Higher-order Lorentz-invariance violation, quantum gravity and fine-tuning

The issue of Lorentz fine-tuning in effective theories containing higher-order operators is studied. To this end, we focus on the Myers-Pospelov extension of QED with dimension-five operators in the photon sector and standard fermions. We compute the fermion self-energy at one-loop order considering its even and odd $CPT$ contributions. In the even sector we find small radiative corrections to the usual parameters of QED which also turn to be finite. In the odd sector the axial operator is shown to contain unsuppressed effects of Lorentz violation leading to a possible fine-tuning. We use dimensional regularization to deal with the divergencies and a generic preferred four-vector. Taking the first steps in the renormalization procedure for Lorentz violating theories we arrive to acceptable small corrections allowing to set the bound $\xi<6 \times10^{-3}$.Comment: 11 pages, new version with the correct pole extractio

Polymer quantization, stability and higher-order time derivative terms

The stability of higher-order time derivative theories using the polymer extension of quantum mechanics is studied. First, we focus on the well-known Pais-Uhlenbeck model and by casting the theory into the sum of two decoupled The possibility that fundamental discreteness implicit in a quantum gravity theory may act as a natural regulator for ultraviolet singularities arising in quantum field theory has been intensively studied. Here, along the same expectations, we investigate whether a nonstandard representation, called polymer representation can smooth away the large amount of negative energy that afflicts the Hamiltonians of higher-order time derivative theories; rendering the theory unstable when interactions come into play. We focus on the fourth-order Pais-Uhlenbeck model which can be reexpressed as the sum of two decoupled harmonic oscillators one producing positive energy and the other negative energy. As expected, the Schrodinger quantization of such model leads to the stability problem or to negative norm states called ghosts. Within the framework of polymer quantization we show the existence of new regions where the Hamiltonian can be defined well bounded from below.Comment: 13 pages, 2 figure

Helping the Helpers: Altruism As A Rational Choice of Donors to A Students Voluntary Organization

Altruism, understood as the individual disposition to sacrifice personal income to improve someone else´s income can be a rational choice strategy which responds to different motivations, incentives and institutions, in a consistent way with the donor´s optimization logic. In this article we extend the Andreoni and Miller´s experimental design (2002) using a modified Dictator game and we applied it to 470 students from several universities and different majors, years of study and level of income who can donate part of their income to the Bella Flor Foundation (http://www.bellaflor.org/), a real nonprofit organization founded by a group of college students whose mission is to promote the integral development of the children from Bella Flor, Paraíso and Mirador neighborhoods through social activities in education, health care, recreation, and exalting human values". We test the consistency of the player´s decisions with the axioms of revealed preferences, and with the effects of relative prices and income. We also evaluate the violation of consistency of the axioms and estimate the demand functions for altruism towards this charity, with policy implications related to the optimal design for fundraising strategies. Our results confirm that a significant fraction of individuals show consistent decisions, i.e. that donations to these charities behave as "normal goods" in price and income effects and with rather small number of violations of the axioms of revealed preferences. However, the experimental data suggests that revealing the identity of the donor can decrease altruism and induce more violations of the axioms of consistent behavior mentioned."altruism, experimental economics, consistency, GARP, Charity, dictator game, Bella Flor.

Endoscopic Repair of Frontal Sinus Cerebrospinal Fluid Leaks after Firearm Injuries: Report of Two Cases

Objectives To describe two cases of cerebrospinal fluid (CSF) leak repair after gunshot wound to the head.Design Retrospective review of two cases.Settings A large regional tertiary care facility.Participants Two patients with gunshot wounds to the skull base.Main Outcome Measures Preoperative and postoperative physical and radiologic findings.Results Patients in this series underwent endoscopic surgery, debridement, and repair of CSF leaks after gunshot wounds to the head. To date, the patients are without CSF leak.Conclusions Endoscopic closure of anterior skull base CSF leaks in patients with gunshot wounds can be safe and effective. Treatment should be decided by the severity of neurologic deterioration throughout the emergency period and the existence or absence of associated intracranial lesions. Timing for surgery should be decided with great care and with a multidisciplinary approach

Diseño de galgas extensométricas lineales a escala de micras para la reducción de factores externos existentes en la industria M.E.M.S.

