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311.
In 1987, the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) initiated the Agenda for Change, a major revision in the evaluation process for hospitals. An essential component of that change was to shift the emphasis away from standards for individual departments to standards for hospital-wide functions. In recent years, hospital librarians have focused their energy and attention on complying with the standards for the "Management of Information" chapter, specifically the IM.9 section on knowledge-based information. However, the JCAHO has listed the health sciences librarian and library services as having responsibilities in six other chapters within the Comprehensive Accreditation Manual for Hospitals. These chapters can have a major impact on the services of the hospital library for two reasons: (1) they are being read by hospital leaders and other professionals in the organization, and (2) they articulate specific ways to apply knowledge-based information services to the major functions within the hospital. These chapters are "Education"; "Improving Organizational Performance"; "Leadership"; "Management of Human Resources"; "Management of the Environment of Care"; and "Surveillance, Prevention, and Control of Infection." The standards that these chapters promote present specific opportunities for hospital librarians to apply knowledge-based information resources and service to hospital-wide functions. This article reviews these chapters and discusses the standards that relate to knowledge-based information.  相似文献   
312.
The case of a patient with a false-positive fracture on the panoramic view of the mandible is presented. The patient motion produced a spurious image that perfectly mimicked a fracture without any evidence of motion. To better assess motion artifact, panoramic views of a "phantom" human skull were developed with movement during the exposure. These radiographs were analyzed with the assistance of a radiologist, and diagnostic features of motion artifact are discussed. Some radiographs were created by movement that mimicked fractures without the telltale signs of motion artifact. These "motion pseudofractures" are diagnosed clinically if the examiner knows that motion can mimic fractures, and all x-ray findings are carefully correlated with clinical findings. Diagnosis of a motion pseudofracture will avoid the additional expense and time of a specialty consultation.  相似文献   
313.
As the new millennium approaches, research into the genetic aspects of schizophrenia has already made an impressive start toward an integrated model which is discovering roles for genetic agents, environmental agents and experiences, and chance factors. The best model follows that proposed for understanding such complex diseases as coronary artery disease and diabetes. Genetic information has come from both genetic epidemiology and molecular genetics. Evidence for gene regions on 6p and 8p gives the strongest support for harboring schizophrenia susceptibility genes, based on international collaborative studies that "generally" replicate one another; evidence for regions on 3p, 5q, 9p, 20p, and 22q, while less compelling, will encourage focused work. Determining the steps between the regions and the phenotype will challenge the next generation of scientists.  相似文献   
314.
The paper points out two methods of research in the field of psychosomatic resp. psychooncologic research. The "traditional method" of an Inter-Group-Comparison is confronted with the "modificated method" of an Intra-Group-Comparison. The methodological advantage of taxonomic subgroups is demonstrated at a population of 60 breast cancer patients. Two homogeneous subgroups of the investigated population can be distinguished not only by contents criteria but also by means of a cluster-analysis. The prognostic importance of the psychodynamic profile within the different subgroups is discussed. In this context defense mechanisms are particularly relevant.  相似文献   
315.
Shaping self-similar traffic at access of optical network   总被引:1,自引:0,他引:1  
Halima  Tijani  Tülin  Grard 《Performance Evaluation》2003,53(3-4):187-208
The focus of this paper is shaping of self-similar traffic at the access of an optical node. Due to the lack of optical memories, we suggest a combined exploitation of electronic memories in the edge of the optical network by means of shaping and propose two novel shaping algorithms that dynamically shape the incoming traffic so as to meet Quality of Service (QoS) requirements while keeping with the optical core network constraints. The first algorithm follows a deterministic approach and is based on the service curves theory. It dynamically, on an interval basis, adjusts the shaping parameters to the token bucket described self-similar traffic. The second, alternative shaping algorithm follows a stochastic approach. It blindly shapes the traffic using a jumping observation window.  相似文献   
316.
Electron transfer between bases in double helical DNA   总被引:1,自引:0,他引:1  
Fluorescent analogs of adenine that selectively oxidize guanine were used to investigate photoinduced electron transfer through the DNA pi-stack as a function of reactant stacking and energetics. Small variations in these factors led to profound changes in the kinetics and distance dependences of DNA-mediated electron-transfer reactions. Values of beta, a parameter reflecting the dependence of electron transfer on distance, ranged from 0.1 to 1.0 per angstrom. Strong stacking interactions result in the fastest electron-transfer kinetics. Electrons are thus transported preferentially through an intrastrand rather than interstrand pathway. Reactant energetics also modulate the distance dependence of DNA-mediated charge transport. These studies may resolve the range of disparate results previously reported, and paradigms must now be developed to describe these properties of the DNA pi-stack, which can range from insulator- to "wire"-like.  相似文献   
317.
安钢高炉炉料冶金性能研究   总被引:1,自引:0,他引:1  
检测和研究了安钢炼铁生产中单一炉料及综合炉料的冶金性能.研究表明安钢自产高碱度烧结矿具有较好的还原性,但其低温还原粉化率却是最高的;酸性球团矿及块矿则有着较好的低温还原粉化指数及良好的熔滴性能,能够与高碱度烧结矿搭配形成合理的综合炉料结构,满足高炉冶炼要求.并提出了安钢综合炉料结构优化方向.  相似文献   
318.
Elemental composition, mass attenuation coefficients (MACs), effective atomic numbers (EANs), and effective electron densities (EEDs) give information about the nuclear applications of materials (dosimetry, shielding, etc.). In this work, MAC of some commercial building glasses were determined using the WinXCom computer program and GATE Monte Carlo code; additionally,EAN and EED of these glasses were also determined using related formulas, after the elemental compositions of the samples were determined by energy dispersive X-ray spectroscopy (EDS) technique. These properties were determined at 59.5 keV (Am-241), 380 keV (Ir-192), 662 keV (Cs-237), 1173 keV (Co-60), and 1332 keV (Co-60). These energies are of interest for any potential nuclear accident. The elemental compositions show the presence of C, O, Na, Mg, Si, and Ca in various percentages; MAC values ranged from about 0.05 to 0.225 cm2/g; EAN also ranged from about 9 to 11and EED is almost constant at all energies considered except at 59.5 keV where higher values were shown. The radiation interaction properties of the investigated glasses showed that they could be used as a dosimeters during emergency radiation exposure situations.  相似文献   
319.
320.
该文针对多焦点多光子显微镜被越来越多地用于生物组织的三维成像。由于三维成像的实时图像数据巨大,开发实时压缩算法将有助于大规模图像数据的采集和存储。基于霍夫曼编码的无损压缩算法和基于离散余弦变换的JPEG有损压缩算法,对多焦点多光子显微镜成像数据的压缩进行初步研究。实验结果表明,基于霍夫曼编码的无损压缩算法压缩率稍低,但无图像信息丢失;基于JPEG编码的有损压缩算法具有较高的压缩率,但是图像信息会有一定程度的丢失。  相似文献   
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