Fatigue, shift work characteristics, and occupational injury and illness in emergency medical services

The relationship between work scheduling, fatigue, and risk of injury and illness among Emergency Medical Services (EMS) workers is not well understood. Evidence in other settings suggests that work duration contributes to fatigue and increases the risk of accidents and occupational injuries. Rates of occupational injury are high. Extended shifts and overtime hours are common. Workers often report fatigue and poor sleep quality. Evidence is needed to inform policy-making and promote safety. Shift schedules and occupational injury and illness reports were obtained for 14 EMS agencies over a three-year period. The cohort contained 966,082 shifts, 4,382 employees, and 950 total injuries. Analyses examined the association between shift length, weekly work hours, crewmember familiarity, and occupational injury and illness. An increased risk of occupational injury and illness was hypothesized for individual shifts >8 hours and ≥48 weekly work hours. The proposed mechanism for increased risk was on-shift fatigue. A systematic literature review was performed to better understand differences in prior estimates of fatigue in EMS by methodologic approach. Risk of occupational injury and illness was increased for shifts >8 & ≤12 hours (RR 1.43; 95% CI 1.04-1.97), shifts >12 & ≤16 hours (RR 1.82; 95% CI 1.17-2.82), and shifts >16 and ≤24 hours (RR 2.29; 95% CI 1.52-3.46), compared to shifts ≤8 hours in duration. There was no increase in risk of occupational illness or injury with increasing weekly work hours. Crewmember familiarity was not associated with the outcome. Nightshift work was protective. Shift length is associated with occupational injury and illness in this cohort. As shift length increases, the risk of workplace injury and illness increases. These findings are based on observational data and are not generalizable to all EMS agencies. Evidence should be used to justify comprehensive prospective study. These projects are significant to public health. Calls for research were addressed from the National Occupational Research Agenda and the National EMS Advisory Council, government bodies who identified gaps in the knowledge of these issues. These data may serve as a foundation for future studies to inform decision-making at EMS agencies nationally and protect the health of the EMS workforce

Crew Endurance Training Program for the US Navy

Prepared for: Naval Advanced Medical Development Program; Naval Medical Research Center; 503 Robert Grant Avenue, Silver Spring, MD 20910The Crew Endurance Training program was designed to provide fleet-wide support to the US Navy on the successful implementation of circadian-based watchbills, and guidance on sleep management and crew endurance best practices. The first phase of the study included the evaluation of existing educational programs and the analysis of training needs. Combining information from studies conducted by the Naval Postgraduate School Crew Endurance team on USN ships, the expertise of the Sleep Matters Initiative (SMI), and feedback from active-duty service members (ADSMs), we developed the first version of training materials in 2019. The second phase of the project included the delivery of the training program, its assessment, and the analysis and refinement of the training. This iterative procedure was repeated throughout the second phase of the project. The training was provided to more than 1,160 ADSMs, both USN Sailors and Marines. Overall, the responses from all audiences were positive with a high level of satisfaction with the training provided in terms of understanding the importance of sleep, sleep hygiene practices, the effect of sleep on operational performance and endurance, how best to implement circadian-based watchbills, and with the instructors, course content, and training duration. In general, trainees asked for more in-depth information, but operational commitments limited the time available to answer all questions. Also, we updated the Crew Endurance website to support sharing of lessons learned and best practices for the individual and the command. The website includes references, tools, and training materials for use by the warfighter and shipboard leaders, as well as templates for shipboard watchbills and instructions to support circadian-based watchbills. Based on the findings from this study and the expressed need for training on crew endurance and guidance regarding the efficient application of circadian-based watchbills, we recommend the continuation of the Crew Endurance Training project.Naval Advanced Medical Development Program; Naval Medical Research CenterNaval Advanced Medical Development ProgramApproved for public release; distribution is unlimited

An injectable bone marrow-like scaffold enhances T cell immunity after hematopoietic stem cell transplantation.

Allogeneic hematopoietic stem cell transplantation (HSCT) is a curative treatment for multiple disorders, but deficiency and dysregulation of T cells limit its utility. Here we report a biomaterial-based scaffold that mimics features of T cell lymphopoiesis in the bone marrow. The bone marrow cryogel (BMC) releases bone morphogenetic protein-2 to recruit stromal cells and presents the Notch ligand Delta-like ligand-4 to facilitate T cell lineage specification of mouse and human hematopoietic progenitor cells. BMCs subcutaneously injected in mice at the time of HSCT enhanced T cell progenitor seeding of the thymus, T cell neogenesis and diversification of the T cell receptor repertoire. Peripheral T cell reconstitution increased ~6-fold in mouse HSCT and ~2-fold in human xenogeneic HSCT. Furthermore, BMCs promoted donor CD4+ regulatory T cell generation and improved survival after allogeneic HSCT. In comparison to adoptive transfer of T cell progenitors, BMCs increased donor chimerism, T cell generation and antigen-specific T cell responses to vaccination. BMCs may provide an off-the-shelf approach for enhancing T cell regeneration and mitigating graft-versus-host disease in HSCT

