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Microelectronics packages play a vital role in not only interconnecting the electronic signals from the die to the printed circuit board (PCB), but also in protecting the chips during the manufacturing process and their subsequent service lives. Epoxy molding compound (EMC) is widely used in electronic packaging due to its superior processing capability and low circuit signal delay. However, interfacial delamination is a common problem in encapsulated silicon devices, particularly at the interface between the copper leadframe (LF) pads and the EMC due to the weaker adhesion strength. Accordingly, the present study employs a double cantilever beam (DCB) experimental testing method and a numerical model based on the virtual crack closure technique (VCCT) to investigate the fracture behavior at the EMC/Cu LF interface in a quad flat no leads (QFN) package. The experiments are performed on an MTS-Acumen microforce tester equipped with a load unit capable of applying a force of 0.01 to 1250 N with a displacement resolution of 0.1 μm. The DCB specimens are prepared with a pre-crack length of 12 mm. The validity of the simulation model is confirmed by comparing the predicted values of the critical strain energy release rate (SERR, Gc) between the EMC and the copper LF pads with the experimental observations. In general, the results show that the Gc value provides a useful parameter for evaluating the delamination risk of encapsulated microelectronics packages and assessing the reliability of alternative package architectures. [ABSTRACT FROM AUTHOR]

Braille system is widely used worldwide for communication by visually impaired people. However, there are still some visually impaired people who are unable to learn Braille system due to various factors, such as the age (too young or too old), brain damage, etc. A wearable and low-cost Braille recognition system may substantially help these people recognize Braille or assist them in Braille learning. In this work, we fabricated polydimethylsiloxane (PDMS)-based flexible pressure sensors to construct an electronic skin (E-skin) for the application of Braille recognition. The E-skin mimics human touch sensing function for collecting Braille information. Braille recognition is realized with a neural network based on memristors. We utilize a binary neural network algorithm with only two bias layers and three fully connected layers. Such neural network design remarkably reduces the calculation burden and, thus, the system cost. Experiments show that the system can achieve a recognition accuracy of up to 91.25%. This work demonstrates the possibility of realizing a wearable and low-cost Braille recognition system and a Braille learning-assistance system. [ABSTRACT FROM AUTHOR]

Undifferentiated uveitis (intraocular inflammation, IOI) is an idiopathic sight-threatening, presumed autoimmune disease, accountable for ~ 10% of all blindness in the developed world. We have investigated the association of uveitis with inflammatory bowel disease (IBD) using a mouse model of spontaneous experimental autoimmune uveoretinitis (EAU). Mice expressing the transgene (Tg) hen egg lysozyme (HEL) in the retina crossed with 3A9 mice expressing a transgenic HEL-specific TCR spontaneously develop uveoretinitis at post-partum day (P)20/21. Double transgenic (dTg TCR/HEL) mice also spontaneously develop clinical signs of colitis at ~ P30 with diarrhoea, bowel shortening, oedema and lamina propria (LP) inflammatory cell infiltration. Single (s)Tg TCR (3A9) mice also show increased histological LP cell infiltration but no bowel shortening and diarrhoea. dTg TCR/HEL mice are profoundly lymphopenic at weaning. In addition, dTg TCR/HEL mice contain myeloid cells which express MHC Class II-HEL peptide complexes (MHCII-HEL), not only in the inflamed retina but also in the colon and have the potential for antigen presentation. In this model the lymphopenia and reduction in the absolute Treg numbers in dTg TCR/HEL mice is sufficient to initiate eye disease. We suggest that cell-associated antigen released from the inflamed eye can activate colonic HEL-specific T cells which, in a microbial micro-environment, not only cause colitis but feedback to amplify IOI. [ABSTRACT FROM AUTHOR]

