Aluminum-Doping Effects on the Electronic States of Graphene Nanoflake: Diffusion and Hydrogen Storage Mechanism

Graphene nanoflakes are widely utilized as high-performance molecular devices due to their chemical stability and light weight. In the present study, the interaction of aluminum species with graphene nanoflake (denoted as GR-Al) has been investigated using the density functional theory (DFT) method to elucidate the doping effects of Al metal on the electronic states of GR. The mechanisms of the diffusion of Al on GR surface and the hydrogen storage of GR-Al were also investigated in detail. The neutral, mono-, di-, and trivalent Al ions (expressed as Al, Al⁺, Al²⁺, and Al³⁺, respectively) were examined as the Al species. The DFT calculations showed that the charge transfer interaction between Al and GR plays an important role in the binding of Al species to GR. The diffusion path of Al on GR surface was determined: the barrier heights of Al diffusion were calculated to be 2.1-2.8 kcal mol^-1, which are lower than Li⁺ on GR (7.2 kcal/mol). The possibility of using GR-Al for hydrogen storage was also discussed on the basis of the theoretical results.

A hydrophilic carbon foam/molybdenum disulfide composite as a self-floating solar evaporator

Solar-driven interfacial evaporation has gained increasing attention as an emerging and sustainable technology for wastewater treatment and desalinization. The carbon/molybdenum disulfide (C/MoS₂) composite has attracted more attention due to its outstanding light absorption capability and optoelectronic properties as a solar steam generator. However, the hydrophobic nature of carbon and MoS₂-based materials hinders their wettability, which is crucial to the effective and facile operation of a solar generator of steam. Herein, a pH-controlled hydrothermal method was utilized to deposit a promising photothermal MoS₂ coating on melamine-derived carbon foams (CFs). The hydrophilic CF/MoS₂ composite, which can easily be floatable on the water surface, is a high-efficiency solar steam evaporator with a rapid increase in temperature under photon irradiation. Due to the localized heat confinement effect, the self-floating composite foam on the surface of water has the potential to produce a significant temperature differential. The porous structure effectively facilitates fast water vapor escape, leading to an impressively high evaporation efficiency of 94.5% under a light intensity of 1000 W m^-2.

Comparative Evaluation of Microtensile Bond Strength of Three Adhesive Systems

Objectives: The aim of this study was to assess the microtensile bond strength of three universal adhesives to dentin and enamel. Materials and Methods: Sixty extracted human third molar teeth were chosen and divided into six groups regarding the adhesive (G-Premio Bond, Clearfil S3 Bond or Single Bond) and tooth surface. All the applied bonding agents were universal adhesives. The teeth were polished and the adhesives were applied; then the teeth were restored with composite resin. The samples were mounted in acrylic resin and sectioned. The specimens were subjected to a universal testing machine and the microtensile bond strength was measured. The failure mode of each specimen was determined under a stereomicroscope. Data were analyzed using two-way ANOVA (α=0.05). Results: The microtensile bond strength of G-Premio Bond to enamel and dentin was 11.79±8.27 and 17.55±9.47 MPa, respectively which was not significantly different from the values in Single Bond group (15.59±10.66 and 17.19±10.09 MPa to enamel and dentin, respectively; P>0.05). However, the values for Clearfil S3 Bond were 7.11±4.23 and 7.88±8.83 MPa to enamel and dentin, respectively, which were significantly lower than the values for G-Premio Bond (P<0.05). Scanning electron microscopic (SEM) images showed that the adhesive failure was dominant in both enamel and dentin groups and in all adhesive systems. Conclusion: G-Premio Bond and Single Bond provided higher microtensile bond strength compared with Clearfil S3 Bond. Universal adhesives with their acceptable performance can be applied in self-etch mode on both enamel and dentin.

Bone Formation Ability and Cell Viability Enhancement of MC3T3-E1 Cells by Ferrostatin-1 a Ferroptosis Inhibitor of Cancer Cells

Recently, ferroptosis has gained scientists’ attention as an iron-related regulated necrosis. However, not many reports have investigated the effect of ferroptosis on bone. Therefore, with the present study, we assessed the effect of ferroptosis inhibition using ferrostatin-1 on the MC3T3-E1 pre-osteoblast cell. Cell images, cell viability, alkaline phosphatase activity test, alizarin red staining, and RUNX2 gene expression using real-time PCR were applied to investigate the effects of ferrostatin and erastin on MC3T3-E1 osteoblast cells. Erastin was used as a well-known ferroptosis inducer reagent. Erastin with different concentrations ranging from 0 to 50 µmol/L was used for inducing cell death. The 25 µmol/L erastin led to controllable partial cell death on osteoblast cells. Ferrostatin-1 with 0 to 40 µmol/L was used for cell doping and cell death inhibition effect. Ferrostatin-1 also displayed a recovery effect on the samples, which had already received the partially artificial cell death by erastin. Cell differentiation, alizarin red staining, and RUNX2 gene expression confirmed the promotion of the bone formation ability effect of ferrostatin-1 on osteoblast cells. The objective of this study was to assess ferrostatin-1’s effect on the MC3T3-E1 osteoblast cell line based on its ferroptosis inhibitory property.

A novel multi-structural reinforced treatment on Ti implant utilizing a combination of alkali solution and bioactive glass sol

OBJECTIVE

Alkali treatment and bioactive glass (BG) sol dip-coating are well-known individual methods for titanium (Ti) surface modification. In this study, a unique combination of alkali treatment and bioactive glass sol dip coating was applied to the Ti substrate, then the mechanical properties and cell responses were investigated.

METHODS

Based on the methods introduced above, the Ti substrate was treated by 6 mL of an NaOH 5 M aqueous solution for 24 h at 60 ̊C; this was followed by adding 1.2 mL of a BG 58S sol to form a novel combined nanostructure network covered by a thin BG layer. For the assessment of the formed coating layer, the morphology, elemental analysis, phase structure, adhesion property and the cell response of the untreated and treated surfaces were investigated.

RESULTS

The BG coating layer was reinforced by the nanostructure, fabricated through the alkali treatment. The results obtained by applying the combined modification method confirmed that the mechanical and biological properties of the fabricated surface demonstrated the highest performance compared to that of the unmodified and individually modified surfaces.

SIGNIFICANCE

The achieved upgrades for this method could be gained from the demanded porous nanostructure and the apatite transformation ability of the alkali treatment. Therefore, the hybridized application of the alkali-BG treatment could be introduced as a promising surface modification strategy for hard-tissue replacement applications.

