1,740 research outputs found
An Unusually Large Submandibular Gland Stone. A Case Report.
A Case of 65 year old man that presented with 40 years history of right lower jaw swelling, that became associated with pain two weeks prior to presentation. Examination revealed an elderly man with an enlarged tender right submandibular gland. The medial margin was suppurating. X-ray of the right lower jaw revealed large stone, while ultrasound scan of the right submandibular region revealed an associated abscess. The latter was incised and drained, while excision of the right submandibular gland and calculus was carried out three weeks later. 5.0cm - sized stone was excised. This turned out to be the second largest salivary gland stone recorded in literature. Conclusion Giant salivary gland stone which ( greater than 1.5cm) is rare. To the best of our knowledge, our index patient with a calculus measuring 5.0 x 3.0cm is the second largest stone in literature is remarkable KeyWords: Giant Salivary Gland Stone, Submandibular Glan
Au/n-ZnO rectifying contact fabricated with hydrogen peroxide pretreatment
Au contacts were deposited on n -type ZnO single crystals with and without hydrogen peroxide pretreatment for the ZnO substrate. The Au/ZnO contacts fabricated on substrates without H2 O2 pretreatment were Ohmic and those with H2 O2 pretreatment were rectifying. With an aim of fabricating a good quality Schottky contact, the rectifying property of the Au/ZnO contact was systemically investigated by varying the treatment temperature and duration. The best performing Schottky contact was found to have an ideality factor of 1.15 and a leakage current of ∼ 10-7 A cm-2. A multispectroscopic study, including scanning electron microscopy, positron annihilation spectroscopy, deep level transient spectroscopy, x-ray photoelectron spectroscopy, and photoluminescence, showed that the H2 O2 treatment removed the OH impurity and created Zn-vacancy related defects hence decreasing the conductivity of the ZnO surface layer, a condition favorable for forming good Schottky contact. However, the H2 O2 treatment also resulted in a deterioration of the surface morphology, leading to an increase in the Schottky contact ideality factor and leakage current in the case of nonoptimal treatment time and temperature. © 2008 American Institute of Physics.published_or_final_versio
Hydrogen peroxide treatment induced rectifying behavior of Aun-ZnO contact
Conversion of the Aun-ZnO contact from Ohmic to rectifying with H2 O2 pretreatment was studied systematically using I-V measurements, x-ray photoemission spectroscopy, positron annihilation spectroscopy, and deep level transient spectroscopy. H2 O2 treatment did not affect the carbon surface contamination or the EC -0.31 eV deep level, but it resulted in a significant decrease of the surface OH contamination and the formation of vacancy-type defects (Zn vacancy or vacancy cluster) close to the surface. The formation of a rectifying contact can be attributed to the reduced conductivity of the surface region due to the removal of OH and the formation of vacancy-type defects. © 2007 American Institute of Physics.published_or_final_versio
Consumption of cocoa flavanols results in acute improvements in mood and cognitive performance during sustained mental effort
Cocoa flavanols (CF) positively influence physiological processes in ways that suggest their consumption may improve aspects of cognitive function. This study investigated the acute cognitive and subjective effects of CF consumption during sustained mental demand. In this randomized, controlled, double-blinded, balanced, three period crossover trial 30 healthy adults consumed drinks containing 520 mg, 994 mg CF and a matched control, with a three-day washout between drinks. Assessments included the state anxiety inventory and repeated 10-min cycles of a Cognitive Demand Battery comprising of two serial subtraction tasks (Serial Threes and Serial Sevens), a Rapid Visual Information Processing (RVIP) task and a mental fatigue scale, over the course of 1 h. Consumption of both 520 mg and 994 mg CF significantly improved Serial Threes performance. The 994 mg CF beverage significantly speeded RVIP responses but also resulted in more errors during Serial Sevens. Increases in self-reported mental fatigue were significantly attenuated by the consumption of the 520 mg CF beverage only. This is the first report of acute cognitive improvements following CF consumption in healthy adults. While the mechanisms underlying the effects are unknown they may be related to known effects of CF on endothelial function and blood flow
Extremely long quasiparticle spin lifetimes in superconducting aluminium using MgO tunnel spin injectors
There has been an intense search in recent years for long-lived
spin-polarized carriers for spintronic and quantum-computing devices. Here we
report that spin polarized quasi-particles in superconducting aluminum layers
have surprisingly long spin-lifetimes, nearly a million times longer than in
their normal state. The lifetime is determined from the suppression of the
