Phage typing or CRISPR typing for epidemiological surveillance of Salmonella Typhimurium?

Objective: Salmonella Typhimurium is the most dominant Salmonella serovar around the world. It is associated with foodborne gastroenteritis outbreaks but has recently been associated with invasive illness and deaths. Characterization of S. Typhimurium is therefore very crucial for epidemiological surveillance. Phage typing has been used for decades for subtyping of S. Typhimurium to determine the epidemiological relation among isolates. Recent studies however have suggested that high throughput clustered regular interspaced short palindromic repeats (CRISPR) typing has the potential to replace phage typing. This study aimed to determine the efficacy of highthroughput CRISPR typing over conventional phage typing in epidemiological surveillance and outbreak investigation of S. Typhimurium. Results: In silico analysis of whole genome sequences (WGS) of well-documented phage types of S. Typhimurium reveals the presence of different CRISPR type among strains belong to the same phage type. Furthermore, different phage types of S. Typhimurium share identical CRISPR type. Interestingly, identical spacers were detected among outbreak and non-outbreak associated DT8 strains of S. Typhimurium. Therefore, CRISPR typing is not useful for the epidemiological surveillance and outbreak investigation of S. Typhimurium and phage typing, until it is replaced by WGS, is still the gold standard method for epidemiological surveillance of S. Typhimurium

Why do people prefer traditional bonesetters in Sudan?

Background: In Sudan as in other developing nations, traditional bonesetters play a significant role in primary fracture care. There is widespread belief in our society that TBS are better at fracture treatment than orthodox practitioners. Significant numbers of patients with fractures present first to the traditional bonesetters before coming to the hospital and therefore this mode of care delivery cannot be overlooked in Sudan. Objectives: A prospective study designed to determine the reasons of why a considerable number of people prefer to go to the traditional bonesetters in Sudan.Patients and methods: This prospective two stages study was carried out in two different stages, 1st stage in 2006 targeted general population, and the 2nd stage in the period from May 2009 to September 2009 targeted traditional bonesetters and their patients. In the 1st stage of the study we distributed a predesigned questionnaire to general population, while in the 2nd stage of the study we visited different traditional bonesetter in order to interview them and their visitors and completing the early prepared Performa. We excluded the too elderly patients and children who have nodecisions to choose TBS.Results: In the 1st stage of study the participants were 199 of them, 192 participants responded well to the questionnaire. The reasons why they went to traditional bonesetters were; in 71 participants (37%) was their beliefs, in 27 (14.06%) was due to the low cost, and in 27 (14.06%) was due to fear of plaster. In the 2nd stage of the study 276 participants fulfilled the criteria of the research. The reason why they went to traditional bonesetters; in 63 candidates (22.8%) was their beliefs (P value < 0.003), in 53 (19.2%) was low cost (P value < 0.05), and in 46 (16.7%) was due to fear of cast or amputation. Study included sixteen traditional bonesetters, of them 14 were males and 2 were females. One of them has a bachelor graduation from faculty of sciences. 11 (68.8%) traditional bonesetters accepted the idea of regular training under medical supervision.Conclusion: Despite an adequate number of physicians practising in the region, traditional bonesetters continue to be consulted. Study showed that a belief is the most leading cause of consulting traditional bonesetters, other causes including fear of plaster or amputation and less cost. We recommend that the efficacy of their treatments have to be further assessed.Keywords: Traditional bonesetter (TBS); Beliefs, medical services

