检索结果-南通市图书馆

Gut microbiota:closely tied to the regulation of circadian clock in the development of type 2 diabetes mellitus

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2020年第7期133卷 817-825页

作者： Lu ding xin-Hua Xiao Department of Endocrinology Key Laboratory of EndocrinologyMinistry of HealthPeking Union Medical College HospitalDiabetes Research Center of Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China

Type 2 diabetes mellitus(T2DM),a worldwide epidemic disease,has caused tremendous economic and social burden,but the pathogenesis remains uncertain.Nowadays,the impact of unrhythmic circadian clock caused by irregular sleep and unhealthy diet on T2DM has be increasingly studied.However,the contribution of the endogenous circadian clock system to the development of T2DM has not yet been satisfactorily explored.It is now becoming clear that the gut microbiota and the circadian clock interact with each other to regulate the host metabolism.Considering all these above,we reviewed the literature related to the gut microbiota,circadian clock,and T2DM to elucidate the idea that the gut microbiota is closely tied to the regulation of the circadian clock in the development of T2DM,which provides potential for gut microbiota-directed therapies to ameliorate the effects of circadian disruptions linked to the occurrence and development of T2DM.

关键词： Gut microbiota Circadian clock Type 2 diabetes mellitus Metabolites

Adjacent mode resonance of a hydraulic pipe system consisting of parallel pipes coupled at middle points

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2023年第3期44卷 363-380页

作者： xin FAN Changan ZHU Xiaoye MAO Hu ding Department of Precision Machinery and Precision Instruments University of Science and Technology of ChinaHefei 230022China State-owned Machinery Factory in Wuhu Wuhu 241007Anhui ProvinceChina Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechanoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200444China

The coupling vibration of a hydraulic pipe system consisting of two pipes is studied.The pipes are installed in parallel and fixed at their ends,and are restrained by clips to one bracket at their middle points.The pipe subjected to the basement excitation at the left end is named as the active pipe,while the pipe without excitation is called the passive pipe.The clips between the two pipes are the bridge for the vibration energy.The adjacent natural frequencies will enhance the vibration coupling.The governing equation of the coupled system is deduced by the generalized Hamilton principle,and is discretized to the modal space.The modal correction is used during the discretization.The investigation on the natural characters indicates that the adjacent natural frequencies can be adjusted by the stiffness of the two clips and bracket.The harmonic balance method(HBM)is used to study the responses in the adjacent natural frequency region.The results show that the vibration energy transmits from the active pipe to the passive pipe swimmingly via the clips together with a flexible bracket,while the locations of them are not node points.The adjacent natural frequencies may arouse wide resonance curves with two peaks for both pipes.The stiffness of the clip and bracket can release the vibration coupling.It is suggested that the stiffness of the clip on the passive pipe should be weak and the bracket should be strong enough.In this way,the vibration energy is reflected by the almost rigid bracket,and is hard to transfer to the passive pipe via a soft clip.The best choice is to set the clips at the pipe node points.The current work gives some suggestions for weakening the coupled vibration during the dynamic design of a coupled hydraulic pipe system.

关键词： hydraulic pipe system coupling vibration adjacent mode coupling parallel pipe conveying fluid harmonic balance method(HBM)

An all-silicon design of a high-efficiency broadband transmissive terahertz polarization convertor

在线全文

学校读者我要写书评

暂无评论

Frontiers of Optoelectronics 2023年第4期16卷 91-99页

作者： Xiaohua xing Die Zou xin ding Jianquan Yao Liang Wu College of Precision Instrument and Optoelectronics Engineering Key Laboratory of Optoelectronics Information and Technology(Ministry of Education)Tianjin UniversityTianjin 300072China

Polarization,a fundamental behavior of electromagnetic waves,holds immense potential across diverse domains such as environmental monitoring,biomedicine,and ocean exploration.However,achieving efcient modulation of terahertz waves with wide operational bandwidth poses signifcant challenges.Here,we introduce an all-silicon polarization converter designed specifcally to operate in the terahertz range of the electromagnetic spectrum.Simulation results demonstrate that the average conversion efciency of cross-linear waves exceeds 80%across a wide frequency range spanning from 1.00 to 2.32 THz,with the highest conversion efciency peaking at an impressive 99.97%.Additionally,our proposed structure facilitates linear-to-circular polarization conversion with an ellipticity of 1 at 0.85 THz.Furthermore,by rotating the crossshaped microstructure,active control over arbitrary polarization states can be achieved.To summarize,the proposed structure ofers remarkable fexibility and ease of integration,providing a reliable and practical solution for achieving broadband and efcient polarization conversion of terahertz waves.

