Interest of the therapeutic education in patients with type 2 diabetes observing the fast of Ramadan

AbstractThe fast of Ramadan is a dilemma for diabetic patients due to the complexity of the management of diabetes during this holy month and the multiple risks they face (hypoglycemia, etc.).ObjectivesEvaluate the impact of a structured protocol of therapeutic education in a sample of type 2 diabetes, who were authorized by their doctors to fast, on metabolic and anthropometric profiles.MethodsThis prospective study was conducted among 54 type 2 diabetic patients (28 men and 26 women) aged 36–65years, recruited from National Nutrition Institute. Patients were divided into two groups: the first group (n=26) received an education session one to two weeks before the month of Ramadan; the second group (n=28) did not have appropriate therapeutic education except therapeutic adjustments. All our diabetic patients benefited from anthropometric measurements, determination of body composition and metabolic assessment (HbA1c, cholesterol, triglycerides, etc.) before and after the month of Ramadan.ResultsThe fast was completed without complications in 25 diabetic patients educated group and 22 control patients.We found that weight loss was greater among educated diabetic patients (−1.05kg) than in controls (−0.58kg), but without statistical significance. Body composition has not undergone significant changes in both diabetic groups.Therapeutic education has led to a decline of 0.27% in HbA1c in the educated group while glycemic control in diabetic patients uneducated remained stable. Furthermore, we observed a better lipid profile in diabetic patients educated than those who did not have education.ConclusionOur results justify the interest of patient education centered on the month of Ramadan in all type 2 diabetic patients observing the fast of the holy month. This education should be continued during Ramadan in order to fulfill this religious rite safely

ETUDE PAR SPECTROSCOPIE INFRAROUGE DE L'OZONE ET DU DIOXYDE DE SOUFRE ADSORBES SUR LA SURFACE DE LA GLACE OU PIEGES DANS SON VOLUME ENTRE 10 ET 170 K. EFFETS D'IRRADIATION A 266 NM SUR LE MELANGE O 3 + SO 2 PIEGE EN MATRICE D'ARGON OU DANS LA GLACE

PARIS-BIUSJ-Physique recherche (751052113) / SudocCentre Technique Livre Ens. Sup. (774682301) / SudocSudocFranceF

Thermal desorption of formamide and methylamine from graphite and amorphous water ice surfaces

International audienceContext. Formamide (NH 2 CHO) and methylamine (CH 3 NH 2) are known to be the most abundant amine-containing molecules in many astrophysical environments. The presence of these molecules in the gas phase may result from thermal desorption of interstellar ices.Aims. The aim of this work is to determine the values of the desorption energies of formamide and methylamine from analogues of interstellar dust grain surfaces and to understand their interaction with water ice.Methods. Temperature programmed desorption (TPD) experiments of formamide and methylamine ices were performed in the sub-monolayer and monolayer regimes on graphite (HOPG) and non-porous amorphous solid water (np-ASW) ice surfaces at temperatures 40-240 K. The desorption energy distributions of these two molecules were calculated from TPD measurements using a set of independent Polanyi-Wigner equations.Results. The maximum of the desorption of formamide from both graphite and ASW ice surfaces occurs at 176 K after the desorption of H 2 O molecules, whereas the desorption profile of methylamine depends strongly on the substrate. Solid methylamine starts to desorb below 100 K from the graphite surface. Its desorption from the water ice surface occurs after 120 K and stops during the water ice sublimation around 150 K. It continues to desorb from the graphite surface at temperatures higher than160 K.Conclusions. More than 95% of solid NH 2 CHO diffuses through the np-ASW ice surface towards the graphitic substrate and is released into the gas phase with a desorption energy distribution E des = 7460-9380 K, which is measured with the best-fit pre-exponential factor A = 10 18 s −1. However, the desorption energy distribution of methylamine from the np-ASW ice surface (E des = 3850-8420 K) is measured with the best-fit pre-exponential factor A = 10 12 s −1. A fraction of solid methylamine monolayer of roughly 0.15 diffuses through the water ice surface towards the HOPG substrate. This small amount of methylamine desorbs later with higher binding energies (5050-8420 K) that exceed that of the crystalline water ice (E des = 4930 K), which is calculated with the same pre-exponential factor A = 10 12 s −1. The best wetting ability of methylamine compared to H 2 O molecules makes CH 3 NH 2 molecules a refractory species for low coverage. Other binding energies of astrophysical relevant molecules are gathered and compared, but we could not link the chemical functional groups (amino, methyl, hydroxyl, and carbonyl) with the binding energy properties. Implications of these high binding energies are discussed

