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Optimizing stem cells for cardiac repair:Current status and new frontiers in regenerative cardiology

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world Journal of Stem Cells 2017年第1期9卷 9-25页

作者： Shant Der Sarkissian Thierry lévesque Nicolas Noiseux Department of Surgery Faculté de Médecine Université de MontréalMontrealQC H3C 3J7Canada Facultéde Médecine Universitéde MontréalMontrealQC H3C 3J7Canada

Cell therapy has the potential to improve healing of ischemic heart, repopulate injured myocardium and restore cardiac function. The tremendous hope and potential of stem cell therapy is well understood, yet recent trials involving cell therapy for cardiovascular diseases have yielded mixed results with inconsistent data thereby readdressing controversies and unresolved questions regarding stem cell efficacy for ischemic cardiac disease treatment. These controversies are believed to arise by the lack of uniformity of the clinical trial methodologies, uncertainty regarding the underlying reparative mechanisms of stem cells, questions concerning the most appropriate cell population to use, the proper delivery method and timing in relation to the moment of infarction, as well as the poor stem cell survival and engraftment especially in a diseased microenvironment which is collectively acknowledged as a major hindrance to any form of cell therapy. Indeed, the microenvironment of the failing heart exhibits pathological hypoxic, oxidative and inflammatory stressors impairing the survival of transplanted cells. Therefore, in order to observe any significant therapeutic benefit there is a need to increase resilience of stem cells to death in the transplant microenvironment while preserving or better yet improving their reparative functionality. Although stem cell differentiation into cardiomyocytes has been observed in some instance, the prevailing reparative benefits are afforded through paracrine mechanisms that promote angiogenesis, cell survival, transdifferentiate host cells and modulate immune responses. Therefore, to maximize their reparative functionality, ex vivo manipulation of stem cells through physical, genetic and pharmacological means have shown promise to enable cells to thrive in the postischemic transplant microenvironment. In the present work, we will overview the current status of stem cell therapy for ischemic heart disease, discuss the most recurring c

关键词： Stem cell Regenerative medicine Cellular cardiomyoplasty Preconditioning Myocardial infarction Heart failure Viability Paracrine activity Transplantation Pharmaco-optimizer

THE BAND STRUCTURE AND wORK FUNCTION OF TRANSPARENT CONDUCTINg AlUMINUM AND MANgANESE CO-DOPED ZINC OXIDE FIlMS

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Acta Metallurgica Sinica(English letters) 2005年第3期18卷 356-362页

作者： H.T.Cao Z.l.Pei X.B.Zhang J.gong C.Sun l.S.wen DivisionofSurfaceEngineeringofMaterials InstituteofMetalResearchTheChineseAcademyofSciencesShenyang110016China DivisionofSurfaceEngineeringofMaterials InstituteofMetalResearchTheChineseAcademyofSciencesShenyang110016China／／ShenyangResearchCenterforInterfacialMaterialsShenyang110016China

Al and Mn co-doped-ZnO films have been prepared at room temperature by DC reacti ve magnetron sputtering technique. The optical absorption coefficient, apparent and fundamental band gap, and work function of the films have been investigated using optical spectroscopy, band structure analyses and ultraviolet photoelectro n spectroscopy (UPS). ZnO films have direct allowed transition band structure, w hich has been confirmed by the character of the optical absorption coefficient. The apparent band gap has been found directly proportional to N2/3, showing that the effect of Burstein-Moss shift on the band gap variations dominates over the many-body effect. with only standard cleaning protocols, the work function of ZnO: (Al, Mn) and ZnO: Al films have been measured to be 4.26 and 4.21eV, respec tively. The incorporation of Mn element into the matrix of ZnO, as a relatively deep donor, can remove some electrons from the conduction band and deplete the d ensity of occupied states at the Fermi energy, which causes a loss in measured p hotoemission intensity and an increase in the surface work function. Based on th e band gap and work function results, the energy band diagram of the ZnO: (Al, M n) film near its surface is also given.

