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To evaluate the association between novel pre- and post-operative biomarker levels and 30-day unplanned readmission or mortality after paediatric congenital heart surgery.
Children aged 18 years or younger undergoing congenital heart surgery (n = 162) at Johns Hopkins Hospital from 2010 to 2014 were enrolled in the prospective cohort. Collected novel pre- and post-operative biomarkers include soluble suppression of tumorgenicity 2, galectin-3, N-terminal prohormone of brain natriuretic peptide, and glial fibrillary acidic protein. A model based on clinical variables from the Society of Thoracic Surgery database was developed and evaluated against two augmented models.
Unplanned readmission or mortality within 30 days of cardiac surgery occurred among 21 (13%) children. The clinical model augmented with pre-operative biomarkers demonstrated a statistically significant improvement over the clinical model alone with a receiver-operating characteristics curve of 0.754 (95% confidence interval: 0.65–0.86) compared to 0.617 (95% confidence interval: 0.47–0.76; p-value: 0.012). The clinical model augmented with pre- and post-operative biomarkers demonstrated a significant improvement over the clinical model alone, with a receiver-operating characteristics curve of 0.802 (95% confidence interval: 0.72–0.89; p-value: 0.003).
Novel biomarkers add significant predictive value when assessing the likelihood of unplanned readmission or mortality after paediatric congenital heart surgery. Further exploration of the utility of these novel biomarkers during the pre- or post-operative period to identify early risk of mortality or readmission will aid in determining the clinical utility and application of these biomarkers into routine risk assessment.
Introduction: The harm that may come to healthcare providers impacted by adverse events has led them to be called “second victims.” Our objective was to characterize the range and context of interventions used to support second victims in acute care settings. Methods: We performed a scoping study using the process described by Arksey and O'Malley. Comprehensive searches of scientific databases and grey literature were conducted in September 2017 and updated in November 2018. A library scientist searched PubMed, CINAHL, EMBASE and CENTRAL. We sought unpublished literature (Canadian Electronic Library, Proquest and Scopus) and searched reference lists of included studies. Stakeholder organizations and authors of included studies were contacted through email, requesting information on relevant programs. Two reviewers independently reviewed titles and abstracts using predetermined criteria. Using a structured data abstraction form, two reviewers independently extracted data and appraised methodological quality with the Mixed Methods Appraisal Tool (MMAT). All discrepancies were resolved through consensus. A qualitative approach was used to categorize the context and characteristics of the identified strategies and interventions. Results: Our search strategy yielded 3883 results. After screening titles and abstracts, 173 studies underwent full text screening. Extracted data reflected 21 interventions categorized as providing peer-support (n = 7), proactive education (n = 7) or both (n = 7). Programs came from Canada (n = 2), Spain (n = 2), and United States (n = 17). Specific traumatic events were described as the trigger for development of five programs. While some programs were confined to a standard definition of second victim as a healthcare provider traumatized by an “unanticipated adverse patient event” (n = 6), other programs had a broader scope (n = 12) including situations such as non-accidental trauma, stressful anticipated patient events and complaints/litigation (3 programs were unclear about the definition). Confidentiality was assured in nine peer support programs. Outcome measures were often not reported and were limited in terms of quality. Conclusion: This is a new area of study with little scientific rigour from which to determine whether these programs are effective. Concerns about protecting healthcare providers from potential legal proceedings hinder documentation and study of program effectiveness.
The triazines are one of the most widely used herbicide classes ever developed and are critical for managing weed populations that have developed herbicide resistance. These herbicides are traditionally valued for their residual weed control in more than 50 crops. Scientific literature suggests that atrazine, and perhaps other s-triazines, may no longer remain persistent in soils due to enhanced microbial degradation. Experiments examined the rate of degradation of atrazine and two other triazine herbicides, simazine and metribuzin, in both atrazine-adapted and non-history Corn Belt soils, with similar soils being used from each state as a comparison of potential triazine degradation. In three soils with no history of atrazine use, the t1/2 of atrazine was at least four times greater than in three soils with a history of atrazine use. Simazine degradation in the same three sets of soils was 2.4 to 15 times more rapid in history soils than non-history soils. Metribuzin in history soils degraded at 0.6, 0.9, and 1.9 times the rate seen in the same three non-history soils. These results indicate enhanced degradation of the symmetrical triazine simazine, but not of the asymmetrical triazine metribuzin.
