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PubMed2005

Safety assessment methodology in management of spent sealed sources.

Environmental hazards can be caused from radioactive waste after their disposal. It was therefore important that safety assessment methodologies be developed and established to study and estimate the possible hazards, and institute certain safety methodologies that lead and prevent the evolution of these hazards. Spent sealed sources are specific type of radioactive waste. According to IAEA definition, spent sealed sources are unused sources because of activity decay, damage, misuse, loss, or theft. Accidental exposure of humans from spent sealed sources can occur at the moment they become spent and before their disposal. Because of that reason, safety assessment methodologies were tailored to suit the management of spent sealed sources. To provide understanding and confidence of this study, validation analysis was undertaken by considering the scenario of an accident that occurred in Egypt, June 2000 (the Meet-Halfa accident from an iridium-192 source). The text of this work includes consideration related to the safety assessment approaches of spent sealed sources which constitutes assessment context, processes leading an active source to be spent, accident scenarios, mathematical models for dose calculations, and radiological consequences and regulatory criteria. The text also includes a validation study, which was carried out by evaluating a theoretical scenario compared to the real scenario of Meet-Halfa accident depending on the clinical assessment of affected individuals.

Environment↗

PubMed2005

How powerful is ARAMIS methodology in solving land-use issues associated with industry based environmental and health risks?

The first experience on how a part of the ARAMIS methodology has contributed to demonstration of safety in the licensing process in Slovenia for a new Seveso II plant is described. There are two foci of this description: first, trustworthy of the methodology for evaluating safety, and second, the role of a land-use plan in issuing a construction permit for the new plant. In the context of the first focus, we present why has been safety report first rejected by the regulator, and later-on accepted after applying components of the ARAMIS methodology in its revised version. In the context of the second focus, we discuss a relationship between the land-use plan and the licensing process for the new plant. The outcomes of this Seveso II plant licensing case are that the ARAMIS approach, in spite it was still under development when applied, is more transparent and credible comparing to the others, which have also been applied. This is related to the demonstration of how safety management system and general safety behaviour is integrated into the overall management policy. The conclusions take into account regulator's response in the licensing process.

Accidents, Occupational↗

PubMed2005

A global view on ARAMIS, a risk assessment methodology for industries in the framework of the SEVESO II directive.

The ARAMIS methodology was developed in an European project co-funded in the fifth Framework Programme of the European Commission with the objective to answer the specific requirements of the SEVESO II directive. It offers an alternative to purely deterministic and probabilistic approaches to risk assessment of process plants. It also answers the needs of the various stakeholders interested by the results of the risk assessment for land use or emergency planning, enforcement or, more generally, public decision-making. The methodology is divided into the following major steps: identification of major accident hazards (MIMAH), identification of the safety barriers and assessment of their performances, evaluation of safety management efficiency to barrier reliability, identification of reference accident scenarios (MIRAS), assessment and mapping of the risk severity of reference scenarios and of the vulnerability of the plant surroundings. The methodology was tested during five case studies, which provided useful information about the applicability of the method and, by identifying the most sensitive parts of it opened way to new research activity for an improved industrial safety.

Causality↗

PubMed2005

Determining the performance of a commercial air purification system for reducing airborne contamination using model micro-organisms: a new test methodology.

The performance of a duct-mounted air disinfection system, designed to reduce airborne pathogens in the hospital environment, was determined using a new testing methodology. The methodology places the equipment in a test duct, a microbial aerosol is generated and then sampled simultaneously before and after the test system. This allows a percentage efficiency value to be calculated. The air disinfection system is a novel chemical-coated filter and ultraviolet (UV) radiation air purification system, operating at a flow rate of 500 m(3)/h, against aerosols of MS2 phage and Mycobacterium vaccae (surrogates of viral and mycobactericidal pathogens). A three UV lamp system was effective against airborne phages, removing an average of 97.34% of the aerosolized challenge. With the UV component switched off, the average efficiency dropped to 61.46%. This demonstrates that the chemical-coated filter component plays a more significant role than the UV radiation in destroying phages. When six UV lamps were used, the system was able to remove mycobacteria with an efficiency exceeding 99.99%. This test methodology can be used to assess manufacturers' claims of efficacy of equipment against airborne micro-organisms in the hospital environment.

Air Microbiology↗

PubMed2004

Development of methodologies based on HPLC and Raman spectroscopy for monitoring the stability of lovastatin in solid state in the presence of gallic acid.