关键词： Broadband High efficiency Polarization conversion All-silicon

Interception time and uncertainty optimization for tangent-impulse orbit interception problem

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2022年第3期18卷 418-440页

作者： Yang Hong Li xin-hong ding Wen-zhev Department of Aerospace Science and Technology Space Engineering UniversityNo.1 BaYi RoadHuaiRou DistrictBeijing101416China

The traditional tangent impulse interception problem does not consider the influence of actual deviation.However,by taking the actual state deviation of the interceptor into the orbit design process,an interception orbit that is more robust than the nominal orbit can be obtained.Therefore,we study the minimum time interception problem and the minimum terminal interception error problem under tangent impulse conditions and give an orbit optimization method that considers the interception time and the interception uncertainty.First,we express the interceptor's transfer time equation as a form of flight path angle,establish a global optimization model for solving the minimum time tangent impulse interception and give a hybrid optimization algorithm based on Augmented Lagrange Genetic Algorithm-Sequential Quadratic Programming(ALGA-SQP).Secondly,we use the universal time equation and Bootstrap resampling technology to calculate the interceptor's terminal error distribution and establish the relevant global optimization model by using the circumscribed cuboid volume of the interceptor's terminal position error ellipsoid as the optimization index.Finally,we combined the above two singleobjective optimization models to establish a global multi-objective optimization model that considers interception time and interception uncertainty and gave a hybrid multi-objective optimization algorithm based on Non-dominated Sorting Genetic Algorithm Ⅱ-Goal Achievement Method(NSGA2-GAM).The simulation example verifies the effectiveness of this method.

关键词： Tangent impulse interception Minimum time Interception uncertainty Multi-objective optimization Hybrid optimization

Heterostructuring an equiatomic CoNiFe medium-entropy alloy for enhanced yield strength and ductility synergy

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2022年第8期41卷 2894-2905页

作者： xin-xin Ding Jing Wang Dong Liu Chang Wang Ping Jiang Hua Qu Guang-Hua Liu Fu-Ping Yuan Xiao-Lei Wu School of Physical Science and Technology Tiangong UniversityTianjin300387China State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of ScienceBeijing100190China School of Engineering Science University of Chinese Academy of SciencesBeijing100049China Special Steel Department Central Iron and Steel Research InstituteBeijing100081China

High-/medium-entropy alloys(H/MEAs)of face-centered-cubic-structured single phase usually suffer from a glaring drawback of low yield strength.Even worse,the trade-off emerges frustratingly between strength and ductility as strength increases.Here,the lamellar heterostructure(HS)is designed in an equiatomic ternary CoNiFe ME A by means of cold rolling followed by an incomplete recrystallization annealing.The lamellar HS consists of the soft recrystallized grains as well as severely deformed structures which are partly reserved.By comparison to the coarse-grained counterpart,the lamellar HS,shows a well enhanced yield strength-ductility synergy,together with an increased yield strength.This is ascribed to the hetero-deformation-induced(HDI)stress in HS during tensile deformation.Accordingly,the HDI strain hardening is induced,serving as an important addition to the conventional forest hardening.The HDI hardening is evidenced experimentally to account for a large proportion of global strain hardening.Furthermore,a fully recrystallized microstructure is obtained to show a simultaneous increase in both yield strength and ductility.The microstructures are evaluated in detail prior to and after tensile deformation by using the electron backscattered diffraction and transmission electron microscope observations.The mechanism for HDI strain hardening in various microstructures is analyzed to correlate to the evolution of microstructures in terms of the kernel average misorientation values,Schmid factor,and dislocation behaviors in response to plastic deformation.

关键词： Heterostructure(HS) Medium-entropy alloy(MEA) Hetero-deformation Ductility Strength

A Fast Tongue Detection and Location Algorithm in Natural Environment

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2022年第12期73卷 4727-4742页

作者： Lei Zhu Guojiang xin xin Wang Changsong ding Hao Liang Qilei Chen School of Informatics Hunan University of Chinese MedicineChangsha410208China TCM Big Data Analysis Laboratory of Hunan Changsha410208China Department of Computer Science University of Massachusetts LowellLowell01854USA

The collection and extraction of tongue images has always been an important part of intelligent tongue diagnosis.At present,the collection of tongue images generally needs to be completed in a sealed,stable light environment,which is not conducive to the promotion of extensive tongue image and intelligent tongue diagnosis.In response to the problem,a newalgorithm named GCYTD(GELU-CA-YOLO Tongue Detection)is proposed to quickly detect and locate the tongue in a natural environment,which can greatly reduce the restriction of the tongue image collection environment.The algorithm is based on the YOLO(You Only Look Once)V4-tiny network model to detect the tongue.Firstly,the GELU(Gaussian Error Liner Units)activation function is integrated into the model to improve the training speed and reduce the number of model parameters;then,the CA(Coordinate Attention)mechanism is integrated into the model to enhance the detection precision and improve the failure tolerance of the model.Compared with the other classical algorithms,Experimental results show thatGCYTD algorithm has a better performance on the tongue images of all types in terms of training speed,tongue detection speed and detection precision,etc.The lighter model can contribute on deploying the tongue detection model on small mobile terminals.

