How does discharge against medical advice affect risk of mortality and unplanned readmission? A retrospective cohort study set in a large UK medical admissions unit.

OBJECTIVES: To assess the frequency of discharge against medical advice (DAMA) in a large UK teaching hospital, explore factors which increase the risk of DAMA and identify how DAMA impacts patient risk of mortality and readmission. DESIGN: Retrospective cohort study. SETTING: Large acute teaching hospital in the UK. PATIENTS: 36 683 patients discharged from the acute medical unit of a large UK teaching hospital between 1 January 2012 and 31 December 2016. MEASUREMENTS: Patients were censored on 1 January 2021. Mortality and 30-day unplanned readmission rates were assessed. Deprivation, age and sex were taken as covariates. RESULTS: 3% of patients discharged against medical advice. These patients were younger (median age (years) (IQR)): planned discharge (PD) 59 (40-77); DAMA 39 (28-51), predominantly of male sex (PD 48%; DAMA 66%) and were of greater social deprivation (in three most deprived quintiles PD 69%; DAMA 84%). DAMA was associated with increased risk of death in patients under the age of 33.3 years (adjusted HR 2.6 (1.2-5.8)) and increased incidence of 30-day readmission (standardised incidence ratio 1.9 (1.5-2.2)). LIMITATIONS: Readmission to acute hospitals outside of the local health board may have been missed. We were unable to include information regarding comorbidity or severity of presentation. CONCLUSIONS: These data highlight the vulnerability of younger patients who DAMA, even in a free-at-the-point-of-delivery healthcare setting.

Control of human cytomegalovirus replication by liver resident natural killer cells.

Natural killer cells are considered to be important for control of human cytomegalovirus- a major pathogen in immune suppressed transplant patients. Viral infection promotes the development of an adaptive phenotype in circulating natural killer cells that changes their anti-viral function. In contrast, less is understood how natural killer cells that reside in tissue respond to viral infection. Here we show natural killer cells resident in the liver have an altered phenotype in cytomegalovirus infected individuals and display increased anti-viral activity against multiple viruses in vitro and identify and characterise a subset of natural killer cells responsible for control. Crucially, livers containing natural killer cells with better capacity to control cytomegalovirus replication in vitro are less likely to experience viraemia post-transplant. Taken together, these data suggest that virally induced expansion of tissue resident natural killer cells in the donor organ can reduce the chance of viraemia post-transplant.

Prospective, multicentre study of screening, investigation and management of hyponatraemia after subarachnoid haemorrhage in the UK and Ireland.

BACKGROUND: Hyponatraemia often occurs after subarachnoid haemorrhage (SAH). However, its clinical significance and optimal management are uncertain. We audited the screening, investigation and management of hyponatraemia after SAH. METHODS: We prospectively identified consecutive patients with spontaneous SAH admitted to neurosurgical units in the United Kingdom or Ireland. We reviewed medical records daily from admission to discharge, 21 days or death and extracted all measurements of serum sodium to identify hyponatraemia (<135 mmol/L). Main outcomes were death/dependency at discharge or 21 days and admission duration >10 days. Associations of hyponatraemia with outcome were assessed using logistic regression with adjustment for predictors of outcome after SAH and admission duration. We assessed hyponatraemia-free survival using multivariable Cox regression. RESULTS: 175/407 (43%) patients admitted to 24 neurosurgical units developed hyponatraemia. 5976 serum sodium measurements were made. Serum osmolality, urine osmolality and urine sodium were measured in 30/166 (18%) hyponatraemic patients with complete data. The most frequently target daily fluid intake was >3 L and this did not differ during hyponatraemic or non-hyponatraemic episodes. 26% (n/N=42/164) patients with hyponatraemia received sodium supplementation. 133 (35%) patients were dead or dependent within the study period and 240 (68%) patients had hospital admission for over 10 days. In the multivariable analyses, hyponatraemia was associated with less dependency (adjusted OR (aOR)=0.35 (95% CI 0.17 to 0.69)) but longer admissions (aOR=3.2 (1.8 to 5.7)). World Federation of Neurosurgical Societies grade I-III, modified Fisher 2-4 and posterior circulation aneurysms were associated with greater hazards of hyponatraemia. CONCLUSIONS: In this comprehensive multicentre prospective-adjusted analysis of patients with SAH, hyponatraemia was investigated inconsistently and, for most patients, was not associated with changes in management or clinical outcome. This work establishes a basis for the development of evidence-based SAH-specific guidance for targeted screening, investigation and management of high-risk patients to minimise the impact of hyponatraemia on admission duration and to improve consistency of patient care.

