Seismic analysis of nailed vertical excavation using pseudo-dynamic approach

An attempt has been made to study the behavior of nailed vertical excavations in medium dense to dense cohesionless soil under seismic conditions using a pseudo-dynamic approach. The effect of several parameters such as angle of internal friction of soil （φ）, horizontal （kh） and vertical （kv） earthquake acceleration coefficients, amplification factor （fa）, length of nails （L）, angle of nail inclination （a） and vertical spacing of nails （S） on the stability of nailed vertical excavations has been explored. The limit equilibrium method along with a planar failure surface is used to derive the formulation involved with the pseudo-dynamic approach, considering axial pullout of the installed nails. A comparison of the pseudo-static and pseudo-dynamic approaches has been established in order to explore the effectiveness of the pseudo-dynamic approach over pseudo-static analysis, since most of the seismic stability studies on nailed vertical excavations are based on the latter. The results are expressed in terms of the global factor of safety （FOS）. Seismic stability, i.e., the FOS of nailed vertical excavations is found to decrease with increase in the horizontal and vertical earthquake forces. The present values of FOS are compared with those available in the literature.

Hepatic transcriptome profiling reveals early signatures associated with disease transition from non-alcoholic steatosis to steatohepatitis

Background and aim:Non-alcoholic fatty liver disease(NAFLD)is becoming a leading cause of chronic liver disease worldwide.The molecular events that influence disease progression from non-alcoholic fatty liver(NAFL)to aggressive non-alcoholic steatohepatitis(NASH)remain incompletely understood,leading to lack of mechanism-based targeted treatment options for NASH.This study aims to identify early signatures associated with disease progression from NAFL to NASH in mice and humans.Materials and methods:Male C57BL/6J mice were fed a high-fat,-cholesterol,and-fructose(HFCF)diet for up to 9 months.The extent of steatosis,inflammation,and fibrosis was evaluated in liver tissues.Total RNA sequencing(RNA-seq)was conducted to determine liver transcriptomic changes.Results:After being fed the HFCF diet,mice sequentially developed steatosis,early steatohepatitis,steatohepatitis with fibrosis,and eventually spontaneous liver tumor.Hepatic RNA-seq revealed that the key signatures during steatosis progression to early steatohepatitis were pathways related to extracel-lular matrix organization and immune responses such as T cell migration,arginine biosynthesis,C-type lectin receptor signaling,and cytokine-cytokine receptor interaction.Genes regulated by transcription factors forkhead box M1(FOXM1)and negative elongation factor complex member E(NELFE)were significantly altered during disease progression.This phenomenon was also observed in patients with NASH.

Linear and nonlinear elastic analysis of closely spaced strip foundations using Pasternak model

In this study, an attempt is made to determine the interaction effect of two closely spaced strip footings using Pasternak model. The study considers small strain problem and has been performed using linear as well as nonlinear elastic analysis to determine the interaction effect of two nearby strip footings. The hyperbolic stress-strain relationship has been considered for the nonlinear elastic analysis. The linear elastic analysis has been carried out by deriving the equations for the interference effect of the footings in the framework of Pasternak model equation; whereas, the nonlinear elastic analysis has been performed using the finite difference method to solve the second order nonlinear differential equation evolved from Pasternak model with proper boundary conditions. Results obtained from the linear and the nonlinear elastic analysis are presented in terms of non-dimensional interaction factors by varying different parameters like width of the foundation, load on the foundation and the depth of the rigid base. Results are suitably compared with the existing values in the literature.

Role of antibiotic therapy in bacterial disease：A mathematical study

Pathogenic bacteria in human system mature through the bin-synthesis of protective layer known as cell wall. This bacterial cell wall growth occurs in the presence of enzyme released by it. After maturation by the cell wall formation, pathogenic bacteria become harmful for human body as they are responsible for different diseases. Antibiotics or drugs are employed for curing bacterial diseases through the inhibition of this maturation process and it occurs by the binding progression of antibiotics with the released enzyme. But nowadays, drugs or antibiotics like β-lactum family （Amoxcillin） which are generally used for inhibition of bin-synthesis of cell wall become ineffective due to evolution of antibiotic resistance by the bacteria. Antibiotic resistance occurs when an antibiotic has lost its ability to effectively control or kill bacterial growth. As a result, the bacteria becomes ＂resistant＂ and continue to multiply for the generation of robust pathogenic bacteria in spite of drug administration. This is due to the release of another type of enzyme by the resistant bacteria which binds with the active antibiotic or drug making it ineffective. Hence, another type of drug （Clauvanic acid） is combined to resist the activity of drug hydrolyzing enzyme so that the initial drug can act effectively. Hence a combination of drug therapy is applied to cure the bacterial diseases successfully. We developed a mathematical model based on the bacterial enzyme and bacterial cell wall proliferation mechanism and showed how we can reduce the bacterial infection in the resistant cases with application of combination drugs （Amoxcillin and Clauvanic acid） to restore normal health. Based on the enzymatic activity and individual drug dynamics we studied the overall system under the single drug and combinational drug administra- tion through our formulated model analysis. We also demonstrated the different dosing time interval and dosing concentration to evaluate the optimized drug administration for arresting the cell wall formation completely. Sensitivity of the different kinetic rate constant also has been performed with subject to drug hydrolyzing enzyme. Our analytical and numerical studies also confirm the efficiency of the combinational drug treatment compared to single drug treatment being more effective in drug resistant cases providing recovery from bacterial disease.