Modeling of Bubble Growth Dynamics and Nonisothermal Expansion in Starch-Based Foams During Extrusion

A mathematical model was developed to describe expansion phenomena in starch-based foams during extrusion. The model was divided into three parts to describe the microbubble growth dynamics, to couple bubble growth with extrudate expansion, and to describe the macrotransport phenomena in the extrudate, respectively. The differential equations involved in the model were solved by finite element schemes. For validating the model, the predicted radius, density, and residual moisture of final extrudate were compared with experimental data. Standard deviations between the predicted and experimental radius, density, and residual moisture of final extrudates were 16.7%, 11.2%, and 39.3%, respectively. The model was used to predict the profiles of downstream velocity, expansion ratio, moisture content, and temperature of extrudate during expansion

Short course daily prednisolone therapy during an upper respiratory tract infection in children with relapsing steroid-sensitive nephrotic syndrome (PREDNOS 2):protocol for a randomised controlled trial

BACKGROUND: Relapses of childhood steroid-sensitive nephrotic syndrome (SSNS) are treated with a 4- to 8-week course of high-dose oral prednisolone, which may be associated with significant adverse effects. There is a clear association between upper respiratory tract infection (URTI) and relapse development. Previous studies in developing nations have suggested that introducing a 5- to 7-day course of daily prednisolone during an URTI may prevent a relapse developing and the need for a treatment course of high-dose prednisolone. The aim of PREDNOS 2 is to evaluate the effectiveness of a 6-day course of daily prednisolone therapy during an URTI in reducing the development of a subsequent relapse in a developed nation.METHODS/DESIGN: The subjects will be 300 children with relapsing SSNS (≥2 relapses in preceding year), who will be randomised to receive either a 6-day course of daily prednisolone or no change to their current therapy (with the use of placebo to double blind) each time they develop an URTI over 12 months. A strict definition for URTI will be used. Subjects will be reviewed at 3, 6, 9 and 12 months to capture data regarding relapse history, ongoing therapy and adverse effect profile, including behavioural problems and quality of life. A formal health economic analysis will also be performed. The primary end point of the study will be the incidence of URTI-related relapse (3 days of Albustix +++) following the first infection during the 12-month follow-up period. DNA and RNA samples will be collected to identify a potential genetic cause for the disease. Subjects will be recruited from over 100 UK centres with the assistance of the Medicines for Children Research Network. PREDNOS 2 is funded by the National Institute for Health Research Health Technology Assessment Programme (11/129/261).DISCUSSION: We propose that PREDNOS 2 will be a pivotal study that will inform the future standard of care for children with SSNS. If it is possible to reduce the disease relapse rate effectively and safely, this will reduce the morbidity and cost associated with drug treatment, notwithstanding hospital admission and parental absence from employment.TRIAL REGISTRATION: Current Controlled Trials (ISRCTN10900733).</p

A multinuclear solid state NMR, density functional theory and X-Ray diffraction study of hydrogen bonding in Group I hydrogen dibenzoates

An NMR crystallographic approach incorporating multinuclear solid state NMR (SSNMR), X-ray structure determinations and density functional theory (DFT) are used to characterise the H bonding arrangements in benzoic acid (BZA) and the corresponding Group I alkali metal hydrogen dibenzoates (HD) systems. Since the XRD data often cannot precisely confirm the proton position within the hydrogen bond, the relationship between the experimental SSNMR parameters and the ability of gauge included plane augmented wave (GIPAW) DFT to predict them becomes a powerful constraint that can assist with further structure refinement. Both the 1H and 13C MAS NMR methods provide primary descriptions of the H bonding via accurate measurements of the 1H and 13C isotropic chemical shifts, and the individual 13C chemical shift tensor elements; these are unequivocally corroborated by DFT calculations, which together accurately describe the trend of the H bonding strength as the size of the monovalent cation changes. In addition, 17O MAS and DOR NMR form a powerful combination to characterise the O environments, with the DOR technique providing highly resolved 17O NMR data which helps verify unequivocally the number of inequivalent O positions for the conventional 17O MAS NMR to process. Further multinuclear MAS and static NMR studies involving the quadrupolar 7Li, 39K, 87Rb and 133Cs nuclei, and the associated DFT calculations, provide trends and a corroboration of the H bond geometry which assist in the understanding of these arrangements. Even though the crystallographic H positions in each H bonding arrangement reported from the single crystal X-ray studies are prone to uncertainty, the good corroboration between the measured and DFT calculated chemical shift and quadrupole tensor parameters for the Group I alkali species suggest that these reported H positions are reliable