Methodologies based on FT-Raman spectroscopy and HPLC were developed for monitoring the stability of lovastatin in the solid state in the presence of gallic acid, a natural antioxidant. A Raman calibration curve was constructed using the area of the strong but overlapping vibration mode of lovastatin at 1645 cm(-1) and of the gallic acid at 1595 cm(-1). Mixtures of the active ingredient with the antioxidant were heated in the presence of atmospheric air up to 120 degrees C. The molar ratios of lovastatin and gallic acid in the artificially oxidized mixtures were determined from their Raman spectra using the calibration curve. The results were compared to those obtained from the application of the HPLC methodology and found to match satisfactorily. The HPLC analysis was based on a reserved-phase Zorbax C(g), 10 microm (4.6mm x 25 cm i.d.) column, using a gradient elution program by varying the proportion of solvent A acetonitrile 100% to solvent B 0.1% v/v phosphoric acid, and a programmable diode array detection at 225 nm. The Raman methodology was simpler and non-destructive for the sample but yielded only molar ratios as opposed to the HPLC technique where the moles of the both ingredients were determined.

Anticholesteremic Agents↗

PubMed2006

Methodological quality and outcomes of studies addressing manual cervical spine examinations: a review.

The aims of this review were, first to rate the methodological quality of studies which investigate the reliability of manual tests for cervical spine dysfunctions by applying a new quality assessment tool; secondly to compare the outcomes of these studies. The literature search included databases of CINAHL, MEDLINE, AMED, AMI, and SPORT DISCUS, the Cochrane Library, the Physiotherapy Evidence Database (PEDro), the National Library of Medicine (PubMed), Factiva, the EBSCOT HOST Research Database, online journal databases of ELSEVIER Science periodicals, LIPPINCOTT WILLIAMS & WILKINS, ELSEVIER Science @ Direct, THIEME ONLINE, and BLACKWELL SYNERGY. The application of the Quality Assessment of Diagnostic Accuracy Studies tool (QUADAS) to the 15 studies which met the inclusion criteria showed methodological weaknesses such as not considering an independent reference standard, or a representative study population. The studies demonstrated methodological strength in describing selection criteria and in interpreting results. The studies' outcomes make the claim to be able to detect segmental cervical dysfunction based on a manual assessment only questionable. Further improvements in quality, uniform study designs, and a valid reference standard would be necessary in order to obtain more reliable data in the future.

Cervical Vertebrae↗

PubMed2006

Novel methodology to comprehensively assess retinal arteriolar vascular reactivity to hypercapnia.

PURPOSE: (1) Describe a new methodology that permits the comprehensive assessment of retinal arteriolar vascular reactivity in response to a sustained and stable hypercapnic stimulus. (2) Determine the magnitude of the vascular reactivity response of the retinal arterioles to hypercapnic provocation in healthy, young subjects. METHODOLOGY: Eleven healthy subjects of mean age 27 years (SD 3.43) participated in the study and one eye was randomly selected. A mask attached to a sequential rebreathing circuit, and connected to a gas delivery system, was fitted to the face. To establish baseline values, subjects breathed bottled air for 15 min and at least 6 blood flow measurements of the supero-temporal arteriole were acquired using the Canon Laser Blood Flowmeter (CLBF). Air flow was then decreased until a stable increase in fractional end-tidal CO(2) concentration (F(ET)CO(2)) of 10-15% was achieved. CLBF measurements were acquired every minute (minimum of 6 measurements) during the 20-minute period of elevated F(ET)CO(2). F(et)CO(2) was then reduced to baseline levels, and 6 further CLBF measurements were acquired. Respiratory rate, blood pressure, pulse rate and oxygen saturation were monitored continuously. RESULTS: Retinal arteriolar diameter, blood velocity and blood flow increased during hypercapnia relative to baseline (p=0.0045, p<0.0001 and p<0.0001, respectively). Group mean F(ET)CO(2) showed an increase of 12.0% (SD 3.6) relative to baseline (p<0.0001). CONCLUSIONS: This study describes a new methodology that permits the comprehensive assessment of retinal arteriolar vascular reactivity in response to a sustained and stable hypercapnic stimulus. Retinal arteriolar diameter, blood velocity and blood flow increased significantly in response to a hypercapnic provocation in young, healthy subjects.

Adult↗

PubMedDate not supplied

The use of focus group methodology in health disparities research.

Focus group methodology uses focused interviews to obtain information from individuals and interactions among individuals in a small group setting. In this article we share the insights we have gained from using focus group methodology in work with an under-served population of black menopausal women. This methodology holds promise for advancing our understanding of, and ultimately eliminating, health disparities. Included is a discussion of planning and facilitating the focus group, recruiting group members, collecting and analyzing the data and reporting the results. Throughout, we explain how we applied these principles and we conclude by sharing lessons learned from our study on menopause and midlife experiences in Black women.

