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    Optical polarization study in the open cluster NGC 6250

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    We present (UBVRI) multicolour linear polarimetric data for 32 of the brightest stars in the area of the open cluster NGC 6250, with the aim of studying the properties of the interstellar medium (ISM) towards the cluster. Our data yield a mean polarization P¯V = 1.83 per cent, close to the polarization value produced by the ISM with normal efficiency for a mean colour excess of EB−V = 0.37. Our analysis indicates that the observed visual absorption in NGC 6250 is caused by a nearby dust layer (within 300 pc) producing a polarization with an angle close to the Galactic plane (θGP ∼ 38◦). In addition, there are at least two more dust layers along the line of sight between the Sun and the cluster producing a change in the observed polarization, making our results compatible with Neckel and Klare’s results. The observations show differences between the orientation of the local magnetic field of the nearby dust layer and the one that is polarizing along the way to the cluster (θ v = 20◦). The internal dispersion of the polarization values for the members of NGC 6250 seems to be compatible with the presence of intracluster dust. The majority of observed stars do not present evidence of intrinsic polarization in their light. In this work, we also show (as in several previous papers) how polarimetry is an excellent technique for identifying non-member stars.Fil: Feinstein Baigorri, Carlos. 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: Vergne, Maria Marcela. 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: Martinez, Ruben Enrique. 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: 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: Vergne, Maria Marcela. 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

    Essays on Violence-Driven Migration and its Impact on Immigrants’ Origin Countries

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    Rampant gang-related violence in the Northern Triangle of Central America is increasingly pushing both children and adults to make the risky migration journey to the north. Simultaneously, as a result of the strengthening of U.S. immigration enforcement policies, an increasing number of Central Americans are being repatriated to their countries of origin. This dissertation presents a collection of essays that evaluate the consequences of these migration flows in the country of origin of immigrants providing evidence from El Salvador, a country with nearly one quarter of its population residing abroad and exhibiting one of the highest homicide rates in the world. Chapter 2 advances understanding on the formation, development and consequences of gangs in Central America by bringing together multi-disciplinary evidence. These studies show that gangs are the result of internal conflicts and violence, marginalization, migration, social exclusion, rapid urbanization and lack of economic opportunities for youths, which have existed in these countries for decades. Central American gangs, whose origin can be traced to the U.S. deportation of Salvadorans with a criminal background, grew in power and organization through the implementation of tough-on-crime or \textit{Mano Dura} policies. Gangs are now evidenced to adversely impact the communities they govern by hindering economic and human capital development. Chapter 3 empirically examines how recent deportations of Salvadorans with and without a criminal background impact local gangs and violent crime. This study finds that in municipalities dominated by gangs, the repatriation of Salvadorans without a criminal background leads to an increase in homicides, whereas criminal deportations lead to a reduction in violent crime. These contrasting effects are explained by three main mechanisms: most-serious criminal deportees continue contributing to gang membership and gang-related violence; less-serious criminal deportees have a positive contribution to the local labor market, which decreases their likelihood of re-offending and in turn reduces violent crime; young male non-criminal deportees are becoming the victims of violent crime as they represent the perfect target for gang recruitment. Lastly, Chapter 4 evaluates the impact of parent international migration on educational outcomes of children left behind in El Salvador. This study evidences that children with migrant parents exhibit a lower probability of attending school, where the effect is driven by older boys and girls, ages 13 to 17. Although remittances play an important role in decreasing financial constraints in Salvadoran households, they do not fully compensate for the adverse consequences of parental absence due to migration. As a result, there are labor readjustments within the household where boys are replacing school for work and girls are more prone to be inactive, likely carrying out more housework

    Radiocarbon reservoir ages and hardwater effect for the northeastern coastal waters of Argentina.

