We analyze stability of a thin inextensible elastic rod which has non-vanishing spontaneous generalized torsions in its stress-free state. Two classical problems are studied, both involving spontaneously twisted rods: a rectilinear rod compressed by axial forces, and a planar circular ring subjected to uniform radial pressure on its outer perimeter. It is demonstrated that while spontaneous twi...

The effect of pre-impact waves on the coefficient restitution (COR) in longitudinal impact a uniform elastic rod linear or bilinear inelastic spring supported by fix rigid wall is studied. models may represent quasi-static response of, e.g., small cylinder bit-rock interaction percussive drilling. accelerated to its momentum either force relatively short duration which generates significant (pr...

In the process of heat transfer by conduction, besides quantities in form surface area, length or thickness rod, and temperature difference between ends rod value thermal conductivity, other factors also affect rate to one which is environmental factors. As long as flows from high low temperature, decrease not uniform at any time interval. This a sign influence ambient for each part material. T...

From the Smith-Kettlewell Institute of Visual Sciences, Pacific Medical Center. This investigation was supported by Research Career Program Award No. K3 NB-14,094 from the National Institute of Neurological Diseases and Blindness; Public Health Service Program Project Research Grant No. NB-06038, and General Research Support Grant No. S SOI FR-0S566. bearing surface was fashioned from a 1-mm-wi...

PURPOSE To obtain and analyze scotopic increment threshold functions to test the hypothesis that rod photoreceptor immaturity accounts for the elevation of infants' over controls' dark-adapted thresholds and elevation of parafoveal over peripheral thresholds in infants. METHODS Using a preferential looking method, thresholds for detection of 2(o), 50 msec, blue stimuli presented 10(o) (parafo...

We present a hybrid fluid-particle algorithm to simulate flow and transport of DNA-laden fluids in microdevices. Relevant length scales in microfluidic systems range from characteristic channel sizes of millimeters to micron scale geometric variation (e.g., post arrays) to 10 nanometers for the length of a single rod in a bead-rod polymer representation of a biological material such as DNA. The...

The lessons learned from p-octiphenyl beta-barrel pores are applied to the rational design of synthetic multifunctional pore 1 that is unstable but inert, two characteristics proposed to be ideal for practical applications. Nonlinear dependence on monomer concentration provided direct evidence that pore 1 is tetrameric (n = 4.0), unstable, and "invisible," i.e., incompatible with structural stu...

Pharmacotherapy treatment for alcoholism is limited by poor compliance, adverse effects, and fluctuating drug levels after bolus administration. A long-term delivery system would improve upon these limitations. The current study describes the characterization of a sustained release implant containing nalmefene, an opioid antagonist, for treatment of alcoholism. Nalmefene was blended with ethyle...

The rapid development of single molecule experimental techniques in the last two decades has made it possible to accurately measure the force-extension response as well as the transverse fluctuations of individual rod-like macromolecules. This information is used in conjunction with a statistical mechanical model based on the treatment of the molecule as a fluctuating elastic rod to extract its...