ASCA Observations of the Starburst-Driven Superwind Galaxy NGC 2146: Broad Band (0.6 - 9 keV) Spectral Properties

We report ASCA GIS and SIS observations of the nearby (D = 11.6 Mpc), nearly edge-on, starburst galaxy NGC 2146. These X-ray spectral data complement ROSAT PSPC and HRI imaging discussed by Armus et al., 1995. The broad band (0.6-9 keV) X-ray spectrum of NGC 2146 is best described by a two component model: the soft X-ray emission with a Raymond-Smith thermal plasma model having a temperature of kT $\sim 0.8$ keV; the hard X-ray emission with a thermal plasma model having kT $\sim 8$ keV or a power-law model having a photon index of $\sim 1.7$. We do not find compelling evidence of substantial excess absorption above the Galactic value. The soft (hard) thermal component provides about 30% (70%) of the total luminosity in the 0.5 - 2.0 keV energy band, while in the 2-10 keV energy range only the hard component plays a major role. The spectral results allow us to set tighter constraints on the starburst-driven superwind model, which we show can satisfactorily account for the luminosity, mass, and energy content represented by the soft X-ray spectral component. We estimate that the mass outflow rate ($\sim$ 9 M$_{\odot}$ per year) is about an order of magnitude greater than the predicted rate at which supernovae and stellar winds return mass into the interstellar medium and, therefore, argue that the flow is strongly "mass-loaded" with material in and around the starburst. The estimated outflow velocity of the hot gas is close to the escape velocity from the galaxy, so the fate of the gas is not clear. We suggest that the hard X-ray spectral component is due to the combined emission of X-ray binaries and/or young supernovae remnants associated with the starburst.Comment: 26 pages plus 4 figures, LaTex manuscript, Accepted for publication in the Astrophysical Journa

Very Extended X-ray and H-alpha Emission in M82: Implications for the Superwind Phenomenon

We discuss the properties and implications of a 3.7x0.9 kpc region of spatially-coincident X-ray and H-alpha emission about 11.6 kpc to the north of the galaxy M82 previously discussed by Devine and Bally (1999). The PSPC X-ray spectrum is fit by thermal plasma (kT=0.80+-0.17 keV) absorbed by only the Galactic foreground column density. We evaluate the relationship of the X-ray/H-alpha ridge to the M82 superwind. The main properties of the X-ray emission can all be explained as being due to shock-heating driven as the superwind encounters a massive ionized cloud in the halo of M82. This encounter drives a slow shock into the cloud, which contributes to the excitation of the observed H-alpha emission. At the same time, a fast bow-shock develops in the superwind just upstream of the cloud, and this produces the observed X-ray emission. This interpretation would imply that the superwind has an outflow speed of roughly 800 km/s, consistent with indirect estimates based on its general X-ray properties and the kinematics of the inner kpc-scale region of H-alpha filaments. The gas in the M82 ridge is roughly two orders-of-magnitude hotter than the minimum "escape temperature" at this radius, so this gas will not be retained by M82. (abridged)Comment: 24 pages (latex), 3 figures (2 gif files and one postscript), accepted for publication in Part 1 of The Astrophysical Journa

Immunotherapy for Infarcts: In Vivo Postinfarction Macrophage Modulation Using Intramyocardial Microparticle Delivery of Map4k4 Small Interfering RNA

The myeloid cells infiltrating the heart early after acute myocardial infarction elaborate a secretome that largely orchestrates subsequent ventricular wall repair. Regulating this innate immune response could be a means to improve infarct healing. To pilot this concept, we utilized (beta1,3-d-) glucan-encapsulated small interfering RNA (siRNA)-containing particles (GeRPs), targeting mononuclear phagocytes, delivered to mice as a one-time intramyocardial injection immediately after acute infarction. Findings demonstrated that cardiac macrophages phagocytosed GeRPs in vivo and had little systemic dissemination, thus providing a means to deliver local therapeutics. Acute infarcts were then injected in vivo with phosphate-buffered saline (PBS; vehicle) or GeRPs loaded with siRNA to Map4k4, and excised hearts were examined at 3 and 7 days by quantitative polymerase chain reaction, flow cytometry, and histology. Compared with infarcted PBS-treated hearts, hearts with intrainfarct injections of siRNA-loaded GeRPs exhibited 69-89% reductions in transcripts for Map4k4 (mitogen-activated protein kinase kinase kinase kinase 4), interleukin (IL)-1beta, and tumor necrosis factor alpha at 3 days. Expression of other factors relevant to matrix remodeling-monocyte chemoattractant protein-1 (MCP-1), matrix metalloproteinases, hyaluronan synthases, matricellular proteins, and profibrotic factors transforming growth factor beta (TGF-beta), and connective tissue growth factor (CTGF)-were also decreased. Most effects peaked at 3 days, but, in some instances (Map4k4, IL-1beta, TGF-beta, CTGF, versican, and periostin), suppression persisted to 7 days. Thus, direct intramyocardial GeRP injection could serve as a novel and clinically translatable platform for in vivo RNA delivery to intracardiac macrophages for local and selective immunomodulation of the infarct microenvironment

