1,140 research outputs found

    Dust properties in NGC 6611

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    An investigation on dust properties in the NW portion of NGC 6611 has been conducted polarimetrically to test the existence of abnormal extinction in that section of the open cluster in an independent way. As previously suggested for the η Carinae nebula by Tapia et al. (1988b) and subsequently confirmed by Marraco et al. (1993), the canonical relation between EV −K/EB−V and λmax (the wavelength of maximun interstellar polarization) is not valid for stars belonging to dusty H ii regions, as is the case for the observed portion of M 16. This may arise mainly from the presence of silicate grains of a slightly larger size than the standard ISM and also from a considerable increase in mean graphite grain size, according to previous results from Chini & Wargau (1990). About 50% of the observed stars in NGC 6611 present indications of intrinsic polarization in their measurements; a similar percentage was found in IC 2944 (Vega et al. 1994), another young open cluster in close relation with an H ii region.Fil: Orsatti, Ana Maria. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; ArgentinaFil: Vega, Ema Irene. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Marraco, Hugo Gustavo. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentin

    Pismis 20: one or two clusters?

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    We present UBVRI polarimetric observations of stars in the direction of the open cluster Pismis 20 and WR 67. It is found that the observed members segregate polarimetrically into two groups, with different associated mean Pmax (4.31 and 6.08% respectively). Although in the literature these stars are considered as members of the same cluster, the polarized light from these groups clearly differs. There are two possible explanations: very efficient polarizing dust particles exists between certain members of the cluster; or else Pismis 20 is composed of different groupings superimposed along the line of sight. WR 67 belongs to the group more affected by the dust.Fil: Orsatti, Ana Maria. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica la Plata; ArgentinaFil: Vega, Ema Irene. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Marraco, Hugo Gustavo. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica la Plata; Argentin

    Open Clusters in Carina: NGC 3603, Westerlund 2 and Sher 1

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    Se presentan observaciones polarimétricas en las bandas U BV RI de estrellas situadas en la dirección de los cúmulos NGC 3603, Westerlund 2 y Sher 1, con el propósito de estudiar las características del polvo entre el Sol y los cúmulos, evidencias polarimétricas de la existencia (o no) de enrojecimiento anómalo en NGC 3603 y en Westerlund 2, y la identificación de estrellas con indicios de polarización intrínseca. 40% de las estrellas observadas en Westerlund 2 presentan indicios de polarización intrínseca, porcentaje similar al encontrado en NGC 6611 y en IC 2944; en cambio, en NGC 3603 es mucho menor. Las eficiencias polarimétricas medias son bajas por la presencia de varias nubes de polvo interestelar entre los objetos y el Sol. Se apoya la existencia de enrojecimiento anómalo en NGC 3603, mientras que en Westerlund 2 existen leves indicios de ello.We present polarimetric observations in the UBV RI bands of stars located in the directions of NGC 3603, Westerlund 2 and Sher 1. Our main objectives are to study the characteristics of the dust lying between the Sun and the clusters, to analyze polarimetric evidence on the existence (or not) of abnormal reddening in NGC 3603 and Westerlund 2; and to identify stars with signatures of intrinsic polarization. 40% of the stars observed in Westerlund 2 display indications of intrinsic polarization, a percentage similar to those found in the open clusters NGC 6611 and IC 2944: but in NGC 3603 it is very small. Mean polarization efficiencies are low, due to the presence of several dust clouds located in the way to the clusters. We are in favor of the existence of abnormal reddening in NGC 3603, while in Westerlund 2 there are only indications.Fil: Orsatti, Ana Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Astrofísica La Plata; Argentina; Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina;Fil: Vega, Ema Irene. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina;Fil: Martinez, Ruben Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Astrofísica La Plata; Argentina; Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina

    Methodology of image analysis for study of the vertisols moisture content

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    The main problem to study vertical drainage from the moisture distribution, on a vertisol profile, is searching for suitable methods using these procedures. Our aim was to design a digital image processing methodology and its analysis to characterize the moisture content distribution of a vertisol profile. In this research, twelve soil pits were excavated on a ba re Mazic Pellic Vertisols ix of them in May 13/2011 and the rest in May 19 /2011 after a moderate rainfall event. Digital RGB images were taken from each vertisol pit using a Kodak? camera selecting a size of 1600x945 pixels. Each soil image was processed to homogenized brightness and then a spatial filter with several window sizes was applied to select the optimum one. The RGB image obtained were divided in each matrix color selecting the best thresholds for each one, maximum and minimum, to be applied and get a digital binary pattern. This one was analyzed by estimating two fractal scaling exponents box counting dimension D BC) and interface fractal dimension (D) In addition, three pre-fractal scaling coefficients were determinate at maximum resolution: total number of boxes intercepting the foreground pattern (A), fractal lacunarity (?1) and Shannon entropy S1). For all the images processed the spatial filter 9x9 was the optimum based on entropy, cluster and histogram criteria. Thresholds for each color were selected based on bimodal histograms

