Strong Clustering of Lyman Break Galaxies around Luminous Quasars at z~4

In the standard picture of structure formation, the first massive galaxies are expected to form at the highest peaks of the density field, which constitute the cores of massive proto-clusters. Luminous quasars (QSOs) at z~4 are the most strongly clustered population known, and should thus reside in massive dark matter halos surrounded by large overdensities of galaxies, implying a strong QSO-galaxy cross-correlation function. We observed six z~4 QSO fields with VLT/FORS exploiting a novel set of narrow band filters custom designed to select Lyman Break Galaxies (LBGs) in a thin redshift slice of Delta_z~0.3, mitigating the projection effects that have limited the sensitivity of previous searches for galaxies around z>~4 QSOs. We find that LBGs are strongly clustered around QSOs, and present the first measurement of the QSO-LBG cross-correlation function at z~4, on scales of 0.1<~R<~9 Mpc/h (comoving). Assuming a power law form for the cross-correlation function xi=(r/r0_QG)^gamma, we measure r0_QG=8.83^{+1.39}_{-1.51} Mpc/h for a fixed slope of gamma=2.0. This result is in agreement with the expected cross-correlation length deduced from measurements of the QSO and LBG auto-correlation function, and assuming a linear bias model. We also measure a strong auto-correlation of LBGs in our QSO fields finding r0_GG=21.59^{+1.72}_{-1.69} Mpc/h for a fixed slope of gamma=1.5, which is ~4 times larger than the LBG auto-correlation length in random fields, providing further evidence that QSOs reside in overdensities of LBGs. Our results qualitatively support a picture where luminous QSOs inhabit exceptionally massive (M_halo>10^12 M_sun) dark matter halos at z~4.Comment: 25 pages, 22 figures, submitted to the Ap

Clustering of Lyman-alpha Emitters Around Quasars at z∼4z\sim4

The strong observed clustering of $z>3.5$ quasars indicates they are hosted by massive ($M_{\rm{halo}}\gtrsim10^{12}\,h^{-1}\,\rm{M_{\odot}}$) dark matter halos. Assuming quasars and galaxies trace the same large-scale structures, this should also manifest as strong clustering of galaxies around quasars. Previous work on high-redshift quasar environments, mostly focused at $z>5$, have failed to find convincing evidence for these overdensities. Here we conduct a survey for Lyman alpha emitters (LAEs) in the environs of 17 quasars at $z\sim4$ probing scales of $R\lesssim7\,h^{-1}\,{\rm{Mpc}}$. We measure an average LAE overdensity around quasars of 1.4 for our full sample, which we quantify by fitting the quasar-LAE cross-correlation function. We find consistency with a power-law shape with correlation length of $r^{QG}_{0}=2.78^{+1.16}_{-1.05}\,h^{-1}\,{\rm{cMpc}}$ for a fixed slope of $\gamma=1.8$. We also measure the LAE auto-correlation length and find $r^{GG}_{0}=9.12^{+1.32}_{-1.31}\,h^{-1}$\,cMpc ($\gamma=1.8$), which is $3.3$ times higher than the value measured in blank fields. Taken together our results clearly indicate that LAEs are significantly clustered around $z\sim4$ quasars. We compare the observed clustering with the expectation from a deterministic bias model, whereby LAEs and quasars probe the same underlying dark matter overdensities, and find that our measurements fall short of the predicted overdensities by a factor of 2.1. We discuss possible explanations for this discrepancy including large-scale quenching or the presence of excess dust in galaxies near quasars. Finally, the large cosmic variance from field-to-field observed in our sample (10/17 fields are actually underdense) cautions one from over-interpreting studies of $z\sim6$ quasar environments based on a single or handful of quasar fields.Comment: 19 pages, 12 figures, submitted to the Ap

