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Randomized controlled trials - mechanistic studies of testosterone and the cardiovascular system

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Asian Journal of Andrology 2018年第2期20卷 120-130页

作者： t Hugh Jones Daniel m Kelly Robert Hague Centre for Diabetes and Endocrinology Barnsley Hospital NHS Foundation Trust Barnsley UK Academic Unit of Diabetes Endocrinology and Metabolism Department of Oncology and Metabolism University of Sheffield Medical School Sheffield UK Biomedical Research Centre Sheffield Hallam University Sheffield UK

testosterone deficiency is common in men with cardiovascular disease （CVD）, and randomized placebo-controlled trials （RCts） have reported beneficial effects of testosterone therapy on exercise-induced cardiac ischemia in chronic stable angina, functional exercise capacity, maximum oxygen consumption during exercise （VO2m,x） and muscle strength in chronic heart failure （CHF）, shortening of the Q-t interval, and improvement of some cardiovascular risk factors. testosterone deficiency is associated with an adverse CV risk profile and mortality. Clinical and scientific studies have provided mechanistic evidence to support and explain the findings of the RCts. testosterone is a rapid-onset arterial vasodilator within the coronary circulation and other vascular beds including the pulmonary vasculature and can reduce the overall peripheral systemic vascular resistance. Evidence has demonstrated that testosterone mediates this effect on vascular reactivity through calcium channel blockade （L-calcium channel） and stimulates potassium channel opening by direct nongenomic mechanisms. testosterone also stimulates repolarization of cardiac myocytes by stimulating the ultra-rapid potassium channel-operated current. testosterone improves cardiac output, functional exercise capacity, VO2m=x and vagally mediated arterial baroreceptor cardiac reflex sensitivity in CHF, and other mechanisms. Independent of the benefit of testosterone on cardiac function, testosterone substitution may also increase skeletal muscle glucose metabolism and enhance muscular strength, both factors that could contribute to the improvement in functional exercise capacity may include improved glucose metabolism and muscle strength. testosterone improves metabolic CV risk factors including body composition, insulin resistance, and hypercholesterolemia by improving both glucose utilization and lipid metabolism by a combination of genomic and nongenomic actions of glucose uptake and utilization expression of the

关键词： cardiovascular testosterone testosterone replacement

DAmAGE mECHANISmS OF INCONEL 738LC UNDERCREEP-FAtIGUE LOADING CONDItIONS

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Acta metallurgica Sinica(English Letters) 1998年第6期11卷 470-476页

作者： m.Yamamoto t.Ogata Central Research Inst of Electric Power Industry Tokyo Japan

In order to investigate creep-fatigue life characteristics of InConel 738LC, fatigue and creep-fatigue tests were carried out at 850 degree C. Significant life reduction to 30% to 50% of normal fatigue life, occurred when a strain hold period was introduced at the minimum compressive strain. test results show that the degree of life reduction does not depend on the scale of hold time. to clarify the creep-fatigue damage mechanisms under creep-fatigue loading, in-situ SEm observations were carried out during the tests. In the tensile strain hold test, multi-site grain boundary cracking was observed from the beginning of the test. On the other hand, only a single main crack was observed in the compressive strain hold test. the crack propagates in an intergranular manner, and it is different from the features observed under cyclic fatigue conditions. through the detailed observations, it was found that the grain boundary sliding damage occurs at most surface grain boundaries. (Edited author abstract) 5 Refs.

关键词： superalloy creep-fatigue grain boundary sliding

Heat transfer Augmentation in Developing Flow through a Ribbed Square Duct

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Journal of thermal Science 2006年第3期15卷 251-256页

作者： Khan R K Ali m.A.t Akhanda m.A.R Principal Polytechnic InstitutePotuakhaliBangladesh Department of mechanical Engineering Bangladesh University of Engineering and Technology(BUET)DhakaBangladesh Department of mechanical and Chemical Engineering Islamic University of technology(IUt) OIC Gazipur-1704DhakaBangladesh

An experimental study is conducted to investigate the heat transfer augmentation in developing turbulent flow through a ribbed square duct. the duct is made of 16ram thick bakelite sheet. the bottom surface of the ribbed wall having rib pitch to height ratio of 10 is heated by passing a c current to the heater placed under it. the uniform heating is controlled using a digital temperature controller and a variac. the results of ribbed duct are compared with the results of a smooth duct under the same experimental conditions. It is observed that the heat transfer augmentation in ribbed duct is better than that of the smooth duct. At Re=5.0× 10^4 , the mean temperature of air flowing through the ribbed duct increases by 2.45 percent over the smooth duct, whereas in the fibbed duct Nusselt number increases by 15.14 percent than that of the smooth duct with a 6 percent increase in pressure drop.

