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The Function and Regulation of Sleep in Drosophila melanogaster
A key feature of sleep is reduced responsiveness to the environment, which puts animals in a particularly vulnerable state; yet, sleep has been conserved throughout evolution, indicating that it fulfills a vital purpose. A core function of sleep across species has not been identified, but substantial advances in sleep research have been made in recent years using the genetically tractable model organism, Drosophila melanogaster. While a standard approach in sleep research is to study the effects of short-term sleep deprivation on an animal, tools are now available to genetically manipulate sleep amount in the fruit fly. In particular, a number of short-sleeping Drosophila mutants have been identified that model the long-term sleep restriction that is widespread in modern society. This thesis describes a body of work in which short-sleeping Drosophila mutants, as well as other genetic and pharmacological tools, were used to shed light on the function and regulation of sleep
Analysis of Photogrammetry Data from ISIM Mockup, June 1, 2007
During ground testing of the Integrated Science Instrument Module (ISIM) for the James Webb Space Telescope (JWST), the ISIM Optics group plans to use a Photogrammetry Measurement System for cryogenic calibration of specific target points on the ISIM composite structure and Science Instrument optical benches and other GSE equipment. This testing will occur in the Space Environmental Systems (SES) chamber at Goddard Space Flight Center. Close range photogrammetry is a 3 dimensional metrology system using triangulation to locate custom targets in 3 coordinates via a collection of digital photographs taken from various locations and orientations. These photos are connected using coded targets, special targets that are recognized by the software and can thus correlate the images to provide a 3 dimensional map of the targets, and scaled via well calibrated scale bars. Photogrammetry solves for the camera location and coordinates of the targets simultaneously through the bundling procedure contained in the V-STARS software
The prion protein constitutively controls neuronal store-operated ca2+ entry through Fyn Kinase
The prion protein (PrPC) is a cell surface glycoprotein mainly expressed in neurons, whose misfolded isoforms generate the prion responsible for incurable neurodegenerative disorders. Whereas PrPC involvement in prion propagation is well established, PrPC physiological function is still enigmatic despite suggestions that it could act in cell signal transduction by modulating phosphorylation cascades and Ca2+ homeostasis. Because PrPC binds neurotoxic protein aggregates with high-affinity, it has also been proposed that PrPC acts as receptor for amyloid-\u3b2 (A\u3b2) oligomers associated with Alzheimer\u2019s disease (AD), and that PrPC-A\u3b2 binding mediates AD-related synaptic dysfunctions following activation of the tyrosine kinase Fyn. Here, use of gene-encoded Ca2+ probes targeting different cell domains in primary cerebellar granule neurons (CGN) expressing, or not, PrPC, allowed us to investigate whether PrPC regulates store-operated Ca2+ entry (SOCE) and the implication of Fyn in this control. Our findings show that PrPC attenuates SOCE, and Ca2+ accumulation in the cytosol and mitochondria, by constitutively restraining Fyn activation and tyrosine phosphorylation of STIM1, a key molecular component of SOCE. This data establishes the existence of a PrPC-Fyn-SOCE triad in neurons. We also demonstrate that treating cerebellar granule and cortical neurons with soluble A\u3b2(1\u201342) oligomers abrogates the control of PrPC over Fyn and SOCE, suggesting a PrPC-dependent mechanizm for A\u3b2-induced neuronal Ca2+ dyshomeostasis
Analysis of Photogrammetry Data from ISIM Mockup
During ground testing of the Integrated Science Instrument Module (ISIM) for the James Webb Space Telescope (JWST), the ISIM Optics group plans to use a Photogrammetry Measurement System for cryogenic calibration of specific target points on the ISIM composite structure and Science Instrument optical benches and other GSE equipment. This testing will occur in the Space Environmental Systems (SES) chamber at Goddard Space Flight Center. Close range photogrammetry is a 3 dimensional metrology system using triangulation to locate custom targets in 3 coordinates via a collection of digital photographs taken from various locations and orientations. These photos are connected using coded targets, special targets that are recognized by the software and can thus correlate the images to provide a 3 dimensional map of the targets, and scaled via well calibrated scale bars. Photogrammetry solves for the camera location and coordinates of the targets simultaneously through the bundling procedure contained in the V-STARS software, proprietary software owned by Geodetic Systems Inc. The primary objectives of the metrology performed on the ISIM mock-up were (1) to quantify the accuracy of the INCA3 photogrammetry camera on a representative full scale version of the ISIM structure at ambient temperature by comparing the measurements obtained with this camera to measurements using the Leica laser tracker system and (2), empirically determine the smallest increment of target position movement that can be resolved by the PG camera in the test setup, i.e., precision, or resolution. In addition, the geometrical details of the test setup defined during the mockup testing, such as target locations and camera positions, will contribute to the final design of the photogrammetry system to be used on the ISIM Flight Structure
Residential development proposal for a site in Brighton, Massachusetts
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, and Dept. of Urban Studies and Planning, 1986.MICROFICHE COPY AVAILABLE IN ARCHIVES AN ROTCH.Bibliography: leaves 83-84.by Andrew W. Gutowski and Maria D. Hill.M.S
Methodological Considerations for Comparison of Cross-species Use of Tactile Contact
