检索结果-南通市图书馆

Lipid droplets in the nervous system:involvement in cell metabolic homeostasis

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第3期20卷 740-750页

作者： Yuchen Zhang Yiqing Chen cheng zhuang Jingxuan Qi Robert Chunhua Zhao Jiao Wang School of Life Sciences Shanghai UniversityShanghaiChina School of Medicine Shanghai UniversityShanghaiChina Institute of Basic Medical Sciences Chinese Academy of Medical Sciences School of Basic MedicinePeking Union Medical CollegeBeijingChina Center of Excellence in Tissue Engineering Chinese Academy of Medical SciencesBeijingChina Beijing Key Laboratory of New Drug Development and Clinical Trial of Stem Cell Therapy BeijingChina

Lipid droplets serve as primary storage organelles for neutral lipids in neurons,glial cells,and other cells in the nervous system.Lipid droplet formation begins with the synthesis of neutral lipids in the endoplasmic reticulum.Previously,lipid droplets were recognized for their role in maintaining lipid metabolism and energy homeostasis;however,recent research has shown that lipid droplets are highly adaptive organelles with diverse functions in the nervous system.In addition to their role in regulating cell metabolism,lipid droplets play a protective role in various cellular stress responses.Furthermore,lipid droplets exhibit specific functions in neurons and glial cells.Dysregulation of lipid droplet formation leads to cellular dysfunction,metabolic abnormalities,and nervous system diseases.This review aims to provide an overview of the role of lipid droplets in the nervous system,covering topics such as biogenesis,cellular specificity,and functions.Additionally,it will explore the association between lipid droplets and neurodegenerative disorders.Understanding the involvement of lipid droplets in cell metabolic homeostasis related to the nervous system is crucial to determine the underlying causes and in exploring potential therapeutic approaches for these diseases.

关键词： Alzheimer's disease lipid droplet biogenesis lipid droplets lipid metabolism nervous system neurodegenerative disorders oxidative stress Parkinson's disease

Preparation of Chemically Recyclable Poly(ether-alt-ester) by the Ring Opening Polymerization of Cyclic Monomers Synthesized by Coupling Glycolide and Epoxides

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第2期42卷 168-175,I0006页

作者： Feng Ren zhuang-zhuang Liang Ming-Xin Niu Chen-Yang Hu Xuan Pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China

Polyester and polyether are two key oxygenated polymers, and completely alternative sequence of poly(ester-alt-ether) could efficiently combine the advantages(including flexibility, degradability, etc.) of both segments. Currently, despite their copolymers could be synthesized from one-pot mixture of cyclic esters and epoxides, perfectly alternative microstructure is very challenging to realize and typically restricted to certain monomer pairs. Moving forward, synthesizing poly(ester-alt-ether) from commercially available and largescale monomers would be a significant advance. For example, successfully commercialized poly(glycolic acid)(PGA), which is not easily soluble in polymers due to its high crystallinity and is brittle and difficult to control the degradation cycle, would encounter a new paradigm if engineered into poly(ester-altether). In this work, starting from the design of monomer with hybrid structures, we successfully synthesized a series of 1,4-dioxan-2-one containing different substituents based on glycolide(GA) and epoxides using commercially available Salen-Cr(III) and PPNCl catalytic systems.The new monomers underwent ring-opening polymerization(ROP) to form a series of poly(ester-alt-ether) with perfectly alternating glycolic acid and propylene glycol repeat units under catalytic system of thiourea/base. The poly(ester-alt-ether) have significantly lower glass-transition temperature than PGA. Additionally, the poly(ester-alt-ether) can be chemically recovered to monomer using Sn(Oct)2 or 1,8-diazabicyclo[5.4.0]undecane-7-ene(DBU) as a catalyst in solution, thus establishing a closed-loop life cycle. From monomers derived from GA and epoxides, this work furnishes a novel strategy for the synthesis of poly(ester-alt-ether) with chemical recyclability.