Austenite stability is essentially important in improving the cryogenic toughness of cryogenic Ni steels and guiding the development of Ni-saving cryogenic steels. The austenite stability in the cryogenic Ni steels is influenced by many microstructure features, making it a complicated issue which is lack of a systematic discussion. In this article, the microstructural effects on the thermal and mechanical stability of austenite in the cryogenic Ni steels are reviewed and discussed. The thermal stability of austenite (TSA) will be enhanced by the enrichment of austenite-stabilizing elements in the austenite which decreases the martensite-start (Ms) temperature. The grain refinement enhances the TSA by synergistically increasing the nonchemical driving force for the martensite transformation and the concentrations of austenite-stabilizing elements in the austenite. The excessive increase in the volume fraction of austenite weakens the TSA by decreasing the concentrations of austenite-stabilizing elements in the austenite. The film austenite is usually thermally more stable than the block austenite owing to its higher concentrations of austenite-stabilizing elements. The mechanical stability of austenite (MSA) is also influenced by the concentrations of austenite-stabilizing elements which affect the Ms temperature. The reports on the effect of grain size of austenite on the MSA are inconsistent. Both negligible and important effects of the grain size of austenite on the MSA are analyzed. The grain orientation of austenite affects the MSA via changing the Schmid factor and the additional driving force for the martensite transformation. The orientation which yields a larger value of Schmid factor would exhibit a lower MSA. The MSA is affected by the matrix or the neighboring phase due to the stress and strain partitioning among austenite and other constituent phases. The dislocation multiplication could weaken the MSA by assisting the nucleation and growth of martensite embryo and enhance the MSA by hindering the motion of embryo/austenite interfaces when dislocation density is sufficiently large. Austenite with a combination of a high TSA and a moderate or high MSA is considered to be effective strategies to enhance cryogenic toughness of the cryogenic Ni steels. [ABSTRACT FROM AUTHOR]

Vitrification from physical vapor deposition is known to be an efficient way for tuning the kinetic and thermodynamic stability of glasses and significantly improve their properties. There is a general consensus that preparing stable glasses requires the use of high substrate temperatures close to the glass transition one, Tg. Here, we challenge this empirical rule by showing the formation of Zr-based ultrastable metallic glasses (MGs) at room temperature, i.e., with a substrate temperature of only 0.43Tg. By carefully controlling the deposition rate, we can improve the stability of the obtained glasses to higher values. In contrast to conventional quenched glasses, the ultrastable MGs exhibit a large increase of Tg of ∼60 K, stronger resistance against crystallization, and more homogeneous structure with less order at longer distances. Our study circumvents the limitation of substrate temperature for developing ultrastable glasses, and provides deeper insight into glasses stability and their surface dynamics. [ABSTRACT FROM AUTHOR]

The effects of recovery on the subsequent recrystallization of tantalum were investigated via two-step annealing at two temperatures. Transmission electron microscopy, electron back-scattered diffraction, and X-ray diffraction were employed to determine the respective microstructures and textures after various annealing regimes. The results show that many large grains with {111} orientations are developed when heating at 1573 K without pre-recovery, while pre-recovery can introduce a homogeneous fine microstructure and weaken the texture. This difference can be attributed to the recovery-induced change in nucleation mechanisms. Elongated grains stretch along grain boundaries or locate in the interior of deformed grains, mainly due to the heterogeneous distribution of stored energy. Dislocations characterized by submicron bands in the deformed state evolve into sub-grains during pre-recovery and grow continuously, indicating a homogeneous distribution of dislocation or stored energy after pre-recovery, which can significantly influence subsequent nucleation and grain growth. [ABSTRACT FROM AUTHOR]

