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喷流对飞机尾流涡影响的试验研究

航空学报 2010年第5期31卷 899-908页

作者：黄烁桥申功忻 Robert Konrath carl F.v. Carmer Kompenhans jurgen 北京航空航天大学航空科学与工程学院北京100191 德国宇航院气动与流动技术研究所哥廷根37073

飞机产生的尾流涡,特别是大尺度的翼尖涡,对尾随其后的飞行器是非常有害的,本文旨在探索利用飞机发动机产生的喷流加速尾流涡消亡的方法。试验采用简化的飞机模型(有尾翼),建立了包含一对翼尖涡及一对反向旋转的尾翼涡(通过以负迎角安... 详细信息

飞机产生的尾流涡,特别是大尺度的翼尖涡,对尾随其后的飞行器是非常有害的,本文旨在探索利用飞机发动机产生的喷流加速尾流涡消亡的方法。试验采用简化的飞机模型(有尾翼),建立了包含一对翼尖涡及一对反向旋转的尾翼涡(通过以负迎角安装尾翼得到)的4涡尾流系统。在无外来扰动的情况下,不同的尾翼设置下得到的尾翼涡对翼尖涡的作用效果不同,有的能导致翼尖涡提前消亡,有的则不能。考察了不同强度的喷流对不同4涡尾流系统的影响,且作为对比,对无尾翼(2涡系统)及无喷流下的各种情况也分别作了观测。试验在拖曳水槽中进行,运用体视粒子图像测速(SPIV)技术,观测了与模型拖曳方向垂直的、从机翼后缘到下游约45翼展间均布的一系列切面。结果表明:当喷流直接作用于涡时,其效果主要取决于两者之间的初始距离及相对强度;而当喷流作用于整个4涡尾流系统时,其引入的扰动对不同的系统均能起到一定程度的改善作用,这种作用的关键在于利用喷流优化对翼尖涡进行扰动的机制,而不仅仅取决于喷流的强度。

关键词：流体力学飞机尾流喷流体视粒子图像测速

Day to Day Consistency and Inter-subject Variability of Neuromuscular Responses and Performance Fatigability as the Result of Maximal,Bilateral,Dynamic Leg Extensions

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journal of Science in Sport and Exercise 2021年第2期3卷 195-204页

作者： joshua L.Keller Terry j.Housh john Paul V.Anders Cory M.Smith Ethan C.Hill Richard j.schmidt Glen O.johnson Exercise Physiology Laboratory University of Nebraska-Lincoln1740 Vine StreetLincolnNE 68508USA Department of Kinesiology Human and Environmental Physiology LaboratoryUniversity of Texas At El PasoEl PasoTX 79968USA School of Kinesiology and Physical Therapy Division of KinesiologyUniversity of Central FloridaOrlandoFL 32816USA

Purpose The purpose of the present study was to examine the day-to-day consistency and inter-subject variability of com-posite and individual,neuromuscular and torque patterns of responses as a result of a fatiguing bout of maximal,bilateral,isokinetic leg extension muscle *** Ten men (Mean ± SD =21.6 ± 2.5 years) completed two testing visits consisting of pretest and posttest maximal voluntary isometric contractions (MVIC) as well as 25 maximal,bilateral,isokinetic (180°/s),leg extension muscle *** (EMG) and mechanomyographic (MMG) signals were collected from the vastus lateralis and normalized to the *** fatigability was defined as the percent decline in torque between the average of repetitions 1,2,and 3 and repetitions 23,24,and *** regression was used to examine the individual and composite relation-ships between EMG amplitude (AMP),EMG mean power frequency (MPF),MMG AMP,MMG MPF,and torque versus *** There was no significant difference (d =0.80;P =0.17) in the performance fatigability between Day 1 (19.3% ± 7.1%)and Day 2 (26.9% ± 11.3%).Polynomial regression indicated substantial inter-subject variability,but high day-to-day *** The composite EMG AMP,MMG AMP,and MMG MPF patterns of responses demonstrated consistency across *** composite EMG MPF patterns of responses,however,were not consistent between Day 1 and Day *** addition,based on the high inter-subject variability,future studies should present both composite patterns of neuromuscular responses and the patterns of responses on a subject-by-subject basis to make inferences regarding fatigue-induced changes in motor unit activation strategies.

