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This Letter reports on a search for nu(mu) --> nu(e) transitions by the MINOS experiment based on a 3.14x10(20) protons-on-target exposure in the Fermilab NuMI beam. We observe 35 events in the Far Detector with a background of 27+/-5(stat)+/-2(syst) events predicted by the measurements in the Near Detector. If interpreted in terms of nu(mu) --> nu(e) oscillations, this 1.5sigma excess of events is consistent with sin2(2theta(13)) comparable to the CHOOZ limit when |Delta m2|=2.43x10(-3) eV2 and sin2(2theta(23))=1.0 are assumed.
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A wide range of waste characterization methods are available, each developed for a specific purpose such as determining compost stability, or for landfill acceptance criteria. Here test methods have been evaluated for the purpose of assessing waste treatment process performance and monitoring the diversion of biodegradable municipal waste (BMW) from landfill. The suitability factors include the timescale of the method, applicability to a wide range of materials and ability to indicate the long-term biodegradability of organic waste samples. The anaerobic test methods, whilst producing reliable results, take at least several weeks to complete, therefore, not allowing for regular routine analysis often required for diversion assessments. Short-term tests are required which can correlate with, and, therefore, estimate, values obtained from long-term anaerobic methods. Aerobic test methods were found to offer a significantly improved timescale compared with anaerobic test methods; however, they have limitations due to not measuring the full extent of sample biodegradability. No single test method was found to be completely sufficient for routine biodegradability analysis suitable for monitoring the BMW diversion from landfill. Potential areas for further research include spectrographic FT-IR or enzyme-based approaches such as the ECD or EHT methods.
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Monitoreo del Ambiente/métodos , Eliminación de Residuos , Aerobiosis , Anaerobiosis , Biodegradación Ambiental , Ciudades , Temperatura , Factores de TiempoRESUMEN
This report describes an investigation into the bioavailability and fate of trace metals and their subsequent impact on important soil microbiological functions such as nitrification, denitrification and methane oxidation in low and high Cu containing soils in the presence and absence of residual organic matter from sewage sludge additions made 10 years earlier. The soils being studied are part of long term sewage sludge trials and include a low Cu soil (13.3 mg Cu/kg soil, 4.18 LOI %), left un-amended to serve as a control soil, soil amended with a high Cu sewage sludge (278.3 mg Cu/kg soil, 6.52 LOI %) and soil amended with a low Cu sewage sludge (46.3 mg Cu/kg soil, 6.18 LOI %). Soil was also amended with inorganic metal salts (273.4 mg Cu/kg soil, 4.52 LOI %) to further investigate the impact of Cu in the absence of additional organic matter contained in applied sewage sludge. Data from the first two years of a project are presented which has included field-based studies at long term sewage sludge trials based in Watlington, Oxford, UK and laboratory based studies at the Institute of Grassland & Environmental Research, North Wyke, Devon, UK.
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Cobre , Fertilizantes , Aguas del Alcantarillado , Microbiología del Suelo , Dióxido de Carbono/metabolismo , Metano/metabolismo , Óxido Nitroso/metabolismo , SueloRESUMEN
Exposure to ionizing radiation increases the risk of myelodysplastic syndromes (MDS) and myeloproliferative neoplasms (MPN), but such risks are not known in well-differentiated thyroid cancer (WDTC) patients treated with radioactive iodine (RAI). A total of 148 215 WDTC patients were identified from Surveillance, Epidemiology and End Results registries between 1973 and 2014, of whom 54% underwent definitive thyroidectomy and 46% received adjuvant RAI. With a median follow-up of 6.6 years, 77 and 66 WDTC patients developed MDS and MPN, respectively. Excess absolute risks for MDS and MPN from RAI treatment when compared to background rates in the US population were 6.6 and 8.1 cases per 100 000 person-years, respectively. Compared to background population rates, relative risks of developing MDS (3.85 (95% confidence interval, 1.7-7.6); P=0.0005) and MPN (3.13 (1.1-6.8); P=0.012) were significantly elevated in the second and third year following adjuvant RAI therapy, but not after thyroidectomy alone. The increased risk was significantly associated with WDTC size ⩾2 cm or regional disease. Development of MDS was associated with shorter median overall survival in WDTC survivors (10.3 vs 22.5 years; P<0.001). These data suggest that RAI treatment for WDTC is associated with increased risk of MDS with short latency and poor survival.
