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Gyrokinetic theory of turbulent acceleration and momentum conservation in tokamak plasmas

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Plasma Science and Technology 2018年第7期20卷 22-26页

作者： Lu WANG Shuitao PENG P H diamond International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma Physics State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic Engineering Huazhong University of Science and Technology Wuhan 430074 People's Republic of China Center for Momentum Transport and Flow Organization and Center for Astrophysics and Space Sciences University of California at San Diego La Jolla CA 92093-0424 United States of America

Understanding the generation of inmnsic rotation in tokamak plasmas is crucial for future fusion reactors such as ITER. We proposed a new mechanism named turbulent acceleration for the origin of the intrinsic parallel rotation based on gyrokinetic theory. The turbulent acceleration acts as a local source or sink of parallel rotation, i.e., volume force, which is different from the divergence of residual stress, i.e., surface force. However, the order of magnitude of turbulent acceleration can be comparable to that of the divergence of residual stress for electrostatic ion temperature gradient （ITG） turbulence. A possible theoretical explanation for the experimental observation of electron cyclotron heating induced decrease of co-current rotation was also proposed via comparison between the turbulent acceleration driven by 1TG turbulence and that driven by collisionless trapped electron mode turbulence. We also extended this theory to electromagnetic ITG turbulence and investigated the electromagnetic effects on intrinsic parallel rotation drive. Finally, we demonstrated that the presence of turbulent acceleration does not conflict with momentum conservation.

关键词： turbulent acceleration intrinsic rotation momentum conservation

“我们永远都是道德主义者”——艾瑞斯·默多克、事实及价值

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当代中国价值观研究 2024年第4期9卷 95-115页

作者：科拉·戴蒙德卢俊豪(译) 弗吉尼亚大学中山大学哲学系

通过重构默多克对黑尔等分析哲学家的批判,本文深入分析了默多克的道德哲学理论以及她对事实与价值区分的不同理解方式,阐明了道德价值与个体认知活动的关系。在默多克看来,个体在感知世界、对待事物时带有一种“一般观念态度”,因此,... 详细信息

通过重构默多克对黑尔等分析哲学家的批判,本文深入分析了默多克的道德哲学理论以及她对事实与价值区分的不同理解方式,阐明了道德价值与个体认知活动的关系。在默多克看来,个体在感知世界、对待事物时带有一种“一般观念态度”,因此,我们观看外部的视角和注意力始终受到道德的指引;我们的道德本质是无处不在的,不仅渗透在我们的日常意识中,而且表现在我们的所有意识模式中。我们天生就是道德存在者,永远受道德价值的引导,这些道德价值不仅影响着我们的一切认知,而且塑造着我们的“境界”与“选择”。

关键词：事实价值境界道德主义道德语言认知活动

Cirrhosis complicating Shwachman-diamond syndrome: A case report

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World Journal of Clinical Cases 2019年第12期7卷 1456-1460页

作者： sandra M Camacho Lucille McLoughlin Michael J Nowicki Division of Pediatric Gastroenterology University of Mississippi Medical Center Jackson MS 39216 United States Division of Pediatric Gastroenterology Children’s Hospital of San Antonio San Antonio TX 78207 United States

BACKGROUND The features of Shwachman-diamond syndrome (SDS) include exocrine pancreatic insufficiency, skeletal abnormalities and bone marrow dysfunction;an often overlooked feature is hepatic involvement. CASE SUMMARY We report a child who initially presented with failure to thrive and mildly elevated transaminase levels and was determined to have pancreatic insufficiency due to SDS. During follow-up he had persistently elevated transaminase levels and developed hepatosplenomegaly. An investigation was performed to determine the etiology of ongoing liver injury, including a liver biopsy which revealed hepatic cirrhosis. CONCLUSION Cirrhosis has rarely been reported with SDS. While many of the hepatic disorders associated with SDS improve with age, there are rare exceptions with serious implications for long-term outcome.

关键词： Shwachman-diamond syndrome Cirrhosis Liver dysfunction Case report

The Janus of macrophysiology： stronger effects of evolutionary history, but weaker effects of climate on upper thermal limits are reversed for lower thermal limits in ants

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Current Zoology 2018年第2期64卷 223-230页

作者： Sarah E. diamond Lacy D. CHICK Department of Biology Case Western Reserve University Cleveland OH 44106 USA

