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Author Di Gregorio, E.; Staelens, M.; Hosseinkhah, N.; Karimpoor, M.; Liburd, J.; Lim, L.; Shankar, K.; Tuszynski, J.A.
Title Raman Spectroscopy Reveals Photobiomodulation-Induced α-Helix to β-Sheet Transition in Tubulins: Potential Implications for Alzheimer's and Other Neurodegenerative Diseases Type Journal Article
Year 2024 Publication Nanomaterials Abbreviated Journal (down) Nanomaterials
Volume 14 Issue 13 Pages 1093 - 21pp
Keywords proteins; protein dynamics; protein structure; non-invasive therapies; low-level laser therapy; spectroscopy; amide bands; amide I; spectral decomposition
Abstract In small clinical studies, the application of transcranial photobiomodulation (PBM), which typically delivers low-intensity near-infrared (NIR) to treat the brain, has led to some remarkable results in the treatment of dementia and several neurodegenerative diseases. However, despite the extensive literature detailing the mechanisms of action underlying PBM outcomes, the specific mechanisms affecting neurodegenerative diseases are not entirely clear. While large clinical trials are warranted to validate these findings, evidence of the mechanisms can explain and thus provide credible support for PBM as a potential treatment for these diseases. Tubulin and its polymerized state of microtubules have been known to play important roles in the pathology of Alzheimer's and other neurodegenerative diseases. Thus, we investigated the effects of PBM on these cellular structures in the quest for insights into the underlying therapeutic mechanisms. In this study, we employed a Raman spectroscopic analysis of the amide I band of polymerized samples of tubulin exposed to pulsed low-intensity NIR radiation (810 nm, 10 Hz, 22.5 J/cm2 dose). Peaks in the Raman fingerprint region (300-1900 cm-1)-in particular, in the amide I band (1600-1700 cm-1)-were used to quantify the percentage of protein secondary structures. Under this band, hidden signals of C=O stretching, belonging to different structures, are superimposed, producing a complex signal as a result. An accurate decomposition of the amide I band is therefore required for the reliable analysis of the conformation of proteins, which we achieved through a straightforward method employing a Voigt profile. This approach was validated through secondary structure analyses of unexposed control samples, for which comparisons with other values available in the literature could be conducted. Subsequently, using this validated method, we present novel findings of statistically significant alterations in the secondary structures of polymerized NIR-exposed tubulin, characterized by a notable decrease in alpha-helix content and a concurrent increase in beta-sheets compared to the control samples. This PBM-induced alpha-helix to beta-sheet transition connects to reduced microtubule stability and the introduction of dynamism to allow for the remodeling and, consequently, refreshing of microtubule structures. This newly discovered mechanism could have implications for reducing the risks associated with brain aging, including neurodegenerative diseases like Alzheimer's disease, through the introduction of an intervention following this transition.
Address [Di Gregorio, Elisabetta; Staelens, Michael; Tuszynski, Jack A.] Univ Alberta, Fac Sci, Dept Phys, Edmonton, AB T6G 2E1, Canada, Email: michael.staelens@ific.uv.es
Corporate Author Thesis
Publisher Mdpi Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes WOS:001269841000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6204
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Author Piriz, G.H.; Gonzalez-Sprinberg, G.A.; Ballester, F.; Vijande, J.
Title Dosimetry of Large Field Valencia applicators for Cobalt-60-based brachytherapy Type Journal Article
Year 2024 Publication Medical Physics Abbreviated Journal (down) Med. Phys.