Development of a Student Self-Reported Instrument to Assess Course Reform

This study examines the development and implementation of a survey-based instrument assessing the effectiveness of a course redesign initiative focused on student centeredness at a large midwestern university in the United States. Given the scope of the reform initiative under investigation in this study, researchers developed an instrument called the Classroom Experience Questionnaire (CEQ), which was administered to students enrolled in redesigned courses. Early findings demonstrate strong construct validity and internal reliability of the CEQ instrument as well as concurrent validity between the CEQ and observation data gathered in concert with self-report data. The authors conclude that in the absence of trained classroom observers, the developed student self-report protocol can serve as a useful tool for measuring the constructivist orientation of pedagogy and student-centered nature of the learning environment in a higher education setting

Chronic viral infection promotes sustained Th1-derived immunoregulatory IL-10 via BLIMP-1

During the course of many chronic viral infections, the antiviral T cell response becomes attenuated through a process that is regulated in part by the host. While elevated expression of the immunosuppressive cytokine IL-10 is involved in the suppression of viral-specific T cell responses, the relevant cellular sources of IL-10, as well as the pathways responsible for IL-10 induction, remain unclear. In this study, we traced IL-10 production over the course of chronic lymphocytic choriomeningitis virus (LCMV) infection in an IL-10 reporter mouse line. Using this model, we demonstrated that virus-specific T cells with reduced inflammatory function, particularly Th1 cells, display elevated and sustained IL-10 expression during chronic LCMV infection. Furthermore, ablation of IL-10 from the T cell compartment partially restored T cell function and reduced viral loads in LCMV-infected animals. We found that viral persistence is needed for sustained IL-10 production by Th1 cells and that the transcription factor BLIMP-1 is required for IL-10 expression by Th1 cells. Restimulation of Th1 cells from LCMV-infected mice promoted BLIMP-1 and subsequent IL-10 expression, suggesting that constant antigen exposure likely induces the BLIMP-1/IL-10 pathway during chronic viral infection. Together, these data indicate that effector T cells self-limit their responsiveness during persistent viral infection via an IL-10-dependent negative feedback loop.This work was supported by an Australian NHMRC Overseas Biomedical Postdoctoral Fellowship (to I.A. Parish); a Yale School of Medicine Brown-Coxe Postdoctoral Fellowship (to I.A. Parish); the Alexander von Humboldt Foundation (SKA2010, to P.A. Lang); a CIHR grant (to P.S. Ohashi); and by the Howard Hughes Medical Institute and NIH grant RO1AI074699 (to S.M. Kaech). P.S. Ohashi holds a Canada Research Chair in Autoimmunity and Tumor immunity

Hubble Space Telescope Observations of Comet 9P/Tempel 1 during the Deep Impact Encounter

We report on the Hubble Space Telescope program to observe periodic comet 9P/Tempel 1 in conjunction with NASA's Deep Impact mission. Our objectives were to study the generation and evolution of the coma resulting from the impact and to obtain wide-band images of the visual outburst generated by the impact. Two observing campaigns utilizing a total of 17 HST orbits were carried out: the first occurred on 2005 June 13-14 and fortuitously recorded the appearance of a new, short-lived fan in the sunward direction on June 14. The principal campaign began two days before impact and was followed by contiguous orbits through impact plus several hours and then snapshots one, seven, and twelve days later. All of the observations were made using the Advanced Camera for Surveys (ACS). For imaging, the ACS High Resolution Channel (HRC) provides a spatial resolution of 36 km (16 km/pixel) at the comet at the time of impact. Baseline images of the comet, made prior to impact, photometrically resolved the comet's nucleus. The derived diameter, 6.1 km, is in excellent agreement with the 6.0 +/- 0.2 km diameter derived from the spacecraft imagers. Following the impact, the HRC images illustrate the temporal and spatial evolution of the ejecta cloud and allow for a determination of its expansion velocity distribution. One day after impact the ejecta cloud had passed out of the field-of-view of the HRC.Comment: 15 pages, 14 postscript figures. Accepted for publication in Icarus special issue on Deep Impac