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Effect of refinement of grains and icosahedral phase on hot compressive deformation and processing maps of Mg-Zn-Y magnesium alloys with different volume fractions of icosahedral phase

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journal of Materials Science & technology 2019年第1期35卷 181-191页

作者： t.Y.Kwak W.j.Kim Department of Materials Science and Engineering Hongik University

the effect of the volume fraction of I-phase on the hot compressive behavior and processing maps of the extruded Mg-Zn-Y alloys was examined, and the obtained results were compared with those of the cast alloys in a previous work. the average grain sizes, fractions of dynamically recrystallized(DRXed) grains,and sizes of DRXed grains of the extruded alloys after compressive deformation were significantly smaller,higher and smaller, respectively, than those of the cast alloys after compressive deformation under the same experimental conditions. this was because the microstructures of the extruded alloys, having much more grain boundaries and more refined I-phase particles than the cast alloys, provided a larger number of nucleation sites for dynamic recrystallization than those of the cast alloys. the constitutive equations for high-temperature deformation of the extruded and cast alloys could be derived using the same activation energy for plastic flow, which was close to the activation energy for lattice diffusion in *** with the cast alloys, the onset of the power law breakdown(PLB) occurred at larger ZenerHolloman(Z) parameter values in the extruded alloys. this was because the extruded alloys had finer initial grain sizes and higher fractions of finer DRXed grains compared to the cast alloys, such that the onset of PLB caused by creation of excessive concentrations of deformation-induced vacancies was delayed to a higher strain rate and a lower temperature. the flow-stress difference between the extruded alloys and the cast alloys could be attributed to the difference in the fraction of DRXed grains. According to the processing maps, the extruded alloys exhibited higher power dissipation efficiency and flow stability than the cast alloys. this agreed with the microstructural observations.

关键词： Hot compression Magnesium alloy Processing map Grain refinement Dynamic recrystallization

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Fano-type resonances induced by a boson mode in Andreev conductance

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Chinese Physics B 2015年第1期24卷 449-456页

作者： j.Barański t.Domański Institute of Physics M. Curie-Skodowska University20-031 Lublin Poland

We study spectroscopic signatures of a monochromatic boson mode interacting with a t-shape double quantum dot coupled between the metallic and superconducting leads. Focusing on a weak interdot coupling, we find that the proximity effect together with the bosonic mode are responsible for the series of Fano-type resonances appearing simultaneously at negative and positive energies. We investigate these interferometric features and discuss their influence on the subgap Andreev conductance taking into account the correlation effects driven by the Coulomb repulsion.

关键词： Fano interference Andreev scattering polaronic features

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the hot compressive deformation behavior of cast Mg-Gd-Y-Zn-Zr alloys with and without LPSO phase in their initial microstructures

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journal of Magnesium and Alloys 2022年第10期10卷 2901-2917页

作者： H.t.jeong W.j.Kim Departmentof Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

Samples of Mg-8.2Gd-3.8Y-1.1Zn-0.4Zr alloy with and without an intragranular lamellae-shaped long period stacking ordered(LPSO)phase were prepared through heat treatment and a series of hot compression tests on these materials were conducted to examine and evaluate the influence of LPSO on the hot compressive deformation behavior and deformation mechanisms at a given alloy *** values of activation energy for plastic flow(Qc)of the solution treated(without LPSO phase)and annealed alloys(with intragranular LPSO phase)were larger than that for pure Mg,indicating that the presence of a high amount of rare earth(RE)elements and LPSO in the Mg matrix significantly increases *** Qcvalue of the annealed alloy was larger than that of the solution treated alloy at all the strain levels(223.3 vs.195.5 k j/mol in average)and the largest difference in Qcbetween the two alloys was recorded at the smallest strain of 0.1 where precipitation of LPSO during deformation was limited in the solution treated *** observations imply that the formation of LPSO phase out of the RE-rich solid solution matrix during deformation increases Qc,but the increment is not so *** of the hot compressive data of the alloys with LPSO phase and the alloys with RE-rich solid solution matrix in literatures indicates the similarity of the effect of the LPSO and RE-rich solid solution matrix phases on Qcand high-temperature strength.