Volume 51 Issue Pages 5094-5098
Keywords dosimetry; Monte Carlo; skin brachytherapy; Valencia applicators
Abstract BackgroundNon-melanoma skin cancer is one of the most common types of cancer and one of the main approaches is brachytherapy. For small lesions, the treatment of this cancer with brachytherapy can be done with two commercial applicators, one of these is the Large Field Valencia Applicators (LFVA).PurposeThe aim of this study is to test the capabilities of the LFVA to use clinically 60Co sources instead of the 192Ir ones. This study was designed for the same dwell positions and weights for both sources.MethodsThe Penelope Monte Carlo code was used to evaluate dose distribution in a water phantom when a 60Co source is considered. The LFVA design and the optimized dwell weights reported for the case of 192Ir are maintained with the only exception of the dwell weight of the central position, that was increased. 2D dose distributions, field flatness, symmetry and the leakage dose distribution around the applicator were calculated.ResultsWhen comparing the dose distributions of both sources, field flatness and symmetry remain unchanged. The only evident difference is an increase of the penumbra regions for all depths when using the 60Co source. Regarding leakage, the maximum dose within the air volume surrounding the applicator is in the order of 20% of the prescription dose for the 60Co source, but it decreases to less than 5% at about 1 cm distance.ConclusionsFlatness and symmetry remains unaltered as compared with 192Ir sources, while an increase in leakage has been observed. This proves the feasibility of using the LFVA in a larger range of clinical applications.
Address [Piriz, Gustavo H.; Gonzalez-Sprinberg, Gabriel A.] Univ Republica, Fac Sci, Med Phys Unit, Montevideo, Uruguay, Email: ghpiriz@gmail.com
Corporate Author Thesis
Publisher Wiley Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0094-2405 ISBN Medium
Area Expedition Conference
Notes WOS:001187737100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6011
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Author Mata, R.; Cros, A.; Gimeno, B.; Raboso, D.
Title Secondary electron emission yield in thick dielectric materials: a comparison between Kelvin probe and capacitive methods Type Journal Article
Year 2024 Publication Journal of Physics D Abbreviated Journal (down) J. Phys. D
Volume 57 Issue 40 Pages 405302 - 9pp
Keywords dielectrics; secondary electron emission yield; Multipactor in space devices
Abstract The recent high demand of secondary electron emission yield (SEY) measurements in dielectric materials from space industry has driven SEY laboratories to improve their facilities and measurement techniques. SEY determination by the common capacitive method, also known as pulsed method, is well accepted and has given satisfactory results in most cases. Nevertheless, the samples under study must be prepared according to the experimental limitations of the technique, i.e. they should be manufactured separated from the devices representing faithfully the surface state of the own device and be as thin as possible. A method based on the Kelvin probe (KP) is proposed here to obtain the SEY characteristics of electrically floating Platinum, Kapton and Teflon placed over dielectric spacers with thicknesses ranging from 1.6 to 12.1 mm. The results are compared with those of the capacitive method and indicate that KP SEY curves are less sensitive to spacer thickness. An explanation based on the literature is also given. In all, we have established that KP is better suited for the analysis of dielectric samples thicker than 3 mm.
Address [Mata, R.; Gimeno, B.] Ciudad Politecn Innovac, Val Space Consortium, Edificio 8G,Acceso B,Planta B, Valencia 46022, Spain, Email: rafael.mata@uv.es
Corporate Author Thesis
Publisher IOP Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727 ISBN Medium
Area Expedition Conference
Notes WOS:001269188200001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6203
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Author Martins, A.; da Mota, A.F.; Stanford, C.; Contreras, T.; Martin-Albo, J.; Kish, A.; Escobar, C.O.; Para, A.; Guenette, R.
Title Simple strategy for the simulation of axially symmetric large-area metasurfaces Type Journal Article
Year 2024 Publication Journal of the Optical Society of America B Abbreviated Journal (down) J. Opt. Soc. Am. B
Volume 41 Issue 5 Pages 1261-1269
Keywords
Abstract Metalenses are composed of nanostructures for focusing light and have been widely explored in many exciting applications. However, their expanding dimensions pose simulation challenges. We propose a method to simulate metalenses in a timely manner using vectorial wave and ray tracing models. We sample the metalens's radial phase gradient and locally approximate the phase profile by a linear phase response. Each sampling point is modeled as a binary blazed grating, employing the chosen nanostructure, to build a transfer function set. The metalens transmission or reflection is then obtained by applying the corresponding transfer function to the incoming field on the regions surrounding each sampling point. Fourier optics is used to calculate the scattered fields under arbitrary illumination for the vectorial wave method, and a Monte Carlo algorithm is used in the ray tracing formalism. We validated our method against finite -difference time domain simulations at 632 nm, and we were able to simulate metalenses larger than 3000 wavelengths in diameter on a personal computer.
