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This document discusses a research paper that focuses on the behavior of extra-large and extra-extra-large monopiles in kaolin clay. The authors conducted a numerical study to investigate the behavior of monopiles with different diameters, the same length, and different loading heights. They also propose a normalization method to account for different pile sizes and loading heights. The findings suggest that the proposed normalization methods can unify the response of monopiles in clay, but further research is needed to consider the influence of section flexibility on monopile response. [Extracted from the article]

Piles have been widely used as foundations to resist lateral loads. For the design of a laterally loaded pile, one of the most important inputs is the ultimate soil resistance ( p ult = K ult D σ v ′ , where Kult is the ultimate lateral soil resistance coefficient, D is the pile diameter, and σ v ′ is the vertical effective stress). However, great discrepancy can be found in the existing design equations for piles in sand. To provide new insights and clarify the discrepancy in previous studies, in this study, a series of numerical simulations were performed on piles of different configurations using the finite element model validated by centrifuge pile tests. The computed results suggest that Kult is a function of depth ratios z/D and z/L for the flexible and rigid piles, respectively (where z is the absolute depth and L is the embedded pile length), and all existing design equations failed to reproduce the magnitude and distribution of Kult. Additionally, the Kult of horizontally translated fixed-head rigid piles exhibits the same pattern as that of free-head flexible piles, suggesting that the difference between free-head flexible piles and rigid piles is caused by the change of failure modes. [ABSTRACT FROM AUTHOR]

Undissolved gas bubbles, which are widely formed in marine sediments, could modify the behavior of the soil. To date, the cyclic behavior of fine-grained gassy soil has been rarely studied, limiting any reliable analysis of cyclically loaded offshore foundations in fine-grained gassy seabed. This study presents a series of undrained cyclic triaxial tests on normally consolidated (NC) fine-grained gassy soil. Each sample was charged with the same amount of N2 gas before consolidation. Then, samples were consolidated to an identical mean operative stress (total stress minus pore water pressure) of 200 kPa, but at different initial pore water pressures (uw0=0–600 kPa) before cycling. Compared with a saturated sample, the inclusion of a small amount of gas bubbles can either significantly decrease the level of cyclic stiffness degradation when the initial pore water pressure uw0 is lower than a threshold value (150 kPa in this study), or vice versa. This behavior is associated with two competing mechanisms during the cyclic shearing: (1) collapse of gas-filled pores, which increases cyclic pore water pressure (CPWP), and therefore stiffness degradation; and (2) partial water drainage into gas cavities, which reduces CPWP and stiffness degradation. The former and the latter are likely to dominate at relatively high and low uw0 , respectively. This implies that water depth would significantly influence the cyclic deformation and stiffness degradation of offshore foundations in fine-grained gassy sediments. [ABSTRACT FROM AUTHOR]

