A numerical study of the complex flow structure in a compound meandering channel

[EN] In this study, we report large eddy simulations of turbulent flow in a periodic compound meandering channel for three different depth conditions: one in-bank and two overbank conditions. The flow configuration corresponds to the experiments of Shiono and Muto (1998). The predicted mean streamwise velocities, mean secondary motions, velocity fluctuations, turbulent kinetic energy as well as mean flood flow angle to meandering channel are in good agreement with the experimental measurements. We have analyzed the flow structure as a function of the inundation level, with particular emphasis on the development of the secondary motions due to the interaction between the main channel and the floodplain flow. Bed shear stresses have been also estimated in the simulations. Floodplain flow has a significant impact on the flow structure leading to significantly different bed shear stress patterns within the main meandering channel. The implications of these results for natural compound meandering channels are also discussed.Moncho Esteve, IJ.; García-Villalba, M.; MUTO Y.; SHIONO K.; Palau-Salvador, G. (2018). A numerical study of the complex flow structure in a compound meandering channel. Advances in Water Resources. 116:95-116. https://doi.org/10.1016/j.advwatres.2018.03.013S9511611

TRITERPENOID LUPAN DARI KULIT BATANG SONNERATIA ALBA (LYTHRACEAE)

Dua senyawa triterpenoid lupan, lupan-3b-ol (1) danlupeol (2) telah diisolasi dari kulit batang Sonneratiaalba (Lythraceae). Struktur kimia kedua senyawatersebut telah diidentifikasi berdasarkan data spektroskopidan perbandingan data spektra yang diperolehdari literatur. Senyawa 1 dan 2 menunjukkanaktivitas antibakteri terhadap bakteri Gram positifStaphylococcus aureus dan Streptococcus mutansdengan nilai MIC berturut-turut 94,1; 120; 35,2 dan22,6 mg/mL.Kata kunci: Antibakteri, lupan-3b-ol, lupeol, Sonneratiaalba, Lythraceae

Modeling of vegetated rivers for inbank and overbank flows

Model parameters such as friction factor and eddy viscosity in the Shiono & Knight method (SKM) are considered through experimental data obtained from a vegetated open channel. The experiment was conducted in a rectangular open channel with cylindrical rods as vegetation. Velocity, Reynolds stresses and boundary shear stress were measured with Acoustic Doppler Velocimetry (ADV) and a Preston tube re-spectively. Both friction factor and eddy viscosity were calculated using the measured data and found to be not constant in the shear layer generated by rods. The analytical solutions of SKM to predict velocity and boundary shear stress currently in use were based on the constant assumption of these parameters. In this pa-per a new analytical solution was derived by taking into a variation of these parameters account and was also verified with the experimental data. This solution was also applied to flow in compound channel with vegeta-tion. The new solution gives a good prediction of the lateral distribution of depth-averaged velocity and boundary shear stress in vegetated channels, and it predicts the boundary shear stress better than that of the original solution without considering the secondary flow term in particular

Kuersetin Dan Kuersetin-3-O-Glukosida Dari Kulit Batang Sonneratia Alba (Lythraceae)

Two flavonoid compounds, quercetin (1) and quercetin-3-O-glucoside (2) have been isolated from the bark of Sonneratia alba (Lythraceae). Chemical structure of both compounds were determined on the basis of spectroscopic data and comparison with those spectra data previously reported. Compound 1 and 2 exhibited antibacterial activity against Gram-positive bacteria, Staphylococcus aureus and Streptococcus mutans with MIC values of 51.2; 48.8; 72.5; dan 100.7 µg/mL respectively.DOI :http://dx.doi.org/10.15408/jkv.v0i0.315

Diagnostic accuracy of computed tomography-derived fractional flow reserve a systematic review