Nonlinear centrifugal instabilities in curved free shear layers

Curved free shear layers exist in many engineering problems involving complex flow geometries, such as the backward facing step flow, flows with wall injection, the flow inside side-dump combustors, or flows generated by vertical axis wind turbines, among others. Most of the studies involving centrifugal instabilities have been focused on wall flows where Taylor instabilities between two rotating concentric cylinders or Görtler vortices in boundary layers resulting from the imbalance between centrifugal effects and radial pressure gradients, are generated. Curved free shear layers, however, did not receive sufficient attention. An examination of the stability characteristics and the flow structures associated with curved free shear flows should provide a better understanding of these complex flow problems. In this work, we study the development of Görtler vortices inside a curved shear layer in both the incompressible and compressible regimes using a numerical solution to a parabolized form of the Navier-Stokes equations, in the assumption that the streamwise wavenumber associated with the vortex flow is much smaller than the crossstream wavenumbers. Various results consisting of contour plots of centrifugal instabilites in crossflow planes, and energy and streak amplitude distributions along the streamwise direction are reported and discussed. In addition, we conduct a biglobal stability analysis to study the growth rates and the eigenmodes associated with these flows

Importance of Ethnicity, CYP2B6 and ABCB1 Genotype for Efavirenz Pharmacokinetics and Treatment Outcomes: A Parallel-group Prospective Cohort Study in two sub-Saharan Africa Populations.

We evaluated the importance of ethnicity and pharmacogenetic variations in determining efavirenz pharmacokinetics, auto-induction and immunological outcomes in two African populations. ART naïve HIV patients from Ethiopia (n = 285) and Tanzania (n = 209) were prospectively enrolled in parallel to start efavirenz based HAART. CD4+ cell counts were determined at baseline, 12, 24 and 48 weeks. Plasma and intracellular efavirenz and 8-hydroxyefvairenz concentrations were determined at week 4 and 16. Genotyping for common functional CYP2B6, CYP3A5, ABCB1, UGT2B7 and SLCO1B1 variant alleles were done. Patient country, CYP2B6*6 and ABCB1 c.4036A>G (rs3842A>G) genotype were significant predictors of plasma and intracellular efavirenz concentration. CYP2B6*6 and ABCB1 c.4036A>G (rs3842) genotype were significantly associated with higher plasma efavirenz concentration and their allele frequencies were significantly higher in Tanzanians than Ethiopians. Tanzanians displayed significantly higher efavirenz plasma concentration at week 4 (p<0.0002) and week 16 (p = 0.006) compared to Ethiopians. Efavirenz plasma concentrations remained significantly higher in Tanzanians even after controlling for the effect of CYP2B6*6 and ABCB1 c.4036A>G genotype. Within country analyses indicated a significant decrease in the mean plasma efavirenz concentration by week 16 compared to week 4 in Tanzanians (p = 0.006), whereas no significant differences in plasma concentration over time was observed in Ethiopians (p = 0.84). Intracellular efavirenz concentration and patient country were significant predictors of CD4 gain during HAART. We report substantial differences in efavirenz pharmacokinetics, extent of auto-induction and immunologic recovery between Ethiopian and Tanzanian HIV patients, partly but not solely, due to pharmacogenetic variations. The observed inter-ethnic variations in efavirenz plasma exposure may possibly result in varying clinical treatment outcome or adverse event profiles between populations

Profitability analysis of catfish farming in Suleja local government area of Niger state, Nigeria

The problem of profitability and scale of production of catfish has not been properly addressed. This study was conducted in Suleja Local Government Area of Niger State to assess the profitability of catfish production. Forty (40) catfish farmers were selected from the study area using simple random sampling techniques. Structured questionnaire was used to collect data from the respondents. The analytical tools used include, descriptive statistics, net farm income analysis and profitability ratios and multiple regression functions. The result of the analysis showed that the average total cost per kilogram of fish was N321.23k and the average total revenue per kg of fish was N501.31. This gives a net farm income of N180.08k per kilogram of fish farmed. The study also showed that the sum total of elasticity of variables was less than one (0.994), this indicates that catfish farming in the study area is in stage II, which is the rational stage of production. Double-log functional model was chosen as lead equation. The value of R2 was 0.998. The number of ponds (X1) and number of fingerlings (X3) were significant at 1%, while labour(X5) was significant at 5% levels of significance. The F- ratio of 2964.370 was significant at P (&lt; 0.01). This implies that all the explanatory variables taken together have significance on the dependent variable (Y), the output. Due to expensive nature of flow-through and re-circulatory ponds, earthen ponds were mostly preferred by majority (92.5%) of the fish farmers in the study area. The major problems faced by catfish farmers include; water, high cost of feed and capital.Key Words: cat fish, net farm income, profitability rati

