805 research outputs found
Cambios en el uso del preservativo en una cohorte de prostitutas
ResumenObjetivoDescribir los cambios en el uso del preservativo en una cohorte de mujeres que ejercen la prostitución en Alicante y analizar los factores que se relacionan con los cambios en esta práctica preventiva.MétodosSe han usado los datos de un estudio prospectivo que incluyó a las mujeres dedicadas a la prostitución que acudieron al Centro de Información y Prevención de Sida (CIPS) de Alicante desde 1986 a 1996. Se estimó la frecuencia en el uso del preservativo con los clientes en la primera y última visita al centro, se valoró el cambio entre las dos visitas y los factores asociados a ellos. Se realizaron dos análisis de regresión logística para determinar la asociación entre el cambio positivo o negativo y las variables explicativas.ResultadosLa prevalencia de uso del preservativo en la última visita fue mayor que en la primera (83,9% frente al 69,2%; p < 0,001). Entre las prostitutas que trabajan en contactos se incrementa más de cinco veces el uso del preservativo que entre las que lo hacen en los clubs y en la calle. Las que tienen mayor tiempo de seguimiento son las que tienen una mayor prevalencia en el uso del preservativo al final del seguimiento (odds ratio ajustada > 6 años frente a < de un año = 7,61; intervalo de confianza [IC] del 95%: 2,2-26,0).ConclusiónEste estudio ha puesto en evidencia un incremento en la frecuencia del uso del preservativo y la baja frecuencia de su abandono en una cohorte de prostitutas a lo largo de 10 años. En un futuro será necesario adaptar esta estrategia preventiva a las nuevas formas de prostitución menos estables y al incremento de inmigrantes, factores que motivan una menor asistencia y adhesión a centros de prevención.SummaryObjetiveTo describe changes in condom use among prostitutes enrolled in a prospective cohort study in Alicante (Spain), and to identify those factors associated with changes in this behaviour.MethodsData from this study come from a prospective cohort study of women working at prostitution enrolled in a center for AIDS preventive at Alicante from 1986 to 1996. The proportion of condom use by prostitutes with their clients was recorded during the first visit and the last one, and changes in condom use were estimated as the difference between them. Two logistic regression analyses were done to identify those factors associated with positive or negative changes in condom use.ResultsA statistically significant increase in the prevalence of condom use was observed between the first, 69,2%, and the last visit, 83,9% (p < 0,001). Prostitutes working private increased the condom use more than five time than those working in clubs or at the street. The higher the follow-up time the higher the prevalence of condom user, OR > 6 years = 7,6 (95% CI: 2,2-26,0). No variable was associated with a negative change in condom use.ConclusionThis study shows an overall increase of condom use in a cohort of prostitutes after 10 years of follow-up. Relapse in risk behavior has been infrequent. In the future, preventive strategies to increase the use of condoms among prostitutes should be adapted to the new forms of sexual commerce
Las peroxidasas y la conversión del ácido 1-aminociclopropano-1-carboxílico en etileno
In this paper the role of peroxidases in the last step of the ethylene biosynthesis pathway, the conversion of 1-aminocyclopropane- 1-carboxylic acid, is discussed.<br><br>En el trabajo se discute el papel de las peroxidasas en el último paso de la ruta de biosíntesis del etileno, la conversión del ácido 1-aminociclopropano-1-carboxílico en etileno
Las peroxidasas y la conversión del ácido 1-aminociclopropano-1-carboxílico en etileno
In this paper the role of peroxidases in the last step of the ethylene biosynthesis pathway, the conversion of 1-aminocyclopropane- 1-carboxylic acid, is discussed.En el trabajo se discute el papel de las peroxidasas en el último paso de la ruta de biosíntesis del etileno, la conversión del ácido 1-aminociclopropano-1-carboxílico en etileno
Green Production of Anionic Surfactant Obtained from Pea Protein
A pea protein isolate was hydrolyzed by a double enzyme treatment method in order to obtain short peptide sequences used as raw materials to produce lipopeptides-based surfactants. Pea protein hydrolysates were prepared using the combination of Alcalase and Flavourzyme. The influence of the process variables was studied to optimize the proteolytic degradation to high degrees of hydrolysis. The average peptide chain lengths were obtained at 3–5 amino acid units after a hydrolysis of 30 min with the mixture of enzymes. Then, N-acylation in water, in presence of acid chloride (C12 and C16), carried out with a conversion rate of amine functions of 90%, allowed to obtain anionic surfactant mixtures (lipopeptides and sodium fatty acids). These two steps were performed in water, in continuous and did not generate any waste. This process was therefore in line with green chemistry principles. The surface activities (CMC, foaming and emulsifying properties) of these mixtures were also studied. These formulations obtained from natural renewable resources and the reactions done under environmental respect, could replace petrochemical based surfactants for some applications
Nutritional and functional characteristics of Erophaca baetica seeds, a legume endemic to the Mediterranean region
