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An experimental study of elastic properties of dragonfly-like flapping wings for use in biomimetic micro air vehicles(BMAVs)

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Chinese Journal of Aeronautics 2017年第2期30卷 726-737页

作者： Praveena Nair Sivasankaran thomas arthur ward Erfan Salami Rubentheren Viyapuri Christopher J.Fearday Mohd Rafie Johan Department of Mechanical Engineering University of Malaya KuaIa Lumpur 50603 Malaysia School of Engineering and Physical Sciences Heriot-Watt University Malaysia Putrajaya 62200 Malaysia Department of Electrical Engineering University of Malaya Kuala Lumpur 50603 Malaysia

This article studies the elastic properties of several biomimetic micro air vehicle（BMAV）wings that are based on a dragonfly *** are a new class of unmanned micro-sized air vehicles that mimic the flapping wing motion of flying biological organisms（e.g.,insects,birds,and bats）.Three structurally identical wings were fabricated using different materials：acrylonitrile butadiene styrene（ABS）,polylactic acid（PLA）,and *** wing frame structures were fabricated from these materials and then a nanocomposite film was adhered to them which mimics the membrane of an actual *** wings were then attached to an electromagnetic actuator and passively flapped at frequencies of 10-250 Hz.A three-dimensional high frame rate imaging system was used to capture the flapping motions of these wings at a resolution of 320 pixels x 240 pixels and 35000 frames per *** maximum bending angle,maximum wing tip deflection,maximum wing tip twist angle,and wing tip twist speed of each wing were measured and compared to each other and the actual dragonfly *** results show that the ABS wing has considerable flexibility in the chordwise direction,whereas the PLA and acrylic wings show better conformity to an actual dragonfly wing in the spanwise *** studies have shown that the aerodynamic performance of a BMAV flapping wing is enhanced if its chordwise flexibility is increased and its spanwise flexibility is ***,the ABS wing（fabricated using a 3D printer） shows the most promising results for future applications.

关键词： ABS Acrylic Biomimetic micro air vehicle Flapping mechanism PLA Wing structure

JAMES GLIMM:MATHEMATICIAN,FRIEND,MENTOR

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Acta Mathematica Scientia 2010年第2期30卷 369-376页

作者： arthur Jaffe thomas Spencer Department of Mathematics Harvard University School of Mathematics Institute for Advanced Study

A description of Jim＇s contributions to mathematics would take us far beyond our expertise. Jim was never content to spend too long in any one area of mathematics. Operator algebras, hyperbolic systems of conservation laws, fluid dynamics, quantum field theory and statistical mechanics and the computational aspects of applied mathematics are just a few of the areas to which Jim has contributed. Here we relate a few impressionistic recollections of personal interactions, together with some ideas about his work in quantum field theory and statistical mechanics. In spite of the non-technical character of these observations, we hope nevertheless that they will provide pleasure for our dear friend and for other readers as well.

关键词： JAMES GLIMM work

High Oxygen Nanocomposite Barrier Films Based on Xylan and Nanocrystalline Cellulose

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Nano-Micro Letters 2010年第4期2卷 235-241页

作者： Amit Saxena thomas J.Elder Jeffrey Kenvin arthur J.Ragauskas School of Chemistry and Biochemistry Georgia Institute of Technology USDA-Forest Service Southern Research Station Micromeritics Instrument Corporation

The goal of this work is to produce nanocomposite film with low oxygen permeability by casting an aqueous solution containing xylan,sorbitol and nanocrystalline *** morphology of the resulting nanocomposite films was examined by scanning electron microscopy and atomic force microscopy which showed that control films containing xylan and sorbitol had a more open structure as compared to xylan-sorbitol films containing sulfonated nanocrystalline *** average pore diameter,bulk density,porosity and tortuosity factor measurements of control xylan films and nanocomposite xylan films were examined by mercury intrusion porosimetry *** films reinforced with nanocrystalline cellulose were denser and exhibited higher tortuosity factor than the control xylan *** xylan films had average pore diameter,bulk density,porosity and tortuosity factor of 0.1730 μm,0.6165 g/ml,53.0161% and 1.258,respectively as compared to xylan films reinforced with 50% nanocrystalline cellulose with average pore diameter of 0.0581 μm,bulk density of 1.1513 g/ml,porosity of 22.8906% and tortuosity factor of *** transmission rate tests demonstrated that films prepared with xylan,sorbitol and 5%,10%,25% and 50% sulfonated nanocrystalline cellulose exhibited a significantly reduced oxygen permeability of 1.1387,1.0933,0.8986 and 0.1799 cm^3×μm/m^2×d×k Pa respectively with respect to films prepared solely from xylan and sorbitol with a oxygen permeability of 189.1665 cm^3×μm/m^2×d×k *** properties suggested these nanocomposite films have promising barrier properties.

