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gamma Irradiation effects in InBi_(0.8) Te_(0.2) crystals grown by Horizontal Directional Freezing

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Acta Metallurgica Sinica(english Letters) 2015年第10期28卷 1205-1213页

作者： c.J.Ajayakumar A.g.Kunjomana Department of Physics Crystal Research CentreChrist University

The high-energy gamma-ray irradiation treatment using co-60 isotope offers the possibility of engineering mechanical and optoelectronic properties of In Bi0.8Te0.2crystals. Tellurium-doped indium bismuthide（In Bi） crystals were prepared by horizontal directional freezing technique. Dose-dependent modifications in structure, composition and surface topographical features have been analyzed by X-ray powder diffraction, X-ray energy-dispersive analysis, transmission electron and atomic force microscopy, respectively. Dielectric constant and dielectric loss were found to increase with the cumulative dose of radiation, and a shift in the ferroelectric transition temperature（Tc） from 405 to 410 K was observed for25 k gy. Upon irradiation, there is an enhancement in microhardness（HV）, yield stress（ry） and stiffness constant（c11）.The optical transmittance was decreased by 12.45%, resulting in a reduction in the optical band gap from 0.210 e V to0.198 e V. These results indicate the suitability of In Bi0.8Sb0.2crystals for low-wavelength infrared applications.

关键词： crystal growth Dielectric properties Optical properties Hardness Irradiation

Influence of Te doping on the dielectric and optical properties of InBi crystals grown by directional freezing

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International Journal of Minerals,Metallurgy and Materials 2014年第5期21卷 503-509页

作者： c.J. Ajayakumar A.g. Kunjomana crystal Research centre Department of PhysicsChrist University

Stoichiometric pure and tellurium （Te） doped indium bismuthide （InBi） were grown using the directional freezing technique in a fabricated furnace. The X-ray diffraction profiles identified the crystallinity and phase composition. The surface topographical features were observed by scanning electron microscopy and atomic force microscopy. The energy dispersive analysis by X-rays was performed to identify the atomic proportion of elements. Studies on the temperature dependence of dielectric constant （e）, loss tangent （tan6）, and Ac conductivity （cry） reveal the existence of a ferroelectric phase transition in the doped material at 403 K. When InBi is doped with tellurium （4.04 at%）, a band gap of 0.20 eV can be achieved, and this is confirmed using Fourier transform infrared studies. The results thus show the conversion of semimetallic InBi to a semiconductor with the optical properties suitable for use in infrared detectors.

关键词： crystals indium bismuthide tellurium doping optical properties dielectric properties phase transitions

Purinergic contraction of the rat vas deferens in L-NAMe-induced hypertension：effect of sildenafil

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Asian Journal of Andrology 2010年第3期12卷 415-421,I0012页

作者： Serap gur Suresh c. Sikka gillian e. Knight geoffrey Bumstock Wayne J.g. Hellstrom Department of Urology Tulane University Health Sciences Center New Orleans LA 70112 USA Autonomic Neuroscience centre Royal Free and University College Medical School Rowland Hill Street London NW32PF UK

Hypertension （HTN） is a risk factor for erectile dysfunction, but its effect on vas deferens （VD） contractility and the ejaculatory response has not been delineated. Ng-nitro-L-arginine methyl ester （L-NAMe）, a nitric oxide synthase inhibitor, was used for induction of nitric oxide （NO）-deficient HTN. Our aim was to evaluate the effects of L-NAMe-induced HTN on rat VD contractility and to determine whether sildenafil affects VD contractility. A total of 36 male rats were divided into （1） control, （2）L-NAMe-HTN, （3） sildenafil treated L-NAMe-HTN groups. group 2 was treated with L-NAMe （40 mg kgI per day） in drinking water for 4 weeks. group 3 received sildenafil （1.5 mg kg^-1 per day, by oral gavage） concomitantly with L-NAMe. The prostatic portion of the VD was subjected to electrical field stimulation （eFS, 1-20 Hz）, and the P2X1 agonist α,β-methylene ATP （α,β meATP, 100 μmol L^-1-1 μmol L-1） and the al-adrenoceptor agonist phenylephrine （Phe, 100 μmol L^-1-1 mmol L^-1） were used to construct concentration-response curves. These experiments were repeated in the presence of P2X receptor antagonist, pyridoxalphosphate-6-azophenyl-2＇,4＇-disulfonic acid （PPADS, 30 μmol L-1）. VD contractions in response to eFS, a,β-meATP and Phe were significantly enhanced by L-NAMe. Sildenafil treatment in the L-NAMe group improved the contractile response of VD to eFS （20 Hz）. In the presence of PPADS, the enhanced contractile response of VD to eFS and a,β-meATP in hypertensive rats was reversed. In the rat model of chronic NO depletion, the purinergic and adrenergic components and eFS affect VD contractility. The VD contractile response may be mediated more by the purinergic system than the adrenergic system, and sildenafil may alter the ejaculatory response in men with Pe.

