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Continuum-based analyses for laterally loaded piles with rectangular and circular cross sections are presented using solutions that can be obtained quickly without requiring any elaborate inputs for the geometry and numerical mesh. The analysis is developed by solving the differential equations governing the displacements of the pile-soil system derived using the variational principles of mechanics. Parametric studies are performed to investigate the influence of the pile cross-sectional shape, soil layering, pile slenderness ratio, and pile-soil modulus ratio on the response of laterally loaded piles in heterogeneous soil in which the soil shear modulus varies continuously or discretely with depth. The results show that piles with the same second moment of inertia have similar lateral-load response. The lateral responses of piles in two-layer systems were mainly affected by the thickness and stiffness of the top soil layer. Soil layering also influences the lateral response of piles in three-layer soil deposits consisting of two thin layers overlying the third layer. Algebraic equations for estimating the pile-head deflection and maximum bending moment are proposed that can be readily used in design. A user-friendly spreadsheet program is developed as a tool to perform calculations of pile response using the analysis. Numerical examples demonstrating the use of the analysis are provided. [ABSTRACT FROM AUTHOR]

SUMMARY The paper presents a constitutive model for simulating the high strain-rate behavior of sands. Based on the concepts of critical-state soil mechanics, the bounding surface plasticity theory and the overstress theory of viscoplasticity, the constitutive model simulates the high strain-rate behavior of sands under uniaxial, triaxial and multi-axial loading conditions. The model parameters are determined for Ottawa and Fontainebleau sands, and the performance of the model under extreme transient loading conditions is demonstrated through simulations of split Hopkinson pressure bar tests up to a strain rate of 2000/s. The constitutive model is implemented in a finite-element analysis software Abaqus to analyze underground tunnels in sandy soil subjected to internal blast loads. Parametric studies are conducted to examine the effect of relative density and type of sand and of the depth of tunnel on the variation of stresses and deformations in the soil adjacent to the tunnels. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

SUMMARY Analytical solutions for the steady-state response of an infinite beam resting on a visco-elastic foundation and subjected to a concentrated load moving with a constant velocity are developed in this paper. The beam responses investigated are deflection, bending moment, shear force and contact pressure. The mechanical resistance of the foundation is modeled using two parameters ks and ts - ks accounts for soil resistance due to compressive strains in the soil and ts accounts for the resistance due to shear strains. Since this model represents the ground behavior more accurately than the Winkler spring model, the developed solutions produce beam responses that are closer to reality than those obtained using the existing solutions for Winkler model. The dynamic beam responses depend on the damping present in the system and on the velocity of the moving load. Based on the study, dynamic amplification curves are developed for beam deflection. Such amplification curves for deflection, bending moment, shear force and contact pressure can be developed for any beam-foundation system and can be used in design. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Separase is an endopeptidase that separates sister chromatids by cleaving cohesin Rad21 during the metaphase-to-anaphase transition. Conditional expression of Separase in tetracycline-inducible diploid FSK3 mouse mammary epithelial cells with both p53 WT and mutant (Ser-233-234) alleles of unknown physiological significance develops aneuploidy within 5 days of Separase induction in vitro. Overexpression of Separase induces premature separation of chromatids. lagging chromosomes, and anaphase bridges. In an in vivo mouse mammary transplant model, induction of Separase expression in the transplanted FSK3 cells for 3-4 weeks results in the formation of aneuploid tumors in the mammary gland. Xenograft studies combined with histological and cytogenetic analysis reveal that Separase-induced tumors are clonal in their genomic complements and have a mesenchymal phenotype suggestive of an epithelial- mesenchymal transition. Induction of Separase resulted in trisomies for chromosomes 8. 15, and 17; monosomy for chromosome 10; and amplification of the distal region of chromosomes 8 and 11. Separase protein is found to be significantly overexpressed in human breast tumors compared with matched normal tissue. These results collectively suggest that Separase is an oncogene, whose overexpression alone in mammary epithelial cells is sufficient to induce aneuploidy and tumorigenesis in a p53 mutant background. [ABSTRACT FROM AUTHOR]

