Experimental Investigation of the Distribution of Shock Effects in Regolith Impact Ejecta Using an Ejecta Recovery Chamber

Because the mass-flux of solar system meteoroids is concentrated in the approx. 200 microns size range, small-scale impacts play a key role in driving the space weathering of regoliths on airless bodies. Quantifying this role requires improved data linking the mass, density and velocity of the incoming impactors to the nature of the shock effects produced, with particular emphasis on effects, such as production of impact melt and vapor, that drive the optical changes seen in space weathered regoliths. Of particular importance with regard to space weathering is understanding not only the composition of the shock melt created in small-scale impacts, but also how it is partitioned volumetrically between the local impact site and more widely distributed ejecta. To improve the ability of hypervelocity impact experiments to obtain this type of information, we have developed an enclosed sample target chamber with multiple-geometry interior capture cells for in-situ retention of ejecta from granular targets. A key design objective was to select and test capture cell materials that could meet three requirements: 1) Capture ejecta fragments traveling at various trajectories and velocities away from the impact point, while inducing minimal additional damage relative to the primary shock effects; 2) facilitate follow-up characterization of the ejecta either on or in the cell material by analytical SEM, or ex-situ by microprobe, TEM and other methods; and 3) enable the trajectories of the captured and characterized ejecta to be reconstructed relative to the target

FTIR Analysis of Water in Pyroxene and Plagioclase in ALH 84001 and Nakhlites

Determining the volatile budget of the interior of Mars is crucial for our understanding of that planet's formation, geodynamics, cooling history and the origin of its volcanism and atmosphere as well as its potential for life. Surficial water is evident from spacecraft and rover data in polar caps and the atmosphere, in the presence of river channels, and in the detection of water-bearing minerals. Meteorites, however, are our best candidates for estimating the amount of water present at depth, even if all are crustal samples. The last 10 years have seen a blooming of studies measuring water and halogens in Martian meteorites. The bulk of these studies target phosphate, a typically late-stage phase in the igneous Martian meteorites that potentially would concentrate incompatible element hydrogen (H quantified traditionally as "water", i.e., H2O concentrations in weight) near the end of the crystallization sequence. However, determining the amount of water, F, and Cl in the magma from which a phosphate crystallized from is not straightforward and in most instances not possible. On the other hand, phosphates have turned out to be very useful in identifying hydrothermal processes that could have added water while or after the magma flowed and crystallized. Another caveat of analyzing Martian meteorite phases for water is that shocked phases such as maskelynite and impact melts appear to have incorporated water from the Martian atmosphere, as evidenced by high H isotope ((delta)D) signatures, and therefore their water concentrations cannot be interpreted in terms of deep planetary processes. The best candidates for estimating the water content of the Martian interior have been melt inclusions (glass or amphibole-bearing) which the enclosing mineral (usually olivine) would have prevented from exchanging volatiles with the surroundings after crystallization. Even some of these, however, have high (delta)D, meaning they were affected by H exchange via impact events or with crustal reservoirs or hydrothermal fluids. Here, nominally anhydrous minerals (pyroxene, olivine, plagioclase, or maskelynite) in orthopyroxenite ALH 84001 and selected nakhlites are analyzed for water and major elements, in order to determine 1) whether they contain any water; 2) if they do, what controls its distribution (crystallization, degassing, hydrothermal or impact processes); and 3) if any of these measurements can be used to infer the water contents of the parent magma and their mantle sources. A shock-reverberation experiment was also performed on terrestrial orthopyroxenes (opx) to simulate the heavily shocked conditions of ALH 84001 (> 31 GPa [17])

Breastfeeding and Related Factors in Afrodescendant Women From Cartagena, Colombia

