Publications by authors named "Antonio Rojas"

Unmanned aerial vehicles are clear candidates to benefit from wireless power transfer, as it can facilitate their charging process and even allow them to charge autonomously. One common approach when designing a wireless power transfer (WPT) system is to incorporate ferromagnetic material to guide the magnetic field and improve system efficiency. However, a complex optimization calculation must be carried out to determine the positions and size of the ferromagnetic material and thereby restrict the additional weight imposed.

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This study aimed to analyze the relationship among different evaluative reactions of the intergroup attitudes and contact in Spanish adolescents evaluating different ethnic minorities and in immigrant-background adolescents evaluating Spanish youth. This study was based on psychosocial models of great impact in the study of intergroup relations such as the Stereotype Content Model and the Behaviors from Intergroup Affect and Stereotypes Map, and incorporated a new approach to the study of attitudes: psychological networks. In total, 1122 Spanish adolescents and 683 adolescents with an immigrant background (Moroccan, Romanian or Ecuadorian origin) participated in the study, aged from 12 to 19 years.

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Glycolaldehyde (GAld) is a C water-soluble aldehyde produced during the atmospheric oxidation of isoprene and many other species and is commonly found in cloudwater. Previous work has established that glycolaldehyde evaporates more readily from drying aerosol droplets containing ammonium sulfate (AS) than does glyoxal, methylglyoxal, or hydroxyacetone, which implies that it does not oligomerize as quickly as these other species. Here, we report NMR measurements of glycolaldehyde's aqueous-phase reactions with AS, methylamine, and glycine.

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In general, the Attitudes toward Sexual Behaviors (ASB) or Sexual Attitudes measures have not been focused in the conjoint measurement of persons and items in the same construct, and have not reflected the new sexual behaviors neither the context where sexual behaviors take place. The purpose of this study was to provide evidence of the validity of a theoretical model for the measurement of ASB using the person-item map provided by a Rasch model. The theoretical model explicitly defines the ASB construct and makes a proposal where the items are intensity-ordered.

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The UPPS Impulsive Behaviour Scale (with five dimensions of impulsive behaviour) is being widely used. One of the handicaps of this instrument is its relatively long administration time. This has led to the development of a short version: SUPPS-P.

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Stereotype dimensions-competence, morality and sociability-are fundamental to studying the perception of other groups. These dimensions have shown moderate/high positive correlations with each other that do not reflect the theoretical expectations. The explanation for this (e.

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Objective: The aim of this study was to analyze the impact of psychiatric comorbidity and severity of dependence on health-related quality of life (HRQoL).

Methods: One hundred and ninety-eight substance use disorder (SUD) patients were recruited from an outpatient center that provides treatment for SUD. The International Personality Disorder Examination Screening Questionnaire (IPDE-SQ), Mini International Neuropsychiatric Interview (MINI), Substance Dependence Severity Scale (SDSS) and Health-Related Quality of Life for Drug Abusers test (HRQoLDA test) were administered.

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Background: In the field of drug and alcohol abuse, health-related quality of life (HRQoL) has been used as an important clinical and research outcome. The aim of this study was to establish score linkages (concordance) among three HRQoL assessment tools: WHOQOL-BREF, DUQOL and HRQOLDA scores, applying a Rasch-based common person equating procedure.

Methods: One hundred and twenty one adults were recruited from inpatient and outpatient treatment facilities in Sydney West Area Health Service.

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Objective: Therapeutic success in the treatment of alcohol use disorders highly depends on an appropriate diagnosis. The Substance Dependence Severity Scale –SDSS- is a scale that assesses substance dependence in dimensional terms and that follows the diagnostic criteria established by the international classification systems. The aim of this study is to provide validity evidence for the severity dimension of the alcohol dependence scale of the SDSS comparing it with the Mini International Neuropsychiatric Interview –MINI-, and others variables related to substance use included in the EuropASI.

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Purpose: The purpose of this study was to estimate the reliability and provide evidence for the validity of the Spanish version of the Substance Dependence Severity Scale (SDSS).

Methods: A total of 211 substance abusers recruited at a public center that provides treatment for substance-related disorders in an outpatient setting were assessed. Reliability was estimated by Cronbach's α and test-retest.

