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It is necessary to know the resistance profile of Staphylococcus aureus to better control diabetic foot ulcer infections, to establish rational antibiotic therapy, and to avoid the development of resistant strains. This cross-sectional study evaluated the clinical parameters, virulence, and antimicrobial resistance profiles of S aureus in patients with diabetic foot disease admitted to a public hospital. S aureus strains were identified in patients with diabetes with amputation indication. Infected tissue samples were collected, microbes were isolated and identified. The microbial resistance profile was determined. Samples were also analyzed for biofilm formation and other virulence markers. The 34 individuals examined were mostly men, black, aged 60 years on average, and generally had a low income and education level. Most individuals had type 2 diabetes, and the mean time since diagnosis was 13.9 years. On an SF-36 (the Medical Outcomes Study 36-item short-form health survey) quality-of-life questionnaire, 75% of individuals obtained a score equal to 0 for physical impairment. S aureus specimens from 17 patients were isolated, corresponding to 50% of samples. Five isolates were classified as methicillin-resistant S aureus (MRSA). Molecular typing revealed that 20% of MRSA strains were SCC mec type V and 80% were type I. All isolates were sensitive to doxycycline; 61.5% were resistant to erythromycin, 38.5% to cefoxitin, 30.7% to clindamycin and ciprofloxacin, 23% to meropenem, 15.3% to gentamicin, 38.5% to oxacillin, and 7.7% (one strain) to vancomycin. Regarding biofilm production, 53% of samples were able to produce biofilms, and 84.6% had icaA and/or icaD genes. Additionally, the following enterotoxin genes were identified in the isolates: seb, sec, seg, and sei (5.9%, 5.9%, 11.8%, and 23.9%, respectively) and agr types 1 (5.9%) and 2 (11.8%). Genotypic evaluation made it possible to understand the pathogenicity of S aureus strains isolated from the diabetic foot; laboratory tests can assist in the monitoring of patients with systemic involvement. [ABSTRACT FROM AUTHOR]

This work aims to synthesize the alloy Co62Nb32B6 through a wet-route mechanical alloying using a planetary ball mill. A disc rotation per minute and a ball/powder weight ratio of 350 rpm and 20:1 were used, with a grinding time of 15 h, respectively. The characterization of the Co62Nb32B6 alloy was performed by X-ray diffraction (XRD), examined by scanning electron microscope-energy-dispersive X-ray spectroscopy (SEM–EDS), thermoanalytical techniques (TGA/DTA), vibrating sample magnetometer (VSM), and confirmed by the BET method type IV isotherms with a hysteresis loop for mesoporous materials. The results indicated the evolution of the amorphous phase in the Co62Nb32B6 composition through the mechanical alloying process and exhibited good soft magnetic properties with the addition of the B metalloid element and their excellent unique ferromagnetic properties. Through thermoanalytical analysis (TGA/DTA), it was shown that at higher temperatures, oxidation with a significant increase in mass gain of 19.69% at 865 °C, probably due to the contribution of B in the evolution stability thermal and magnetic in the amorphous phase, respectively. This suggests that the newly developed high-performance amorphous alloy Co62Nb32B6 has great application potential. [ABSTRACT FROM AUTHOR]

This work synthesized and investigated the amorphous alloy Fe73Si22B5 obtained by high-energy milling. The properties of the amorphous alloy Fe73Si22B5 were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) with EDS, Fourier transform infrared spectrometry (FTIR), thermal analysis TGA/DTA, textural analysis by N2 (BET/BJH), and magnetic measurements (VSM). The results confirmed that the Fe73Si22B5 alloy reached the desired amorphization degree and presented IV isotherms with a hysteresis loop for mesoporous materials. The TGA/DTA confirmed that Fe and Si ions are quickly oxidized in the environment with the mass slightly increased to 27.5%. The Fe73Si22B5 exhibited soft magnetic properties with ferromagnetic characteristics. The FTIR spectra exhibit absorption peaks corresponding to the presence of (R)O–H, Fe–O, Si–O, O–Fe–O, and Si–O–Fe groups. This result suggests that the developed high-performance Fe73Si22B5 amorphous alloy has great application potential in various research fields. [ABSTRACT FROM AUTHOR]

