Criterions, Prediction and Prevention of Loess Liquefaction

Although loess liquefaction is not very common during earthquakes in Northwest of China, it is disastrous if it happens. Both study and valid evidence from Haiyuan 8.5 Earthquake in 1920 and Tajikistan 5.9 Earthquake in 1989 have proved that loess liquefaction could be very disastrous under certain conditions. In this paper, the criterions of loess liquefaction are discussed to show that unlike typical liquefaction of sand, loess which falls into the category of both silt clay and clayey silt has unique characteristics during liquefaction test. To predict liquefaction of loess, a simple method based on laboratory test and field evidences using GIS is proposed. The prediction results and corresponding measure have been adopted in Seismic Design Code for Buildings in Lanzhou Urban Area. Finally, recent approach of treatment of loess with chemicals methods is developed, which may have some application implication as an simple and feasible treatment method against liquefaction of loess

The Geotechnical Hazard Induced by 8.1 Earthquake in West Pass of Kunlun Mountatin in China in 2001

On November 14, 2001, a great earthquake with a magnitude of Ms=8.1 occurred in the Qinhai-Tibet Plateau, China, which is called as the west pass of Kunlun mountain Ms8.1 earthquake. This earthquake is the largest and the first one with a magnitude greater than 8.0 in mainland China in the recent 50 years. It caused a large-scale deformation zone with a length of 426 km in frozen soil deposit in the plateau with a height of 4000-5500 meters above sea level. Some geotechnical hazards induced in the meizoseismal area, such as compression and tension failure of soil deposit, shaking landslides (collapse of slope and cliff), seismic settlement, sliding of glacier and snow. Unexpectedly, liquefaction occurred within the melting sand layer in frozen soil deposit on the banks of lakes and rivers. All the hazards were investigated in the field by the authors. This paper presents the results of the field investigation and tests made

Neuroprotective Effects of Pre-Treament with l-Carnitine and Acetyl-l-Carnitine on Ischemic Injury In Vivo and In Vitro

The therapeutic effect of stroke is hampered by the lack of neuroprotective drugs against ischemic insults beyond the acute phase. Carnitine plays important roles in mitochondrial metabolism and in modulating the ratio of coenzyme A (CoA)/acyl-CoA. Here, we investigate the neuroprotective effects of l-carnitine (LC) and Acetyl-l-carnitine (ALC) pre-treatment on ischemic insults under the same experimental conditions. We used a transient middle cerebral artery occlusion (MCAO) model to evaluate the protective roles of LC and ALC in acute focal cerebral ischemia in vivo and to understand the possible mechanisms using model of PC12 cell cultures in vitro. Results showed that ALC, but not LC, decreased infarction size in SD rats after MCAO in vivo. However, both LC and ALC pretreatment reduced oxygen-glucose deprivation (OGD)-induced cell injury and decreased OGD-induced cell apoptosis and death in vitro; at the same time, both of them increased the activities of super oxide dismutase (SOD) and ATPase, and decreased the concentration of malondialdehyde (MDA) in vitro. Thus, our findings suggested that LC and ALC pre-treatment are highly effective in the prevention of neuronal cell against ischemic injury in vitro, however, only ALC has the protective effect on neuronal cell injury after ischemia in vivo

Upregulation of Cyclin B1 by miRNA and its implications in cancer

It is largely recognized that microRNAs (miRNAs) function to silence gene expression by targeting 3′UTR regions. However, miRNAs have also been implicated to positively-regulate gene expression by targeting promoter elements, a phenomenon known as RNA activation (RNAa). In the present study, we show that expression of mouse Cyclin B1 (Ccnb1) is dependent on key factors involved in miRNA biogenesis and function (i.e. Dicer, Drosha, Ago1 and Ago2). In silico analysis identifies highly-complementary sites for 21 miRNAs in the Ccnb1 promoter. Experimental validation identified three miRNAs (miR-744, miR-1186 and miR-466d-3p) that induce Ccnb1 expression in mouse cell lines. Conversely, knockdown of endogenous miR-744 led to decreased Ccnb1 levels. Chromatin immunoprecipitation (ChIP) analysis revealed that Ago1 was selectively associated with the Ccnb1 promoter and miR-744 increased enrichment of RNA polymerase II (RNAP II) and trimethylation of histone 3 at lysine 4 (H3K4me3) at the Ccnb1 transcription start site. Functionally, short-term overexpression of miR-744 and miR-1186 resulted in enhanced cell proliferation, while prolonged expression caused chromosomal instability and in vivo tumor suppression. Such phenotypes were recapitulated by overexpression of Ccnb1. Our findings reveal an endogenous system by which miRNA functions to activate Ccnb1 expression in mouse cells and manipulate in vivo tumor development/growth

