611 research outputs found

    Statistics for the Evaluation and Comparison of Models

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    Copyright 1985 by the American Geophysical Union.Procedures that may be used to evaluate the operational performance of a wide spectrum of geophysical models are introduced. Primarily using a complementary set of difference measures, both model accuracy and precision can be meaningfully estimated, regardless of whether the model predictions are manifesteda s scalars,d irections,o r vectors.I t is additionally suggestedth at the reliability of the accuracy and precision measures can be determined from bootstrap estimates of confidence and significance. Recommendedp roceduresa re illustrated with a comparativee valuation of two models that estimate wind velocity over the South Atlantic Bight

    Predictive Modeling Techniques in Prostate Cancer

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    A number of new predictive modeling techniques have emerged in the past several years. These methods can be used independently or in combination with traditional modeling techniques to produce useful tools for the management of prostate cancer. Investigators should be aware of these techniques and avail themselves of their potentially useful properties. This review outlines selected predictive methods that can be used to develop models that may be useful to patients and clinicians for prostate cancer management.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/63147/1/10915360152745812.pd

    Constraints on the Thermal Contents of the X-ray Cavities of Cluster MS 0735.6+7421 with Sunyaev-Zel'dovich Effect Observations

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    Outbursts from active galactic nuclei (AGN) can inflate cavities in the intracluster medium (ICM) of galaxy clusters and are believed to play the primary role in offsetting radiative cooling in the ICM. However, the details of how the energy from AGN feedback thermalizes to heat the ICM is not well understood, partly due to the unknown composition and energetics of the cavities. The Sunyaev-Zel'dovich (SZ) effect, a measure of the integrated pressure along the line of sight, provides a means of measuring the thermal contents of the cavities, to discriminate between thermal, nonthermal, and other sources of pressure support. Here we report measurements of the SZ effect at 30 GHz toward the galaxy cluster MS 0735.6+7421 (MS0735), using the Combined Array for Research in Millimeter-wave Astronomy (CARMA). MS0735 hosts the most energetic AGN outburst known and lobes of radio synchrotron emission coincident with a pair of giant X-ray cavities ∌200\sim 200 across. Our CARMA maps show a clear deficit in the SZ signal coincident with the X-ray identified cavities, when compared to a smooth X-ray derived pressure model. We find that the cavities have very little SZ-contributing material, suggesting that they are either supported by very diffuse thermal plasma with temperature in excess of hundreds of keV, or are not supported thermally. Our results represent the first detection (with 4.4σ4.4 \sigma significance) of this phenomenon with the SZ effect.Comment: 15 pages, 9 figures, submitted to ApJ Jun 2018, Accepted Dec 2018, Published Jan 2019. This is the version of the article before editing, as submitted by an author to ApJ. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The Version of Record is available online at https://doi.org/10.3847/1538-4357/aaf88

    Poliovirus RNA Polymerase Mutation 3D-M394T Results in a Temperature-Sensitive Defect in RNA Synthesis

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    AbstractMutant ts10 is an RNA-negative temperature-sensitive mutant of Mahoney type 1 poliovirus. Mutant ts10 3Dpolwas purified from infected cells and was shown to be rapidly heat-inactivated at 45° when compared to wild-type polymerase. Sequencing of mutant ts10 genomic RNA revealed a U to C transition at nt 7167 resulting in an amino acid change of methionine 394 of 3Dpolto threonine. The 3D-M394T mutation was engineered into a wild-type infectious clone of poliovirus type 1. The resultant mutant virus, 3D-105, had a temperature-sensitive phenotype in plaque assays. The translation and replication of wild-type, ts10, and 3D-105 virion RNAs were all characterized in HeLa S10 translation-RNA replication reactionsin vitro.The optimum temperatures for the replication of the wild-type and mutant viral RNAs in the HeLa S10 translation-replication reactions were 37 and 34°, respectively. To characterize the temperature-sensitive defect in the replication of the mutant RNA, we used preinitiation RNA replication complexes which were formed in HeLa S10in vitroreactions containing guanidine HCl. Negative-strand RNA synthesis in 3D-M394T mutant preinitiation replication complexes was normal at 34° but was rapidly and irreversibly inhibited at 39.5°. To differentiate between the initiation and elongation steps in RNA replication, we compared the elongation rates in mutant and wild-type replication complexes at 39.5°. The results showed that the elongation rates for nascent negative strands in both the mutant and wild-type replication complexes were identical. Therefore, the results indicate that the heat-sensitive step in negative-strand synthesis exhibited by the 3D-M394T replication complexes is in the initiation of RNA synthesis and not in the elongation of nascent chains