Black or African American↗

PubMed2006

Individual patient's preferences for hypertension management: a Q-methodological approach.

OBJECTIVE: To systematically explore and elicit individual patient's preferences in the management of their hypertension using Q-methodology. METHODS: Using Q-methodology, 120 patients ranking 42 statements according to their agreement or disagreement when considering appropriate hypertension management. The statements were derived from an earlier qualitative study. Factor analysis of the data was undertaken using PQMethod software to determine if any patterns were discernible. RESULTS: Ninety-two patients clustered to five factors, which all varied in the degree of involvement patients had, or wished to have, in their hypertension management. The 42 patients who loaded to factor 1 considered that appropriate antihypertensive treatment involved leaving medical decisions to their GPs and trusting their judgement in such matters. The patients (n = 31) who positively loaded to factor 2 suggested that an autonomous relationship with their healthcare professional(s) was an important issue when considering treatment. CONCLUSION: It is concluded that this study has successfully used Q-methodology to systematically investigate people's subjectivity and developed a novel approach to elicit the views of individual patients, as well as explore and differentiate between groups of patients. PRACTICE IMPLICATIONS: The formation of true partnerships between patients and healthcare professionals which will enhance individual patients' ability to self-manage chronic disease.

Adult↗

PubMed2004

A structured methodology to calculate traffic emissions inventories for city centres.

This study presents a methodology to estimate traffic emissions inventories for the case of city centres. It deals with the problem in a structured manner, identifying the sources and the formats of the input data as well as labelling the steps needed to perform the calculation. It describes a method to calculate the total mileage driven around the city using the concept of mileage per zone. Although the methodology employs a classical approach through the use of emission factors developed for mean speeds, it also discusses the possibility of applying these factors to instantaneous speeds. Finally, the study focuses on the influence of two critical factors: time resolution and the estimate of the total mileage. In both cases, the results indicate that the assumptions made are adequate and yield accurate results. The methodology has been applied to the city of Madrid as an example.

Journal Article↗

PubMed2005

A methodology for the assessment of rehabilitation success of post mining landscapes--sediment and radionuclide transport at the former Nabarlek uranium mine, Northern Territory, Australia.

Protection of the environment post-mining is an important issue, especially where runoff and erosion can lead to undesirable material leaving post-mining landscapes and contaminating surrounding land and watercourses. Methods for assessment of the environmental impact and long-term behaviour of post-mining landforms based on scientific methodology are needed especially where field data are absent or poor. An appraisal of the former Nabarlek uranium mine was conducted to assess the site from a soil erosion perspective as part of an independent evaluation of overall rehabilitation success. Determination of the gross erosion occurring, sediment discharge to Cooper Creek and the resultant sediment associated radionuclide load in Cooper Creek were the primary objectives of the study. These objectives were achieved through the application of several models using parameter values collected from the site. The study found that the area containing the mill tailings repository is extremely stable and meets the guidelines established for long-term storage of uranium mill tailings. Most other areas on the site are stable; however there are some areas with a high sediment loss. Sediment concentration in Cooper Creek, which drains the site, was found to be within the Australian water quality guidelines for fresh water, however sediment concentrations in tributaries were found to exceed recommended levels. Radionuclide determinations on soil samples showed that the highest specific activities (Bq kg-1) were present on a small (0.44 ha) area with a relatively high erosion rate. This small area contributed the majority of the estimated flux to Cooper Creek of uranium-series radionuclides sorbed or structurally incorporated to eroded soil particles sourced from the mine site. This study provides a methodology for assessment of the erosional stability of such a landscape and consequent impact on water quality, using extensive field data and readily available and well known models and methodologies.

Environmental Monitoring↗

PubMed2005

An integrated modelling and multicriteria analysis approach to managing nitrate diffuse pollution: 1. Framework and methodology.

As trade-off relationships between the agronomy and the environment are common over land uses within a catchment, one of major concerns of catchment management plans is how to balance the trade-offs over land uses at the catchment-scale. In this two-part paper, an integrated modelling and multicriteria analysis (MCA) methodology is presented which can be used to evaluate a set of land use alternatives and to identify an 'ideal' compromise between economic return and environmental pollution. This 'ideal' compromise here is achieved by land use optimisation of which the objective is to minimise the environmental pollution (nitrate leaching rate) and to maximise the economic return (agronomic gross margin), considering both environmental and economic potential across the catchment in a site-specific manner. The suggested methodology can be used to produce a site-specifically optimised land use scenario that is an 'ideal' compromise between nitrate diffuse pollution and agronomy at the catchment-scales. Some issues on the actual application of the methodology are also discussed.

