599 research outputs found

    Acoustic Bragg Peak Localization in Proton Therapy Treatment: Simulation Studies

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    [EN] A full chain simulation of the acoustic hadron therapy monitoring for brain tumors is presented in this work. For the study, a proton beam of 100 MeV was considered. In the first stage, Geant4 was used to simulate the energy deposition and to study the behavior of the Bragg peak. The energy deposition in the medium produced local heating that can be considered instantaneous with respect to the hydrodynamic time scale producing a sound pressure wave. The resulting thermoacoustic signal was subsequently obtained by solving the thermoacoustic equation. The acoustic propagation was simulated by the Finite Element Method (FEM) in the brain and the skull, where a set of piezoelectric sensors were placed. Lastly, the final received signals in the sensors were processed in order to reconstruct the position of the thermal source and, thus, to determine the feasibility and accuracy of acoustic beam monitoring in hadron therapy.Otero, J.; Felis, I.; Ardid Ramírez, M.; Herrero Debón, A.; Merchán, JA. (2019). Acoustic Bragg Peak Localization in Proton Therapy Treatment: Simulation Studies. MDPI. 1-7. https://doi.org/10.3390/ecsa-6-06533S1

    Bragg Peak Localization with Piezoelectric Sensors for Proton Therapy Treatment

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    [EN] A full chain simulation of the acoustic hadrontherapy monitoring for brain tumours is presented in this work. For the study, a proton beam of 100 MeV is considered. In the first stage, Geant4 is used to simulate the energy deposition and to study the behaviour of the Bragg peak. The energy deposition in the medium produces local heating that can be considered instantaneous with respect to the hydrodynamic time scale producing a sound pressure wave. The resulting thermoacoustic signal has been subsequently obtained by solving the thermoacoustic equation. The acoustic propagation has been simulated by FEM methods in the brain and the skull, where a set of piezoelectric sensors are placed. Last, the final received signals in the sensors have been processed in order to reconstruct the position of the thermal source and, thus, to determine the feasibility and accuracy of acoustic beam monitoring in hadrontherapy.This research received was funded by the Spanish Agencia Estatal de Investigacion, grant numbers FPA2015-65150-C3-2-P (MINECO/FEDER) and PGC2018-096663-B-C43 (MCIU/FEDER).Otero-Vega, JE.; Felis-Enguix, I.; Herrero Debón, A.; Merchán, JA.; Ardid Ramírez, M. (2020). Bragg Peak Localization with Piezoelectric Sensors for Proton Therapy Treatment. Sensors. 20(10):1-12. https://doi.org/10.3390/s20102987S1122010A population-based assessment of proton beam therapy utilization in California. (2020). The American Journal of Managed Care, 26(2), e28-e35. doi:10.37765/ajmc.2020.42398Dutz, A., Agolli, L., Bütof, R., Valentini, C., Baumann, M., Lühr, A., … Krause, M. (2020). Neurocognitive function and quality of life after proton beam therapy for brain tumour patients. Radiotherapy and Oncology, 143, 108-116. doi:10.1016/j.radonc.2019.12.024Lesueur, P., Calugaru, V., Nauraye, C., Stefan, D., Cao, K., Emery, E., … Thariat, J. (2019). Proton therapy for treatment of intracranial benign tumors in adults: A systematic review. Cancer Treatment Reviews, 72, 56-64. doi:10.1016/j.ctrv.2018.11.004Amaldi, U., Bonomi, R., Braccini, S., Crescenti, M., Degiovanni, A., Garlasché, M., … Zennaro, R. (2010). Accelerators for hadrontherapy: From Lawrence cyclotrons to linacs. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 620(2-3), 563-577. doi:10.1016/j.nima.2010.03.130Weber, D. C., Abrunhosa-Branquinho, A., Bolsi, A., Kacperek, A., Dendale, R., Geismar, D., … Grau, C. (2017). Profile of European proton and carbon ion therapy centers assessed by the EORTC facility questionnaire. Radiotherapy and Oncology, 124(2), 185-189. doi:10.1016/j.radonc.2017.07.012MIZUMOTO, M., OSHIRO, Y., YAMAMOTO, T., KOHZUKI, H., & SAKURAI, H. (2017). Proton Beam Therapy for Pediatric Brain Tumor. Neurologia medico-chirurgica, 57(7), 343-355. doi:10.2176/nmc.ra.2017-0003Sulak, L., Armstrong, T., Baranger, H., Bregman, M., Levi, M., Mael, D., … Learned, J. (1979). Experimental studies of the acoustic signature of proton beams traversing fluid media. Nuclear Instruments and Methods, 161(2), 203-217. doi:10.1016/0029-554x(79)90386-0Aso, T., Kimura, A., Tanaka, S., Yoshida, H., Kanematsu, N., Sasaki, T., & Akagi, T. (2005). Verification of the dose distributions with GEANT4 simulation for proton therapy. IEEE Transactions on Nuclear Science, 52(4), 896-901. doi:10.1109/tns.2005.852697Jones, K. C., Witztum, A., Sehgal, C. M., & Avery, S. (2014). Proton beam characterization by proton-induced acoustic emission: simulation studies. Physics in Medicine and Biology, 59(21), 6549-6563. doi:10.1088/0031-9155/59/21/6549Jones, K. C., Seghal, C. M., & Avery, S. (2016). How proton pulse characteristics influence protoacoustic determination of proton-beam range: simulation studies. Physics in Medicine and Biology, 61(6), 2213-2242. doi:10.1088/0031-9155/61/6/2213Donnelly, B. R., & Medige, J. (1997). Shear Properties of Human Brain Tissue. Journal of Biomechanical Engineering, 119(4), 423-432. doi:10.1115/1.2798289Gu, L., Chafi, M. S., Ganpule, S., & Chandra, N. (2012). The influence of heterogeneous meninges on the brain mechanics under primary blast loading. Composites Part B: Engineering, 43(8), 3160-3166. doi:10.1016/j.compositesb.2012.04.014Peterson, J., & Dechow, P. C. (2003). Material properties of the human cranial vault and zygoma. The Anatomical Record, 274A(1), 785-797. doi:10.1002/ar.a.10096Fellah, Z. E. A., Chapelon, J. Y., Berger, S., Lauriks, W., & Depollier, C. (2004). Ultrasonic wave propagation in human cancellous bone: Application of Biot theory. The Journal of the Acoustical Society of America, 116(1), 61-73. doi:10.1121/1.1755239Raffaele, L. (2016). Advances in hadrontherapy dosimetry. Physica Medica, 32, 187. doi:10.1016/j.ejmp.2016.07.323Dosanjh, M., Amaldi, U., Mayer, R., & Poetter, R. (2018). ENLIGHT: European network for Light ion hadron therapy. Radiotherapy and Oncology, 128(1), 76-82. doi:10.1016/j.radonc.2018.03.014Ahmad, M., Xiang, L., Yousefi, S., & Xing, L. (2015). Theoretical detection threshold of the proton-acoustic range verification technique. Medical Physics, 42(10), 5735-5744. doi:10.1118/1.4929939Smith, A., Gillin, M., Bues, M., Zhu, X. R., Suzuki, K., Mohan, R., … Matsuda, K. (2009). The M. D. Anderson proton therapy system. Medical Physics, 36(9Part1), 4068-4083. doi:10.1118/1.3187229Yock, T. I., & Tarbell, N. J. (2004). Technology Insight: proton beam radiotherapy for treatment in pediatric brain tumors. Nature Clinical Practice Oncology, 1(2), 97-103. doi:10.1038/ncponc0090Riva, M., Vallicelli, E. A., Baschirotto, A., & De Matteis, M. (2018). Acoustic Analog Front End for Proton Range Detection in Hadron Therapy. IEEE Transactions on Biomedical Circuits and Systems, 12(4), 954-962. doi:10.1109/tbcas.2018.2828703Acoustics Module User’s Guidehttps://doc.comsol.com/5.4/doc/com.comsol.help.aco/AcousticsModuleUsersGuide.pdfArdid, M., Felis, I., Martínez-Mora, J. A., & Otero, J. (2017). Optimization of Dimensions of Cylindrical Piezoceramics as Radio-Clean Low Frequency Acoustic Sensors. Journal of Sensors, 2017, 1-8. doi:10.1155/2017/8179672Otero, Felis, Ardid, & Herrero. (2019). Acoustic Localization of Bragg Peak Proton Beams for Hadrontherapy Monitoring. Sensors, 19(9), 1971. doi:10.3390/s19091971Levenberg, K. (1944). A method for the solution of certain non-linear problems in least squares. Quarterly of Applied Mathematics, 2(2), 164-168. doi:10.1090/qam/10666Geant4 A Simulation Toolkithttp://geant4-userdoc.web.cern.ch/geant4-userdoc/UsersGuides/ForApplicationDeveloper/BackupVersions/V10.5-2.0/fo/BookForApplicationDevelopers.pdfBarber, T. W., Brockway, J. A., & Higgins, L. S. (1970). THE DENSITY OF TISSUES IN AND ABOUT THE HEAD. Acta Neurologica Scandinavica, 46(1), 85-92. doi:10.1111/j.1600-0404.1970.tb05606.xAdrián-Martínez, S., Bou-Cabo, M., Felis, I., Llorens, C. D., Martínez-Mora, J. A., Saldaña, M., & Ardid, M. (2015). Acoustic Signal Detection Through the Cross-Correlation Method in Experiments with Different Signal to Noise Ratio and Reverberation Conditions. Lecture Notes in Computer Science, 66-79. doi:10.1007/978-3-662-46338-3_