The simultaneous effects of the wetting layer, intense laser and the conduction band non-parabolicity on the donor binding energy in a InAs/GaAs conical quantum dot using the numerical FEM

Using the finite element method, we have performed a systematic study on the ground-state binding energy (  of a donor impurity confined in a  conical quantum dot (CQD) with wetting layer (WL) and a realistic finite confining potential. The simultaneous effect of the applied electric and magnetic fields as well as the influence of an intense laser field have been performed on the Eb within the effective mass approximation. The band non-parabolicity effect is also considered using the energy dependent effective mass approximation. It has been shown that the Eb is highly dependent on the internal and external CQD structure parameters such as radial thickness, height and WL thickness, external electric, magnetic fields and intense laser field. The results we have obtained show that a quite significant contribution of the WL effects on the ground state energy and the Eb has found at small values of the cone radius. In the low confinement regime, the effect of the conduction band non-parabolicity becomes gradually smaller as the value of the cone radius increases and the influence of high-frequency laser increases with the non-parabolicity effect in the regime of small QD radius. Our results are in good agreement with those obtained in the literature

Évaluation des concentrations des sédiments en suspension en aval de deux bassins de sédimentation situés dans deux tourbières exploitées au Nouveau-Brunswick.

La récolte de la tourbe est une industrie en pleine croissance au Canada. Elle est également pratiquée dans plusieurs pays nordiques entre autre pour répondre à la demande dans le domaine de l’horticulture. Toutefois, la récolte de tourbe peut avoir des effets négatifs sur le milieu environnant tels qu’une charge sédimentaire accrue associée à l'eau de drainage provenant des tourbières exploitées qui se déverse dans les cours d’eau et les rivières en aval de la zone récoltée. L'objectif du présent projet est de mener une étude comparative sur l'efficacité des différentes méthodes d'atténuation de la charge sédimentaire produite par les tourbières exploitées et de tester une approche visant à améliorer l'efficacité des bassins de sédimentation. Deux différentes tourbières (Hardwood et Rogersville) au Nouveau-Brunswick, Canada, ont été étudiées, toutes deux exploitées par Premier Horticulture. Un premier objectif spécifique du présent projet était de déterminer si une corrélation existait entre le débit et la concentration de sédiments en suspension (CSS) et entre les précipitations et les CSS pour les deux tourbières. Les autres objectifs consistaient à déterminer si la charge sédimentaire et l'efficacité du bassin de sédimentation était influencée par les activités d'exploitation ou d’entretien. En outre, un bassin de sédimentation a été modifié durant la présente étude et des épis ont été installés afin de vérifier si l’ajout d’une telle structure pouvait améliorer l'efficacité du bassin de sédimentation. Enfin, les données sur les types et la taille des sédiments déposés dans la rivière en aval des bassins de sédimentation ainsi que la teneur en matière organique de ces sédiments ont été recueillies et analysées. La tourbière Hardwood a un bassin de sédimentation dont la dimension est en accord avec les lignes directrices du Nouveau-Brunswick. Trois stations de suivi ont été installées dans la rivière Portage, qui reçoit les eaux de drainage, pendant la période sans glace en 2007 et 2008. La station 1 était située à 2km en aval de la tourbière exploitée, tandis que la station 2 était située à 10 m en aval de la confluence de la rivière East Branch Portage et d’un chenal (dépression) formé par les eaux de drainage de la tourbière exploitée. La station C3 est située à environ 600 m en amont de la station C2 et de toutes les activités opérationnelles durant cette présente étude. Les données ont été recueillies sur ces sites du 11 mai au 9 novembre 2007 et du 28 mai au 1er octobre 2008. La tourbière de Rogersville, un site actif avec un réseau de drainage à grande échelle, possède un bassin de sédimentation de taille qui ne correspond pas aux lignes directrices du Nouveau-Brunswick. Le bassin est situé à environ 78 m en aval de la zone de récolte de tourbe. Sa longueur, de 170 m ainsi que la profondeur de 0.5 m ne correspondent pas aux normes recommandées au Nouveau-Brunswick. Le suivi des sédiments à Rogersville, qui a eu lieu du 27 juin au 25 novembre en 2008 et du 7 mai au 9 décembre en 2009, a été l'une des premières études à mesurer les CSS simultanément à l’entrée et à la sortie du bassin de sédimentation. Les CSS ont été mesurées également dans le cours d’eau