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Tantalum pentoxide:a new material platform for high-performance dielectric metasurface optics in the ultraviolet and visible region

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Light(Science & Applications) 2024年第1期13卷 142-152页

作者： Cheng Zhang Lu Chen Zhelin Lin junyeob Song Danyan Wang Moxin Li Okan Koksal Zi Wang Grisha Spektor David carlson Henri j.Lezec Wenqi Zhu Scott Papp Amit Agrawal School of Optical and Electronic Information&Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhanHubei 430074China National Institute of Standards and Technology GaithersburgMD 20899USA University of Maryland College ParkMD 20742USA National Institute of Standards and Technology BoulderCO 80305USA

Dielectric metasurfaces,composed of planar arrays of subwavelength dielectric structures that collectively mimic the operation of conventional bulk optical elements,have revolutionized the field of optics by their potential in constructing high-efficiency and multi-functional optoelectronic systems on *** performance of a dielectric metasurface is largely determined by its constituent material,which is highly desired to have a high refractive index,low optical loss and wide bandgap,and at the same time,be fabrication ***,we present a new material platform based on tantalum pentoxide(Ta2O5)for implementing high-performance dielectric metasurface optics over the ultraviolet and visible spectral *** wide-bandgap dielectric,exhibiting a high refractive index exceeding 2.1 and negligible extinction coefficient across a broad spectrum,can be easily deposited over large areas with good quality using straightforward physical vapor deposition,and patterned into high-aspect-ratio subwavelength nanostructures through commonly-available fluorine-gas-based reactive ion *** implement a series of highefficiency ultraviolet and visible metasurfaces with representative light-field modulation functionalities including polarization-independent high-numerical-aperture lensing,spin-selective hologram projection,and vivid structural color generation,and the devices exhibit operational efficiencies up to 80%.Our work overcomes limitations faced by scalability of commonly-employed metasurface dielectrics and their operation into the visible and ultraviolet spectral range,and provides a novel route towards realization of high-performance,robust and foundry-manufacturable metasurface optics.

关键词： dielectric optics ultraviolet

Assembly and metrology of NIF target subassemblies using robotic systems

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High Power Laser Science and Engineering 2017年第4期5卷 14-19页

作者： K.-j.Boehm N.Alexander j.a.derson L.carlson M.Farrell General Atomics P.O.Box 85608San DiegoCA 92186-5608USA

With European Laser Facilities such as the Extreme Light Infrastructure(ELI) and the Helmholtz International Beamline for Extreme Fields(HIBEF) scheduled to come online within the next couple of years, General Atomics, as a major supplier of targets and target components for the High Energy Density Physics community in the United States, is gearing up to meet their demand for large numbers of low cost targets. Using the production of a subassembly for the National Ignition Facility's fusion targets as an example, we demonstrate that through automation of assembly tasks, the design of targets and their experimental setup can be fairly complex while keeping the assembly time and cost as a minimum.A six-axis Mitsubishi robot is used in combination with vision feedback and a force–torque sensor to assemble target subassemblies of different scales and designs with minimal change of tooling, allowing for design flexibility and short assembly setup times. Implementing automated measurement routines on a Nikon NEXIV microscope further reduces the effort required for target metrology, while electronic data collection and transfer complete a streamlined target production operation that can be adapted to a large variety of target designs.

关键词： assembly automation hohlraum robotics target

joint association of physical activity/screen time and diet on CVD risk factors in 10-year-old children

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Frontiers of Medicine 2012年第4期6卷 428-435页

作者： Clemens Drenowatz joseph j.carlson Karin A.Pfeiffer joey C.Eisenmann Department of Kinesiology Michigan State UniversityEast LansingMI 48824USA Department of Radiology Division of Sports and Cardiovascular NutritionMichigan State UniversityEast LansingMI 48824USA

