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Preserving fertility in the hypogonadal patient： an update

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Asian Journal of Andrology 2015年第2期17卷 197-200,I0006,I0007页

作者： Ranjith Ramasamy Joseph m Armstrong Larry i Lipshultz Department of Urology Baylor Collegesssss of Medicine Houston TX USA.

An increasing number of young and middle-aged men are seeking treatment for symptoms related to deficient levels of androgens （hypogonadism） including depression, loss of libido, erectile dysfunction, and fatigue. The increase in prevalence of testosterone supplementation in general and anabolic steroid-induced hypogonadism specifically among younger athletes is creating a population of young men who are uniquely impacted by the testicular end-organ negative consequences of exogenous steroid use. Exogenous testosterone therapy can alter the natural regulation of the hypothalamic-pituitary-gonadal axis leading to impaired spermatoganesis with azoospermia being a serious possible result, thus rendering the individual infertile. For men of reproductive age who suffer from hypogonadal symptoms, preservation of fertility is an important aspect of their treatment paradigm. Treatment with human chorionic gonadotropin （hCG） has shown the ability not only to reverse azoospermia brought on by testosterone supplementation therapy but also to help maintain elevated intratesticular testosterone levels. in addition, selective estrogen receptor modulators, often used with hCG have been shown both to elevate total testosterone levels and to maintain spermatogenesis in hypogonadal men.

关键词： human chorionic gonadotropin selective estrogen receptor modulators spermatogenesis testosterone supplementation therapy

isomeric pair 95m,g Nb in the photonuclear reactions on natmo at the bremsstrahlung end-point energy of 38–93 meV

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Chinese Physics C 2023年第12期47卷 64-72页

作者： i.S.Timchenko O.S.Deiev S.m.Olejnik S.m.Potin V.A.Kushnir V.V.mytrochenko S.A.Perezhogin V.A.Bocharov institute of Physics Slovak Academy of SciencesSK-84511 BratislavaSlovakia National Science Center"Kharkov institute of Physics and Technology" 1Akademichna St.61108KharkivUkraine CNRS/iJCLAB 15 Rue Georges Clemenceau Str.Orsay91400France

The ^(nat)mo(γ,xnp)^(95m,g)Nb photonuclear reaction was studied using the electron beam from the NSC KiPT linear accelerator *** experiment was performed using the activation and off-line γ-ray spectrometric *** experimental isomeric yield ratio(iR) was determined for the reaction products ^(95m,g)Nb at the bremsstrahlung end-point energy E_(γmax) range of 38-93 *** obtained values of iR are in satisfactory agreement with the results of other studies and extend the range of previously known *** theoretical values of the yields Y_(m,g)(E_(γmax)) and the iR for the isomeric pair ^(95m,g)Nb from the ^(nat)mo(γ,xnp) reaction were calculated using the partial cross-sections σ(E) from the TALYS1.95 code for six different level density *** the investigated range of E_(γmax),the theoretical dependence of iR on energy was confirmed-the iR smoothly increases with increasing *** comparison showed a noticeable difference(more than 3.85 times) in the experimental iR relative to all theoretical estimates.

关键词： photonuclear reactions natmo isomeric pair 95m gNb isomeric yield ratio reaction yield bremsstrahlung end-point energy of 38–93 meV activation and off-lineγ-ray spectrometric technique TALYS1.95 level density model GEANT4.9.2.

Hybridization between microstructure and magnetization improvement in lead and RE co-doped BiFeO_3

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Journal of Rare Earths 2016年第5期34卷 495-506页

作者： m.A.Ahmed S.F.mansour S.i.El-Dek m.m.Karamany materials Science Lab.(1) Physics Dept.Faculty of ScienceCairo University Physics Department Faculty of ScienceZagazig University materials Science and Nanotechnology Dept. Faculty of Post Graduate Studies for Advanced SciencesBeni-Suef University Basic Science Dept. Faculty of EngineeringBritish University in Egypt

The crystal structure,magnetic and electrical properties of Bi（0.96）Pb（0.04） FeO3 and Bi（0.92）Pb（0.04）RE（0.04）FeO3（RE=La,Sm,Dy and Yb）polycrystalline samples were prepared by the flash autocombustion technique.X-ray diffraction（XRD）measurements show that the rare-earth doped compositions crystallized in rhombohedral symmetry of space group R3 *** undoped sample consisted needle shape particles while rare earth substitution preferred platelet like particles as clarified from high resolution transmission electron microscopy（HRTEm）.morphological features were examined using field emission scanning electron microscopy（FESEm）.magnetization measurements showed that Yb^3＋ samples possessed the highest room temperature saturation magnetization while when Bi^3＋ ions were substituted by La^3＋ ions,a smaller mS（0.28 emu/g）was *** coexistence of ferroelectric and magnetic transitions was detected using DSC and χm,indicating the multiferroic characteristics of Bi（0.92）Pb（0.04）RE（0.04）FeO3 *** Néel temperature shifted upwards with decreasing the ionic radius of rare earth *** correlation was established between microstructure,morphology and magnetic properties in view of the contribution of magnetocrystalline and shape anisotropy in the magnetic parameters values.