récepteur, à 1,16 km en aval du bassin de sédimentation. Des épis ont été installés dans le bassin de sédimentation à la mi-octobre en 2008 pour déterminer si ces structures pouvaient améliorer l'efficacité du bassin en ralentissant l’écoulement. Ces épis sont restés en place pendant le reste de 2008 et tout au long de la période d'étude en 2009 et n'ont jamais été enlevés. Pour le suivi de la sédimentation en aval des bassins, cinq sites ont été équipés de quatre trappes à sédiments chacun pour la tourbière Hardwood et ce durant les deux années de suivi. Quatre sites, avec 3 trappes à sédiments chacun, ont été mis en place pour la tourbière de Rogersville durant la période d’étude. À la tourbière Hardwood, un site de suivi de la sédimentation a été placé dans une zone tampon qui est entre le bassin de sédimentation et la rivière. Dans les deux tourbières, il a été constaté que les CSS n'étaient ni significativement corrélées avec la précipitation, ni avec les débits. Cependant, des séries chronologiques des CSS, débits et des précipitations ont montré que certains niveaux élevés des CSS ont été causés par des événements importants des débits et/ou précipitations. À la tourbière de Rogersville, il a été conclu que les mesures négatives de l’efficacité du bassin de sédimentation ont été associées à de fortes précipitations, mais seulement une très faible corrélation existait entre les précipitations et l'efficacité du bassin. Les activités de nettoyage du bassin de sédimentation ont eu une influence assez importante sur les niveaux des CSS, mais l’entretien des bassins n'a pas été suffisant pour assurer l’efficacité optimale du bassin de sédimentation. Dans les deux tourbières, la norme néo-brunswickoise des CSS de 25mg/L a été dépassée à chaque station et à chaque année. À la tourbière Hardwood, la station la plus affectée a été la station 2, située immédiatement en aval de la tourbière. La norme y a été dépassée 47% du temps en 2007 et 52% du temps en 2008. À Rogersville, les plus faibles taux de dépassements de la norme ont été trouvés à la station 1 avec un taux de dépassement de 64% du temps en 2008 et 62% du temps en 2009. À Rogersville, il n’a pas été possible de conclure que les épis ont contribué à améliorer l'efficacité du bassin de sédimentation. Une fois installés, les épis n'ont jamais été nettoyés. Une meilleure efficacité du bassin aurait pu éventuellement avoir été enregistrée si les épis avaient été correctement entretenus. Le faible volume du bassin de sédimentation et le fait qu’il ne corresponde pas aux lignes directrices du Nouveau-Brunswick ont également été des facteurs contribuant à la faible performance des épis. Le sable était le type de sédiment dominant déposé en aval des tourbières exploitée (Hardwood et Rogersville) durant les deux années, avec des quantités croissantes trouvées dans les sites les plus en aval. En outre, le pourcentage du contenu organique pour les sédiments inférieurs à 2 mm a été plus élevé que le pourcentage du contenu organique pour les sédiments supérieurs à 2 mm dans les deux tourbières pendant les deux années. À la tourbière Hardwood, le contenu organique était plus important dans les sédiments déposés dans le site 5 que sur les sites moins affectés de 1 à 4. Le contenu organique pour le site 5, pour les sédiments de tailles inférieures à 2 mm en 2007, a été significativement différent de celui des autres sites. À Rogersville, le contenu organique des sédiments inférieurs à 2 mm en 2008 a diminué progressivement de l’amont vers l’aval (sites 4 à 1), mais aucune différence significative n'a été trouvée entre les sites. En 2009, le site 2 a eu la plus haute valeur pour le contenu organique des sédiments inférieurs à 2 mm et le site 1 a le contenu organique le moins élevé.Peat harvesting is a growing industry in Canada. Peat harvesting is also carried out in several Nordic countries to meet the demand for horticultural grade peat moss. However, harvesting has some undesirable side effects such as drainage water containing peat sediment that flows into streams and rivers downstream of the harvested area. These sediments have been shown to negatively affect the natural environment. The aim of the project is to conduct a comparative study of the effectiveness of different methods of attenuation of sediment load produced by harvested peat bogs, with a special emphasis on the effectiveness of sedimentation ponds. Two different peat bogs, both operated by Premier Horticulture, in New Brunswick, Canada were studied for the current project; the Hardwood and Rogersville peat bogs. One objective of the study was to investigate if a relationship existed between discharge and suspended sediment concentration (SSC) and between rainfall and SSC on the East Branch Portage River and at the Rogersville peat bog. Other objectives