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This study investigates the impact of primary care utilisation of a symptom-based head and neck cancer risk calculator (Head and Neck Cancer Risk Calculator version 2) in the post-coronavirus disease 2019 period on the number of primary care referrals and cancer diagnoses.
Methods
The number of referrals from April 2019 to August 2019 and from April 2020 to July 2020 (pre-calculator) was compared with the number from the period January 2021 to August 2022 (post-calculator) using the chi-square test. The patients’ characteristics, referral urgency, triage outcome, Head and Neck Cancer Risk Calculator version 2 score and cancer diagnosis were recorded.
Results
In total, 1110 referrals from the pre-calculator period were compared with 1559 from the post-calculator period. Patient characteristics were comparable for both cohorts. More patients were referred on the cancer pathway in the post-calculator cohort (pre-calculator patients 51.1 per cent vs post-calculator 64.0 per cent). The cancer diagnosis rate increased from 2.7 per cent in the pre-calculator cohort to 3.3 per cent in the post-calculator cohort. A lower rate of cancer diagnosis in the non-cancer pathway occurred in the cohort managed using the Head and Neck Cancer Risk Calculator version 2 (10 per cent vs 23 per cent, p = 0.10).
Conclusion
Head and Neck Cancer Risk Calculator version 2 demonstrated high sensitivity in cancer diagnosis. Further studies are required to improve the predictive strength of the calculator.
Benign prostatic hyperplasia is the most common benign neoplasm in males in the United States. It is characterized by lower urinary tract symptoms: weak stream, urinary frequency, urgency, incomplete emptying, hesitancy, nocturia, and acute urinary retention. These symptoms are generally slowly progressive and left untreated can cause irreversible bladder damage. Diagnosis is mostly clinical and based on symptomatology; however, the use of some objective tests can be helpful. Treatment options include lifestyle modification as well as a variety of different pharmacologic agents.
To determine the frequency and predictors of antibiotic escalation in response to the inpatient sepsis screen at our institution.
Design:
Retrospective cohort study.
Setting:
Two affiliated academic medical centers in Los Angeles, California.
Patients:
Hospitalized patients aged 18 years and older who had their first positive sepsis screen between January 1, 2019, and December 31, 2019, on acute-care wards.
Methods:
We described the rate and etiology of antibiotic escalation, and we conducted multivariable regression analyses of predictors of antibiotic escalation.
Results:
Of the 576 cases with a positive sepsis screen, antibiotic escalation occurred in 131 cases (22.7%). New infection was the most documented etiology of escalation, with 76 cases (13.2%), followed by known pre-existing infection, with 26 cases (4.5%). Antibiotics were continued past 3 days in 17 cases (3.0%) in which new or existing infection was not apparent. Abnormal temperature (adjusted odds ratio [aOR], 3.00; 95% confidence interval [CI], 1.91–4.70) and abnormal lactate (aOR, 2.04; 95% CI, 1.28–3.27) were significant predictors of antibiotic escalation. The patient already being on antibiotics (aOR, 0.54; 95% CI, 0.34–0.89) and the positive screen occurred during a nursing shift change (aOR, 0.36; 95% CI, 0.22–0.57) were negative predictors. Pneumonia was the most documented new infection, but only 19 (50%) of 38 pneumonia cases met full clinical diagnostic criteria.
Conclusions:
Inpatient sepsis screening led to a new infectious diagnosis in 13.2% of all positive sepsis screens, and the risk of prolonged antibiotic exposure without a clear infectious source was low. Pneumonia diagnostics and lactate testing are potential targets for future stewardship efforts.
Optimizing pediatric antimicrobial stewardship is challenging. In this retrospective study, we evaluated 515 original e-mails to 482 members of the Sharing Antimicrobial Reports for Pediatric Stewardship (SHARPS) Collaborative electronic mailing list (idlistserv@kids.wustl.edu). The plurality of threads discussed clinical practice guidelines, and pharmacists were most likely to initiate and respond. Representation was geographically diverse within and outside the United States.
To evaluate the impact of the Baby-Friendly Hospital Initiative (BFHI) on breast-feeding initiation and duration overall and according to maternal education.
Design
Quasi-experimental study using data from five states (Alaska, Maine, Nebraska, Ohio, Washington) that participated in the Pregnancy Risk Assessment Monitoring System from 1999 to 2009. Using differences-in-differences models that included year and hospital fixed effects, we compared rates of breast-feeding initiation and duration (any and exclusive breast-feeding for ≥4 weeks) before and after BFHI accreditation between mothers who gave birth in hospitals that were accredited or became accredited and mothers from matched non-BFHI facilities. We stratified analyses into lower and higher education groups.
