Explore the vast range of titles available.

Finding sustainable approaches to achieve independence from terrestrial resources is of pivotal importance for the future of space exploration. This is relevant not only to establish viable space exploration beyond low Earth–orbit, but also for ethical considerations associated with the generation of space waste and the preservation of extra-terrestrial environments. Here we propose and highlight a series of microbial biotechnologies uniquely suited to establish sustainable processes for in situ resource utilization and loop-closure. Microbial biotechnologies research and development for space sustainability will be translatable to Earth applications, tackling terrestrial environmental issues, thereby supporting the United Nations Sustainable Development Goals. Establishing sustainable approaches for human space exploration is key to achieve independency from terrestrial resources, as well as for ethical considerations. Here the authors highlight microbial biotechnologies that will support sustainable processes for space-based in situ resource utilization and loop-closure, and may be translatable to Earth applications.

The 104 kb genome of cold-active bacteriophage 9A, which replicates in the marine psychrophilic gamma-proteobacterium Colwellia psychrerythraea strain 34H (between −12 and 8 °C), was sequenced and analyzed to investigate elements of molecular adaptation to low temperature and phage–host interactions in the cold. Most characterized ORFs indicated closest similarity to gamma-proteobacteria and their phages, though no single module provided definitive phylogenetic grouping. A subset of primary structural features linked to psychrophily suggested that the majority of annotated phage proteins were not psychrophilic; those that were, primarily serve phage-specific functions and may also contribute to 9A’s restricted temperature range for replication as compared to host. Comparative analyses suggest ribonucleotide reductase genes were acquired laterally from host. Neither restriction modification nor the CRISPR-Cas system appeared to be the predominant phage defense mechanism of Cp 34H or other cold-adapted bacteria; we hypothesize that psychrophilic hosts rely more on the use of extracellular polymeric material to block cell surface receptors recognized by phages. The relative dearth of evidence for genome-specific defenses, genetic transfer events or auxiliary metabolic genes suggest that the 9A- Cp 34H system may be less tightly coupled than are other genomically characterized marine phage–host systems, with possible implications for phage specificity under different environmental conditions.

As a field, astrobiology spans a range of disciplines, intertwining the tools and foundation that each can bring to a common table of inquiry: Where did we come from? Are we alone? Grand in aspiration, the experimental work behind these questions is of an exacting nature less prone to superlatives, but essential to constraining the likelihood of life’s origin, evolution and detectability on scales spanning galactic to the molecules on which life depends. The work described in this thesis focuses on an extreme environment and the microbial ecology therein. Microbes that inhabit such environments are of fundamental interest to astrobiologists, as they open windows to observe deviations on biological processes such as might be found under conditions disparate from what we have traditionally thought of as hospitable conditions for life. These conditions are informative to considering life on other planetary bodies, or on early Earth, when the chemistry of the oceans and atmosphere were substantially different than they are today. The environments on which this work focuses are two polar hypersaline springs in the Canadian High Arctic, considered extreme by their low temperature, high salinity and low oxygen. Within those springs, this work focuses on two processes: 1) microbial mortality at the hands of tiny and ubiquitous predators: viruses; and 2) biosignatures of microbial metabolism that can endure in the rock record: isotopes of sulfur.The abundance of viruses from Arctic hypersaline spring water and sediment environments was investigated and from those findings the first estimates of contact rates between viruses and bacteria in sediments were made. The extremely oligotrophic nature of these springs maintains some of the lowest virus-bacteria ratios and contact rates observed in natural environments to date, indicating that viruses do not play a major lytic role in these springs and that alternative viral replication strategies maintain the free virion population. Comparison of these results to reports from marine sediments identifies a viral biogeographic divide in deep-sea sediments that separates shallower bacterial communities controlled by lytic viruses from deeper ones that are not. Paper 1 is titled Low viral predation pressure in cold hypersaline springs of Axel Heiberg Island.Complementary viral dynamics experiments were performed in cold, oligotropic sediments of polar hypersaline spring sediments in the Canadian High Arctic. This work specifically addresses 1) the trophic hypothesis of viral influence on microbial growth: that there is a direct relationship between trophic conditions and the predatory influence exerted by viruses on their microbial hosts, and 2) the relationship between oligotrophy and lysogenic replication: that in oligotrophic environments, viruses capable of this replication strategy are more common. By nature of their low temperature, high salinity and low carbon availability, the springs investigated in this study represent an experimentally accessible, low energy environmental outlier in which to test these hypotheses. These sediments maintain extremely low rates of microbial growth and viral production and a substantial fraction of viruses are extremely resistant to decay. These viruses do contribute to microbial mortality, but are not the primary cause of such. A substantial fraction of microbes in these sediments appear to be lysogens, harboring inducible provirus, yet temperate viruses do not seem to account for a large fraction of the in situ population of virions. These findings support the trophic hypothesis, but offer limited support for an increasing frequency of lysogens in oligotrophic environments. These findings extend the range of geochemical conditions under which viral dynamics have been explored and suggest that viruses are able to maintain a role in microbial mortality even in extremely low biomass environments, potentially by means of resisting decay (providing a longer period for them to contact a host). Paper 2 is titled Sluggish viral dynamics in Arctic hypersaline spring sediments.Finally the preserved signals of biological isotopic fractionation of sulfur in one of the two springs was described, as were the accompanying sulfate reducing microorganisms that inhabit its cold, oligotropic sediments. This work specifically addresses the influence that environmental chemistry and genomic diversity have on the fractionation of sulfur isotopes across a small spatial scale with variations in redox, pH, temperature, dissolved oxygen and dissolved sulfide, as well as microbial taxonomic composition and diversity in the final gene in the sulfate reduction pathway. These sediments show little variation in sulfur fractionation, despite differences in several of the characters known to contribute to the extent of fractionation by cultured sulfate reducing isolates. To address the discrepancy between measured and modeled cell-specific sulfate reduction rates (csSRR) and isotopic fractionation; environmental data from the spring was incorporated into a previously reported thermodynamic-based model. The model indicated the most likely cause of deviation from predicted fractionation values was a greater than measured csSRR, suggesting heterogeneous activity among that group. Employing the same model to address the unexpected lack of correlation between dsrB alpha diversity metrics and relatively constant sulfur isotope fractionation between stations, kinetic parameters associated with the apr gene in the sulfate reduction pathway were found to have greater influence on expressed fractionation factor than the dsr gene. Paper 3 is titled Diversity-signal disconnect between dsrB sequencing and sulfur isotope fractionation signals.

