2,066 research outputs found

    Differences between proposed Apollo sites: 1. Synthesis

    Get PDF
    Recent observations of the spectral reflectivity and emissivity of the five prime Apollo landing sites are evaluated in the context of similar observations of other localities on the moon and of data returned from unmanned lunar probes. We conclude that those five sites differ significantly only in minor constituents and/or relative valence states and that those differences are more modest than the differences that characterize mare regions generally. Recommendations of priorities for the five prime Apollo sites are made based on their uniqueness for sample return. Sampling of other lunar localities displaying anomalous emissivities and extreme color differences will be required to ascertain the full range of lithologies that constitute the lunar surface

    Microsatellite Development via Next-Generation Sequencing in Acacia stenophylla (Fabaceae) and Duma florulenta (Polygonaceae): Two Ecologically Important Plant Species of Australian Dryland Floodplains

    Get PDF
    Duma florulenta and Acacia stenophylla are two ecologically important but understudied species that naturally occur on the floodplains and riverbanks of Australia’s arid and semi-arid river systems. This paper describes the discovery and characterization of 12 and 13 polymorphic microsatellite markers for D. florulenta and A. stenophylla respectively. The number of alleles per locus for D. florulenta ranged from 2-12 with an average of 6.1. Across all samples, observed and expected heterozygosities ranged from 0.026 to 0.784 and 0.026 to 0.824 respectively and mean polymorphic information content was equal to 0.453. For A. stenophylla, the number of alleles per locus ranged between 2 and 8 with an overall mean of 4.8. Across all samples, observed and expected heterozygosities ranged from 0.029 to 0.650 and 0.029 to 0.761 respectively and mean polymorphic information content was 0.388. The developed suites of 12 and 13 microsatellite markers for D. florulenta and A. stenophylla respectively provide opportunity for novel research into mechanisms of gene flow, dispersal and breeding system and how they operate under the extreme variability these species are exposed to in the environments in which they live

    Martian oases? Feasibility of orbital thermal emission detection

    Get PDF
    We review the motivation for searching out modem "oases" on Mars, and examine methods of detecting them from orbit. We use the term "oasis" to refer to sites with anomalous thermal behavior at, or near the planet's surface. Such sites may be more likely than other locations on Mars to have liquid water nearby, hence the terminology reminiscent of Earth's deserts. Three types of "oases" are considered here: small-scale volcanic eruptions, hot springs, and subsurface intrusions. The general consensus is that such oases are highly unlikely on Mars today, and probably do not exist at all. How much investment is worthy of such a high-risk, unlikely return? We argue that the potential long-term importance of such a discovery does merit a significant investment. We propose a detection strategy based on a high spatial resolution infra-red thermal emission instrument, though other techniques are briefly discussed. We conclude that such an instrument could feasibly detect surface lavas, and quite likely any surface hot springs, but would not be able to unambiguously determine the presence of a buried geothermal anomaly that does not manifest itself sufficiently at the surface in one of the two other forms

    Durability of Response in Children Treated with Pegylated Interferon alfa-2a +/- Ribavirin for Chronic Hepatitis C

    Get PDF
    Objectives: No long-term data have been published on the durability of response following pegylated interferon (PegIFN) treatment in children with chronic hepatitis C. This prospective, multicenter, long-term follow-up (LTFU) study aimed to assess long-term durability of sustained virological response (SVR), long-term safety and tolerability, and the association between IL28B genotype and treatment response, in children previously treated with PegIFN alfa-2a ± ribavirin (RBV) in the PEDS-C trial. Methods: A total of 93 patients were assessed for enrollment, and 38 enrolled in the study. Patients attended 2 study visits: 5 (mean 5.6, range 4.1–6.6) and 6 (6.6, 5.1–7.7) years after treatment cessation. Standardized medical history, physical examination, and laboratory testing were performed at these visits. Reminder telephone calls were conducted at 4 and 8 months after the initial visit. Results: The LTFU cohort was the representative of the original PEDS-C cohort because both baseline and treatment characteristics were comparable. Of the 38 participants, 21 achieved SVR (responders) during the PEDS-C trial and 17 had not (nonresponders). All 21 responders maintained undetectable hepatitis C virus RNA during the LTFU (4.4–7.0 years after achieving SVR) in contrast to the nonresponders who demonstrated persistent viremia. IL28B CC genotype was associated with SVR (67% vs 30% in non-CC, P = 0.028). Conclusion: Long-term durability of SVR is excellent following PegIFN alfa-2a treatment in children with chronic hepatitis C; SVR is higher in those with IL28B CC versus non-CC