Corticotroph isolation from Pomc-eGFP mice reveals sustained transcriptional dysregulation characterising a mouse model of glucocorticoid-induced suppression of the hypothalamus-pituitary-adrenal axis.

Glucocorticoids (GC) are prescribed for periods > 3 months to 1%-3% of the UK population; 10%-50% of these patients develop hypothalamus-pituitary-adrenal (HPA) axis suppression, which may last over 6 months and is associated with morbidity and mortality. Recovery of the pituitary and hypothalamus is necessary for recovery of adrenal function. We developed a mouse model of dexamethasone (DEX)-induced HPA axis dysfunction aiming to further explore recovery in the pituitary. Adult male wild-type C57BL6/J or Pomc-eGFP transgenic mice were randomly assigned to receive DEX (approximately 0.4 mg kg-1 bodyweight day-1 ) or vehicle via drinking water for 4 weeks following which treatment was withdrawn and tissues were harvested after another 0, 1, and 4 weeks. Corticotrophs were isolated from Pomc-eGFP pituitaries using fluorescence-activated cell sorting, and RNA extracted for RNA-sequencing. DEX treatment suppressed corticosterone production, which remained partially suppressed at least 1 week following DEX withdrawal. In the adrenal, Hsd3b2, Cyp11a1, and Mc2r mRNA levels were significantly reduced at time 0, with Mc2r and Cyp11a1 remaining reduced 1 week following DEX withdrawal. The corticotroph transcriptome was modified by DEX treatment, with some differences between groups persisting 4 weeks following withdrawal. No genes supressed by DEX exhibited ongoing attenuation 1 and 4 weeks following withdrawal, whereas only two genes were upregulated and remained so following withdrawal. A pattern of rebound at 1 and 4 weeks was observed in 14 genes that increased following suppression, and in six genes that were reduced by DEX and then increased. Chronic GC treatment may induce persistent changes in the pituitary that may influence future response to GC treatment or stress.

Investigation and management of serum sodium after subarachnoid haemorrhage (SaSH): a survey of practice in the United Kingdom and Republic of Ireland.

BACKGROUND: Hyponatraemia is a common complication of aneurysmal subarachnoid haemorrhage (SAH). We aimed to determine current neurosurgical practice for the identification, investigation and management of hyponatraemia after SAH. METHODS: An online questionnaire was completed by UK and Irish neurosurgical trainees and consultant collaborators in the Sodium after Subarachnoid Haemorrhage (SaSH) audit. RESULTS: Between August 2019 and June 2020, 43 responses were received from 31 of 32 UK and Ireland adult neurosurgical units (NSUs). All units reported routine measurement of serum sodium either daily or every other day. Most NSUs reported routine investigation of hyponatraemia after SAH with paired serum and urinary osmolalities (94%), urinary sodium (84%), daily fluid balance (84%), but few measured glucose (19%), morning cortisol (13%), or performed a short Synacthen test (3%). Management of hyponatraemia was variable, with units reporting use of oral sodium supplementation (77%), fluid restriction (58%), hypertonic saline (55%), and fludrocortisone (19%). CONCLUSIONS: Reported assessment of serum sodium after SAH was consistent between units, whereas management of hyponatraemia varied. This may reflect the lack of a specific evidence-base to inform practice.

Lifestyle modifications for nonalcohol-related fatty liver disease: a network meta-analysis.

