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Recently, a huge amount of sulfur has been produced as a byproduct of petroleum refining processes in Korea. Sulfur concrete is made of modified sulfur binder instead of cement paste, which has advantages of reducing CO2 emission from cement industry as well as utilizing surplus sulfur. Also, sulfur concrete is a sustainable material that can be repetitively recycled. In this study, the physical properties of sulfur concrete are experimentally investigated. From the test results, sulfur concrete showed compressive strengths higher than at least 50MPa. Also, the unit weight, modulus of elasticity and splitting tensile strength of sulfur concrete was similar to that of Portland cement concrete (PCC). The coefficient of thermal expansion of sulfur concrete was a little larger than that of Portland cement concrete and sulfur concrete with mineral filler is helpful to lower the coefficient of thermal expansion. recycled aggregate sulfur concrete resulted in a slight reduction in the compressive strength, but sulfur concrete with recycled aggregate can achieve the high strength characteristics.clos

Congenital Angiodysplasia in a Woman Presenting with Idiopathic Jejunal Varicosis on Angiography

Angiography is a useful diagnostic tool in cases with massive gastrointestinal bleeding such as angiodysplasia and varicosis when endoscopy is not available. Angiodysplasia and varicosis have distinguishable characteristic features on angiography, such as the presence of a nidus, visible late-draining veins, and the typical vascular tuft. We recently treated a rare case of congenital angiodysplasia without the characteristic angiodysplasia features on angiography. Instead, the patient presented with a very rare case of idiopathic jejunal varicosis. A 42-year-old woman visited the emergency room with the chief complaint of melena for three days and a hemoglobin level of 5.9 g/dL. An abdominal CT angiogram showed varicosis at the jejunal mesentery. Angiography of the superior and inferior mesenteric arteries showed tortuous and dilated jejunal and ileal branches during the venous phase, suggesting a vascular malformation such as varicosis of the jejunum. Surgical exploration with intraoperative endoscopy revealed diffuse engorged veins and a 1.0-cm-diameter superficial ulcer covered with a blood clot that was 70 cm from the ligament of Treitz. A 100-cm segment of jejunum was resected. Histological examination revealed that the lesion was angiodysplasia, not varicosis. The final diagnosis was congenital angiodysplasia

Safety and Efficacy of Second-Generation Everolimus-Eluting Xience V Stents Versus Zotarolimus-Eluting Resolute Stents in Real-World Practice Patient-Related and Stent-Related Outcomes From the Multicenter Prospective EXCELLENT and RESOLUTE-Korea Registries

ObjectivesThis study sought to compare the safety and efficacy of the Xience V/Promus everolimus-eluting stent (EES) (Abbott Vascular, Temecula, California) with the Endeavor Resolute zotarolimus-eluting stent (ZES-R) (Medtronic Cardiovascular, Santa Rosa, California) in “all-comer” cohorts.BackgroundOnly 2 randomized controlled trials have compared these stents.MethodsThe EXCELLENT (Efficacy of Xience/Promus Versus Cypher to Reduce Late Loss After Stenting) and RESOLUTE-Korea registries prospectively enrolled 3,056 patients treated with the EES and 1,998 patients treated with the ZES-R, respectively, without exclusions. Stent-related composite outcomes (target lesion failure [TLF]) and patient-related composite outcomes were compared in crude and propensity score-matched analyses.ResultsOf 5,054 patients, 3,830 (75.8%) had off-label indication (2,217 treated with EES and 1,613 treated with ZES-R). The stent-related outcome (82 [2.7%] vs. 58 [2.9%], p = 0.662) and the patient-related outcome (225 [7.4%] vs. 153 [7.7%], p = 0.702) did not differ between EES and ZES-R, respectively, at 1 year, which was corroborated by similar results from the propensity score-matched cohort. The rate of definite or probable stent thrombosis (18 [0.6%] vs. 7 [0.4%], p = 0.306) also was similar. In multivariate analysis, off-label indication was the strongest predictor of TLF (adjusted hazard ratio: 2.882; 95% confidence interval: 1.226 to 6.779; p = 0.015).ConclusionsIn this robust real-world registry with unrestricted use of EES and ZES-R, both stents showed comparable safety and efficacy at 1-year follow-up. Overall incidences of TLF and definite stent thrombosis were low, even in the patients with off-label indication, suggesting excellent safety and efficacy of both types of second-generation drug-eluting stents

