Random Ramblings to 31 January 2010

Acetylcholine
A chemical in the body which transmits messages between a neuron and the nearby cells (a neurotransmitter). Its presence will signal muscles to contract. Nerve agents prevent its breakdown, causing muscles (including those in the heart and lungs) to contract uncontrollably. Atropine, the toxin of deadly nightshade and an antidote of nerve agents, prevents cells from detecting acetylcholine, causing muscles to relax uncontrollably at high doses. Its chemical formula is C₇H₁₆NO₂.

The skeletal formula for acetylcholine.

Acid test
A highly rigorous test for a characteristic of an object, especially for the existence of personality traits and metals. It is often very damaging to the object being tested. This figure of speech originated from the practice of testing for the presence of gold (a noble metal) in a metal object by bathing it in acid. The gold, being very chemically stable, will withstand the acid, while other, less noble metals will dissolve.

Cinnabar
A deep red mineral and a common ore of mercury. A wood fire will easily separate the mercury, which will vaporise into the air. It is also ground and used as the pigment for vermillion (also known as China red). Its chemical formula is HgS.

Cinnabar on dolomite.

Gregorian calendar
A calendar having 365-366 days and 12 months January, February, March, etc.. It is the current internationally accepted calendar for ordinary and governmental use. A Gregorian year having 366 days is called a leap year, which occurs every year both divisible by 4 and not divisible by 100, except every year divisible by 400, in which case they are considered leap years. The following mnemonic describes the number of days in each month:

30 days has September, April, June and November. All the rest have 31, except February alone, which has 28 days clear and 29 days each leap year.

Inoculation
The transfer of an organism into the body system of another organism. In medicine, it refers to the introduction of a weak bacteria, fungus or virus to boost immunity against a disease caused by a related but stronger pathogen. The organism introduced is called the inoculant or inoculum. An inoculant differs from a vaccine in that the vaccine contains a weakened or killed pathogen or fragments of its biological structure.

Unearned revenue
Also known as customer deposits or revenue earned in advance, the portion of a business' liabilities where it has received payment (most often in cash) but not yet provided the product. It is a liability because the business needs to settle it by either returning the payment to the customer or provide the product, in both cases sacrificing the economic benefits in the cash or inventory item. Examples of unearned revenue include customer payments for prepaid mobile telephony, insurance and game time. Customers often refer to it as "credit" because of its credit balance in the business' accounts.

Unearned revenue
Debits:	$	Credits:	$
03/10 Sales	23 000	01/07 Opening balance	12 000
07/05 Sales	38 000	25/09 Cash	39 000
		14/04 Cash	17 000
		31/06 Closing balance	7 000

An example Unearned revenue T-account.

Word length
The number of bits that a computer's CPU will handle as one unit. That word can contain data such as integer numbers, addresses for memory locations and instructions. Current consumer operating systems use either the 32-bit or 64-bit word length. A string of 32 bits can express 4 294 967 296 different values, therefore a 32-bit operating system can only address and store data in up to 4GB of RAM memory. Theoretically, a 64-bit operating system can address up to 16 exabytes of memory.