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Isótopos de Yodo/efectos adversos , Leucemia Mielógena Crónica BCR-ABL Positiva/etiología , Trastornos Mieloproliferativos/etiología , Neoplasias de la Tiroides/radioterapia , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Factores de Riesgo , Tiroidectomía/métodos , Adulto JovenRESUMEN
Use of a pilot-scale fixed-film bioreactor was investigated for remediation of bromate contamination within groundwater. Bromate reduction with stoichiometric production of bromide was observed, providing supporting evidence for complete reduction of bromate with no production of stable intermediates. Reduction of 87-90% bromate from an influent concentration of 1.1 mg L(-1) was observed with retention times of 40-80 h. Lower retention times led to decreases in bromate reduction capability, with 11.5% removal at a 10 h retention time. Nitrate reduction of 76-99% from a 30.7 mg L(-1) as NO(3)(-) influent was observed at retention times of 10-80 h, although an increase in nitrite production to 2.7 mg L(-1) occurred with a 10 h retention time. Backwashing was not required, with the large plastic packing media able to accommodate biomass accumulation without decreases in operational efficiency. This study has provided proof of concept and demonstrated the potential of biological bromate reduction by fixed-film processes for remediation of a bromate contaminated groundwater source.
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Reactores Biológicos , Bromatos/aislamiento & purificación , Contaminantes del Suelo/aislamiento & purificación , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/aislamiento & purificación , Abastecimiento de Agua , Biomasa , Bromatos/metabolismo , Nitratos/aislamiento & purificación , Nitratos/metabolismo , Gestión de Riesgos , Contaminantes del Suelo/metabolismo , Factores de Tiempo , Contaminantes Químicos del Agua/metabolismoRESUMEN
A potential remediation technique for groundwater contaminated by bromate has been investigated, utilising biological bromate reduction to bromide by augmentation of indigenous microbial populations. This technique, involving addition of a carbon source to contaminated groundwater, is being developed as an ex-situ methodology analogous to commercial denitrification systems, but may also have in-situ applications. Trials have focussed on a laboratory-scale anaerobic suspended growth chemostat system, investigating glucose addition to real groundwater supplies. Steady states for a range of glucose and bromate concentrations demonstrated bromate reduction up to 700 microgl(-1) (50% of 1400 microgl(-1) influent) with glucose excess (above 52 mgl(-1)), but specific reduction rates (up to 2.83 micromol Br.g dry wt(-1) hr(-1) for 1400 microgl(-1) bromate influent) were low compared to denitrification (up to 305 micromol N g dry wt(-1) hr(-1)). More recent enrichment trials have demonstrated reduction of 32 mgl(-1) bromate within a 40 hour residence time with specific reduction rates of up to 160.48 micromol Br.g dry wt(-1) hr(-1), suggesting the presence of high rate bromate reducing bacterial strains.
