Arm

In human anatomy, the arm is the upper limb of the body, comprising regions between the glenohumeral joint (shoulder joint) and the elbow joint. In common usage the arm extends to the hand. It can be divided into the upper arm (brachium), the forearm (antebrachium), and the hand (manus). Anatomically the shoulder girdle with bones and corresponding muscles is by definition a part of the arm. The Latin term brachium may refer to both the arm as a whole or to the upper arm on its own.

Anatomy

Bones

The humerus is one of the three long bones of the arm. It joins with the scapula at the shoulder joint and with the other long bones of the arm, the ulna and radius at the elbow joint. The elbow is the hinge joint between the end of the humerus and the ends of the radius and ulna. The humerus cannot be broken easily. Its strength allows it to handle loading up to 300 pounds (140 kg).

Muscles

The arm is divided by a fascial layer (known as lateral and medial intermuscular septa) separating the muscles into two osteofascial compartments: the anterior and the posterior compartments of the arm. The fascia merges with the periosteum (outer bone layer) of the humerus. The compartments contain muscles which are innervated by the same nerve and perform the same action.

Tor (anonymity network)

Tor is free software for enabling anonymous communication. The name is an acronym derived from the original software project name The Onion Router, however the correct spelling is "Tor", capitalizing only the first letter. Tor directs Internet traffic through a free, worldwide, volunteer network consisting of more than seven thousand relays to conceal a user's location and usage from anyone conducting network surveillance or traffic analysis. Using Tor makes it more difficult for Internet activity to be traced back to the user: this includes "visits to Web sites, online posts, instant messages, and other communication forms". Tor's use is intended to protect the personal privacy of users, as well as their freedom and ability to conduct confidential communication by keeping their Internet activities from being monitored.

Onion routing is implemented by encryption in the application layer of a communication protocol stack, nested like the layers of an onion. Tor encrypts the data, including the destination IP address, multiple times and sends it through a virtual circuit comprising successive, randomly selected Tor relays. Each relay decrypts a layer of encryption to reveal only the next relay in the circuit in order to pass the remaining encrypted data on to it. The final relay decrypts the innermost layer of encryption and sends the original data to its destination without revealing, or even knowing, the source IP address. Because the routing of the communication is partly concealed at every hop in the Tor circuit, this method eliminates any single point at which the communicating peers can be determined through network surveillance that relies upon knowing its source and destination.

Arm (disambiguation)

An arm is an upper limb of the body.

Arm or ARM may also refer to:

Geography

Science and medicine

Technology

Computing

ARM (novella)

ARM is a science fiction novella by American author Larry Niven. Set in the Known Space cycle, it is the third of five Gil Hamilton detective stories.

Hamilton is called to the scene of a murder. The victim is Dr. Raymond Sinclair, a brilliant scientist who has invented a mysterious device that creates a bubble of accelerated time. The murder scene is a locked apartment at the top of a high-rise, where the prime suspect is a beautiful young woman whom Gil refuses to believe is the killer.

One of the themes running throughout the story, and in fact a vital element in the solution of the mystery, is the loss of an arm. Gil himself lost an arm and had a new one grafted on, using parts from an organ bank which is supplied by the bodies of criminals and "corpsicles", people who underwent cryogenic suspension. At the scene of the crime, a beautiful young woman is discovered unconscious in an "autodoc" (a device for fixing minor injuries or preserving life until help arrives) recovering from the loss of one of her arms. Another character in the story also lost an arm previously, but regards grafts as immoral and wears an advanced prosthetic arm instead. The "accelerated time bubble" has the effect of amputating the arm of anyone who reaches into it, since the arm's metabolism speeds up to the point where the rest of the body cannot supply it with blood.