OBJECTIVEThe aim of this study was to assess the influence of different silicatization protocols with various silane treatment methods on the bond performance to high-translucent zirconia.MATERIALS AND METHODSHigh-translucent zirconia specimens were assigned to five groups according to mechanical surface pretreatment: as-sintered (Con), 0.2 MPa alumina sandblasting (AB2), tribochemical silica coating (TSC), 0.2 and 0.4 MPa glass bead air abrasion (GB2) and (GB4). Each group was subjected to 4 different cementation protocols: Panavia SA Universal (SAU), Panavia SA plus (SAP), silane + SAP (S-SAP), and Universal adhesive + SAP (U-SAP). Tensile bond strength (TBS) was measured after 24 h and 10,000 thermocycling (TC). Surface topography, surface energy, and elemental composition of the abraded zirconia surface analyses were completed. TBS data was analyzed using the Weibull analysis method. Surface roughness and surface energy were compared by one-way ANOVA analysis of variance (α = 0.05).RESULTSAfter 24 h, higher TBS was achieved with all cementation protocols in AB2 and TSC, also, in GB2 with all protocols except U-SAP, and in GB4 with SAU and S-SAP. After aging, GB4/S-SAP, GB2/S-SAP, AB2/U-SAP, and TSC/S-SAP showed the highest bond strength. GB groups showed the lowest surface roughness and highest surface energy.CONCLUSIONGlass bead abrasion achieved the durable bond strength to high-translucent zirconia using a separate silane coupling agent while altered surface chemistry, surface energy, and roughness without effect on morphology.CLINICAL RELEVANCEGlass bead air abrasion is an alternative to alumina sandblasting and tribochemical silica coating and improves bond strength to high translucent zirconia.

2020-08-01·Food Science & Nutrition3区 · 农林科学

Mexican oregano essential oils as alternatives to butylated hydroxytoluene to improve the shelf life of ground beef

3区 · 农林科学

ArticleOA

作者: Hernández‐Martínez, Carlos A. ; Quintero‐Ramos, Armando ; Hume, Michael E. ; Herrera‐Balandrano, Daniela D. ; Sinagawa‐García, Sugey R. ; Gutiérrez‐Soto, Guadalupe ; Cantú‐Valdéz, Jesús A. ; Méndez‐Zamora, Gerardo

AbstractOregano essential oils from Lippia berlandieri Schauer (Lb) and Poliomintha longiflora Gray (Pl) were tested against the antioxidant butylated hydroxytoluene (Bht) to evaluate effects on the shelf life of ground beef (GB) over 7 days of storage at 4°C. The treatments were GB1 = GB control, GB2 = GB +100 mg/kg of Bht, GB3 = GB +100 mg/kg of Lb, and GB4 = GB +100 mg/kg of Pl. Lightness, redness, hardness, and springiness showed differences (p < .05) between treatments and days interaction, which serve as indicators of ground beef preserved quality and consumer acceptance. Mesophilic, psychrophilic, and lactic acid bacteria numbers and antioxidant activity showed differences (p < .05) for treatments and days. Sensory attributes showed no differences between treatments. The oregano oils may provide extended shelf life for packaged meat products treated with these natural additives and hence may be used for ground beef preservation.

2013-01-01·BMC Genomics2区 · 生物学

A Poisson hierarchical modelling approach to detecting copy number variation in sequence coverage data

2区 · 生物学

ArticleOA

作者: Colin J Sutherland ; Susana G Campino ; Nuno Sepúlveda ; Taane G Clark ; Samuel A Assefa ; Arnab Pain

BACKGROUNDThe advent of next generation sequencing technology has accelerated efforts to map and catalogue copy number variation (CNV) in genomes of important micro-organisms for public health. A typical analysis of the sequence data involves mapping reads onto a reference genome, calculating the respective coverage, and detecting regions with too-low or too-high coverage (deletions and amplifications, respectively). Current CNV detection methods rely on statistical assumptions (e.g., a Poisson model) that may not hold in general, or require fine-tuning the underlying algorithms to detect known hits. We propose a new CNV detection methodology based on two Poisson hierarchical models, the Poisson-Gamma and Poisson-Lognormal, with the advantage of being sufficiently flexible to describe different data patterns, whilst robust against deviations from the often assumed Poisson model.RESULTSUsing sequence coverage data of 7 Plasmodium falciparum malaria genomes (3D7 reference strain, HB3, DD2, 7G8, GB4, OX005, and OX006), we showed that empirical coverage distributions are intrinsically asymmetric and overdispersed in relation to the Poisson model. We also demonstrated a low baseline false positive rate for the proposed methodology using 3D7 resequencing data and simulation. When applied to the non-reference isolate data, our approach detected known CNV hits, including an amplification of the PfMDR1 locus in DD2 and a large deletion in the CLAG3.2 gene in GB4, and putative novel CNV regions. When compared to the recently available FREEC and cn.MOPS approaches, our findings were more concordant with putative hits from the highest quality array data for the 7G8 and GB4 isolates.CONCLUSIONSIn summary, the proposed methodology brings an increase in flexibility, robustness, accuracy and statistical rigour to CNV detection using sequence coverage data.

100 项与 GB-4 相关的药物交易

登录后查看更多信息