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Particle‐mediated or “gene gun” technology has been developed as a nonviral method for gene transfer into various mammalian tissues. Gene delivery is achieved by physical force that launches DNA‐coated gold particles towards targeted cells. Consider a gold particle that is launched at an angle of 25° to the horizontal with an initial resultant velocity of 25 m/sec. Find both the vertical and horizontal components of the initial velocity vector. Clearly label your answer for the vertical and horizontal components in the text box below.

At the longest muscle lengths, most of the force measured in the muscle is due to crossbridge connection.

The dust storms that devastated the plains resulted from all of the following EXCEPT …

Given angle α = 55°, opposite side = 4 m in a right triangle, find the hypotenuse and adjacent side lengths.

The muscle torque is greater than the load (resistance) torque during a concentric contraction.

Consider the leg positions of Gymnast A and Gymnast B. First, state the anatomical plane you are viewing the gymnasts in. Second, state which hip motion is depicted when going from A to B. Third, describe the active and passive insufficiencies that Gymnast A must overcome to go from the posture in A to the posture in B.

The larger wheels on a wheelchair are 0.62 m in diameter. If these wheels take 0.5 seconds to rotate one full revolution, what is the tangential velocity of the wheelchair?

During the Great Depression, the federal government began to deport …

What New Deal agency put young, single men to work planting trees, building parks and fighting soil erosion?

A person (75 kg) walks straight ahead at a uniform speed of 2 steps (one gait cycle) per second. The above image shows the hip joint angle over the course of the gait cycle. Draw 4 separate free body diagrams on your scratch paper of the forces acting on the person as a whole (neglecting air resistance) from a sagittal view at: A) 30% of the gait cycle. (Only the right leg is in contact with the ground, i.e., single-stance. Note that hip angle is close to zero, so you can assume the person is standing fully upright). B) the same time in the gait cycle, but while carrying a cube-shaped box (mass 20 kg) that is 20 cm long and touches his abdomen. The horizontal distance between the center of his lumbar-sacral (low-back) disc to the front of his abdomen is 20 cm. The center of the disc represents the axis of rotation for trunk flexion/extension. C) the same time in the gait cycle, but while holding a different cube-shaped box (mass 25 kg) that is 15 cm long and also touches his abdomen. D) the same time in the gait cycle, but while holding yet a different cube-shaped box (mass 5 kg) which is 40 cm long, also touching his abdomen. You will upload these free body diagrams at the end once you have submitted your exam. Please make sure they are clearly labeled. (Note: you do not need to write anything in the text box below. This is just here in case you need to write any contextual information down to help us clarify your hand-drawn answer).