Smoking and Mortality Among US Astronauts

Astronauts have lower age-specific mortality risk than the U.S. general population from all natural causes of death, particularly cardiovascular disease and cancer. Yet, understanding if they are as healthy as their backgrounds predict they should be, requires that epidemiologists understand (and measure) all potentially confounding exposures in this cohort. Tobacco smoking prevalence has been measured in the U.S. astronaut cohort, but its impact on mortality has not been previously assessed. If smoking history has a negative impact on mortality, this could confound attempts to measure the relative health of astronauts

Silvabase: A flexible data file management system

The need for a more flexible and efficient data file management system for mission planning in the Mission Operations Laboratory (EO) at MSFC has spawned the development of Silvabase. Silvabase is a new data file structure based on a B+ tree data structure. This data organization allows for efficient forward and backward sequential reads, random searches, and appends to existing data. It also provides random insertions and deletions with reasonable efficiency, utilization of storage space well but not at the expense of speed, and performance of these functions on a large volume of data. Mission planners required that some data be keyed and manipulated in ways not found in a commercial product. Mission planning software is currently being converted to use Silvabase in the Spacelab and Space Station Mission Planning Systems. Silvabase runs on a Digital Equipment Corporation's popular VAX/VMS computers in VAX Fortran. Silvabase has unique features involving time histories and intervals such as in operations research. Because of its flexibility and unique capabilities, Silvabase could be used in almost any government or commercial application that requires efficient reads, searches, and appends in medium to large amounts of almost any kind of data

DMT and “The Man Box:” Provoking Change and Encouraging Authentic Living, An Arts-Based Project

This thesis explores the mind-body experience through an arts-based research approach to examine, and redefine the emotional capacity and usefulness of males through societal determinants that limits and hinders men from living their authentic selves. Through the lens of a metaphoric “Man Box” 112 men participated in a workshop recreating their personal narratives of socialization through, style of dress, coping mechanisms, belief systems and who they should be as men through society\u27s standards. In the “Man Box,” male bonding, and emotional feelings are discouraged, while the objectification of women, material property and physical/emotional strength are encouraged. This research investigates the mind-body approach as a positive shift to increase quality of life while decreasing symptoms of anxiety, depression, subjective well-being, poor mood, shame, and body image. Effects for sexual orientation were also explored, but due to the inconsistency of the information, the data remained inconclusive. Methodological shortcomings of more specific studies limited the results and, therefore, further investigations are needed to strengthen and expand upon art-based research in DMT, with the consideration of personal narrative and poetry as therapy. Information about the usefulness of the mind-body approach in practices, career choices and various aspects of life are discussed

An exploration of organizational behavior that affects California community colleges’ ability to remove sanctions and have accreditation reaffirmed

textAccreditation is a federally recognized review process of quality assurance in higher education and is intended to engage institutions in continuous efforts to improve quality. If a college does not receive a positive evaluation as a result of an accreditation review, its regional accrediting agency may impose a sanction until that time when the college can fix deficiencies identified during the evaluation process. In California, the number of public community colleges having a sanction imposed by the western region’s Accrediting Commission of Community and Junior Colleges (ACCJC) has increased since the turn of the century, rising from one college on sanction in 2003 to as many as 27 colleges on sanction in 2012. From 2008 through 2013, 70 of California’s 112 community colleges had experienced a sanction. Of those, 49 made recommended improvements and had their accreditation reaffirmed within two years. However, some colleges take longer to make improvements and to have the sanction lifted. Focusing on colleges that successfully removed a sanction, this study employed a qualitative research approach using multiple methods: a survey questionnaire and a multiple case study of two colleges. Accreditation Liaison Officers from eight colleges responded to the survey. Two colleges participated in the multiple case study in which administrators, managers, faculty, and classified staff were interviewed. Survey and interview participants were asked what they believed were the organizational behaviors and characteristics that contributed to their successful removal of the sanction. Findings indicate that successful colleges did not delay responding to the sanction; they organized human resources into work groups to accomplish tasks; they mapped out plans and created timelines for completion; they increased communication efforts across campus; they involved many persons from their multiple constituent groups; and they documented all work and accomplishments. Findings also indicate that leaders at successful colleges are effective communicators and organizers; value the accreditation process; exhibit trust, respect, and openness, and work collaboratively and collegially. The findings in this study may provide helpful information to sanctioned colleges in the future.Educational Administratio