OBJECTIVE : The aim of this study was to investigate the influence of micro ribonucleic acid (miR)-204 on rats with myocardial infarction by targeting the silent information regulator 1 (SIRT1)/p53 signaling pathway. MATERIALS AND METHODS: A total of 36 Sprague-Dawley rats were randomly divided into three groups, including: sham-operation group (n=12), model group (n=12) and miR-204 mimics group (n=12). The rats in the sham-operation group only underwent thoracotomy, without myocardial infarction injury. Meanwhile, the rats in model group and miR-204 mimics group were utilized to establish the models of myocardial infarction, and then, intervened with normal saline and miR-204 mimics, respectively. The morphology of myocardial tissues was observed via hematoxylin-eosin (HE) staining. Immunofluorescence was performed to detect the expression of Caspase-3. Target genes of miR-204 were analyzed using bioanalysis software. Western blotting (WB) assay was applied to measure the relative protein expression of SIRT1. MiR-204 expression and the messenger RNA (mRNA) expressions of SIRT1 and p53 were measured via quantitative Polymerase Chain Reaction (qPCR). Furthermore, cell apoptosis was determined through terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. RESULTS: HE staining showed that the morphology of myocardial tissues was normal in sham-operation group. Severe myocardial tissue injury was visible in model group, and the injury was relieved in miR-204 mimics group when compared with model group. The results manifested that the positive expression of Caspase-3 in cardiac tissues increased remarkably in the model group and miR-204 mimics group in comparison with sham-operation group (p<0.05). Meanwhile, it was evidently lower in miR-204 mimics group than model group (p<0.05). Based on the analysis via bioanalysis software, SIRT1 was the target gene of miR-204. WB results revealed that the relative protein expression level of SIRT1 was elevated notably in the other two groups compared with the 2sham-operation group (p<0.05). However, it was markedly lowered in miR-204 mimics group in contrast with model group (p<0.05). QRT-PCR results demonstrated that the model group and miR-204 mimics group exhibited distinctly lower expression of miR-204 but higher mRNA expressions of SIRT1 and p53 than sham-operation group (p<0.05). However, miR-204 mimics group exhibited prominently higher expression of miR-204 but lower mRNA expressions of SIRT1 and p53 than model group (p<0.05). Finally, the results of TUNEL assay demonstrated that the apoptosis rate increased remarkably in the model group and miR-204 mimics group when compared with sham-operation group (p<0.05). However, it decreased notably in miR-204 mimics group in comparison with model group (p<0.05). CONCLUSIONS: MiR-204 reduces the apoptosis level in rats with myocardial infarction via targeted inhibition of the SIRT1/p53 signaling pathway. [ABSTRACT FROM AUTHOR]

Extracellular vesicles (EVs) are small lipid-encapsulated vesicles secreted from specific cells that can be taken up by other cells, thereby allowing for the efficient transport of macromolecules such as lipids, proteins, and nucleic acids between tissues and organs in vivo. These EVs have been found to play critical roles in normal tissue homeostasis and disease development, serving to regulate complex processes, including inflammation, immunity, and angiogenesis. At present, the leading global cause of the end-stage renal disease (ESRD) is diabetic kidney disease (DKD), with the prevalence of this latter condition being predicted to increase in the near future due to rising type 2 diabetes mellitus (T2DM) incidence. Recent work from several research groups has highlighted a potential role for EVs in the development of DKD. The present review, therefore, serves to explore the relevance of EVs to the development, detection, and treatment of DKD in an effort to better understand this complex disease state. [ABSTRACT FROM AUTHOR]

Both finite element models and multi-body models of human head-neck complex had been widely used in neck injuries analysis, as the former could be used to generate detailed stress strain information and the later could generate dynamic responses with high efficiency. Sometimes, detailed stress and strain information were hoped to be obtained more efficiently, but current methods were not effective enough when they were used to analyze responses of human head neck complex to long duration undulate accelerations. In this paper, a two-step procedure for ‘parallel’ development and ‘sequential’ usage of a pair of human head neck models was discussed. The pair of models contained a finite element model and a multi-body model, which were developed based on the coupling ‘parallel’ procedure using the same bio-realistic geometry. After being validated using available data, the pair of human neck models were applied to analyze biomechanical responses of pilot’s neck during arrested landing operation according to the ‘sequential’ procedure, because typical sustained undulate accelerations usually appeared during such processes. The results, including both kinematic and detailed biomechanical responses of human head-neck complex, were obtained with preferable efficiency. This research provided an effective way for biomechanical analysis of human head neck responses to sustained undulate accelerations. [ABSTRACT FROM AUTHOR]

The Lawn-Evans-Marshall model for Vickers-induced crack driving force is widely applied for determining fracture toughness of ceramic materials, yet its simplification that the volumes of Vickers impression and equivalent expanding cavity merely depend on the half-diagonal length of residual impression will bring significant error. In this work, the model is modified by considering the influence of elastic recovery in depth after completely unloading on the volumes. As a result, a new expression for crack driving force is obtained and correspondingly a new fracture toughness formula is presented based on the modified model, which is expressed as the well-known Anstis formula with a different constant multiplied by the ratio of residual impression depth to the maximum indentation depth. Both finite element analysis and experimental results demonstrate the effectiveness of the proposed formula and, especially, that it works much better than Anstis formula on materials with large ratio of hardness to elastic modulus. [ABSTRACT FROM AUTHOR]

