Serrated trailing edges for improving lift and drag characteristics of lifting surfaces

An improvement in the lift and drag characteristics of a lifting surface is achieved by attaching a serrated panel to the trailing edge of the lifting surface. The serrations may have a saw-tooth configuration, with a 60 degree included angle between adjacent serrations. The serrations may vary in shape and size over the span-wise length of the lifting surface, and may be positioned at fixed or adjustable deflections relative to the chord of the lifting surface

Revision of Laparoscopic Adjustable Gastric Banding: Success or Failure?

BACKGROUND: Laparoscopic adjustable gastric banding (LAGB) is a safe and frequently performed bariatric procedure. Unfortunately, re-operations are often necessary. Reports on the success of revisional procedures are scarce and show variable results, either supporting or declining the idea of revising LAGB. This study describes a large cohort of re-operations after failed LAGB to determine the success of revision. METHODS: By use of a prospective cohort, all LAGB revisions performed between 1996 and 2008 were identified. From 301 primary LAGB procedures in our centre, 43 patients (14.3%) required a band revision. In addition, 51 patients were referred from other centres. Our analysis included in total 94 patients with a mean follow-up period of 38 months after revision. RESULTS: Revision was mainly necessary due to anterior slippage (46%) and symmetrical pouch dilatation (36%), which could be resolved by replacing (70%) or refixating the band (27%). Weight loss significantly increased after revision (excess BMI loss (EBMIL), 37.2 +/- 36.3% versus 47.5 +/- 30.4%, P < 0.05). After revision, 23 patients (24%) needed a second re-operation. Patients converted to other procedures (16%) during the second re-operation showed larger weight loss than the revised group (EBMIL, 64.3 +/- 28.1% versus 44.3 +/- 28.7%, P < 0.05). CONCLUSIONS: We report on a large cohort of LAGB revisions with 38 months of follow-up. Revision of failed LAGB by either refixation or replacement of the band is successful and further increases weight loss

Brown Adipose Tissue in Morbidly Obese Subjects

BACKGROUND: Cold-stimulated adaptive thermogenesis in brown adipose tissue (BAT) to increase energy expenditure is suggested as a possible therapeutic target for the treatment of obesity. We have recently shown high prevalence of BAT in adult humans, which was inversely related to body mass index (BMI) and body fat percentage (BF%), suggesting that obesity is associated with lower BAT activity. Here, we examined BAT activity in morbidly obese subjects and its role in cold-induced thermogenesis (CIT) after applying a personalized cooling protocol. We hypothesize that morbidly obese subjects show reduced BAT activity upon cold exposure. METHODS AND FINDINGS: After applying a personalized cooling protocol for maximal non-shivering conditions, BAT activity was determined using positron-emission tomography and computed tomography (PET-CT). Cold-induced BAT activity was detected in three out of 15 morbidly obese subjects. Combined with results from lean to morbidly obese subjects (n = 39) from previous study, the collective data show a highly significant correlation between BAT activity and body composition (P<0.001), respectively explaining 64% and 60% of the variance in BMI (r = 0.8; P<0.001) and BF% (r = 0.75; P<0.001). Obese individuals demonstrate a blunted CIT combined with low BAT activity. Only in BAT-positive subjects (n = 26) mean energy expenditure was increased significantly upon cold exposure (51.5±6.7 J/s versus 44.0±5.1 J/s, P = 0.001), and the increase was significantly higher compared to BAT-negative subjects (+15.5±8.9% versus +3.6±8.9%, P = 0.001), indicating a role for BAT in CIT in humans. CONCLUSIONS: This study shows that in an extremely large range of body compositions, BAT activity is highly correlated with BMI and BF%. BAT-positive subjects showed higher CIT, indicating that BAT is also in humans involved in adaptive thermogenesis. Increasing BAT activity could be a therapeutic target in (morbid) obesity

