Search results for "emissio"
showing 10 items of 2450 documents
Comparison of 99mTc-Labeled Colloid SPECT/CT and Planar Lymphoscintigraphy in Sentinel Lymph Node Detection in Patients with Melanoma: A Meta-Analysis
2020
We compared the detection rate (DR) for sentinel lymph nodes (SLNS), the number of SLNs and the subjects with additional SLNs of single-photon emission computed tomography (SPECT/CT) and planar lymphoscintigraphy (PL) in patients with melanoma. Furthermore, we evaluated the impact of SPECT/CT on surgical plans. Articles containing head-to-head comparisons between SPECT/CT and PL were searched in Pubmed/MEDLINE and Scopus. The literature search was updated until December 31st, 2019. DR was calculated on a per-patient-based analysis; the studies were pooled by their odds ratios (ORs) with a random effects model to assess the significance of difference (p < 0.05). The number of additional S…
Dynamic regimes of cyclotron instability in the afterglow mode of minimum-B electron cyclotron resonance ion source plasma
2016
The paper is concerned with the dynamic regimes of cyclotron instabilities in non-equilibrium plasma of a minimum-B electron cyclotron resonance ion source operated in pulsed mode. The instability appears in decaying ion source plasma shortly (1–10 ms) after switching off the microwave radiation of the klystron, and manifests itself in the form of powerful pulses of electromagnetic emission associated with precipitation of high-energy electrons along the magnetic field lines. Recently it was shown that this plasma instability causes perturbations of the extracted ion current, which limits the performance of the ion source and generates strong bursts of bremsstrahlung emission. In this artic…
Characteristic Kα emission of electron cyclotron resonance ion source plasmas
2018
This thesis presents the results of an investigation of the volumetric Kα emission rate/inner shell ionization rate from an Electron Cyclotron Resonance Ion Source (ECRIS) plasma tuned predominantly for high charge state ion production. The experimental work include four complimentary studies covering the influence of a parametric sweep of the four source tune parameters i.e microwave power, neutral gas flow, biased disc voltage and magnetic field on the volumetric Kα emission rate, an investigation into the gas mixing effect, an investigation into the effectiveness of double-frequency heating mode and finally an investigation into microwave induced electron losses (relative and direct) from th…
Photoelectron emission experiments with ECR-driven multi-dipolar negative ion plasma source
2017
Photoelectron emission measurements have been performed using a 2.45 GHz ECR-driven multi-dipolar plasma source in a low pressure hydrogen discharge. Photoelectron currents induced by light emitted from ECR zone and H− production region are measured from Al, Cu, Mo, Ta, and stainless steel (SAE 304) surfaces as a function of microwave power and neutral hydrogen pressure. The total photoelectron current from the plasma chamber wall is estimated to reach values up to 1 A for 900 W of injected microwave power. It is concluded that the volumetric photon emission rate in wavelength range relevant for photoelectron emission is a few times higher in arc discharge. peerReviewed
VUV emission spectroscopy combined with H- density measurements in the ion source Prometheus I
2016
“Prometheus I” is a volume H− negative ion source, driven by a network of dipolar electron cyclotron resonance (ECR; 2.45 GHz) modules. The vacuum-ultraviolet (VUV) emission spectrum of low-temperature hydrogen plasmas may be related to molecular and atomic processes involved directly or indirectly in the production of negative ions. In this work, VUV spectroscopy has been performed in the above source, Prometheus I, both in the ECR zones and the bulk (far from ECR zones and surfaces) plasma. The acquired VUV spectra are correlated with the negative ion densities, as measured by means of laser photodetachment, and the possible mechanisms of negative ion production are considered. The well-e…
Political Economy of the Emission Reduction Measures
2015
Celem niniejszego tekstu jest krytyczna analiza środków podejmowanych przez Unię Europejską na rzecz zmniejszenia emisji dwutlenku węgla. Analiza obejmuje również inne, alternatywne metody walki z emisjami, jak również możliwe do zaaplikowania reformy aktualnego system ETS. Przywoływane argumenty dotyczą perspektywy politycznej i ekonomicznej walki z emisjami, jako jednego z elementów polityki klimatycznej i energetycznej podejmowanej w Europie.
Inter-crystal scatter in positron emission tomography: Identification techniques and effects on reconstructed images for AX-PET demonstrator
2012
La PET es una técnica de imagen en medicina nuclear que permite la visualización in-vivo y en 3D de procesos funcionales en seres vivos. Un escáner PET mide los rayos gamma producidos al aniquilarse un positrón, el cual es emitido por un radioisótopo inyectado al paciente. La eficiencia del sistema es una característica crucial de los escáneres PET de alta resolución dedicados a la imagen del cerebro o de animales pequeños con el fin de obtener una imagen más fiel o de reducir la actividad del radiotrazador, y por consiguiente, la dosis inyectada al paciente. El objetivo de este trabajo de investigación es mejorar la eficiencia y calidad de imagen de un prototipo de escáner PET axial (AX-PE…
Akillesjännekipupotilaiden pohjelihasharjoituksen aikainen aivoaktivaatio ja kuntoutusjakson vaikutus aktivaatioon
2011
Flink, Riina 2011. Akillesjännekipupotilaiden pohjelihasharjoituksen aikainen aivoakti-vaatio ja kuntoutusjakson vaikutus aktivaatioon. Liikuntabiologian laitos. Jyväskylän Yliopisto. Biomekaniikan Pro Gradu – tutkielma, 88s. Nivelien, alaselän ja akillesjänteiden kiputilat ovat nykyään hyvin yleisiä. Kuitenkaan kroonisen kivun hoitokeinot eivät ole yhtä kehittyneitä kuin akuutin kivun hoitokeinot. Tähän osasyynä on tietämättömyys kroonisen kivun vaikutuksista elimistöön. Etenkin kroonisen kivun vaikutukses-ta tahdonalaiseen liikkeeseen on hyvin vähän tietoa. Tämän tutkimuksen tarkoituksena olikin vertailla kroonisesta akillesjännekiputilasta kärsivien ja kontrollihenkilöiden aivoaktivaatio…
Consequential life cycle assessment of the Italian power system
2022
Energy production and consumption contribute to 76% of the European greenhouse gas (GHG) emissions in 2018, and 90% of global GHG emissions with land use, land use change and forestation (LULUCF) in the same year. By applying energy efficiency (EE) and renewable energy (RE) technologies, the GHG emission intensity of the energy sector reduced by 1.3% in 2018 compared to the previous year. The current climate change policy aims at decarbonization, sustainable environment, economic prosperity and social equity. It requires the deep decarbonisation of the economies, meaning that the energy and power systems as well as other emission intensive sectors need to transform into zero-emission ones. …
Proton dripline studies at ISOLDE: 31Ar and 9C
2002
In this contribution examples of the application of new technologies to disentangle the mechanism of beta-delayed multiparticle emission are given. In particular the mechanism of β-delayed two-proton emission from 31Ar has be resolved and proved to be sequential, a preview of 9C-decay data is discussed. peerReviewed