Search results for "RADIO"
showing 10 items of 8895 documents
Positron production using a 9 MeV electron linac for the GBAR experiment
2020
For the GBAR (Gravitational Behaviour of Antihydrogen at Rest) experiment at CERN's Antiproton Decelerator (AD) facility we have constructed a source of slow positrons, which uses a low-energy electron linear accelerator (linac). The driver linac produces electrons of 9 MeV kinetic energy that create positrons from bremsstrahlung-induced pair production. Staying below 10 MeV ensures no persistent radioactive activation in the target zone and that the radiation level outside the biological shield is safe for public access. An annealed tungsten-mesh assembly placed directly behind the target acts as a positron moderator. The system produces $5\times10^7$ slow positrons per second, a performan…
Ultrasound bioeffects in rats: quantification of cellular damage in the fetal liver after pulsed Doppler imaging
2011
Objective To determine whether pulsed Doppler examination of the ductus venosus in rat fetuses could damage exposed tissue. Methods On gestational day 18, the livers of a mean of approximately five fetuses per mother (n = 5.14, SD = 1.6), in a cohort of 35 pregnant female rats, were exposed individually to pulsed Doppler and these were considered the 'exposed group'. The remaining fetuses in each pregnant rat (n = 5.16, SD = 2.1) formed the 'control group'. We tested for 600, 300, 60, 20, 15, 10 and 3 s of exposure of the fetal ductus venosus and the damage was evaluated measuring a cell death index of apoptotic activity at 7 h post-exposure (n = 16). In addition, subgroups of mothers were …
Intravenous Contrast Material for Cardiac Computed Tomography
2023
Purpose: The Italian Registry of Contrast Material use in Cardiac Computed Tomography (iRCM-CCT) is a multicenter, multivendor, observational study on the use of contrast media (CM) in patients undergoing cardiac computed tomography (CCT). The aim of iRCM-CCT is to assess image quality and safety profile of intravenous CM compounds. Materials and methods: iRCM-CCT enrolled 1842 consecutive patients undergoing CCT (≥50 per site) at 20 cluster sites with the indication of suspected coronary artery disease. Demographic characteristics, CCT, and CM protocols, clinical indications, safety markers, radiation dose reports, qualitative (ie, poor vascular enhancement) and quantitative (ie, HU attenu…
An International Survey of Quality and Safety Programs in Radiology
2021
Purpose: The aim of this study was to determine the status of radiology quality improvement programs in a variety of selected nations worldwide. Methods: A survey was developed by select members of the International Economics Committee of the American College of Radiology on quality programs and was distributed to committee members. Members responded on behalf of their country. The 51-question survey asked about 12 different quality initiatives which were grouped into 4 themes: departments, users, equipment, and outcomes. Respondents reported whether a designated type of quality initiative was used in their country and answered subsequent questions further characterizing it. Results: The re…
Double blind randomized clinical trial comparing minimally- invasive envelope flap and conventional envelope flap on impacted lower third molar surge…
2022
The latest trend in surgery is to look for minimally invasive procedures, with fewer complications and a shorter recovery time. This study aims to compare the minimally- invasive envelope flap, with smaller incision and fewer dissection and the conventional envelope flap, with a 20mm incision, on impacted mandibular third molar surgery, focusing on the hypothesis that there were no differences in postoperative outcomes. A double-blind randomized clinical trial was designed to compare both incisions, focused on determining the approach with minor postoperative side-effects and minor impact on quality-of-life. A total of 60 patients were enrolled for the study if their presented impacted mand…
Modulation of salivary inflammatory markers and proteomic analysis in HNC and OSCC patients undergoing radiotherapy
2021
Head and neck cancer (HNC) includes malignant tumours that most commonly arise from the oral mucosa or lining of the head and neck regions. They are characterized according to their primary site of origin as malignancies of the nasal cavity and paranasal sinuses, pharynx, larynx, salivary glands and oral cavity. The majority of these neoplasms are epithelial tumours, among them the 90% are squamous cell carcinomas (SCC). HNC including the Oral Squamous cell carcinoma (OSCC), is the sixth most common neoplasia worldwide with an incidence estimated at 650,000 cases and 330,000 deaths per year. Despite all of the diagnostic and therapeutic advances, the 5-year survival rate remains relatively …
Can cystic lesions of the jaws be considered as the cause of mandibular asymmetry?
2021
The aim of this study is to investigate the presence of condylar and ramal asymmetry in patients with a cyst larger than 10 mm in the maxilla or mandible. Condylar and ramal asymmetry index measurements of 47 patients (mean age: 28.85 ± 15.348) in the study group and 40 patients in the control group (mean age: 33.73 ± 13.095) were performed using panoramic radiographs. The study group consists of patients with cysts larger than 10 mm in diameter in the maxilla or mandible. The control group consisted of patients with no radiolucent lesions and no history of trauma. The possible statistical difference between the groups was evaluated by the Mann-Whitney U test. No statistically significant d…
Efectos de un programa de fuerza de alta intensidad de 6 meses de duración sobre parámetros funcionales, clínicos y biomarcadores de imagen en mujere…
2022
Introducción: La sarcopenia se caracteriza por la pérdida de masa, fuerza y funcionalidad de la musculatura en los adultos mayores. La realización de ejercicio físico, y en concreto, el entrenamiento de fuerza, se recomienda para la prevención y manejo de la sarcopenia, pero se desconoce si comporta un beneficio a nivel de calidad y cantidad de la masa muscular según parámetros de imagen por resonancia magnética (IRM). Actualmente, el diagnóstico de sarcopenia está limitado por la falta de consenso en su definición y la heterogeneidad de herramientas que se usan en su análisis. Los criterios diagnósticos deberían incluir, además de una evaluación clínica, unos marcadores objetivos con el fi…
Role of Menopausal Transition and Physical Activity in Loss of Lean and Muscle Mass : A Follow-Up Study in Middle-Aged Finnish Women
2020
In midlife, women experience hormonal changes due to menopausal transition. A decrease especially in estradiol has been hypothesized to cause loss of muscle mass. This study investigated the effect of menopausal transition on changes in lean and muscle mass, from the total body to the muscle fiber level, among 47–55-year-old women. Data were used from the Estrogenic Regulation of Muscle Apoptosis (ERMA) study, where 234 women were followed from perimenopause to early postmenopause. Hormone levels (estradiol and follicle stimulating hormone), total and regional body composition (dual-energy X-ray absorptiometry (DXA) and computed tomography (CT) scans), physical activity level (self-reported…
Manejo de schwannoma vestibular con radiaciones : experiencia del IVO
2013
A partir de la década de los 70, nace la radiocirugía (RC) como tratamiento alternativo a la cirugía convencional en el tratamiento de los schwannomas vestibulares(SV). Poco a poco dicha técnica, ha ido desbancando a la microcirugía alcanzando cifras del 58 % de tratamientos de RC frente a la cirugía convencional. En el presente estudio analizamos el resultado de 167 tumores tratados con radiaciones (bien con dosis única (RC) o con dosis fraccionada, RT Estereotáctica Fraccionada (RTEF), determinando el control local y las complicaciones como tratamiento del SV. Analizamos los resultados en función de la tecnología utilizada para tratarlos, bien colimadores cilíndricos o bien micromutilámin…