关键词： Nanocomposites Xylan Nanocrystalline cellulose Oxygen barrier

Intrahepatic Cholangiocarcinoma and Hepatocellular Carcinoma:Real-life Data on Liver Disease,Treatment and Prognosis

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Journal of Clinical and Translational Hepatology 2023年第5期11卷 1106-1117页

作者： Xavier Adhoute Olivia Pietri Guillaume Pénaranda thomas Wolf Patrick Beaurain Olivier Monnet arthur Laquière Justine Bonomini Frédéric Neumann Olivier Levrel Jean-Pascal Buono Xavier Hanna Paul Castellani HervéPerrier Marc Bourliere Rodolphe Anty Department of Gastroenterology and Hepatology Hôpital Saint-JosephMarseilleFrance Department of Biostatistics AlphaBio-Biogroup LaboratoryMarseilleFrance Department of Radiology Hôpital Saint-JosephMarseilleFrance Department of Clinical Research Hôpital Saint-JosephMarseilleFrance Medipath EguillesFrance Department of Hepatobiliary Surgery Hôpital Saint-JosephMarseilleFrance Department of Gastroenterology and Hepatology Hôpital Universitaire de l’ArchetNiceFrance

Background and Aims:Hepatocellular carcinoma(HCC)and intrahepatic cholangiocarcinoma(iCCA)have common features and *** real-life study investigated their characteristics,treatment modalities,and ***:This retrospective comparative study was performed in 1,075 patients seen at one tertiary center between January 2008 and December *** survival(OS)was estimated by the Kaplan-Meier *** of iCCAs after histological and radiological review,and molecular profiling was ***:HCCs patients were more likely to have early-stage disease than iCCA *** patients were more likely to be female,especially those patients without cirrhosis(43%vs.17%).Cirrhosis was prominent among HCC patients(89%vs.34%),but no difference in underlying liver disease among cirrhotic patients was *** of HCC patients was 18.4(95%CI:6.4,48.3)months,that of iCCA patients was 7.0(95%CI:3.4,20.1)*** of Barcelona Clinic Liver Cancer C HCC patients was 7.8(95%CI:4.3,14.2)months,that of advanced/metastatic iCCA patients was 8.5(95%CI:5.7,12.3)*** patients treated with sorafenib,OS was longer in HCC patients who received subsequent tyrosine kinase inhibitor *** significant OS difference was found between iCCA patients with and without cirrhosis or according to histological subtype.A targetable molecular alteration was detected in 50%of the iCCA ***:In this French series,cirrhosis was common in iCCA,which showed etiological factors comparable to those of HCC,implying a distinct oncogenic *** entities had a dismal prognosis at advanced ***,systemic therapies sequencing in HCC and molecular profiling in iCCA offer new insights.

关键词： Intrahepatic cholangiocarcinoma Hepatocellular carcinoma Cirrhosis NASH Oncogenic alterations

The beginnings of plasmomechanics： towards plasmonic strain sensors

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Frontiers of Materials Science 2015年第2期9卷 170-177页

作者： thomas MAURER Joseph MARAE-DJOUDA Ugo CATALDI arthur GONTIER Guillaume MONTAY Yazid MADI Benoit PANICAUD Demetrio MACIAS Pierre-Michel ADAM Gaetan LEVEQUE thomas BURGI Roberto CAPUTO Laboratory of Nanotechnology and Instrumentation in Optics (LNIO) ICD CNRS UMR 6281 University of Technology of Troyes CS 42060 10004 Troyes France The Laboratory of Mechanical Systems and Concurrent Engineeringl ICD CNRS UMR 6281 University of Technology of Troyes CS 42060 10004 Troyes France Ermess EPF Sceaux France Center of Materials Mines ParisTech UMR CNRS 7633 BP 87 91003 Evry Cedex France Institute of Electronics Microelectronics and Nanotechnology (IEMN CNRS-8520) Cite Scientifique Avenue Poincare 59652 Villeneuve d'Ascq France Department of Physical Chemistry University of Geneva 30 Quai Ernest-Ansermet 1211 Geneva 4 Switzerland Department of Physics and CNR-NANOTEC University of Calabria 87036 Rende Italy

This article exposes the beginnings of a new field which could be named as ＂plasmomechanics＂. Plasmomechanics comes from the convergence between mechanics and plasmonics. Here we discuss a relatively recent topic whose technolo- gical aim is the development of plasmonic strain sensors, The idea is based on the ability to deduce Au nanoparticles （NPs） distance distributions from polarized optical extinction spectroscopy which could thus give access to material strains. Variations of interparticle distances distributions can indeed lead to variations of plasmonic coupling and thus to material color change as shown here experimentally and numerically for random Au NP assemblies deposited onto elastomer films,

关键词： localized surface plasmon resonance (LSPR) metallic nanoparticle strain composite material elastomeric film

Establishing Benchmarks for Helicopter EMS Patient Stabilization Times in Interfacility Transport for Primary Percutaneous Coronary Intervention

