Flow control and high-lift performance for flying-wing manned Combat Air Vehicle Configurations by inserting lots

The objectives of the present study on Unmanned Combat Air Vehicles (UCAVs) are two-fold: first to control the flow by inserting leading-edge and cross-flow slots and analysing the viscous flow development over the outer panels of a flying-wing configuration to maximise the performance of the elevons control surfaces; second to predict high-lift performance particularly the maximum-lift characteristics. This is demonstrated using a variety of inviscid Vortex Lattice Method (VLM) and Euler, and viscous CFD Reynolds Averaged Navier-Stokes (RANS) methods. The computational results are validated against experiment measured in a wind tunnel. Two flying-wing planforms are considered based around a generic 40 ̊ edge-aligned configuration. The VLM predicts a linear variation of lift and pitching moment with incidence angle, and substantially under-predicts the induced drag. Results obtained from RANS and Euler agree well with experiment

Studies on uricase induction in certain bacteria

Three strains of Proteus vulgaris and two Streptomyces species were screened for inducible uricase formation. P. vulgaris (1753 and B-317-C), Streptomyces graminofaciens and S.albidoflavus showed inducible uricase activity, but P. vulgaris U7 did not show activity under the experimental conditions tested. Different amounts of constitutive and induced uricase were obtained by the four organisms using different culture media. The enzyme was induced in the producing organisms by different concentrations of different inducers, and uric acid was the mostpotent inducer. Using the optimal concentration of uric acid as inducer, the conditions of uricase induction in the test organisms were optimized. In P. vulgaris strains (1753 and B-317-C), theincubation temperature of 37 ºC, initial pH of culture media of 7 and agitation rate of 180 rpm, showed the highest level of uricase induction. In the two Streptomyces species, the uricase induction was optimized at 28 ºC incubation temperature and pH 7. The agitation rate of 200 and 220 rpm showed the highest induction activity in Streptomyces graminofaciens and S. albidoflavus, respectively. The highest levels of induced uricase were obtained at induction times of 140 min, 140 min, 42 h and 36 h in P. vulgaris 1753, B-317-C, Streptomyces graminofaciens and S. albidoflavus, respectively. The uricase was present as cell-bound enzyme in the producing organisms and no activity was recorded in the culture supernatants

Emergency Operations for Bleeding Duodenal Ulcer:A simple option to consider: Case Report

We report a 46 years-old man who had severe bleeding from a posterior duodenal ulcer (DU) that was diagnosed but could not be treated endoscopically in another health facility. He went into shock as he was being admitted to the casualty at Khartoum North Teaching Hospital (KNTH). His haemoglobin (Hb) dropped to five gram/dl. He required resuscitation and transfusion of six units of blood overnight. Emergency surgery was performed. Over sewing (OS) of the ulcer was done and the stenosed first part of duodenum was closed transversely (pyloroplasty). No acid-reducing procedure (ARP) was done. The patient received anti- helicobacter therapy via the intravenous route preoperatively and continued postoperatively. This was later given orally after he started taking by mouth. He made an uneventful recovery with no recurrence of bleeding and was discharged home one week latter. Endoscopy was done at KNTH six weeks later. This showed complete healing of the ulcer with no evidence of Helicobacter pylori in the biopsies taken. We found simple OS of the bleeding DU together with anti-helicobacter therapy safe, efficient, and not associated with re-bleeding. We discuss the rationale of this simple treatment. We propose the need for a randomized controlled study comparing it with acid-reducing procedure (ARP) as options in the surgical treatment of bleeding DU. Keywords: Bleeding duodenal ulcer, Emergency surgical operations, Peptic ulcer, Helicobacter pylori, Anti-helicobacter therapy, Sudan Journal of Medical Science Vol. 3 (4) 2008: pp. 339-34

Heavy metal speciation and their accumulation in sediments of Lake Burullus, Egypt

