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There is growing concern over a future shortfall in provision of UK otolaryngology consultants. There is a declining rate of applications to otolaryngology specialty training in the UK.
This study aimed to systematically review the literature to establish what factors influence medical students’ and junior doctors’ decision to pursue a career in otolaryngology.
Medline, Embase and PubMed databases were searched in January 2019. Additional manual reference checks of identified literature were performed.
Eleven articles were included in the review. Common factors that positively influenced the decision to pursue a career in otolaryngology were exposure to the specialty, positive role models and a good work-life balance. Lack of exposure was a consistent deterrent from pursuing a career in otolaryngology.
This review reiterates the need for greater exposure to otolaryngology in the undergraduate curriculum. In addition, mentorship for students with an interest in otolaryngology should be a priority.
Determine the effectiveness of a personal protective equipment (PPE)-free zone intervention on healthcare personnel (HCP) entry hand hygiene (HH) and PPE donning compliance in rooms of patients in contact precautions.
Quasi-experimental, multicenter intervention, before-and-after study with concurrent controls.
All patient rooms on contact precautions on 16 units (5 medical-surgical, 6 intensive care, 5 specialty care units) at 3 acute-care facilities (2 academic medical centers, 1 Veterans Affairs hospital). Observations of PPE donning and entry HH compliance by HCP were conducted during both study phases. Surveys of HCP perceptions of the PPE-free zone were distributed in both study phases.
A PPE-free zone, where a low-risk area inside door thresholds of contact precautions rooms was demarcated by red tape on the floor. Inside this area, HCP were not required to wear PPE.
We observed 3,970 room entries. HH compliance did not change between study phases among intervention units (relative risk [RR], 0.92; P = .29) and declined in control units (RR, 0.70; P = .005); however, the PPE-free zone did not significantly affect compliance (P = .07). The PPE-free zone effect on HH was significant only for rooms on enteric precautions (P = .008). PPE use was not significantly different before versus after the intervention (P = .15). HCP perceived the zone positively; 65% agreed that it facilitated communication and 66.8% agreed that it permitted checking on patients more frequently.
HCP viewed the PPE-free zone favorably and it did not adversely affect PPE or HH compliance. Future infection prevention interventions should consider the complex sociotechnical system factors influencing behavior change.
A multi-scale analysis, ranging from μm → nm → Å-scaie on the influence of thermal treatment on the thermotropic copolyester based on 60 mol% (l,4)-hydroxybenzoic acid (B), 5 mol% (2,6)-hydroxynaphthoic acid (N), 17.5 mol% terephthalic acid (T) and 17.5 mol% biphenol (BP) - COTBP- was carried out. The Å and nm-scale structure was investigated by synchrotron scattering (WAXS and SAXS). Extruded tapes ca. 30 μm thick were annealed at 300 °C under air, without tension. WAXS revealed fibre-like structure with crystalline order, whereas SAXS patterns exhibited diamond-shaped diffuse scattering and discrete meridional scattering elucidating structures along the fibre axis and periodic crystallites. Heat treatment produced roughness reduction, and WAXS patterns showed reflections sharpening indicating an improvement of molecular register and packing (molecular alignment and degree of crystallinity Χ increased). Thermal treatment increased the thermal stability, melting transition and tensile Young’s modulus, E, along extrusion axis, whereas nanoindentation showed decrease of hardness and elastic modulus. Hence, a thermally-induced seif-reinforcing effect was evidenced, with microstructure reorganization correlating with improved thermo-mechanical properties.
To test the hypothesis that long-term care facility (LTCF) residents with Clostridium difficile infection (CDI) or asymptomatic carriage of toxigenic strains are an important source of transmission in the LTCF and in the hospital during acute-care admissions.
A 6-month cohort study with identification of transmission events was conducted based on tracking of patient movement combined with restriction endonuclease analysis (REA) and whole-genome sequencing (WGS).
Veterans Affairs hospital and affiliated LTCF.
The study included 29 LTCF residents identified as asymptomatic carriers of toxigenic C. difficile based on every other week perirectal screening and 37 healthcare facility-associated CDI cases (ie, diagnosis >3 days after admission or within 4 weeks of discharge to the community), including 26 hospital-associated and 11 LTCF-associated cases.
