Publications by authors named "Achache S"

This work uses the direct current magnetron sputtering (DCMS) of equi-atomic (AlTiZrHfTa) and Si targets in dynamic sweep mode to deposit nano-layered (AlTiZrHfTa)N/SiN refractory high-entropy coatings (RHECs). Transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) are used to investigate the effect of Si addition on the oxidation behavior of the nano-layered coatings. The Si-free nitride coating exhibits FCC structure and columnar morphology, while the Si-doped nitride coatings present a FCC (AlTiZrHfTa)N/amorphous-SiN nano-layered architecture.

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Background: Mutations in the Plasmodium falciparum dhfr gene confer resistance to pyrimethamine, which is widely used for malaria chemoprevention in Africa. We aimed to evaluate the frequency and evolution of dhfr mutations in Plasmodium ovale spp in Africa and their functional consequences, which are incompletely characterised.

Methods: We analysed dhfr mutations and their frequencies in P ovale spp isolates collected between Feb 1, 2004, and Aug 31, 2023, from the French National Malaria Reference Centre collection and from field studies in Benin, Gabon, and Kenya.

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Article Synopsis
  • The article discusses the effects of nitrogen content on the structural and mechanical properties of AlTiZrTaHf high entropy films, which were created using a technique called reactive magnetron sputtering.
  • X-ray photoelectron spectroscopy (XPS) measurements were performed to analyze the composition of the films, revealing the presence of nitrides and oxides at the surface.
  • The study shows that as the nitrogen flow rate increases, the amount of nitrogen in the films rises while the metallic fractions decrease, highlighting the nitridation behavior of the different elements in the films.
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This article presents the evidence for the significant effect of copper accelerating the bacterial inactivation on Ti-Nb-Ta-Zr (TNTZ) sputtered films on glass up to a Cu content of 8.3 at.%.

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Super-elastic Titanium based thin films Ti-23Nb-0.7Ta-2Zr-(O) (TNTZ-O) and Ti-24Nb-(N) (TN-N) (at.%) were deposited by direct current magnetron sputtering (DCMS) in different reactive atmospheres.

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The authors review the lesions which may be seen during orthopedic treatment involving multi-attachment dentures which they use for their clinical cases. They emphasise that these iatrogenic lesions can be avoided by the use of moderate forces appropriately applied and the functional conception of orthopedic treatment.

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The author point out that periodontitis is a disease of multiple aetiology and indicate two types of pitfall: traps in conceiving the plan of treatment and traps in carrying out treatment. The treatment plan may be incomplete. The authors show that the deepest types of vertical alveolysis are always related to occlusal or functional imbalance and that treatment based only upon hygiene and periodontal surgery represents a pitfall.

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The authors describe the various etiological types of periodontopathies and discuss those due to inflammatory conditions in greater detail. The original studies that enabled the role of the bacterial plaque to be demonstrated are reviewed, and new data presented which attributes a specific pathogenic action to certain bacterial strains in this particular form of the disease, without suggesting that they are the only etiological factor involved. The importance of occlusal injury in periodontal disease is then evaluated, results of clinical studies tending to confirm the role of traumatic factors in the progression of alveolysis.

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