关键词： Polyester Polyether Alternative copolymer Ring-opening polymerization

A whole-net cooperative positioning method based on CDGNSS and inter-vehicle ranging

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第2期37卷 401-416页

作者： Shan HU Hongbo ZHAO Chen zhuang School of Electronics and Information Engineering Beihang UniversityBeijing 100191China

Relative positioning is recognized as an important issue for vehicles in urban environments.Multi-vehicle Cooperative Positioning(CP)techniques which fuse the Global Navigation Satellite System(GNSS)and inter-vehicle ranging have attracted attention in improving the performance of baseline estimation between vehicles.However,current CP methods estimate the baselines separately and ignore the interactions among the positioning information of different baselines.These interactions are called’information coupling’.In this work,we propose a new multivehicle precise CP framework using the coupled information in the network based on the Carrier Differential GNSS(CDGNSS)and inter-vehicle ranging.We demonstrate the benefit of the coupled information by deriving the Cramer-Rao Lower Bound(CRLB)of the float estimation in CP.To fully use this coupled information,we propose a Whole-Net CP(WN-CP)method which consists of the Whole-Net Extended Kalman Filter(WN-EKF)as the float estimation filter,and the Partial Baseline Fixing(PBF)as the ambiguity resolution part.The WN-EKF fuses the measurements of all baselines simultaneously to improve the performance of float estimation,and the PBF strategy fixes the ambiguities of the one baseline to be estimated,instead of full ambiguity resolution,to reduce the computation load of ambiguity resolution.Field tests involving four vehicles were conducted in urban environments.The results show that the proposed WN-CP method can achieve better performance and meanwhile maintain a low computation load compared to the existing methods.

关键词： GNSS Cooperative positioning Baseline Ambiguity resolution Information coupling

Understanding and improving fairness in cognitive diagnosis

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2024年第5期67卷 99-114页

作者： Zheng ZHANG le WU Qi LIU Jiayu LIU Zhenya HUANG Yu YIN Yan zhuang Weibo GAO Enhong CHEN Anhui Province Key Laboratory of Big Data Analysis and Application School of Computer Science and Technology& School of Data Science University of Science and Technology of China State Key Laboratory of Cognitive Intelligence School of Computer Science and Information Engineering Hefei University of Technology

Intelligent education is a significant application of artificial intelligence. One of the key research topics in intelligence education is cognitive diagnosis, which aims to gauge the level of proficiency among students on specific knowledge concepts(e.g., Geometry). To the best of our knowledge, most of the existing cognitive models primarily focus on improving diagnostic accuracy while rarely considering fairness issues; for instance, the diagnosis of students may be affected by various sensitive attributes(e.g., region). In this paper,we aim to explore fairness in cognitive diagnosis and answer two questions:(1) Are the results of existing cognitive diagnosis models affected by sensitive attributes?(2) If yes, how can we mitigate the impact of sensitive attributes to ensure fair diagnosis results? To this end, we first empirically reveal that several wellknown cognitive diagnosis methods usually lead to unfair performances, and the trend of unfairness varies among different cognitive diagnosis models. Then, we make a theoretical analysis to explain the reasons behind this phenomenon. To resolve the unfairness problem in existing cognitive diagnosis models, we propose a general fairness-aware cognitive diagnosis framework, FairCD. Our fundamental principle involves eliminating the effect of sensitive attributes on student proficiency. To achieve this, we divide student proficiency in existing cognitive diagnosis models into two components: bias proficiency and fair proficiency.We design two orthogonal tasks for each of them to ensure that fairness in proficiency remains independent of sensitive attributes and take it as the final diagnosed result. Extensive experiments on the Program for International Student Assessment(PISA) dataset clearly show the effectiveness of our framework.

