the base isolation systems are among the passive control devices that have been used over the last three decades to limit the seismic-induced response of structures. in this regard, the uniform building code provisions (ubc) has incorporated a special section for the seismic design of base isolated structures since its 1991 edition. due to the importance of the behavior of these structures unde...

Chromosomes, DNA, and single fluorescent molecules are studied using an aperture-type near-field scanning optical microscope with tuning fork shear force feedback. Fluorescence in situ hybridization labels on repetitive and single copy probes on human metaphase chromosomes are imaged with a width of 80 nm, allowing their localisation with nanometer accuracy, in direct correlation with the simul...

Scanning ion conductance microscopy (SICM) is an imaging technique, measuring conductance through a nanometer-sized pipette tip opening that is brought close to a sample surface submerged in electrolyte ­solution. In combination with an integrated shear force distance control, the local ion conductance can be measured independently of and simultaneously with topography. The design of a shear-fo...

Elastic deformation on the surfaces of molecular crystals can be imaged using a variant of lateral force microscopy in which the tip is scanned parallel to the cantilever axis. The shear force transverse to this direction has a distinctly different origin than the friction force as determined by the tip velocity and temperature dependence of the cantilever torque. An elastic deformation model f...

The three-dimensional tertiary structure of human von Willebrand Factor (vWF) on a hydrophobic surface under aqueous conditions and different shear stress regimes was studied by atomic force microscopy (AFM). vWF was imaged by AFM at molecular level resolution under negligible shear stress, under a local applied shear force (7.4 to 19 nN) using the AFM probe in contact mode scanning, and after ...

We analyze the shear strength and microstructure of binary granular mixtures consisting of disks and elongated particles by varying systematically both the mixture ratio and degree of homogeneity (from homogeneous to fully segregated). The contact dynamics method is used for numerical simulations with rigid particles interacting by frictional contacts. A counterintuitive finding of this work is...

Thirteen Brahman x Shorthorn steers approximately 18 months of age with a mean carcass weight of 190 (a 7.1) kg and a mean fat thickness of 5.8 (+ 1.9) mm at the rump P8 site were subjected to 4 postslaughter treatments. These were: no electrical stimulation or ageing (NIL); electrical stimulation, no ageing (ES); no electrical stimulation, ageing (AGED); electrical stimulation and ageing(ESAGE...

The current experiment was conducted to evaluate the on-line application of visible and near-infrared spectroscopy (VISNIR) to US Select carcasses during commercial beef carcass grading procedures to predict tenderness of longissimus steaks after 14 days of refrigerated storage. A regression model was calibrated using 146 carcasses and tested against an additional 146 carcasses. Carcasses were ...

Surface adhesion of bacteria generally occurs in the presence of shear stress, and the lifetime of receptor bonds is expected to be shortened in the presence of external force. However, by using Escherichia coli expressing the lectin-like adhesin FimH and guinea pig erythrocytes in flow chamber experiments, we show that bacterial attachment to target cells switches from loose to firm upon a 10-...

The ability of gecko lizards to adhere to a vertical solid surface comes from their remarkable feet with aligned microscopic elastic hairs. By using carbon nanotube arrays that are dominated by a straight body segment but with curly entangled top, we have created gecko-foot-mimetic dry adhesives that show macroscopic adhesive forces of approximately 100 newtons per square centimeter, almost 10 ...