Data Analysis of the Water and Scintillator Phases of SNO+ : from Solar Neutrino Measurements to Double Beta Decay Sensitivity Studies

SNO+ is a leading liquid scintillator experiment for neutrino physics, with the ultimate goal of conducting a low background search for 0ѵꞵꞵ decay using 1300 kg of 130Te. The observation of this lepton-number-violating nuclear transition would provide fundamental insights regarding the neutrino mass and nature, opening doors to physics beyond the Standard Model. The success of this search relies on a complete understanding of the backgrounds contaminating the 0ѵꞵꞵ region-of-interest, and an accurate model of the energy response of the detector. Both are addressed continuously during three different stages of the experiment’s operations – water, scintillator and Te-loaded phases. This thesis presents the analysis of data taken during the water and scintillator phases of the SNO+ experiment. Optical calibration data taken with a deployed source during the water phase allowed to measure for the first time in situ key optical parameters for the detector model, which will be common to all phases. The initial liquid scintillator data, taken during a 7 month transition period when the detector was half-filled with 365 tonnes of liquid scintillator on top of water, was used to characterize the intrinsic background contaminants in the scintillator. The background model was validated with a target-out double beta decay analysis, which tested for any unexpected background sources or leakage within the expected 0ѵꞵꞵ decay region-of-interest. Moreover, these data allowed the first physics measurement using scintillator in SNO+ – a measurement of the 8B solar neutrino flux, Փ8B =6.534 (+26.11%)/(-22.39%) (stat.) (+11.38%)/(-9.64%) (syst.) X 106 cm-2 s-1 with an exposure of 11.2 kt day, compatible with previous measurements by other experiments. Based on the best knowledge of the backgrounds in the detector and of its energy response, a Monte Carlo based analysis was performed in order to evaluate the expected precision for the measurement of the 2ѵββ decay of 130Te, one of the major intrinsic background expected for the 0ѵββ search. Due to the large detector mass and isotope loading, SNO+ will achieve exposures competitive with other double beta decay experiments and statistical uncertainties well below 1% with a few months of data. It is expected that the future half-life measurement will be limited by systematic uncertainties due to energy scale and background correlations, which could be on the order of 5%. These will have to be accurately determined and minimized using calibrations after the tellurium is loaded

Radon concentration assessment in water sources of public drinking of Covilhã's county, Portugal

Radon, the heaviest of the noble gases on the periodic table of elements, is a natural radioactive element that can be found on water, soils and rocks. The main goal of this work is to present an evaluation of radon concentration on samples of water, used for human consumption, collected on uranium-rich granitic rock areas. Once the geological features of the sampling region evidence the presence of this natural radionuclides, their slow dissolution steadily increases concentration in ground water. Although, the most important contribution of natural radiation, for most populations, is from inhaled radon (generic term used commonly to refer to the isotope 222Rn), in some circumstances, exposure to natural radionuclides, through drinking water, could exceed acceptable levels, and also present a hazard. Despite the fact that radon can be reduced if the water is boiled, this gas, dissolved in ground water, can be released into the air during household activities such as showering, dishwashing and laundry. So, the short lived radon decay products will contribute to increase the number of those which are present in particles suspended in the indoor air and can be accumulated up to dangerous concentrations. Once the radon progeny emits highly ionizing alpha-radiation, they may cause substantial health damage after long-term exposure. Radon concentration measurements were performed on thirty three samples collected from water wells at different depths and types of aquifers, at Covilhã's County, Portugal with the radon gas analyser DURRIDGE RAD7. Twenty three, of the total of water samples collected, gave, values over 100 Bq/L, being that 1690 Bq/L was the highest measured value.info:eu-repo/semantics/publishedVersio

DOE: high-pressure processing as a pre-treatment for production of raw ewe milk-cheese

info:eu-repo/semantics/publishedVersio

The role of transaction costs in the delivering of urban infrastructure services: an overview of brazilian and portuguese municipalities

The present paper explores the different options for delivering public services by Portuguese and Brazilian municipalities. With reduction of human and financial resources and increase in demand, large municipalities need efficient arrangements to deliver public services. In fact, the conditions for providing these services influence the quality of life, the economic development and are directly related to the capacity of institutions to find the most appropriate governance mechanisms. In this context, the use of Transaction Costs Theory (TCT), specifically economic and political costs, reveals an appropriated tool to understand the ways how public services can be delivered. Existing research and theory point out several studies around the world that analyze how different governance mechanism’s choice (hierarchy, market and network) can be explained based on TCT. This paper contributes to expand this topic to Brazilian’s municipalities context, due to the lack of studies in this country. Contrariwise, there are more studies about Portuguese’s municipalities, but as a dynamic process, it’s becomes interesting update such studies in order to expand the existing database. In this sense we addressed a preliminary step whose objective is to identify the different options for public service delivery, finding similarities and differences in these two countries, following a qualitative approach. As results, we find that governance mechanisms adopted by two countries are very similar. The differences result from regional level in Brazil that allows recourse to state's business sector, as opposed to Portugal. In turn, Portuguese municipalities have several options that result from municipal associations, options that are more limited in Brazilian case.info:eu-repo/semantics/publishedVersio

Are CSR leaders less prone to engage in impression management?

This study examines the readability of corporate communication in the CEO letters included in the corporate social responsibility (CSR) reports presented by the firms that comprise the S&P 500 Index. These documents were content analyzed through the use of an automated algorithm provided by Readable.IO. Using a frame of analysis based on the social psychology theory of impression management, we studied the impression management tactics used. The main findings suggest that leading CSR companies (those listed in the Dow Jones Sustainability Index) present more readable CSR information in terms of comprehension and extension. These companies disclose CSR information generally in a positive way. However, these disclosure patterns are mediated by the “goal relevance of the impressions” and the “value of desired goals” related to the impression management tactics usedinfo:eu-repo/semantics/publishedVersio

Bioactivity of Monoterpene Alcohols as an Indicator of Biopesticidal Essential Oils against the Root Knot Nematode Meloidogyne ethiopica

The application of pesticides remains one of the most efficient control methods for phytophagous parasites in crops. Essential oils (EOs) are complex mixtures of highly active compounds that can be used as biopesticides against plant parasitic nematodes. In the present work, the antinematodal activity of the monoterpene alcohols geraniol, linalool, menthol or  -terpineol, which are generally found in high amounts in EOs of some aromatic and medicinal plants, was analyzed on the root knot nematode Meloidogyne ethiopica. Geraniol showed intense and lasting antinematodal activity, suggesting that EOs rich in this compound can be used in the development of nematicidal biopesticides to integrate sustainable pest management strategies against this pest

Optimization of raw ewes’ milk high-pressure pre-treatment for improved production of raw milk cheese

Serra da Estrela protected designation of origin (PDO) cheese is manufactured with raw milk from Bordaleira and/or Churra Mondegueira da Serra da Estrela sheep breeds. Several socioenvironmental shortcomings have reduced production capacity; hence, treatments that may contribute to its efficient transformation into cheese are welcome. High-pressure processing (HPP) milk pre-treatment may contribute to a cheese yield increment, yet optimization of processing conditions is warranted. An initial wide-scope screening experiment allowed for pinpointing pressure intensity, holding time under pressure and time after HPP as the most important factors influencing curd yield. Based on this, a more targeted screening experiment allowed for selecting the range of experimental conditions to be used for an experimental design study that revealed an HPP treatment at 121 MPa for 30 min as the optimum for milk processing to improve curd yield (>9%) and effectively maintain the beneficial cheese microbiota; the optimum was validated in a final experimental framework.info:eu-repo/semantics/publishedVersio