RESUMO
A characterization program has been developed at Hanford to image past leaks in and around the underground storage tank facilities. The program is based on electrical resistivity, a geophysical technique that maps the distribution of electrical properties of the subsurface. The method was shown to be immediately successful in open areas devoid of underground metallic infrastructure, due to the large contrast in material properties between the highly saline waste and the dry sandy host environment. The results in these areas, confirmed by a limited number of boreholes, demonstrate a tendency for the lateral extent of the underground waste plume to remain within the approximate footprint of the disposal facility. In infrastructure-rich areas, such as tank farms, the conventional application of electrical resistivity using small point-source surface electrodes initially presented a challenge for the resistivity method. The method was then adapted to directly use the buried infrastructure, specifically the steel-cased wells that surround the tanks, as "long" electrodes for both transmission of electrical current and measurements of voltage. Overcoming the drawbacks of the long electrode method has been the focus of our work over the past 7 years. The drawbacks include low vertical resolution and limited lateral coverage. The lateral coverage issue has been improved by supplementing the long electrodes with surface electrodes in areas devoid of infrastructure. The vertical resolution has been increased by developing borehole electrode arrays that can fit within the small-diameter drive casing of a direct push rig. The evolution of the program has led to some exceptional advances in the application of geophysical methods, including logistical deployment of the technology in hazardous areas, development of parallel processing resistivity inversion algorithms, and adapting the processing tools to accommodate electrodes of all shapes and locations. The program is accompanied by a full set of quality assurance procedures that cover the layout of sensors, measurement strategies, and software enhancements while insuring the integrity of stored data. The data have been shown to be useful in identifying previously unknown contaminant sources and defining the footprint of precipitation recharge barriers to retard the movement of existing contamination.
Assuntos
Monitoramento Ambiental/métodos , Poluentes do Solo/análise , Eletrodos , Eliminação de Resíduos/métodos , Tecnologia de Sensoriamento RemotoRESUMO
CONTEXT: The role of multiparametric magnetic resonance imaging (mp-MRI) during active surveillance (AS) of prostate cancer needs evaluation. It remains unclear whether mp-MRI can replace prostate biopsies completely during AS. OBJECTIVE: To evaluate the diagnostic performance of mp-MRI for disease progression in men on AS for prostate cancer. EVIDENCE ACQUISITION: This systematic review was performed in accordance with the Cochrane Handbook and the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). Cross-sectional studies that evaluate the diagnostic performance of mp-MRI (index test) for disease progression compared with systematic and targeted prostate/template biopsies or a composite of this (reference standard) were included. A meta-analysis was performed using STATA with "metandi" and "midas" commands. EVIDENCE SYNTHESIS: Seven studies with 800 patients were included in this systematic review. The pooled pathological progression rate was 27%. The pooled sensitivity and specificity of mp-MRI for disease progression were 0.61 (95% confidence interval [CI]: 0.46-0.74) and 0.78 (95% CI: 0.54-0.91), respectively. Adjusting for a prevalence of disease progression of 30% results in a positive predictive value of 0.43 (95% CI: 0.39-0.46) and a negative predictive value of 0.81 (95% CI: 0.78-0.84). Significant heterogeneity was observed. The meta-regression analysis did not demonstrate any significant outliers. CONCLUSIONS: It is not possible to supplant prostate biopsies with mp-MRI in AS protocols with the current level of evidence. There is significant institutional variation in the diagnostic performance of mp-MRI during AS. Institutions must internally audit the diagnostic performance of mp-MRI in the AS setting. AS protocols must be based on local diagnostic performance, rather than on international AS protocols that may have limited applicability at individual settings. PATIENT SUMMARY: In this review, we explored the accuracy of multiparametric magnetic resonance imaging in diagnosing disease progression for patients who were enrolled in active surveillance programmes for prostate cancer.
Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata , Estudos Transversais , Testes Diagnósticos de Rotina , Humanos , Biópsia Guiada por Imagem , Masculino , Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico por imagem , Conduta ExpectanteRESUMO
As sporting challenge at the elite level becomes ever harder, maximizing effectiveness of the talent development pathway is crucial. Reflecting this need, this paper describes the development of the Talent Development Environment Questionnaire, which has been designed to facilitate the development of sporting potential to world-class standard. The questionnaire measures the experiences of developing athletes in relation to empirically identified "key features" of effective talent development environments. The first phase involved the generation of questionnaire items with clear content and face validity. The second phase explored the factor structure and reliability. This was carried out with 590 developing athletes through application of exploratory factor analysis with oblique rotation, principal axis factoring extraction and cronbach alpha tests. This yielded a 59-item, seven-factor structure with good internal consistency (0.616-0.978). The Talent Development Environment Questionnaire appears to be a promising psychometric instrument that can potentially be useful for education and formative review in applied settings, and as a measurement tool in talent development research.
Assuntos
Aptidão , Atletas , Esportes , Inquéritos e Questionários , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto JovemRESUMO
Percutaneous renal biopsy is a valuable diagnostic approach. While commonly safe, it is not without risk and the most feared vascular complications include hemorrhage, pseudoaneurysm, and arteriovenous fistula formation. We report a case of acute hemorrhage after renal biopsy that was immediately identified by ultrasonography and successfully treated with percutaneous perirenal thrombin injection. This technique may prove a useful addition to the armamentarium of any operator performing renal biopsies.
Assuntos
Hemorragia/tratamento farmacológico , Biópsia Guiada por Imagem/efeitos adversos , Nefropatias/tratamento farmacológico , Nefropatias/patologia , Trombina/administração & dosagem , Idoso , Hemorragia/diagnóstico por imagem , Hemorragia/etiologia , Humanos , Injeções , Nefropatias/diagnóstico por imagem , Masculino , Resultado do Tratamento , Ultrassonografia de Intervenção/métodosRESUMO
Virtual reality (VR) provides a three-dimensional computer representation of a real world or imaginary space through which a person can navigate and interact with objects to carry out specific tasks. One novel application of VR technology is in rehabilitation following stroke, particularly of the upper limb. This paper describes the development of a VR system for use in this field. This system gives the user the ability to interact with objects by touching, grasping and moving their upper limb.
Assuntos
Modalidades de Fisioterapia/instrumentação , Reabilitação do Acidente Vascular Cerebral , Extremidade Superior/fisiopatologia , Interface Usuário-Computador , Tecnologia Biomédica/instrumentação , Tecnologia Biomédica/métodos , Simulação por Computador , Humanos , Acidente Vascular Cerebral/fisiopatologia , Terapia Assistida por Computador/instrumentação , Terapia Assistida por Computador/métodosRESUMO
This systematic review examined the physical and cognitive effects of physically based interactive computer games (ICGs) in older adults. Literature searching was carried out from January 2000 to June 2011. Eligible studies were trials involving older adults (>65 years) describing the effects of ICGs with a physical component (aerobic, strength, balance, flexibility) on physical or cognitive outcomes. Secondary outcomes included adverse effects, compliance, and enjoyment. Twelve trials met the inclusion criteria. ICG interventions varied in terms of software, game type, and nature of the computer interaction. Although there was preliminary evidence that ICG is a safe and effective exercise intervention for older adults, the dearth of high-quality evidence limits this finding. No major adverse effects were reported and two studies reported minor events. ICG could be improved further by tailoring interventions for older adults; in particular, they should aim to optimize participant safety, motivation, and enjoyment for this population.