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Caloric restriction-mimetics for the reduction of heart failure risk in aging heart: with consideration of gender-related differences

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Military Medical Research 2023年第1期10卷 113-133页

作者： Lei Pang xi Jiang xin Lian Jie Chen Er-Fei Song Lei-Gang Jin Zheng-Yuan xia hai-chun Ma Yin Cai Department of Anesthesiology the First Hospital of Jilin UniversityChangchun 130021China Health Promotion Center the First Hospital of Jilin UniversityChangchun 130021China Department of Urology the First Hospital of Jilin UniversityChangchun 130021China Henry Fok School of Biology and Agriculture Shaoguan UniversityShaoguan 512000GuangdongChina Department of Metabolic and Bariatric Surgery Jinan University First Affiliated HospitalGuangzhou 510630China Department of Medicine LKS Faculty of Medicinethe University of Hong KongHong KongChina State Key Laboratory of Pharmaceutical Biotechnology LKS Faculty of Medicinethe University of Hong KongHong KongChina Department of Anesthesiology Affiliated Hospital of Guangdong Medical UniversityZhanjiang 524000GuangdongChina Department of Health Technology and Informatics the Hong Kong Polytechnic UniversityHong KongChina

The literature is full of claims regarding the consumption of polyphenol or polyamine-rich foods that offer some protection from developing cardiovascular disease(CVD). This is achieved by preventing cardiac hypertrophy and protecting blood vessels through improving the function of endothelium. However, do these interventions work in the aged human hearts? Cardiac aging is accompanied by an increase in left ventricular hypertrophy, along with diastolic and systolic dysfunction. It also confers significant cardiovascular risks for both sexes. The incidence and prevalence of CVD increase sharply at an earlier age in men than women. Furthermore, the patterns of heart failure differ between sexes, as do the lifetime risk factors. Do caloric restriction(CR)-mimetics, rich in polyphenol or polyamine, delay or reverse cardiac aging equally in both men and women? This review will discuss three areas:(1) mechanisms underlying age-related cardiac remodeling;(2) gender-related differences and potential mechanisms underlying diminished cardiac response in older men and women;(3) we select a few polyphenol or polyamine rich compounds as the CRmimetics, such as resveratrol, quercetin, curcumin, epigallocatechin gallate and spermidine, due to their capability to extend health-span and induce autophagy. We outline their abilities and issues on retarding aging in animal hearts and preventing CVD in humans. We discuss the confounding factors that should be considered for developing therapeutic strategies against cardiac aging in humans.

关键词： Cardiovascular disease Cardiac aging Caloric restriction Gender difference Caloric restriction-mimetics Dietary compounds Clinical application

High-mobility patternable MoS_(2) percolating nanofilms

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Nano Research 2021年第7期14卷 2255-2263页

作者： xiangxiang Gao Jun Yin Gang Bian hai-Yang Liu Chao-Peng Wang xi-xi Pang Jian Zhu School of Materials Science and Engineering National Institute for Advanced MaterialsNankai UniversityTianjin 300350China Tianjin Key Laboratory of Metal and Molecule-Based Material Chemistry Tianjin Key Laboratory for Rare Earth Materials and ApplicationsNankai UniversityTianjin 300350China

Fabrication of large-area and uniform semiconducting thin films of two-dimensional(2D)materials is paramount for the full exploitation of their atomic thicknesses and smooth surfaces in integrated *** addition to elaborate vapor-based synthesis techniques for the wafer-scale growth of 2D films,solution-based approaches for high-quality thin films from the liquid dispersions of 2D flakes,despite underdeveloped,are alternative cost-effective ***,we present layer-by-layer(LbL)assembly as an effective approach to obtaining scalable semiconducting films of molybdenum disulfide(MoS_(2))for field-effect transistors(FETs).LbL assembly is achieved by coordinating electrochemically exfoliated MoS_(2) with cationic poly(diallyldimethylammonium chloride)(PDDA)through electrostatic *** PDDA/MoS_(2) percolating nanofilms show controlled and self-limited growth on a variety of substrates,and are easily patterned through lift-off *** gel gated FETs are fabricated on these MoS_(2) nanofilms,and they show mobilities of 9.8 cm^(2)·V^(−1)·s^(−1),on/off ratios of 2.1×10^(5) with operating voltages less than 2 *** annealing temperature in the fabrication process can be as low as 200℃,thereby permitting the fabrication of flexible FETs on polyethylene terephthalate *** LbL assembly technique holds great promise for the large-scale fabrication of flexible electronics based on solution-processed 2D semiconductors.