Address [Martins, Augusto; Guenette, Roxanne] Univ Manchester, Dept Phys, Manchester M13 9PL, England, Email: augusto.martins@york.ac.uk
Corporate Author Thesis
Publisher Optica Publishing Group Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0740-3224 ISBN Medium
Area Expedition Conference
Notes WOS:001237140900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6140
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Author ATLAS Collaboration (Abat, E. et al); Bernabeu Verdu, J.; Castillo Gimenez, V.; Costa, M.J.; Escobar, C.; Ferrer, A.; Garcia, C.; Gonzalez-Sevilla, S.; Higon-Rodriguez, E.; Lacasta, C.; Marti-Garcia, S.; Mitsou, V.A.; Ruiz, A.; Solans, C.; Valero, A.; Valls Ferrer, J.A.
Title Combined performance studies for electrons at the 2004 ATLAS combined test-beam Type Journal Article
Year 2010 Publication Journal of Instrumentation Abbreviated Journal (down) J. Instrum.
Volume 5 Issue Pages P11006 - 68pp
Keywords Particle tracking detectors; Transition radiation detectors; Calorimeters; Large detector systems for particle and astroparticle physics
Abstract In 2004 at the ATLAS (A Toroidal LHC ApparatuS) combined test beam, one slice of the ATLAS barrel detector (including an Inner Detector set-up and the Liquid Argon calorimeter) was exposed to particles from the H8 SPS beam line at CERN. It was the first occasion to test the combined electron performance of ATLAS. This paper presents results obtained for the momentum measurement p with the Inner Detector and for the performance of the electron measurement with the LAr calorimeter (energy E linearity and resolution) in the presence of a magnetic field in the Inner Detector for momenta ranging from 20 GeV/c to 100 GeV/c. Furthermore the particle identification capabilities of the Transition Radiation Tracker, Bremsstrahlungs-recovery algorithms relying on the LAr calorimeter and results obtained for the E/p ratio and a way how to extract scale parameters will be discussed.
Address Univ Alberta, Ctr Particle Phys, Dept Phys, Edmonton, AB T6G 2G7, Canada, Email: robert.froesch1@cern.ch
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1748-0221 ISBN Medium
Area Expedition Conference
Notes ISI:000285051500031 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 311
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Author ATLAS Collaboration (Abat, E. et al); Bernabeu Verdu, J.; Castillo Gimenez, V.; Costa, M.J.; Escobar, C.; Ferrer, A.; Garcia, C.; Gonzalez-Sevilla, S.; Higon-Rodriguez, E.; Lacasta, C.; Marti-Garcia, S.; Mitsou, V.A.; Ruiz, A.; Solans, C.; Valero, A.; Valls Ferrer, J.A.
Title A layer correlation technique for pion energy calibration at the 2004 ATLAS Combined Beam Test Type Journal Article
Year 2011 Publication Journal of Instrumentation Abbreviated Journal (down) J. Instrum.
Volume 6 Issue Pages P06001 - 35pp
Keywords Calorimeter methods; Pattern recognition, cluster finding, calibration and fitting methods; Calorimeters; Detector modelling and simulations I (interaction of radiation with matter, interaction of photons with matter, interaction of hadrons with matter, etc)
Abstract A new method for calibrating the hadron response of a segmented calorimeter is developed and successfully applied to beam test data. It is based on a principal component analysis of energy deposits in the calorimeter layers, exploiting longitudinal shower development information to improve the measured energy resolution. Corrections for invisible hadronic energy and energy lost in dead material in front of and between the calorimeters of the ATLAS experiment were calculated with simulated Geant4 Monte Carlo events and used to reconstruct the energy of pions impinging on the calorimeters during the 2004 Barrel Combined Beam Test at the CERN H8 area. For pion beams with energies between 20 GeV and 180 GeV, the particle energy is reconstructed within 3% and the energy resolution is improved by between 11% and 25% compared to the resolution at the electromagnetic scale.
