Quality indexes based on water measurements for low and medium energy x-ray beams: a theoretical study with PENELOPE.

Med Phys

Departamento de Física Atómica, Molecular y Nuclear, Universidad de Granada, E-18071 Granada, Spain.

Published: January 2014

Purpose: To study the use of quality indexes based on ratios of absorbed doses in water at two different depths to characterize x-ray beams of low and medium energies.

Methods: A total of 55 x-ray beam spectra were generated with the codes XCOMP5R and SPEKCALC and used as input of a series of Monte Carlo simulations performed with PENELOPE, in which the percentage depth doses in water and the kQ,Q0 factors, defined in the TRS-398 protocol, were determined for each beam. Some of these calculations were performed by simulating the ionization chamber PTW 30010.

Results: The authors found that the relation between kQ,Q0 and the ratios of absorbed doses at two depths is almost linear. A set of ratios statistically compatible with that showing the best fit has been determined.

Conclusions: The results of this study point out which of these ratios of absorbed doses in water could be used to better characterize x-ray beams of low and medium energies.

Download full-text PDF

Source
http://dx.doi.org/10.1118/1.4836556DOI Listing

Publication Analysis

Top Keywords

low medium
12
x-ray beams
12
ratios absorbed
12
absorbed doses
12
doses water
12
quality indexes
8
indexes based
8
characterize x-ray
8
beams low
8
water
4

Similar Publications

Background: Although psychological interventions can be effective for the treatment of major depressive disorder, some patients' symptoms persist or rapidly recur after therapy. This study aimed to synthesize research findings on predictors and moderators of treatment response for persisting forms of depression, such as chronic, recurrent, and treatment-resistant depression.

Methods: A systematic review of studies investigating predictors and moderators of response to outpatient psychological treatment for adults with persisting forms of depression was conducted by searching Web of Science, Scopus, and PsycInfo.

View Article and Find Full Text PDF

Introduction: Social isolation is a main risk factor for loneliness, health issues and psychological diseases. With its restriction measures, the coronavirus pandemic has led to an objective reduction in meaningful interactions, communication, and social contacts in general (social isolation). However, it has been shown that older adults cope differently with social isolation.

View Article and Find Full Text PDF

Primary human mast cells (MC) obtained through culturing of blood-derived MC progenitors are the preferred model for the study of MRGPRX2- IgE-mediated MC activation. In order to assess the impact of culture conditions on functional MRGPRX2 expression, we cultured CD34-enriched PBMC from peripheral whole blood (PB) and buffy coat (BC) samples in MethoCult medium containing stem cell factor (SCF) and interleukin (IL)-3, modified through variations in seeding density and adding or withholding IL-6, IL-9 and fetal bovine serum (FBS). Functional expression of MRGPRX2 was assessed after 4 weeks via flow cytometry.

View Article and Find Full Text PDF

Background: To compare the impact of two different lipid emulsions, specifically a soybean oil-based emulsion and a multiple oil emulsion (soybean oil, medium-chain triglycerides, olive oil, and fish oil, SMOF), on serum metabolites of very low birth weight (VLBW) infants using untargeted metabolomics analysis.

Methods: A comparative study was conducted on 25 VLBW infants hospitalized in neonatal intensive care units (NICU) of Hangzhou Women's Hospital in 2023. The infants were divided into the SMOF group (13 cases) and the soybean oil group (12 cases) based on the type of lipid emulsion used during parenteral nutrition.

View Article and Find Full Text PDF

Background: Stress is closely related to depression, anxiety, and sleep problems. However, few studies have explored the complex symptom-level relationships among these variables at different stress levels among college students.

Methods: From March to April 2024, a survey was conducted using a convenience sampling method in three universities in Daqing City, Heilongjiang Province.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!