982 resultados para Shneur Zalman, of Lyady, 1745-1813
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The curing temperature, pressure, and curing time have significant influence on finished thermosetting composite products. The time of pressure application is one of the most important processing parameters in the manufacture of a thermosetting composite. The determination of the time of pressure application relies on analysis of the viscosity variation of the polymer, associated with curing temperature and curing time. To determine it, the influence of the time of pressure application on the physical properties of epoxy-terminated poly(phenylene ether ketone) (E-PEK)-based continuous carbon fiber composite was studied. It was found that a stepwise temperature cure cycle is more suitable for manufacture of this composite. There are two viscosity valleys, in the case of the E-PEK system, associated with temperature during a stepwise cure cycle. The analysis on the effects of reinforcement fraction and defect content on the composite sheet quality indicates that the width-adjustable second viscosity valley provides a suitable pressing window. The viscosity, ranging from 400 to 1200 Pa . s at the second viscosity valley, is the optimal viscosity range for applying pressure to ensure appropriate resin flow during curing process, which enables one to get a finished composite with optimal fiber volume fraction and low void content. (C) 1997 John Wiley & Sons, Inc.
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Based on the Navier-Stokes equation, an equation describing the Langmuir circulation is derived by a perturbation method when the influences of Coriolis force and buoyancy force are both considered. The approach used in the analysis is similar to the works carried out by Craik and Leibovich [J. Fluid Mech. 73 (1976) 401], Leibovich [J. Fluid Mech. 79 (1977) 715] and Huang [J. Fluid Mech. 91 (1979) 191]. Potential applications of the equation proposed are discussed in the area of Antarctic circumpolar current.
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To investigate the effects of body size and water temperature on feeding and growth in the sea cucumber Apostichopus japonicus (Selenka), the maximum rate of food consumption in terms of energy (C-maxe; J day(-1)) and the specific growth rate in terms of energy (SGRe; % day(-1)) in animals of three body sizes (mean +/- SE) - large (134.0 +/- 3.5 g), medium (73.6 +/- 2.2 g) and small (36.5 +/- 1.2 g) - were determined at water temperatures of 10, 15, 20, 25 and 30 degrees C. Maximum rate of food consumption in terms of energy increased and SGRe decreased with increasing body weight at 10, 15 and 20 degrees C. This trend, however, was not apparent at 25 and 30 degrees C, which could be influenced by aestivation. High water temperatures (above 20 degrees C) were disadvantageous to feeding and growth of this animal; SGRe of A. japonicus during aestivation was negative. The optimum temperatures for food consumption and for growth were similar and were between 14 and 15 degrees C, and body size seemed to have a slight effect on the optimal temperature for food consumption or growth. Because aestivation of A. japonicus was temperature dependent, the present paper also documented the threshold temperatures to aestivation as indicated by feeding cessation. Deduced from daily food consumption of individuals, the threshold temperature to aestivation for large and medium animals (73.3-139.3 g) was 24.5-25.5 degrees C, while that for small animals (28.9-40.7 g) was between 25.5 and 30.5 degrees C. These values are higher than previous reports; differences in sign of aestivation, experimental condition and dwelling district of test animals could be the reasons.
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Background Good blood pressure (BP) control reduces the risk of recurrence of stroke/transient ischaemic attack (TIA). Although there is strong evidence that BP telemonitoring helps achieve good control, none of the major trials have considered the effectiveness in stroke/TIA survivors. We therefore conducted a feasibility study for a trial of BP telemonitoring for stroke/ TIA survivors with uncontrolled BP in primary care. Method Phase 1 was a pilot trial involving 55 patients stratified by stroke/TIA randomised 3:1 to BP telemonitoring for 6 months or usual care. Phase 2 was a qualitative evaluation and comprised semi-structured interviews with 16 trial participants who received telemonitoring and 3 focus groups with 23 members of stroke support groups and 7 carers. Results Overall, 125 patients (60 stroke patients, 65 TIA patients) were approached and 55 (44%) patients were randomised including 27 stroke patients and 28 TIA patients. Fifty-two participants (95%) attended the 6-month follow-up appointment, but one declined the second daytime ambulatory blood pressure monitoring (ABPM) measurement resulting in a 93% completion rate for ABPM − the proposed primary outcome measure for a full trial. Adherence to telemonitoring was good; of the 40 participants who were telemonitoring, 38 continued to provide readings throughout the 6 months. There was a mean reduction of 10.1 mmHg in systolic ABPM in the telemonitoring group compared with 3.8 mmHg in the control group, which suggested the potential for a substantial effect from telemonitoring. Our qualitative analysis found that many stroke patients were concerned about their BP and telemonitoring increased their engagement, was easy, convenient and reassuring Conclusions A full-scale trial is feasible, likely to recruit well and have good rates of compliance and follow-up.