In view of the broad range of topics covered by Commission U8 and the consequent inevitable overlap with other commissions, it/is not feasible to produce a comprehensive self-contained report. The commission therefore restricts its report to a selected list of accessible recent review articles and conference reports, wherein up-todate summaries of various topics can be found. Such a list is given below. A special report by I. S. Shklovsky on work done in the Soviet Union follows.
Antimicrobial stewardship programs are increasingly recognized as critical in optimizing the use of antimicrobials. Consequently, more physicians, pharmacists, and other healthcare providers are developing and implementing such programs in a variety of healthcare settings. The purpose of this guidance document is to outline the knowledge and skills that are needed to lead an antimicrobial stewardship program. It was developed by antimicrobial stewardship experts from organizations that are engaged in advancing the field of antimicrobial stewardship.
Infect Control Hosp Epidemiol 2014;35(12):1444–1451
Background: Research suggests that core schemas are important in both the development and maintenance of psychosis. Aims: The aim of the study was to investigate and compare core schemas in four groups along the continuum of psychosis and examine the relationships between schemas and positive psychotic symptomatology. Method: A measure of core schemas was distributed to 20 individuals experiencing first-episode psychosis (FEP), 113 individuals with “at risk mental states” (ARMS), 28 participants forming a help-seeking clinical group (HSC), and 30 non-help-seeking individuals who endorse some psychotic-like experiences (NH). Results: The clinical groups scored significantly higher than the NH group for negative beliefs about self and about others. No significant effects of group on positive beliefs about others were found. For positive beliefs about the self, the NH group scored significantly higher than the clinical groups. Furthermore, negative beliefs about self and others were related to positive psychotic symptomatology and to distress related to those experiences. Conclusions: Negative evaluations of the self and others appear to be characteristic of the appraisals of people seeking help for psychosis and psychosis-like experiences. The results support the literature that suggests that self-esteem should be a target for intervention. Future research would benefit from including comparison groups of people experiencing chronic psychosis and people who do not have any psychotic-like experiences.
We present herein recent findings of an investigation of catalyst assembly and activation using metallic nanoparticles encapsulated with organic monolayers. Gold nanocrystals (2∼5 nm) encapsulated with thiolate monolayers assembled on electrode surfaces, were found to be catalytically active towards electrooxidation of CO and MeOH upon activation. The activation involved partial removal of the encapsulating thiolates and the formation of surface oxygenated species. A polymeric film was also used as a substrate for the assembly of the nanoparticle catalysts. When the polymer matrix was doped with small amounts of Pt, a remarkable catalytic activity was observed. These catalysts were characterized utilizing cyclic voltammetry and atomic force microscopy.
Noble gases are generally very insoluble in solids. For example, Xe implanted into Al at 300 K forms a fine dispersion of crystalline precipitates and, at large enough fluence, fluid precipitates, both of which are stabilized, relative to the gas phase, by the Laplace pressure due to precipitate/matrix interface tensions. High resolution electron microscopy has been performed to determine the largest Xe nanocrystalline precipitate in local equilibrium with fluid Xe precipitates within the Al matrix. From the shape and size of the largest crystal and the Laplace pressure associated with its interface, we show that the interface tensions can be derived by setting the Laplace pressure equal to the pressure for solid/fluid Xe equilibrium derived from bulk Xe compression isotherms at the temperature of equilibration and observation. The Xe/Al interface tensions thus derived are in the range of accepted values of surface tensions for the Al matrix. Furthermore, it is suggested that this same technique may be employed to estimate unknown surface tensions of a solid matrix from the size and shape of maximal nanocrystals of a noble gas element, which have been equilibrated in that matrix at the temperature of observation.