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International Journal of Clinical Medicine 2012年第7期3卷 765-768页

作者： Loren Brown Annette arthur Claudia Keeling Christine Yuhas Stephen H. thomas Air Evac Lifeteam Oklahoma West Plains USA

Helicopter EMS (HEMS) allows for patients to be quickly transported into regional cardiac centers, often to receive primary percutaneous coronary intervention (PCI). Since PCI is a time-critical therapy, it is important that patients get to primary PCI as quickly as possible. HEMS crews’ “on-scene” times for trauma patients have been extensively studied, and recent years have seen many efforts to minimize the time required to prepare patients for transport. There has been less attention to interfacility transport “scene times” for HEMS crews at referring hospitals;this includes stabilization times for preparing cardiac patients for loading onto aircraft for HEMS transport to primary PCI. In the absence of guiding evidence, system benchmarking and quality improvement are difficult. Therefore the current study was undertaken, to assess and describe the HEMS crew “on-scene” times or “patient stabilization times” (PSTs) at referring hospitals, for interfacility transported cardiac patients flown for primary PCI. Descriptive analysis identified a PST median of 19 minutes (interquartile range 15 - 24), and univariate analyses using Kruskal-Wallis testing found no association between prolonged PST and sending unit type (Emergency Department versus other), off-hours transports, or relatively frequent (at least monthly) use of HEMS (p for all comparisons > 0.64). Outlier PSTs, defined a priori as those exceeding the median by at least a half-hour, were found in 12% of all cases. These data could be useful as a starting point for system planning and benchmarking efforts in regionalized systems of acute cardiac care.

关键词： Helicopter EMS Percutaneous Coronary Intervention Regional Cardiac Care Benchmarking

Towards Enhanced Program Comprehension for Service Oriented Architecture (SOA) Systems

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Journal of Software Engineering and Applications 2013年第9期6卷 435-445页

作者： Eman El-Sheikh thomas Reichherzer Laura White Norman Wilde John Coffey Sikha Bagui George Goehring arthur Baskin Department of Computer Science University of West Florida Pensacola USA Intelligent Information Technologies Corporation Indianapolis USA

Service Oriented Architecture (SOA) is an emerging paradigm for orchestrating software components to build new composite applications that enable businesses, government agencies and other organizations to collaborate across institutional boundaries. SOA offers new languages and a variety of software development tools that enable software engineers to configure software as services and to interconnect services with other services independent of differences in operating platform and programming and communicating languages. However, SOA composite applications introduce additional complexity into the construction, deployment and maintenance of software, for the purpose of aggravating the issue of program comprehension, which is at the heart of software maintenance. This article describes the challenges in SOA program comprehension and reports on the results of a two-part case study aimed at identifying information that would help a SOA software maintainer. Analysis of the results indicates a need for higher-level abstractions and visualizations that can enhance conventional text-based search to support SOA program understanding. This paper then reports on several specific abstractions, visualization methods, and the development of an intelligent search tool to enhance comprehension of the relationships and data within a SOA composite application.

关键词： Service Oriented Architecture Software Maintenance Program Comprehension Intelligent Search Abstraction Visualization Web Services

Resistance Measured by Airflow Perturbation Compared with Standard Pulmonary Function Measures

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Open Journal of Respiratory Diseases 2013年第2期3卷 63-67页

作者： Tania Haque Jafar Vossoughi arthur T. Johnson Wanda Bell-Farrell thomas Fitzgerald Steven M. Scharf Engineering and Scientific Research Associates Olney USA Fischell Department of Bioengineering University of Maryland College Park USA University of Maryland Baltimore USA

Background: Routine lung function testing requires expensive equipment, or requires maximum expiratory effort. The airflow perturbation device (APD) is a light handheld device, allowing for serial measures of respiratory resistance noninvasively and effortlessly. Methods: In a convenience sample of 398 patients undergoing pulmonary function testing, we compared routine spirometric indices (forced expired volume in 1 second (FEV1), peak expiratory flow (PEF)), and airways resistance (Raw-272 patients), to measures of respiratory resistance measured with the APD including inspiratory (IR), expiratory (ER) and averaged (AR) resistance. Results: Measures of lung function were significantly correlated (p 0.001). On regression analysis, between 7% - 17% of the variance (R2) for FEV1, PEF, and Raw was explained by APD measurements. Approximately 2/3 of the variance in FEV1 was explained by PEF measurements. Conclusions: APD measurements of lung function correlate with conventional measures. Future studies should be directed at exploring the use of the APD device in serial measures of lung function in patients with lung disease.

关键词： Airflow Perturbation Device Pulmonary Function Forced Expired Volume in 1 Second Peak Expiratory Flow Airway Resistance

Evidence for the presence of GPRC6A in the rat mesenteric artery

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Evidence for the presence of GPRC6A in the rat mesenteric ar...