关键词： Performance fatigability Electromyography Mechanomyography Bilateral Dynamic

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电视制作的声像同步及技术改进

广播与电视技术 1989年第4期16卷 64-70页

作者：李宁

本文讨论了在制作电视节目中存在的声音和图像的同步问题及其对于观众的影响,并介绍了改进A/V同步的方法。

关键词：电视节目声像同步 A/V同步制作

The Evolving Role of Botanical Gardens and Natural Areas:A Floristic Case Study from Royal Botanical Gardens,Canada

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植物分类与资源学报 2011年第1期33卷 123-131页

作者： David A.GALBRAITH Natalie E.IWANYCKI Brechann V.McGOEY jamie McGREGOR james S.PRINGLE carl j.ROTHFELS Tyler W.SMITH Royal Botanical Gardens BurlingtonON University of Guelph GuelphON Duke University DurhamNC Eastern Kentucky University RichmondKY

As leaders calling for the conservation of the world's plants,botanical gardens protect plants within living *** also study,manage and restore plants in natural *** Botanical Gardens(Ontario,Canada) has integrated both horticultural and natural heritage in its mission for *** by municipal leaders in the 1920s as a combination of nature sanctuaries and civic gardens,RBG now includes forests,wetlands and other habitats,gardens and built *** RBG is Canada's largest botanical garden on the basis of *** the 1950s RBG began to inventory plant *** checklist of spontaneous vascular plants now exceeds 1 170 species,of which 752 are *** is 37% of Ontario's native vascular plants and 19% of the native vascular flora of *** RBG nature sanctuaries are among the richest locations in Canada for species-level *** examine the history of floristic exploration within RBG and compare plant species-area relationships among protected natural areas in *** comparison supports the contention that the nature sanctuaries,and in particular Cootes Paradise,could be considered an important area for plants in Canada,and relative to the nation's flora,a biodiversity *** fact that a candidate vascular plant hotspot for Canada lies within a major botanical garden presents opportunities for raising public awareness of the importance of plant diversity,as well as focusing attention on the scientific and conservation biology needs of communities and individual species in this area.

关键词： Botanical garden Ontario Natural areas Biodiversity Species-area curve Species richness

Spatial and spectral mode mapping of a dielectric nanodot by broadband interferometric homodyne scanning near-field spectroscopy

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Advanced Photonics 2020年第4期2卷 55-65页

作者： jinxin Zhan Wei Wang jens Brauer Lukas schmidt-Mende Christoph Lienau Petra Groß carl von Ossietzky Universität Institut für Physik and Center of Interface ScienceOldenburgGermany University of Konstanz Department of PhysicsKonstanzGermany

We investigate the optical properties of nanostructures of antimony sulfide(Sb2S3),a direct-bandgap semiconductor material that has recently sparked considerable interest as a thin film solar cell *** from a nanoparticle ink solution and two-and three-dimensional nanostructuring with pattern sizes down to 50 nm have recently been *** into the yet unknown nanoscopic optical properties of these nanostructures is highly desired for their future applications in *** implement a spectrally broadband scattering-type near-field optical spectroscopy technique to study individual Sb2S3 nanodots with a 20-nm spatial resolution,covering the range from 700 to 900 *** show that in this below-bandgap range,the Sb2S3 nanostructures act as high-refractive-index,low-loss waveguides with mode profiles close to those of idealized cylindrical waveguides,despite a considerable structural *** combination with their high above-bandgap absorption,this makes them promising candidates for applications as dielectric metamaterials,specifically for ultrafast photoswitching.

关键词： near-field spectroscopy scattering-type near-field optical microscopy tip-modulation SNOM dielectric nanostructure thin film patterning

鸡乙酰胆碱受体γ亚基基因5′连接区含多元顺式调节元件

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生物化学杂志 1992年第6期8卷 676-679页

作者：贾弘禔 j.schmidt 北京医科大学生物化学教研室 Dept.of Biochemistry and Cell Biology SUNY at Stony BrookNY11794

本工作利用瞬时表达研究了鸡Ach Rγ亚基基因5′连接区的调控机能。CAT分析表明,γ基因5′连接区-509/-302和-324/+36序列均可独立激活SV40启动子的转录,这种激活作用具有组织特异性,与方向、距离无关,符合增强子样作用。

关键词：乙酰胆碱受体 γ亚基基因

The Utility of Procalcitonin as a Biomarker to Limit the Duration of Antibiotic Therapy in Adult Sepsis Patients

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Surgical Science 2014年第8期5卷 342-353页

作者： Ronald S. Chamberlain Brian j. Shayota carl Nyberg Prasanna Sridharan Department of Surgery Saint Barnabas Medical Center Livingston USA