The extent of fractionation of sulfur isotopes by sulfate reducing microbes is dictated by genomic and environmental factors. A greater understanding of species-specific fractionations may better inform interpretation of sulfur isotopes preserved in the rock record. To examine whether gene diversity influences net isotopic fractionation in situ, we assessed environmental chemistry, sulfate reduction rates, diversity of putative sulfur metabolizing organisms by 16S rRNA and dissimilatory sulfite reductase (dsrB) gene amplicon sequencing, and net fractionation of sulfur isotopes along a sediment transect of a hypersaline Arctic spring. In situ sulfate reduction rates yielded minimum cell-specific sulfate reduction rates <0.3 x 10−15 moles cell−1 day−1. Neither 16S rRNA nor dsrB diversity indices correlated with relatively constant (38 to 45‰) net isotope fractionation (ε34Ssulfide−sulfate). Measured ε34S values could be reproduced in a mechanistic fractionation model if 1-2% of the microbial community (10-60% of Deltaproteobacteria) were engaged in sulfate respiration, indicating heterogeneous respiratory activity within sulfate-metabolizing populations. This model indicated enzymatic kinetic diversity of Apr was more likely to correlate with sulfur fractionation than DsrB. We propose that, above a threshold alpha diversity value, the influence of the specific composition of the microbial community responsible for generating an isotope signal is overprinted by the control exerted by environmental variables on microbial physiology. Integrated genomics and post-genomics approaches in microbial ecologyMicrobial ecology and functional diversity of natural habitats Integrated genomics and post-genomics approaches in microbial ecology Microbial ecology and functional diversity of natural habitats

Introduction Wilson disease (WD) is a disorder of abnormal copper metabolism prevalent in young populations. Though there has been mention of WD in older patients, such cases are extremely rare. Herein we describe an unusual presentation of acute liver failure in a 72-year-old female. Case Report A 72-year-old woman with history significant for lupus on chronic Methotrexate presented to our institution for acute liver failure. Family and social history were unremarkable. Admission labs were AST 125, ALT 94, ALP 468, T-bilirubin 0.7, D-bilirubin 0.3, INR 1.3. Progressive decline in patient's liver function prompted liver biopsy revealing steatohepatitis, minimal fibrosis 1a/4, cholestasis, and anisonucleosis consistent with methotrexate induced hepatotoxicity versus WD (Figure 1). Patient was initially managed conservatively with working diagnosis of presumed methotrexate induced hepatotoxicity. However, suspicion for WD increased when patient developed hemolytic anemia, acute renal failure, depressed mental status and worsening jaundice. Patient underwent slit lamp examination with equivocal findings of Kaiser-Fleischer rings. Notable laboratory values included serum copper of 79 mcg/dL, 24-hour urinary copper excretion of 31 mcg/24 hr (GFR 34 at time of collection), and ceruloplasmin of 14 mg/dL. Non-ceruloplasmin bound copper was 37 pg/dL. Quantitative hepatic copper returned elevated at 298 mcg cu/g. Labs progressed to AST 124, ALT 38, ALP 475, T-bilirubin 34 .7, D-bilirubin 30.8, INR 2.58. Genetic testing with whole gene sequencing revealed heterozygosity for a single copy of a point mutation in the ATP7B gene (A to G substitution at position 226). Unfortunately, patient ultimately passed away. Discussion Wilson Disease is diagnosed on the basis of several clinical and biochemical tests. In our case, symptoms consistent with WD included cirrhosis, neuro-psychiatric depression, equivocal KaiserFleischer rings, hemolytic anemia and acute renal failure. Convincing laboratory values included low ceruloplasmin, elevated quantitative hepatic copper, elevated non-ceruloplasmin bound copper and anisonucleosis on biopsy. Genetic testing revealed a variant of unclear significance in the ATP7B gene, and recent literature has cited high alleleic heterogeneity patients with WD. This case illustrates the atypical presentation of WD in an elderly 72-year-old patient, highlighting the importance of maintaining clinical suspicion for WD even in older patients.

