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Criterion Value (criterion + value)
Selected AbstractsResponse of macroinvertebrates to copper and zinc in a stream mesocosmENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2002Christopher W Hickey Abstract Metal pollution of streams and rivers is recognized as one of the major concerns for management of freshwaters. Macroinvertebrate communities were established within 12 artificial streams and exposed to three replicated concentrations of a metals mixture (copper and zinc) for 34 d. The cumulative criterion units (CCU = ,[metals]/hardness-adjusted U.S. Environmental Protection Agency [U.S. EPA] 1996 chronic criterion value) of total metals in the low, medium, and high treatments were 2.4, 5.9, and 18 CCUs. Zinc comprised approximately 75% of the CCUs in each of the treatments. Effects on taxa richness and the number of taxa in the orders Ephemeroptera, Plecoptera, and Trichoptera (EPT) were moderate at the high exposure concentration (,23% and ,26% respectively, p < 0.05). All of the five major mayfly species showed near extinction, whereas four of the seven caddisflies showed stimulation (up to +121%) and three were reduced (up to ,76%). Redundancy analysis for this metal gradient indicated that 94% of the variance in community structure was explained by three quantitative variables: total mayfly abundance, a mollusk (Potamopyrgus antipodarum) abundance, and the number of EPT individuals, indicating that multiple indices do provide improved predictors of metal stress. Most species showed a threshold response relationship, whereas some community indicators showed apparent hormetic responses (e.g., number of mayfly taxa, total taxa, and number of EPT taxa). Model concentration-response relationships with generalized linear models were used to provide threshold of 20% effective concentration values for species and community metrics. Threshold effect values ranged upwards of 1.4 CCUs, indicating that U.S.EPA chronic criteria would be protective of species and community responses. [source] Comparison of three current staging systems for hepatocellular carcinoma: Japan integrated staging score, new Barcelona Clinic Liver Cancer staging classification, and Tokyo scoreJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 3 2008Hobyung Chung Abstract Background and Aim:, Although various staging systems for hepatocellular carcinoma (HCC) have been developed in recent years, there is no worldwide consensus which staging system is best. The aim of the present study was to compare the performance of the currently developed three staging systems: the Japan integrated staging (JIS) score, new Barcelona Clinic Liver Cancer (BCLC) staging classification, and the Tokyo score. Methods:, A total of 290 consecutive patients with HCC before initial treatment at Kinki University between January 1999 and December 2001 were included. The patients were stratified according to the three staging systems, and the performance of the staging systems was compared using survival time as the only outcome measure. Results:, There were significant differences between all stages in the JIS score, while no significant difference was found between stages C and D in the BCLC staging classification and between all the scores, except between scores 0 and 1 and 2 and 3 in the Tokyo score. For all patients (n = 290), the radical treatment group (n = 208) and the non-radical treatment group (n = 82), the likelihood ratio ,2 -test showed the highest value, and the Akaike information criterion value was lowest in the JIS score. Conclusion:, The JIS score provided the best prognostic stratification in a Japanese cohort of HCC patients who were mainly diagnosed at early stages and treated with radical therapies. [source] Correlation of echocardiography parameters with cardiac magnetic resonance imaging in transfusion-dependent thalassaemia majorEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 1 2007Athanassios Aessopos Abstract Background and objective:,Heart iron load (cardiac Fe) can be indirectly quantified by cardiac magnetic resonance (CMR) T2*. CMR accessibility is limited, whereas echocardiography (Echo) is relatively inexpensive and readily available. The objective was to find Echo parameters that may be useful for predicting cardiac Fe. Design and methods:,We compared a number of parameters derived from Echo to cardiac Fe in 142 thalassaemia major patients who had undergone a CMR study. Results:,All patients with decreased left ventricular (LV) function had cardiac Fe. After removing those patients from the analysis, the total diameter index (Tdi) >5.57 cms/m2, left atrial diameter index >2.41 cm/m2, and the diastolic parameter E/A > 1.96 were highly specific (91.4%, 97.1% and 96.9% respectively) but had low sensitivity (31.8%, 20.45% and 21.8%) in predicting iron load. A right ventricular index >1.47 cm/m2, LV systolic index >2.26 cm/m2 or Tdi >6.26 cm/m2 discriminated between patients with no, or mild to moderate cardiac Fe from those with heavy load, with specificity of 91%, 98.5%, and 98.5%, respectively, but with low sensitivity. Interpretation and conclusions:,Echo parameters for cardiac Fe prediction have restricted value, whereas CMR is essential to assess cardiac Fe. However, patients with decreased LV systolic function should be considered a priori as having cardiac Fe, and chelation therapy should be intensified. This also applies to patients who have the above-described Echo criterion values, even if CMR is not available. Once a patient is found by CMR to have cardiac Fe, then the above Echo criterion values may be useful for ongoing monitoring. [source] Inherent biases in decision support systems: the influence of optimistic and pessimistic DSS on choice, affect, and attitudesJOURNAL OF BEHAVIORAL DECISION MAKING, Issue 1 2008Pekka Korhonen Abstract This study investigates the influence of a decision aid on decision makers' model-based choices, emotions during the use of the model, and attitudes towards the model. A time allocation decision model was biased to purposefully provide optimistic or pessimistic criterion levels, on which subjects based their allocations. The results of our experiment indicate that the degree of "optimism" and "pessimism" inherent in the decision model had a significant impact on the decision maker's choices of criterion values, with optimism leading to higher criterion level choices and pessimism to lower levels. Furthermore, compared to pessimistic models, optimistic models significantly improved the decision makers' emotional states and, to some degree, their attitudes towards the decision aid. The implications of these conscious and sub-conscious influences on decision makers' choices, emotions, and attitudes are discussed and the need for model-builders and users to be aware of them is highlighted. Copyright © 2007 John Wiley & Sons, Ltd. [source] | ||||||||||