La adolescencia: retos para la investigación y para la sociedad europea de cara al sigol XXI

A lo largo de la última década, la adolescencia ha sido un tema dediscusión política en distintos espacios europeos al más alto nivel. En unasociedad aceleradamente cambiante se percibe que la adecuada socializaciónde las generaciones más jóvenes constituye un reto socio-históricoque nos afecta a todos. Los cambios en que estamos sumergidos son tanplurales (demográficos, sociales, tecnológicos, económicos, políticos,etc.) que generan un amplísimo frente de nuevos dilemas éticos. La opiniónde los ciudadanos de la Unión Europea se muestra preocupada pornuevos valores y destaca la preferencia por la responsabilidad en coherenciacon dicha situación cambiante. Todo este macrocontexto psicosocialviene planteando nuevos retos teóricos y de investigación a la comunidadcientífica. De hecho las ciencias humanas y sociales han empezadoa desarrollar nuevas líneas de investigación para comprender mejor lasnuevas relaciones entre adultos y adolescentes y las nuevas culturas queemergen entre estos últimos, impulsadas por nuevas aspiraciones socialescompartidas por grupos más o menos amplios de la población joven. Eldesarrollo de técnicas e instrumentos que nos permitan comprender mejorla perspectiva del adolescente se hace más evidente si analizamos su relacióncon las nuevas tecnologías de la información y la comunicación. Dichastecnologías comportan nuevos riesgos, pero también nuevas oportunidades,entre las que destaca la posibilidad de establecer nuevas formasde relación. La motivación que muestran los más jóvenes por las nuevastecnologías constituye un gran reto a los investigadores aplicados parasugerir formas de maximizar las potencialidades latentes

Análisis psicométrico de la escala multidimensional de autoconcepto AF5 en una muestra de adolescentes y adultos de Cataluña

Psychometric analysis of the AF5 multidimensional scale of self-concept in a sample of adolescents and adults in Catalonia. The aim of this study is to carry out a psychometric study of the AF5 scale in a sample of 4.825 Catalan subjects from 11 to 63 years-old. They are students from secondary compulsory education (ESO), from high school, middle-level vocational training (CFGM) and from the university. Using a principal component analysis (PCA) the theoretical validity of the components is established and the reliability of the instrument is also analyzed. Differential analyses are performed by gender and normative group using a 2 6 factorial design. The normative group variable includes the different levels classifi ed into 6 sub-groups: university, post-compulsory secondary education (high school and CFGM), 4th of ESO, 3rd of ESO, 2nd of ESO and 1st of ESO. The results indicate that the reliability of the Catalan version of the scale is similar to the original scale. The factorial structure also fi ts with the original model established beforehand. Signifi cant differences by normative group in the four components of self-concept explored (social, family, academic/occupational and physical) are observed. By gender, signifi cant differences appear in the component of physical self-concept, academic and social but not in the family component

Habilidades de cognición social en niños y niñas con el síndrome de Down: resultados de un estudio preliminar

The understanding of false belief is one of the most important milestones in the development of social cognition in children. Many studies have been conducted on this kind of cognition in children with a typical development. Despite being a key point for improving their welfare and quality of life, there are few studies in children with Down's syndrome. The aim of the present work is to carry out an in-depth study of social cognition in children with Down's syndrome. For this purpose, we used 6 tasks, with 3 levels of difficulty, in a group of 9 children aged between 4 and 14 years. Six of these children had a genetic diagnosis of Down's syndrome. The results of our research corroborate previous studies suggesting difficulties in the development of social cognition in children with Down's syndrome, and more specifically in tasks involving false beliefs

Determinación de vitamina C, compuestos fenólicos totales y actividad antioxidante de frutas de guayaba (Psidium guajava L.) cultivadas en Colombia

Some physicochemical parameters, vitamin C, total phenolic compounds and antioxidant activity (AA) measured by ABTS, FRAP and DPPH methods were determinated in four different varieties of ripe guava produced in Colombia. Samples were statistically similar in their titratable acidity. Soluble solids were statistically similar and higher in "Pear", "Pink Regional", and "White Regional", but lower in "Apple" guavas. Vitamin C was statistically lower in "Pear" guava. Phenolics, ABTS-, FRAP-, and DPPH-AA were statistically lower in "Apple" guava if compared in wet basis. "Pink Regional" and "White Regional" contained the highest levels in vitamin C, phenolics and antioxidant activity.

