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Human enamel thickness and ENAM polymorphism

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International Journal of Oral Science 2016年第2期8卷 93-97页

作者： Diane M Daubert Joanna L kelley Yuriy G Udod Carolina Habor Chris G kleist Ilona k Furman Igor N Tikonov Willie J Swanson frank A Roberts Department of Periodontics University of Washington Center for Reproductive Biology and School of Biological Sciences Washington State University Department of Oral and Maxillofacial Surgery University of Texas Southwestern Medical Center Department of Genome Sciences University of Washington

The tooth enamel development gene, enamelin （ENAM）, showed evidence of positive selection during a genome-wide scan of human and primate DNA for signs of adaptive evolution. The current study examined the hypothesis that a single-nucleotide polymorphism （SNP） C14625T （rs7671281） in the ENAM gene identified in the genome-wide scan is associated with a change in enamel phenotype. African Americans were selected as the target population, as they have been reported to have a target SNP frequency of approximately 50%, whereas non-Africans are predicted to have a 96% SNP frequency. Digital radiographs and DNA samples from 244 teeth in 133 subjects were analysed, and enamel thickness was assessed in relation to SNP status, controlling for age, sex, tooth number and crown length. Crown length was found to increase with molar number, and females were found to have thicker enamel. Teeth with larger crowns also had thicker enamel, and older subjects had thinner enamel. Linear regression and generalized estimating equations were used to investigate the relationship between enamel thickness of the mandibular molars and ENAM SNP status; enamel in subjects with the derived allele was significantly thinner （P= 0.040） when the results were controlled for sex, age, tooth number and crown length. The derived allele demonstrated a recessive effect on the phenotype. The data indicate that thinner dental enamel is associated with the derived ENAM genotype. This is the first direct evidence of a dental gene implicated in human adaptive evolution as having a phenotypic effect on an oral structure.

关键词： enamel genetics polymorphisms tooth development

No relationship between biopsy sites near the main testicular vessels or rete testis and successful sperm retrieval using conventional or microdissection biopsies in 220 non-obstructive azoospermic men

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Asian Journal of Andrology 2013年第6期15卷 795-798,I0009页

作者： J Ullrich Schwarzer Heiko Steinfatt Heiko Steinfatt Manfred Schleyer frank M kōhn klaus Fiedler2, Irene von Hertwig Gottfried krüsmann Wolfgang Würfel Andrologie Centrum MOnchen MOnchen D-81241 Germany kinderwunsch Centrum MOnchen MOnchen D-81241 Germany Andrologicum MOnchen MOnchen D-80331 Germany

In 220 consecutive patients with non-obstructive azoospermia, sperm retrieval was attempted by a combination of conventional and microdissection testicular sperm extraction （TESE）. For sperm retrieval, 2-3 conventional biopsies were performed followed by a microdissection TESE in cases of negative conventional biopsies. During the surgery, the vasculature of the testis was assessed using the operative microscope, and the location of positive biopsies was registered in relation to the blood supply. The overall sperm retrieval rate was 58.2%. From the initial conventional biopsies, sperm could be retrieved in 46.8% of the patients. With microdissection TESE, sperm could be retrieved from an additional 11.4% of the patients. The further use of microdissection TESE improved the sperm retrieval rate significantly （P=0.017）. No significant accumulation of positive biopsies was found towards the rete testis or the main testicular vessels.

关键词： intracytoplasmic sperm injection male infertility microdissection testicular sperm extraction non-obstructiveazoospermia sperm retrieval

Does laser surface texturing really have a negative impact on the fatigue lifetime of mechanical components?

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Friction 2021年第6期9卷 1766-1775页

作者： Chia-Jui HSU Andreas STRATMANN Simon MEDINA Georg JACOBS frank MÜCkLICH Carsten GACHOT Institute for Engineering Design and Product Development TU WienLehárgasse 6Campus GetreidemarktVienna 1060Austria Chair of Functional Materials Saarland UniversityCampus D3.3Saarbrücken 66123Germany AC2T Research GmbH Viktor-Kaplan-Straße 2/CWiener Neustadt 2700Austria Institute for Machine Elements and Systems Engineering RWTH AachenSchinkelstraße 10Aachen 52062Germany

Laser surface texturing(LST)has been proven to improve the tribological performance of machine *** micro-scale patterns manufactured by LST may act as lubricant reservoirs,thus supplying oil when encountering insufficient ***,not many studies have investigated the use of LST in the boundary lubrication regime,likely due to concerns of higher contact stresses that can occur with the increasing surface *** study aims to examine the influence of LST on the fatigue lifetime of thrust rolling bearings under boundary lubrication.A series of periodic patterns were produced on the thrust rolling bearings,using two geometrically different designs,namely cross and dimple *** oil ISO VG 100 mixed with 0.05 wt%P of zinc dialkyldithiophosphate(ZDDP)was *** bearings with cross patterns reduce the wear loss by two orders of *** patterns not only retain lubricant in the textured pockets but also enhance the formation of an anti-wear *** tribofilm generation may be improved by the higher contact stresses that occur when using the textured ***,in contrast to the negative concerns,the ball bearings with cross patterns were instead found to increase the fatigue life by a factor of three.

