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This study presents the design and microstructural investigation of a single-crystal (SX) Re-bearing high-entropy superalloy (HESA-X1) featuring a thermally stable γ–γ′–γ hierarchical microstructure. The alloy exhibits FCC γ nanoparticles embedded within L12-ordered γ′ precipitates, themselves distributed in a γ matrix, with the suppression of detrimental topologically close-packed (TCP) phases. To elucidate solidification behavior and phase stability, Scheil–Gulliver and TC-PRISMA simulations were conducted alongside SEM and XRD analyses. Near-atomic scale analysis in 3D using Atom Probe Tomography (APT) revealed pronounced elemental partitioning, with Re strongly segregating to the γ matrix, while Al and Ti were preferentially enriched in the γ′ phase. Notably, Re demonstrated a unique partitioning behavior compared to conventional superalloys, facilitating the formation and stabilization of γ nanoparticles during two-step aging (Ag-2). These γ nanoparticles significantly contribute to improved mechanical properties. Long-term aging (up to 200 h) at 750–850 °C confirmed exceptional phase stability, with minimal coarsening of γ′ and retention of γ nanoparticles. The coarsening rate constant K of γ′ at 750 °C was significantly lower than that of Re-free HESA, confirming the diffusion-suppressing effect of Re. These findings highlight critical roles of Re in enhancing microstructural stability by reducing atomic mobility, enabling the development of next-generation HESAs with superior thermal and mechanical properties for high-temperature applications.

Coherent intermetallic precipitate-strengthened, Fe-Mn-based low-density steels are of interest owing to their superior mechanical properties. We present here the observation of 2-4-nm-sized, Ni-Al-type B2 precipitates localized within the disordered BCC phase, which is embedded in the major FCC structured austenitic (γ) matrix. Upon exposure to high temperatures of 1110°C for 30 min, the B2 phase coarsens, reaching a size of ~ 26 nm while still positioned within the BCC phase. It further disintegrates into ~ 6-nm-sized precipitates upon annealing at 1200°C for 30 min indicating the limited stability of the B2 phase. Thermodynamic phase analysis also supports the above observation of decreasing B2 phase stability with increasing temperature beyond 1100°C. In addition, APT also revealed the presence of κ-precipitates localized within the majority γ matrix. The collective contribution of κ, B2 and A2 phases strengthens the majority γ matrix of the hot-rolled steel, resulting in achieving an ultimate tensile strength in excess of 1.2 GPa with an extended ductility of ~34% at room temperature.

Context: The purpose of this study was to evaluate and compare the centering ability and canal transportation of TruNatomy, OneCurve, and Jizai file systems to assess their performance in oval-shaped canals using cone-beam computed tomography imaging. Materials and Methods: Forty-two fully formed single-rooted mandibular premolars were selected with a buccolingual canal size 2–2.5 times the mesiodistal size at 5 mm from the apex, with 0°–10° canal curvature with a 5–6 mm radius, at 5 mm from the apex. The teeth were divided into three groups (n = 14) and prepared with TruNatomy, OneCurve, and Jizai files based on the manufacturer's instructions. Cone-beam computed tomographic images were taken before and after instrumentation. The canal transportation and centering ability was calculated at 3, 6, and 9 mm from the apex in both mesiodistal and buccolingual directions. Statistical Analysis: Intergroup comparison was done using Kolmogorov–Smirnov test. Intragroup comparison was done using Freidman test. A comparison of categorical variables was done using the Chi-square test. Results: The results obtained did not present any statistically significant difference between the three groups, with TruNatomy and OneCurve showing relatively lesser canal transportation and better centering ratio when compared to the Jizai file system. Conclusions: It can, therefore, be concluded that all three systems used in the study are capable of safely preparing root canals with minimal errors.

