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A series of Zr-25Ti-xMo (x = 0, 2.5, 5, 7.5, 10 and 12.5 wt %) as-cast alloys were designed to advance a new-brand Zr-based alloy with low Young’s elastic, moderate compression strength, superior corrosion resistance and good wear behavior for the application of dental implant materials. In the present study, the microstructures of the alloys were evaluated by X-ray diffraction, scanning electron microscopy and X-ray photoelectron spectroscopy. The microhardness and uniaxial compression measurement were performed to evaluate the mechanical properties of the alloys. The electrochemical behaviors of the alloys was investigated in artificial saliva solution. The friction and wear performances of the Zr-25Ti-xMo alloys were examined by pin-on-disk under the load of 15 N. The results shows that the crystalline structure transforms from hexagonal close-pack (α phase, x = 0 wt %) to body-centered cubic structure (β phase, 5 ≤ x ≤ 12.5 wt %) through a α + β dual-phase region (x = 2.5 wt %). They exhibits excellent mechanical properties with low elastic modulus (from 17.7 to 24.4 GPa) and moderate compression strength (from 1154.4 to 1310.8 MPa). The Zr-25Ti-xMo alloys possess good corrosion resistance due to the formation of a protective passive film consisting mainly of ZrO2, TiO2 and minor MoO3. Especially, the polarization curves demonstrates that the Zr-25Ti-7.5Mo alloy has a wider passive region than the other five alloys and it possesses the lower corrosion current density and corrosion rate. Furthermore, this alloy exhibits good abrasion resistance with the lowest coefficients of friction and volume wear loss. Thus, the Zr-25Ti-7.5Mo alloy has a combination of excellent mechanical properties such as low elastic modulus, moderate yield strength and the compression strength, good electrochemical stability and well wear resistance, it is considered a promising candidate for orthopedic materials as dental implant.Bamboo culms are extensively used for structural and decorative purposes. Under certain atmospheric conditions culms can split longitudinally with detrimental effects on their appearance and structural integrity. Here we describe the first ever systematic study of this phenomenon. We tested culms of Moso bamboo (Phyllostachys Pubescens), which had been commercially dried to a moisture content of 12.5%. Using a purpose-built environmental chamber, we measured the rate of splitting for ten different test conditions, varying temperature and humidity and testing samples with and without nodes. A 50% probability of splitting after one week was found to be associated with a reduction in moisture content to 8%. We found that splitting was mainly determined by a change in relative humidity, as opposed to absolute humidity. We hypothesised that splitting occurs owing to an incompatibility in shrinkage in the tangential direction during drying, creating tensile residual stress near the outer surface of the culm. Using data from the published literature we developed a simple theoretical model capable of predicting splitting. Higher residual stress was predicted near nodes, which was consistent with our finding that splitting rarely occurs in samples having no nodes. read more These findings will be useful in the prevention of splitting, through control of the environment or other protective measures.Surface finish of NiTi is widely perceived to affect its biocompatibility and corrosion fatigue performance. The aim of this work was to find out, whether a carefully engineered surface oxide shows any beneficial effect over electropolished surface on the fatigue performance of superelastic NiTi wire mechanically cycled in simulated biofluid. Series of corrosion and environmental fatigue tensile tests was performed on superelastic NiTi wire with two different surface finishes frequently used in medical device industry. Open Circuit Potential reflecting the activity of chemical reactions on the surface of the wire cycled in electrochemical cell was continuously monitored during the fatigue tests. Microcracks at the surface of the fatigued NiTi wires were characterized by SEM and TEM. It was found that the carefully engineered 70 nm thick TiO2 oxide provides the NiTi wire with similar level of protection against the static corrosion as the less than 10 nm thin natural oxide on the electropolished wire and that it does not have any positive effect on its performance in environmental fatigue tests, whatsoever. On the contrary, the wire covered by the carefully engineered 70 nm thick TiO2 oxide displayed systematically poorer fatigue performance upon tensile cycling under specific critical loading conditions (strain amplitude less then 0.5% at large mean strains 1-7%).New strategies are necessary for the prevention of endodontic infections caused by Enterococcus faecalis, a common resistant pathogen and biofilm producer. Aim of the present study was to compare the effects of Near-Infrared (NIR) Light-Emitting Diode (LED) irradiation and different concentrations of sodium hypochlorite (NaOCl) alone or combined to each other on the E. faecalis biofilm, on artificial and human dentin surfaces. E. faecalis ATCC 29212 preformed biofilms, on polystyrene wells and on dentin discs, were treated with 880 nm NIR irradiation and NaOCl at 4%, 2.5%, 1% and 0.5% alone and combined to each other (NIR irradiation plus NaOCl 1% or 0.5%) at 5 and 10 min. Treated biofilms were compared to the controls for (i) biofilm biomass evaluation, (ii) CFU count for the quantification of cultivable cells and (iii) cells viability. All the detected experimental conditions displayed a significant reduction of biofilm biomass (p less then 0.001) and CFUs/mL (p less then 0.01) in respect to the controlLysosomes are generally thought to be required only for the late stages of phagosome maturation, providing the proton pumps (V-ATPases) and hydrolases needed to acidify and degrade the ingested prey. A recent paper by Davis et al. (EMBO J. [2020], doi10.15252/embj.2019104058) reports the involvement of lysosomes at a much earlier stage, namely in scission of phagosomes from the plasma membrane. Here we analyze these findings, highlighting a number of unexpected observations and unresolved questions.