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Reactores Biológicos , Bromatos/metabolismo , Contaminación del Agua/prevención & control , Bacterias Anaerobias , Hidrógeno/análisis , Hidrógeno/química , Oxidación-Reducción , Contaminantes del Suelo/aislamiento & purificación , Solubilidad , Contaminantes del Agua/aislamiento & purificaciónRESUMEN
Drug treatment maintenance among a group of 206 hypertensive persons was examined in relation to their health beliefs, knowledge about hypertension, barriers to receiving medical care, health status, and personal characteristics. The data came from a cross-sectional survey of approximately 800 adults living in Detroit, Mich., which included blood pressure measurements of respondents. Treatment maintenance was defined as continuing to take antihypertensive medication following a diagnosis of hypertension. Twenty-one percent of the 206 hypertensives interviewed reported discontinuing drug treatment for their high blood pressure without being advised by a physician to do so. The only factor that distinguished drop-outs from nondrops was the respondents' perception of their health status; the poorer a person perceived his or her health to be, the more likely the person was to remain in treatment. Among persons who dropped out of drug treatment, the most common reason given for discontinuing was that they felt well without the medicine. Given the asymptomatic nature of hypertension, it is suggested that many of those who stop taking medication do so because they see no need to continue therapy. The findings from this study point out the need for providers to emphasize to their hypertensive patients the reasons for continuing on treatment even when they feel well.
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Actitud Frente a la Salud , Hipertensión/psicología , Cooperación del Paciente , Negro o Afroamericano , Estudios Transversales , Recolección de Datos , Femenino , Humanos , Hipertensión/tratamiento farmacológico , Masculino , Michigan , Persona de Mediana Edad , Población UrbanaRESUMEN
A laboratory scale reactor operated as a single sludge, denitrification-nitrification bioreactor (DNB), was fed a synthetic wastewater. The effect of the C/N ratio of the influent on the structure of beta-proteobacterial autotrophic ammonia-oxidizing bacterial (AOB) communities was determined by DGGE analysis of 16S rRNA gene fragments amplified using a range of AOB-selective primers. Fluorescence in situ hybridisation (FISH) was used to determine quantitative changes in the AOB communities. When operated at a C/N ratio of 2 the DNB was effective in nitrogen removal and nitrification was measured at approximately 1.0 mg NH4+-N/g dry wt/h. Altering the C/N ratio to 5 resulted in a 50% reduction in nitrification rates. Nitrification was restored to its original level when the C/N ratio was returned to 2. AOB were detected by DGGE analysis of samples from the DNB under all operating conditions but the changes in C/N ratio and nitrification rates were accompanied by changes in the community structure of the AOB. However, quantitative FISH analysis indicated that beta-proteobacterial AOB were only present in high numbers (ca. 10(8) cells/ml) under the original operating conditions with a C/N ratio of 2. Beta-proteobacterial AOB could not be detected by FISH when the C/N ratio was 5. When nitrification activity was restored by returning the C/N ratio to 2, beta-proteobacterial AOB were still not detected and it is likely that either beta-proteobacterial AOB were not responsible for ammonia oxidation or that beta-proteobacterial AOB that did not contain the target sites for the range of 4 AOB selective probes used, were present in the reactor.
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Amoníaco/metabolismo , Reactores Biológicos , Nitrógeno/metabolismo , Amoníaco/química , Carbono/análisis , Hibridación Fluorescente in Situ , Nitrógeno/análisis , Oxidación-Reducción , Proteobacteria/aislamiento & purificación , Proteobacteria/fisiología , ARN Ribosómico/análisis , Eliminación de Residuos LíquidosRESUMEN
PURPOSE: Auto-contouring of daily kV conebeam CTs (kVCBCT) is critical for online adaptive radiotherapy. We surveyed a set of geometric and dosimetric measures to determine which best assess the suitability of kVCBCT contouring algorithms for use in prostate region adaptive planning. METHODS: Six patients with daily kVCBCT undergoing IMRT of the prostate to 78 Gy were selected. Dose was recalculated with patient density forced to water. Contours were generated on nine kVCBCT for each patient using ABAS (Elekta Ltd.) and also by a physician. The prostate mean dose, D100, D98, where determined and V70 (% and cc) and mean dose for the bladder and rectum for both physician and auto contours. The Dice's Coefficient (DC) was calculated between auto and physician contours, as well as a restricted DC (rDC) which combines geometric and dosimetric information by comparing only the volume within a high dose region. RESULTS: Prostate accuracy can only be discerned with D100, additionally there is no correlation (R2=0.036) between D100 and DC. For all organs, mean dose does not reflect contour suitability. There is large variation in V70 (% and cc) for rectum and bladder, implying V70 is a sensitive indicator of contour suitability. There is however no correlation of V70 with DC. A dose region (>57 Gy) to calculate rDC was chosen to provided optimal correlation (R2>0.81) to V70 (% and cc, rectum and bladder). CONCLUSIONS: V70 for rectum and bladder shows the most sensitivity to contour suitability, by concentrating on where accuracy is most vital. Prostate contouring is less critical due to treatment margins, D100 provides the most discerning metric. DC and mean dose are not useable. In lieu of V70, rDC could be used. The rDC can be approximated by limiting to within 2-3 cm of the prostate contour, alleviating the need to calculate dose. A research version of ABAS was provided by Elekta.