BACKGROUND: The prevalence of nonalcohol-related fatty liver disease (NAFLD) varies between 19% and 33% in different populations. NAFLD decreases life expectancy and increases the risks of liver cirrhosis, hepatocellular carcinoma, and requirement for liver transplantation. There is uncertainty surrounding the relative benefits and harms of various lifestyle interventions for people with NAFLD. OBJECTIVES: To assess the comparative benefits and harms of different lifestyle interventions in the treatment of NAFLD through a network meta-analysis, and to generate rankings of the different lifestyle interventions according to their safety and efficacy. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, Science Citation Index Expanded, Conference Proceedings Citation Index - Science, World Health Organization International Clinical Trials Registry Platform, and trials registers until February 2021 to identify randomised clinical trials in people with NAFLD. SELECTION CRITERIA: We included only randomised clinical trials (irrespective of language, blinding, or status) in people with NAFLD, whatever the method of diagnosis, age, and diabetic status of participants, or presence of non-alcoholic steatohepatitis (NASH). We excluded randomised clinical trials in which participants had previously undergone liver transplantation. DATA COLLECTION AND ANALYSIS: We planned to perform a network meta-analysis with OpenBUGS using Bayesian methods and to calculate the differences in treatments using hazard ratios (HRs), odds ratios (ORs), and rate ratios (RaRs) with 95% credible intervals (CrIs) based on an available-participant analysis, according to National Institute of Health and Care Excellence Decision Support Unit guidance. However, the data were too sparse for the clinical outcomes. We therefore performed only direct comparisons (head-to-head comparisons) with OpenBUGS using Bayesian methods. MAIN RESULTS: We included a total of 59 randomised clinical trials (3631 participants) in the review. All but two trials were at high risk of bias. A total of 33 different interventions, ranging from advice to supervised exercise and special diets, or a combination of these and no additional intervention were compared in these trials. The reference treatment was no active intervention. Twenty-eight trials (1942 participants) were included in one or more comparisons. The follow-up ranged from 1 month to 24 months. The remaining trials did not report any of the outcomes of interest for this review. The follow-up period in the trials that reported clinical outcomes was 2 months to 24 months. During this short follow-up period, clinical events related to NAFLD such as mortality, liver cirrhosis, liver decompensation, liver transplantation, hepatocellular carcinoma, and liver-related mortality were sparse. This is probably because of the very short follow-up periods. It takes a follow-up of 8 years to 28 years to detect differences in mortality between people with NAFLD and the general population. It is therefore unlikely that differences by clinical outcomes will be noted in trials with less than 5 years to 10 years of follow-up. In one trial, one participant developed an adverse event. There were no adverse events in any of the remaining participants in this trial, or in any of the remaining trials, which seemed to be directly related to the intervention. AUTHORS' CONCLUSIONS: The evidence indicates considerable uncertainty about the effects of the lifestyle interventions compared with no additional intervention (to general public health advice) on any of the clinical outcomes after a short follow-up period of 2 months to 24 months in people with nonalcohol-related fatty liver disease. Accordingly, high-quality randomised clinical trials with adequate follow-up are needed. We propose registry-based randomised clinical trials or cohort multiple randomised clinical trials (a study design in which multiple interventions are trialed within large longitudinal cohorts of participants to gain efficiencies and align trials more closely to standard clinical practice), comparing aerobic exercise and dietary advice versus standard of care (exercise and dietary advice received as part of national health promotion). The reason for the choice of aerobic exercise and dietary advice is the impact of these interventions on indirect outcomes which may translate to clinical benefit. The outcomes in such trials should be mortality, health-related quality of life, decompensated liver cirrhosis, liver transplantation, and resource use measures including costs of intervention and decreased healthcare use after a minimum follow-up of eight years, to find meaningful differences in the clinically important outcomes.

Novel behavioral interventions to improve long-term weight loss: A randomized trial of acceptance and commitment therapy or self-regulation for weight loss maintenance.

Maintenance of weight loss is hard to achieve, and novel interventions are needed to improve long-term outcomes. In this pilot randomized controlled trial, N = 188 participants received an online, 12-week weight loss intervention and N = 102 who lost ≥ 5% were then randomly assigned to a 1-day, 5-h workshop based on Acceptance and Commitment Therapy (ACT), Self-Regulation (SR), or no workshop (Control) with 3 months of limited email follow-up. Assessments were conducted at baseline, 3, 6, 12, 18, and 24 months. The primary outcome was percent weight change; secondary outcomes were weight-related experiential avoidance and health values-consistent behavior. ACT had greater overall weight loss (-7.18%, SE = 1.33) when compared to Control (-1.15%, SE = 1.50; p = .03). Post hoc analyses showed that ACT had significantly greater weight losses than Control (6.11%, ß = -2.03, p = .048) among those with lower initial weight loss (5-7%), and significantly greater weight loss than SR (6.19%, ß = -1.77, p = .05) among those with the highest initial weight losses (10% +). There is potential for continuing to develop ACT in a limited interventionist-contact format with modifications. This pilot study represents an innovative model for behavioral weight loss by reversing the typical treatment intensity model with the aim of providing interventionist support during a critical period after initial weight loss. REGISTRATION: Clinicaltrials.org #NCT02156752 https://www.clinicaltrials.gov/ct2/show/NCT02156752 .

