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Abstract  

The chemical behaviour of the95Nb atoms formed by the beta decay of the95Zr-Alizarin S and95Zr-TTA (2-thenoyltrifluoracetone) complexes were investigated. The retention values of95Nb which not complexed with organic reagents at working pH were determined. The values observed were 100% and 80%, respectively. The results are discussed and interpreted to explain the different behaviour on the basis of internal energy values and solvent effects.

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Abstract  

Proline and hydroxyproline are two amino acids which due to their analogous chemical structures give similar reactions and often appear together. In view of the high percentage of proline in wheat gluten we have investigated the presence of hydroxyproline in wheat flour. We have developed a method to separate the two amino acids after separation from other interfering amino acids which are present in flour. The method of separation utilizes an ion-exchange column/Dowex 50 X-8, 100–200 resin/. The separated amino acids are determined either by spectrophotometry or isotope dilution /14C/ The latter method is more rapid and more sensitive than the spectrophotometric method.

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Alternative biofuels

PVTx measurements for DME + propane

Journal of Thermal Analysis and Calorimetry
Authors:
A. Arteconi
,
G. Di Nicola
,
M. Moglie
,
G. Santori
, and
R. Stryjek

Abstract  

This study presents the experimental results for the dimethyl ether (DME) + propane system obtained using the Burnett method. The apparatus was calibrated using helium. PVTx measurements were taken for four isotherms (344, 354, 364, and 375 K), performing 16 Burnett expansions in pressures ranging from about 3,000 to 70 kPa. The second and third virial coefficients were derived from experimental results. The experimental uncertainty in the second and third virial coefficients was estimated to be within ±5 cm3/mol and ±1,000 cm6/mol2, respectively.

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Abstract  

Dimethyl ether is an important chemical material and it has many engineering applications. It is a clean and economical alternative fuel and an ozone-friendly refrigerant. In this work, its PVT properties have been object of study. In particular, the experimental work was performed both in the two-phase region and in the superheated vapor region phase by means of the isochoric method. The isochoric measurements were carried out at temperatures from 219 K to 363 K and at pressures from 22 kPa up to 1,740 kPa. A total of 159 points, both in the two phase (71 points) and in the superheated vapor region (88 points) were obtained. The present experimental PVT data contribute to the deeper knowledge of the behaviour of the fluid both in the superheated vapour and in the saturation pressure region and to the development of a new equation of state.

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Journal of Behavioral Addictions
Authors:
Nicolas A. Bonfils
,
Marie Grall-Bronnec
,
Julie Caillon
,
Frédéric Limosin
,
Amine Benyamina
,
Henri-Jean Aubin
, and
Amandine Luquiens

Background and aims

Problem gambling is characterized by high stigma and self-stigma, making relevant measurement of the burden of the disorder complex. The aim of our qualitative study was to describe health-related quality of life (HRQOL) impacted by problem gambling from the patients’ perspective.

Methods

We conducted 6 focus groups with 25 current or lifetime at-risk problem gamblers to identify key domains of quality of life impacted by problem gambling. A content analysis from the focus groups data was conducted using Alceste© software, using descendant hierarchical classification analysis, to obtain stable classes and the significant presences of reduced forms. The class of interest, detailing the core of impacted quality of life, was described using a cluster analysis.

Results

Thematic content analysis identified three stable classes. Class 1 contained the interviewers’ speech. Class 3 was composed of the vocabulary related to gambling practice, games and gambling venues (casino, horse betting, etc.). Class 2 described the core of impact of gambling on quality of life and corresponded to 43% of the analyzed elementary context units. This analysis revealed seven key domains of impact of problem gambling: loneliness, financial pressure, relationships deterioration, feeling of incomprehension, preoccupation with gambling, negative emotions, and avoidance of helping relationships.

Conclusions

We identified, beyond objective damage, the subjective distress felt by problem gamblers over the course of the disorder and in the helping process, marked in particular by stigma and self-stigma. Four impacted HRQOL areas were new and gambling-specific: loneliness, feeling of incomprehension, avoidance of helping relationships, and preoccupation with gambling. These results support the relevance of developing, in a next step, a specific HRQOL scale in the context of gambling.

Open access
Journal of Behavioral Addictions
Authors:
Philip Nielsen
,
Maxwell Christensen
,
Craig Henderson
,
Howard A Liddle
,
Marina Croquette-Krokar
,
Nicolas Favez
, and
Henk Rigter

Abstract

Background and aims

Social variables including parental and family factors may serve as risk factors for Internet Gaming Disorder (IGD) in adolescents. An IGD treatment programme should address these factors. We assessed two family therapies – multidimensional family therapy (MDFT) and family therapy as usual (FTAU) – on their impact on the prevalence of IGD and IGD symptoms.

Methods

Eligible for this randomised controlled trial comparing MDFT (N = 12) with FTAU (N = 30) were adolescents of 12–19 years old meeting at least 5 of the 9 DSM-5 IGD criteria and with at least one parent willing to participate in the study. The youths were recruited from the Centre Phénix-Mail, which offers outpatient adolescent addiction care in Geneva. Assessments occurred at baseline and 6 and 12 months.

Results

Both family therapies decreased the prevalence of IGD across the one-year period. Both therapies also lowered the number of IGD criteria met, with MDFT outperforming FTAU. There was no effect on the amount of time spent on gaming. At baseline, parents judged their child’s gaming problems to be important whereas the adolescents thought these problems were minimal. This discrepancy in judgment diminished across the study period as parents became milder in rating problem severity. MDFT better retained families in treatment than FTAU.

