Search results for " beam"

Measurement of the lifetime of tau-lepton

1996

The tau lepton lifetime is measured with the L3 detector at LEP using the complete data taken at centre-of-mass energies around the Z pole resulting in tau_tau = 293.2 +/- 2.0 (stat) +/- 1.5 (syst) fs. The comparison of this result with the muon lifetime supports lepton universality of the weak charged current at the level of six per mille. Assuming lepton universality, the value of the strong coupling constant, alpha_s is found to be alpha_s(m_tau^2) = 0.319 +/- 0.015(exp.) +/- 0.014 (theory). The tau lepton lifetime is measured with the L3 detector at LEP using the complete data taken at centre-of-mass energies around the Z pole resulting in τ τ =293.2 ± 2.0 (stat) ± 1.5 (syst) fs . The c…

Nasal anomalies review with CT or MRI: from congenital to malignant.

2014

Learning Objectives. To describe imaging findings of a wide spectrum of uncommon nasal cavity masses evaluated at our institution by CT, CBCT and MR imaging, clinically and pathologically proven. Background. In this work we present a succinct review of disease illustrated by a retrospective case series of nasalcavity masses, evaluated at our institution. between 2010 and 2013. Patients have been studied with different imaging modalities including multiraw computed tomography (CT), cone beam computed tomography (CBCT) and magnetic resonance imaging (MR) to illustrate the findings and to summarize the main diagnostic keypoints for the differential diagnosis of nasal masses. Clinicopathologica…

External-beam radiotherapy as preparative regimen for hepatocyte transplantation after partial hepatectomy

2006

Purpose: The transplantation of donor hepatocytes is considered a promising option to correct chronic liver failure through repopulation of the diseased organ. This study describes a novel selective external-beam irradiation technique as a preparative regimen for hepatocyte transplantation. Methods and Materials: Livers of dipeptidylpeptidase IV (DPPIV)–deficient rats were preconditioned with external-beam single-dose irradiation (25 Gy) delivered to two thirds of the liver. Four days later, a one-third partial hepatectomy (PH) was performed to resect the untreated liver section, and 15 million wild-type (DPPIV + ) hepatocytes were transplanted via the spleen into the recipient livers. The …

Prostate Metabolism After the Completion of Exclusive Radiation Is More Depleted After Seeds Brachytherapy Compared to External Beam Radiation Therap…

2012

International audience; Biochemical outcome after radiation therapy requires a protracted time. PSA decreases slowly over time so that it is difficult to differentiate immediately after the completion of radiation the impact of radiation in the prostate using brachytherapy or external radiotherapy. At 3 months, the mean PSA values were similar between the 2 groups: 2.54 ng/mL (±1.59) in the EBRT group and 1.88 ng/mL (±1.14) in the PPI group (p=0.23). For Choline levels, 3-months Choline / Baseline Choline ratios were 1.13 (±0.60) after EBRT vs. 0.45 (±0.23) in the PPI group (p=0.003). Similar results were observed for Citrate levels: 3-months Citrate level / Baseline Citrate level ratios we…

Fractionated External Beam Radiotherapy as a Suitable Preparative Regimen for Hepatocyte Transplantation After Partial Hepatectomy

2010

Purpose Hepatocyte transplantation is strongly considered to be a promising option to correct chronic liver failure through repopulation of the diseased organ. We already reported on extensive liver repopulation by hepatocytes transplanted into rats preconditioned with 25-Gy single dose selective external beam irradiation (IR). Herein, we tested lower radiation doses and fractionated protocols, which would be applicable in clinical use. Methods and Material Livers of dipeptidylpeptidase IV (DPPIV)-deficient rats were preconditioned with partial liver external beam single dose IR at 25 Gy, 8 Gy, or 5 Gy, or fractionated IR at 5 × 5 Gy or 5 × 2 Gy. Four days after completion of IR, a partial …

Changing trends in the national practice for external beam radiotherapy for children with central nervous system tumours in Spain: results from the c…

2003

Mapping Carbon Stocks In Central And South America With Smap Vegetation Optical Depth

2019

Mapping carbon stocks in the tropics is essential for climate change mitigation. Passive microwave remote sensing allows estimating carbon from deep canopy layers through the Vegetation Optical Depth (VOD) parameter. Although their spatial resolution is coarser than that of optical vegetation indices or airborne Lidar data, microwaves present a higher penetration capacity at low frequencies (L-band) and avoid cloud masking. This work compares the relationships of airborne carbon maps in Central and South America with both (i) SMAP L-band VOD at 9 km gridding and (ii) MODIS Enhanced Vegetation Index (EVI). Models to estimate carbon stocks are built from these two satellite-derived variables.…

TENACITÀ ALLA FRATTURA INTERLAMINARE DI COMPOSITI CFRP SOTTOPOSTI A PROCESSI DI INVECCHIAMENTO IDROTERMICO

2011

In questo lavoro si è condotto uno studio degli effetti dell’invecchiamento idrotermico sulla tenacità alla frattura interlaminare in Modo I di laminati in composito CFRP con lay-up unidirezionale. I pannelli realizzati impiegano una resina epossidica DGEBA. Provini DCB sono stati ricavati in accordo con la norma ASTM D5528. Prove dinamico meccaniche DMTA sono state condotte per analizzare l’influenza dell’invecchiamento sulla temperatura di transizione vetrosa, e quindi sul grado di fragilità della matrice. Il lavoro descrive il set-up sperimentale per la determinazione delle Curve R, evidenziando l’influenza della morfologia del tessuto in carbonio. I valori di GIC di innesco e di propaga…

SU-E-J-64: Evaluation of a Commercial EPID-Based in Vivo Dosimetric System in the Presence of Lung Tissue Heterogeneity

2014

Purpose: To study the performance of Dosimetry Check (DC), an EPID-based dosimetry software, which allows performing transit dosimetry, in low density medium, by comparing calculations in-phantom, and analysing results for 15 lung patients. Methods: DC software (v.3.8, pencil beam-based algorithm) has been tested, for plans (Eclipse v.10.0 TPS) delivered in two Varian Clinac iX equipped with aS1000 EPIDs.In the CIRS lung phantom, comparisons between DC and Eclipse (Acuros) were performed for several plans: (1) four field box; (2) square field delivered in arc mode; (3) RapidArc lung patient plan medially centred; (4) RapidArc lung patient plan centred in one lung. Reference points analysed:…

Craniomaxillofacial morphology alterations in children, adolescents and adults with neurofibromatosis 1 : a cone beam computed tomography analysis of…

2017

Background Oral manifestations are common in neurofibromatosis 1 (NF1), and include jaws and teeth alterations. Our aim was to investigate the craniomaxillofacial morphology of Brazilian children, adolescents and adults with NF1 using cone beam computed tomography. Material and Methods This study was conducted with 36 Brazilian individuals with NF1 with ages ranging from 4 to 75. The participants were submitted to anamnesis, extra and intraoral exam and cephalometric analysis using cone beam computed tomography. Height of the NF1 individuals was compared to the length of jaws and skull base. The results of the cephalometric measurements of the NF1 group were compared with a control group pa…