Key generation for data cryptography is vital in wireless communications security. This key must be generated in a random way so that can not be regenerated by a third party other than the intended receiver. The random nature of the wireless channel is utilized to generate the encryption key. However, the randomness of wireless channels deteriorated over time due to channel aging which casing security threats, particularly for spatially correlated channels. In this paper, the effect of channel aging on the ciphering key generations is addressed. A proposed method to randomize the encryption key each coherence time is developed which decreases the correlation between keys generated at consecutive coherence times. When compared to the

Enamel White Spot Lesions (EWSLs) are a common dental condition characterized by being opaque or chalky white in appearance. In this review, an overview of the etiology, prevention, and treatment techniques for EWSLs is presented. Enamel demineralization caused by bacteria in dental plaque which releases acids upon the consumption of fermentable carbohydrates causing mineral loss is thought to be the main cause of those lesions, which could be predisposed through orthodontic treatment, poor diet, inadequate oral hygiene and certain medical conditions. So, sustaining an adequate carbohydrate consumption, proper fluoride exposure and good oral hygiene are some of the practices which aid in these lesions’ prevention. Although the suc

  The phenomenon of child labor, any activity performed by a child and represents a contribution to the production, this phenomenon had been rife in Iraqi society, after that the proportion of child labor for the age group (6-14 years) amounting to 3% in 2006, became for  the same age group of 8% in 2008*.                                                      

It is recognized that each phenomenon reasons, the phenomenon which our atten

Doxycycline and levofloxacin are heterocyclic organic compounds that are now popularly used to treat some bacterial infections. In this study which was conducted on patients from a private clinic, we compared the use of two commonly used antibiotics for the treatment of diagnosed cases with vaginal chlamydial infection: levofloxacin and doxycycline. Vaginal chlamydial infection is considered to be a very common sexually transmitted infection. It may have minimal symptoms which can lead to neglect by the patient until it leads to some important complications among which is the inability to become pregnant. This indicates early diagnosis and treatment of this infection. By comparing the results of treatment we concluded that there is no much

BACKGROUND: In 1972 complete description of the
inflammation of posterior third of the vocal cords was
done, with barium swallow confirming Gastro
Esophageal Disease [CRED] & subsequent successful
symptomatic treatment with antacid. The possible
association between GERD & chronic laryngitis was
initially known as acid laryngitis .2
*from the Department of ENT, Hawlear Medical College, Hawlear university. Department of ENT, Rezgary Teaching Hospital, Erbil.
Correspondence to :
Dr.Said Mustafa Said
Corespondence Address to : Dr.Said Mustafa Said _ E- mail: Email [email protected] Mob. 07504563829
Recived at : 15 th Dec 2009 Accepted at : 3ed Nov 2010

OBJECTIVE: To record the common presentat

This study is descriptive and theory of Dawn syndrome as the problem of research lies in the need to identify the identification of the causes of Dawn syndrome and its symptoms and methods of dealing with it, which has become a problem that needs treatment, especially after the numbers have become high in Iraq, which has not yet taken the necessary importance for treatment and care.

The objectives of the research were summarized in the identification of the most important causes of Dawn syndrome and its symptoms and diagnosis and ways or methods of dealing with people with Dawn syndrome in order to develop therapeutic plans for him.