In Alzheimer's disease (AD), neurodegenerative signals such as amyloid-beta (Aβ) and the precursors of neurotrophins, outbalance neurotrophic signals, causing synaptic dysfunction and neurodegeneration. The neurotrophin receptor p75 (p75NTR) is a receptor of Aβ and mediates Aβ-induced neurodegenerative signals. The shedding of its ectodomain from the cell surface is physiologically regulated; however, the function of the diffusible p75NTR ectodomain (p75ECD) after shedding remains largely not known. Here, we show that p75ECD levels in cerebrospinal fluid and in the brains of Alzheimer's patients and amyloid-beta precursor protein (APP)/PS1 transgenic mice were significantly reduced, due to inhibition of the sheddase-tumor necrosis factor-alpha-converting enzyme by Aβ. Restoration of p75ECD to the normal level by brain delivery of the gene encoding human p75ECD before or after Aβ deposition in the brain of APP/PS1 mice reversed the behavioral deficits and AD-type pathologies, such as Aβ deposit, apoptotic events, neuroinflammation, Tau phosphorylation and loss of dendritic spine, neuronal structures and synaptic proteins. Furthermore, p75ECD can also reduce amyloidogenesis by suppressing β-secretase expression and activities. Our data demonstrate that p75ECD is a physiologically neuroprotective molecule against Aβ toxicity and would be a novel therapeutic target and biomarker for AD. [ABSTRACT FROM AUTHOR]

The current therapies to treat hepatitis B virus (HBV) infection are limited. Recently, clustered regularly interspaced short palindromic repeat (CRISPR) systems, originally identified in bacteria and archaea, have been found to consist of an RNA-based adaptive immune system that degrades complimentary sequences of invading plasmids and viruses. Here, we studied the effects of the CRISPR/CRISPR-associated Cas9 system that was targeted to the surface antigen (HBsAg)-encoding region of HBV, both in a cell culture system and in vivo. The HBsAg levels in the media of the cells and in the sera of mice were analyzed by a quantitative enzyme-linked immunosorbent assay. The HBV DNA levels were assessed by quantitative PCR and HBsAg expression in mouse livers was assessed by an immunohistochemical assay. The amount of HBsAg secreted in the cell culture and mouse serum was reduced by CRISPR/Cas9 treatment. Immunohistochemistry analyses showed almost no HBsAg-positive cells in the liver tissue of CRISPR/Cas9-S1+X3-treated mice. The CRISPR/Cas9 system efficiently produced mutations in HBV DNA. Thus, CRISPR/Cas9 inhibits HBV replication and expression in vitro and in vivo and may constitute a new therapeutic strategy for HBV infection. [ABSTRACT FROM AUTHOR]

Objective: Animal studies have suggested that betaine, but not choline, may improve body composition, but little evidence is available in humans. We examined the association of serum concentrations of choline and betaine with body composition and fat distribution in adults.Methods: This community-based study recruited 1996 adults (women/men: 1380/616) aged 40-75 years in urban Guangzhou, China. General information and anthropometric measurements were taken, and serum choline and betaine levels were assessed by high-performance liquid chromatography-tandem mass spectrometry between July 2008 and June 2010. After 3.2 years, 1623 of the 1996 participants were measured for fat mass (FM and %FM) over the total body (TB), trunk, limbs, android (A) and gynoid (G) regions. The %FM ratios of the A/G regions and the trunk and limbs were determined by dual energy X-ray absorptiometry.Results: Univariate analyses showed that higher serum betaine levels were significantly associated with lower values of adiposity indices (all P-trends<0.05), except in the case of the %FM at the gynoid area. After adjusting for potential covariates, similar associations were observed. The mean percentage differences between quartiles 4 and 1 of the serum betaine levels were -4.9% (weight), -4.7% (body mass index, BMI), -2.5% (waist circumference), -7.9% (TB FM) and -3.4% (TB %FM). The mean differences in the FM and %FM were much more pronounced at the trunk (-10.0 and -4.5%) or android areas (-10.7 and -4.7%) than those at the limbs (-0.8 and -2.3%) or gynoid areas (-0.6 and -1.4%). Such favorable associations were stronger in men than in women. No significant associations between serum choline and the adiposity indices were observed, except in the cases of body weight and BMI.Conclusions: Greater circulating betaine, but not choline, was dose-dependently associated with better body composition and fat distribution due to a lower FM in the trunk regions in this population. [ABSTRACT FROM AUTHOR]

