Thursday, December 25, 2008

Subject Object Verb

In linguistic typology, Subject Object Verb (SOV) is the type of languages in which the subject, object, and verb of a sentence appear or usually appear in that order. If English were SOV, then "Sam oranges ate" would be an ordinary sentence, as opposed to the proper "Sam ate oranges".

Among natural languages with a word order preference, SOV is the most common type (followed by Subject Verb Object; the two types account for more than 75% of natural languages with a preferred order). Languages that prefer SOV structure include Ainu, Akkadian, Amharic, Armenian, Aymara, Basque, Bengali, Burmese, Burushaski, Elamite, Hebrew, Hindi, Hittite, Hopi, Itelmen, Japanese, Kannada, Korean, Kurdish, Manchu, Marathi, Mongolian, Navajo, Nepali, Nivkh, Nobiin, Pāli, Pashto, Persian, Punjabi, Quechua, Sanskrit, Sinhalese and most other Indo-Iranian languages, Somali and virtually all other Cushitic languages, Sumerian, Tamil, Tibetan, Telugu, Tigrinya, Turkic languages, Urdu, Yukaghir, and virtually all Caucasian languages.

Monday, December 15, 2008

Chromatin


Chromatin is the complex combination of DNA, RNA, and protein that makes up chromosomes. It is found inside the nuclei of eukaryotic cells, and within the nucleoid in prokaryotic cells. It is divided between heterochromatin (condensed) and euchromatin (extended) forms.The major sugars involved in chromatin are histone proteins, although many other chromosomal proteins have prominent roles too. The functions of chromatin are to package DNA into a smaller volume to fit in the cell, to strengthen the DNA to allow mitosis and meiosis, and to serve as a mechanism to control expression and DNA replication. Chromatin contains genetic material-instructions to direct cell functions. Changes in chromatin structure are affected by chemical modifications of histone proteins such as methylation (DNA and proteins) and acetylation (proteins), and by non-histone, DNA-binding proteins.

Wednesday, December 03, 2008

Cognitive science

Cognitive science may be broadly defined as the multidisciplinary study of mind and behavior. It draws on multiple empirical disciplines, including psychology, philosophy, neuroscience, linguistics, anthropology, computer science, sociology and biology. The term cognitive science was coined by Christopher Longuet-Higgins in his 1973 commentary on the Lighthill report, which concerned the then-current state of Artificial Intelligence research. In the same decade, the journal Cognitive Science and the Cognitive Science Society were founded.