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Study of CeO2 and its native defects by density functional theory with repulsive potential
We investigated the native point defects in CeO2 by the density functional (DFT) +U method,
and using a non-linear core-corrected norm-conserving Ce pseudopotential. We find the neutral
oxygen vacancy (VO
0) in CeO2 to have a very low formation energy of only 0.39eV in the Opoor
limit. It is a deep donor with negative U behavior, only stable in its neutral and doubly
positive states. The anion Frenkel defect is found to be the lowest energy disorder defect, with a
formation energy of only 2.08eV per defect site. These low formation energies arise from the
improved transferability of our Ce pseudopotential for its +3 and +4 valence states. The negative
U behavior of VO leads to excellent photo-catalytic behavior, while the low formation energy of
the anion Frenkel defect leads to a superior oxygen storage-and-release capability.All computing facilities and calculation resources receive funding from the Research Grant
Council, University Grants Committee of the HKSAR government. BH would like to thank the
fund support and calculations resources all supplied by the Department of Physics and Materials
Science, City University of Hong Kong.This is the accepted manuscript. The final version is available from ACS at http://pubs.acs.org/doi/abs/10.1021/jp506625h, under the title 'Study of CeO2 and Its Native Defects by Density Functional Theory with Repulsive Potential'
An Alternative Perspective on Consensus Priors with Applications to Phase I Clinical Trials
We occasionally need to make a decision or a series of decisions based on a small sample. In some cases, an investigator is knowledgeable about a parameter of interest in some degrees or is accessible to various sources of prior information. Yet, two or more experts cannot have an identical prior distribution for the parameter. In this manuscript, we discuss the use of a consensus prior and compare two classes of Bayes estimators. In the first class of Bayes estimators, the contribution of each prior opinion is determined by observing data. In the second class, the contribution of each prior opinion is determined after observing data. Bayesian designs for Phase I clinical trials allocate trial participants at new experimental doses based on accumulated information, while the typical sample sizes are fairly small. Using simulations, we illustrate the usefulness of a combined estimate in the early phase clinical trials
Performance of formulae based estimates of glomerular filtration rate for carboplatin dosing in stage 1 seminoma
<b>Background:</b> Single cycle carboplatin, dosed by glomerular filtration rate (GFR), is standard adjuvant therapy for stage 1 seminoma. Accurate measurement of GFR is essential for correct dosing. Isotopic methods remain the gold standard for the determination of GFR. Formulae to estimate GFR have improved the assessment of renal function in non-oncological settings. We assessed the utility of these formulae for carboplatin dosing.<p></p>
<b>Methods:</b> We studied consecutive subjects receiving adjuvant carboplatin for stage 1 seminoma at our institution between 2007 and 2012. Subjects underwent 51Cr-ethylene diamine tetra-acetic acid (EDTA) measurement of GFR with carboplatin dose calculated using the Calvert formula. Theoretical carboplatin doses were calculated from estimated GFR using Chronic Kidney Disease-Epidemiology (CKD-EPI), Management of Diet in Renal Disease (MDRD) and Cockcroft–Gault (CG) formulae with additional correction for actual body surface area (BSA). Carboplatin doses calculated by formulae were compared with dose calculated by isotopic GFR; a difference <10% was considered acceptable.<p></p>
<b>Results:</b> 115 patients were identified. Mean isotopic GFR was 96.9 ml/min/1.73 m2. CG and CKD-EPI tended to overestimate GFR whereas MDRD tended to underestimate GFR. The CKD-EPI formula had greatest accuracy. The CKD-EPI formula, corrected for actual BSA, performed best; 45.9% of patients received within 10% of correct carboplatin dose. Patients predicted as underdosed (13.5%) by CKD-EPI were more likely to be obese (p = 0.013); there were no predictors of the 40.5% receiving an excess dose.<p></p>
<b>Conclusions:</b> Our data support further evaluation of the CKD-EPI formula in this patient population but clinically significant variances in carboplatin dosing occur using non-isotopic methods of GFR estimation. Isotopic determination of GFR should remain the recommended standard for carboplatin dosing when accuracy is essential.<p></p>
The Relationship Between Aerobic and Anaerobic Performance in Recreational Runners
International Journal of Exercise Science 9(5): 625-634, 2016. Research has indicated that combined aerobic and anaerobic training (concurrent training) may improve aerobic performance greater than aerobic training alone. The purpose of this investigation was to establish any associations between aerobic and anaerobic performance. Eleven participants (n = 11, age = 34.1 ± 13 years, VO2max = 58.4 ± 7.8) volunteered for this study. Participants were asked for endurance training experience (4.7 ± 3.7 years) and resistance training experience (4.1 ± 4.6 years). To meet training status, participants were to have a VO2max in the 80th percentile as per ACSM guidelines. The Bruce treadmill test was used to measure aerobic performance. In order to measure anaerobic performance, several tests were completed utilizing a force platform. A Pearson Product R Correlation Coefficient was calculated to determine correlations between variables. The results show significant correlation between VO2max and RFD (r = 0.68). Further analyses utilizing Cohen’s effect size indicated a strong association between VO2max and peak force, as well as running efficiency and peak power, relative peak power, and power endurance. These results indicate an existing possibility that anaerobic performance measures such as RFD may have a positive relationship with aerobic performance measures such as VO2max. Therefore, it may be beneficial to integrate specific training components which focus on improving RFD as a method of improving running performance
What do we know about the risks for young people moving into, through and out of inpatient mental health care? Findings from an evidence synthesis.