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The purpose of this work is to elaborate the amorphous alloy compound Co67Nb25B17 from elementary powders using the planetary ball. The grinding of the amorphous Co67Nb25B17 alloy was carried out for grinding times of 1, 5, 10 and 15 h. In 15 hours, the desired amorphous phase was obtained. The microstructural evolution was followed by the techniques of X-Ray Diffraction (XRD), Scanning Electron Microscopy and Energy Dispersion Spectroscopy (SEM / EDS). Experimental results show that the evolution of the amorphous phase was rapid at a speed of 300 rpm. [ABSTRACT FROM AUTHOR]

The purpose of this work is to elaborate the amorphous alloy compound Co67Nb25B17 from elementary powders using the planetary ball. The grinding of the amorphous Co67Nb25B17 alloy was carried out for grinding times of 1, 5, 10 and 15 h. In 15 hours, the desired amorphous phase was obtained. The microstructural evolution was followed by the techniques of X-Ray Diffraction (XRD), Scanning Electron Microscopy and Energy Dispersion Spectroscopy (SEM / EDS). Experimental results show that the evolution of the amorphous phase was rapid at a speed of 300 rpm. [ABSTRACT FROM AUTHOR]

Aluminum-based alloys containing quasicrystalline phases have good wear resistance due to their low wear coefficient and high hardness. The formation of quasicrystalline phases depends on the composition of the alloy and the imposition of high cooling rates on the molten metal. In the raw state of fusion, presenting β-Al2Fe5(Cu) monoclinic phases, they are present together with the quasicrystalline phase-ω. A careful chemical composition control and an efficient heat treatment are necessary to obtain quasicrystalline phases. The objective of this work was to study the heat treatment in the homogenization of the quasicrystalline alloy Al64Cu27Fe15 obtained by smelting, in a controlled atmosphere. To understand the microstructural evolution, characterizations were made using SEM and XRD. The thermal treatment carried out for 24 hours, to obtain a microstructure with icosahedral phase coexisting with small increases in existing crystalline phases. [ABSTRACT FROM AUTHOR]

Aluminum-based alloys containing quasicrystalline phases have good wear resistance due to their low wear coefficient and high hardness. The formation of quasicrystalline phases depends on the composition of the alloy and the imposition of high cooling rates on the molten metal. In the raw state of fusion, presenting β-Al2Fe5(Cu) monoclinic phases, they are present together with the quasicrystalline phase-ω. A careful chemical composition control and an efficient heat treatment are necessary to obtain quasicrystalline phases. The objective of this work was to study the heat treatment in the homogenization of the quasicrystalline alloy Al64Cu27Fe15 obtained by smelting, in a controlled atmosphere. To understand the microstructural evolution, characterizations were made using SEM and XRD. The thermal treatment carried out for 24 hours, to obtain a microstructure with icosahedral phase coexisting with small increases in existing crystalline phases. [ABSTRACT FROM AUTHOR]

The present work aimed to characterize the microstructure of the icosahedral phase (quasicrystalline phase-φ) of the system with stoichiometric composition of the quasicrystal Al63Cu25Fe12. The ternary alloy with nominal composition of Al63Cu25Fe12 was processed by mechanical alloying (MA) as a viable solid state processing method for producing various metastable and stable quasicrystalline phases. The structural characterization of the obtained samples was performed by X-ray diffraction (XRD) and scanning electron microscopy (SEM), while the elemental composition was determined by dispersive energy spectroscopy (DES). The diffraction patterns of Al63Cu25Fe12 showed the presence of quasicrystalline phase-φ, ω-Al7Cu2Fe, β-Al(Fe, Cu) and λ-Al13Fe4 phases that coexist with the thermodynamic quasicrystalline phase-φ. In icosahedral phase oxidation of aluminum forms a dense layer on the passivating outer most surface of the quasicrystal which causes depletion in both copper and iron. It was observed not only the presence of alumina, γ-Al2O3, but also the formation of hematite and copper oxide in the dense layer. Finally, elemental analysis indicates that during alloy synthesis there is little variation of the ideal composition. The results indicate that alloys with high percentage of icosahedral phase can be obtained by casting in the air. [ABSTRACT FROM AUTHOR]