关键词： Magnesium alloys LPSO Deformation mechanism Dynamic recrystallization Activation energy for plastic flow Processing maps

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Prograde and retrograde growth of monazite in migmatites:An example from the Nagercoil Block,southern India

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Geoscience Frontiers 2015年第3期6卷 373-387页

作者： tim E.johnson Chris clark Richard j.M.taylor M.Santosh Alan S.Collins Department of Applied Geology The Institute for Geoscience Research(TIGeR)Curtin University School of the Earth Sciences and Resources China University of Geosciences(Beijing) tectonics Resources and Exploration(TRaX)Department of Earth SciencesUniversity of Adelaide

Data from a migmatised metapelite raft enclosed within charnockite provide quantitative constraints on the pressure-temperature-time （P-t-t） evolution of the Nagercoil Block at the southernmost tip of peninsular India. An inferred peak metamorphic assemblage of garnet, K-feldspar, sillimanite, plagioclase, magnetite, ilmenite, spinel and melt is consistent with peak metamorphic pressures of 6-8 kbar and temperatures in excess of 900 ℃. Subsequent growth of cordierite and biotite record high-temperature retrograde decompression to around 5 kbar and 800 ℃. SHRIMP U-Pb dating of magmatic zircon cores suggests that the sedimentary protoliths were in part derived from felsic igneous rocks with Palae- oproterozoic crystallisation ages. New growth of metamorphic zircon on the rims of detrital grains constrains the onset of melt crystallisation, and the minimum age of the metamorphic peak, to around 560 Ma. the data suggest two stages of monazite growth. the first generation of REE-enriched monazite grew during partial melting along the prograde path at around 570 Ma via the incongruent breakdown of apatite. Relatively REE-depleted rims, which have a pronounced negative europium anomaly, grew during melt crystallisation along the retrograde path at around 535 Ma. Our data show the rocks remained at suprasolidus temperatures for at least 35 million years and probably much longer, supporting a long-lived high-grade metamorphic history. the metamorphic conditions, timing and duration of the implied clockwise P-t-t path are similar to that previously established for other regions in peninsular India during the Ediacaran to Cambrian assembly of that part of the Gondwanan supercontinent.

关键词： Monazire Migmatite Zircon Geochronology Phase equilibria modelling Gondwana

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the effects of gonadal hormones on learning and memory in male mammals： A review

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Current Zoology 2011年第4期57卷 543-558页

作者： Stuart t. LEONARD Peter j. WINSAUER Department of Pharmacology and Experimental therapeutics Louisiana State University Health Sciences Center 1901 Perdido Street New Orleans LA 70112-1393

the primary role of the gonadal steroid hormones in mammals is to regulate reproduction and related behaviors; however, both androgens and estrogens are also integrally involved in mediating higher brain function and processes including cognition, neural development, and neural plasticity. In particular, a number of studies show that estradiol modulates dendritic spine growth and synapse density （synaptic plasticity） in the hippocampus of females, and that increased estradiol levels are generally associated with improvements on a variety of learning and memory tasks. While the majority of research has focused on the beneficial effects of estradiol in females, much less attention has been given to testosterone and its effects on learning and memory in males. Similar to estradiol titers in females, testosterone titers in males decline with age, albeit more gradually, and this decline has been correlated with impairment of certain cognitive tasks. Moreover, studies involving both humans and animals indicate that testosterone and its metabolites can augment responding on certain behavioral tasks, depending on the subject＇s current hormonal state, the response required, and the stimuli involved （e.g., those involving spatial or nonspatial stimuli）. While the exact mechanisms by which testosterone exerts its effects on learning and memory are not fully understood, recent findings suggest that testosterone modulates learning and memory in males through an interaction with the cholinergic system. the overall objective of this review is to discuss studies investigating the role of the gonadal hormones in mediating learning and memory processes in male mammals [Current Zoology 57 （4）： 543-558, 2011].

