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We evaluated provider adherence to practice guidelines for inpatients diagnosed with Clostridoides difficile infection (CDI) before and after implementation of a best practice alert (BPA) linking a positive test result to guideline-based orders. After implementation of the BPA, guideline-based prescribing increased from 39.4% in 2013 to 67.7% in 2016 (P = .014).
Our understanding of the complex relationship between schizophrenia symptomatology and etiological factors can be improved by studying brain-based correlates of schizophrenia. Research showed that impairments in value processing and executive functioning, which have been associated with prefrontal brain areas [particularly the medial orbitofrontal cortex (MOFC)], are linked to negative symptoms. Here we tested the hypothesis that MOFC thickness is associated with negative symptom severity.
This study included 1985 individuals with schizophrenia from 17 research groups around the world contributing to the ENIGMA Schizophrenia Working Group. Cortical thickness values were obtained from T1-weighted structural brain scans using FreeSurfer. A meta-analysis across sites was conducted over effect sizes from a model predicting cortical thickness by negative symptom score (harmonized Scale for the Assessment of Negative Symptoms or Positive and Negative Syndrome Scale scores).
Meta-analytical results showed that left, but not right, MOFC thickness was significantly associated with negative symptom severity (βstd = −0.075; p = 0.019) after accounting for age, gender, and site. This effect remained significant (p = 0.036) in a model including overall illness severity. Covarying for duration of illness, age of onset, antipsychotic medication or handedness weakened the association of negative symptoms with left MOFC thickness. As part of a secondary analysis including 10 other prefrontal regions further associations in the left lateral orbitofrontal gyrus and pars opercularis emerged.
Using an unusually large cohort and a meta-analytical approach, our findings point towards a link between prefrontal thinning and negative symptom severity in schizophrenia. This finding provides further insight into the relationship between structural brain abnormalities and negative symptoms in schizophrenia.
Recent commentary has suggested that performance management (PM) is fundamentally “broken,” with negative feelings from managers and employees toward the process at an all-time high (Pulakos, Hanson, Arad, & Moye, 2015; Pulakos & O'Leary, 2011). In response, some high-profile organizations have decided to eliminate performance ratings altogether as a solution to the growing disenchantment. Adler et al. (2016) offer arguments both in support of and against eliminating performance ratings in organizations. Although both sides of the debate in the focal article make some strong arguments both for and against utilizing performance ratings in organizations, we believe there continue to be misunderstandings, mischaracterizations, and misinformation with respect to some of the measurement issues in PM. We offer the following commentary not to persuade readers to adopt one particular side over another but as a call to critically reconsider and reevaluate some of the assumptions underlying measurement issues in PM and to dispel some of the pervasive beliefs throughout the performance rating literature.
We report apparent robust doping of ZnO and MgxZn1-xO (x ∼20%) nanoparticle films by annealing in hydrogen gas. The annealing was done at sequentially higher temperatures from about 20 °C to 140 °C. The effect of the annealing was determined by comparing current-voltage measurements of the samples at room-temperature and in vacuum after each annealing cycle.The nanoparticles were grown using an aqueous solution and heating process that created thinfilms of ZnO or MgZnO nanoparticles with diameters of about 30 nm. When exposed to hydrogen gas at room-temperature or after annealing at temperatures up to about 100 °C, no measureable changes to the room-temperature vacuum conductivity of the films was observed. However, when the samples were annealed at temperatures above 100 °C, an appreciable robust increase in the room-temperature conductance in vacuum occurred. Annealing at the maximum temperature (∼135-140 °C) resulted in about a factor of about twenty increase in the conductivity. Furthermore, the ratio of the conductance of the ZnO and MgZnO nanoparticle films while being annealed to their conductance at room-temperature were found to increase and then decrease for increasing annealing temperatures. Maximum changes of about five-fold and seven-fold for the MgZnO and ZnO samples, respectively, were found to occur at temperatures just below the annealing temperature threshold for the onset of the robust hydrogen gas doping. Comparisons of these results to other work on bulk ZnO and MgZnO films and reasons for this behavior will be discussed.
Bandgap engineered ZnSxO1-x films were grown on Fluorinated Ethylene Propylene (FEP) substrates and analyzed using transmission spectroscopy. FEP is considered as a potential substrate for application in flexible electronics and semiconductor films.