关键词： hypertensive rat Ng-nitro-L-arginine methyl ester purinergic receptors P2X sildenafil vas deferens

Functional roles and clinical values of insulin-like growth factor-binding protein-5 in different types of cancers

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chinese Journal of cancer 2012年第6期31卷 266-280页

作者： gökçe güllü Sevgi Karabulut Mustafa Akkiprik Department of Medical Biology School of MedicineDMarmara University

Insulin-like growth factor-bindin g proteins (IgFBPs) are critical regulators of the mitogenic activity of insulin-like growth factors (IgFs). IgFBP5, one of these IgFBPs, has special structural features, including a nuclear transport domain, heparin-binding motif, and IgF/extracellular matrix/acid-labile subunit-binding sites. Furthermore, IgFBP5 has several functional effects on carcinogenesis and even normal cell processes, such as cell growth, death, motility, and tissue remodeling. These biological effects are sometimes related with IgF (IgF-dependent effects) and sometimes not (IgF-independent effects). The functional role of IgFBP5 is most likely determined in a cell-type and tissue-type specific manner but also depends on cell context, especially in terms of the diversity of interacting proteins and the potential for nuclear localization. clinical findings show that IgFBP5 has the potential to be a useful clinical biomarker for predicting response to therapy and clinical outcome of cancer patients. In this review, we summarize the functional diversity and clinical importance of IgFBP5 in different types of cancers.

关键词：胰岛素样生长因子结合蛋白临床价值组织类型癌症患者细胞外基质 IgFs 生物标志物有丝分裂

Present status and future directions:Apexification

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World Journal of Methodology 2025年第1期15卷 26-32页

作者： Sachin chauhan Radha chauhan Prashant Bhasin Bhavna g Sharaf Department of conservative Dentistry and endodontics Sudha Rustagi College of Dental Sciences and ResearchFaridabad 121002HaryanaIndia Department of Prosthodontics and crown and Bridge and Oral Implantology Mahatma Gandhi Dental College&HospitalJaipur 302022RajasthanIndia Department of Pedodontics and Preventive Dentistry Sudha Rustagi College of Dental Sciences and ResearchFaridabad 121002HaryanaIndia

The success rate of apexification is primarily determined by multiple factors,including the material used,the size of the open apex compared to the length of the root,and the technique used in each *** main objective of this review was to provide an update on the present management of open apex to identify factors and circumstances that may influence the success of apexification using different materials and *** research on apexification should focus on how to treat open apices with wide periapical lesions without ***,the predictability of these parameters with non-surgical procedures was uncertain,but now,with the use of a dental operating microscope,it has become more *** reason could be that extra visits are no longer required due to major advances in the armamentarium and materials used for apexification.

关键词： Bioceramics Magnification Biodentine Mineral trioxide aggregate Apexification Open apex

Simultaneous extraction of Phosphorus, Potassium, calcium and Magnesium from Soils and Potassium Recommendations for crops in Southern Brazil

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Pedosphere 2011年第3期21卷 365-372页

作者： L.BORTOLON c.gIANeLLO S.WeLTeR R.g.O.ALMeIDA e.gIASSON Department of Soil Science Federal University of Rio Grande do SulPorto AlegreRS (Brazil)

Simultaneous multi-element extraction has been increasing worldwide to improve soil laboratory testing quality and efficiency. This study sought to investigate the applicability of the Mehlich-1, Mehlich-3, and resin methods for simultaneous extraction of soil available P, K, ca, and Mg as well as the effect of using conversion equations on nutrient recommendations for crops. Topsoil （0-20 cm） samples were taken from the most representative soil types used for crop production in southern Brazil with a wide range of chemical, physical, and mineralogical properties. Soil P, K, ca, and Mg were simultaneously extracted using 1.0 mol L-1 Kcl, Mehlich-1 and Mehlich-3 solutions, and membrane resin. The amounts of P extracted with the Mehlich-1 method were, on average, 50% lower than those extracted with the resin and Mehlich-3 methods. However, the resin method extracted the lowest amounts of K, ca, and Mg. The use of conversion equations was suitable and it did not affect negatively the K recommendations for crops grown on soils of southern Brazil.