    Preferential regulation of stably expressed genes in the human genome suggests a widespread expression buffering role of microRNAs

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    In this study, we comprehensively explored the stably expressed genes (SE genes) and fluctuant genes (FL genes) in the human genome by a meta-analysis of large scale microarray data. We found that these genes have distinct function distributions. miRNA targets are shown to be significantly enriched in SE genes by using propensity analysis of miRNA regulation, supporting the hypothesis that miRNAs can buffer whole genome expression fluctuation. The expression-buffering effect of miRNA is independent of the target site number within the 3'-untranslated region. In addition, we found that gene expression fluctuation is positively correlated with the number of transcription factor binding sites in the promoter region, which suggests that coordination between transcription factors and miRNAs leads to balanced responses to external perturbations

    A phylum-level phylogenetic classification of zygomycete fungi based on genome-scale data

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    Zygomycete fungi were classified as a single phylum, Zygomycota, based on sexual reproduction by zygospores, frequent asexual reproduction by sporangia, absence of multicellular sporocarps, and production of coenocytic hyphae, all with some exceptions. Molecular phylogenies based on one or a few genes did not support the monophyly of the phylum, however, and the phylum was subsequently abandoned. Here we present phylogenetic analyses of a genome-scale data set for 46 taxa, including 25 zygomycetes and 192 proteins, and we demonstrate that zygomycetes comprise two major clades that form a paraphyletic grade. A formal phylogenetic classification is proposed herein and includes two phyla, six subphyla, four classes and 16 orders. On the basis of these results, the phyla Mucoromycota and Zoopagomycota are circumscribed. Zoopagomycota comprises Entomophtoromycotina, Kickxellomycotina and Zoopagomycotina; it constitutes the earliest diverging lineage of zygomycetes and contains species that are primarily parasites and pathogens of small animals (e.g. amoeba, insects, etc.) and other fungi, i.e. mycoparasites. Mucoromycota comprises Glomeromycotina, Mortierellomycotina, and Mucoromycotina and is sister to Dikarya. It is the more derived clade of zygomycetes and mainly consists of mycorrhizal fungi, root endophytes, and decomposers of plant material. Evolution of trophic modes, morphology, and analysis of genome-scale data are discussed

    Lipidomic and transcriptional analysis of the Linoleoyl-omega-Hydroxyceramide biosynthetic pathway in human psoriatic lesions

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    A complex assembly of lipids including fatty acids, cholesterol and ceramides is vital to the integrity of the mammalian epidermal barrier. The formation of this barrier requires oxidation of the substrate fatty acid, linoleate (LA), which is initiated by the enzyme 12R-lipoxygenase (LOX). In the epidermis, unoxidized LA is primarily found in long chain acylceramides termed esterified omega-hydroxy sphingosine/phytosphingosine/hydroxysphingosine (EOS/EOP/EOH, collectively EOx). The precise structure and localization of LOX-oxidised EOx in the human epidermis is unknown, as is their regulation in diseases such as psoriasis, one of the most common inflammatory diseases affecting the skin. Here, using precursor LC/MS/MS, we characterized multiple intermediates of EOx, including 9-HODE, 9,10-epoxy-13-HOME, and 9,10,13-TriHOME in healthy human epidermis likely to be formed via the epidermal LOX pathways. The top layers of the skin contained more LA, 9-HODE, and 9,10,13-TriHOME EOSs, while 9,10-epoxy-13-HOME EOS was more prevalent deeper in the stratum corneum. In psoriatic lesions, levels of native EOx and free HODEs and HOMEs were significantly elevated, while oxidized species were generally reduced. A transcriptional network analysis of human psoriatic lesions identified significantly elevated expression of the entire biosynthetic/metabolic pathway for oxygenated ceramides, suggesting a regulatory function for EOx lipids in reconstituting epidermal integrity. The role of these new lipids in progression or resolution of psoriasis is currently unknown. We also discovered the central coordinated role of the zinc finger protein transcription factor, ZIC1, in driving the phenotype of this disease. In summary, long-chain oxygenated ceramide metabolism is dysregulated at the lipidomic level in psoriasis, likely driven by the transcriptional differences also observed, and we identified ZIC1 as a potential regulatory target for future therapeutic interventions

    Mechanisms of Orthopnoea in Patients with Advanced COPD.

