scape bending disorder is the most important factor affecting postharvest loss of gerbera cut flowers. one of the ultimate reasons for gerbera stem bending is lignin, with deformation structural functions and defensive mechanisms. this postharvest experiment was conducted to evaluate the role of phenylalanine ammonia lyase (pal) and peroxidase (pod) enzymes activity in stem bending of two gerbe...

when very large floating structure) vlfs (is heavily loaded in the central portion, the difference deflection between its central section and its corners would increase. one cost effective solution for reducing the differential deflection is gill cell. gill cells are compartments in the vlfs that the buoyancy forces are eliminated at their locations. in this study, for examine the gill cells be...

Lipid interfaces, ranging from cell membranes to thin surfactant layers that stabilize lung alveoli, are integral to living systems. Such interfaces are often subjected to mechanical forces, and because of their membrane-like geometry, they can easily deform by bending into localized folds. In this work, we explore the role of small molecules (i.e., glycerol) on the mechanical stability of mode...

Voltage-gated sodium channels are members of a large family with similar pore structures. The mechanism of opening and closing is unknown, but structural studies suggest gating via bending of the inner pore helix at a glycine hinge. Here we provide functional evidence for this gating model for the bacterial sodium channel NaChBac. Mutation of glycine 219 to proline, which would strongly favor b...

Conical inclusions in a lipid bilayer generate an overall spontaneous curvature of the membrane that depends on concentration and geometry of the inclusions. Examples are integral and attached membrane proteins, viruses, and lipid domains. We propose an analytical model to study budding and vesiculation of the lipid bilayer membrane, which is based on the membrane bending energy and the transla...

BACKGROUND Surgery with pedicle screw instrumentation does not provide sufficient torsional stability. This leads to pseudoarthrosis, loosening of the pedicle screws, and, ultimately, implant failure. MATERIAL AND METHODS Functional spinal units from 18 deer were evaluated using a 6-axis material testing machine. As specimen models, we prepared an intact model, a damaged model, a cross-rod mode...

Four-roll bending process is usually used for manufacturing of seamed thick-walled and thin-walled cylinders. Due to complexity of this process, the analytical solution of plate bending in this process has not been developed completely. The existence of friction and multi-step processing makes it more difficult. Investigation of four-roll bending process using analytical and numerical methods i...

Elastic-plastic behavior of a beam made of functionally graded material is investigated in this work‎. ‎The beam is subjected to the constant axial and bending loads and the critical values of these loads for yield‎, ‎collapse and elastic-plastic conditions are obtained‎. ‎The variation of elastic modulus and yield strength through the height of the beam is determined with an exponential rule‎....

This paper investigates the hygrothermal effects on the failure mechanisms in bending of carbon fibre reinforced polymer (CFRP) composites. Accelerated diffusion testing was carried out by immersion at 50°C constant temperature and 70 bar hydrostatic pressure to study the effects of fresh or sea water diffusion into pre-preg CFRP laminates. Consequently the composite laminates were tested in be...

In this paper, a Paris law-based model is presented whereby crack propagation occurs under cyclic loading in air (fatigue) and in an aggressive environment (corrosion-fatigue) for the case of corner cracks (with a wide range of aspect ratios in the matter of the initial cracks) in finite-thickness plates of 316L austenitic stainless steel subjected to tension, bending, or combined (tension + be...