Species may exhibit similar traits via different mechanisms： environmental filtering and local adaptation （geography） and shared evolutionary history （phylogeny） can each contribute to the resemblance of traits among species. Parsing trait variation into geographic and phylogenetic sources is important, as each suggests different constraints on trait evolution. Here, we explore how phylogenetic distance, geographic distance, and geographic variation in climate shape physiological tolerance of high and low temperatures using a global dataset of ant thermal tolerances. We found generally strong roles for evolutionary history and geographic variation in temperature, but essen- tially no detectable effects of spatial proximity per se on either upper or lower thermal tolerance. When we compared the relative importance of the factors shaping upper and lower tolerances, we found a much stronger role for evolutionary history in shaping upper versus lower tolerance, and a moderately weaker role for geographic variation in temperature in shaping upper tolerance when compared with lower tolerance. Our results demonstrate how geographic variation in climate and evolutionary history may have differential effects on the upper and lower endpoints of physiological tolerance. This Janus effect, where the relative contributions of geographic variation in climate and evolutionary history are reversed for lower versus upper physiological tolerances, has gained some support in the literature, and our results for ant physiological tolerances provide further evidence of this pa^ern. As the climate continues to change, the high phylogenetic conservatism of upper tolerance may suggest potential constraints on the evolution of tolerance of high temperatures.

关键词： biogeography evolutionary history latitudinal cline macrophysiology temperature thermal tolerance.

A comparative study on the performances of synthetic diamond made by belt press & cubic press

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金刚石与磨料磨具工程 2008年第S1期28卷 50-55页

作者： Jia Pan~1,Lu Canhua~1,Ye Hongyu~2,Li Zhihong~3 (1.Nanyang Zhongnan diamond Co.,Ltd.Nanyang,China) (2.Wuhan Wanbang Laser diamond Tools Co.,Wuhan,China) (3.Industrial diamond Association of China,Zhengzhou 450013,China )

There are mainly two kinds of equipment to produce synthetic diamond,namely belt press & cubic *** has been customary in the industry to regard synthetic diamond produced by cubic press is inferior to that made by belt *** the on-going improvement in technology,know-how & accumulated experiences, perhaps it’ s time for us to review the qualities & performances of synthetic diamond made by the cubic press more *** were carried out on the performances of the two kinds of diamond by choosing from top brands & top qualities,with coarser mesh sizes 20/30 & 30/*** were made on parameters, such as TI,TTI,PPC,bulk density,compact,roughness and *** the diamonds chosen were used to produce the relevant diamond core drill bits and saw blades,their respective cutting performances such as cutting efficiency,segments consumption were measured and reported in this *** report demonstrates that producing the high quality diamond does not depend on the type of presses(Belt or Cubic) but rather on the know-how,technology and what it is made.

关键词： comparative study,performance,synthetic diamond belt press,cubic press

Current practices and future prospects for the management of gallbladder polyps: A topical review

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World Journal of Gastroenterology 2018年第26期24卷 2844-2852页

作者： R Stephen McCain Anna diamond Claire Jones Helen G Coleman Centre for Public Health Institute of Clinical Sciences Queens University Belfast Ulster Hospital South Eastern Health and Social Care Trust Mater Hospital Belfast Health and Social Care Trust Queens University Belfast Centre for Public Health Queen’s University Belfast

A gallbladder polyp is an elevation of the gallbladder mucosa that protrudes into the gallbladder lumen. Gallbladder polyps have an estimated prevalence in adults of between 0.3%-12.3%. However, only 5% of polyps are considered to be "true" gallbladder polyps, meaning that they are malignant or have malignant potential. The main radiological modality used for diagnosing and surveilling gallbladder polyps is transabdominal ultrasonography. However, evidence shows that other modalities such as endoscopic ultrasound may improve diagnostic accuracy. These are discussed in turn during the course of this review. Current guidelines recommend cholecystectomy for gallbladder polyps sized 10 mm and greater, although this threshold is lowered when other risk factors are identified. The evidence behind this practice is relatively low quality. This review identifies current gaps in the available evidence and highlights the necessity for further research to enable better decision making regarding which patients should undergo cholecystectomy, and/or radiological follow-up.

关键词： Gallbladder polyps Gallbladder cancer True polyps Pseudo polyps

Preoperative nuclear stress testing in the very old patient population

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World Journal of Cardiology 2020年第5期12卷 210-219页

作者： Amgad N Makaryus John N Makaryus Joseph A diamond Department of Cardiology Northwell HealthNew Hyde ParkNY11042United States Department of Cardiology Nassau University Medical CenterEast MeadowNY 11554United States

