Wall-bounded periodic snap-through and contact of a buckled sheet

Fluid flow passing a post-buckled sheet placed between two close confining walls induces periodic snap-through oscillations and contacts that can be employed for triboelectric energy harvesting. The responses of a two-dimensional sheet to a uniform flow and wall confinement in both equilibrium and post-equilibrium states are numerically investigated by varying the distance between the two ends of the sheet, gap distance between the confining walls, and flow velocity. Cases with strong interactions between the sheet and walls are of most interest for examining how contact with the walls affects the dynamics of the sheet and flow structure. At equilibrium, contact with the wall displaces the sheet to form a nadir on its front part, yielding a lower critical flow velocity for the transition to snap-through oscillations. However, reducing the gap distance between the walls below a certain threshold distinctly shifts the shape of the sheet, alters pressure distribution, and eventually leads to a notable delay in the instability. The contact between the oscillating sheet and the walls at post-equilibrium is divided into several distinct modes, changing from sliding/rolling contact to bouncing contact with increasing flow velocity. During this transition, the time-averaged contact force exerted on the sheet decreases with the flow velocity. The vortices generated at the extrema of the oscillating sheet are annihilated by direct contact with the walls and merging with the shear layers formed by the walls, resulting in a wake structure dominated by the unstable shear layers.Comment: 30 pages, 14 figures, 4 Movie

Heracleum persicum Essential Oil Nanoemulsion: A Nanocarrier System for the Delivery of Promising Anticancer and Antioxidant Bioactive Agents

Essential oils are important compounds for the prevention and/or treatment of various diseases in which solubility and bio-accessibility can be improved by nanoemulsion systems. Heracleum persicum oil nanoemulsion (HAE-NE) was prepared and biological properties were investigated against human breast cancer cells and normal human fibroblasts foreskin. Particle size, zeta potential and poly dispersity index were 153 nm, −47.9 mV and 0.35, respectively. (E)anethole (57.9%), terpinolene (13.8%), G-terpinene (8.1%), myrcene (6.8%), hexyl butyrate (5.2%), octyl bu-tanoate (4.5%) and octyl acetate (3.7%) was detected in nanoemulsion. Proliferation of cancer cells at IC50 = 2.32 \ub5g/mL was significantly (p < 0.05) inhibited, and cell migration occurred at 1.5 \ub5L/mL. The HAE-NE at 1.5, 2.5 and 3.5 \ub5g/concentration up-regulated caspase 3 and enhanced sub-G1 peak of cell cycle with nil cytotoxic effects in the liver, kidney and jejunum of mice. Villus height, villus width, crypt depth and goblet cells in mice group fed with 10 and 20 mg/kg body weight of HAE-NE improved. Cellular redox state in the liver indicated 10 and 20 mg/kg body weight of nanoemulsion significantly up-regulated the expression of SOD, CAT and GPx genes. Heracleum persicum oil na-noemulsion could be an eco-friendly nanotherapeutic option for pharmaceutical, cosmetological and food applications

Relationship between thermal properties of canola pods (without seed) with moisture content, porosity and chemical composition of pods

Thermal properties of canola pods including coefficients of thermal conductivity, thermal diffusivity and specific heat and chemical composition of rapeseed pods were measured at three levels of conventional canola varieties cultivated in the north of Iran (Hyola 50, Hyola 401 and Hyola 420) and in three times before harvest, while harvest and post-harvest. Then the relationship between the thermal properties of canola pods with chemicals, moisture and porosity were investigated. Conductivity coefficient was resulted from linear thermal method, the specific heat was obtained from mixing method and diffusion coefficients were calculated by the formula. The results showed that changes of variety and time of sampling were significant on thermal conductivity coefficient and diffusion coefficient at the probability level of 1%. Changes of variety at the level of 1% and time changes of sampling at the level of 5% were significant on specific heat. As well as the interaction between the variety and time was effective on conductivity coefficient and thermal diffusivity coefficient at 1% level. It was also observed between thermal properties and porosity, the relationship was significant at 5% level. As well as the relationship between the thermal properties and chemical composition was significant at 5% level

Quantum theory can consistently describe the use of itself in Frauchiger-Renner's Gedankenexperiment

Theoretical physics has faced many challenges since the advent of quantum mechanics. Recently, Frauchiger and Renner have presented a no-go theorem, which makes quantum mechanics more controversial. However, from our perspective, the process of proving appears questionable. Therefore, we discuss the validity of their proof approach in this letter. Here, we propose a simple thought experiment that clarifies how correctly the attributed quantum state can be written in problems similar to Frauchiger and Renner's Gedankenexperiment. In the next step, with the help of the correct form of the quantum state, it is demonstrated that a fallacy occurred in the proof of the no-go theorem, which means it cannot be valid because of the wrong proof. Ultimately, getting help from Hardy's paradox, we investigate whether there is an approach to modify their proof in order to lend the no-go theorem validity

Cyclic Fatigue Resistance of Five Different Glidepath Files in Double Curved Artificial Canals

Introduction: The aim of this study was to examine the cyclic fatigue resistances #16 ProGlider, #15.02 Scout RaCe, #15.03 NeoNiti, One G and Path-File NiTi glide path files in S-shaped artificial canals. Materials and Methods: Twenty files from each group were tested. An artificial groove simulating double (S-shaped) curved canal measuring 1.5 mm in width at the top level decreasing towards the apical reaching 0.3 mm at the tip having a 0.06 taper, 18 mm in length, and 1.5 in depth machined in a stainless steel block was used in this study. Resistance to cyclic fatigue was determined by counting the numbers of cycles to failure (NCF). Furthermore, the fragment length of the fractured tips and angle and radius of curvature formed by each file in each trajectory were evaluated. The data were analyzed using the one-way analysis of variance and Tukey’s HSD test and the level of significance was set at 5%. Results: NeoNiti GPS and Scout RaCe glide path files showed significantly higher NCF values compared to other evaluated glide path files (P<0.001) but no significant difference when compared with each other (P=0.67). Conclusion: Based on this in vitro study NeoNiti GPS and Scout RaCe glide path files had the highest cyclic fatigue resistance in simulated double (S-shaped) curved artificial canals among the evaluated path finding files. Therefore, it seems that they can be used with more confidence in endodontic treatment of S-shaped canals clinically