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The use of peritoneal catheters for prophylactic dialysis or drainage to prevent fluid overload after neonatal cardiac surgery is common in some centres; however, the multi-centre variability and details of peritoneal catheter use are not well described.
Methods:
Twenty-two-centre NEonatal and Pediatric Heart Renal Outcomes Network (NEPHRON) study to describe multi-centre peritoneal catheter use after STAT category 3–5 neonatal cardiac surgery using cardiopulmonary bypass. Patient characteristics and acute kidney injury/fluid outcomes for six post-operative days are described among three cohorts: peritoneal catheter with dialysis, peritoneal catheter with passive drainage, and no peritoneal catheter.
Results:
Of 1490 neonates, 471 (32%) had an intraoperative peritoneal catheter placed; 177 (12%) received prophylactic dialysis and 294 (20%) received passive drainage. Sixteen (73%) centres used peritoneal catheter at some frequency, including six centres in >50% of neonates. Four centres utilised prophylactic peritoneal dialysis. Time to post-operative dialysis initiation was 3 hours [1, 5] with the duration of 56 hours [37, 90]; passive drainage cohort drained for 92 hours [64, 163]. Peritoneal catheter were more common among patients receiving pre-operative mechanical ventilation, single ventricle physiology, and higher complexity surgery. There was no association with adverse events. Serum creatinine and daily fluid balance were not clinically different on any post-operative day. Mortality was similar.
Conclusions:
In neonates undergoing complex cardiac surgery, peritoneal catheter use is not rare, with substantial variability among centres. Peritoneal catheters are used more commonly with higher surgical complexity. Adverse event rates, including mortality, are not different with peritoneal catheter use. Fluid overload and creatinine-based acute kidney injury rates are not different in peritoneal catheter cohorts.
Obesity is highly prevalent and disabling, especially in individuals with severe mental illness including bipolar disorders (BD). The brain is a target organ for both obesity and BD. Yet, we do not understand how cortical brain alterations in BD and obesity interact.
Methods:
We obtained body mass index (BMI) and MRI-derived regional cortical thickness, surface area from 1231 BD and 1601 control individuals from 13 countries within the ENIGMA-BD Working Group. We jointly modeled the statistical effects of BD and BMI on brain structure using mixed effects and tested for interaction and mediation. We also investigated the impact of medications on the BMI-related associations.
Results:
BMI and BD additively impacted the structure of many of the same brain regions. Both BMI and BD were negatively associated with cortical thickness, but not surface area. In most regions the number of jointly used psychiatric medication classes remained associated with lower cortical thickness when controlling for BMI. In a single region, fusiform gyrus, about a third of the negative association between number of jointly used psychiatric medications and cortical thickness was mediated by association between the number of medications and higher BMI.
Conclusions:
We confirmed consistent associations between higher BMI and lower cortical thickness, but not surface area, across the cerebral mantle, in regions which were also associated with BD. Higher BMI in people with BD indicated more pronounced brain alterations. BMI is important for understanding the neuroanatomical changes in BD and the effects of psychiatric medications on the brain.
Alcohol use disorder (AUD) and schizophrenia (SCZ) frequently co-occur, and large-scale genome-wide association studies (GWAS) have identified significant genetic correlations between these disorders.
Methods
We used the largest published GWAS for AUD (total cases = 77 822) and SCZ (total cases = 46 827) to identify genetic variants that influence both disorders (with either the same or opposite direction of effect) and those that are disorder specific.
Results
We identified 55 independent genome-wide significant single nucleotide polymorphisms with the same direction of effect on AUD and SCZ, 8 with robust effects in opposite directions, and 98 with disorder-specific effects. We also found evidence for 12 genes whose pleiotropic associations with AUD and SCZ are consistent with mediation via gene expression in the prefrontal cortex. The genetic covariance between AUD and SCZ was concentrated in genomic regions functional in brain tissues (p = 0.001).
Conclusions
Our findings provide further evidence that SCZ shares meaningful genetic overlap with AUD.
