484 research outputs found

    Synthesis and characterisation of nanocrystalline ZrN PVD coatings on AISI 430 stainless steel

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    The nanocrystalline films of zirconium nitride have been synthesized using ion-plasma vacuum-arc deposition technique in combination with high-frequency discharge (RF) on AISI 430 stainless steel at 150oC. Structure examinations X-ray fluorescent analysis (XRF), X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) with microanalysis (EDS), and transmission electron microscopy (TEM), nanoidentation method – were performed to study phase and chemical composition, surface morphology, microstructure and nanohardness of coatings. The developed technology provided low-temperature coatings synthesis, minimized discharge breakdown decreasing formation of macroparticles (MPs) and allowed to deposit ZrN coatings with hardness variation 26.6…31.5 GPa. It was revealed that ZrN single-phase coatings of cubic modification with finecrystalline grains of 20 nm in size were formed

    Anti-corrosion ceramic coatings on the surface of Nd-Fe-B repelling magnets

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    The results of vacuum-arc deposition of thin ZrO₂coatings to protect the surface of Nd-Fe-B permanent magnets used as repelling devices in orthodontics are presented. The structure, phase composition and mechanical properties of zirconium dioxide films have been investigated by means of SEM, XRD, EDX, XRF and nanoindentation method. It was revealed the formation of polycrystalline ZrO₂ films of monoclinic modification with average grain size 25 nm. The influence of the ZrO₂ coating in terms of its barrier properties for corrosion in quasi-physiological 0.9 NaCl solution has been studied. Electrochemical measurements indicated good barrier properties of the coating on specimens in the physiological solution environment

    Transreolar breast augmentation - surgery’s risks and complications

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    Catedra Ortopedie – Traumatologie, USMF “N. Testemițanu”, Al XI-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” din Republica Moldova și cea de-a XXXIII-a Reuniune a Chirurgilor din Moldova „Iacomi-Răzeșu” 27-30 septembrie 2011Intervenția de augmentare mamară este o intervenție chirurgicală efectuată pentru a mări sânii din diverse motive: pentu a obține un mai frumos contur al corpului femeii, care din motive personale simte că mărimea sânilor ei este prea mică; pentru a corecta o pierdere în volum a sânilor după o sarcină; pentru a obține un echilibru între mărimile sânilor atunci când există diferențe între cei doi sâni; ca metodă reconstructivă a sânilor din diferite motive; înlocuirea implanturilor mamare din considerente medicale sau cosmetice. Mărirea sânilor este realizată prin inserarea de implanturi mamare fie în spatele țesutului glandular ori sub muşchii pectorali. Inciziile sunt efectuate astfel încât să fie cât mai puțin vizibile, de obicei în jurul marginii inferioare a areolei. Metoda de inserție şi poziționare a implanturilor mamare va depinde de preferințele pacientei, de anatomia şi de recomandările chirurgului plastician. Fiecare procedură chirurgicală implică un anumit grad de risc: sîngerarea, infecția, contracții capsulare, modificarea poziției mamelonului şi a sensibilității pielii, cicatricile, extrudarea implantului, ridarea pielii sau apariția neuniformităților pe suprafața pielii, calcifierea, migrarea implantului, contaminarea suprafeței implanturilor, deformarea peretelui toracic, reacții alergice, boli ale sânului, seroame, tromboze venoase, boli ale sistemului imunitar, sindromul şocului toxic.The breast augmentation surgery is performed to increase the breasts size for various reasons: to get a better body contour in women, which for personal reasons feel that their breast size is too small, to correct loss of breast volume after a pregnancy, to achieve a balance between breast size when there are significant differences between the two breasts, as breast reconstruction method for various reasons, replacing breast implants fort medical or cosmetic reasons. Breast augmentation is achieved by inserting breast implants under the glandular tissue or behind the pectoral muscles. Incisions are made so that they are less visible, usually around the lower edge of the areola. The method of insertion and positioning breast implants will depend on patient preferences, anatomy and the plastic surgeon’s recommendations.Every surgical procedure involves some degree of risk: bleeding, infection, capsular contraction, changing of the position of the nipple and skin sensibility, scarring, implant extrusion, skin wrinkling and unevenness in skin appearance, calcification, implant migration, implant surface contamination, deformation of the chest wall, allergic reactions, diseases of the breast, seromas, venous thrombosis, diseases of the immune system, toxic shock syndrome

