检索结果-南通市图书馆

超高效液相色谱-串联质谱法定量检测日本沼虾不同组织中氨基脲含量

在线全文

学校读者我要写书评

暂无评论

食品安全质量检测学报 2024年第2期15卷 83-92页

作者：徐磊孙博怿王俊吴琦芳高晟周冬仁农业农村部淡水渔业健康养殖重点实验室湖州313001 湖州市渔业环境与水产品质量安全重点实验室湖州313001 浙江省淡水水产研究所湖州313001

目的建立超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)测定日本沼虾(Macrobrachium nipponense)不同组织部位中不同形态氨基脲(semicarbazide,SEM)的检测方法。方法样品用66.7%甲醇溶液洗脱后,经盐酸酸化水解,2-硝基苯甲醛过夜衍生,调pH至7.3~7.4后,用乙酸乙酯提取,分析物采用UPLC-MS/MS定性检测,稳定同位素内标法进行定量测定。结果SEM在0.25~20.00μg/kg范围内线性关系良好,相关系数大于0.999,肌肉、头壳、背壳、头足胸、眼柄和鳃6个组织的方法检出限为0.25μg/kg(S/N≥3),定量限为0.50μg/kg(S/N≥10),肝胰腺的方法检出限为0.5μg/kg,定量限为1.0μg/kg,相对标准偏差不大于5.20%。虾壳中SEM含量最高,肌肉中含量最低,肌肉中SEM主要以游离态形式存在,虾壳中SEM主要以结合态形式存在。结论本方法灵敏度高、重现性好,可用于日本沼虾不同组织中不同形态SEM的定量测定。日本沼虾不同组织中SEM的存在形态与含量均存在巨大差异。

关键词：超高效液相色谱-串联质谱法日本沼虾氨基脲

Distance, Depth and Puncture Angle for Cisterna Magna in Chinese Adults as Read from Magnetic Resonance Imaging

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2015年第12期128卷 1683-1685页

作者： Zong-Xin Cao qi-wu fang Jian-Xiong An Cai-Cai Liu Xiao-Yan qian Rui-qi Li Doris K Cope John P Williams Department of Anesthesiology Weifang Medical University Weifang Shandong 261000 China Department of Anesthesiology Pain Medicine and Critical Care Medicine Aviation General Hospital of China Medical University and Beijing Institute of Translational Medicine Chinese Academy of Sciences Beijing 100012 China Department of Medical Imaging Aviation General Hospital of China Medical University and Beijing Institute of Translational Medicine Chinese Academy of Sciences Beijing 100012 China Department of Anesthesiology University of Pittsburgh Pittsburgh PA 15213 USA

INTRODUCTION The cisterna magna is a space lying between the cerebellum and medulla oblongata that is important in collecting cerebral spinal fluid （CSF） in some patients with contraindication or the impossibility o... 详细信息

关键词： Cisterna Magna Puncture Magnetic Resonance Imaging

Neuroprotective effects of chaperone-mediated autophagy in neurodegenerative diseases

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2024年第6期19卷 1291-1298页

作者： qi Jia Jin Li Xiaofeng Guo Yi Li You wu Yuliang Peng Zongping fang Xijing Zhang Department of Anesthesiology and Perioperative Medicine and Department of Intensive Care Unit Xijing Hospital The Fourth Military Medical University Department of Critical Care Medicine Translational Research Institute of Brain and Brain-Like Intelligence Shanghai Fourth People's Hospital School of Medicine Tongji University

Chaperone-mediated autophagy is one of three types of autophagy and is characterized by the selective degradation of proteins. Chaperone-mediated autophagy contributes to energy balance and helps maintain cellular homeostasis, while providing nutrients and support for cell survival. Chaperone-mediated autophagy activity can be detected in almost all cells, including neurons. Owing to the extreme sensitivity of neurons to their environmental changes, maintaining neuronal homeostasis is critical for neuronal growth and survival. Chaperone-mediated autophagy dysfunction is closely related to central nervous system diseases. It has been shown that neuronal damage and cell death are accompanied by chaperone-mediated autophagy dysfunction. Under certain conditions, regulation of chaperone-mediated autophagy activity attenuates neurotoxicity. In this paper, we review the changes in chaperone-mediated autophagy in neurodegenerative diseases, brain injury, glioma, and autoimmune diseases. We also summarize the most recent research progress on chaperone-mediated autophagy regulation and discuss the potential of chaperone-mediated autophagy as a therapeutic target for central nervous system diseases.

