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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

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Higher Order Multipole Potentials and Electrostatic Screening Effects on Cohesive Energy and Bulk Modulus of Metallic Nanoparticles

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Communications in theoretical Physics 2011年第12期56卷 1125-1129页

作者： t.Barakat Physics Department King Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia

Higher order rnultipole potentials and electrostatic screening effects are introduced to incorporate the dan gling bonds on the surface of a metallic nanopaticle and to modify the coulornb like potential energy terms, respectively. the total interaction energy function for any rnetallic nanoparticle is represented in terms of two- and three-body potentials. the two-body part is described by dipole-dipole interaction potential, and in the three-body part, triple-dipole （DDD） and dipole-dipole-quadrupole （DDQ） terrns are included. the size-dependent cohesive energy and bulk modulus are observed to decrease with decreasing sizes, a result which is in good agreement with the experimental values of Mo and W nanoparticles.

关键词： higher order multipole potentials electrostatic screening effect size-dependent cohesive energy size-dependent bulk modulus metallic nanoparticles

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Beta-lactam antibiotic resistance among Escherichia coli isolates from patients with urinary tract infections in Vietnam:A systematic review and meta-analysis

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Asian Pacific Journal of tropical Medicine 2024年第6期17卷 243-255,I0001-I0003页

作者： Dat t Nguyen Princess Margaret Cancer Centre University Health NetworkTorontoOntarioCanada

Objective:to investigate the evolving patterns of antimicrobial resistance against beta-lactam antibiotics in Escherichia coli isolates from urinary tract infection patients in Vietnam,covering the period from 2005 to ***:29 Descriptive studies published between 2010 and 2022 in English and Vietnamese were included in the *** on resistance rates to beta-lactam antibiotics,including cephalosporins and carbapenems,were extracted and *** pooled resistance rates were calculated using random-effects *** trends in resistance were assessed using linear regression ***:Among the beta-lactam antibiotics studied,Escherichia coli exhibited varying levels of resistance,with cephalosporins showing higher resistance rates compared to *** pooled resistance rates were 66%for cefotaxime,65%for ceftriaxone,54%for ceftazidime,and 56%for *** contrast,carbapenems demonstrated lower resistance rates,with weighted pooled resistance rates ranging from 3%to 4%for meropenem,ertapenem,and *** rates were also observed for amoxicillin/clavulanate(35%),ticarcillin/clavulanate(26%),and piperacillin/tazobactam(12%).Significant annual increases in resistance were noted for imipenem(0.56%,Pthis study highlights the critical issue of antimicrobial resistance in urinary tract infections in Vietnam and emphasizes the importance of prudent antibiotic use and the regular monitoring of resistance *** insights are useful for guiding healthcare professionals in optimizing treatment strategies and for policymakers in formulating evidence-based clinical guidelines to combat antibiotic resistance effectively.

关键词： Antimicrobial resistance Urinary tract infection Vietnam

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Physics prospects at J-PARC

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Chinese Physics C 2010年第9期34卷 1259-1262页

作者： t.Nagae Kyoto University Department of Physics

We have held an inauguration ceremony of the Japan Proton Accelerator Research Complex （JPARC） on July 6,2009,celebrating the completion of its ***,the beam commissioning of the 50 GeV main proton synchrotron is in progress to improve the beam intensity and quality.A lot of important experimental programs in Nuclear Physics are waiting for the *** this report,I introduce some examples.

关键词： hypernuclei J-PARC hadron kaon

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Recent results from HERA

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Chinese Physics C 2010年第9期34卷 1254-1258页

作者： t.Haas Deutsches Elektronensynchrotron

After the end of data taking in 2007,the experiments H1 and ZEUS have entered into an intense phase of data *** results of this effort on neutral （NC） and charged current （CC） cross sections at high Q 2,the longitudinal structure function F L,inclusive diffraction,heavy flavour production and on searches for glueballs are *** shown are results of a combined analysis on inclusive NC and CC cross sections performed by H1 and ZEUS using HERA-I data.

关键词： lepton-proton scattering structure functions QCD glueballs

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Epigenetic marks in zebrafish sperm： insights into chromatin compaction, maintenance of pluripotency, and the role of the paternal genome after fertilization

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Asian Journal of Andrology 2011年第4期13卷 620-621页

作者： Douglas t Carrell Andrology and IVF Laboratories Departments of Surgery （Urology） Obstetrics and Gynecology and Physiology University of Utah School of Medicine Salt Lake City UT 84108 USA

Human sperm chromatin, and the sperm of most mammals, undergoes extensive remodeling during spermiogenesis during which 85%-95% of the histones are removed and replaced with protamines. the replacement of most histones with protamines facilitates a tighter packaging of the chromatin that is necessary for normal sperm function, and may help protect sperm DNA from damage during transport.

