Electrophoresis of positioned nucleosomes

We present in this paper an original approach to compute the electrophoretic mobility of rigid nucleo-protein complexes like nucleosomes. This model allows to address theoretically the influence of complex position along DNA, as well as wrapped length of DNA on the electrophoretic mobility of the complex. The predictions of the model are in qualitative agreement with experimental results on mononucleosomes assembled on short DNA fragments (<400bp). Influence of additional experimental parameters like gel concentration, ionic strength, effective charges is also discussed in the framework of the model, and is found to be qualitatively consistent with experiments when available. Based on the present model, we propose a simple semi-empirical formula describing positioning of nucleosomes as seen through electrophoresis.Comment: to appear in Biophys. J. 29 page

Phenotypic and functional analysis of positive selection in the gamma/delta T cell lineage.

Recent evidence suggests that T cells expressing gamma/delta antigen receptors (T cell receptor [TCR]) are subject to positive selection during development. We have shown that T cells expressing a class I major histocompatibility complex (MHC)-specific gamma/delta TCR transgene (tg) are not positively selected in class I MHC-deficient, beta 2-microglobulin (beta 2m) gene knockout mice (tg+ beta 2m-). In this report, we examine phenotypic and functional parameters of gamma/delta positive selection in this transgenic model system. TCR-gamma/delta tg+ thymocytes of mature surface phenotype (heat stable antigen-, CD5hi) were found in beta 2m+ but not in beta 2m- mice. Moreover, subsets of tg+ thymocytes with the phenotype of activated T cells (interleukin [IL]2R+, CD44hi, or Mel-14lo) were also present only in the beta 2m+ mice. Cyclosporine A, which blocks positive selection of TCR-alpha/beta T cells, also inhibited gamma/delta tg+ T cell development. These results support the idea that positive selection of TCR-gamma/delta requires active TCR-mediated signal transduction. Whereas tg+ beta 2m+ thymocytes produced IL-2 and proliferated when stimulated by alloantigen, TCR engagement of tg+ beta 2m- thymocytes by antigen induced IL-2R expression but was uncoupled from the signal transduction pathway leading to IL-2 production and autocrine proliferation. Overall, these results demonstrate significant parallels between gamma/delta and alpha/beta lineage development, and suggest a general role for TCR signaling in thymic maturation

Princes, Thieves and Death: The Making of Heroes amongst the Yezidis of Armenia

This is the author accepted manuscript. The final version is available from JSTOR via the DOI in this record.This chapter discusses for the first time the production of heroic paradigms among the Kurmanji Kurdish-speaking Yezidis of Armenia and adds to the existing literature on masculinities in the Middle East and the former Soviet Union, using an approach derived from the ethnography of speaking. It identifies ciwanmêrî, a ‘traditional’ paradigm resembling the classical ‘princely virtues’ and identifies a newer contemporary paradigm coming from the post-Soviet ‘thieves in law’ model. It is not the values themselves, but the enactment of heroic feelings through the specific speech genre of kilamê ser which produces the heroes

Red Breast Syndrome and Acellular Dermal Matrix

Increasingly popular for use in breast reconstruction, acellular dermal matrix (ADM) can provide support and protection to implants. However, use of ADM may be associated with infection and complications, including red breast syndrome (RBS). RBS is an inflammatory event that typically presents with cutaneous erythema over the domain where the ADM is surgically implanted. As ADM use increases, presumably, more cases of RBS will occur. Thus, techniques and tools to mitigate or manage RBS are needed to improve patient outcomes. Here, we describe a case where RBS was diagnosed and interestingly resolved after exchange for a different brand of dermal matrix. This surgical resolution maintained excellent reconstructive results with no recurrent erythema over a follow-up period of 7 months. Although we cannot rule out RBS due to other variables, RBS due to patient hypersensitivity to certain ADMs has been documented in the literature. In this instance, our results suggest that revision with an alternate ADM brand may serve as a potential solution

Informe de Experiencia en el área de Psicología Educativa

El presente informe tiene como finalidad describir los logros de aprendizaje y competencias (i.e. diagnostica, interviene y evalúa) alcanzadas durante el periodo de práctica preprofesional en dos centros educativos de Lima Metropolitana. De esta manera, se identificaron las principales necesidades de las instituciones a través de técnicas pertinentes, considerando la coyuntura y la población, para el posterior planteamiento de conclusiones y propuestas de mejora. Entre las técnicas empleadas se encuentran la observación de conducta, entrevistas y administración de pruebas psicológicas y cuestionarios. Estas permitieron identificar que los principales problemas de la población surgieron a partir de la pandemia; por ejemplo, necesidad de mejorar la capacidad de adaptación, convivencia en el hogar, empatía con familiares, resiliencia, regulación de emociones, entre otros. Es así como, en base a lo recogido, se desarrollaron intervenciones con padres de familia, estudiantes y docentes, la mayoría de ellas, talleres psicoeducativos enfocados en promoción o prevención, y desarrollados a partir del modelo psicométrico y constructivista. Si bien ambos modelos parten de enfoques distintos, complementándose permitieron un trabajo completo y transversal. En cuanto al plan de evaluación de las intervenciones, solo se pudieron desarrollar entrevistas telefónicas ya que la población no tenía los recursos suficientes como para hacer alguna evaluación que consigne internet o datos móviles. Sin embargo, se pudo reconocer que todos los talleres realizados propiciaron una mejora u optimización en los estudiantes y padres de familia, según lo reportado.The aim of this report is to describe the learning achievements and competencies (i.e. diagnoses, intervenes and evaluates) achieved during the pre-professional practice period in two educational centers in Lima Metropolitana. In this way, the main needs of the institutions were identified through relevant techniques, considering the situation and the population, for the subsequent approach to conclusions and proposals for improvement. Among the techniques used are behavior observation, interviews, and administration of psychological tests and questionnaires. These made it possible to identify that the main problems of the population arose from the pandemic; for example, the need for better adaptability, coexistence at home, empathy with family members, resilience, emotional regulation, among others. This is how, based on what was collected, interventions were developed with parents, students and teachers, most of them, psychoeducational workshops focused on promotion or prevention, and developed from the psychometric and constructivist model. Although both models start from different approaches, complementing each other they allowed a complete and transversal work. Regarding the intervention evaluation plan, only telephone interviews could be carried out since the population did not have sufficient resources to carry out an evaluation that includes internet or mobile data. However, it was possible to recognize that all the workshops carried out led to an improvement or optimization in the students and parents, as reported

