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The article presents a study which identified STN1 knockout mouse deficiency as a risk factor for colorectal cancer (CRC) and implicated the previously unknown STN1-base excision repair (BER) axis in protecting colon tissues from oxidative damage. Topics discussed include analysis of CTC1 and STN1 genetic alterations, association between mutational signatures and STN1-deficient CRC tumors, and generation of STN1 conditional knockout (cko) mice and genotyping.

Used the Reddy's higher-order shear deformation plate theory, the nonlinear dynamic analysis and vibration of imperfect functionally graded sandwich plates in thermal environment with piezoelectric actuators (PFGM) on elastic foundations subjected to a combination of electrical, damping loadings and temperature are investigated in this article. One of the salient features of this work is the consideration of temperature on the piezoelectric layer, and the material properties of the PFGM sandwich plates are assumed to be temperature-dependent. The governing equations are established based on the stress function, the Galerkin method, and the Runge–Kutta method. In the numerical results, the effects of geometrical parameters; material properties; imperfections; elastic foundations; electrical, thermal, and damping loads on the vibration and nonlinear dynamic response of the PFGM sandwich plates are discussed. The obtained natural frequencies are verified with the known results in the literature. [ABSTRACT FROM AUTHOR]

Elliptical cylindrical shell is one of shells with special shape. Up to date, there is no publication on vibration and dynamic of functionally graded elliptical cylindrical shells. Therefore, the purpose of the present study is to investigate the nonlinear dynamic response and vibration of imperfect eccentrically stiffness functionally graded elliptical cylindrical shells on elastic foundations using both the classical shell theory (CST) and Airy stress functions method with motion equations using Volmir's assumption. The material properties are assumed to be temperature - dependent and graded in the thickness direction according to a Sigmoid power law distribution (S-FGM). The S-FGM elliptical cylindrical shell with metal-ceramic-metal layers are reinforced by outside metal stiffeners. Both the S-FGM elliptical shell and metal stiffeners are assumed to be in thermal environment and both of them are deformed under temperature simultaneously. Two cases of thermal loading (uniform temperature rise and temperature variation through thickness) are considered. The nonlinear motion equations are solved by Galerkin method and Runge-Kutta method (nonlinear dynamic response, natural frequencies). The effects of geometrical parameters, material properties, elastic foundations Winkler and Pasternak, the nonlinear dynamic analysis and nonlinear vibration of the elliptical cylindrical shells are studied. The some obtained results are validated by comparing with those in the literature. [ABSTRACT FROM AUTHOR]

In this study, a pilot-scale integrated constructed wetland with vertical flow (VF) and horizontal flow (HF) in series was designed and investigated to evaluate sewage wastewater treatment capacity. The VF unit was planted with Canna indica and was 1.2 m long, 1.2 m wide, and 1.2 m high; whereas the HF unit contained Colocasia esculenta and was 3.0 m long, 1.0 m wide, and 1.0 m high. The system was operated under different hydraulic loading rates (HLRs) of 0.1, 0.2, and 0.15 m/d. The effluent concentrations differed as HLR changed, and the means were total suspended solids (TSS): 87 mg/L; biological oxygen demand (BOD5): 31 mg/L; chemical oxygen demand (CODCr): 59 mg/L; ammonium nitrogen (NH4-N): 5.3 mg/L; nitrate nitrogen NO3-N: 8.4 mg/L; total nitrogen (TN): 7.1 mg/L; phosphate (PO4-P): 0.9 mg/L; and total coliforms (TCol): 1,485 most probable number (MPN)/100 mL. The average removal efficiencies for TSS, BOD5, TN, NH4-N, PO4-P, and TCol were 28.3, 74.9, 79, 76.2, 3.6, and 82%, respectively. There were significant differences in the effluent concentrations among the three HLRs (P < 0.05), except for PO4-P. [ABSTRACT FROM AUTHOR]

Based on Reddy's higher-order shear deformation plate theory, this article presents an analysis of the nonlinear dynamic response and vibration of imperfect functionally graded material (FGM) thick plates subjected to blast and thermal loads resting on elastic foundations. The material properties are assumed to be temperature-dependent and graded in the thickness direction according to a simple power-law distribution in terms of the volume fractions of the constituents. Numerical results for the dynamic response and vibration of the FGM plates with two cases of boundary conditions are obtained by the Galerkin method and fourth-order Runge–Kutta method. The results show the effects of geometrical parameters, material properties, imperfections, temperature increment, elastic foundations, and boundary conditions on the nonlinear dynamic response and vibration of FGM plates. [ABSTRACT FROM PUBLISHER]