Setting
Thirteen BFHI hospitals and nineteen matched non-BFHI facilities across five states in the USA.
Subjects
Mothers (n 11 723) who gave birth in BFHI hospitals and mothers (n 13 604) from nineteen matched non-BFHI facilities.
Results
Although we did not find overall differences in breast-feeding initiation between birth facilities that received BFHI accreditation compared with non-Baby-Friendly facilities (adjusted coefficient = 0·024; 95 % CI −0·00, 0·51), breast-feeding initiation increased by 3·8 percentage points among mothers with lower education who delivered in Baby-Friendly facilities (P = 0·05), but not among mothers with higher education (adjusted coefficient = 0·002; 95 % CI −0·04, 0·05). BFHI accreditation also increased exclusive breast-feeding for ≥4 weeks by 4·5 percentage points (P = 0·02) among mothers with lower education who delivered in BFHI facilities.
Conclusions
By increasing breast-feeding initiation and duration among mothers with lower education, the BFHI may reduce socio-economic disparities in breast-feeding.
To explore the views of non-morbidly obese people (BMI 30–40 kg/m2) with type 2 diabetes regarding: (a) the acceptability of bariatric surgery (BS) as a treatment for type 2 diabetes, and (b) willingness to participate in randomised controlled trials comparing BS versus non-surgical intervention.
Background
Despite weight management being a key therapeutic goal in type 2 diabetes, achieving and sustaining weight loss is problematic. BS is an effective treatment for people with morbid obesity and type 2 diabetes; it is less certain whether non-morbidly obese patients (BMI 30–39.9 kg/m2) with type 2 diabetes benefit from this treatment and whether this approach would be cost-effective. Before evaluating this issue by randomised trials, it is important to understand whether BS and such research are acceptable to this population.
Methods
Non-morbidly obese people with type 2 diabetes were purposively sampled from primary care and invited to participate in semi-structured interviews. Interviews explored participants’ thoughts surrounding their diabetes and weight, the acceptability of BS and the willingness to participate in BS research. Data were analysed using Framework Analysis.
Tb doped gadolinium fluoride nanophosphors embedded in an aluminosilicate glass matrix is reported for X-ray imaging applications. The nanocomposite scintillators were prepared by a melt-quench method followed by annealing. The GdF3:Tb nanophosphors precipitated within the oxide glass matrix during the processing and their luminescence and scintillation properties were investigated.
GaN and InGaN layers were grown on annealed 20 and 50nm Al2O3/ZnO substrates by metalorganic chemical vapor deposition (MOCVD). GaN was only observed by high resolution x-ray diffraction (HRXRD) on 20 nm Al2O3/ZnO substrates. Room temperature photoluminescence (RT-PL) showed the red shift of the GaN near band-edge emission, which might be from oxygen incorporation forming a shallow donor-related level in GaN. HRXRD measurements revealed that (0002) InGaN layers were also successfully grown on 20nm Al2O3/ZnO substrates. In addition, thick InGaN layers (∼200-300nm) were successfully grown on Al2O3/ZnO and bare ZnO substrates. These results are significant as previous studies showed decomposition of the layer at InGaN thicknesses of 100nm or less.
Atomic layer deposition (ALD) of Al2O3 is used as a passivation layer on ZnO substrates before nitride growth by metalorganic chemical vapor deposition (MOCVD). This layer is being used to prevent Zn diffusion from the substrate, protect the ZnO surface from H2 back etching, and promote high quality nitride growth. ALD-Al2O3 films were grown at 100°C and then annealed in a furnace at various times at 1100°C for crystallization of the passivation layer. XRD results showed both Al2O3 and ZnAl2O4 phases at different intensities for 50 and 20nm ALD-AlM2O3 films. In addition, the InGaN layer has been successfully grown on the passivated ZnO substrate. Findings show that a short annealing time for the ALD-Al2O3 layer will be optimal for InGaN growth.