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The main goal of this study was to identify acculturation preference profiles using cluster analysis in public and private areas of culture in the host and immigrant populations, and to find out the relationship between these profiles and prejudice levels. Four hundred and ninety-nine Spaniards and 500 Romanians participated in a survey. The sampling of Spaniards was multistage random and the sampling of Romanians was by quota.

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The demand for light beers has led brewers to innovate by developing light beer. However, these products are not widely accepted in Europe compared to North America and Australasia because of their lack of fullness in the taste and low bitterness compared with conventional beer. The lower levels of some important compounds, present in light beer, can explain these features since they are responsible for the characteristics of the beer.

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Unlabelled: We evaluate the elimination of the microscopic stage of conventional xenodiagnosis (XD) to optimize the parasitological diagnosis of Trypanosoma cruzi in chronic Chagas disease. To this purpose we applied under informed consent two XD cages to 150 Chilean chronic chagasic patients. The fecal samples (FS) of the triatomines at 30, 60 and 90 days post feeding were divided into two parts: in one a microscopic search for mobile trypomastigote and/or epimastigote forms was performed.

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The Substance Dependence Severity Scale -SDSS- is one of the few scales that assesses substance dependence and abuse according DSM criteria in dimensional terms. Several studies have provided evidence of psychometric validity and reliability in its English version, but there is no Spanish version available. The aim of this work was to describe the adaptation process of the English version of the SDSS into Spanish, and provide preliminary results on its reliability and validity evidence.

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The detoxification capacity of the clinoptilolite modification KLS-10-MA used as food additive in small mammals, chronically lead-exposed, was proven for the first time. The modified clinoptilolite was prepared based on natural Bulgarian clinoptilolite deposits. As a powder, it was mechanically mixed at 12.

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The aim of this work is to show evidence of the validity of the Health-Related Quality of Life for Drug Abusers Test (HRQoLDA Test). This test was developed to measure specific HRQoL for drugs abusers, within the theoretical addiction framework of the biaxial model. The sample comprised 138 patients diagnosed with opiate drug dependence.

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Since vanadyl sulphate has demonstrated insulin-like effects on glucose metabolism in animal and human trials, and organic vanadium complexes are better absorbed by the intestinal tract than vanadyl species, in this work the complexation of oxovanadium(IV) with 2-acetyl-1,3-cyclopentanedione is studied. Kinetic and equilibria in aqueous 1:1 chelation are investigated spectrophotometrically in aqueous solution at 25 degrees C. The mechanism proposed to account for the kinetic data involves a reversible pathway where VO(+2) reacts with the enolate ion of the ligand.

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Europe has been influenced by both intra- and intercontinental migrations. Since the Iberian peninsula was a refuge during the Last Glacial Maximum, demographic factors associated with contraction, isolation, subsequent expansion and gene flow episodes have contributed complexity to its population history. In this work, we analysed 26 Y-chromosome biallelic markers in 568 chromosomes from 11 different Iberian population groups and compared them to published data on the Basques and Catalans to gain insight into the paternal gene pool of these populations and find out to what extent major demographic processes account for their genetic structure.

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The presence of Trypanosoma cruzi in chronic chagasic patients with negative xenodiagnosis (XD) after 6 years following completion of therapy with either itraconazole or allopurinol was assessed by polymerase chain reaction (PCR) and hybridization assays. A 330-bp DNA fragment amplified from the hypervariable regions of T. cruzi kinetoplastid minicircles was hybridized with total 32P-labeled kinetoplast DNA as probes.

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Compensated frameshift mutation is a modification of the reading frame of a gene that takes place by way of various molecular events. It appears to be a widespread event that is only observed when homologous amino acid and nucleodotide sequences are compared. To identify these mutation events, the sequence analysis rationale was based on the search for short regions that would have much lower degrees of conservation in protein, but not in DNA, in well-conserved beta-glucosidase families.

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Background: Malaria was restricted to the I Region of Chile, being Anopheles pseudopunctipennis the only vector species. In 1936 the parasitosis affected more than 50% of the population and 62.4% of military recruits, proceeding from Southern regions became infected.

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