关键词： transparent conducting oxide film band gap UPS work function

grass Cover Influences Hydrophysical Parameters and Heterogeneity of water Flow in a Sandy Soil

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Pedosphere 2011年第6期21卷 719-729页

作者： l.lICHNER D.J.ElDRIDgE K.SCHACHT N.ZHUKOVA l.HOlKO M.íR J.PECHO Institute of Hydrology Slovak Academy of Sciences Department of Environment Climate Change and water School of BiologicalEarth and Environmental SciencesUniversity of New South Wales geography Department Ruhr-University BochumUniversitaetsstrasse M.Nodia Institute of geophysics Institute of Hydrodynamics Academy of Sciences of the Czech Republic Institute of Atmospheric Physics Academy of Sciences of the Czech Republic

Vegetation cover has a major effect on water flow in soils. Two sites, separated by distance of about 50 m, were selected to quantify the influence of grass cover on hydrophysical parameters and heterogeneity of water flow in a sandy soil emerging during a heavy rain following a long hot, dry period. A control soil （pure sand） with limited impact of vegetation or organic matter was obtained by sampling at 50 cm depth beneath a glade area, and a grassland soil was covered in a 10 cm thick humic layer and colonised by grasses. The persistence of water repellency was measured using the water drop penetration time test, sorptivity and unsaturated hydraulic conductivity using a mini disk infiltrometer, and saturated hydraulic conductivity using a double-ring infiltrometer. Dye tracer experiments were used to assess the heterogeneity of water flow, and both the modified method for estimating effective cross section and an original method for assessing the degree of preferential flow were used to quantify this heterogeneity from the images of dyed soil profiles. Most hydrophysical parameters were substantially different between the two surfaces. The grassland soil had an index of water repellency about 10 times that of pure sand and the persistence of water repellency almost 350 times that of pure sand. water and ethanol sorptivities in the grassland soil were 7% and 43%, respectively, of those of the pure sand. Hydraulic conductivity and saturated hydraulic conductivities in the grassland soil were 5% and 16% of those of the pure sand, respectively. Dye tracer experiments revealed a stable flow with ＂air-draining＂ condition in pure sand and well-developed preferential flow in grassland soil, corresponding to individual grass tussocks and sinai! micro-depressions. The grassland soil was substantially more water repellent and had 3 times the degree of preferential flow compared to pure sand. The results of this study reinforce our view that the consequences of any change in

关键词： dye tracing grassland soil hydrophobicity infiltration preferential flow

Therapeutic neovascularization promoted by injectable hydrogels

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Bioactive Materials 2018年第4期3卷 389-400页

作者： Amrita Pal Brent l.Vernon Mehdi Nikkhah School of Biological and Health Systems Engineering Arizona State UniversityArizona 85281USA

The aim of therapeutic neovascularization is to repair ischemic tissues via formation of new blood vessels by delivery of angiogenic growth factors,stem cells or expansion of pre-existing *** efficient neovascularization,controlled release of growth factors is particularly necessary since bolus injection of molecules generally lead to a poor outcome due to inadequate retention within the injured *** this regard,injectable hydrogels,made of natural,synthetic or hybrid biomaterials,have become a promising solution for efficient delivery of angiogenic factors or stem and progenitor cells for in situ tissue repair,regeneration and *** review article will broadly discuss the state-of-the-art in the development of injectable hydrogels from natural and synthetic precursors,and their applications in ischemic tissue repair and wound *** will cover a wide range of in vitro and in vivo studies in testing the functionalities of the engineered injectable hydrogels in promoting tissue repair and *** will also discuss some of the injectable hydrogels that exhibit self-healing properties by promoting neovascularization without the presence of angiogenic factors.

