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This paper reviews the advancements in wall-climbing robots, focusing on optimizing adsorption and introducing novel suction techniques. Wall-climbing robots have garnered significant attention due to their potential in hazardous operations and their ability to navigate various wall surfaces without compromising mobility. One such innovation includes a robot designed for smooth wall surfaces, integrating a vacuum adsorption system and adhesion belts. This design enhances the robot’s flexibility and steerability, with an in-depth analysis of its attachment mechanism for climbing tasks. Key parameters such as the required adsorption force and motor torque for stable climbing have been derived, with the robot’s prototype demonstrating high stability and adaptability across different wall surfaces. Another pivotal study delves into the modelling and experimental analysis of suction pressure in the suction chamber, emphasizing the role of different chamber contours. A novel addition of a bottom restrictor at the chamber’s base has been introduced, with its design and performance analysed using 3D modelling and computational fluid dynamics. The restrictor’s impact on the robot’s adhesion efficiency has been experimentally assessed, showcasing promising results on non-plastered brick walls. Through these studies, the paper underscores the continuous evolution and potential of wall-climbing robots in diverse applications.

Objectives Leptin (LEP) is a vital placental hormone that is known to affect different aspects of placental function and fetal development. The present study aimed to determine the association of placental LEP transcript abundance with maternal, placental, and newborn parameters. Subjects/methods In this retrospective case-control study, placental samples (n = 105) were collected from small (SGA) and appropriate (AGA) for gestational age full-term singleton pregnancies (n = 44 SGA and n = 61 AGA). Placental transcript abundance of LEP was assessed by real-time quantitative PCR after normalization to a reference gene panel. LEP methylation was measured using a quantitative MethyLight assay in a subset of samples (n = 54). Results Placental LEP transcript abundance was negatively and significantly associated with placental weight ([beta] = -3.883, P = 0.015). This association continued to be significant in the SGA group ([beta] = -10.332, P = 0.001), both in female ([beta] = -15.423, P = 0.021) and male births ([beta] = -10.029, P = 0.007). LEP transcript abundance was not associated with LEP methylation levels (Spearman's [rho] = 0.148, P = 0.287). Conclusion We conclude that placental upregulation of LEP is an integral and fetal sex-independent component of placental growth restriction, which can be potentially targeted through maternal dietary modifications to improve fetoplacental growth., Author(s): P. Kochhar [sup.1] , C. Manikandan [sup.1] [sup.5] , G. Ravikumar [sup.2] , P. Dwarkanath [sup.1] , C. N. Sheela [sup.3] , S. George [sup.3] , A. Thomas [sup.3] [...]

Machining hard materials with 45–48 HRC is difficult in turning operation because of the improvident cutting parameter selections for the operation. The OHNS (AISI/SAE-01–48HRC) steel is mainly preferred for the production of shafts, gears, cams, and press tools. The OHNS material was turned at a dry state using VP-coated carbide inserts. The seventeen experimental trials were designed by central composite design (CCD) with different levels of cutting parameters, like feed rate, cutting speed, and depth of cut. Design Expert-11 software desirability approach and TOPSIS (Technique for Order Preference by Simulating the Ideal Solution) were used to analyse the experimental results to obtain a single optimal solution that defines better results on metal removal rate (MRR) and surface finish (Ra). RSM solution with 81.3% desirability, the cutting speed of 60 m/min, feed rate of 0.08 mm/rev, and depth of cut 1 mm as the optimal cutting parameters; similarly, TOPSIS algorithm calculation identifies the cutting parameter combinations, such as 40 m/min cutting speed, 0.09 mm/rev feed rate, and 1 mm depth cut to enrich the quality of the machined steel; however, the desirability approach cutting parameter setting is better for the surface finish achievement, while TOPSIS solution is better to obtain significant MRR. The confirmation test results validated for the predicted values of both approaches; as such, the experimental results were maintained better convenience than the predicted one. For the optimum cutting parameter combinations, an MRR of 22.032 gm/min and surface roughness of 0.781 μm were obtained at 60 m/min cutting speed, 0.08 mm/rev feed rate, and 1 mm depth of cut. [ABSTRACT FROM AUTHOR]

0.42Pb(Mg0.335Nb0.665)O3–0.26Pb(In0.5Nb0.5)O3–0.32PbTiO3 (PMINT): x % Eu2O3 (x = 0, 1, 1.5, 2 and 2.5) ternary ceramics were prepared using solid-state reaction technique. The powder X-ray diffraction analysis confirmed the diffusion of Eu3+ ions in the PMINT lattice and tetragonal structure in the P4mm space group. The temperature and frequency dependence of dielectric measurement revealed the relaxor such as behaviour and high Curie temperature (Tc ~ 180 °C) achieved for PMINT: 1% Eu ceramic. High remnant polarization (Pr ~ 28.09 µC/cm2) and coercive field (Ec ~ 13.36 kV/cm) were attained for PMINT: 1% Eu and PMINT: 2% Eu samples, respectively. An improved piezoelectric charge coefficient d33 ~ 462 pC/N was found for PMINT: 1.5% Eu. The unipolar strain vs electric field (S–E) hysteresis loops were investigated and the maximum strain Smax = 0.11% for PMINT: 2.5% Eu and the piezoelectric strain coefficient d33* = 387 pm/V for PMINT: 1.5% Eu. This work provides a new way to fabricate Eu-doped PMINT ternary ceramics, both piezoelectric and induced strain properties can be enhanced simultaneously. [ABSTRACT FROM AUTHOR]