关键词： thrust rolling bearing laser surface texturing direct laser interference patterning zinc dialkyldithiophosphate(ZDDP) tribofilm

Influence of the changing environment on food composition and condition factor in Labeo victorianus(Boulenger,1901)in rivers of Lake Victoria Basin,kenya

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Aquaculture and Fisheries 2023年第2期8卷 227-238页

作者： Nelly F.Nakangu frank O.Masese James E.Barasa Geraldine k.Matoll Jacques W.Riziki Mulongaibalu Mbalassa Department of Fisheries&Aquatic Sciences University of EldoretEldoretPO Box 1125-30100Kenya Unit´e d’Enseignement et de Recherche en Hydrobiologie Appliqu´ee(UERHA) D´epartement de Biologie-ChimieInstitut Sup´erieur P´edagogique de Bukavu(ISP)RDB.P.854 BukavuCongo School of Life Sciences College of AgricultureEngineering and ScienceUniversity of KwaZulu-NatalScottsvillePietermaritzburg320012South Africa

Labeo victorianus(Boulenger,1901)is one of the endemic fishes in Lake Victoria Basin(LVB)but is now threatened by multiple stressors caused by human *** investigated spatial and temporal variability in food composition and condition of *** in influent rivers of Lake Victoria,*** was done during the dry and wet seasons by *** composition analysis showed that *** is a benthophagus and omnivorous species whose diet is dominated by detritus,periphyton and *** were differences in food composition among rivers,with significant river X season interactions(PERMANOVA F=11.6,df=4,p=0.001),suggesting that the diet depended on prevailing environmental *** turbid rivers,the diet was dominated by detritus while in less turbid rivers it was dominated by insects and *** and mud also formed a significant part of the diet,which was an indication of a limited occurrence of preferable food *** were ontogenetic shifts in food composition(PERMANOVA F=4.6,df=3,p=0.001),but also with a spatial interaction(PERMANOVA F=5.6,df=7,p=0.001),further indicating the role of environmental conditions in determining the diet for different size ***,the fish condition did not differ among *** study shows that turbidity and organic matter and nutrient loading determine the diet of *** in LVB rivers,and provides further justification for the maintenance of water quality as a conservation measure for threatened species.

关键词： Condition factor Feeding Labeo victorianus Ontogenetic shifts Seasonality Tropics

柴达木盆地北缘大柴旦地区古生代花岗岩锆石SHRIMP定年

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岩石学报 2007年第8期23卷 1861-1875页

作者：吴才来郜源红吴锁平陈其龙 Joseph L.WOODEN frank k.MAZADAB Chris MATTINSON 中国地质科学院地质研究所火成岩研究室北京100037 美国斯坦福大学斯坦福加里佛尼亚94305

大柴旦地区是柴北缘古生代超高压带的重要组成部分,与超高压岩石相伴的花岗岩十分发育。这些花岗岩具有两类不同的岩石地球化学特征,Ⅰ类以 Na_2O/k_2O 比值小于1、明显的负 Eu 异常和低 Sr、高 Y 为特征,具有 S-型花岗岩的属性,Ⅱ类以 ... 详细信息

大柴旦地区是柴北缘古生代超高压带的重要组成部分,与超高压岩石相伴的花岗岩十分发育。这些花岗岩具有两类不同的岩石地球化学特征,Ⅰ类以 Na_2O/k_2O 比值小于1、明显的负 Eu 异常和低 Sr、高 Y 为特征,具有 S-型花岗岩的属性,Ⅱ类以 Na_2O/k_2O 比值大于1、弱负 Eu 异常到正 Eu 异常和高 Sr、低 Y 为特征,具有Ⅰ-型花岗岩的属性,反映了它们的源岩及成因上的差异。锆石 SHRIMP U—Ph 定年结果表明,大柴旦地区花岗岩的年龄可分为三组,第一组年龄为446.3±3.9Ma,第二组年龄分别为408.6±4.4Ma、403.3±3.8Ma、401.8±3Ma,第三组年龄分别为374.5±1.6Ma、372±2.1Ma。结合区域地质特征,我们认为,第一组年龄可能反映了柴达木陆块与中南祁连板块碰撞的时代,第二组年龄可能反映了深俯冲地下的板块由于拆沉而折返的时代,第三组年龄可能反映了碰撞隆起后造山带上不同块体之间的伸展、滑塌的时代。

关键词：花岗岩锆石SHRIMP U-Pb定年大柴旦柴北缘

Stand structure and productivity of Populus euphratica along a gradient of groundwater distances at the tarim River(NW china)

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Journal of Plant Ecology 2017年第5期10卷 753-764页

作者： frank M.Thomas Michael Jeschke Ximing Zhang Petra Lang Geobotany Faculty of Regional and Environmental SciencesUniversity of TrierBehringstraße 2154296 TrierGermany Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences40 South Beijing Road830011 UrumqiChina