This article presents analytical solutions for the nonlinear static and dynamic stability of imperfect eccentrically stiffened functionally graded material (FGM) higher order shear deformable double curved shallow shell on elastic foundations in thermal environments. It is assumed that the shell’s properties depend on temperature and change according to the power functions of the shell thickness. The shell is reinforced by the eccentrically longitudinal and transversal stiffeners made of full metal. Equilibrium, motion, and compatibility equations are derived using Reddy’s higher order shear deformation shell theory and taking into account the effects of initial geometric imperfection and the thermal stress in both the shells and stiffeners. The Galerkin method is applied to determine load–deflection and deflection–time curves. For the dynamical response, motion equations are numerically solved using Runge–Kutta method. The nonlinear dynamic critical buckling loads are found according to the criterion suggested by Budiansky–Roth. The influences of inhomogeneous parameters, dimensional parameters, stiffeners, elastic foundations, initial imperfection, and temperature increment on the nonlinear static and dynamic stability of thick FGM double curved shallow shells are discussed in detail. Results for various problems are included to verify the accuracy and efficiency of the approach. [ABSTRACT FROM AUTHOR]

The authors of this article investigate the nonlinear stability of axisymmetric functionally graded annular spherical shells with temperature-dependent material properties subjected to thermo-mechanical loads and resting on elastic foundations. Equilibrium and compatibility equations are derived by using the classical thin shell theory in terms of the shell deflection and the stress function. Approximate analytical solutions are assumed to satisfy simply supported boundary conditions and Galerkin method is applied to obtain the closed-form of load–deflection paths. An analysis is carried out to show the effects of material and geometrical properties and combination of loads on the stability of the shells. [ABSTRACT FROM PUBLISHER]

This article presents an analytical approach to investigate the nonlinear stability of thick, functionally graded material (FGM) shallow spherical shells resting on elastic foundations, subjected to uniform external pressure and exposed to thermal environments. Material properties are assumed to be temperature dependent and graded in the thickness direction according to a Sigmoid power law distribution (S-FGM) in terms of the volume fractions of constituents. Using the first-order shear deformation theory and the Galerkin method, the effects of materials, geometry, elastic foundation parameters, and temperature on the nonlinear response of the thick S-FGM shells are analyzed and discussed in detail. [ABSTRACT FROM PUBLISHER]

In this article, nonlinear vibration and dynamic response of imperfect functionally graded materials (FGM) thick double-curved shallow shells resting on elastic foundations are investigated using Reddy's third-order shear deformation shell theory in thermal environments. Material properties are assumed to be temperature dependent and graded in the thickness direction according to a simple power-law distribution in terms of the volume fractions of the constituents. The FGM shells are subjected to mechanical, damping, and thermal loads. The Galerkin method and fourth-order \hboxRunge–Kutta method are used to calculate natural frequencies, nonlinear frequency–amplitude relation, and dynamic response of the shells. In numerical results, the effects of geometrical parameters, material properties, imperfections, shear deformation, the elastic foundations, mechanical, thermal and damping loads on the nonlinear dynamic response, and nonlinear vibration of FGM double-curved shallow shells are investigated. Accuracy of the present formulation is shown by comparing the results of numerical examples with the ones available in literature. [ABSTRACT FROM AUTHOR]

This article researches nonlinear response of imperfect eccentrically stiffened symmetric FGM thin circular cylindrical shells with ceramic-metal-ceramic layers, which are symmetric through the middle surface by Sigmoid-law distribution (S-FGM) and have stiffeners surrounded on elastic foundations under uniform radial load. The Donnell classical shell theory, stress function, and Galerkin method are used for investigation of the nonlinear stability of the S-FGM shell. The obtained results show the effects of the stiffeners, elastic foundations, mechanical load, and material parameters on the nonlinear buckling response of symmetric S-FGM circular cylindrical shells. [ABSTRACT FROM AUTHOR]

This paper presents an analytical approach to investigate the nonlinear dynamic response and vibration of thick functionally graded material (FGM) plates using both of the first-order shear deformation plate theory and stress function with full motion equations (not using Volmir's assumptions). The FGM plate is assumed to rest on elastic foundation and subjected to mechanical, thermal, and damping loads. Numerical results for dynamic response of the FGM plate are obtained by Runge-Kutta method. The results show the material properties, the elastic foundations, mechanical and thermal loads on the nonlinear dynamic response of functionally graded plates. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents an analytical approach to investigate the nonlinear dynamic response and vibration of imperfect eccentrically stiffened FGM thick double curved shallow shells on elastic foundation using both the first order shear deformation theory and stress function with full motion equations (not using Volmir's assumptions). The FGM shells are assumed to rest on elastic foundation and subjected to mechanical and damping loads. Numerical results for dynamic response of the FGM shells are obtained by Runge–Kutta method. The results show the influences of geometrical parameters, the material properties, imperfections, the elastic foundations, eccentrically stiffeners and mechanical loads on the nonlinear dynamic response and nonlinear vibration of functionally graded double curved shallow shells. The numerical results in this paper are compared with results reported in other publications. [Copyright &y& Elsevier]