In this multicentre study, we examined 60 cases of Type II enteropathy-associated T-cell lymphoma (EATL) from the Asia-Pacific region by histological review, immunohistochemistry and molecular techniques. Patients were mostly adult males (median age: 58 years, male:female 2.6:1), presenting with abdominal pain (60%), intestinal perforation (40%) and weight loss (28%). None had a history of coeliac disease and the median survival was only 7 months. Histologically, these tumours could be divided into (i) central tumour zone comprising a monotonous population of neoplastic lymphocytes, (ii) peripheral zone featuring stunted villi and morphologically atypical lymphocytes showing epitheliotropism, and (iii) distant mucosa with normal villous architecture and cytologically normal intra-epithelial lymphocytes (IELs). Characterized by extensive nuclear expression of Megakaryocyte-associated tyrosine kinase (MATK) (87%) and usually a CD8+CD56+ (88%) cytotoxic phenotype, there was frequent aberrant expression of CD20 (24%). T-cell receptor (TCR) expression was silent or not evaluable in 40% but of the remainder, there was predominant expression of TCRαβ over TCRγδ (1.6:1). In keeping with the normal ratio of IEL subsets, CD8+ cases showed predominant CD8αα homodimer expression (77%), regardless of TCR lineage. These tumours constitute a distinct entity from classical EATL, and the pathology may reflect tumour progression from IEL precursors, remnants of which are often seen in the distant mucosa. [ABSTRACT FROM AUTHOR]

Resveratrol, a phytochemical found in various plants and Chinese herbs, is associated with multiple tumor-suppressing activities, has been tested in clinical trials. However, the molecular mechanisms involved in resveratrol-mediated tumor suppressing activities are not yet completely defined. Here, we showed that treatment with resveratrol inhibited cell mobility through induction of the mesenchymal-epithelial transition (MET) in lung cancer cells. We also found that downregulation of FOXC2 (forkhead box C2) is critical for resveratrol-mediated suppression of tumor metastasis in an in vitro and in vivo models. We also identified a signal cascade, namely, resveratrol-∣miRNA-520h-∣PP2A/C-∣Akt → NF-κB → FOXC2, in which resveratrol inhibited the expression of FOXC2 through regulation of miRNA-520h-mediated signal cascade. This study identified a new miRNA-520h-related signal cascade involved in resveratrol-mediated tumor suppression activity and provide the clinical significances of miR-520h, PP2A/C and FOXC2 in lung cancer patients. Our results indicated a functional link between resveratrol-mediated miRNA-520h regulation and tumor suppressing ability, and provide a new insight into the role of resveratrol-induced molecular and epigenetic regulations in tumor suppression. [ABSTRACT FROM AUTHOR]

The enhancer of zeste homolog 2 (EZH2) is upregulated and has an oncogenic role in several types of human cancer. However, the abnormalities of EZH2 and its underlying mechanisms in the pathogenesis of nasopharyngeal carcinoma (NPC) remain unknown. In this study, we found that high expression of EZH2 in NPC was associated closely with an aggressive and/or poor prognostic phenotype (P<0.05). In NPC cell lines, knockdown of EZH2 by short hairpin RNA was sufficient to inhibit cell invasiveness/metastasis both in vitro and in vivo, whereas ectopic overexpression of EZH2 supported NPC cell invasive capacity with a decreased expression of E-cadherin. In addition, ablation of endogenous Snail in NPC cells virtually totally prevented the repressive activity of EZH2 to E-cadherin, indicating that Snail might be a predominant mediator of EZH2 to suppress E-cadherin. Furthermore, co-immunoprecipitation (IP), chromatin IP and luciferase reporter assays demonstrated that in NPC cells, (1) EZH2 interacted with HDAC1/HDAC2 and Snail to form a repressive complex; (2) these components interact in a linear fashion, not in a triangular fashion, that is, HDAC1 or HDAC2 bridge the interaction between EZH2 and Snail; and (3) the EZH2/HDAC1/2/Snail complex could closely bind to the E-cadherin promoter by Snail, but not YY1, to repress E-cadherin. The data provided in this report suggest a critical role of EZH2 in the control of cell invasion and/or metastasis by forming a co-repressor complex with HDAC1/HDAC2/Snail to repress E-cadherin, an activity that might be responsible, at least in part, for the development and/or progression of human NPCs. [ABSTRACT FROM AUTHOR]

