Mn^(4+)luminescence mechanism but also the crystal structure tailoring strategy of phosphors,so as to spur innovative thoughts in designing advanced phosphors and deepening the applications. 展开更多
关键词 Mn^(4+) activator PHOSPHOR Structure tailoring Photoelectric device Energy conversion
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Study of Competitive Chelating Reaction between Lanthanum and Tribromoarsenazo in the Medium of Weak Acid by Capillary Zone Electrophoresis
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作者 胡涌刚 周培疆 +1 位作者 邓延倬 程介克 《Journal of Donghua University(English Edition)》 EI CAS 2003年第2期83-88,共6页
Two kinds of metal chelates of rare earth elements reacted with tribrimoarsenazo formed under the condition of critic acid were observed by simultaneous technique of capillary electrophoresisphotothermal interference ... Two kinds of metal chelates of rare earth elements reacted with tribrimoarsenazo formed under the condition of critic acid were observed by simultaneous technique of capillary electrophoresisphotothermal interference spectrometry. The tendency of the conversion between these chelates as functions of the mole ratio of the reagent and the metal, pH value and the elapsing time was investigated. Kinetic equation of competitive chelating reaction between the TBA-La (Ⅲ) and La (Ⅲ) -critic acid were established. It was found that the competitive chelating reaction follows secondorder kinetics, for this second-order reaction, k=5.55 L·mol-1·S-1. 展开更多
关键词 capillary electrophoresis PHOTOTHERMAL tribrimoar- senazo competitive chelating reaction
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Hypergraph-based Object-oriented Model and Hypergraph Theory for GIS 被引量:2
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作者 ZHANGJin GONGJianya 《Geo-Spatial Information Science》 2002年第1期37-43,共7页
This paper discusses the features and relevant theories of GIS spatial data model based on hypergraph,etc.The integrated concept model based on hypergraph and object_oriented model (HOOM) is proposed by the authors.Th... This paper discusses the features and relevant theories of GIS spatial data model based on hypergraph,etc.The integrated concept model based on hypergraph and object_oriented model (HOOM) is proposed by the authors.The principal contribution of this paper is that we study the K_section and other theories of hypergraph.An application example using HOOM is given at the end of the paper. 展开更多
关键词 HYPERGRAPH object_oriented GIS spatial data model HBDS DEM
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Morphologically templated nucleation of primary Si on AlP in hypereutectic Al-Si alloys 被引量:4
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作者 Xiangzhen Zhu Shihao Wang +2 位作者 Xixi Dong Xiangfa Liu Shouxun Ji 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2022年第5期36-45,共10页
AlP has been widely used as an effective heterogenous nucleus for primary Si phase in hypereutectic AlSi alloys,but the morphological correlation between AlP and primary Si is still confusing.In the present work,the m... AlP has been widely used as an effective heterogenous nucleus for primary Si phase in hypereutectic AlSi alloys,but the morphological correlation between AlP and primary Si is still confusing.In the present work,the morphologies of AlP crystals were studied comprehensively by experimental observation and theorical prediction.It is found that AlP collected from an Al-0.03 P melt could be divided into two categories:spinel twin crystals and non-twin crystals.During the nucleation process,these two kinds of AlP crystals triggered morphologically templated nucleation of primary Si phase,resulting in the formation of hexagonal primary Si twin and octahedral non-twin crystals,respectively.As such,the percentage of primary Si twin crystals in the experimental Al-18 Si alloy was also increased obviously after the morphologically templated nucleation via Al P.The morphologically templated nucleation also eliminated the dendritic growth of primary Si phase and the formation of hopper structures inside primary Si,forcing primary Si to maintain to be faceted solid crystals through layer-by-layer growing mechanism.The insight into morphologically templated nucleation offers a new view in understanding the mechanism of heterogeneous nucleation of primary Si phase on AlP nuclei. 展开更多
关键词 Aluminium alloys SOLIDIFICATION NUCLEATION Primary Si Grain refinement Morphology
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Drought-Induced Changes in Xylem Sap pH, ABA and Stomatal Conductance 被引量:2
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作者 GUOXiu-lin LIUZi-hui +1 位作者 Razzaq LIGuang-min 《Agricultural Sciences in China》 CAS CSCD 2004年第7期496-501,共6页
Upstream signals potentially regulating evaporation and stomatal conductance wereinvestigated using 6-8-leaf-old maize (Zea may L.) seedlings which were grown in agreenhouse. Pressure chamber was used to measure leaf ... Upstream signals potentially regulating evaporation and stomatal conductance wereinvestigated using 6-8-leaf-old maize (Zea may L.) seedlings which were grown in agreenhouse. Pressure chamber was used to measure leaf water potential and to collectxylem sap. The pH of xylem sap in stems was higher than that in root, and the abscisicacid (ABA) concentration in stems was the highest in well-watered seedlings. The ABAconcentration and pH of xylem sap in roots, stems and leaves increased, and the ABAconcentration in leaves reached the maximum during drought stress. The treatment ofroots with exogenous ABA solution (100molL-1) increased xylem sap ABA concentration inall organs measured, and induced stomatal closure, but did not change ABA distributionamong organs of maize seedlings. The combined effects of external pH buffer on pH, ABAof xylem sap and stomatal behavior indicated that pH, as a root-source signal to leavesunder drought stress, regulated stomatal closure through accumulating ABA in leaves orguard cells. 展开更多
关键词 DROUGHT Abscisic acid PH Xylem sap SIGNAL Stomatal conductance
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Hotspots of seabirds and marine mammals between New Zealand and the Ross Gyre:importance of hydrographic features 被引量:2
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作者 Claude R.JOIRIS Grant R.W.HUMPHRIES 《Advances in Polar Science》 2018年第4期254-261,共8页
This article is part of our long-term study on the quantitative at-sea distribution of the marine "upper trophic levels"—seabirds and marine mammals—in polar ecosystems, aiming at quantifying the factors i... This article is part of our long-term study on the quantitative at-sea distribution of the marine "upper trophic levels"—seabirds and marine mammals—in polar ecosystems, aiming at quantifying the factors influencing their distribution as well as detecting possible spatial and temporal changes, with special attention to hydrography and to global climate changes. During an expedition of icebreaking RV Polarstern in February 2010, along the North–South transect between New Zealand and the Ross Gyre, off the Ross Sea, 3200 seabirds belonging to 22 identified pelagic species were recorded during 338 half-hour transect counts. Four major hotspots were identified. These were in Sub-tropical Water off New Zealand(up to 300 birds per count), and at the main Southern Ocean fronts: the Sub-Antarctic Front(up to 240 per count), the Antarctic Front(up to 150 per count) and the Polar Front(up to 200 per count), representing the vast majority of recorded seabirds. The most numerous species in the three frontal zones were: prions—mainly slender-billed Pachyptila belcheri—and Salvin’s albatross Thalassarche [cauta]salvini. The eight more abundant species represented 2650 birds, i.e. more than 80% of the total. A random forest clustering method identified four groups of seabird species occupying similar oceanographic niches. 展开更多
关键词 seabird at-sea distribution transect from New Zealand to Antarctica hydrographic features
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