Improvement of Static and Dynamic Properties of Soft Clay Using High Pressure Jet Grout

A proposed subway project is located in an area marked by a number of soft clay layers situated at depths from 60 ft to 100 ft below the ground surface. With unconfined compressive strength less than 0.6 tsf these natural soils are not strong enough to support on coming heavy loads and vibrations that the subway may be subject to in future. Hence the soil was trial grouted in-situ using high pressure jet grout technique to improve the engineering properties of the natural clay. A series of static and dynamic property tests were carried out on 18 samples selected from the site. Results show that the static and dynamic strength of the grouted clay improved significantly and the improvement depends on several parameters like confining pressure, cement content and water/cement ratio. The study provides a reasonable estimate of the extent of improvement (with respect to natural soil) and leads towards a better understanding of the static and dynamic properties of cement-treated clays and their behavior under various conditions

Earthquake-Induced Lateral Displacement of a Landfill

In the wake of stability failure of the Kettleman Hills Waste Repository on March 19, 1988, the stability of landfill mass in earthquake-prone areas has become an important issue in the community. Based on a proposed landfill site in the Memphis, Tennessee area, this paper studies behaviors of landfills under various landfill and earthquake conditions (height and slope angle of the landfill, average unit weight of the landfill refuse, and peak acceleration and time duration of bedrock motion) by calculating lateral displacements induced by a design earthquake. Results indicate that lateral displacement of a landfill is proportional to the slope angle of the landfill, peak acceleration and time duration of bedrock motion, and is inversely proportional to the average unit weight of the landfill refuse. The slope angle of a landfill and the peak acceleration of bedrock motion have significant influence on the lateral displacement of a landfill compared with landfill height, average unit weight of landfill refuse and time duration of bedrock motion. Results also indicate that some landfill heights should be avoided to diminish landfill resonance, and the maximum slope angle of a landfill under certain seismic conditions depends on the internal friction angle of the landfill refuse. In addition, the lateral displacements calculated from actual and pseudo-accelerations are compared and discussed

Sorption-Desorption of Diuron in Subsurface Systems: An Investigation of Desorption Hysteresis

Sorption-desorption of diuron to a subsurface material was investigated by a variety of batch reactor experiments. The time needed to reach sorption equihbrium was longer than 45 days, while desorption equilibrium was apparently approached within 7 days. Nonlinear sorption-desorption equilibrium and desorption hysteresis were observed. The Freundlich equation was found to describe sorption-desorption equilibria best, with a Freundlich sorption exponent of 0.66, and an average desorption exponent of 0.23. Complex pattern sorption-desorption experiments were performed. The results of these experiments showed that the sorption-desorption process may be described by a Freundlich model: sorption exponent, desorption exponent, and sorption capacity constant, and the maximum equilibrium value achieved. Several possible explanations to describe the observed hysteresis were investigated. Nonattainment of equilibrium, loss of solute, artifact of the experimental methods, sorption to nonsettling particles, centrifugation effects, accumulated measurement error, and presence of an implicit-sorbate were found not to be the major cause of desorption hysteresis. A two-site model was developed to describe the sorption and desorption rates. This model assumes that two types of reaction sites exist on the solid-phase—fast and slow sites. The fast-sites sorb solute rapidly inducing an instantaneous equilibrium. The slow-sites are simulated by a first order mass transfer model. The two-site model provided a reasonable fit of the observed data.Master of Science in Environmental Engineerin

Fucosyltransferase 1 and 2 play pivotal roles in breast cancer cells.