Echocardiographic evaluation of deformity and enlargement of the canine mitral valve annulus associated with myxomatous degenerative mitral valve disease

INTRODUCTION/OBJECTIVES

Quantitative evaluation of the morphology of the mitral valve annulus (MVA) in dogs with myxomatous mitral valve disease (MMVD) may improve the techniques of mitral valve plasty. This study aimed to compare the MVA morphology on echocardiography in normal dogs and dogs with MMVD and to compare the echocardiographic and intraoperative measurements of the MVA in dogs with MMVD.

ANIMALS, MATERIALS AND METHODS

The study population comprised 59 healthy dogs (control group) and 371 dogs with MMVD (MMVD group). The anterior-posterior diameter and transversal diameter (TD) of the MVA and the aortic annulus diameter were measured by echocardiography to calculate the mitral valve flattening ratio, mitral annulus area (MAA), mitral annulus circumference (MAC), contraction ratio of the MAA and aortic annulus area. In the MMVD group, the mitral annulus diameter (MAD) was macroscopically measured during mitral valve plasty. Areas and lengths were divided by the body surface area (BSA) and √BSA, respectively, for comparative analyses.

RESULTS

The systolic and diastolic anterior-posterior diameter/√BSA, transversal diameter/√BSA, MAA/BSA converted to a natural logarithm (Ln(MAA/BSA)), and MAC/√BSA was significantly higher in the MMVD group than the control group, whereas flattening ratio values and contraction ratio of the MAA was significantly lower. Neither the aortic annulus diameter /√BSA nor the Ln(aortic annulus area/BSA) significantly differed between groups. In the MMVD group, diastolic MAC/√BSA and MAA/BSA correlated significantly with the MAD/√BSA.

CONCLUSIONS

The MVA is larger and rounder in dogs with MMVD than controls. Two-dimensional echocardiographic measures of MAA and MAC correlate well with intraoperative measures of MAD.

Fabrication of bioactive glass coating on pure titanium by sol-dip method: Dental applications

This study aimed to assess the mechanical and biological properties of bioactive glass (BG) coating on titanium (Ti). Bioinert Ti substrates were coated by BG to induce bioactivity to the surface. The sol-gel derived BG 58S sol was successfully prepared and coated on the abraded and blasted Ti surface using the sol-dip method. The characterization and cell study for all substrates' surface was carried out. Adhesion test confirmed that a firmly adhered BG coating layer was formed on the abraded and blasted Ti. The measured bonding strength between the coating and the blasted Ti substrate was the highest among all samples, which was 41.03±2.31 MPa. In-vitro cell viability and alkaline phosphatase activity (ALP) tests results also showed that BG coating on the Ti substrate improved the biological properties of the surface. The BG sol-dip coating method could be used to fabricate Ti substrate with a bioactive surface.

A novel coating layer on zirconia using modified zinc phosphatizing method

Yttria doped ZrO₂ was deposited using an acidic zinc phosphatizing solution and the hydrothermal treatment. The coating was analyzed using a field emission-scanning electron microscope (FE-SEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). A piston on three balls (ISO 6872) was used for the measurement of biaxial flexural strength. MC3T3-E1 cells attachment was evaluated by SEM, and cell proliferation were assessed using MTS assay™. SEM images confirmed that the zinc phosphate coating layer was successfully prepared and fully covered the surface. The measured adhesive strength of the coating was 79.11 MPa. In vitro cell study indicated that the coated sample had better cell morphology and proliferation. XRD and EDS analysis revealed that the crystalline coating structure indexed as zinc phosphate (hopeite) and the substrate was assigned as zirconia. The flexural strength test showed that the strength of zirconia before and after hydrothermal treatment was not affected.

Physical and mechanical characteristics of short fiber-reinforced resin composite in comparison with bulk-fill composites

PURPOSE

The objective of this study was to evaluate the physical and mechanical properties of a short fiber-reinforced resin composite: everX-Posterior and compare it with two bulk-fill composites, namely, Filtek Bulk-fill and Beautifil-Bulk, which are intended for large posterior restorations.

METHODS

Investigated properties were flexural strength, flexural modulus, surface roughness, volumetric shrinkage and depth of cure. Scanning electron microscopy images of each specimen after the flexural test were used for cross-sectional comparison. Results were analyzed using ANOVA following Tukey post-hoc test.

RESULTS

Flexural strength of everX-Posterior was comparable with two other resin composites, showing higher flexural modulus. EverX-Posterior showed the highest surface roughness after polishing and the lowest volumetric shrinkage (2.29%) among all composites used in this study. Data also showed that the everX-Posterior depth of cure was 4.24 mm, which was the highest among the three groups.

CONCLUSION

Based on the results of this study, it was concluded that everX-Posterior as a short fiber-reinforced composite showed improvements and satisfactory performance in mechanical and physical properties, which make it a reliable base material candidate for large posterior restorations.

Lipofuscin in keratinocytes: Production, properties, and consequences of the photosensitization with visible light

A dysfunction in the mitochondrial-lysosomal axis of cellular homeostasis is proposed to cause cells to age quicker and to accumulate lipofuscin. Typical protocols to mediate lipofuscinogenesis are based on the induction of the senescent phenotype either by allowing many consecutive cycles of cell division or by treating cells with physical/chemical agents such as ultraviolet (UV) light or hydrogen peroxide. Due to a direct connection with the physiopathology of age-related macular degeneration, lipofuscin that accumulates in retinal pigment epithelium (RPE) cells have been extensively studied, and the photochemical properties of RPE lipofuscin are considered as standard for this pigment. Yet, many other tissues such as the brain and the skin may prompt lipofuscinogenesis, and the properties of lipofuscin granules accumulated in these tissues are not necessarily the same as those of RPE lipofuscin. Here, we present a light-induced protocol that accelerates cell aging as judged by the maximization of lipofuscinogenesis. Photosensitization of cells previously incubated with nanomolar concentrations of 1,9-dimethyl methylene blue (DMMB), severely and specifically damages mitochondria and lysosomes, leading to a lipofuscin-related senescent phenotype. By applying this protocol in human immortalized non-malignant keratinocytes (HaCaT) cells, we observed a 2.5-fold higher level of lipofuscin accumulation compared to the level of lipofuscin accumulation in cells treated with a typical UV protocol. Lipofuscin accumulated in keratinocytes exhibited the typical red light emission, with excitation maximum in the blue wavelength region (~450 nm). Fluorescence lifetime image microscopy data showed that the keratinocyte lipofuscin has an emission lifetime of ~1.7 ns. Lipofuscin-loaded cells (but not control cells) generated a substantial amount of singlet oxygen (¹O₂) when irradiated with blue light (420 nm), but there was no ¹O₂ generation when excitation was performed with a green light (532 nm). These characteristics were compared with those of RPE cells, considering that keratinocyte lipofuscin lacks the bisretinoids derivatives present in RPE lipofuscin. Additionally, we showed that lipofuscin-loaded keratinocytes irradiated with visible light presented critical DNA damages, such as double-strand breaks and Fpg-sensitive sites. We propose that the DMMB protocol is an efficient way to disturb the mitochondrial-lysosomal axis of cellular homeostasis, and consequently, it can be used to accelerate aging and to induce lipofuscinogenesis. We also discuss the consequences of the lipofuscin-induced genotoxicity of visible light in keratinocytes.

