214 research outputs found

    Layers of powers: societies and institutions in Europe

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    Historians and social scientists have offered many and varied definitions of the term “community”. This chapter focuses on specific examples of face-to-face or local communities in order to test the possibilities and limits of the two major analytical approaches to communities: an anthropological approach which identifies ‘community’ as an organic entity, and a symbolic one which considers feelings of belonging and self-identification as constitutive aspects of a community. In this quest, close attention is paid to the question of the stabilization of community’s structures through legislation and institutions, a process that integrates such micro-societies into broader networks of power, and renders them visible to historians. In the first section we examine what we have called a “world of communities”, from periods when communities constituted the dominant element of social structure. Examining ancient Jewish and medieval Icelandic communities, and then early modern Irish and Scottish clans, we try to identify their basic characteristics and to reconstruct the way they related to the rest of the social structure. The second section analyzes the emergence of new loyalties and models of social membership from the 19th century onwards, emphasizing how the discourse on communities played a crucial role in the construction of these diverse patterns of identification and differentiation. Finally, we explore the permanence of the communitarian world supposedly replaced by nationalism and other major modern ideologies along with the new meanings and uses of communities in the 20th and 21st centuries. In sum, this broad overview provides a preliminary narrative of the changes in the structures of communities and their shifting position within wider patterns of social organizations while drawing attention to parallel transformations in theoretical reflection on communities

    On the Observables Describing a Quantum Reference Frame

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    A reference frame F is described by the element g of the Poincare' group P which connects F with a given fixed frame F_0. If F is a quantum frame, defined by a physical object following the laws of quantum physics, the parameters of g have to be considered as quantum observables. However, these observables are not compatible and some of them, namely the coordinates of the origin of F, cannot be represented by self-adjoint operators. Both these difficulties can be overcome by considering a positive-operator-valued measure (POVM) on P, covariant with respect to the left translations of the group, namely a covariance system. We develop a construction procedure for this kind of mathematical structure. The formalism is also used to discuss the quantum observables measured with respect to a quantum reference frame.Comment: 23 pages, no figure

    Evaluating and Monitoring Energy Conservation in Multibuilding Clusters with Statistical Models

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    A standardized method for modeling energy consumption in mixed clusters of residential and commercial buildings is described. The basic approach is to delineate energy consumption along three dimensions: time, day-length, and temperature. The temperature-sensitive portion of energy consumption is captured by the Princeton Scorekeeping Method (PRISM). The time- and daylength-sensitive portions of energy consumption are captured by other variables. The models were designed to aid in determining the scope and performance of alternative financing activities on a U.S. Army base

    Energy Use Analysis for the Federal Energy Management Program

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    Recent congressional legislation allows federal agencies new authorities to contract for energy savings by sharing the acquired savings with an energy service company. As part of its charter to make the federal government more energy-efficient, the Federal Energy Management Program (FEMP) endeavors to improve the technical basis for such performance-based contracting. Specific tasks include the development of improved energy use baselining methods, refinement of a simplified energy analysis method and support to users, preparation of guidelines and procedures for energy savings initiatives, and publication of a manual to guide identification and analysis of energy conservation measures. This paper describes the current status and planned progress in each of these areas, and how these relate to several planned shared savings projects

    Use of Metering for Facility and Whole Building Energy Analysis by the U.S. Depratment of Energy Federal Energy Management Program

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    This paper details how the U.S. Department of Energy, Federal Energy Management Program (FEMP) is applying metering technology to conduct empirically based analyses o f energy use by federal agencies. Continuing developments in sensors, data acquisition systems, microcomputers and monitoring protocols are reducing the costs of metering to the point that it is becoming "too cheap not to meter" energy and the determinants of energy use at federal facilities . This has widespread consequence for FEMP if one accepts the axiom that "one can't manage what one doesn't measure." Several recently completed and ongoing activities being managed by Pacific Northwest laboratory for FEMP are highlighted in this paper. This includes the metering of energy end uses for a research laboratory building to support a shared energy savings contract, analysis of utility billing records, climate, and characteristics data for entire military bases to prioritize energy use testing requirements, and enhancements to simplified energy analysis tools to help federal energy decision-makers identify and evaluate cost-effective energy savings opportunities

    Medida da concentração plasmática do fator de crescimento do endotélio vascular em pacientes com câncer prostático: relação com estado clinico, gleason score, volume prostático e PSA sérico