Responsabilidad del control interno frente al fraude

"El objetivo de este documento, es comprobar que a pesar de la existencia del control interno en Colombia, se han presentado diferentes situaciones de fraude en las empresas públicas y privadas, por tanto, es importante profundizar en el tema y determinar la responsabilidad que tiene el control interno frente al fraude, siendo éste un mecanismo de control y herramienta gerencial que permite mitigar este riesgo dentro de las organizaciones, por medio de programas o planes antifraude que ayudan a identificar cuellos de botella y neutralizarlos. Así, se realiza un análisis del tema, por medio de una comprensión conceptual y de contexto del mismo, en un país como Colombia. De tal manera, que a través de los casos de fraude que se han presentado en el país, evidenciamos que el diseño e implementación de un sistema de control interno no garantiza la ocurrencia de irregularidades o de actividades fraudulentas

Efecto de las salidas académicas de recreación en las habilidades sociales y el liderazgo de estudiantes de Ciencias del deporte y la Recreación, 2015

La siguiente investigación fue realizada por la necesidad que surge en el programa Ciencias del Deporte y la Recreación de la Universidad Tecnológica de Pereira de cuantificar estadísticamente el efecto que tienen las salidas académicas del área de Recreación sobre las habilidades sociales y de liderazgo de los estudiantes implícitos en ellas; para así permitir reconocer la importancia y contribución de las mismas sobre los estudiantes de 5to y 6to semestre. Además de reconocer que el desarrollo y afianzamiento de las HHSS y de liderazgo son un cimiento transcendental para el proceso académico del estudiante pues estas permiten que crezca no solo profesionalmente, sino en su entorno familiar, social y personal Por tales razones surge la idea de desarrollar una investigación que tuvo como objetivo general: describir el efecto de las salidas académicas del área de recreación en las habilidades sociales y de liderazgo de los estudiantes de 5° y 6° semestre del programa Ciencias del Deporte y la Recreación. Para tales efectos se realizó una medición pre a las salidas académicas “CAMPAMENTO DE INNOVACION METODOLÓGICA EN RECREACIÓN CAMPING GUAYACANES” y “CAMPAMENTO DE ESTRATEGIAS DE EDUCACIÓN EXPERIENCIAL Y ECOAVENTURA TOLÚ” y una medición post de las mismas con el fin de comparar estadísticamente el efecto de las salidas académicas sobre las HHSS y de liderazgo y así poder cuantificar estadísticamente los resultados

NEW BUTYROLACTONE FROM A MARINE-DERIVED FUNGUS ASPERGILLUS SP

Indexación: Web of Science; ScieloFour compounds that belong to two structure types, namely dibenzylbutyrolactone and sesterterpenoids, were obtained from the extract of the strain Aspergillus sp. (2P-22), isolated from a marine sponge, Cliona chilensis. Among them, compound 1 was identified as new, namely butylrolactone-VI. The structures of these compounds were characterized on the basis of spectroscopic data. Biological activities of these fungal metabolites, are described.http://ref.scielo.org/kbf7v

China and Latin America: Mutual benefits or asymmetric relationship?

With China’s rapid growth, it is worth considering whether or not the country has challenged the United States, which for decades was the hegemonic power in much of Latin America. Posed in international studies, these questions are viewed from a Western perspective, arguably ethnocentric and universalist, which understands the international context as one of allies and enemies, center and periphery. Thus, it is difficult to understand a global rearrangement involving a non-Western actor. There seems to be no other way of understanding peaceful coexistence without involving the dominant and dominated relationship. Therefore, this paper seeks to explain whether a strategic relationship, fostered based on equal relationships for mutual benefit, is possible, without thinking about the soft or strong power notion that characterized the international order of the 20th Century. For the approach, a qualitative analytical-descriptive methodology is used

Girls Do Not Sweat: the Development of Gender Stereotypes in Physical Education in Primary School

