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Apoptosis and DNA damage in human spermatozoa

Asian Journal of Andrology 2011年第1期13卷 36-42页

作者： r john Aitken Adam J Koppers ArC Centre of Excellence in Biotechnology and Development Priority Research Centre in Reproductive Science Discipline of Biological Sciences School of Environmental and Life Sciences University of Newcastle Callaghan NSW 2308 Australia Department of Anatomy and Developmental Biology School of Biomedical Sciences Monash University Clayton VIC 3800 Australia

DNA damage is frequently encountered in spermatozoa of subfertile males and is correlated with a range of adverse clinical outcomes including impaired fertilization, disrupted preimplantation embryonic development, increased rates of miscarriage and an enhanced risk of disease in the progeny. The etiology of DNA fragmentation in human spermatozoa is closely correlated with the appearance of oxidative base adducts and evidence of impaired spermiogenesis. We hypothesize that oxidative stress impedes spermiogenesis, resulting in the generation of spermatozoa with poorly remodelled chromatin. These defective cells have a tendency to default to an apeptotic pathway associated with motility loss, caspase activation, phosphatidylserine exteriorization and the activation of free radical generation by the mitochondria. The latter induces lipid peroxidation and oxidative DNA damage, which then leads to DNA fragmentation and cell death. The physical architecture of spermatozoa prevents any nucleases activated as a result of this apoptotic process from gaining access to the nuclear DNA and inducing its fragmentation. It is for this reason that a majority of the DNA damage encountered in human spermatozoa seems to be oxidative. Given the important role that oxidative stress seems to have in the etiology of DNA damage, there should be an important role for antioxidants in the treatment of this condition. If oxidative DNA damage in spermatozoa is providing a sensitive readout of systemic oxidative stress, the implications of these findings could stretch beyond our immediate goal of trying to minimize DNA damage in spermatozoa as a prelude to assisted conception therapy.

关键词： apoptosis DNA damage oxidative stress spermatozoa

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Entropy generation in bypass transitional boundary layer flows

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Journal of Hydrodynamics 2014年第5期26卷 669-680页

作者： GEOrGE Joseph owen Landon D. XING Tao MCELIGOT Donald M. CrEPEAU john C. BUDWIG ralph S. NOLAN Kevin P. Department of Mechanical Engineering College of EngineeringUniversity of IdahoMoscowIdaho 83843USA University of Idaho Idaho FallsIdaho 83402USA University of Idaho BoiseIdaho 83702USA Imperial College London London SW7-28ZUK

The primary objective of this study is to evaluate the accuracy of using computational fluid dynamics （CFD） turbulence models to predict entropy generation rates in bypass transitional boundary layers flows under zero and adverse pressure gradients. Entropy generation rates in such flows are evaluated employing the commercial CFD software, ANSYS FLUENT. Various turbulence and transitional models are assessed by comparing their results with the direct numerical simulation （DNS） data and two recent CFD studies. A solution verification study is conducted on three systematically refined meshes. The factor of safety method is used to estimate the numerical error and grid uncertainties. Monotonic convergence is achieved for all simulations. The reynolds number based on momentum thickness, reo, skin-friction coefficient, Cf, approximate entropy generation rates, S, dissipation coefficient, Cd , and the intermittency, y, are calculated for bypass transition simulations. All reynolds averaged Navier-Stokes （rANS） turbulence and transitional models show improvement over previous CFD results in predicting onset of transition. The transition SST k - ω 4 equation model shows closest agreement with DNS data for all flow conditions in this study due to a much finer grid and more accurate inlet boundary conditions. The other rANS models predict an early onset of transition and higher boundary layer entropy generation rates than the DNS shows.

关键词： entropy generation bypass transition reynolds averaged Navier-Stokes (rANS) transitional boundary layer turbulence models

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Impact of androgen deprivation therapy on sexua function

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Asian Journal of Andrology 2012年第2期14卷 198-203页

作者： Clarisse r Mazzola john P Mulhall Sexual and reproductive Medicine Program Urology ServiceMemorial SIoan Kettering Cancer CenterNew YorkNY 10065USA

Many patients with prostate cancer for whom androgen deprivation therapy （ADT） is indicated are young and desire to remain sexually active. In such patients, the side effects of androgen therapy on sexual function can be a source of serious reduction in overall quality of life. Providing the appropriate treatment options in this patient population is therefore essential. Nevertheless, treating such patients is challenging and an understanding of the underlying mechanisms of sexual physiology and pathophysiology is crucial to optimal patient care. In this paper, we reviewed what was known regarding the effects of ADT on sexual function in animal models and we also provided a detailed review on the effects of ADT on sexual health in humans and its treatment.

