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Similar Assessments (similar + assessment)
Selected AbstractsToxicity of the molybdate anion in soil is partially explained by effects of the accompanying cation or by soil pHENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 6 2010Jurgen Buekers Abstract Previous studies have shown that toxicity of cationic trace metals in soil is partially confounded by effects of the accompanying anions. A similar assessment is reported here for toxicity of an oxyanion, i.e., molybdate (MoO), the soil toxicity of which is relatively unexplored. Solubility and toxicity were compared between the soluble sodium molybdate (Na2MoO4) and the sparingly soluble molybdenum trioxide (MoO3). Confounding effects of salinity were excluded by referencing the Na2MoO4 effect to that of sodium chloride (NaCl). The pH decrease from the acid MoO3 amendment was equally referenced to a hydrochloric (HCl) treatment or a lime-controlled MoO3 treatment. The concentrations of molybdenum (Mo) in soil solution or calcium chloride (CaCl2) 0.01,M extracts were only marginally affected by either MoO3 or Na2MoO4 as an Mo source after 10 to 13 days of equilibration. Effects of Mo on soil nitrification were fully confounded by associated changes in salinity or pH. Effects of Mo on growth of wheat seedlings (Triticum aestivum L) were more pronounced than those on nitrification, and toxicity thresholds were unaffected by the form of added Mo. The Mo thresholds for wheat growth were not confounded by pH or salinity at incipient toxicity. It is concluded that oxyanion toxicity might be confounded in relatively insensitive tests for which reference treatments should be included. Environ. Toxicol. Chem. 2010;29:1274,1278. © 2010 SETAC [source] A Decision-Making Framework for Sediment ContaminationINTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT, Issue 3 2005Peter M. Chapman Abstract A decision-making framework for determining whether or not contaminated sediments are polluted is described. This framework is intended to be sufficiently prescriptive to standardize the decision-making process but without using "cook book" assessments. It emphasizes 4 guidance "rules": (1) sediment chemistry data are only to be used alone for remediation decisions when the costs of further investigation outweigh the costs of remediation and there is agreement among all stakeholders to act; (2) remediation decisions are based primarily on biology; (3) lines of evidence (LOE), such as laboratory toxicity tests and models that contradict the results of properly conducted field surveys, are assumed incorrect; and (4) if the impacts of a remedial alternative will cause more environmental harm than good, then it should not be implemented. Sediments with contaminant concentrations below sediment quality guidelines (SQGs) that predict toxicity to less than 5% of sediment-dwelling infauna and that contain no quantifiable concentrations of substances capable of biomagnifying are excluded from further consideration, as are sediments that do not meet these criteria but have contaminant concentrations equal to or below reference concentrations. Biomagnification potential is initially addressed by conservative (worst case) modeling based on benthos and sediments and, subsequently, by additional food chain data and more realistic assumptions. Toxicity (acute and chronic) and alterations to resident communities are addressed by, respectively, laboratory studies and field observations. The integrative decision point for sediments is a weight of evidence (WOE) matrix combining up to 4 main LOE: chemistry, toxicity, community alteration, and biomagnification potential. Of 16 possible WOE scenarios, 6 result in definite decisions, and 10 require additional assessment. Typically, this framework will be applied to surficial sediments. The possibility that deeper sediments may be uncovered as a result of natural or other processes must also be investigated and may require similar assessment. [source] The European Male Ageing Study (EMAS): design, methods and recruitmentINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 1 2009David M. Lee Summary Life expectancy is increasing in most developed countries, in part due to improved socioeconomic conditions and in part to advances in healthcare. It is widely acknowledged that the promotion of healthy ageing by delaying, minimizing or preventing disabilities or diseases is one of the most important public health objectives in this century. In contrast to the menopausal transition in females, we know relatively little about the contribution of androgens and anabolic hormones to the quality of ageing in men. The European Male Ageing Study (EMAS) is a multicentre prospective cohort designed to examine the prevalence, incidence and geographical distribution of gender-specific and general symptoms of ageing in men, including their endocrine, genetic and psychosocial predictors. Men aged 40,79 years were recruited from eight European centres: Florence (Italy), Leuven (Belgium), Lodz (Poland), Malmö (Sweden), Manchester (UK), Santiago de Compostela (Spain), Szeged (Hungary) and Tartu (Estonia). Subjects were recruited from population registers and those who agreed to take part completed a detailed questionnaire including aspects of personal and medical history, lifestyle factors and sexual function. Objective measures of body size, cognition, vision, skeletal health and neuromuscular function were obtained. Blood and DNA specimens were collected for a range of biochemical and genetic analyses. After an average of 4 years, it is planned to resurvey the participants with similar assessments. A total of 3369 men with a mean age of 60 ± 11 years were recruited. The mean centre response rate was 43%, and highest in those aged 50,59 years. Those who participated were marginally younger than those who were invited but declined to participate (60.0 vs. 61.1 years). Participants left education slightly later than a sample of non-participants, though there were no consistent differences in levels of general health, physical activity, or smoking. EMAS will provide new population-based data concerning the main features that characterize ageing in men and its critical determinants, particularly with reference to age-related changes in hormone levels. Such information is an important prerequisite to develop effective strategies to reduce age-related disabilities and optimise health and well-being into old-age. [source] Eating Disorder Examination-Questionnaire as a measure of change in patients with bulimia nervosaINTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 2 2005Robyn Sysko MS Abstract Objective The current study evaluated the agreement between the Eating Disorder Examination and the Eating Disorder Examination-Questionnaire in assessing eating disorder pathology in a sample of women with bulimia nervosa. Method Patients with broadly defined bulimia nervosa were enrolled in a double-blind, placebo-controlled treatment study of fluoxetine, with and