In-flight measurement of ice growth on an airfoil using an array of ultrasonic transducers

Results of preliminary tests to measure ice growth on an airfoil during flight icing conditions are presented. Ultrasonic pulse echo measurements of ice thickness are obtained from an array of eight ultrasonic transducers mounted flush with the leading edge of the airfoil. These thickness measurements are used to document the evolution of the ice shape during the encounter in the form of successive ice profiles. Results from 3 research flights are presented and discussed. The accuracy of the ultrasonic measurements is found to be within 0.5 mm of mechanical and stereo photograph measurements of the ice accretion

Development of a wearable bioartificial kidney using the Bioartificial Renal Epithelial Cell System (BRECS)

Cell therapy for the treatment of renal failure in the acute setting has proved successful, with therapeutic impact, yet development of a sustainable, portable bioartificial kidney for treatment of chronic renal failure has yet to be realized. Challenges in maintaining an anticoagulated blood circuit, the typical platform for solute clearance and support of the biological components, have posed a major hurdle in advancement of this technology. This group has developed a Bioartificial Renal Epithelial Cell System (BRECS) capable of differentiated renal cell function while sustained by body fluids other than blood. To evaluate this device for potential use in endâ stage renal disease, a large animal model was established that exploits peritoneal dialysis fluid for support of the biological device and delivery of cell therapy while providing uraemic control. Anephric sheep received a continuous flow peritoneal dialysis (CFPD) circuit that included a BRECS. Sheep were treated with BRECS containing 1 à  108 renal epithelial cells or acellular sham devices for up to 7 days. The BRECS cell viability and activity were maintained with extracorporeal peritoneal fluid circulation. A systemic immunological effect of BRECS therapy was observed as cellâ treated sheep retained neutrophil oxidative activity better than shamâ treated animals. This model demonstrates that use of the BRECS within a CFPD circuit embodies a feasible approach to a sustainable and effective wearable bioartificial kidney. Copyright © 2016 John Wiley & Sons, Ltd.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140038/1/term2206.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/140038/2/term2206_am.pd

A Biomimetic Membrane Device That Modulates the Excessive Inflammatory Response to Sepsis

OBJECTIVE: Septic shock has a clinical mortality rate approaching fifty percent. The major clinical manifestations of sepsis are due to the dysregulation of the host's response to infection rather than the direct consequences of the invading pathogen. Central to this initial immunologic response is the activation of leukocytes and microvascular endothelium resulting in cardiovascular instability, lung injury and renal dysfunction. Due to the primary role of leukocyte activation in the sepsis syndrome, a synthetic biomimetic membrane, called a selective cytopheretic device (SCD), was developed to bind activated leukocytes. The incorporation of the SCD along an extracorporeal blood circuit coupled with regional anticoagulation with citrate to lower blood ionized calcium was devised to modulate leukocyte activation in sepsis. DESIGN: Laboratory investigation. SETTING: University of Michigan Medical School. SUBJECTS: Pigs weighing 30-35 kg. INTERVENTIONS: To assess the effect of the SCD in septic shock, pigs were administered 30×10(10) bacteria/kg body weight of Escherichia coli into the peritoneal cavity and within 1 hr were immediately placed in an extracorporeal circuit containing SCD. MEASUREMENTS AND MAIN RESULTS: In this animal model, the SCD with citrate compared to control groups without the SCD or with heparin anticoagulation ameliorated the cardiovascular instability and lung sequestration of activated leukocytes, reduced renal dysfunction and improved survival time compared to various control groups. This effect was associated with minimal elevations of systemic circulating neutrophil activation. CONCLUSIONS: These preclinical studies along with two favorable exploratory clinical trials form the basis of an FDA-approved investigational device exemption for a pivotal multicenter, randomized control trial currently underway

Outcomes after non-operative management of perforated diverticular disease: a population-based cohort study