关键词： layer-by-layer assembly molybdenum disulfide nanofilms solution-processed electronics field-effect transistors

Quantitative gradient estimates for harmonic maps into singular spaces

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Science China Mathematics 2019年第11期62卷 2371-2400页

作者： Hui-chun Zhang xiao Zhong xi-Ping Zhu Department of Mathematics Sun Yat-sen UniversityGuangzhou 510275China Department of Mathematics and Statistics University of HelsinkiHelsinki F7-00014Finland

In this paper, we show the Yau’s gradient estimate for harmonic maps into a metric space(X, dX)with curvature bounded above by a constant κ(κ 0) in the sense of Alexandrov. As a direct application,it gives some Liouville theorems for such harmonic maps. This extends the works of Cheng(1980) and Choi(1982) to harmonic maps into singular spaces.

关键词： harmonic maps Bochner formula CAT(κ)-spaces Liouville theorem

Shear Fracture of Advanced High Strength Steels

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Journal of Iron and Steel Research International 2014年第10期21卷 938-944页

作者： Sheng HUANG Yi-xi ZHAO chun-feng HE State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Shanghai Key Laboratory of Digital Manufacture for Thin-walled Structures Shanghai Jiao Tong University

Failure experiments were carried out through a stretch-bending test system for advanced high strength steels, i.e. dual-phase （DP） steels and martensitic steels （MS）. The die radius in this system was designed from 1 to 15 mm to investigate the failure mode under different geometries. Two failure modes were observed during the ex- periments. As a result, critical relative radii （the ratio of inner bending radius R to sheet thickness t） for DP590 and DP780 steels were obtained. The stretch-bending tests of DP980 display some trends unlike DP590 and DP780 steels, and curve of DP980 in different thicknesses does not coincide well. High blank holder force exhibits more possibility of shear fracture tendency than low blank holder force. The unique character of high strength martensitic steel （1500MS） is that no shear fracture is found especially over small bending radius （R =2 mm） under the same experi- mental conditions. Microstructure analysis indicates that there are obviously elongated grains on shear fracture sur- face. It shows smaller diameter and shallower depth of the dimples than the necking failure.

关键词： advanced high strength steel shear fracture critical R/t blank holder force microstructure

Nutrient Budget and Soil Nutrient Status in Greenhouse System

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Agricultural Sciences in China 2010年第6期9卷 871-879页

作者： YU hai-ying LI Ting-xuan ZHANG xi-zhou College of Resources and Environmental Sciences Sichuan Agricultural University Ya'an 625014 P.R. China School of Geography Beijing Normal University Beijing 100875 P.R.China

This paper is based on nutrient budget and its effects on soil nutrient status in typical greenhouse system in China to provide a basis for raising the utilization rate of fertilizers and maintaining the sustainable development of agriculture in the *** investigating the management of 18 representative greenhouses in Shouguang,Shandong Province,China,and analyzing both the greenhouse and open field soil samples,the soil nutrient budget and the trend of nutrient accumulation and translocation in soils were thus *** results under greenhouse system showed that the average annual inputs of N,P2O5 and K2O were 4 088,3 655 and 3 437 kg ha-1,*** total inputs of N,P2O5 and K2O provided by chemical fertilizers which are the main source of soil nutrient were 63,61 and 66%,*** utilization rates of N,P2O5 and K2O were only 24,8,46% and the input ratio among N,P2O5 and K2O （1：0.9：0.8） was quite different from the uptake ratio （1：0.3：1.4）.It had caused the excess of N,P2O5 and K2O in the soil,and the theoretical surpluses were 3 214,3 401 and 2 322 kg ha-1,respectively,for N,P2O5 and *** level of the organic matter,total nitrogen,nitrate nitrogen,available phosphorus,and available potassium was increased substantially,and their maximum level was observed in the topsoil （0-20 cm） with an average value being 1.4,1.9,21.2,5.4,and 3.7 times higher than that of the open field soil,*** greenhouse soils showed leaching of the nutrients,especially NO3- which would cause a potential risk to the quality of groundwater in the *** is necessary to apply more organic manure and provide nutrients according to the crop requirements and soil fertility as it could not only produce high crop yield,but also be beneficial to balance the soil nutrient and improve the utilization rate of ***,there would be no significant surplus of nutrients which may leach out of soil to contaminate the environment.