Background Young people with complex or severe mental health needs sometimes require care and treatment in inpatient settings. There are risks for young people in this care context, and this study addressed the question: ‘What is known about the identification, assessment and management of risk in young people (aged 11–18) with complex mental health needs entering, using and exiting inpatient child and adolescent mental health services in the UK?’ Methods In phase 1 a scoping search of two electronic databases (MEDLINE and PsychINFO) was undertaken. Items included were themed and presented to members of a stakeholder advisory group, who were asked to help prioritise the focus for phase 2. In phase 2, 17 electronic databases (EconLit; ASSIA; BNI; Cochrane Library; CINAHL; ERIC; EMBASE; HMIC; MEDLINE; PsycINFO; Scopus; Social Care Online; Social Services Abstracts; Sociological Abstracts; OpenGrey; TRiP; and Web of Science) were searched. Websites were explored and a call for evidence was circulated to locate items related to the risks to young people in mental health hospitals relating to ‘dislocation’ and ‘contagion’. All types of evidence including research, policies and service and practice responses relating to outcomes, views and experiences, costs and cost-effectiveness were considered. Materials identified were narratively synthesised. Results In phase 1, 4539 citations were found and 124 items included. Most were concerned with clinical risks. In phase 2, 15,662 citations were found, and 40 addressing the risks of ‘dislocation’ and ‘contagion’ were included supplemented by 20 policy and guidance documents. The quality of studies varied. Materials were synthesised using the categories: Dislocation: Normal Life; Dislocation: Identity; Dislocation: Friends; Dislocation: Stigma; Dislocation: Education; Dislocation: Families; and Contagion. No studies included an economic analysis. Although we found evidence of consideration of risk to young people in these areas we found little evidence to improve practice and services. Conclusions The importance to stakeholders of the risks of ‘dislocation’ and ‘contagion’ contrasted with the limited quantity and quality of evidence to inform policy, services and practice. The risks of dislocation and contagion are important, but new research is needed to inform how staff might identify, assess and manage them
Selection of Post-Acute Care for Stroke Patients
Background: Significant variation exists in post-acute care for stroke survivors. This study examines referral practices of occupational and physical therapists for patients after acute stroke.
Method: Occupational therapists (OTs) and physical therapists (PTs) were surveyed either electronically or in person at a national conference. The respondents selected the most appropriate referral for each of five case vignettes. The referral choices included Inpatient Rehabilitation Facility (IRF), Skilled Nursing Facility (SNF), Long-Term Acute Care Hospital (LTACH), home with home services, or home with outpatient services. Demographic data included practice location, setting, and duration. The respondents were also asked to rate how strongly 15 clinical factors influence their referral decisions.
Results: The 33 OTs and 41 PTs favored similar referrals. Consensus was observed in four of the five cases. No differences were observed among the respondents based on practice location, practice setting, or number of years in practice and the referrals. Prognosis for functional improvement and pre-stroke functional status were identified as the most important factors influencing referral decisions.
