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Quick screening of pareto-optimal operating conditions for expanding solvent-steam assisted gravity drainage using hybrid multi-objective optimization approach
No full textSolvent-steam mixture is a key factor in controlling the economic efficiency of the solvent-aided thermal injection process for producing bitumen in a highly viscous oil sands reservoir. This paper depicts a strategy to quickly provide trade-off operating conditions of the Expanding Solvent-Steam Assisted Gravity Drainage (ES-SAGD) process based on Pareto-optimality. Response surface models are employed to evaluate multiple ES-SAGD scenarios at low computational costs. The surrogate models play a role of objective-estimators in the multi-objective optimization that provides qualified ES-SAGD scenarios regarding bitumen recovery, steam-energy efficiency, and solvent-energy efficiency. The developed hybrid approach detects positive or negative correlations among the performance indicators of the ES-SAGD process. The derived Pareto-optimal operating conditions give flexibility in field development planning and thereby help decision makers determine the operating parameters of the ES-SAGD process based on their preferences. © 2017 by the authors.Ministry of Science, ICT and Future Plannin
A novel indeno[1,2-b] pyridinone derivative, a DNA intercalative human topoisomerase IIα catalytic inhibitor, for caspase 3-independent anticancer activity
No full textA novel 2-(furan-2-yl)-4-(pyridin-2-yl)-5H-indeno[1,2-b]pyridin-5-one (TI-1-190) was synthesized using a simple microwave-assisted method and its mode of action was systematically characterized. It is a DNA intercalative human topoisomerase IIα catalytic inhibitor with much stronger activity and less DNA toxicity than etoposide, a topoisomerase II poison. TI-1-190 displays caspase 3-independent anticancer activity, unlike etoposide. © 2017 The Royal Society of Chemistry
Effects of adrenal androgen levels on bone age advancement in prepubertal children: Using the Ewha birth and growth cohort study
No full textBone age (BA) advancement in prepubertal children may be associated with earlier onset of puberty and obesity. This study aimed to define the effects of adrenal androgen levels on the advancement of BA in prepubertal children, independent of obesity. During July and August 2011, we examined BA in 200 prepubertal children aged 7-9 years who were part of the Ewha Birth & Growth Cohort Study. BA was assessed by the Greulich-Pyle method. An index of BA advancement was calculated as the ratio of BA to chronological age (CA) (BA/CA), and this ratio was classified into 3 tertiles. We analyzed the relationship between BA advancement and anthropometric characteristics and adrenal hormone levels. The number of overweight children increased from the first group to the third group (PTrend = 0.03). The levels of adrenal androgens showed a significant positive correlation with the tertile groups after adjusting for age and sex (testosterone: r = 0.26, P < 0.001; dehydroepiandrosterone: r = 0.21, P < 0.001; androstenedione: r = 0.20, P < 0.001). Further, after controlling for body mass index (BMI), sex, and age, the BA/CA was found to be positively correlated with androstenedione (β = 0.04, R2= 3.7%) and testosterone levels (β = 0.05, R2= 4.7%). Based on our results, it is suggested that adrenal androgen levels are associated with BA advancement independent of BMI. © 2017 The Korean Academy of Medical Sciences
Exploiting I/O reordering and I/O interleaving to improve application launch performance
No full textApplication prefetchers improve application launch performance through either I/O reordering or I/O interleaving. However, there has been no proposal to combine the two techniques together,missing the opportunity for further optimization. We present a new application prefetching technique to take advantage of both the approaches. We evaluated our method with a set of applications to demonstrate that it reduces cold start application launch time by 50%, which is an improvement of 22% from the I/O reordering technique. © 2017 ACM 1553-3077/2017/02-ART2 $15.00.Ministry of Educatio
Phosphorylated Akt Expression as a Favorable Prognostic Factor for Patients Undergoing Curative Resection and Adjuvant Chemoradiotherapy for Proximal Extrahepatic Bile Duct Cancer
