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Distortions in focusing laser pulses due to spatio-temporal couplings:an analytic description

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High power Laser Science and Engineering 2024年第3期12卷 20-40页

作者： Klaus Steiniger Fabia Dietrich Daniel Albach Michael Bussmann Arie Irman Markus Loeser Richard pausch thomas püschel Roland Sauerbrey Susanne Schöbel Ulrich Schramm Mathias Siebold Karl Zeil Alexander Debus Helmholtz-Zentrum Dresden-Rossendorf DresdenGermany CASUS-Center for Advanced Systems Understanding GörlitzGermany Technische Universität Dresden DresdenGermany

In ultra-short laser pulses,small changes in dispersion properties before the final focusing mirror can lead to severe pulse distortions around the focus and therefore to very different pulse properties at the point of laser±matter interaction,yielding unexpected interaction *** mapping between far-and near-field laser properties intricately depends on the spatial and angular dispersion properties as well as the focal *** a focused Gaussian laser pulse under the influence of angular,spatial and group-delay dispersion,we derive analytical expressions for its pulse-front tilt,duration and width from a fully analytic expression for its electric field in the time±space domain obtained with scalar diffraction *** expression is not only valid in and near the focus but also along the entire propagation distance from the focusing mirror to the *** relating angular,spatial and group-delay dispersion before focusing at an off-axis parabola,where they are well measurable,to the respective values in the pulse’s focus are obtained by a ray tracing ***,these formulas are used to show in example setups that the pulse-front tilts of lasers with small initial dispersion can become several tens of degrees larger in the vicinity of the focus while being small directly in the *** formulas derived here provide the analytical foundation for observations previously made in numerical *** numerically simulating Gaussian pulse propagation and measuring properties of the pulse at distances several Rayleigh lengths off the focus,we verify the analytic expressions.

关键词： group-delay dispersion pulse-front tilt spatio-temporal couplings third-order dispersion ultra-short laser pulses

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Mutual Authentication protocols for RFID Systems

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International Journal of Automation and computing 2008年第4期5卷 348-365页

作者： Ashrar A.Omer Johnson p.thomas Department of Computer Science Oklahoma State University

With the availability of low-cost radio frequency identification (RFID) tags,security becomes an increasing concern. However,such tags do not permit complex cryptographic functions due to their computational,communications,and storage limitations. In this paper,we investigate the security issues and requirements of RFID systems,and propose ultra-light weight and light weight protocols for low-cost RFID *** proposed protocols has been applied to a supply chain management system.

关键词： Security mutual authentication supply chain management RFID Systems.

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Unusual presentations of eosinophilic gastroenteritis:Case series and review of literature

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World Journal of Gastroenterology 2009年第17期15卷 2156-2161页

作者： Rafiq A Sheikh thomas p prindiville R Erick pecha Boris H Ruebner Department of Gastroenterology Kaiser Permanente Medical Center 6600 Bruceville Road SacramentoCA 95823 United States Department of Gastroenterology University of California Davis 4150 V Street Sacramento CA95917 United States Department of Gastroenterology Marshall Medical Center 1100 Marshall Way Placerville CA 95667 United States Department of pathology University of California Davis 4150 V Street Sacramento CA 95917 United States

Eosinophilic gastroenteritis (EG) is an uncommon disease characterized by focal or diffuse eosinophilic infiltration of the gastrointestinal tract, and is usually associated with dyspepsia, diarrhea and peripheral eosinophilia. Diffuse gastrointestinal tract and colonic involvement are uncommon. The endoscopic appearance may vary from normal to mucosal nodularity and ulceration. Gastrointestinal obstruction is unusual and is associated with predominantly muscular disease. We present five unusual cases of EG associated with gastric outlet and duodenal obstruction. Two cases presented with acute pancreatitis and one had a history of pancreatitis. Four cases responded well to medical therapy and one had recurrent gastric outlet obstruction that required surgery. Four out of the five cases had endoscopic and histological evidence of esophagitis and two had colitis. Two patients had ascites. These cases reaffirm that EG is a disorder with protean manifestations and may involve the entire gastrointestinal tract. Gastric outlet and/or small bowel obstruction is an important though uncommon presentation of EG. It may also present as esophagitis, gastritis with polypoid lesions, ulcers or erosions, colitis and pancreatitis and may mimic malignancy.