Conclusion: Further studies are needed to define areas of broad consensus as well as areas of disagreement, with subsequent efforts to clarify optimal treatment algorithms for patients who currently receive variable rehabilitative care
Imaging biomarkers of adiposity and sarcopenia as potential predictors for overall survival among patients with endometrial cancer treated with bevacizumab
Objective:To examine associations of body mass index (BMI), subcutaneous fat area (SFA) and density (SFD), visceral fat area (VFA) and density (VFD) and total psoas area (TPA) to outcomes among patients receiving chemotherapy with or without bevacizumab for advanced or recurrent endometrial cancer (EC). Methods:This was a multi-institutional, retrospective study of patients with EC treated with and without bevacizumab as part of front-line, platinum based chemotherapy. Demographics and clinical characteristics were collected. SFA, VFA, SFD, VFD, and TPA were determined from pre-treatment CT scans using a deep learning algorithm. Data was compared with overall survival (OS) and progression free survival (PFS). Results:Seventy-eight patients were analyzed. The majority were Caucasian (87.2%) with a mean BMI of 34.7 kg/m2. PFS and OS did not differ between patients with BMI, SFA, VFA, SFD, VFD, or TPA ≥ the 50th percentile compared to <50th percentile (p = 0.91, 0.45, 0.71, 0.74, 0.60, and 0.74 respectively) and (p = 0.99, 0.59, 0.14, 0.77, and 0.85 respectively). When adjusting for prognostic factors, elevated VFA trended towards shorter OS (25.1 vs 59.5 months, HR = 1.68 [0.92-3.05]).Patients receiving bevacizumab had similar OS compared to those who did not (37.6 vs 44.5 months, p = 0.409). When stratified by adiposity markers, no subset demonstrated benefit from bevacizumab. Conclusion:Obesity has been associated with increased levels of vascular endothelial growth factor (VEGF), the main target for bevacizumab therapy. Imaging measurements of VFA may provide prognostic information for patients with EC but no adiposity marker was predictive of improved response to bevacizumab
Pattern formation during the evaporation of a colloidal nanoliter drop: a numerical and experimental study
An efficient way to precisely pattern particles on solid surfaces is to
dispense and evaporate colloidal drops, as for bioassays. The dried deposits
often exhibit complex structures exemplified by the coffee ring pattern, where
most particles have accumulated at the periphery of the deposit. In this work,
the formation of deposits during the drying of nanoliter colloidal drops on a
flat substrate is investigated numerically and experimentally. A finite-element
numerical model is developed that solves the Navier-Stokes, heat and mass
transport equations in a Lagrangian framework. The diffusion of vapor in the
atmosphere is solved numerically, providing an exact boundary condition for the
evaporative flux at the droplet-air interface. Laplace stresses and thermal
Marangoni stresses are accounted for. The particle concentration is tracked by
solving a continuum advection-diffusion equation. Wetting line motion and the
interaction of the free surface of the drop with the growing deposit are
modeled based on criteria on wetting angles. Numerical results for evaporation
times and flow field are in very good agreement with published experimental and
theoretical results. We also performed transient visualization experiments of
water and isopropanol drops loaded with polystyrene microsphere evaporating on
respectively glass and polydimethylsiloxane substrates. Measured evaporation
times, deposit shape and sizes, and flow fields are in very good agreement with
the numerical results. Different flow patterns caused by the competition of
Marangoni loops and radial flow are shown to determine the deposit shape to be
either a ring-like pattern or a homogeneous bump
Impact of Obesity on Modality Longevity, Residual Kidney Function, Peritonitis, and Survival Among Incident Peritoneal Dialysis Patients.
BACKGROUND:The prevalence of severe obesity, often considered a contraindication to peritoneal dialysis (PD), has increased over time. However, mortality has decreased more rapidly in the PD population than the hemodialysis (HD) population in the United States. The association between obesity and clinical outcomes among patients with end-stage kidney disease remains unclear in the current era. STUDY DESIGN:Historical cohort study. SETTING & PARTICIPANTS:15,573 incident PD patients from a large US dialysis organization (2007-2011). PREDICTOR:Body mass index (BMI). OUTCOMES:Modality longevity, residual renal creatinine clearance, peritonitis, and survival. RESULTS:Higher BMI was significantly associated with shorter time to transfer to HD therapy (P for trend < 0.001), longer time to kidney transplantation (P for trend < 0.001), and, with borderline significance, more frequent peritonitis-related hospitalization (P for trend = 0.05). Compared with lean patients, obese patients had faster declines in residual kidney function (P for trend < 0.001) and consistently achieved lower total Kt/V over time (P for trend < 0.001) despite greater increases in dialysis Kt/V (P for trend < 0.001). There was a U-shaped association between BMI and mortality, with the greatest survival associated with the BMI range of 30 to < 35kg/m2 in the case-mix adjusted model. Compared with matched HD patients, PD patients had lower mortality in the BMI categories of < 25 and 25 to < 35kg/m2 and had equivalent survival in the BMI category ≥ 35kg/m2 (P for interaction = 0.001 [vs < 25 kg/m2]). This attenuation in survival difference among patients with severe obesity was observed only in patients with diabetes, but not those without diabetes. LIMITATIONS:Inability to evaluate causal associations. Potential indication bias. CONCLUSIONS:Whereas obese PD patients had higher risk for complications than nonobese PD patients, their survival was no worse than matched HD patients
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