4 research outputs found
Alternative design of square-rooting measuring device in open channel - Closure
This paper is concerned with the design of a practical quadratic weir of a simple geometrical shape, having an inward trapezoidal weir of crest width 2 w and vertex angle 2theta, over which a rectangular weir is fitted at an optimum depth p= 0.95 d ( d= overall depth of the inward trapezoidal weir) above the weir crest. It is shown that the flow through this weir is proportional to the square root of head h measured from the datum or reference plane situated at 0.5 d above the crest, for all flows in the range of p<=h<= 2.95 p within a maximum error deviation of ±2% from the exact theoretical discharge. A numerical optimization procedure is developed to obtain the optimum parameters of the weir yielding a maximum quadratic head-discharge relationship. Experiments with two different weirs show excellent agreement with the theory by giving a constant average coefficient of discharge. The application of the weir in the proportionate method of flow measurement using a bypass in an open channel and as a sensitive flow-measuring device in irrigation canals are highlighted
Geometrically Simple Logarithmic Weir
This paper discusses the design and experimental verification of a geometrically simple logarithmic weir. The weir consists of an inward trapezoidal weir of slope 1 horizontal to n vertical, or 1 in n, over two sectors of a circle of radius R and depth d, separated by a distance 2t. The weir parameters are optimized using a numerical optimization algorithm. The discharge through this weir is proportional to the logarithm of head measured above a fixed reference plane for all heads in the range 0.23R less than or equal to h less than or equal to 3.65R within a maximum deviation of +/-2% from the theoretical discharge. Experiments with two weirs show excellent agreement with the theory by giving a constant average coefficient of discharge of 0.62. The application of this weir to the field of irrigation, environmental, and chemical engineering is highlighted
Phosphotyrosine profiling of curcumin-induced signaling
BACKGROUND: Curcumin, derived from the rhizome Curcuma longa, is a natural anti-cancer agent and has been shown to inhibit proliferation and survival of tumor cells. Although the anti-cancer effects of curcumin are well established, detailed understanding of the signaling pathways altered by curcumin is still lacking. In this study, we carried out SILAC-based quantitative proteomic analysis of a HNSCC cell line (CAL 27) to investigate tyrosine signaling in response to curcumin. RESULTS: Using high resolution Orbitrap Fusion Tribrid Fourier transform mass spectrometer, we identified 627 phosphotyrosine sites mapping to 359 proteins. We observed alterations in the level of phosphorylation of 304 sites corresponding to 197 proteins upon curcumin treatment. We report here for the first time, curcumin-induced alterations in the phosphorylation of several kinases including TNK2, FRK, AXL, MAPK12 and phosphatases such as PTPN6, PTPRK, and INPPL1 among others. Pathway analysis revealed that the proteins differentially phosphorylated in response to curcumin are known to be involved in focal adhesion kinase signaling and actin cytoskeleton reorganization. CONCLUSIONS: The study indicates that curcumin may regulate cellular processes such as proliferation and migration through perturbation of the focal adhesion kinase pathway. This is the first quantitative phosphoproteomics-based study demonstrating the signaling events that are altered in response to curcumin. Considering the importance of curcumin as an anti-cancer agent, this study will significantly improve the current knowledge of curcumin-mediated signaling in cancer. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12014-016-9114-0) contains supplementary material, which is available to authorized users