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Electrically tunable third-harmonic generation using intersubband polaritonic metasurfaces

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Light(Science & Applications) 2024年第8期13卷 1666-1674页

作者： Seongjin Park Jaeyeon Yu Gerhard Boehm Mikhail A.Belkin Jongwon lee Department of Electrical Engineering Ulsan National Institute of Science and Technology(UNIST)UlsanRepublic of Korea Walter Schottky Institute Technical University of MunichGarchingGermany

Nonlinear intersubband polaritonic metasurfaces,which integrate giant nonlinear responses derived from intersubband transitions of multiple quantum wells(MQWs)with plasmonic nanoresonators,not only facilitate efficient frequency conversion at pump intensities on the order of few tens of kw cm^(-2)but also enable electrical modulation of nonlinear responses at the individual meta-atom level and dynamic beam *** electrical modulation characteristics of the magnitude and phase of the nonlinear optical response are realized through Stark tuning of the resonant intersubband *** this study,we report,for the first time,experimental implementations of electrical modulation characteristics of mid-infrared third-harmonic generation(THG)using an intersubband polaritonic metasurface based on MQW with electrically tunable third-order nonlinear ***,we achieved a 450%modulation depth of the THG signal,86%suppression of zero-order THG diffraction tuning based on local phase tuning exceeding 180 degrees,and THG beam steering using phase *** work proposes a new route for electrically tunable flat nonlinear optical elements with versatile functionalities.

关键词： tunable tuning pump

罗格列酮对前驱糖尿病或非糖尿病代谢综合症血浆脂联素水平和动脉僵硬度的影响

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中国动脉硬化杂志 2006年第6期14卷 510-510页

作者： Kim SG Ryu OH Kim HY lee kw Seo JA Kim NH 徐丽梅

目的噻唑烷二酮类对糖尿病患者动脉粥样硬化替代标记物如脂联素和动脉僵硬度有较好的作用.这些有益的作用是否会在非糖尿病患者(如前驱糖尿病或非糖尿病代谢综合症)出现还不明确.目前的研究是评价非糖尿病患者胰岛素致敏剂罗格列酮对... 详细信息

目的噻唑烷二酮类对糖尿病患者动脉粥样硬化替代标记物如脂联素和动脉僵硬度有较好的作用.这些有益的作用是否会在非糖尿病患者(如前驱糖尿病或非糖尿病代谢综合症)出现还不明确.目前的研究是评价非糖尿病患者胰岛素致敏剂罗格列酮对循环脂肪细胞因子水平和肱踝脉搏波传递速度的作用.方法 99例前驱糖尿病或非糖尿病患者随机分配到罗格列酮组和对照组(分别为50和49例).

关键词：细胞因子水平血浆脂联素代谢综合症罗格列酮非糖尿病动脉僵硬度抗动脉粥样硬化作用口服葡萄糖耐量高敏C反应蛋白糖尿病患者

Evaluation of the string test for the detection of Helicobacter pylori

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World Journal of Gastroenterology 2003年第2期9卷 309-311页

作者： Rupert WL Leong Ching C lee Thomas kw Ling WaiK Leung Joseph JY Sung Department of Gastroenterology University of New South WalesBankstown HospitalSydneyAustralia Department of Microbiology Chinese University of Hong Kong Prince of Wales HospitalShatinHong KongChina Department of Medicine & Therapeutics Chinese University of Hong KongPrince of Wales HospitalShatinHone KongChina

AIM: Helicobacter pylori can be diagnosed by invasive ornon-invasive tests but to obtain bacteria for culture andantibiotic susceptibility testing, an upper GI endoscopy isoften required. The string test may be a minimally-invasivealternative method of obtaining H. pylori samples. This studyevaluates the sensitivity and specificity of the string test inthe diagnosis of H. pylori in comparison with endoscopicmeans of ***: This was a prospective open comparative studyof patients with dyspepsia with endoscopy-based tests asgold standard (defined as a positive CLO test and antralhistology). Fasting patients swallowed the encapsulated-string(Entero-test Hp), which was withdrawn after 1 hour. Thegastric juice from the string was plated onto H. pylori-selectivemedia for culture. Helicobacter pylori was identified by typicalcolony morphology, gram stain and biochemical test ***: Thirty dyspeptic patients were recruited of whom21 (70 %) were positive for H. pylori according to the goldstandard. The sensitivity, specificity, positive predictive value,and negative predictive value for the string test were 38 %,100 %, 100 % and 41% respectively, and for endoscopicbiopsies 81%, 100 %, 100 %, 69 % respectively (P=0.004).Logistic regression showed that only abundant growthdensity from endoscopic biopsy cultures to be a predictor ofa positive string test (P=0.018).CONCLUSION: The string test is an alternative method toendoscopy in obtaining H. pylori but has a low sensitivitycompared to endoscopic biopsies.