Percepción de comportamientos interpersonales, necesidades psicológicas básicas, bienestar y satisfacción deportiva

A partir de la Teoría de la Autodeterminación, la presente investigación buscó explorar la relación entre los comportamientos interpersonales de los entrenadores, las necesidades psicológicas básicas, el bienestar y la satisfacción deportiva en un grupo de 228 deportistas universitarios (18 – 29 años) de Lima Metropolitana. Además, se buscó estudiar las propiedades psicométricas (i.e. validez factorial y confiabilidad) de los instrumentos utilizados. Para ello, se emplearon los siguientes instrumentos: (1) Cuestionario de Comportamientos Interpersonales en el Deporte, (2) Escala de Satisfacción Deportiva, (3) Escala de Satisfacción y Frustración de las Necesidades Psicológicas Básicas y (4) Escala de Afecto Positivo y Negativo-forma corta. Se halló que la percepción de apoyo a las NPB se asoció negativamente con la obstaculización a las NPB. Asimismo, la satisfacción de las NPB se relacionó negativamente con la con frustración de las NPB. Además, el afecto positivo se asoció negativamente con afecto negativo. En el análisis de senderos, se encontró que el apoyo percibo a las NPB se relaciona indirectamente con la satisfacción deportiva, teniendo la satisfacción de las NPB como variable mediadora. No obstante, también se halló una relación directa entre apoyo a las NPB y satisfacción deportiva. Por otro lado, se encontró una relación indirecta entre la obstaculización percibida a las NPB y el afecto negativo, teniendo como variable mediadora a la frustración de las NP

The meaning of parenteral hydration to family caregivers and patients with advanced cancer receiving hospice care.

CONTEXT: In the U.S., patients with advanced cancer who are dehydrated or have decreased oral intake almost always receive parenteral hydration in acute care facilities but rarely in the hospice setting. OBJECTIVES: To describe the meaning of hydration for terminally ill cancer patients in home hospice care and for their primary caregivers. METHODS: Phenomenological interviews were conducted at two time points with 85 patients and 84 caregivers enrolled in a randomized, double-blind, controlled trial examining the efficacy of parenteral hydration in patients with advanced cancer receiving hospice care in the southern U.S. Transcripts were analyzed hermeneutically by the interdisciplinary research team until consensus on the theme labels was reached. RESULTS: Patients and their family caregivers saw hydration as meaning hope and comfort. Hope was the view that hydration might prolong a life of dignity and enhance quality of life by reducing symptoms such as fatigue and increasing patients\u27 alertness. Patients and caregivers also described hydration as improving patients\u27 comfort by reducing pain; enhancing the effectiveness of pain medication; and nourishing the body, mind, and spirit. CONCLUSION: These findings differ from traditional hospice beliefs that dehydration enhances patient comfort, given that patients and their families in the study viewed fluids as enhancing comfort, dignity, and quality of life. Discussion with patients and families about their preferences for hydration may help tailor care plans to meet specific patient needs

The divergence time of protein structures modelled by Markov matrices and its relation to the divergence of sequences

A complete time-parameterized statistical model quantifying the divergent evolution of protein structures in terms of the patterns of conservation of their secondary structures is inferred from a large collection of protein 3D structure alignments. This provides a better alternative to time-parameterized sequence-based models of protein relatedness, that have clear limitations dealing with twilight and midnight zones of sequence relationships. Since protein structures are far more conserved due to the selection pressure directly placed on their function, divergence time estimates can be more accurate when inferred from structures. We use the Bayesian and information-theoretic framework of Minimum Message Length to infer a time-parameterized stochastic matrix (accounting for perturbed structural states of related residues) and associated Dirichlet models (accounting for insertions and deletions during the evolution of protein domains). These are used in concert to estimate the Markov time of divergence of tertiary structures, a task previously only possible using proxies (like RMSD). By analyzing one million pairs of homologous structures, we yield a relationship between the Markov divergence time of structures and of sequences. Using these inferred models and the relationship between the divergence of sequences and structures, we demonstrate a competitive performance in secondary structure prediction against neural network architectures commonly employed for this task. The source code and supplementary information are downloadable from \url{http://lcb.infotech.monash.edu.au/sstsum}.Comment: 12 pages, 6 figure