In January 2009, the IAEA EMRAS II (Environmental Modelling for Radiation Safety II) program was launched. The goal of the program is to develop, compare and test models for the assessment of radiological impacts to the public and the environment due to radionuclides being released or already existing in the environment; to help countries build and harmonize their capabilities; and to model the movement of radionuclides in the environment. Within EMRAS II, nine working groups are active; this paper will focus on the activities of Working Group 1: Reference Methodologies for Controlling Discharges of Routine Releases. Within this working group environmental transfer and dose assessment models are tested under different scenarios by participating countries and the results compared. This process allows each participating country to identify characteristics of their models that need to be refined. The goal of this working group is to identify reference methodologies for the assessment of exposures to the public due to routine discharges of radionuclides to the terrestrial and aquatic environments. Several different models are being applied to estimate the transfer of radionuclides in the environment for various scenarios. The first phase of the project involves a scenario of nuclear power reactor with a coastal location which routinely (continuously) discharges 60Co, 85Kr, 131I, and 137Cs to the atmosphere and 60Co, 137Cs, and 90Sr to the marine environment. In this scenario many of the parameters and characteristics of the representative group were given to the modellers and cannot be altered. Various models have been used by the different participants in this inter-comparison (PC-CREAM, CROM, IMPACT, CLRP POSEIDON, SYMBIOSE and others). This first scenario is to enable a comparison of the radionuclide transport and dose modelling. These scenarios will facilitate the development of reference methodologies for controlled discharges.
Four Class I maser sources were detected at 44, 84, and 95 GHz toward chemically rich outflows in the regions of low-mass star formation NGC 1333I4A, NGC 1333I2A, HH25, and L1157. One more maser was found at 36 GHz toward a similar outflow, NGC 2023. Flux densities of the newly detected masers are no more than 18 Jy, being much lower than those of strong masers in regions of high-mass star formation. The brightness temperatures of the strongest peaks in NGC 1333I4A, HH25, and L1157 at 44 GHz are higher than 2000 K, whereas that of the peak in NGC 1333I2A is only 176 K. However, a rotational diagram analysis showed that the latter source is also a maser. The main properties of the newly detected masers are similar to those of Class I methanol masers in regions of massive star formation. The former masers are likely to be an extension of the latter maser population toward low luminosities of both the masers and the corresponding YSOs.
While zinc oxide is a promising material for blue and UV solid-state lighting devices, the lack of p-type doping has prevented ZnO from becoming a dominant material for optoelectronic applications. Over the past decade, numerous reports have claimed that nitrogen is a viable p-type dopant in ZnO. However, recent calculations by Lyons, Janotti, and Van de Walle [Appl. Phys. Lett. 95, 252105 (2009)] suggest that nitrogen is a deep acceptor. In our work, we performed photoluminescence (PL) measurements on bulk, single crystal ZnO grown by chemical vapor transport. Nitrogen doping was achieved by growing in ammonia. In prior work at room temperature, we observed a broad PL band at ∼1.7 eV, with an excitation threshold of ∼2.2 eV, consistent with the calculated configuration-coordinate diagram. In the present work, at liquid-helium temperatures, the PL emission increases in intensity and red-shifts by ∼0.2 eV. A peak is observed at 3.267 eV, which we tentatively attribute to an exciton bound to a nitrogen acceptor. Our experimental results indicate that nitrogen is indeed a deep acceptor and cannot be used to produce p-type ZnO.
We report an adolescent with a benign cardiac haemangioma with attachments exclusively to the anterior leaflet of the mitral valve. On the basis of our review of the literature, this study has not been reported previously.
The enthalpy of melting and the heat capacity of liquid zirconolite (CaZrTi2O7) are estimated as equal to 200 ± 20 kJ·dmol−1 and 350 ± 50 J·mol−1·K−1, respectively. Thermodynamic functions of solid and liquid zirconolite are calculated based on these estimated data and the results of Navrotsky et al. On the basis of these thermodynamic functions, computational thermodynamic simulation is performed on the thermochemical synthesis of zirconolite-bearing materials. Demonstration indicates that synthesis of zirconolite-like matrix materials is possible using the self-sustaining exothermic reaction.
Nanoparticles of ZnO were synthesized using a sonochemical technique. Sonochemistry arises from an acoustic cavitation phenomenon, that is, the formation, growth and implosive collapse of bubbles in a liquid medium. The ultraviolet photoluminescence (PL) studies of the samples showed a strong PL intensity and a significant blue shift relative to the PL of the bulk. Shifts up to 70 meV were observed and attributed to a confinement effect. Scanning electron microscopy indicated roughly spherical particles, ∼160 nm in diameter. However, nano-platelets and rods were observed in transmission electron micrographs. Preliminary electrical measurements indicated a highly resistive nature of the nanoparticulate material.
Hardness properties of CVD SiO2, films deposited on silicon substrates are investigated by microindentation techniques. It is found that the hardness of these films is sensitive to the thermal histories and doping and is less influenced by the residual stress levels.
