The Hellenic Navy (HN) (Greek: Πολεμικό Ναυτικό, Polemikó Naftikó, abbreviated ΠΝ) is the naval force of Greece, part of the Greek Armed Forces. The modern Greek navy has its roots in the naval forces of various Aegean Islands, which fought in the Greek War of Independence. During the periods of monarchy (1833–1924 and 1936–1973) it was known as the Royal Navy (Βασιλικόν Ναυτικόν, Vasilikón Naftikón, abbreviated ΒΝ).The total displacement of all the navy's vessels is approximately 150,000 tons.The motto of the Hellenic Navy is "Μέγα το της Θαλάσσης Κράτος" from Thucydides' account of Pericles' oration on the eve of the Peloponnesian War. This has been roughly translated as "Great is the country that controls the sea". The Hellenic Navy's emblem consists of an anchor in front of a crossed Christian cross and trident, with the cross symbolizing Greek Orthodoxy, and the trident symbolizing Poseidon, the god of the sea in Greek mythology. Pericles' words are written across the top of the emblem. "The navy, as it represents a necessary weapon for Greece, should only be created for war and aim to victory."...............The Hellenic Merchant Marine refers to the Merchant Marine of Greece, engaged in commerce and transportation of goods and services universally. It consists of the merchant vessels owned by Greek civilians, flying either the Greek flag or a flag of convenience. Greece is a maritime nation by tradition, as shipping is arguably the oldest form of occupation of the Greeks and a key element of Greek economic activity since the ancient times. Nowadays, Greece has the largest merchant fleet in the world, which is the second largest contributor to the national economy after tourism and forms the backbone of world shipping. The Greek fleet flies a variety of flags, however some Greek shipowners gradually return to Greece following the changes to the legislative framework governing their operations and the improvement of infrastructure.Blogger Tips and Tricks
This is a bilingual blog in English and / or Greek and you can translate any post to any language by pressing on the appropriate flag....Note that there is provided below a scrolling text with the 30 recent posts...Αυτό είναι ένα δίγλωσσο blog στα Αγγλικά η/και στα Ελληνικά και μπορείτε να μεταφράσετε οποιοδήποτε ποστ σε οποιαδήποτε γλώσσα κάνοντας κλικ στη σχετική σημαία. Σημειωτέον ότι παρακάτω παρέχεται και ένα κινούμενο κείμενο με τα 30 πρόσφατα ποστς....This is a bilingual blog in English and / or Greek and you can translate any post to any language by pressing on the appropriate flag....Note that there is provided below a scrolling text with the 30 recent posts...Αυτό είναι ένα δίγλωσσο blog στα Αγγλικά η/και στα Ελληνικά και μπορείτε να μεταφράσετε οποιοδήποτε ποστ σε οποιαδήποτε γλώσσα κάνοντας κλικ στη σχετική σημαία. Σημειωτέον ότι παρακάτω παρέχεται και ένα κινούμενο κείμενο με τα 30 πρόσφατα ποστς.........

Sunday, July 11, 2010

Controlling termite reproduction..[ 1427 ]

'Queen pheromone' controlling termite reproduction found, pest control uses expected


A group of giant queen termites, left, a black, striped king termite and smaller worker termites. Eggs can be seen in the top right corner. (Photo courtesy of Kenji Matsuura)
 A group of giant queen termitesl left a black striped king termite and smaller worker-termites. 
Eggs can be seen in top roght corner. (Photo courtesy of Kenji Matsuura )

(Mainichi Japan) July 11, 2010
Researchers have identified the fruit-scented components of the "queen pheromone" that queen termites give off to control the reproductive capacity of each colony.
Queen termites are apparently preventing other females from becoming new queens by giving off a fruit-like odor. Researchers expect that by artificially creating the same pheromone, termites can be controlled effectively.

A termite colony consists of king, queen and worker termites, with only queens producing eggs. When queens die or become sterile, several other females in the same colony become new queens to take over reproduction. However, as long as there are a sufficient number of eggs in the colony, queens will not increase.

What kind of chemicals were contributing to maintaining this biological mechanism had been a mystery for 50 years.

A research team led by Okayama University associate professor Kenji Matsuura collected 100 queens from each of two termite colonies in Okayama Prefecture and analyzed a small amount of a substance they produced.

As a result, the researchers identified that one secreted substance contained two aromatic components found in fruit -- one contained in fruits like apples and bananas, and the other found in grapes.

When researchers placed each of these chemicals close to the group of worker termites in the absence of a queen, the number of females transforming into new queens increased. However, when the chemicals were mixed together and placed near the colony, the number of new queens stopped increasing. Based on the results, the research team concluded that these two components form the "queen pheromone."

Matsuura says the number of queens in each colony varies depending on the size of nest, and is apparently controlled using the queen pheromone to avoid producing too many eggs for worker termites to look after.

The artificial queen pheromone will effectively prevent female termites from transforming into new queens and laying eggs to reform a colony, researchers said.
The findings were published in the online version of the journal Proceedings of the National Academy of Sciences of the United States of America on July 6.
Click here for the original Japanese story

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