关键词： chaperone-mediated autophagy neurodegenerative disease neuronal homeostasis neuroprotection

Development of component stiffness equations for thread-fixed one-side bolt connections to an enclosed rectangular hollow section column under tension

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Structural and Civil Engineering 2024年第4期18卷 568-586页

作者： Fu-Wei wu Yuan-qi LI Department of Structural Engineering Tongji UniversityShanghai 200092China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China

The derivation and validation of analytical equations for predicting the tensile initial stiffness of threadfixed one-side bolts(TOBs),connected to enclosed rectangular hollow section(RHS)columns,is presented in this *** unknown stiffness components are considered:the TOBs connection and the enclosed RHS ***,the trapezoidal thread of TOB,as an equivalent cantilevered beam subjected to uniformly distributed loads,is analyzed to determine the associated *** on the findings,the thread-shank serial-parallel stiffness model of TOB connection is *** analysis of the tensile stiffness of the enclosed RHS face due to two bolt forces,the four sidewalls are treated as rotation constraints,thus reducing the problem to a two-dimensional plate *** to the load superposition method,the deflection of the face plate is resolved into three components under various boundary and load *** to the plate deflection theory of Timoshenko,the analytical solutions for the three deflections are derived in terms of the variables of bolt spacing,RHS thickness,height to width ratio,***,the validity of the above stiffness equations is verified by a series of finite element(FE)models of T-stub *** proposed component stiffness equations are an effective supplement to the component-based method.

关键词： initial stiffness component based method thread-fixed one-side bolt rectangular hollow sections analytical equation

Adaptive Algorithms on Maximizing Monotone Nonsubmodular Functions

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

Journal of the Operations Research Society of China 2024年第2期12卷 428-445页

作者： Bin Liu Hui Su Shu-fang Gong qi-Zhi fang School of Mathematical Sciences Ocean Universityof ChinaQingdao266100ShandongChina

Submodular optimization is widely used in large *** order to speed up the problems solving,it is essential to design low-adaptive algorithms to achieve acceleration in *** general,the function values are given by a value oracle,but in practice,the oracle queries may consume a lot of ***,how to strike a balance between optimizing them is *** this paper,we focus on maximizing a normalized and strictly monotone set function with the diminishing-return ratio under a cardinality constraint,and propose two algorithms to deal with *** apply the adaptive sequencing technique to devise the first algorithm,whose approximation ratio is arbitrarily close to 1-e^(-γ)in O(logn·log(log k/γ)) adaptive rounds,and requires O(logn^(2)·log(log k/γ)) *** by adding preprocessing and parameter estimation steps to the first algorithm,we get the second *** second algorithm trades a small sacrifice in adaptive complexity for a significant improvement in query *** the same approximation and adaptive complexity,the query complexity is improved *** the best of our knowledge,this is the first paper of designing adaptive algorithms for maximizing a monotone function using the diminishing-return ratio.

关键词： Approximation algorithm Adaptivity Nonsubmodular maximization Cardinality constraint

Adaptive sampling for corrugated plate digitization using a laser displacement sensor

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

Science China(Technological Sciences) 2024年第5期67卷 1510-1523页

作者： wu ChengXing qi qi CHEN BaiJin YANG JiXiang DING Han State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China

The surface quality of a corrugated plate directly determines the heat transfer property of the thermal power mechanical *** detection methods are impractical for real-world production,being slow and *** contrast,the point laser displacement sensor,employing the optical triangle method,emerges as a promising device for assessing parts with variable curvature and highly reflective *** its benefits,high-density sampling by an innate frequency introduces challenges such as data redundancy and a poor signal-to-noise ratio,potentially affecting the efficiency and precision of subsequent data *** address these challenges,adjustable frequency data sampling has been developed for this sensor,allowing adaptive sampling for corrugated plate *** process begins with surface digitization to extract discrete points,which are transformed into intersection curves using the B-spline fitting ***,dominant points are identified,considering multigeometric constraints for curvature and arch ***,the sampling signal is adjusted based on the distribution information of dominant *** results indicate that the proposed method effectively minimizes redundant sampling without compromising the accurate capture of essential geometric features.

