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1980—2015年间美国从事普通放射或核医学的技术人员所接受的辐射剂量趋势报告

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国际医学放射学杂志 2021年第6期 730-730页

作者： D.Villoing D.borrego D.L.Preston b.h.alexander A.Rose M.Salasky 陈皓田何博

自1950年起,随着辐射防护能力的提高,大多数从事医疗辐射工作的技术人员所受职业暴露剂量已大幅下降。然而,由于操作剂量和工作量的增加,从事核医学操作的

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Neuroinflammation revisited through the microglial lens

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Neural Regeneration Research 2025年第7期20卷 1989-1990页

作者： Renato Socodato João b.Relvas Institute of Research and Innovation in health(i3S)and Institute for Molecular and Cell biology(IbMC) University of PortoPortoPortugal Department of biomedicine Faculty of Medicine of the University of Porto(FMUP)PortoPortugal

Neuroimmunology is emerging as a pivotal field,shedding light on the intricate dialogues between the central nervous system(CNS)and the immune *** exploration is particularly significant in understanding microglia,the CNS’s innate immune cells,beyond the conventional conflation of“neuroinflammation”and“microglial activation.”This conflation has clouded the true complexity of these processes,potentially stalling scientific progress and the development of new *** challenge the long-standing perspectives that have oversimplified these interactions,advocating for a deeper exploration of the dynamic relationship between neuroinflammation and microglial *** dissecting specific molecular pathways,we aim to illuminate their elaborate roles in neuroinflammatory responses,especially in the context of Alzheimer’s disease(AD).here,neuroinflammation is not merely a passive observer or a direct antagonist but a complex agent in the disease’s *** article calls for a significant paradigm shift towards an integrative,multi-omics approach to *** such a comprehensive framework is crucial for advancing our understanding of neuroinflammatory conditions and paving the way for targeted therapeutic strategies for brain diseases.

关键词： inflammation simplified activation

Phase Formation and Magnetic Properties of Nanocomposite Nd-Fe-b Adjusted by Small Amount of Dy and Co

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Journal of Rare Earths 2004年第z2期22卷 89-94页

作者： T S Jang T W Lim h S Aum D h Lee M b Kim Division of Materials and Chemical Engineering Sun Moon UniversityKorea Division of Materials and Chemical EngineeringSun Moon UniversityKorea Division of Mechanical EngineeringSun Moon University 100 Kalsan LiTangjung MyonAsan CityChoongnam 336-708Korea Division of Materials and Chemical EngineeringSun Moon UniversityKorea Division of Materials and Chemical EngineeringSun Moon UniversityKorea

In order to improve and stabilize the magnetic properties of nanocomposite Nd2Fe14b/α-Fe magnetic alloys by a compositional adjustment, small amount of Dy and/or Co was added to Nd9Fe84b7 alloys. DTA analysis on the amorphous of the alloys took place as the soft magnetic phases were crystallized, and then the hard magnetic Nd2Fe14b was precipitated from them. While α-Fe and a metastable 1:7 (TbCu7-type) phase were formed simultaneously in Dy and Co-free alloys, they were crystallized separately at different temperatures after Dy or Co was added. This phase separation occurred more clearly in the Dy-treated alloys and the other soft magnetic phase Fe3b was also stabilized by Dy and/or Co. The 1: 7 phase that was stabilized by Dy and/or Co was not eliminated at 700 ℃, decreasing magnetic properties of the alloys. It was eventually disappeared above 725 ℃, but Fe3b was not eliminated even at 750 ℃ when Dy was added more than 0.5 at% or Co was added more than 2.0 at%. Amount of Nd2Fe14b in the alloys tended to increase as Dy addition increased,whereas Co addition did not lead to any appreciable change in the ratio of α-Fe and Nd2Fe14b. Moreover, Dy addition apparently increased coercivity of an alloy while Co addition had a beneficial effect on remanence. The grains in the Dytreated alloys were usually finer than those in the Co-treated alloys. The grain size of both α-Fe and Nd2Fe14b in the alloys exhibiting mr ≥ 0.72 was in the range of 20 ～ 40 nm or even larger 50 nm, which is larger than the theoretical optimum size ( ～ 10 nm). Typical magnetic properties obtained from a Nd7.5Dy1.5Fe82.5Co1.5b7 alloy annealed for 12 min at 725 ℃were ihc=4.85 kOe, br= 11.32 kG, (bh)max = 15.73 MGOe, and mr=0.73.

关键词： nanocomposite Nd-Fe-b magnetic properties remanence coercivity

Analysis of the X-ray emission of Ob stars II: b stars

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Research in Astronomy and Astrophysics 2019年第8期19卷 143-150页

作者： Elizaveta Ryspaeva alexander Kholtygin Crimean Astrophysical Observatory NauchnyCrimeaRussia Saint-Petersburg State University Saint-PetersburgRussia Institute of Astronomy Russian Academy of SciencesRussia

This paper is the second part of an investigation into the mechanism for the origin of X-rays in early-type stars. Archival X-ray observations of 25 b stars, obtained by the XMM-Newton satellite, are analysed. We check two hypotheses on the origin of X-ray emission: the Magnetically Confined Wind Shock Model(MCWS) and Pollock’s paradigm. For all studied stars, the mean ratio of the half widths at half maximum to the terminal velocities appears to be R ≈ 0.15-0.20 in contradiction to Pollock’s hypothesis that R ≈ 0.5. We checked three possible consequences of the MCWS model: correlations between the hardness of the X-ray spectra for b stars and terminal wind velocities, mass loss rates and magnetic *** was shown that such correlations are marginal or even absent both for magnetic and non-magnetic b stars.

