Laboratories

Lovere, Italy

Laboratories

Lovere, Italy
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Rauf A.,Gomal University | Rauf A.,King's College London | Baloch M.K.,Gomal University | Rauf S.,Gomal University | And 4 more authors.
Asian Journal of Chemistry | Year: 2013

Polyethylene oxide having different molecular mass (35, 6, 2 Kg/mol) were studied by densitometry and viscometry in the temperature range of 20-50 °C. Intrinsic viscosity (h) and interparticle interaction parameter (KH) were determined at various temperatures from viscometry. Micellar partial specific volume (nmic) and micellar density (rmic) were determined by density measurement at various temperatures. Energy of activation (Ea) was also calculated from intrinsic viscosity by using Arhenius equation. From the densitometric and viscometric results the amount of water in gram per gram associated with the aggregates of polymer (Wh) and shape factor of aggregate (micelle) were also determined. It was concluded that the intrinsic viscosity, micellar density and water associated with the polymer molecules were decreased as the temperature increased. While partial specific volume of polymer increased with the temperature.


Smith A.M.,South African National Institute for Communicable Diseases | Smith A.M.,University of Witwatersrand | Ismail H.,South African National Institute for Communicable Diseases | Ismail H.,University of Witwatersrand | And 3 more authors.
Journal of Infection in Developing Countries | Year: 2014

Introduction: Salmonella is well recognized as an aetiological agent of gastrointestinal and diarrhoeal disease. Salmonella enterica serotype Enteritidis (Salmonella Enteritidis) is one of the commonest serotypes associated with foodborne illness. In South Africa, we compared Salmonella Enteritidis strains isolated from humans with gastroenteritis and strains isolated from captive wild animals, between June 2011 and July 2012.Methodology: Bacteria were phenotypically characterized using standard microbiological techniques. Genotypic relatedness of isolates was investigated by pulsed-field gel electrophoresis (PFGE) analysis.Results: a diversity of 27 PFGE patterns amongst 196 human non-invasive isolates was shown; two PFGE patterns predominated and accounted for 74% of all human isolates. Human isolates showed a 12% prevalence rate for nalidixic acid resistance. Animal isolates from 5 different sources were investigated. With the exception of an isolate from a ground hornbill, all animal isolates (jaguar, crocodile, lion and poultry) showed PFGE pattern matches to a human isolate. Animal isolates showed susceptibility to all antimicrobial agents tested, with the exception of nalidixic acid resistance in isolates from the lion and poultry source.Conclusions: Our data showed similarities between Salmonella Enteritidis strains isolated from humans and captive wild animals, suggesting a probable common source for strains from humans and animals. © 2014 Smith et al.


Diener M.,ETH Zurich | Ghidini A.,Laboratories
Materials Performance and Characterization | Year: 2014

About 10 years ago, the European Standard EN13262 was introduced, and, for the first time in railways, the toughness characteristic of the rim has to be proofed for tread-braked solid wheels. For wheels of steel grade ER7 the average fracture toughness obtained from six test pieces shall be greater than or equal to 80 MPa m1/2 and no single value shall be less than 70MPa m1/2. The present paper focuses on the efforts in research and, of course, application of fracture mechanics to railway solid wheels. The obtained results demonstrate that the capability to measure fracture toughness of materials and a proper collection of the related metallurgical parameters help to develop the manufacturing process of wheels. The main challenge is to improve toughness in parallel with yield strength by maintaining a desired microstructure of the material. Some important correlations between structure and fracture toughness are specified and document how the toughness can be tuned. The properties on the production of solid wheels, monitored over a long period, have confirmed the ability to guarantee both high and uniform values of mechanical characteristics and toughness. This is an important result concerning product quality and safety of railway wheels. Fracture toughness and yield strength represent an appropriate quality index for any material and steel grade. A production index (PI), which is the product of yield strength and fracture toughness, is introduced to trace the quality of a material in production. Copyright © 2014 by ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959.


