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1.
Laís D. Silva Fernanda C. Puosso Viviane O. Soares Oscar Peitl Filho Simone do R.F. Sabino Francisco C. Serbena Murilo C. Crovace Edgar D. Zanotto 《Ceramics International》2021,47(13):18720-18731
Bioactive glasses and glass-ceramics (GCs) effectively regenerate bone tissue, however most GCs show improved mechanical properties. In this work, we developed and tested a rarely studied bioactive glass composition (24.4K2O-26.9CaO-46.1SiO2-2.6P2O5 mol%, identified as 45S5-K) with different particle sizes and heating rates to obtain a sintered GC that combines good fracture strength, low elastic modulus, and bioactivity. We analyzed the influence of the sintering processing conditions in the elastic modulus, Vickers microhardness, density, and crystal phase formation in the GC. The best GC shows improved properties compared with its parent glass. This glass achieves a good densification degree with a two-step viscous flow sintering approach and the resulting GC shows as high bioactivity as that of the standard 45S5 Bioglass®. Furthermore, the GC elastic modulus (56 GPa) is relatively low, minimizing stress shielding. Therefore, we unveiled the glass sintering behavior with concurrent crystallization of this complex bioactive glass composition and developed a potential GC for bone regeneration. 相似文献
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Simone Grassi Oscar Campuzano Mnica Coll Francesca Cazzato Georgia Sarquella-Brugada Riccardo Rossi Vincenzo Arena Josep Brugada Ramon Brugada Antonio Oliva 《International journal of molecular sciences》2021,22(8)
Inherited cardiomyopathies are frequent causes of sudden cardiac death (SCD), especially in young patients. Despite at the autopsy they usually have distinctive microscopic and/or macroscopic diagnostic features, their phenotypes may be mild or ambiguous, possibly leading to misdiagnoses or missed diagnoses. In this review, the main differential diagnoses of hypertrophic cardiomyopathy (e.g., athlete’s heart, idiopathic left ventricular hypertrophy), arrhythmogenic cardiomyopathy (e.g., adipositas cordis, myocarditis) and dilated cardiomyopathy (e.g., acquired forms of dilated cardiomyopathy, left ventricular noncompaction) are discussed. Moreover, the diagnostic issues in SCD victims affected by phenotype-negative hypertrophic cardiomyopathy and the relationship between myocardial bridging and hypertrophic cardiomyopathy are analyzed. Finally, the applications/limits of virtopsy and post-mortem genetic testing in this field are discussed, with particular attention to the issues related to the assessment of the significance of the genetic variants. 相似文献
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ABSTRACT: This study investigated the effects of 10% (w/v) salt, trisodium phosphate (TSP), sodium tripolyphosphate (STPP), and tetrapotassium pyrophosphate (TKPP) washes on removal of attached Salmonella typhimurium from sterile chicken breast patties, as well as on their injury and survival in a refrigerator for 16 d, in a –20 °C freezer for 10 mo, and after 3 freeze-thaw cycles. S. typhimurium were grown on chicken patties at 20 °C for 20 h, washed, and enumerated by plating on selective and nonselective media. Salt and phosphates washing significantly lowered the survival populations of attached S. typhimurium on patties, but did not cause any significant sublethal injury of attached S. typhimurium , irrespective of storage treatments. The TSP washes showed superior effects of removing and inactivating S. typhimurium compared to other washing treatments. 相似文献
4.
Mirna Suárez-Quiroz Béatrice De Louise Oscar Gonzalez-Rios Michel Barel Bernard Guyot Sabine Schorr-Galindo & Joseph-Pierre Guiraud 《International Journal of Food Science & Technology》2005,40(6):605-611
Roasting coffee led to a drop in the ochratoxin A (OTA) concentration, as measured by the reference method, especially for dark type roasts. The way the beverage was prepared also affected the OTA content, which could paradoxically be higher than that of the initial roasted coffee. Assays on the thermal stability of pure OTA showed that it ought to be found in larger quantities in roasted coffee. This suggested that OTA was masked by reactions with the substrate during roasting. The absence of OTA in green coffee is therefore the best guarantee of safety. 相似文献
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Wastewater treatment technologies suitable for serving large populations are generally reliable and reasonably cost-effective, yet they are almost always financially inappropriate for small communities (< 2,000 p.e.). Comparative cost data suggests that waste stabilization ponds should be an attractive option for small communities, yet perceptions relating to land costs, climate and effluent quality have limited their application in the UK. This paper details typical UK land costs, climate and winter performance data for a pilot-scale waste stabilization pond with various upgrading technologies: system A, two tertiary maturation ponds in series; B, two tertiary maturation ponds in series followed by a reed bed channel; C, a control rock filter; D, an aerated rock filter; and E, a constructed wetland. System D was found to perform best, closely followed by system B. 相似文献
8.
Eva M. Valero Juan L. Nieves Sérgio M. C. Nascimento Kinjiro Amano David H. Foster 《Color research and application》2007,32(5):352-360
Many spectral‐recovery methods using RGB digital cameras assume the underlying smoothness of illuminant and reflectance spectra, and apply low‐dimensional linear models. The aim of the present work was to test whether a direct‐mapping method could be used instead of a linear‐models approach to recover spectral radiances and reflectances from natural scenes with an RGB digital camera and colored filters. In computer simulations, a conventional RGB digital camera with up to three colored filters was used to image scenes drawn from a hyperspectral image database. Three measures were used to evaluate recovery with the direct‐mapping method: goodness‐of‐fit, root‐mean‐square error, and a color‐difference metric. It was found that with two and three filters both spectral radiances and reflectances could be recovered sufficiently accurately for many practical applications. With little increase in computational complexity, an RGB camera and a few colored filters can provide significantly better recovery of natural scenes than an RGB camera alone. © 2007 Wiley Periodicals, Inc. Col Res Appl, 32, 352–360, 2007 相似文献
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