Perspectives on design of offshore wind turbine (OWT) monopile foundations are provided in this paper by logically adopting optimal analysis choices with a balance between accuracy and computational efficiency. A newly developed analysis framework is used for this purpose. The analysis framework consists of dynamic analysis with linear viscoelastic soil and static analysis with nonlinear elastic soil. The framework is used to show that the Timoshenko beam theory produces most accurate monopile response although the Euler-Bernoulli beam theory produces optimal results maintaining a balance between accuracy and computational efficiency. The rigid beam theory can be used only under very restricted soil and monopile conditions. The analysis further demonstrates that static analysis is sufficient and optimal in producing monopile-soil stiffness values that can be used for determining the natural frequency of vibration of the OWTs. Moreover, nonlinear elastic analysis is sufficiently accurate and quick to produce monopile responses that can be used in design and there is no need for elasto-plastic analysis. The aspect of cyclic degradation of soil stiffness over the design life of monopiles is not considered. Thus, an optimal pathway for monopile design is described using the newly developed analysis framework and demonstrated through a design example. • A new analysis framework for offshore wind turbine monopiles is presented. • Dynamic analysis is not required for monopile design. • Euler-Bernoulli beam theory produces optimal results for monopile analysis and design. • Elasto-plastic theories are not required for monopile design. • Design calculations using the analysis framework are demonstrated. [ABSTRACT FROM AUTHOR]

A new method for dynamic analysis of Euler-Bernoulli beams resting on multi-layered viscoelastic soil is presented. The governing differential equations for beam and soil displacements are obtained using the extended Hamilton's principle, and these equations are solved using one-dimensional finite element method and analytical solutions. An iterative solution algorithm is used in conjunction with an implicit time integration scheme to obtain beam and soil responses as functions of time. The developed model resembles the traditional two-parameter spring foundation model but the analysis shows that the traditional foundation spring parameters cannot be prescribed a priori but determined as part of the solution. The model produces accurate beam response as illustrated by comparisons with equivalent two-dimensional finite element analysis. A few problems are analyzed that illustrate the novel features of the dynamic foundation model. [ABSTRACT FROM AUTHOR]

The feasibility of installation and performance of vertical ground source heat pump (GSHP) systems for heating and cooling of a typical 9000 m2 office building located in ten metropolitan cities with tropical and subtropical climates are investigated. The heating and cooling loads of the identical building in the ten cities are simulated using the EnergyPlus software. For each location, the design of the GSHP system is performed using the ground loop design (GLD) software, and the performance of the GSHP system is assessed. A multi-year cost analysis is also carried out to assess the feasibility of installation of GSHP systems from an economic point of view. It is found that GSHP systems may not be economically viable for the cities in tropical climates, particularly those near the equator, because of inefficient performance and high cooling demand. Thermal imbalance in soil caused by significantly greater cooling demand than heating demand may further exacerbate the system in tropical cities. However, the implementation of GSHP may turn into a feasible option for some of the tropical cities located near the Tropic of Cancer by adopting special design techniques or including additional hybrid energy sources. GSHP systems seem to be economically feasible and operationally efficient in the cities with subtropical climates where more balance between heating and cooling loads exist. • GSHP system considered one of the most popular geothermal system for space heating-cooling. • GSHP with special design or energy sources a good option near Tropic of Cancer. • GSHP system may not be the best option in few cities near equator. • GSHP system mostly economical in subtropical cities. [ABSTRACT FROM AUTHOR]

The dynamic behaviour of monopile supported offshore wind turbines (OWTs) is considerably influenced by inherent variabilities of soil properties and loading. This study investigates the effect of uncertainties in soil shear strength properties, and wind and wave loads on the reliability of OWT structures founded in clay. The OWT system is modeled as an Euler-Bernoulli beam and soil-structure interaction is incorporated using the American Petroleum Institute based cyclic p-y relationships. The uncertainties in soil undrained shear strength, in the parameters and equations of the p-y method, and in wind velocity are considered. Random wave loads are estimated from the code specified power spectral density function of the vertical sea surface elevation. Uncertainties in OWT responses are quantified using Monte Carlo simulations. The effects of length and diameter of the monopile, vertical sea surface displacement spectrum, and the probability distribution of wind speed on the dynamic responses of OWT are investigated. The study shows that the various power spectral density functions of wave surface displacement and various probability density functions of wind speed have a marginal effect on the response and fatigue life of OWTs. The mean fundamental frequency of the OWT system is significantly affected by the variability of the undrained shear strength of clayey soil. [ABSTRACT FROM AUTHOR]

A correction to the article "Response of Laterally Loaded Rectangular and Circular Piles in Soils With Properties Varying With Depth" by Yoon Seok Choi and colleagues, that was published in the journal in 2013 is presented.