关键词： Gastroenteritis Eosinophilic Gastrointestinal obstruction Eosinophilic esophagitis Eosinophilic colitis Eosinophilic pancreatitis

Iron-Catalysed C(sp^(2))-H Borylation with Expanded Functional Group Tolerance

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Chinese Journal of Chemistry 2022年第24期40卷 2875-2881页

作者： Luke Britton Jamie H.Docherty Gary S.Nichol Andrew p.Dominey Stephen p.thomas EaStCHEM School of Chemistry University of EdinburghEdinburghEH93FJ United Kingdom GSK Medicines Research Centre StevenageSG12NY United Kingdom

Arene C(sp^(2))-H bond borylation offers direct and efficient access to aryl boronic *** in situ catalyst activation and photoirradiation,the iron-catalysed C(sp^(2))-H borylation reaction of carboarenes,pyrroles,and indoles has been developed using only bench-stable pre-catalysts and *** functional group tolerance was observed including those not reported using previous methods(ArNH_(2),ArOH,ArSiR_(3),Arp(O)(O)_(2),ArC(O)NR_(2)).Mechanistic studies revealed iron-catalysed reductive deoxygenation,C—F protodefluorination,and a demethylation of aryl methyl ethers by C—O sigma bond hydroboration.

关键词： Iron Earth-abundant C-H borylation Boron photochemistry

OCEANOGRApHIC OBSERVATIONS DURING GALE

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Journal of Oceanology and Limnology 1987年第4期5卷 309-317页

作者： Larry p.Atkinson,thomas J.Berger Department of Oceanography Old Dominion University Norfolk VA 23508 U.S.A Department of Oceanography Old Dominion University Norfolk VA 23508 U.S.A

Results of oceanographic observations during GALE (Genesis of Atlantic Lows Experiment) are shown. The response of the thermohaline structure of the winds and cooling on the southeast U.S. shelf is described. The mean vertical heat flux over the shelf was calculated at certain stations. However, no attempt was made, in the absense of current meter data, to determine how much of the flux was due to advection or how much due to cooling or other causes.

关键词：卜工 OO IOp OCEANOGRApHIC OBSERVATIONS DURING GALE than Figure OVO OU

Content sensitivity based access control framework for Hadoop

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Digital Communications and Networks 2017年第4期3卷 213-225页

作者： Ashwin Kumar T.K. Hong Liu Johnson p. thomas Xiaofeh Hou Department of Computer Science Oklahoma State University Stillwater OK USA

Big data technologies have seen tremendous growth in recent years. They are widely used in both industry and academia. In spite of such exponential growth, these technologies lack adequate measures to protect data from misnse/abuse. Corporations that collect data from multiple sources are at risk of liabilities due to the exposure of sensitive information. In the current implementation of Hadoop, only file-level access control is feasible. providing users with the ability to access data based on the attlibutes in a dataset or the user＇s role is complicated because of the sheer volume and multiple formats （structured, unstructured and semi-structured） of data. In this paper, we propose an access control framework, which enforces access control policies dynamically based on the sensitivity of the data. This framework enforces access control policies by harnessing the data context, usage patterns and informat/on sensitivity. Information sensitivity changes over time with the addition and removal of datasets, which can lead to modifications in access control decisions. The proposed framework accommodates these changes. The proposed framework is automated to a large extent as the data itself determines the sensitivity with minimal user intervention. Our experimental results show that the proposed framework is capable of enforcing access control policies on non-multimedia datasets with minimal overhead.

