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Assessment Models (assessment + models)
Selected AbstractsEmpirical and modeling evidence of regional atmospheric transport of current-use pesticidesENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2004Derek C. G. Muir Abstract Water samples from 30 lakes in Canada and the northeastern United States were analyzed for the occurrence of 27 current-use pesticides (CUPs). Eleven CUPs were frequently detected in lakes receiving agricultural inputs as well as in remote lakes hundreds of kilometers from known application areas. These included the triazine herbicide atrazine and its desethylated degradation product; the herbicides alachlor, metolachlor, and dacthal; the organophosphate insecticides chlorpyrifos, diazinon, and disulfoton; the organochlorine insecticides ,-endosulfan and lindane; and the fungicides chlorothalonil and flutriafol. For six of the pesticides, empirical half-distances on the order of 560 to 1,820 km were estimated from the water-concentration gradient with latitude. For most of the pesticides, a suite of assessment models failed to predict such atmospheric long-range transport behavior, unless the effect of periods of lower hydroxyl radical concentrations and dry weather were taken into account. Observations and model results suggest that under the conditions prevailing in south-central Canada (relatively high latitude, low precipitation rates), many CUPs will be able to undergo regional-scale atmospheric transport and reach lakes outside areas of agricultural application. When assessing the potential of fairly reactive and water-soluble substances to undergo long-range transport, it is imperative to account for periods of no precipitation, to assure that degradation rate constants are correct, and to apply oxidant concentrations that are valid for the region and time period of interest. [source] Partitioning of metals (Cd, Co, Cu, Ni, Pb, Zn) in soils: concepts, methodologies, prediction and applications , a reviewEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 4 2009F. Degryse Summary Prediction of the fate of metals in soil requires knowledge of their solid,liquid partitioning. This paper reviews analytical methods and models for measuring or predicting the solid,liquid partitioning of metals in aerobic soils, and collates experimental data. The partitioning is often expressed with an empirical distribution coefficient or Kd, which gives the ratio of the concentration in the solid phase to that in the solution phase. The Kd value of a metal reflects the net effect of various reactions in the solid and liquid phases and varies by orders of magnitude among soils. The Kd value can be derived from the solid,liquid distribution of added metal or that of the soil-borne metal. Only part of the solid-phase metal is rapidly exchangeable with the solution phase. Various methods have been developed to quantify this ,labile' phase, and Kd values based on this phase often correlate better with soil properties than Kd values based on total concentration, and are more appropriate to express metal ion buffering in solute transport models. The in situ soil solution is the preferred solution phase for Kd determinations. Alternatively, water or dilute-salt extracts can be used, but these may underestimate in situ concentrations of dissolved metals because of dilution of metal-complexing ligands such as dissolved organic matter. Multi-surface models and empirical models have been proposed to predict metal partitioning from soil properties. Though soil pH is the most important soil property determining the retention of the free metal ion, Kd values based on total dissolved metal in solution may show little pH dependence for metal ions that have strong affinity for dissolved organic matter. The Kd coefficient is used as an equilibrium constant in risk assessment models. However, slow dissociation of metal complexes in solution and slow exchange of metals between labile and non-labile pools in the solid phase may invalidate this equilibrium assumption. [source] Review and comparison between the Wells,Riley and dose-response approaches to risk assessment of infectious respiratory diseasesINDOOR AIR, Issue 1 2010G. N. Sze To Abstract, Infection risk assessment is very useful in understanding the transmission dynamics of infectious diseases and in predicting the risk of these diseases to the public. Quantitative infection risk assessment can provide quantitative analysis of disease transmission and the effectiveness of infection control measures. The Wells,Riley model has been extensively used for quantitative infection risk assessment of respiratory infectious diseases in indoor premises. Some newer studies have also proposed the use of dose-response models for such purpose. This study reviews and compares these two approaches to infection risk assessment of respiratory infectious diseases. The Wells,Riley model allows quick assessment and does not require interspecies extrapolation of infectivity. Dose-response models can consider other disease transmission routes in addition to airborne route and can calculate the infectious source strength of an outbreak in terms of the quantity of the pathogen rather than a hypothetical unit. Spatial distribution of airborne pathogens is one of the most important factors in infection risk assessment of respiratory disease. Respiratory deposition of aerosol induces heterogeneous infectivity of intake pathogens and randomness on the intake dose, which are not being well accounted for in current risk models. Some suggestions for further development of the risk assessment models are proposed. Practical Implications This review article summarizes the strengths and limitations of the Wells,Riley and the dose-response models for risk assessment of respiratory diseases. Even with many efforts by various