Proxy Functions and Inscrutability of Reference

Objection to Quine's argument for the inscrutability of reference. The proxy functions don't preserve the relations to experience, contrary to Quine's claims

Cancer gets physical: understanding how the tumor microenvironment contributes to tumor progression

An abnormal multicellular architecture and a stiffened extracellular matrix (ECM) are defining characteristics of breast cancer, and yet, most in vitro tumor models fail to recapitulate the aberrant tumor microenvironment or accurately predict in vivo cellular responses to therapeutics. This dissertation aims to fill this gap in knowledge by developing and applying a suite of novel in vitro tools to investigate how the physical properties of the tumor microenvironment drive cancer progression. Our approach to develop and apply in vitro tools rests on three independent, but synergistic pillars. First, we established a 3D in vitro tumor model that mimics critical cell-cell and cell-ECM interactions by embedding multicellular spheroids within 3D collagen matrices. We assessed the in vivo relevance of our 3D collagen embedded spheroid model by quantifying the presence of highly malignant cancer stem cells (CSCs) before and after chemotherapeutic treatment with either paclitaxel or cisplatin. By characterizing the CSC response within two other commonly used in vitro models—a 2D monolayer and a 3D collagen model in which single cells are diffusely embedded—we found the CSC response to be model-dependent. Our results therefore highlight the need to screen potential CSC-specific chemotherapy drugs within in vitro models that recapitulate the in vivo 3D multicellular tumor architecture. Second, through integrating computational and experimental approaches, we developed a mathematical model of the transcriptional regulators—Yes-associated protein (YAP) and transcriptional co-activator with PDZ-binding motif (TAZ)—which are often overactive in late-stage cancers despite mutations within their upstream signaling pathway being rare. Here, dysregulated cytoskeletal tension and disrupted apical-basal polarity, two defining characteristics of breast cancer, have been suggested to promote overactive YAP/TAZ signaling. Therefore, we developed a computational model to study how overactive cytoskeletal tension, due to increased ECM stiffness, leads to aberrant YAP/TAZ signaling in cancer. The model revealed that simultaneous alterations in cell mechanics and cell-cell adhesion signaling synergistically converge on YAP/TAZ activity and lead to its overactivation, a process poorly understood in cancer progression. Finally, in an effort to decouple the effects of collagen fiber density and network mechanics on cancer cell behavior, we developed a highly tunable in vitro 3D interpenetrating network (IPN) platform consisting of a primary collagen network reinforced by a secondary visible-light-mediated thiol-ene PEG network. The IPN platform is cytocompatible, inherently bioactive, and mechanically tunable, which makes it a useful tool for studying mechanotransductive signaling pathways. Moreover, while this thesis work focused on in vitro applications, our approach raises the interesting possibility of altering the physical properties of the tumor microenvironment as a potential therapeutic. In summary, this work addresses the question of how the physical properties of the tumor microenvironment affect cancer progression by deploying three distinct, but complementary approaches, and suggests that addressing the physical aspects of cancer progression may improve clinical outcomes.2020-02-20T00:00:00

Simulations of MHD Instabilities in Intracluster Medium Including Anisotropic Thermal Conduction

We perform a suite of simulations of cooling cores in clusters of galaxies in order to investigate the effect of the recently discovered heat flux buoyancy instability (HBI) on the evolution of cores. Our models follow the 3-dimensional magnetohydrodynamics (MHD) of cooling cluster cores and capture the effects of anisotropic heat conduction along the lines of magnetic field, but do not account for the cosmological setting of clusters or the presence of AGN. Our model clusters can be divided into three groups according to their final thermodynamical state: catastrophically collapsing cores, isothermal cores, and an intermediate group whose final state is determined by the initial configuration of magnetic field. Modeled cores that are reminiscent of real cluster cores show evolution towards thermal collapse on a time scale which is prolonged by a factor of ~2-10 compared with the zero-conduction cases. The principal effect of the HBI is to re-orient field lines to be perpendicular to the temperature gradient. Once the field has been wrapped up onto spherical surfaces surrounding the core, the core is insulated from further conductive heating (with the effective thermal conduction suppressed to less than 1/100th of the Spitzer value) and proceeds to collapse. We speculate that, in real clusters, the central AGN and possibly mergers play the role of "stirrers," periodically disrupting the azimuthal field structure and allowing thermal conduction to sporadically heat the core.Comment: 16 pages, 3 tables, 17 figures, accepted to ApJ with minor revisions, to appear in Volume 704, Oct 20, 2009 issu