Aplicación de una lengua electrónica voltamétrica para la clasificación de vinos y estudio de correlación con la caracterización química y sensorial

This paper presents the analytical application of a novel electronic tongue based on voltammetric sensors array. This device was used in the classification of wines aged in barrels of different origins and toasting levels. Furthermore, a study of correlation between the response of the electronic tongue and the sensory and chemical characterization of samples was carried out. The results were evaluated by applying both principal component analysis and cluster analysis. The samples were clearly classified. Their distribution showed a high correspondence degree with the characteristics of the analyzed wines, it also showed similarity with the classification obtained from organoleptic analysis.

Preconcentración y atomización con tubo en la llama para la determinación de Cadmio en agua de mar

A flow injection on-line pre-concentration system coupled to thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS) for cadmium determination at sub μg L-1 levels in seawater samples was developed. The on-line system was evaluated by analysing cadmium containing in a synthetic seawater matrix (2.5% m/v NaCl, 0.5% m/v MgCl2 and 0.8% m/v CaCl2). A sample volume of 2 mL allows determining Cd with a detection limits of 30 ng L-1 (3* σblank/slope), pre-concentration factor of 34 and repeatability of 1,8% (calculated as RSD, N=8 and containing 200 ng L-1 of Cd ).

Determinación simultánea de Cr, Ni y V en orina mediante et aas

A procedure for the simultaneous determination of Cr, Ni, and V in urine by electrothermal atomic absorption spectrometry (ET AAS) was optimized by factorial design, and performed at a pyrolysis and atomization temperatures of 1300 and 2500 ºC, respectively, using 15 µg de Mg(NO3)2 as chemical modifier. Characteristics mass of 14, 6 and 220 ρg and detection limits of the method of 0.07, 0.38 and 0.75 µg L-1 were obtained for Cr, Ni and V respectively. The methodology was validated using a Liphochek Urine Metals Control sample (Bio-Rad) (P=0.05). The methodology was applied to samples of voluntary Venezuelan people, not environmentally exposed to specific emissions, and results ranging from < LOD-1.1 and 1.3-3.3 µg L-1 was observed for Cr and V, respectively, and not detectable levels for Ni.

Economic analysis of cashew early dwarf Crop BRS - 189 depending on water levels and doses of potassium fertilization

Water and fertilizer among the production factors are the elements that most restrict the production of cashew. The precise amount of these factors is essential to the success of the crop yield. This research aimed to determine the best factor-product ratio and analyze technical and economic indicators, of productivity of the cashew clone BRS 189 (Anacardium occidentale) to production factors water and potassium. The experiment was conducted from May 2009 to December 2009 in an experimental area of 56.0 m x 112.0 m in the irrigated Curu - Pentecoste, located in the municipality of Pentecoste, Ceará, Brazil. Production factors water (W) and potassium (K) were the independent variables and productivity (Y), the dependent variable. Ten statistical models that have proven satisfactory for obtaining production function were tested. The marginal rate of substitution was obtained through the ratio of the potassium marginal physical product and the water marginal physical product. The most suited model to the conditions of the experiment was the quadratic polynomial without intercept and interaction. Considering that the price of the water was 0.10 R$ mm -1, the price of the potassium 2.19 R$ kg -1 and the price of the cashew 0.60 R$ kg-1, the amounts of water and K2O to obtain the maximum net income were 6,349.1 L plant-1 of water and 128.7 g plant -1year, -1 respectively. Substituting the values obtained in the production function, the maximum net income was achieved with a yield of 7,496.8 kg ha-1 of cashew.

Fe y esperanza : women's road to leadership and ministry in the Lutheran church of El Salvador 1952-2009

The Lutheran Church of El Salvador made a decision, in 1986, to open the ministry to women. How was it possible in the midst of a Latin American macho culture and after having been influenced by the theologically conservative, North American mission work? This research examines the kinds of internal and external factors which led women to leadership and ministry, and the context in which this development occurred. The roles of women have been scrutinised during several time periods. During 1952-1974 the focus was on women as missionary wives and fundadoras (founding mothers). Women’s roles as laywomen grew in 1975-1985. After the outburst of the civil war in 1980, women advanced to lay leaders. The ministry was opened for women and the first deacon pastors were installed in 1986 and the first presbyter pastors were ordained in 1994. In 2009, more women than ever were working in different levels – from laywomen to leaders – in the Lutheran Church of El Salvador. The research shows that the reasons for the development and changes concerning women’s positions and roles lie in the impact of significant individuals, liberation theology, the feminist and women’s movement, civil war and the theology of life.