The effect of annealing temperature on microstructure and mechanical properties of dissimilar laser welded superelastic NiTi to austenitic stainless steels orthodontic archwires

Annealing after welding is a common operational process to improve the mechanical properties of metallic joints through releasing residual stresses in the weld zone. In this study, the effect of post weld annealing on the microstructure and mechanical properties of dissimilar laser-welds for orthodontic archwires of NiTi alloy to austenitic stainless steel has been investigated. In order to do this, the laser-welded wires were annealed at temperatures of 100, 200, and 300 °C for 1 h and then they were quenched in water. Results show that annealing at 100 °C does not affect the microstructure and mechanical properties of joints but post weld heat treatment at 200 °C ends in an increase in the tensile strength to an order of 1.91 times of the strength of as welded (non-heat-treated) joints. Also, precipitation and increase of intermetallic compounds, such as Cr₂Ti, and Fe₂Ti, at the weld zone during heat treatment at 300 °C, results in a reduction in the mechanical properties of joints. Therefore, post-weld annealing is an effective process on improving mechanical properties of dissimilar joints of these two alloys. However, a suitable heat-treatment temperature is needed in order to achieve desired results.

Size- and Morphology-Controlled Preparation of Surface-Modified Water-Dispersible Fullerene Nanoparticles for Bioapplications

In this study, we investigated water-dispersible surface modification for size- and shape-controlled fullerene nanoparticles (C₆₀P) based on a condensation reaction with di-amino alkane. This modification provided for water dispersibility of C₆₀P and the capability for secondary modification as well. The resultant C₆₀P particles have several useful physical properties: water-dispersibility for ease of injection; fluorescence for detection and quantification; and a characteristic morphology to assist identification. These properties will widely extend the applications of these particles, especially into the biological fields of bioimaging and drug delivery.

Conversion of a conventional superconductor into a topological superconductor by topological proximity effect

Realization of topological superconductors (TSCs) hosting Majorana fermions is a central challenge in condensed-matter physics. One approach is to use the superconducting proximity effect (SPE) in heterostructures, where a topological insulator contacted with a superconductor hosts an effective p-wave pairing by the penetration of Cooper pairs across the interface. However, this approach suffers a difficulty in accessing the topological interface buried deep beneath the surface. Here, we propose an alternative approach to realize topological superconductivity without SPE. In a Pb(111) thin film grown on TlBiSe₂, we discover that the Dirac-cone state of substrate TlBiSe₂ migrates to the top surface of Pb film and obtains an energy gap below the superconducting transition temperature of Pb. This suggests that a Bardeen-Cooper-Schrieffer superconductor is converted into a TSC by the topological proximity effect. Our discovery opens a route to manipulate topological superconducting properties of materials.

Realizing topological superconductivity is essential for applicable fault-tolerant quantum computation. Here, Trang et al. report migration of Dirac-cone from TlBiSe₂ substrate to top surface of superconducting Pb film due to topological proximity effect, suggesting realization of topological superconductivity.

P11 The difference in the serial change of indoxyl sulfate after catheter ablation among atrial fibrillation patients with or without chronic kidney disease

Introduction

It is well known that catheter ablation (CA) for patients with atrial fibrillation (AF) improves their renal function. However, the precise mechanism of improving a renal function, such as a transition of the uremic toxin is unclear.

Purpose

Indoxyl sulfate (IS), a protein-bound uremic toxin, induces chronic kidney disease (CKD) and AF. This study aimed to investigate the transition of serum IS level in the AF patients with and without CKD after CA.

Methods

A total of 138 consecutive AF patients who underwent CA and maintained sinus rhythm were prospectively enrolled (age 65.5 ± 10.7 years, paroxysmal AF 67.4%). Patients were divided into 4 groups (non-CKD/low-IS:68, non-CKD/high-IS:28, CKD/low-IS:13, CKD/high-IS:29). CKD was defined as CKD stage III (estimated glomerular filtration rate (eGFR) 30-60 ml/min/1.73m2), and high-IS was defined according to the mean of IS (IS≥1.1 μg/ml) before CA. Plasma IS levels and eGFR were determined before and at 1 year after CA. We evaluated the relationship between the IS and eGFR after CA among the 4 groups.

Results

CA significantly improved the eGFR in patients with CKD (from 50.2 ± 5.7 to 55.4 ± 10.8 ml/min/1.73m2, p &lt; 0.001). The serum IS level in the patients with non-CKD/high-IS was significantly decreased (from 1.7 ± 0.7 to 1.1 ± 0.6 μg/ml, p &lt; 0.001). However, the serum IS level in the patients with CKD/high-IS was not improved (from 1.9 ± 0.9 to 1.7 ± 0.7 μg/ml, p = 0.22) and significantly higher than that in the others (p &lt; 0.001), regardless of improving their eGFR (Figure). Furthermore, the multiple regression analysis revealed that the ΔIS, between before and after CA, was independent of eGFR.

Conclusion

The change of IS in the patients with CKD was significantly different from that in those without CKD. In the patients with CKD, CA improved their eGFR, however, the serum level of IS, a protein-bound uremic toxin, was not improved after CA.

