The Large UV/Optical/IR Surveyor (LUVOIR) is one of four Astro2020 Decadal Survey Missions, a concept for `flag-ship' class space-borne observatory, operating across the multi-wavelength ...UV/Optical/NIR spectra. An Optical Telescope concept being considered is the segmented primary mirror architecture with composite backplane structure. In order to achieve the high-contrast imaging required to satisfy the primary science goals of this mission would require a pico-meter wavefront RMS stability over a wavefront control time step, a milli-Kelvin level thermometry sensing and control, and near-zero CTE materials. The LUVOIR primary mirror segment assemblies and composite backplane support structure require active thermal management to maintain operational temperature during flight operations. Furthermore, the active thermal control must be sufficiently stable to prevent time-varying thermally induced structure distortions to minimize optical aberrations. This paper describes a Thermal System Architecture of 2 concepts considered for the LUVOIR decadal study, and a systematic approach to developing a thermal architecture of modular composite sections of the mirror support structure and primary mirror segment assemblies.
The JWST Optical Telescope Element (OTE) assembly is the largest optically stable infrared-optimized telescope currently being manufactured and assembled, and is scheduled for launch in 2018. The ...JWST OTE, including the 18 segment primary mirror, secondary mirror, and the Aft Optics Subsystem (AOS) are designed to be passively cooled and operate near 45K. These optical elements are supported by a complex composite backplane structure. As a part of the structural distortion model validation efforts, a series of tests are planned during the cryogenic vacuum test of the fully integrated flight hardware at NASA JSC Chamber A. The successful ends to the thermal-distortion phases are heavily dependent on the accurate temperature knowledge of the OTE structural members. However, the current temperature sensor allocations during the cryo-vac test may not have sufficient fidelity to provide accurate knowledge of the temperature distributions within the composite structure. A method based on an inverse distance relationship among the sensors and thermal model nodes was developed to improve the thermal data provided for the nanometer scale WaveFront Error (WFE) predictions. The Linear Distance Weighted Interpolation (LDWI) method was developed to augment the thermal model predictions based on the sparse sensor information. This paper will encompass the development of the LDWI method using the test data from the earlier pathfinder cryo-vac tests, and the results of the notional and as tested WFE predictions from the structural finite element model cases to characterize the accuracies of this LDWI method.
The purpose of this study was to evaluate current infectious waste management practices in order to identify potential problem areas associated with currently utilized systems for handling these ...waste materials. The study was approached as two separate, but related, subproblems. Subproblem I examined information on categories of infectious waste generated by a variety of activities, procedures employed for managing these waste materials, and treatment/storage/disposal practices commonly used. In Subproblem II, issues dealing with regulatory control, worker and public health and safety, and infectious waste management practices were identified and evaluated. Information for the study was obtained through a mail survey of individuals involved in the management of infectious wastes and/or knowledgeable of potential hazards associated with these types of waste materials. Survey participants were categorized into the following groups: (1) state solid waste regulatory agencies; (2) medical/infectious waste generators/handlers from the health care industry; (3) medical/infectious waste generators/handlers from medical/biological research activities in the private, government, and academic sectors; (4) operators of private or municipal facilities which manage medical/infectious wastes; and, (5) individuals from other related activities. Data treatment consisted of descriptive analysis and simple percentages. The Chi Square Test was used to test for statistical significance between the relationship of infectious waste categories and the activity(ies) conducted and the extent of agreement on certain infectious waste practices among the survey participant groups. Infectious waste generators and managers did not differ to any great extent in practices utilized to handle these waste materials. Many of the elements which compose a waste management system (storage, waste segregation, transportation, treatment, and disposal) were utilized to some extent throughout the participant groups. A significant relationship between the types of infectious wastes generated and facility activities was not noted. However, agreement among the survey participants on infectious waste treatment and disposal methods was seen. Survey participant responses to issues dealing with regulatory control, occupational health and safety, public health and safety, and infectious waste management practices were evaluated. Several key issues representative of potential problem areas were examined in an effort to highlight areas where corrective actions are required.
