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Precipitation on stacking faults in Mg–9.8wt%Sn alloy

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Journal of Materials Science & Technology 2020年第10期42卷 230-240页

作者： c.Q.Liu c.He H.w.chen J.F.Nie International Joint Laboratory for Light Alloys(Ministry of Education) College of Materials Science and EngineeringChongqing UniversityChongqing400044China Department of Materials Science and Engineering Monash UniversityVictoria3800Australia Electron Microscopy center Chongqing UniversityChongqing400044PR China

In this work,we have systematically investigated precipitation ofβ’-Mg3Sn phase on intrinsic stacking faults I1 and I2 in a Mg-9.8 wt%Sn alloy using aberration-corrected scanning transmission electron *** observed I1 faults are generated by the dissociation of c+a perfect dislocations and bounded by Frank partial dislocations having a Shockley *** ofβ’on I1 involves a shear of 1/3α,similar to its formation directly from theα-Mg ***β’phase often nucleates at one end of an I1 fault due to the interaction between shear strain fields ofβ’and the Shockley component of the Frank partial at that end,and subsequently grows towards the other end of the *** theβ’reaches to the other end,the Shockley partial bounding the lengthening end of theβ’reacts with the Frank partial bounding the fault,generating an a perfect dislocation that can glide away from the precipitate and the *** observed I2 faults are generated by the dissociation of a perfect dislocations and bounded by Shockley *** ofβ’on I2 does not need a shear of 1/3α,since the pre-existing I2 fault already provides an ABcA four-layer structure ofβ’.Thickening of theβ’that has already formed on the I2 involves the successive occurrence of three crystallographically equivalent shears of 1/3αon every second(0002)αplane of theα-Mg *** this thickening mechanism is similar to that of theβ’formed directly from theα-Mg matrix,an a perfect dislocation will be produced when theβ’is thickened to eight layers,and it can again glide away from the precipitate and the fault.

关键词： Heterogeneous precipitation HAADF-STEM Shockley partial dislocation Frank partial dislocation Dislocation reaction

Androgen and bone mass in men

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Asian Journal of Andrology 2003年第2期5卷 148-154页

作者： Annie w.c.Kung Department of Medicine University of Hong Kong Queen Mary Hospital Hong Kong China

Androgens have multiple actions on the skeleton throughout life. Androgens promote skeletal growth and accumulation of minerals during puberty and adolescence and stimulate osteoblast but suppress osteoclast function,... 详细信息

ct>Androgens have multiple actions on the skeleton throughout life. Androgens promote skeletal growth and accumulation of minerals during puberty and adolescence and stimulate osteoblast but suppress osteoclast function, activity and lifespan through complex mechanisms. Also androgens increase periosteal bone apposition, resulting in larger bone size and thicker cortical bone in men. There is convincing evidence to show that aromatization to estrogens was an important pathway for mediating the action of testosterone on bone physiology. Estrogen is probably the dominant sex steroid regulating bone resorption in men, but both testosterone and estrogen are important in maintaining bone formation.

关键词： bone of as et Androgen and bone mass in men in

comments on the release Laboratory Manual for the Human Semen of the 5th edition of the wHO Examination and Processing of

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Asian Journal of Andrology 2010年第1期12卷 59-63页

作者： w. c. L. Ford Obstetrics ＆ Gynaecology Unit Clinical Science at South Bristol University of Bristol St Michael＇s Hospital Bristol BS28EG UK

The authors of the world Health Organization Semen Analysis Manual are to be congratulated on producing a new edition; it is an essential tool to disseminate good practice in andrology. However, the tests described have poor prognostic power to predict a man＇s fertility and show little about the underlying causes of sub-fertility. This commentary urges a revival of research into the diagnosis of male fertility. It suggests that fertility should be regarded as a continuum and that the artificial binary division between fertile and infertile should be abandoned. Models to predict a sub-fertile couple＇s chance of conception in a year should be developed on the basis of prospective data. These models would allow for sophisticated decision making about management. The future lies in the identification of tests to detect underlying pathologies open to specific treatment. Leads such as oxidative stress, defects in the intracellular regulation and the developing field ofproteomics should be explored.

关键词： diagnosis male infertility oxidative stress predictive value of tests sperm count

Ultra‑Transparent and Multifunctional IZVO Mesh Electrodes for Next‑Generation Flexible Optoelectronics

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Nano-Micro Letters 2025年第1期17卷 293-309页

作者： Kiran A.Nirmal Tukaram D.Dongale Atul c.Khot chenjie Yao Nahyun Kim Tae Geun Kim School of Electrical Engineering Korea UniversityAnam‑ro 145Seongbuk‑guSeoulRepublic of Korea computational Electronics and Nanoscience Research Laboratory School of Nanoscience and BiotechnologyShivaji UniversityKolhapur 416004India

