Publications by authors named "Antonio Villegas"

The age difference among individuals of the same group is known as Relative Age. Relative Age Effect refers to the consequences derived from it, such as delayed physical, cognitive and mental development of children born later in the year. The aim of this study was to observe the Relative Age Effect by analyzing players' dates of birth throughout three seasons in the two professional football competitions in Spain based on the game positions and the teams' classification at the end of the season.

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Stone consolidants have been widely used to protect historical monuments. Consolidants and hydrophobic formulations based on the use of tetraethoxysilane (TEOS) and alkylalkoxysilanes as precursors have been widely applied, despite their lack of solubility in water and requirement to be applied in organic media. In the search for a "greener" alternative based on silicon that has potential use in this field, the use of tetrakis(2-hydroxyethyl)silane (THEOS) and tris(2-hydroxyethyl)methyl silane (MeTHEOS) as precursors, due their high water solubility and stability, is proposed in this paper.

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The glycol alkoxysilanes, tetrakis(2-hydroxyethyl)silane (THEOS), and tris(2-hydroxyethyl)methyl silane (MeTHEOS) are water soluble derivatives of tetraethoxysilane (TEOS) and methyltriethoxysilane (MeTEOS) and precursors of the system silane-chitosan reviewed in this work. The glycol modified alkoxysilanes are obtained by transesterification reaction of TEOS or MeTEOS with ethylene glycol. The reaction evolution is monitored by Si NMR.

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Background: The prevalence of type 2 diabetes is increasing at an alarming rate in Latin America and in the Caribbean. We present evidence that a cost-effective and sustainable approach to lifestyle modification in underdeveloped countries can be implemented using community members as healthcare champions.

Methods: Of 222 community members screened in the impoverished community of Villa Juana, Santo Domingo, 69% had prediabetes or diabetes and 79 of these were enrolled.

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Positron emission tomography (PET) with (18)F-fluorodeoxyglucose (FDG) is a valuable tool for diagnosing and staging malignant lesions. The fusion of PET and computed tomography (CT) yields images that contain both metabolic and morphological information, which, taken together, have improved the diagnostic precision of PET in oncology. The main imaging modality for planning radiotherapy treatment is CT.

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