Delayed rhythm control of atrial fibrillation may be a cause of failure to prevent recurrences: reasons for change to active antiarrhythmic treatment at the time of the first detected episode

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Dordt College 2003-2004 Catalog

Academic Catalog for 2003-04https://digitalcollections.dordt.edu/academic_catalogs/1012/thumbnail.jp

Understanding repolarization in the intracardiac unipolar electrogram: A long-lasting controversy revisited

Background: The optimal way to determine repolarization time (RT) from the intracardiac unipolar electrogram (UEG) has been a topic of debate for decades. RT is typically determined by either the Wyatt method or the “alternative method,” which both consider UEG T-wave slope, but differently.Objective: To determine the optimal method to measure RT on the UEG.Methods: Seven pig hearts surrounded by an epicardial sock with 100 electrodes were Langendorff-perfused with selective cannulation of the left anterior descending (LAD) coronary artery and submersed in a torso-shaped tank containing 256 electrodes on the torso surface. Repolarization was prolonged in the non-LAD-regions by infusing dofetilide and shortened in the LAD-region using pinacidil. RT was determined by the Wyatt (tWyatt) and alternative (tAlt) methods, in both invasive (recorded with epicardial electrodes) and in non-invasive UEGs (reconstructed with electrocardiographic imaging). tWyatt and tAlt were compared to local effective refractory period (ERP).Results: With contact mapping, mean absolute error (MAE) of tWyatt and tAlt vs. ERP were 21 ms and 71 ms, respectively. Positive T-waves typically had an earlier ERP than negative T-waves, in line with theory. tWyatt -but not tAlt-shortened by local infusion of pinacidil. Similar results were found for the non-invasive UEGs (MAE of tWyatt and tAlt vs. ERP were 30 ms and 92 ms, respectively).Conclusion: The Wyatt method is the most accurate to determine RT from (non) invasive UEGs, based on novel and historical analyses. Using it to determine RT could unify and facilitate repolarization assessment and amplify its role in cardiac electrophysiology

Full-genome deep sequencing and phylogenetic analysis of novel human betacoronavirus

A novel betacoronavirus associated with lethal respiratory and renal complications was recently identified in patients from several countries in the Middle East. We report the deep genome sequencing of the virus directly from a patient's sputum sample. Our high-throughput sequencing yielded a substantial depth of genome sequence assembly and showed the minority viral variants in the specimen. Detailed phylogenetic analysis of the virus genome (England/Qatar/2012) revealed its close relationship to European bat coronaviruses circulating among the bat species of the Vespertilionidae family. Molecular clock analysis showed that the 2 human infections of this betacoronavirus in June 2012 (EMC/2012) and September 2012 (England/Qatar/2012) share a common virus ancestor most likely considerably before early 2012, suggesting the human diversity is the result of multiple zoonotic events

Maternal health-related quality of life after induction of labor or expectant monitoring in pregnancy complicated by intrauterine growth retardation beyond 36 weeks

Objective: Pregnancies complicated by intrauterine growth retardation (IUGR) beyond 36 weeks of gestation are at increased risk of neonatal morbidity and mortality. Optimal treatment in IUGR at term is highly debated. Results from the multicenter DIGITAT (Disproportionate Intrauterine Growth Intervention Trial At Term) trial show that induction of labor and expectant monitoring result in equal neonatal and maternal outcomes for comparable cesarean section rates. We report the maternal health-related quality of life (HR-QoL) that was measured alongside the trial at several points in time. Methods: Both randomized and non-randomized women were asked to participate in the HR-QoL study. Women were asked to fill out written validated questionnaires, covering background characteristics, condition-specific issues and the Short Form (SF-36), European Quality of Life (EuroQoL 6D3L), Hospital Anxiety and Depression scale (HADS), and Symptom Check List (SCL-90) at baseline, 6 weeks postpartum and 6 months postpartum. We compared the difference scores of all summary measures between the two management strategies by ANOVA. A repeated measures multivariate mixed model wa