关键词： corrugated plate laser displacement sensor adaptive sampling dominant point curvature arch height

Extending the detection limit:innovations in infrared quantum dot photodetectors reaching up to 18μm

在线全文

学校读者我要写书评

暂无评论

Light(Science & Applications) 2024年第8期13卷 1445-1447页

作者： Chong wu Wang qi Jie Wang Centre for OptoElectronics and Biophotonics School of Electrical and Electronic EngineeringNanyang Technological UniversitySingapore 639798Singapore Centre for Disruptive Photonic Technologies School of Physical and Mathematical SciencesNanyang Technological UniversitySingaporeSingapore

A regrowth method was used to synthesize large-sized colloidal quantum dots(CQDs).With the assistance of doping engineering,the synthesized CQD detectors demonstrate exceptional long-wavelength infrared detection performance,reaching up to 18μm,significantly extending the spectral response limit for CQD-based infrared *** detectors also achieve a reasonably high detectivity of 6.6×10^(8)Jones.

关键词： limit quantum sized

Total flavonoids of Astragalus membranaceus protect against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced neurotoxicity in mice by inhibiting ferroptosis through SLC7A11/GPX-4 signaling pathway

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

Food Science and Human Wellness 2024年第1期13卷 414-420页

作者： Zitian Gao Gaorui Wang Yujie Chen wuke Yuan Jun Cai Aiping Feng Jie fang qi Xu Xiaojun wu School of Public Health Shanghai University of Traditional Chinese MedicineShanghai 201203China Shanghai Key Laboratory of Compound Chinese Medicines The Ministry of Education(MOE)Key Laboratory for Standardization of Chinese MedicineInstitute of Chinese Materia MedicaShanghai University of Traditional Chinese MedicineShanghai 201203China Longhua Hospital affiliated to Shanghai University of Traditional Chinese Medicine Shanghai University of Traditional Chinese MedicineShanghai 201203China

Parkinson’s disease(PD)is a common neurodegenerative disorder with no *** membranaceus is used in Chinese culture as a food supplement to boost *** present study aimed to explore the neuroprotective effects of total flavonoids extracted from ***(TFA)and their protective *** offered neuroprotection against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)in the mouse model of Parkinsonism,by improving behavior performance in the gait analysis and pole test,and inhibiting the decline of tyrosine hydroxylase(TH)positive neurons and TH protein expression in substantia nigra of *** also prevented 1-methyl-4-phenylpyridinium(MPP+)induced neurotoxicity in SHSY5Y cells,by increasing GSH and GSH/GSSG ratio,and reducing reactive oxygen *** addition,the neuroprotective effects of TFA were associated with its ability to restore MPTP/MPP+induced downregulation of SLC7A11 and glutathione peroxidase 4(GPX-4).In conclusion,we demonstrated that TFA exerted significant neuroprotection against MPTP/MPP+induced neurodegeneration by inhibiting ferroptosis through the regulation of SLC7A11/GPX-4 axis,suggesting the use of TFA as a possible food supplement in the prevention of PD.

关键词： Parkinson’s disease Total fl avonoids of Astragalus membranaceus Ferroptosis SLC7A11

Design and Implementation of Nonlinear Precoding for MIMO-SDMA Toward 6G Wireless

在线全文

学校读者我要写书评

暂无评论

China Communications 2024年第1期21卷 69-87页

作者： Chaowu wu Yue Xiao Shu fang Gang wu National Key Laboratory of Wireless Communications University of Electronic Science and Technology of ChinaChengdu 611731China

In this paper,we present a novel and robust nonlinear precoding(NLP)design and detection structure specifically tailored for multiple-input multipleoutput space division multiple access(MIMO-SDMA)systems toward 6G *** approach aims to effectively mitigate the impact of imperfect channel estimation by leveraging the channel fluctuation mean square error(MSE)for reconstructing a highly accurate precoding matrix at the ***,we introduce a simplified receiver structure that eliminates the need for equalization,resulting in reduced interference and notable enhancements in overall system *** conduct both computer simulations and experimental tests to validate the efficacy of our proposed *** results reveals that the proposed NLP scheme offers significant performance improvements,making it particularly well-suited for the forthcoming 6G wireless.

关键词： MIMO-SDMA nonlinear precoding Tomlinson-Harashima precoding(THP) vector perturbation(VP)