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The TCP/IP architecture was originally designed without taking security measures into consideration. Over the years, it has been subjected to many attacks, which has led to many patches to counter them. Our investigations into the fundamental principles of networking have shown that carefully following an abstract model of Interprocess Communication (IPC) addresses many problems [1]. Guided by this IPC principle, we designed a clean-slate Recursive INternet Architecture (RINA) [2]. In this paper, we show how, without the aid of cryptographic techniques, the bare-bones architecture of RINA can resist most of the security attacks faced by TCP/IP. We also show how hard it is for an intruder to compromise RINA. Then, we show how RINA inherently supports security policies in a more manageable, on-demand basis, in contrast to the rigid, piecemeal approach of TCP/IP.
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The dissertation proposes that one of the more fruitful ways of interpreting Burke's work is to evaluate him as an oral performer rather than a literary practitioner and it argues that in his voice can be heard the modulations of the genres and conventions of oral composition of eighteenth-century Gaelic Ireland. The first chapter situates Burke in the milieu of the Gaelic landed class of eighteenth-century Ireland. The next chapter examines how the rich oral culture of the Munster Gaelic gentry, where Burke spent his childhood days, was to provide a lasting influence on the form and content of Burke's work. His speeches on the British constitution are read in the context of the historical and literary culture of the Jacobites, specifically the speculum principis, Párliament na mBán. The third chapter surveys the tradition of Anglo-Irish theoretical writings on oratory and discusses how Burke is aligned with this school. The focus is on how Burke's thought and practice, his 'idioms', might be understood as being mediated through the criterion of orality rather than literature. The remaining chapters discuss Burke's politics and performance in the light of Gaelic cultural practices such as the rituals of the courts of poetry, the Warrant Poems or Barántas; the performance of funeral laments and elegies, Caoineadh, the laments for the fallen nobility, Marbhna na daoine uaisle, the satires and the political vision allegories of Munster, Aislingí na Mumhan; to show how they provide us with a remarkable context for discussing Burke's poetical-political performance. In hearing Burke's voice through the body of Gaelic culture our understanding of Burke's position in the wider world of the eighteenth century (and hence his meaning) is profoundly affected.
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A growing number of software development projects successfully exhibit a mix of agile and traditional software development methodologies. Many of these mixed methodologies are organization specific and tailored to a specific project. Our objective in this research-in-progress paper is to develop an artifact that can guide the development of such a mixed methodology. Using control theory, we design a process model that provides theoretical guidance to build a portfolio of controls that can support the development of a mixed methodology for software development. Controls, embedded in methods, provide a generalizable and adaptable framework for project managers to develop their mixed methodology specific to the demands of the project. A research methodology is proposed to test the model. Finally, future directions and contributions are discussed.
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BACKGROUND: Many patients with diabetes have poor blood pressure (BP) control. Pharmacological therapy is the cornerstone of effective BP treatment, yet there are high rates both of poor medication adherence and failure to intensify medications. Successful medication management requires an effective partnership between providers who initiate and increase doses of effective medications and patients who adhere to the regimen. METHODS: In this cluster-randomized controlled effectiveness study, primary care teams within sites were randomized to a program led by a clinical pharmacist trained in motivational interviewing-based behavioral counseling approaches and authorized to make BP medication changes or to usual care. This study involved the collection of data during a 14-month intervention period in three Department of Veterans Affairs facilities and two Kaiser Permanente Northern California facilities. The clinical pharmacist was supported by clinical information systems that enabled proactive identification of, and outreach to, eligible patients identified on the basis of poor BP control and either medication refill gaps or lack of recent medication intensification. The primary outcome is the relative change in systolic blood pressure (SBP) measurements over time. Secondary outcomes are changes in Hemoglobin A1c, low-density lipoprotein cholesterol (LDL), medication adherence determined from pharmacy refill data, and medication intensification rates. DISCUSSION: Integration of the three intervention elements--proactive identification, adherence counseling and medication intensification--is essential to achieve optimal levels of control for high-risk patients. Testing the effectiveness of this intervention at the team level allows us to study the program as it would typically be implemented within a clinic setting, including how it integrates with other elements of care. TRIAL REGISTRATION: The ClinicalTrials.gov registration number is NCT00495794.
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Behavior, neuropsychology, and neuroimaging suggest that episodic memories are constructed from interactions among the following basic systems: vision, audition, olfaction, other senses, spatial imagery, language, emotion, narrative, motor output, explicit memory, and search and retrieval. Each system has its own well-documented functions, neural substrates, processes, structures, and kinds of schemata. However, the systems have not been considered as interacting components of episodic memory, as is proposed here. Autobiographical memory and oral traditions are used to demonstrate the usefulness of the basic-systems model in accounting for existing data and predicting novel findings, and to argue that the model, or one similar to it, is the only way to understand episodic memory for complex stimuli routinely encountered outside the laboratory.
