Search results for "emission"
showing 10 items of 2441 documents
Alterations in 18F-FDG accumulation into neck-related muscles after neck dissection for patients with oral cancers
2015
Background: 18 F-fluoro-2-deoxy-D-glucose ( 18 F-FDG) accumulations are commonly seen in the neck-related muscles of the surgical and non-surgical sides after surgery with neck dissection (ND) for oral cancers, which leads to radiologists having difficulty in diagnosing the lesions. To examine the alterations in 18 F-FDG accumulation in neck-related muscles of patients after ND for oral cancer. Material and Methods: 18 F-FDG accumulations on positron emission tomography (PET)-computed tomography (CT) in neck-related muscles were retrospectively analyzed after surgical dissection of cervical lymph nodes in oral cancers. Results: According to the extent of ND of cervical lymph nodes, the rate…
68 ga-dotatoc pet/ct follow up after single or hypofractionated gamma knife icon radiosurgery for meningioma patients
2021
68Ga-DOTATOC represents a useful tool in tumor contouring for radiosurgery planning. We present a case series of patients affected by meningiomas on who we performed 68Ga-DOTATOC positron emission tomography (PET)/CT pre-operatively, a subgroup of which also underwent a post-operative 68Ga-DOTATOC PET/CT to evaluate the standardized uptake value (SUV) modification after Gamma Knife ICON treatment in single or hypofractionated fractions. Twenty patients were enrolled/included in this study: ten females and ten males. The median age was 52 years (range 33–80). The median tumor diameter was 3.68 cm (range 0.12–22.26 cm), and the median pre-radiotherapy maximum SUV value was 11 (range 2.3–92). …
Giustizia, morale e mercato delle emissioni
2009
L'autore, Simon Caney, si interroga sulle questioni di giustizia poste dall’attribuzione di responsabilità e oneri per la tutela ambientale. L’attenzione viene focalizzata sulle implicazioni connesse all’istituzione di mercati dell’anidride carbonica, nel quadro delle misure previste dal Protocollo di Kyoto. In primo luogo vengono dissipati i dubbi sulla pretesa scorrettezza o ingiustizia di un simile strumento, osservando che regolare l’emissione di anidride carbonica, in particolare mediante l’assegnazione di diritti e doveri in capo ai singoli attori, è necessario qualora si voglia preservare l’atmosfera. Si tratta piuttosto di stabilire quali soluzioni siano le più conformi a giustizia,…
Measurements of gaseous elemental mercury (GEM) in diffuse soil emission using the static closed-chamber method
2015
Measurements aimed to evaluate the contribution of natural and anthropogenic gaseous elemental mercury (GEM) to the atmosphere are critical for monitoring and mitigating the impact of this highly toxic air contaminant. Notwithstanding, the amounts of GEM originating from different sources are difficult to be estimated, since specific protocols dictating the most appropriate sampling and analytical techniques are lacking. This study was aimed to test a methodological approach enables to measure GEM released through diffuse degassing from the soil, a mechanism that in volcanic and geothermal areas significantly contributes to the discharge of geogenic fluids to the atmosphere. A static closed…
Mercury from volcanoes: fluxes and speciation
2008
Mercury is a toxic bio-accumulating metal that, due to its volatility has an extended atmospheric lifetime. Understanding Hg sources and sinks is therefore has importance on the global scale. We present new measurements of volcanic Hg from Mount Etna and Vulcano in Italy and Masaya volcano in Nicaragua to improve our estimates of the volcanic Hg flux. In contrast to other metals emitted from volcanoes, volcanic Hg can exist in 3 forms, namely gaseous elemental mercury (GEM), reactive gaseous mercury (RGM) and in the particle phase. These measurements also represent the first fully speciated measurements of volcanic Hg, as well as the first high time resolution measurements of gaseous Hg. Vo…
Analytical model for the long- distance tracer-transport in plants
2011
International audience; Recent investigations of long-distance transport in plants using non-invasive tracer techniques such as C radiolabeling monitored by positron emission tomography (PET) combined with magnetic resonance imaging (MRI) revealed the need of dedicated methods to allow a quantitative data analysis and comparison of such experiments. A mechanistic compartmental tracer transport model is presented, defined by a linear system of partial differential equations (PDEs). This model simplifies the complexity of axial transport and lateral exchanges in the transport pathways of plants (e.g. the phloem) by simulating transport and reversible exchange within three compartments using j…
Model, software and database for line-mixing effects in the ν3 and ν4 bands of CH4 and tests using laboratory and planetary measurements-I: N2(and ai…
2006
International audience; Absorption spectra of the infrared ν3 and ν4 bands of CH4 perturbed by N2 over large ranges of pressure and temperature have been measured in the laboratory. A theoretical approach accounting for line mixing is proposed to (successfully) model these experiments. It is similar to that of Pieroni et al. [J Chem Phys 1999;110:7717–32] and is based on state-to-state rotational cross-sections calculated with a semi-classical approach and a few empirical parameters. The latter, which enable switching from the state space to the line space, are deduced from a fit of a single room temperature spectrum of the ν3 band at 50 atm. The comparisons between numerous measured and ca…
The Italian Society of Gastroenterology (SIGE) and the Italian Group for the study of Inflammatory Bowel Disease (IG-IBD) Clinical Practice Guideline…
2010
Biological therapies are an important step in the management of Inflammatory Bowel Diseases. In consideration of high cost and safety issues there is the need to have clear recommendations for their use. Despite the American Gastroenterological Association and the European Crohn's and Colitis Organisation have published exhaustive Inflammatory Bowel Disease guidelines, national guidelines may be necessary as cultural values, economical and legal issues may differ between countries. For these reasons the Italian Society of Gastroenterology and the Italian Group for the study of Inflammatory Bowel Disease have decided to elaborate the Italian guidelines on the use of biologics in Inflammatory…
Determination of metal concentrations in certified plastic reference materials after small-size autoclave and microwave-assisted digestion followed w…
2017
Abstract The digestion methods for the determination of As, Cd, Cr, Pb, Sb, Sn and Zn concentrations in plastic samples using microwave-assisted digestion (MW-AD) and small-size autoclave digestion was developed. The certified polyethylene, polypropylene, polyvinyl chloride and acrylonitrile butadiene styrene certified reference materials were used in order to find digestion method working properly for several sample matrices. Efficiency of the digestion methods was evaluated by analyzing the residual carbon in digests by TOC analyzer. MW-AD using a mixture of 7 mL of HNO 3 and 3 mL of H 2 O 2 as a digestion solution resulted in excellent recoveries for As, Cd, Pb, Sb and Zn, and were in th…
The determination of trace element concentrations in fly ash samples using ultrasound-assisted digestion followed with inductively coupled plasma opt…
2009
A method of ultrasound-assisted digestion followed by inductively coupled plasma optical emission spectrometry (ICP-OES) used for the determination of trace element (chromium, copper, lead, nickel, vanadium and zinc) concentrations in fly ash samples was developed. All the measurements were performed in robust plasma conditions. Ultrasound-assisted digestion procedures using digestion solutions of aqua regia and hydrofluoric acid (HF) resulted in recovery rates of over 80% for all the analyte elements. Ultrasound-assisted two-step digestion with digestion solutions of 6 mL of HNO₃(Step 1) and 3 mL of HNO₃+ 3 mL of HF (Step 2) resulted in recovery rates of over 92% for all the analyte elemen…