Java implementation of the domain algebra for nested relations

This thesis discusses the design and implementation of a relational database programming language, focusing on the domain algebra for nested relations. While the relational algebra provides operations to manipulate relations as data primitives, the domain algebra allows the manipulation of the attributes of relations. With the nested relational model, the domain algebra subsumes the functionality of the relational algebra. The conventional relational operations (e.g. selection and projection) may be applied to the attributes of a relation.The domain algebra for nested relations has many advantages. For example, the domain algebra makes the nesting and unnesting of relations very easy. This ensures that any hierarchical database schema can be validly translated into a conventional 1NF database schema. With the nested domain algebra, defining abstract data types for domains can be achieved as well.The system consists of three modules; the relational algebra, the domain algebra and computations. This thesis deals with the domain algebra module.The implementation is part of the jRelix project at McGill University. The most significant feature of jRelix is the support for the nested relations with an arbitrary but finite level of nesting. The Object-Oriented programming language Java was used exclusively during the implementation, which secures jRelix as a platform independent database programming language

The Primary Irradiation Damage of Hydrogen-Accumulated Nickel: An Atomistic Study

Nickel-based alloys have demonstrated significant promise as structural materials for Gen-IV nuclear reactors. However, the understanding of the interaction mechanism between the defects resulting from displacement cascades and solute hydrogen during irradiation remains limited. This study aims to investigate the interaction between irradiation-induced point defects and solute hydrogen on nickel under diverse conditions using molecular dynamics simulations. In particular, the effects of solute hydrogen concentrations, cascade energies, and temperatures are explored. The results show a pronounced correlation between these defects and hydrogen atoms, which form clusters with varying hydrogen concentrations. With increasing the energy of a primary knock-on atom (PKA), the number of surviving self-interstitial atoms (SIAs) also increases. Notably, at low PKA energies, solute hydrogen atoms impede the clustering and formation of SIAs, while at high energies, they promote such clustering. The impact of low simulation temperatures on defects and hydrogen clustering is relatively minor. High temperature has a more obvious effect on the formation of clusters. This atomistic investigation offers valuable insights into the interaction between hydrogen and defects in irradiated environments, thereby informing material design considerations for next-generation nuclear reactors

Pioglitazone Attenuates Drug-Eluting Stent-Induced Proinflammatory State in Patients by Blocking Ubiquitination of PPAR

The inflammatory response after polymer-based drug-eluting stent (DES) placement has recently emerged as a major concern. The biologic roles of peroxisome proliferator-activated receptor-γ (PPAR-γ) activators thiazolidinedione (TZD) remain controversial in cardiovascular disease. Herein, we investigated the antiinflammatory effects of pioglitazone (PIO) on circulating peripheral blood mononuclear cells (MNCs) in patients after coronary DES implantation. Methods and Results. Twenty-eight patients with coronary artery disease and who underwent DES implantations were randomly assigned to pioglitazone (30 mg/d; PIO) or placebo (control; Con) treatment in addition to optimal standard therapy. After 12 weeks of treatment, plasma concentrations of high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and matrix metalloproteinase-9 (MMP-9) were significantly decreased in PIO group compared to the Con group (P=0.035, 0.011, 0.008, and 0.012, resp.). DES-induced mRNA expressions of IL-6, TNF-α, and MMP-9 in circulating MNC were significantly blocked by PIO (P=0.031, 0.012, and 0.007, resp.). In addition, PIO markedly inhibited DES-enhanced NF-κB function and DES-blocked PPAR-γ activity. Mechanically, DES induced PPAR-γ ubiquitination and degradation in protein level, which can be totally reversed by PIO. Conclusion. PIO treatment attenuated DES-induced PPAR loss, NF-κB activation, and proinflammation, indicating that PIO may have a novel direct protective role in modulating proinflammation in DES era

Apoptotic mechanism of propofol-induced developmental toxicity in zebrafish embryos.

General anesthetics can cause neurological damage and long-term behavioral/cognitive impairment during fetal and early postnatal life. However, the adverse influence on embryo development induced by propofol is unclear. We used embryonic zebrafish to explore the effects of propofol on embryonic and larval growth and development, and the related apoptotic mechanism. Zebrafish embryos were immersed in propofol (1, 2, 3, 4, and 5 μg/ml) dissolved in E3 medium from 6 to 48 hours post fertilization (hpf). The survival rate, locomotion, heart rate, hatchability, deformity rate, and body length were analyzed at defined stages. Terminal deoxynucleotidyl transferase nick-end-labeling was used to detect zebrafish embryo apoptosis, and the expression levels of apoptosis-related genes were determined using quantitative real-time reverse transcription PCR and whole-mount in situ hybridization. Larvae at 48 hpf were anesthetized by immersion in E3 culture medium containing 2 μg/ml propofol, the reasonable anesthetic concentration for zebrafish embryos, which caused significant caudal fin dysplasia, light pigmentation, edema, hemorrhage, and spinal deformity, and decreased the hatchability, body length, and heart rate. The numbers of apoptotic cells in propofol-treated 12, 48 and 72 hpf embryos increased significantly, and the mRNA expression levels of intrinsic apoptosis pathway-related casp3a, casp3b, casp9, and baxb genes were upregulated, mainly in the head and tail. Propofol decreased apoptosis in the head and back of 24 hpf zebrafish, which was consistent with the mRNA expression analysis. Our findings demonstrated that zebrafish embryos and larvae exposed to propofol experienced developmental toxicity, which correlated with the intrinsic apoptosis pathway with casp3a, casp3b, casp9, and baxb as the key genes