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    Many patients with severe chronic obstructive pulmonary disease (COPD) report unpleasant respiratory sensation at rest, further amplified by adoption of supine position (orthopnoea). The mechanisms of this acute symptomatic deterioration are poorly understood.16 patients with advanced COPD and history of orthopnoea and 16 age- and sex-matched healthy controls (CTRL) underwent pulmonary function tests and detailed sensory-mechanical measurements including inspiratory neural drive (IND, diaphragm electromyography), oesophageal and gastric pressures in sitting and supine positions.Patients had severe airflow obstruction (FEV1: 40±18%predicted) and lung hyperinflation. Regardless of the position, patients had lower inspiratory capacity (IC) and higher IND for a given tidal volume (i.e. greater neuromechanical dissociation (NMD)), higher intensity of breathing discomfort, minute ventilation (⩒E) and breathing frequency (Fb) compared with CTRL (all p<0.05). In supine position in CTRL (versus sitting erect): IC increased (by 0.48L) with a small drop in ⩒E mainly due to reduced Fb (all p<0.05). By contrast, patients' IC remained unaltered, but dynamic lung compliance decreased (p<0.05) in the supine position. Breathing discomfort, inspiratory work of breathing, inspiratory effort, IND, NMD and neuro-ventilatory uncoupling all increased in COPD in the supine position (p<0.05), but not in CTRL. Orthopnoea was associated with acute changes in IND (r=0.65, p=0.01), neuro-ventilatory uncoupling (r=0.76, p=0.001) and NMD (r=0.73, p=0.002).In COPD, onset of orthopnoea coincided with an abrupt increase in elastic loading of the inspiratory muscles in recumbency in association with increased IND and greater neuromechanical dissociation of the respiratory system

    Moderators, Mediators, and Prognostic Indicators of Treatment With Hip Arthroscopy or Physical Therapy for Femoroacetabular Impingement Syndrome: Secondary Analyses From the Australian FASHIoN Trial.

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    BACKGROUND Although randomized controlled trials comparing hip arthroscopy with physical therapy for the treatment of femoroacetabular impingement (FAI) syndrome have emerged, no studies have investigated potential moderators or mediators of change in hip-related quality of life. PURPOSE To explore potential moderators, mediators, and prognostic indicators of the effect of hip arthroscopy and physical therapy on change in 33-item international Hip Outcome Tool (iHOT-33) score for FAI syndrome. STUDY DESIGN Cohort study; Level of evidence, 2. METHODS Overall, 99 participants were recruited from the clinics of orthopaedic surgeons and randomly allocated to treatment with hip arthroscopy or physical therapy. Change in iHOT-33 score from baseline to 12 months was the dependent outcome for analyses of moderators, mediators, and prognostic indicators. Variables investigated as potential moderators/prognostic indicators were demographic variables, symptom duration, alpha angle, lateral center-edge angle (LCEA), Hip Osteoarthritis MRI Scoring System (HOAMS) for selected magnetic resonance imaging (MRI) features, and delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) score. Potential mediators investigated were change in chosen bony morphology measures, HOAMS, and dGEMRIC score from baseline to 12 months. For hip arthroscopy, intraoperative procedures performed (femoral ostectomy ± acetabular ostectomy ± labral repair ± ligamentum teres debridement) and quality of surgery graded by a blinded surgical review panel were investigated for potential association with iHOT-33 change. For physical therapy, fidelity to the physical therapy program was investigated for potential association with iHOT-33 change. RESULTS A total of 81 participants were included in the final moderator/prognostic indicator analysis and 85 participants in the final mediator analysis after exclusion of those with missing data. No significant moderators or mediators of change in iHOT-33 score from baseline to 12 months were identified. Patients with smaller baseline LCEA (ÎČ = -0.82; P = .034), access to private health care (ÎČ = 12.91; P = .013), and worse baseline iHOT-33 score (ÎČ = -0.48; P < .001) had greater iHOT-33 improvement from baseline to 12 months, irrespective of treatment allocation, and thus were prognostic indicators of treatment response. Unsatisfactory treatment fidelity was associated with worse treatment response (ÎČ = -24.27; P = .013) for physical therapy. The quality of surgery and procedures performed were not associated with iHOT-33 change for hip arthroscopy (P = .460-.665 and P = .096-.824, respectively). CONCLUSION No moderators or mediators of change in hip-related quality of life were identified for treatment of FAI syndrome with hip arthroscopy or physical therapy in these exploratory analyses. Patients who accessed the Australian private health care system, had smaller LCEAs, and had worse baseline iHOT-33 scores, experienced greater iHOT-33 improvement, irrespective of treatment allocation
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