Oncology & Cancer

USPSTF advises meds to reduce risk for primary breast cancer

The U.S. Preventive Services Task Force (USPSTF) recommends that clinicians offer risk-reducing medications to women at increased risk for breast cancer and at low risk for adverse medication effects. These recommendations ...

Medical research

Mechanical forces impact immune response in the lungs

When the body is fending off an infection, there are changes in temperature, pH balance, and metabolism. Yale researchers wondered if yet other factors might come into play, and in a recent study, confirmed that mechanical ...

Immunology

It's Fab! A hidden touch of antibody

In our immune system, antibodies recognize viruses, bacteria and even cancer cells through their Fab arms, initiating recruitment of leucocytes for the destruction of these invaders. The recruitment is mediated by receptors ...

Diseases, Conditions, Syndromes

3-D miniature livers lead the way to patient-specific drug discovery

The human liver is a vital organ involved in multiple functions. Because susceptibility to liver diseases is highly variable among patients, researchers from Tokyo Medical and Dental University (TMDU) and Cincinnati Children's ...

Medical research

Mechanical forces control cell fate during brain formation

A new study coordinated by the Research Group in Developmental Biology at UPF shows that during the embryonic development of the brain, the cells that are between adjacent segments detect the mechanical forces generated during ...

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Force

In physics, a force is any influence that causes an object to undergo a change in speed, a change in direction, or a change in shape. In other words, a force is that which can cause an object with mass to change its velocity (which includes to begin moving from a state of rest), i.e., to accelerate, or which can cause a flexible object to deform. Force can also be described by intuitive concepts such as a push or pull. A force has both magnitude and direction, making it a vector quantity. Newton's second law, F=ma, was originally formulated in slightly different, but equivalent terms: the original version states that the net force acting upon an object is equal to the rate at which its momentum changes.

Related concepts to force include: thrust, which increases the velocity of an object; drag, which decreases the velocity of an object; and torque which produces changes in rotational speed of an object. Forces which do not act uniformly on all parts of a body will also cause mechanical stresses, a technical term for influences which cause deformation of matter. While mechanical stress can remain embedded in a solid object, gradually deforming it, mechanical stress in a fluid determines changes in its pressure and volume.

This text uses material from Wikipedia, licensed under CC BY-SA