8 research outputs found
Stress–Strain Model for Freezing Silty Clay under Frost Heave Based on Modified Takashi’s Equation
In analyzing frost heave, researchers often simplify the compressive modulus of freezing soil by considering it as a constant or only as a function of temperature. However, it is a critical parameter characterizing the stress–strain behavior of soil and a variable that is influenced by many other parameters. Hence, herein several one-dimensional freezing experiments are conducted on silty clay in an open system subjected to multistage freezing by considering the compressive modulus as a variable. First, freezing soil under multistage freezing is divided into several layers according to the frozen fringe theory. Then, the correlation between the freezing rate and temperature gradient within each freezing soil layer is investigated. Takashi’s equation for frost heave analysis is modified to extend its application conditions by replacing its freezing rate term with a temperature gradient term. A mechanical model for the stress–strain behavior of freezing soil under the action of frost heave is derived within the theoretical framework of nonlinear elasticity, in which a method for determining the compressive modulus of freezing soil with temperature gradient, overburden pressure, and cooling temperature variables is proposed. This study further enhances our understanding of the typical mechanical behavior of saturated freezing silty clay under frost heave action
Evaluating the Mode of Antifungal Action of Heat-Stable Antifungal Factor (HSAF) in Neurospora crassa
Heat-stable antifungal factor (HSAF) isolated from Lysobacter enzymogenes has shown a broad-spectrum of antifungal activities. However, little is known about its mode of action. In this study, we used the model filamentous fungus Neurospora crassa to investigate the antifungal mechanism of HSAF. We first used HSAF to treat the N. crassa strain at different time points. Spore germination, growth phenotype and differential gene expression analysis were conducted by utilizing global transcriptional profiling combined with genetic and physiological analyses. Our data showed that HSAF could significantly inhibit the germination and aerial hyphae growth of N. crassa. RNA-seq analysis showed that a group of genes, associated with cell wall formation and remodeling, were highly activated. Screening of N. crassa gene deletion mutants combined with scanning electron microscopic observation revealed that three fungal cell wall integrity-related genes played an important role in the interaction between N. crassa and L. enzymogens. In addition, Weighted Gene Co-Expression Network Analysis (WGCNA), accompanied by confocal microscopy observation revealed that HSAF could trigger autophagy-mediated degradation and eventually result in cell death in N. crassa. The findings of this work provided new insights into the interactions between the predatory Lysobacter and its fungal prey
Review on HVDC cable terminations
With modern power utilities going green by utilising renewable energy technologies and the development of the smart power grid, high-voltage direct current (HVDC) technologies become more and more important in the energy transmission. In particular, HVDC cable systems play a prominent role in undersea power transmission and offshore renewable energy integration. As an essential part of a complete HVDC cable system, the cable termination is one of the most critical components. The mathematical and physical background of HVDC cable systems is discussed and the development of various types of HVDC cable terminations is reviewed. Regarding the non-uniform field distribution, the influence of temperature on the non-linear conductivity is briefly discussed. Furthermore, faults of terminations caused by inappropriate installation and testing of cable systems are discussed
A novel organ preservation solution with efficient clearance of red blood cells improves kidney transplantation in a canine model
Abstract Organ preservation solutions are designed to minimize organ damage during transplantation. A novel preservation solution, WMO-II, was developed to have a low viscosity and to improve microvasculature perfusion for kidneys. In an autologous canine transplantation model, kidney function and recovery were evaluated after organs were flushed and cold-stored with WMO-II or HTK solution, a perfusate currently approved for clinical use. The average number of red blood cells remaining in a single glomerulus after flushing with WMO-II was significantly reduced when compared with HTK solution. Additionally, WMO-II reduced the number of apoptotic bodies in stored kidneys compared to HTK treated tissue after 48Â h of cold storage by reducing expression of Caspase-9, BiP, Chop, and Caspase-12. WMO-II solution reduced serum creatinine levels and serum potassium in kidneys stored for 48Â h when compared to HTK perfusion. WMO-II preserves kidney function as evidenced by the reduction in serum creatinine and potassium during graft transplantation