901 research outputs found
NASA's Turbofan Engine Concept Study for a Next-Generation Single-Aisle Transport: Presentation to ICAO's Noise Technology Independent Expert Panel
No abstract availabl
Consensus Panel on a Cochlear Coordinate System Applicable in Histologic, Physiologic, and Radiologic Studies of the Human Cochlea
HypothesisâAn objective cochlear framework, for evaluation of the cochlear anatomy and description of the position of an implanted cochlear implant electrode, would allow the direct comparison of measures performed within the various sub-disciplines involved in cochlear implant research. BackgroundâResearch on the human cochlear anatomy in relation to tonotopy and cochlear implantation is conducted by specialists from numerous disciplines such as histologists, surgeons, physicists, engineers, audiologists and radiologists. To allow accurate comparisons between and combinations of previous and forthcoming scientific and clinical studies, cochlear structures and electrode positions must be specified in a consistent manner. MethodsâResearchers with backgrounds in the various fields of inner ear research as well as representatives of the different manufacturers of cochlear implants (Advanced Bionics Corp, Med-El, Cochlear Corp) were involved in consensus meetings held in Dallas, March 2005 and Asilomar, August 2005. Existing coordinate systems were evaluated and requisites for an objective cochlear framework were discussed. ResultsâThe consensus panel agreed upon a 3-dimensional, cylindrical coordinate system of the cochlea using the âCochlear Viewâ as a basis and choosing a z-axis through the modiolus. The zero reference angle was chosen at the centre of the round window, which has a close relationship to the basal end of the Organ of Corti. ConclusionsâConsensus was reached on an objective cochlear framework, allowing the outcomes of studies from different fields of research to be compared directly
Overview of the NASA STARC-ABL (Rev. B) Advanced Concept
No abstract availabl
Genome-wide association analyses of physical activity and sedentary behavior provide insights into underlying mechanisms and roles in disease prevention
Although physical activity and sedentary behavior are moderately heritable, little is known about the mechanisms that influence these traits. Combining data for up to 703,901 individuals from 51 studies in a multi-ancestry meta-analysis of genome-wide association studies yields 99 loci that associate with self-reported moderate-to-vigorous intensity physical activity during leisure time (MVPA), leisure screen time (LST) and/or sedentary behavior at work. Loci associated with LST are enriched for genes whose expression in skeletal muscle is altered by resistance training. A missense variant in ACTN3 makes the alpha-actinin-3 filaments more flexible, resulting in lower maximal force in isolated type IIA muscle fibers, and possibly protection from exercise-induced muscle damage. Finally, Mendelian randomization analyses show that beneficial effects of lower LST and higher MVPA on several risk factors and diseases are mediated or confounded by body mass index (BMI). Our results provide insights into physical activity mechanisms and its role in disease prevention. Multi-ancestry meta-analyses of genome-wide association studies for self-reported physical activity during leisure time, leisure screen time, sedentary commuting and sedentary behavior at work identify 99 loci associated with at least one of these traits
Ebola Zaire Virus Blocks Type I Interferon Production by Exploiting the Host SUMO Modification Machinery
Ebola Zaire virus is highly pathogenic for humans, with case fatality rates approaching 90% in large outbreaks in Africa. The virus replicates in macrophages and dendritic cells (DCs), suppressing production of type I interferons (IFNs) while inducing the release of large quantities of proinflammatory cytokines. Although the viral VP35 protein has been shown to inhibit IFN responses, the mechanism by which it blocks IFN production has not been fully elucidated. We expressed VP35 from a mouse-adapted variant of Ebola Zaire virus in murine DCs by retroviral gene transfer, and tested for IFN transcription upon Newcastle Disease virus (NDV) infection and toll-like receptor signaling. We