the intension in this work is to investigate the effect of different bending manifold pipes on engine performance for different engine speed. Power, Torque, and BSFC were calculated and presented to show the effect of varying bending pipes angles on them for all cases considered. A special program used to carry out the calculations. A simulation model for 4-cylinders spark ignition engine with ...

An experimental and numerical investigation is performed into the power loss induced in grooved polymer optical fibers (POFs) subjected to combined bending and elongation deformations. The power loss is examined as a function of both the groove depth and the bend radius. An elastic-plastic three-dimensional finite element model is constructed to simulate the deformation in the grooved region of...

Microtubules (MTs) have been proposed to act mechanically as compressive struts that resist both actomyosin contractile forces and their own polymerization forces to mechanically stabilize cell shape. To identify the origin of MT bending, we directly observed MT bending and F-actin transport dynamics in the periphery of LLC-PK1 epithelial cells. We found that F-actin is nearly stationary in the...

DNA bending is important for the packaging of genetic material, regulation of gene expression and interaction of nucleic acids with proteins. Consequently, it is of considerable interest to quantify the energetic factors that must be overcome to induce bending of DNA, such as base stacking and phosphate-phosphate repulsions. In the present work, the electrostatic contribution of phosphate-phosp...

A model is proposed in which bending and wrapping of DNA around RNA polymerase causes untwisting of the DNA helix at the RNA polymerase catalytic center to stimulate strand separation prior to initiation. During elongation, DNA bending through the RNA polymerase active site is proposed to lower the energetic barrier to the advance of the transcription bubble. Recent experiments with mammalian R...

The weakly bending rod (WBR) model of double-stranded DNA (dsDNA) is adapted to analyze the internal dynamics of dsDNA as observed in electron paramagnetic resonance (EPR) measurements of the spin-lattice relaxation rate, R(1e), for spin probes rigidly attached to nucleic acid-bases. The WBR theory developed in this work models dsDNA base-pairs as diffusing rigid cylindrical discs connected by ...

Four laser scanning schemes for tube bending, including point-source circumferential scanning, pulsed line-source axial procession, and line-source axial scanning without and with water cooling are investigated in numerical simulation. The coupled thermomechanical model established using the finite element method is validated and applied to predict the bending deformation and help better unders...

Sharp bending of double-stranded DNA (dsDNA) plays an essential role in genome structure and function. However, the elastic limit of dsDNA bending remains controversial. Here, we measured the opening rates of small dsDNA loops with contour lengths ranging between 40 and 200 bp using single-molecule Fluorescence Resonance Energy Transfer. The relationship of loop lifetime to loop size revealed a...