Of the 37 CDI cases, 7 (18·9%) were linked to LTCF residents with LTCF-associated CDI or asymptomatic carriage, including 3 of 26 hospital-associated CDI cases (11·5%) and 4 of 11 LTCF-associated cases (36·4%). Of the 7 transmissions linked to LTCF residents, 5 (71·4%) were linked to asymptomatic carriers versus 2 (28·6%) to CDI cases, and all involved transmission of epidemic BI/NAP1/027 strains. No incident hospital-associated CDI cases were linked to other hospital-associated CDI cases.
Our findings suggest that LTCF residents with asymptomatic carriage of C. difficile or CDI contribute to transmission both in the LTCF and in the affiliated hospital during acute-care admissions. Greater emphasis on infection control measures and antimicrobial stewardship in LTCFs is needed, and these efforts should focus on LTCF residents during hospital admissions.
Coinfection with human immunodeficiency virus (HIV) and viral hepatitis is associated with high morbidity and mortality in the absence of clinical management, making identification of these cases crucial. We examined characteristics of HIV and viral hepatitis coinfections by using surveillance data from 15 US states and two cities. Each jurisdiction used an automated deterministic matching method to link surveillance data for persons with reported acute and chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infections, to persons reported with HIV infection. Of the 504 398 persons living with diagnosed HIV infection at the end of 2014, 2.0% were coinfected with HBV and 6.7% were coinfected with HCV. Of the 269 884 persons ever reported with HBV, 5.2% were reported with HIV. Of the 1 093 050 persons ever reported with HCV, 4.3% were reported with HIV. A greater proportion of persons coinfected with HIV and HBV were males and blacks/African Americans, compared with those with HIV monoinfection. Persons who inject drugs represented a greater proportion of those coinfected with HIV and HCV, compared with those with HIV monoinfection. Matching HIV and viral hepatitis surveillance data highlights epidemiological characteristics of persons coinfected and can be used to routinely monitor health status and guide state and national public health interventions.
The paper analyzes the issues relating to the applicability of innovative material systems for flexible composite armors. The authors made several samplings of aramid fibers (Kevlar 49) by replacing the epoxy resin base, which is often described in the literature, with the thermoplastic matrix - polyethylene (HDPE) and polypropylene (PP). The samples were fired with .38 Special Full Metal Jacketed (FMJ) ammunition produced by the S&B Company, and then the process of firing was modeled in the ABAQUS program. The advantages and disadvantages of the new material system including the possibility of its use in the construction of hybrid composite armors have been presented on the basis of the results of numerical analyses and ballistic tests.
The 1994 sale of radio spectrum for “personal communication services” (PCS) marked a sharp change in policy by the US Federal Communications Commission (FCC). Before turning to auctions the FCC had allocated valuable spectrum on the basis of comparative hearings (also known as “beauty contests”) and lotteries. Nobel laureate Ronald Coase long advocated that market-based mechanisms would improve the allocation of scarce spectrum resources, but his early insights were ignored for decades . The PCS auction raised over six hundred million dollars for the US treasury and it was widely considered a success. Several authors discuss the advantages and disadvantages of auctions and beauty contests for allocating scarce spectrum [2, 3, 4]. For example, some argue that financially strong bidders might have advantages over weaker bidders in an auction, while others argue that with efficient capital markets such differences should be less of a concern. Nowadays, spectrum is predominantly assigned by auction, both in the US and elsewhere [5, 6], and in this paper we focus on questions of auction design.
The simultaneous multi-round auction (SMRA), which was designed for the US FCC in the early 90's has been the standard auction format for selling spectrum world wide for many years. It auctions multiple licenses for sale in parallel and uses simple activity rules which forces bidders to be active from the start. Despite the simplicity of its rules there can be considerable strategic complexity in the SMRA when there are synergies between licenses that cover adjacent geographic regions or between licenses in different frequency bands. Bidders who compete aggressively for a certain combination of licenses risk being exposed when they end up winning an inferior subset at high prices. When bidders rationally anticipate this exposure problem, competition will be suppressed with adverse consequences for the auction's performance. The exposure problem has led auction designers to consider combinatorial auctions, which enable bidders to express their preferences for an entire set of licenses directly. In fact, the design of spectrum auctions is seen as a pivotal problem im multi-object auction design and successful solutions are a likely role-model for other public or private sector auctions such as transportation or industrial procurement.