Abstract: This paper first time presents an analytical investigation on the nonlinear postbuckling of imperfect eccentrically stiffened thin FGM plates under temperature and resting on elastic foundation using a simple power-law distribution (P-FGM). Both of the FGM plate and stiffeners are deformed under thermal loads. The formulations are based on the classical plate theory taking into account geometrical nonlinearity, initial geometrical imperfection, temperature-dependent properties and the Lekhnitsky smeared stiffeners technique with Pasternak type elastic foundation. By applying Galerkin method and using stress function, effects of material and geometrical properties, temperature, elastic foundation and eccentrically stiffeners on the buckling and postbuckling loading capacity of the eccentrically stiffened FGM plate in thermal environments are analyzed and discussed. Some results were compared with the one of the other authors. [Copyright &y& Elsevier]

Abstract: This paper presents an analytical approach to investigate nonlinear response of functionally graded cylindrical panels under uniform lateral pressure with temperature effects are incorporated. Material properties are assumed to be temperature-independent, and graded in the thickness direction according to a simple power law distribution in terms of the volume fractions of constituents. Equilibrium and compatibility equations for cylindrical panels are derived by using the classical shell theory with both geometrical nonlinearity in von Karman–Donnell sense and initial geometrical imperfection are taken into consideration. The resulting equations are solved by Galerkin method to determine explicit expressions of nonlinear load-deflection curves. Stability analysis for a simply supported panel shows the effects of material and geometric parameters, in-plane restraint and temperature conditions, and imperfection on the nonlinear response of the panel. [Copyright &y& Elsevier]

This study proposes a novel blade configuration, made with a multicurve profile, to further maximize the advanced benefits and the performance of a Savonius turbine for energy harvesting applications. The advantages of the presently designed blade are proved by a detailed analysis of the flow mechanism and the performance through a sequence of two-dimensional (2D) unsteady computational fluid dynamics simulation. The remarkable finding states that the main blade section with a length ratio of 0.9 combined with an elliptical auxiliary section effectively enhances the positive wind flow phenomena around the blade, especially for the returning position, which either smooths the flow or reduces the pressure on the blade's convex side. As a result, greater torque is obtained by the present configuration, responding to the improvement of the power generation to 0.24 – about 5.5% at the low TSR = 0.8 and up to 0.28 - about 185% at the high TSR = 1.5 over the conventional configurations. The effectiveness of the presently designed blade is further proved with more than 20% improvement in self-staring speed through six degrees of freedom analysis. The results above state a high potential application of the turbine with the presently designed blade for renewable energy applications and for supporting vulnerable communities without access to electricity. [ABSTRACT FROM AUTHOR]

This paper researches the thermal stability of eccentrically stiffened plates made of functionally graded materials (FGM) with metal–ceramic–metal layers subjected to thermal load. The equilibrium and compatibility equations for the plates are derived by using the first-order shear deformation theory of plates, taking into account both the geometrical nonlinearity in the von Karman sense and initial geometrical imperfections with Pasternak type elastic foundations. By applying Galerkin method and using stress function, effects of material and geometrical properties, elastic foundations, temperature-dependent material properties, and stiffeners on the thermal stability of the eccentrically stiffened S-FGM plates in thermal environment are analyzed and discussed. [ABSTRACT FROM PUBLISHER]

The nonlinear dynamics of an eccentrically stiffened functionally graded material (ES-FGM) plates resting on the elastic Pasternak foundations subjected to mechanical and thermal loads is considered in this article. The plates are reinforced by outside stiffeners with temperature-dependent material properties in two cases: uniform temperature rise and through the thickness temperature gradient. Both stiffeners and plate are deformed under temperature. Using Reddy’s third-order shear deformation plate theory, stress function, Galerkin and fourth-order Runge–Kutta methods, the effects of material and geometrical properties, temperature-dependent material properties, elastic foundations, and stiffeners on the nonlinear dynamic response of the ES-FGM plate in thermal environments are studied and discussed. Some obtained results are validated by comparing with those in the literature. [ABSTRACT FROM PUBLISHER]

