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This paper presents an analytical approach for buckling and postbuckling analysis for functionally graded graphene‐reinforced composite (FG‐GRC) toroidal shell segments with the trapezoidal or round corrugated core under the axial tension and compression. The considered shells are placed in a thermal environment and surrounded by an elastic foundation. Based on the von Kármán‐Donnell shell theory with geometrical nonlinearities, Stein and McElman approximation, and a homogenization technique for corrugated shells, the basic equations of shells are established. The previous homogenization technique is improved by adding the thermal forces in the internal force expressions. The shell‐foundation interaction is expressed using the model of the Pasternak assumption. The Ritz energy method is used to obtain the pre‐buckling and postbuckling behaviors of the shells, from which the critical buckling tensions and compressions can be investigated. The influences of FG‐GRC face sheets, corrugated core, and foundation on the buckling behavior of sandwich shells can be shown in the numerical analysis. Highlights: Postbuckling of toroidal shell segments with the corrugated core is analyzed.A homogenization technique is improved for the thermal forces in the core.The shells are made of functionally graded graphene‐reinforced composite.The nonlinear Kármán‐Donnell shell theory and Ritz energy method are applied.Special effects of input parameters on the buckling behavior are investigated. [ABSTRACT FROM AUTHOR]

This paper presents a new semi-analytical approach for the nonlinear vibration and dynamic responses of functionally graded graphene platelet-reinforced composite (FG-GPLRC) panels with complex curvature reinforced by orthogonal and/or inclined stiffeners in the thermal environment resting on the nonlinear viscoelastic foundation with the nonlinearities of von Kármán in the framework of the higher-order shear deformation theory (HSDT). The three curvature types of complexly curved panels are considered to be cylindrical, sinusoid, and parabola panels. Orthogonal and/or inclined stiffeners are modeled utilizing an improved smeared stiffener technique. The stress function form is estimated by applying the like-Galerkin method for complexly curved panels. By applying the Lagrange function and Euler–Lagrange equation, the nonlinear equations of motion of the panels are obtained. The viscous damping effects of the viscoelastic foundation are considered by utilizing the Rayleigh dissipation function. Numerical results are examined utilizing the Runge–Kutta method to acquire the time-deflection curves, and by utilizing the Budiansky–Roth criterion, the critical dynamic buckling loads are determined. From the investigated results, it is possible to evaluate the nonlinear vibration and buckling dynamic responses of three forms of panels with stiffeners. [ABSTRACT FROM AUTHOR]

An analytical approach for nonlinear buckling and postbuckling responses of corrugated-core toroidal shell segments with carbon nanotube (CNT) reinforced face sheets in thermal environment subjected to radial pressure is reported in this work. Three distribution laws of functionally graded CNT-reinforced layers and the trapezoidal and round forms of the corrugated core are investigated. An equivalent technique for corrugated panels is improved by adding thermal forces to model the behavior of the corrugated core. The nonlinear equations are formulated by using the geometrically nonlinear Donnell shell theory considering Pasternak's foundation. An algorithm to solve a system of nonlinear equations is established using the Ritz energy method with three shell deflection amplitudes. The postbuckling expressions between the compressive and tensile loads with maximal deflection and the critical compressive and tensile loads are determined. The numerically investigated examples present the significantly beneficial effects of corrugated core and functionally graded CNT-reinforced face sheets on nonlinear buckling responses of structures. [ABSTRACT FROM AUTHOR]

The nonlinear vibration and dynamic responses of functionally graded graphene‐reinforced composite (FG‐GRC) laminated cylindrical, parabolic, and sinusoid panels stiffened by FG‐GRC stiffeners in the uniformly distributed temperature variation are presented in this paper. An improved smeared stiffener technique is used to model the added stiffnesses of stiffeners to the total stiffnesses of panels. The higher‐order shear deformation shell theory (HSDT) with the geometrical nonlinearities of von Kármán is applied to establish the governing formulations. The stress function form is estimated using the approximated technique for complex curvature panels. Lagrange function and Euler‐Lagrange equations are applied, and the Rayleigh dissipation function is taken into account to obtain the nonlinear equation of motion. Numerical examples are investigated using the Runge‐Kutta method to obtain the dynamic responses of panels, and the critical dynamic buckling loads of panels are considered using the Budiansky‐Roth criterion. Some significant remarks on the nonlinear vibration and dynamic buckling responses of three types of stiffened panels can be recognized from the numerical examples. [ABSTRACT FROM AUTHOR]

Patients diagnosed with soft tissue sarcoma (STS) often present at intermediate to advanced stages, with inherently limited therapeutic options available. There is an urgent need to identify novel therapeutic targets. In this study, by screening STS data from the Cancer Genome Atlas (TCGA) and Genotype Tissue Expression (GTEx) databases, KIFC1 is identified as a potential biomarker and a promising therapeutic target for STS. Notably, a significant increase in KIFC1 levels, which exhibited a strong correlation with a poor prognosis in STS patients is observed. The findings revealed that knockout of KIFC1 suppressed STS growth both in vitro and in vivo. Furthermore, KIFC1 is found to regulate cellular senescence in STS, which has not been reported before. that targeting KIFC1 induced cellular senescence via interacting with FXR1, an RNA-binding protein is discovered, thereby further stabilizing MAD2L1 mRNA in an m6A-dependent manner. Additionally, the suppression of KIFC1 markedly diminished the growth of patient-derived xenografts (PDX) and triggered senescence. This study provides the first evidence that KIFC1 inhibition induces cellular senescence through MAD2L1, underscoring KIFC1 as a novel prognostic biomarker and a potential therapeutic target for STS., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Background: Blueberries are ornamental plants grown in pots in many yards in the Mekong Delta (MD) region. In this region, the recent alluvial (RA) soil is fertile and ancient alluvial (AA) soil is considered degraded because it only has around a quarter of the nutrient content of the RA soil. Both soils have a high clay content, so organic matter is needed to improve their physical condition. This study aimed to identify the nutrients that limit the yield of blueberries in RA and AA soils of the MD., Methods: The pot experiment was performed using a factorial randomized block design (RBD) with two factors: (a) two soil types (RA and AA) and (b) four omission or treatment conditions (NPK, PK, NK, and NP). The same fertilizer formula was used for all treatments, including 45N-20P 2 O 5 -20K 2 O and mixing CHC (10 tha -1 ) into the potting soil., Results: The blueberry yield in AA soil was only 81% of that in RA soil. In both RA and AA soils, N omission caused foliar N content deficiency (10.42 g kg -1 ), resulting in the content of foliar P (0.84 g kg -1 ) and K (3.78 g kg -1 ) to fall below the Trevett threshold. In both RA and AA, N omission resulted in reduced fruit yield (47% and 39%, respectively) as well as reduced weight of the stem (70% and 42%, respectively) and leaf (59% and 46%, respectively). Increased crop yields in soils were mainly related to nitrogen fertilizer. The indigenous nutrient supply (INS) of RA, which is fertile, was high but its apparent nutrient recovery efficiency (ARE) index was low, whereas the INS of AA, or the level of degraded soil, was low but its ARE index was high. In alluvial soils, the higher the INS level, the less positive the impact on the ARE index. In AA soil, the indigenous N and K supplies can be improved through fertilizer investment; however, a balance must be achieved considering economic efficiency., Competing Interests: The authors declare there are no competing interests., (©2024 Ngoc et al.)