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    Accelerator mass spectrometry (AMS) radiocarbon dates were obtained for 18 mollusk shells collected alive along the Buenos Aires province coast, Argentina, over the period AD 1914–1935. Reservoir ages were estimated for all samples on the basis of the tree-ring calibration curve for the Southern Hemisphere (SHCal04, McCormac et al. 2004) and the marine ΔR values calculated as the difference between the conventional 14C age and the age deduced from the marine, mixedlayer model calculation (Marine04, Hughen et al. 2004). For most coastal locations, a great ΔR scatter was observed, ranging from 191 to 2482 yr, which is explained by the input of varying content of dissolved carbonate by rivers and groundwater (“hardwater effect”) and indicates a serious limitation for shell-based 14C chronologies. Within the interior of Bahía Blanca estuary, ΔR values ranged from –40 to 50 ± 46 as a consequence of the local geological particularities of the environment. This suggests that, with some restrictions, the marine calibration curve with standard parameters (ΔR = 0) could be used at this location.Fil: Gomez, Eduardo Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Borel, Claudia Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Aguirre, Marina Laura. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Martinez, Daniel Emilio. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Geología de Costas y del Cuaternario. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto de Geología de Costas y del Cuaternario; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Chia (Salvia hispanica L.) oil stability: Study of the effect of natural antioxidants

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    The chia seed (Salvia hispanica L.) is globally popular and valued for its nutritional and health attributes. Chia oil is mainly composed of triglycerides, in which polyunsaturated fatty acids (PUFAs, linoleic and α-linolenic acids) are found in high amounts. Although it seems evident that such fatty acid composition is favorable from a nutritional point of view, a higher content of linoleic and linolenic acids results in poorer oxidative stability and shorter shelf life of the oil. The aim of this study was to evaluate the combined effects of the storage condition (300 days under fluorescent light - 800 Lux - or in the dark, both at room temperature) with the addition of natural antioxidants (rosemary extract, RE; tocopherol, TOC; ascorbyl palmitate, AP). In the dark, the combined addition of AP and TOC significantly reduced lipid oxidation and improved oil shelf life. Moreover, this combination maintained an acceptable quality of at least up to 300 storage days. Results from this work highlight the influence of illumination condition on chia oil oxidative stability, suggesting that this oil should be stored in containers with light-barrier properties, and probably added to the antioxidants examined in the current study.Fil: Bodoira, Romina Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Penci, Maria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Ribotta, Pablo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Martinez, Marcela Lilian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentin

    Study of the preparation process and variation of wall components in chia (Salvia hispanica L.) oil microencapsulation

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    A study of the microencapsulation process of omega-3 rich oil extracted from chia (Salvia hispanica L.) seeds was carried out, which included a comparative analysis of the microcapsules obtained by the spray- and freeze-drying methods using isolated soy proteins and maltodextrin as wall materials at different proportions. Color characterization of the obtained powders was performed and revealed a darker and yellower appearance of the freeze-dried samples compared with the spray-dried ones. Moisture content was measured for each sample and all presented values around 3.5%. The SEM micrographs revealed that spray-dried microcapsules can occur individually or may form clusters or aggregates, with the particles exhibiting a size range varying from 4 to 10 µm. Encapsulation efficiency was measured, with no significant differences found between drying methods or on varying the proportion of wall components (all samples presented values of aproximately 60%). The oxidative stability of microencapsulated oils under accelerated oxidative conditions revealed protection factors 2-fold higher for all samples. In addition, microencapsulated oil stored under 25 ºC revealed lower hydroperoxide values than those of unencapsulated oil throughout the whole storage test. Finally, oil encapsulated in SPI microcapsules also showed lower HPV values than that of the acceptable limit for virgin and cold-pressed vegetable oils (15 meq. O2/kg oil) during the storage test, while unencapsulated oil attained the acceptable limit in 62 days. This result represents an increase in the time of the oil shelf life of between 30 and 48%.Fil: González, Agustín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Martinez, Marcela Lilian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Paredes, Alejandro Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; ArgentinaFil: Leon, Alberto Edel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Ribotta, Pablo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; Argentin

    Perception of neighborhood crime and drugs Increases cardiometabolic risk in Chilean adolescents