found that VP35 inhibited IFN transcription in DCs following these stimuli by disabling the activity of IRF7, a transcription factor required for IFN transcription. By yeast two-hybrid screens and coimmunoprecipitation assays, we found that VP35 interacted with IRF7, Ubc9 and PIAS1. The latter two are the host SUMO E2 enzyme and E3 ligase, respectively. VP35, while not itself a SUMO ligase, increased PIAS1-mediated SUMOylation of IRF7, and repressed Ifn transcription. In contrast, VP35 did not interfere with the activation of NF-ÎșB, which is required for induction of many proinflammatory cytokines. Our findings indicate that Ebola Zaire virus exploits the cellular SUMOylation machinery for its advantage and help to explain how the virus overcomes host innate defenses, causing rapidly overwhelming infection to produce a syndrome resembling fulminant septic shock
Bauen in Brasilien
Im Herbst 2014 fand die groĂe Exkursion 2014 der FakultĂ€t Bauingenieurwesen der HTWG Konstanz nach Brasilien unter der Leitung von Prof. Dr. Horst Werkle und Prof. Dr. Peter Hirschmann statt. Auf dem Programm stand der Besuch der StĂ€dte Sao Paulo, Rio de Janeiro und Iguacu. Der Bericht schildert den Besuch interessanter Baustellen und groĂer Bauprojekte wie des im Bau befindlichen futuristisch anmutenden âMuseum of Tomorrowâ, des Maracana-Stadions mit seiner neuen Membrandachkonstruktion sowie des zweitgröĂten Wasserkraftwerks der Welt
Entrapment of Viral Capsids in Nuclear PML Cages Is an Intrinsic Antiviral Host Defense against Varicella-Zoster Virus
The herpesviruses, like most other DNA viruses, replicate in the host cell nucleus. Subnuclear domains known as promyelocytic leukemia protein nuclear bodies (PML-NBs), or ND10 bodies, have been implicated in restricting early herpesviral gene expression. These viruses have evolved countermeasures to disperse PML-NBs, as shown in cells infected in vitro, but information about the fate of PML-NBs and their functions in herpesvirus infected cells in vivo is limited. Varicella-zoster virus (VZV) is an alphaherpesvirus with tropism for skin, lymphocytes and sensory ganglia, where it establishes latency. Here, we identify large PML-NBs that sequester newly assembled nucleocapsids (NC) in neurons and satellite cells of human dorsal root ganglia (DRG) and skin cells infected with VZV in vivo. Quantitative immuno-electron microscopy revealed that these distinctive nuclear bodies consisted of PML fibers forming spherical cages that enclosed mature and immature VZV NCs. Of six PML isoforms, only PML IV promoted the sequestration of NCs. PML IV significantly inhibited viral infection and interacted with the ORF23 capsid surface protein, which was identified as a target for PML-mediated NC sequestration. The unique PML IV C-terminal domain was required for both capsid entrapment and antiviral activity. Similar large PML-NBs, termed clastosomes, sequester aberrant polyglutamine (polyQ) proteins, such as Huntingtin (Htt), in several neurodegenerative disorders. We found that PML IV cages co-sequester HttQ72 and ORF23 protein in VZV infected cells. Our data show that PML cages contribute to the intrinsic antiviral defense by sensing and entrapping VZV nucleocapsids, thereby preventing their nuclear egress and inhibiting formation of infectious virus particles. The efficient sequestration of virion capsids in PML cages appears to be the outcome of a basic cytoprotective function of this distinctive category of PML-NBs in sensing and safely containing nuclear aggregates of aberrant proteins
BLOOM: A 176B-Parameter Open-Access Multilingual Language Model
Large language models (LLMs) have been shown to be able to perform new tasks
based on a few demonstrations or natural language instructions. While these
capabilities have led to widespread adoption, most LLMs are developed by
resource-rich organizations and are frequently kept from the public. As a step
towards democratizing this powerful technology, we present BLOOM, a
176B-parameter open-access language model designed and built thanks to a
collaboration of hundreds of researchers. BLOOM is a decoder-only Transformer
language model that was trained on the ROOTS corpus, a dataset comprising
hundreds of sources in 46 natural and 13 programming languages (59 in total).