Agriculture↗

PubMed2004

Executive control of attention in sleep apnea patients: theoretical concepts and methodological considerations.

Sleep apnea patients' nocturnal breathing disturbances cause daytime sleepiness and cognitive impairments. Attentional capacity and vigilance deficits have often been observed. Moreover, some studies have suggested executive dysfunction, usually assumed to be related to (pre)frontal lobe dysfunction caused by intermittent hypoxemia. However, sleep disruption itself has a pervasive influence on cognitive function and affects not only underlying 'lower-level' processes such as arousal and alertness, but also 'higher-level' cognitive processes such as executive attention. This methodological caveat has not been fully taken into account in the sleep apnea literature. In order to be able to disentangle these cognitive processes on different levels, sound theoretical neurocognitive frameworks are needed to attain careful analyses and interpretations of neuropsychological data. Therefore, this paper firstly presents an overview of relevant theoretical concepts and models of arousal, attention, and executive function. Then, it is being argued that these theoretical considerations have important methodological implications. These methodological concerns are being addressed by specific experimental and statistical approaches, illustrated by some well-known neuropsychological tests. It can be concluded that the reported executive deficits in sleep apnea patients should be regarded as tentative, and that more case-controlled studies are needed using fine-grained analyses to parcel complex cognitive abilities into their subcomponents.

Arousal↗

PubMed2004

A methodological and substantive review of the evidence that schools cause pupils to smoke.

The objectives of this review were to examine whether smoking prevalence varies between schools independently of health promotion programmes and pupil composition, to show which school characteristics are responsible for this variation, and to examine the methodological adequacy of such studies. Searches for published studies were performed on medical, educational and social science databases, relevant articles' reference lists, and citation searches. Any study was included that described inter-school variation in smoking prevalence, or related such variation to school characteristics. A model relating pupil smoking to school, neighbourhood, and pupil characteristics unlikely and likely to be influenced by school was used to examine the adequacy of control of confounding by pupil composition. Data from studies were combined qualitatively considering methodological adequacy to examine the relation of smoking prevalence to school characteristics. Theoretical frameworks underpinning the choice of school characteristics and postulated relationships between these characteristics and smoking prevalence were described. There were large variations in smoking prevalence between ostensibly similar schools. Evidence that pupil composition did not cause this was weak, because all studies had methodological problems, including under control of relevant pupil compositional factors and over control of factors likely to represent the mechanism through which schools influence pupils' smoking. There was little evidence that elements of tobacco control policy other than bans and enforcement deterred smoking. Academic practice and school ethos were related to smoking. Academically selective schools did not influence smoking, once pupil composition was controlled. There was one study on neighbourhood influences, which were unrelated to smoking. Studies frequently offered little or no theoretical justification for associating school characteristics with smoking. Some aspects of school influence pupils' smoking, probably independently of pupil composition. However, under-control and over-control of confounding and lack of theoretical underpinning precludes definitive conclusions on how particular school characteristics influence pupils' smoking.

Adolescent↗

PubMed2005

A methodology for structural health monitoring with diffuse ultrasonic waves in the presence of temperature variations.

Diffuse ultrasonic waves for structural health monitoring offer the advantages of simplicity of signal generation and reception, sensitivity to damage, and large area coverage; however, there are the serious disadvantages of no accepted methodology for analyzing the complex recorded signals and sensitivity to environmental changes such as temperature and surface conditions. Presented here is a methodology for applying diffuse ultrasonic waves to the problem of detecting structural damage in the presence of unmeasured temperature changes. This methodology is based upon the prediction and observation that the first order effect of a temperature change on a diffuse ultrasonic wave is a time dilation or compression. A multi-step procedure is implemented to (1) record a set of baseline waveforms from the undamaged specimen at temperatures spanning the expected operating range, (2) select a waveform from the baseline set whose temperature is the closest to that of a subsequently measured signal, (3) adjust this baseline waveform to best match the signal, and (4) calculate an error parameter between the signal and the adjusted waveform and compare this parameter to a threshold to determine the structural status. This procedure is applied to experimental data from aluminum plate specimens with artificial flaws. Probability of detection and the minimum flaw size detected are presented as a function of the size of the baseline waveform set. It is shown that a probability of detection of over 95% can be achieved with a small number of baseline waveforms.

Environmental Monitoring↗

PubMed2005

Environmental diagnosis methodology for municipal waste landfills.