Randomized Trial of Stents Versus Bypass Surgery for Left Main Coronary Artery Disease 5-Year Outcomes of the PRECOMBAT Study

AbstractBackgroundIn a previous randomized trial, we found that percutaneous coronary intervention (PCI) was not inferior to coronary artery bypass grafting (CABG) for the treatment of unprotected left main coronary artery stenosis at 1 year.ObjectivesThis study sought to determine the 5-year outcomes of PCI compared with CABG for the treatment of unprotected left main coronary artery stenosis.MethodsWe randomly assigned 600 patients with unprotected left main coronary artery stenosis to undergo PCI with a sirolimus-eluting stent (n = 300) or CABG (n = 300). The primary endpoint was a major adverse cardiac or cerebrovascular event (MACCE: a composite of death from any cause, myocardial infarction, stroke, or ischemia-driven target vessel revascularization) and compared on an intention-to-treat basis.ResultsAt 5 years, MACCE occurred in 52 patients in the PCI group and 42 patients in the CABG group (cumulative event rates of 17.5% and 14.3%, respectively; hazard ratio [HR]: 1.27; 95% confidence interval [CI]: 0.84 to 1.90; p = 0.26). The 2 groups did not differ significantly in terms of death from any cause, myocardial infarction, or stroke as well as their composite (8.4% and 9.6%; HR, 0.89; 95% CI, 0.52 to 1.52; p = 0.66). Ischemia-driven target vessel revascularization occurred more frequently in the PCI group than in the CABG group (11.4% and 5.5%, respectively; HR: 2.11; 95% CI: 1.16 to 3.84; p = 0.012).ConclusionsDuring 5 years of follow-up, our study did not show significant difference regarding the rate of MACCE between patients who underwent PCI with a sirolimus-eluting stent and those who underwent CABG. However, considering the limited power of our study, our results should be interpreted with caution. (Bypass Surgery Versus Angioplasty Using Sirolimus-Eluting Stent in Patients With Left Main Coronary Artery Disease [PRECOMBAT]; NCT00422968

Surface wave transmission to monitor recovery in crack depth

The main objective of this research project is to investigate the transmission of surface wave across a crack. Lab-scale experimental test and numerical simulation were conducted to characterize the transmission of surface wave and identify limitations of current surface wave for cementitious materials and concrete structures with potential application in the construction industry. Two-dimensional finite element model for surface wave propagation along surface is investigated for different crack depth from crack free to 20 mm and 40 mm. Change in surface wave transmission parameters including both transmission function and spectral energy transmission ratios are investigated. Finally, technical improvement points of surface wave transmission based crack depth estimation methods are discussed in the last section

Stress-Deformation Responses of Steel Fiber-Reinforced Cementitious Composites in Direct Tension and Flexure

The purpose of the present study is to investigate effects of the geometry and volume fraction of steel fibers on the stress-deformation response of fiber-reinforced cementitious composites subjected to compression, direct tension, or flexure

Alzheimer's disease and Notch signaling

Cleavage of the amyloid precursor protein (APP) by [gamma]-secretase generates a neurotoxic amyloid [beta]-peptide (A[beta]) that is thought to be associated with the neurodegeneration observed in Alzheimer's disease (AD) patients. Presenilin is the catalytic member of the [gamma]-secretase proteolytic complex and mutations in presenilins are the major cause of early-onset familial Alzheimer's disease. In addition to APP, [gamma]-secretase substrates include Notch1 homologues, Notch ligands Delta and Jagged, and additional type I membrane proteins, raising concerns about mechanism-based toxicities that might arise as a consequence of inhibiting [gamma]-secretase. Notch signaling is involved in tumorigenesis as well as in determining the fates of neural and nonneural cells during development and in adults. Alterations in proteolysis of the Notch by [gamma]-secretase could be involved in the pathogenesis of AD. Inconsistently, several recent observations have indicated that enhanced Notch signaling and expression could be instrumental in neurodegeneration in AD. Therefore, detailed and precise study of Notch signaling in AD is important for elucidating diverse mechanisms of pathogenesis and potentially for treating and preventing Alzheimer's disease