2,617 research outputs found
A DRAINAGE SYSTEM FOR MITIGATING MOISTURE DAMAGE TO BRIDGE DECK PAVEMENTS
This study presents the development of a new drainage system that can quickly drain water that has penetrated into bridge deck pavements. The new drainage system is expected to significantly reduce potholes that typically lead to premature failure of pavements. This system can be established by applying a thin drainage layer between the waterproofing layer and top wearing course. The most important factors for this system are to meet satisfactory performance of the waterproofing layer and to develop appropriate construction technique for the thin drainage layer. The drainage layer was formulated with porous asphalt mixtures designed for the max aggregate size of 10 mm, and was validated through various physical and mechanical laboratory tests to confirm its performance characteristics. For the waterproofing layer, methyl methacrylate (MMA) ā type material was introduced, and a series of mechanical tests were performed to estimate the applicability of the MMA material for waterproofing. It was observed from the tests that the MMA material satisfied all specification requirements. In addition, to evaluate the field performance of the new drainage system, a field study was conducted on a real bridge. Field performance observations on both the waterproofing and pavement materials indicated that the new drainage system performs much better than traditional methods in draining water that has penetrated into pavement layers
Feature Reduction for Product Recommendation in Internet Shopping Malls
One of the widely used methods for product recommendation in Internet shopping malls is matching product features against customersā profiles. In this method, it is very important to choose suitable set of features for recommendation efficiency and performance, which has, however, not been rigorously researched so far. In this paper, we build a data set collected from a virtual Internet shopping experiment and adapt and apply feature reduction techniques from pattern matching and information retrieval fields to the data to analyze recommendation performance. The analysis shows that the application of SVD (Singular Value Decomposition) can be the best among the applied methods for recommendation performance
Jamming transition in a highly dense granular system under vertical vibration
The dynamics of the jamming transition in a three-dimensional granular system
under vertical vibration is studied using diffusing-wave spectroscopy. When the
maximum acceleration of the external vibration is large, the granular system
behaves like a fluid, with the dynamic correlation function G(t) relaxing
rapidly. As the acceleration of vibration approaches the gravitational
acceleration g, the relaxation of G(t) slows down dramatically, and eventually
stops. Thus the system undergoes a phase transition and behaves like a solid.
Near the transition point, we find that the structural relaxation shows a
stretched exponential behavior. This behavior is analogous to the behavior of
supercooled liquids close to the glass transition.Comment: 5 pages, 5 figures, accepted by Phys. Rev.
Assessment of Animal Palatability for Domestic Developed Italian Ryegrass \u3cem\u3eLolium multiflorum\u3c/em\u3e Lam. in South Korea
About 5.6 million tons of forage were consumed in ruminant animals in Korea. But, most of them were supplied in rice straw (2 million ton) and more than one million ton of forage was imported from oversea. As a matter of fact, the self-sufficiency rate of high quality forage was 44 % (2.5 million ton). The research institute had started breeding programs of forage varieties (orchardgrass, Tall fescue and Italian ryegrass), Their remarkable breeding program resulted in release of a synthetic species Italian ryegrass (Lolium multiflorum Lam.) which was more cold-tolerant, much higher yielding than introduced varieties and more adapted in paddy field. Most varieties had focused in evaluation of chemical analysis and productivities of dry matter, however assessment of palatability for ruminant was not conducted. For this reason, this report examines the assessment of animal palatability for domestic developed Italian ryegrass in Korea
Multimodality cardiovascular imaging in pulmonary embolism
Acute pulmonary embolism (APE) is one of the leading causes of cardiovascular (CV) morbidity andmortality. To select appropriate therapeutic strategy and/or to minimize the mortality and morbidity,rapid and correct identification of life-threatening APE is very important. Also, right ventricular (RV)failure usually precedes acute hemodynamic compromise or death, and thus the identification of RVfailure is another important step in risk stratification or treatment of APE. With advances in diagnosisand treatment, the prognosis of APE has been dramatically improving in most cases, but inadequatetherapy or recurrent episodes of pulmonary embolism (PE) may result in negative outcomes or, so called,chronic thromboembolic pulmonary hypertension (CTEPH). CTEPH is a condition characterized byremaining chronic thromboembolic material in the pulmonary vasculature and subsequent chronicpulmonary hypertension.Various imaging modalities include chest computed tomography pulmonary angiography (CTPA),echocardiography, magnetic resonance imaging, and nuclear imaging and each are used for the assessmentof varying status of PE. Assessment of thromboembolic burden by chest CTPA is the first step inthe diagnosis of PE. Hemodynamic assessment can be achieved by echocardiography and also by chestCTPA. Nuclear imaging is useful in discriminating CTEPH from APE.Better perspectives on diagnosis, risk stratification and decision making in PE can be provided bycombining multimodality CV imaging. Here, the advantages or pitfalls of each imaging modality indiagnosis, risk stratification, or management of PE will be discussed
Ruthenium anchored on carbon nanotube electrocatalyst for hydrogen production with enhanced Faradaic efficiency
Developing efficient and stable electrocatalysts is crucial for the electrochemical production of pure and clean hydrogen. For practical applications, an economical and facile method of producing catalysts for the hydrogen evolution reaction (HER) is essential. Here, we report ruthenium (Ru) nanoparticles uniformly deposited on multi-walled carbon nanotubes (MWCNTs) as an efficient HER catalyst. The catalyst exhibits the small overpotentials of 13 and 17 mV at a current density of 10 mA cm(-2) in 0.5M aq. H2SO4 and 1.0M aq. KOH, respectively, surpassing the commercial Pt/C (16 mV and 33 mV). Moreover, the catalyst has excellent stability in both media, showing almost "zeroloss" during cycling. In a real device, the catalyst produces 15.4% more hydrogen per power consumed, and shows a higher Faradaic efficiency (92.28%) than the benchmark Pt/C (85.97%). Density functional theory calculations suggest that Ru-C bonding is the most plausible active site for the HER
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Altered expression of norepinephrine transporter and norepinephrine in human placenta cause pre-eclampsia through regulated trophoblast invasion
Objective: We investigated the norepinephrine transporter (NET) expression in normal and pre-eclamptic placentas and analyzed the invasion activity of trophoblastic cells based on norepinephrine (NE)-NET regulation. Methods: NET and NE expression levels were examined by western blot and enzyme-linked immunosorbent assay, respectively. Trophoblast invasion activity, depending on NE-NET regulation, was determined by NET-small interfering RNA (siRNA) and NET transfection into the human extravillous trophoblast cells with or without NE treatment and invasion rates were analyzed by zymography and an invasion assay. Results: NET mRNA was expressed at a low level in pre-eclamptic placentas compared with normal placentas and NE concentration in maternal plasma increased significantly in pre-eclamptic women compared to normal pregnant women (p<0.05). NET gene upregulation and NE treatment stimulated trophoblast cell invasion up to 2.5-fold (p<0.05) by stimulating matrix metalloproteinase-9 activity via the phosphoinositol-3-kinase/AKT signaling pathway, whereas NET-siRNA with NE treatment reduced invasion rates. Conclusion: NET expression is reduced by inadequate regulation of NE levels during placental development. This suggests that a complementary balance between NET and NE regulates trophoblast cell invasion activities during placental development
The Effect of Sirolimus Based Regimen On Immune Reconstitution After Allogeneic Stem Cell Transplantation
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