Reactivity of formic acid (HCOOH) with H atoms on cold surfaces of interstellar interest

International audienceContext. Formic acid (HCOOH) is the simplest organic carboxylic acid in chemical synthesis and the significant species in interstellar chemistry. HCOOH has been abundantly detected in interstellar ices, dense molecular clouds and star-forming regions.Aims. Laboratory hydrogenation experiments of HCOOH molecules with H atoms were performed with two cryogenic ultra-high vacuum devices on amorphous solid water ices, and highly oriented pyrolytic graphite surfaces. The aim of this work is to study the reactivity of HCOOH molecules with H atoms at low surface temperature 10 K, low surface coverage of one monolayer to three layers, and low H-atom flux of about 3.0 × 1012 molecule cm−2 s−1.Methods. HCOOH and H beams were deposited on cold surfaces held at 10 K, and the condensed films were analyzed by in-situ Reflection Absorption InfraRed Spectroscopy and temperature programmed desorption mass spectrometry technique by heating the sample from 10 to 200 K.Results. Using the temperature programmed during exposure desorption technique, we highlight the possible dimerization of HCOOH molecules at low surface temperatures between 10 and 100 K. In our HCOOH+H experiments, we evaluated a consumption of 20–30% of formic acid by comparing the TPD curves at m/z 46 of pure and H-exposed HCOOH ice.Conclusions. The hydrogenation HCOOH+H reaction is efficient at low surface temperatures. The main products identified experimentally are carbon dioxide (CO2) and water (H2O) molecules. CO bearing species CH3OH, and H2CO are also detected mainly on graphite surfaces. A chemical surface reaction route for the HCOOH+H system is proposed to explain the product formation

Deuteration of ammonia with D atoms on oxidized partly ASW covered graphite surface

Deuteration of moleculesThe deuteration of ammonia by D atoms has been investigated experimentally in the sub-monolayer regime on realistic analogues of interstellar dust grain surfaces. About 0.8 monolayer of solid NH 3 was deposited on top of an oxidized graphite surface held at 10 K, partly covered with ASW ice. Ammonia ice is subsequently exposed to D atoms for different exposure times using a differentially pumped beam-line. The deuteration experiments of ammonia were carried out by mass spectroscopy and temperature programmed desorption (TPD) technique. The experimental results showed the formation of three isotopologue ammonia species by direct exothermic H-D substitution surface reactions: NH 3 + D → NH 2 D + H, NH 2 D + D → NHD 2 + H, and NHD 2 + D → ND 3 + H. The formation of the deuterated isotopologues NH 2 D, NHD 2 , and ND 3 at low surface temperature (10 K) is likely to occur through quantum tunneling process on the oxidized graphite surface. A kinetic model taking into account the diffusion of D atoms on the surface is developed to estimate the width and the hight of the activation energy barriers for the successive deuteration reactions of ammonia species by D atoms. Identical control experiments were performed using CH 3 OH and D atoms. The deuteration process of solid methanol is ruled by H abstraction and D addition mechanism, and is almost five orders of magnitude faster than ammonia deuteration process

Deuteration of ammonia with D atoms on oxidized partly ASW covered graphite surface