关键词：幽门螺杆菌活组织检查消化道溃疡细菌培养内窥镜无创性检查

Design of low noise airfoil with high aerodynamic performance for use on small wind turbines

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Science China(Technological Sciences) 2010年第1期53卷 75-79页

作者： Taehyung KIM Seungmin lee Hogeon KIM Soogab lee Department of Mechanical and Aerospace Engineering Seoul National University599 Gwanak-roGwanak-guSeoul 151-742Republic of Korea

Wind power is one of the most reliable renewable energy sources and internationally installed capacity is increasing radically every *** wind power has been favored by the public in general,the problem with the impact of wind turbine noise on people living in the vicinity of the turbines has been *** noise wind turbine design is becoming more and more important as noise is spreading more adverse effect of wind turbine to *** paper demonstrates the design of 10 kw class wind turbines,each of three blades,a rotor diameter 6.4 m,a rated rotating speed 200 r/min and a rated wind speed 10 m/*** optimized airfoil is dedicated for the 75% spanwise position because the dominant source of a wind turbine blade is trailing edge noise from the outer 25% of the *** computations are performed for incompressible flow and for Mach number at 0.145 and for Reynolds numbers at 1.02×106 with a lift performance,which is resistant to surface contamination and turbulence *** objectives in the design process are to reduce noise emission,while sustaining high aerodynamic *** broadband noise sources are predicted by semi-empirical formulas composed of the groundwork by Brooks et *** Lowson associated with typical wind turbine operation *** the airfoil redesign process,the aerodynamic performance is analyzed to reduce the wind turbine power *** results obtained from the design process show that the design method is capable of designing airfoils with reduced noise using a commercial 10 kw class wind turbine blade airfoil as a ***,the new optimized airfoil showing 2.9 dB reductions of total sound pressure level(SPL) and higher aerodynamic performance are achieved.

关键词： wind turbine aerodynamic noise airfoil self noise low noise airfoil design

High‑Defect‑Density Graphite for Superior‑Performance Aluminum‑Ion Batteries with Ultra‑Fast Charging and Stable Long Life

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Nano-Micro Letters 2021年第11期13卷 168-189页

作者： Jisu Kim Michael Ruby Raj Gibaek lee Advanced Energy Materials Design Lab School of Chemical EngineeringYeungnam UniversityGyeongsan 38541Republic of Korea

Rechargeable aluminum-ion batteries(AIBs)are a new generation of low-cost and large-scale electrical energy storage ***,AIBs suffer from a lack of reliable cathode materials with insufficient intercalation sites,poor ion-conducting channels,and poor diffusion dynamics of large chloroaluminate anions(AlCl4−and Al2Cl7−).To address these issues,surfacemodified graphitic carbon materials[i.e.,acidtreated expanded graphite(AEG)and base-etched graphite(BEG)]are developed as novel cathode materials for ultra-fast chargeable *** has more turbostratically ordered structure covered with abundant micro-to nano-sized pores on the surface structure and expanded interlayer distance(d002=0.3371 nm)realized by surface treatment of pristine graphite with acidic media,which can be accelerated the diffusion dynamics and efficient AlCl4−ions(de)-intercalation *** AIB system employing AEG exhibits a specific capacity of 88.6 mAh g^(−1)(4 A g^(−1))and~80 mAh g^(−1) at an ultra-high current rate of 10 A g^(−1)(~99.1%over 10,000 cycles).BEG treated with KOH solution possesses the turbostratically disordered structure with high density of defective sites and largely expanded d-spacing(d002=0.3384 nm)for attracting and uptaking more AlCl4−ions with relatively shorter penetration ***,the AIB system based on the BEG cathode delivers a high specific capacity of 110 mAh g^(−1)(4 A g^(−1))and~91 mAh g^(−1)(~99.9%over 10,000 cycles at 10 A g^(−1)).Moreover,the BEG cell has high energy and power densities of 247 Wh kg^(−1) and 44.5 kw kg^(−1).This performance is one of the best among the AIB graphitic carbon materials reported for chloroaluminate anions storage *** finding provides great significance for the further development of rechargeable AIBs with high energy,high power density,and exceptionally long life.