Discussion and Conclusions

Family therapy, especially MDFT, was effective in treating adolescent IGD. Improvements in family relationships may contribute to the treatment success. Our findings are promising but need to be replicated in larger study.

Trial registration number

ISRCTN 11142726.

Open access
Journal of Flow Chemistry
Authors:
Christophe A. Serra
,
Ikram U. Khan
,
ZhenQi Chang
,
Michel Bouquey
,
René Muller
,
Isabelle Kraus
,
Marc Schmutz
,
Thierry Vandamme
,
Nicolas Anton
,
Christian Ohm
,
Rudolf Zentel
,
Andrea Knauer
, and
Michael Köhler

Abstract

Capillary-based flow-focusing and co-flow microsystems were developed to produce sphere-like polymer microparticles of adjustable sizes in the range of 50 to 600 μm with a narrow size distribution (CV < 5%) and different morphologies (core-shell, janus, and capsules). Rod-like particles whose length was conveniently adjusted between 400 μm and few millimeters were also produced using the same microsystems. Influence of operating conditions (flow rate of the different fluid, microsystem characteristic dimensions, and design) as well as material parameters (viscosity of the different fluids and surface tension) was investigated. Empirical relationships were thus derived from experimental data to predict the microparticle's overall size, shell thickness, or rods length. Besides morphology, microparticles with various compositions were synthesized and their potential applications highlighted: drug-loaded microparticles for new drug delivery strategies, composed inorganic-organic multiscale microparticles for sensorics, and liquid crystalline elastomer microparticles showing an anisotropic reversible shape change upon temperature for thermal actuators or artificial muscles.

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European Journal of Microbiology and Immunology
Authors:
Ali Konaté
,
René Dembélé
,
Nathalie K. Guessennd
,
Fernique Konan Kouadio
,
Innocent Kouamé Kouadio
,
Mohamed Baguy Ouattara
,
Wendpoulomdé A. D. Kaboré
,
Assèta Kagambèga
,
Haoua Cissé
,
Hadiza Bawa Ibrahim
,
Touwendsida Serge Bagré
,
Alfred S. Traoré
, and
Nicolas Barro

The emergence and persistence of multidrug-resistant (MDR) diarrheagenic Escherichia coli (DEC) causing acute diarrhea is a major public health challenge in developing countries. The aim of this study was to evaluate the resistance phenotypes of DEC isolated from stool samples collected from children less than 5 years of age with acute diarrhea living in Ouagadougou/Burkina Faso. From August 2013 to October 2015, this study was carried out on 31 DEC strains of our study conducted in “Centre Médical avec Antenne Chirurgicale (CMA)” Paul VI and CMA of Schiphra. DEC were isolated and identified by standard microbiological methods and polymerase chain reaction (PCR) method was used to further characterize them. Antimicrobial susceptibility testing was done based on the disk diffusion method. DEC isolates were high resistant to tetracycline (83.9%), amoxicillin (77.4%), amoxicillin clavulanic acid (77.4%), piperacillin (64.5%), and colistin sulfate (61.3%). The most resistant phenotype represented was the extended spectrum β-lactamase (ESBL) phenotype (67.7%). Aminoglycosides were 100% active on enteroinvasive E. coli (EIEC) and enterohemorrhagic E. coli (EHEC). All the DEC isolates exhibited absolute (100%) sensitivity to ciprofloxacin. Monitoring and studying the resistance profile of DEC to antibiotics are necessary to guide probabilistic antibiotic therapy, especially in pediatric patients.

Open access
European Journal of Microbiology and Immunology
Authors:
Ali Konaté
,
René Dembélé
,
Assèta Kagambèga
,
Issiaka Soulama
,
Wendpoulomdé A. D. Kaboré
,
Emmanuel Sampo
,
Haoua Cissé
,
Antoine Sanou
,
Samuel Serme
,
Soumanaba Zongo
,
Cheikna Zongo
,
Alio Mahamadou Fody
,
Nathalie K. Guessennd
,
Alfred S. Traoré
,
Amy Gassama-Sow
, and
Nicolas Barro

Diarrheagenic Escherichia coli (DEC) is important bacteria of children’s endemic and epidemic diarrhea worldwide. The aim of this study was to determine the prevalence of DEC isolated from stool samples collected from children with acute diarrhea living in Ouagadougou, Burkina Faso. From August 2013 to October 2015, stool samples were collected from 315 children under 5 years of age suffering from diarrhea in the “Centre Médical avec Antenne Chirurgicale (CMA)” Paul VI and the CMA of Schiphra. E. coli were isolated and identified by standard microbiological methods, and the 16-plex PCR method was used to further characterize them. Four hundred and nineteen (419) E. coli strains were characterized, of which 31 (7.4%) DEC pathotypes were identified and classified in five E. coli pathotypes: 15 enteroaggregative E. coli (EAEC) (48.4%), 8 enteropathogenic E. coli (EPEC) (25.8%) with 4 typical EPEC and 4 atypical EPEC, 4 enteroinvasive E. coli (EIEC) (12.9%), 3 enterohemorrhagic E. coli (EHEC) 9.67%, and 1 enterotoxigenic E. coli (ETEC) 3.2%. The use of multiplex PCR as a routine in clinical laboratory for the detection of DEC would be a useful mean for a rapid management of an acute diarrhea in children.

Open access