关键词： Biological sciences Evolution Palaeontology

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Pt／Au Schottky Contacts to Modulation—Doped AlxGa1—xN／GaN Heterostructures Using Pre—deposition Surface treatment

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Chinese Physics Letters 2002年第12期19卷 1853-1855页

作者：刘杰 t.Someya 等 NationalLaboratoryofSolidStateMicrostructuresandDepartmentofPhysics NanjingUniversityNanjing210093 ResearchCenterforAdvancedScienceandtechnologyandInstituteofIndustrialScience

Pt/Au Schottky contacts were fabricated on modulation-doped Al0.22GaN0.78/GaN heterostructures. Some different pre-deposition surface treatments were used to prevent the formation of the native oxide layer on the Al0.22GaN0.78 surface. X-ray photoelectron spectroscopy measurements indicate that the pre-deposition surface treatment with boiling (NH4)2S solution can remove the native oxide layer on the Al0.22Ga0.78N surface effectively. the highest Schottky barrier height of 1.13 eV was obtained on the (NH4)2S-treated Al0.22GaN0.78/GaN heterostructure

关键词： Modulation

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Numerical simulation of triaxial compression test for brittle rock sample using a modified constitutive law considering degradation and dilation behavior

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Journal of Central South University 2015年第8期22卷 3097-3107页

作者：谭鑫 KONIEtZKY H FRüHWIRt t College of Civil Engineering Hunan University Geotechnical Institute TU Bergakademie Freiberg

the understanding of the rock deformation and failure process and the development of appropriate constitutive models are the basis for solving problems in rock engineering. In order to investigate progressive failure behavior in brittle rocks, a modified constitutive model was developed which follows the principles of the continuum damage mechanics method. It incorporates non-linear Hoek-Brown failure criterion, confining pressure-dependent strength degradation and volume dilation laws, and is able to represent the nonlinear degradation and dilation behaviors of brittle rocks in the post-failure region. A series of triaxial compression tests were carried out on Eibenstock(Germany) granite samples. Based on a lab data fitting procedure, a consistent parameter set for the modified constitutive model was deduced and implemented into the numerical code FLAC3 D. the good agreement between numerical and laboratory results indicates that the modified constitutive law is well suited to represent the nonlinear mechanical behavior of brittle rock especially in the post-failure region.

关键词： progress failure strength degradation dilation Hoek-Brown criterion numerical simulation brittle rock

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A comparison of genetic risk score with family history for estimating prostate cancer risk

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Asian Journal of Andrology 2016年第4期18卷 515-519页

作者： Brian t Helfand Division of Urology NorthShore University HealthSystem University of Chicago Pritzker School of Medicine 2650 Ridge Avenue Evanston IL 60201 USA.

Prostate cancer （PCa） testing is recommended by most authoritative groups for high-risk men including those with a family history of the disease. However, family history information is often limited by patient knowledge and clinician intake, and thus, many men are incorrectly assigned to different risk groups. Alternate methods to assess PCa risk are required. In this review, we discuss how genetic variants, referred to as PCa-risk single-nucleotide polymorphisms, can be used to calculate a genetic risk score （GRS）. GRS assigns a relatively unique value to all men based on the number of PCa-risk SNPs that an individual carries. this GRS value can provide a more precise estimate of a man＇s PCa risk. this is particularly relevant in situations when an individual is unaware of his family history. In addition, GRS has utility and can provide a more precise estimate of risk even among men with a positive family history. It can even distinguish risk among relatives with the same degree of family relationships. taken together, this review serves to provide support for the clinical utility of GRS as an independent test to provide supplemental information to family history. As such, GRS can serve as a platform to help guide-shared decision-making processes regarding the timing and frequency of PCa testing and biopsies.

关键词： family history genetic risk score prostate cancer single-nucleotide polymorphisms

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Prostate cancer cells metastasize to the hematopoietic stem cell niche in bone

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Asian Journal of Andrology 2011年第4期13卷 622-623页

作者： Evan t Keller Departments of UroJogy and Pathology University of Michigan Ann Arbor MI 48109 USA

the majority of men with advanced prostate cancer develop bone metastases as opposed to metastases at other sites. It has been unclear why prostate cancer selectively metastasizes to and proliferates in bone. Recently, Shiozawa et al. delineated a mechanism that may account for the establishment of prostate cancer in bone. Specifically, they identified that prostate cancer cells compete with hematopoietic stem cells （HSC） for the osteoblast in the HSC niche of the bone. Defining the mechanisms through which prostate cancer cells establish themselves in bone is critical towards developing effective therapeutic strategies to prevent or target bone metastases.

关键词： Biological sciences Cell biology Microbiology

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