FUT1 and FUT2 encode alpha 1, 2-fucosyltransferases which catalyze the addition of alpha 1, 2-linked fucose to glycans. Glycan products of FUT1 and FUT2, such as Globo H and Lewis Y, are highly expressed on malignant tissues, including breast cancer. Herein, we investigated the roles of FUT1 and FUT2 in breast cancer. Silencing of FUT1 or FUT2 by shRNAs inhibited cell proliferation in vitro and tumorigenicity in mice. This was associated with diminished properties of cancer stem cell (CSC), including mammosphere formation and CSC marker both in vitro and in xenografts. Silencing of FUT2, but not FUT1, significantly changed the cuboidal morphology to dense clusters of small and round cells with reduced adhesion to polystyrene and extracellular matrix, including laminin, fibronectin and collagen. Silencing of FUT1 or FUT2 suppressed cell migration in wound healing assay, whereas FUT1 and FUT2 overexpression increased cell migration and invasion in vitro and metastasis of breast cancer in vivo. A decrease in mesenchymal like markers such as fibronectin, vimentin, and twist, along with increased epithelial like marker, E-cadherin, was observed upon FUT1/2 knockdown, while the opposite was noted by overexpression of FUT1 or FUT2. As expected, FUT1 or FUT2 knockdown reduced Globo H, whereas FUT1 or FUT2 overexpression showed contrary effects. Exogenous addition of Globo H-ceramide reversed the suppression of cell migration by FUT1 knockdown but not the inhibition of cell adhesion by FUT2 silencing, suggesting that at least part of the effects of FUT1/2 knockdown were mediated by Globo H. Our results imply that FUT1 and FUT2 play important roles in regulating growth, adhesion, migration and CSC properties of breast cancer, and may serve as therapeutic targets for breast cancer

Comparison of extracorporeal shock wave lithotripsy running models between outsourcing cooperation and rental cooperation conducted in Taiwan

Background/PurposeWe conducted a retrospective study to compare the cost and effectiveness between two different running models for extracorporeal shock wave lithotripsy (SWL), including the outsourcing cooperation model (OC) and the rental cooperation model (RC).MethodsBetween January 1999 and December 2005, we implemented OC for the SWL, and from January 2006 to October 2011, RC was utilized. With OC, the cooperative company provided a machine and shared a variable payment with the hospital, according to treatment sessions. With RC, the cooperative company provided a machine and received a fixed rent from the hospital. We calculated the cost of each treatment session, and evaluated the break-even point to estimate the lowest number of treatment sessions to make the balance between revenue and cost every month. Effectiveness parameters, including the stone-free rate, the retreatment rate, the rate of additional procedures and complications, were evaluated.ResultsCompared with OC there were significantly less treatment sessions for RC every month (42.6±7.8 vs. 36.8±6.5, p=0.01). The cost of each treatment session was significantly higher for OC than for RC (751.6±20.0 USD vs. 684.7±16.7 USD, p=0.01). The break-even point for the hospital was 27.5 treatment sessions/month for OC, when the hospital obtained 40% of the payment, and it could be reduced if the hospital got a greater percentage. The break-even point for the hospital was 27.3 treatment sessions/month for RC. No significant differences were noticed for the stone-free rate, the retreatment rate, the rate of additional procedures and complications.ConclusionOur study revealed that RC had a lower cost for every treatment session, and fewer treatment sessions of SWL/month than OC. The study might provide a managerial implication for healthcare organization managers, when they face a situation of high price equipment investment

Sialylation of vasorin by ST3Gal1 facilitates TGF-β1-mediated tumor angiogenesis and progression.

ST3Gal1 is a key sialyltransferase which adds α2,3-linked sialic acid to substrates and generates core 1 O-glycan structure. Upregulation of ST3Gal1 has been associated with worse prognosis of breast cancer patients. However, the protein substrates of ST3Gal1 implicated in tumor progression remain elusive. In our study, we demonstrated that ST3GAL1-silencing significantly reduced tumor growth along with a notable decrease in vascularity of MCF7 xenograft tumors. We identified vasorin (VASN) which was shown to bind TGF-β1, as a potential candidate that links ST3Gal1 to angiogenesis. LC-MS/MS analysis of VASN secreted from MCF7, revealed that more than 80% of its O-glycans are sialyl-3T and disialyl-T. ST3GAL1-silencing or desialylation of VASN by neuraminidase enhanced its binding to TGF-β1 by 2- to 3-fold and thereby dampening TGF-β1 signaling and angiogenesis, as indicated by impaired tube formation of HUVECs, suppressed angiogenesis gene expression and reduced activation of Smad2 and Smad3 in HUVEC cells. Examination of 114 fresh primary breast cancer and their adjacent normal tissues showed that the expression levels of ST3Gal1 and TGFB1 were high in tumor part and the expression of two genes was positively correlated. Kaplan Meier survival analysis showed a significantly shorter relapse-free survival for those with lower expression VASN, notably, the combination of low VASN with high ST3GAL1 yielded even higher risk of recurrence (p = 0.025, HR = 2.967, 95% CI = 1.14-7.67). Since TGF-β1 is known to transcriptionally activate ST3Gal1, our findings illustrated a feedback regulatory loop in which TGF-β1 upregulates ST3Gal1 to circumvent the negative impact of VASN