Introduction Urban form characteristics intended to support pedestrian activity, collectively referred to as neighborhood walkability, are thought to increase total physical activity. However, little ...is known about how neighborhood walkability influences utilization of neighborhood space by residents and their overall physical activity. Methods Sociodemographic information and data on mobility and physical activity over 1-week periods measured by GPS loggers and accelerometers were collected from 803 residents of New York City between November 2010 and November 2011. Potentially accessible neighborhood areas were defined as land area within a 1-kilometer distance of the subject’s home (radial buffer) and within a 1-kilometer journey on the street network from the home (network buffer). To define actual areas utilized by subjects, a minimum convex polygon was plotted around GPS waypoints falling within 1 kilometer of the home. A neighborhood walkability scale was calculated for each neighborhood area. Data were analyzed in 2014. Results Total residential neighborhood space utilized by subjects was significantly associated with street intersection density and was significantly negatively associated with residential density and subway stop density within 1 kilometer of the home. Walkability scale scores were significantly higher within utilized as compared with non-utilized neighborhood areas. Neighborhood walkability in the utilized neighborhood area was positively associated with total weekly physical activity (32% 95% CI=17%, 49% more minutes of moderate-equivalent physical activity across the interquartile range of walkability). Conclusion Neighborhood walkability is associated with neighborhood spaces utilized by residents and total weekly physical activity.
HIV-1 replication within the central nervous system (CNS) impairs neurocognitive function and has the potential to establish persistent, compartmentalized viral reservoirs. The origins of HIV-1 ...detected in the CNS compartment are unknown, including whether cells within the cerebrospinal fluid (CSF) produce virus. We measured viral RNA+ cells in CSF from acutely infected macaques longitudinally and people living with early stages of acute HIV-1. Active viral transcription (spliced viral RNA) was present in CSF CD4+ T cells as early as four weeks post-SHIV infection, and among all acute HIV-1 specimens (N = 6; Fiebig III/IV). Replication-inactive CD4+ T cell infection, indicated by unspliced viral RNA in the absence of spliced viral RNA, was even more prevalent, present in CSF of >50% macaques and human CSF at ~10-fold higher frequency than productive infection. Infection levels were similar between CSF and peripheral blood (and lymph nodes in macaques), indicating comparable T cell infection across these compartments. In addition, surface markers of activation were increased on CSF T cells and monocytes and correlated with CSF soluble markers of inflammation. These studies provide direct evidence of HIV-1 replication in CD4+ T cells and broad immune activation in peripheral blood and the CNS during acute infection, likely contributing to early neuroinflammation and reservoir seeding. Thus, early initiation of antiretroviral therapy may not be able to prevent establishment of CNS viral reservoirs and sources of long-term inflammation, important targets for HIV-1 cure and therapeutic strategies.
We examine how online sociocultural context influences play experience in the popular online role‐playing game, World of Warcraft (WoW). We focus on how guilds, in‐game associations of like‐minded ...players, establish social relationships and cultural understandings that shape online play experience. Some guilds help their members regulate the stressful arousal emerging from challenging gaming activities—such as collaborative raids, where multiple players together try to defeat challenging opponents termed bosses—maximizing stress' positive eustressful potential. By contrast, so‐called “hard‐core” raiding guilds, the primary focus of this article, push their members to more extreme forms of online gaming, linking in‐game arousal with problematic patterns of play, potentially transforming pleasurable gaming eustress into harmful distress. Overall, we treat guilds as emergent communities of play, which, in the manner they differentially regulate their members’ gaming experiences, sharply illuminate the deep sociocultural shaping of the stress process. We suggest that these cultural processes are less visible in studies focusing more narrowly on distress or eustress alone—typically, medical anthropology in the first case, games studies in the second—making a balanced approach such as ours critical to psychological anthropologists hoping to clarify how culture lends psychobiological arousal its positive or negative valence.
Abstract
Information about the cognate pairing of TCR alpha-beta chains and BCR IgH and IgKL chains encoded by individual T and B cells is key to understanding adaptive immune responses and ...developing therapeutic applications. We have previously reported the development of a sensitive technology that allows the amplification and identification of the paired human TCR alpha and beta chains from single T cells, termed iPair-TCR. Here, we report the extension of this technology to identify paired human BCR IgH and IgKL chains from antigen-specific single B cells. In this proof of concept study, we identified paired-VDJ-receptors from antigen-specific B-cells from nine Pfs230-EPA immunized Malian adults using the iPair-BCR method. Next, we developed a method to rapidly generate Fab fragments and demonstrate the binding of several of these single cell targets to the original Pfs230 antigen. Single cells of interest were identified based upon their repeated frequency on the plate, which indicates a clonal selection. The corresponding heavy and light chains were PCR amplified from selected wells. Using overlap extension PCR, all necessary elements for in vitro transcription and translation and either the CH1 or C-kappa-domain were added to both the 5′ and 3′ ends of the single cell VDJ. After in vitro transcription and translation, four out of five tested Fab fragments demonstrated binding through a colorimetric ELISA assay. The overall process after VDJ identification can be performed in under a week indicating the utility of our technology for rapid identification of antigen-specific BCRs and functional binding characteristics.
PDF