Despite efforts towards gender equality, from an early age, girls practice sport less than boys. Explaining this is paramount to psychology. Stereotypes about gender-appropriate behaviour play a key role in doing physical-sports activity. Based on the expectancyvalue model, this study describes the gender beliefs of boys/girls regarding physical education. A total of 30 children (half-boys, half-girls) that were 4th- and 5th-year pupils (8–10 years) at two Colombian schools were interviewed using a semi-structured script focusing on open-ended questions. Interviews were recorded, transcribed and analysed. The results suggest gender differences in boys/girls already in the 4th year with respect to their abilities and the value they put on physical education based on a wide range of gender stereotypes. Specifically, boys/girls see football as a men’s sport, while skating, handball and volleyball are perceived as women’s sports. Furthermore, boys/girls have a dominant gender narrative that makes femininity subordinate to masculinity, thereby encouraging binary gender beliefs and practices. These stereotypes are reflected in their choice of activities and in how they use the school facilities, educing in this way the opportunities of both boys/girls as far as physical-sports activity are concerned. We discuss the findings emphasizing their relation to education and sociocultural influences. The conclusions suggest the need to make boys and girls more aware about gender equality, make changes to the activities and to how the physical spaces are used and provide equal teaching and learning experiences to reduce a divide still present in physical-sports education

Disfunción familiar como factor asociado a consumo de alcohol en adolescentes atendidos en el hospital regional docente de Trujillo

La presente investigación será de tipo analítico, observacional, retrospectivo y longitudinal se realizará en adolescentes que se atienden en el servicio de psiquiatría del Hospital Regional Docente de Trujillo, durante los meses Junio 2018 a Mayo 2019, con la finalidad de definir la asociación entre la disfunción familiar y el consumo de alcohol. La muestra estará constituida por 240 adolescentes, de ambos sexos, dividido en 120 casos y 120 controles, quienes cumplían con los siguientes criterios de inclusión: edad entre los 11 a 19 años, adolescentes que participen voluntariamente y cuyo padre, madre o tutor esté de acuerdo con participar en el estudio; a quienes se les aplicará el Test de AUDIT para determinar el tipo de consumo de alcohol, y el test de APGAR FAMILIAR para determinar la disfunción familiar. El tamaño de la muestra se determinó mediante el uso de la fórmula estadística para estudios de casos y controles. Se estableció la presencia de las variables en estudio en la ficha de recolección de datos, la cual fue llenada hasta completar los tamaños muestrales en ambos grupos de estudio. Con esta información se procederá a elaborar la base de datos y a realizar en análisis estadístico respectivo.Trabajo de investigació

Hiperuricemia como factor de riesgo para el desarrollo de preeclampsia

Determinar si la hiperuricemia es un factor de riesgo para el desarrollo de Preeclampsia en gestantes atendidas en el Hospital Belén de Trujillo periodo Enero 2013 – Diciembre 2013. Material y método: Se realizó un estudio retrospectivo, de casos y controles. Se revisaron 84 historias clínicas, seleccionadas al azar, de gestantes atendidas en el periodo comprendido entre Enero del 2013 hasta Diciembre del 2013. Se realizó una comparación entre el grupo de casos, formado por las gestantes con diagnóstico de Preeclampsia, y el grupo de controles, formado por las gestantes sin diagnóstico de Preeclampsia; evaluándose el valor de ácido úrico. Se calculó el Odds Ratio (OR) y sus respectivos intervalos de confianza (IC 95%) utilizando la prueba de Chi Cuadrado. Resultados: Al comparar ambos grupos se obtuvo como resultado un valor de p < 0,05, OR de 3,06 con un IC de 95% (1,18 – 8,86). Conclusión: En el Hospital Belén de Trujillo la hiperuricemia en gestantes es un factor de riesgo para el desarrollo de Preeclampsia.Determine if hyperuricemia is a risk factor for the development of preeclampsia in pregnant women at the Belen Hospital of Trujillo period January 2013 - December 2013. Methods: A retrospective study of cases and controls was conducted. I checked 84 clinical records randomly selected from pregnant women at the period from January 2013 to December 2013. Evaluating the value of uric acid, a comparison between the case group, formed by the pregnant women diagnosed with preeclampsia and the control group, consisting of the pregnant women without preeclampsia diagnosis was made. The Odds Ratio (OR) and confidence intervals (95% CI) using Chi Square test was calculated. Results: When comparing both groups was obtained as a result a value of P <0.05, OR 3.06 with 95% CI (1.18 to 8.86). Conclusion: In the Hospital Belen of Trujillo, hyperuricemia in pregnant is a risk factor for developing preeclampsiaTesi