    Anomalous pressure effect on the magnetic ordering in multiferroic BiMnO3

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    We report the magnetic field dependent dc magnetization and the pressure-dependent (pmax ~ 16 kbar) ac susceptibilities Xp(T) on both powder and bulk multiferroic BiMnO3 samples, synthesized in different batches under high pressure. A clear ferromagnetic (FM) transition is observed at TC ~ 100 K, and increases with magnetic field. The magnetic hysteresis behavior is similar to that of a soft ferromagnet. Ac susceptibility data indicate that both the FM peak and its temperature (TC) decrease simultaneously with increasing pressure. Interestingly, above a certain pressure (9 ~ 11 kbar), another peak appears at Tp ~ 93 K, which also decreases with increasing pressure, with both these peaks persisting over some intermediate pressure range (9 ~ 13 kbar). The FM peak disappears with further application of pressure; however, the second peak survives until present pressure limit (pmax ~ 16 kbar). These features are considered to originate from the complex interplay of the magnetic and orbital structure of BiMnO3 being affected by pressure.Comment: 4 pages,4 figures, publised in Physical Review B 78, 092404/200

    Anomalous cyclotron mass dependence on the magnetic field and Berry’s phase in (Cd₁-x-γZnxMnγ)₃As₂ solid solutions

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    Shubnikov-de Haas (SdH) effect and magnetoresistance measurements of single crystals of diluted II-V magnetic semiconductors (Cd₁-x-γZnxMnγ)₃As₂ (x+γ= 0.4, y=0.04 and 0.08) are investigated in the temperature range T=4.2 ÷ 300 K and in transverse magnetic field B=0 ÷ 25

    RF-Magnetron sputtering of silicon carbide and silicon nitride films for solar cells

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    RF-magnetron nonreactive sputtering method from solid-phase target in argon atmosphere was used for obtaining thin silicon carbide and silicon nitride films, that are used for constructing solar cells based on substrates of single crystal silicon of p-typ

    Structural, optical and electrical conductivity properties of stannite Cu₂ZnSnS₄

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    A precursor powder was obtained from drying the solutions of a mixture of different ratios of Cu, Zn and Sn chloride and thiourea. The Cu2ZnSnS4 (CZTS) samples were prepared from thermal decomposition of the corresponding precursors in vacuum, and were then characterized using scanning emission microscopy, energy dispersive x-ray analysis, x-ray powder diffraction and Raman scatterin

    Temperature influence on the properties of thin Si₃N₄ films

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    Applying Raman spectroscopy, small-angle x-ray scattering, and atomic force microscopy it were studied phase composition and surface morphology of nanoscale films Si₃N₄ (obtained by RF magnetron sputtering

    Incidence and time course of everolimus-related adverse events in postmenopausal women with hormone receptor-positive advanced breast cancer: insights from BOLERO-2.

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    BackgroundIn the BOLERO-2 trial, everolimus (EVE), an inhibitor of mammalian target of rapamycin, demonstrated significant clinical benefit with an acceptable safety profile when administered with exemestane (EXE) in postmenopausal women with hormone receptor-positive (HR(+)) advanced breast cancer. We report on the incidence, time course, severity, and resolution of treatment-emergent adverse events (AEs) as well as incidence of dose modifications during the extended follow-up of this study.Patients and methodsPatients were randomized (2:1) to receive EVE 10 mg/day or placebo (PBO), with open-label EXE 25 mg/day (n = 724). The primary end point was progression-free survival. Secondary end points included overall survival, objective response rate, and safety. Safety evaluations included recording of AEs, laboratory values, dose interruptions/adjustments, and study drug discontinuations.ResultsThe safety population comprised 720 patients (EVE + EXE, 482; PBO + EXE, 238). The median follow-up was 18 months. Class-effect toxicities, including stomatitis, pneumonitis, and hyperglycemia, were generally of mild or moderate severity and occurred relatively early after treatment initiation (except pneumonitis); incidence tapered off thereafter. EVE dose reduction and interruption (360 and 705 events, respectively) required for AE management were independent of patient age. The median duration of dose interruption was 7 days. Discontinuation of both study drugs because of AEs was higher with EVE + EXE (9%) versus PBO + EXE (3%).ConclusionsMost EVE-associated AEs occur soon after initiation of therapy, are typically of mild or moderate severity, and are generally manageable with dose reduction and interruption. Discontinuation due to toxicity was uncommon. Understanding the time course of class-effect AEs will help inform preventive and monitoring strategies as well as patient education.Trial registration numberNCT00863655
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