Aims Along central-Asian rivers in arid regions,lowering of the ground-water level constitutes a major threat to the riparian forests,whose tree layers are dominated by Euphrates poplar(Populus euphratica).Some of these fragile ecosystems are supplied with additional(‘eco-logical’)water for protection and *** investigated interrelationships among groundwater distance,stand structure and above-ground wood production(at the tree and the stand level)in *** stands along a groundwater gradient(distances of 2.0-12.0 m)that also included a plot supplied with‘ecological water’.Methods We measured the height,diameter at breast height and basal area of poplar trees and determined the annual above-ground wood production for the three most recent years on the basis of tree-ring analyses and allometric regressions at three sites at the upper,mid-dle and lower reaches of the tarim River,Xinjiang,NW *** Findingsthe distribution of age classes differed significantly among the plots:in accordance with their life histories,stands growing at a larger distance to the groundwater harboured a larger fraction of old trees(>80 years)and,in most cases,a smaller fraction of young trees(≤20 years).the annual above-ground wood production per ha was highest on a plot with a short groundwater distance(2.0 m;maxi-mum of the 3-year investigation period:3.0 t ha−1 a−1)and lowest,at a plot with a large distance to the water table(6.6 m;minimum:0.23 t ha^(−1)a^(−1)).However,the plot located close to the groundwater(and to the river)at the middle reaches exhibited a relatively large interannual variation in above-ground wood production,which can be attributed to interannual variations in the river *** the middle and the lower reaches,these interannual variations on plots with the most favourable water supply were even more obvious at the tree *** the fraction of mature trees(60-99 years old),no significant differences in above-ground wood production were

关键词： allometry ground water life history tree-age distribution tugai forest

Sampled-data control through model-free reinforcement learning with effective experience replay

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Journal of Automation and Intelligence 2023年第1期2卷 20-30页

作者： Bo Xiao H.k.Lam Xiaojie Su Ziwei Wang frank P.-W.Lo Shihong Chen Eric Yeatman Department of Electrical and Electronic Engineering Imperial College LondonLondon SW72AZUK Department of Engineering King’s College LondonLondon WC2B 4BGUK Department of Automation Chongqing UniversityShapingba DistrictChong QingChina School of Engineering Lancaster UniversityLA14YWUK Hamlyn Centre Imperial College LondonLondon SW72AZUK

Reinforcement Learning(RL)based control algorithms can learn the control strategies for nonlinear and uncertain environment during interacting with *** by the rewards generated by environment,a RL agent can learn the control strategy directly in a model-free way instead of investigating the dynamic model of the *** the paper,we propose the sampled-data RL control strategy to reduce the computational *** the sampled-data control strategy,the whole control system is of a hybrid structure,in which the plant is of continuous structure while the controller(RL agent)adopts a discrete *** that the continuous states of the plant will be the input of the agent,the state–action value function is approximated by the fully connected feed-forward neural networks(FCFFNN).Instead of learning the controller at every step during the interaction with the environment,the learning and acting stages are decoupled to learn the control strategy more effectively through experience *** the acting stage,the most effective experience obtained during the interaction with the environment will be stored and during the learning stage,the stored experience will be replayed to customized times,which helps enhance the experience replay *** effectiveness of proposed approach will be verified by simulation examples.

关键词： Reinforcement learning Neural networks Sampled-data control Model-free Effective experience replay

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六步法三维编织C型预制件实践

上海纺织科技 2020年第12期48卷 57-60页

作者：陈和春 frank.k.ko 江苏工程职业技术学院纺织服装学院江苏南通226007 英属哥伦比亚大学材料工程学院加拿大

四步法三维编织技术可以获得矩形截面的三维编织材料。将矩形编织区域划分成若千个小的并相连的编织区域,通过六步编织,在每一个小的编织区内都完成一个完整的四步法编织。携纱器穿行在相互连接的矩形编织区之间,将若干矩形编织区域连... 详细信息

四步法三维编织技术可以获得矩形截面的三维编织材料。将矩形编织区域划分成若千个小的并相连的编织区域,通过六步编织,在每一个小的编织区内都完成一个完整的四步法编织。携纱器穿行在相互连接的矩形编织区之间,将若干矩形编织区域连接在一起形成一个整体。六步法编织C型预制件中编织区域划分为3个小的编织区,编织过程中携纱器在3个相连的编织区中穿行,最终编织成-个C型截面的预制件。

关键词：三维编织六步法 C型预制件携纱器

FINITE GR0UP TABLE ACHIEVEMENT GAMES

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工程数学学报 1989年第3期 43-47页

作者： Jozsef Denes,frank Harary University of Surrey Guildfovd England. Nev Mexico State University Las Cruces USA.

Latin square achievement games were iutroduced and resolved by Hararyand Leary. In those games, a legal move places a number k between l andn in a cell of a spuare matrix for which no other cell in the same row orcolumn already contains k. The last player who can make a legal *** we introduce group table achievement games. As every finite grouptable is a latin square satisfying the "quadrangle criterion", a legalmove in this game must also satisfy the above condition. Again, the lastplayer who moves legally is the winner. We analyze group table achiementgames for order n≤6.

关键词： FINITE GR0UP TABLE ACHIEVEMENT GAMES