3,189 research outputs found
Small Family with Key Contacts: Par14 and Par17 Parvulin Proteins, Relatives of Pin1, Now Emerge in Biomedical Research
The parvulin-type peptidyl-prolyl cis/trans isomerase Pin1 is subject of intense biochemical and clinical research as it seems to be involved in the pathogenesis of certain cancers and protein folding illnesses like Alzheimerās and Parkinsonās disease. In addition to Pin1, the human genome only contains a single other parvulin locus encoding two protein speciesāPar14 and Par17. Much less is known about these enzymes although their sequences are highly conserved in all metazoans. Parvulin has been proposed to function as Pin1 complementing enzyme in cell cycle regulation and in chromatin remodelling. Pharmaceutical modulation of Par14 might therefore have benefits for certain types of cancer. Moreover, the Par17 protein that has been shown to be confined to anthropoid primate species only might provide a deeper understanding for human-specific brain development. This review aims at stimulating further research on Par14 and Par17 that are overlooked drug targets in the shadow of an overwhelming plethora of Pin1 literature by summarising all current knowledge on these parvulin proteins
Study of Convective Flow Effects in Endwall Casing Treatments in Transonic Compressor Rotors
The unsteady convective flow effects in a transonic compressor rotor with a circumferential-groove casing treatment are investigated in this paper. Experimental results show that the circumferential-groove casing treatment increases the compressor stall margin by almost 50% for the current transonic compressor rotor. Steady flow simulation of the current casing treatment, however, yields only a 15% gain in stall margin. The flow field at near-stall operation is highly unsteady due to several self-induced flow phenomena. These include shock oscillation, vortex shedding at the trailing edge, and interaction between the passage shock and the tip clearance vortex. The primary focus of the current investigation is to assess the effects of flow unsteadiness and unsteady flow convection on the circumferential-groove casing treatment. Unsteady Reynolds-averaged Navier-Stokes (URANS) and Large Eddy Simulation (LES) techniques were applied in addition to steady Reynolds-averaged Navier-Stokes (RANS) to simulate the flow field at near-stall operation and to determine changes in stall margin. The current investigation reveals that unsteady flow effects are as important as steady flow effects on the performance of the circumferential grooves casing treatment in extending the stall margin of the current transonic compressor rotor. The primary unsteady flow mechanism is unsteady flow injection from the grooves into the main flow near the casing. Flows moving into and out of the grooves are caused due to local pressure difference near the grooves. As the pressure field becomes transient due to self-induced flow oscillation, flow injection from the grooves also becomes unsteady. The unsteady flow simulation shows that this unsteady flow injection from the grooves is substantial and contributes significantly to extending the compressor stall margin. Unsteady flows into and out of the grooves have as large a role as steady flows in the circumferential grooves. While the circumferential-groove casing treatment seems to be a steady flow device, unsteady flow effects should be included to accurately assess its performance as the flow is transient at near-stall operation
The public sector construction industry : analysis of single-project partnering
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1993.Vita.Includes bibliographical references (leaves 209-214).by Peter W. Mueller.M.S
Health Worker Compliance with a 'Test And Treat' Malaria Case Management Protocol in Papua New Guinea
The Papua New Guinea (PNG) Department of Health introduced a
'test and treat' malaria case management protocol in 2011. This
study assesses health worker compliance with the test and treat
protocol on a wide range of measures, examines self-reported
barriers to health worker compliance as well as health worker
attitudes towards the test and treat protocol. Data were
collected by cross-sectional survey conducted in randomly
selected primary health care facilities in 2012 and repeated in
2014. The combined survey data included passive observation of
current or recently febrile patients (N = 771) and interviewer
administered questionnaires completed with health workers (N =
265). Across the two surveys, 77.6% of patients were tested for
malaria infection by rapid diagnostic test (RDT) or microscopy,
65.6% of confirmed malaria cases were prescribed the correct
antimalarials and 15.3% of febrile patients who tested negative
for malaria infection were incorrectly prescribed an
antimalarial. Overall compliance with a strictly defined test
and treat protocol was 62.8%. A reluctance to test