Comparing Acceleration and Change of Direction Ability Between Backpedal and Cross-over Run Techniques for Use in American Football.

ABSTRACT: Angelino, D, McCabe, TJG, and Earp, JE. Comparing acceleration and change of direction ability between backpedal and cross-over run techniques for use in American football. J Strength Cond Res 35(1): 47-55, 2021-In American football, defensive backs guard receivers using either cross-over (CO) run or backpedal (BP) techniques, but the efficacy of these techniques is unknown. The purpose of this study was to compare linear acceleration (LA) and change of direction (CoD) ability when using CO and BP. Collegiate football defensive backs participated in LA (n = 13) and CoD (n = 7) testing. During LA, subjects performed CO, BP, and forward sprints with split times taken between 0-3 and 3-5 yd and ground reaction forces recorded 0 and 3 yd from the start. During CoD testing, subjects performed the CO or BP for 3 yd and then were given a cue to sprint to a gate 5 yd away in 1 of 4 directions (downfield, midfield, sideline, or upfield). In LA, CO was faster than BP between 0-3 yd (Δ -0.20 ± 0.02 seconds, p = 0.000) and 3-5 yd (Δ -0.12 ± 0.02 seconds, p = 0.000). At the start of the movement, CO demonstrated greater propulsive forces (p = 0.017). However, 3 yd from the start, CO demonstrated greater propulsive forces and reduced braking forces (p = 0.000 & 0.003). In CoD, CO was faster than BP when running in the downfield (Δ 0.21 ± 0.05 seconds, p = 0.044) and lateral directions (Δ 0.21 ± 0.08 seconds, p = 0.035), but similar in the upfield direction (Δ 0.01 ± 0.08, p = 0.986). Our results indicate that CO is superior to BP in LA, CoD ability, and movement efficiency and support the use of CO for defensive backs.

Multiplex Label Free Characterization of Cancer Cell Lines Using Surface Plasmon Resonance Imaging.

Rapid multiplex cell surface marker analysis can expedite investigations in which large number of antigens need to be analyzed. Simultaneous analysis of multiple surface antigens at the same level of sensitivity is however limited in the current golden standard analysis method, flow cytometry. In this paper we introduce a surface plasmon resonance imaging (SPRi)-based technique for 44-plex parameter analysis using a single sample, in less than 20 min. We analyzed the expression on cells from five different cancer cell lines by SPRi on a 44-plex antibody array including 4 negative controls and compared the output with flow cytometry. The combined correlation of the markers that showed expression by flow cytometry was 0.76. The results demonstrate as a proof of principle that SPRi can be applied for rapid semi-quantitative multiplex cell surface marker analysis.

Poly(bis-arylimidazoliums) possessing high hydroxide ion exchange capacity and high alkaline stability.

Solid polymer electrolyte electrochemical energy conversion devices that operate under highly alkaline conditions afford faster reaction kinetics and the deployment of inexpensive electrocatalysts compared with their acidic counterparts. The hydroxide anion exchange polymer is a key component of any solid polymer electrolyte device that operates under alkaline conditions. However, durable hydroxide-conducting polymer electrolytes in highly caustic media have proved elusive, because polymers bearing cations are inherently unstable under highly caustic conditions. Here we report a systematic investigation of novel arylimidazolium and bis-arylimidazolium compounds that lead to the rationale design of robust, sterically protected poly(arylimidazolium) hydroxide anion exchange polymers that possess a combination of high ion-exchange capacity and exceptional stability.

Weight self-stigma and weight loss during behavioural weight loss intervention.