Context: Sodium hypochlorite is the most widely used irrigant in endodontic practice, but it has various disadvantages. Literature has shown that herbal products such as Propolis, Azadirachta indica (AI), Triphala, Curcuma longa, and Morinda citrifolia (MC) possess good antimicrobial properties and thus can be used as potential endodontic irrigants. Aim: To evaluate and compare the antimicrobial activity of five herbal extracts, i.e., Propolis, AI, Triphala, C. longa, and MC with that of 2.5% sodium hypochlorite against Enterococcus faecalis. Materials and Methods: E. faecalis American Type Culture Collection 21292 was inoculated onto brain heart infusion agar plate. Discs impregnated with herbal medicaments were placed on the inoculated plates and incubated at 37C aerobically for 24 h and growth inhibition zones were measured. Statistical Analysis: Mean zone of inhibition in descending order was found as sodium hypochlorite > Propolis > AI > Triphala > C. longa = MC > ethanol. Statistical analysis was performed using one-way analysis of variance which showed a significant difference in the zone of inhibition of sodium hypochlorite and Propolis (P < 0.001). Results: Propolis showed highest zone of inhibition among all the herbal extracts next to sodium hypochlorite. Conclusion: Propolis and AI have significant antimicrobial activity against E. faecalis.

Combinatorial alloy design—an economical yet high-throughput alloy design approach, facilitates rapid screening of a wide range of compositions with limited material expenditure. The ever-growing demand for multi-functional modern materials’ necessitates the design of multi-component alloys that can cater to the requirements of end application, with targeted properties and ease of synthesis. To this end, we report the current trends in combinatorial alloy design approach that are available to develop a subset of multi-component alloys, namely high-entropy alloy (HEA) in both functionally tailored thin-film form and compositionally optimized bulk scale. The thin-film form synthesized by combinatorial magnetron sputtering approach enables generation of a library of compositions in a single-step process, i.e., developing multiple concentration gradients in a single reference substrate. While the identified, best performing compositions from the combinatorial library can then be scaled up to bulk form utilizing combinatorial vacuum induction melting route for application-oriented design and analysis. As an example, the bulk form of multi-component Fe 70- x Mn x Co 10 Cr 15 Cu 5 ( x  = 10, 15, 20 at.%) HEA was developed by combinatorial vacuum induction melting route to explore the influence of Mn on phase formation and compare the same with calculation of phase diagram (CALPHAD)-based theoretical predictions. The hot-rolled alloys were subjected to bulk-scale phase analysis using X-ray diffraction, microstructure imaging by scanning electron microscopy, and chemical composition analysis by energy-dispersive X-ray spectroscopy toward understanding the role of composition on the mechanical property variation in the developed alloys. Such a comprehensive approach would facilitate on the one hand rapid identification of novel, high-performance alloys, while on the other hand support the development of experimentally guided, compositionally tuned materials database for future design of multi-component alloys be it by machine learning or by conventional methods.

Introduction: To evaluate the incidence of microcrack formation canal preparation with two rotary nickel-titanium systems Mtwo and ProTaper Next along with the self-adjusting file system. Materials and Methods: One hundred and twenty mandibular premolar teeth were selected. Standardized access cavities were prepared and the canals were manually prepared up to size 20 after coronal preflaring. The teeth were divided into three experimental groups and one control group (n = 30). Group 1: The canals were prepared using Mtwo rotary files. Group 2: The canals were prepared with ProTaper Next files. Group 3: The canals were prepared with self-adjusting files. Group 4: The canals were unprepared and used as a control. The roots were sectioned horizontally 3, 6, and 9 mm from the apex and examined under a scanning electron microscope to check for the presence of microcracks. The Pearson's Chi-square test was applied. Results: The highest incidence of microcracks were associated with the ProTaper Next group, 80% (P = 0.00), followed by the Mtwo group, 70% (P = 0.000), and the least number of microcracks was noted in the self-adjusting file group, 10% (P = 0.068). No significant difference was found between the ProTaper Next and Mtwo groups (P = 0.368) while a significant difference was observed between the ProTaper Next and self-adjusting file groups (P = 0.000) as well as the Mtwo and self-adjusting file groups (P = 0.000). Conclusion: All nickel-titanium rotary instrument systems were associated with microcracks. However, the self-adjusting file system had significantly fewer microcracks when compared with the Mtwo and ProTaper Next.

