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Indian plate paleogeography, subduction and horizontal underthrusting below Tibet: paradoxes, controversies and opportunities

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National Science Review 2022年第8期9卷 175-193页

作者： Douwe j.j.van Hinsbergen Department of Earth Sciences Utrecht University

The India–Asia collision zone is the archetype to calibrate geological responses to continent–continent collision, but hosts a paradox: there is no orogen-wide geological record of oceanic subduction after initial collision around 60–55 Ma, yet thousands of kilometers of post-collisional subduction occurred before the arrival of unsubductable continental lithosphere that currently horizontally underlies Tibet. Kinematically restoring incipient horizontal underthrusting accurately predicts geologically estimated diachronous slab break-off, unlocking the Miocene of Himalaya–Tibet as a natural laboratory for unsubductable lithosphere convergence. Additionally, three endmember paleogeographic scenarios exist with different predictions for the nature of post-collisional subducted lithosphere but each is defended and challenged based on similar data types. This paper attempts at breaking through this impasse by identifying how the three paleogeographic scenarios each challenge paradigms in geodynamics, orogenesis, magmatism or paleogeographic reconstruction and identify opportunities for methodological advances in paleomagnetism, sediment provenance analysis, and seismology to conclusively constrain Greater Indian paleogeography.

关键词： collision orogenesis subduction reconstruction Himalaya Tibet

The moderating effect of physical activity on the relationship between bullying and mental health among sexual and gender minority youth

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journal of Sport and Health Science 2023年第1期12卷 106-115页

作者： Sally j.Kirklewski Ryan j.Watson Carolyn Lauckner Department of Health Promotion and Behavior University of GeorgiaAthensGA 30602USA Human Development and Family Sciences University of ConnecticutStorrsCT 06269 USA Department of Behavioral Science University of Kentucky College of MedicineUniversity of KentuckyLexingtonKY 40506USA

Background:Sexual and gender minority youth frequently experience bullying,which often contributes to higher depressive symptoms and lower self-esteem.Given that physical activity(PA)can mitigate depressive symptoms and improve self-esteem,we examined the moderating effect of PA on the relationship between bullying and mental health among sexual and gender minority youth.Methods:Data from the Lesbian,Gay,Bisexual,Transgender,and Queer National Teen Survey(n=9890)were analyzed.Hierarchical regression analyses examined the influence of history and frequency of being bullied,PA,and the interaction of these variables on depressive symptoms and self-esteem.Simple slopes analyses were used to probe significant interactions.Results:Results indicated the importance of accounting for bullying history when examining effects of PA on mental health.PA was negatively related to depression(t=-4.18,p<0.001)and positively related to self-esteem(t=12.11,p<0.001).Bullying frequency was positively related to depression(t=19.35,p<0.001)and negatively related to self-esteem(t=-12.46,p<0.001).There was a significant interaction between bullying frequency and PA for depression(t=4.45,p<0.001)and self-esteem(t=-4.69,p<0.001).Post hoc analyses suggested that the positive effects of PA on mental health may be limited to those not bullied because it had a negligible effect on those who were bullied.Conclusion:Results suggest that sexual and gender minority youth exercise interventions aiming to improve mental health should first address bullying history;otherwise,their effectiveness may be limited to those who have been bullied.

关键词： Bullying Depression Exercise LGBTQ Self-esteem Youth

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Natural products and drug discovery

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National Science Review 2022年第11期9卷 37-57页

作者： David j.Newman NIH Special Volunteer

This review covers the recent history of a series of very important natural products and their derivatives that are currently in use or under evaluation in the areas of anti-infectives, important cancer treatments that include antibody drug conjugates, followed by a discussion of type 2 diabetes(T2DM) drugs and angiotensin converting enzyme inhibitors. The current structures of the agents are shown, though in the case of some peptides used in T2DM drugs the standard single leTher abbreviation for an amino acid is used.

关键词： artemisinin glycopeptides anthracyclines dolastatin diabetes 2 ACE inhibitors

Geochemical studies of hybrid granite from Madugulapalli area, Eastern Dharwar Craton, Southern India: Implications for crustal mixing

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Acta Geochimica 2023年第1期42卷 9-23页

作者： Nagamma j Ratnakar j Ajay kumar A Ashok Ch State Mines and Geology Department 508001 NalgondaIndia Department of Geology Osmania University500007 HyderabadIndia CSIR-National Geophysical Research Institute 500007 UppalHyderabadIndia

Magma produced by melting of continental crust and mantle at the Archean-Proterozoic boundary are compositionally variable and chemical compositions provide evidence for the mixing of two sources. Understanding the composition of hybrid magma is essential for determining the comparative infl uence of crust and mantle sources during orogenesis. The hybrid granites are less documented in Indian cratons, especially less in Dharwar Craton. Here we present petrographic and whole-rock geochemical data of Madgulapalli granitic rocks situated in the NE part of the Eastern Dharwar Craton(EDC), to elucidate their petrogenesis and role in crust formation. The Madugulapalli granites(MPG) are composed chiefl y of plagioclase, quartz, and alkali feldspar with associated biotite showing alteration and inter-granular textures. Geochemically, they are metaluminous to peraluminous in nature with calc-alkaline hybrid granite. The hybrid granites exhibit both negative and positive europium anomalies;the lower Rb/Sr, Rb, Sr, and higher Sr/Y,(Dy/Yb)N ratios suggest that the interaction of older rocks with residual garnet source melted at high pressures. We hypothesize that hybrid granites are formed by interaction(e.g., metasomatism, mingling, or mixing) between parental magmas and pre-existing rocks with the infl uence of sanukitoid melts(heat source) in a subduction environment. The genesis of the hybrid granites demonstrates the mixing coupled with diff erentiation in the petrogeny’s residue system in a syn-collision setting followed by continental crust stability in EDC during the Neoarchean period.

