412 research outputs found
Shellac-Structure, Characteristics & Modification
The paper attempts to document upto date status of the structural studies of Shellac. Attempt has also been made to review the literature on modification of shellac molecules to make it more acceptable to meet the growing demand of the users
Applications of Personalised Phage Therapy highlighting the importance of Bacteriophage Banks against Emerging Antimicrobial Resistance
Emerging antibiotic resistance is one of the most important microbiological issues of the 21st century. This poses a query regarding the future use of antibiotics and availability of other promising therapeutic alternatives. The awareness about antibiotic misuse has improved insufficiently and is evident by the increased incidences of multidrug resistant infections globally. Amongst different antibacterial therapeutic approaches phage therapy has created a niche of its own due to continuous use for treatment of human infections in Eastern Europe. Synergistic compounds along with phages have also been proposed as a better alternative compared to antibiotics or phage alone for treatment of chronic cases and seriously debilitating diseases. As such, why not allow custom made phage therapy for treatment of chronic infections? However, the success of phage therapy will depend upon instant availability of characterised bacteriophages from bacteriophage banks which may serve as the major catalyst in bringing Phage Therapy to main stream treatment alternatives or in combination therapy at least. In the current article we present a glimpse of comprehensive approach about utility of bacteriophage banks and further present personalised phage therapy in a synergistic role with antibiotics to overcome emerging antimicrobial resistance
Survey of Cochlear Implant User Satisfaction with the Neptuneā¢ Waterproof Sound Processor
A multi-center self-assessment survey was conducted to evaluate patient satisfaction with the Advanced Bionics Neptuneā¢ waterproof sound processor used with the AquaMicā¢ totally submersible microphone. Subjective satisfaction with the different Neptuneā¢ wearing options, comfort, ease of use, sound quality and use of the processor in a range of active and water related situations were assessed for 23 adults and 73 children, using an online and paper based questionnaire. Upgraded subjects compared their previous processor to the Neptuneā¢. The Neptuneā¢ was most popular for use in general sports and in the pool. Subjects were satisfied with the sound quality of the sound processor outside and under water and following submersion. Seventy-eight percent of subjects rated waterproofness as being very useful and 83% of the newly implanted subjects selected waterproofness as one of the reasons why they chose the Neptuneā¢ processor. Providing a waterproof sound processor is considered by cochlear implant recipients to be useful and important and is a factor in their processor choice. Subjects reported that they were satisfied with the Neptuneā¢ sound quality, ease of use and different wearing options
Electron-Impact Excitation from the (4pāµ5s) Metastable States of Krypton
Theoretical results from multistate semirelativistic Breit-Pauli R-matrix calculations and two first-order distorted-wave calculations are presented for electron-impact excitation of krypton from the (4p55s) J = 0,2 metastable states to the (4p55s) and (4p55p) manifolds. Except for a few cases, in which the method to account for relativistic effects becomes surprisingly critical, fair overall agreement between the predictions from the various theoretical models is achieved for intermediate and high energies. However, significant discrepancies remain with the few available experimental data
Electron-Impact Excitation to the 4pāµ5s and 4pāµ5p Levels of Kr | Using Different Distorted-Wave and Close-Coupling Methods
Electron-impact excitation of the 4p55s and 4p55p levels of Kr I has been investigated in detail by calculating cross sections using distorted-wave and close-coupling approaches. The results are presented from the excitation thresholds up to 50 eV incident energy. They are contrasted among the different calculations and compared with other theoretical predictions and experimental data. Significant disagreement is found with many of the recent experimental data of Chilton et al. [Phys. Rev. A 62, 032714 (2000)]
An inhomogeneous universe with thick shells and without cosmological constant
We build an exact inhomogeneous universe composed of a central flat Friedmann
zone up to a small redshift , a thick shell made of anisotropic matter, an
hyperbolic Friedmann metric up to the scale where dimming galaxies are observed
() that can be matched to a hyperbolic Lema\^{i}tre-Tolman-Bondi
spacetime to best fit the WMAP data at early epochs. We construct a general
framework which permits us to consider a non-uniform clock rate for the
universe. As a result, both for a uniform time and a uniform Hubble flow, the
deceleration parameter extrapolated by the central observer is always positive.