Introduction: Simulation has assumed an integral role in the Canadian healthcare system with applications in quality improvement, systems development, and medical education. High quality simulation-based research (SBR) is required to ensure the effective and efficient use of this tool. This study sought to establish national SBR priorities and describe the barriers and facilitators of SBR in Emergency Medicine (EM) in Canada. Methods: Simulation leads (SLs) from all fourteen Canadian Departments or Divisions of EM associated with an adult FRCP-EM training program were invited to participate in three surveys and a final consensus meeting. The first survey documented active EM SBR projects. Rounds two and three established and ranked priorities for SBR and identified the perceived barriers and facilitators to SBR at each site. Surveys were completed by SLs at each participating institution, and priority research themes were reviewed by senior faculty for broad input and review. Results: Twenty SLs representing all 14 invited institutions participated in all three rounds of the study. 60 active SBR projects were identified, an average of 4.3 per institution (range 0-17). 49 priorities for SBR in Canada were defined and summarized into seven priority research themes. An additional theme was identified by the senior reviewing faculty. 41 barriers and 34 facilitators of SBR were identified and grouped by theme. Fourteen SLs representing 12 institutions attended the consensus meeting and vetted the final list of eight priority research themes for SBR in Canada: simulation in CBME, simulation for interdisciplinary and inter-professional learning, simulation for summative assessment, simulation for continuing professional development, national curricular development, best practices in simulation-based education, simulation-based education outcomes, and simulation as an investigative methodology. Conclusion: Conclusion: This study has summarized the current SBR activity in EM in Canada, as well as its perceived barriers and facilitators. We also provide a consensus on priority research themes in SBR in EM from the perspective of Canadian simulation leaders. This group of SLs has formed a national simulation-based research group which aims to address these identified priorities with multicenter collaborative studies.
We ask if Earth-like planets (terrestrial mass and habitable-zone orbit) can be detected in multi-planet systems, using astrometric and radial velocity observations. We report here the preliminary results of double-blind calculations designed to answer this question.
Soft x-ray scanning transmission x-ray microscope (STXM) spectromicroscopy has been developed and employed to investigate several aspects of actinide chemistry and materials science at the Advanced Light Source Molecular Environmental Science (ALS-MES) Beamline 11.0.2 STXM end station. The basic approach and fundamentals of STXM experiments for radioactive materials systems is discussed. Representative results from STXM spectromicroscopy investigations of a mixed phase uranium nitride, single crystals of Eu(III)[TREN(Me-3,2-HOPO)]3 2H2O and hydrated Pu2(III)(C2O4)3(6H2O) 3H2O complexes are presented. The STXM images and soft x-ray absorption spectra illustrate the capabilities and utility of soft x-ray STXM for providing information about actinide materials, especially the light element constituents. Lastly, new and future opportunities for actinide science utilizing soft x-ray STXM are discussed in light of the planned upgrades for the STXM end stations at the ALS.
The deposition and post-treatment processes involved in the production of porous organosilicate glasses (OSGs) by plasma-enhanced chemical vapor deposition (PECVD) with ultraviolet light (UV) treatment are investigated through the use of a deuterated organic porogen precursor using infrared spectroscopy and solid-state nuclear magnetic resonance spectroscopy. Infrared analysis provides evidence for hydrogen-deuterium scrambling between the chemical species during the deposition process, which is exacerbated by the UV treatment process. Analysis of 13C cross-polarized magic angle spinning (CP-MAS) NMR suggests that the porogen exists in domains relatively isolated from the network, in agreement with short UV treatment time morphological data that indicates the pore size is relatively constant from the early stages of UV treatment process. The chemical and morphological information provides further support for a deposition controlled morphology and has implications towards enhanced chemical processing of porous organosilicate glass (OSG) films for back-end-of-line integrated circuit manufacturing.
Fabrication of air gap features have been achieved by three processes utilizing the diffusion of materials through a porous OSG layer. The first process involves the decomposition of a PECVD deposited organic material, either thermally or via UV anneal, to create a void with the decomposition by-products diffusing through the porous OSG layer. The second process uses the etch selectivity of XeF2 or BrF3 towards silicon versus OSG to diffuse through the porous OSG layer to etch the underlying silicon. Finally the water solubility of films such as GeO2 or B2O3, which can be easily deposited by PECVD, can be utilized for void formation via dissolution of the sacrificial inorganic layer through the porous OSG.