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This paper presents a study to evaluate the recently developed enzymatic hydrolysis test (EHT) through its repeated application to a waste treatment process. A single waste treatment facility, involving a biodrying process, has been monitored using three different methods to assess the biodegradable content of the organic waste fractions. These test methods were the anaerobic BMc, aerobic DR4 and the EHT, which is a method based on the enzymatic hydrolysis of the cellulosic content of waste materials. The input municipal solid waste (MSW) and the output solid recovered fuel (SRF) and organic fines streams were sampled over a period of nine months from a single mechanical biological treatment (MBT) facility. The EHT was applied to each stream following grinding to <10 mm and <2 mm, in order to investigate the effect of particle size on the release of dissolved organic carbon (DOC) from enzyme hydrolysis. The output organic fines were found to more biodegradable than the MSW input and SRF output samples in each of the test methods, significantly (p<0.05) for the EHT and DR4 methods, on the basis of DOC released and oxygen consumed, respectively. The variation between sample replicates for the EHT was higher where sample sizes of <2 mm were analysed compared to sizes of <10 mm, and the DOC release at each phase of the EHT was observed to be higher when using particle sizes of <2 mm. Despite this, additional sample grinding from the <10 mm to a smaller particle size of <2 mm is not sufficiently beneficial to the analysis of organic waste fractions in the EHT method. Finally, it was concluded that as similar trends were observed for each test method, this trial confirms that EHT has the potential to be deployed as a practical operational biodegradability monitoring tool.
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Monitoreo del Ambiente/métodos , Enzimas/metabolismo , Eliminación de Residuos/métodos , Aerobiosis , Biodegradación Ambiental , Carbono/metabolismo , Ciudades , Inglaterra , Enzimas/química , Hidrólisis , Compuestos Orgánicos/metabolismo , Oxígeno/metabolismoRESUMEN
This Letter reports new results from the MINOS experiment based on a two-year exposure to muon neutrinos from the Fermilab NuMI beam. Our data are consistent with quantum-mechanical oscillations of neutrino flavor with mass splitting |Deltam2| = (2.43+/-0.13) x 10(-3) eV2 (68% C.L.) and mixing angle sin2(2theta) > 0.90 (90% C.L.). Our data disfavor two alternative explanations for the disappearance of neutrinos in flight: namely, neutrino decays into lighter particles and quantum decoherence of neutrinos, at the 3.7 and 5.7 standard-deviation levels, respectively.
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We report the first detailed comparisons of the rates and spectra of neutral-current neutrino interactions at two widely separated locations. A depletion in the rate at the far site would indicate mixing between nu(mu) and a sterile particle. No anomalous depletion in the reconstructed energy spectrum is observed. Assuming oscillations occur at a single mass-squared splitting, a fit to the neutral- and charged-current energy spectra limits the fraction of nu(mu) oscillating to a sterile neutrino to be below 0.68 at 90% confidence level. A less stringent limit due to a possible contribution to the measured neutral-current event rate at the far site from nu(e) appearance at the current experimental limit is also presented.