2,992 research outputs found
Evaluation of exercises designed to improve children's use of descriptive words in oral language
Thesis (Ed.M.)--Boston Universit
Hypercube matrix computation task
A major objective of the Hypercube Matrix Computation effort at the Jet Propulsion Laboratory (JPL) is to investigate the applicability of a parallel computing architecture to the solution of large-scale electromagnetic scattering problems. Three scattering analysis codes are being implemented and assessed on a JPL/California Institute of Technology (Caltech) Mark 3 Hypercube. The codes, which utilize different underlying algorithms, give a means of evaluating the general applicability of this parallel architecture. The three analysis codes being implemented are a frequency domain method of moments code, a time domain finite difference code, and a frequency domain finite elements code. These analysis capabilities are being integrated into an electromagnetics interactive analysis workstation which can serve as a design tool for the construction of antennas and other radiating or scattering structures. The first two years of work on the Hypercube Matrix Computation effort is summarized. It includes both new developments and results as well as work previously reported in the Hypercube Matrix Computation Task: Final Report for 1986 to 1987 (JPL Publication 87-18)
Wavelength-scale stationary-wave integrated Fourier-transform spectrometry
Spectrometry is a general physical-analysis approach for investigating
light-matter interactions. However, the complex designs of existing
spectrometers render them resistant to simplification and miniaturization, both
of which are vital for applications in micro- and nanotechnology and which are
now undergoing intensive research. Stationary-wave integrated Fourier-transform
spectrometry (SWIFTS)-an approach based on direct intensity detection of a
standing wave resulting from either reflection (as in the principle of colour
photography by Gabriel Lippmann) or counterpropagative interference
phenomenon-is expected to be able to overcome this drawback. Here, we present a
SWIFTS-based spectrometer relying on an original optical near-field detection
method in which optical nanoprobes are used to sample directly the evanescent
standing wave in the waveguide. Combined with integrated optics, we report a
way of reducing the volume of the spectrometer to a few hundreds of cubic
wavelengths. This is the first attempt, using SWIFTS, to produce a very small
integrated one-dimensional spectrometer suitable for applications where
microspectrometers are essential
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Reduced Purkinje cell number in essential tremor : a postmortem study
Background: Clinical and functional imaging evidence suggests that cerebellar dysfunction occurs in essential tremor (ET). In recent postmortem studies, we documented increased numbers of torpedoes (Purkinje cell axonal swellings) in ET patients without Lewy bodies. Purkinje cell loss, however, has never been rigorously assessed. Objective: To quantitatively assess the number of Purkinje cells in brains of ET patients and similarly aged controls. Methods: Postmortem cerebellar tissue was available in 14 ET cases (6 with Lewy bodies and 8 without Lewy bodies) and 11 controls. Calbindin immunohistochemistry was performed on paraffin sections of the cerebellum. Images were digitally recorded and blinded measurements of the number of Purkinje cells per millimeter of cell layer (linear density) were made. Results: Purkinje cell linear density was inversely correlated with age (r=-0.53, P=.006) and number of torpedoes (r=-0.42, P=.04). Purkinje cell linear density differed by diagnosis (mean [SD], controls, 3.46 [1.27] cells/mm; ET cases with Lewy bodies, 3.33 [1.06] cells/mm; and ET cases without Lewy bodies, 2.14 [0.82] cells/mm; P=.04), with the most significant difference between ET cases without Lewy bodies and controls, where the reduction was 38.2% (P=.04). In an adjusted linear regression analysis that compared ET cases without Lewy bodies with controls, decreased linear density (outcome variable) was associated with ET (β=.56, P=.03). Conclusions: We demonstrated a reduction in Purkinje cell number in the brains of patients with ET who do not have Lewy bodies. These data further support the view that the cerebellum is anatomically, as well as functionally, abnormal in these ET cases
Regulatory Developments in Structural Keel Design:A Revised ISO 12215-9
The design of yacht keel structures is governed by the ISO 12215-9:2012, which is concerned with the loads and scantlings of monohull sailing craft appendages up to 24 m hull length. However, the significant advances in sailing yacht performance, appendages design, materials and manufacturing of the past decade now warrant a revision of this crucial international standard. Consequently, this paper presents the technical background and impending developments in regulatory yacht keel structures. The proposed revisions include (i) a new load case for lateral impact; (ii) compulsory and more stringent fatigue assessment; (iii) enhanced structural arrangements for bolts and backing plates; and (iv) informative guidelines regarding keel installation procedures. This is the first public introduction of the current developments inherent to the forthcoming ISO 12215-9:2025, which aims to support the design and manufacturing of safe and reliable keel structures for sailing yachts. Furthermore, it is envisaged this work may contribute to the development of future guidelines and regulations for the structural design of hydrofoils and internal supporting structure
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Torpedoes in Parkinson's disease, Alzheimer's disease, essential tremor, and control brains
Purkinje cell axonal swellings ("torpedoes"), described in several cerebellar
disorders as well as essential tremor (ET), have not been quantified in common neurodegenerative