    A unified ML framework for solubility prediction across organic solvents

    Get PDF
    We report a single machine learning (ML)-based model to predict the solubility of drug/drug-like compounds across 49 organic solvents, extensible to more. By adopting a cross-solvent data structure, we enable the exploitation of valuable relational information between systems. The effect is major, with even a single experimental measurement of a solute in a different solvent being enough to significantly improve predictions on it, and successive ones improving them further. Working with a sparse dataset of only 714 experimental data points spanning 75 solutes and 49 solvents (81% sparsity), a ML-based model with a prediction RMSE of 0.75 log S (g/100 g) for unseen solutes was produced. This compares favourably with conductor-like screening model for real solvents (COSMO-RS), an industry-standard model based on thermodynamic laws, which yielded a prediction RMSE of 0.97 for the same dataset. The error for our method reduced to a mean RMSE of 0.65 when one instance of the solute (in a different solvent) was included in the training data; this iteratively reduced further to 0.60, 0.57 and 0.56 when two, three and four instances were available, respectively. This standard of performance not only meets or exceeds those of alternative ML-based solubility models insofar as they can be compared but reaches the perceived ceiling for solubility prediction models of this type. In parallel, we assess the performance of the model with and without the addition of COSMO-RS output as an additional descriptor. We find that a significant benefit is gained from its addition, indicating that mechanistic methods can bring insight that simple molecular descriptors cannot and should be incorporated into a data-driven prediction of molecular properties where possible

    The FaceBase Consortium: A comprehensive program to facilitate craniofacial research

    Get PDF
    The FaceBase Consortium consists of ten interlinked research and technology projects whose goal is to generate craniofacial research data and technology for use by the research community through a central data management and integrated bioinformatics hub. Funded by the National Institute of Dental and Craniofacial Research (NIDCR) and currently focused on studying the development of the middle region of the face, the Consortium will produce comprehensive datasets of global gene expression patterns, regulatory elements and sequencing; will generate anatomical and molecular atlases; will provide human normative facial data and other phenotypes; conduct follow up studies of a completed genome-wide association study; generate independent data on the genetics of craniofacial development, build repositories of animal models and of human samples and data for community access and analysis; and will develop software tools and animal models for analyzing and functionally testing and integrating these data. The FaceBase website (http://www.facebase.org) will serve as a web home for these efforts, providing interactive tools for exploring these datasets, together with discussion forums and other services to support and foster collaboration within the craniofacial research community

    Baseline ultrasound and clinical correlates in children with cystic fibrosis.

    Get PDF
    Objective: To investigate the relationship between abdominal ultrasound (US) findings and demographic, historical and clinical features in children with CF. Study design: Children age 3-12 years with CF without known cirrhosis, were enrolled in a prospective, multi-center study of US to predict hepatic fibrosis. Consensus US patterns were assigned by 3 radiologists as normal, heterogeneous, homogeneous, or cirrhosis. Data were derived from direct collection and U.S. or Toronto CF registries. Chi-square or ANOVA were used to compare variables among US groups and between normal and abnormal. Logistic regression was used to study risk factors for having abnormal US. Results: Findings in 719 subjects were normal (n=590, 82.1%), heterogeneous (64, 8.9%), homogeneous (41, 5.7%), and cirrhosis (24, 3.3%). Cirrhosis (p=0.0004), homogeneous (p<0.0001) and heterogeneous (p=0.03) were older than normal. More males were heterogeneous (p=0.001). More heterogeneous (15.0%, p=0.009) and cirrhosis (25.0%, p=0.005) ha

    Possible Case of Maternal Transmission of Feline Spongiform Encephalopathy in a Captive Cheetah

    Get PDF
    Feline spongiform encephalopathy (FSE) is considered to be related to bovine spongiform encephalopathy (BSE) and has been reported in domestic cats as well as in captive wild cats including cheetahs, first in the United Kingdom (UK) and then in other European countries. In France, several cases were described in cheetahs either imported from UK or born in France. Here we report details of two other FSE cases in captive cheetah including a 2nd case of FSE in a cheetah born in France, most likely due to maternal transmission. Complete prion protein immunohistochemical study on both brains and peripheral organs showed the close likeness between the two cases. In addition, transmission studies to the TgOvPrP4 mouse line were also performed, for comparison with the transmission of cattle BSE. The TgOvPrP4 mouse brains infected with cattle BSE and cheetah FSE revealed similar vacuolar lesion profiles, PrPd brain mapping with occurrence of typical florid plaques. Collectively, these data indicate that they harbor the same strain of agent as the cattle BSE agent. This new observation may have some impact on our knowledge of vertical transmission of BSE agent-linked TSEs such as in housecat FSE, or vCJD
    • …
    corecore