Respuestas morfológicas y anatómicas de Tessaria absinthioides (Hook. et Arn.) DC. a la salinidad

T. absinthioides, Inuleae, Compositae, is a weedy species that is spreading in the irrigation area of the Colorado River, Argentina. This species can be found in normal and saline soils. Morphological and anatomical variables were measured with two salts, sodium chloride and sodium sulfate, with three levels of osmotic potential -0.4, -0.8 and -1.5 MPa, in hydroponic culture, using Hoagland solution as the cultivation media. The total diameter of the roots of plants growing in Na2SO4 and NaCl increased when the osmotic potential was -0.4 MPa. In plants growing in NaCl this may have resulted from the increase in the size of the cortical cells and in plants growing in Na2SO4, the diameter increased may be due to an increase in the cambial activity. The number and length of shoot internodes decreased with increasing salinity, even though this was not statistically significant. In comparison to the control, the total diameter of the shoot increased at -0.4 MPa and decreased with the reduction of the osmotic potential. In comparison to the control, the length of the leaves decreased at -0.4 MPa and the leaves width increased at the same concentration. The palisade parenchyma appeared less developed in saline conditions. In comparison to the control, the number of hairs increased at -0.4 MPa. T. absinthioides acts as a semihalophytic species, according to the salt ranks it tolerates. The mechanisms of adaptation to saline conditions are succulence in root and stunted growth if the salt in the media is NaCl, and the production of haloxeromorphic characters if the salt in the media is Na2 SO4

Cytokine profile and nitric oxide levels in sera from patients with brucellosis

The aims of this study were to investigate the serum levels of some cytokines [tumor necrosis factor-alpha (TNF-alpha), interleukin 1ß (IL-1ß), IL-2R, IL-6, and IL-8] and nitric oxide (NO) levels in patients with untreated brucellosis and to test the correlation of these parameters with each other. The study was conducted on 67 subjects, 37 patients with brucellosis and 30 healthy individuals with no history of Brucella infection. Brucellosis was identified by a positive blood culture and/or increased Brucella antibodies in serological tests in addition to compatible clinical symptoms. Cytokine profile analysis was performed by the immulite chemiluminescent enzyme immunometric assay whose inter- and intra-assay coefficients of variance were 2.6-3.6 and 4.4-8.5%, respectively. The levels of nitrites/nitrates, which are representative of NO levels, were measured by the Griess method. Patients with brucellosis had significantly elevated serum levels of nitrites/nitrates, IL-2R, IL-6 and IL-8 (mean ± SD, 102.8 ± 23.8 µmol/l, 806.1 ± 58.5 U/ml, 21.1 ± 2.3 pg/ml, and 8.8 ± 1.6 pg/ml, respectively) compared to healthy controls, whereas TNF-alpha and IL-1ß levels were unchanged. No statistically significant correlation was detected between any of the studied cytokine levels and nitrate/nitrite concentrations according to Pearson's linear correlation test. We conclude that only IL-6, IL-8 and IL-2R are elevated in brucellosis and the extent of elevation depends on the severity and clinical pattern of the disease. Moderate elevation in serum NO was comparable to that observed in previous studies. This explains the absence or very rare occurrence of septic shock in brucellosis.

Lipoprotein lipase PvuII polymorphism is associated with variations in serum lipid levels in non-diabetic pregnant women

The aim of the present study was to determine if there is an association between the single nucleotide polymorphisms (SNPs) of the lipoprotein lipase (LPL) and apolipoprotein E (apo E) genes and the serum lipid profile in pregnancy and puerperium. Non-diabetic women of European descent in the third semester of pregnancy (N = 120) were selected. Those with diseases or other condition that could modify their lipid profile were excluded from the study (N = 32). Serum lipids were measured by routine laboratory procedures and genomic DNA was extracted by a salting out method. LPL (PvuII and HindIII) and apo E (HhaI) SNPs were detected by the polymerase chain reaction and restriction fragment length polymorphism. Categorical and continuous variables were compared by the chi-square test and Student t-test or ANOVA, respectively. Women carrying the LPL P1P1 genotype had higher serum LDL cholesterol (N = 21; 155 ± 45 mg/dL) than women carrying the P1P2/P2P2 genotypes (N = 67; 133 ± 45 mg/dL; P = 0.032). During the puerperium period, serum levels of triglycerides and VLDL cholesterol were significantly reduced in women carrying the P1P1 (73%, P = 0.006) and P1P2 (51%, P = 0.002) genotypes but not in women carrying the P2P2 genotype (23%, P > 0.05). On the other hand, serum concentrations of lipids did not differ between the LPL HindIII and apo E genotypes during pregnancy and after delivery. We conclude that LPL PvuII SNP is associated with variations in serum lipids during pregnancy and the puerperal period in non-diabetic women.