OBJECTIVE: Despite the myriad negative effects of weight self-stigma, its role in weight loss intervention has not been thoroughly examined. The aim of this study was to examine the association between weight self-stigma and weight loss. METHODS: This longitudinal study examined the association between weight loss and changes in self-stigma, assessed by the Weight Self-Stigma Questionnaire, which distinguished between self-devaluation and fear of enacted stigma. Participants were adults with overweight or obesity enrolled in a 24-month weight loss intervention trial (groups were collapsed for this post hoc analysis) who were assessed at baseline, 6, 12, 18 and 24 months. RESULTS: Baseline levels of self-stigma were not associated with weight loss outcomes. However, mixed models analysis showed that reductions in one aspect of weight self-stigma, self-devaluation, was associated with greater weight loss (p = 0.01). Cross products mediation analysis showed that increases in use of weight control strategies mediated the association between reductions in self-devaluation and greater weight loss (F = 14.86, p < 0.001; CI 0.09-0.37). CONCLUSIONS: Results suggest that there may be potential for incorporating intervention methods targeting the reduction of self-stigma in order to improve weight loss outcomes.

Sulfophenylated Terphenylene Copolymer Membranes and Ionomers.

The copolymerization of a prefunctionalized, tetrasulfonated oligophenylene monomer was investigated. The corresponding physical and electrochemical properties of the polymers were tuned by varying the ratio of hydrophobic to hydrophilic units within the polymers. Membranes prepared from these polymers possessed ion exchange capacities ranging from 1.86 to 3.50 meq g-1 and exhibited proton conductivities of up to 338 mS cm-1 (80 °C, 95 % relative humidity). Small-angle X-ray scattering and small-angle neutron scattering were used to elucidate the effect of the monomer ratios on the polymer morphology. The utility of these materials as low gas crossover, highly conductive membranes was demonstrated in fuel cell devices. Gas crossover currents through the membranes of as low as 4 % (0.16±0.03 mA cm-2 ) for a perfluorosulfonic acid reference membrane were demonstrated. As ionomers in the catalyst layer, the copolymers yielded highly active porous electrodes and overcame kinetic losses typically observed for hydrocarbon-based catalyst layers. Fully hydrocarbon, nonfluorous, solid polymer electrolyte fuel cells are demonstrated with peak power densities of 770 mW cm-2 with oxygen and 456 mW cm-2 with air.

Mobile learning in medicine: an evaluation of attitudes and behaviours of medical students.

BACKGROUND: Mobile learning (mLearning) devices (such as tablets and smartphones) are increasingly part of the clinical environment but there is a limited and somewhat conflicting literature regarding the impact of such devices in the clinical learning environment. This study aims to: assess the impact of mLearning devices in the clinical learning environment on medical students' studying habits, attitudes towards mobile device supported learning; and the perceived reaction of clinicians and patients to the use of these devices as part of learning in the clinical setting. METHODS: Over three consecutive academic years, 18 cohorts of medical students (total n = 275) on a six-week rotation at a large teaching hospital in London were supplied with mLearning devices (iPad mini) to support their placement-based learning. Feedback on their experiences and perceptions was collected via pre- and post-use questionnaires. RESULTS: The results suggest mLearning devices have a positive effect on the students' perceived efficiency of working, while experience of usage not only confirmed pre-existing positive opinions about devices but also disputed some expected limitations associated with mLearning devices in the clinical workplace. Students were more likely to use devices in 'down-time' than as part of their clinical learning. As anticipated, both by users and from the literature, universal internet access was a major limitation to device use. The results were inconclusive about the student preference for device provision versus supporting a pre-owned device. CONCLUSION: M-learning devices can have a positive impact on the learning experiences medical students during their clinical attachments. The results supported the feasibility of providing mLearning devices to support learning in the clinical environment. However, universal internet is a fundamental limitation to optimal device utilisation.

Weight loss and frequency of body-weight self-monitoring in an online commercial weight management program with and without a cellular-connected 'smart' scale: a randomized pilot study.