Telomere maintenance is essential for cancer growth. Induction of telomere dysfunction, for example, by inhibition of telomeric proteins or telomerase, has been shown to strongly enhance cancer cells' sensitivity to chemotherapies. However, it is not clear whether modulations of telomere maintenance constitute cancer cellular responses to chemotherapies. Furthermore, the manner in which anti-cancer drugs affect telomere function remains unknown. In this study, we show that anthracyclines, a class of anti-cancer drugs widely used in clinical cancer treatments, have an active role in triggering telomere dysfunction specifically in telomerase-positive cancer cells. Anthracyclines interrupt telomere maintenance by telomerase through the downregulation of PinX1, a protein factor responsible for targeting telomerase onto telomeres, thereby inhibiting telomerase association with telomeres. We further demonstrate that anthracyclines downregulate PinX1 by inducing this protein degradation through the ubiquitin-proteasome-dependent pathway. Our data not only reveal a novel action for anthracyclines as telomerase functional inhibitors but also provide a clue for the development of novel anti-cancer drugs based on telomerase/telomere targeting, which is actively investigated by many current studies. [ABSTRACT FROM AUTHOR]

The liquid domain of the Zn-Fe-Al-Mn quaternary system at 460 °C was experimentally investigated. The nature of relevant intermetallic compounds was studied using scanning electron microscopy-energy dispersive x-ray spectroscopy (SEM-EDS). A total of 12 Fe-oversaturated baths with various Mn additions was prepared for the study. When the Al addition was fixed at 0.14 wt.%, δ-FeZn and δ-MnZn were found to co-exist with the liquid phase at low Mn additions. Increasing Mn additions above 1.3 wt.% greatly stabilized δ-MnZn so that it became the sole compound existing in the liquid phase. When the Al addition was fixed at either 0.16 or 0.27 wt.%, η-FeAl was found at low Mn additions but ceased to exist as Mn additions increased above 0.8 wt.%. The current study indicates that the addition of Mn to the bath promotes the formation of δ phases, thus shifting the invariant point of δ/η in the Zn-Fe-Al ternary system to a higher Al level. Based on experimental results, the liquidus surfaces in the Zn-rich corner of the quaternary system at 460 °C were schematically constructed, and implications for practical galvanizing operations were suggested. [ABSTRACT FROM AUTHOR]

By X-ray diffraction combined with Rietveld structure refinement, the crystal structure of FeZn13 was determined experimentally in this study. The results indicated that the structure of FeZn13 is monoclinic and the lattice parameters are a = 1.3408 nm, b = 0.7605 nm, c = 0.5074 nm, and β = 127.206°. It was confirmed that Fe atoms occupy the 2c position (0, 0, 0.5) in space group C2/ m, and the coordinates of Zn atoms at the Zn(1) position are (0.114, 0.5, 0.293), which supports the results from Belin et al. ( Acta Cryst. C 56:267, 2000). In addition, an atomistic calculation was carried out to determine the crystal structure based on the interatomic potentials obtained using the lattice inversion method, and Fe atoms are substituted by Zn atoms in the narrow solubility range of FeZn13, which is the fundamental for studying the solubility and site preference of alloying elements of FeZn13. Good agreement between the experimental results and the theoretical calculations was achieved. [ABSTRACT FROM AUTHOR]

The effects of activation time on the electrochemical capacitance of activated carbon nanotubes (ACNT) have been investigated. The modification of activation time can greatly affect the ACNT electrochemical capacitance, which is carried out by virtue of its effects on ACNT BET specific surface area and graphitized degree. The electrochemical capacitance of ACNT increases by increasing the BET specific surface area and decreasing the graphitized degree. When the ACNT electrochemical capacitance reaches its maximum, there is an optimal value to activation time. [ABSTRACT FROM AUTHOR]