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    OBJETIVO: Analisar os níveis circulantes do fator de crescimento do endotélio vascular em pacientes com câncer prostático comparados com uma população de indivíduos eutróficos. MÉTODOS: Vinte e seis indivíduos eutróficos e oitenta pacientes com câncer de próstata foram analisados nesse estudo. A coleta sangüínea foi realizada da mesma maneira em todos os pacientes e o plasma foi extraído para a determinação dos níveis do fator de crescimento do endotélio vascular, utilizando-se o método quantitativo ELISA (enzyme-linked immunosorbent assay). RESULTADOS: Os níveis de fator de crescimento do endotélio vascular plasmático encontraram-se significativamente elevados nos pacientes com doença metastática quando comparados com pacientes com doença localizada e com indivíduos sadios. Pacientes com PSA sérico maior que 20 ng/ml apresentaram níveis maiores de fator de crescimento do endotélio vascular plasmático quando comparados com pacientes com PSA menor que 20 ng/ml. Houve uma tendência dos pacientes com escore de Gleason de 8 a 10 apresentarem níveis maiores do fator de crescimento do endotélio vascular plasmático em relação a pacientes com escores de Gleason menores que 8. Não houve relação entre fator de crescimento do endotélio vascular plasmático e estado clínico, ou entre fator de crescimento do endotélio vascular e volume prostático em pacientes com câncer de próstata localizado. CONCLUSÃO: Os dados indicam que pacientes com câncer de próstata metastático apresentam níveis significativamente mais elevados de fator de crescimento do endotélio vascular plasmático quando comparados com pacientes com câncer localizado e com indivíduos normais.PURPOSE: This study focused on circulating levels of vascular endothelial growth factor in patients with prostate cancer compared to a normal population. METHODS: We analyzed 26 normal individuals and 80 patients with prostate cancer. Blood was drawn from all subjects, and plasma was extracted to determine the concentration of vascular endothelial growth factor using a quantitative immunoassay technique (ELISA-enzyme-linked immunosorbent assay). RESULTS: The median plasma level of vascular endothelial growth factor was significantly elevated in patients with metastatic disease compared to patients with localized disease and with healthy controls. Patients with serum prostate-specific antigen >; 20 ng/mL had significantly higher levels of plasma vascular endothelial growth factor than patients with serum prostate-specific antigen < 20 ng/mL. There was a trend for patients with a Gleason score of 8 to 10 to have higher levels of plasma vascular endothelial growth factor when compared to patients with lower Gleason scores. No relationship was found between plasma vascular endothelial growth factor and clinical staging, or between plasma vascular endothelial growth factor and prostate volume, in patients with localized prostate cancer. CONCLUSION: This study indicates that patients with metastatic prostate cancer have higher plasma vascular endothelial growth factor levels than patients with localized disease or in healthy controls

    Outcomes of flexible ureteroscopic lithotripsy with holmium laser for upper urinary tract calculi

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    OBJECTIVE: To assess the perioperative and financial outcomes of flexible ureteroscopic lithotripsy with holmium laser for upper tract calculi in 44 patients. MATERIALS AND METHODS: Between February 2004 and September 2006, 44 patients treated for upper tract stone with flexible ureteroscopic lithotripsy were evaluated. Renal stones were associated with collecting system obstruction in 15 (34%) patients, failed extracorporeal shock-wave lithotripsy (SWL) occurred in 14 (32%) patients, unilateral multiple stones in 18 (41%) patients, and multiple bilateral stones in 3 (7%). In 29 (66%) patients, the stone was located in the inferior calyx. Perioperative and financial outcomes were also evaluated. RESULTS: 50 procedures were performed in 44 patients. The mean stone burden on preoperative CT scan was 11.5 ± 5.8 mm. The mean operative time was 61.3 ± 29.4 min. The stone free rate was 93.1% after one procedure and 97.7% after a second procedure, with overall complication rate of 8%. Therapeutic success occurred in 92% and 93% of patients with lower pole stones and SWL failure, respectively. Treatment failure of a single session was associated with presence of a stone size larger than 15 mm (p = 0.007), but not associated with inferior calyx location (p = 0.09). Surgical disposables were responsible for 78% of overall costs. CONCLUSION: Flexible ureteroscopy using holmium laser is a safe and effective option for the treatment of upper urinary tract calculi. In addition, it can be considered an attractive option as salvage therapy after SWL failure or kidney calculi associated with ureteral stones. Stone size larger than 15 mm is associated with single session treatment failure

    Approximation of Feynman path integrals with non-smooth potentials

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    We study the convergence in L2L^2 of the time slicing approximation of Feynman path integrals under low regularity assumptions on the potential. Inspired by the custom in Physics and Chemistry, the approximate propagators considered here arise from a series expansion of the action. The results are ultimately based on function spaces, tools and strategies which are typical of Harmonic and Time-frequency analysis.Comment: 18 page

    Events in a Non-Commutative Space-Time

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    We treat the events determined by a quantum physical state in a noncommutative space-time, generalizing the analogous treatment in the usual Minkowski space-time based on positive-operator-valued measures (POVMs). We consider in detail the model proposed by Snyder in 1947 and calculate the POVMs defined on the real line that describe the measurement of a single coordinate. The approximate joint measurement of all the four space-time coordinates is described in terms of a generalized Wigner function (GWF). We derive lower bounds for the dispersion of the coordinate observables and discuss the covariance of the model under the Poincare' group. The unusual transformation law of the coordinates under space-time translations is interpreted as a failure of the absolute character of the concept of space-time coincidence. The model shows that a minimal length is compatible with Lorents covariance.Comment: 13 pages, revtex. Introductory part shortened and some arguments made more clea

    The Time-Energy Uncertainty Relation

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    The time energy uncertainty relation has been a controversial issue since the advent of quantum theory, with respect to appropriate formalisation, validity and possible meanings. A comprehensive account of the development of this subject up to the 1980s is provided by a combination of the reviews of Jammer (1974), Bauer and Mello (1978), and Busch (1990). More recent reviews are concerned with different specific aspects of the subject. The purpose of this chapter is to show that different types of time energy uncertainty relation can indeed be deduced in specific contexts, but that there is no unique universal relation that could stand on equal footing with the position-momentum uncertainty relation. To this end, we will survey the various formulations of a time energy uncertainty relation, with a brief assessment of their validity, and along the way we will indicate some new developments that emerged since the 1990s.Comment: 33 pages, Latex. This expanded version (prepared for the 2nd edition of "Time in quantum mechanics") contains minor corrections, new examples and pointers to some additional relevant literatur
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