Analysis of changes in leg volume parameters, and orthostatic tolerance in response to lower body negative pressure during 59 days exposure to zero gravity Skylab 3

The cardiovascular responses of the Apollo crewmen associated with postflight evaluations indicate varying decrements of orthostatic tolerance. The postflight changes indicate a slightly diminished ability to the cardiovascular system to function effectively against gravity following exposure to weightlessness. The objective of the Skylab LBNP experiments (M092) was to provide information about the magnitude and time course of the cardiovascular changes associated with prolonged periods of exposure to weightlessness. This report details the equipment, signal processing and analysis of the leg volume data obtained from the M092 experiment of the Skylab 3 Mission

Determination of cardiac size from chest roentgenograms following Skylab missions

Decreased cardiothoracic transverse diameter ratios following Mercury, Gemini and Apollo space flights have been reported previously. To evaluate further changes in cardiac size, standard posteroanterior chest films in systole and diastole were obtained before flight and within a few hours after recovery on each of the Skylab astronauts. Postflight chest X-rays were visually compared to the preflight roentgenograms for possible changes in pulmonary vasculature, lung parenchyma, bony or soft tissue structures. From these roentgenograms the following measurements were obtained: cardiac and thoracic transverse diameters, cardiothoracic transverse diameter ratio, cardiac area from the product of both diagonal diameters, cardiac silhouette area by planimetry, thoracic cage area and cardiothoracic area ratio. The postflight frontal cardiac silhouette sizes were significantly decreased when compared with the respective preflight values (P0.05 or 0.01). The observed changes are thought to be related to postflight decrease in the intracardiac chamber volume

MoonLITE – Technological feasibility of the penetrator concept

Introduction: While the surface missions to the Moon of the 1960s and 1970s achieved a great deal, scientifically a great deal was also left unresolved. The recent plethora of lunar missions (flown or proposed) reflects resurgence in interest in the Moon, not only in its own right, but also as a record of the formation of the Earth-Moon System and the interplanetary environment at 1 AU. Results from orbiter missions have indicated the possible presense of ice within permanently shaded craters at the lunar poles [1] – a situation that, if confirmed, will have profound impacts on lunar exploration

Use of Recombinant Adenovirus Vectored Consensus IFN-α to Avert Severe Arenavirus Infection

Several arenaviruses can cause viral hemorrhagic fever, a severe disease with case-fatality rates in hospitalized individuals ranging from 15-30%. Because of limited prophylaxis and treatment options, new medical countermeasures are needed for these viruses classified by the National Institutes of Allergy and Infectious Diseases (NIAID) as top priority biodefense Category A pathogens. Recombinant consensus interferon alpha (cIFN-α) is a licensed protein with broad clinical appeal. However, while cIFN-α has great therapeutic value, its utility for biodefense applications is hindered by its short in vivo half-life, mode and frequency of administration, and costly production. To address these limitations, we describe the use of DEF201, a replication-deficient adenovirus vector that drives the expression of cIFN-α, for pre- and post-exposure prophylaxis of acute arenaviral infection modeled in hamsters. Intranasal administration of DEF201 24 h prior to challenge with Pichindé virus (PICV) was highly effective at protecting animals from mortality and preventing viral replication and liver-associated disease. A significant protective effect was still observed with a single dosing of DEF201 given two weeks prior to PICV challenge. DEF201 was also efficacious when administered as a treatment 24 to 48 h post-virus exposure. The protective effect of DEF201 was largely attributed to the expression of cIFN-α, as dosing with a control empty vector adenovirus did not protect hamsters from lethal PICV challenge. Effective countermeasures that are highly stable, easily administered, and elicit long lasting protective immunity are much needed for arena and other viral infections. The DEF201 technology has the potential to address all of these issues and may serve as a broad-spectrum antiviral to enhance host defense against a number of viral pathogens

Tightrope walkers and solidarity sisters: critical workplace educators in the garment industry