Abstract: This paper presents a method to determine bending deflection of three-phase polymer composite plates consisting of reinforced glass fibers and titanium oxide (TiO2) particles. This method analyzes bending with taking into account two important effects which are interaction between titanium oxide particles and polymer matrix and shear deformation. Mechanical properties of the three-phase composite plates are clearly related to mechanical properties and volume fractions of constituent materials. These explicit expressions play an important role in design of composite materials as well as optimal behavior of three-phase composite plates. [ABSTRACT FROM AUTHOR]

Because structures made of FG material often operate in high temperature environments, it is critical to understand the mechanical behavior of these structures while taking temperature into consideration. As a result, the phase-field model is employed in this work to investigate the thermal buckling of fractured functionally graded material (FGM) plates. Additionally, this study demonstrates the difference between the plate's static stability response to thermal load in the case of temperature-dependent (TD) material mechanical properties and in the case of temperature-independent (TID) material mechanical properties, illustrating that the calculation for these two cases will appear to be highly skewed. This provides a scientifically valid foundation for scientists to adopt a more realistic computation model. The equations are based on the third-order shear deformation plate theory (TSDT) of Reddy. This work proves that this discrepancy strongly depends on the material, boundary condition, crack length as well as thickness of the crack plate, it has never been explored in published work, the results give very useful and needful information for scientists to choose the best accuracy case to calculate and apply in practice. [ABSTRACT FROM AUTHOR]

• Nonlinear vibration analysis of auxetic laminated plate is presented. • The laminated plate is subjected to blast, thermal, electric and magnetic loadings. • The mechanical properties of auxetic core depend on the geometrical parameters of the unit cells. • The basic equations are derived based on the Reddy's higher order shear deformation plate theory. • The numerical results are obtained by using Galerkin and fourth-order Runge–Kutta methods. Mathematic modeling and analytical approach are presented for nonlinear vibration analysis of laminated plate with auxetic honeycomb core and magneto-electro-elastic face sheets supported by Pasternak-type elastic foundations. The laminated plate is subjected to the simultaneous action of blast, thermal, electric and magnetic loadings. The mechanical properties of auxetic core including negative Poisson's ratio are assumed to depend on the geometrical parameters of the unit cells and elastic modulus of original material. The volume fraction of two components of each magneto-electro-elastic face sheet is chosen equally. The nonlinear motion equations and the geometrical compatibility equation are established by using Reddy's higher order shear deformation plate theory taking into account the coupling between elastic, electric and magnetic fields. The analytical vibration solutions for the auxetic laminated plate can be obtained by using Galerkin and fourth-order Runge – Kutta methods. The numerical results are conducted to investigate the effect of geometrical and material parameters, elastic foundations, temperature increment, magnetic and electric potentials on the vibration characteristics of the auxetic laminated plate. [ABSTRACT FROM AUTHOR]

Based on Reddy's first-order shear deformation theory, the nonlinear dynamic response and vibration of imperfect functionally graded carbon nanotube-reinforced composite (FG CNTRC) circular cylindrical shells subjected to an external dynamic load uniformly distributed on the surface of the shell and axial compression in thermal environment are presented. The circular cylindrical shells are surrounded on elastic foundations and reinforced by single-walled carbon nanotubes which vary according to the linear functions of the shell thickness. The shell's effective material properties are assumed to depend on temperature and estimated through the rule of mixture. By applying the stress function, Galerkin method and fourth-order Runge–Kutta method, nonlinear dynamic response and natural frequencies for imperfect FG CNTRC circular cylindrical shells are determined. In numerical results, the influences of geometrical parameters, elastic foundations, initial imperfection, temperature increment, dynamic loads and nanotube volume fraction on the nonlinear vibration of FG CNTRC circular cylindrical shells are investigated. The obtained results are validated by comparing with those of other authors. [ABSTRACT FROM AUTHOR]

Based on a complete mathematical model, the authors set up a problem of metal plate destruction by contacting explosive charge in highly nonlinear dynamic software AUTODYN and solved in two cases using the Johnson–Cook and von Mises strength models. The numerical simulation results were compared with the experimental results and showed a good fit of numerical calculations versus experiments by using the von Mises strength model. The study also shows that the Johnson–Cook strength model, if applied unreasonably, will lead to large errors, which would help to avoid mistakes in the future high speed impact study. [ABSTRACT FROM AUTHOR]

