Breaking the Pressure Barrier: A History of the Spacesuit Injection Patch

The spacesuit assembly has a fascinating and complicated history dating back to the early 1930s. Much has been written on this history from an assembly perspective and, to a lesser extent, a component perspective. However, little has been written or preserved specifically on smaller, lesser-known aspects of pressure suit design. One example of this is the injection patch - a small 2-in.-diameter disk on the leg of the Apollo suit that facilitated a medical injection when pressurized, and the only known implementation of such a feature on a flight suit. Whereas many people are aware this feature existed, very little is known of its origin, design, and use, and the fact that the Apollo flight suit was not the only instance in which such a feature was implemented. This paper serves to tell the story of this seeming "afterthought" of a feature, as well as the design considerations heeded during the initial development of subsequent suits

The Effect of Mechanical Stimulation on Bone Fracture Healing: Changes in Callus Morphology and Mesenchymal Stem Cell Homing.

This dissertation examines how the timing of an applied strain influences callus morphology during bone fracture repair, and how this load effects the migration of systemically delivered mesenchymal stem cells (MSCs) to the fracture site. Six-month-old, male, Sprague-Dawley rats underwent a 2mm segmental osteotomy in the mid-diaphysis of each femur. A two-piece external fixator with locking plate was fixed to each femur, an osteotomy created with an oscillating saw, and the surrounding tissues closed. Systemic injections of green fluorescent protein (GFP) labeled MSCs were performed via the tail vein on the first loading day. Axial mechanical stimulation occurred for five consecutive days at 0, 3, 10, or 24 days post-operative at a magnitude of ±8% strain and a rate of 0.313 Hz for 510 cycles. Rats were euthanized 10, 24, or 48 days post-op. Through a micro-CT analysis, mineralization was found to be increased in animals that underwent the applied displacement at day ten when compared to the other groups. Histology showed that by day 48, these animals had almost no cartilage remaining, indicating advanced remodeling in comparison to other groups. The animals stimulated at day three showed the opposite trends, with less mineralization and larger, less remodeled calluses by day 48. Planar gamma imaging of 111indium tagged MSCs showed that injected cells migrate from the lungs and liver, and a certain percentage of them are available to the limbs. Axial displacement created some difference in MSC migration to the limbs, but these disappeared by day three. As analyzed by immunohistochemistry, there were significant numbers of MSCs in the marrow spaces by day 48, and a qualitative analysis suggests that stimulation may encourage the cell to preferentially migrate. A polymerase chain reaction (PCR) array examined the genetic expression of 80 genes in the fracture gap tissue implicated in migration of MSC migration. It showed that the expression of many different genetic factors is influenced by mechanical stimulation. This effect also appears to not just be localized, but can be seen systemically as well. Overall, the timing of displacement had a significant effect on fracture healing, both locally and systemically.Ph.D.Mechanical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/61660/1/asweaver_1.pd

Evaluation of Hand-to-Hand Bioelectrical Impedance Analysis for Estimating Percent Body Fat in Young Adults

Purposes were to (a) to examine the validity and precision of a hand-to-hand bioelectrical impedance analyzer (HBIA) and (b) to determine the effect of an acute sub-maximal aerobic exercise bout on HBIA percent body fat (%BF) measures. Forty-one young adults (21 women; 20 men) visited the laboratory for body composition assessment on two separate occasions. During the control session, %BF was assessed by HBIA twice, before and immediately after 30 min of rest, and once by air-displacement plethysmography (ADP), using the BOD POD, which was considered the criterion method for comparison. During the exercise session, HBIA %BF measurements were determined prior-to and immediately after 30 minutes of moderate-intensity treadmill exercise. HBIA significantly underestimated %BF in the total sample (mean difference (MD) = 1.4 ± 4.3%) and, when examined by gender, in the women (MD = 2.4 ± 4.1%). The standard errors of estimate (range 4.1-4.3%) also exceeded the recommended range for accuracy (\u3c3.5%). Following exercise, there was minimal, but statistically significant reduction in HBIA-measured %BF pre- to post-exercise for the total sample (19.6 ± 6.0 vs. 19.3 ± 6.0%; p = 0.011). HBIA underestimated %BF when compared to ADP and the individual prediction error exceeded current recommendations when assessing young adults. In addition, performing sub-maximal aerobic exercise prior to the assessment decreased the %BF estimate. When one factors the exercise-induced alterations with the currently observed tendency for HBIA to underestimate %BF, it is apparent that exercise may further reduce the accuracy of this method