Mechanisms of two F1 hybrids (D46A × DTP-4 and D46A × Dminghui63) of autotetraploid rice (2n = 4x = 48) showing extremely high pollen fertility 87.40% and 85.97%, respectively, seed set 82.00% and 79.00%, respectively and extremely high level of heterosis were analyzed cytologically. The chromosome pairing of D46A × DTP-4 and D46A × Dminghui63 was normal at metaphase I(MI), and had almost no I or III, with an average of 0.020I +14.36 II 6.44rod+7.91ring) +0.01III + 4.80 IV + 0.01VIII and 0.06 I + 17.67 II (11.01rod + 6.67ring)] + 0.06 III +3.10IV+0.01VI, respectively. The most frequent chromosome configurations were 10II+7IV and 12II+bIV. The bivalent frequency was less frequent in hybrids than that in restoring parents, and the same results were gained from univalents, trivalent and multivalents. However, the quadrivalent frequency was significantly higher in hybrids than that in restoring parents at MI. The other meiotic phases progressed normally, except for low percentages of PMCs with lagging chromosomes at AI and low percentages of PMCs with micronuclei at telophaseI (TI) and telophaseII (TII). PMCs with lagging chromosomes at AI and PMCs with micronuclei at TI and TII showed negative correlation between pollen fertility and seed set. Above 90% of the PMCs could form normal microspores, which resulted in the production of viable pollen grains, abnormal microspores were observed including penta-fission and hexa-fission. Based on these results we suggest that the two F1 hybrids had better behaviors of chromosome pairing and genetic stability than autotetraploid rice and other autotetraploid plants ever studied. [ABSTRACT FROM AUTHOR]

This paper concentrates on the design of the optimal measurement placement for the parameter identification of two-dimensional orthotropic composites, which is modeled by the boundary element. From the analysis of the well-posedness of the parameter identification processes using the Levenberg–Marquardt method, a performance indicator and an estimation of the maximum bias of identified parameters are deduced. Based on these results, a method for selecting the optimal measurement placement is proposed. The validity of this method is illustrated by some numerical examples. These examples reveal that the measurement placement has significant influence on identification results. Furthermore, an iterative process of selecting measurement placement is suggested for practical implementation. [ABSTRACT FROM AUTHOR]

Nowadays, numeric control systems or CNC systems are still mainly offered by specific manufacturers, which cannot meet the developing demand of modern technology toward openness, networking, and intelligence. With the decrease of chip cost, the improvement of its performance and the development of fieldbus technology, it becomes easier to develop an open, configurable and intelligent CNC system. In this paper, a new configuration-style CNC system architecture based on CANBUS is presented, including the building of its UML model, the design of communication protocol, the realization of system configures, and the design of software and hardware structures. Finally, an experiment based on configuration-style methods is presented. [ABSTRACT FROM AUTHOR]

Grey mold disease results from Botrytis cinerea, a classical "high-risk" plant pathogenic fungus in meaning of resistance development to fungicides, and its management depends largely on the frequent applications of fungicides. The evolution of resistance to benzimidazole chemicals during 2008 and 2016 was monitored continuously in strawberry greenhouses located in Zhejiang province. Results showed that extensive applications of the mixture of carbendazim and diethofencarb caused the rapid spread of Ben MR subpopulation. The withdraw of this mixture lead to the sharply decrease of Ben MR and re-dominance of Ben HR isolates of B. cinerea with the E198A mutation in β-tubulin gene. The LAMP primers, based on the E198A point mutation, were designed to detect the E198A genotype specifically. HNB (Hydroxynaphthol blue), a metalion indicator, acted as a visual LAMP reaction indicator that turned the violet colored into a sky-blue color. The detection limit of concentration of DNA was 100 × 10−2 ng/μL and this LAMP assay could be applied to detect the E198A genotype with 100% accuracy in strawberry greenhouses of three Province and was more rapid and easier to operate. In summary, we establish a simple and sensitive on-field LAMP assay which can be adopted to determine within 1.5 h whether the benzimidazoles or the mixture of a benzimidazole fungicide and diethofencarb is suitable for management of B. cinerea. [ABSTRACT FROM AUTHOR]