Mechanically durable transparent electrodes are essential for achieving long-term stability in flexible optoelectronic ***,they are crucial for applications in the fields of energy,display,healthcare,and soft *** meshes represent a promising alternative to traditional,brittle,metal oxide conductors due to their high electrical conductivity,optical transparency,and enhanced mechanical *** this paper,we present a simple method for fabricating an ultra-transparent conducting metal oxide mesh electrode using selfcracking-assisted *** this method,we produced an electrode with ultra-transparency(97.39%),high conductance(Rs=21.24Ωsq^(−1)),elevated work function(5.16 eV),and good mechanical *** also evaluated the effectiveness of the fabricated electrodes by integrating them into organic photovoltaics,organic light-emitting diodes,and flexible transparent memristor devices for neuromorphic computing,resulting in exceptional device *** addition,the unique porous structure of the vanadium-doped indium zinc oxide mesh electrodes provided excellent flexibility,rendering them a promising option for application in flexible optoelectronics.

关键词： Self-cracking template Vanadium-doped indium zinc oxide mesh Organic solar cells Organic light-emitting diodes Flexible transparent memory

MEcHANIcAL PROPERTIES OF Ti_3Sic_2 AT HIGH TEMPERATURE

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 465-470页

作者： Y.w.Bao Y.c.Zhou Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 ChinaShenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

creep and stress relaxation behavior, the elastic modulus and fracture toughness of machinable Ti3Sic2 at various temperatures from 20 to 1250℃ were investigated by means of three-point bending tests. The experiments were performed respectively at: (i) fixed stress and changed temperatures, and (ii) fixed temperature and changed stresses. A creep resistance parameter that represents the probability of creep deformation in a given condition was defined as a function of both applied stress and the threshold stress, varying in a range from 0 to 1. Elastic modulus at high temperatures was measured through comparing relative slopes of loading curves in cyclic loading curve. The fracture toughness measured by SENB method showed a stable value in the range of 25-1000℃, but over 1000℃, it declined abruptly from -6.7MPa·m1/2 to -2.0MPa·m1/2 at 1200℃.

关键词： high-temperature Ti3Sic2 creep stress relaxation fracture toughness

Improved hemostasis with major hepatic resection in the current surgical era

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Hepatobiliary & Pancreatic Diseases International 2019年第5期18卷 439-445页

作者： christopher w Mangieri Matthew A Strode Bradley c Bandera Department of Surgery Dwight D. Eisenhower Army Medical Center(DDEAMC)Fort GordonGA 30809USA Department of Surgical Oncology Roswell Park Cancer InstituteBuffaloNY 14203USA

Background: Major hepatic resection, predominantly performed for oncologic intent, is a complex procedure with the potential for severe intraoperative hemorrhage. The current surgical era has the ability to improve hemostasis throughout the performance of major hepatic resections which decreases blood transfusions and the detrimental effects associated with transfusion. we evaluated hemostasis and outcomes in the current surgical era of performing hepatic resections. Methods: Utilizing the American college of Surgeons (AcS) National Surgical Quality Improvement Program (NSQIP) database all major hepatic resections performed between 2012 and 2016 were analyzed in regards to hemostasis. Hemostasis was evaluated by the need for and magnitude of blood transfusions. Additional perioperative variables (including operative time, length of hospital stay, and mortality rates) were analyzed to assess for outcomes with hemostasis. The NSQIP results were compared to previous publications involving major hepatic resections to detect improvement in hemostasis and outcomes in the current surgical era. Results: A total of 22777 major hepatic resections met the inclusion criteria for analysis in the NSQIP database. An additional 21198 cases were compiled within the selected publications for comparative analysis. The transfusion rate in the current surgical era was 13.3% versus 38.7% in the previous era ( P = 0.0001). when a transfusion was required in the current surgical era there was a two-fold reduction in the number of units transfused (1.5 U vs. 3.8 U, P = 0.0001). Statistically significant improvements in operative time and length of hospital stay were presented within the current surgical era ( P = 0.0001). when a transfusion was required there was an increased relative risk score of 7 for mortality (4.9% vs. 0.7%, P = 0.0001), however, improvement in mortality rates did not reach statistical significance across surgical eras (1.3% vs. 4.0%, P = 0.0001). conclusions: The cond

关键词： Major hepatic resection Improved hemostasis Improved outcomes

Male courtship signal modality and female mate preference in the wolf spider Schizocosa ocreata: results of digital multimodal playback studies

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current Zoology 2019年第6期65卷 705-711页

作者： Elizabeth c.KOZAK George w.UETZ Department of Biological Sciences University of CincinnatiCincinnatiOHP.0.Box 260006USA45221-0006

Females must be able to perceive and assess male signals,especially when they occur simultaneously with those of other *** studies show female Schizocosa ocreata wolf spiders display receptivity to isolated visual or vibratory courtship signals,but increased receptivity to multimodal *** is unknown whether this is true when females are presented with a choice between simultaneous multimodal and isolated unimodal male *** used digital playback to present females with a choice simulating simultaneous male courtship in different sensory modes without variation in information content:1)isolated unimodal visual versus vibratory signals;2)multimodal versus vibratory signals;and 3)multimodal versus visual *** choosing between isolated unimodal signals(visual or vibratory),there were no significant differences in orientation latency and number of orientations,approaches or receptive displays directed to either *** given a choice between multimodal versus vibratory-only male courtship signals,females were more likely to orient to the multimodal stimulus,and directed significantly more orients,approaches and receptivity behaviors to the multimodal *** presented with a choice between multimodal and visual-only signals,there were significantly more orients and approaches to the multimodal signal,but no significant difference in female *** suggest that signal modes are redundant and equivalent in terms of qualitative responses,but when combined,multimodal signals quantitatively enhance detection and/or *** study confirms the value of testing preference behavior using a choice paradigm,as female preferences may depend on the context(e.g.,environmental context and social context)in which they are presented with male signals.