This paper presents a discussion of the processing and characterization of alloy Co87Nb46B15 produced by rapid solidification, in which characterization techniques such as X-Ray Diffraction (XRD), scanning electron microscopy and Spectroscopy Dispersion Energy (SEM / EDS) and magnetic properties were used, with the study of hysteresis curve. Several researches were done about nanocrystalline materials, especially cobalt-base alloys, because of their thermodynamic stability, characterization and processing. Amorphous alloys have a structure of ultrafine, homogeneous grains with small crystal clusters in amorphous phase. [ABSTRACT FROM AUTHOR]

This paper presents a discussion of the processing and characterization of alloy Co87Nb46B15 produced by rapid solidification, in which characterization techniques such as X-Ray Diffraction (XRD), scanning electron microscopy and Spectroscopy Dispersion Energy (SEM / EDS) and magnetic properties were used, with the study of hysteresis curve. Several researches were done about nanocrystalline materials, especially cobalt-base alloys, because of their thermodynamic stability, characterization and processing. Amorphous alloys have a structure of ultrafine, homogeneous grains with small crystal clusters in amorphous phase. [ABSTRACT FROM AUTHOR]

In this article, we will cover a study of the formation of icosahedral and decagonal phases two quasicrystals Al62Cu25Fe12 and Al65Ni15Co20 oxidation of influence in this alloy. For this purpose, research used the diffraction of X-ray, scanning electron microscopy/energy dispersive spectroscopy, differential scanning calorimetry and thermogravimetric analysis. The results displayed found aspects of morphological structural as well as the surface of the two compositions of quasicrystals, these were prepared and obtained in electric arc furnaces and induction and arc. Oxidation of Al62Cu25Fe12 alloy, intermetallic phases presented with combinations of alloying elements and above 675 °C it was observed that the crystalline phase is stable. In icosahedral phase oxidation of aluminum forms a dense layer on the passivating outer most surface of the quasicrystal which causes depletion in both copper and iron. In Al62Cu25Fe12 nominal composition of oxygen interaction occurs on the surface of symmetry 10 times plane perpendicular vector. The formation of a thin film of aluminum oxide having well-ordered hexagonal structure and with the opposition area decagonal phase with the lateral size of approximately 35Å. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to determine the impact of endovascular surgery versus open vascular technique training in a Brazilian teaching service., Design: Cross-sectional study., Setting: Hospital das Clinicas-Faculty of Medicine-University of Sao Paulo, a tertiary institutional hospital-Brazil., Participants: We reviewed 1,040 arterial operations performed during 2 distinct time periods: January 1995 to December 1996, and January 2006 to December 2007. Based on the disease treated, the procedures were classified into the following 5 groups: abdominal aortic aneurysms (AAA), aorto-iliac obstructive disease (AI), obstructive disease of the femoropopliteal-tibial segment (FP), carotid disease (C), and others (O). The operations were also divided into an endovascular surgery (ES) group and an open surgery (OS) group. We compared the number of open and endovascular procedures for each arterial disease group during both periods., Results: During the 2006-2007 period, 654 patients were treated surgically, whereas over the 1995-1996 period, 386 arterial operations were performed. A significant increase in endovascular procedures (p < 0.001) was found from the 1995-1996 period to the 2006-2007 period (35 vs 351, respectively) in all groups, whereas open surgery showed a slight increase in the number of procedures in the AAA and O groups only. In the 1995-1996 period, OS was the primary surgical method for all groups, but in the 2006-2007 time frame, OS was performed more frequently than ES only in the AAA and O groups. Considering all vascular disease groups, OS was the technique used in 90.9% (351 of 386) of the operations during 1995-1996, whereas in 2006-2007, OS was performed in only 46.3% (303 of 654) of the procedures., Conclusions: The increase in the number of ES observed over the past decade has had little impact on OS procedures performed at our medical center, not bringing harm to open surgical training., (Copyright © 2011 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.)