Since 2008, the combinatorial clock auction (CCA) has been used by regulators in various countries such as the Austria, Australia, Canada, Denmark, Ireland, the Netherlands, and Switzerland to sell spectrum.
The applicability of volcanic ash deposits on Vatnajökull ice cap, Iceland, as a time reference marker for measuring accumulation by the analysis of time sequential SAR backscatter data was investigated. A volcanic eruption at Grímsvötn caldera, a subglacial volcanic system beneath Vatnajökull, deposited an ash layer north of the vent in early November 2004. This ash layer covered a V-shaped area of ∽88km2 on the glacier surface. The ash fall, which was subsequently buried by snow, reveals a distinct backscatter signal in SAR images. In total, the σ0 backscatter values of 40 ENVISAT-ASAR images were analyzed, covering two post-eruption accumulation periods (4 November 2004 to 31 March 2005 and 25 October 2006 to 14 March 2006). Significant differences over time were observed in the SAR backscatter signals over the deposited ash, which appear to be related to the snow accumulation history. The backscatter signals were compared to meteorological conditions at the time of SAR acquisition and to accumulation data derived from two snow pits, one located within the ash fall. A linear regression analysis between the accumulation data and the SAR backscattering coefficient results in high R2 confidence values (>0.8), indicating that the SAR data can be used for estimating the areal accumulation distribution in areas with an existing ash layer.
Initial infection with the sentinel respiratory pathogen in children with cystic fibrosis (CF), Pseudomonas aeruginosa (Pa), is generally with environmental strains of this ubiquitous organism. The purpose of this study was to evaluate the associations between meteorological and geographical factors and risk of initial Pa acquisition in young children with CF. Using the U.S. Cystic Fibrosis Foundation Patient Registry from 2003 to 2009, 3463 patients met inclusion criteria, of which 48% (n = 1659) acquired Pa during follow-up. From multivariable Weibull regression, increased risk of Pa acquisition was associated with increasing temperature [hazard ratio (HR) per 1 °C: 1·13; 95% confidence interval (CI) 1·08–1·13], dew point (HR per 1 °C: 1·10, 95% CI 1·07–1·13), rainfall (HR per cm: 1·10, 95% CI 1·07–1·12), latitude (HR per 1 °C northing: 1·15, 95% CI 1·11–1·20), longitude (HR per 1 °C easting: 1·01, 95% CI 1·01–1·02) and elevation (HR per 100 m: 1·05, 95% CI 1·03–1·07). These results suggest that environmental factors may play a previously unrecognized role in the aetiology of initial Pa acquisition.
The registration of gamma rays in a spark chamber has been simulated by Monte-Carlo-calculation technique. The spark chamber pictures of these gamma-ray events having a known energy and direction of incidence have been analysed for determinability of direction of incidence. The values obtained for angular resolution depending on energy are compared with values derived by other authors.
The ESRO satellite COS-B carries one single experiment aiming at the measurement of arrival direction and energy of celestial gamma rays with energies between 25 MeV and 10 GeV. The experiment is conventional in design and consists of a veto counter, a wire spark chamber, a telescope and an energy calorimeter.
The energy measurement is obtained by a CsI scintillation crystal of 4.7 radiation length thickness. The expected energy resolution at 100 MeV is 50% FWHM. The other detector elements are designed as to cause the least possible degradation of the energy measurement.
The possibilities for the detection of a small contribution of π -origin gamma rays in the presence of a power-law type background spectrum will be discussed.