Abstract: This article focuses on the complex negotiations of critical workplace educators positioned amongst contradictory agendas and discourses in the workplace. While philosophically aligned with critical pedagogical agendas of transformation and collective action for workplace change, these educators perform an array of pedagogic articulations in everyday practice to secure their continued presence in the workplace. What becomes evident in these seemingly opposing articulations are various strategic political positionings of educators alongside their juggling of demands, attachments and inter-identifications with both learners and managers. The pedagogy that emerges challenges conventional binaries of ‘transformative’ and ‘reproductive’ learning. Dynamics of transformation and liberation as well as reproduction and subjugation appear to be interlinked, along with expanding nets of social relations that blur power hierarchies and spatial boundaries, in a pedagogy that ultimately appears to mobilise hope and agency among workers. The workplace educator works a delicate balance of these dynamics to survive. The argument is based on a case study of a garment factory in Canada in which an adult education programme managed to thrive for 17 years: both workers and educators were interviewed in depth

Assessing changes in vascular permeability in a hamster model of viral hemorrhagic fever

<p>Abstract</p> <p>Background</p> <p>A number of RNA viruses cause viral hemorrhagic fever (VHF), in which proinflammatory mediators released from infected cells induce increased permeability of the endothelial lining of blood vessels, leading to loss of plasma volume, hypotension, multi-organ failure, shock and death. The optimal treatment of VHF should therefore include both the use of antiviral drugs to inhibit viral replication and measures to prevent or correct changes in vascular function. Although rodent models have been used to evaluate treatments for increased vascular permeability (VP) in bacterial sepsis, such studies have not been performed for VHF.</p> <p>Results</p> <p>Here, we use an established model of Pichinde virus infection of hamsters to demonstrate how changes in VP can be detected by intravenous infusion of Evans blue dye (EBD), and compare those measurements to changes in hematocrit, serum albumin concentration and serum levels of proinflammatory mediators. We show that EBD injected into sick animals in the late stage of infection is rapidly sequestered in the viscera, while in healthy animals it remains within the plasma, causing the skin to turn a marked blue color. This test could be used in live animals to detect increased VP and to assess the ability of antiviral drugs and vasoactive compounds to prevent its onset. Finally, we describe a multiplexed assay to measure levels of serum factors during the course of Pichinde arenavirus infection and demonstrate that viremia and subsequent increase in white blood cell counts precede the elaboration of inflammatory mediators, which is followed by increased VP and death.</p> <p>Conclusions</p> <p>This level of model characterization is essential to the evaluation of novel interventions designed to control the effects of virus-induced hypercytokinemia on host vascular function in VHF, which could lead to improved survival.</p

Theoretical Risk of Genetic Reassortment Should Not Impede Development of Live, Attenuated Rift Valley Fever (RVF) Vaccines Commentary on the Draft WHO RVF Target Product Profile

In November 2019, The World Health Organization (WHO) issued a draft set of Target Product Profiles (TPPs) describing optimal and minimally acceptable targets for vaccines against Rift Valley fever (RVF), a Phlebovirus with a three segmented genome, in both humans and ruminants. The TPPs contained rigid requirements to protect against genomic reassortment of live, attenuated vaccines (LAVs) with wild-type RVF virus (RVFV), which place undue constraints on development and regulatory approval of LAVs. We review the current LAVs in use and in development, and conclude that there is no evidence that reassortment between LAVs and wild-type RVFV has occurred during field use, that such a reassortment event if it occurred would have no untoward consequence, and that the TPPs should be revised to provide a more balanced assessment of the benefits versus the theoretical risks of reassortment

MoonLITE programmatic and technological update

MoonLITE is a proposed four penetrator lunar mission. Following a US/UK working group assessment, a science assessment and the first UK impact trials, a full mission-level phase A study has begun. A technological and programmatic update of the mission is given

The Relationship between Phytoplankton Distribution and Water Column Characteristics in North West European Shelf Sea Waters

