Airway and bladder smooth muscles are known to undergo length adaptation under sustained contraction. This adaptation process entails a remodelling of the intracellular actin and myosin filaments which shifts the peak of the active force-length curve towards the current length. Smooth muscles are therefore able to generate the maximum force over a wide range of lengths. In contrast, length adap...

The differences in angulation and length observed for the fibers of anatomical muscles may reflect two distinct mechanical requirements: arrangement for pinnation, reflecting an increase in physiological cross-section and arrangement for equivalent placement of sarcomeres, possibly associated with coordination. The observed differences in fiber angulation and length have different effects upon ...

To assess the extent to which the power output of a synchronous insect flight muscle is maximized during flight, we compared the maximum potential power output of the mesothoracic dorsolongitudinal (dl1) muscles of Manduca sexta to their power output in vivo. Holding temperature and cycle frequency constant at 36 degrees C and 25 Hz, respectively, we varied the phase of activation, mean length ...

Zebrafish muscles were examined at an early developmental stage (larvae 5-7 d). Using aluminum clips, preparations (approximately 1.5 mm length, 150 microm diameter) were mounted for force registration and small angle x-ray diffraction. Sarcomeres were oriented mainly in parallel with the preparation long axis. Electrical stimulation elicited fast and reproducible single twitch contractions. Le...

SYNOPSIS. The function of muscles used to generate force economically and facilitate elastic energy savings in their tendons is compared with muscles that function to produce mechanical power. The underlying architectural design of the muscle and its tendon (if present) dictate much of their functional capacity and role in animal locomotion. Using methods that allow direct recordings of muscle ...

We describe the design, construction, and operation of a novel continuous backbone “continuum” robot. Inspired by biological trunks and tentacles, the robot is actuated by the pneumatic muscles which form its structure. In contrast to previous designs, the actuators are contractor muscles, which decrease in length as pressure is increased. This choice of actuator results in novel and improved p...

Crossbred steers (n = 30) were used to explore and compare tenderness improvements in beef round and sirloin muscles resulting from various methods of prerigor skeletal separations. Animals were slaughtered according to industry procedures, and at 60 min postmortem one of six treatments was applied to each side: A) control, B) saw pelvis at the sirloin-round junction, C) separate the pelvic-fem...

The variation in thin filament length was investigated in slow and fast muscle from adult and neonatal rats. Soleus (slow) muscle from adult, 3-, 7-, and 9-d-old rats, and extensor digitorum longus (EDL; fast) muscle from adult rats were serially cross-sectioned. The number of thin filaments per 0.06 microns2 (TF#) was counted for individual myofibrils followed from the H zone of one sarcomere,...

 Concentration of heavy and toxic metals Cu, Zn, Cd, Pb and Hg were determined in liver and muscles of Rutilus frisii kutum and their relationships with growth parameters (length, age, condition factor) and hepatosomatic index were examined. Thirty-six fish samples were collected from February through March 2009 caught by beach seine in the southwest parts of the Caspian Sea. Atomic absorption ...

PURPOSE To quantify the gain in muscle mobility with progressive release of surrounding connective-tissue structures and to compare this property with the known architecture of each muscle. METHODS Each of 5 different muscle tendon units (extensor carpi radialis brevis, extensor carpi radialis longus, flexor carpi ulnaris, flexor digitorum superficialis, pronator teres) was released from its ...