317 research outputs found
Ab initio calculation of the CdSe/CdTe heterojunction band offset using the local-density approximation-1/2 technique with spin-orbit corrections
We performed ab initio calculations of the electronic structures of bulk CdSe and CdTe and of their interface. We employed the local-density approximation-1/2 self-energy correction scheme [L. G. Ferreira, M. Marques, and L. K. Teles, Phys. Rev. B 78, 125116 (2008)] to obtain improved band gaps and band offsets, as well as spin-orbit coupling to further correct the valence band edges. Our results are in good agreement with experimental values for bulk band gaps and reproduce the staggered band alignment characteristic of this system. We found that the spin-orbit effect is of considerable importance for the bulk band gaps, but has little impact on the band offset of this particular system. Moreover, the electronic structure calculated along the 61.4 Å transition region across the CdSe/CdTe interface shows a non-monotonic variation of the bandgap in the range 0.8-1.8 eV. This finding may have important implications to the absorption of light along the interface between these two materials in photovoltaic applications1117FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2006/05858-
Post-operative management of inflammation after orthopaedic surgeries using trypsin, bromelain and rutoside combination: a single-centre prospective observational study
Background: Post-operative management of inflammation plays an important role in orthopaedic surgeries, as delay in wound healing may lead to extended hospital stay. Proteases like trypsin and bromelain combined with the bioflavonoid rutoside are often used to reduce post-operative pain and swelling. The present study aimed to evaluate the efficacy and safety of oral administration of a fixed dose combination of trypsin-bromelain-rutoside in the post-operative management after orthopaedic surgeries.Methods: The study was a prospective, observational data collection exercise. Hundred subjects undergoing orthopaedic surgeries, who were administered trypsin-bromelain-rutoside combination, were observed over a period of 8 days post-surgery. Verbal rating scales were used for grading the pain intensity and extent of swelling, while a 5-point Likert scale was used to evaluate patient- and investigator-reported global assessment of improvement in pain and swelling. Scores at day 3 and day 8 were analysed using paired t test.Results: At day 3 and day 8, the mean scores of pain and swelling were significantly reduced from baseline (all p<0.0001). By day 8, 74% of the patients achieved complete resolution of pain, while 50% reported complete resolution of swelling. By day 8, 54% patients reported excellent/ very good global improvement in pain and swelling, while the investigator reported excellent/ very good global improvement in 81% of the patients. No adverse event was reported in any of the patients.Conclusions: The combination of trypsin-bromelain-rutoside was safe and effective in reducing the post-operative pain and swelling after orthopaedic surgeries. An 8-day treatment led to complete resolution of pain in three-fourths of the patients and complete resolution of swelling in half the patients. The use of this combination has the potential to reduce hospital stay and pill burden
Detailed Bathymetric Surveys in the Central Indian Basin
Over 420,000 line kilometers of echo-sounding data was collected in the Central Indian Basin. This data was digitized, merged with navigation data and a detailed bathymetric map of the Basin was prepared. The Basin can be broadly classified into three regions as high relief area, medium relief area and plain area represented by western, eastern and central portions of the Basin, respectively. The bathymetric map prepared from this survey is the first of its kind for this region and will in the future be used as a base by navigators and researchers
Segmentation and tracking of mesoscale eddies in numeric ocean models
An adequate understanding of climate variability and the eventual prediction of climate change are among the most urgent and far-reaching efforts of the scientific community.. Measurements done to-date have suggested that the mesoscale eddies and mesoscale features play a strong role in carrying heat poleward. Oceanographic visualizations may play a key role in unraveling these mysteries. In this paper we propose techniques for the automated detection, segmentation and tracking of these eddies. A structuring element based on velocity data is designed to detect centers of eddies. Best fitting ellipses/circular donuts are determined to outline and segment out the region of swirling currents around the detected centers. Segmented images from consecutive days of data are used to track eddies temporally. Small-motion assumption is used to track the full trajectory of the eddies. Visualizations resulting from this project will provide oceanographers an invaluable tool to assess mesoscale eddies and the Lagrangian characteristics of this mesoscale oceanic feature. 1
High-Angular Resolution Dust Polarization Measurements: Shaped B-field Lines in the Massive Star Forming Region Orion BN/KL
We present observational results of the thermal dust continuum emission and
its linear polarization in one of the nearest massive star-forming sites Orion
BN/KL in Orion Molecular Cloud-1. The observations were carried out with the
Submillimeter Array. With an angular resolution of 1" (~2 mpc; 480 AU), we have
detected and resolved the densest cores near the BN/KL region. At a wavelength
of ~870 micron, the polarized dust emission can be used to trace the structure
of the magnetic field in this star-forming core. The dust continuum appears to
arise from a V-shaped region, with a cavity nearly coincident with the center
of the explosive outflows observed on larger scales. The position angles
(P.A.s) of the observed polarization vary significantly by a total of about 90
degree but smoothly, i.e., curl-like, across the dust ridges. Such a
polarization pattern can be explained with dust grains being magnetically
aligned instead of mechanically with outflows, since the latter mechanism would
cause the P.A.s to be parallel to the direction of the outflow, i.e.,
radial-like. The magnetic field projected in the plane of sky is therefore
derived by rotating the P.A.s of the polarization by 90 degree. We find an
azimuthally symmetric structure in the overall magnetic field morphology, with
the field directions pointing toward 2.5" west to the center of the explosive
outflows. We also find a preferred symmetry plane at a P.A. of 36 degree, which
is perpendicular to the mean magnetic field direction (120 degree) of the 0.5
pc dust ridge. Two possible interpretations of the origin of the observed
magnetic field structure are discussed.Comment: 27 pages, 7 figures; ApJ in pres
Magnetic Fields and Massive Star Formation
Massive stars ( \msun) typically form in parsec-scale molecular clumps
that collapse and fragment, leading to the birth of a cluster of stellar
objects. We investigate the role of magnetic fields in this process through
dust polarization at 870 m obtained with the Submillimeter Array (SMA).
The SMA observations reveal polarization at scales of \lsim 0.1 pc. The
polarization pattern in these objects ranges from ordered hour-glass
configurations to more chaotic distributions. By comparing the SMA data with
the single dish data at parsec scales, we found that magnetic fields at dense
core scales are either aligned within of or perpendicular to the
parsec-scale magnetic fields. This finding indicates that magnetic fields play
an important role during the collapse and fragmentation of massive molecular
clumps and the formation of dense cores. We further compare magnetic fields in
dense cores with the major axis of molecular outflows. Despite a limited number
of outflows, we found that the outflow axis appears to be randomly oriented
with respect to the magnetic field in the core. This result suggests that at
the scale of accretion disks (\lsim 10^3 AU), angular momentum and dynamic
interactions possibly due to close binary or multiple systems dominate over
magnetic fields. With this unprecedentedly large sample massive clumps, we
argue on a statistical basis that magnetic fields play an important role during
the formation of dense cores at spatial scale of 0.01 - 0.1 pc in the context
of massive star and cluster star formation.Comment: Accepted for publication in Astrophysical Journa
Local Magnetic Field Role in Star Formation
We highlight distinct and systematic observational features of magnetic field
morphologies in polarized submm dust continuum. We illustrate this with
specific examples and show statistical trends from a sample of 50 star-forming
regions.Comment: 4 pages, 3 figures; to appear in the EAS Proceedings of the 6th
Zermatt ISM Symposium "Conditions and Impact of Star Formation from Lab to
Space", September 201
Chemical Cross-Linking of Corneal Tissue to Reduce Progression of Loss of Sight in Patients With Keratoconus
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