Mechanical Counter-Pressure EVA Suits: NASA Outlook and Development Strategy

Since the 1950s, mechanical counter-pressure (MCP) has been investigated as a possible alternative architecture to traditional extra-vehicular activity (EVA) suits. While traditional gas-pressurized EVA suits provide physiological protection against the ambient vacuum environment by means of pressurized oxygen to at least 3.1 psid, MCP provides protection by direct application of pressure on the skin by a fabric. In reviewing the concept, MCP offers distinct potential advantages to traditional EVA suits: lower mass, reduced consumables, increased mobility, increased comfort, less complexity, and improved failure modes. In addition, as basic feasibility was established in the 1960s with the successful testing of the Space Activity Suit, MCP seems poised to inevitably supplant traditional EVA architectures with a modest degree of concentrated development. However, as they say, "The devil is in the details". This paper serves as a comprehensive summary of the technical work that has been completed related to MCP from 1960 to 2019, the technical gaps that need to be closed to facilitate a flight-capable design, and outlines an overall development strategy that NASA feels would best address these gaps moving forward

NASA Advanced Space Suit Pressure Garment System Status and Development Priorities 2019

This paper discusses the current focus of NASA's Advanced Space Suit Pressure Garment Technology Development team's efforts, the status of that work, and a summary of longer term technology development priorities and activities. The Exploration Extra-vehicular Activity Unit (xEMU) project's International Space Station Demonstration Suit (xEMU Demo) project continues to be the team's primary customer and effort. In 2018 the team was engaged in addressing hardware design changes identified in the Z-2 pressure garment prototype Neutral Buoyancy Laboratory (NBL) test results. These changes will be discussed. Additionally components whose first iterations were produced in 2018 will be discussed. A full pressure garment prototype, termed Z-2.5, was assembled that is composed of updated and first prototype iteration hardware. Z-2.5 NBL testing, performed from October 2018 through April 2019 will inform final design iterations in preparation for the xEMU Demo preliminary design review planned to occur in the third quarter of government fiscal year 2019. A primary objective of the Z-2.5 NBL testing is to validate changes made to the hard upper torso geometry, which depart from the planetary walking suit upper torso geometry that has been used over the last 30 years. The team continues to work technology development, with GFY2018 work being used to supplement and feed the gaps left by the scope defined for the xEMU Demo. Specifically, a Phase IIx Small Business Innovative Research Grant to mature durable bearings that are compatible with a dust environment and a grant funded by the Science Technology Mission Directorate, Lightweight and Robust Exploration Space Suit (LARESS) project, to mature planetary impact requirements and hardware will be described. Finally, a brief review of longer-term pressure garment challenges and technology gaps will be presented to provide an understanding of the advanced pressure garment team's technology investment priorities and needs

Growing Minds: The Relationship Between Parental Attitude about Nature and the Development of Fine and Gross Motor Skills in Children

Adults associate their childhood with playing outdoors, often in natural settings. This type of free play is valuable to child development. Children tend to use outdoor play areas in physically active ways, and time spent outdoors relates positively to increased physical activity in children. However, children today are spending an increasing amount of time indoors rather than outdoors. Recent research has shown that the amount of time children spend in outdoor play is directly related to parental concerns about their children's exposure to outdoor hazards. The purpose of this project was to investigate the relationship between parental attitude toward nature and the development of fine and gross motor skills in young children. The sample for this study was drawn from parents of children ages 3 to 5 years old enrolled at one of two University Child Development Centers. The assessment tool used was composed of sections that ask parents about their attitudes toward nature, about their young children spending time outdoors, how much time their children actually spend in outdoor and indoor activities, and standard demographic questions. The childcare centers independently assessed d correlations and ANOVA. Results from this study indicated that parents had positive views toward nature and towards their child's recreation. Children who participated in certain indoor activities tended to score higher in the area of fine motor skills. However, children who spent more time indoors in free play had lower gross motor skill scores. Parents who scored better on the Parental Attitude toward Their Child's Outdoor Recreation scale reported that their child spent more time in outdoor free play and outdoor organized sports and activities. Parents preferred outdoor play spaces when compared to indoor play spaces and specifically those outdoor spaces that were constructed with more nearby natural components

The "Space Activity Suit" - A Historical Perspective and A Primer on the Physiology of Mechanical Counter-Pressure

Since the 1950s, mechanical counter-pressure (MCP) has been investigated as a possible alternative design concept to traditional extra-vehicular activity (EVA) space suits. While traditional gas-pressurized EVA suits provide physiological protection against the ambient vacuum by means of pressurized oxygen to at least 3.1 pounds per square inch absolute (160 millimeters of mercury), MCP provides protection by direct application of pressure on the skin by a fabric. In reviewing the concept, MCP offers distinct potential advantages to traditional EVA suits: lower mass, reduced consumables, increased mobility, increased comfort, less complexity, and improved failure modes. In the mid 1960s to early 1970s, Dr. Paul Webb of Webb Associates developed and tested such a suit under funding from NASA Langley Research Center. This "Space Activity Suit" (SAS) was improved many times while testing in the laboratory and an altitude chamber to as low as 0.3 pounds per square inch absolute (15 millimeters of mercury). This testing, and the reports by Webb documenting it, are often presented as evidence of the feasibility of MCP. In addition, the SAS reports contain a wealth of information regarding the physiological requirements to make MCP work at the time, which is still accurate today. This paper serves to document the Space Activity Suit effort and analyze it in today's context

