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Calculations of the transmitted gamma photons through infinite slabs

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nuclear Science and Techniques 2018年第4期29卷 114-120页

作者： Asuman Ayd?n Department of Physics Faculty of Arts and SciencesBal?kesir University Cagis Campus

The intensity and number of transmitted multiple scattered photons are calculated for 0.123, 0.320, 0.511,0.662, and 1.115 Me V gamma photons normally incident on slabs of carbon, aluminum, iron, copper, water, muscle,bone, and concrete with thicknesses varying from 1 to 10 mean free paths. The dependence of the transmission probability and energy distribution on the incident energy and material are examined. In general, the obtained results show good agreement with the other values calculated by the Monte Carlo method.

关键词： Monte Carlo simulation Gamma photons Energy distribution Transmission probability

Androgen synthesis inhibitors in the treatment of castration-resistant prostate cancer

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Asian Journal of Andrology 2014年第3期16卷 387-400页

作者： Mark n Stein Rutgers Cancer Institute of new Jersey Department of Surgery Rutgers Robert Wood Johnson Medical SchoolNew Brunswick New Jersey USA. Department of Medicine Department of Surgery Rutgers Robert Wood Johnson Medical SchoolNew Brunswick New Jersey USA. Section of Urologic Oncology Department of Surgery Rutgers Robert Wood Johnson Medical SchoolNew Brunswick New Jersey USA.

Suppression of gonadal testosterone synthesis represents the standard first line therapy for treatment of metastatic prostate cancer. However, in the majority of patients who develop castration-resistant prostate cancer （CRPC）, it is possible to detect persistent activation of the androgen receptor （AR） through androgens produced in the adrenal gland or within the tumor itself. Abiraterone acetate was developed as an irreversible inhibitor of the dual functional cytochrome P450 enzyme CYP17 with activity as a 17（^-hydroxylase and 17,20-1yase. CYP17 is necessary for production of nongonadal androgens from cholesterol. Regulatory approval of abiraterone in 2011, based on a phase III trial showing a significant improvement in overall survival （OS） with abiraterone and prednisone versus prednisone, represented proof of principle that targeting AR is essential for improving outcomes in men with CRPC. Inhibition of 17α-hydroxylase by abiraterone results in accumulation of upstream mineralocorticoids due to loss of cortisol-mediated suppression of pituitary adrenocorticotropic hormone （ACTH）, providing a rationale for development of CYP17 inhibitors with increased specificity for 17,20-1yase （orteronel, galeterone and VT-464） that can potentially be administered without exogenous corticosteroids. In this article, we review the development of abiraterone and other CYP17 inhibitors; recent studies with abiraterone that inform our understanding of clinical parameters such as drug effects on quality-of-life, potential early predictors of response, and optimal sequencing of abiraterone with respect to other agents; and results of translational studies providing insights into resistance mechanisms to CYP17 inhibitors leading to clinical trials with drug combinations designed to prolong abiraterone benefit or restore abiraterone activity.

关键词： androgen synthesis castration-resistant prostate cancer treatment

EXPOnEnTIAL DECAY FOR A VISCOELASTICALLY DAMPED TIMOSHEnKO BEAM

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Acta Mathematica Scientia 2013年第2期33卷 505-524页

作者： n. TATAR King Fahd University of Petroleum and Minerals Department of Mathematics & StatisticsDhahran 31261Saudi Arabia

Of concern is a viscoelastic beam modelled using the Timoshenko theory. It is well-kimwn that the system is exponentially stable if the kernel in the memory term is sub- exponential. That is, if the product of the kernel with an exponential function is a summable function. In this article we address the questions： What if the kernel is tested against a different function （say Gamma） other than the exponential function？ Would there still be stability？ In the affirmative, what kind of decay rate we get？ It is proved that for a non- decreasing function ＂Gamma＂ whose ＂logarithmic derivative＂ is decreasing to zero we have a decay of order Gamma to some power and in the case it decreases to a different value than zero then the decay is exponential.