The role of the neutral dangling bond defect upon photocarrier processes in undoped amorphous hydrogenated silicon (a-Si:H) is discussed. The evidence that the dangling bond is a simple recombination center is reviewed, and it is shown that this model does not account for photocurrent response time measurements. Experimental data pertinent to the role of electrical contacts upon response time measurements are presented, and it is concluded that contact effects do not account for response-time measurements. The possibility that the dangling bond is primarily an electron trap is discussed.
Drift-mobility measurements in undoped amorphous hydrogenated silicon (a-Si:H) are reviewed with emphasis on the effects of deep levels (principally the D or dangling bond defect) on the electron drift mobility. An outline of several techniques for measuring drift mobilities is also given to establish their relationships to the transient drift-mobility function. µ(t). Three aspects of the electron µ(t) in undoped a-Si:H are described in detail: (i) anisotropy at long times, requiring a distinction between axial electric fields (parallel to the growth axis) and planar fields normal to it, (ii) the D center deep-trapping cutoff observed in the axial µ(t), and (iii) D center multiple-trapping at long times in the planar drift-mobility. Microstructure effects which might account for the electron drift-mobility are discussed.
We have investigated magneto-transport properties of differently strained Si/ Si1−xGex resonant tunneling devices. The built-in strain was either put in the Si layers, by means of a thick., relaxed Si1−xGex buffer layer, or in the Si1−xGex layers, in which case all Si1−xGex layers were grown below the critical thickness, and a Si1−xGex spacer layer with graded Ge content was used. Magnetic fields parallel to the interface have been employed to probe the in-plane dispersion in the quantum well. This is used to study the effect of band-mixing in the two strain configurations. A field perpendicular to the interface resolves some Landau level splitting. Most strikingly, however, is the similarity in the spectra with the case when the magnetic field is applied parallel to the interfaces. This indicates broadening of the levels, possibly due to scattering, and the importance of 3-dimensional band structure effects.
We report the growth and characterization of GexSi1−x films for optical waveguiding. GexSi1−x/Si waveguides were grown by rapid thermal processing chemical vapor deposition. An average attenuation of 3.3 dB/cm was achieved for a 1 μm thick Ge0.04Si0.96 layer patterned into rib waveguides 2000 Å deep with widths of 5 μm. Directional couplers were also fabricated. Average coupling efficiencies of 85% were achieved for 1.5 μm interwaveguide separation.
Interface mixing between the Ge and Si layers in symmetrically strained SimGem superlattices occurs during post growth thermal anneals. Interdiffusion coefficients were obtained from intensity changes in the low angle superlattice x-ray satellites on samples with nominal periodicities between 1.4nm and 5.6nm. A common activation energy of 3.0±0.1 eV was found. The bulk interdiffusion coefficients for SimGem were derived since measurements were made on samples with different layer thicknesses. Intermixing appears to occur by diffusion of Si atoms into the Ge layers via a vacancy mechanism. Raman scattering measurements support this process as well as the formation of Si1−xGex, alloy layers during the anneals.
The thermal oxidation of epitaxial Ge.36Si.64 on (100)Si is investigated experimentally for a wet ambient at 700°C and 1000°C. A pure silicon dioxide layer with pile-up of Ge behind the oxide is formed at 1000°C. At 700°C, however, both Ge and Si are oxidized. The Ge is included uniformly into the oxide layer without changing the initial Ge/Si ratio. The result at 1000°C follows the thermodynamical picture which predicts the same result at 700°C also, contrary to observation. The different result at 700°C is due to kinetic constraints which can be explained by different activation energies for the rate of the oxidation reaction and for the Ge or Si diffusivities in GeSi.