关键词： Access control Data driven information sensitivity privacy Information value

Hepatic abscess associated with Salmonella serotype B in a chronic alcoholic patient

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Hepatobiliary & pancreatic Diseases International 2013年第4期12卷 440-442页

作者： Sidhartha S Tulachan Charles E Wilkins Anthony F Cutrona David Gemmel thomas p Marnejon Department of Internal Medicine St Elizabeth Health Center1044 Belmont AvenueYoungstown OH 44501 USA Department of Infectious Disease St Elizabeth Health Center1044 Belmont AvenueYoungstown OH 44501 USA Department of Research St Elizabeth Health Center1044 Belmont AvenueYoungstown OH 44501 USA

BACKGROUND: Hepatic abscess secondary to Salmonella is extremely rare in the United States and other Western countries. METHODS: A 43-year-old Caucasian man, with a history of chronic alcohol abuse, was admitted to the hospital for intermittent abdominal pain, fever and diarrhea. Clinical radiological and laboratory results were analyzed. Medical literature in pubMed pertaining to similar cases was reviewed. RESULTS: Stool culture was positive for Salmonella serotype B and a CT scan of the abdomen with contrast was consistent with a solitary hepatic abscess. Appropriate intravenous antibiotics followed by oral maintenance therapy for six weeks resulted in a complete clinical recovery and radiographic resolution. CONCLUSIONS: The cause of Salmonella hepatic abscess in our patient was most likely associated with decreased mucosal resistance to the bacteria, seeding of infection via transient portal bacteremia and loss of host immunity. Our case highlights the fact that appropriate antibiotic alone is sufficient in the management of a solitary hepatic abscess less than 3-5 cm.

关键词： hepatic abscess Salmonella alcoholic hypochlorhydria antibiotics

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IMpLEMENTATION OF MECHANISTIC CATTLE NUTRITION MODELS UNDER FIELD CONDITIONS

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IMPLEMENTATION OF MECHANISTIC CATTLE NUTRITION MODELS UNDER ...

Effect of Sr_(2) TiMnO_(6) fillers on mechanical, dielectric and thermal behaviour of pMMA polymer

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作者： thomas p Tylutki Agricultural Modeling and Training Systems LLC

Executive Summary Cattle nutrition models range in complexity from simple tabular systems (e.g.1984 Nutrient Requirements of Beef Cattle) to advanced mechanistic models (e.g. the Cornell Net Carbohydrate and protein System). As new research is published, these models continue to become more complex. Analogous to the increased level of complexity seen in cattle nutrition models is the evolution of computer power. In 1989, the Intel 486 processor was state of the art and users were accustomed to the MS-DOS operating system. Also in this year, the National Research Council

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Journal of Advanced Dielectrics 2015年第3期5卷 1-11页

作者： p.thomas B.S.Dakshayini H.S.Kushwaha Rahul Vaish Dielectric Materials Division Central Power Research Institute BangaloreKarnataka 560080India Aerospace Engineering Indian Institute of Science BangaloreKarnataka 560012India School of Engineering Indian Institute of Technology Mandi Himachal Pradesh 175001India

Composites of poly(methyl methacrylate)(pMMA)and Sr_(2) TiMnO_(6)(STMO)were fabricated via melt mixing followed by hot pressing *** were characterized using X-ray diffraction(XRD),thermo gravimetric analysis(TGA),differential scanning calorimetry(DSC),thermo mechanical analysis(TMA)and impedance analyser for their structural,thermal and dielectric *** coefficient of thermal expansion(CTE)was measured between 40℃ and 100℃ for pure pMMA is 115.2ppm/℃,which was decreased to 78.58ppm/℃ when the STMO content was increased to 50 wt.%in *** was no difference in the glass transition(T g)temperature of the pMMA polymer and their ***,the FTIR analysis indicated possible interaction between the pMMA and *** density and the hardness were increased as the STMO content increased in the pMMA *** was found to be as high as 30.9 at 100Hz for the pMMAþSTMO-50 wt.%composites,indicating the possibility of using these materials for capacitor *** thermal stability of polymer was enhanced by incorporation of STMO fillers.

关键词： polymer composite dielectric properties mechanical properties thermal properties