251 research outputs found
Landau Ghosts and Anti-Ghosts in Condensed Matter and High Density Hadronic Matter
It is observed that the ``ghost'' (originally discovered by Landau in quantum
electro-dynamics) and its counterparts in other theories are indeed ubiquitous
as they occur in a one-loop approximation to any conventional (unbroken) gauge
theory. The mechanism is first exposed in its generality via the Dyson equation
and a simple but explicit example in condensed matter is provided through the
static Clausius-Mossotti and its dynamic counterpart the Lorenz-Lorentz
equation. The physical phase transition phenomenon associated with it is found
to be super-radiance. We verify quantitatively that water (and many other polar
liquids) are indeed super-radiant at room temperature. In quantum
chromo-dynamics on the other hand, we encounter, thanks to asymptotic freedom,
an ``anti-ghost'' which is closely associated with color confinement. Thus, in
QCD, free quarks and glue exist in a super-radiant phase and hadronic matter in
the normal one.Comment: LaTeX 12 Pages and 2 *.eps Figure
Floating Active Baffles, System and Method of Slosh Damping Comprising the Same
This disclosure provides a system for damping slosh of a liquid within a tank, a baffle for use in the system, and a method of damping slosh using the system. The system includes a plurality of baffles. Each baffle has a body configured to substantially float upon the liquid. Each baffle also has an activation material received along at least a portion of the body. The activation material is magnetically reactive provided in a quantity sufficient to enable the body to be manipulated in the presence of a magnetic field (M). The system further includes an actuator configured to proÂvide the magnetic field (M)
Resonance Damping in Ferromagnets and Ferroelectrics
The phenomenological equations of motion for the relaxation of ordered phases
of magnetized and polarized crystal phases can be developed in close analogy
with one another. For the case of magnetized systems, the driving magnetic
field intensity toward relaxation was developed by Gilbert. For the case of
polarized systems, the driving electric field intensity toward relaxation was
developed by Khalatnikov. The transport times for relaxation into thermal
equilibrium can be attributed to viscous sound wave damping via
magnetostriction for the magnetic case and electrostriction for the
polarization case.Comment: 5 pages no figures ReVTeX
Thermal Time Scales in a Color Glass Condensate
In a model of relativistic heavy ion collisions wherein the unconfined
quark-gluon plasma is condensed into glass, we derive the Vogel-Fulcher-Tammann
cooling law. This law is well known to hold true in condensed matter glasses.
The high energy plasma is initially created in a very hot negative temperature
state and cools down to the Hagedorn glass temperature at an ever decreasing
rate. The cooling rate is largely determined by the QCD string tension derived
from hadronic Regge trajectories. The ultimately slow relaxation time is a
defining characteristic of a color glass condensate.Comment: 5 pages, ReVTeX format, nofigure
Theory of the Maxwell Pressure Tensor and the Tension in a Water Bridge
A water bridge refers to an experimental "flexible cable" made up of pure
deionized water which can hang across two supports maintained with a
sufficiently large voltage difference. The resulting electric fields within the
deionized water flexible cable, maintain a tension which sustains the water
against the downward force of gravity. A detailed calculation of the water
bridge tension will be provided in terms of the Maxwell pressure tensor in a
dielectric fluid medium. General properties of the dielectric liquid pressure
tensor are discussed along with unusual features of dielectric fluid Bernoulli
flows in an electric field. Analogies between dielectric fluid Bernoulli flows
in strong electric fields and quantum Bernoulli flows in superfluids are
explored.Comment: 6 pages and 1 figur
Dysferlin mediates the cytoprotective effects of TRAF2 following myocardial ischemia reperfusion injury
BACKGROUND: We have demonstrated that tumor necrosis factor (TNF) receptorâassociated factor 2 (TRAF2), a scaffolding protein common to TNF receptors 1 and 2, confers cytoprotection in the heart. However, the mechanisms for the cytoprotective effects of TRAF2 are not known. METHODS/RESULTS: Mice with cardiacârestricted overexpression of low levels of TRAF2 (MHCâTRAF2(LC)) and a dominant negative TRAF2 (MHCâTRAF2(DN)) were subjected to ischemia (30âminute) reperfusion (60âminute) injury (I/R), using a Langendorff apparatus. MHCâTRAF2(LC) mice were protected against I/R injury as shown by a significant â27% greater left ventricular (LV) developed pressure after I/R, whereas mice with impaired TRAF2 signaling had a significantly â38% lower LV developed pressure, a â41% greater creatine kinase (CK) release, and â52% greater Evans blue dye uptake after I/R, compared to LM. Transcriptional profiling of MHCâTRAF2(LC) and MHCâTRAF2(DN) mice identified a calciumâtriggered exocytotic membrane repair protein, dysferlin, as a potential cytoprotective gene responsible for the cytoprotective effects of TRAF2. Mice lacking dysferlin had a significant â39% lower LV developed pressure, a â20% greater CK release, and â29% greater Evans blue dye uptake after I/R, compared to wildâtype mice, thus phenocopying the response to tissue injury in the MHCâTRAF2(DN) mice. Moreover, breeding MHCâTRAF2(LC) onto a dysferlinânull background significantly attenuated the cytoprotective effects of TRAF2 after I/R injury. CONCLUSION: The study shows that dysferlin, a calciumâtriggered exocytotic membrane repair protein, is required for the cytoprotective effects of TRAF2âmediated signaling after I/R injury
