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Integrated Measure (integrate + measure)
Selected AbstractsSystem Complexity As a Measure of Safe Capacity for the Emergency DepartmentACADEMIC EMERGENCY MEDICINE, Issue 11 2006Daniel J. France PhD Objectives System complexity is introduced as a new measure of system state for the emergency department (ED). In its original form, the measure quantifies the uncertainty of demands on system resources. For application in the ED, the measure is being modified to quantify both workload and uncertainty to produce a single integrated measure of system state. Methods Complexity is quantified using an information-theoretic or entropic approach developed in manufacturing and operations research. In its original form, complexity is calculated on the basis of four system parameters: 1) the number of resources (clinicians and processing entities such as radiology and laboratory systems), 2) the number of possible work states for each resource, 3) the probability that a resource is in a particular work state, and 4) the probability of queue changes (i.e., where a queue is defined by the number of patients or patient orders being managed by a resource) during a specified time period. Results An example is presented to demonstrate how complexity is calculated and interpreted for a simple system composed of three resources (i.e., emergency physicians) managing varying patient loads. The example shows that variation in physician work states and patient queues produces different scores of complexity for each physician. It also illustrates how complexity and workload differ. Conclusions System complexity is a viable and technically feasible measurement for monitoring and managing surge capacity in the ED. [source] Integrated local correlation: A new measure of local coherence in fMRI dataHUMAN BRAIN MAPPING, Issue 1 2009Gopikrishna Deshpande Abstract This article introduces the measure of integrated local correlation (ILC) for assessing local coherence in the brain using functional magnetic resonance imaging (fMRI) data and characterizes the measure in terms of reproducibility, the effect of physiological noise, and the dependence on image resolution. The coupling of local neuronal processes influences coherence in a voxel's neighborhood. ILC is defined, for each voxel, as the integration of its spatial correlation function. This integrated measure does not require the specification of a neighborhood and, as demonstrated by experimental data, is effectively independent of image resolution. Respiratory and cardiac fluctuations do not considerably alter the ILC value except in isolated areas in and surrounding large vessels. With resting-state fMRI data, ILC was demonstrated to be tissue-specific, higher in gray matter than white matter, and reproducible across consecutive runs in healthy individuals. Within the gray matter, ILC was found to be higher in the default mode network, particularly the posterior and anterior cingulate cortices. Comparing ILC maps obtained from resting state and continuous motor task data, we observed reduced local coherence in the default mode network during the task. Finally, we compared ILC and regional homogeneity by examining their ability to discriminate between gray and white matters in resting state data and found ILC to be more sensitive. Hum Brain Mapp 2009. © 2007 Wiley-Liss, Inc. [source] Reduced fecundity and offspring performance in small populations of the declining grassland plants Primula veris and Gentiana luteaJOURNAL OF ECOLOGY, Issue 1 2000Marc Kéry Summary 1,We studied reproduction and offspring performance in relation to population size in the declining self-incompatible perennials Primula veris and Gentiana lutea. In both species, reproduction was strongly reduced in small populations, where plants produced fewer seeds per fruit and per plant. Total seed mass per plant was higher in large populations, but individual seeds were smaller, indicating a trade-off between seed number and size. Reproduction was depressed most strongly in populations consisting of less than c. 200 (P. veris) and c. 500 plants (G. lutea), respectively. 2,The inclusion of plant size (an integrated measure of habitat quality) in the statistical models did not change the relationships between fecundity and population size. Pollen limitation or inbreeding depression in small populations are therefore more likely explanations for these patterns than is habitat quality. 3,Germination rate and survival of seedlings in a common environment was not related to population size in either species, although P. veris developed into larger rosettes when seeds were derived from large populations. This suggests that inbreeding depression occurs in small populations of P. veris. 4,In a factorial fertilizer-by-competition experiment with P. veris, offspring from larger populations grew significantly larger and responded more strongly to fertilizer. For this declining species genetic deterioration as a result of habitat fragmentation may therefore aggravate the effects of environmental changes such as habitat eutrophication. 5,Our results suggest that small populations may face an increased short-term risk of extinction because of reduced reproduction, and an increased long-term risk because they are less able to respond to environmental changes. [source] Worldwide allele frequencies of the human apolipoprotein E gene: Climate, local adaptations, and evolutionary historyAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 1 2010Dan T.A. Eisenberg Abstract The ,4 allele of the apolipoprotein E (APOE) gene is associated with increased cholesterol levels and heart disease. Population allele frequencies of APOE have previously been shown to vary, with ,4 frequencies generally increasing with latitude. We hypothesize that this trend resulted from natural selection protecting against low-cholesterol levels. In high-latitude cold environments and low-latitude hot environments, metabolic rate is elevated, which could require higher cholesterol levels. To explore this hypothesis, we compiled APOE allele frequencies, latitude, temperature, and elevation from populations around the world. ,4 allele frequencies show a curvilinear relationship with absolute latitude, with lowest frequencies found in the mid-latitudes where temperatures generally require less expenditure on cooling/thermogenesis. Controlling for population structure in a subset of populations did not appreciably change this pattern of association, consistent with selection pressures that vary by latitude shaping ,4 allele frequencies. Temperature records also predict APOE frequency in a curvilinear fashion, with lowest ,4 frequencies at moderate temperatures. The model fit between historical temperatures and ,4 is less than between latitude and ,4, but strengthened after correcting for estimated temperature differences during the Paleolithic. Contrary to our hypothesis, we find that elevation did not improve predictive power, and an integrated measure of the cholesterol effect of multiple APOE alleles was less related to latitude than was ,4 alone. Our results lend mixed support for a link between past temperature and human APOE allele distribution and point to the need to develop better models of past climate in future analyses. Am J Phys Anthropol 143:13,20, 2010. © 2010 Wiley-Liss, Inc. [source] Evaluating social performance in the context of an ,audit culture': a pilot social review of a gold mine in Papua New GuineaCORPORATE SOCIAL RESPONSIBILITY AND ENVIRONMENTAL MANAGEMENT, Issue 2 2008Martha Macintyre Abstract The growth of sustainable development frameworks that emphasize the social dimension has created a need for new approaches to evaluate social performance. The paper describes the design and pilot of a social review conducted at the Lihir Gold Mine in Papua New Guinea. The aim was to investigate more integrated measures , understood as combining qualitative and quantitative measures, and bridging international and local community standards , of social performance. The paper discusses the demands of time and resources placed on a range of stakeholders as part of a review. It then identifies impediments to developing integrated approaches, and analyses these with reference to Power's (1999, 2003) discussion of an emerging audit culture, which focuses on management systems rather than first-order questions of quality and performance. The authors conclude that, while an audit culture influenced this pilot study, an integrated approach on these two dimensions remains an achievable goal. Copyright © 2007 John Wiley & Sons, Ltd and ERP Environment. [source] | ||||||||||