关键词： mate choice multimodal communication Schizocosa signaling wolf spider

Osteopontin: a leading candidate adhesion molecule for implantation in pigs and sheep

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Journal of Animal Science and Biotechnology 2015年第2期6卷 177-190页

作者： Greg A Johnson Robert c Burghardt Fuller w Bazer Department of Veterinary Integrative Biosciences Texas A&M UniversityCollege Station Department of Animal Science Texas A&M UniversityCollege Station

Osteopontin （OPN; also known as Secreted Phosphoprotein 1, SPP1） is a secreted extra-cellular matrix （EcM） protein that binds to a variety of cell surface integrins to stimulate cell-cell and cell-EcM adhesion and communication. It is generally accepted that OPN interacts with apically expressed integrin receptors on the uterine luminal epithelium （LE） and conceptus trophectoderm to attach the conceptus to the uterus for implantation. Research conducted with pigs and sheep has significantly advanced understanding of the role（s） of OPN during implantation through exploitation of the prolonged peri-implantation period of pregnancy when elongating conceptuses are free within the uterine lumen requiring extensive paracrine signaling between conceptus and endometrium. This is followed by a protracted and incremental attachment cascade of trophectoderm to uterine LE during implantation, and development of a true epitheliochorial or synepitheliochorial placenta exhibited by pigs and sheep, respectively. In pigs, implanting conceptuses secrete estrogens which induce the synthesis and secretion of OPN in adjacent uterine LE. OPN then binds to αvβ6 integrin receptors on trophectoderm, and the αvβ3 integrin receptors on uterine LE to bridge conceptus attachment to uterine LE for implantation. In sheep, implanting conceptuses secrete interferon tau that prolongs the lifespan of cL. Progesterone released by cL then induces OPN synthesis and secretion from the endometrial GE into the uterine lumen where OPN binds integrins expressed on trophectoderm （αvβ3） and uterine LE （identity of specific integrins unknown） to adhere the conceptus to the uterus for implantation. OPN binding to the αvβ3 integrin receptor on ovine trophectoderm cells induces in vitro focal adhesion assembly, a prerequisite for adhesion and migration of trophectoderm, through activation of： 1） P70S6K via crosstalk between FRAP1/MTOR and MAPK pathways; 2） MTOR, PI3K, MAPK3/MAPK1 （Erk1/2） and MAPK14 （p38） signalin

关键词： Implantation Integrins Psteoponti Pigs Sheep

Overview of automotive engine friction and reduction trends-Effects of surface, material, and lubricant-additive technologies

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Friction 2016年第1期4卷 1-28页

作者： Victor w.wONG Simon c.TUNG Massachusetts Institute of Technology Cambridge MA 02139 USA Vanderbilt chemicals LLc Norwalk CT 06856 USA

The increasing global environmental awareness, evidenced by recent worldwide calls for control of climate change and greenhouse emissions, has placed significant new technical mandates for automotives to improve engine efficiency, which is directly related to the production of carbon dioxide, a major greenhouse gas. Reduction of parasitic losses of the vehicle, powertrain and the engine systems is a key component of energy conservation. For engine efficiency improvement, various approaches include improvements in advanced combustion systems, component system design and handling-such as down-sizing, boosting, and electrification-as well as waste heat recovery systems etc. Among these approaches, engine friction reduction is a key and relatively cost-effective approach, which has been receiving significant attention from tribologists and lubricant-lubrication engineers alike. In this paper, the fundamentals of friction specific to the environments of engine components tribology are reviewed, together with discussions on the impact of developing vehicle powertrain technologies, surface and material technologies, as well as lubricant and additive technologies on promises of continuing friction and wear reduction trends. The international accords on climate change require further gains in fuel efficiency and energy sustainability from all industry sectors including those in the automotive and the broader internal combustion engine industries, and the latter encompass off-highway, power generation, marine, and rail industries as well. This paper focsuses on friction reduction in mainly automotive engines, however. The paper starts with a clarification of the common descriptors of mechanical losses and friction in the engine, followed by the topic of lubrication fundamentals such as lubrication regimes. Then the lubrication of the contacting surfaces in each of the major engine subsystems is discussed in turn. These subsystems include the piston assembly: ring-pack/liner,

关键词： powertrain tribology automotive lubricants additive formulation mechanical design surface coatings and textures friction wear