We find that BLOOM achieves competitive performance on a wide variety of
benchmarks, with stronger results after undergoing multitask prompted
finetuning. To facilitate future research and applications using LLMs, we
publicly release our models and code under the Responsible AI License
Target genes, variants, tissues and transcriptional pathways influencing human serum urate levels.
Elevated serum urate levels cause gout and correlate with cardiometabolic diseases via poorly understood mechanisms. We performed a trans-ancestry genome-wide association study of serum urate in 457,690 individuals, identifying 183 loci (147 previously unknown) that improve the prediction of gout in an independent cohort of 334,880 individuals. Serum urate showed significant genetic correlations with many cardiometabolic traits, with genetic causality analyses supporting a substantial role for pleiotropy. Enrichment analysis, fine-mapping of urate-associated loci and colocalization with gene expression in 47 tissues implicated the kidney and liver as the main target organs and prioritized potentially causal genes and variants, including the transcriptional master regulators in the liver and kidney, HNF1A and HNF4A. Experimental validation showed that HNF4A transactivated the promoter of ABCG2, encoding a major urate transporter, in kidney cells, and that HNF4A p.Thr139Ile is a functional variant. Transcriptional coregulation within and across organs may be a general mechanism underlying the observed pleiotropy between urate and cardiometabolic traits.The Genotype-Tissue Expression (GTEx) Project was supported by the Common Fund of the Office of the Director of the National Institutes of Health, and by NCI, NHGRI, NHLBI, NIDA, NIMH, and NINDS. Variant annotation was supported by software resources provided via the Caché Campus program of the InterSystems GmbH to Alexander Teumer
Automated quantitative MRI volumetry reports support diagnostic interpretation in dementia: a multi-rater, clinical accuracy study
Objectives: We examined whether providing a quantitative report (QReport) of regional brain volumes improves radiologistsâ accuracy and confidence in detecting volume loss, and in differentiating Alzheimerâs disease (AD) and frontotemporal dementia (FTD), compared with visual assessment alone. Methods: Our forced-choice multi-rater clinical accuracy study used MRI from 16 AD patients, 14 FTD patients, and 15 healthy controls; age range 52â81. Our QReport was presented to raters with regional grey matter volumes plotted as percentiles against data from a normative population (n = 461). Nine raters with varying radiological experience (3 each: consultants, registrars, ânon-clinical image analystsâ) assessed each case twice (with and without the QReport). Raters were blinded to clinical and demographic information; they classified scans as ânormalâ or âabnormalâ and if âabnormalâ as âADâ or âFTDâ. Results: The QReport improved sensitivity for detecting volume loss and AD across all raters combined (p = 0.015* and p = 0.002*, respectively). Only the consultant groupâs accuracy increased significantly when using the QReport (p =Â 0.02*). Overall, ratersâ agreement (Cohenâs Îș) with the âgold standardâ was not significantly affected by the QReport; only the consultant group improved significantly (Îșs 0.41â0.55, p =Â 0.04*). Cronbachâs alpha for interrater agreement improved from 0.886 to 0.925, corresponding to an improvement from âgoodâ to âexcellentâ. Conclusion: Our QReport referencing single-subject results to normative data alongside visual assessment improved sensitivity, accuracy, and interrater agreement for detecting volume loss. The QReport was most effective in the consultants, suggesting that experience is needed to fully benefit from the additional information provided by quantitative analyses. Key Points: âą The use of quantitative report alongside routine visual MRI assessment improves sensitivity and accuracy for detecting volume loss and AD vs visual assessment alone. âą Consultant neuroradiologistsâ assessment accuracy and agreement (kappa scores) significantly improved with the use of quantitative atrophy reports. âą First multi-rater radiological clinical evaluation of visual quantitative MRI atrophy report for use as a diagnostic aid in dementia
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