关键词： testosterone Learning and memory Cholinergic system Mammals Cognition Androgens

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Methods for engineering therapeutic peptides

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Chinese Chemical Letters 2018年第7期29卷 1074-1078页

作者： Yaohao Li Kimberly A.clark Zhongping tan Department of Chemistry and Biochemistry and BioFrontiers Institute University of Colorado

Peptides are a class of drugs that have become increasingly important and influential for the treatment of many human diseases. Compared to traditional small molecule drugs, peptides have the potential for higher target specificity and potency, along with better safety profiles. On the other hand, the complex and fragile nature of peptides poses significant challenges for their administration. Of particular concern is that they are often unstable and can be rapidly degraded by various proteases after dosing. to address these inherent problems of peptides, many different methods have been attempted. Here, we briefly review these methods, with an emphasis on the effect of each method.

关键词： therapeutic peptides Engineering Half-life Stability Solubility Aggregation Permeability

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Effect of date palm pollen supplementation on female sexual function in non-menopausal women:A double blind randomized clinical trial

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Chinese Herbal Medicines 2022年第4期14卷 643-648页

作者： Roghayeh Salmani Khadijeh Nasiri Yousef javadzadeh Roya Salmani Cain C.t.clark Vahideh Aghamohammadi Instructor of Midwifery Department of MidwiferyKhalkhal University of Medical SciencesKhalkhal ***Iran Instructor of Nursing Department of NursingKhalkhal University of Medical SciencesKhalkhal ***Iran Biotechnology Research Center and Faculty of Pharmacy Tabriz University of Medical ScienceTabriz ***Iran Department of Midwifery Khalkhal University of Medical SciencesKhalkhal ***Iran Centre for Intelligent Healthcare Coventry UniversityCoventry CV15FB cv13rwUK Nutritional Sciences Department of NutritionKhalkhal University of Medical SciencesKhalkhal ***Iran

Objective:Despite numerous experimental studies in the literature,there are few clinical trials regarding the effect of date palm pollen(DPP)supplementation on sexual function *** the present study,we sought to evaluate the impact of DPP on female sexual function in Iranian non-menopausal ***:Between October 2019 and December 2019,health centers in the city of Khalkhal,volunteers meeting the inclusion criteria were recruited in randomized clinical ***-eight women were randomly stratified and assigned to one of the two study groups:placebo group(n=35)and palm pollen group(n=35),and received a starch or palm pollen capsule(300 mg per day),respectively,for 35 *** Female Sexual Function Index(FSFI)instrument was used to assess female sexual ***:After DPP supplementation,the increase in desire,lubrication,and the overall score,was statistically significant compared to the placebo group(P=0.002,P=0.000,and P=0.042;respectively);Whilst there was no significant differences in the remaining domains(arousal:P=0.763;orgasm:P=0.370;satisfaction:P=0.474;pain:P=0.259).there was a statistically significant positive correlation between the coitus and preintervention levels of desire(r=0.298,P=0.038),arousal(r=0.328,P=0.021),lubrication(r=0.361,P=0.011),orgasm(r=0.320,P=0.025),satisfaction(r=0.327,P=0.022),and overall scores(r=0.338,P=0.018).Conclusion:this study suggests that DPP(300 mg supplementation for 35 d),given to non-menopausal women,could improve the lubrication and desire domains of FSFI.

关键词： date palm polle female lubrication randomized controlled trial sexual dysfunction

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AGWO-CNN Classification for Computer-Assisted Diagnosis of Brain tumors

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Computers, Materials & Continua 2022年第4期71卷 171-182页

作者： t.jeslin j.Arul Linsely Department of Electronics and Communication Engineering Universal College of Engineering and TechnologyVallioor627117India Department of Electrical and Electronics Engineering Noorul Islam Centre for Higher EducationKumarakovil629180India