Split Hopkinson pressure bar (SHPB) tests are performed on Himalayan phyllite rock with five different specimen sizes and with different gas gun pressures and striker bar lengths of the SHPB device. The high-strain-rate phyllite parameters investigated are the peak stress, strain at peak stress, dynamic increase factor (DIF), strain energy absorbed, and dynamic modulus. It is observed that the dimensions of the phyllite specimens and the SHPB loading characteristics (i.e., the gas gun pressure and striker bar length) have a strong impact on the phyllite response. Given that SHPB specimen dimensions are small compared to any field rock mechanics problem, the rate-dependent rock mass properties are also determined for each rock using Hoek–Brown criteria. Numerical simluations of the SHPB tests are performed using finite element (FE) analysis in conjunction with the strain rate-dependent Johnson–Holmquist (JH-2) constitutive model to calibrate the JH-2 model parameters for phyllite. The calibrated JH-2 model parameters are dependent on the phyllite specimen size and on the magnitudes of the gas gun pressure and striker bar length. The different calibrated parameters corresponding to different specimen sizes and different SHPB loading characteristics are used to perform FE analysis of a tunnel constructed in phyllite rock and subjected to a blast load. The FE results show that the tunnel responses can significantly differ with strain rate-dependent JH-2 model parameters with difference in the mean stress and vertical displacement at the crown of the tunnel in the phyllite rock as high as 126% and 250%, respectively. [ABSTRACT FROM AUTHOR]

Earthquakes threaten humanity globally in complex ways that mainly include various socioeconomic consequences of life and property losses. Resilience against seismic risks is of high importance in the modern world and needs to be sustainable. Sustainable earthquake resilience (SER) from the perspective of structural engineering means equipping the built environment with appropriate aseismic systems. Shape memory alloys (SMAs) are a class of advanced materials well suited for fulfilling the SER demand of the built environment. This article explores how this capability can be realized by the innovative SMA-based superelasticity-assisted slider (SSS), recently proposed for next-generation seismic protection of structures. The versatility of SSS is first discussed as a critical advantage for an effective SER. Alternative configurations and implementation styles of the system are presented, and other advantageous features of this high-tech isolation system (IS) are studied. Results of shaking table experiments, focused on investigating the expected usefulness of SSS for seismic protection in hospitals and conducted at the structural earthquake engineering laboratory of the University of Bonab, are then reported. SSS is compared with currently used ISs, and it is shown that SSS provides the required SER for the built environments and outperforms other ISs by benefitting from the pioneered utilization of SMAs in a novel approach. [ABSTRACT FROM AUTHOR]

Continuum-based three-dimensional (3D) elasto-plastic finite element (FE) analyses of piled raft foundations (PRFs) resting on sandy soils and subjected to uniformly distributed vertical loads are performed using the software Abaqus, and equations are developed for estimating the nonlinear soil subgrade moduli (spring stiffnesses) beneath the raft, beneath the pile base, and along the pile shaft. The unified clay and sand model (CASM) is used as the soil constitutive model in the continuum-based 3D FE analysis. Four different types of sand with three different states (loose, medium and dense) and twenty different configurations of PRFs with rectangular, square, and strip rafts are considered in this study. The developed equations of the raft and pile spring stiffnesses are subsequently used in a soil spring-based nonlinear FE analysis of PRFs performed using a structural engineering software. It is shown through verification and validation studies that the developed equations of the raft and pile spring stiffnesses can be reliably used in spring-based FE analysis of PRFs, instead of the computationally expensive continuum-based 3D FE analysis, for quick and accurate estimate of PRF responses. The developed equations of spring stiffnesses are applicable to PRFs that are similar in dimensions considered in this study. [ABSTRACT FROM AUTHOR]

