Electrical properties and defect chemistry of anatase (TiO2)

The electrical properties of pure Anatase are investigated by impedance spectroscopy as function of temperature and oxygen partial pressure. The experimental results are fully interpreted by point defect chemistry. A transition from predominant Schottky to Frenkel cation disorder is observed when the temperature increases and/or the oxygen partial pressure decreases. The reduction enthalpies are near those obtained for Rutile in previous studies

Hot pressing of nanocrystalline TiO2 (anatase) ceramics with controlled microstructure

The preparation conditions of nanocrystalline phase-pure TiO2 anatase ceramics by hot pressing are described. Density, surface area, pore size distribution and grain size are determined by various techniques, including gas adsorption, mercury porosimetry, transmission electron microscopy (TEM) and X-ray diffraction (XRD). The evolution of the structural parameters is followed as function of temperature and pressure programme. It is shown that the porosity, grain and pore size of the ceramics can be controlled by a suitable choice of experimental conditions. Ceramics with densities higher than 90% of the theoretical limit with a mean grain size of 30 nm can be obtained at temperatures as low as 490 ◦C under 0.45 GPa for 2 h. The experimental results are discussed in view of the sintering theory

Hot compaction of nanocrystalline TiO2 (anatase) ceramics. Mechanisms of densification: Grain size and doping effects

The hot compaction of nanocrystalline TiO2 anatase powders is investigated using dilatometry. The constant rate of heating (CRH) method is applied to determine effective activation energies of the processes involved during sintering. Grain size and doping effects are studied, using dopant cations of different radius and charge: Zn2+, Al3+, Si4+, Nb5+. The results are interpreted by a mechanism including superplastic deformation and boundary diffusion. The former is predominant for small particles and low temperature, whereas the latter is more important for larger particles and higher temperature. Dopant effects on densification kinetics are discussed in view of defect chemistry

DYSLIPIDEMIA IN PATIENTS WITH DIABETES: ETIOLOGY AND MANAGEMENT

Diabetic dyslipidemia is a cluster of lipoprotein abnormalities characterized by increase in triglyceride level, decrease in high-density lipoprotein-cholesterol levels and increase in small dense low-density lipoprotein (LDL) particles.  It is most common to have dyslipidemia in type 2 diabetic patients and it affects 70% of the patients. Diabetis is a major risk factor for atherosclerotic cardiovascular disease (ASCVD) which is one most common reasons  of death in many countries. In this review we have discussed several pharmacological and non paharmacological treatment modalities including several trials which had positive effects on cardiovascular events in patients who has diabetes. ASCVD is is reduced in patients by lowering the LDL-C levels by 30 to 45 % usinf statin therapy. Other therapies like Ezetimibe, pcsk9, has shown posititve effects on loweing LDL-C levels and ASCVD event reduction

Jules Verne 2.0, renewal of a large wind tunnel facility

International audienceThe paper aims at showing the evolution of methods to design a large wind tunnel. The current Jules Verne facility was designed with a scale model of the wind tunnel which enabled hot wire local wind speed measurements. The new facility is designed according a numerical modelling approach which parameters were validated by PIV measurements in the reduced scale physical model

Diversidad críptica en gasterópodos mediterráneos del género Aplus (Neogastropoda: Buccinidae)

Northeastern Atlantic and Mediterranean gastropods previously ascribed to the buccinid genus Pollia Gray, 1837 are more correctly classified in the genus Aplus de Gregorio, 1885. Using an integrative taxonomy approach combining molecular, morphological and geographic data, we revisit the limits of the extant species in the area, and propose a molecular phylogenetic hypothesis based on 66 specimens from various localities in the Mediterranean Sea, including type localities of some nominal taxa. We used a preliminary morphological inspection, followed by a DNA-barcoding approach to propose species hypotheses, subsequently consolidated using additional data (phylogenetic, geographic and refined morphological data). Seven species hypotheses were eventually retained within our molecularly assayed samples, versus three classical morphologically recognized species. Among these, three correspond to Aplus dorbignyi (Payreaudeau, 1826) with its hitherto unrecognized geographical cognates A. gaillardoti (Puton, 1856) (eastern Mediterranean) and Aplus nodulosus (Bivona Ant., 1832) (Sicily); two closely related, yet considerably divergent, lineages are treated as a single species under Aplus scaber (Locard, 1892); the classically admitted Aplus scacchianus (Philippi, 1844) is confirmed by molecular evidence; Mediterranean populations attributable to Aplus assimilis (Reeve, 1846) may represent either cryptic native populations or an ongoing invasion of the Mediterranean by what was hitherto considered to be a West African species; finally, specimens from the Strait of Gibraltar may represent an undescribed species, but we conservatively refrain from formally introducing it pending the analysis of more material, and it is compared with the similar Aplus campisii (Ardovini, 2014), recently described from Sicily and not assayed molecularly, and Aplus scaber.Los gasterópodos mediterráneos y del Atlántico nordeste previamente asignados al género Pollia Gray, 1837 deben ser más correctamente incluidos en el género Aplus de Gregorio, 1885. Se revisan aquí los límites de las especies recientes de este género en el área estudiada por medio de un enfoque de taxonomía integrativa. En base a ello se propone una hipótesis filogenética basada en 66 ejemplares procedentes de varias localidades del Mediterráneo, incluyendo las localidades tipo de algunos taxones nominales. Primero se realizó una diferenciación morfológica, seguida de la aplicación del marcador molecular COI para proponer las especies a modo de hipótesis, que finalmente fueron validadas con datos adicionales (filogenéticos, geográficos y detalles morfológicos). Como resultado se reconocieron siete especies válidas entre los ejemplares analizados molecularmente, en contraste con las tres especies previamente reconocidas morfológicamente. Tres de ellas corresponden a Aplus dorbignyi (Payreaudeau, 1826) y a sus afines geográficos no reconocidas hasta ahora A. gaillardoti (Puton, 1856) [del Mediterráneo oriental] y Aplus nodulosus (Bivona Ant., 1832) [de Sicilia]; dos linajes estrechamente relacionados, aunque divergentes, son considerados como una misma especie con el nombre de Aplus scaber (Locard, 1892); la especie tradicionalmente admitida Aplus scacchianus (Philippi, 1844) se confirma en base a evidencias moleculares; las poblaciones mediterráneas atribuibles a Aplusas similis (Reeve, 1846) pueden ser crípticas nativas o corresponder a una invasión en curso por parte de esta especie del noroeste africano; finalmente los ejemplares del Estrecho de Gibraltar pueden representar una especie no descrita, pero se ha preferido optar por una posición conservadora y no introducir un nuevo nombre a la espera del estudio de material adicional y compararla con Aplus campisii (Ardovini, 2014), especie descrita recientemente de Sicilia y pendiente de su análisis molecular, y con Aplus scaber