关键词： androgen deprivation therapy castration ejaculation erectile dysfunction orgasm

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Populating digital earth: improving access to Chinese remote sensing data for terrestrial applications

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International Journal of Digital Earth 2014年第12期7卷 952-968页

作者： Mengxue Li john r.Townshend Department of Geographical Sciences University of MarylandCollege ParkMD 20742MarylandUSA

Global change has a significant impact on the lives of *** observation can help to better understand our earth and cope with global *** the availability of more reliable environmental data sets,digital earth is becoming a popular way to monitor the Earth and provide information to researchers and decision makers on environment protection,disaster mitigation,and social ***,accessing data with lowering costs is essential for digital ***,there are big challenges in ensuring the feasibility of access to Chinese remote sensing *** paper outlines some of the main challenges in realizing data sharing,provides an analysis of the core reasons leading to these challenges,and proposes recommendations to overcome the *** the main challenges are differences in data policy to gain access to satellite data,diverse data formats,and delivery *** major challenge for the decision makers is to define a more open policy and for the scientist the challenge is to implement these polices for the benefit of *** paper proposes that governments should adopt policies encouraging more open distribution and access to their data,in order to generate an improved digital earth with increased benefits to human society.

关键词： date policy remote sensing data sharing China

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A Survey of Language-Based Approaches to Cyber-Physical and Embedded System Development

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Tsinghua Science and Technology 2015年第2期20卷 130-141页

作者： Paul Soulier Depeng Li john r. Williams University of Hawaii Massachusetts Institute of Technology(MIT)

As computers continue to advance, they are becoming more capable of sensing, interacting, and communicating with the physical and cyber world. Medical devices, electronic braking systems in automotive applications, and industrial control systems are examples of the many Cyber-Physical Systems （CPS） that utilize these computing capabilities. Given the potential consequences of software related failures in such systems, a high degree of safety, security, and reliability is often required. Programming languages are important tools used by programmers to develop CPS. They provide a programmer with the ability to transform designs into machine code. Of equal importance is their ability to detect and avoid programming mistakes. The development of CPS has predominantly been accomplished using the C programming language. Although C is a powerful language, it lacks features present in other languages that facilitate the development of reliable systems. This has prompted research into language-based alternatives for improving program quality through the use of programming languages. This paper presents an overview of the characteristics of embedded and cyber-physical systems and the associated requirements imposed on programming languages. This is followed by a survey of relevant research into language- based methods for creating safe, reliable, and robust software for CPS.

关键词： cyber-physical systems embedded systems programming languages type systems

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Hydrodynamics and solids mixing in fluidized beds with inclined-hole distributors

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Particuology 2019年第2期17卷 19-28页

作者： Alhussain Bakhurji Xiaotao Bi john r. Grace Fluidization research Centre Department of Chemical and Biological Engineering University of British Columbia Vancouver V6TJZ3 Canada

Experimental fluidization results were compared for three gas distributors with the same opening ratio but different orifice in clinations (30,45 , and 90 ). Hydrodynamic studies were con ducted with glass beads (diameter 154p.m) to evaluate the impacts of orifice inclination and static bed depth on pressure drop, pressure drop fluctuations, bed expansion, and minimum fluidization velocity. Solids residence time distributions were determined using phosphoresce nt tracer particles (mea n diameter 76 pm), activated by ultraviolet light. The bed pressure drop was higher with the inclined-hole distributors and increased with static bed height. In a shallow bed, the inclined-hole distributors gave less expansion;however, in deep beds, the orifice angle had negligible influence on bed expansion. The minimum fluidization velocity varied with static bed height for the inclined-hole distributors and was higher for steeper angles. The turnover time estimated using bubbling-bed equations matched the experimental results well for vertical mixing. Probes and ports at the walls of the fluidization column reduced the dense-phase downward velocity by up to 40%. The tangential particle velocity was highest for the 30 -hole distributor and decreased with increasing orifice angle. Tangential mixing was described by a dispersion model;the dispersion coefficient for the inclined-hole distributors was approximately twice that for the 90 -hole distributor in a shallow bed.

关键词： Swirling fluidized bed Fluidization Solids mixing Inclined-hole distributor

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role of fecal microbiota transplant in management of hepatic encephalopathy: Current trends and future directions

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World Journal of Hepatology 2024年第1期16卷 17-32页

作者： Yash r Shah Hassam Ali Angad Tiwari David Guevara-Lazo Natalia Nombera-Aznaran Bhanu Siva Mohan Pinnam Manesh Kumar Gangwani Harishankar Gopakumar Amir H Sohail SriLakshmiDevi Kanumilli Ernesto Calderon-Martinez Geetha Krishnamoorthy Nimish Thakral Dushyant Singh Dahiya Department of Internal Medicine Trinity Health Oakland/Wayne State UniversityPontiacMI 48341United States Division of Gastroenterology and Hepatology East Carolina University/Brody School of MedicineGreenvilleNC 27858United States Department of Internal Medicine Maharani Laxmi Bai Medical CollegeJhansi 284001India Faculty of Medicine Universidad Peruana Cayetano HerediaLima 15102Peru Department of Internal Medicine John H.Stroger Hospital of Cook CountyChicagoIL 60612United States Department of Internal Medicine The University of ToledoToledoOH 43606United States Department of Gastroenterology and Hepatology University of Illinois College of Medicine at PeoriaPeoriaIL 61605United States Department of Surgery University of New MexicoAlbuquerqueNM 87106United States Department of Internal Medicine GSL Medical CollegeRajamahendravaram 533296India Department of Internal Medicine Universidad Nacional Autonoma de MexicoCiudad De Mexico 04510Mexico Department of Digestive Diseases and Nutrition University of KentuckyLexingtonKY 40536United States Division of Gastroenterology Hepatology&MotilityThe University of Kansas School of MedicineKansas CityKS 66160United States

