5,672 research outputs found
Per Urethral Catheterisation: Microbial Growth Incidence and its Management
The urinary tract is the most common site of nosocomial infections accounting for more than 40% of the total number reported by acute care hospitals and affecting approximately 600,000 patients per year. Catheter Associated Urinary Tract Infection (CAUTI) defines in terms of “bacteriuria” and “urinary tract infection” frequently. Bacteriuria or funguria levels >103 colony- forming units (CFU) have been shown to be highly predictive of CAUTI, given that these levels increase to 105 CFU within 24 to 48 hours. In Indian population, catheterassociated urinary tract infection (CAUTI) is an important cause of morbidity and mortality, affecting all age groups. Biofilm is the predominant mode of growth in aquatic ecosystems and, as such, plays a central role in the pathogenesis of Catheter Associated Urinary Tract Infections (CAUTI). The present review focuses to evaluate the incidence and pattern of microbes in catheter associated urinary tract infection and provides information about the etiology of CAUTI. Most of the studies concluded that gram negative pathogen E.coli showed the highest incidence rate and other pathogens like Klebsiella pneumonia, Pseudomonas aeruginosa, and staphylococcus species also having the incidence rate in the patient having CAUTI. The antibiotic resistance pattern showed the variation in resistance and sensitivity of antibiotics against the pathogens. The present study focuses on the incidence of the microbial growth in patient having catheterization and also elucidates the antibiotic sensitivity pattern. It is necessary to determine the antibiotic resistance and sensitivity status during and after the catheterization
A Nearly Scale Invariant Spectrum of Gravitational Radiation from Global Phase Transitions
Using a large N sigma model approximation we explicitly calculate the power
spectrum of gravitational waves arising from a global phase transition in the
early universe and we confirm that it is scale invariant, implying an
observation of such a spectrum may not be a unique feature of inflation.
Moreover, the predicted amplitude can be over 3 orders of magnitude larger than
the naive dimensional estimate, implying that even a transition that occurs
after inflation may dominate in Cosmic Microwave Background polarization or
other gravity wave signals.Comment: 4 pages, PRL published versio
Aharonov-Bohm Radiation of Fermions
We analyze Aharonov-Bohm radiation of charged fermions from oscillating
solenoids and cosmic strings. We find that the angular pattern of the radiation
has features that differ significantly from that for bosons. For example,
fermionic radiation in the lowest harmonic is approximately isotropically
distributed around an oscillating solenoid, whereas for bosons the radiation is
dipolar. We also investigate the spin polarization of the emitted
fermion-antifermion pair. Fermionic radiation from kinks and cusps on cosmic
strings is shown to depend linearly on the ultraviolet cut-off, suggesting
strong emission at an energy scale comparable to the string energy scale.Comment: 14 pages, 6 figures. Version 2: Expanded discussion on boundary
conditions obeyed by Dirac equation mode functions (in Section V B).
Acknowledgements and references added. Version 3: Minor changes made in
response to referee's comment
Fuselage shell and cavity response measurements on a DC-9 test section
A series of fuselage shell and cavity response measurements conducted on a DC-9 aircraft test section are described. The objectives of these measurements were to define the shell and cavity model characteristics of the fuselage, understand the structural-acoustic coupling characteristics of the fuselage, and measure the response of the fuselage to different types of acoustic and vibration excitation. The fuselage was excited with several combinations of acoustic and mechanical sources using interior and exterior loudspeakers and shakers, and the response to these inputs was measured with arrays of microphones and accelerometers. The data were analyzed to generate spatial plots of the shell acceleration and cabin acoustic pressure field, and corresponding acceleration and pressure wavenumber maps. Analysis and interpretation of the spatial plots and wavenumber maps provided the required information on modal characteristics, structural-acoustic coupling, and fuselage response
Improvements to the finite-difference time-domain method for calculating radar cross section of a perfectly conducting target
Journal ArticleAbstract -The finite-difference time-domain (FDTD) method has been used extensively to calculate scattering and absorption from both dielectric objects and perfectly conducting objects. Several improvements to the FDTD method for calculating the radar cross section (RCS) of a perfectly conducting target are presented in this paper. Sinusoidal and pulsed FDTD excitations are compared to determine an efficient method of finding the frequency response of targets. The maximum cell size, the minimum number of external cells, and a new method to eliminate field storage in the shielded internal volume of perfect conductors to reduce the computer storage requirements of FDTD are discussed. The magnetic field dc offset induced by surface currents on perfectly conductive objects is observed and its effects removed by postprocessing to achieve convergence of RCS calculations. RCS calculations using the FDTD method in two dimensions are presented for both square and circular infinite cylinders illuminated by both TE and TM polarized plane waves. The RCS of a metal cube in three dimensions is also presented. Good agreement between FDTD calculations and theoretical values is achieved for all cases, and parameters necessary to achieve this agreement are examined
UHB demonstrator interior noise control flight tests and analysis
The measurement and analysis of MD-UHB (McDonnell Douglas Ultra High Bypass) Demonstrator noise and vibration flight test data are described as they relate to passenger cabin noise. The analyses were done to investigate the interior noise characteristics of advanced turboprop aircraft with aft-mounted engines, and to study the effectiveness of selected noise control treatments in reducing passenger cabin noise. The UHB Demonstrator is an MD-80 test aircraft with the left JT8D engine replaced with a prototype UHB engine. For these tests, the UHB engine was a General Electric Unducted Fan, with either 8x8 or 10x8 counter-rotating propeller configurations. Interior noise level characteristics were studied for several altitudes and speeds, with emphasis on high altitude (35,000 ft), high speed (0.75 Mach) cruise conditions. The effectiveness of several noise control treatments was evaluated based on cabin noise measurements. The important airborne and structureborne transmission paths were identified for both tonal and broadband sources using the results of a sound intensity survey, exterior and interior noise and vibration data, and partial coherence analysis techniques. Estimates of the turbulent boundary layer pressure wavenumber-frequency spectrum were made, based on measured fuselage noise levels
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