    Nuestro Campus También es Patrimonio Cultural I

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    Proyecto de innovación docente vinculado a materias relacionadas con la gestión del Patrimonio Cultural. Este proyecto se desarrolla sobre un escenario práctico donde aprender los temas objeto de estudio: la Ciudad Universitaria de Madrid. Persigue establecer nuevos lazos de sociabilidad entre la comunidad universitaria y los bienes culturales. Está basado en metodologías de investigación acción participativa. Así mismo persigue dar a conocer el campus y plantear nuevas actuaciones que mejoren dicho espacio público

    Sleep and diet quality in adolescents

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    Background: Inability to sleep increases the vulnerability of overeating in particular high calorie density foods considering the current obesogenic environment. In addition, scientific research has shown that a healthy and balanced diet positively influences sleep quality. Objectives: This study aimed to evaluate the quality of sleep of adolescents in the county of Bragança and its association with diet quality. Methods: It was carry out the study in a population of 345 high school students. The data was collected in May 2017 through a questionnaire that included the Pittsburgh Sleep Quality Index (PSQI), by Ramalho (2008). Results: Throughout the study and following PSQI analysis, it was concluded that 39.71% (n=137) of participants showed poor quality of sleep (PSQI >5 points). The correlation between sleep quality and diet quality was assessed and a statistically significant association was found between the quality of sleep and the intake of snacks (X2=17.144; p≤0.001), sugary products (X2=18.603; p=0.000), fast-food (X2=12.353; p=0.002) and ready meals (X2=14.852; p≤0.001). The risk of suffering from poor sleep quality is higher in young populations who frequently eat snacks ([OR]: 2.811; 99%), sugary products ([OR]: 1.901; 95%), fast-food ([OR]: 4.000; 99%) and ready meals ([OR]: 5.621; 95%) in comparison with young populations who rarely eat this sort of food. The sleep quality is also significantly related to the number of correct eating habits (test t = 4.857, p≤0.001). Adolescents with good sleep quality presented a greater number of correct eating habits (mean: 7.85) compared to students with poor sleep quality (mean: 6.55). Conclusions: Through the analysis of the results, the correlation between sleep quality and dietary quality is evident. The risk of having poor quality of sleep is higher in students who frequently eat a high calorie diet and also in students who have fewer healthy eating habits.info:eu-repo/semantics/publishedVersio

    Grado de endeudamiento y su relación con la rentabilidad en las empresas del sector industrial. Perú, 2019

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    La presente investigación se desarrolló con el fin de determinar en qué medida se relacionan el endeudamiento y la rentabilidad en las empresas del sector industrial que cotizan en la Bolsa de Valores de Lima en el año 2019. El tipo de investigación fue cuantitativa, aplicada, no experimental y transversal; se tomó una muestra de 26 empresas industriales, de las cuales se recolectó el estado de resultados y el balance general pertenecientes al año 2019 de la página web de la BVL, a los datos obtenidos se aplicaron ratios financieros, los cuales fueron grado de endeudamiento, ROE y ROA, ello sirvió para analizar el grado de endeudamiento y la rentabilidad de las empresas industriales. Finalmente, se aplicó el coeficiente de correlación de Pearson mediante el software estadístico SPSS, del cual se obtuvo una relación positiva y muy fuerte tanto para el grado de endeudamiento y ROE de 88.2% y para grado de endeudamiento y ROA con un resultado de 94.6%. Además, ambos presentaron un resultado altamente significativo debido a que el valor de ambas relaciones (Grado de endeudamiento- ROE y Grado de endeudamiento-ROA) es incluso menor al 1% (0.000)

    Strontium ranelate effect on bone mineral density is modified by previous bisphosphonate treatment