Objective: To describe practices and related factors to breastfeeding in afrodescendant women from Cartagena de Indias city, Colombia. Material and Methods: Cross-sectional study conducted between 2016 and 2017 in 548 mothers who had under 5 years children from afrodescendant communities. A self-reported questionnaire was applied, asking for sociodemographic variables, breastfeeding time and exclusive breastfeeding, family support and factors related to this practice. Data were analyzed  by descriptive statistics and risk estimation by Odds Ratio (OR). Results: Most mothers were young adults (89.8%), having high scholar level (55.2%), family support and they were associated to the public health system. The prevalence of breastfeeding and exclusive breastfeeding during the first 6 months was 91.6% and 80.4%, respectively. Breastfeeding and exclusive breastfeeding practice were associated with mother's age (OR = 3.24, 95% CI= 1.80-5.8) and low mother's educational level (OR = 3.24, 95% CI= 1.8-5.8). Finally, no breastfeeding and the fact of not being performed exclusively was associated with no mother nipples examination, and not or insufficient information supplied about this issue. Conclusion: Breastfeeding practice was associated with mother's age and her educational level as well as with poor preparation to start this practice. Although its prevalence was high, it is necessary to implement policies within health system to encourage its practice and provide measures to solve problems during their development in mothers from vulnerable communities

Improved Measurement of Ejection Velocities From Craters Formed in Sand

A typical impact crater is formed by two major processes: compression of the target (essentially equivalent to a footprint in soil) and ejection of material. The Ejection-Velocity Measurement System (EVMS) in the Experimental Impact Laboratory has been used to study ejection velocities from impact craters formed in sand since the late 1990s. The original system used an early-generation Charge-Coupled Device (CCD) camera; custom-written software; and a complex, multicomponent optical system to direct laser light for illumination. Unfortunately, the electronic equipment was overtaken by age, and the software became obsolete in light of improved computer hardware

Experimental Impact Laboratory

No abstract availabl

Adicción a redes sociales y habilidades sociales en escolares de nivel secundaria del departamento de Puno en época de Covid 19

La presente investigación busca describir la relación entre la adicción a las redes sociales y las habilidades sociales en adolescentes en etapa escolar en el departamento de Puno ante la coyuntura del COVID 19. Esta investigación nació a partir del cuestionamiento e interés por conocer a profundidad sobre un tema tan trascendental en la historia de la humanidad como es el uso de las redes sociales y la tecnología. Si bien existen investigaciones respecto a este tema, muy pocas se habrían efectuado durante la coyuntura de COVID-19. Por otra parte, se quiso establecer la relación entre dos variables y si realmente alguna generaba algún tipo de modificación o alteración en la conducta. En el ámbito profesional, como psicólogas, el interés versó en conocer el contexto conductual del adolescente ante el uso de esta herramienta. Dentro del capítulo primero se presenta, el estudio y su planteamiento, el cual evidencia la formulación del problema y su pregunta de investigación, así mismo, explica el objetivo general, los objetivos específicos, por último, exhibe la importancia y justificación del estudio, así como sus limitaciones. En el segundo capítulo, presenta el marco teórico, se indican las investigaciones nacionales e internacionales, las bases teórico-científicos y se definen los términos básicos de investigación. Dentro del tercer capítulo, se ven demostradas las hipótesis y sus variables junto a sus supuestos científicos, se detalla la formulación de la hipótesis general y las específicas, también, se describen las variables y sus áreas de análisis. El capítulo cuatro, contiene el método de investigación, delineando las características de la población, la muestra y los participantes; explica el tipo y diseño de investigación, manifestando las técnicas e instrumentos de recolección de datos; finalmente, detalla los procedimientos y técnicas de procesamiento de datos. En el quinto capítulo, se manifiestan de manera precisa los resultados obtenidos, se detalla el análisis realizado y su discusión. Finalmente, el sexto capítulo, ciñe las conclusiones y recomendaciones finales, es decir, las conclusiones generales y específicas, las mismas que se originan naturalmente luego de analizar los resultados obtenidos. Se detallan las recomendaciones, las mismas que dan pie a futuras investigaciones similares; se presenta el resumen y por último, se expresan las referencias bibliográficas y los anexo