were to determine if relationships existed between the efficiency of the sedimentation pond and harvesting activities or maintenance. In addition, one pond was modified during the study and baffles were added to verify if such structures would increase pond efficiency. Finally, data about the type and size of sediment deposited in the rivers downstream of the sedimentation ponds as well as the organic content of those deposits were gathered and analyzed. The Hardwood peatland has a sedimentation pond which meets the New Brunswick design guidelines. Three stations were monitored during the ice-free period of 2007 and 2008. Stations 1 and 2 were located respectively 2 km and 200 m downstream of the harvested peatland and Station 3 was located approximately 600 m upstream of all operational activities. Data were gathered at these sites from May 11th to November 9th in 2007 and from May 28th to October 1st in 2008. The Rogersville peatland, a well established and active harvested site with extensive drainage, had a sedimentation pond size that did not correspond to New Brunswick standards. The pond is located approximately 78 m downstream of the peat production area. Its length of 170 m was much higher than the recommended standard. This study, which took place from June 27th to November 25th in 2008 and from May 7th to December 9th in 2009, was one of the first to measure SSC at both the inflow and outflow of the sedimentation pond. SSC was also measured at Station 1 at a point approximately 1.16 km downstream of the sedimentation pond. At the Rogersville bog, baffles were installed in mid-October 2008 in the sedimentation pond to determine if they would improve the efficiency of the pond. These baffles remained in place for the remainder of 2008 and throughout the study period in 2009 and were never removed. Five sites with four sediment traps each were established at Hardwood in both years and four sites with three sediment traps each were set up at Rogersville in both years. At each peat bog, site 1 was located the furthest downstream of the sedimentation pond with each subsequent site moving further upstream. At Portage, site 5 was located in the buffer zone between the sedimentation pond and river, in an area close to harvesting activities. In both study areas, it was found that SSC levels were neither significantly correlated with precipitation nor discharge, although time series of SSC, discharge and rainfall suggested that some of the high SSC events were triggered by high discharge and/or precipitation. At Rogersville, it was found that negative pond efficiency measurements were triggered by heavy rainfall, but only a very weak correlation existed between rain and pond efficiency. Pond cleaning activities, however, had an important influence on SSC levels but cleaning on its own was not enough to ensure optimal sedimentation pond efficiency. Although pond cleaning did eventually decrease SSC levels at both the Rogersville and Hardwood settling ponds, pond maintenance can induce an increase in SSC for a period of up to one month. At both Rogersville and Hardwood, the New Brunswick SSC maximum threshold of 25mg/L was exceeded at each station in each year. At Hardwood, the most impacted station was Station 2, which exceeded the threshold 47% of the time in 2007 and 52% of the time in 2008. At Rogersville, lower exceedances were found at Station 1 with the threshold being exceeded 64% of the time in 2008 and 62% of the time in 2009. At Rogersville, no conclusive evidence was obtained indicating that the baffles helped to improve the efficiency of the pond. Once installed, the baffles were never cleaned. Better pond efficiency may possibly have been recorded, had the baffles been properly maintained. Small pond volume and the fact that the sedimentation pond did not conform to the New Brunswick guidelines were also likely factors in poor basin performance. Sand was the dominant sediment type deposited downstream of the harvested peat bogs (Hardwood and Rogersville) in both years with increasing quantities found further downstream. As well, the percentage organic matter &lt; 2 mm was higher than the percentage organic content > 2 mm at both bogs in both years. At Hardwood, more organic content was found in the deposited sediment at site 5 than at the less impacted sites 1 through 4. Organic content at site 5, for grain sizes &lt; 2 mm in 2007 was found to be significantly different then sites downstream of the harvested area. At Rogersville, in 2008, organic content &lt; 2mm was found in diminishing quantities from site 4 to 1 but no significant differences were noted between sites. In 2009, for organic content &lt; 2 mm, site 2 had the highest organic content and site 1 had the least. The two sites were found to be significantly different from each other