Address [Wheeler, S] Univ Alberta, Dept Phys, Ctr Particle Phys, Edmonton, AB T6G 2G7, Canada[Bernabeu, J; Castillo, MV; Costa, MJ; Escobar, C; Ferrer, A; Garcia, C; Gonzalez-Sevilla, S; Higon, E; Lacasta, C; Garcia, SMI; Mitsou, VA; Ruiz, A; Solans, C; Valero, A; Valls, JA] Ctr Mixto UVEG CSIC, Inst Fis Corpuscular IFIC, ES-46071 Valencia, Spain, Email: kjg@particle.kth.se
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1748-0221 ISBN Medium
Area Expedition Conference
Notes WOS:000294492600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 744
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Author ATLAS Collaboration (Abat, E. et al); Bernabeu Verdu, J.; Castillo Gimenez, V.; Costa, M.J.; Escobar, C.; Ferrer, A.; Garcia, C.; Gonzalez-Sevilla, S.; Higon-Rodriguez, E.; Lacasta, C.; Marti-Garcia, S.; Mitsou, V.A.; Ruiz, A.; Solans, C.; Valero, A.; Valls Ferrer, J.A.
Title Photon reconstruction in the ATLAS Inner Detector and Liquid Argon Barrel Calorimeter at the 2004 Combined Test Beam Type Journal Article
Year 2011 Publication Journal of Instrumentation Abbreviated Journal (down) J. Instrum.
Volume 6 Issue Pages P04001 - 40pp
Keywords Transition radiation detectors; Calorimeters; Large detector systems for particle and astroparticle physics; Particle tracking detectors (Solid-state detectors)
Abstract The reconstruction of photons in the ATLAS detector is studied with data taken during the 2004 Combined Test Beam, where a full slice of the ATLAS detector was exposed to beams of particles of known energy at the CERN SPS. The results presented show significant differences in the longitudinal development of the electromagnetic shower between converted and unconverted photons as well as in the total measured energy. The potential to use the reconstructed converted photons as a means to precisely map the material of the tracker in front of the electromagnetic calorimeter is also considered. All results obtained are compared with a detailed Monte-Carlo simulation of the test-beam setup which is based on the same simulation and reconstruction tools as those used for the ATLAS detector itself.
Address [Wheeler, S.] Univ Alberta, Dept Phys, Ctr Particle Phys, Edmonton, AB T6G 2G7, Canada, Email: stathes.paganis@cern.ch
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1748-0221 ISBN Medium
Area Expedition Conference
Notes WOS:000294491300002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 848
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Author Bates, R.L. et al; Bernabeu Verdu, J.; Civera, J.V.; Gonzalez, F.; Lacasta, C.; Sanchez, J.
Title The ATLAS SCT grounding and shielding concept and implementation Type Journal Article
Year 2012 Publication Journal of Instrumentation Abbreviated Journal (down) J. Instrum.
Volume 7 Issue Pages P03005
Keywords
Abstract This paper describes the design and implementation of the grounding and shielding system for the ATLAS SemiConductor Tracker (SCT). The mitigation of electromagnetic interference and noise pickup through power lines is the critical design goal as they have the potential to jeopardize the electrical performance. We accomplish this by adhering to the ATLAS grounding rules, by avoiding ground loops and isolating the different subdetectors. Noise sources are identified and design rules to protect the SCT against them are described. A rigorous implementation of the design was crucial to achieve the required performance. This paper highlights the location, connection and assembly of the different components that affect the grounding and shielding system: cables, filters, cooling pipes, shielding enclosure, power supplies and others. Special care is taken with the electrical properties of materials and joints. The monitoring of the grounding system during the installation period is also discussed. Finally, after connecting more than four thousand SCT modules to all of their services, electrical, mechanical and thermal within the wider ATLAS experimental environment, dedicated tests show that noise pickup is minimised.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1748-0221 ISBN Medium
Area Expedition Conference
Notes WOS:000304015300053 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1025
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Author Gonzalez-Sevilla, S. et al; Bernabeu Verdu, J.; Civera, J.V.; Garcia, C.; Lacasta, C.; Marco, R.; Marti-Garcia, S.; Santoyo, D.; Soldevila, U.