Cross-species comparisons are benefited by compatible datasets; conclusions related to phylogenetic comparisons, questions on convergent and divergent evolution, or homologs versus analogs can only be made when the behaviors being measured are comparable. A direct comparison of the social function of physical contact across two disparate taxa is possible only if data collection and analyses methodologies are analogous. We identify and discuss the parameters, assumptions and measurement schemes applicable to multiple taxa and species that facilitate cross-species comparisons. To illustrate our proposed guidelines for evaluating the role played by tactile contact in social behavior across disparate taxa, this paper presents data on mother-offspring relationships in the two species studied by the authors: chimpanzees (Pan troglodytes schweinfurthii) and dolphins (bottlenose and spotted, Tursiops truncatus and Stenella frontalis, respectively). Cross-species comparative studies allow for a more comprehensive assessment of the similarities and differences with respect to how animals traverse the relationships that form their social groups and societies
The National Singing Programme for primary schools in England: an initial baseline study
The âSing Upâ National Singing Programme for Primary schools in England was launched in November 2007 under the UK Governmentâs âMusic Manifestoâ. âSing Upâ is a four-year programme whose overall aim is to raise the status of singing and increase opportunities for children throughout the country to enjoy singing as part of their everyday lives, in and out of school. As part of the Programmeâs research evaluation, a key focus has been to build an initial picture of singing in Primary schools across England. This information could then be used as a âbaselineâ by which the programmeâs subsequent impact could be judged, including âbeforeâ and âafterâ measures of schools that receive particular âSing Upâ input. This paper reports an overview of key outcomes of first five months of baseline profiling (October, 2007 to February 2008), embracing analyses of the singing behaviours of 3,472 children in 76 Primary schools. These findings are complimented by additional analyses of childrenâs views on singing in and out of school; and the self-efficacy of their class teachersâ (n=90), both as singers and as teachers of singing
Astronomical verification of a stabilized frequency reference transfer system for the Square Kilometre Array
In order to meet its cutting-edge scientific objectives, the Square Kilometre
Array (SKA) telescope requires high-precision frequency references to be
distributed to each of its antennas. The frequency references are distributed
via fiber-optic links and must be actively stabilized to compensate for
phase-noise imposed on the signals by environmental perturbations on the links.
SKA engineering requirements demand that any proposed frequency reference
distribution system be proved in "astronomical verification" tests. We present
results of the astronomical verification of a stabilized frequency reference
transfer system proposed for SKA-mid. The dual-receiver architecture of the
Australia Telescope Compact Array was exploited to subtract the phase-noise of
the sky signal from the data, allowing the phase-noise of observations
performed using a standard frequency reference, as well as the stabilized
frequency reference transfer system transmitting over 77 km of fiber-optic
cable, to be directly compared. Results are presented for the fractional
frequency stability and phase-drift of the stabilized frequency reference
transfer system for celestial calibrator observations at 5 GHz and 25 GHz.
These observations plus additional laboratory results for the transferred
signal stability over a 166 km metropolitan fiber-optic link are used to show
that the stabilized transfer system under test exceeds all SKA phase-stability
requirements under a broad range of observing conditions. Furthermore, we have
shown that alternative reference dissemination systems that use multiple
synthesizers to supply reference signals to sub-sections of an array may limit
the imaging capability of the telescope.Comment: 12 pages, accepted to The Astronomical Journa
Alterations in oxidative, inflammatory and apoptotic events in short-lived and long-lived mice testes
Aged testes undergo profound histological and morphological alterations leading to a reduced functionality. Here, we investigated whether variations in longevity affect the development of local inflammatory processes, the oxidative state and the occurrence of apoptotic events in the testis. To this aim, well-established mouse models with delayed (growth hormone releasing hormone-knockout and Ames dwarf mice) or accelerated (growth hormone-transgenic mice) aging were used. We hereby show that the testes of short-lived mice show a significant increase in cyclooxygenase 2 expression, PGD2 production, lipid peroxidation, antioxidant enzymes expression, local macrophages and TUNEL-positive germ cells numbers, and the levels of both pro-caspase-3 and cleaved caspase-3. In contrast, although the expression of antioxidant enzymes remained unchanged in testes of long-lived mice, the remainder of the parameters assessed showed a significant reduction. This study provides novel evidence that longevity confers anti-inflammatory, anti-oxidant and anti-apoptotic capacities to the adult testis. Oppositely, short-lived mice suffer testicular inflammatory, oxidative and apoptotic processes.Fil: Matzkin, Maria Eugenia. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Instituto de BiologĂa y Medicina Experimental. FundaciĂłn de Instituto de BiologĂa y Medicina Experimental. Instituto de BiologĂa y Medicina Experimental; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Departamento de BioquĂmica Humana; ArgentinaFil: Miquet, Johanna Gabriela. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica; ArgentinaFil: Fang, Yimin. Southern Illinois University. School Of Medicine; Estados UnidosFil: Hill, Cristal Monique. Southern Illinois University; Estados UnidosFil: Turyn, Daniel. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de QuĂmica y FĂsico-QuĂmica BiolĂłgicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica. Instituto de QuĂmica y FĂsico-QuĂmica BiolĂłgicas; ArgentinaFil: Calandra, Ricardo Saul. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Instituto de BiologĂa y Medicina Experimental. FundaciĂłn de Instituto de BiologĂa y Medicina Experimental. Instituto de BiologĂa y Medicina Experimental; ArgentinaFil: Bartke, Andrzej. Southern Illinois University; Estados UnidosFil: Frungieri, Monica Beatriz. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Instituto de BiologĂa y Medicina Experimental. FundaciĂłn de Instituto de BiologĂa y Medicina Experimental. Instituto de BiologĂa y Medicina Experimental; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Departamento de BioquĂmica Humana; Argentin
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