The increasing prevalence of childhood overweight and obesity has been associated with an increased risk for cardiovascular disease(CVD).While several studies examined the effect of single behaviors such as physical activity(PA),sedentary behavior or diet on CVD risk,there is a lack of research on combined associations,specifically in ***,the purpose of this study was to examine the joint association of PA or screen time(ST)and diet on CVD risk factors in ***,STand diet were assessed via questionnaire in 210 fifth grade students(age:10.6±0.4 years).The healthy eating index(HEI)was subsequently calculated as indicator for diet ***,weight,% body fat,and resting blood pressure were measured according to standard procedures and blood samples obtained via fingerprick were assayed for blood *** cholesterol HDL ratio(TC:HDL),mean arterial pressure(MAP),and % body fat were used as indicators of CVD risk.55% of children did not meet current PA recommendations on at least 5 days/week and 70% exceeded current recommendations for ***,only 2.5% possessed a“good”diet(HEI>80).There was no significant association of PA or STand diet on CVD risk *** TC:HDL,MAP,and % body fat nor the total CVD risk score was significantly correlated with diet,PA,or *** in the high PA group,however,had significantly better diet *** the fact that self-reported PA,ST,or dietary intake were not directly related to CVD risk in this sample,higher activity levels were associated with a healthier diet and lower ST indicating an overall healthier lifestyle of this subgroup.

关键词： exercise sedentary behavior metabolic syndrome health behavior adolescents TV time healthy eating index

EASE-DGGS:a hybrid discrete global grid system for Earth sciences

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Big Earth Data 2022年第3期6卷 340-357页

作者： jeffery A.Thompson Mary j.Brodzik Kevin A.T.Silverstein Mason A.Hurley Nathan L.carlson Minnesota Supercomputing Institute University of MinnesotaMinneapolisMNUSA GEMS Informatics Initiative University of MinnesotaMinneapolisMNUSA National Snow and Ice Data Center Cooperative Institute for Research in Environmental SciencesUniversity of ColoradoBoulderCOUSA

Although we live in an era of unprecedented quantities and access to data,deriving actionable information from raw data is a hard *** observation systems(EOS)have experienced rapid growth and uptake in recent decades,and the rate at which we obtain remotely sensed images is *** significant effort and attention has been devoted to designing systems that deliver analytics ready imagery faster,less attention has been devoted to developing analytical frameworks that enable EOS to be seamlessly integrated with other data for quantitative *** global grid systems(DGGS)have been proposed as one potential solution that addresses the challenge of geospatial data integration and ***,we propose the systematic extension of EASE-Grid in order to provide DGGS-like characteristics for EOS data *** describe the extensions as well as present implementation as an application programming interface(API),which forms part of the University of Minnesota’s GEMS(Genetic x Environment x Management x Socioeconomic)Informatics Center’s API portfolio.

关键词： Discrete global grid systems DGGS EASE Grid coordinate reference systems

Water Vapor Variability in the Tropical Western Pacific from 20-year Radiosonde Data

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Advances in Atmospheric Sciences 2001年第5期18卷 752-766页

作者： junhong Wang, Harold L. Cole and David j. carlson National Center for Atmospheric Research P. O, Box 3000,Boulder, CO 80307 National Center for Atmospheric Research Boulder USA

The 20-year (1976-1995) daily radinsonde data at 17 stations in the tropical western Pacific was ana- lyzed. The analysls shows that the atmosphere is more humid in a warmer climate on seasonal,inter-annual and long-term (20-year) time scales, implying a positive water vapor feedback The vertlcal structure of the long-term trends in relative humidity (RH) is distinct from that on short-term (seasonal and inter-annual) time scales, suggesting that observed water vapor changes on short time scales could not be considered as a surrogate of long-term climate change. The increasing trend of RH (3%-5% / decade) in the upper troposphere is stronger than that in the lower troposphere (1 %-2% / decade). Such verthal structure would amplify positive water vapor feedback in comparison to the common assumption of constant RH changes vertically. The empicical orthogonal function (EOF) analysis of vertical structure of RH varmtions shows distinct features of the vert1cal structure of the first three EOFs. The first three EOFs are optimal for repre- sentation of water vapor profiles and provide some hints on physical mechanisms respons1ble for observed humidity variability. Vaisala radiosondes were used at nine stations, and VIZ radiosondes used at other eight stations The Vaisala data are corrected for temperature-dependence error using the correction siheme developed by NCAR / ATD and Vaisala. The comparison of Vaisala and VIZ data shows that the VIZ-measured RHs after October 1993 have a moist bias of - 10% at RHs < 20%. During 1976-1995, several changes in- cluding both instruments and reporting practice have been made at Vaisala stations and introduce errors to long-term RH variations.