关键词： greenhouse system fertilization nutrient budget soil nutrient status

Fluidization characteristics of different sizes of quartz particles in the fluidized bed

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Petroleum Science 2016年第3期13卷 584-591页

作者： Zi-Jian Wang Jun Tang chun-xi Lu State Key Laboratory of Heavy Oil Processing China University of Petroleum(Beijing)

Fluidization characteristics of quartz particles with different sizes are experimentally investigated in a fluidized bed with an inner diameter of 300 mm and height of 8250 *** show that the average solid holdup increases with the increase in superficial gas velocity and the decrease in initial solid holdup in the dense zone of the fluidized *** average cross-sectional solid holdup decreases with increasing bed height and superficial gas *** bed expansion coefficient increases with the increase in superficial gas velocity and the decrease in solid *** of average solid holdup,average cross-sectional solid holdup and bed expansion coefficient are also established and *** correlations can provide guidelines for better understanding of the fluidization characteristics.

关键词： Fluidization characteristic Solid holdup Axial average section solid holdup Bed expansion coefficient

Existence of Three Positive Solutions for Some Second-Order M-Point Boundary Value Problems

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Acta Mathematicae Applicatae Sinica 2008年第2期24卷 253-264页

作者： Liu Yang chun-fang Shen xi-ping Liu Department of Mathematics Hefei Teacher's College Heifei 230061 China College of Science University of Shanghai for Science and Technology Shanghai 200093 China

By using fixed-point theorems, some new results for multiplicity of positive solutions for some second order m-point boundary value problems are *** associated Green＇s function of these problems are also given.

关键词： second order m-point boundary value problem, positive solution cone, fixed point

Bifurcations of Limit Cycles in A Perturbed Quintic Hamiltonian System with Six Double Homoclinic Loops

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Acta Mathematicae Applicatae Sinica 2008年第2期24卷 313-328页

作者： Yong-xi Gao Yu-hai Wu Li-xin Tian Department of Mathematics Jiang Su University Zhenjiang 212013 China

This paper concerns with the number and distributions of limit cycles of a quintic subject to a seven-degree perturbation. With the aid of numeric integral computation provided by Mathematica 4.1, at least 45 limit cycles are found in the above system by applying the method of double homoclinic loops bifurcation, Hopf bifurcation and qualitative analysis. The four configurations of 45 limit cycles of the system are also shown. The results obtained are useful to the study of the weakened 16th Hilbert Problem.

关键词： limit cycles the Hilbert's 16th problem the double homoclinic loops stability Poincare-Bendixsontheorem

Integrating outlier filtering in large margin training

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第5期12卷 362-370页

作者： xi-chuan ZHOU hai-bin SHEN Jie-ping YE College of Communication Engineering Chongqing University Chongqing 400044 China School of Electrical Engineering Zhejiang University Hangzhou 310027 China Dcpartment of Computer Science and Engineering Arizona State University Tempe 85281 USA

Large margin classifiers such as support vector machines (SVM) have been applied successfully in various classification ***,their performance may be significantly degraded in the presence of *** this paper,we propose a robust SVM formulation which is shown to be less sensitive to *** key idea is to employ an adaptively weighted hinge loss that explicitly incorporates outlier filtering in the SVM training,thus performing outlier filtering and classification *** resulting robust SVM formulation is *** first relax it into a semi-definite programming which admits a global *** improve the efficiency,an iterative approach is *** have performed experiments using both synthetic and real-world *** show that the performance of the standard SVM degrades rapidly when more outliers are included,while the proposed robust SVM training is more stable in the presence of outliers.

关键词： Support vector machines Outlier filter Semi-definite programming Multi-stage relaxation