Assessing the Likelihood of Rare Medical Events in Astronauts

Despite over half a century of manned space flight, the space flight community is only now coming to fully assess the short and long term medical dangers of exposure to reduced gravity environments. Further, as new manned spacecraft are designed and with the advent of commercial flight capabilities to the general public, a full understanding of medical risk becomes even more critical for maintaining and understanding mission safety and crew health. To address these critical issues, the National Aeronautics and Space Administration (NASA) Human Research Program (HRP) has begun to address the medical hazards with a formalized risk management approach by effectively identifying and attempting to mitigate acute and chronic medical risks to manned space flight. This paper describes NASA Glenn Research Center?s (GRC) efforts to develop a systematic methodology to assess the likelihood of in-flight medical conditions. Using a probabilistic approach, medical risks are assessed using well established and accepted biomedical and human performance models in combination with fundamentally observed data that defines the astronauts? physical conditions, environment and activity levels. Two different examples of space flight risk are used to show the versatility of our approach and how it successfully integrates disparate information to provide HRP decision makers with a valuable source of information which is otherwise lacking

Ultrasound-determined diameter measurements are more accurate than axial computed tomography after endovascular aortic aneurysm repair

ObjectiveThis study evaluated the correlation of ultrasound (US)-derived aortic aneurysm diameter measurements with centerline, three-dimensional (3-D) reconstruction computed tomography (CT) measurements after endovascular aortic aneurysm repair (EVAR).MethodsConcurrent CT and US examinations from 82 patients undergoing post-EVAR surveillance were reviewed. The aortic aneurysm diameter was defined as the major axis on the centerline images of 3-D CT reconstruction. This was compared with US-derived minor and major axis measurements, as well as with the minor axis measurement on the conventional axial CT images. Correlation was evaluated with linear regression analyses. Agreement between different imaging modalities and measurements was assessed with Bland-Altman plots.ResultsThe correlation coefficients from linear regression analyses were 0.92 between CT centerline major and US minor measurements, 0.94 between CT centerline major and US major measurements, and 0.93 between CT minor and centerline major measurements. Bland-Altman plots showed a mean difference of 0.11 mm between US major and CT centerline measurements compared with 5.38 mm between US minor and CT centerline measurements, and 4.25 mm between axial CT minor and centerline measurements. This suggested that, compared with axial CT and US minor axis measurements, US major axis measurements were in better agreement with CT centerline measurements. Variability between major and minor US and CT centerline diameter measurements was high (standard deviation of difference, 4.27-4.84 mm). However, high variability was also observed between axial CT measurements and centerline CT measurements (standard deviation of difference, 4.36 mm).ConclusionsThe major axis aneurysm diameter measurement obtained by US imaging for surveillance after EVAR correlates well and is in better agreement with centerline 3-D CT reconstruction diameters than axial CT

Estimated Probabililty of Chest Injury During an International Space Station Mission

The Integrated Medical Model (IMM) is a decision support tool that is useful to spaceflight mission planners and medical system designers when assessing risks and optimizing medical systems. The IMM project maintains a database of medical conditions that could occur during a spaceflight. The IMM project is in the process of assigning an incidence rate, the associated functional impairment, and a best and a worst case end state for each condition. The purpose of this work was to develop the IMM Chest Injury Module (CIM). The CIM calculates the incidence rate of chest injury per person-year of spaceflight on the International Space Station (ISS). The CIM was built so that the probability of chest injury during one year on ISS could be predicted. These results will be incorporated into the IMM Chest Injury Clinical Finding Form and used within the parent IMM model

Comparative Analysis of the Structure and Function of AAA+ Motors ClpA, ClpB, and Hsp104: Common Threads and Disparate Functions

Cellular proteostasis involves not only the expression of proteins in response to environmental needs, but also the timely repair or removal of damaged or unneeded proteins. AAA+ motor proteins are critically involved in these pathways. Here, we review the structure and function of AAA+ proteins ClpA, ClpB, and Hsp104. ClpB and Hsp104 rescue damaged proteins from toxic aggregates and do not partner with any protease. ClpA functions as the regulatory component of the ATP dependent protease complex ClpAP, and also remodels inactive RepA dimers into active monomers in the absence of the protease. Because ClpA functions both with and without a proteolytic component, it is an ideal system for developing strategies that address one of the major challenges in the study of protein remodeling machines: how do we observe a reaction in which the substrate protein does not undergo covalent modification? Here, we review experimental designs developed for the examination of polypeptide translocation catalyzed by the AAA+ motors in the absence of proteolytic degradation. We propose that transient state kinetic methods are essential for the examination of elementary kinetic mechanisms of these motor proteins. Furthermore, rigorous kinetic analysis must also account for the thermodynamic properties of these complicated systems that reside in a dynamic equilibrium of oligomeric states, including the biologically active hexamer