Abstract P11 Figure. Serial Change of eGFR and IS

Evaluation of viscoelastic properties, hardness, and glass transition temperature of soft denture liners and tissue conditioner

Soft denture liners and tissue conditioners are widely used for the denture patients to cushion masticatory force and condition abused tissues, respectively. This study assessed methods for the evaluation of the viscoelasticity and glass transition temperature (T_g) of the silicone permanent soft liner, acrylic permanent soft liner, and tissue conditioner. Three rheological parameters of storage modulus (E'), loss modulus (E''), and loss tangent ([Formula: see text]), T_g, and hardness were determined using dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), and the Shore A0 hardness test. Five specimens were measured for each material. The time-temperature superposition principle was applied to produce master curves of E', E'', and [Formula: see text] for the tested materials at a reference temperature of 37 °C. The acrylic permanent soft liner and tissue conditioner exhibited viscoelastic behavior and sensitivity to frequency, especially at lower frequencies. The silicone permanent soft liner showed elastic behavior and was frequency-independent. T_g for the acrylic permanent soft liner was higher than that for the tissue conditioner, which in turn was higher than that for the silicone permanent soft liner for both DMA and DSC. In DMA, a higher frequency led to higher T_g values. A positive linear relationship was found between Shore A0 hardness and E' values, but not E'' and [Formula: see text] values. Shore hardness reflects elasticity, but not viscosity. The results of the present study can be used to improve methods for evaluating the viscoelasticity and T_g of soft denture liners and tissue conditioners.

P5623Plaque characteristics, slow flow during percutaneous coronary intervention, and clinical outcomes of irregular protrusion by optical coherence tomography

Introduction

In pathological studies, penetration of the lipid core into the stent strut is associated with neointimal growth and stent thrombosis. Irregular protrusion on optical coherence tomography (OCT) is associated with clinical events and target lesion revascularization. However, there are few reports about the relationship among irregular protrusion, plaque characteristics, and slow flow during percutaneous coronary intervention. We investigated clinical and procedure characteristics, plaque characteristics, slow flow after stent implantation, and clinical outcomes with irregular protrusion by using OCT.

Methods

Eighty-four lesions in 76 patients undergoing OCT before percutaneous coronary intervention were evaluated. Irregular protrusion was defined as protrusion of material with an irregular surface into the lumen between stent struts with a maximum height of ≥100 μm. Major adverse clinical outcomes were defined as death, acute myocardial infarction, acute coronary syndrome, or target lesion revascularization.

Results

Lesions with irregular protrusion were found in 56% (47/84). Compared with lesions without irregular protrusion, those with irregular protrusion had significantly higher low-density lipoprotein cholesterol (LDL-C) levels (108±31 mg/dL vs. 95±25 mg/dL, P=0.044); a tendency toward decreased use of statins (44% [19/43] vs. 67% [22/33], P=0.065); significantly larger reference vessel diameter (3.12±0.53 mm vs. 2.74±0.63 mm, P=0.004); significantly larger stent diameter (3.23±0.43 mm vs. 3.00±0.49 mm, P=0.025); a tendency toward longer total stent length (29.3±14.2 mm vs. 23.7±11.4 mm, P=0.056); significantly larger maximum balloon diameter (3.56±0.55 mm vs. 3.22±0.63 mm, P=0.010); significantly higher incidence of slow flow after stent implantation (38% [18/47] vs. 11% [4/37], P=0.006); significantly higher ΔTIMI flow from pre-stenting to post-stenting (0.4±0.6 vs. 0.1±0.3, P=0.009); significantly higher incidence of lipid-rich plaque (70% [33/47] vs. 35% [13/37], P=0.002); thin-cap fibroatheromas (TCFAs: 49% [23/47] vs. 5% [2/37], P<0.001); plaque rupture (40% [19/47] vs. 16% [6/37], P=0.018); macrophage accumulation (51% [24/47] vs. 24% [9/37], P=0.015); internal running vasa vasorum (51% [24/47] vs. 11% [4/37], P<0.001); thrombus (32% [15/47] vs. 3% [1/37], P<0.001); and a tendency higher incidence of one-year adverse clinical outcomes (12% [5/43] vs. 0% [0/33], P=0.075: log rank). The multivariable analysis showed that TCFA was an independent predictor of irregular protrusion (odds ratio 9.00, 95% CI 1.32–61.36, P=0.025).

Conclusions

Irregular protrusion on OCT was associated with high plaque vulnerability, higher LDL-C, less frequent use of statin, larger vessel diameter, longer total stent length, slow flow after stent implantation, and one-year adverse clinical outcomes.

The effect of the nano- bioglass reinforcement on magnesium based composite

Nano-bioceramic particles serving as a reinforcement can improve the mechanical and biological properties of magnesium implants, but they might have some side effects, that must be addressed. In this research, magnesium composites including 10 wt% nano-bioglass (nBG) were fabricated using powder metallurgy (PM10) and spark plasma sintering (SPS10) methods for bone reconstruction purposes. The results of the compression test indicated that the SPS10 sample had higher mechanical properties, in comparison to the PM10 sample, and nBG had more reinforcing effect on the mechanical properties of magnesium matrix. X-ray difractometery indicated that nBG was chemically reacted with magnesium in the PM10 sample, and resulted in some extra phases (MgO and Mg₂Si) formation, while there was no detectable extra phases in the SPS10 sample. However, a higher in vitro degradation rate was observed for PM10 sample, because of multi-phase formation at the magnesium matrix. To inhibit the chemical reaction between magnesium and nBG kinetically, a short time sintering process can be, therefore, recommended.

Bioactive glass coating on zirconia by vacuum sol-dipping method

In order to the preparation of biodegradable, bioactive and strongly adhered coating layer to the bioinert zirconia substrate, a bioactive glass (BG) was successfully coated on the zirconia plates. To achieve this goal, the zirconia plates dipped into the 45S5 BG sol in the vacuum chamber (vacuum sol-dipping method) followed by sintering to fabricate a strongly adhered BG coating on the zirconia plates. The parameters such as surface morphology and BG coating coverage ability on the zirconia plates have been assessed before and after coating with 45S5 BG. Phase structure of the BG coating based on the X-ray diffraction (XRD) result could be indexed as Na₄Ca₄(Si₆O₁₈). The interfacial adhesive strength between the zirconia substrate and BG coating layer was higher than the measured adhesive strength (55±7 MPa). The viability results approved the satisfying conclusion for the offered coating method on the zirconia substrates.

Assessment of characteristics and cytotoxic effects of 316L stainless steel coated with a new titanium oxide nano-structure coating method

In order to fabricate the TiO₂ nano-structure coating on the Ti-free stainless steel with good adhesion, commercially obtained 316L stainless steel (316L SS) plates were chemically treated by KOH aqueous solution including TiH₂ powder at 60ºC for 3 days in an oil bath shaker, and subsequently heated up to 550-800ºC under the air atmosphere. The crystal structure, color, adhesive strength and cytotoxic effects of coating were investigated. Fiber-like hydrogen titanate nano-structures were formed on the 316L SS surface and made a fine network. X-ray diffraction (XRD) patterns showed that hydrogen titanate phase converted to anatase and rutile after heat treatment above 550ºC. The heat treated sample at 800ºC for 1 h showed the highest adhesive strength and the lowest cytotoxicity. The alkali treatment method in this study is expected to be used on the other Ti-free metals with further research.