Daily low-dose prednisolone to prevent relapse of steroid-sensitive nephrotic syndrome in children with an upper respiratory tract infection:PREDNOS2 RCT

BACKGROUND: Most children with steroid-sensitive nephrotic syndrome have relapses that are triggered by upper respiratory tract infections. Four small trials, mostly in children already taking maintenance corticosteroid in countries of different upper respiratory tract infection epidemiology, showed that giving daily low-dose prednisone/prednisolone for 5-7 days during an upper respiratory tract infection reduces the risk of relapse. OBJECTIVES: To determine if these findings were replicated in a large UK population of children with relapsing steroid-sensitive nephrotic syndrome on different background medication or none. DESIGN: A randomised double-blind placebo-controlled trial, including a cost-effectiveness analysis. SETTING: A total of 122 UK paediatric departments, of which 91 recruited patients. PARTICIPANTS: A total of 365 children with relapsing steroid-sensitive nephrotic syndrome (mean age 7.6 ± 3.5 years) were randomised (1 : 1) according to a minimisation algorithm based on background treatment. Eighty children completed 12 months of follow-up without an upper respiratory tract infection. Thirty-two children were withdrawn from the trial (14 prior to an upper respiratory tract infection), leaving a modified intention-to-treat analysis population of 271 children (134 and 137 children in the prednisolone and placebo arms, respectively). INTERVENTIONS: At the start of an upper respiratory tract infection, children received 6 days of prednisolone (15 mg/m2) or an equivalent dose of placebo. MAIN OUTCOME MEASURES: The primary outcome was the incidence of first upper respiratory tract infection-related relapse following any upper respiratory tract infection over 12 months. The secondary outcomes were the overall rate of relapse, changes in background treatment, cumulative dose of prednisolone, rates of serious adverse events, incidence of corticosteroid adverse effects, change in Achenbach Child Behaviour Checklist score and quality of life. Analysis was by intention-to-treat principle. The cost-effectiveness analysis used trial data and a decision-analytic model to estimate quality-adjusted life-years and costs at 1 year, which were then extrapolated over 16 years. RESULTS: There were 384 upper respiratory tract infections and 82 upper respiratory tract infection-related relapses in the prednisolone arm, and 407 upper respiratory tract infections and 82 upper respiratory tract infection-related relapses in the placebo arm. The number of patients experiencing an upper respiratory tract infection-related relapse was 56 (42.7%) and 58 (44.3%) in the prednisolone and placebo arms, respectively (adjusted risk difference -0.024, 95% confidence interval -0.14 to 0.09; p = 0.70). There was no evidence that the treatment effect differed when data were analysed according to background treatment. There were no significant differences in secondary outcomes between treatment arms. Giving daily prednisolone at the time of an upper respiratory tract infection was associated with increased quality-adjusted life-years (0.9427 vs. 0.9424) and decreased average costs (£252 vs. £254), when compared with standard care. The cost saving was driven by background therapy and hospitalisations after relapse. The finding was robust to sensitivity analysis. LIMITATIONS: A larger number of children than expected did not have an upper respiratory tract infection and the sample size attrition rate was adjusted accordingly during the trial. CONCLUSIONS: The clinical analysis indicated that giving 6 days of daily low-dose prednisolone at the time of an upper respiratory tract infection does not reduce the risk of relapse of steroid-sensitive nephrotic syndrome in UK children. However, there was an economic benefit from costs associated with background therapy and relapse, and the health-related quality-of-life impact of having a relapse. FUTURE WORK: Further work is needed to investigate the clinical and health economic impact of relapses, interethnic differences in treatment response, the effect of different corticosteroid regimens in treating relapses, and the pathogenesis of individual viral infections and their effect on steroid-sensitive nephrotic syndrome. TRIAL REGISTRATION: Current Controlled Trials ISRCTN10900733 and EudraCT 2012-003476-39. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 3. See the NIHR Journals Library website for further project information

Sixty Years of Modern Human Origins in the American Anthropological Association

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65197/1/aa.2003.105.1.89.pd

Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey

Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10&nbsp;years; 78.2% included were male with a median age of 37&nbsp;years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020