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Aim. There is an increasing interest in the application of BioACTIVE materials to achieve hard tissue formation and maintain pulp vitality. Mineral trioxide aggregate (MTA) and Biodentine® are BioACTIVE materials used for pulp capping. Recently, dental researchers have produced BioACTIVE glass-incorporated light-curable pulp capping material. The study is aimed at evaluating the subcutaneous connective tissue reactions to MTA, Biodentine®, ACTIVA BioACTIVE Base/Liner. These materials were placed in polyethylene tubes and implanted into the dorsal connective tissue of Sprague Dawley rats. The presence of inflammation, predominant cell type, calcification, and thickness of fibrous connective tissue was recorded by histological examination 7, 30, and 60 days after the implantation procedure. Scores were defined as follows: 0 = none or few inflammatory cells, no reaction; 1 = <25 cells, mild reaction; 2 = 25 to 125 cells, moderate reaction; and 3 = ≥125 cells, severe reaction. Fibrous capsule thickness, necrosis, and formation of calcification were recorded. ANOVA and post hoc Dunnett’s tests were used for statistically analyses ( ）。结果。在水肿，炎症，纤维包膜，坏死方面，在任何材料的任何时间内没有发现显著差异。MTA和Biodentine®表现出比ACTIVA生物活性的第30天更高钙化，差异有统计学显著（ ）。后60天，而钙化未在对照组中看到的那样，它是在测试组中观察到。有控制和其他人之间的统计学差异显著。结论。所有材料均深受在60天的评估期组织的耐受性。一个显着的发现是营养不良性钙化的结缔组织邻近于新开发的生物活性基/衬里材料的存在。因此，这种新的生物活性基/衬里材料可安全地推荐临床医生作为盖髓材料。

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纳米羟基磷灰石（纳米HAP）正在接受相当多的关注牙科用途，以及它们对釉质粘合剂是公认的。不过，也有关于HAP的其他牙科材料的影响未见报道，大部分在这一领域的研究是基于体外designs, neglecting the salivary pellicle-apatite interactions. Thus, this原位试点研究的目的是评估的三个基于羟基磷灰石的解决方案与口服条件下，不同牙科材料表面的影响，它们之间的相互作用。因此，二志愿进行口腔内夹板与釉质和从三个牙科材料固定的样品：钛，陶瓷，和聚甲基丙烯酸甲酯（PMMA）。三HAP水样溶液（5％），用不同的形状和纳米HAP的尺寸（HAP I，II HAP，HAP III）制备。After 3 min of pellicle formation, 10 ml rinse was performed during 30 sec. Rinsing with water served as control. Samples were accessed immediately after rinsing, 30 min and 2 h after rinsing. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to characterize the particles, and SEM evaluated the pellicle-HAP interactions. SEM and TEM results showed a high variation in the size range of the particles applied. A heterogeneous HAP layer was present after 2 h on enamel, titanium, ceramics, and PMMA surfaces under oral conditions. Bridge-like structures were visible between the nano-HAP and the pellicle formed on enamel, titanium, and PMMA surfaces. In conclusion, nano-HAP can adhere not only to enamel but also to artificial dental surfaces under oral conditions. The experiment showed that the acquired pellicle act as a bridge between the nano-HAP and the materials’ surface.