关键词： fairness intelligent education cognitive diagnosis psychometrics adversarial learning

Aerial target threat assessment based on gated recurrent unit and self-attention mechanism

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2024年第2期35卷 361-373页

作者： CHEN Chen QUAN Wei SHAO zhuang School of Automation Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing 100081China

Aerial threat assessment is a crucial link in modern air combat, whose result counts a great deal for commanders to make decisions. With the consideration that the existing threat assessment methods have difficulties in dealing with high dimensional time series target data, a threat assessment method based on self-attention mechanism and gated recurrent unit(SAGRU) is proposed. Firstly, a threat feature system including air combat situations and capability features is established. Moreover, a data augmentation process based on fractional Fourier transform(FRFT) is applied to extract more valuable information from time series situation features. Furthermore, aiming to capture key characteristics of battlefield evolution, a bidirectional GRU and SA mechanisms are designed for enhanced features.Subsequently, after the concatenation of the processed air combat situation and capability features, the target threat level will be predicted by fully connected neural layers and the softmax classifier. Finally, in order to validate this model, an air combat dataset generated by a combat simulation system is introduced for model training and testing. The comparison experiments show the proposed model has structural rationality and can perform threat assessment faster and more accurately than the other existing models based on deep learning.

关键词： target threat assessment gated recurrent unit(GRU) self-attention(SA) fractional Fourier transform(FRFT)

An oscillation-free Hermite WENO scheme for hyperbolic conservation laws

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2024年第2期67卷 431-454页

作者： zhuang Zhao Jianxian Qiu School of Mathematical Sciences and Institute of Natural Sciences Shanghai Jiao Tong UniversityShanghai 200240China School of Mathematical Sciences and Fujian Provincial Key Laboratory of Mathematical Modeling and High-Performance Scientific Computing Xiamen UniversityXiamen 361005China

In this paper, the sixth-order oscillation-free Hermite weighted essentially non-oscillatory (OFHWENO) scheme is proposed for hyperbolic conservation laws on structured meshes, where the zeroth- andfirst-order moments are the variables for the governing equations. The main difference from other HWENOschemes existing in the literature is that we add high-order numerical damping terms in the first-order momentequations to control spurious oscillations for the OF-HWENO scheme. The OF-HWENO scheme not only canachieve the designed optimal numerical order, but also can be easily implemented as we use only one set ofstencils in the reconstruction procedure and the same reconstructed polynomials are applied for the zeroth- andfirst-order moment equations. In order to obtain the adaptive order resolution when facing discontinuities, atransition polynomial is added in the reconstruction, where the associated linear weights can also be any positivenumbers as long as their summation equals one. In addition, the OF-HWENO scheme still keeps compactnessas only immediate neighbor values are needed in the space discretization. Some benchmark numerical tests areperformed to illustrate the high-order accuracy, high resolution and robustness of the proposed scheme.

关键词： Hermite WENO scheme hyperbolic conservation laws oscillation-free adaptive order discontinuous Galerkin method

Enhancement of low-temperature toughness of Fe-Mn-C-Al alloy by rare earth Ce-modified inclusions

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research(International) 2024年第1期31卷 157-173页

作者： Guang-kai Yang Chang-ling zhuang Yi-zhuang Li Chen Hu Shao-bo Li College of Materials and Metallurgy Guizhou UniversityGuiyang550025GuizhouChina Department of Mechanical Engineering University of Hong KongHong Kong999077China The State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819LiaoningChina State Key Laboratory of Public Big Data Guizhou UniversityGuiyang550025GuizhouChina

Fe-Mn-C-Al alloys have been recognized as promising materials for certain low-temperature applications due to their exceptional mechanical properties and cost-effectiveness.However,their limited low-temperature toughness restricts their large-scale applications in specific scenarios.The influence of trace amounts of rare earth cerium(Ce)on the low-temperature toughness of Fe-18Mn-0.6C-1.8Al alloys was investigated.The addition of Ce effectively alters the inclu-sions in the alloy,transforming large-sized irregular inclusions into fine ellipsoidal rare earth inclusions.This leads to a significant reduction in both the proportion and average size of the inclusions,resulting in their effective dispersion throughout the matrix and improved cryogenic performance.The presence of Ce-containing inclusions within the matrix reduces stress concentration,thereby inhibiting microcrack formation and improving impact absorption energy.Specifi-cally,the addition of rare earth Ce alters the fracture behavior of the material at room temperature and low temperature,changing from brittle cleavage fracture to a more ductile failure mode.The impact toughness of the Fe-Mn-C-Al alloy is significantly improved by the addition of 0.0048 wt.%Ce,particularly at-196℃where the impact toughness reaches 103.6 J/cm^(2),representing an impressive improvement of 87.3%.