关键词： Injectable hydrogels Neovascularization Tissue regeneration Angiogenic factors Cell-therapy

Sparse Approximations of the Schur Complement for Parallel Algebraic Hybrid Solvers in 3D

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Numerical Mathematics(Theory,Methods and Applications) 2010年第3期3卷 276-294页

作者： l.giraud A.Haidar Y.Saad Joint INRIA-CERFACS lab-42 AV.Coriolis 31057ToulouseFrance Department of Computer Science University of TennesseeKnoxvilleTN37996USA. Department of Computer Science and Engineering University of MinnesotaMinneapolisMN55455USA

In this paper we study the computational performance of variants of an algebraic additive Schwarz preconditioner for the Schur complement for the solution of large sparse linear *** earlier works,the local Schur complements were computed exactly using a sparse direct *** robustness of the preconditioner comes at the price of this memory and time intensive computation that is the main bottleneck of the approach for tackling huge *** this work we investigate the use of sparse approximation of the dense local Schur *** approximations are computed using a partial incomplete lU *** a numerical calculation is the core of the multi-level incomplete factorization such as the one implemented in pARMS. The numerical and computing performance of the new numerical scheme is illustrated on a set of large 3D convection-diffusion problems;preliminary experiments on linear systems arising from structural mechanics are also reported.

关键词： Hybrid direct/iterative solver domain decomposition incomplete/partial factorization Schur approximation scalable preconditioner convection-diffusion large 3D problems parallelscientific computing High Performance Computing.

Analytic time-of-flight positron emission tomography reconstruction: threedimensional case

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Visual Computing for Industry,Biomedicine,and Art 2020年第1期3卷 39-52页

作者： gengsheng l.Zeng Ya li Qiu Huang Department of Engineering Utah Valley University800 West University ParkwayOremUT 84058USA Department of Radiology and Imaging Sciences University of Utah729 Arapeen DriveSalt Lake CityUT 84108USA Department of Mathematics Utah Valley University800 West University ParkwayOremUT 84058USA School of Biomedical Engineering Shanghai Jiaotong UniversityShanghai 200240China

In a positron emission tomography(PET)scanner,the time-of-flight(TOF)information gives us rough event position along the line-of-response(lOR).Using the TOF information for PET image reconstruction is able to reduce image *** state-of-the-art TOF PET image reconstruction uses iterative *** study introduces an analytic TOF PET algorithm that focuses on three-dimensional(3D)*** proposed algorithm is in the form of backprojection filtering,in which the backprojection is performed first by using a time-resolution profile function,and then a 3D filter is applied to the backprojected *** the list-mode data,the backprojection is carried out in the event-by-event fashion,and the timing resolution determined weighting function is used along the projection *** simulations are carried out to verify the feasibility of the proposed algorithm.

关键词： Positron emission tomography Time-of-flight Analytic reconstruction

Metabolic alterations and vulnerabilities in hepatocellular carcinoma

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gastroenterology Report 2021年第1期9卷 1-13,I0001页

作者： Daniel gTenen li Chai Justin l.Tan Cancer Science Institute of Singapore National University of SingaporeSingapore Harvard Stem Cell Institute Harvard Medical SchoolBostonMAUSA Department of Pathology Brigham&Women’s HospitalHarvard Medical SchoolBostonMAUSA Experimental Drug Development Centre Agency for ScienceTechnology and Research(A*STAR)Singapore genome Institute of Singapore Agency for ScienceTechnology and Research(A*STAR)Singapore

liver cancer is a serious *** is ranked as the cancer with the second highest number of cancer-related deaths *** carcinoma(HCC),which arises from transformed hepatocytes,is the major subtype of liver *** accounts for 85%of total liver-cancer *** important aspect of HCC that has been actively studied is its *** the liver as the primary site of numerous metabolic processes in the body,it has been shown that the metabolism of HCC cells is highly dysregulated compared to that of normal *** is therefore crucial to understand the metabolic alterations caused by HCC and the underlying mechanisms for these *** deeper understanding will allow diagnostic and therapeutic advancements in the treatment of *** this review,we will summarize the current literature in HCC metabolic alterations,induced vulnerabilities,and potential therapeutic interventions.