investigators to develop and modify the risk assessment models, some limitations still persist. This review serves as a reference for further development of infection risk assessment models of respiratory diseases. The Wells,Riley model and dose-response model offer specific advantages. Risk assessors can select the approach that is suitable to their particular conditions to perform risk assessment. [source] Effects of environmental variables on fish feeding ecology: implications for the performance of baited fishing gear and stock assessmentJOURNAL OF FISH BIOLOGY, Issue 6 2004A. W. Stoner The effectiveness of baited fishing gear ultimately depends upon behaviour of the target species , activity rhythms, feeding motivation, and sensory and locomotory abilities. While any environmental parameter that mediates feeding or locomotion can have an important influence on the active space presented by the bait and fish catchability, few biologists have considered how such variation in behaviour might affect catch per unit effort (CPUE) and the resultant stock abundance estimates or population parameters. This review reveals that environment-related variation in feeding behaviour can act through four different mechanisms: metabolic processes, sensory limitations, social interactions and direct impacts. Water temperature, light level, current velocity and ambient prey density are likely to have largest effects on fish catchability, potentially affecting variation in CPUE by a factor of ten. Feeding behaviour is also density-dependent, with both positive and negative effects. Over time and geographic space a target species can occupy wide ranges of environmental conditions, and in certain cases, spatial and temporal variation in feeding biology could have a larger impact on CPUE than patterns of abundance. Temperature, light and current can be measured with relative facility and corrections to stock assessment models are feasible. Making corrections for biological variables such as prey density and bait competitors will be more difficult because the measurements are often not practical and relationships to feeding catchability are more complex and poorly understood. There is a critical need for greater understanding of how environmental variables affect feeding-related performance of baited fishing gear. A combination of field observations and laboratory experiments will be necessary to parameterize stock assessment models that are improved to accommodate variation in fish behaviour. Otherwise, survey data could reveal more about variation in behaviour than abundance trends. [source] Pre- and posttest evaluation of a breast cancer risk assessment program for nurse practitionersJOURNAL OF THE AMERICAN ACADEMY OF NURSE PRACTITIONERS, Issue 7 2010FAANP (Associate Professor), FNP-C, Quannetta T. Edwards BSN, WHCNP-C Abstract Purpose: Numerous studies have shown that healthcare providers, including nurse practitioners (NPs) fail to provide breast cancer risk assessment (BrCRA) in primary care settings. A potential barrier to the use of BrCRA is insufficient knowledge or training of risk assessment. The purpose of this study was to analyze the outcome of a BrCRA program developed to enhance NPs' knowledge of risk assessment and use of empiric risk assessment models. Data sources: Thirty-five NPs participated in a before-after (pretest,posttest design) study evaluating the effectiveness of a BrCRA education program conducted at a national NP conference. Demographics, pre/post knowledge, and course satisfaction measures were all examined as a part of this pilot study. Conclusion: Continuing education through the implementation of a BrCRA program significantly increased NPs knowledge in assessing breast cancer risk and the use of empiric risk assessment models. Implications for practice: Many healthcare providers, including NPs, are inadequately prepared to assess a woman's risk for breast cancer. Understanding breast cancer risk assessment is essential if NPs are to provide appropriate counseling, management, and referral strategies needed to reduce a woman's risk for developing the disease. Continuing education provides one means to enhance NP's knowledge of BrCRA. [source] EPA'S BASINS MODEL: GOOD SCIENCE OR SERENDIPITOUS MODELING?,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 3 2000Ray C. Whittemore ABSTRACT: Better Assessment Science Integrating Point and Non-point Sources (BASINS) is a geographic-based watershed assessment tool developed by EPA's Office of Water to help states more efficiently target and evaluate water-bodies that are not meeting water quality standards. BASINS (EPA, 1996a, 1998) brings together data on water quality and quantity, land uses, point source loadings, and other related spatial data with supporting nonpoint and water quality models at a quicker and more effective pace. EPA developed BASINS, to better integrate point and nonpoint source water quality assessments for the Nation's 2100+ watersheds. In its zeal to achieve this endpoint, EPA has initiated a simplistic approach that was expected to grow through scientific enhancements as TMDL developers become more familiar with modeling requirements. BASINS builds upon federal databases of water quality conditions and point source loadings for numerous parameters where quality assurance is suspect in some cases. Its design allows comprehensive assessments and modeling in typical Total Maximum Daily Load (TMDL) computations. While the TMDL utility is the primary reason BASINS was developed, other longer-range water quality assessments will become possible as the Agency expands the suite of assessment models and databases in future releases. The simplistic approach to modeling and user-friendly tools gives rise, however, to technical and philosophical concerns related to default data usage. Seamless generation of model input files and the