Nevertheless, by taking a non-uniform Hubble flow, it is possible to obtain a
negative central deceleration parameter, that, with certain parameter choices,
can be made the one observed currently. Finally, it is conjectured a possible
physical mechanism to justify a non-uniform time flow.Comment: Version published in Class. Quantum gra
Local Void vs Dark Energy: Confrontation with WMAP and Type Ia Supernovae
It is now a known fact that if we happen to be living in the middle of a
large underdense region, then we will observe an "apparent acceleration", even
when any form of dark energy is absent. In this paper, we present a "Minimal
Void" scenario, i.e. a "void" with minimal underdensity contrast (of about
-0.4) and radius (~ 200-250 Mpc/h) that can, not only explain the supernovae
data, but also be consistent with the 3-yr WMAP data. We also discuss
consistency of our model with various other measurements such as Big Bang
Nucleosynthesis, Baryon Acoustic Oscillations and local measurements of the
Hubble parameter, and also point out possible observable signatures.Comment: Minor numerical errors and typos corrected, references adde
"Swiss-Cheese" Inhomogeneous Cosmology & the Dark Energy Problem
We study an exact swiss-cheese model of the Universe, where inhomogeneous LTB
patches are embedded in a flat FLRW background, in order to see how
observations of distant sources are affected. We find negligible integrated
effect, suppressed by (L/R_{H})^3 (where L is the size of one patch, and R_{H}
is the Hubble radius), both perturbatively and non-perturbatively. We
disentangle this effect from the Doppler term (which is much larger and has
been used recently \cite{BMN} to try to fit the SN curve without dark energy)
by making contact with cosmological perturbation theory.Comment: 35 pages, 6 figure
Utility of the FebriDx point-of-care assay in supporting a triage algorithm for medical admissions with possible COVID-19: an observational cohort study
Objective: To evaluate a triage algorithm used to identify and isolate patients with suspected COVID-19 among medical patients needing admission to hospital using simple clinical criteria and the FebriDx assay.
Design:: Retrospective observational cohort.
Setting Large acute National Health Service hospital in London, UK.
Participants: All medical admissions from the emergency department between 10 August 2020 and 4 November 2020 with a valid SARS-CoV-2 RT-PCR result.
Interventions: Medical admissions were triaged as likely, possible or unlikely COVID-19 based on clinical criteria. Patients triaged as possible COVID-19 underwent FebriDx lateral flow assay on capillary blood, and those positive for myxovirus resistance protein A (a host response protein) were managed as likely COVID-19.
Primary outcome measures: Diagnostic accuracy (sensitivity, specificity and predictive values) of the algorithm and the FebriDx assay using SARS-CoV-2 RT-PCR from nasopharyngeal swabs as the reference standard.
Results: 4.0% (136) of 3443 medical admissions had RT-PCR confirmed COVID-19. Prevalence of COVID-19 was 46% (80/175) in those triaged as likely, 4.1% (50/1225) in possible and 0.3% (6/2033) in unlikely COVID-19. Using a SARS-CoV-2 RT-PCR reference standard, clinical triage had sensitivity of 96% (95% CI 91% to 98%) and specificity of 61.5% (95% CI 59.8% to 63.1%), while the triage algorithm including FebriDx had sensitivity of 93% (95% CI 87% to 96%) and specificity of 86.4% (95% CI 85.2% to 87.5%). While 2033 patients were deemed not to require isolation using clinical criteria alone, the addition of FebriDx to clinical triage allowed a further 826 patients to be released from isolation, reducing the need for isolation rooms by 9.5 per day, 95%āCI 8.9 to 10.2. Ten patients missed by the algorithm had mild or asymptomatic COVID-19.
Conclusions: A triage algorithm including the FebriDx assay had good sensitivity and was useful to ārule-outā COVID-19 among medical admissions to hospital
LTB solutions in Newtonian gauge: from strong to weak fields
Lemaitre-Tolman-Bondi (LTB) solutions are used frequently to describe the
collapse or expansion of spherically symmetric inhomogeneous mass distributions
in the Universe. These exact solutions are obtained in the synchronous gauge
where nonlinear dynamics (with respect to the FLRW background) induce large
deviations from the FLRW metric. In this paper we show explicitly that this is
a gauge artefact (for realistic sub-horizon inhomogeneities). We write down the
nonlinear gauge transformation from synchronous to Newtonian gauge for a
general LTB solution using the fact that the peculiar velocities are small. In
the latter gauge we recover the solution in the form of a weakly perturbed FLRW
metric that is assumed in standard cosmology. Furthermore we show how to obtain
the LTB solutions directly in Newtonian gauge and illustrate how the Newtonian
approximation remains valid in the nonlinear regime where cosmological
perturbation theory breaks down. Finally we discuss the implications of our
results for the backreaction scenario.Comment: 17 page
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