conditions
FXR1 splicing is important for muscle development and biomolecular condensates in muscle cells
© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Smith, J. A., Curry, E. G., Blue, R. E., Roden, C., Dundon, S. E. R., Rodríguez-Vargas, A., Jordan, D. C., Chen, X., Lyons, S. M., Crutchley, J., Anderson, P., Horb, M. E., Gladfelter, A. S., & Giudice, J. FXR1 splicing is important for muscle development and biomolecular condensates in muscle cells. Journal of Cell Biology, 219(4), (2020): e201911129, doi: 10.1083/jcb.201911129.Fragile-X mental retardation autosomal homologue-1 (FXR1) is a muscle-enriched RNA-binding protein. FXR1 depletion is perinatally lethal in mice, Xenopus, and zebrafish; however, the mechanisms driving these phenotypes remain unclear. The FXR1 gene undergoes alternative splicing, producing multiple protein isoforms and mis-splicing has been implicated in disease. Furthermore, mutations that cause frameshifts in muscle-specific isoforms result in congenital multi-minicore myopathy. We observed that FXR1 alternative splicing is pronounced in the serine- and arginine-rich intrinsically disordered domain; these domains are known to promote biomolecular condensation. Here, we show that tissue-specific splicing of fxr1 is required for Xenopus development and alters the disordered domain of FXR1. FXR1 isoforms vary in the formation of RNA-dependent biomolecular condensates in cells and in vitro. This work shows that regulation of tissue-specific splicing can influence FXR1 condensates in muscle development and how mis-splicing promotes disease.We thank the A.S. Gladfelter and J. Giudice laboratories, Nancy Kedersha, and Silvia Ramos for critical discussions; Eunice Y. Lee for technical help; Dr. Stephanie Gupton (University of North Carolina at Chapel Hill, Chapel Hill, NC) for donation of WT C57BL/6J mouse embryos; and Marcin Wlizla and National Xenopus Resource (RRID:SCR_013731) for their help in maintaining adult frogs and other important technical support.
This work has been funded by a University of North Carolina at Chapel Hill Junior Faculty Development Award (to J. Giudice); a Nutrition and Obesity Research Center, University of North Carolina at Chapel Hill, Pilot & Feasibility Research grant (P30DK056350 to J. Giudice); University of North Carolina at Chapel Hill startup funds (to J. Giudice); the March of Dimes Foundation (5-FY18-36, Basil O’Connor Starter Scholar Award to J. Giudice); and NCTraCs Pilot Grant (550KR181805) from the National Center for Advancing Translational Sciences (NCATS), National Institutes of Health, through Grant Award Number UL1TR002489 (to J. Giudice), National Institutes of Health National Institute of General Medical Sciences grants (R01-GM130866 to J. Giudice, R01-GM081506 to A.S. Gladfelter, R35-GM126901 to P. Anderson, K99-GM124458 to S.M. Lyons, R25-GM089569 and 2R25-GM055336-20 to E.G. Curry); Howard Hughes Medical Institute Faculty Scholars program (A.S. Gladfelter), and National Institute of Health grants R01-HD084409 and P40-OD010997 (to M.E. Horb). The content is solely the responsibility of the authors and does not necessarily represent the official views of the funding agencies.2020-09-1
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International meta-analysis of PTSD genome-wide association studies identifies sex- and ancestry-specific genetic risk loci.
The risk of posttraumatic stress disorder (PTSD) following trauma is heritable, but robust common variants have yet to be identified. In a multi-ethnic cohort including over 30,000 PTSD cases and 170,000 controls we conduct a genome-wide association study of PTSD. We demonstrate SNP-based heritability estimates of 5-20%, varying by sex. Three genome-wide significant loci are identified, 2 in European and 1 in African-ancestry analyses. Analyses stratified by sex implicate 3 additional loci in men. Along with other novel genes and non-coding RNAs, a Parkinson's disease gene involved in dopamine regulation, PARK2, is associated with PTSD. Finally, we demonstrate that polygenic risk for PTSD is significantly predictive of re-experiencing symptoms in the Million Veteran Program dataset, although specific loci did not replicate. These results demonstrate the role of genetic variation in the biology of risk for PTSD and highlight the necessity of conducting sex-stratified analyses and expanding GWAS beyond European ancestry populations
Search for charginos in e+e- interactions at sqrt(s) = 189 GeV
An update of the searches for charginos and gravitinos is presented, based on
a data sample corresponding to the 158 pb^{-1} recorded by the DELPHI detector
in 1998, at a centre-of-mass energy of 189 GeV. No evidence for a signal was
found. The lower mass limits are 4-5 GeV/c^2 higher than those obtained at a
centre-of-mass energy of 183 GeV. The (\mu,M_2) MSSM domain excluded by
combining the chargino searches with neutralino searches at the Z resonance
implies a limit on the mass of the lightest neutralino which, for a heavy
sneutrino, is constrained to be above 31.0 GeV/c^2 for tan(beta) \geq 1.Comment: 22 pages, 8 figure
Search for composite and exotic fermions at LEP 2
A search for unstable heavy fermions with the DELPHI detector at LEP is
reported. Sequential and non-canonical leptons, as well as excited leptons and
quarks, are considered. The data analysed correspond to an integrated
luminosity of about 48 pb^{-1} at an e^+e^- centre-of-mass energy of 183 GeV
and about 20 pb^{-1} equally shared between the centre-of-mass energies of 172
GeV and 161 GeV. The search for pair-produced new leptons establishes 95%
confidence level mass limits in the region between 70 GeV/c^2 and 90 GeV/c^2,
depending on the channel. The search for singly produced excited leptons and
quarks establishes upper limits on the ratio of the coupling of the excited
fermio
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