[1] Controls on interannual variations in water and energy balances of large river basins (10,000 km and greater) are evaluated in the framework of the semiempirical relation E=P 1⁄4 1⁄21þ ðR=PÞ n 1/n in which and E, P, and R are basin mean values of annual evaporation, precipitation, and surface net radiation, respectively, expressed as equivalent evaporative water flux, overbars denote long-t...

Organs at risk are defined as normal tissues whose radiation sensitivity may significantly influence treatment planning and/or prescribed radiation dose. These organs at risk may be particularly vulnerable to clinically important complications from radiation toxicity. The following table outlines radiation doses that are generally considered tolerance thresholds for these normal structures in t...

background: ultraviolet (uv) radiation is divided into three regions: uva, uvb, and uvc. both the quality and quantity of solar uv radiation vary with various factors including the elevation of the sun above the horizon, as well as absorption and scattering of uv photons by molecules in the atmosphere, notably ozone and clouds. it is clear that whereas a moderate amount of uv exposure is benefi...

Helical tomotherapy is a dedicated intensity modulated radiation therapy (IMRT) system with on-board imaging capability (MVCT) and therefore differs from conventional treatment units. Different design goals resulted in some distinctive radiation field characteristics. The most significant differences in the design are the lack of flattening filter, increased shielding of the collimators, treatm...

PURPOSE The fibrates are ligands for peroxisome proliferator-activated receptor (PPAR) α and used clinically as hypolipidemic drugs. The fibrates are known to cause peroxisome proliferation, enhance superoxide dismutase (SOD) expression and catalase activity. The antioxidant actions of the fibrates may modify radiation sensitivity. Here, we investigated the change of the radiation sensitivity i...

Introduction The purpose of the current study was to determine optical sensitivity of N-isopropyl acrylamide NIPAM and polyacrylamide gelatin and tetrakis hydroxymethyl phosphoniun chloride (PAGAT) polymer gels for different wavelength of visible light spectrum applied in optical computed tomography method. Materials and Methods NIPAM and PAGAT polymer gels with conventional formulations used f...

Objective. To evaluate the effectiveness of three-month fluoride varnish application on radiation caries and dental sensitivity and to assess compliance to three-month fluoride varnish application. Materials and Methods. 190 irradiated head and neck cancer patients were randomly selected and reviewed retrospectively. Oral prophylaxis, fluoride varnish application, and treatment of dental caries...