Phytoplankton underpin the marine food web in shelf seas, with some species having properties that are harmful to human health and coastal aquaculture. Pressures such as climate change and anthropogenic nutrient input are hypothesized to influence phytoplankton community composition and distribution. Yet the primary environmental drivers in shelf seas are poorly understood. To begin to address this in North Western European waters, the phytoplankton community composition was assessed in light of measured physical and chemical drivers during the “Ellett Line” cruise of autumn 2001 across the Scottish Continental shelf and into adjacent open Atlantic waters. Spatial variability existed in both phytoplankton and environmental conditions, with clear differences not only between on and off shelf stations but also between different on shelf locations. Temperature/salinity plots demonstrated different water masses existed in the region. In turn, principal component analysis (PCA), of the measured environmental conditions (temperature, salinity, water density and inorganic nutrient concentrations) clearly discriminated between shelf and oceanic stations on the basis of DIN∶DSi ratio that was correlated with both salinity and temperature. Discrimination between shelf stations was also related to this ratio, but also the concentration of DIN and DSi. The phytoplankton community was diatom dominated, with multidimensional scaling (MDS) demonstrating spatial variability in its composition. Redundancy analysis (RDA) was used to investigate the link between environment and the phytoplankton community. This demonstrated a significant relationship between community composition and water mass as indexed by salinity (whole community), and both salinity and DIN∶DSi (diatoms alone). Diatoms of the Pseudo-nitzschia seriata group occurred at densities potentially harmful to shellfish aquaculture, with the potential for toxicity being elevated by the likelihood of DSi limitation of growth at most stations and depths

Impacts of climate change on harmful algal blooms

High biomass Harmful Algal Blooms (HABs) such as Karenia mikimotoi and shellfish toxin producing HAB species continue to be observed in UK and Republic of Ireland waters. Regional differences continue to be seen in the distribution of HABs in UK and RoI waters with impacts mainly observed in the south and west coast of Ireland and regions in the UK with a strong Atlantic influence, e.g. Regions 1, 3, 4, 6 and 7. There is little monitoring aside from the continuous plankton recorder (CPR) in Region 8. The impacts from HABs in Wales, Northern Ireland and the Isle of Man are generally low. Since the last MCCIP report card was issued, blooms of Karenia mikimotoi have caused problems in Ayrshire, Scotland, and also in the north-west coast of Ireland where concerns about the quantity of dead wild fish washing on shore during an event in Ireland in 2012 resulted in two beaches being closed to the public. No clear trend that can be attributed to climate change can be observed in the incidence of shellfish toxin producing HABs since the last report card was issued. During the last two years the incidence of some shellfish toxins has continued to decrease (e.g. paralytic shellfish poisoning toxins in Scotland). High concentrations of yessotoxins (YTX) and azaspiracids (AZAs) have been recorded for the first time in Scotland. Northern Ireland enforced its first shellfish harvesting closure for high concentrations of domoic acid (the toxin responsible for amnesic shellfish poisoning, ASP) in 2012. A recent survey in Scottish waters (Regions 1, 6 and 7) has revealed the presence of domoic acid in the urine and faeces of harbour seals (Phoca vitulina). The impacts of these toxins on the health of marine mammals are unknown and a more detailed study is currently being undertaken. Many of the future impacts of climate change are unknown. Increasing sea surface temperatures as a result of climate change may increase the potential for blooms of species that are not currently found in UK and RoI waters through range expansion or human mediated introduction. There is evidence that no new HAB species have become established during the last two years. An increase in the duration of stratification of the water column may influence the abundance of HABs in UK and RoI waters. This is particularly relevant in shelf areas and Region 8, an area where offshore high biomass K. mikimotoi blooms have been hypothesized to initiate and impact coastal areas along the west of Ireland and Regions 6, 7 and 1. Conversely, an increase in wind speed and duration may reduce the duration of stratification in the water column. This may result in a decrease of some HAB dinoflagellate species and an increase in HAB diatom species. Little is known about the impacts of ocean acidification or changes in offshore circulation on the incidence of HABs. The role of offshore blooms in seeding coastal blooms (e.g. of K. mikimotoi) remains unknown and the lack of monitoring in Region 8 and on the shelf edge compounds this knowledge gap