Moving the Needle on Poverty

Contents: Preface - Pathways to Poverty Reduction through Community-Campus Partnerships Chapter One: Creating Strategic Partnerships to Influence Policy (Liz Weaver) Chapter Two: Models of Community-Campus Engagement in the Poverty Reduction Hub of CFICE (Karen Schwartz) Chapter Three: University and Community Collaboration: Achieving Social Change (Erin Bigney, Tracey Chiasson, Melanie Hientz, Robert MacKinnon and Cathy Wright) Chapter Four: On a Path of True Reconciliation: Investing in a Poverty-free Saskatoon (Colleen Christopherson-Côté, Lisa Erickson, Isobel M. Findlay and Vanessa Charles) Chapter Five: Using Campus Community Engagement to Build Capacity for Poverty Reduction (Amanda Lefrancois) Chapter Six: Shifting Societal Attitudes Regarding Poverty: Reflections on a Successful Community-University Partnership ( Mary MacKeigan, Jessica Wiese, Terry Mitchell, Colleen Loomis and Alexa Stovold) Chapter Seven: Models of Collaboration: Does Community Engagement with University Colleges Have an Impact on Poverty Reduction? (Polly Leonard and Karen Schwartz) Chapter Eight: A Peephole into the Student Experience: Student Research Assistants on their Experiences in the Poverty Reduction Hub (Aaron Kozak, Zhaocheng Zeng and Natasha Pei) Chapter Nine: Poverty Reduction Hub Evaluation (Aaron Kozak, Karen Schwartz, Amanda Lefrancois and Liz Weaver) Chapter Ten: Conclusion (Magdalene Goemans)</small

The Hierarchical Taxonomy of Psychopathology (HiTOP) Is Not an Improvement Over the DSM

DeYoung and colleagues did not sufficiently address three fundamental flaws with HiTOP. First, HiTOP was created using a simple structure factor analytic approach, which does not adequately represent the dimensional space of the symptoms of psychopathology. Consequently, HiTOP is not the empirical structure of psychopathology. Second, factor analysis and dimensional ratings do not fix the problems inherent to descriptive (folk) classification; self-reported symptoms are still the basis upon which clinical judgments about people are made. Finally, HiTOP is not ready to use in real-world clinical settings. There is currently no empirical evidence demonstrating that clinicians who use HiTOP have better clinical outcomes than those who use the DSM. In sum, HiTOP is a factor analytic variation of the DSM that does not get us closer to a more valid and useful taxonomy

Statewide Dissemination and Implementation of Physical Activity Standards in Afterschool Programs: Two-Year Results

Background: In 2015, YMCA afterschool programs (ASPs) across South Carolina, USA pledged to achieve the YMCA physical activity standard calling for all children to accumulate 30 min of moderate-to-vigorous physical activity (MVPA) while attending their ASPs. This study presents the final two-year outcomes from the dissemination and implementation efforts associated with achieving this MVPA standard. Methods: Twenty ASPs were sampled from all South Carolina YMCA-operated ASPs (N = 97) and visited at baseline (2015) and first (2016) and second year (2017) follow-up. All ASPs were provided training to increase MVPA during the program by extending the scheduled time for activity opportunities and modifying commonly played games to increase MVPA. The RE-AIM framework was used to evaluate the statewide intervention. Accelerometer-derived MVPA was the primary outcome. Intent-to-treat (ITT) models were conducted summer 2017. Programs were also classified, based on changes in MVPA from 2015 to 2016 and 2016–2017, into one of three categories: gain, maintain, or lost. Implementation, within the three groups, was evaluated via direct observation and document review. Results: Adoption during the first year was 45% of staff attending training, with this increasing to 67% of staff during the second year. ITT models indicated no increase in the odds of accumulating 30 min of MVPA after the first year for either boys (odds ratio [OR] 1.06, 95CI 0.86–1.31) or girls (OR 1.14, 95CI 0.87–1.50), whereas an increase in the odds was observed during the second year for boys (OR 1.31, 95CI 1.04–1.64) and girls (OR 1.50 95CI 1.01–1.80). Programs that lost MVPA (avg. − 5 to − 7.5 min/d MVPA) elected to modify their program in a greater number of non-supportive ways (e.g., reduce time for activity opportunities, less time spent outdoors), whereas ASPs that gained MVPA (avg. + 5.5 to + 10.1 min MVPA) elected to modify their program in more supportive ways. Conclusions: The statewide study demonstrated minimal improvements in overall MVPA. However, child MVPA was dramatically influenced by ASPs who elected to modify their daily program in more supportive than non-supportive ways, with no one program modifying their program consistently across the multi-year initiative. These findings have important implications for organizations seeking to achieve the MVPA standard