Auxiliar de InvestigaciónEn la industria en general (ej. industria aeronáutica), es muy importante poder llegar a la obtención de un sistema de medición, que mantenga un monitoreo continuo de las diversas partes mecánicas. Debido a esta situación, aparecen las galgas extensométricas como una solución al tema de monitoreo, ya que este tipo de dispositivos pueden obtener mediciones precisas de las variaciones de los parámetros (como es el caso de las deformaciones que sufren los componentes mecánicos) y en el caso más extremo, se puede lograr detectar a tiempo posibles rupturas en dichos componentes. Teniendo esto como precedente, las galgas extensométricas se definen como un transductor basado en el principio extensométrico, el cual, al ser sometido a algún efecto mecánico (ej. tensión, presión, etc.) varia su resistencia, siendo capaz de convertir pequeñas deformaciones de un material en medidas cuantificables. Por otra parte, la fabricación y la miniaturización de las galgas extensométricas han presentado un visible avance, ya que el impacto que han tenido este tipo de transductores en los diferentes campos (ej. la mecánica) ha aportado una mejora en control de las deformaciones. Entre tanto, para realizar la miniaturización de una galga extensométrica se usa tecnología M.E.M.S (por sus siglas en inglés Microelectromechanical systems), que brinda una disminución en el consumo de potencia, alto desempeño, menor peso y un costo más bajo de fabricación, en comparación con otros dispositivos.INTRODUCCIÓN 1. ANTECEDENTES 2. JUSTIFICACIÓN 3. PLANTEAMIENTO DEL PROBLEMA 4. MARCO DE REFERENCIA 5. OBJETIVOS 6. ALCANCES Y LIMITACIONES 7. METODOLOGÍA 8. CRONOGRAMA DE ACTIVIDADES 9. ANÁLISIS DE RESULTADOS 10. TRABAJOS FUTUROS 11. CONCLUSIONES BIBLIOGRAFÍA ANEXOSPregradoIngeniero Electrónic

La Sinfonía Nº4 de Gustav Mahler : análisis, preparación y presentación en concierto

El presente trabajo contiene en formato de video las memorias del concierto: Sinfonía N°4 de Gustav Mahler y el análisis musical de la sinfonía. Fue producido y editado por el director de la Orquesta, Maestro Camilo Bustamante Reyes. El concierto se realizó el día 22 de Julio de 2017 en el Auditorio Fabio Lozano de la Universidad Jorge Tadeo de Bogotá. A través de la “Residencia Gustav Mahler” fue conformada una Orquesta para este concierto. Hicieron parte de este proyecto músicos colombianos y venezolanos de la Universidad Nacional, Javeriana, Corpas, Andes, Central, el Bosque, Conservatorio del Tolima, Orquesta Filarmónica de Bogotá, Orquesta Sinfónica de Colombia, Orquesta Simón Bolivar, Nueva Filarmonía, Batuta, Bogotá Chamber Orchestra, FJC, OFJ.This work contains in video format the memories of the concert: Gustav Mahler's Symphony No. 4 and the musical analysis of the symphony. It was produced and edited by the conductor of the Orchestra, Maestro Camilo Bustamante Reyes. The concert was held on July 22, 2017 at the Fabio Lozano Auditorium of the Universidad Jorge Tadeo in Bogotá. Through the "Gustav Mahler Residence" an Orchestra was formed for this concert. Colombian and Venezuelan musicians integrated this project from the Universidad Nacional, Javeriana, Corpas, Andes, Central, el Bosque, Conservatorio del Tolima, Orquesta Filarmónica de Bogotá, Orquesta Sinfónica de Colombia, Orquesta Simón Bolivar, Nueva Filarmonía, Batuta, Bogotá Chamber Orchestra, FJC, OFJ.Magíster en MúsicaMaestrí

El principio de necesidad de la pena en el Estado social y democrático de derecho

