167 research outputs found
Upper limits for undetected trace species in the stratosphere of Titan
In this paper we describe a first quantitative search for several molecules
in Titan's stratosphere in Cassini CIRS infrared spectra. These are: ammonia
(NH3), methanol (CH3OH), formaldehyde (H2CO), and acetonitrile (CH3CN), all of
which are predicted by photochemical models but only the last of which
observed, and not in the infrared. We find non-detections in all cases, but
derive upper limits on the abundances from low-noise observations at 25{\deg}S
and 75{\deg}N. Comparing these constraints to model predictions, we conclude
that CIRS is highly unlikely to see NH3 or CH3OH emissions. However, CH3CN and
H2CO are closer to CIRS detectability, and we suggest ways in which the
sensitivity threshold may be lowered towards this goal.Comment: 11 pages plus 6 figure file
The Science Case for a Return to Enceladus
The plume of Enceladus is unique in the solar system in providing direct access to fresh material from an
extraterrestrial subsurface ocean. The Cassini Mission, though not specifically designed for it, was able to take
advantage of the plume to conduct the best characterization to date of an extraterrestrial ocean. Evidence gathered
from multiple instruments points to a global, subsurface liquid water ocean rich in salts and organic compounds,
with water-rock interactions occurring presumably in hydrothermal systems at or below the moon’s sea floor.
Meeting the criteria of “extended regions of liquid water, conditions favorable for the assembly of complex organic
molecules, and energy source(s) to sustain metabolism,” the ocean of Enceladus can therefore be considered
habitable. It is also the only confirmed place beyond the Earth where we can easily sample fresh material from a
demonstrably habitable environment without the complications of digging or drilling. The next step is to
investigate whether Enceladus’ ocean is actually inhabited. Here, we summarize the evidence for Enceladus’ ocean
and its habitability, identify constraints and outstanding questions on the detectability of life within its ocean, and
recommend a return to Enceladus with a dedicated search-for-life mission (or missions)
A database of marine phytoplankton abundance, biomass and species composition in Australian waters
There have been many individual phytoplankton datasets collected across Australia since the mid 1900s, but most are unavailable to the research community. We have searched archives, contacted researchers, and scanned the primary and grey literature to collate 3,621,847 records of marine phytoplankton species from Australian waters from 1844 to the present. Many of these are small datasets collected for local questions, but combined they provide over 170 years of data on phytoplankton communities in Australian waters. Units and taxonomy have been standardised, obviously erroneous data removed, and all metadata included. We have lodged this dataset with the Australian Ocean Data Network (http://portal.aodn.org.au/) allowing public access. The Australian Phytoplankton Database will be invaluable for global change studies, as it allows analysis of ecological indicators of climate change and eutrophication (e.g., changes in distribution; diatom:dinoflagellate ratios). In addition, the standardised conversion of abundance records to biomass provides modellers with quantifiable data to initialise and validate ecosystem models of lower marine trophic levels
Parental Child Care in Single Parent, Cohabiting, and Married Couple Families: Time Diary Evidence from the United States and the United Kingdom
Social network properties and self-rated health in later life: comparisons from the Korean social life, health, and aging project and the national social life, health and aging project
New genetic loci link adipose and insulin biology to body fat distribution.
Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms
Effect of combined psycho-physiological stretching and breathing therapy on sexual satisfaction
Application of Ligninolytic Enzymes in the Production of Biofuels from Cotton Wastes
The application of ligninolytic fungi and enzymes is an option to overcome the issues related with the production of biofuels using cotton wastes. In this dissertation, the ligninolytic fungus and enzymes were evaluated as pretreatment for the biochemical conversion of Cotton Gin Trash (CGT) in ethanol and as a treatment for the transformation of cotton wastes biochar in other substances.
In biochemical conversion, seven combinations of three pretreatments (ultrasonication, liquid hot water and ligninolytic enzymes) were evaluated on CGT. The best results were achieved by the sequential combination of ultrasonication, hot water, and ligninolytic enzymes with an improvement of 10% in ethanol yield. To improve these results, alkaline-ultrasonication was evaluated. Additionally, Fourier Transform Infrared (FT-IR) and principal component analysis (PCA) were employed as fast methodology to identify structural differences in the biomass. The combination of ultrasonication-alkali hydrolysis, hot liquid water, and ligninolytic enzymes using 15% of NaOH improved 35% ethanol yield compared with the original treatment. Additionally, FT-IR and PCA identified modifications in the biomass structure after different types of pretreatments and conditions.
In thermal conversion, this study evaluated the biodepolymerization of cotton wastes biochar using chemical and biological treatments. The chemical depolymerization evaluated three chemical agents (KMnO4, H2SO4, and NaOH), with three concentrations and two environmental conditions. The sulfuric acid treatments performed the largest transformations of the biochar solid phase; whereas, the KMnO4 treatments achieved the largest depolymerizations. The compounds released into the liquid phase were correlated with fulvic and humic acids and silicon compounds.
The biological depolymerization utilized four ligninolytic fungi Phanerochaete chrysosporium, Ceriporiopsis subvermispora, Postia placenta, and Bjerkandera adusta. The greatest depolymerization was obtained by C. subvermispora. The depolymerization kinetics of C. subvermispora evidenced the production of laccase and manganese peroxidase and a correlation between depolymerization and production of ligninolytic enzymes. The modifications obtained in the liquid and solid phases showed the production of humic and fulvic acids from the cultures with C. subvermispora.
The results of this research are the initial steps for the development of new processes using the ligninolytic fungus and their enzymes for the production of biofuels from cotton wastes
Association Between Chromosome 9p21 Variants and the Ankle-Brachial Index Identified by a Meta-Analysis of 21 Genome-Wide Association Studies
Genetic determinants of peripheral arterial disease (PAD) remain largely unknown. To identify genetic variants associated with the ankle-brachial index (ABI), a noninvasive measure of PAD, we conducted a meta-analysis of genome-wide association study data from 21 population-based cohorts
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