Geometry of intensive scalar dissipation events in turbulence

Maxima of the scalar dissipation rate in turbulence appear in form of sheets and correspond to the potentially most intensive scalar mixing events. Their cross-section extension determines a locally varying diffusion scale of the mixing process and extends the classical Batchelor picture of one mean diffusion scale. The distribution of the local diffusion scales is analysed for different Reynolds and Schmidt numbers with a fast multiscale technique applied to very high-resolution simulation data. The scales take always values across the whole Batchelor range and beyond. Furthermore, their distribution is traced back to the distribution of the contractive short-time Lyapunov exponent of the flow.Comment: 4 pages, 5 Postscript figures (2 with reduced quality

Multigrid Analysis of Scattering by Large Planar Structures

Abstract Fast iterative analysis of two-dimensional scattering by a large but finite array of perfectly conducting strips requires efficient evaluation of the electric field. We present a novel multigrid algorithm that carries out this task in CN computer operations, where C depends logarithmically on the desired accuracy in the field, and N is the number of spatial gridpoints. Numerical results are presented, and extensions of the algorithm are discussed

Distribution of bovine Fasciola gigantica (Cobbold, 1885) in the district des Savanes, northern Côte d'Ivoire

Fascioliasis, caused by an infection with liver flukes of the genus Fasciola, is an important disease of livestock in most parts of the world. However, little is known about the distribution of fascioliasis in sub-Saharan Africa. We report results of a cross-sectional study conducted in 2014 in the district des Savanes in the northern part of Cote d'Ivoire. We obtained 275 livers from bovine suspected with fascioliasis and 51 unsuspected livers from 24 slaughterhouses. Livers were dissected using a standard operating procedure and all Fasciola gigantica flukes were removed from the tissues of the liver and the biliary ducts. We found F. gigantica in 125 livers from bovines suspected with fascioliasis (45.5%) in 10 departments of the district des Savanes. Among the unsuspected livers, five were positive for F. gigantica (9.8%). The distribution of fascioliasis showed considerable spatial heterogeneity, both at regional (ranging from 18.0% to 52.3%) and departmental level (ranging from 14.3% to 64.0%). Poro region was the most affected (52.3%) with a relatively homogeneous distribution. The departments most affected by fascioliasis were M'Bengue (64.0%), Sinematiali (62.1%) and Ferkessedougou (52.9%). Our study confirms that fascioliasis is an important veterinary disease in the northern part of Cote d'Ivoire, and hence, high-risk areas need to be targeted for prevention and control measures

Efficacy of triclabendazole and albendazole against Fasciola spp. infection in cattle in Côte d'Ivoire: a randomised blinded trial

Triclabendazole is the anthelminthic of choice for the treatment of fascioliasis, however, it is not yet registered in many countries. Therefore, we investigated the efficacy of a single-dose of triclabendazole (12 mg/kg) or albendazole (15 mg/kg) against Fasciola spp. infection in cattle on farms in the northern part of Cote d'Ivoire in a randomized clinical trial. Faecal samples were obtained from 196 cattle, of which 155 (79.1%) were found positive for Fasciola spp. by the sedimentation technique. Cattle infected with Fasciola spp. were randomly allocated (3:3:1) to receive triclabendazole (n=66), albendazole (n=67) or left untreated to serve as control (n=22). Follow-up faecal samples were collected on days 21, 28, 90 and 188 post-treatment. No adverse events were observed as reported by the farmer in any of the treatment groups. The proportion of non-egg shedding cattle (PNES), assessed at day 21 (primary outcome), was significantly higher in cattle treated with triclabendazole (95.4%) compared to those receiving albendazole (70.3%; odds ratio [OR] 0.11, 95% confidence interval [CI] 0.03-0.39, p <0.001). The egg reduction rate (ERR) expressed as number of eggs per gram of faeces (epg), a secondary endpoint assessed at day 21 post-treatment, was significantly higher in the triclabendazole arm (arithmetic mean (AM) ERR=99.8%) than in the albendazole arm (AM ERR=92.2%), with a difference of 7.6%-points (95% CI: 0.9-14.5%-points, p=0.03). Reinfection rates at days 90 and 188 post-treatment (secondary endpoint) were lower in the triclabendazole arm (5.3% and 18.5%) compared to the albendazole arm (23.5% and 33.3%). This is the first report of efficacy of triclabendazole against Fasciola spp. in naturally infected cattle in Cote d'Ivoire. Our results confirm that triclabendazole is the most effective treatment of fascioliasis and therefore, should be considered for the control of livestock fascioliasis; if resources allow in combination with intermediate host snail control and raising farmers awareness of pasture and livestock management to avoid reinfection

The Abnormal Contralateral Atrioventricular Valve in Mitral and Tricuspid Atresia in Neonates: An Echocardiographic Study