Brain cancer is the premier reason for cancer deaths all over the *** diagnosis of brain cancer at an initial stage is mediocre,as the radiologist is *** experiments have been conducted and demonstrated clearly that the algorithms for nodule segmentation are ***,the research has consolidated incremental clustering focused on superpixel segmentation as an appropriate optimization approach for the accurate segmentation of pulmonary *** key aim of the research is to refine brain Ct images to accurately distinguish tumors and the segmentation of small-scale anomalous nodules in the brain *** the beginning stage,an anisotropic diffusion filters(ADF)method with un-sharp intensification masking is utilized to eliminate the noise discernment in *** the following stage,within the improved nodule image sequence,a Superpixel Segmentation Based Iterative Clustering(SSBIC)algorithm is proposed for irregular brain tissue ***,the brain nodule samples are captured using deep learning methods:Advanced Grey Wolf Optimization(AGWO)with ONN(AGWO-ONN)and Advanced GWO with CNN-based(AGWOCNN).the proposed technique indicates that the sensitivity is increased and the calculation time is ***,the proposed methodology manifests that the advanced Computer-Assisted Diagnosis(CAD)system has outstanding potential for automatic brain tumor *** average segmentation time of the nodule slice order is 1.06s,and 97%of AGWO-ONN and 97.6%of AGWO-CNN achieve the best classification reliability.

关键词： Advanced GWO with ONN(AGWO-ONN) Advanced GWO with CNN(AGWO-CNN) brain cancer superpixel segmentation based iterative clustering(SSBIC)algorithm

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trace element characteristics of partial melts produced by melting of metabasalts at high pressures: Constraints on the formation condition of adakitic melts

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Science China Earth Sciences 2006年第9期49卷 915-925页

作者： j. Adam t.H. Green GEMOC National Key Centre Department of Earth and Planetary Sciences Macquarie University Sydney NSW 2109 Australia GEMOC National Key Centre Department of Earth and Planetary Sciences Macquarie University Sydney NSW 2109 Australia

Experiments were conducted on a natural basalt (with 5 wt.% added H2O) at 1.0―2.5 GPa and 900―1100℃. Experimental products include partial melts (quenched glasses) + residual mineral assemblages of amphibolite or eclogite. Electron microprobe and LAM-ICP-MS were used to determine major and trace element compositions of these quenched melts, respectively. Major ele- ment compositions of all the melts are tonalitic- trondhjemitic, similar to adakite. their trace element characteristics are controlled by coexisting residual minerals. Signatures of adakite such as high Sr/Y, low HREE and negative Nb-ta anomaly, etc. are present only in the melts coexisting with residual assemblages containing rutile and garnet (rutile-bearing eclogite or rutile-bearing amphibole-eclogite). Garnet leads to HREE depletion in melts, whereas rutile controls Nb and ta partitioning during the partial melting and causes negative Nb-ta anomaly in melts. therefore, in addition to garnet, rutile is also a necessary residual phase during the generation of adakite or ttG magmas to account for the negative Nb-ta anomaly of the magmas. the depth for the generation of adakite/ttG magmas via melting of metabasalt must be more than about 50 km based on the approximate 1.5 GPa mini- mum-pressure for rutile stability in the partial melting field of hydrous basalt.

关键词： trace element adakite/ttG magmas partial melting of metabasalt negativeNb-ta anomaly rutile

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tsallis holographic dark energy under complex form of quintessence model

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Communications in theoretical Physics 2023年第2期75卷 157-167页

作者： j Sadeghi S Noori Gashti t Azizi Department of Physics Faculty of Basic SciencesUniversity of Mazandaran P.O.Box 47416-95447BabolsarIran

In this paper,we use a tsallis holographic dark energy model in two forms,interacting and noninteracting cases,to acquire some parameters as the equation of state for the energy density of the tsallis model in the FRW Universe concerning the complex form of quintessence *** will study the cosmology of complex quintessence by revamping the potential and investigating the scalar field *** we analyze(w-w’)and stability in two cases,*** and *** will explore whether these cases describe a real Universe by calculating fractional energy densityΩ_(D)and concerning two parts of the quintessence field effect(complex and real part)by considering the real part of this field to be a slow-roll *** know that the part in which the fractional energy density(Ω_(D)>1)does not describe a real ***,we specified an interacting coupling parameter b2that depends on the constant parameter of the tsallis holographic model(δ)with respect to fractional energy density(0.73).Unlike independence between the fractional energy density and interacting coupling in the real quintessence model,we determine a relationship among these parameters in this ***,by plotting some figures,we specify the features of(w-w’)and(ν^(2)_(s))in two cases and compare the result with each other.

关键词： tsallis holographic model complex form of quintessence model stability

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