A Two-Chain Path Integral Model Of Positronium

We have used a path integral Monte Carlo technique to simulate positronium (Ps) in a cavity. The primitive propagator is used, with a pair of interacting chains representing the positron and electron. We calculate the energy and radial distribution function for Ps enclosed in a hard, spherical cavity, and the polarizability of the model Ps in the presence of an electrostatic field. We find that the positron distribution near the hard wall differs significantly from that for a single particle in a hard cavity. This leads to systematic deviations from predictions of free-volume models which treat Ps as an effective, single particle. A virial-type estimator is used to calculate the kinetic energy of the particle in the presence of hard walls. This estimator is found to be superior to a kinetic-type estimator given the interaction potentials, cavity sizes, and chain lengths considered in the current study. (C) 2000 American Institute of Physics. [S0021-9606(00)50447-4]

Use of Gardening Programs as an Intervention to Increase Children’s Ability to Delay Gratification

The purpose of this study was to examine the ability of preschool gardening programs to help children develop their ability to delay gratification. Children today face many opportunities for instant gratification, although the ability to delay gratification in early childhood has been linked to numerous benefits later in life. Opportunities to train children in the ability to delay gratification present educational challenges, in that it competes with other academic training needs, and it can be difficult to find programs that are interesting to young children. The population for this study was preschool children ranging in age from 2 to 6 years, with treatment and control groups drawn from different schools. Participants were tested individually and timed to determine their ability to delay gratification, with promises of larger rewards if the child could wait for 15 minutes. The results of this study did not identify a significant change in all children’s ability to delay gratification after a gardening program. However, analyses showed that females appear to have responded more positively to the gardening treatment in their ability to delay gratification, whereas males in the control group benefited more from traditional school lessons

NASA's Advanced Extra-Vehicular Activity Space Suit Pressure Garment 2018 Status and Development Plan

This paper presents both near-term and long-term NASA Advanced Extra-vehicular Activity (EVA) Pressure Garment development efforts. The near-term plan discusses the development of pressure garment components for the first design iteration of the International Space Station exploration space suit demonstration configuration, termed the xEMU Demo. The xEMU Demo effort is targeting a 2023-2025 flight demonstration timeframe. The Fiscal Year 2018 (FY18) tasks focus on either the initiation or maturation of component design, depending on the state of development of the components, and the assembly of a suit configuration, termed Z-2.5, that will be used to evaluate changes to the upper torso geometry in a Neutral Buoyancy Laboratory (NBL) test series. The geometry changes, which are being driven by the need to reduce the front-to-back dimension of the advanced extravehicular mobility unit, diverge from a proven shape, such as that of the Mark III Space Suit Technology Demonstrator. The 2018 efforts culminate in the Z-2.5 NBL test. The lessons learned from the Z-2.5 NBL test will inform the xEMU Demo design as the effort moves toward design verification testing and preliminary and critical design reviews. The long-term development plan looks to surface exploration and operations. Technology and knowledge gaps exist between the xEMU Demo configuration; a lunar surface capability, xEMU; and Mars surface suit, mEMU. The development plan takes into account both the priority and the anticipated development duration for each particular technology. The long-term development plan will be updated as risks are mitigated and gaps are closed, but its overarching structure will remain intact

Calmodulin acts as a state-dependent switch to control a cardiac potassium channel opening

Calmodulin (CaM) and phosphatidylinositol 4,5-bisphosphate (PI

Editorial: Translational insights into mechanisms and therapy of organ dysfunction in sepsis and trauma

Multiple organ dysfunction or even failure after sepsis or trauma is due to a dysregulated host response. Currently, besides (surgical) source control (e.g., control of bleeding or drainage of abscesses) and administration of antimicrobial drugs, therapeutic approaches are limited to supportive care. Advances in our understanding of the key pathophysiological pathways involved in the excessive inflammation triggered by trauma, sepsis and/or ischemia-reperfusion have had limited impact. The 28 article in this Research Topic focus on the molecular mechanisms behind (hyper) inflammation after sepsis or trauma, with special emphasis on preclinical and translational studies that target potential organ-protective and/or -resuscitative therapeutic strategies. Most studies report rodent models of trauma and elective surgery (three articles), non-microbial hyper-inflammation induced with endotoxin exposure (LPS; seven articles) and chemical pancreatitis (one article), and cecal ligation and puncture-induced sepsis (six articles). Additional papers summarize investigations of human material (six articles) or fully-resuscitated large animal models (two articles). These article are complimented by four reviews and a commentary

No excess of mitochondrial DNA deletions within muscle in progressive multiple sclerosis

BACKGROUND: Mitochondrial dysfunction is an established feature of multiple sclerosis (MS). We recently described high levels of mitochondrial DNA (mtDNA) deletions within respiratory enzyme-deficient (lacking mitochondrial respiratory chain complex IV with intact complex II) neurons and choroid plexus epithelial cells in progressive MS. OBJECTIVES: The objective of this paper is to determine whether respiratory enzyme deficiency and mtDNA deletions in MS were in excess of age-related changes within muscle, which, like neurons, are post-mitotic cells that frequently harbour mtDNA deletions with ageing and in disease. METHODS: In progressive MS cases (n=17), known to harbour an excess of mtDNA deletions in the central nervous system (CNS), and controls (n=15), we studied muscle (paraspinal) and explored mitochondria in single fibres. Histochemistry, immunohistochemistry, laser microdissection, real-time polymerase chain reaction (PCR), long-range PCR and sequencing were used to resolve the single muscle fibres. RESULTS: The percentage of respiratory enzyme-deficient muscle fibres, mtDNA deletion level and percentage of muscle fibres harbouring high levels of mtDNA deletions were not significantly different in MS compared with controls. CONCLUSION: Our findings do not provide support to the existence of a diffuse mitochondrial abnormality involving multiple systems in MS. Understanding the cause(s) of the CNS mitochondrial dysfunction in progressive MS remains a research priority