Poly(Glycerol Adipate-co-ω-Pentadecalactone) Spray-Dried Microparticles as Sustained Release Carriers for Pulmonary Delivery

Purpose The aim of this work was to optimize biodegradable polyester poly(glycerol adipate-co-ω-pentadecalactone), PGA-co-PDL, microparticles as sustained release (SR) carriers for pulmonary drug delivery. Methods Microparticles were produced by spray drying directly from double emulsion with and without dispersibility enhancers ( L -arginine and L -leucine) (0.5–1.5%w/w) using sodium fluorescein (SF) as a model hydrophilic drug. Results Spray-dried microparticles without dispersibility enhancers exhibited aggregated powders leading to low fine particle fraction (%FPF) (28.79 ± 3.24), fine particle dose (FPD) (14.42 ± 1.57 μg), with a mass median aerodynamic diameter (MMAD) 2.86 ± 0.24 μm. However, L -leucine was significantly superior in enhancing the aerosolization performance ( L- arginine:%FPF 27.61 ± 4.49–26.57 ± 1.85; FPD 12.40 ± 0.99–19.54 ± 0.16 μg and MMAD 2.18 ± 0.35–2.98 ± 0.25 μm, L -leucine:%FPF 36.90 ± 3.6–43.38 ± 5.6; FPD 18.66 ± 2.90–21.58 ± 2.46 μg and MMAD 2.55 ± 0.03–3.68 ± 0.12 μm). Incorporating L -leucine (1.5%w/w) reduced the burst release (24.04 ± 3.87%) of SF compared to unmodified formulations (41.87 ± 2.46%), with both undergoing a square root of time (Higuchi’s pattern) dependent release. Comparing the toxicity profiles of PGA-co-PDL with L -leucine (1.5%w/w) (5 mg/ml) and poly(lactide-co-glycolide), (5 mg/ml) spray-dried microparticles in human bronchial epithelial 16HBE14o- cell lines, resulted in cell viability of 85.57 ± 5.44 and 60.66 ± 6.75%, respectively, after 72 h treatment. Conclusion The above data suggest that PGA-co-PDL may be a useful polymer for preparing SR microparticle carriers, together with dispersibility enhancers, for pulmonary delivery