887 resultados para NEUTRON-CAPTURE ELEMENTS


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A label-free DNA aptamer-based impedance biosensor for the detection of E. coli outer membrane proteins (OMPs) was developed. Two single stranded DNA sequences were tested as recognition elements and compared. The aptamer capture probes were immobilized, with and without 6-mercapto-1-hexanol (MCH) on a gold electrode. Each step of the modification process was characterized by Faradaic impedance spectroscopy (FIS). A linear relationship between the electron-transfer resistance (Ret) and E. coli OMPs concentration was demonstrated in a dynamic detection range of 1 × 10−7–2 × 10−6 M. Moreover, the aptasensor showed selectivity despite the presence of other possible water contaminates and could be regenerated under low pH condition. The developed biosensor shows great potential to be incorporated in a biochip and used for in situ detection of E. coli OMPs in water samples.

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Gottfried Leibniz generalized the derivation and integration, extending the operators from integer up to real, or even complex, orders. It is presently recognized that the resulting models capture long term memory effects difficult to describe by classical tools. Leon Chua generalized the set of lumped electrical elements that provide the building blocks in mathematical models. His proposal of the memristor and of higher order elements broadened the scope of variables and relationships embedded in the development of models. This paper follows the two directions and proposes a new logical step, by generalizing the concept of junction. Classical junctions interconnect system elements using simple algebraic restrictions. Nevertheless, this simplistic approach may be misleading in the presence of unexpected dynamical phenomena and requires including additional “parasitic” elements. The novel γ-junction includes, as special cases, the standard series and parallel connections and allows a new degree of freedom when building models. The proposal motivates the search for experimental and real world manifestations of the abstract conjectures.

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Proceedings of the 13th International UFZ-Deltares Conference on Sustainable Use and Management of Soil, Sediment and Water Resources - 9–12 June 2015 • Copenhagen, Denmark

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Because of the scientific evidence showing that arsenic (As), cadmium (Cd), and nickel (Ni) are human genotoxic carcinogens, the European Union (EU) recently set target values for metal concentration in ambient air (As: 6 ng/m3, Cd: 5 ng/m3, Ni: 20 ng/m3). The aim of our study was to determine the concentration levels of these trace elements in Porto Metropolitan Area (PMA) in order to assess whether compliance was occurring with these new EU air quality standards. Fine (PM2.5) and inhalable (PM10) air particles were collected from October 2011 to July 2012 at two different (urban and suburban) locations in PMA. Samples were analyzed for trace elements content by inductively coupled plasma–mass spectrometry (ICP-MS). The study focused on determination of differences in trace elements concentration between the two sites, and between PM2.5 and PM10, in order to gather information regarding emission sources. Except for chromium (Cr), the concentration of all trace elements was higher at the urban site. However, results for As, Cd, Ni, and lead (Pb) were well below the EU limit/target values (As: 1.49 ± 0.71 ng/m3; Cd: 1.67 ± 0.92 ng/m3; Ni: 3.43 ± 3.23 ng/m3; Pb: 17.1 ± 10.1 ng/m3) in the worst-case scenario. Arsenic, Cd, Ni, Pb, antimony (Sb), selenium (Se), vanadium (V), and zinc (Zn) were predominantly associated to PM2.5, indicating that anthropogenic sources such as industry and road traffic are the main source of these elements. High enrichment factors (EF > 100) were obtained for As, Cd, Pb, Sb, Se, and Zn, further confirming their anthropogenic origin.

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The geographical distribution and intra-domiciliary capture of sylvatic triatomines in three districts of the province of La Convención, Cusco, Peru are presented. In the district of Vilcabamba, eight adults of Rhodnius pictipes and five adults of Panstrongylus geniculatus were found. In the district of Ocobamba, 19 adults, 14 nymphs, and eggs of P. rufotuberculatus were found. In the district of Echarate, six adults and 10 nymphs of Eratyrus mucronatus, an adult of R. pictipes and P. geniculatus, and a nymph of P. rufotuberculatus were also found. The geographical distribution of E. mucronatus has extended to Cusco. This is the first report in Peru of household colonization by this triatomine.

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Dissertação para obtenção do Grau de Mestre em Engenharia Mecânica

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PURPOSE: The Genous™ stent (GS) is designed to accelerate endothelization, which is potentially useful in the pro-thrombotic environment of ST-elevation acute myocardial infarction (STEMI). We aimed to evaluate the safety and effectiveness of the GS in the first year following primary percutaneous coronary intervention (PCI) and to compare our results with the few previously published studies. METHODS AND MATERIALS: All patients admitted to a single center due to STEMI that underwent primary PCI using exclusively GS, between May 2006 and January 2012, were enrolled. The primary study endpoints were major adverse cardiac events (MACEs), defined as the composite of cardiac death, acute myocardial infarction and target vessel revascularization, at one and 12months. RESULTS: In the cohort of 109 patients (73.4% male, 59 ±12years), 24.8% were diabetic. PCI was performed in 116 lesions with angiographic success in 99.1%, using 148 GS with median diameter of 3.00mm (2.50-4.00) and median length of 15mm (9-33). Cumulative MACEs were 2.8% at one month and 6.4% at 12months. Three stent thromboses (2.8%), all subacute, and one stent restenosis (0.9%) occurred. These accounted for the four target vessel revascularizations (3.7%). At 12months, 33.9% of patients were not on dual antiplatelet therapy. CONCLUSIONS: GS was safe and effective in the first year following primary PCI in STEMI, with an apparently safer profile comparing with the previously published data. SUMMARY: We report the safety and effectiveness of the Genous™ stent (GS) in the first year following primary percutaneous coronary intervention in ST-elevation acute myocardial infarction. A comprehensive review of the few studies that have been published on this subject was included and some suggest a less safe profile of the GS. Our results and the critical review included may add information and reinforce the safety and effectiveness of the GS in ST-elevation in acute myocardial infarction.