    Comparison of a proprioceptive training program on stable base and unstable base

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    The aim is to compare two proprioceptive training programs on a stable (G1) and an unstable (G2) base in terms of balance and stability. During a 5 week period, 18 professional football players underwent a proprioceptive training program, 9 in G1 and the other 9 in G2. The Standard Excursion Balance Test was applied before and after the intervention program. Significant intragroup differences were found in the variables LEFT FRONT, ANTEROLATERAL LEFT (ANTLAT.LEFT), BACK RIGHT and ANTEROMEDIAL RIGHT (ANTMED.RIGHT) (p<0,005) for the G1, and FRONT RIGHT, FRONT LEFT, POSTMED.RIGHT, POSTMED.LEFT and MED.RIGHT (p <0,005) for G2. We conclude that there are no significant differences between the unstable base training and training stable base regarding improvement in balance and stability.Actividad Física y Deport

    Revisiting the neuropathology of sudden infant death syndrome (SIDS)

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    Background: Sudden infant death syndrome (SIDS) is one of the leading causes of infant mortality in the United States (US). The extent to which SIDS manifests with an underlying neuropathological mechanism is highly controversial. SIDS correlates with markers of poor prenatal and postnatal care, generally rooted in the lack of access and quality of healthcare endemic to select racial and ethnic groups, and thus can be viewed in the context of health disparities. However, some evidence suggests that at least a subset of SIDS cases may result from a neuropathological mechanism. To explain these issues, a triple-risk hypothesis has been proposed, whereby an underlying biological abnormality in an infant facing an extrinsic risk during a critical developmental period SIDS is hypothesized to occur. Each SIDS decedent is thus thought to have a unique combination of these risk factors leading to their death. This article reviews the neuropathological literature of SIDS and uses machine learning tools to identify distinct subtypes of SIDS decedents based on epidemiological data. Methods: We analyzed US Period Linked Birth/Infant Mortality Files from 1990 to 2017 (excluding 1992–1994). Using t-SNE, an unsupervised machine learning dimensionality reduction algorithm, we identified clusters of SIDS decedents. Following identification of these groups, we identified changes in the rates of SIDS at the state level and across three countries. Results: Through t-SNE and distance based statistical analysis, we identified three groups of SIDS decedents, each with a unique peak age of death. Within the US, SIDS is geographically heterogeneous. Following this, we found low birth weight and normal birth weight SIDS rates have not been equally impacted by implementation of clinical guidelines. We show that across countries with different levels of cultural heterogeneity, reduction in SIDS rates has also been distinct between decedents with low vs. normal birth weight. Conclusions: Different epidemiological and extrinsic risk factors exist based on the three unique SIDS groups we identified with t-SNE and distance based statistical measurements. Clinical guidelines have not equally impacted the groups, and normal birth weight infants comprise more of the cases of SIDS even though low birth weight infants have a higher SIDS rate.Fil: Blackburn, Jessica. The Ohio State University College Of Medicine; Estados UnidosFil: Chapur, Valeria Fernanda. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; Argentina. Universidad Nacional de Jujuy. Instituto de Biología de la Altura; ArgentinaFil: Stephens, Julie A.. The Ohio State University College Of Medicine; Estados UnidosFil: Zhao, Jing. The Ohio State University College Of Medicine; Estados UnidosFil: Shepler, Anne. The Ohio State University College Of Medicine; Estados UnidosFil: Pierson, Christopher R.. The Ohio State University College Of Medicine; Estados UnidosFil: Otero, José Javier. The Ohio State University College Of Medicine; Estados Unido