Deuteration and isotopic exchange of moleculesThe deuteration of ammonia by D atoms has been investigated experimentally in the sub-monolayer regime on realistic analogues of interstellar dust grain surfaces. About 0.8 monolayer of solid NH 3 was deposited on top of an oxidized graphite surface held at 10 K, partly covered with ASW ice. Ammonia ice is subsequently exposed to D atoms for different exposure times using a differentially pumped beam-line. The deuteration experiments of ammonia were carried out by mass spectroscopy and temperature programmed desorption (TPD) technique. The experimental results showed the formation of three isotopologue ammonia species by direct exothermic H-D substitution surface reactions: NH 3 + D → NH 2 D + H, NH 2 D + D → NHD 2 + H, and NHD 2 + D → ND 3 + H. The formation of the deuterated isotopologues NH 2 D, NHD 2 , and ND 3 at low surface temperature (10 K) is likely to occur through quantum tunneling process on the oxidized graphite surface. A kinetic model taking into account the diffusion of D atoms on the surface is developed to estimate the width and the hight of the activation energy barriers for the successive deuteration reactions of ammonia species by D atoms. Identical control experiments were performed using CH 3 OH and D atoms. The deuteration process of solid methanol is ruled by H abstraction and D addition mechanism, and is almost five orders of magnitude faster than ammonia deuteration process

Competing Mechanisms of Molecular Hydrogen Formation in Conditions Relevant to the Interstellar Medium

International audienceThe most efficient mechanism of the formation of molecular hydrogen in the current universe is by association of hydrogen atoms on the surface of interstellar dust grains. The details of the processes of its formation and release from the grain are of great importance in the physical and chemical evolution of the space environments where it takes place. The main puzzle is still the fate of the 4.5 eV released in H2 formation and whether it goes into internal energy (rovibrational excitation), translational kinetic energy, or heating of the grain. The modality of the release of this energy affects the dynamics of the ISM and its evolution toward star formation. We present results of the detection of the rovibrational states of the just-formed H2 as it leaves the surface of a silicate. We find that rovibrationally excited molecules are ejected into the gas phase immediately after formation over a much wider range of grain temperatures than anticipated. Our results can be explained by the presence of two mechanisms of molecule formation that operate in partially overlapping ranges of grain temperature. A preliminary analysis of the relative importance of these two mechanisms is given. These unexpected findings, which will be complemented with experiments on the influence of factors such as silicate morphology, should be of great interest to the astrophysics and astrochemistry communities

A context modeling approach and a tool for reusing learning scenarios

With the evolution of teaching modalities and the high integration of the technology in the learning processes, teachers proceed to the design of learning situations in order to plan and formalize their educational experiences and share them with students and other teachers. Various academic and community initiatives of experience sharing and resulting learning scenarios repositories have emerged. This leads us to discuss the learning scenarios reuse issue, which becomes an essential practice for capitalization. Since the learning contexts are continuously changing, it could represent an obstacle to the reuse and the appropriation of learning scenarios. It therefore becomes important to consider the context dimension to assist teachers in the scenarios reuse situations. This paper deals firstly with the proposition of an approach to model learning scenarios context. Based on this modeling approach, this paper is interested in the retrieval of learning scenarios that most fit a target learning situation context by presenting a context similarity algorithm matching contextual models. The retrieval is based on contextual indexes related to scenarios. The indexing process is consolidated by the observation of the prior user-experiences of learning scenarios. An authoring tool is then presented integrating the context modeling approach and the detailed algorithm. Simulations of the implemented tool and related results are detailed within this paper

Gas temperature dependent sticking of hydrogen on cold amorphous water ice surfaces of interstellar interest

International audienceUsing the King and Wells method, we present experimental data on the dependence of the sticking of molecular hydrogen and deuterium on the beam temperature onto nonporous amorphous solid water ice surfaces of interstellar interest. A statistical model that explains the isotopic effect and the beam temperature behavior of our data is proposed. This model gives an understanding of the discrepancy between all known experimental results on the sticking of molecular hydrogen. Moreover, it is able to fit the theoretical results of Buch et al. [Astrophys. J. 379, 647 (1991)] on atomic hydrogen and deuterium. For astrophysical applications, an analytical formula for the sticking coefficients of H, D, H2, D2, and HD in the case of a gas phase at thermal equilibrium is also provided at the end of the article

Formation of water on silicate surfaces under interstellar conditions

International audienceWe explore experimentally the formation of water molecules from O2 and D atoms on bare grains composed of amorphous silicates analogous to those in diffuse interstellar clouds. We provide the fractions of D2O and D2O2 molecules formed on the silicate surface held at 10 K from the O2 D pathway using RAIRS and TPD techniques. For comparison, we also study the formation of water molecules on surfaces covered with amorphous water ice representing the dense clouds