Objective: Evaluate the effects of an online commercial weight management program, with and without provision of a 'smart' scale with instructions to weigh daily and weekly tailored feedback, on weight loss and the frequency of body-weight self-monitoring. Methods: Participants (N = 92; body mass index 27-40 kg/m2) were randomized to 6 months of no-cost access to the Weight Watchers Online (WWO) platform alone, or enhanced with a cellular-connected 'smart' scale, instructions to weigh daily and weekly pre-scripted email feedback (Weight Watchers Online Enhanced [WWO-E]). The number of days that weight was self-monitored (via 'smart' scale in WWO-E and manually in WWO) was recorded automatically across the 6-month trial. Objective weight was measured at baseline, 3 and 6 months. Results: While both groups achieved statistically significant weight loss, mean ± standard error weight loss did not differ between WWO-E and WWO at 3 months (5.1 ± 0.6 kg vs. 4.0 ± 0.7 kg, respectively; p = 0.257) or 6 months (5.3 ± 0.6 kg vs. 3.9 ± 0.7 kg, respectively; p = 0.116). However, a greater proportion of WWO-E lost ≥5% of initial body weight at 3 months (52.2% vs. 28.3%; p = 0.033), but not 6 months (43.5% vs. 30.4%; p = 0.280), compared with WWO. Mean ± standard deviation days with self-monitored weight was higher in WWO-E (80.5 ± 5.6; 44.7% of days) than WWO (12.0 ± 1.0; 6.7% of days; p < 0.001) across the 6-month study period. Conclusions: This is the first study to show that provision of a 'smart' scale with weekly tailored feedback substantially increased the frequency of self-weighing and the proportion of participants achieving an initial clinically significant ≥5% weight loss (52% vs. 28%) in an online commercial weight management program. Both WWO and WWO-E produced significant weight loss over 6 months. While mean weight losses were slightly greater in the enhanced group, the difference was not statistically significant in this small sample. This study provides support for the clinical utility of online commercial weight management programs and the potential for supporting technology such as 'smart' scales to improve adherence to body-weight self-monitoring and clinical outcomes.

Exploring process variables through which acceptance-based behavioral interventions may improve weight loss maintenance.

OBJECTIVE: A previously published randomized trial with individuals reporting high internal disinhibition showed significant differences in post-treatment weight change favoring Acceptance-Based Behavioral Intervention (ABBI) when compared to standard behavioral treatment (SBT). This paper examines process variables that might contribute to the observed differences in weight change. METHODS: Participants were 162 adults with overweight or obesity (mean BMI 37.6) randomly assigned to ABBI or SBT. Both interventions provided the same calorie intake target, exercise goal, and self-monitoring skills training. SBT incorporated current best practice interventions for addressing problematic thoughts and emotions. ABBI utilized acceptance-based techniques based on Acceptance and Commitment Therapy. ABBI and SBT were compared on process measures hypothesized to be related to outcome in ABBI and SBT and their association with weight loss outcomes using linear and non-linear mixed models methods and exploratory correlational analyses. RESULTS: Both the SBT and the ABBI groups showed significant changes over time on all process variables. The only significant between group difference was for values consistent behavior, with the ABBI group improving more as compared to SBT (t=2.45, p=.016); however, changes in values consistent behavior did not mediate weight change. Exploratory analyses suggest the possibility that changes in process variables were less associated with weight change in ABBI than in SBT after treatment was discontinued. CONCLUSIONS: Both conditions produced significant changes in process variables, however there was little difference between groups. Thus, the results do not provide an adequate process account for the observed weight change differences between ABBI and SBT, leaving important questions that need to be addressed by future research.

Successful weight loss maintainers use health-tracking smartphone applications more than a nationally representative sample: comparison of the National Weight Control Registry to Pew Tracking for Health.

OBJECTIVE: The objective of this paper is to evaluate successful weight loss maintainers' use of self-monitoring technology. METHODS: National Weight Control Registry (NWCR) participants, who maintained a ≥13.6 kg weight loss for ≥1 year, completed an online survey about self-monitoring technology use. The NWCR sample (n = 794) was compared with a demographically similar subsample of 833 individuals answering the same questions in the Pew Tracking for Health Survey. RESULTS: The NWCR had higher rates of tracking weight, diet or exercise using any modality (92.8% vs. 71.3%), on a regular basis (67.4% vs. 41.3%), and frequency of updating records, compared with Pew (ps < .01). Smartphone ownership was higher in NWCR participants (80.2% vs. 52.8%, p < .001), and NWCR smartphone owners had 23.1 times greater odds for using diet, food or calorie counter apps (58.9% vs. 5.9%) and 15.5 times greater odds for using weight monitoring apps (31.7% vs. 3.0%; all ps < .01). Pew respondents more often changed their behaviour based on their tracking data (ps < .01). CONCLUSION: Use of self-monitoring technology is common in weight loss maintainers: more so than in a nationally representative sample. However, the national sample more often changed their behaviour based on tracking data, perhaps suggesting that weight loss maintainers could derive additional benefit from technology they are already using.

