Diseases, Conditions, Syndromes

mRNA vaccine yields full protection against malaria in mice

Scientists from the Walter Reed Army Institute of Research and Naval Medical Research Center partnered with researchers at the University of Pennsylvania and Acuitas Therapeutics to develop a novel vaccine based on mRNA technology ...

Oncology & Cancer

Lung cancer: It is about more than smoking

World Cancer Day is February 4 and that makes this the ideal time to talk about lung cancer and smoking. Internationally, lung cancer is the most common cause of cancer deaths and the World Health Organization estimates that ...

Oncology & Cancer

Cancer cells 'talk' to their environment, and it talks back

Interactions between an animal cell and its environment, a fibrous network called the extracellular matrix, play a critical role in cell function, including growth and migration. But less understood is the mechanical force ...

Neuroscience

Brain activity predicts the force of your actions

Researchers have found a link between the activity in nerve clusters in the brain and the amount of force generated in a physical action, opening the way for the development of better devices to assist paralysed patients.

Health

Some breastfeeding advice worth ditching: US task force

A review of scientific evidence on breastfeeding out Tuesday found that some long-held advice is worth ditching, including that babies should avoid pacifiers and moms should breastfeed exclusively in the first days after ...

Oncology & Cancer

Q and A: Polyps are possible culprits in colon cancer

DEAR MAYO CLINIC: I'm 46 and had my first colonoscopy last month. The doctor said everything looked good, although he removed a few polyps. Can you explain what a colon polyp is and if should I be concerned?

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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