    Fiabilidad de las pruebas de fuerza en salto vertical y velocidad de carrera en escolares de 6 a 8 años

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    El objetivo del presente estudio fue determinar la fiabilidad de diversas pruebas de salto vertical y de carrera rápida en escolares de 6 a 8 años. Participaron 56 sujetos de ambos sexos (30 niñas y 26 niños), de edades comprendidas entre 6 y 8 años, seleccionados aleatoriamente entre los de un mismo centro escolar, a los que se administró una batería de pruebas de fuerza de salto vertical sobre plataforma de contactos (SJ, CMJ, CMJA y 1RJ) y de carrera rápida (30 m) en dos ocasiones (T1 y T2), con una semana de intervalo entre ambas. Se estudió la reproducibilidad entre repeticiones (variabilidad intraindividual) para cada una de las dos sesiones de valoración (T1, T2) y la variabilidad temporal (entre T1 y T2), mediante el cálculo de diferentes estadísticos (coeficiente de variación, CV; coeficiente de correlación intraclase, CCI; error metódico, EM) y de su significación estadística. La reproducibilidad entre repeticiones de las pruebas de salto vertical CMJ y 1RJ se demostró elevada (CCI 0,95) en ambas sesiones. En la segunda sesión de valoración también lo fue la reproducibilidad de SJ, mientras que CMJA se mantuvo en niveles inaceptables (CCI = 0,69-0,80). La variabilidad entre sujetos se mostró bastante más elevada que en estudiantes de educación física adultos (CV = 8,3-11,8 %). La reproducibilidad temporal (día a día, entre dos sesiones separadas por una semana) de las pruebas puede considerarse cuestionable en términos generales, observándose un elevado error metódico (EM = 9,9-15,1 %) y un empeoramiento significativo de los resultados en la segunda sesión en las pruebas de salto con contramovimiento (CMJ y CMJA) y de carrera rápida de 30 m (p 0,05). En función de los resultados se proponen algunas medidas conducentes a la mejora de la fiabilidad de las pruebas

    Determination of Sr-90 in milk samples from the study of statistical results

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    [Abstract] The determination of 90Sr in milk samples is the main objective of radiation monitoring laboratories because of its environmental importance. In this paper the concentration of activity of 39 milk samples was obtained through radiochemical separation based on selective retention of Sr in a cationic resin (Dowex 50WX8, 50-100 mesh) and subsequent determination by a low-level proportional gas counter. The results were checked by performing the measurement of the Sr concentration by using the flame atomic absorption spectroscopy technique, to finally obtain the mass of 90Sr. From the data obtained a statistical treatment was performed using linear regressions. A reliable estimate of the mass of 90Sr was obtained based on the gravimetric technique, and secondly, the counts per minute of the third measurement in the 90Sr and 90Y equilibrium, without having to perform the analysis. These estimates have been verified with 19 milk samples, obtaining overlapping results. The novelty of the manuscript is the possibility of determining the concentration of 90Sr in milk samples, without the need to perform the third measurement in the equilibrium

    Recommendations for vaccination in patients with multiple sclerosis who are eligible for immunosuppressive therapies: Spanish consensus statement

