19,817 research outputs found
Thick transducers used for generating short-duration stress pulses in thin specimens
By generating short stress pulses with thick transducers, the pulse-echo method for determining sound velocities and acoustic attenuation can be applied to thin specimens. The stress pulses enter a specimen where one pulse is reflected several times before a succeeding pulse enters the specimen
Sufficient conditions for the existence of Q-balls in gauge theories
We formulate a set of simple sufficient conditions for the existence of
Q-balls in gauge theories.Comment: 5 page
The XMM-Newton spectral-fit database
The XMM-Newton spectral-fit database is an ongoing ESA funded project aimed
to construct a catalogue of spectral-fitting results for all the sources within
the XMM-Newton serendipitous source catalogue for which spectral data products
have been pipeline-extracted (~ 120,000 X-ray source detections). The
fundamental goal of this project is to provide the astronomical community with
a tool to construct large and representative samples of X-ray sources by
allowing source selection according to spectral properties.Comment: Conference proceedings of IAU Symposium 304: Multiwavelength AGN
surveys and studie
Methods for the identification of material parameters in distributed models for flexible structures
Theoretical and numerical results are presented for inverse problems involving estimation of spatially varying parameters such as stiffness and damping in distributed models for elastic structures such as Euler-Bernoulli beams. An outline of algorithms used and a summary of computational experiences are presented
On a generalized quantum SWAP gate
The SWAP gate plays a central role in network designs for qubit quantum computation. However, there has been a view to generalize qubit quantum computing to higher dimensional quantum systems. In this paper we construct a generalized SWAP gate using only instances of the generalized controlled-NOT gate to cyclically permute the states of d qudits for d prime
Head and Neck Manifestations of Eosinophilic Granulomatosis with Polyangiitis: A Systematic Review.
OBJECTIVE: To conduct the first and only systematic review of the existing literature on head and neck manifestations of eosinophilic granulomatosis with polyangiitis to guide clinical decision making for the otolaryngologist.
DATA SOURCES: PubMed, Cochrane Library, Scopus, and LILACS.
REVIEW METHODS: A systematic review of the aforementioned sources was conducted per the PRISMA guidelines.
RESULTS: From an initial 574 studies, 28 trials and reports were included, accounting for a total of 1175 patients with eosinophilic granulomatosis with polyangiitis. Among clinical and cohort studies, 48.0% to 96.0% of all included patients presented with head and neck manifestations. In a distinct group of patients detailed in case reports describing patients presenting with head and neck manifestations, patients on average fulfilled 4.6 diagnostic criteria per the American College of Rheumatology. Furthermore, 95.8% of reported cases were responsive to steroids, and 60% required additional therapy.
CONCLUSION: Otolaryngologists are in a unique position for the early diagnosis and prevention of late complications of eosinophilic granulomatosis with polyangiitis. The American College of Rheumatology criteria should be relied on in the diagnostic workup. Close surveillance of these patients in a multidisciplinary fashion and with baseline complete blood counts, chest radiographs, and autoimmune laboratory tests is often necessary. Such patients with head and neck manifestations of the disease are nearly always responsive to steroids and often require additional immunosuppressive therapy or surgical intervention in cases of cranial neuropathies, temporal bone involvement, and refractory symptoms
Nonet Symmetry and Two-Body Decays of Charmed Mesons
The decay of charmed mesons into pseudoscalar (P) and vector (V) mesons is
studied in the context of nonet symmetry. We have found that it is badly broken
in the PP channels and in the P sector of the PV channels as expected from the
non-ideal mixing of the \eta and the \eta'. In the VV channels, it is also
found that nonet symmetry does not describe the data well. We have found that
this discrepancy cannot be attributed entirely to SU(3) breaking at the usual
level of 20--30%. At least one, or both, of nonet and SU(3) symmetry must be
very badly broken. The possibility of resolving the problem in the future is
also discussed.Comment: 9 pages, UTAPHY-HEP-
Effects of arcing due to spacecraft charging on spacecraft survival
A quantitative assessment of the hazard associated with spacecraft charging and arcing on spacecraft systems is presented. A literature survey on arc discharge thresholds and characteristics was done and gaps in the data and requirements for additional experiments were identified. Calculations of coupling of arc discharges into typical spacecraft systems were made and the susceptibility of typical spacecraft to disruption by arc discharges was investigated. Design guidelines and recommended practices to reduce or eliminate the threat of malfunction and failures due to spacecraft charging/arcing were summarized
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