Nodeless superconductivity in the cage-type superconductor Sc5Ru6Sn18 with preserved time-reversal symmetry

We report the single-crystal synthesis and detailed investigations of the cage-type superconductor Sc₅Ru₆Sn₁₈, using powder x-ray diffraction (XRD), magnetization, specific-heat and muon-spin relaxation (µSR) measurements. Sc₅Ru₆Sn₁₈ crystallizes in a tetragonal structure (space group I4₁/acd) with lattice parameters a  =  1.387(3) nm and c  =  2.641(5) nm. Both DC and AC magnetization measurements prove the type-II superconductivity in Sc₅Ru₆Sn₁₈ with T _c  ≈  3.5(1) K, a lower critical field [Formula: see text]  =  157(9) Oe and an upper critical field, [Formula: see text]  =  26(1) kOe. The zero-field electronic specific-heat data are well fitted using a single-gap BCS model, with [Formula: see text]  =  0.64(1) meV. The Sommerfeld constant γ varies linearly with the applied magnetic field, indicating s-wave superconductivity in Sc₅Ru₆Sn₁₈. Specific-heat and transverse-field (TF) µSR measurements reveal that Sc₅Ru₆Sn₁₈ is a superconductor with strong electron-phonon coupling, with TF-µSR also suggesting a single-gap s-wave character of the superconductivity. Furthermore, zero-field µSR measurements do not detect spontaneous magnetic fields below T _c, hence implying that time-reversal symmetry is preserved in Sc₅Ru₆Sn₁₈.

Effects of heat-treated Lactobacillus crispatus KT-11 strain consumption on improvement of oral cavity environment: a randomised double-blind clinical trial

Heat-treated lactic acid bacteria is added to some foods because it is easier to store and transport, and have less interference with other food ingredient compared with living lactic acid bacteria. We have reported that oral administration of heat-treated Lactobacillus crispatus KT-11 strain (KT-11) suppressed the symptoms of periodontal disease in mice orally infected with Porphyromonas gingivalis. However, the preventive effect of KT-11 on periodontal disease in human is unclear. The aim of this randomised double-blind clinical trial was to examine the effects of KT-11 consumption on the oral environment in healthy volunteers. Sixteen healthy volunteers were randomly assigned to two groups (KT-11 or placebo), and they consumed a KT-11 food tablet (1.2×1010 KT-11 cells) or a placebo food tablet (without KT-11) every day for 4 weeks. Clinical parameters including numbers of major periodontopathic bacteria in saliva, plaque score, gum conditions, and oral mucosal fluid level were evaluated at weeks 0 and 4. Amount of change in P. gingivalis numbers decreased in the KT-11 group compared to that in the placebo group at week 4. Female participants in the KT-11 group had decreased plaque scores, reddish tinge, and gingival swelling scores compared to those in the placebo group at week 4. Furthermore, male participants in the KT-11 group demonstrated increased oral mucosa fluid scores. These clinical findings suggest that daily KT-11 intake can prevent periodontal disease through the improvement of oral conditions.

The effect of abrading and cutting instruments on machinability of dental ceramics

The aim was to investigate the effect of machining instruments on machinability of dental ceramics. Four dental ceramics, including two zirconia ceramics were machined by three types (SiC, diamond vitrified, and diamond sintered) of wheels with a hand-piece engine and two types (diamond and carbide) of burs with a high-speed air turbine. The machining conditions used were abrading speeds of 10,000 and 15,000 r.p.m. with abrading force of 100 gf for the hand-piece engine, and a pressure of 200 kPa and a cutting force of 80 gf for the air-turbine hand-piece. The machinability efficiency was evaluated by volume losses after machining the ceramics. A high-abrading speed had high-abrading efficiency (high-volume loss) compared to low-abrading speed in all abrading instruments used. The diamond vitrified wheels demonstrated higher volume loss for two zirconia ceramics than those of SiC and diamond sintered wheels. When the high-speed air-turbine instruments were used, the diamond points showed higher volume losses compared to the carbide burs for one ceramic and two zirconia ceramics with high-mechanical properties. The results of this study indicated that the machinability of dental ceramics depends on the mechanical and physical properties of dental ceramics and machining instruments. The abrading wheels show autogenous action of abrasive grains, in which ground abrasive grains drop out from the binder during abrasion, then the binder follow to wear out, subsequently new abrasive grains come out onto the instrument surface (autogenous action) and increase the grinding amount (volume loss) of grinding materials.

Alginate Microcapsules as Nutrient Suppliers: An In Vitro Study

Objective

Alginate, known as a group of anionic polysaccharides extracted from seaweeds, has attracted the attention of researchers because of its biocompatibility and degradability properties. Alginate has shown beneficial effects on wound healing as it has similar function as extracellular matrix. Alginate microcapsules (AM) that are used in tissue engineering as well as Dulbecco’s modified Eagle’s medium (DMEM) contain nutrients required for cell viability. The purpose of this research was introducing AM in medium and nutrient reagent cells and making a comparison with control group cells that have been normally cultured in long term.

Materials and Methods

In this experimental study, AM were shaped in distilled water, it was dropped at 5 mL/hours through a flat 25G5/8 sterile needle into a crosslinking bath containing 0.1 M calcium chloride to produce calcium alginate microspheres. Then, the size of microcapsules (300-350 µm) were confirmed by Scanning Electron Microscopy (SEM) images after the filtration for selection of the best size. Next, DMEM was injected into AM. Afterward, adipose- derived mesenchymal stem cells (ADSCs) and Ringer’s serum were added. Then, MTT and DAPI assays were used for cell viability and nucleus staining, respectively. Also, morphology of microcapsules was determined under invert microscopy.

Results

Evaluation of the cells performed for spatial media/microcapsules at the volume of 40 µl, showed ADSCs after 1-day cell culture. Also, MTT assay results showed a significant difference in the viability of sustained-release media injected to microcapsules (P<0.05). DAPI staining revealed living cells on the microcapsules after 1 to 7-day cell culture.

Conclusion

According to the results, AM had a positive effect on cell viability in scaffolds and tissue engineering and provide nutrients needed in cell therapy.