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    Esclerosis múltiple; Vacunación; ConsensoEsclerosi múltiple; Vacunació; ConsensMultiple sclerosis; Vaccination; ConsensusAntecedentes La reciente aparición de terapias de alta efectividad para el tratamiento de la esclerosis múltiple (EM), con potencial riesgo de complicaciones infecciosas, obliga plantear estrategias de prevención y minimización de riesgos. La vacunación constituye una parte esencial del manejo de estos pacientes. Este consenso recoge una serie de pautas y escenarios prácticos de vacunación en pacientes adultos con EM candidatos a tratamiento inmunosupresor. Metodología Se llevó a cabo un consenso de tipo formal. Tras definir el alcance del documento, se realizó una búsqueda bibliográfica de vacunación en pacientes con EM, así como guías de vacunación específicas de pacientes inmunosuprimidos y en tratamiento biológico con otras enfermedades. Para la formulación de las recomendaciones se empleó la metodología de Modified Nominal Group Technique. Desarrollo La vacunación en pacientes candidatos a tratamiento inmunosupresor se debe plantear antes de iniciar un tratamiento inmunosupresor siempre que la situación clínica del paciente lo permita. Se recomendarán tanto aquellas indicadas en el calendario vacunal del adulto, como algunas específicas, en función de la inmunidad previa. Si ya está instaurado el tratamiento inmunosupresor las vacunas vivas atenuadas estarán contraindicadas. Para aquellas vacunas que dispongan de un correlato de protección se recomienda monitorizar la respuesta serológica transcurridos de uno a 2 meses de la última dosis.Background The recent development of highly effective treatments for multiple sclerosis (MS) and the potential risk of infectious complications require the development of prevention and risk minimisation strategies. Vaccination is an essential element of the management of these patients. This consensus statement includes a series of recommendations and practical scenarios for the vaccination of adult patients with MS who are eligible for highly effective immunosuppressive treatments. Methodology A formal consensus procedure was followed. Having defined the scope of the statement, we conducted a literature search on recommendations for the vaccination of patients with MS and specific vaccination guidelines for immunosuppressed patients receiving biological therapy for other conditions. The modified nominal group technique methodology was used to formulate the recommendations. Development Vaccination in patients who are candidates for immunosuppressive therapy should be considered before starting immunosuppressive treatment providing the patient's clinical situation allows. Vaccines included in the routine adult vaccination schedule, as well as some specific ones, are recommended depending on the pre-existing immunity status. If immunosuppressive treatment is already established, live attenuated vaccines are contraindicated. For vaccines with a correlate of protection, it is recommended to monitor the serological response in an optimal interval of 1-2 months from the last dose

    Populism and hegemony in Islamic State: The building of the caliphal State in the propagandistic Dabiq magazine

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    This paper studies the form and emergence of the construction and representation of the self-proclamed State of caliphate by Islamic State. Dabiq magazine, the bridge between the organization and its readers (allies and enemies) has been used completely in this paper (15 total issues) with the purpose of knowing and comprehending critically how ISIS uses a propagandist and its communicative line to construct and represent itself and its idea of State as safe and pious. Great quality visual and textual resources of the magazine reproduce the populist, hegemonic and antagonistic self-construction of the caliphate as a form of life and government. It will also show the self-projection of ISIS to the outside and the we-other equation. In short, this work aims to approach the propagandistic discourse of an organization that shapes itself as the savior of society, designed and self-proclaimed through social institutions and forms of government that reinforce its domination and particular cultural hegemony.El presente estudio analiza la construcción y de la representación del califato como Estado por parte del Estado Islámico. Para ello, se ha utilizado la revista Dabiq al completo. En el análisis se establecerá la forma en la que ISIS se autoproyecta hacia el exterior, incidiendo sobre todo en la ecuación nosotros-otros y nutriéndose de los imaginarios sociales y colectivos allegados a esta. En definitiva, este trabajo pretende acercarse al instrumento propagandístico de una organización que se plasma a sí misma como la salvadora de la sociedad y que, por ende, se ha diseñado y autoproclamado a través de unas instituciones sociales y unas formas de gobierno que refuerzan esa hegemonía cultural particular

    Behaviour of Non-O157 STEC and Atypical EPEC during the Manufacturing and Ripening of Raw Milk Cheese

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    12 p.This study was carried out to assess the survival of Shiga toxin-producing E. coli (STEC) and atypical enteropathogenic Escherichia coli (aEPEC) during the traditional manufacturing and ripening of Spanish hard cheese from raw cow’s milk. Milk samples were spiked with up to 3.1–3.5 log cfu/mL of one strain of STEC (O140:H32 serotype) and one of aEPEC (serotype O25:H2). The first steps of cheesemaking allow for a STEC and aEPEC increase of more than 1 log cfu/mL (up to 4.74 log cfu/g and 4.55 log cfu/g, respectively). After cheese pressing, a steady reduction of both populations was observed, with the STEC strain being more sensitive. The studied pathogenic E. coli populations decreased by 1.32 log cfu/g in STEC and 0.59 log cfu/g in aEPEC in cheese ripened during a minimum period of 60 d. Therefore, a moderate contamination by these diarrhoeagenic E. coli pathotypes, in particular, with aEPEC, on cheese manufactured from raw milk may not be totally controlled through the cheesemaking process and during a maturation of 90 d. These findings remark the importance of improvement in bacteriological quality of raw milk and crosscontamination prevention with diarrhoeagenic E. coli in the dairy industryS
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