Randomized backo‚ protocols have long been used to reduce contention on shared resources. Œey are heavily used in communication channels and radio networks, and have also been shown to greatly improve the performance of shared memory algorithms in real systems. However, while backo‚ protocols are well understood in many seŠings, their e‚ect in shared memory has never been theoretically analyzed...

Sabkhas are key landforms along the southern coast of Arabian Gulf and represent modern analogues for depositional diagenetic processes controlling properties quality ancient hydrocarbon-bearing carbonates. While previous investigations coastal sabkhas in Qatar have mainly focused on dolomitization processes, presented here is one first studies reconstructing facies changes formation great deta...

1.The study area spend Tikrit in Salah Aden province, and followed him from the aspects villages tubing such as Al-Alam district , Hawi Albu-Ajeel, Al-Naama areas, a series Hamrin mountains east of Tigris River, stretching north to south Al Awja district, Aouinat, Mahzm, Al-Hamra al-Jazeera Lake Tharthar west River.
 
 were collected 1298 fecal sample sheep goats, which 734 samples 56...

Migraine is an important socioeconomic burden and is ranked the sixth cause of years of life lost because of disability in the general population and the third cause of years of life lost in people younger than 50 years. The cornerstone of pharmacological treatment is represented by the acute therapy. The serotonin (5-hydroxytryptamine [5-HT]) receptor subtype 1B/1D agonists, called triptans, a...

Two separate and distinct diamictite-rich units occur in the mixed carbonate-siliciclastic PolarisbreenGroup, which comprises the top kilometer of47 km of Neoproterozoic strata in the northeast of the Svalbard archipelago.The platformal succession accumulated on the windward, tropical to subtropical margin of Laurentia.The older PetrovbreenMember is a thin glacimarine diamictite that lacks a ca...

Remote sensing data can provide valuable information about the surface expression of regional geomorphologic and geological features of arid regions. In the present study, several processing techniques were applied to reveal such in the Qatar Peninsula. Those included preprocessing for radiometric and geometric correction, various enhancement methods, classification, accuracy assessment, contra...

cheshmeh-konan area is located ~15 km northwest of tasuj, east-azarbaidjan province. the most important lithologic units of the area are red sandstones, green-gray sandstones, shale, and marl (miocene). based on field evidence and petrographical investigations, the host sediments were deposited in a peritidal setting associated with a sabkha-type environment. copper mineralization in the area o...