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Nasal lavage with mupirocin has the potential to reduce sinonasal morbidity in endoscopic endonasal approaches for skull base surgery.
To evaluate the effects of nasal lavage with and without mupirocin after endoscopic endonasal skull base surgery.
A pilot randomised, controlled trial was conducted on 20 adult patients who had undergone endoscopic endonasal approaches for skull base lesions. These patients were randomly assigned to cohorts using nasal lavages with mupirocin or without mupirocin. Patients were assessed in the out-patient clinic, one week and one month after surgery, using the 22-item Sino-Nasal Outcome Test questionnaire and nasal endoscopy.
Patients in the mupirocin nasal lavage group had lower nasal endoscopy scores post-operatively, and a statistically significant larger difference in nasal endoscopy scores at one month compared to one week. The mupirocin nasal lavage group also showed better Sino-Nasal Outcome Test scores at one month compared to the group without mupirocin.
Nasal lavage with mupirocin seems to yield better outcomes regarding patients’ symptoms and endoscopic findings.
Predictive analytics in health is a complex, transdisciplinary field requiring collaboration across diverse scientific and stakeholder groups. Pilot implementation of participatory research to foster team science in predictive analytics through a partnered-symposium and funding competition. In total, 85 stakeholders were engaged across diverse translational domains, with a significant increase in perceived importance of early inclusion of patients and communities in research. Participatory research approaches may be an effective model for engaging broad stakeholders in predictive analytics.
This paper presents the results of a detailed experimental investigation into the effectiveness of sinusoidal leading edge serrations on aerofoils for the reduction of the noise generated by the interaction with turbulent flow. A detailed parametric study is performed to investigate the sensitivity of the noise reductions to the serration amplitude and wavelength. The study is primarily performed on flat plates in an idealized turbulent flow, which we demonstrate captures the same behaviour as when identical serrations are introduced onto three-dimensional aerofoils. The influence on the noise reduction of the turbulence integral length scale is also studied. An optimum serration wavelength is identified whereby maximum noise reductions are obtained, corresponding to when the transverse integral length scale is approximately one-fourth the serration wavelength. This paper proves that, at the optimum serration wavelength, adjacent valley sources are excited incoherently. One of the most important findings of this paper is that, at the optimum serration wavelength, the sound power radiation from the serrated aerofoil varies inversely proportional to the Strouhal number
are frequency, serration amplitude and flow speed, respectively. A simple model is proposed to explain this behaviour. Noise reductions are observed to generally increase with increasing frequency until the frequency at which aerofoil self-noise dominates the interaction noise. Leading edge serrations are also shown to reduce aerofoil self-noise. The mechanism for this phenomenon is explored through particle image velocimetry measurements. Finally, the lift and drag of the serrated aerofoil are obtained through direct measurement and compared against the straight edge baseline aerofoil. It is shown that aerodynamic performance is not substantially degraded by the introduction of the leading edge serrations on the aerofoil.
Polymeric materials are widely used in power generation and energy storage applications. Deoxyribonucleic acid (DNA) biopolymer-based hybrids have been found to display interesting electrical characteristics, such as a relatively high dielectric constant, good resistivity and dielectric breakdown behavior, and are promising as insulating dielectrics for capacitor applications. This research describes the processing, test structure design, and electrical characterization of DNA-sol-gel hybrids for energy storage applications.
Ferroelectric film-on-foil capacitors hold special promise to replace discrete passive components in the development of electronic devices that require greater performance and smaller size. We have grown ferroelectric Pb0.92La0.08Zr0.52Ti0.48O3 (PLZT) films on nickel substrates by chemical solution deposition. The dielectric properties were determined for samples of ≈1.15-μm-thick PLZT film grown on LaNiO3-buffered nickel substrates. Measurements on these samples yielded a dielectric constant of ≈1300, dielectric loss (tan δ) of ≈0.05, and leakage current density of ≈7 × 10-9 A/cm2. An energy density of ≈74 J/cm3 was measured at room temperature with 250-μm-diameter capacitors. Highly accelerated lifetime tests were conducted at 100°C to determine the reliability of the ≈1.15-μm-thick film-on-foil capacitors under field stress conditions (with applied electric field from 8.7 × 105 V/cm to 1.3 × 106 V/cm). The breakdown behavior of the PLZT film-on-foil capacitors was evaluated by Weibull analysis. A voltage acceleration factor of ≈-6.3 was obtained. From the test results, a mean time to failure of >3000 hr was projected for capacitors operated at 100°C with ≈2.6 × 105 V/cm dc electric field.
Ferroelectric film-on-foil capacitors hold special promise to replace discrete passive components in the development of electronic devices that require greater performance and smaller size. We have deposited Pb0.92La0.08Zr0.52Ti0.48O3 (PLZT) films on base metal foils to form film-on-foil capacitor sheets that can be embedded into printed circuit boards. The rootmean-square surface roughness was determined to be ≍3 nm for 1.15-μm-thick PLZT films on LaNiO3-buffered Ni foils. The following dielectric properties were measured: relative permittivity of ≍1300 and dielectric loss (tan δ) of ≍0.05, leakage current density of 6.6 × 10−9 A/cm2 at 25°C and 1.4 × 10−8 A/cm2 at 150°C, and mean breakdown strength >2.5 MV/cm. A remnant polarization (Pr) of ≍33 μC/cm2 and coercive field strength (Ec) of ≍50 kV/cm were observed with a maximum voltage of 300 V applied during the P-E loop measurement. The energy storage capability of the dielectric film is ≍45 J/cm3.