关键词： Arbitrary decay memory term relaxation function Timoshenko beam vis-coelasticity

nO-ARBITRAGE SYMMETRIES

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Acta Mathematica Scientia 2022年第4期42卷 1373-1402页

作者： Iván DEGAnO Sebastián FERRAnDO Alfredo GOnZáLEZ Departamento de Matemática.Facultad de Ciencias Exactas y naturales Universidad Nacional de Mar del Plata 7600Argentina Department of Mathematics Ryerson University350 Victoria St.TorontoOntario M5B 2K3Canada

The no-arbitrage property is widely accepted to be a centerpiece of modern financial mathematics and could be considered to be a financial law applicable to a large class of(idealized) *** paper addresses the following basic question:can one characterize the class of transformations that leave the law of no-arbitrage invariant?We provide a geometric formalization of this question in a non probabilistic setting of discrete time-the so-called trajectorial *** paper then characterizes,in a local sense,the no-arbitrage symmetries and illustrates their meaning with a detailed *** context makes the result available to the stochastic setting as a special case.

关键词： no arbitrage symmetry convexity preserving maps non-probabilistic markets

Lattice thermal conduction in cadmium arsenide

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Chinese Physics B 2022年第11期31卷 424-430页

作者： R F Chinnappagoudra M D Kamatagi n R Patil n S Sankeshwar Department of Physics S.S.Government First Grade CollegeNargund-582207KarnatakaIndia Research Resource Centre Visvesvaraya Technological UniversityBelagavi-590018KarnatakIndia Department of Physics B V B College of Engineering and TechnologyHubliKarnataka 80031India Department of Physics&Electronics CHRIST(Deemed to be University)Bangalore-560029KarnatakaIndia

Lattice thermal conductivity(LTC)of cadmium arsenide(Cd_(3)As_(2))is studied over a wide temperature range(1–400 K)by employing the Callaway *** acoustic phonons are considered to be the major carriers of heat and to be scattered by the sample boundaries,disorder,impurities,and other phonons via both Umklapp and normal phonon *** calculations of LTC of Cd_(3)As_(2)bring out the relative importance of the scattering *** systematic analysis of recent experimental data on thermal conductivity(TC)of Cd_(3)As_(2)samples of different groups,presented in terms of LTC,κL,using a nonlinear regression method,reveals good fits to the TC data of the samples considered for Tnd suggests a value of 0.2 for the Gruneisen *** is,however,found that for T>100 K the inclusion of the electronic component of TC,κe,incorporating contributions from relevant electron scattering mechanisms,is needed to obtain good agreement with the TC data over the wide temperature *** detailed investigations of TC of Cd_(3)As_(2)are required to better understand its suitability in thermoelectric and thermal management devices.

关键词： dirac semimetals Cd_(3)As_(2) thermal conductivity phonon scattering

Assessments on slope instabilities triggered by engineering excavations near a small settlement(Turkey)

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Journal of Mountain Science 2018年第1期15卷 114-129页

作者： TUnCAY Ergün Department of Geological Engineering Hacettepe University

In this study,the mechanisms of slope instabilities triggered by engineering excavations at location of a planned tunnel portal in the northwest region of Turkey were assessed,and stability of the current slopes which has impacts on safety of a settlement(village)and agricultural fields was *** the first stage of the study,in order to identify the geological units and structural properties of the sedimentary rocks in the area,to clarify the mechanisms of instabilities and to characterize discontinuity and rock mass properties field works were *** this content,geotechnical boreholes,geophysical explorations between the boreholes,line surveys to explore discontinuity properties,preparation of slope profiles using topographical techniques and sampling of rock blocks and discontinuity planes were *** the second stage,laboratory tests were carried out on the samples to determine the geomechnical properties of the slope forming materials and ***,back analyses of the instabilities were made to assess the responsible shear strength parameters of the geological units during failures by considering laboratory shear test results *** on the backanalyses of the failures,the strength properties of the slope debris were estimated,and it has been clarified that the residual shear strength properties are the factors controlling slip mechanism along the *** the stability analyses,it is understood that a further instability along the mass or bedding planes in the failed and redesigned area are not expected,if the current slope geometry is not ***,safety factor calculated for the slope in the debris is 1.1 which is well below the recommended value in the *** minimum safety factor for currently stable slopes which were cut at the eastern part of the failed area is 1.22 which is also less than that suggested in *** remedial measures such as mini-pile or slope flattening are suggested af