BACKGROUND Elderly patients awaiting moderate to high-risk surgery may undergo nuclear stress testing(NST)in order to evaluate their cardiovascular *** prognostic utility of such testing in the very elderly(≥85 years)has yet to be fully *** and nonogenarians frequently have a number of concurrent conditions including a high rate of coronary disease,and therefore the prognostic value of NST for their preoperative risk assessment has been *** evaluation assesses the ability of nuclear stress testing to predict peri-operative cardiac outcomes in this patient *** To investigate the ability of NST to predict peri-operative cardiac outcomes in elderly patients awaiting moderate to high-risk *** Patients≥85 years undergoing pre-operative NST were retrospectively *** undergoing low-risk surgery were *** adverse cardiac events(MACE)were considered any adverse event that occurred prior to discharge and included acute heart failure,arrhythmia,acute myocardial infarction,unstable angina,or *** between patient risk factors,MACE,and the obtained results of the pre-operative stress testing,ejection fraction(0)were *** A total of 69 patients(mean age 88±2.6 years,31 males)underwent nuclear stress testing prior to *** were 41(60%)patients found to have an abnormal ***(23%)patients were noted to experience post-operative *** significant associations between risk factors and MACE were *** with an abnormal NST and/or a summed stress score≥9 weresignificantly(P<0.01)more likely to develop peri-operative *** Indicated preoperative NST is useful to assess pre-operative risk in elderly patients≥85 years undergoing moderate to high-risk surgery.

关键词： Pharmacologic nuclear stress testing Prognosis Elderly Preoperative assessment Outcomes

Clinical outcome of pediatric and young adult subclinical varicoceles:a single-institution experience

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Asian Journal of Andrology 2021年第6期23卷 611-615页

作者： Patricia S Cho Richard N Yu Harriet J Paltiel Matthew A Migliozzi Xiaoran Li Alyssia Venna David A diamond Department of Urology University of Massachusetts Medical SchoolWorcesterMA 01655USA Department of Urology Boston Children's HospitalBostonMA 02115USA Department of Radiology Boston Children's HospitalBostonMA 02115USA

Subclinical varicocele represents an abnormality of veins of the pampiniform plexus on scrotal ultrasound(US)without a clinically palpable *** significance remains *** guidelines do not recommend surgical intervention,clinical management is *** there is limited information on long-term outcome of subclinical varicoceles due to challenges in diagnosis and management,we performed a single-institution,retrospective review of patients from October 1999 to October 2014 with subclinical varicocele and with available US studies reviewed by a single *** varicocele was defined as dilation of the pampiniform venous plexus on US involving≥2 vessels with diameter>2.5 mm,without clinical varicocele on physical examination or prior inguinal ***-six of 98 patients identified were confirmed as having a subclinical varicocele and *** mean age at initial visit was 15.5 years,with a mean follow-up of 26.5 *** majority were right-sided(69.4%,n=25),usually with a contralateral clinical *** asymmetry(>20%volume difference of the affected side by testicular atrophy index formula)was assessed in 9 patients with unilateral subclinical varicocele without contralateral clinical or subclinical varicocele and observed in 1 *** 17 patients with follow-up,3(17.6%)progressed to clinical varicocele without asymmetric testicular volume,as most remained subclinical or resolved without *** our experience,subclinical varicoceles appeared unlikely to progress to clinical varicoceles,to affect testicular volume,or to lead to *** our study is limited in numbers and follow-up,this information may aid clinical management strategies and guide future prospective studies.

关键词： adolescent pediatric subclinical varicocele

Properties of SN Ia progenitors from light curves and spectra

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Frontiers of physics 2013年第2期8卷 144-167页

作者： P. Hoflich P. Dragulin J. Mitchell B. Sadler T. diamond C. Gerardy Department of Physics Florida State University Talahassee USA FL 32306 Department of Physics Astronomy Clemson University Clemson USA SC 29634

With recent advances in theory and observations, direct connections emerge between the progenitors of Type Ia Supernovae （SNe Ia） and the observed light curves and spectra. A direct link is important for our understanding of the supernovae physics, the diversity of SNe Ia and the use of SNe Ia for high-precision cosmology because the details of the explosion depends sensitively on the initial conditions and the explosion scenario（s） realized in nature. Do SNe Ia originate from SD- or DD systems, and do they lead to Mcu mass explosions or dynamical mergers？ Does the statistical distribtion of SNe Ia depend on their environment which can be expected to change with redshift？ In this contribution, we will exam from the theoretical point of view the tell-tails for this connection, their consistency with the observations, and future directions. In a first section, we present the physics of the explosion, light curves and spectral formation in a nutshell to help understanding the connection. For details of the progenitor evolution and explosion physics, we refer to reviews and the other contributions in this issue. Each of the topical sections starts with a brief general review followed by a more detailed discussion of specific results. Because the youth of the field, some bias is unavoidable towards results obtained within our collaborations （and FSU）. The imprint of the metallicity, progenitor stars and properties such as the central density of the exploding WD are presented. IR spectroscopy, polarimetry and imaging of SNR remnants are discussed as a tool to test for the WD properties, magnetic fields and asymmetries. We discuss different classes of Type Ia supernovae, and their environment. Possible correlations between the spectroscopic and light curve properties of SN Ia are discussed. Finally, the overall emerging picture and future developments are discussed.

关键词： supernovae: general progenitors light curves spectra