Aim: The aim of this study is to compare the incidence of postoperative pain using the ProTaper Next (PTN), WaveOne Gold (WOG), and Self-Adjusting File (SAF) systems. Materials and Methods: Two hundred and fourteen patients with irreversible pulpitis were selected for single-visit endodontics. The teeth were blindly assigned to three groups based on the instrumentation system used: Group A (PTN), Group B (WOG), and Group C (SAF). Participants were asked to note the incidence of the pre- and postoperative pain on a visual analog scale at different time intervals. Paired t-test and one-way ANOVA were used along with post hoc Tukey's test. Results: The greatest mean pain in Group A (PTN) and Group B (WOG) was found to be maximum in the first 24 h with a significant reduction in pain at the subsequent observation time points of 48 h, 72 h, and 7 days. Group C (SAF) showed minimum pain followed by Group B followed by Group A which showed comparatively higher pain scores even at the end of 7 days. Conclusions: In single-visit endodontics, SAF system may prove to be a better system compared with PTN and WOG as it produces minimal postoperative pain, thus improving the overall acceptance of endodontic treatment.

We report a novel GaN/InGaN LED endowed with rectangular shaped multiple quantum wells and gradual narrowing of the bandgap of electron blocking layer (EBL) towards the anode side and subsequently analyze the obtained results through well-calibrated numerical simulation in APSYS. The results show that the droop in internal quantum efficiency (IQE) for the proposed LED decreases to 11% as compared to 54%, obtained in conventional structure. Additionally, while operated at 150 mA the proposed LED provides an output power that is enhanced by 80% more than what is obtained in conventional LED. The analysis reveals that the gradual change in Al content of EBL layer helps scale down the electric field produced in this region due to polarization which in turn imposes strong blocking on the electrons that try to escape out the active region and move to EBL layer. Moreover, due to less amount of downward valence band bending better hole injection takes place in the active region. Consequently the proposed structure allows increased electron and hole concentrations in the multiple quantum wells thereby enhancing its internal quantum efficiency while a large current flows through the device.

To assess areca nut chewing habit among middle school-aged children in Indore, India. Areca nut is chewed by itself, and in various scented preparations. It is associated with carcinogenesis, foreign body aspiration in children, and oral submucous fibrosis and may aggravate asthma. A retrospective collection of data to evaluate the prevalence of areca nut chewing among 3896 children was done. A simple random sampling was done. Children of both sexes were included in this study. 27.06% of the school-going children (1054/3896) had areca nut chewing habit. More boys chewed areca nut than girls (2:1). 45.42% of school going children of rural area pander to areca nut chewing habit, whereas in urban area 20.09% children are indulged. Government school children are more involved in areca nut chewing habit. 81.02% of the children used sweetened and flavoured form of areca nut. The majority of the users were not aware of harmful effects that the use of areca nut might be harmful for health To diminish the use of areca nut, the Indian Government should consider limiting trade, advertising, and actively communicating its health risks to the public and should deem heavy taxes on it.

In this work, we propose and investigate numerically InGaN/GaN based multiple quantum well (QW) blue light-emitting diodes (LEDs) with step quantum well (InGaN)/barrier (GaN) structures. We design four LED structures—(LED-A) InGaN/GaN rectangular quantum well, (LED-B) one down step in the middle of the QW created using sharp increase in In contents, (LED-C) one down step in the middle of the QW and the other down step in the right barrier away from QW and (LED-D) similar to LED-C barring one down step in the left barrier facing the QW. Using well-calibrated APSYS simulation program we compare the variation of output power and internal quantum efficiency of LEDs with input injection current and analyze them in the light of energy band diagram, electric field distribution, carrier concentration and radiative recombination rate. The proposed LED-D exhibits significant improvement in optical output power ~ 180.7% compared to conventional LED-A. Furthermore unlike other three LED structures, LED-D shows a very low internal quantum efficiency droop of 5.1% only at injection current of 120 mA.