关键词： Water vapor Radiosonde

Tunable nano Peltier cooling device from geometric effects using a single graphene nanoribbon

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Frontiers of physics 2014年第4期9卷 472-476页

作者： Wan-ju Li Dao-Xin Yao E. W. carlson Department of Physics Purdue University West Lafayette IN 47907 USA State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-Sen University Guangzhou 510275 China

Based on the phenomenon of curvature-induced doping in graphene we propose a class of Peltier cooling devices, produced by geometrical effects, without gating. We show how a graphene nanorib- bon laid on an array of curved nano cylinders can be used to create a targeted and tunable cooling device. Using two different approaches, the Nonequilibrium Green＇s Function （NEGF） method and experimental inputs, we predict that the cooling kW/cm2, on par with the best known techniques power of such a device can approach the order of using standard superlattice structures. The structure proposed here helps pave the way toward designing graphene electronics which use geometry rather than gating to control devices.

关键词： Peltier cooling device graphene nanoribbon superlattice structure grapheneelectronics cooling power Nonequilibrium Green's Function (NI3GE)

转基因大麦中gfp基因的染色体位置及其表达(英文)

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Acta Genetica Sinica 2003年第8期30卷 697-705页

作者：陈建民 carlson A R 万建民 Kasha K j 南京农业大学农学院美国威斯康星大学农学院 wi53706 加拿大奎尔夫大学植物农学系

通过对大麦小孢子进行基因枪轰击获得 4株转绿色荧光蛋白基因 (gfp)的植株 (A、C、D、E) ,以gfp基因为探针进行荧光原位杂交 (FISH)研究转化植株中转基因插入位置和基因表达。 4个株系在染色体 7L(5HL)的不同位置都有一个插入点 ,而E株... 详细信息

通过对大麦小孢子进行基因枪轰击获得 4株转绿色荧光蛋白基因 (gfp)的植株 (A、C、D、E) ,以gfp基因为探针进行荧光原位杂交 (FISH)研究转化植株中转基因插入位置和基因表达。 4个株系在染色体 7L(5HL)的不同位置都有一个插入点 ,而E株系在染色体 5S(7HS)还有第 2个插入点。所有的转基因T0 代植株都是半合子并在T1、T2代发生分离。D株系GFP未表达 ,但FISH和PCR分析表明gfp基因已成功插入其染色体。各株系在根尖和花粉中的GFP表达水平不同 :C株系在花粉表达强而在根尖表达中等 ;A株系在花粉中等表达而在根尖表达较淡 ;E株系则在根尖高表达 ,花粉中等表达。A和C株系在根尖和花粉的GFP分离都表现单位点特性 ,而E株系的根尖分离表现重叠作用 (15∶1)特征 ,但在花粉中表达GFP的频率低。PCR结果和 3个分离株系的根尖表达结果一致。D和E株系的GFP表达不正常可能和gfp基因插入位置或基因的结构有关。

关键词：大麦绿色荧光蛋白荧光原位杂交基因表达染色体位置

Eosinophil associated genes in the inflammatory bowel disease 4 region:Correlation to inflammatory bowel disease revealed

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World journal of Gastroenterology 2012年第44期18卷 6409-6419页

作者： Kristin Blom jenny Rubin jonas Halfvarson Leif Trkvist Anders Rnnblom Per Sangfelt Mikael Lrdal Ulla-Britt jnsson Urban Sjqvist Lena Douhan Hkansson Per Venge Marie carlson Department of Medical Sciences Clinical ChemistryUppsala University HospitalSE-75185 UppsalaSweden Division of Gastroenterology Department of Intestinal Medicinerebro University HospitalSE-70185 rebroSweden School of Health and Medical Sciences rebro UniversitySE-70185 rebroSweden IBD Clinical research group Karolinska University HospitalSE-17177 StockholmSweden Department for Clinical Science Intervention and TechnologyKarolinska University HospitalSE-17177 StockholmSweden Department of Medical Sciences Gastroenterology Research GroupUppsala UniversitySE-75185 UppsalaSweden Department of Medicine Karolinska InstitutetSE-17177 StockholmSweden