Title A double-sided silicon micro-strip Super-Module for the ATLAS Inner Detector upgrade in the High-Luminosity LHC Type Journal Article
Year 2014 Publication Journal of Instrumentation Abbreviated Journal (down) J. Instrum.
Volume 9 Issue Pages P02003 - 37pp
Keywords Particle tracking detectors; Si microstrip and pad detectors; Performance of High Energy Physics Detectors
Abstract The ATLAS experiment is a general purpose detector aiming to fully exploit the discovery potential of the Large Hadron Collider (LHC) at CERN. It is foreseen that after several years of successful data-taking, the LHC physics programme will be extended in the so-called High-Luminosity LHC, where the instantaneous luminosity will be increased up to 5 x 10(34) cm(-2) s(-1). For ATLAS, an upgrade scenario will imply the complete replacement of its internal tracker, as the existing detector will not provide the required performance due to the cumulated radiation damage and the increase in the detector occupancy. The current baseline layout for the new ATLAS tracker is an all-silicon-based detector, with pixel sensors in the inner layers and silicon micro-strip detectors at intermediate and outer radii. The super-module is an integration concept proposed for the strip region of the future ATLAS tracker, where double-sided stereo silicon micro-strip modules are assembled into a low-mass local support structure. An electrical super-module prototype for eight double-sided strip modules has been constructed. The aim is to exercise the multi-module readout chain and to investigate the noise performance of such a system. In this paper, the main components of the current super-module prototype are described and its electrical performance is presented in detail.
Address [Gonzalez-Sevilla, S.; Barbier, G.; Cadoux, F.; Clark, A.; Favre, Y.; Ferrere, D.; Iacobucci, G.; La Marra, D.; Weber, M.] DPNC Univ Geneva, Geneva, Switzerland, Email: rgio.Gonzalez.Sevilla@cern.ch
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1748-0221 ISBN Medium
Area Expedition Conference
Notes WOS:000332314400038 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1749
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Author Diez, S. et al; Bernabeu Verdu, J.; Civera, J.V.; Garcia, C.; Garcia-Argos, C.; Lacasta, C.; Marco, R.; Marti-Garcia, S.; Santoyo, D.; Soldevila, U.
Title A double-sided, shield-less stave prototype for the ATLAS Upgrade strip tracker for the High Luminosity LHC Type Journal Article
Year 2014 Publication Journal of Instrumentation Abbreviated Journal (down) J. Instrum.
Volume 9 Issue Pages P03012 - 16pp
Keywords Large detector-systems performance; Si microstrip and pad detectors; Particle tracking detectors; Performance of High Energy Physics Detectors
Abstract A detailed description of the integration structures for the barrel region of the silicon strips tracker of the ATLAS Phase-II upgrade for the upgrade of the Large Hadron Collider, the so-called High Luminosity LHC (HL-LHC), is presented. This paper focuses on one of the latest demonstrator prototypes recently assembled, with numerous unique features. It consists of a shortened, shield-less, and double sided stave, with two candidate power distributions implemented. Thermal and electrical performances of the prototype are presented, as well as a description of the assembly procedures and tools.
Address [Diez, S.; Haber, C. H.; Witharm, R.] LBNL, Berkeley, CA 94103 USA, Email: sdiezcornell@lbl.gov
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1748-0221 ISBN Medium
Area Expedition Conference
Notes WOS:000336123200072 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1802
Permanent link to this record