A large number of countries are involved in a process of transformation with regard to the management of municipal solid waste. This process is a consequence of environmental requirements that occasionally materialise in legislation, such as the European Council Directive 31/99/EC on waste release in the European Union. In some cases, the remediation of old landfills can be carried out in compliance with environmental requirements; in other cases, it is necessary to proceed with the closure of the landfill and to assimilate it into its own environment. In both cases, it is necessary to undertake a diagnosis and characterisation of the impacted areas in order to develop an adequate action plan. This study presents a new methodology by which environmental diagnosis of landfill sites may be carried out. The methodology involves the formulation of a series of environmental indeces which provide information concerning the potential environmental problems of the landfills and the particular impact on different environmental elements, as well as information related to location, design and operation. On the basis of these results, it would be possible to draw up action plans for the remediation or closure of the landfill site. By applying the methodology to several landfills in a specific area, it would be possible to prioritize the order of actions required.

Air↗

PubMed2004

An evaluation of benchmark dose methodology for non-cancer continuous-data health effects in animals due to exposures to dioxin (TCDD).

The U.S. Environmental Protection Agency (EPA) has conducted extensive reviews and analyses of health effects associated with exposures to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and related compounds. Because the carcinogenicity of TCDD has received considerable attention from EPA and others, this paper focuses on animal data for non-cancer health effects that sometimes appear to be almost as sensitive as cancer to TCDD exposures. Benchmark dose (BMD) methodology can be used to identify point-of-departure (POD) estimates for use in derivation of reference doses or evaluation of margins of exposure. However, selection of an appropriate BMD methodology for assessment of non-cancer data, which are usually continuous (non-quantal), needs to be considered. One option available for a benchmark dose is to use a small percentage change in the mean response relative to the estimated maximum effect of TCDD at large doses. The benchmark based on a change estimated to equal 1% of the estimated maximum change from background to the asymptotic response at large doses (denoted as the relative ED01) was used by EPA in a reassessment of TCDD health risks. A lower confidence limit (LED01) could serve as a point of departure for setting a reference dose (RfD). This is a somewhat arbitrary effect level, generally within the background range of variation among unexposed animals, with an unknown risk. An alternative approach is recommended in which the risk of abnormal levels can be estimated. For continuous-data effects, a low and/or high percentile (e.g., 1st and/or 99th) in unexposed control animals can be used to define abnormal (not necessarily adverse) levels. From a dose-response curve and the standard deviation, it is possible to estimate the excess risk (proportion) of animals with abnormal levels as a function of dose for normally distributed levels. With this approach, the risk-based benchmark dose (BMD01) represents the dose with an estimated excess risk of 1% of the animals in the abnormal range rather than an arbitrary change in the value of the measured endpoint. Values for the relative and risk-based benchmark doses are computed from published data for a variety of non-cancer health effects associated with exposure to TCDD. For the 30 cases investigated, the BMD01 tended to vary around the lowest experimental dose tested, whereas the relative ED01 tended to be about a factor of three below the lowest dose, and the BMD01 was more precisely estimated than the ED01 as reflected by narrower confidence intervals. The BMDL01 values were on average more than fivefold higher than the corresponding LED01 values. However, these values still provide a conservative assessment for POD assessment, because the BMDL01 tends to be about an order of magnitude lower (more conservative) than the no-observed-adverse-effect level. This analysis demonstrates the potential impact of alternative choices in benchmark dose methodology. In combination with selection of appropriate adverse health effect endpoint(s) and studies, use of the risk-based BMD results in identification of more valid and meaningful POD estimates for non-cancer effects compared to the use of the relative ED approach.

Animals↗

PubMed1998

Methodological advances and developments in the assessment of psychopathy.

The last decade has witnessed a number of significant methodological advances and developments in the assessment of psychopathy. The Psychopathy Checklist-Revised and the two-factor model of psychopathy have facilitated the assessment of psychopathy and clarified the differential correlates of the personality- and behavior-based operationalizations of this syndrome. Although preliminary evidence suggests that certain features of psychopathy may be underpinned by a latent taxon, the categorical versus dimensional status of psychopathy requires clarification. Researchers have accorded increasing attention to the assessment of psychopathy in non-criminal samples, although the construct of subclinical psychopathy remains controversial. Other recent methodological developments include: (a) the extension of the Five-Factor Model and other higher-order personality taxonomies to psychopathy; (b) development of a Q-sort methodology to permit the assessment of psychopathy by observers; (c) standardized assessment of psychopaths' interpersonal behaviors; (d) assessment of psychopathy in children; and (e) examination of gender, ethnic, and cross-cultural differences in psychopathy.

Adult↗