关键词： heat transfer square duct developing flow turbulent promoters

Effects of varying Alx moles on structure and luminescence properties of ZnAl_(x)O_(1.5x+1):0.1 mol%tb^(3+)nanophosphors prepared using citrate sol-gel method

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Journal of Rare Earths 2023年第3期41卷 358-364,I0002页

作者： V.m.maphiri L.t.melato m.R.mhlongo t.t.Hlatshwayo t.E.motaung L.F.Koao S.V.motloung Department of Physics Sefako Makgatho Health Science UniversityP.O.Box 94Medunsa0204South Africa Department of mathematics Non Destructive Testing and PhysicsVaal University of TechnologyAndries Potgieter BlvdVanderbijlpark1900South Africa Department of Physics University of PretoriaPretoria0002South Africa Department of Chemistry School of Science in the College of Science Engineering and TechnologyUniversity of South AfricaPreller StreetMuckleneuk RidgeCity of TshwaneP.O Box 392UNISA 0003South Africa Department of Chemistry Sefako Makgatho Health Science UniversityP.O.Box 94Medunsa0204South Africa Department of Physics University of the Free State(Qwaqwa Campus)Private Bag X13Phuthaditjhaba 9866South Africa Department of Chemical and Physical Sciences Walter Sisulu UniversityMthathaSouth Africa

Un-doped and ZnAl_(x)O_(1.5x+1):0.1 mol%tb^(3+)(ZAOt)nano-powders were synthesized via citrate sol-gel *** AIx moles were varied in the range of 0.25≤x≤*** X-ray powder diffraction(XRD)data reveal that for xthe prepared samples crystal structure consists of mixed phases of the cubic ZnAl_(2)O_(4) and hexagonal ZnO phases,while for x>1.5 the structure consists of single phase of cubic ZnAl_(2)O_(4).the Raman and Fourier-trans form infrared(FtIR)vibrational spectroscopy show the presence of vibrations emanating ZnAl_(2)O_(4) *** electron microscopy(SEm)and transmission electron microscopy(tEm)show the presence of irregular sphere at x>2.0 attributed to ZnAl_(2)O_(4).the photoluminescence(PL)spectroscopy reveals emissions from both the host and tb^(3+)*** from tb^(3+)are observed at 382,414,439,458 nm and 489,545,585,621 nm,which were attributed to the^(5)D_(3)→^(7)F_(6,5,4,2) and ^(5^)D_(4)→^(7)F_(6,5,4,3),*** results confirm that the tb^(3+)occupation site depends on the Alx *** International Commission on Illumination(CIE)colour chromaticity shows that the emission colour can be tuned from blue to green by varying the AIx moles.

关键词： Citrate sol-gel ZnAl_(2)O_(4)/ZnO tb^(3+)-doped Al_(x)moles Photoluminescence Rare earths

Simple operated multipurpose temperature control cryostat

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第5期8卷 793-796页

作者： ABBAS t.A. OmAR m.S. Department of Physics College of Science University of SalahaddinArbilIraqi KurdistanIraq

A suitable simple optical cryostat for optical, magneto-optical, electrical and thermo-electrical measurements was designed. It is suitable for use in a magnetic pool gap as narrow as less than 1 cm. throughout a long period of time, the heat diffusion process of the cryostat can be easily operated at slow increase in sample temperature in a range 1.25 K/min at 200 K that will be reduced gradually to 0.66 K at room temperature. Liquid nitrogen was used to cool down the temperature. During the operation, the change in the measured energy gap of a semiconductor sample and other physical parameters resulting from the change of temperature can be corrected through the temperature coefficient of that parameter at the corresponding temperature. the cryostat was successfully used for all experiments mentioned above to measure the properties of a single crystal of GaP (Gallium Phosphate) semiconductor.

关键词： Optical cryostat Electrical cryostat magneto-optical cryostat

New Exact Solutions of a Relativistic toda Lattice System

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Chinese Physics Letters 2012年第9期29卷 53-56页

作者： m.t.Darvishi F.Khani Department of mathematics Razi UniversityKermanshah 67149Iran

We study the application of the exp-function method to solve a relativistic toda lattice *** reduce the original equation into a convenient form,a suitable transformation is used so that the so-called exp-function method can be *** using the homogeneous balance principle and some further analysis,we succeed in calculating some exact analytic solutions.