La presente investigación fija el contenido, el alcance y las aplicaciones prácticas del principio de necesidad de la pena restrictiva de la libertad en un esquema garantista y minimalista del derecho penal, el cual debe corresponder a un Estado social y democrático de derecho fundado en el respeto a la dignidad humana. A la luz de esa prefiguración constitucional del Estado, la finalidad, instrumentalización y necesidad de la pena deben condicionarse primordialmente en función del crecimiento, la reeducación y la reinserción social del penado, como ser humano. Así mismo, se cuestionan tanto la evolución como las decisiones desde el derecho internacional y la jurisprudencia nacional en lo concerniente a la imposición de sanciones penales privativas de la libertad (aunque en mi criterio debe hablarse de sanciones “restrictivas” y no “privativas” de la libertad), para establecer los límites del Estado como agente represor, y precisar las coherencias o incoherencias de nuestra política criminal y de la labor hermenéutica de los jueces en la determinación, imposición y ejecución de la pena, según sea el caso. De lo anterior deriva la importancia del principio de necesidad de la pena que ha presentado diferentes acepciones, pero que, en últimas, consiste en el diagnóstico y pronóstico de la eventual posibilidad de reiteración de la conducta delictiva, a partir del reconocimiento del sujeto individual y de sus derechos como miembro partícipe de la sociedad. Se trata, entonces, de cuestionar y proponer, desde la política criminal, y para el ejercicio hermenéutico garantista por parte de los jueces, los elementos necesarios para que la consecuencia jurídico-penal, que la mayoría de las veces deriva en la restricción de la libertad, pueda tener otras opciones y que en últimas se aplique de acuerdo con el modelo de Estado planteado en la Constitución, esto es, en sintonía con un enfoque social y democrático de derecho, en el marco del respeto de la dignidad humana.Universidad Libre – Facultad de Derecho – Doctorado en DerechoThis research establishes the content, scope and practical applications of the principle of necessity of the restriction of liberty in a guaranteeist and minimalist scheme of criminal law, which must correspond to a social and democratic state of law founded on respect for human dignity. In light of this constitutional prefiguration of the State, the purpose, instrumentalization and necessity of the penalty must be conditioned primarily on the basis of growth, reeducation and social reintegration of the prisoner, as a human being. Likewise, both the evolution and the decisions from international law and national jurisprudence regarding the imposition of penal sanctions depriving liberty are questioned (although in my opinion it should be spoken of "restrictive" and not "privative" sanctions of freedom), to establish the limits of the State as a repressive agent, and specify the coherence or inconsistency of our criminal policy and the hermeneutical work of the judges in the determination, imposition and execution of the sentence, as the case may be. From the foregoing derives the importance of the principle of necessity of the penalty that has presented different meanings, but which, ultimately, consists of the diagnosis and prognosis of the possible possibility of repetition of the criminal behavior, based on the recognition of the individual subject and of their rights as a participating member of society. It is a matter, then, of questioning and proposing, from the criminal policy, and for the hermeneutic exercise of guarantees by the judges, the elements necessary for the legal-criminal consequence, which most of the time results in the restriction of the freedom, may have other options and that it is ultimately applied in accordance with the State model established in the Constitution, that is, in tune with a social and democratic approach to law, within the framework of respect for human dignity

Computational search for UV radiation resistance strategies in Deinococcus swuensis isolated from Paramo ecosystems

Ultraviolet radiation (UVR) is widely known as deleterious for many organisms since it can cause damage to biomolecules either directly or indirectly via the formation of reactive oxygen species. The goal of this study was to analyze the capacity of high-mountain Espeletia hartwegiana plant phyllosphere microorganisms to survive UVR and to identify genes related to resistance strategies. A strain of Deinococcus swuensis showed a high survival rate of up to 60% after UVR treatment at 800J/m2 and was used for differential expression analysis using RNA-seq after exposing cells to 400J/m2 of UVR (with \u3e95% survival rate). Differentially expressed genes were identified using the R-Bioconductor package NOISeq and compared with other reported resistance strategies reported for this genus. Genes identified as being overexpressed included transcriptional regulators and genes involved in protection against damage by UVR. Non-coding (nc)RNAs were also differentially expressed, some of which have not been previously implicated. This study characterized the immediate radiation response of D. swuensis and indicates the involvement of ncRNAs in the adaptation to extreme environmental conditions

Compensatory Cognitive Training for Latino Youth at Clinical High Risk for Psychosis: Study Protocol for a Randomized Controlled Trial.

Background: Early psychosocial interventions targeting cognitive and functional outcomes in individuals at clinical high risk for psychosis are a research priority. An even greater need is the identification of effective interventions in underserved populations. Compensatory Cognitive Training (CCT) is a psychosocial intervention with demonstrated efficacy in chronic schizophrenia and first episode psychosis, but remains to be evaluated in pre-illness phases. The aim of this study was to describe the development and implementation of an ongoing pilot randomized controlled trial investigating the efficacy of group-based, manualized CCT, as compared to recreational therapy (RT), for Latino participants at clinical high risk for psychosis (CHR) in both the United States and Mexico. It is hypothesized that, in comparison to those receiving RT, participants receiving CCT will show significant improvements in neurocognitive performance and functional capacity (co-primary outcomes) and self-rated functioning and clinical symptoms (secondary outcomes). Methods: Latino CHR participants aged 12-30 years will be included in the study. Both CCT and RT will be delivered in either Spanish or English, depending on group preference. Additionally, all assessments will be administered in participants' preferred language. A comprehensive assessment of neurocognitive and functional performance and clinical symptomatology will be performed at baseline, mid-intervention (4 weeks, 8 weeks), post-intervention (12 weeks) and 3-month follow-up. The primary outcome measures are neurocognition and functional capacity, as assessed by the MATRICS (Measurement and Treatment Research in Cognition in Schizophrenia) Consensus Cognitive Battery and the University of California, San Diego Performance-Based Skills Assessment-Brief, respectively. Furthermore, secondary outcomes measures will be used to examine change in clinical symptoms and self-reported functioning in response to CCT versus RT. Discussion: The evaluation of a novel treatment such as CCT in CHR youth will provide empirical support for a low risk, comprehensive cognitive intervention that could have important implications for public health if it improves neurocognition and functioning