关键词： Surface modification Etched graphite Cathode materials Energy storage Aluminum-ion batteries

Experimental Study of Rotational Effect on Stalling

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Chinese Physics Letters 2013年第6期30卷 123-126页

作者： lee Hsiao Mun WU Yan-Hua School of Mechanical and Aerospace Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798

Tomographic particle image velocimetry(TPIV)and static pressure measurements are performed in a wind tunnel on a scaled model of the rotor blade of a 5 kw horizontal-axis wind turbine designed by using the blade element momentum *** study is to investigate the physics of the stall-delay phenomenon observed for a rotating *** TPIV experiments are conducted at several span-wise locations of the *** separated flow from the rotating blade is studied and compared with the case of the static stall at similar angles of attack and Reynolds number Re.

关键词： method. blade rotating

Brassiere wearing and breast cancer risk:A systematic review and meta-analysis

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World Journal of Meta-Analysis 2015年第4期3卷 193-205页

作者： Winnie kw So Dorothy NS Chan Yan Lou Kai-Chow Choi Carmen WH Chan Kristina Shin Ava kwong Diana TF lee The Nethersole School of Nursing The Chinese University of Hong KongNew Territories Nursing Department School of MedicineHangzhou Normal University Institute of Textiles and Clothing the Hong Kong Polytechnic University Breast Surgery Division Department of SurgeryQueen Mary Hospital

AIM： To evaluate existing evidence for the association between different type of brassiere exposures and the risk of breast ***： Ovid Medline, CINAHL, Cochrane Data Base of Systematic Reviews, Pubmed, Scopus, Proquest, Sciencedirect, Wiley Online Library, WanFang Data, Hong Kong Index to Chinese Periodicals, China Journal Net, Chinese Medical Current Contents, Chinese Biomedical Literature Database, China Academic Journals Full-Text database, Taiwan Electronic Periodical Services and HyRead; reference lists of published studies; origi-nal research studies published in English or Chinese examining the association between type and duration of brassiere-wearing and breast cancer risk. Data were abstracted by a frst reviewer and verifed by a second. Study quality was rated according to predefned criteria. “Fair” or “good” quality studies were included. Results were summarised by meta-analysis whenever adequate material was ***： Twelve case-control studies were included in the review. Meta-analysis showed brassiere wearing during sleep was associated with a two times ofincreased odds. CONCLUSION： The present review demonstrates insuffcient evidence to establish a positive association between the duration and type of brassiere wearing and breast cancer. Further research is essential; specifcally, a large-scale epidemiological study of a better design is needed to examine the association between various forms of brassiere exposure in detail and breast cancer risk, with adequate control of confounding variables.

关键词： Breast cancer Brassiere Risk factors Systematic review Meta-analysis

Plasma density measurement and downstream etching of silicon and silicon oxide in Ar/NF3 mixture remote plasma source

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Plasma Science and Technology 2019年第6期21卷 52-57页

作者： H J YEOM D H CHOI Y S lee J H KIM D J SEONG S J YOU H C lee Korea Research Institute of Standards and Science(KRISS) Daejeon 34113 Republic of Korea Department of Physics Chungnam National University Daejeon 34134 Republic of Korea

In this study,plasma density measurements were performed near the plume region of the remote plasma source (RPS) in Ar/NF3 gas mixtures using a microwave cutoff *** measured plasma density is in the range of 1010-1011 cm-3 in the discharge conditions with RPS powers of 2-4 kw and gas pressures of 0.87-4 *** plasma density decreased with increasing gas pressures and RPS powers under various Ar/NF3 mixing *** decrease in the plasma density measured at the fixed measurement position (plume region) can be understood by the reduction of the electron energy relaxation length with increases in the gas pressures and mixing ratio of NF3/(Ar/NF3).We also performed downstream etching of silicon and silicon oxide films in this *** etch rate of the silicon films significantly increases while the silicon oxide is slightly etched with the gas pressures and *** was also found that the etch rate strongly depends on the wafer position on the processing chamber electrode,and that the etch selectivity reached 96-131 in the discharge conditions of RF powers (3730-4180 W) and gas pressures (3.6-4 Torr).

关键词： remote plasma source electron density cutoff probe downstream etch

Insufficient neovascularization and increased vascular permeability during inadequate repair of steroid-associated osteonecrosis lesion in a rabbit model

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Insufficient neovascularization and increased vascular perme...