Tuesday, July 31, 2007

Headphones

Headphones are a pair of small loudspeakers, or less commonly a single speaker, with a way of holding them close to a user's ears and a means of linking them to a stereophonic or monophonic audio-frequency signal source such as an audio amplifier, radio, etc. In the context of telecommunication, the term headset is used to describe a combination of Headphone and microphone used for two-way communication, for example with a telephone.

Sunday, July 22, 2007

Time server

A time server is a server computer that reads the actual time from a orientation clock and distributes this information to its clients using a computer network. The time server may be a local network time server or an internet time server. The majority important and widely-used protocol for distributing and synchronizing time is the Network Time Protocol, though other less-popular or outdated time protocols continue in use. The time reference used by a time server could be another time server on the network or the Internet, a connected radio clock or an atomic clock. The most common true time source is a GPS or GPS master clock. Time servers are sometimes multi-purpose network servers, dedicated network servers, or dedicated devices. All a dedicated time server does is provide accurate time.

Friday, July 13, 2007

Cookie

In the United States and Canada, a cookie is a tiny, round, flat cake. In most English-speaking countries outer North America, the most common word for this is biscuit; in many regions both terms are used, while in others the two words have diverse meanings—a cookie is a bun in Scotland, while in the United States a biscuit is a kind of quick bread not unlike a scone.

Cookies can be baked until crisp or just long enough that they stay soft. Depending on the kind of cookie, some cookies are not cooked at all. Cookies are made in a broad variety of styles, using an array of ingredients including sugars, spices, chocolate, butter, peanut butter, nuts or dried fruits. The smoothness of the cookie may depend on how long it is baked.

Prevention

In medicine, prevention is any action which reduces the burden of mortality or morbidity from disease. This takes place at primary, secondary and tertiary prevention levels.Primary prevention avoids the development of a disease. Most population-based health support activities are primary preventive measures.Secondary prevention activities are aimed at early disease detection, thereby increasing opportunities for interventions to prevent progression of the disease and emergence of symptoms.Tertiary prevention reduces the negative impact of an already recognized disease by restoring function and reducing disease-related complications.

Sunday, July 08, 2007

Blue rose

Since roses lack a gene to create delphinidin, the primary plant pigment that produces true blue flowers, blue roses were usually created by dyeing white roses. So-called "blue roses" have been breed by conventional hybridization methods, but the results, such as "Blue Moon" are more precisely described as lilac in color. However, after 13 years of joint research by an Australian company Florigene, and Japanese company Suntory, a blue rose was formed in 2004 by genetic engineering. The delphinidin gene was cloned from the petunia and inserted into a mauve-blend rose, the Old Garden Rose 'Cardinal de Richelieu.' (a Rosa gallica) However, since the pigment cyanidin was still present, the rose was more dark burgundy than true blue. Further work on the rose using RNAi technology to depress the production of cyanidin produced a very dark mauve plant, with only trace amounts of cyanidin.

Sunday, July 01, 2007

Topiary

Topiary is the art of creating sculptures using clipped trees, shrubs and sub-shrubs. The word derives from the Latin word for an ornamental landscape gardener, topiarius, creator of topia or "places", a Greek word that Romans applied also to fictive indoor landscapes executed in fresco. No doubt the use of a Greek word betokens the art's origins in the Hellenistic world that was influenced by Persia, for neither Classical Greece nor Republican Rome developed any complicated tradition of artful pleasure grounds.
The plants used in topiary are evergreen, have small leaves or needles, produce dense foliage, and have compact and/or columnar growth habits. Common plants used in topiary comprise cultivars of box, arborvitae, bay laurel, holly, myrtle, yew, and privet. Shaped wire cages are sometimes working in modern topiary to guide untutored shears, but traditional topiary depends on patience and a steady hand; small-leaved ivy can be used to cover a cage and provide the look of topiary in a few months.