failure of some utilities to work properly suggest to NCASI that serious problems may still exist and prompts the need for a more rigorous peer-review. Furthermore, sustainable training becomes paramount, as some older modelers will be unfamiliar with Geographic Information System (GIS) technology and associated computer skills. Overall, however, BASINS was judged to be an excellent beginning tool to meet the complex environmental modeling needs in the 21st Century. [source] Cattell,Horn,Carroll cognitive-achievement relations: What we have learned from the past 20 years of researchPSYCHOLOGY IN THE SCHOOLS, Issue 7 2010Kevin S. McGrew Contemporary Cattell,Horn,Carroll (CHC) theory of cognitive abilities has evolved over the past 20 years and serves as the theoretical foundation for a number of current cognitive ability assessments. CHC theory provides a means by which we can better understand the relationships between cognitive abilities and academic achievement, an important component of learning disabilities identification and instructional planning. A research synthesis of the extant CHC cognitive-achievement (COG-ACH) research literature is reported. Systematic and operationally defined research synthesis procedures were employed to address limitations present in the only prior attempted synthesis. Nineteen studies met the criteria for inclusion, which yielded 134 analyses. The 134 analyses were organized by three age groups (6,8, 9,13, and 14,19) and by four achievement domains (basic reading skills, reading comprehension, basic math skills, and math reasoning). The results reveal a much more nuanced set of CHC COG-ACH relations than was identified in the only prior review because of (a) breadth of cognitive abilities and measures (broad vs. narrow), (b) breadth of achievement domains (e.g., basic reading skills and reading comprehension vs. broad reading), and (c) developmental (age) status. The findings argue for selective, flexible, and referral-focused intelligence testing, particularly in the context of emerging Response to Intervention (RTI) assessment models. The results suggest that narrow CHC abilities should be the primary focus of instructionally relevant intelligence testing. Furthermore, the finding that more than 90% of the available research is based on the Woodcock,Johnson Battery argues for significant caution in generalizing the findings to other batteries. CHC-based COG-ACH research with other intelligence batteries is recommended. © 2010 Wiley Periodicals, Inc. [source] Changes in yearling rhesus monkeys' relationships with their mothers after sibling birthAMERICAN JOURNAL OF PRIMATOLOGY, Issue 4 2001B.J. Devinney Abstract The birth of a new sibling is believed to signify an abrupt and important transition in a young primate's relationship with its mother,one that is of potential importance from at least three theoretical perspectives: attachment theory, parent,offspring conflict theory, and dynamic assessment models. This study examines changes in relationships between free-ranging yearling rhesus monkeys (Macaca mulatta) and their mothers concomitant with the birth of the mother's next infant, and tests predictions derived from each theoretical perspective. We observed 31 yearling rhesus on Cayo Santiago, Puerto Rico, 3 months before and 3 months after their siblings' births, using focal animal sampling methods. Changes in measures related to mother,yearling interaction and yearling distress were examined using repeated-measures analysis of variance. After sibling birth, mothers and yearlings abruptly reduced amounts of time in contact and increased amounts of time at a distance and out of sight of one another. Mothers and yearlings played approximately equal roles in bringing about decreases in proximity, and yearlings took the primary roles in bringing about decreases in contact. Rates of maternal aggression toward yearlings increased immediately and markedly after birth, possibly providing yearlings with early cues regarding subsequent decreased levels of maternal care. There were no marked increases in overt signs of yearling distress (e.g., vocalizations or tantrums) following the births. We conclude that yearlings generally acquiesced to reduced levels of care, responding behaviorally with increased independence and maturity. In this sense, our study provides preliminary support for dynamic assessment models over attachment theory and parent,offspring conflict theory models. Am. J. Primatol. 54:193,210, 2001. © 2001 Wiley-Liss, Inc. [source] Identification of behavioral function in public schools and a clarification of termsBEHAVIORAL INTERVENTIONS, Issue 1 2007Kelly Kates-McElrath The discipline-related component of Individuals with Disabilities Education Act (IDEA) requires that schools conduct a Functional Behavioral Assessment (FBA) when a student's behavior disrupts the educational environment and/or results in suspension from school. Applied behavior analysts often make a distinction between the terms functional assessment/functional behavioral assessment, and functional analysis yet there exists no consensus on how that distinction should be made. A relevant review of the literature was conducted to identify research articles using functional analysis or functional assessment methodology in public school settings in an effort to identify the specific procedures employed by each. Results of the review support the existence of a discrepancy between proposed and actual school-based assessment models, as well as other claims regarding functional assessment research. We address the problem of distinguishing between the terms assessment and analysis as they relate to procedures employed to determine behavioral function of students exhibiting aberrant behavior. A clarification of terms is proposed. Copyright © 2007 John Wiley & Sons, Ltd. [source] | ||||||||||||||||