Although Toyoura sand has been widely used as a standard material for physical model tests (particularly centrifuge model tests), its path-dependent stiffness degradation curves are rarely reported in the literature. This leads to difficulties in back-analyzing and understanding the physical tests involving significant changes in the direction of stress paths (such as unloading problems). In this study, path-dependent stiffness degradation curves of medium-dense Toyoura sand were determined by carrying out a series of stress-path triaxial tests, with local strain measurements. In the triaxial tests, four typical recent stress histories (changes of path direction = 0, 90, -90, and 180°) were simulated. The measured small strain stiffnesses of Toyoura sand were then used to calibrate an advanced hypoplastic model that accounts for pathdependent soil stiffness at small strains. To justify the validity of the calibrated hypoplastic model and model parameters, a Type A numerical prediction and a centrifuge model test were carried out to simulate a typical unloading problem (i.e., excavation) in medium-dense Toyoura sand. Triaxial test results show that a 180° reversal in the direction of the stress path increased the initial secant modulus of Toyoura sand by eight times. The path dependency of soil stiffness, however, vanished when the deviatoric strain exceeded 0.3%. The ground deformations (resulting from excavation) predicted by the numerical analysis show reasonable agreement with the measured data from the centrifuge test. This suggests the potential applicability of the calibrated soil model and its model parameters in predicting or back-analyzing other physical model tests in Toyoura sand. [ABSTRACT FROM AUTHOR]

In this study, an anisotropic thermal-elastic-plastic (TEP) constitutive model is developed for soft clays. Two yield surfaces, namely the current yield surface and reference yield surface, are adopted to characterize the development of plastic volumetric strain (i.e., the unique internal variable of the two surfaces) due to either mechanical or thermal loading. The model is formulated based on the framework of the Modified Cam-Clay model, with only two additional parameters introduced (i.e., α and θ), to account for stress-induced anisotropy and thermal-induced translation of compression curves, respectively. Based on the model, a simplified equation is proposed to quantify the effect of drained heating on the undrained shear strength of clay. The predictive capability of the proposed model and the simplified equation for undrained shear strength are verified against published results of temperature-controlled triaxial tests on soft clay. By assessing seven different types of clays, the thermal-related parameters θ are found to almost linearly increase with the plastic index (Ip) of soil. Empirical correlations are then proposed for a quick approximation of θ, in case that data from temperature-controlled tests are not readily available. [ABSTRACT FROM AUTHOR]

Twenty castrated Boer crossbred goats were used in the present study with two treatments to examine the effect of dietary replacement of ordinary rice with red yeast rice on nutrient utilization, enteric methane emission and ruminal archaea structure and composition. Two treatment diets contained (DM basis) 70.0% of forage, 21.8% of concentrates and 8.2% of either ordinary rice (control) or red yeast rice (RYR). Nutrient utilization was measured and enteric methane emissions were determined in respiration chambers. Results showed that RYR had significantly lower digestibility of N and organic matter compared to control group. However, feeding red yeast rice did not affect N retention as g/d or a proportion of N intake, and reduced heat production as MJ/d or as a proportion of metabolizable energy intake, thus leading to a higher proportion of metabolizable energy intake to be retained in body tissue. RYR also had significantly lower methane emissions either as g/d, or as a proportion of feed intake. Although feeding red yeast rice had no negative effect on any rumen fermentation variables, it decreased serum contents of total cholesterol, triglycerides, HDL-cholesterol and LDL-cholesterol. In the present study, 75616 archaeal sequences were generated and clustered into 2364 Operational Taxonomic Units. At the genus level, the predominant archaea in the rumen of goats was Methanobrevibacter, which was significantly inhibited with the supplementation of red yeast rice. In conclusion, red yeast rice is a potential feed ingredient for mitigation of enteric methane emissions of goats. However, caution should be taken when it is used because it may inhibit the digestibility of some nutrients. Further studies are required to evaluate its potential with different diets and animal species, as well as its effects on animal health and food safety. [ABSTRACT FROM AUTHOR]