Abnormalities of the mitral valve (MV) or the tricuspid valve (TV) morphology and/or function in patients with functional single ventricle may result in early morbidity and death. The purpose of this study was to determine the incidence of contralateral atrioventricular valve (AVV) pathologies in mitral valve atresia (MA) and tricuspid valve atresia (TA). We retrospectively reviewed the echocardiographic data of 50 neonates with MV and 20 with TA. Appearance of the papillary muscles, chordae tendinae, and valve leaflets was assessed. AVV regurgitation was semiquantitated by color-flow Doppler and the AVV annulus diameter was measured and indexed to body surface area. MV abnormalities were found in 9 of 20 (45%) of patients with TA. The MV was myxomatous in 9 patients, the leaflets were redundant in 5 patients, and prolapsing occurred in 4 patients. Mild regurgitation was found in 2 patients. In 18 of 20 (90%) patients MV annulus size was larger than 95% of predicted normal values. TV abnormalities were found in 12 of 50 (24%) patients with MA. The TV was myxomatous in 4 patients, prolapsing in 2, and redundant in 3, and moderate TV regurgitation was found in 3 patients. In 29 of 50 (58%) patients TV annulus size was larger than 95% of predicted normal values. Contralateral AVV abnormalities in tricuspid and mitral valve atresia are common and should be assessed carefully before surgical procedures.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42381/1/246-20-3-200_20n3p200.pd

Infectious diseases in a Nicaraguan refugee camp in Costa Rica

Artículo científico -- Universidad de Costa Rica. Instituto de Investigaciones en Salud, 1989Some Nicaraguans living in Costa Rica are in refugee camps. The types and rates of infectious diseases in the Pueblo Nuevo refugee camp were measured by examining medical records for 1985 and performing stool and blood testing. The incidence of infections was 320 episodes per 1000 persons per year. Respiratory infections represented 63% of all illnesses and pulmonary tuberculosis was high. Malaria was not found in blood samples and no childhood illnesses preventable by immunizations were recorded in the records. intestinal parasites were found in 565 of the persons examined, considerably higher than the 153/4 prevalence noted in surveys of Costa Rica as a whole. Trichuris trichlura was found in 40 To of the positive stool samples. The deficient hygienic conditions and overcrowding in the camp are responsible for the high rates of infections and the continued presence of infections many of which probably were acquired in Nicaragua. Improvement of hygienic conditions can be accomplished by involving the refugees in education, cleaning and identifying problem areas. Adequate sanitation and improved water supply, and reducing overcrowding are also recommended.Universidad de Costa Rica. Instituto de Investigaciones en Salud.Columbia University College of Physicians and Surgeons. New YorkUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto de Investigaciones en Salud (INISA

Prevalence and distribution of livestock schistosomiasis and fascioliasis in Côte d'Ivoire: results from a cross-sectional survey

BACKGROUND: Schistosoma and Fasciola are zoonotic parasites of public health and veterinary importance. However, while the epidemiology of schistosomiasis in humans is well studied, little is known about fascioliasis and schistosomiasis in livestock in Cote d'Ivoire. This study aimed to determine the prevalence and the distribution of livestock schistosomiasis and fascioliasis across Cote d'Ivoire. In 2018, we conducted a cross-sectional survey in abattoirs and farms in 13 departments of Cote d'Ivoire. In abattoirs, the mesenteric veins and livers of slaughtered cattle, sheep and goats were examined for adult Schistosoma and Fasciola flukes. Faeces from live cattle, goats and sheep were collected and examined for Schistosoma and Fasciola eggs using a sedimentation technique. RESULTS: A total of 386 cattle, 174 goats and 151 sheep from abattoirs and 435 cattle, 22 goats and 176 sheep from farms were sampled. The observed prevalence of schistosomiasis was higher in slaughtered animals. Fascioliasis was more prevalent in farm animals. The prevalence of schistosomiasis in slaughtered cattle varied between 5.9% (95% confidence interval (CI): 0.7-19.7%) and 53.3% (95% CI: 37.9-68.3%) with the highest prevalence observed in Ouangolodougou in the North. Cattle from farms had a relatively low prevalence of schistosomiasis, with the highest prevalence found in Ouangolodougou (2.4%, 95% CI: 0.7-6.1%). The prevalence of fascioliasis varied considerably from one department to another, ranging from nil (95% CI: 0.0-18.5%) to 50.8% (95% CI: 43.4-58.2%), with the highest prevalence found in farm cattle in Dikodougou in the North. Sheep and goats had a lower prevalence of schistosomiasis and fascioliasis than cattle. In slaughtered animals, cattle aged 4 years and older were at highest risk for schistosomiasis (odds ratio (OR): 2.4; 95% CI: 1.0-5.6) and fascioliasis (OR: 2.1; 95% CI: 1.1-3.9). In farm animals, male cattle had higher odds of being infected with Schistosoma (OR: 4.3; 95% CI: 0.7-26.9) than females. CONCLUSIONS: Our study confirms that schistosomiasis and fascioliasis are endemic in livestock across Cote d'Ivoire. A strategic control programme should be considered, especially for cattle, including providing drinking water in troughs to reduce faecal contamination of water sources by cattle

Development of correlations for describing solute transfer into acyclic alcohol solvents based on the Abraham model and fragment-specific equation coefficients

This article discusses the development of correlations for describing solute transfer into acyclic alcohol solvents based on the Abraham model and fragment-specific equation coefficients