Muralidhara K.S.,Laboratories | Chhagan,CIRCOT | Sreenivasan S.,CIRCOT
Colourage | Year: 2012

Six textile fabrics of different fibre composition viz., polyester, polyester-cotton, cotton-flax, cotton, cotton-silk and jute were treated using flame retardant chemicals containing phosphorous, halogen and borate as active ingredient. LOI of treated cellulosic and its blended samples was increased by more than 100% after treatment with phosphorous ingredient FR chemical. The halogen ingredient based treatment exhibited 50-100% increase in LOI for the same samples. The speed of flame spread was reduced by more than 50% for the phosphorous ingredient treatment and reduction was less than 50% for other treatments. The borate based treatment exhibited increase in speed of flame spread in polyester cotton blended fabric. Phosphorous ingredient treatment yielded an additional endotherm at around 200°C in the thermogram. The degradation onset temperature point of all samples was lowered by more than 50°C for all the treatments. The observed mass loss was prolonged in the treated samples when compared to the control samples. The pattern of mass loss at different temperature intervals changed completely after the treatment. Flame retardants applied on the fabrics also decreased the activation energy of treated samples.


Haldimann M.,Laboratories | Bochud M.,University of Lausanne | Burnier M.,University of Lausanne | Paccaud F.,University of Lausanne | Dudler V.,Laboratories
Public Health Nutrition | Year: 2015

Objective To assess the iodine status of Swiss population groups and to evaluate the influence of iodized salt as a vector for iodine fortification. Design The relationship between 24 h urinary iodine and Na excretions was assessed in the general population after correcting for confounders. Single-day intakes were estimated assuming that 92 % of dietary iodine was excreted in 24 h urine. Usual intake distributions were derived for male and female population groups after adjustment for within-subject variability. The estimated average requirement (EAR) cut-point method was applied as guidance to assess the inadequacy of the iodine supply. Setting Public health strategies to reduce the dietary salt intake in the general population may affect its iodine supply. Subjects The study population (1481 volunteers, aged ≥15 years) was randomly selected from three different linguistic regions of Switzerland. Results The 24 h urine samples from 1420 participants were determined to be properly collected. Mean iodine intakes obtained for men (n 705) and women (n 715) were 179 (sd 68·1) g/d and 138 (sd 57·8) g/d, respectively. Urinary Na and Ca, and BMI were significantly and positively associated with higher iodine intake, as were men and non-smokers. Fifty-four per cent of the total iodine intake originated from iodized salt. The prevalence of inadequate iodine intake as estimated by the EAR cut-point method was 2 % for men and 14 % for women. Conclusions The estimated prevalence of inadequate iodine intake was within the optimal target range of 2-3 % for men, but not for women. Copyright © The Authors 2014.


PubMed | Laboratories
Type: Journal Article | Journal: IEEE transactions on pattern analysis and machine intelligence | Year: 2011

The relationship between parallel isometric array languages and sequential isometric array languages is examined. Their hierarchical structures are investigated and a hierarchy is established by introducing parallel context-free array languages (PCFAL), derivation bounded array languages (DBAL), linear array languages (LAL), and extended regular afray languages (ERAL). It is interesting to find that some fundamental aspects that hold in one-dimensional string languages do not hold in their two-dimensional counterparts. Some parsing techniques are also explored. It is shown that while parallel parsing grammars may be simpler to write and parallel processing usually takes less time than sequential ones, the nature of parallel parsing is very complicated. Finally, several future research topics concerned with parallel isometric array languages including their complexities, hierarchical structures, and application to pattern recognition are discussed.


PubMed | University of Lausanne and Laboratories
Type: Journal Article | Journal: Public health nutrition | Year: 2015

To assess the iodine status of Swiss population groups and to evaluate the influence of iodized salt as a vector for iodine fortification.The relationship between 24 h urinary iodine and Na excretions was assessed in the general population after correcting for confounders. Single-day intakes were estimated assuming that 92 % of dietary iodine was excreted in 24 h urine. Usual intake distributions were derived for male and female population groups after adjustment for within-subject variability. The estimated average requirement (EAR) cut-point method was applied as guidance to assess the inadequacy of the iodine supply.Public health strategies to reduce the dietary salt intake in the general population may affect its iodine supply.The study population (1481 volunteers, aged 15 years) was randomly selected from three different linguistic regions of Switzerland.The 24 h urine samples from 1420 participants were determined to be properly collected. Mean iodine intakes obtained for men (n 705) and women (n 715) were 179 (sd 68.1) g/d and 138 (sd 57.8) g/d, respectively. Urinary Na and Ca, and BMI were significantly and positively associated with higher iodine intake, as were men and non-smokers. Fifty-four per cent of the total iodine intake originated from iodized salt. The prevalence of inadequate iodine intake as estimated by the EAR cut-point method was 2 % for men and 14 % for women.The estimated prevalence of inadequate iodine intake was within the optimal target range of 2-3 % for men, but not for women.

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