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    PURPOSE: Studies report an association between neighborhood risk and both obesity and cardiometabolic risk factors (CMR) among adolescents. Here we describe the effect of perceived neighborhood risk on adiposity and CMR among Chilean adolescents. METHODS: Participants were 523 low- to middle-income Chilean adolescents. We assessed neighborhood risk in early adolescence, adiposity in childhood and in early and later adolescence, and blood pressure and fasting glucose in later adolescence. Neighborhood risk profiles were estimated using latent profile analysis (LPA) and based on reported perceptions of crime and drug sales/use. Using linear and logistic regression, we examined the effect of neighborhood risk on adiposity and CMR. RESULTS: Mean age in early and later adolescence was 14 and 17 years, respectively. Participants were 52% male, with a mean BMI z-score of .67, and 8% met criteria for metabolic syndrome. LPA identified two neighborhood profiles: 61% low risk and 39% high risk. In later adolescence, being in the high risk profile predicted a higher BMI z-score, waist-to-height ratio, and fat mass index (p < .05). Adolescents in the high risk profile had three times greater odds of meeting criteria for metabolic syndrome (OR = 3.1, 95% CI: 1.5, 5.8) compared with those in the low risk profile. CONCLUSIONS: Our findings suggest that there are physiological responses to living in a neighborhood perceived as "risky," which may contribute to obesity and CMR even in adolescence. For Chilean neighborhoods with high crime and drugs, targeted public health interventions and policies for youth could be beneficial.This research was funded by R01HL088530 (NIH-NHLBI, PI: Gahagan); R01HD33487 (NIH-NICHD, PIs: Lozoff and Gahagan); R01DA021181 (NIH-NIDA, PI: Delva). The first author acknowledges D. Eastern Kang Sim for his support. All authors would like to thank the study participants for their on-going commitment to the project. (R01HL088530 - NIH-NHLBI; R01HD33487 - NIH-NICHD; R01DA021181 - NIH-NIDA

    The history and evolution of the residential mortgage market in Mexico : a look at its future

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    Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture; and, Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 1998.Includes bibliographical references (leaves 95-98).Research was conducted in Mexico in order to determine the size, future growth and current status of the Mexican residential mortgage market, and to assess the potential for securitization. Securitization offers good prospects of liquifying the mortgage loans enabling these funds to be reinvested into the housing market. In the long run, securitization can also attract other sources of capital, both foreign and domestic, to the housing market. The key elements of structuring these securities lie in the underwriting standards and loan origination systems that are effectuated. Poor origination and collecting practices will hinder the success of securitization. The development of an efficient primary market would facilitate the sale of loans in the secondary market, increasing capital flow efficiencies. Interviews with private and Federal authorities confirmed that securitization is being actively pursued and encouraged by the Mexican government. Some of the important questions to be answered are; how quickly can the primary market be developed, what impact will the new foreclosure laws have on recovery rates, what demand will the domestic markets have for these securities, and how quickly can foreign investment be attracted. But at this moment, the most important question to be answered is to what degree the government should be involved in developing the secondary market. It was found that FOVI will be further developed to act as an originating agency since it is currently one of the only sources of funding for residential mortgages in Mexico. The immediate future for securitizing mortgages rests on the precedent set by these new FOVI loans.by Marcela Fernandez Martinez and Anthony James Simboli.S.M

    Circadian rhythms of proliferation events in two mouse carcinomas

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    We studied the index of DNA synthesis (DNAs) of two cellular carcinomas: the hepatocellular ES12a and the mammary TN60 of mice, throughout one circadian cycle. In the results, we observed that both tumors have circadian rhythms (CRs), but the peaks of DNAs vary. Besides, the mean of DNAs along 24 h shows significative differences, the TN60 has higher values than the ES12a. These observed CR in the DNAs index in both carcinomas mean that, at least in partly, the proliferation of cancer cells can be regulated by endocrine factor as it normally occurs in ordinary cells. The big problem we can find for the chronopharmacology is that it is impossible to know in advance the rate of proliferation of each tumor.Fil: Garcia, Marcela. Universidad Nacional de la Plata. Facultad de Ciencias Médicas; ArgentinaFil: Andrini, Laura Beatríz. Universidad Nacional de la Plata. Facultad de Ciencias Médicas; ArgentinaFil: Martinez, Marina. Universidad Nacional de la Plata. Facultad de Ciencias Médicas; ArgentinaFil: Inda, Ana. Universidad Nacional de la Plata. Facultad de Ciencias Médicas; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; ArgentinaFil: Palma, Maria Belen. Universidad Nacional de la Plata. Facultad de Ciencias Médicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Miriuka, Santiago Gabriel. Universidad Nacional de la Plata. Facultad de Ciencias Médicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Errecalde, Ana Lia. Universidad Nacional de la Plata. Facultad de Ciencias Médicas; Argentin
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