Discusses the phase stability and electrical properties of bismuth titanium oxide thin films by chemical solution deposition. Ferroelectric material with properties for optical memory and piezoelectric devices; Gate insulating material in advanced metal-oxide-semiconductor transistors; Phase becomes unstable at high temperature; Mixed-phase structure.

Plastic deformation of metallic glasses (MGs) has long been considered to be confined to nanoscale shear bands, but recently an affected zone around the shear band was found. Yet, due to technical limitations, the shear-band affected zone (SBAZ), which is critical for understanding shear banding and design of ductile MGs, has yet to be precisely identified. Here, by using magnetic domains as a probe with sufficiently high sensitivity and spatial resolution, we unveil the structure of SBAZs in detail. We demonstrate that shear banding is accompanied by a micrometer-scale SBAZ with a gradient in the strain field, and multiple shear bands interact through the superimposition of SBAZs. There also exists an ultra-long-range gradual elastic stress field extending hundreds of micrometers away from the shear band. Our findings provide a comprehensive picture on shear banding and are important for elucidating the micro-mechanisms of plastic deformation in glasses. Metallic glasses deform along nanoscale shear bands, and while it is known that they affect the neighboring glass regions, exactly how is unclear. Here, the authors use magnetic force microscopy to atomically resolve the shear-band affected zone and show its effects extends much further than previously thought. [ABSTRACT FROM AUTHOR]

In the present study, the microstructure, mechanical property, castability, corrosion behavior and in vitro cytocompatibility of binary Ti-2X alloys with various alloying elements, including Ag, Bi, Ga, Ge, Hf, In, Mo, Nb, Sn and Zr, were systematically investigated, in order to assess their potential applications in dental field. The experimental results showed that all binary Ti-2X alloys consisted entirely α-Ti phase. The tensile strength and microhardness of Ti were improved by adding alloying elements. The castability of Ti was significantly improved by separately adding 2 wt.% Bi, Ga, Hf, Mo, Nb, Sn and Zr. The corrosion resistance of Ti in both normal artificial saliva solution (AS) and extreme artificial saliva solution (ASFL, AS with 0.2 wt.% NaF and 0.3 wt.% lactic acid) has been improved by separately adding alloying elements. In addition, the extracts of studied Ti-2X alloys produced no significant deleterious effect to both fibroblasts L929 cells and osteoblast-like MG63 cells, indicating a good in vitro cytocompatibility, at the same level as pure Ti. The combination of enhanced mechanical properties, castability, corrosion behavior, and in vitro cytocompatibility make the developed Ti-2X alloys have great potential for future stomatological applications. [ABSTRACT FROM AUTHOR]

By X-ray diffraction combined with Rietveld structure refinement, the crystal structure of FeZn13 was determined experimentally in this study. The results indicated that the structure of FeZn13 is monoclinic and the lattice parameters are a = 1.3408 nm, b = 0.7605 nm, c = 0.5074 nm, and β = 127.206°. It was confirmed that Fe atoms occupy the 2c position (0, 0, 0.5) in space group C2/ m, and the coordinates of Zn atoms at the Zn(1) position are (0.114, 0.5, 0.293), which supports the results from Belin et al. ( Acta Cryst. C 56:267, 2000). In addition, an atomistic calculation was carried out to determine the crystal structure based on the interatomic potentials obtained using the lattice inversion method, and Fe atoms are substituted by Zn atoms in the narrow solubility range of FeZn13, which is the fundamental for studying the solubility and site preference of alloying elements of FeZn13. Good agreement between the experimental results and the theoretical calculations was achieved. [ABSTRACT FROM AUTHOR]