current/recently febrile patients for malaria infection by RDT
or microscopy in the absence of acute malaria symptoms,
reserving recommended antimalarials for confirmed malaria cases
only and choosing to clinically diagnose a malaria infection,
despite a negative RDT result were the most frequently reported
barriers to protocol compliance. Attitudinal support for the
test and treat protocol, as assessed by a nine-item measure,
improved across time. In conclusion, health worker compliance
with the full test and treat malaria protocol requires
improvement in PNG and additional health worker support will
likely be required to achieve this. The broader evidence base
would suggest any such support should be delivered over a longer
period of time, be multi-dimensional and multi-modal
Networked differential GPS system
An embodiment of the present invention relates to a worldwide network of differential GPS reference stations (NDGPS) that continually track the entire GPS satellite constellation and provide interpolations of reference station corrections tailored for particular user locations between the reference stations Each reference station takes real-time ionospheric measurements with codeless cross-correlating dual-frequency carrier GPS receivers and computes real-time orbit ephemerides independently. An absolute pseudorange correction (PRC) is defined for each satellite as a function of a particular user's location. A map of the function is constructed, with iso-PRC contours. The network measures the PRCs at a few points, so-called reference stations and constructs an iso-PRC map for each satellite. Corrections are interpolated for each user's site on a subscription basis. The data bandwidths are kept to a minimum by transmitting information that cannot be obtained directly by the user and by updating information by classes and according to how quickly each class of data goes stale given the realities of the GPS system. Sub-decimeter-level kinematic accuracy over a given area is accomplished by establishing a mini-fiducial network
Impaired induction of the Jasmonate Pathway in the rice mutant hebiba
The elongation of rice (Oryza sativa) coleoptiles is inhibited
by light, and this photoinhibition was used to screen for
mutants with impaired light response. In one of the isolated
mutants, hebiba, coleoptile elongation was stimulated in the
presence of red light, but inhibited in the dark. Light
responses of endogenous indolyl-3-acetic acid and abscisic acid
were identical between the wild type and the mutant. In
contrast, the wild type showed a dramatic increase of jasmonate
heralded by corresponding increases in the content of its
precursor o-phytodienoic acid, whereas both compounds were not
detectable in the mutant. The jasmonate response to wounding was
also blocked in the mutant. The mutant phenotype was rescued by
addition of exogenous methyl jasmonate and o-phytodienoic acid.
Moreover, the expression of O. sativa 12-oxophytodienoic acid
reductase, an early gene of jasmonic acid-synthesis, is induced
by red light in the wild type, but not in the mutant. This
evidence suggests a novel role for jasmonates in the light
response of growth, and we discuss a cross-talk between
jasmonate and auxin signaling. In addition, hebiba represents
the first rice mutant in which the induction of the jasmonate
pathway is impaired providing a valuable tool to study the role
of jasmonates in Graminean development
Brewster-angle measurements of sea-surface reflectance using a high resolution spectroradiometer
This paper describes the design, construction and testing of a ship-borne spectroradiometer based on an imaging spectrograph and cooled CCD array with a wavelength range of 350-800 nm and 4 nm spectral sampling. The instrument had a minimum spectral acquisition time of 0.1 s, but in practice data were collected over periods of 10 s to allow averaging of wave effects. It was mounted on a ship's superstructure so that it viewed the sea surface from a height of several metres at the Brewster angle (53 degrees) through a linear polarizing filter. Comparison of sea-leaving spectra acquired with the polarizer oriented horizontally and vertically enabled estimation of the spectral composition of sky light reflected directly from the sea surface. A semi-empirical correction procedure was devised for retrieving water-leaving radiance spectra from these measurements while minimizing the influence of reflected sky light. Sea trials indicated that reflectance spectra obtained by this method were consistent with the results of radiance transfer modelling of case 2 waters with similar concentrations of chlorophyll and coloured dissolved organic matter. Surface reflectance signatures measured at three locations containing blooms of different phytoplankton species were easily discriminated and the instrument was sufficiently sensitive to detect solar-stimulated fluorescence from surface chlorophyll concentrations down to 1 mg mā3
- ā¦