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目的。The present study is aimed at examining the bond strength of cobalt-chromium (Co-Cr) metal frameworks, prepared through different techniques, to a single type of low-temperature porcelain system after the thermal aging process.Methods。使用传统的铸造，CAD / CAM制备了一百二十Co-Cr合金框架标本，和两个不同的商购激光烧结设备，和牙科瓷施加到标本。单一类型的牙科瓷（可乐丽则武牙科公司，东京，日本）的施加至试样。测定亚组后，将样品的一半进行的热老化过程。使用3点弯曲试验的试样的粘结强度进行了评价。使用立体显微镜的断裂试样的表面进行评价。从8组随机选择的样品的金属 - 陶瓷接合区已根据×1000放大倍数观察用SEM。使用由Kolmogorov-Smirnov检验检查所获得的数据的正常性分布。将所得到的本研究的数据进行统计分析用统计软件包程序（SPSS用于Windows 22.0，芝加哥，IL，USA）。结果。有一个统计上的显著差异between CAD/CAM and the other three methods, and the bonding value of the CAD/CAM group was the highest among the groups. Besides, the bond strength between dental porcelain and 4 differently produced metal frameworks was high enough to surpass the acceptable threshold (>25 MPa) according to the ISO 9693. There was no statistically significant difference between thermal aging applied and nonapplied groups.结论。Based on this study, it could be shown that the metal-ceramic bond strength is dependent on the manufacturing method used, but it is independent of the thermal aging application. It was found that the bond strength values of all samples with and without thermal aging application exceeded the minimum acceptable value of 25 MPa recommended by the ISO 9693.

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In this paper, the effect of Er addition (0.2, 0.5, 0.65, 0.8, 1.0, and 1.5 wt. %) on the microstructure evolution and tensile properties of as-cast hypereutectic Al-10Si-0.8Fe alloy was investigated. The phases and their morphologies in these alloys were identified by XRD and SEM equipped with EDX with the help of metallographic analysis techniques; the length of the secondary phase (LSP) and secondary dendrite arm spacing (SDAS) ofα-Al粮食定量。结果表明，第二相（初晶Si，共晶Si，和富铁相）和α-Al grain were significantly refined when the addition of Er increased from 0 to 0.8 wt. %. The mean LSP and SADS values were decreased to a minimum value when the Er addition reached 0.8 wt. %. However, the second phases andα-Al grain became coarser when the level of Er increased more than 0.8 wt. %. The analysis of XRD shows that Er mainly exists in the form of Er₂Si compound. The microstructure modification also has a significant effect on the mechanical properties of the alloy. The yield strength (YS), ultimate tensile strength (UTS), and elongation (EL) increase from 52.86 MPa, 163.84 MPa, and 3.45% to 71.01 MPa, 163.84 MPa, and 5.65%, respectively. From the fracture surface, the promotions of mechanical properties are due to the dispersion and pinning reinforcement caused by the Er₂Si phase.

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Microstructural evolutions of EK61 superalloy during long-term aging until 1000 h at 700°C and 750°C, respectively, are studied by combination of Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM). Impact fracture morphologies after aging for different time are observed by the SEM. The microstructure is found to be relatively stable during aging at 700°C, and the fracture morphologies are characterized by transgranular fracture. At 750°C, the coarsening ofγ 相位超前凹痕的数量的减少，碳化物的在晶界导致晶间断裂的chainization，和的网η晶粒导致的层状裂解步骤在地层内相。显而易见的是，析出相的不稳定影响断口形貌显著。断裂形态和微结构之间的关系促进EK61超合金的服务可靠性的评估。

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Breast cancer can be cured by early diagnosis. Appropriate and effective clinical treatment benefits from accurate pathological diagnosis. However, due to the lack of effective screening and diagnostic imaging methods, early stages of breast cancer often progress to malignant breast cancer. In this study, multiphoton microscopy (MPM) via two-photon excited fluorescence combined with second-harmonic generation was used for identifying the early stages of breast ductal carcinoma. The results showed differences in both cytological features and collagen distribution among normal breast tissue, atypical ductal hyperplasia, low-grade ductal carcinoma in situ, and high-grade ductal carcinoma in situ with microinvasion. Furthermore, three features extracted from the MPM images were used to describe differences in cytological features, collagen density, and basement membrane circumference in the early stages of breast ductal carcinoma. They revealed that MPM has the ability to identify early stages of breast ductal carcinoma label-free, which would contribute to the early diagnosis and treatment of breast cancer. This study may provide the groundwork for the further application of MPM in the clinic.

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