关键词： hepatocellular carcinoma(HCC) metabolism metabolic vulnerability targeted therapy

The data acquisition algorithm designed for the SiPM-based detectors of gECAM satellite

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Radiation Detection Technology and Methods 2022年第1期6卷 70-77页

作者： Y.Q.liu K.gong X.Q.li X.Y.wen Z.H.An C.Cai Z.Chang g.Chen C.Chen Y.Y.Du M.gao R.gao D.Y.guo J.J.He D.J.Hou Y.g.li C.Y.li g.li l.li X.F.li M.S.li X.H.liang X.J.liu F.J.lu H.lu B.Meng w.X.Peng F.Shi X.l.Sun H.wang J.Z.wang Y.S.wang H.Z.wang X.wen S.Xiao S.l.Xiong Y.B.Xu Y.P.Xu S.Yang J.w.Yang Q.B.Yi Fan Zhang D.l.Zhang S.N.Zhang C.Y.Zhang C.M.Zhang Fei Zhang X.Y.Zhao Y.Zhao X.Zhou Key laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China Physics and Space Science College China West Normal UniversityNanchong 637002China

Background The gravitational wave High-energy Electromagnetic Counterpart All-sky Monitor(gECAM)consists of 2 microsatellites,each of which contains 25 gRD(laBr3)detectors and 8 CPD(plastic scintillator)*** silicon photomultiplier(SiPM)array is used to read each *** output signal of these detectors with SiPM array is very special and challenging to *** this study,a novel data acquisition(DAQ)algorithm for these detectors is designed and implemented,and the content of the output event packet is *** and Conclusion The performances,including the event acquisition efficiency of this DAQ algorithm,are extensively verified through experimental *** the on-ground and in-flight tests,this algorithm has excellent performance despite the very limited resources and short development time of gECAM mission.

关键词： Silicon photomultiplier Digital waveform processing Data acquisition

genetic factors that affect nonalcoholic fatty liver disease: A systematic clinical review

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world Journal of gastroenterology 2016年第29期22卷 6742-6756页

作者： Tyler J Severson Siddesh Besur Herbert l Bonkovsky Department of gastroenterology and Hepatology Wake Forest University NC Baptist Medical Center Abdominal Transplant Program Aurora St Luke’s Medical Center

AIM: To investigate roles of genetic polymorphisms in non-alcoholic fatty liver disease (NAFlD) onset, severity, and outcome through systematic literature ***: The authors conducted both systematic and specific searches of PubMed through December 2015 with special emphasis on more recent data (from 2012 onward) while still drawing from more historical data for background. we identified several specific genetic polymorphisms that have been most researched and, at this time, appear to have the greatest clinical significance on NAFlD and similar hepatic diseases. These were further investigated to assess their specific effects on disease onset and progression and the mechanisms by which these effects ***: we focus particularly on genetic polymorphisms of the following genes: PNPlA3, particularly the p. I148M variant, TM6SF2, particularly the p. E167K variant, and on variants in FTO, lIPA, IFNλ4, and iron metabolism, specifically focusing on HFE, and HMOX-1. we discuss the effect of these genetic variations and their resultant protein variants on the onset of fatty liver disease and its severity, including the effect on likelihood of progression to cirrhosis and hepatocellular carcinoma. while our principal focus is on NAFlD, we also discuss briefly effects of some of the variants on development and severity of other hepatic diseases, including hepatitis C and alcoholic liver disease. These results are briefly discussed in terms of clinical application and future potential for personalized ***: Polymorphisms and genetic factors of several genes contribute to NAFlD and its end results. These genes hold keys to future improvements in diagnosis and management.

关键词： genetic polymorphisms Non-alcoholic fatty liver disease Non-alcoholic steatohepatitis PNPlA3 TM6SF2 FTO Cirrhosis Iron metabolism