Several sediment samples in Lake Burullus have been affected by the discharges of heavy metals through different drains. The study aimed to analyze the chemical speciation of these metals. In particular, the chemical forms of Cd, Cu, Fe, Mn, Pb and Zn in sediments collected in spring season were studied using a sequential chemical extraction method. In general, all the elements recorded highest concentrations in the area near the discharge point. The data indicated that, the sediments were under a wide variety of environmental conditions ranging from oxic to fully anoxic conditions. Owing a wide variety of grain sizes and organic matter, these metals showed the order of abundance: Fe > Mn > Zn > Cu > Cd > Pb. Significant correlations between iron with clay, organic carbon and manganese concentrations were calculated as (r=0.685, 0.581 and 0.610, P= 0.05), respectively. This gives an idea about association of iron and manganese as main compositions of clays. In the mean time, it showed insignificant relation with total carbonate and all phosphorus forms. The metal speciation characterizes the degree to which they are potentially labile or bioavailability. It gives different fraction ratios depending on binding and sediment origin.Key words: Heavy metals, chemical speciation, sediments, Burullus, Lake

HbA1c as a marker to reduce lower limb amputation in patients with type 2 diabetes mellitus

Background: Diabetes mellitus is one of the most serious and prevalent chronic diseases worldwide. One of the most common complications of diabetes in the lower extremity is the diabetic foot ulcer which is the precursor to ~85% of lower extremity amputations in persons with diabetes. Materials and Subjects: This is a case- control study which was carried out at Jabir Abu-Aliz Specialized Center, Khartoum State, Sudan between October 2006 and April 2007. Forty type 2 diabetes cases with septic foot (group 1 cases), 40 type 2 diabetes cases without septic foot (group 2 cases), and 40 healthy controls participated in this study. Their demographic data were collected. Serum HbA1c levels were estimated by affinity chromatography method. Results: The level of HbA1c was 9.947±1.40%, 7.908±0.45% and 6.462±0.07%. in group 1, group 2, and the healthy control respectively. There was significant increase in percentage level of HbA1c in group 1 cases compared to group 2 cases and healthy control (p = 0.002, 0.001 respectively). We found very low correlation between fasting blood sugar and HbA1c in group 1 cases (r = + 0.331; p=0.042). Conclusion: This study indicates that the progression to the complication of foot ulcer in type 2 diabetic patients was correlated to the level of HbAlc. These data may suggest a beneficial effect of considering measurement of HbA1c as a routine test especially for elderly diabetic patients with diabetes for long period. This may help to maintain blood glucose levels in the normal or near normal range and to provide an opportunity for patients to live out their normal life expectancies with minimal complications. Keywords: glycohemoglobin, neuropathy, septic foot, glycemic control.Sudan Journal of Medical Sciences Vol. 3 (3) 2008: pp. 227-23

Continuous belief functions and α-stable distributions

International audienceThe theory of belief functions has been formalized in continuous domain for pattern recognition. Some applications use assumption of Gaussian models. However, this assumption is reductive. Indeed, some data are not symmetric and present property of heavy tails. It is possible to solve these problems by using a class of distributions called α-stable distributions. Consequently, we present in this paper a way to calculate pignistic probabilities with plausibility functions where the knowledge of the sources of information is represented by symmetric α-stable distributions. To validate our approach, we compare our results in special case of Gaussian distributions with existing methods. To illustrate our work, we generate arbitrary distributions which represents speed of planes and take decisions. A comparison with a Bayesian approach is made to show the interest of the theory of belief functions

Regionalizing healthcare: a vision for transforming Lebanon into a regional academic hub

<p>Abstract</p> <p>Background</p> <p>Lebanon suffers from a large scale emigration of physicians coupled with an oversaturation of the physician job market. Lebanon is currently witnessing an expansion of its medical education capacity with the establishment of new private medical schools, raising the fears of a worsening market oversaturation.</p> <p>Discussion</p> <p>The neighboring Arabian Gulf countries are suffering from a serious shortage of clinicians and academicians. In spite of their enormous investments in educational, clinical and research collaborative initiatives with some of the most renowned North American medical schools and institutions, their ability to recruit and retain highly qualified clinicians and academicians remains a major challenge. Lebanese universities have the opportunity to establish triangular collaborations with the Gulf regional medical centers and their North American partners. They could achieve this goal by tapping into the globalized and high quality Lebanese physician workforce and consequently regionalize healthcare delivery in the Middle East.</p> <p>Summary</p> <p>By recruiting its globalized and high quality physician workforce to establish collaborations with the Gulf regional, Lebanon could become a regional "academic hub".</p