Nanofocusing, high-resolution X-ray optics demand good surface quality, the absence of tapered sidewalls, and a depth reaching into tens, sometimes hundreds of microns, all requirements that must be satisfied over large areas. In this report, we discuss our motivation for choosing group IV materials (predominantly Si, and C in its diamond form) for nanofocusing and high resolution in the hard X-ray portion of the spectrum. We elaborate on the design and nanofabrication procedures, and detail the etching parameters that offer a path for overcoming obstacles in making better optics. We briefly review tests for the assessing the quality of the optics.
Biphasic calcium phosphates have received considerable attention due to their optimum dissolution rate in the human body after implantation. These materials are composed of hydroxyapatite (HA) and resorbable tricalcium phosphate (TCP). In the present investigation, HA whiskers are reinforced into TCP to enhance the mechanical properties of this biphasic composite. Various amounts (30-50 wt%) HA whiskers are reinforced in TCP matrix. Microstructural characterization has been carried out using field-emission scanning electron microscope. Mechanical properties have been investigated by microindentation in a universal testing machine (UTM). As TCP is resorbable, it will dissolve in body fluid and there is a strong possibility for the faceted HA whiskers to interact with functional groups present in the body fluid surroundings.
A systematic study has been made of the influence of the deposition conditions on the properties of SiO2 grown by liquid phase deposition (LPD), and a-Si:H manufactured by plasma enhanced chemical vapour deposition (PECVD) with the novel facility of source-gas heating. It is demonstrated that LPD-SiO2 can be grown at 50°C with good dielectric properties. Material has been produced with a resistivity of 1015 &cm and a dielectric strength of 9 MVcm-1.The oxide was found to have a negative fixed oxide charge of 4 × 1011 cm−2, with a dielectric constant of 3.08 and a refractive index of 1.44. In the case of a-Si:H, pre-heating the source gases has enabled material to be grown at 125°C with a hydrogen content of ∼ 10 at%, with a predominance of monohydride bonding and a photosensitivity of ∼ 104. Inverted-staggered thin film transistors have been fabricated incorporating these films with an On/Off ratio of five orders of magnitude, a sub-threshold slope of 1.3 Vdecade−1 and a field effect mobility of 0.20 cm2V−1s−1
We have performed x-ray photon correlation spectroscopy (XPCS) measurements on a polymer-bilayer system comprised of 100 nm polystyrene film on top of an 80 nm polybromostyrene film, supported on a Si substrate. In order to distinguish the dynamics at the top interface from that at the polymer-polymer interface we have performed the measurement at grazing incidence. In this geometry, a standing wave is set up in the film. We derive a relation for the intensity of the standing wave and the resulting diffuse scattering. This model is compared with the measured diffuse scattering from which we extract a value of 0.7±0.4 dyne/cm for the surface tension between PS and PBrS at 180C. XPCS was then measured in each of two standing wave conditions, first where diffuse scattering only occurs at the polymer-vacuum interface and then where it only occurs at the interior polymer-polymer interface. The measured time correlation functions for each of the two interfaces show clear differences, with the polymer-polymer interface exhibiting much slower dynamics.
We positionally match sources observed by the Sloan Digital Sky Survey (SDSS), the Two Micron All Sky Survey (2MASS), and the Faint Images of the Radio Sky at Twenty-cm (FIRST) survey. Practically all 2MASS sources are matched to an SDSS source within 2 arcsec; ~11% of them are optically resolved galaxies and the rest are dominated by stars. About 1/3 of FIRST sources are matched to an SDSS source within 2 arcsec; ~80% of these are galaxies and the rest are dominated by quasars. Based on these results, we project that by the completion of these surveys the matched samples will include about 107 stars and 106 galaxies observed by both SDSS and 2MASS, and about 250,000 galaxies and 50,000 quasars observed by both SDSS and FIRST. Here we present a preliminary analysis of the optical, infrared and radio properties for the extragalactic sources from the matched samples. In particular, we find that the fraction of quasars with stellar colors missed by the SDSS spectroscopic survey is probably not larger than ~10%, and that the optical colors of radio-loud quasars are ~0.05 mag. redder (with 4σ significance) than the colors of radio-quiet quasars.
Microhardness testing is widely used for characterizing the mechanical properties of both bulk materials and thin films. Although this technique is usually associated with hardness measurements, fracture properties of brittle materials can also be studied with cracking associated with microhardness indentations. It is well known that the length of radial cracks emanating from the comers of indents made with Vickers and Berkovich indenters is related to the fracture toughness of the material. In the present study, microhardness testing has been used to follow the evolution of the mechanical properties of a 10 nm.Cu/200 nm. Ni(V)/300 nm. Al(Cu) thin film deposited on a Si substrate. Composite hardness and fracture toughness have been followed as a function of heat treatment temperatures and times and were found to be dependent on both variables. The roles of residual stresses, interdiffusion, and intermediate phase formation in the observed variation in hardness and fracture toughness are discussed.