Fecal microbiota transplantation(FMT)offers a potential treatment avenue for hepatic encephalopathy(HE)by leveraging beneficial bacterial displacement to restore a balanced gut *** prevalence of HE varies with liver disease severity and *** pathogenesis involves ammonia toxicity,gut-brain communication disruption,and *** aims to restore gut microbiota balance,addressing these ***'s efficacy has been explored in various conditions,including *** suggest that FMT can modulate gut microbiota,reduce ammonia levels,and alleviate *** has shown promise in alcohol-associated,hepatitis B and C-associated,and non-alcoholic fatty liver *** include improved liver function,cognitive function,and the slowing of disease ***,larger,controlled studies are needed to validate its effectiveness in these *** have shown cognitive improvements through FMT,with potential benefits in cirrhotic ***,trials have demonstrated reduced serious adverse events and cognitive enhancements in FMT arms compared to the standard of *** evidence is promising,challenges remain:Limited patient numbers,varied dosages,administration routes,and donor *** large-scale,controlled trials are essential to establish standardized guidelines and ensure FMT's clinical applications and *** FMT holds potential for HE management,ongoing research is needed to address these challenges,optimize protocols,and expand its availability as a therapeutic option for diverse hepatic conditions.

关键词： Hepatic encephalopathy Fecal microbiota transplant Cognitive impairment Liver cirrhosis Chronic liver disease

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Sperm cell biology： current perspectives and future prospects

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Asian Journal of Andrology 2011年第1期13卷 3-5页

作者： r john Aitken ralf r Henkel Discipline of Biological Sciences University of Newcastle Newcastle NSW 2308 Australia Department of Medical Biosdences University of the Western Cape Bellville 7535 South Africa

Major advances in biomolecular techniques as well as in the sensitivity and accuracy of mass spectrometers are transforming the scientific landscape by fueling unprecedented advances in analytical biochemistry--the ＇... 详细信息

关键词： Sperm cell biology perspectives

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Plasma amyloid-beta oligomer and phosphorylated tau:diagnostic tools for progressive Alzheimer's disease

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Neural regeneration research 2023年第11期18卷 2391-2392页

作者： Seong Soo A.An john P.Hulme Department of Bionano Technology Gachon Bionano Research InstituteGachon UniversitySeongnam-siGyeonggi-doSouth Korea

Introduction:Spanning the three stages of the Alzheimer’s disease (AD) continuum,amyloid-beta(Aβ40and Aβ42) oligomers (AβO’s) and tau protein constitute a set of biomarkers ideally suited for the non-invasive monitoring of AD (Wolgin et al.,2022).AD progression is correlated with the presence of low molecular weight oligomers and not amyloid ***,low molecular weight AβO is present in the beginning and later stages of disease even when the plaque burden becomes ***.

关键词： amyloid tau Alzheimer

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配子源性成人疾病的表观遗传机制

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Science Bulletin 2022年第17期67卷 1724-1727页

作者：丁国莲陈宾 john r.McCarrey 黄荷凤 Obstetrics and Gynecology Hospital Institute of Reproduction and DevelopmentFudan UniversityShanghai 200011China research Units of Embryo Original Diseases Chinese Academy of Medical SciencesShanghai 200030China Key Laboratory of reproductive Genetics(Ministry of Education) Department of Reproductive EndocrinologyWomen’s HospitalZhejiang University School of MedicineHangzhou 310006China Assisted reproduction Unit Department of Obstetrics and GynecologySir Run Run Shaw HospitalSchool of MedicineZhejiang UniversityKey Laboratory of Reproductive Dysfunction Management of Zhejiang ProvinceHangzhou 310016China Department of Neuroscience Developmental and Regenerative BiologyUniversity of Texas at San AntonioSan Antonio 78249USA Shanghai Key Laboratory of Embryo Original Diseases Shanghai 200030China

The events occurring before and soon after birth appear to impact an individual’s health throughout adulthood *** pioneering work of David *** studied the nutritional status of 2414 pregnant women and their offspring during the Dutch famine between 1944 and 1945,and convincingly connected undernutrition during pregnancy to the predisposition of offspring to many adult-onset diseases,including cardiovascular disease.

关键词：成人疾病 cardiovascular diseases

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