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    The aim of this study was to evaluate the effect of strontium ranelate (SrR) on bone mineral density (BMD) and boneturnover markers after 1 year of treatment. Additionally, theeffect of SrR in bisphosphonate-naïve patients (BP-naïve)compared to patients previously treated with bisphosphonates (BP-prior) was analyzed. This retrospective study included482 postmenopausal women treated with SrR (2 g/day) for 1year in ten Argentine centers; 41 patients were excludeddue to insufficient data, while 441 were included. Participants were divided according to previous bisphosphonatetreatment in two groups: BP-naïve (n = 87) and BP-prior (n = 350). Data are expressed as mean ± SEM. After 1 year oftreatment with SrR the bone formation markers total alkaline phosphatase and osteocalcin were increased (p < 0.0001),while the bone resorption marker s-CTX was decreased (p =0.0579). Also increases in BMD at the lumbar spine (LS,3.73%), femoral neck (FN, 2.00%) and total hip (TH, 1.54%) [p < 0.0001] were observed. These increments were significant(p < 0.0001) both among BP-naïve and BP-prior patients. Interestingly, the change in BMD after 1 year of SrR treatmentwas higher in BP-naïve patients: LS: BP-naïve = 4.58 ± 0.62%; BP-prior = 3.45 ± 0.28% (p = 0.078). FN: BP-naïve = 2.79 ±0.56%; BP-prior = 2.13 ± 0.29% (p = 0.161). TH: BP-naïve = 3.01± 0.55%; BP-prior = 1.22 ± 0.27% (p = 0.0006). SrR treatmentincreased BMD and bone formation markers and decreaseda bone resorption marker in the whole group, with betterresponse in BP-naïve patients.Fil: Brun, Lucas Ricardo Martín. Universidad Nacional de Rosario. Facultad de Ciencias Médicas. Laboratorio de Biología Ósea; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Galich, Ana M.. Hospital Italiano; ArgentinaFil: Vega, Eduardo. Instituto de la Mujer. Buenos Aires; ArgentinaFil: Salerni, Helena. Consultorios de Investigación Clínica Endocrinológica y del Metabolismo Óseo ; ArgentinaFil: Maffei, Laura. Consultorios Asociados de Endocrinología Dra. Laura Maffei; ArgentinaFil: Premrou, Valeria. Consultorios Asociados de Endocrinología Dra. Laura Maffei; ArgentinaFil: Costanzo, Paulo R. Consultorios de Investigación Clínica Endocrinológica y del Metabolismo Óseo ; ArgentinaFil: Sarli, Marcelo A. Instituto de Investigaciones Metabólicas Dr. Zanchetta; ArgentinaFil: Rey, Paula. Instituto de Investigaciones Metabólicas Dr. Zanchetta; ArgentinaFil: Larroudé, Maria S.. Hospital César Milstein; ArgentinaFil: Moggia, Maria S.. Centro Tiempo; ArgentinaFil: Brance, María Lorena. Universidad Nacional de Rosario. Facultad de Ciencias Médicas. Laboratorio de Biología Ósea; ArgentinaFil: Sánchez, Ariel. Centro de Endocrinología; ArgentinaFil: Grupo Argentino de Estudio del Ranelato de Estroncio. No especifica

    The tyrosine kinase FER is responsible for the capacitation-associated increase in tyrosine phosphorylation in murine sperm

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    Sperm capacitation is required for fertilization. At the molecular level, this process is associated with fast activation of protein kinase A. Downstream of this event, capacitating conditions lead to an increase in tyrosine phosphorylation. The identity of the tyrosine kinase(s) mediating this process has not been conclusively demonstrated. Recent experiments using stallion and human sperm have suggested a role for PYK2 based on the use of small molecule inhibitors directed against this kinase. However, crucially, loss-of-function experiments have not been reported. Here, we used both pharmacological inhibitors and genetically modified mice models to investigate the identity of the tyrosine kinase(s) mediating the increase in tyrosine phosphorylation in mouse sperm. Similar to stallion and human, PF431396 blocks the capacitation-associated increase in tyrosine phosphorylation. Yet, sperm from Pyk2(-/-) mice displayed a normal increase in tyrosine phosphorylation, implying that PYK2 is not responsible for this phosphorylation process. Here, we show that PF431396 can also inhibit FER, a tyrosine kinase known to be present in sperm. Sperm from mice targeted with a kinase-inactivating mutation in Fer failed to undergo capacitation-associated increases in tyrosine phosphorylation. Although these mice are fertile, their sperm displayed a reduced ability to fertilize metaphase II-arrested eggs in vitro.Fil: Alvau, Antonio. University of Massachussets; Estados UnidosFil: Battistone, Maria Agustina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Gervasi, Maria Gracia. University of Massachussets; Estados UnidosFil: Navarrete, Felipe A.. University of Massachussets; Estados UnidosFil: Xu, Xinran. State University of Colorado - Fort Collins; Estados UnidosFil: Sánchez Cárdenas, Claudia. Universidad Nacional Autónoma de México. Instituto de Biotecnología; MéxicoFil: De la Vega Beltran, José Luis. Universidad Nacional Autónoma de México. Instituto de Biotecnología; MéxicoFil: Da Ros, Vanina Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Greer, Peter. Queens University; CanadáFil: Darszon, Alberto. Universidad Nacional Autónoma de México. Instituto de Biotecnología; MéxicoFil: Krapf, Diego. State University of Colorado - Fort Collins; Estados UnidosFil: Salicioni, Ana María. University of Massachussets; Estados UnidosFil: Cuasnicu, Patricia Sara. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Visconti, Pablo E.. University of Massachussets; Estados Unido
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