Highly Stable, Low Gas Crossover, Proton-Conducting Phenylated Polyphenylenes.

Two classes of novel sulfonated phenylated polyphenylene ionomers are investigated as polyaromatic-based proton exchange membranes. Both types of ionomer possess high ion exchange capacities yet are insoluble in water at elevated temperatures. They exhibit high proton conductivity under both fully hydrated conditions and reduced relative humidity, and are markedly resilient to free radical attack. Fuel cells constructed with membrane-electrode assemblies containing each ionomer membrane yield high in situ proton conductivity and peak power densities that are greater than obtained using Nafion reference membranes. In situ chemical stability accelerated stress tests reveal that this class of the polyaromatic membranes allow significantly lower gas crossover and lower rates of degradation than Nafion benchmark systems. These results point to a promising future for molecularly designed sulfonated phenylated polyphenylenes as proton-conducting media in electrochemical technologies.

Conservative management of migrated percutaneous endoscopic colostomy tube.

A 68-year-old male nursing home resident presented following dislodgement of a percutaneous endoscopic colostomy (PEC) tube originally sited to prevent recurrent sigmoid volvulus. Computed tomography demonstrated tube migration into the lumen of the recto-sigmoid junction, where it remained for 12 days before passing spontaneously. During this period, the patient remained asymptomatic; the residual colocutaneous fistula functioned as a decompressive valve. Originally, the patient was due to be discharged with early flexible sigmoidoscopy follow-up. However, complex social issues delayed discharge. During his admission, a second PEC tube was successfully inserted next to the previous colostomy site without complication. This is an unusual case and no similar episodes of asymptomatic PEC migration have been reported. We demonstrate that such cases may be offered an appropriate trial of conservative management. Here, we describe our experience and critically appraise the literature.

Cationic Polyelectrolytes, Stable in 10 M KOHaq at 100 °C.

We report on poly(arylene-imidazoliums), which were synthesized by microwave polycondensation of dialdehyde with bisbenzil and quantitatively functionalized by alkylation. This cationic polyelectrolyte is sterically protected around the C2-position and is stable in 10 M KOHaq at 100 °C (t1/2 of >5000 h). Alkaline stability is rationalized through analyses of model compounds, single crystal X-ray diffraction, and density functional theory. The polyelectrolytes form tough, pliable, transparent, ionically conductive films.

Intervention-related increases in preoperative physical activity are maintained 6-months after Bariatric surgery: results from the bari-active trial.

Higher preoperative physical activity (PA) strongly predicts higher post-operative PA in bariatric surgery (BS) patients, providing rationale for preoperative PA interventions (PAIs). However, whether PAI-related increases can be maintained post-operatively has not been examined. This study compared PA changes across pre- (baseline, post-intervention) and post-operative (6-month follow up) periods in participants randomized to 6 weeks of preoperative PAI or standard care control (SC). Of 75 participants initially randomized, 36 (PAI n=22; SC n=14) underwent BS. Changes in daily bout-related (⩾10-min bouts) moderate-to-vigorous PA (MVPA) and steps were assessed via the SenseWear Armband monitor. PAI received weekly counseling to increase walking exercise. Retention (86%) at post-operative follow up was similar between groups. Intent-to-treat analyses showed that PAI vs SC had greater increases across time (baseline, post-intervention, follow up) in bout-related MVPA minutes/day (4.3±5.1, 26.3±21.3, 28.7±26.3 vs 10.4±22.9, 11.4±16.0, 18.5±28.2; P=0.013) and steps/day (5163±2901, 7950±3286, 7870±3936 vs 5163±2901, 5601±3368, 5087±2603; P<0.001). PAI differed from SC on bout-related MVPA at post-intervention (P=0.016; d=0.91), but not follow up (P=0.15; d=0.41), and steps at post-intervention (P=0.031; d=0.78) and follow up (P=0.024; d=0.84). PAI participants maintained preoperative PA increases post-operatively. Findings support preoperative PAIs and research to test whether PA changes can be sustained and influence surgical outcomes beyond the initial post-operative period.