Involvement of the nuclear high mobility group B1 peptides released from injured hepatocytes in murine hepatic fibrogenesis

AbstractThis study investigated the pro-fibrogenic role of high mobility group box 1 (HMGB1) peptides in liver fibrogenesis. An animal model of carbon tetrachloride (CCl4)-induced liver fibrosis was used to examine the serum HMGB1 levels and its intrahepatic distribution. The increased serum HMGB1 levels were positively correlated with elevation of transforming growth factor-β1 (TGF-β1) and collagen deposition during fibrogenesis. The cytoplasmic distribution of HMGB1 was noted in the parenchymal hepatocytes of fibrotic livers. In vitro studies confirmed that exposure to hydrogen peroxide and CCl4 induced an intracellular mobilization and extracellular release of nuclear HMGB1 peptides in clone-9 and primary hepatocytes, respectively. An uptake of exogenous HMGB1 by hepatic stellate cells (HSCs) T6 cells indicated a possible paracrine action of hepatocytes on HSCs. Moreover, HMGB1 dose-dependently stimulated HSC proliferation, up-regulated de novo synthesis of collagen type I and α-smooth muscle actin (α-SMA), and triggered Smad2 phosphorylation and its nuclear translocation through a TGF-β1-independent mechanism. Blockade with neutralizing antibodies and gene silencing demonstrated the involvement of the receptor for advanced glycation end-products (RAGE), but not toll-like receptor 4, in cellular uptake of HMGB1 and the HMGB1-mediated Smad2 and ERK1/2 phosphorylation as well as α-SMA up-regulation in HSC-T6 cells. Furthermore, anti-RAGE treatment significantly ameliorated CCl4-induced liver fibrosis. In conclusion, the nuclear HMGB1 peptides released from parenchymal hepatocytes during liver injuries may directly activate HSCs through stimulating HSC proliferation and transformation, eventually leading to the fibrotic changes of livers. Blockade of HMGB1/RAGE signaling cascade may constitute a therapeutic strategy for treatment of liver fibrosis

Epidemiology and Clinical Peculiarities of Norovirus and Rotavirus Infection in Hospitalized Young Children with Acute Diarrhea in Taiwan, 2009

Background/PurposeAcute diarrhea is one of the most common morbidities in pediatrics worldwide. We conducted a study to investigate the incidence of norovirus in young children hospitalized with acute diarrhea in Taiwan and its clinical peculiarity compared with rotavirus gastroenteritis.MethodsBetween January and December, 2009, patients younger than 5 years and admitted to hospital with acute diarrhea were randomly selected; and their stool samples were collected and tested for presence of rotavirus and norovirus by enzyme immunoassay and reverse transcription-polymerase chain reaction, respectively. The clinical manifestations and laboratory findings of the enrolled patients were analyzed.ResultsA total of 989 cases were enrolled with a mean age of 21.6 ± 13.7 months and a male proportion of 56.0%. Rotavirus and norovirus was detected in 20.2% and 14.6% of all patients, respectively. Genogroup II was the predominant strain of norovirus (80.6%). Children aged 6-36 months accounted for the majority of patients positive for rotavirus and norovirus (73.0% and 81.3%, respectively). The incidences of norovirus and rotavirus infection were higher during winter and early spring. Most patients with rotavirus and norovirus diarrhea experienced vomiting (74.9% vs. 74.8%, respectively) and fever (94.7% vs. 71.3%, respectively).ConclusionMost young diarrheal patients presenting with vomiting were likely to have norovirus or rotavirus infection. Patients with norovirus diarrhea experienced an absence of, or low-grade fever and longer duration of vomiting compared with those positive for rotavirus infection. A family history of current gastroenteritis may suggest the possibility of norovirus infection