PERFIL BIOPSICOSOCIAL DE LA MADRE Y SU RELACIÓN CON EL ABANDONO DE LACTANCIA MATERNA EXCLUSIVA

Exclusive maternal lactation is a form of infant nutrition without equal. Nevertheless, in spite of the importance of exclusive maternal lactation; at the present time a problem of its early abandonment exists due to the lack of effective policies for its promotion. The objective of this investigation was to establish if a relation between the bio-psychosocial profile of the mother and the abandonment of exclusive maternal lactation exists. The methodology was framed within the quantitative design, of cross section correlation type. The population was 106 mothers of children under the age of six months that visited the pediatrics department of the health unit Dr. Diaz Carballo and the Medical Group Miranda, the sample was representative of the whole conformed by 60 mothers, distributed in two groups: 30 mothers who gave exclusive maternal lactation and 30 that had stopped. Data appear in graphs of percentages using statistics of the square of chi with correction of Yates. Results: the age, the psychological aspect, the habits of the mother maintain a statistically significant relation with the abandonment of exclusive maternal lactation. One concludes that the bio-psychosocial factors (age, parity, psychological aspect, and culture) can become obstacles to the mother practicing exclusive a maternal lactation. The social aspect (social status) does not have relevance to the abandonment of exclusive maternal lactation, similarly to the origin of the mother.La lactancia materna exclusiva es una forma inigualable de nutrición infantil. Sin embargo, a pesar de la importancia que tiene la lactancia materna exclusiva, en la actualidad existe un problema de abandono precoz de la misma debido a la falta de políticas efectivas en pro de su promoción. El objetivo de esta investigación fue establecer si existe relación entre el perfil biopsicosocial de la made y el abandono de la lactancia materna exclusiva. La metodología fue enmarcada dentro del diseño cuantitativo, de tipo correlacional de corte transversal. La población fue de 106 madres de niños menores de seis meses que asistían a las consultas de niños sanos de la unidad sanitaria Dr. Cándido Díaz Carballo y el Grupo Médico Miranda, la muestra fue representativa del Universo conformada por 60 madres, distribuida en dos grupos: 30 madres que daban lactancia materna exclusiva y 30 que habían abandonado la misma. Los datos se presentan en cuadros de distribución de porcentajes utilizando el estadístico de chi cuadrado con corrección de Yates. Resultados: la edad, el aspecto psicológico, las costumbres de la madre guardan relación estadísticamente significativa con el abandono de la lactancia materna exclusiva. Se concluye que los factores biopsicosociales como son la edad, la paridad, el aspecto psicológico, la cultura se puede convertir en obstáculo para que la madre practique una lactancia materna exclusiva y el aspecto social como es el status social no tiene relevancia para el abandono de lactancia materna exclusiva al igual que la procedencia de la madr

Impact Shocking of a Zircon-Sanidine Mixture and Investigations of Pb Mobility

The purpose of this project is to explore the mobility, mixing, and possible clumping of Pb isotopes during laboratory impact shock experiments. Impact events are a common planetary occurrence and their effect on istotope systematics and subsequent geochronology is not fully understood. By artificially shocking mixtures of zircon and sanidine and investigating the sample products, it may be possible to understand if and how Pb is mobilized during impact shock. Isotopes of Pb are the final daughter products of the decay chains of 238U, 235U and 232Th and therefore understanding how mobile the daughter product is during impact events could have consequences for dating impact events. These investigations will also reveal if Pb isotopes can be mixed between minerals

Impact Shocking of a Zircon-Sanidine Mixture and Investigations of Pb Mobility

The purpose of this project is to explore the mobility, mixing, and possible clumping of Pb isotopes during laboratory impact shock experiments. Impact events are a common planetary occurrence and their effect on istotope systematics and subsequent geochronology is not fully understood. By artificially shocking mixtures of zircon and sanidine and investigating the sample products, it may be possible to understand if and how Pb is mobilized during impact shock. Isotopes of Pb are the final daughter products of the decay chains of 238U, 235U and 232Th and therefore understanding how mobile the daughter product is during impact events could have consequences for dating impact events. These investigations will also reveal if Pb isotopes can be mixed between mineral