Earthquakes can create severe damage to retaining structures. A numerical study is carried out to understand the seismically induced active earth pressure force on free-standing gravity retaining walls. Dynamic behavior in terms of acceleration amplification/deamplification, deformation mechanism, and earth pressure force are examined. Further, the influence of input peak ground acceleration (PGA), retaining wall height, Young's modulus of the wall, relative density of soil, and soil-structure interaction on total active earth pressure force (P ae) are investigated. The results show that P ae decreases until PGA value is around 0.55 g and later increases for higher values. The primary cause for this response is the loss of wall-soil interaction due to the overturning effect, which dominates until PGA approaches 0.55 g. Also, the generation of failure wedges causes an increase in P ae after 0.55 g. Sensitivity analysis concludes that P ae is highly sensitive to PGA, wall height, and soil-structure interaction. Based on regression analysis, an equation is proposed for the total active thrust. Later, the accuracy of the equation is confirmed by comparing it with the response of FE analysis and established study. This study contributes to developing an equation that is anticipated to provide total active thrust at the initial design stage under comparable work environment. [Display omitted] • Non-linear amplification of acceleration up to k h = 0.55 followed by deamplification. • Overturning mode of wall failure is dominant with formation of multiple failure planes in backfill. • P ae decreases with increase in k h up to 0.55 followed by increase till k h reaches 1.2 • Proposed equation for P ae considering earthquake, wall, soil, and interface characteristics. • Useful to evaluate P ae at initial design stage under similar work environment. [ABSTRACT FROM AUTHOR]

Competing Interests: Conflicts of interest None disclosed.

Background: Omipalisib has been found to affect the viability of cancer cells. However, its effect on clonogenicity - a feature of cancer stem cells, is not clear. Cells isolated from neurocutaneous melanocytosis (NCM) patients' lesions grow clonogenically. The aim of this study was to investigate the effect of omipalisib treatment on clonogenic growth of NCM cells in vitro., Materials and Methods: Clonogenic growth efficiency was evaluated by colony formation assays with or without specific growth factors. Activation of MEK and Akt was determined by immunoblots. Colony formation and cell viability were assessed upon pharmacological inhibition of MEK, Akt and mToR., Results: Clonogenicity appeared to depend on bFGF and IGF1signaling through ERK and Akt. Omipalisib treatment prevented colony formation and induced autophagic cell death., Conclusion: Signaling through Akt is important for survival of clonogenic cells in NCM, and omipalisib treatment as a monotherapy or in combination with MEK162 could be an effective therapeutic strategy to inhibit clonogenic growth., (Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Maturation of vertebrate oocytes is regulated by maturation inducing hormone (MIH), which is progesterone in all vertebrates except in fish, where it is 17alpha, 20beta dihydroxy progesterone. Once the full growth of the oocytes is achieved, they arrest at prophase of meiosis I. MIH releases oocytes from this arrest. MIH promotes the formation of a dimeric protein kinase complex known as maturation promoting factor (MPF), the regulatory component of which is cyclin B and the catalytic component is cell division cycle (Cdc2) kinase. This complex is activated by phosphorylation at Thrl61 but remains inactive due to the inhibitory phosphorylation at Thrl4 and Tyrl5. MIH stimulates Cdc25, a dual specific phosphatase, that dephosphorylates both Thrl4 and Tyrl5 and converts pre- or inactive MPF to active MPF. Germinal vesicle break down (GVBD) is the marker of oocyte maturation. In an Indian freshwater perch, Anabas testudineus, MIH induced GVBD between 18-20 h. MIH induced oocytes extract in SDS-PAGE showed over-expression of a 30 kDa protein, which is confirmed to be cyclin B by using both monoclonal and polyclonal anti-cyclin B antibodies from various sources. The size of cyclin B in other vertebrates including mammals lies between 46-55 kDa. We have cloned cyclin B gene from perch oocyte and found it to contain the domains required for its function and immunological recognition. We also cloned Cdkl gene, which is very similar to other vertebrates Cdkl. Perch oocyte Cdc25 is overexpressed prior to GVBD converting inactive MPF to active MPF that affect GVBD. The objective of this overview is to deal with the molecular regulation of MPF activation which causes final maturation of oocytes.