关键词： BiFeO3 multiferroic rare earths anisotropy dielectric conductivity Neel temperature

Thermal Spray Coating of Tungsten for Tokamak Device

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Plasma Science and Technology 2006年第2期8卷 164-167页

作者：蒋显亮 F. GiTZHOFER m.i. BOULOS institute of Surface and Coatings Technology Central South University Changsha 410083 China Plasma Technology Research Center University of Sherbrooke Sherbrooke J1K 2R1Canada

Thermal spray, such as direct current （d.c.） plasma spray or radio frequency induced plasma spray, was used to deposit tungsten coatings on the copper electrodes of a tokamak device. The tungsten coating on the outer surface of one copper electrode was formed directly through d.c. plasma spraying of fine tungsten powder. The tungsten coating/lining on the inner surface of another copper electrode could be formed indirectly through induced plasma spraying of coarse tungsten powder. Scanning electron microscopy （SEm） was used to examine the cross section and the interface of the tungsten coating. Energy Dispersive Analysis of X-ray （EDAX） was used to analyze the metallic elements attached to a separated interface. The influence of the particle size of the tungsten powder on the density, cracking behavior and adhesion of the coating is discussed. it is found that the coarse tungsten powder with the particle size of 45-75μm can be melted and the coating can be formed only by using induced plasma. The coating deposited from the coarse powder has much higher cohesive strength, adhesive strength and crack resistance than the coating made from the fine powder with a particle size of 5μm.

关键词： tokamak device copper electrode thermal spray tungsten coating tungsten/copper interface

Effect of Hydrostatic Pressure on interband Transitions in Coupled Quantum Wires

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Chinese Physics Letters 2007年第4期24卷 1058-1061页

作者： E. Kasapoglu m. Günes i Sokmen Department of Physics Cumhuriyet University 58140 Sivas Turkey Department of Physics Dokuz Eylül University 35160 izmir Turkey

We calculate the exciton binding energy and interband optical absorption in a rectangular coupled quantum wire under the hydrostatic pressure in the effective-mass approximation, using the variational approach. it is found that the interband optical absorption strongly depend on the hydrostatic pressure and the coupling parameter, and that the magnitude of the absorption coefficient for the HH1-E1 transition in the coupled quantum wire is larger than that of the single quantum wire.

关键词： APPLiED ELECTRiC-FiELD SHALLOW DONOR imPURiTiES WELL WiRES BiNDiNG-ENERGiES OPTiCAL-ABSORPTiON mAGNETiC-FiELD GAAS TEmPERATURE DEPENDENCE THRESHOLD

Effect of (Ba_(0.6)Sr_(0.4))TiO_3(BST) Doping on Dielectric Properties of CaCu_3Ti_4O_(12)(CCTO)

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Journal of materials Science & Technology 2012年第12期28卷 1137-1144页

作者： i. Norezan A.K. Yahya m.K. Talari Faculty of Applied Sciences Universiti Teknologi MARAShah Alam Selangor Malaysia

The effect of （Ba（0.6）Sr（0.4））TiO3（BST） addition on dielectric properties of CaCu3Ti4O（12）（CCTO） ceramic was investigated. Ceramic samples with the chemical formula （1-x）CaCu3Ti4O（12）＋ x（Ba（0.6）,Sr（0.4））TiO3 （x=0, 0.05, 0.1, and 0.2） were synthesized from high purity oxide powders by the conventional solid-state synthesis method. X-ray diffraction （XRD） analysis showed the existence of BST as a secondary phase alongside CCTO. Scanning electron microscopy （SEm） investigation showed a slight decrease in grain size of doped CCTO samples. Density measurements showed that porosity content increased with increasing BST addition indicating low densification due to high melting point secondary phase addition. Dielectric constant of undoped CCTO （x=0） showed lack of stability with frequency which dropped drastically between 104 and 105Hz and accompanied by high dielectric loss. Addition of BST into CCTO caused the dielectric constant to slightly decrease but improved stability with frequency compared to the undoped sample. The decrease in dielectric constant of doped CCTO samples was suggested to be partly due to the decrease in average grain size and increase in porosity with BST addition. Nevertheless, a high value of dielectric constant was still maintained around ～104 range for all doped samples. The dielectric loss （tanδ） of all BST-doped samples was lower than that of pure CCTO sample at the frequency range of 103 to 105 Hz probably due to the increase of grains boundary resistivity. The activation energy of grains boundary （E（gb）） showed higher values as compared to the activation energy of grains （Eg ） for all samples and conforms to the internal barrier layer capacitor （iBLC） model.