关键词： Madugulapalli granite Hybrid granite Crustal mixing Subduction

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Effect of surface layer softening from previous electrochemical corrosion on electrochemical cold drawing of Q235 steel bar

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journal of Iron and Steel Research(International) 2022年第5期29卷 819-835页

作者： j.L.Guo T.j.Chen State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou730050GansuChina

The effects of H_(2)SO_(4)concentration and current in electrochemical corrosion on surface layer softening or plasticizing of Q235 steel bar and their effects on subsequent electrochemical cold drawing(ECD)were investigated.The results indicate that the electrochemical corrosion can soften or plasticize the surface layer of Q235 steel bar and then make the subsequent ECD be conducted more easily.The softening degree and thickness of the surface layer are continuously enhanced with increasing corrosion rate,i.e.,increasing H_(2)SO_(4)concentration or current,due to the generation of more vacancy clusters in deeper regions of surface layer.These vacancy clusters then relax dislocations through being absorbed during ECD,and the formation and movement of additional dislocation flux are thereby enhanced,resulting in the further obvious decrease in the drawing force.It is also due to the enhanced formation and movement of additional dislocation flux that the dislocation density and thus the hardness of the surface layer are decreased,as well as that the texture structure is weakened.These behaviors are enhanced as the corrosion rate increases.

关键词： Electrochemical corrosion Electrochemical cold drawing Surface layer softening Vacancy Additional dislocation flux

Two distinct Paleozoic metamorphic events in the Tarim-North China Collage

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National Science Review 2023年第2期10卷 7-8页

作者： jérémie Soldner State Key Laboratory of Isotope Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences CAS Center for Excellence in Deep Earth Science

The Central Asian Or ogenic Belt(CAOB) [1],which includes the Altaids in Central and Northern Asia [2],is the largest accretionary orogen formed during the subduction of the Paleo-Asian Ocean and the Panthalassa Ocean in the period of the Late Proterozoic to Late Paleozoic [3].Closure of the Paleo-Asian Ocean is attributed to the northward drift of the North China and Tarim cratons leading to the massive shortening and oroclinal buckling of the CAOB accretionary system in the Permian [4].

关键词： ASIA SUBDUCTION EVOLUTION SYSTEMS

How to make the "jump" on understanding the importance of the intrinsic foot muscles for propulsion

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journal of Sport and Health Science 2023年第5期12卷 648-650页

作者： Michael j.Asmussen Department of Biology Faculty of Science&TechnologyMount Royal UniversityCalgaryAB T3E 6K6Canada

In this issue of the journal of Sport and Health Science,Smith and colleagues1addressed a unique aspect of human locomotion;they evaluated the effects of the intrinsic foot musculature on the mechanical properties and energetic function of the human foot.By performing a controlled jumping experiment to mimic components of human locomotion.

关键词： intrinsic muscles propulsion

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Storing Freshwater Versus Storing Electricity in Power Systems with High Freshwater Electric Demand

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jOURNAL OF MODERN POWER SYSTEMS AND CLEAN ENERGY 2024年第2期12卷 323-333页

作者： Al-Mubarak, Mubarak j. Conejo, Antonio j. Ohio State Univ Dept Elect & Comp Engn Columbus OH 43210 USA Kuwait Univ Dept Elect Engn POB 5969 Safat 13060 Kuwait Ohio State Univ Dept Integrated Syst Engn Columbus OH 43210 USA

We consider a power system whose electric demand pertaining to freshwater production is high (high freshwater electric demand), as in the Middle East, and investigate the tradeoff of storing freshwater in tanks versus storing electricity in batteries at the day-ahead operation stage. Both storing freshwater and storing electricity increase the actual electric demand at valley hours and decrease it at peak hours, which is generally beneficial in term of cost and reliability. But, to what extent? We analyze this question considering three power systems with different generation-mix configurations, i. e., a thermal-dominated mix, a renewable-dominated one, and a fully renewable one. These generation-mix configurations are inspired by how power systems may evolve in different countries in the Middle East. Renewable production uncertainty is compactly modeled using chance constraints. We draw conclusions on how both storage facilities (freshwater and electricity) complement each other to render an optimal operation of the power system.

关键词： Power system operation freshwater production and transportation coordination day-ahead scheduling COORDINATED OPERATION ENERGY MANAGEMENT UNIT

One-step multi-compositional oxidation of YSi alloy:Experiments and ab initio computation

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journal of Materials Science & Technology 2023年第27期158卷 253-262页

作者： W.j.Wang j.C.Luo L.Chen G.j.Yang State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Xi’an jiaotong University Suzhou Institute Suzhou 215123China

YSi alloy is a promising candidate as oxidation resistant coatings for both the bond coat of environmental barrier coatings(EBCs)and anti-ablation coatings at a high temperature of∼1300℃.In this study,a one-step multi-compositional oxidation by rapid heating oxidation mode is proposed to reduce the oxidation rate by 3.6 times compared to conventional slow heating oxidation mode.Results show that preferentially formed Y_(2)O_(3) oxide initiates a multi-step oxidation,produces a cracking and porous oxides,and thereby resulting in a fast oxidation with pesting.The one-step multi-compositional oxidation with a compact and dense Y_(2)Si_(2)O_(7)scale contributes to the much better oxidation resistance for rapid heating oxidation mode of YSi alloy.The stable formation of Y_(2)Si_(2)O_(7)scale is comprehensively understood by the energy barrier,charge density and electronic level based on density functional theory.This study demonstrates a promising application of YSi alloy by rapid heating oxidation mode.

关键词： YSi alloy One-step oxidation Multi-compositional scale Y_(2)Si_(2)O_(7) Energy barrier