No full textObjectives: To evaluate the prognostic significance of phosphorylated Akt (p-Akt), phosphorylated mammalian target of rapamycin (p-mTOR), and total phosphatase and tensin homolog deleted on chromosome 10 (PTEN) expressions in patients undergoing adjuvant chemoradiotherapy (CRT) for proximal extrahepatic bile duct (EHBD) cancer. Methods: Sixty-three patients with proximal EHBD cancer who underwent curative resection followed by adjuvant CRT were enrolled into this study. Postoperative radiotherapy was delivered to tumor bed and regional lymph nodes up to a median of 40 Gy (range, 40 to 54 Gy). Fifty-nine patients also received fluoropyrimidine chemotherapy as a radiosensitizer. p-Akt, p-mTOR, and PTEN expression were assessed with immunohistochemical staining on the tissue microarray. Results: p-Akt, p-mTOR, and PTEN were expressed in 23 (36.5%), 17 (27.0%), and 24 patients (38.1%), respectively. p-Akt expression was associated with distant metastasis and overall survival (OS), but not with locoregional recurrence. The 5-year distant metastasis-free and OS rates were 25.8% versus 58.2% (P=0.007), and 27.5% versus 50.2% (P=0.0167) in patients with negative and positive expression, respectively. On multivariate analysis, nodal involvement was the only significant prognosticator predicting inferior distant metastasis-free survival (P=0.0105), whereas p-Akt expression had a borderline significance (P=0.0541). As for OS, p-Akt expression was a marginally significant prognosticator (P=0.0635), whereas other risk factors lost the statistical significance. Conclusion: p-Akt expression tended to be associated with a favorable prognosis in patients undergoing curative resection followed by adjuvant CRT for proximal EHBD cancer. Copyright © 2014 Wolters Kluwer Health, Inc. All rights reserved
Role of adjuvant radiotherapy for localized extrahepatic bile duct cancer
No full textObjective: To evaluate the benefit of adjuvant radiotherapy (RT) after surgical resection for extrahepatic bile duct (EHBD) cancer. Methods: From 1997 to 2015, 59 patients with EHBD cancer were the subject of this study; 36 patients not undergoing adjuvant treatment after surgery (observation group) and 23 patients receiving adjuvant RT (RT group) were compared. Microscopic residual disease (R1) was in 9 (25%) patients and 5 (22%) patients, and macroscopic residual disease (R2) was in 2 (6%) patients and 6 (26%) patients in the observation and RT groups, respectively. Adjuvant RT was delivered to the tumour bed and regional lymph nodes up to 50.4Gy (range, 45-61Gy). Results: With a median follow-up of 19 months, local recurrence was observed in 10 (28%) patients and 2 (9%) patients in the observation and RT groups, respectively. On univariate analysis, the 5-year local recurrence-free survival (LRFS) rates were 50% in the observation group and 54% in the RT group (p=0.401). The 5-year overall survival (OS) rates were 29.3% in the observation group and 26.3% in the RT group (p=0.602). On multivariable analysis, however, adjuvant RT significantly improved LRFS [hazard ratio (HR), 0.310; 95% confidence interval (CI), 0.100-0.963; p=0.043] and had a trend towards increased OS (HR, 0.491; 95% CI, 0.219-1.102; p=0.085). Resection margin (RM) status was also correlated with LRFS (HR for R1 6.134, 95% CI 2.051-18.344; and HR for R2 18.551, 95% CI 3.680-93.520; p<0.001) and OS (HR for R1 1.816, 95% CI 0.853-3.867; and HR for R2 3.564, 95% CI 1.175-10.809; p=0.054). Conclusion: RM status was a significant prognosticator of EHBD cancer, and adjuvant RT improved local control rate; thereby, survival rate might be increased. Advances in knowledge: The benefit of adjuvant RT in EHBD cancer was demonstrated via comparison with observation group. © 2017 The Authors. Published by the British Institute of Radiology
Nanocarbons as electron donors and acceptors in photoinduced electron-transfer reactions
No full textNanocarbons composed of hybridized sp2 carbons such as fullerenes, carbon nanotubes (CNTs), carbon nanohorns (CNHs) and graphene have been successfully utilized as electron acceptors in electron donor-acceptor hybrids for photoinduced electron-transfer reactions to mimic well the function of the photosynthetic reaction center. However, sp2 hybridized nanocarbons can also be used as electron donors when higher fullerenes such as C76 and C78 or endohedral metallofullerenes are employed or when nanocarbons are combined with relatively strong electron acceptors. This paper focuses on photoinduced electron-transfer reactions of nanocarbons including fullerenes, CNTs, CNHs and graphene, which act as not only as electron acceptors but also as electron donors with strong electron acceptors such as tetracyanoethylene (TCNE) and tetracyano-p-quinodimethan (TCNQ) to produce the radical cations efficiently because of small reorganization energies of electron transfer. Alternatively the oxidizing ability of electron acceptors was enhanced by binding Lewis acids to the radical anions, which enabled to oxidize nanocarbons. The important roles of nanocarbons such as fullerenes, carbon nanotubes and graphenes on the stability of rapidly emerging perovskite based solar cells with high power conversion efficiency have also been discussed in this paper. © The Author(s) 2017. Published by ECS. All rights reserved.Japan Science and Technology Agenc