关键词： Fe-Mn-C-Al alloy Rare earth Low-temperature toughness Inclusion Fracture

GmSTF accumulation mediated by DELLA protein GmRGAs contributes to coordinating light and gibberellin signaling to reduce plant height in soybean

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

The Crop Journal 2024年第2期12卷 432-442页

作者： zhuang Li Qichao Tu Xiangguang Lyu Qican cheng Ronghuan Ji Chao Qin Jun Liu Bin Liu Hongyu Li Tao Zhao State Key Laboratory of Crop Gene Resources and Breeding Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China

Plant height influences plant architecture,lodging resistance,and yield performance.It is modulated by gibberellic acid(GA)metabolism and signaling.DELLA proteins,acting as central repressors of GA signaling,integrate various environmental and hormonal signals to regulate plant growth and development in Arabidopsis.We examined the role of two DELLA proteins,GmRGAa and GmRGAb,in soybean plant height control.Knockout of these proteins led to longer internodes and increased plant height,primarily by increasing cell elongation.GmRGAs functioned under different light conditions,including red,blue,and far-red light,to repress plant height.Interaction studies revealed that GmRGAs interacted with the blue light receptor GmCRY1b.Consistent with this,GmCRY1b partially regulated plant height via GmRGAs.Additionally,DELLA proteins were found to stabilize the protein GmSTF1/2,a key positive regulator of photomorphogenesis.This stabilization led to increased transcription of GmGA2ox-7b and subsequent reduction in plant height.This study enhances our understanding of DELLA-mediated plant height control,offering Gmrgaab mutants for soybean structure and yield optimization.

关键词： DELLA protein GmRGAs GmSTFs Plant height Soybean

A Chinese Multi-Specialty Delphi Consensus to Optimize RAASi Usage and Hyperkalaemia Management in Patients with Chronic Kidney Disease and Heart Failure

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Sciences Journal 2024年第2期39卷 79-90页

作者： Ming-Hui Zhao Wei Chen Hong cheng Bi-cheng Liu Zhi-Guo Mao zhuang Tian Gang Xu Jing-Min Zhou Renal Division Peking University First HospitalBeijing 100034China Department of Nephrology The First Affiliated HospitalSun Yat-Sen UniversityGuangzhou 510080China Department of Nephrology Capital Medical UniversityBeijing 100029China Department of Nephrology Southeast University Zhongda HospitalNanjing 210009China Department of Nephrology Shanghai Changzheng HospitalShanghai 200003China Department of Cardiology Peking Union Medical College HospitalBeijing 100730China Renal Division Tongji Medical College of Huazhong University of Science and TechnologyWuhan 430030China Department of Cardiology Zhongshan HospitalFudan UniversityShanghai 200032China

Objective Variations are present in common clinical practices regarding best practice in managing hyperkalaemia(HK),there is therefore a need to establish a multi-specialty approach to optimal renin angiotension-aldosterone system inhibitors(RAASi)usage and HK management in patients with chronic kidney disease(CKD)&heart failure(HF).This study aimed to establish a multi-speciality approach to the optimal use of RAASi and the management of HK in patients with CKD and HF.Methods A steering expert group of cardiology and nephrology experts across China were convened to discuss challenges to HK management through a nominal group technique.The group then created a list of 41 statements for a consensus questionnaire,which was distributed for a further survey in extended panel group of cardiologists and nephrologists across China.Consensus was assessed using a modified Delphi technique,with agreement defined as"strong"(≥75%andlection,and analysis were aided by an independent facilitator.Results A total of 150 responses from 21 provinces across China were recruited in the survey.Respondents were comprised of an even split(n=75,50%)between cardiologists and nephrologists.All 41 statements achieved the 75%consensus agreement threshold,of which 27 statements attained very strong consensus(≥90%agreement)and 14 attained strong consensus(agreement between 75%and 90%).Conclusion Based on the agreement levels from respondents,the steering group agreed a set of recommendations intended to improve patient outcomes in the use of RAASi therapy and HK management in China.

关键词： Sardiorenal syndrome chronic kidney failure heart failure hyperkalemia multidisciplinary communication RAASi