关键词： CaCu3Ti4O(12)(CCTO) Dielectric properties (Ba(0.6)Sr(0.4))TiO3(BST)

Electroanalytical tools to investigate the divalent state of Eu(Ⅲ) and Nd(Ⅲ) ions in non-aqueous medium

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Journal of Rare Earths 2012年第4期30卷 392-396页

作者： Jignasu P mehta Himanshu m Pandya Kahan i Pandya Department of Chemistry DST-FIST sponsored Department Mahatma Gandhi Campus Bhavnagar University

The divalent state of Ln（iii） ions has attracted much interest because of their ability to serve isomorphously in many biological system of divalent Ca（ii） ion. Therefore, present paper deals with the study of divalent state of Eu（iii） and Nd（iii） ions in non-aqueous medium. in present study, cyclic voltammetry and chronopotentiometry were utilized to establish the divalent state of Eu（iii） and Nd（iii） ions. The cyclic voltammetric technique showed two-step reduction process at cathode for both Ln（iii） ions under specified experimental conditions and chronopotentiometric method also showed two different transition times （r）. Looking to the shape of cyclic voltammogram we calculated het- erogeneous forward rate constant （K^fh, cm/s） and diffusion coefficient （D, cm2/s） for both ions, which suggested that sweep rate had great ef- fect on the shape of cyclic voltammogram of Eu（iii） and Nd（iii） ions. The result of chronopotentiometry also suggested that stable divalent states of Eu（iii） and Nd（iii） ions existed with chronopotentiogram with two distinct transition times. The diffusion coefficients （D, cm2/s） were calculated from Sand equation. The diffusion coefficients of both techniques were compared and the results suggested that the system at electrode surface was changing from being reversible to irreversible.

关键词： Eu(ili) and Nd(iii) ions non-aqueous medium cyclic-voltammetry chronopotentiomentry rare earths

Plasma spray forming of tungsten coatings on copper electrodes

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中国有色金属学会会刊：英文版 2004年第5期14卷 835-839页

作者：蒋显亮 F.Gitzhofer m.i.Boulos School of materials Science and Engineering Central South University Changsha 410083 China Plasma Technology Research Center University of Sherbrooke Sherbrooke J1K 2R1 Canada

Both direct current dc plasma and radio frequency induction plasma were used to deposit tungsten coatings on copper electrodes. Fine tungsten powder with mean particle size of 5 μm and coarse tungsten powder with particle size in the range from 45 μm to 75 μm were used as plasma spray feedstock. it is found that dc plasma is only applicable to spray the fine tungsten powder and induction plasma can be used to spray both the coarse powder and the fine powder. The tungsten coating deposited by the induction plasma spraying of the coarse powder is extremely dense. Such a coating with an interlocking structure and an integral interface with the copper substrate demonstrates high cohesion strength and adhesion strength.

关键词：等离子喷涂钨铜电解工艺联锁结构金属

Simulation and Analysis of multisoliton Generation Using a PANDA Ring Resonator System

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Chinese Physics Letters 2011年第10期28卷 95-98页

作者： i.S.Amiri A.Afroozeh m.Bahadoran Department of Physics Science and Research BranchIslamic Azad UniversityTehranIran

A novel system of multisoliton generation using nonlinear equations of the propagating signals is *** system uses a PANDA ring resonator incorporated with an add/drop filter *** resonant conditions,the intense optical fields known as multisolitons can be generated and propagated within a Kerr-type nonlinear *** present simulation results show that multisolitons can be controlled by using additional Gaussian pulses input into the add port of the PANDA *** the soliton pulse in the microring device,a balance should be achieved between dispersion and nonlinear *** output signals from the PANDA ring resonator are input into the add/drop filter *** signals can be filtered by using the add/drop filter system,in which multi dark and bright solitons can be *** this work multi dark and bright solitons with an FWHm and an FSR of 425 pm and 1.145 nm are generated,respectively,where the Gaussian pulse with a central wavelength of 1.55µm and power of 600 mW is input into the system.

关键词： resonator system soliton