Micro- and Macro-photoluminescence techniques were employed in this research to investigate the role of nitrogen-doping on the optical spectra of chemical vapor deposited diamond films and to determine whether the origin of the broadband luminescence is due to vibronic interaction of the nitrogen centers. The temperature behavior of the broadband PL and of the 1.681 eV silicon related optical center were analyzed. The intensity of the broadband was found to exhibit a temperature dependence characteristic of optical emission from a continuous distribution of gap states while the temperature dependence of the 1.681 eV band followed the Boltzmann quenching process.
The system C – Al – TiO2 has been demonstrated to be a strong candidate for the processing of irradiated reactor graphite waste with the retention of biologic hazardous carbon-14 in chemically and thermal stable corundum-carbide ceramics. The corundum-carbide ceramics is obtained from the powdered precursors blend through self-sustaining thermochemical reactions. Investigations of the system C – Al – TiO2 were carried out both theoretically and experimentally. The refining thermodynamic calculations of the phase composition of resulting end product were performed for a wide variety of components content in the system being investigated. Aluminium oxycarbides production was taken into account in the calculations. Thermodynamic functions of aluminium oxycarbides Al4O4C and Al2OC have been calculated for this purpose using currently available literature evidences and own assessments of missing data. On the basis of thermodynamic simulation the proportions of the source substances were determined, which result in the aluminium oxycarbides production. These simulation results have been supported by XRD-analysis of produced specimens. The experimental processing of reactor graphite was conducted by the use of self-sustaining reactions in C – Al – TiO2 powder blends. Test specimens were produced by mass ranging from 0.1 to 3 kg in the argon atmosphere. Various techniques were used to characterize the produced specimens. The compressive strength of specimens of corundum-carbide matrices produced ranges from 7 to 13 MPa. The leaching rates of Cs-137 and Sr-90 from specimens ranged between 10-4 and 10-5 g/(cm2.day) respectively. The carry-over of the carbon combined in carbon monoxide from the reacting mixtures during exothermic process may run up to 1% wt. that appropriates roughly to less than 0.01% wt. of the carbon-14 in the irradiated reactor graphite.
Single crystals of A1N to 1 mm thickness were grown in the range 1950-2250°C on 10×10 mm2 α(6H)-SiC(0001) substrates via sublimation-recondensation method. Hot pressed polycrystalline AlN was used as the source material. The color varied from transparent to dark green/blue. The crystal morphology varied with growth conditions. Most crystals were 0.3 mm -1 mm thick transparent layers which completely covered the substrates. Raman, optical and transmission electron microscopy (TEM) results are presented. Single crystals of gallium nitride (GaN) were also grown by subliming powders of this material under an ammonia (NH3) flow. Optical microscopy, Raman and photoluminescence results are shown.
Nitrogen-doped diamond films were prepared for the first time using melamine (C3H6N6) as the nitrogen source. To explore the differences in the films produced with different precursors, nitrogen-doped films were also produced using pure nitrogen gas as the source. Since melamine has a ring structure with pre-existing C-N bonds, the incorporation of nitrogen on substitutional sites of diamond lattice are expected. Relatively large amounts of substitutional nitrogen were successfully doped into diamond without degrading its quality. However, when pure nitrogen gas was used as a doping source, the quality of the diamond was not as high as the sample doped with nitrogen by melamine. Raman spectroscopy, photoluminescence spectroscopy (PL), and field emission measurements were carried out to characterize the samples. Nitrogen-doped diamond samples did not exhibit any significant reduction in turn-on fields. It is suggested that nitrogen doping has only a minor effect on the field emission properties of the diamond films.
Raman analysis of film quality, phonon-plasmon coupling, and phonon-exciton interaction in GaN films with varying Si doping levels is presented. The films exhibit a small stress component ∽0.1 GPa, calculated from the frequency shift of the E2 mode. No correlation between the stress and the doping concentration was found. No forbidden Raman lines were detected in the spectra, implying high quality oriented films. The Raman lineshape of the E2 mode is a Lorentzian with similar linewidths at room temperature and at 10K indicating a homogeneous lifetime broadening mechanism which is not significantly affected by the change in temperature. The linewidth is also independent of Si concentration. The phonon-plasmon mixed frequency modes were calculated to be at ω−.=86 cm−1 and at ω+=741 cm−1 The modes are not present in the spectra and the only effect of the plasmons is a change of the Al(LO) lineshape. Analysis of the A1(LO) line indicated a uniform spatial doping distribution. A resonance effect was observed for the symmetry-allowed A1(LO) mode at T=10K with sub bandgap excitation light. The resonance interaction is consistent with the free exciton model.