Introduction: With rising global antibiotic resistance, stewardship programs aimed at controlling multi-drug resistant (MDR) pathogens have begun to gain acceptance. These programs stress appropriate antibiotic selection, dosage and duration. A growing literature suggests serum procalcitonin (PCT) levels may be useful in guiding antibiotic duration and de-escalation. This report sought to evaluate the evidence-based data available from prospective randomized controlled trials (RCT) on the role of PCT in guiding reductions in antibiotic duration in adult sepsis patients. Methods: A comprehensive search of all published prospective RCT(s) on the use of PCT as a tool for guiding antibiotic therapy in adult sepsis patients was conducted using PubMed, Medline Plus and Google Scholar (2007-2013). Keywords searched included, “procalcitonin”, “sepsis-therapy”, “sepsis biomarker”, “antibiotic duration”, “drug de-escalation”, and “antimicrobial stewardship”. Results:?Four RCT(s) involving 826 adult sepsis patients have evaluated the role of serum PCT levels to guide criteria for cessation of antibiotic therapy based either on specific PCT levels or PCT kinetics. Bouadma?et al.?(N = 621) stopped antibiotics when the PCT concentration was 1 ng/mL. The PCT arm showed a 2-day reduction in antibiotics. Finally, Nobre?et al.?(N = 68) stopped antibiotics when PCT levels decreased by 90% or more from the initial value, but not prior to Day 3 (if baseline PCT measured <1 μg/

关键词： Procalcitonin Sepsis Therapy Sepsis Biomarker Antibiotic Duration Antibiotic De-Escalation Antimicrobial Stewardship

STIM1 expression is associated with osteosarcoma cell survival

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Chinese journal of Cancer Research 2019年第1期31卷 203-211页

作者： jie Zang Dongqing Zuo Kristen L.Shogren carl T.Gustafson Zifei Zhou Michael A Thompson Ruiwei Guo Y.S.Prakash Lichun Lu Wei Guo Avudaiappan Maran Michael j.Yaszemski Department of Orthopedic Surgery Mayo ClinicRochesterMN 55905USA Musculoskeletal Tumor Center Peking University People's HospitalBeijing 100044China Department of Orthopaedics Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 200080China Department of Anesthesiology Mayo ClinicRochesterMN 55905USA Department of Cardiology Kunming General Hospital of Chengdu Military Command of PLA Department of Physiology and Biomedical Engineering Mayo ClinicRochesterMN 55905USA

Objective: To examine the role of store-operated calcium entry(SOCE) and stromal interaction molecule 1(STIM1) in survival and migration of osteosarcoma cells and investigate what blockade of store-operated Ca^(2+)contributes to the regulation of osteosarcoma ***: First, we examined the expression levels of STIM1 in osteosarcoma cell lines by Western analysis and in tissue specimens by immunohistochemistry. Second, we investigated the effect of SOCE and STIM1 on osteosarcoma cell viability using MTS assays and on cell proliferation using colony formation. Third, we investigated the role of SOCE and STIM1 in cell migration using wound healing assays and Boyden chamber assays. Finally, we studied the effect of SOCE on the nuclear factor of activated T-cells cytoplasmic 1(NFATc1)activity by luciferase ***: STIM1 was overexpressed in osteosarcoma cell lines and tissue specimens and was associated with poor survival of osteosarcoma patients. Also, inhibition of SOCE and STIM1 decreased the cell viability and migration of osteosarcoma cells. Furthermore, our results showed that blockade of store-operated Ca^(2+) channels involved down-regulation of NFATc1 in osteosarcoma ***: STIM1 is essential for osteosarcoma cell functions, and STIM1 and Ca^(2+) entry pathway could be further explored as molecular targets in the treatment of osteosarcoma.

关键词： Calcium NFATc1 osteosarcoma SOCE STIM1

The modifying influence of HLA classⅡDQB1^(*)06:02 on the Streptococcus and clinical phenotype correlation among anti-Ro+mothers of children with neonatal lupus

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Genes & Diseases 2023年第4期10卷 1169-1171页

作者： Robert M.Clancy carla j.Guthridge Miranda C.Marion joel Guthridge Timothy D.Howard Peter M.Izmirly Mala Masson jill P.Buyon judith A.james carl D.Langefeld Department of Medicine Division of RheumatologyNYU Grossman School of MedicineNew YorkNY 10016USA Arthritis and Clinical Immunology Oklahoma Medical Research FoundationOklahoma CityOK 73104USA Department of Biostatistics and Data Science Wake Forest School of MedicineWinstone SalemNC 27101USA Center for Precision Medicine Wake Forest School of MedicineWinstoneSalemNC 27101USA Department of Biochemistry Wake Forest School of MedicineWinstoneSalemNC 27101USA

The genus Streptococcus,a gram-positive bacterium,con-tains species associated with immune activation at morbid outcomes,including scarlet fever,endocarditis,meningitis,and rheumatic *** both stool and saliva,there is a pos-itive correlation between Streptococcus abundance and Sjogren’s syndrome(SS)and systemic lupus erythematosus(SLE).

关键词： lupus mother fever Streptococcus