35,353 research outputs found
Noncommutative D-Brane in Non-Constant NS-NS B Field Background
We show that when the field strength H of the NS-NS B field does not vanish,
the coordinates X and momenta P of an open string endpoints satisfy a set of
mixed commutation relations among themselves. Identifying X and P with the
coordinates and derivatives of the D-brane world volume, we find a new type of
noncommutative spaces which is very different from those associated with a
constant B field background.Comment: 11 pages, Latex, minor modification
Retrospective study of more than 9000 feline cutaneous tumours in the UK: 2006–2013
The aim of the study was to utilise a large database available from a UK-based, commercial veterinary diagnostic laboratory to ascertain the prevalence of different forms of cutaneous neoplasia within the feline population, and to detect any breed, sex or age predilections for the more common tumours
A UV completion of scalar electrodynamics
In previous works, we constructed UV-finite and unitary scalar field theories
with an infinite spectrum of propagating modes for arbitrary polynomial
interactions. In this paper, we introduce infinitely many massive vector fields
into a U(1) gauge theory to construct a theory with UV-finiteness and
unitarity.Comment: 25 page
Impact of OKT3 therapy on cytomegalovirus and herpes simplex virus infections after liver transplantation
The purpose of this study was to analyze the impact of OKT3 on the frequency and severity of CMV and herpes simplex virus (HSV) infections in adult liver transplant recipients. OKT3 treatment is associated with a higher risk of disseminated CMV infection, particularly in patients with primary CMV infection. It also increased the frequency of symptomatic HSV infection in HSV-seropositive liver transplant recipients
Flexible parylene actuator for micro adaptive flow control
This paper describes the first flexible parylene electrostatic actuator valves intended for micro adaptive flow control for the future use on the wings of micro-air-vehicle (MAV). The actuator diaphragm is made of two layers of parylene membranes with offset vent holes. Without electrostatic actuation, air can move freely from one side of the skin to the other side through the vent holes. With actuation, these vent holes are sealed and the airflow is controlled. The membrane behaves as a complete diaphragm.
We have successfully demonstrated this function using a 2-mm x 2-mm parylene diaphragm electrostatic actuator valves. This work also includes the novel anti-stiction technology that is crucial to make such large-area parylene actuator diaphragm with the combined use of anti-stiction posts, self-assembled monolayers (SAM), surface roughening, and bromine trifluoride (BrFe) dry etching. With the help of SAM treatment, the operating voltage is lowered from 30 volts to 13 volts. The load deflection method is then used to measure the effective thickness of the composite
diaphragm. The flexible parylene diaphragm can be deflected up to 100 μm when 150 Torr of pressure is applied. The result is fitted into a theoretical model and yields an effective thickness of 5.9 μm, which is agreeable with the actual thickness of 5.6 μm, thus proves the functionality of the device
Chiral magnetic wave at finite baryon density and the electric quadrupole moment of quark-gluon plasma in heavy ion collisions
Chiral Magnetic Wave (CMW) is a gapless collective excitation of quark-gluon
plasma in the presence of external magnetic field that stems from the interplay
of Chiral Magnetic (CME) and Chiral Separation Effects (CSE); it is composed by
the waves of the electric and chiral charge densities coupled by the axial
anomaly. We consider CMW at finite baryon density and find that it induces the
electric quadrupole moment of the quark-gluon plasma produced in heavy ion
collisions: the "poles" of the produced fireball (pointing outside of the
reaction plane) acquire additional positive electric charge, and the "equator"
acquires additional negative charge. We point out that this electric quadrupole
deformation lifts the degeneracy between the elliptic flows of positive and
negative pions leading to , and estimate the magnitude
of the effect.Comment: 4 pages, 3 figure
BPS States on M5-brane in Large C-field Background
We extensively study BPS solutions of the low energy effective theory of
M5-brane in large C-field background. This provides us an opportunity to
explore the interactions turned on by C-field background through the
Nambu-Poisson structure. The BPS states considered in this paper include the
M-waves, the self-dual string (M2 ending on M5), tilted M5-brane, holomorphic
embedding of M5-brane and the intersection of two M5-branes along a 3-brane.Comment: 25 pages, reference adde
Thermal stability of titanium nitride for shallow junction solar cell contacts
To demonstrate the thermal stability of titanium nitride as a high-temperature diffusion barrier, the TiN-Ti-Ag metallization scheme has been tested on shallow-junction (~2000 Å) Si solar cells. Electrical measurements on reference samples with the Ti-Ag metallization scheme show serious degradation after a 600 °C, 10-min annealing. With the TiN-Ti-Ag scheme, no degradation of cell performance is observed after the same heat treatment if the TiN layer is >~1700 Å. The glass encapsulation of cells by electrostatic bonding requires such a heat treatment
The enigmatic spin evolution of PSR J0537-6910: r-modes, gravitational waves and the case for continued timing
We discuss the unique spin evolution of the young X-ray pulsar PSR
J0537-6910, a system in which the regular spin down is interrupted by glitches
every few months. Drawing on the complete timing data from the Rossi X-ray
Timing Explorer (RXTE, from 1999-2011), we argue that a trend in the
inter-glitch behaviour points to an effective braking index close to ,
much larger than expected. This value is interesting because it would accord
with the neutron star spinning down due to gravitational waves from an unstable
r-mode. We discuss to what extent this, admittedly speculative, scenario may be
consistent and if the associated gravitational-wave signal would be within
reach of ground based detectors. Our estimates suggest that one may, indeed, be
able to use future observations to test the idea. Further precision timing
would help enhance the achievable sensitivity and we advocate a joint observing
campaign between the Neutron Star Interior Composition ExploreR (NICER) and the
LIGO-Virgo network.Comment: 10 pages, 4 figures, emulate ApJ forma
Fungal infections after liver transplantation
The risk factors for development of invasive fungal infections after liver transplantation were (1) longer duration of treatment with nonprophylactic IV antibiotics, (2) longer cumulative surgical time and a higher number of laparotomies, (3) an increased number of units of RBCs and fresh-frozen plasma, and (4) a series of pretransplant laboratory findings: thrombocytopenia, low T lymphocyte levels, low CD4 helper cell and lower helper/suppressor cell ratios and IgA serum levels. The significance of some of these findings is still unclear. Attention to the risk factors outlined earlier may aid both in preventing and in the early detection of invasive fungal infections after liver transplantation
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