Holographic two-point functions for 4d log-gravity

We compute holographic one- and two-point functions of critical higher-curvature gravity in four dimensions. The two most important operators are the stress tensor and its logarithmic partner, sourced by ordinary massless and by logarithmic non-normalisable gravitons, respectively. In addition, the logarithmic gravitons source two ordinary operators, one with spin-one and one with spin-zero. The one-point function of the stress tensor vanishes for all Einstein solutions, but has a non-zero contribution from logarithmic gravitons. The two-point functions of all operators match the expectations from a three-dimensional logarithmic conformal field theory.Comment: 35 pages; v2: typos corrected, added reference; v3: shorter introduction, minor changes in the text in section 3, added reference; published versio

Neonatal outcomes among twins following assisted reproductive technology: An Australian population-based retrospective cohort study

© 2018 The Author(s). Background: While their incidence is on the rise, twin pregnancies are associated with risks to the mothers and their babies. This study aims to investigate the likelihood of adverse neonatal outcomes of twins following assisted reproductive technology (ART) compared to non-ART twins. Methods: A retrospective population study using the Australian National Perinatal Data Collections (NPDC) which included 19,662 twins of ≥20weeks gestational age or≥400g birthweight in Australia. Maternal outcomes and neonatal outcomes (preterm birth, low birth weight, resuscitation and neonatal death) were compared. Generalized Estimating Equations were used to assess the likelihood of any neonatal outcomes, with adjusted odds ratio (AOR) and 95% confidence intervals (CI) presented. Weinberg's differential rule was used to estimate monozygotic twin rate. Results: ART mothers were 3.3years older than non-ART mothers. The rates of pregnancy-induced hypertension and gestational diabetes were significantly higher for ART mothers than non-ART mothers (12.2% vs. 8.4%, p< 0.01) and (9.7% vs. 7.5%, p< 0.01) respectively. The incidence of monozygotic twins was 2.0% for ART twins and 1.1% for non-ART twins. Compared with non-ART twins, ART twins had higher rates of preterm birth (AOR 1.13, 95% CI: 1.05-1.22), low birth weight (AOR 1.13, 95% CI: 1.05-1.22), and resuscitation (AOR 1.26, 95% CI: 1.17-1.36). Liveborn ART twins had 28% (AOR 1.28, 95% CI 1.09-1.50) increased odds of having any adverse neonatal outcome compared to liveborn non-ART twins, especially for opposite-sex ART twins (AOR 1.42, 95% CI 1.11-1.82). Conclusion: As ART twins had higher rates of adverse outcome, special prenatal care is recommended. Couples accessing ART should be fully informed of the risk of adverse outcome of twin pregnancies

The impact of obesity on time spent with the provider and number of medications managed during office-based physician visits using a cross-sectional, national health survey

<p>Abstract</p> <p>Background</p> <p>Obesity is associated with morbidity, mortality, and increased health care costs. Few studies have examined the impact of obesity on outpatient office visits. The purpose of this study was to determine if outpatient visits by obese persons required more time with the provider and more prescription medication management compared to visits made by non-obese persons.</p> <p>Methods</p> <p>Obesity status was determined for 9,280 patient visits made by persons aged 18 years or older in the 2006 National Ambulatory Medical Care Survey. Multivariate analyses compared obese and non-obese visits, stratified by sex, for duration of the visit and the number of medications mentioned at the visit.</p> <p>Results</p> <p>Average duration of visit was higher among visits with patients determined to be obese. However, these differences were not considered significant after statistical testing. Visits made by obese female patients were significantly more likely to involve more than two prescription medications (OR 1.26, 95% CI 1.05 - 1.51) and visits made by obese male patients were significantly more likely to involve more than two prescription medications (OR 1.46, 95% CI 1.16 - 1.83) as compared to visits made by non-obese patients.</p> <p>Conclusion</p> <p>Time spent with the provider was found to be greater among visits with obese patients, but not significantly different from visits with non-obese patients. The number of medications for each visit was found to be significantly greater for visits where the patient was considered to be obese. Increased time for the visit and increased numbers of medication for each visit translate into increased costs. These findings document the impact of obesity on our health care system and have great implications on medical care cost and planning.</p