关键词： stars:early-type stars:spectra:X-ray

SIMPLE COMPUTING OF ThE CUSTOMER LIFETIME VALUE:A FIXED LOCAL-OPTIMAL POLICY APPROACh

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Journal of Systems Science and Systems Engineering 2014年第4期23卷 439-459页

作者： Julio b.Clempner alexander S.Poznyak Center for Economics Management and Social Research Department of Control Automatics Center for Research and Advanced Studies

In this paper,we present a new method for finding a fixed local-optimal policy for computing the customer lifetime *** method is developed for a class of ergodic controllable finite Markov *** propose an approach based on a non-converging state-value function that fluctuates（increases and decreases） between states of the dynamic *** prove that it is possible to represent that function in a recursive format using a one-step-ahead fixed-optimal ***,we provide an analytical formula for the numerical realization of the fixed local-optimal *** also present a second approach based on linear programming,to solve the same problem,that implement the c-variable method for making the problem computationally *** the end,we show that these two approaches are related：after a finite number of iterations our proposed approach converges to same result as the linear programming *** also present a non-traditional approach for ergodicity *** validity of the proposed methods is successfully demonstrated theoretically and,by simulated credit-card marketing experiments computing the customer lifetime value for both an optimization and a game theory approach.

关键词： Customer lifetime value optimization optimal policy method linear programming ergodic controllable Markov chains asynchronous games

A new rat model of portal hypertension induced by intraportal injection of microspheres

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World Journal of Gastroenterology 1998年第1期4卷 71-74页

作者： LI Xiang-Nong IS benjamin b alexander Department of Liver Surgery Affiliated Hospital Xuzhou Medical College Xuzhou 221002 China Department of Surgery King's Coll. Sch. of Med. and Dent. London United Kingdom Department of Liver Surgery Affiliated Hospital Xuzhou Medical College China Xuzhou Medical College China beijing Medical University China Department of Surgery King's College School and Dentistry United Kingdom Department of Liver Surgery Affiliated Hospital Xuzhou Medical College Xuzhou 221002 50 Jiaheqian Street China

IM To produce a new rat model of portal hypertension by intraportal injection of microspheres.METhODS Measured aliquots of single or differentsized microspheres (15, 40, 80μm) were injected into the portal vein to block intrahepatic portal radicals. The resultant changes in arterial, portal, hepatic venous and splenic pulp pressures were monitored. The liver and lungs were excised for histological examination.RESULTS Portal venous pressure was elevated from basal value of 089-102 kPa to a steadystate of 198-319 kPa following the sequential injections of single or differentsized microspheres, with a markedly lowered mean arterial pressure. however, a smalldose injection of 80μm microspheres (18×105) produced a steadystate portal venous pressure of 253±017 kPa, and all rats showed normal arterial pressures. In addition, numerous microspheres were found in the lungs in all experimental groups.CONCLUSION Portal hypertension can be reproduced in rats by intraportal injection of microspheres at a small dose of 80μm (18×105). Intrahepatic portalsystemic shunts probably exist in the normal rat liver..

关键词： portal vein hypertension,portal disease model,animal latex microsphere

Resistance to receptor tyrosine kinase inhibition in cancer： molecular mechanisms and therapeutic strategies

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Frontiers of Medicine 2015年第2期9卷 134-138页

作者： Peter b. alexander Xiao-Fan Wang Department of Pharmacology and Cancer biology Duke University Medical Center Durham NC 27710 USA

Drug resistance is a major factor that limits the efficacy of targeted cancer therapies. In this review, we discuss the main known mechanisms of resistance to receptor tyrosine kinase inhibitors, which are the most prevalent class of targeted therapeutic agent in current clinical use. here we focus on bypass track resistance, which involves the activation of alternate signaling molecules by tumor cells to bypass inhibition and maintain signaling output, and consider the problems of signaling pathway redundancy and how the activation of different receptor tyrosine kinases translates into intracellular signal transduction in different cancer types. This information is presented in the context of research strategies for the discovery of new targets for pharmacological intervention, with the goal of overcoming resistance in order to improve patient outcomes.

关键词： targeted therapy drug resistance receptor tyrosine kinases cancer

Transformation of the TiNi Alloy Microstructure and the Mechanical Properties Caused by Repeated b2-b190' Martensitic Transformations

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Acta Metallurgica Sinica(English Letters) 2015年第10期28卷 1230-1237页

作者： Anna Churakova Dmitry Gunderov alexander Lukyanov Niklas Nollmann Institute of Molecule and Crystal Physics RAS Ufa State Aviation Technical University Institute of Materials Physics University of Münster

The influences of thermal cycling treatment in the temperature range of b2-b19 martensitic transformations（-150 to 150 °C） on the Ti Ni alloy structure and properties were studied. Different states named the initial coarse-grained（CG） state, the ultrafine-grained（UFG） state after ECAP（with a grain size of 200 nm）, the state after ECAP and cold upsetting by 30% were considered. The results show that the microhardness and the strength increase in all the three *** to the XRD analysis, a more significant increment in the dislocation density, resulting from thermal cycling, is observed in the UFG alloy than in the CG alloy.

关键词： Thermal cycling TiNi alloy Equal-channel angular pressing Martensitic transformation

Non-relativistic scattering amplitude for a new multi-parameter exponential-type potential

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Chinese Physics b 2016年第8期25卷 21-25页

作者： Yazarloo b h Mehraban h hassanabadi h Physics Department Semnan University Physics Department Shahrood University of Technology

In this paper, we study the scattering properties of s-wave Schrdinger equation for the multi-parameter potential,which can be reduced into four special cases for different values of potential parameters, i.e., hulthn, Manning–Rosen,and Eckart potentials. We also obtain and investigate the scattering amplitudes of these special cases. Some numerical results are also obtained and reported.

关键词： scattering amplitude Schrodinger equation multi-parameter potential phase shifts cross section