关键词： Slope instability Back-analysis Remedial measures

Inn/InGan quantum dot electrochemical devices:new solutions for energy and health

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national Science Review 2017年第2期4卷 184-195页

作者： Richard ntzel South China Academy of Advanced Optoelectronics South China Normal University L-nESS and Dipartimento di Scienza dei Materiali Università di Milano-Bicocca

A review is given of the exceptional electrochemical performance of epitaxial Inn/InGan quantum dots(QDs) as photoelectrodes for solar hydrogen generation by water spliting, as biosensor transducers and as anion-selective electrodes, and they are also evaluated as supercapacitor electrodes. he performance is benchmarked against the best performances of other reported materials and nanostructures. A model based on the unique interplay of surface and quantum properties is put forward to understand the boost of catalytic activity and anion selectivity interlinking quantum nanostructure physics with electrochemistry and catalysis. Of equal impact is the direct growth on cheap Si substrates without any bufer layers, allowing novel device designs and integration with Si technology. his makes the Inn/InGan QDs viable, opening up new application ields for Ⅲ-nitride semiconductors.

关键词： quantum dot solar hydrogen biosensor ion-selective electrode supercapacitor Inn InGan

novel approach for evaluation of service reliability for electricity customers

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Science China(Technological Sciences) 2009年第9期52卷 2585-2590页

作者： JIAnG John n School of Electrical and Computer Engineering University of OklahomaNorman OK 73019 USA

Understanding reliability value for electricity customer is important to market-based reliability management. This paper proposes a novel approach to evaluate the reliability for electricity customers by using indifference curve between economic compensation for power interruption and service reliability of electricity. Indifference curve is formed by calculating different planning schemes of network expansion for different reliability requirements of customers, which reveals the information about economic values for different reliability levels for electricity customers, so that the reliability based on market supply demand mechanism can be established and economic signals can be provided for reliability management and enhancement.

关键词： power systems electricity market reliability customers’ outage cost indifference curve

Optimum cutting speed of block-cutting machines in natural stones for energy saving

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Journal of Central South University 2012年第5期19卷 1234-1239页

作者： n.Bilim Department of Mining Engineering Seluk UniversityKonyaTurkey

Energy consumption of block-cutting machines represents a major cost item in the processing of travertines and other natural stones. Therefore, determining the optimum sawing conditions for a particular stone is of major importance in the natural stone-processing industry. An experimental study was carried out utilizing a fully instrumented block-cutter to investigate the sawing performances of five different types of travertine blocks during cutting with a circular diamond saw. The sawing tests were performed in the down-cutting mode. Performance measurements were determined by measuring the cutting speed and energy consumption. Then, specific energy was determined. The one main cutting parameter, cutting speed, was varied in the investigation of optimum cutting performance. Furthermore, some physico-mechanical properties of file travertine blocks were determined in the laboratory. As a result, it is found that the energy consumption （specific energy） of block cutting machines is highly affected by cutting speed. It is determined that specific energy value usually decreases when cutting speed increases. When the cutting speed is higher than the determined value, the diamond saw can become stuck in the travertine block; this situation can be a problem for the block-cutting machine. As a result, the optimum cutting speed obtained for the travertine mines examined is approximately 1.5-2.0 m/min.

关键词： cutting speed travertine block cutting machine specific energy natural stone energy saving