The United States Naval Observatory (NAVOBSY) and the Naval Research Laboratory (NRL) are collaborating in a program to apply radio interferometric techniques to the determination of variations in Earth rotation, polar motion, and improved astronomical position reference systems. Investigations of VLBI and connected interferometer techniques and radio sources for astrometic application have been in progress for several years as part of the NRL radio astronomy program, and currently NRL and NAVOBSY are carrying out experimental programs to investigate VLBI time transfer techniques and UT determination using the connected element interferometer of the NRAO in Green Bank. Some previous results of observations using the Green Bank interferometer and proposed plans for operation as a dedicated system over a period of time to evaluate effectiveness for precise determination of Earth rotation parameters are discussed.
Intermetallic titanium aluminides solidifying via the disordered β-phase are of great interest for several high-temperature applications in automotive and aircraft industries. In this paper the thermocyclic oxidation behavior of three β-solidifying γ-TiAl-based alloys at 800°C and 900°C in air, with and without fluorine treatment, is reported for the first time. The behavior of the well-known TNM alloy (Ti-43.5Al-4Nb-1Mo-0.1B, in at.%) is compared with that of two Nb-free model alloys which contain different amounts of Mo (Ti-44Al-3Mo and Ti-44Al-7Mo, in at.%). During thermocyclic high-temperature exposure in air a mixed oxide scale develops on all three untreated alloys. Small additions of fluorine in the subsurface region of the alloys change the oxidation mechanism from mixed oxide scale formation to alumina at both temperatures. The oxidation resistance of the fluorine treated samples was significantly improved compared to the untreated samples.
Ensuring microstructural stability under technical relevant conditions is a determining criterion for the development of innovative high-temperature materials. In this work, the influ-ence of C and Si on the microstructural stability during creep exposure was investigated for a β-solidifying γ-TiAl based alloy with a nominal composition of Ti-43.5Al-4Nb-1Mo-0.1B (in at.%), named TNM. With a two-step heat treatment a microstructure consisting of fine lamellar α2/γ-colonies, surrounded by βo-phase and areas of discontinuous precipitation, starting from the boundaries of the lamellar colonies, was adjusted. Creep tests were carried out to examine the potential of C and Si to prevent microstructural instability during creep and hence improving the creep properties. At 815 °C the discontinuous precipitation process of the TNM alloy continues during ensuing creep testing leading to a reduced creep resistance. In comparison, the minimum creep rate of the TNM-0.3C-0.3Si alloy was significantly decreased caused by the lower βo-phase content and average lamellar spacing within the α2/γ-colonies, the precipitation of p-Ti3AlC carbides and the retarded kinetics of discontinuous precipitation.
The distribution of alloying elements in the constituent phases of a C-containing γ-TiAl based alloy has been characterized locally by atom probe tomography. The major elements of the alloy under consideration – Ti, Al, Nb, and Mo – are distributed uniformly within each of the constituent phases. Furthermore, Mo is preferentially dissolved in the βo-phase, whereas Nb content is similar in all phases. The selected C concentration of the alloy is below the overall solubility limit as no precipitates have been observed. Therefore, C is enriched in the α2-phase, whereas the βo-phase is depleted of C. In addition, βo/γ-interfaces have been prepared by site specific sample preparation and characterized by atom probe tomography. Segregation of Mo and C into the interfaces and their close vicinity was observed.
Ammonia is investigated as nitrogen precursor for molecular beam epitaxy of group III nitrides. With the particular on-surface cracking approach, NH3 is dissociated directly on the growing surface. By this technique, molecular beam epitaxy becomes a serious competitor to metal organic vapor phase epitaxy. Thermodynamic calculations as well as experimental results reveal insights into the growth mechanisms and its differences to the conventional plasma approach. With this knowledge, homoepitaxially GaN can be grown with record linewidths of 0.5 meV in photoluminescence (4 K). GaN layers on c-plane sapphire also reveal reasonable material properties (photoluminescence linewidth 5 meV, n ≈ 1017 cm−3, μ ≈ 220 cm2/Vs). Beside GaN growth, p- and n-doping of GaN as well as the growth of ternary nitrides are discussed. Using the presented ammonia approach UV-LEDs emitting at 370 nm with linewidths as narrow as 12 nm have been achieved.