Temporal mapping of photochemical reactions and molecular excited states with carbon specificity

Photochemical reactions are essential to a large number of important industrial and biological processes. A method for monitoring photochemical reaction kinetics and the dynamics of molecular excitations with spatial resolution within the active molecule would allow a rigorous exploration of the pathway and mechanism of photophysical and photochemical processes. Here we demonstrate that laser-excited muon pump-probe spin spectroscopy (photo-μSR) can temporally and spatially map these processes with a spatial resolution at the single-carbon level in a molecule with a pentacene backbone. The observed time-dependent light-induced changes of an avoided level crossing resonance demonstrate that the photochemical reactivity of a specific carbon atom is modified as a result of the presence of the excited state wavefunction. This demonstrates the sensitivity and potential of this technique in probing molecular excitations and photochemistry.

Effect of sintering temperature rise from 870 to 920°C on physicomechanical and biological quality of nano-hydroxyapatite: An explorative multi-phase experimental in vitro/vivo study

Hydroxyapatite (HA) is a proper scaffold for bone repair, however, it is not of excellent mechanical properties. Most previous studies on the effect of temperature increases were in vitro and had assessed merely improvements of HA's physicomechanical quality. This in vitro/vivo study investigated the effect of temperature increases from 870 to 920°C on physicomechanical and biological quality of Nano-HA. Forty experimentally produced HA disks sintered at 870 to 920°C were prepared (n=20×2). Disks were subjected to Vickers microindentation test (1 disk from each group divided into 4 quarters), Fourier transform infrared spectroscopy (1 disk), X-ray diffraction (XRD) [1 disk together with non-sintered HA], field emission scanning electron microscopy (FSEM, 1 disk from each group together with non-sintered HA), cell seeding and SEM assessment (2 disks), MTT assay over 4 different time periods (16 quadrants of 4 disks from each group), 6 one-thirds of 2 disks from each group for immunocytochemical (ICC) assay, and 8 disks from each group [as well as non-sintered HA] for the animal study (implantation in 4 sockets in 8 rabbits [32 specimens], histomorphometry, and computerized tomography) over two time periods. Quantitative data were analyzed statistically (α=0.05). Vickers microhardness increased from 63.7±11.9 in the 870 group to 153.4±104.7 in the 920 group (P=0.057). XRD indicated more regular crystal patterns in sintered groups compared to non-sintered nanoHA. FSEM showed larger crystals in the 920 group compared to 870 and non-sintered nanoHA. Expression of osteocalcin, osteonectin, and RUNX2 genes were more visible in ICC samples of the 920HA group. In MTT, cell numbers increased in all groups significantly (P=0.000), with no between-group differences (P>0.3). In rabbit experiments, the extent of 'newly formed bone' increased significantly over time (two-way ANOVA, P=0.000), reaching 39.5%, 46.4%, and 77.5% in the groups non-sintered HA, 870, and 920, respectively. The 920°C-sintered nanoHA induced the highest bone formation (P=0.000). Increasing the temperature of nanoHA sintering from 870 to 920°C can improve its physicomechanical properties and bone formation potential.

Evaluation of five primers and two opaque resins for bonding ceria-stabilized zirconia/alumina nanocomposite

The purpose of this study was to evaluate the effect of five primers [Super-Bond C&B Monomer (SB), Clearfil Ceramic Primer, Alloy Primer, M.L. Primer, and AZ Primer] and two undercoating opaque resins [Super-Bond C&B (S-opaque) and Ceramage Pre-opaque (C-opaque)] on the bonding of a resin composite veneering material to a ceria-stabilized tetragonal zirconia polycrystals/alumina nanocomposite (Ce-TZP/Al₂O₃). Disk-shaped specimens of Ce-TZP/Al₂O₃ were sandblasted with alumina and primed. The undercoating opaque resins and resin composites were subsequently applied to the specimen, and then light cured. After 5000 thermocycles at 4°C and 60°C, shear bond strengths were determined. Data were analyzed using analysis of variance, Tukey–Kramer honest significant difference test, and Student t test (n = 10, α = 0.05). With the exception of SB/S-opaque, all S-opaque groups exhibited significantly higher bond strengths than C-opaque groups. The use of S-opaque resin is recommended when veneering frameworks made of Ce-TZP/Al₂O₃.

A Comparative Study of the RAPINA and the Virus-Neutralizing Test (RFFIT) for the Estimation of Antirabies-Neutralizing Antibody Levels in Dog Samples

The mass vaccination of dogs against rabies is a highly rational strategy for interrupting the natural transmission of urban rabies. According to the World Organization for Animal Health (OIE) and the World Health Organization (WHO), the immunization of at least 70% of the total dog population minimizes the risk of endemic rabies. Knowledge of the virus-neutralizing antibody (VNA) level against the rabies virus (RABV) is required to evaluate protective immunity and vaccine coverage of dogs in the field. The rapid focus fluorescent inhibition test (RFFIT) and the fluorescent antibody virus neutralization (FAVN) test are recommended by OIE and WHO to determine the VNA levels in serum. However, these tests are cell culture based and require the use of live viruses and specialized equipment. The rapid neutralizing antibody test (RAPINA) is a novel, immunochromatographic test that uses inactivated virus to estimate the VNA level qualitatively. It is a simple, rapid and inexpensive, although indirect, assay for the detection of VNA levels. The RAPINA has shown good positive and negative predictive values and a high concordance with the RFFIT results. In this study, we compared the performance of the two tests for evaluating the vaccination status of dogs in the Philippines, Thailand and Japan. A total of 1135 dog sera were analysed by the RAPINA and compared to the VNA levels determined by the RFFIT. The overall positive and negative predictive values of the RAPINA were 96.2-99.3% and 84.5-94.8%, respectively, with a concordance (kappa) of 0.946-0.97 among the three countries. The RAPINA results were highly homologous and reproducible among different laboratories. These results suggest that this test is appropriate to survey vaccination coverage in countries with limited resources.