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Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.

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Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.

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AIMS: To evaluate the long-term clinical outcomes following percutaneous coronary intervention (PCI) with the Genous stent in an unselected population. METHODS: All patients admitted to a single center who underwent PCI using the GS exclusively, between May 2006 and May 2012, were enrolled, and a clinical follow-up of up to 60 months was carried out. The primary endpoint of major adverse cardiac event (MACE) rate was defined as the composite of cardiac death, acute myocardial infarction (AMI), and target lesion revascularization (TLR). RESULTS: Of the 450 patients included (75.1% male; 65.5 ± 11.7 years), 28.4% were diabetic and acute coronary syndrome was the reason for PCI in 76.4%. Angioplasty was performed in 524 lesions using 597 Genous stents, with angiographic success in 97.1%. At a median of 36 months of follow-up (range, 1-75 months), MACE, AMI, TLR, stent restenosis (SR), and stent thrombosis (ST) rates were 15.6%, 8.4%, 4.4%, 3.8%, and 2.2%, respectively. Between 12 and 24 months, the TLR, SR, and ST rates practically stabilized, up to 60 months. Bifurcation lesions were independently associated with MACE, TLR, and SR. CONCLUSION: This is the first study reporting clinical results with the Genous stent up to 60 months. The Genous stent was safe and effective in the long-term, in an unselected population.

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BACKGROUND & AIMS: Patients who underwent endoscopic gastrostomy (PEG) present protein-energy malnutrition, but little is known about Trace Elements (TE), Zinc (Zn), Copper (Cu), Selenium (Se), Iron (Fe), Chromium (Cr). Our aim was the evaluation of serum TE in patients who underwent PEG and its relationship with serum proteins, BMI and nature of underlying disorder. METHODS: A prospective observational study was performed collecting: patient's age, gender, underlying disorder, NRS-2002, BMI, serum albumin, transferrin and TE concentration. We used ferrozine colorimetric method for Fe; Inductively Coupled Plasma-Atomic Emission Spectroscopy for Zn/Cu; Furnace Atomic Absorption Spectroscopy for Se/Cr. The patients were divided into head and neck cancer (HNC) and neurological dysphagia (ND). RESULTS: 146 patients (89 males), 21-95 years: HNC-56; ND-90. Low BMI in 78. Low values mostly for Zn (n = 122) and Fe (n = 69), but less for Se (n = 31), Cu (n = 16), Cr (n = 7); low albumin in 77, low transferrin in 94 and 66 with both proteins low. Significant differences between the groups of underlying disease only for Zn (t140.326 = -2,642, p < 0.01) and a correlation between proteins and TE respectively albumin and Zn (r = 0.197, p = 0.025), and albumin and Fe (r = 0.415, p = 0.000). CONCLUSIONS: When gastrostomy was performed, patients display low serum TE namely Zn, but also Fe, less striking regarding others TE. It was related with prolonged fasting, whatever the underlying disease. Low proteins were associated with low TE. Teams taking care of PEG-patients should use Zn supplementation and include other TE evaluation as part of the nutritional assessment of PEG candidates.

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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

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Dissertação para obtenção do grau de Mestre em Engenharia Química e Bioquímica

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INTRODUCTION: The present study compares human landing catches of primary malaria vectors with two alternative methods of capture: the Shannon trap and the Mosquito magnet. METHODS: This study used regression models to adjust capture data to a negative binominal distribution. RESULTS: Capture numbers and relative percentages obtained from the three methods vary strongly between species. The highest overall captures were obtained for Anopheles triannulatus with captures for the Shannon trap and the Mosquito magnet measuring more than 330% higher than captures obtained by human landings. For Anopheles darlingi, captures by the Shannon trap and the Mosquito magnet were about 14% and 26% of human landing catches, respectively. Another species with malaria transmission potential that was not sampled by human landing captures weascaptured by the Shannon trap and the Mosquito magnet (Anopheles oswaldoi). Both alternative sampling techniques can predict the human landing of Anopheles triannulatus, but without proportionality. Models for Anopheles darlingi counts, after totaling daily captures, are significant and proportional, but prediction models are more reliable when using the Shannon trap compared with the Mosquito magnet captures. CONCLUSIONS: These alternative capture methods can be partially recommended for the substitution of human landing captures or, at least, as complementary forms of monitoring for malarial mosquitoes.