aluminum's superconductivity resulting from the accumulation of spin polarized
carriers in the aluminum layer using tunnel spin injectors. A Hanle effect,
observed in the presence of small in-plane orthogonal fields, is shown to be
quantitatively consistent with the presence of long-lived spin polarized
quasi-particles. Our experiments show that the superconducting state can be
significantly modified by small electric currents, much smaller than the
critical current, which is potentially useful for devices involving
superconducting qubits
Cold Gas in Massive Galaxies as a Critical Test of Black Hole Feedback Models
Black hole feedback has been widely implemented as the key recipe to quench
star formation in massive galaxies in modern semi-analytic models and
hydrodynamical simulations. As the theoretical details surrounding the
accretion and feedback of black holes continue to be refined, various feedback
models have been implemented across simulations, with notable differences in
their outcomes. Yet, most of these simulations have successfully reproduced
some observations, such as stellar mass function and star formation rate
density in the local Universe. We use the recent observation on the change of
neutral hydrogen gas mass (including both and ) with star
formation rate of massive central disc galaxies as a critical constraint of
black hole feedback models across several simulations. We find that the
predictions of IllustrisTNG agree with the observations much better than the
other models tested in this work. This favors IllustrisTNG's treatment of
active galactic nuclei - where kinetic winds are driven by black holes at low
accretion rates - as more plausible amongst those we test. In turn, this also
indirectly supports the idea that the massive central disc galaxy population in
the local Universe was likely quenched by AGN feedback
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Cold Gas in Massive Galaxies as a Critical Test of Black Hole Feedback Models
Black hole feedback has been widely implemented as the key recipe to quench
star formation in massive galaxies in modern semi-analytic models and
hydrodynamical simulations. As the theoretical details surrounding the
accretion and feedback of black holes continue to be refined, various feedback
models have been implemented across simulations, with notable differences in
their outcomes. Yet, most of these simulations have successfully reproduced
some observations, such as stellar mass function and star formation rate
density in the local Universe. We use the recent observation on the change of
neutral hydrogen gas mass (including both and ) with star
formation rate of massive central disc galaxies as a critical constraint of
black hole feedback models across several simulations. We find that the
predictions of IllustrisTNG agree with the observations much better than the
other models tested in this work. This favors IllustrisTNG's treatment of
active galactic nuclei - where kinetic winds are driven by black holes at low
accretion rates - as more plausible amongst those we test. In turn, this also
indirectly supports the idea that the massive central disc galaxy population in
the local Universe was likely quenched by AGN feedback
Novel Binding Mode of a Potent and Selective Tankyrase Inhibitor
Tankyrases (TNKS1 and TNKS2) are key regulators of cellular processes such as telomere pathway and Wnt signaling. IWRs (inhibitors of Wnt response) have recently been identified as potent and selective inhibitors of tankyrases. However, it is not clear how these IWRs interact with tankyrases. Here we report the crystal structure of the catalytic domain of human TNKS1 in complex with IWR2, which reveals a novel binding site for tankyrase inhibitors. The TNKS1/IWR2 complex provides a molecular basis for their strong and specific interactions and suggests clues for further development of tankyrase inhibitors
Resonances in and
A partial wave analysis is presented of and
from a sample of 58M events in the BES II detector. The
is observed clearly in both sets of data, and parameters of the
Flatt\' e formula are determined accurately: (stat)
(syst) MeV/c, MeV/c, . The data also exhibit a strong peak
centred at MeV/c. It may be fitted with and a
dominant signal made from interfering with a smaller
component. There is evidence that the signal is
resonant, from interference with . There is also a state in with MeV/c and
MeV/c; spin 0 is preferred over spin 2. This state, , is
distinct from . The data contain a strong peak due to
. A shoulder on its upper side may be fitted by interference
between and .Comment: 17 pages, 6 figures, 1 table. Submitted to Phys. Lett.
Measurement of the Branching Fraction of J/psi --> pi+ pi- pi0
Using 58 million J/psi and 14 million psi' decays obtained by the BESII
experiment, the branching fraction of J/psi --> pi+ pi- pi0 is determined. The
result is (2.10+/-0.12)X10^{-2}, which is significantly higher than previous
measurements.Comment: 9 pages, 8 figures, RevTex
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