Measurement of the centrality dependence of the charged-particle pseudorapidity distribution in proton-lead collisions at [Formula: see text] TeV with the ATLAS detector

The centrality dependence of the mean charged-particle multiplicity as a function of pseudorapidity is measured in approximately 1 [Formula: see text]b[Formula: see text] of proton-lead collisions at a nucleon-nucleon centre-of-mass energy of [Formula: see text] [Formula: see text] using the ATLAS detector at the Large Hadron Collider. Charged particles with absolute pseudorapidity less than 2.7 are reconstructed using the ATLAS pixel detector. The [Formula: see text] collision centrality is characterised by the total transverse energy measured in the Pb-going direction of the forward calorimeter. The charged-particle pseudorapidity distributions are found to vary strongly with centrality, with an increasing asymmetry between the proton-going and Pb-going directions as the collisions become more central. Three different estimations of the number of nucleons participating in the [Formula: see text] collision have been carried out using the Glauber model as well as two Glauber-Gribov inspired extensions to the Glauber model. Charged-particle multiplicities per participant pair are found to vary differently for these three models, highlighting the importance of including colour fluctuations in nucleon-nucleon collisions in the modelling of the initial state of [Formula: see text] collisions.

Modification of resin modified glass ionomer cement by addition of bioactive glass nanoparticles

In the present study, sol-gel derived nanoparticle calcium silicate bioactive glass was added to the resin-modified light cure glass-ionomer cement to assess the influence of additional bioactive glass nanoparticles on the mechanical and biological properties of resin-modified glass-ionomer cement. The fabricated bioactive glass nanoparticles added resin-modified glass-ionomer cements (GICs) were immersed in the phosphate buffer solution for 28 days to mimic real condition for the mechanical properties. Resin-modified GICs containing 3, 5 and 10 % bioactive glass nanoparticles improved the flexural strength compared to the resin-modified glass-ionomer cement and the samples containing 15 and 20 % bioactive glass nanoparticles before and after immersing in the phosphate buffer solution. Characterization of the samples successfully expressed the cause of the critical condition for mechanical properties. Cell study clarified that resin-modified glass-ionomer cement with high concentrations of bioactive glass nanoparticles has higher cell viability and better cell morphology compare to control groups. The results for mechanical properties and toxicity approved that the considering in selection of an optimum condition would have been a more satisfying conclusion for this study.

Spin dynamics in Na(4-x)Ir₃O₈ (x = 0.3 and 0.7) investigated by ²³Na NMR and μSR

We report (23)Na nuclear magnetic resonance (NMR) and zero-field (ZF) and longitudinal-field (LF) muon spin relaxation (μSR) measurements of the depleted hyperkagome compounds Na(4-x)Ir3O8 (x  =  0.3 and 0.7), which undergo an insulator-semimetal transition as a function of x. The (23)Na spin-lattice relaxation rates, T1(-1), follow a T(2.5) power law behavior at accessible temperatures of T  =  120-350 K. A substantial temperature dependence of T1(-1) indicates the presence of gapped excitations at elevated temperatures through the transition to a semimetallic phase. ZF-μSR results reveal that hole-doping leads to a melting of quasi-static order to a dynamically fluctuating state. The very slow muon depolarization rate which varies hardly with temperature indicates that spins are close to an itinerant limit in the largest doping x  =  0.7. The dynamic relaxation rates extracted from the LF-μSR spectra show a three-dimensional diffusive transport. Our combined NMR and μSR results suggest the occurrence of intriguing spin and charge excitations across the insulator-semimetal transition.

Comparative study between laser sintering and casting for retention of resin composite veneers to cobalt-chromium alloy

The purpose of this study was to evaluate and compare the bond strengths between resin composite veneer and laser-sintered cobalt-chromium (Co-Cr) alloy with and without retention devices (Laser-R and Laser-N respectively). Cast Co-Cr alloy with and without retention devices (Cast-R and Cast-N respectively) were also prepared for fabrication technique comparison. Disk-shaped Co-Cr alloy specimens were air-abraded with alumina and veneered with a veneering system, Estenia C&B (ES) or Ceramage (CE). After 20,000 thermocycles, tensile testing was performed. Data were analyzed by ANOVA and multiple comparison test. When no retention devices were present, no significant differences were observed between Laser-N/ES and Cast-N/ES, or between Laser- N/CE and Cast-N/CE, but ES exhibited significantly higher bond strength than CE. With retention devices, Laser-R/ES, Cast- R/ES and Laser-R/CE showed no significant differences, and their retention strengths were significantly higher than that of Cast- R/CE. Compared to cast Co-Cr alloy, laser-sintered Co-Cr alloy with retention devices provided better retention durability for resin composite-veneered prostheses.

Relationship between Cnm-positive Streptococcus mutans and cerebral microbleeds in humans

OBJECTIVE

Cerebral hemorrhage has been shown to occur in animals experimentally infected with Streptococcus mutans carrying the collagen-binding Cnm gene. However, the relationship between cerebral microbleeds and oral hygiene, with a focus on Cnm gene-positive S. mutans infection, remains unclear.

MATERIAL AND METHODS

One hundred and thirty-nine subjects participated. The presence or absence of Cnm-positive S. mutans and its collagen-binding activity were investigated using saliva samples, and relationship with cerebral microbleeds detected on MRI investigated, including clinical information and oral parameters.

RESULTS

Fifty-one subjects were identified as Cnm-positive S. mutans carriers (36.7%), with cerebral microbleeds being detected in 43 (30.9%). A significantly larger number of subjects carried Cnm-positive S. mutans in the cerebral microbleeds (+) group. S. mutans with Cnm collagen-binding ability was detected in 39 (28.1%) of all subjects, and the adjusted odds ratio for cerebral microbleeds in the Cnm-positive group was 14.4. Regarding the presence of cerebral microbleeds, no significant differences were noted in the number of remaining teeth, dental caries, or in classic arteriosclerosis risk factors.

CONCLUSIONS

The occurrence of cerebral microbleeds was higher in subjects carrying Cnm-positive S. mutans, indicating that the presence of Cnm-positive S. mutans increases cerebral microbleeds, and is an independent risk for the development of cerebrovascular disorders.

Epidemiological survey of definite cases of Meniere's disease collected by the seventeen members of the Meniere's Disease Research Committee of Japan in 1975--1976

Between Aril 1975 and December 1976, the second nationwide survey of Meniere's disease in Japan was made by the 17 members of the Meniere's Disease Research Committee of Japan. The epidemiological data from 520 patients with definite Meniere's disease were analyzed in comparison with those from the 126 patients in the non-Meniere vertiginous group (Control A) and the 228 patients in the rhinolaryngological group (Control B). The male:female ratio of definite cases of Meniere's disease was almost the same, and the age distribution peaked at the age group of 40--49 years for males, while the peak for females was at the age group of 30--39 years. 5.8% of the 520 patients had a close relative who also suffered from Meniere's disease. From the epidemiological features, it may appear that the occurrence of vertiginous attacks in Meniere's disease is influenced much more by individual than by environmental factors. However, this feature can be considered as another evidence of the psychosomatic disorders involved in Meniere's disease.