Reactor simulation is an important source of uncertainties for a reactor neutrino experiment. Therefore, how to evaluate the antineutrino flux uncertainty results from reactor simulation is an important question. In this study, a method of the antineutrino flux uncertainty result from reactor simulation was proposed by considering the correlation coefficient. In order to use this method in the Daya Bay antineutrino experiment, the open source code DRAGON was improved and used for obtaining the fission fraction and correlation coefficient. The average fission fraction between DRAGON and SCIENCE code was compared and the difference was less than 5% for all the four isotopes. The uncertainty of fission fraction was evaluated by comparing simulation atomic density of four main isotopes with Takahama-3 experiment measurement. After that, the uncertainty of the antineutrino flux results from reactor simulation was evaluated as 0.6% per core for Daya Bay antineutrino experiment. [ABSTRACT FROM AUTHOR]

This paper reports a field study on the downdrag and dragload of two pairs of bored piles installed in consolidating ground in the Zhejiang coastal area, China. During and after the construction of a 2.5-m-high embankment, the dragload and downdrag induced on the four piles, surface and subsurface soil settlement, pore water pressure, and lateral earth pressure were monitored. The field measurements show that the maximum dragloads in piles founded on relatively stiffer (end-bearing pile) and relatively softer layers (floating pile) ranged from 1,198 to 1,238 kN and from 798 to 870 kN, respectively. This suggests that the dragload in a floating pile can be one-third less than that in an end-bearing pile with similar geometries and embedded in the same consolidating ground. Deduced β values above the neutral plane (NP) in the clay strata ranged from 0.28 to 0.3, respectively. A much smaller β (0.04-0.06) was found below the NP. The existing analytical solutions overestimated the depth of the NP, leaving the structural design of the piles on the safe side. [ABSTRACT FROM AUTHOR]

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Li2MnO3 based layered Li-rich materials as promising cathode candidates of Li ion batteries (LIBs) have attracted much recent attention mainly owing to their superior high specific capacity and high working voltage. To date, although researchers have put much effort to this family of materials, there are still a number of issues under debates in the fundamental understanding of the crystal structures and the electrochemical reaction mechanisms, before the materials can be ready for practical applications. In this review article, we address the recent progress of this group of Li-rich cathode materials with a good hope to better understanding of the relationships among composition, crystal structure and electrochemical reaction mechanisms. In addition, the use of advanced microscopic characterisation and the strategies of novel material designs will also be discussed for better cathode design for LIBs. [ABSTRACT FROM AUTHOR]

Cisplatin (CDDP) is one of the most frequently used antitumor agents, but its application is significantly limited by its hepatotoxicity. In the present study, we investigated the effects of crocin against CDDP-induced oxidative stress and apoptosis in the liver of Kunming mice. Crocin was administered to the mice once daily for 7 consecutive days at the doses of 6.25 and 12.5 mg/kg body weight orally. On day 1, a single intraperitoneal injection of CDDP was given at the dose of 10 mg/kg body weight. Crocin treatment significantly improved CDDP-induced hepatic damage as indicated by serum aspartate aminotransferase and alanine aminotransferase levels. Crocin relieved CDDP-induced oxidative stress by reducing malondialdehyde level and recovering the levels of glutathione and antioxidant enzymes such as superoxide dismutase, catalase, and glutathione peroxidase. In addition, liver histopathology indicated that crocin alleviated CDDP-induced focal necrosis. Immunohistochemical staining and Western blot analysis showed that crocin significantly decreased the levels of phospho-p38 mitogen-activated protein kinase (MAPK), tumor protein 53 (p53), and cleaved caspase-3. Taken together, our data suggest that crocin provides protective effects against CDDP-induced hepatoxicity by attenuating oxidative stress and inhibiting the activation of p38 MAPK, p53, and caspase-3. [ABSTRACT FROM PUBLISHER]