Porous organosilicate materials produced by plasma enhanced chemical vapor deposition are the leading candidates for back-end-of-line dielectric insulators for IC manufacturing at 45nm design features and beyond. The properties of porous organosilicate glass films of dielectric constant k=2.50 ± 0.05 formed using diethoxymethylsilane and five different porogen precursors with an ultraviolet post treatment are reported. By varying the porogen precursor type pore sizes of 1-2 nm (equivalent spherical diameter) and porosities in the range of 24-31% were measured. While there were no observable trends in pore size with the molecular volume or plasma reactivity of the porogen precursor, modulus values ranged from 6.6 to 10.8 GPa. Porous films with the highest mechanical properties were found to have the highest matrix dielectric constant, highest network connectivity (lowest methyl content), and highest density. Within this process space, maximizing the network connectivity of the film was found to be more important to mechanical properties than lowering the total porosity. In effect, the choice of porogen precursor dictates the film morphology through its impact on the organosilicate glass matrix and pore size.
New ligands and materials are required that can coordinate, sense, and purify actinides for selective extraction and reduction of toxic, radioactive wastes from the mining and purification of actinides. The similarities in the chemical, biological transport, and distribution properties of Fe(III) and Pu(IV) inspired a biomimetic approach to the development of sequestering agents for actinides. A detailed evaluation of the structure and bonding of actinide coordinating ligands like these is important for the design of new selective ligand systems. Knowing the difficulty with working with the crystals resulting from these ligand systems and safe handling considerations for working with Pu, procedures were developed that utilize the Advanced Light Source of Lawrence Berkeley National Laboratory to determine the solid-state structures of Pu complexes by X-ray diffraction.
From a 45ks Chandra observation of V42G Oph we have obtained high-resolution X-ray spectra at moderate signal-to-noise, and a, good quality, uninterrupted lightcurve. The spectra are reasonably fit with a cooling flow model, similar to EX Hya and U Gem. Our analysis of the Chandra and additional X-ray/optical lightcurves reveals a persistent modulation at 4.2 hr from 1988 to 2003, likely the white dwarf spin period indicating an intermediate polar nature for V426 Oph.
We report on our work to develop a process for depositing nanoporous organosilicate (OSG) films via plasma enhanced chemical vapor deposition (PECVD). This approach entails codepositing an OSG material with a plasma polymerizable hydrocarbon, followed by thermal annealing of the material to remove the porogen, leaving an OSG matrix with nano-sized voids. The dielectric constant of the final film is controlled by varying the ratio of porogen precursor to OSG precursor in the delivery gas. Because of the need to maintain the mechanical strength of the final material, diethoxymethylsilane (DEMS) is utilized as the OSG precursor. Utilizing this route we are able to deposit films with a dielectric constant of 2.55 to 2.20 and hardness of 0.7 to 0.3 GPa, respectively.
The effectiveness of influenza vaccination in reducing hospitalization of people with diabetes for influenza, pneumonia, or diabetic events during influenza epidemics was assessed in a case control study in Leicestershire, England. Cases were 80 patients on the Leicestershire Diabetes Register who were admitted and discharged from hospital with International Classification of Disease codes for pneumonia, bronchitis, influenza, diabetic ketoacidosis, coma and diabetes, without mention of complications, during the influenza epidemics of 1989–90 and 1993. One hundred and sixty-controls, who were not admitted to hospital during this period, were randomly selected from the Register. Immunization against influenza was assessed in 37 cases and 77 controls for whom consent was obtained to access their clinical notes and for whom notes were available. Significant association was detected between reduction in hospitalization and influenza vaccination during the period immediately preceding an epidemic. Multiple logistic regression analysis estimated that influenza vaccination reduced hospital admissions by 79% (95% CI 19–95%) during the two epidemics, after adjustment for potential confounders.