关键词： convenient exact calculating

Radiolarian and Planktic Foraminifera Biostratigraphy of the Early Albian Organic Rich Beds of Fahdene Formation,Northern tunisia

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Journal of Earth Science 2014年第1期25卷 45-63页

作者： m Ben Fadhel t Zouaghi A Amri m Ben Youssef Département de Géologie Faculté des Sciences de Gafsa-Campus Universitaire Sidi Ahmed Zarrouk–2112 Département des Géoressources CERTE–Technopole de Borj Cédria

the lower part of Fahdene Formation outcropping in northeastern tunisia is repre- sented by pelagic sequences and characterized by an important siliciclastic fraction that includes ra- diolarian and organic-rich beds of Allam member. Litho-biostratigraphic analysis based on planktic foraminifera and radiolaria shows that deposition of organic-rich beds of Allam member is confined to the microhedbergella rischi Zone through the lower part of ticinella primula Zone. Age diagnostic radiolaria recovered from these beds has been identified to constrain a direct age of black shale depo- sition. the assemblages can be correlated with the radiolarian biochronozone U.A.10-11 indicating an Early Albian to early middle Albian in age. Radiolarian assemblages composed of species characteris- tic of U.A.10 biochronozone （A. montisserei, D. gracilis） are associated with radiolarian taxa belonging to Costata Zone （U.A.9 Pseudoeucyrtis hanni and thanarla pseudodecora）, which can be correlated with Dercourt member in the Ionian Zone and Paquier level of the Vocontian Basin （southeast of France）. Biostratigraphic and abundance curves analysis has demonstrated significant diversification of cryptocephalic Nassellaria and Archaeodictyomitrae, probably adapted to eutrophic conditions that characterized the Aptian-Albian transition. Ecological conditions may have governed the stratigraphic range of many cosmopolitan taxa （i.e., Pseudodictyomitrae lodogaensis） compared with stratigraphic distributions schemes reported from other domains. the timing of black shales deposition was dia- chronic due to local geodynamic conditions and upwelling currents distribution. the Allam black shales are correlative with the oceanic anoxic event OAElb which is characterized by the widespread of supraregionnally organic-rich beds in the mediterranean tethys basins across the Aptian-Albian transition.

关键词： northeastern tunisia Albian Allam member black shale radiolaria planktic foraminifera.

Surface modification of stratum corneum for drug delivery and skin care by microplasma discharge treatment

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Plasma Science and technology 2019年第6期21卷 1-8页

作者： J KRIStOF t AOSHImA m BLAJAN K SHImIZU Graduate School of Science and technology Shizuoka University 432-8561 Hamamatsu Japan Department of Electrical and Electronic Engineering Shizuoka University 432-8561 Hamamatsu Japan Organization for Innovation and Social Collaboration Shizuoka University 432-8561 Hamamatsu Japan

Human skin is the largest organ and also the main barrier that prevents foreign substances from entering the *** surface properties of the skin are relevant for transdermal drug delivery and *** micropig skin is used as a substitute for human skin.A microplasma electrode is used for surface modification of the skin epidermal layer of the Yucatan *** dielectric barrier discharge has a thin dielectric as a barrier (~50 μm) and a frequency of 25 *** surface properties of the epidermal layer were characterized by the measurement of the contact angle of the water *** effects of different gases such as air,nitrogen,oxygen,helium or argon were *** change of the contact angle is temporal and it is returned to its initial state after several *** the gases used for plasma ignition,oxygen and argon were the most effective for skin *** distance of the skin from the electrode and the treatment time played a crucial roles in the increasing water contact *** of surface atomic concentration were determined by x-ray photoelectron *** microplasma treatment,the oxygen and nitrogen concentration increased at the skin surface.

关键词： microplasma contact angle skin stratum corneum XPS

Comprehension of functional support by enculturated chimpanzees Pan troglodytes

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Current Zoology 2011年第4期57卷 429-440页

作者： Anna m. YOCOm Sarah t. BOYSEN Department of Psychology The Ohio State University Columbus OH 43210 USA

Studies of causal understanding of tool relationships in captive chimpanzees have yielded disparate findings, particularly those reported by Povinelli ＆ colleagues （2000） for tool tasks by laboratory chimpanzees. the present set of experiments tested nine enculturated chimpanzees on three versions of a support task, as described by Povinelli （2000）, during which food re- wards were presented in different experimental configurations. In Experiment 1, stimulus pairs included a choice between a cloth with a reward on the upper right comer or with a second reward off the cloth, adjacent to a comer, with the second pair comprised of a cloth with food on the upper right comer, and a second cloth with the reward on the substrate, partially covered. All subjects were successful with both test conditions in Experiment 1. In a second study, the experimental choices included one of two possi- ble correct options, paired with one of three incorrect options, with the three incorrect choices all involving varying degrees of perceptual containment. All nine chimpanzees scored significantly above chance across all six conditions. In Experiment 3, four unique conditions were presented, combining one of two possible correct choices with one of two incorrect choices. Six of the subjects scored significantly above chance across the four conditions, and group performance on individual conditions was also significant. Superior performance was demonstrated by female subjects in Experiment 3, similar to sex differences in tool use previously reported for wild chimpanzees and some tool tasks in captive chimpanzees. the present results for Experiments 2 ＆ 3 were significantly differed from those reported by Povinelli et al. （2000） for laboratory-born, peer-reared chimpanzees. One contribution towards the dramatic differences between the two study populations may be the significant rearing and housing differences of the chimpanzee groups. One explanation is that under conditions of enculturat

关键词： Chimpanzees Comparative cognition tool use Causality