Abstract Background The management of perforated diverticular disease has changed in the past 10 years with a move towards less surgical intervention. This population-based cohort study aimed to define the risk of death and readmission following non-operative management of perforated diverticular disease. Methods Patients diagnosed with perforated diverticular disease and managed without surgery were identified from the linked Clinical Practice Research Datalink and Hospital Episode Statistics data from 2000 to 2013. The outcomes were 1-year case fatality, readmissions, and surgery at readmission. Results In total, 880 patients with perforated diverticular disease were managed without surgery, comprising 523 women (59.4 per cent). The 1-year case fatality rate was 33.2 per cent (293 of 880). The majority of deaths occurred in the first 90 days after the index admission, with a 90-day case fatality rate of 28.8 per cent. The 90-day survival rate varied by age, and was 97.2 per cent among those aged less than 65 years, compared with 85.0 per cent for those aged between 65 and 74 years, and 47.7 per cent in those at least 75 years old. Of 767 patients discharged from hospital, 250 (32.6 per cent) were readmitted (47 elective, 6.1 per cent; 203 emergency, 26.5 per cent) during a median of 1.6 (i.q.r. 0.1–3.9) years of follow-up, with similar proportions in each age category. In the first year of follow-up, only 5.1 per cent of patients required surgery, of whom 16 of 767 (2.1 per cent) required elective and 23 (3.0 per cent) emergency operation. Conclusion Non-operative management of perforated diverticulitis in those aged less than 65 years is feasible and safe. Reintervention rates following conservative management were low across all age categories

Predictors of persistent postoperative opioid use following colectomy: a population‐based cohort study from England

This retrospective cohort study on adults undergoing colectomy from 2010 to 2019 used linked primary (Clinical Practice Research Datalink), and secondary (Hospital Episode Statistics) care data to determine the prevalence of persistent postoperative opioid use following colectomy, stratified by pre-admission opioid exposure, and identify associated predictors. Based on pre-admission opioid exposure, patients were categorised as opioid-naïve, currently exposed (opioid prescription 0–6 months before admission) and previously exposed (opioid prescription within 7–12 months before admission). Persistent postoperative opioid use was defined as requiring an opioid prescription within 90 days of discharge, along with one or more opioid prescriptions 91–180 days after hospital discharge. Multivariable logistic regression analyses were conducted to obtain odds ratios for predictors of persistent postoperative opioid use. Among the 93,262 patients, 15,081 (16.2%) were issued at least one opioid prescription within 90 days of discharge. Of these, 6791 (45.0%) were opioid-naïve, 7528 (49.9%) were currently exposed and 762 (5.0%) were previously exposed. From the whole cohort, 7540 (8.1%) developed persistent postoperative opioid use. Patients with pre-operative opioid exposure had the highest persistent use: 5317 (40.4%) from the currently exposed group; 305 (9.8%) from the previously exposed group; and 1918 (2.5%) from the opioid-naïve group. The odds of developing persistent opioid use were higher among individuals who used long-acting opioid formulations in the 180 days before colectomy than those who used short-acting formulations (odds ratio 3.41 (95%CI 3.07–3.77)). Predictors of persistent opioid use included: previous opioid exposure; high deprivation index; multiple comorbidities; use of long-acting opioids; white race; and open surgery. Minimally invasive surgical approaches were associated with lower odds of persistent opioid use and may represent a modifiable risk factor

A systematic review of studies measuring and reporting hearing aid usage in older adults since 1999: a descriptive summary of measurement tools

Objective: A systematic review was conducted to identify and quality assess how studies published since 1999 have measured and reported the usage of hearing aids in older adults. The relationship between usage and other dimensions of hearing aid outcome, age and hearing loss are summarised. Data sources: Articles were identified through systematic searches in PubMed/MEDLINE, The University of Nottingham Online Catalogue, Web of Science and through reference checking. Study eligibility criteria: (1) participants aged fifty years or over with sensori-neural hearing loss, (2) provision of an air conduction hearing aid, (3) inclusion of hearing aid usage measure(s) and (4) published between 1999 and 2011. Results: Of the initial 1933 papers obtained from the searches, a total of 64 were found eligible for review and were quality assessed on six dimensions: study design, choice of outcome instruments, level of reporting (usage, age, and audiometry) and cross validation of usage measures. Five papers were rated as being of high quality (scoring 10–12), 35 papers were rated as being of moderate quality (scoring 7–9), 22 as low quality (scoring 4–6) and two as very low quality (scoring 0–2). Fifteen different methods were identified for assessing the usage of hearing aids. Conclusions: Generally, the usage data reviewed was not well specified. There was a lack of consistency and robustness in the way that usage of hearing aids was assessed and categorised. There is a need for more standardised level of reporting of hearing aid usage data to further understand the relationship between usage and hearing aid outcomes