关键词： Mehlich-1 Mehlcih-3 membrane resin multi-element extraction soil testing

A functional tacrolimus-releasing nerve wrap for enhancing nerve regeneration following surgical nerve repair

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Neural Regeneration Research 2025年第1期20卷 291-304页

作者： Simeon c.Daeschler Katelyn J.W.So Konstantin Feinberg Marina Manoraj Jenny cheung Jennifer Zhang Kaveh Mirmoeini JPaul Santerre Tessa gordon gregory HBorschel SickKids Research Institute Neuroscience and Mental Health ProgramTorontoONCanada Institute of Biomaterials and Biomedical engineering University of TorontoTorontoONCanada Indiana University School of Medicine IndianapolisINUSA Division of Plastic and Reconstructive Surgery the Hospital for Sick ChildrenTorontoONCanada Translational Biology and engineering Program Ted Rogers Centre for Heart ResearchInstitute of Biomedical EngineeringFaculty of DentistryUniversity of TorontoTorontoONCanada

Axonal regeneration following surgical nerve repair is slow and often incomplete,resulting in poor functional recovery which sometimes contributes to lifelong ***,there are no FDA-approved therapies available to promote nerve *** accelerates axonal regeneration,but systemic side effects presently outweigh its potential benefits for peripheral nerve *** authors describe herein a biodegradable polyurethane-based drug delivery system for the sustained local release of tacrolimus at the nerve repair site,with suitable properties for scalable production and clinical application,aiming to promote nerve regeneration and functional recovery with minimal systemic drug *** is encapsulated into co-axially electrospun polycarbonate-urethane nanofibers to generate an implantable nerve wrap that releases therapeutic doses of bioactive tacrolimus over 31 *** and drug loading are adjustable for applications in small and large caliber nerves,and the wrap degrades within 120 days into biocompatible *** released from the nerve wrap promotes axon elongation in vitro and accelerates nerve regeneration and functional recovery in preclinical nerve repair models while off-target systemic drug exposure is reduced by 80%compared with systemic *** its surgical suitability and preclinical efficacy and safety,this system may provide a readily translatable approach to support axonal regeneration and recovery in patients undergoing nerve surgery.

关键词： biodegradable local drug delivery nerve injury nerve regeneration nerve wrap tacrolimus

effect of particle Froude number on sub-grid effective drag,filtered and residual stresses in fluidized gas-particle flows

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Particuology 2024年第12期95卷 36-48页

作者： christian c.Milioli Fernando e.Milioli Department of Mechanical engineering School of Engineering of São CarlosUniversity of São Paulo13566-590São CarlosSPBrazil

Sub-grid effective drag,filtered and residual stresses in the meso-scale of gas-particle fluidized flows are intrinsically affected by underlying micro-scale conditions as well as non-local effects related to macro-scale *** this work we applied microscopic two-fluid modeling to experiment with particle Froude number in order to evaluate the impact of this micro-scale condition over the concerning meso-scale derived sub-grid *** performed highly resolved simulations in periodic domains for particle Froude numbers from 12.21 to 799.22,for a wide range of macro-scale *** were filtered and classified by ranges of meso-scale markers for the various particle Froude *** particle Froude number was found to considerably affect the structural refinement of the heterogeneous flow fields thereby directly impacting effective drag,filtered and residual *** of those parameters showed systematic behaviors in relation to particle Froude number,thereby providing sound data for new sub-grid modeling propositions.

关键词： Fluidization gas-particle flows Two-fluid model Sub-grid analysis Multiscale analysis

Free vibration and transient response of double curved beams connected by intermediate straight beams

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Applied Mathematics and Mechanics(english edition) 2025年第1期46卷 37-62页

作者： R.A.JAFARI-TALOOKOLAeI H.gHANDVAR e.JUMAeV S.KHATIR T.cUONg-Le School of Mechanical engineering Babol Noshirvani University of Technology Department of Mechanical engineering Faculty of Engineering New Uzbekistan University University of Business and Science center for engineering Application and Technology Solutions Ho Chi Minh City Open University

This paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FgP) materials. The strain potential and kinetic energies of each beam along with the work done by the external force are calculated. Additionally, a higher-order beam element is introduced to derive stiffness and mass matrices, along with the force vector. The curved and straight beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. Subsequently, the natural frequencies and transient response of the system are determined. The accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANSYS, demonstrating excellent ***, a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

关键词： Kinetic energy