Robots that can sort recycling

Every year trash companies sift through an estimated 68 million tons of recycling, which is the weight equivalent of more than 30 million cars.

Researchers prove Leonardo Da Vinci was ambidextrous

Researchers at the Uffizi Gallery in Florence have proved what was suspected for a long time: that Renaissance genius Leonardo Da Vinci was able to write, draw and paint with both hands.

New aerodynamic insights could change the para-cycling podiums

Participants in Para-cycling races – cycling with a disability – would do well to study Paul Mannion's Ph.D. research. At Eindhoven University of Technology and National University of Ireland Galway he has been investigating ...

Hands spread flame retardants, plasticizers throughout homes

Hundreds of everyday items, from furniture to cell phones to floor wax, contain organophosphate ester (OPE) flame retardants and plasticizers. Some of these semi-volatile compounds make their way into the air, onto surfaces ...

Tackling India's e-waste recycling crisis

India's share of the world's massive e-waste problem has seen unskilled recyclers exposing themselves to dangerous processes. Jeevesh Kumar is working to delete the recycling danger, and reboot the benefits.

Newly discovered design rules lead to better fuel cell catalyst

To create better batteries and fuel cells, scientists must make oxygen molecules gain and lose electrons efficiently. The reactions are frustratingly sluggish. Speeding the reactions requires heat and platinum, which are ...

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Hand

A hand (med./lat.: manus, pl. manūs) is a prehensile, multi-fingered extremity located at the end of an arm or forelimb of primates such as humans, chimpanzees, monkeys, and lemurs. A few other vertebrates such as the koala (which has two opposable thumbs on each "hand" and fingerprints remarkably similar to human fingerprints) are often described as having either "hands" or "paws" on their front limbs.

Hands are the chief organs for physically manipulating the environment, used for both gross motor skills (such as grasping a large object) and fine motor skills (such as picking up a small pebble). The fingertips contain some of the densest areas of nerve endings on the body, are the richest source of tactile feedback, and have the greatest positioning capability of the body; thus the sense of touch is intimately associated with hands. Like other paired organs (eyes, feet, legs), each hand is dominantly controlled by the opposing brain hemisphere, so that handedness, or the preferred hand choice for single-handed activities such as writing with a pen, reflects individual brain functioning.

Some evolutionary anatomists use the term hand to refer to the appendage of digits on the forelimb more generally — for example, in the context of whether the three digits of the bird hand involved the same homologous loss of two digits as in the dinosaur hand.

The hand has 27 bones, 14 of which are the phalanges (proximal, medial, and distal) of the fingers. The metacarpal is the bone that connects the fingers and the wrist. Each human hand has 5 metacarpals.

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