Severe glyphosate-surfactant intoxication: Successful treatment with continuous renal replacement therapy
No full textGlyphosate-surfactant is one of the most commonly used herbicides in the world. Its key component, glyphosate, is a competitive inhibitor of the shikimate pathway, a metabolic pathway found only in plants. However, severe intoxication, including lethal cases by ingestion of, glyphosate-surfactant has been reported. We describe the full recovery of two patients from glyphosate-polyoxyethyleneamine surfactant intoxication and multi-organ system failure following continuous renal replacement therapy. Both patients developed persistent shock, acute kidney injury, lactic acidosis, hyperkalaemia and multi-organ failure despite of resuscitation. We believe that continuous renal replacement therapy should be initiated immediately for removal of glyphosate-polyoxyethyleneamine surfactant in patients with signs of cardiopulmonary compromise, lactic acidosis, and renal failure. We propose the addition of glyphosate-polyoxyethyleneamine surfactant to the list of toxins for which early haemodialysis should be indicated. © 2017, Medcom Limited. All rights reserved
Suppression of lipopolysaccharide-induced neuroinflammation by morin via MAPK, PI3K/Akt, and PKA/HO-1 signaling pathway modulation
No full textMorin is a flavonoid isolated from certain fruits and Chinese herbs and is known to possess various medicinal properties. In this study, we investigated the anti-inflammatory effects of morin on lipopolysaccharide (LPS)-induced microglial activation, both in vitro and in vivo. We found that morin inhibited inducible nitric oxide synthase (iNOS) and pro-inflammatory cytokines in LPS-stimulated BV2 microglial cells. Furthermore, morin suppressed the microglial activation and cytokine expression in the brains of LPS-stimulated mice. Subsequent mechanistic studies revealed that morin inhibited the action of LPSactivated mitogen- Activated protein kinases (MAPKs), protein kinase B (Akt) phosphorylation, nuclear factor-κB (NF-κB), and activating protein-1 (AP-1). Further, the phosphorylation and DNA binding activity of cAMP responsive element binding protein (CREB) was enhanced by morin. Moreover, morin suppressed the LPS-induced expression of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunits, while it increased heme oxygenase-1 (HO-1) expression and nuclear factor erythroid 2- related factor 2 (Nrf2) activation. Therefore, our data suggest that morin exerts anti-inflammatory effects in LPS-stimulated microglia by downregulating MAPK and phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathways while upregulating protein kinase A (PKA)/CREB and Nrf2/HO-1 signaling pathways. © 2016 American Chemical Society.Ministry of Science ICT and Future Plannin
Characterization and suppression of stripe artifact in velocity-selective magnetization-prepared unenhanced MR angiography
No full textPurpose: To characterize and suppress stripe artifact associated with velocity-selective (VS) magnetization for unenhanced MRA. Methods: Extended phase graph formalism was used to show that the stripe artifact contains multiples of the fundamental frequency that is determined by the area of unipolar VS gradient. Four VS preparation pulses whose excitation profiles are spatially shifted by quarter the fundamental period of the stripes, were applied alternately. For further suppression of the artifact, k-space data at k(z) = 0 were averaged over the 4 VS preparations. The proposed schemes were tested in a chicken breast phantom and healthy human subjects. Results: When the standard VS preparation scheme was used, stripe artifact was shown in all the reconstructed images and appeared as artifactual peaks in k-space that corresponded to the first and second order harmonics of the fundamental frequency. Alternate application of the 4 phase-shifted VS preparation pulses suppressed the stripes, but not completely, as evidenced by residual erroneous peaks in k-space. After the k-space averaging, the stripe artifact was nearly eliminated. Conclusion: Stripe artifact in VS-MRA consists of multiples of the fundamental frequency and can be effectively suppressed through alternate application of phase-shifted VS preparations along with k-space averaging