AIM： To study the association between inflammatory bowel disease （IBD） and genetic variations in eosinophil protein X （EPX） and eosinophil cationic protein （ECP）. METHODS： DNA was extracted from ethylene diamine tetraacetic acid blood of 587 patients with Crohn＇s disease （CD）, 592 with ulcerative colitis （UC） and 300 healthy subjects. The EPX405 （G 〉 C, rs2013109）, ECP434 （G 〉 C, rs2073342） and ECP562 （G 〉 C, rs2233860） gene polymorphisms were analysed, by the 5＇-nuclease allelic discrimination assay. For de- termination of intracellular content of EPX and ECP in granulocytes, 39 blood samples was collected and extracted with a buffer containing cetyltrimethylam- monium bromide. The intracellular content of EPX was analysed using an enzyme-linked immunosorbent as- say. The intracellular content of ECP was analysed with the UniCAP system as described by the manufacturer. Statistical tests for calculations of results were χ2 test, Fisher＇s exact test, ANOVA, Student-Newman-Keuls test, and Kaplan-Meier survival curve with Log-rank test for trend, the probability values of P 〈 0.05 were considered statistically ***： The genotype frequency for males with UC and with an age of disease onset of ≥ 45 years （n = 57） was for ECP434 and ECP562, GG = 37%, GC = 60%, CC = 4% and GG = 51%, GC = 49%, CC = 0% respectively. This was significantly different from the healthy subject＇s genotype frequencies of ECP434 （GG = 57%, GC = 38%, CC = 5%; P = 0.010） and ECP562 （GG = 68%, GC = 29%,CC = 3%; P = 0.009）. The genotype frequencies for females, with an age of dis- ease onset of ≥ 45 years with CD （n = 62）, was for the ECP434 and ECP562 genotypes GG = 37%, GC =52%, CC = 11% and GG = 48%, GC = 47% and CC = 5% respectively. This was also statistically different from healthy controls for both ECP434 （P = 0.010） and ECP562 （P = 0.013）. The intracellular protein concen- tration of EPX and ECP was calculated in μg/10^6 eosi- nophils and then correlated to the EPX 405 genotypes

关键词： Eosinophil derived neurotoxin RNase 2 RNase 3 Single nucleotide polymorphism Inflamma-tion bowel disease Crohn's disease Ulcerative colitis

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足尺磁流变阻尼器的建模及动态特性

地震工程与工程振动 2001年第S1期21卷 8-23页

作者：杨广强 B.F Spencerjr j.D.carlson M.K. Sain 美国圣母大学土木及地质工程系 notrdarnein46556 美国LORD公司美国圣母大学电气工程系 notredamein46556

在过去三十年左右的时间里，结构保护系统受到了广大研究者的普遍关注。这种保护系统可以用来降低自然灾害（如地震、强风）对土木工程建筑的损害。由于磁流变阻尼器机械结构简单，动态范围大，能耗低、回复力大，鲁棒性良好，能够在满... 详细信息

在过去三十年左右的时间里，结构保护系统受到了广大研究者的普遍关注。这种保护系统可以用来降低自然灾害（如地震、强风）对土木工程建筑的损害。由于磁流变阻尼器机械结构简单，动态范围大，能耗低、回复力大，鲁棒性良好，能够在满足不同工程项目需求的同时提供有效的结构抗震抗风手段，目前它是一种非常有前途的半主动结构减震装置。本文首先介绍了磁流变液体和装置的主要特性和优点，建立了磁流变阻尼器的伪静力轴对称模型．并将其结果和平行板模型以及阻尼器实验结果进行了比较。尽管伪静力模型对于阻尼器的设计十分有效，但是它们还不足以描述阻尼器的动态特性。对实际工程应用来说，动态响应时间是一项非常重要的性能指标。文章还讨论了影响磁流变阻尼器动态响应时间的因素，建立了基于Ｂｏｕｃ—Ｗｅｎ模型的阻尼器动态模型。同时文章也提出了优化阻尼器动态响应的途径和方法以及其实验验证。

关键词：磁流变液体磁流变阻尼器阻尼器智能阻尼装置智能材料滞回模型参数识别系统辨识流变技术