Technical assessment of Mir-1 life support hardware for the international space station

NASA has been progressively learning the design and performance of the Russian life support systems utilized in their Mir space station. In 1992, a plan was implemented to assess the benefits of the Mir-1 life support systems to the Freedom program. Three primary tasks focused on: evaluating the operational Mir-1 support technologies and understanding if specific Russian systems could be directly utilized on the American space station and if Russian technology design information could prove useful in improving the current design of the planned American life support equipment; evaluating the ongoing Russian life support technology development activities to determine areas of potential long-term application to the U.S. space station; and utilizing the expertise of their space station life support systems to evaluate the benefits to the current U.S. space station program which included the integration of the Russian Mir-1 designs with the U.S. designs to support a crew of six

Low-Temperature Polymorphic Phase Transition in a Crystalline Tripeptide L-Ala-L-Pro-Gly·H2O Revealed by Adiabatic Calorimetry

We demonstrate application of precise adiabatic vacuum calorimetry to observation of phase transition in the tripeptide l-alanyl-l-prolyl-glycine monohydrate (APG) from 6 to 320 K and report the standard thermodynamic properties of the tripeptide in the entire range. Thus, the heat capacity of APG was measured by adiabatic vacuum calorimetry in the above temperature range. The tripeptide exhibits a reversible first-order solid-to-solid phase transition characterized by strong thermal hysteresis. We report the standard thermodynamic characteristics of this transition and show that differential scanning calorimetry can reliably characterize the observed phase transition with <5 mg of the sample. Additionally, the standard entropy of formation from the elemental substances and the standard entropy of hypothetical reaction of synthesis from the amino acids at 298.15 K were calculated for the studied tripeptide.National Institute of Biomedical Imaging and Bioengineering (U.S.) (EB-003151)National Institute of Biomedical Imaging and Bioengineering (U.S.) (EB-001960)National Institute of Biomedical Imaging and Bioengineering (U.S.) (EB-002026

Advancing the understanding of treponemal disease in the past and present

Syphilis was perceived to be a new disease in Europe in the late 15th century, igniting a debate about its origin that continues today in anthropological, historical, and medical circles. We move beyond this age-old debate using an interdisciplinary approach that tackles broader questions to advance the understanding of treponemal infection (syphilis, yaws, bejel, and pinta). How did the causative organism(s) and humans co-evolve? How did the related diseases caused by Treponema pallidum emerge in different parts of the world and affect people across both time and space? How are T. pallidum subspecies related to the treponeme causing pinta? The current state of scholarship in specific areas is reviewed with recommendations made to stimulate future work. Understanding treponemal biology, genetic relationships, epidemiology, and clinical manifestations is crucial for vaccine development today and for investigating the distribution of infection in both modern and past populations. Paleopathologists must improve diagnostic criteria and use a standard approach for recording skeletal lesions on archaeological human remains. Adequate contextualization of cultural and environmental conditions is necessary, including site dating and justification for any corrections made for marine or freshwater reservoir effects. Biogeochemical analyses may assess aquatic contributions to diet, physiological changes arising from treponemal disease and its treatments (e.g., mercury), or residential mobility of those affected. Shifting the focus from point of origin to investigating who is affected (e.g., by age/sex or socioeconomic status) and disease distribution (e.g., coastal/ inland, rural/urban) will advance our understanding of the treponemal disease and its impact on people through time

SIP metagenomics identifies uncultivated Methylophilaceae as dimethylsulphide degrading bacteria in soil and lake sediment.

Dimethylsulphide (DMS) has an important role in the global sulphur cycle and atmospheric chemistry. Microorganisms using DMS as sole carbon, sulphur or energy source, contribute to the cycling of DMS in a wide variety of ecosystems. The diversity of microbial populations degrading DMS in terrestrial environments is poorly understood. Based on cultivation studies, a wide range of bacteria isolated from terrestrial ecosystems were shown to be able to degrade DMS, yet it remains unknown whether any of these have important roles in situ. In this study, we identified bacteria using DMS as a carbon and energy source in terrestrial environments, an agricultural soil and a lake sediment, by DNA stable isotope probing (SIP). Microbial communities involved in DMS degradation were analysed by denaturing gradient gel electrophoresis, high-throughput sequencing of SIP gradient fractions and metagenomic sequencing of phi29-amplified community DNA. Labelling patterns of time course SIP experiments identified members of the Methylophilaceae family, not previously implicated in DMS degradation, as dominant DMS-degrading populations in soil and lake sediment. Thiobacillus spp. were also detected in (13)C-DNA from SIP incubations. Metagenomic sequencing also suggested involvement of Methylophilaceae in DMS degradation and further indicated shifts in the functional profile of the DMS-assimilating communities in line with methylotrophy and oxidation of inorganic sulphur compounds. Overall, these data suggest that unlike in the marine environment where gammaproteobacterial populations were identified by SIP as DMS degraders, betaproteobacterial Methylophilaceae may have a key role in DMS cycling in terrestrial environments.HS was supported by a UK Natural Environment Research Council Advanced Fellowship NE/E013333/1), ÖE by a postgraduate scholarship from the University of Warwick and an Early Career Fellowship from the Institute of Advanced Study, University of Warwick, UK, respectively. Lawrence Davies is acknowledged for help with QIIME

Age-Dependent TLR3 Expression of the Intestinal Epithelium Contributes to Rotavirus Susceptibility

Rotavirus is a major cause of diarrhea worldwide and exhibits a pronounced small intestinal epithelial cell (IEC) tropism. Both human infants and neonatal mice are highly susceptible, whereas adult individuals remain asymptomatic and shed only low numbers of viral particles. Here we investigated age-dependent mechanisms of the intestinal epithelial innate immune response to rotavirus infection in an oral mouse infection model. Expression of the innate immune receptor for viral dsRNA, Toll-like receptor (Tlr) 3 was low in the epithelium of suckling mice but strongly increased during the postnatal period inversely correlating with rotavirus susceptibility, viral shedding and histological damage. Adult mice deficient in Tlr3 (Tlr3−/−) or the adaptor molecule Trif (TrifLps2/Lps2) exerted significantly higher viral shedding and decreased epithelial expression of proinflammatory and antiviral genes as compared to wild-type animals. In contrast, neonatal mice deficient in Tlr3 or Trif did not display impaired cell stimulation or enhanced rotavirus susceptibility. Using chimeric mice, a major contribution of the non-hematopoietic cell compartment in the Trif-mediated antiviral host response was detected in adult animals. Finally, a significant age-dependent increase of TLR3 expression was also detected in human small intestinal biopsies. Thus, upregulation of epithelial TLR3 expression during infancy might contribute to the age-dependent susceptibility to rotavirus infection