Method and apparatus for reducing the drag of flows over surfaces

An apparatus, and its accompanying method, for reducing the drag of flows over a surface includes arrays of small disks and sensors. The arrays are embedded in the surface and may extend above, or be depressed below, the surface, provided they remain hydraulically smooth either when operating or when inactive. The disks are arranged in arrays of various shapes, and spaced according to the cruising speed of the vehicle on which the arrays are installed. For drag reduction at speeds of the order of 30 meters/second, preferred embodiments include disks that are 0.2 millimeter in diameter and spaced 0.4 millimeter apart. For drag reduction at speeds of the order of 300 meters/second, preferred embodiments include disks that are 0.045 millimeter in diameter and spaced 0.09 millimeter apart. Smaller and larger dimensions for diameter and spacing are also possible. The disks rotate in the plane of the surface, with their rotation axis substantially perpendicular to the surface. The rotating disks produce velocity perturbations parallel to the surface in the overlying boundary layer. The sensors sense the flow at the surface and connect to control circuitry that adjusts the rotation rates and duty cycles of the disks accordingly. Suction and blowing holes can be interspersed among, or made coaxial with, the disks for creating general three-component velocity perturbations in the near-surface region. The surface can be a flat, planar surface or a nonplanar surface, such as a triangular riblet surface. The present apparatus and method have potential applications in the field of aeronautics for improving performance and efficiency of commercial and military aircraft, and in other industries where drag is an obstacle, including gas and oil delivery through long-haul pipelines

The interest of gait markers in the identification of subgroups among fibromyalgia patients

<p>Abstract</p> <p>Background</p> <p>Fibromyalgia (FM) is a heterogeneous syndrome and its classification into subgroups calls for broad-based discussion. FM subgrouping, which aims to adapt treatment according to different subgroups, relies in part, on psychological and cognitive dysfunctions. Since motor control of gait is closely related to cognitive function, we hypothesized that gait markers could be of interest in the identification of FM patients' subgroups. This controlled study aimed at characterizing gait disorders in FM, and subgrouping FM patients according to gait markers such as stride frequency (SF), stride regularity (SR), and cranio-caudal power (CCP) which measures kinesia.</p> <p>Methods</p> <p>A multicentre, observational open trial enrolled patients with primary FM (44.1 ± 8.1 y), and matched controls (44.1 ± 7.3 y). Outcome measurements and gait analyses were available for 52 pairs. A 3-step statistical analysis was carried out. A preliminary single blind analysis using k-means cluster was performed as an initial validation of gait markers. Then in order to quantify FM patients according to psychometric and gait variables an open descriptive analysis comparing patients and controls were made, and correlations between gait variables and main outcomes were calculated. Finally using cluster analysis, we described subgroups for each gait variable and looked for significant differences in self-reported assessments.</p> <p>Results</p> <p>SF was the most discriminating gait variable (73% of patients and controls). SF, SR, and CCP were different between patients and controls. There was a non-significant association between SF, FIQ and physical components from Short-Form 36 (p = 0.06). SR was correlated to FIQ (p = 0.01) and catastrophizing (p = 0.05) while CCP was correlated to pain (p = 0.01). The SF cluster identified 3 subgroups with a particular one characterized by normal SF, low pain, high activity and hyperkinesia. The SR cluster identified 2 distinct subgroups: the one with a reduced SR was distinguished by high FIQ, poor coping and altered affective status.</p> <p>Conclusion</p> <p>Gait analysis may provide additional information in the identification of subgroups among fibromyalgia patients. Gait analysis provided relevant information about physical and cognitive status, and pain behavior. Further studies are needed to better understand gait analysis implications in FM.</p

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Irinotecan-induced mucositis is associated with changes in intestinal mucins

PurposeMucositis is a major oncological problem, caused by the cytotoxic effects of cancer chemotherapy and radiotherapy. Irinotecan is used to treat a variety of solid tumours, through the inhibition of DNA topoisomerase I and is linked with severe mucositis and diarrhoea. Mucus production appears to be increased, which may contribute to the development of diarrhoea.MethodsDark agouti rats were treated with irinotecan, and tissues collected at several time points up to 72 h. Goblet cells and mucin secretion were investigated, as well as mucin expression (Muc2 and Muc4) and kruppel-like factor (Klf) 4 using immunohistochemistry in the gastrointestinal tract. Both goblet cells and cells positive for Muc expression were counted, and analysed statistically using the Mann-Whitney U test with Bonferroni correction.ResultsGoblet cells decreased significantly after irinotecan treatment. However, mucin secretion increased. Mucin expression changed significantly after treatment. Muc2 and Muc4 decreased significantly in the villi of the jejunum after treatment, Muc2 and Muc4 decreased significantly in the crypts. Muc2 decreased significantly in the colon.ConclusionsIrinotecan causes an increase in mucin secretion and a net decrease in mucin-producing goblet cells, and the expression of Muc2 and Muc4 in the gastrointestinal tract is altered following treatment. Increased mucin secretion is likely to be related to altered mucin expression, and may contribute to chemotherapy-induced diarrhoea.Andrea M. Stringer, Rachel J. Gibson, Richard M. Logan, Joanne M. Bowen, Ann S. J. Yeoh, Jessica Laurence and Dorothy M. K. Keef