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A relatively unexplored area of the harpsichord repertoire is the group of transcriptions made by J.S. Bach (1685-1750), Jean Henry d'Anglebert (1629-1691), and Jean-Baptiste Forqueray (1699-1782). These transcriptions are valuable and worth exploring and performing. Studying them provides unique insights into their composer‘s musical thinking. By comparing transcriptions with their original sources, the transcriber's decisions and priorities can be observed. The performance component of this dissertation comprises three recitals. The first features works of Johann Sebastian Bach: two transcriptions of violin concerti by Antonio Vivaldi (1678-1741), and two transcriptions of trio sonatas by Johann Adam Reinken (1643-1722). The most salient feature of Bach‘s transcriptions is his addition of musical material: ornamenting slow movements, adding diminutions and idiomatic keyboard figurations throughout, and recomposing and expanding fugal movements. The second recital features works of Jean Henry d'Anglebert and Jean-Baptiste Forqueray, two French composer/performers. From d'Anglebert‘s many transcriptions, I assembled two key-related suites: the first comprised of lute pieces by Ennemond Gaultier (c. 1575-1651), and the second comprised of movements from operas by Jean-Baptiste Lully (1632-1687). Forqueray's transcriptions are of suites for viola da gamba and continuo, composed by his father, Antoine Forqueray (1671-1745). Creative and varied ornamentation, along with the style brisé of arpeggiated chords, are the most important features of d‘Anglebert‘s transcriptions. Forqueray‘s transcriptions are highly virtuosic and often feature the tenor and bass range of the harpsichord. The third recital features my own transcriptions: the first suite for solo cello by J.S. Bach, excerpts from the opera La Descente d’Orphée aux Enfers by Marc-Antoine Charpentier (1643-1704), and two violin pieces by Nicola Matteis (fl. c. 1670-c. 1698). In these transcriptions, I demonstrate what I have learned from studying and performing the works in the first two recitals. These recitals were performed in the Leah Smith Hall at the University of Maryland on May 4, 2010; May 11, 2010; and October 7, 2010. They were recorded on compact discs and are archived within the Digital Repository at the University of Maryland (DRUM).
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Artificial neural network (ANN) models for water loss (WL) and solid gain (SG) were evaluated as potential alternative to multiple linear regression (MLR) for osmotic dehydration of apple, banana and potato. The radial basis function (RBF) network with a Gaussian function was used in this study. The RBF employed the orthogonal least square learning method. When predictions of experimental data from MLR and ANN were compared, an agreement was found for ANN models than MLR models for SG than WL. The regression coefficient for determination (R2) for SG in MLR models was 0.31, and for ANN was 0.91. The R2 in MLR for WL was 0.89, whereas ANN was 0.84.Osmotic dehydration experiments found that the amount of WL and SG occurred in the following descending order: Golden Delicious apple > Cox apple > potato > banana. The effect of temperature and concentration of osmotic solution on WL and SG of the plant materials followed a descending order as: 55 > 40 > 32.2C and 70 > 60 > 50 > 40%, respectively.
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The purpose of this report is to give an overview of plankton ecology in the North Sea, and the processes that effect it, as derived from current research. The Sir Alister Hardy Foundation has extensive data for the North Sea area, and other sources have also been used to provide information for this report. Shortfalls in current research have also been highlighted. The information contained herein is to be contributed towards an information base for the Strategic Environmental Assessment. The North Sea is an extension of the North Atlantic that has an area of 574,980 km2. The deepest area is off the coast of Norway (660m), with a number of shallow areas, such as the Dogger Bank (15m). The North Sea represents a large source of hydrocarbons that have been exploited since the early 1970s. The aim of this study is to provide the Department of Trade and Industry with biological data on the planktonic community of the North Sea, as a contribution towards the Strategic Environmental Assessment (SEA 2). An overview of phyto- and zoo- plankton community composition, plankton blooms, Calanus, mero-, pico- and megaplankton, sensitivity to disturbance / contamination, phytodetritus and vertical fluxes and the resting stages of phytoplankton is made using the results of the survey database. Additional published literature has also been used, and gaps in available data have been highlighted. 1.3 The Continuous Plankton Recorder (CPR) survey provides a unique long-term dataset of plankton abundance in the North Atlantic and North Sea (Warner and Hays 1994). The survey has been running for almost 70 years, using ‘ships of opportunity’ to tow CPRs on regular, and incidental routes, sampling at a depth of 10 m. Each sample represents 18 km of tow and approximately 3 m3 of filtered seawater. Over 400 taxa of plankton are routinely identified by a team of taxonomists. The samples are also compared to colour charts to give an indication of ‘greenness’, which provides a visual index of chlorophyll value. CPRs have been towed for over 4 million nautical miles, accumulating almost 200,000 samples. The design of the CPR has remained virtually unchanged since sampling started, thus providing a consistency of sampling that provides good historical comparisons. By systematically monitoring the plankton over a period, changes in abundance and long term trends can be distinguished. From this baseline data, inferences can be made, particularly concerning climate change and potentialanthropogenic impacts.
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In this paper we present a couple of sheets of Umbelliferae that are preserved in the RCAXII herbaria. One of them, Selinum carvifolia, where collected in the Gredos Mountains by Miguel Barnades Mainader and was identified by his son Miguel Barnades Clarís. The other, Tragium flabellifolium, was collected in Mieres (Asturias) by Esteban de Prado and identified by Mariano La Gasca.