<i>Erophaca baetica</i> is a legume endemic to the Mediterranean region. Although the fruits and seeds are large, the presence of the “locoism” which produces the alkaloid, swainsonine has prevented its use as animal feed or for human nutrition. Their protein content and chromatographic profile, amino acid composition, fatty acid composition, and polyphenol contents have been determined in order to explore the potential of the <i>E. baetica</i> seeds as a source of dietary protein with functional components. The protein content was found to be 36% (w/w), and an amino acid analysis revealed a deficiency in sulphur amino acids, tryptophane, and lysine. The low lysine content is probably due to the abundance of alkaloids metabolically derived from this amino acid. Oleic and linoleic acids are the major fatty acids in the seeds. The antioxidant activity of polyphenol extracts was higher than the activity of the polyphenols extracted from most edible legume seeds. Hence, <i>E. baetica</i> seeds represent a promising source of functional and nutritional components on the condition that the anti-nutritional alkaloids are previously removed.<br><br><i>Erophaca baetica</i> es una leguminosa endémica de la región mediterránea. Aunque los frutos y las semillas son grandes, la presencia del alcaloide swainsonina causante de locoismo, ha impedido su uso como alimento para animales o para nutrición humana. El contenido proteico y su perfil cromatográfico, la composición de aminoácidos, de ácidos grasos, y contenido de polifenoles se han determinado con el fin de explorar el potencial de las semillas de <i>E. baetica</i> como una fuente de proteínas y de componentes funcionales de la dieta. El contenido de proteínas es del 36% (w / w), y el análisis de aminoácidos reveló deficiencia en aminoácidos azufrados, triptófano y lisina. El contenido de lisina bajo es probablemente debido a la abundancia de alcaloides metabólicamente derivados de este aminoácido. Los ácidos oleicos y linoleico son los principales ácidos grasos en las semillas. La actividad antioxidante de los extractos de polifenoles fue mayor que la actividad de los polifenoles extraídos de la mayoría de las semillas de leguminosas comestibles. Por lo tanto, las semillas de <i>E. baetica</i> representan una fuente interesante de componentes funcionales y nutricionales con la condición de que los alcaloides antinutricionales sean quitados antes
Relation between metallicities and spectral energy distributions of Herbig Ae/Be stars. A potential link with planet formation
(Abridged) The stellar metallicity, [M/H], may have important implications
for planet formation. In particular, Kama et al. proposed that the deficit of
refractory elements in the surfaces of some Herbig Ae/Be stars (HAeBes) may be
linked to the presence of disk cavities likely caused by Jovian planets that
trap the metal-rich content. This work aims to provide a robust test on the
previous proposal by analyzing the largest sample of HAeBes with homogeneously
derived [M/H] values, stellar, and circumstellar properties. [M/H] values of 67
HAeBes were derived based on observed spectra and Kurucz synthetic models.
Statistical analyses were carried out aiming to test the potential relation
between [M/H] and the group I sources from the spectral energy distribution
(SED) classification by Meeus et al., associated to the presence of cavities
potentially carved by giant planets. Our study robustly confirms that group I
sources tend to have a lower [M/H] than that of group II HAeBes. A similar
analysis involving SED-based transitional disks does not reveal such a
relation, indicating that not all processes capable of creating dust holes have
an effect on the stellar abundances. We also show that the observed [M/H]
differences are not driven by environmental effects. Finally, group I sources
tend to have stronger (sub-) mm continuum emission presumably related to the
presence of giant planets. Indeed, literature results indicate that disk
substructures probably associated to their presence are up to ten times more
frequent in group I HAeBes. We provide indirect evidences suggesting that giant
planets are more frequent around group I/low [M/H] stars than around the rest
of the HAeBes. However, the direct test requires multiple detections of forming
planets in their disks, so far limited to the candidate around the metal
depleted ([M/H] = -0.35 +- 0.25) group I HAeBe star AB Aur.Comment: 16 pages, 10 figures, 2 tables. Accepted in A&
Calidad nutricional del aceite de semilla de trece especies Asphodeline (Xanthorrhoeaceae) procedentes de Turquía
The fatty acid composition of the seed oil from 13 Turkish Asphodeline species was analyzed. The seed oil content ranged between 0.9% and 4.6%, and included 26 different fatty acids from C12:0to C22:5. The most abundant saturated, monounsaturated, and polyunsaturated fatty acids were C16:0 (5.7% to 23.7% of their total fatty acid content), C18:1ω9 (11.3% to 30.3%), and C18:2ω6 (49.2% to 66.1%). A. tenuior subsp. tenuiflora, which had the highest content of unsaturated fatty acids, also had the best fatty acid profile from a nutritional point of view. Asphodeline seed oil composition was similar to that of local, related vegetables such as onion seeds. Asphodeline species, which are most frequently grown to use the leaves in salads, may also be a good source of seed oil with good nutritional properties. Results of a cluster analysis using data on the fatty acid composition are consistent with the taxonomic classification of genus Asphodeline.Se ha analizado la composición en ácidos grasos del aceite de las semillas de 13 especies de Asphodeline de Turquía. El contenido en aceite de las semillas osciló entre el 0.9% y el 4.6% e incluyó 26 ácidos grasos distintos entre C12:0y C22:5. Los ácidos grasos saturados, monoinsaturados y poliinsaturados más abundantes fueron C16:0 (5.7% a 23.7%), C18:1ω9 (11.3% a 30.3%) y C18:2ω6 (49.2% a 66.1%). A. tenuior subsp. tenuiflora, que presentó el contenido más alto en ácidos grasos insaturados, también tenía el mejor perfil en ácidos grasos desde un punto de vista nutricional. La composición del aceite de las semillas de Asphodeline fue similar a la de vegetales relacionados como la cebolla. Asphodeline, cuyas hojas son consumidas en ensaladas, puede representar también una buena fuente de aceite de las semillas con buenas propiedades nutricionales. Los resultados del análisis de grupos usando los datos de la composición en ácidos grasos son consistentes con la clasificación taxonómica del género Asphodeline
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