Importance Computed tomography–derived fractional flow reserve (FFR-CT) is a novel, noninvasive test for myocardial ischemia. Clinicians using FFR-CT must be able to interpret individual FFR-CT results to determine subsequent patient care. Objective To provide clinicians a means of interpreting individual FFR-CT results with respect to the range of invasive FFRs that this interpretation might likely represent. Evidence Review We performed a systematic review in accordance with guidelines from the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. A systematic search of MEDLINE (January 1, 2011, to 2016, week 2) and EMBASE (January 1, 2011, to 2016, week 2) was performed for studies assessing the diagnostic accuracy of FFR-CT. Title words used were computed tomography or computed tomographic and fractional flow reserve or FFR. Results were limited to publications in peer-reviewed journals. Duplicate studies and abstracts from scientific meetings were removed. All of the retrieved studies, including references, were reviewed. Findings There were 908 vessels from 536 patients in 5 studies included in the analysis. A total of 365 (68.1%) were male, and the mean (SD) age was 63.2 (9.5) years. The overall per-vessel diagnostic accuracy of FFR-CT was 81.9% (95% CI, 79.4%-84.4%). For vessels with FFR-CT values below 0.60, 0.60 to 0.70, 0.70 to 0.80, 0.80 to 0.90, and above 0.90, diagnostic accuracy of FFR-CT was 86.4% (95% CI, 78.0%-94.0%), 74.7% (95% CI, 71.9%-77.5%), 46.1% (95% CI, 42.9%-49.3%), 87.3% (95% CI, 85.1%-89.5%), and 97.9% (95% CI, 97.9%-98.8%), respectively. The 82% (overall) diagnostic accuracy threshold was met for FFR-CT values lower than 0.63 or above 0.83. More stringent 95% and 98% diagnostic accuracy thresholds were met for FFR-CT values lower than 0.53 or above 0.93 and lower than 0.47 or above 0.99, respectively. Conclusions and Relevance The diagnostic accuracy of FFR-CT varies markedly across the spectrum of disease. This analysis allows clinicians to interpret the diagnostic accuracy of individual FFR-CT results. In combination with patient-specific factors, clinicians can use FFR-CT to judge when the cost and risk of an invasive angiogram may safely be avoided

A TRITERPENOID COMPOUND FROM THE STEMBARK OF Aglaia argentea (MELIACEAE)

Senyawa triterpenoid, 3-epicabraleahydroxylactone (1) telah diisolasi dari ekstrak n-heksana kulit batang Aglaia argentea. Struktur kimia senyawa 1 diidentifikasikan berdasarkan data-data spektroskopi dan perbandingan data spektra yang diperoleh sebelumnya. Senyawa triterpenoid, 3-epikabrraleahidroksilakton (1) dilaporkan pada tumbuhan ini untuk pertama kali

Intracellular Trafficking of the Amyloid β-Protein Precursor (APP) Regulated by Novel Function of X11-Like

Background: Amyloid beta (A beta), a causative peptide of Alzheimer's disease, is generated by intracellular metabolism of amyloid beta-protein precursor (APP). In general, mature APP (mAPP, N- and O-glycosylated form) is subject to successive cleavages by alpha- or beta-, and gamma-secretases in the late protein secretory pathway and/or at plasma membrane, while immature APP (imAPP, N-glycosylated form) locates in the early secretory pathway such as endoplasmic reticulum or cis-Golgi, in which imAPP is not subject to metabolic cleavages. X11-like (X11L) is a neural adaptor protein composed of a phosphotyrosine-binding (PTB) and two C-terminal PDZ domains. X11L suppresses amyloidogenic cleavage of mAPP by direct binding of X11L through its PTB domain, thereby generation of A beta lowers. X11L expresses another function in the regulation of intracellular APP trafficking. Methodology: In order to analyze novel function of X11L in intracellular trafficking of APP, we performed a functional dissection of X11L. Using cells expressing various domain-deleted X11L mutants, intracellular APP trafficking was examined along with analysis of APP metabolism including maturation (O-glycosylation), processing and localization of APP. Conclusions: X11L accumulates imAPP into the early secretory pathway by mediation of its C-terminal PDZ domains, without being bound to imAPP directly. With this novel function, X11L suppresses overall APP metabolism and results in further suppression of Ab generation. Interestingly some of the accumulated imAPP in the early secretory pathway are likely to appear on plasma membrane by unidentified mechanism. Trafficking of imAPP to plasma membrane is observed in other X11 family proteins, X11 and X11L2, but not in other APP-binding partners such as FE65 and JIP1. It is herein clear that respective functional domains of X11L regulate APP metabolism at multiple steps in intracellular protein secretory pathways