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This is a unique study in which a damped porous microplate's nonlinear vibration and response are analyzed semi-analytically using MSGT and HSDT under localized loading. The substrate is modeled using the Winkler-Pasternak elastic foundation. Partial differential equations are obtained using Hamilton's principle and solved by Galerkin's method. IHB and Newmark's methods are used to trace the nonlinear vibration and response. The results show that uniform porosity leads to lower stiffness compared to symmetric porosity distribution. Pasternak foundation parameter has a larger impact on stiffness compared to Winkler parameter. The effect of geometric nonlinearity is weakened while using MSGT. [ABSTRACT FROM AUTHOR]

This article uses the semi-analytical approach to study the combined nonlinear vibration and nonlinear response of a damped porous microplate under nonuniform periodic parametric excitation to understand the complete nonlinear dynamic behavior of the plate. The plate is supported by a Winkler-Pasternak elastic foundation and modeled using modified strain gradient and third-order shear deformation theories to simulate the small-scale effects and shear deformation, respectively. Using Hamilton's principle, the governing partial differential equations of motion are derived and solved using Galerkin's method to convert them into ordinary differential equations (ODEs). These ODEs are solved using a combined incremental harmonic balance (IHB) and arc-length continuation approaches to get the nonlinear vibration (frequency–amplitude curves). The same ODEs are solved using the Newmark-β technique to obtain the nonlinear response (time–amplitude curves). The effect of elastic foundation parameters and aspect ratio on mode shape is presented. The effect of parameters such as the porosity coefficient, type of porosity, Winkler-Pasternak elastic foundation parameters, different size-dependent theories, plate thickness, size of plate, damping coefficient, different loading profiles, and loading concentrations on the nonlinear vibration and nonlinear response is examined. Also, the dependence of initial displacements on the frequency–amplitude curves with respect to the excitation frequency is demonstrated with the help of time-amplitude curves. [ABSTRACT FROM AUTHOR]

A comprehensive butter fly survey was conducted with in the Udanti Wild Life Sanctuary (UWLS), Chhattisgarh, India. A total of 76 species of butterflies were observed across 10 study sites. Lycaenidae was the most prevalent family, with 27 species, closely followed by Nymphalidae with 24 species. Hesperiidae presented 14 species, Pieridae had 6 species, Papilionidae featured 4 species from a single genus, and the Riodinidae family included a single species. Notably, two previously unreported butterfly species in Chhattisgarh have been found in the present survey: Hyarotis adrastus, Tree Flitter and Pareronia ceylanica, Dark Wanderer. These findings represent new additions to the state's butterfly fauna of Chhattisgarh. A total of 216 plant species were simultaneously documented of which 61 are known to be hosts of different butterflies. [ABSTRACT FROM AUTHOR]

Purpose: To assess the statistical fragility of randomized controlled trials that assess the use of platelet-rich plasma (PRP) for the treatment of knee osteoarthritis (OA) and report a continuous primary outcome measure with statistical significance., Methods: A systematic electronic search of MEDLINE, EMBASE, and Cochrane database was performed on August 10, 2024. All randomized controlled trials addressing the use of PRP for the treatment of symptomatic knee osteoarthritis were included that reported statistically significant primary continuous outcomes. The continuous fragility index (CFI) and continuous fragility quotient (CFQ) were calculated using approximative method, as previously described using the mean and standard deviation of the outcomes of interest., Results: There were a total of 34 eligible outcomes available for analysis. The overall median CFI across all included studies was 5.7 (IQR: 4.8-9.9). The overall median CFQ across all included studies was 0.131 (IQR: 0.055-0.243). Loss to follow-up was greater than the CFI in only 3 of 34 eligible outcomes (8.8%). The most analyzed outcome was the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) total score (n = 9) with a median CFI of 6.6 and median CFQ of 0.250. The outcome with the highest median CFI was the WOMAC stiffness subscale at 93. Spearman correlation analysis demonstrated a nonstatistically significant trend toward decreasing CFI (-0.497) and a statistically significant decrease in CFQ (-0.681; p = 0.03) with increasing grades of osteoarthritis., Conclusions: There was an overall median CFI of 5.7 and CFQ of 0.131 for RCTs that report statistically significant continuous outcomes for the use of PRP in treating symptomatic knee OA. Although there are no current guidelines regarding statistical fragility of continuous outcomes, these results can be considered fragile given statistical significance may be reversed with only a few changes in patient outcomes., Level of Evidence: II; systematic review of Level I and II studies., Competing Interests: Disclosures The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)