Mycobacteriuria in pulmonary tuberculosis patients in Madras, South India
Three consecutive, entire, early morning urine specimens, collected from each of 137 bacteriologically confirmed pulmonary tuberculosis patients aged more than 12 years were processed for culture of M. tuberculosis by the usual centrifugation method. Of the 411 urine specimens, 5 yielded M. tuberculo- sis. About 50 ml each from 405 of the above specimens, from 135 patients, was also processed for culture by a filtration method and M. tuberculosis was isolated from only one of them. In all, mycobacteriuria was present in 5 (3.6%) of 137 patients (95% confidence inter- val being 1.2% to 8.4%). Of these patients, 92 had no history of previous chemotherapy and 3 (3.3%) excreted tubercle bacilli in Urine (95% confidence interval being 0.6% to 9.3%)
The structure of Green functions in quantum field theory with a general state
In quantum field theory, the Green function is usually calculated as the
expectation value of the time-ordered product of fields over the vacuum. In
some cases, especially in degenerate systems, expectation values over general
states are required. The corresponding Green functions are essentially more
complex than in the vacuum, because they cannot be written in terms of standard
Feynman diagrams. Here, a method is proposed to determine the structure of
these Green functions and to derive nonperturbative equations for them. The
main idea is to transform the cumulants describing correlations into
interaction terms.Comment: 13 pages, 6 figure
Environmentally Persistent Free Radicals (EPFRs). 3. Free versus Bound Hydroxyl Radicals in EPFR Aqueous Solutions
Additional experimental evidence is presented for in vitro generation of hydroxyl radicals because of redox cycling of environmentally persistent free radicals (EPFRs) produced after adsorption of 2-monochlorophenol at 230 °C (2-MCP-230) on copper oxide supported by silica, 5% Cu(II)O/silica (3.9% Cu). A chemical spin trapping agent, 5,5-dimethyl-1-pyrroline-N-oxide (DMPO), in conjunction with electron paramagnetic resonance (EPR) spectroscopy was employed. Experiments in spiked O17 water have shown that âŒ15% of hydroxyl radicals formed as a result of redox cycling. This amount of hydroxyl radicals arises from an exogenous Fenton reaction and may stay either partially trapped on the surface of particulate matter (physisorbed or chemisorbed) or transferred into solution as free OH. Computational work confirms the highly stable nature of the DMPOâOH adduct, as an intermediate produced by interaction of DMPO with physisorbed/chemisorbed OH (at the interface of solid catalyst/solution). All reaction pathways have been supported by ab initio calculations
Fog computing security: a review of current applications and security solutions
Fog computing is a new paradigm that extends the Cloud platform model by providing computing resources on the edges of a network. It can be described as a cloud-like platform having similar data, computation, storage and application services, but is fundamentally different in that it is decentralized. In addition, Fog systems are capable of processing large amounts of data locally, operate on-premise, are fully portable, and can be installed on heterogeneous hardware. These features make the Fog platform highly suitable for time and location-sensitive applications. For example, Internet of Things (IoT) devices are required to quickly process a large amount of data. This wide range of functionality driven applications intensifies many security issues regarding data, virtualization, segregation, network, malware and monitoring. This paper surveys existing literature on Fog computing applications to identify common security gaps. Similar technologies like Edge computing, Cloudlets and Micro-data centres have also been included to provide a holistic review process. The majority of Fog applications are motivated by the desire for functionality and end-user requirements, while the security aspects are often ignored or considered as an afterthought. This paper also determines the impact of those security issues and possible solutions, providing future security-relevant directions to those responsible for designing, developing, and maintaining Fog systems
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