Amniotic fluid amino acid levels in non-immune hydrops fetalis: a case-control study

In a prospective case-control study, we compared the amniotic fluid amino acid levels in non-immune hydrops fetalis (NIHF) and normal fetuses. Eighty fetuses underwent amniocentesis for different reasons at the prenatal diagnosis unit of the Department of Obstetrics and Gynecology, Faculty of Medicine, Dicle University. Forty of these fetuses were diagnosed with NIHF. The study included 40 women each in the NIHF (mean age: 27.69 ± 4.56 years) and control (27.52 ± 5.49 years) groups, who had abnormal double- or triple-screening test values with normal fetuses with gestational ages of 23.26 ± 1.98 and 23.68 ± 1.49 weeks at the time of sample collection, respectively. Amniotic fluid amino acid concentrations (intra-assay variation: 2.26-7.85%; interassay variation: 3.45-8.22%) were measured using EZ:faast kits (EZ:faast GC/FID free (physiological) amino acid kit; Phenomenex, USA) by gas chromatography. The standard for quantitation was a mixture of free amino acids from Phenomenex. The levels of 21 amino acids were measured. The mean phosphoserine and serine levels were significantly lower in the NIHF group, while the taurine, α-aminoadipic acid (aaa), glycine, cysteine, NH4, and arginine (Arg) levels were significantly higher compared to control. Significant risk variables for the NIHF group and odds coefficients were obtained using a binary logistic regression method. The respective odds ratios and 95% confidence intervals for the risk variables phosphoserine, taurine, aaa, Arg, and NH4 were 3.31 (1.84-5.97), 2.45 (1.56-3.86), 1.78 (1.18-2.68), 2.18 (1.56-3.04), and 2.41 (1.66-3.49), respectively. The significant difference between NIHF and control fetuses suggests that the amniotic fluid levels of some amino acids may be useful for the diagnosis of NIHF.

Changes in tau phosphorylation levels in the hippocampus and frontal cortex following chronic stress

Studies have indicated that early-life or early-onset depression is associated with a 2- to 4-fold increased risk of developing Alzheimers disease (AD). In AD, aggregation of an abnormally phosphorylated form of the tau protein may be a key pathological event. Tau is known to play a major role in promoting microtubule assembly and stabilization, and in maintaining the normal morphology of neurons. Several studies have reported that stress may induce tau phosphorylation. The main aim of the present study was to investigate possible alterations in the tau protein in the hippocampus and frontal cortex of 32 male Sprague-Dawley rats exposed to chronic unpredictable mild stress (CUMS) and then re-exposed to CUMS to mimic depression and the recurrence of depression, respectively, in humans. We evaluated the effects of CUMS, fluoxetine, and CUMS re-exposure on tau and phospho-tau. Our results showed that a single exposure to CUMS caused a significant reduction in sucrose preference, indicating a state of anhedonia. The change in behavior was accompanied by specific alterations in phospho-tau protein levels, but fluoxetine treatment reversed the CUMS-induced impairments. Moreover, changes in sucrose preference and phospho-tau were more pronounced in rats re-exposed to CUMS than in those subjected to a single exposure. Our results suggest that changes in tau phosphorylation may contribute to the link between depression and AD.

Elevated levels of plasma osteoprotegerin are associated with all-cause mortality risk and atherosclerosis in patients with stages 3 to 5 chronic kidney disease

Osteoprotegerin (OPG) regulates bone mass by inhibiting osteoclast differentiation and activation, and plays a role in vascular calcification. We evaluated the relationship between osteoprotegerin levels and inflammatory markers, atherosclerosis, and mortality in patients with stages 3-5 chronic kidney disease. A total of 145 subjects (median age 61 years, 61% men; 36 patients on hemodialysis, 55 patients on peritoneal dialysis, and 54 patients with stages 3-5 chronic kidney disease) were studied. Clinical characteristics, markers of mineral metabolism (including fibroblast growth factor-23 [FGF-23]) and inflammation (high-sensitivity C-reactive protein [hsCRP] and interleukin-6 [IL-6]), and the intima-media thickness (IMT) in the common carotid arteries were measured at baseline. Cardiac function was assessed by color tissue Doppler echocardiography. After 36 months follow-up, the survival rate by Kaplan-Meier analysis was significantly different according to OPG levels (χ2=14.33; P=0.002). Increased OPG levels were positively associated with IL-6 (r=0.38, P<0.001), FGF-23 (r=0.26, P<0.001) and hsCRP (r=0.0.24, P=0.003). In addition, OPG was positively associated with troponin I (r=0.54, P<0.001) and IMT (r=0.39, P<0.0001). Finally, in Cox analysis, only OPG (HR=1.07, 95%CI=1.02-1.13) and hsCRP (HR=1.02, 95%CI=1.01-1.04) were independently associated with increased risk of death. These results suggested that elevated levels of serum OPG might be associated with atherosclerosis and all-cause mortality in patients with chronic kidney disease.