without guided self-help. The current study presents information from 50 patients with data from both the EDE and EDE-Q at study entry and treatment termination. Results The EDE and EDE-Q produced more similar scores for compensatory behaviors (vomiting/laxative use) than complex eating-disordered features (binge eating/importance of shape and weight) at the pretreatment and posttreatment assessments, and for change during the study. Discussion The EDE and EDE-Q are highly correlated for many of the behavioral and attitudinal features of bulimia nervosa. There is substantial variability in agreement for individual patients, but on average, the EDE and EDE-Q will yield similar assessments of eating disorder symptoms and change in symptoms over time. © 2005 by Wiley Periodicals, Inc. [source] Interfragmentary surface area as an index of comminution severity in cortical bone impactJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 3 2005Christina L. Beardsley Abstract A monotonic relationship is expected between energy absorption and fracture surface area generation for brittle solids, based on fracture mechanics principles. It was hypothesized that this relationship is demonstrable in bone, to the point that on a continuous scale, comminuted fractures created with specific levels of energy delivery could be discriminated from one another. Using bovine cortical bone segments in conjunction with digital image analysis of CT fracture data, the surface area freed by controlled impact fracture events was measured. The results demonstrated a statistically significant (p < 0.0001) difference in measured de novo surface area between three specimen groups, over a range of input energies from 0.423 to 0.702 J/g. Local material properties were also incorporated into these measurements via CT Hounsfield intensities. This study confirms that comminution severity of bone fractures can indeed be measured on a continuous scale, based on energy absorption. This lays a foundation for similar assessments in human injuries. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source] A rapid method for assessment of plant residue qualityJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 5 2003Praveen-Kumar Abstract A simple, reproducible and new method (modified dehydrogenase activity measurement after 72 h; DHA 72) was developed to assess plant residue quality for decomposition. The method resulted in similar assessments of residue quality than measurements of the C:N ratio, lignin:N ratio, and lignin and polyphenol concentration (PRQI). Among 25 plant residues tested, there was a large variation of DHA 72 as found in other well-established methods. Based on cluster analysis, plant residues were grouped in four different classes; highly decomposable, moderately decomposable, slowly decomposable, and least decomposable. It is concluded that DHA 72 can very well be used to screen plant residues for residue quality judgment. The proposed method is very simple and easy to handle. [source] USING STREAM BIOASSESSMENT PROTOCOLS TO MONITOR IMPACTS OF A CONFINED SWINE OPERATION,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 3 2006Jeffrey Jack ABSTRACT: The processing of waste from confined animal feeding operations (CAFOs) presents a major environmental challenge. Treatment of waste and subsequent land application is a common best management practice (BMP) for these operations in Kentucky, USA, but there are few data assessing the effect of runoff from such operations on aquatic communities. The authors sampled a stream bordering a CAFO with a land application program to determine if runoff from the fertilized fields was adversely affecting stream communities. Water chemistry, periphyton, and macroinvertebrate samples from riffle habitats downstream of the CAFO were compared to samples collected from an upstream site and a control stream in 1999 and 2000. Riffle communities downstream of the fertilized fields had higher chlorophyll a levels than other sites, but there were no significant differences in macroinvertebrate numbers or in biometrics such as taxa richness among the sites. The BMP in place at this site may be effective in reducing this CAFO's impact on the stream; however, similar assessments at other CAFO sites should be done to assess their impacts. Functional measures such as nutrient retention and litter decomposition of streams impacted by CAFOs should also be investigated to ensure that these operations are not adversely affecting stream communities. [source] Patients' Evaluation of Two Occlusal Schemes for Implant OverdenturesCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 3 2008BHealSc, John M. Aarts BEd, MhealSc, PGDipCDTech ABSTRACT Background: There is an absence of conclusive evidence for occlusal schemes in implant overdentures. Purpose: To investigate the consequences of two different occlusal schemes on levels of satisfaction for patients wearing implant overdentures. Materials and Methods: Within an existing randomized controlled clinical trial, a physiologic occlusal scheme was compared with a lingualized occlusal scheme for 18 selected participants all with implant overdentures. Nine participants had conventional maxillary complete dentures opposing mandibular 2-implant overdentures; a further nine participants had maxillary 3-implant overdentures opposing mandibular 2-implant overdentures. All participants recruited had been wearing their original prostheses for 3 years with a bilateral balance occlusal scheme. The participants' existing satisfaction levels, as a baseline, were determined using visual analogue scale questionnaires. They were followed by similar assessments of two further occlusal schemes using 2-month assessment periods. On completion of the study, the participants selected their preferred occlusal scheme and semiformal interviews were conducted to assess the rationale for their choices. Results: Baseline data showed all the participants had pre-existing high satisfaction levels. Thereafter, of those participants that received lingualized occlusion first, 55.6% reported that the physiologic occlusion was better than lingualized occlusion. For those participants who received the physiologic occlusion first, 85.7% reported that physiologic occlusion was better than lingualized occlusion. On completion of the study, 64.7% of the participants preferred the physiologic occlusion, 35.3% preferred the lingualized occlusion. However, when the two groups' satisfaction scores were modeled using the three main key indicator questions (general satisfaction, general ability to chew, or general function), there were no significant differences between them. Conclusions: Within the limitations of a small number of participants, the majority of them still indicated a preference for a physiologic occlusion for implant overdentures. Improved function was given as the main indicator for that preference. Having implant overdentures in one or both jaws is not a formative factor in patient's opinions on occlusal schemes. [source] | ||||||||||||||||