关键词： Tongue detection YOLO V4-tiny CA mechanism GELU

A Furan-based Phosphaphenanthrene-containing Derivative as a Highly Efficient Flame-retardant Agent for Epoxy Thermosets without Deteriorating Thermomechanical Performances

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2022年第3期40卷 233-240,I0005页

作者： Hao-xin Niu Hong-Liang ding Jia-Li Huang xin Wang Lei Song Yuan Hu State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230026China

In order to reduce greenhouse gas emissions, developing flame retardants from bio-based resources has aroused extensive interest in recent years. In this work, we utilized furfural(biomass) and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide(DOPO) to synthesize a biobased co-curing agent(FGD) to combine with 4,4'-diaminodiphenyl methane(DDM) for obtaining a low-phosphorus loading flame-retardant epoxy thermosets. The introduction of FGD decreased the activation energy of the curing progress, enhanced the mechanical properties of the epoxy thermosets, and did not affect the glass transition temperature of the epoxy thermosets. EP-5.0 had a lower thermal degradation rate and a doubled char yield compared with EP-0. The phosphorus content of EP-5.0 was only 0.45 wt%, while EP-5.0 reached the UL-94 V-0 rating with a high LOI value of 32%. Compared with EP-0, the PHRR of EP-2.5 and EP-5.0 decreased by 22.3% and 31.3%, respectively. The SEM results showed that the addition of FGD made the char residues more uniform and denser, which could effectively prevent combustible volatiles from escaping from the degradation area to the flame area and isolate the heat transfer so that the epoxy thermosets had an excellent flame-retardant performance.

关键词： Furfural DOPO Bio-based co-curing agent Flame-retardant performance

A structural developmental neural network with information saturation for continual unsupervised learning

在线全文

学校读者我要写书评

暂无评论

CAAI Transactions on Intelligence Technology 2023年第3期8卷 780-795页

作者： Zhiyong ding Haibin Xie Peng Li xin Xu College of Intelligence Science and Technology National University of Defense TechnologyChangshaChina

In this paper,we propose a structural developmental neural network to address the plasticity‐stability dilemma,computational inefficiency,and lack of prior knowledge in continual unsupervised learning.This model uses competitive learning rules and dynamic neurons with information saturation to achieve parameter adjustment and adaptive structure development.Dynamic neurons adjust the information saturation after winning the competition and use this parameter to modulate the neuron parameter adjustment and the division timing.By dividing to generate new neurons,the network not only keeps sensitive to novel features but also can subdivide classes learnt repeatedly.The dynamic neurons with information saturation and division mechanism can simulate the long short‐term memory of the human brain,which enables the network to continually learn new samples while maintaining the previous learning results.The parent‐child relationship between neurons arising from neuronal division enables the network to simulate the human cognitive process that gradually refines the perception of objects.By setting the clustering layer parameter,users can choose the desired degree of class subdivision.Experimental results on artificial and real‐world datasets demonstrate that the proposed model is feasible for unsupervised learning tasks in instance increment and class incre-ment scenarios and outperforms prior structural developmental neural networks.

关键词： neural network pattern classification unsupervised learning

Roles of NG2 Glia in Cerebral Small Vessel Disease

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neuroscience Bulletin 2023年第3期39卷 519-530页

作者： Yixi He Zhenghao Li Xiaoyu Shi Jing ding xin Wang Department of Neurology Zhongshan HospitalFudan UniversityShanghai 200032China State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science Institutes of Brain ScienceFudan UniversityShanghai 200032China Institute of Neuroscience MOE Key Laboratory of Molecular NeurobiologyNMUShanghai 200433China

Cerebral small vessel disease(CSVD)is one of the most prevalent pathologic processes affecting 5%of people over 50 years of age and contributing to 45%of dementia cases.Increasing evidence has demonstrated the pathological roles of chronic hypoperfusion,impaired cerebral vascular reactivity,and leakage of the blood–brain barrier in CSVD.However,the pathogenesis of CSVD remains elusive thus far,and no radical treatment has been developed.NG2 glia,also known as oligodendrocyte precursor cells,are the fourth type of glial cell in addition to astrocytes,microglia,and oligodendrocytes in the mammalian central nervous system.Many novel functions for NG2 glia in physiological and pathological states have recently been revealed.In this review,we discuss the role of NG2 glia in CSVD and the underlying mechanisms.

关键词： NG2 glia Oligodendrocyte precursor cell Cerebral small vessel disease White matter injury