Universality class of the mott transition

Pressure dependence of the conductivity and thermoelectric power is measured through the Mott transition in the layer organic conductor EtMe_{3}P[Pd(dmit)_{2}]_{2}. The critical behavior of the thermoelectric effect provides a clear and objective determination of the Mott-Hubbard transition during the isothermal pressure sweep. Above the critical end point, the metal-insulator crossing, determined by the thermoelectric effect minimum value, is not found to coincide with the maximum of the derivative of the conductivity as a function of pressure. We show that the critical exponents of the Mott-Hubbard transition fall within the Ising universality class regardless of the dimensionality of the system.

Evaluation of glass transition temperature and dynamic mechanical properties of autopolymerized hard direct denture reline resins

This study assessed methods for evaluation of glass transition temperature (Tg) of autopolymerized hard direct denture reline resins using dynamic mechanical analysis and differential scanning calorimetry in addition to the dynamic mechanical properties. The Tg values of 3 different reline resins were determined using a dynamic viscoelastometer and differential scanning calorimeter, and rheological parameters were also determined. Although all materials exhibited higher storage modulus and loss modulus values, and a lower loss tangent at 37˚C with a higher frequency, the frequency dependence was not large. Tg values obtained by dynamic mechanical analysis were higher than those by differential scanning calorimetry and higher frequency led to higher Tg, while more stable Tg values were also obtained by that method. These results suggest that dynamic mechanical analysis is more advantageous for characterization of autopolymerized hard direct denture reline resins than differential scanning calorimetry.

Personality and suicide risk: the impact of economic crisis in Japan

BACKGROUND

The interactive effect of personal factors and social factors upon suicide risk is unclear. We conducted prospective cohort study to investigate whether the impact of the economic crisis in 1997-1998 upon suicide risk differed according to Neuroticism and Psychoticism personality traits.

METHODS

The Miyagi Cohort Study in Japan with a follow-up for 19 years from 1990 to 2008 has 29,432 subjects aged 40-64 years at baseline who completed a questionnaire about various health habits and the Japanese version of the Eysenck Personality Questionnaire - Revised Short Form in 1990.

RESULTS

The suicide mortality rate increased from 4.6 per 100,000 person-years before 1998 to 27.8 after 1998. Although both Neuroticism and Psychoticism were significantly associated with an increased risk of mortality during the whole period from 1990 to 2008, the impact of the economic crisis upon suicide risk differed between the Neuroticism and Psychoticism personality traits. Compared with the lowest category, the hazard ratios (HRs) for the highest Neuroticism increased from 0.66 before 1998 to 2.45 after 1998. On the other hand, the HRs for the highest Psychoticism decreased from 7.85 before 1998 to 2.05 after 1998.

CONCLUSIONS

The impact of the 1997-1998 economic crisis upon suicide risk differed according to personality. Suicide risk increased among these with higher Neuroticism after the economic crisis, but this was not the case for other personality subscales.

Jet energy measurement and its systematic uncertainty in proton-proton collisions at [Formula: see text] TeV with the ATLAS detector

The jet energy scale (JES) and its systematic uncertainty are determined for jets measured with the ATLAS detector using proton-proton collision data with a centre-of-mass energy of [Formula: see text] TeV corresponding to an integrated luminosity of [Formula: see text][Formula: see text]. Jets are reconstructed from energy deposits forming topological clusters of calorimeter cells using the anti-[Formula: see text] algorithm with distance parameters [Formula: see text] or [Formula: see text], and are calibrated using MC simulations. A residual JES correction is applied to account for differences between data and MC simulations. This correction and its systematic uncertainty are estimated using a combination of in situ techniques exploiting the transverse momentum balance between a jet and a reference object such as a photon or a [Formula: see text] boson, for [Formula: see text] and pseudorapidities [Formula: see text]. The effect of multiple proton-proton interactions is corrected for, and an uncertainty is evaluated using in situ techniques. The smallest JES uncertainty of less than 1 % is found in the central calorimeter region ([Formula: see text]) for jets with [Formula: see text]. For central jets at lower [Formula: see text], the uncertainty is about 3 %. A consistent JES estimate is found using measurements of the calorimeter response of single hadrons in proton-proton collisions and test-beam data, which also provide the estimate for [Formula: see text] TeV. The calibration of forward jets is derived from dijet [Formula: see text] balance measurements. The resulting uncertainty reaches its largest value of 6 % for low-[Formula: see text] jets at [Formula: see text]. Additional JES uncertainties due to specific event topologies, such as close-by jets or selections of event samples with an enhanced content of jets originating from light quarks or gluons, are also discussed. The magnitude of these uncertainties depends on the event sample used in a given physics analysis, but typically amounts to 0.5-3 %.

Joining characteristics of titanium-based orthodontic wires connected by laser and electrical welding methods

This study investigated the possibility of electrical and laser welding to connect titanium-based alloy (beta-titanium and nickel-titanium) wires and stainless-steel or cobalt-chromium alloy wires for fabrication of combination arch-wires. Four kinds of straight orthodontic rectangular wires (0.017 × 0.025 inch) were used: stainless-steel (S-S), cobalt-chromium (Co-Cr), beta-titanium alloy (β-Ti), and nickel-titanium (Ni-Ti). Homogeneous and heterogeneous end-to-end joints (15 mm long each) were made by electrical welding and laser welding. Non-welded wires (30 mm long) were also used as a control. Maximum loads at fracture (N) and elongation (%) were measured by conducting tensile test. The data (n = 10) were statistically analyzed using analysis of variance/Tukey test (P < 0.05).The S-S/S-S and Co-Cr/Co-Cr specimens showed significantly higher values of the maximum load (ML) at fracture and elongation (EL) than those of the Ni-Ti/Ni-Ti and β-Ti/β-Ti specimens for electrical welding and those of the S-S/S-S and Co-Cr/Co-Cr specimens welded by laser. On the other hand, the laser-welded Ni-Ti/Ni-Ti and β-Ti/β-Ti specimens exhibited higher values of the ML and EL compared to those of the corresponding specimens welded by electrical method. In the heterogeneously welded combinations, the electrically welded Ni-Ti/S-S, β-Ti/S-S and β-Ti/Co-Cr specimens showed significantly (P < 0.05) higher ML and EL than those of the corresponding specimens welded by laser. Electrical welding exhibited the higher values of maximum load at fracture and elongation for heterogeneously welded combinations than laser-welding.