Dilute magnetic semiconductors (DMS) show promise as materials that can exhibit ferromagnetism at room temperature (RT). However, the nature of ferromagnetism in this material system must be well understood in order to allow intelligent design of RT spintronic devices. This work investigates the magnetic properties of the as-grown films and the effect of Mn incorporation on crystal integrity and device performance. Ga1-xMnxN films were grown by MOCVD on c-plane sapphire substrates with varying thickness and Mn concentration. Homogenous Mn incorporation throughout the films was verified with Secondary Ion Mass
Spectroscopy (SIMS), and no macroscopic second phases (MnxNy) were detected using X-ray diffraction (XRD). Superior crystalline quality in the MOCVD-grown films relative to Mn-implanted GaN epilayers was confirmed via Raman spectroscopy. Vibrating sample magnetometry measurements showed an apparent room temperature ferromagnetic hysteresis in the as-grown epiayers. Similarly, a marked decrease in the magnetization was observed with annealing and silicon doping, as well as in post-growth annealed Mg-codoped samples. The observed decrease in muB per Mn with increasing Mn concentration is explained by Raman spectroscopy results, which show a decrease in long-range lattice ordering and an increase in nitrogen vacancy concentration with increasing Mn concentration. Magnetic and electron-spin paramagnetic resonance (EPR) data also show that the position of the Fermi level relative to the Mn2+/3+ level is the determining factor in magnetization. Light emitting diodes (LEDs) containing a Mn-doped active region have also been produced. Devices were fabricated with different Mn-doped active layer thicknesses, and I-V characteristics show that the devices become more resistive as thickness of the Mn-doped active layer increases. The magnetic and structural properties observed in this work will be used in conjunction with characteristics and magneto-optical of the Mn-containing devices to discuss the theoretical models of ferromagnetism in Ga1-xMnxN
The developments of two major components of a three terminal dual wavelength LED for excitation of multiple phosphors are described. Such a configuration will be novel Broadband Spectrally Dynamic Light Emitting Diode (BSDLED). First, work towards a functional tunnel junction in the GaN system is discussed. The developments of p+ and n+ GaN layers are specifically discussed in relation to their use in a buried current spreading contact layer. Second, the analysis of several phosphors and their application in a spectrally dynamic source is explored. The response to multiple wavelengths of the phosphors is analyzed to create a light source that can be tuned in “real time” to a wide range of correlated color temperatures.
The incorporation of Mn into GaMnN epilayers by MOCVD growth was investigated. Samples with high Mn concentrations lead to room temperature ferromagnetism. In addition an absorption band around 1.5 eV was observed. Intensity and linewidth of this band scaled with the Mn concentration and with the room temperature (RT) saturation magnetization. This band is assigned to the internal Mn3+ transition between the 5E and the partially filled 5T2 levels of the 5D state. The broadening of the absorption band is introduced by the high Mn concentration. Recharging of the Mn3+ to Mn2+ was found to effectively suppress these transitions resulting also in a significant reduction of the RT magnetization. The pronounced sensitivity of the relative position of the Fermi level and 1.5 eV absorption band can be used to predict the magnetization behavior of the Ga1−xMnxN epilayers. The absence of doping-induced strain was observed by Raman spectroscopy. The structural quality, the presence of Mn2+ ions were confirmed by EPR spectroscopy, meanwhile no Mn-Mn interactions were observed.
This paper reports the impact of the Mn incorporation on the structural and magnetic properties of Ga1−xMnxN on the metal-organic vapor phase deposition (MOCVD). Crystalline quality and phase purity were determined by high-resolution X-ray diffraction and indicated that no macroscopic second phases are formed during growth. Atomic force microscopy revealed a 2-dimensional MOCVD step-flow growth pattern in the Mn-incorporated samples. Various annealing steps were applied to some of the samples to reduce compensating defects and to investigate the effects of post processing on the growth. SQUID measurements showed an apparent ferromagnetic hysteresis behavior. However, none of the requirements for room temperature ferromagnetism in the prevailing mean field DMS theories were found. Therefore, different origins of the ferromagnetic signal are discussed.
We report a technique for the formation of infiltrated and inverse opal structures that produces high quality, low porosity conformal material structures. ZnS:Mn and TiO2 were deposited within the void space of an opal lattice by atomic layer deposition. The resulting structures were etched with HF to remove the silica opal template. Infiltrated and inverse opals were characterized by SEM, XRD, and transmission/reflection spectroscopy. The reflectance spectra exhibited features corresponding to strong low and high order photonic band gaps in the (111) direction (γ-L). In addition, deliberate partial infiltrations and multi-layered inverse opals have been formed. The effectiveness of a post-deposition heat treatment for converting TiO2 films to rutile was also studied.
A forced hydrolysis technique is used for preparing Y2O3: Eu3+ powders at low processing temperatures. The technique uses yttrium oxide, europium oxide, and nitric acid and urea, and has the potential for large-scale production for industrial applications. Several experimental conditions have been examined to optimize the luminescence efficiency. The best result was found to be at 2 mol% Eu doping and a 2 h firing of 1400 °C. Microstructural information provided by x-ray diffraction, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) have been applied to interpret the observed luminescent properties.
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