RNA secondary structures of increasing complexity are probed combining single molecule stretching experiments and stochastic unfolding/refolding simulations. We find that force-induced unfolding pathways cannot usually be interpreted by solely invoking successive openings of native helices. Indeed, typical force-extension responses of complex RNA molecules are largely shaped by stretching-induc...

In this research, softening and ratcheting behaviors of Ck20 alloy steel cylindrical shells were studied under displacement-control and force-control cyclic axial loading and the behavior of hysteresis curves of specimens was also investigated. Experimental tests were performed by a servo-hydraulic INSTRON 8802 machine. The mechanical properties of specimens were determined according to ASTM E8...

In this paper, a new model for electroadhesion between two surface-insulated plates under DC electric field is presented and control of dynamic responses of electroadhesion force is discussed. Under DC electric field, even if the voltage difference between the plates is constant, electroadhesion force increases or decreases over time depending on the insulating materials. The increase had been ...

BACKGROUND The purpose of the present study was to examine the in vitro responses of ERM cells under the combination of centrifugal and compression forces, in terms of their expression of HSP70 mRNA. METHODS The ERM cells were positive for CK19 indicating that they were derived from the odontogenic epithelium. Cultured ERM cells were applied centrifugal force and compressing force at one to t...

Here we demonstrate the implementation of a single-molecule force clamp adapted for use with an atomic force microscope. We show that under force-clamp conditions, an engineered titin protein elongates in steps because of the unfolding of its modules and that the waiting times to unfold are exponentially distributed. Force-clamp measurements directly measure the force dependence of the unfoldin...

Force sensors are at the heart of different technologies such as atomic force microscopy or inertial sensing. These sensors often rely on the measurement of the displacement amplitude of mechanical oscillators under applied force. The best sensitivity is typically achieved when the force is alternating at the mechanical resonance frequency of the oscillator, thus increasing its response by the ...

Formation of the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex provides mechanical thrust for membrane fusion, but its molecular mechanism is still unclear. Here using magnetic tweezers, we observe mechanical responses of a single neuronal SNARE complex under constant pulling force. Single SNARE complexes may be unzipped with 34 pN force. When rezipping i...