The study deals with the formulation of governing equations of eccentrically stiffened functionally graded materials annular spherical shells resting on elastic foundations and based upon the classical shell theory and the smeared stiffeners technique taking into account geometrical nonlinearity in Von Karman-Donnell sense. The annular spherical shells are reinforced by eccentrically longitudinal and transversal stiffeners made of full metal or full ceramic depending on situation of stiffeners at metal-rich side or ceramic-rich side of the shell respectively. Approximate solutions are assumed to satisfy the simply supported boundary condition and Galerkin method is applied to obtain closed-form relations of bifurcation type of buckling loads. Numerical results are given to evaluate effects of inhomogeneous, dimensional parameters, outside stiffeners and elastic foundations to the buckling of structures. [ABSTRACT FROM PUBLISHER]

• This study is the first attempt to assess the response of regional offshore wind energy potential to the global warming effect over a tropical sea of Vietnam until the end of the 21st century. • This study revealed a decreasing trend of the annual mean wind speed and power potential over the sea of Vietnam, which is consistent for two greenhouse-gases Representative Concentration Pathway (RCP) scenarios 8.5 and 4.5. However, the change in the seasonal mean is asymmetric, i.e., both increase/decrease trends exist. • The turbine-based assessment showed that the cumulative annual energy obtained from the 12 MW and 8 MW turbines could reach the highest about 50.9 GWh and 30.7 GWh (2080–2099 average under scenario RCP8.5) but the difference in their capacity factor is much smaller suggesting that turbine 8 MW should be considered in the sense of cost-effectiveness in some areas. Understanding the future offshore wind energy is crucial for making an appropriate energy strategy. Yet how offshore wind energy will respond to the rapidly intensifying global warming remains inconclusive. Focusing on a tropical sea in Vietnam, this study assesses the climatic impact of global warming on the local offshore wind potential. Dynamically downscaled wind data obtained by an edge-cutting fine-resolution regional climate model with two greenhouse-gases Representative Concentration Pathway (RCP) scenarios 8.5 and 4.5 were biased-corrected with a quantile mapping method before using for assessment. Results revealed a changing trend of the annual-mean offshore wind speed and power potential in Vietnam under both scenarios. However, the change is seasonally asymmetric with decreases of about 2 – 10% in September-October-November and slight increases of about 2 – 4% in December-January-February. The turbine-based assessment showed that the cumulative annual energy obtained from the 12 MW and 8 MW turbines could reach the highest about 50.9 GWh and 30.7 GWh (2080–2099 average under scenario RCP8.5) but the difference in their capacity factor is much smaller, suggesting that turbine 8 MW should be considered in the sense of cost-effectiveness in some areas. [ABSTRACT FROM AUTHOR]

The article discusses research on the crystallization and X-ray crystallographic analysis of XometB or the cystathionine γ-synthase (CGS) derived from Xanthomonas oryzae pv. oryzae (Xoo). Topics explored include the use of polymerase chain reaction in the amplification of the XometB gene, the preparation of the XometB stock solution for crystallization trials, and the enzymatic mechanism data gathered which may be utilized in the development of an antibacterial drug against Xoo.

Conjugated polymers are promising materials for various cutting-edge technologies, especially for organic conducting materials and in the energy field. In this work, we have synthesized a new conjugated polymer and investigated the effect of distance between bond layers, side-chain functional groups (H, Br, OH, OCH3 and OC2H5) on structural characteristics, phase transition temperature (T), and electrical structure of C13H8OS using Density Functional Theory (DFT). The structural characteristics were determined by the shape, network constant (a, b and c), bond length (C–C, C–H, C–O, C–S, C–Br and O–H), phase transition temperatures, and the total energy (Etot) on a base cell. Our finding shows that the increase of layer thickness (h) of C13H8OS–H has a negligible effect on the transition temperature, while the energy bandgap (Eg) increases from 1.646 eV to 1.675 eV. The calculation of bond length with different side chain groups was carried out for which C13H8OS–H has C–H = 1.09 Å; C13H8OS–Br has C–Br = 1.93 Å; C13H8OS–OH has C–O = 1.36 Å, O–H = 0.78 Å; C13H8OS–OCH3 has C–O = 1.44 Å, O–H =1.10 Å; C13H8OS–OC2H5 has C–O = 1.45 Å, C–C = 1.51Å, C–H = 1.10 Å. The transition temperature (T) for C13H8OS–H was 500 K < T < 562 K; C13H8OS–Br was 442 K < T < 512 K; C13H8OS–OH was 487 K < T < 543 K; C13H8OS–OCH3 was 492 K < T < 558 K; and C13H8OS–OC2H5 was 492 K < T < 572 K. The energy bandgap (Eg) of Br is of Eg = 1.621 eV, the doping of side chain groups H, OH, OCH3, and OC2H5, leads to an increase of Eg from 1.621 eV to 1.646, 1.697, 1.920, and 2.04 eV, respectively. [ABSTRACT FROM AUTHOR]