KEYWORD HIT We interviewed actors from the Fox-TV series, \"Class of '96\" - Jason Gedrick (he plays David Morrissey), Brandon Douglas (Whitney Reed), Gale Hansen (Samuel \"Stroke\" Dexter) and [Megan Ward] (Patty Horvath) - at Planet Hollywood in Manhattan recently. They were there donating memorabilia from the show to add to the restaurant's collection. Q. How are you similar and different to your character on the show? A. Jason: My character and I are very interested in meeting and learning about new people. But he is more down-to-earth, and I'm high strung. Brandon: I am really passionate about life and energetic like Whitney is. We're different in that I handle problems head on and try to find solutions. Whitney doesn't; he buries his emotions. He also doesn't have a strong relationship with his family and because of that emotional turmoil, he resorts to drinking. Gale: He earns the money, and I cash the paycheck. Megan: We are very similar. I've always wanted to be an actress like she does. She's a nice person and I like to think I am, too. Q. What is your favorite kind of acting? A. Jason: I like a balance of action, comedy and drama. Brandon: I've had the most satisfaction with drama. Gale: I like acting silly. Like in real life when you are with your friends and you have a crush on a girl, and you don't want her to know. Megan: I like the old musicals like \"Wizard of Oz\" and \"Sound of Music.\" I grew up doing musical theater. I'd like to do a Broadway show someday.

Q. How did you get into acting? A. When I was 15, I started taking workshops and later got an agent. Q. In real life, did you ever date the star of \"Doogie Howser, M.D.,\" Neil Patrick Harris? A. No! Q. Why did you leave that show? A. It wasn't working anymore; they ran out of story lines. Q. Do you ever compare \"Class of '96\" to \"Beverly Hills, 90210\"? A. No. I think we get that comparison from the public but not from the people who are on the show or who created it. I don't think \"Class of '96\" is anywhere near \"90210.\" We are a more reality-based show. Q. What do you think was the most important issue \"Class of '96\" has covered? A. Anti-Semitism. Q. What will happen when you all graduate in 1996? A. I don't know.

[Guy Velella], who will be back in handcuffs by dinnertime today, left his Bronx home just before 9 a.m. and climbed into a neighbor's Jaguar with his wife, Pamela. Mayor Bloomberg, who has been critical of Velella's release, replaced the obscure board's members in October. The new members voted to send Velella back to jail. Jesse Ward Fallen ex-state Se. Guy Velella leaves his Bronx home on his way to church yesterday, the day before his city- ordered and court up-held- return to Rikers Island for taking bribes.

This paper describes the design of a unique suite of mechanisms that make up the Deployment and Pointing System (DAPS) for the Neutron Star Interior Composition Explorer (NICER/SEXTANT) instrument, an X-Ray telescope, which will be mounted on the International Space Station (ISS). The DAPS system uses four stepper motor actuators to deploy the telescope box, latch it in the deployed position, and allow it to track sky targets. The DAPS gimbal architecture provides full-hemisphere coverage, and is fully re-stowable. The compact design of the mechanism allowed the majority of total instrument volume to be used for science. Override features allow DAPS to be stowed by ISS robotics.

This paper describes the design of a unique suite of mechanisms which make up the Deployment and Pointing System (DAPS) for the Neutron Star Interior Composition Explorer (NICER/SEXTANT) instrument, an X-Ray telescope, which will be mounted on the International Space Station (ISS). The DAPS system uses 4 stepper motor actuators to deploy the telescope box, latch it in the deployed position, and allow it to track sky targets. The DAPS gimbal architecture provides full-hemisphere coverage, and is fully re-stowable. The compact design of the mechanism allowed the majority of total instrument volume to be used for science. Override features allow DAPS to be stowed by ISS robotics.