Introduction:  On  the  basis  of  percent  depth  dose  (PDD)  calculation,  the  application  of  dosimetry  in  radiotherapy  has  an  important  role  to  play  in  reducing  the  chance  of  tumor  recurrence. The aim of this study is to introduce a new formula for calculating the centeral axis  percent depth doses of Cobalt-60 beam.   Materials and Methods: In the present study, based on ...

background: the dosimetric performance of eclipse 6.5 three dimensional treatment planning system (3dtps) is evaluated by comparing the calculated and measured dose in two dimensions following the guide lines of american association for physicists in medicine task group 53. materials and methods: the calculations were performed by the 3dtps for symmetric as well as asymmetric fields for standar...

BACKGROUND Ablation lesion depth caused by radiofrequency-based renal denervation (RDN) was limited to <4 mm in previous animal studies, suggesting that radiofrequency-RDN cannot ablate a substantial percentage of renal sympathetic nerves. We aimed to define the true lesion depth achieved with radiofrequency-RDN using a fine sectioning method and to investigate biophysical parameters that could...

Elevated atmospheric carbon dioxide concentrations [CO2] is projected to increase forest production, which could increase ecosystem carbon (C) storage. This study contributes to our broad goal of understanding the causes and consequences of increased fine-root production and mortality under elevated [CO2] by examining potential gross nitrogen (N) cycling rates throughout the soil profile. Our s...

abstract methods of tillage and organic matter affect root growth and distribution and therefore nutrient uptake by plant and its growth. this study was performed consecutive two years. tillage treatments included disk harrowing + two disk harrowings as reduced tillage (15 cm plowing depth) and moldboard plowing + two disk harrowings as conventional tillage system (30 cm plowing depth). also, t...

The objectives of this study were to compare coarse root (diameter > 2 mm) and fine root (diameter < 2 mm) biomass, as well as distribution of soil carbon stocks in 3 types of riparian land uses across 4 sites located in farmland of southern Québec, Canada: (1) hybrid poplar buffers (9th growing season); (2) herbaceous buffers; (3) natural woodlots (varying in tree species and age). For all lan...

Spartina alterniflora is an invasive C4 perennial grass, native to North America, and has spread rapidly along the east coast of China since its introduction in 1979. Since its intentional introduction to the Jiuduansha Island in the Yangtze River estuary, Spartina alterniflora community has become one of the dominant vegetation types. We investigated the soil carbon in the Spartina alterniflor...

Background: The dosimetric performance of Eclipse 6.5 three dimensional treatment planning system (3DTPS) is evaluated by comparing the calculated and measured dose in two dimensions following the guide lines of American Association for Physicists in Medicine Task Group 53. Materials and Methods: The calculations were performed by the 3DTPS for symmetric as well as asymmetric fields for standar...

Background: Soil microorganisms play key roles in nutrient cycling and are distributed throughout the soil profile. Currently, there is little information about the characteristics of the microbial communities along the soil depth because most studies focus on microorganisms inhabiting the soil surface. To better understand the functions and composition of microbial communities and the biogeoch...