Jose Medina - Academia.edu (original) (raw)

Papers by Jose Medina

The British Journal of Radiology, 2016

Squamous cell carcinoma is the most common malignant tumour of the head and neck. The initial TNM... more Squamous cell carcinoma is the most common malignant tumour of the head and neck. The initial TNM staging, the evaluation of the tumour response during treatment, and the long-term surveillance are crucial moments in the approach to head and neck squamous cell carcinoma (HNSCC). Thus, at each of these moments, the choice of the best diagnostic tool providing the more precise and larger information is crucial. Positron emission tomography with fluorine-18 fludeoxyglucose integrated with CT (18 F-FDG-PET/CT) rapidly gained clinical acceptance, and it has become an important imaging tool in routine clinical oncology. However, controversial data are currently available, for example, on the role of 18 F-FDG-PET/CT imaging during radiotherapy planning, the prognostic value or its real clinical impact on treatment decisions. In this article, the role of 18 F-FDG-PET/CT imaging in HNSCC during pre-treatment staging, radiotherapy planning, treatment response assessment, prognosis and follow-up is reviewed focusing on current evidence and controversial issues. A proposal on how to integrate 18 F-FDG-PET/CT in daily clinical practice is also described.

Mitochondrial …, 2000

0 2000 OPA (Overseas Publishers Association) NV Published by license under the Harwood Academic P... more 0 2000 OPA (Overseas Publishers Association) NV Published by license under the Harwood Academic Publishers imprint, part of the Gordon and Breach Publishing Grnup. Printed m Malaysia ... A Bac Library and Paired-PCR Approach to Mapping ... QUNXIN SHE^, FABRICE ...

2016 IEEE Ecuador Technical Chapters Meeting (ETCM), 2016

Este documento contiene información de prueba. Contáctese con el administrador del Centro para el... more Este documento contiene información de prueba. Contáctese con el administrador del Centro para el acceso al documento originar del registro.

Revista Apd Asociacion Para El Progreso De La Direccion, 2007

The PESCA Instrument has been designed and built with the purpose of studying the Solar Energetic... more The PESCA Instrument has been designed and built with the purpose of studying the Solar Energetic Particles and the Anomalous Cosmic Rays from hydrogen to iron in the energy range 1.5-50 MeV/uma. The instrument will be part of the Russian PHOTON satellite payload. The instrument electronics system comprises two blocks: the analog block for the amplification process and the digital block for the data acquisition process. The hardware is based on MAS281 microprocessor and consists of two units, nominal and redundant, in order to prevent faults. The software and hardware control system are described. The PESCA Instrument comprises a detector telescope, which consists of 4 ion implanted silicon detectors, an analog electronics for the pulses amplification, and a digital electronics for the instrument control. The instrument will be part of the Russian PHOTON satellite payload, which is to be launched in 2001. A detailed description of the telescope and of the analog electronics (AE) has...

ABSTRACT Trying to get light in the paradigm of forecasting geomagnetic activity, we have tried t... more ABSTRACT Trying to get light in the paradigm of forecasting geomagnetic activity, we have tried to explain the physical processes that are involved in the interaction of magnetic clouds and the terrestrial ring current. This ring current consists of energetic charged particles flowing toroidally around the Earth. Changes in this current are responsible for global decreases in the Earth's surface magnetic fields, which is the defining feature of geomagnetric storms. In order to check our theoretical results, we have related the geomagnetic storms of years 1995-2000 (from minimum to maximum activity) with its precursor in the solar wind. When we have identified a MC as the solar wind precursor we have analyzed the solar wind even using a model that we have previously developed and that provides the orientation of its helicity. We have related these physical parameters (and others from the solar wind) with Dst index, as a geoeffectiveness indicator. On the basis of the results obtained, we show that there is close relationship between the helicity and orientation of a magnetic cloud, and the geoeffectiveness of the event.

Proceedings of the 2007 ACM SIGGRAPH symposium on Video games - Sandbox '07, 2007

... Victor Zordan, Adriano Macchietto, Jose Medina, Marc Soriano, Chun-Chih Wu∗ Riverside Graphic... more ... Victor Zordan, Adriano Macchietto, Jose Medina, Marc Soriano, Chun-Chih Wu∗ Riverside Graphics Lab Computer Science and Engineering University of ... characters to several other approaches that employ physically based motion edit-ing [Popovic and Witkin 1999; Abe et al. ...

Il Nuovo Cimento C, 1990

We have measured the elemental composition and mean masses of the cosmic rays from calcium to nic... more We have measured the elemental composition and mean masses of the cosmic rays from calcium to nickel using a Lexan polycarbonate stack exposed in a balloon flight. We obtain a 3% charge resolution for iron at an energy interval of (255-545) MeV/nucleon at the top of the atmosphere. We have propagated the spectrum measured through the detector, the residual atmosphere, the solar cavity and the interstellar medium, obtaining the composition at sources with a 7% resolution for iron. We observe that it is not possible to resolve adjacent isotopes with the Lexan polycarbonate.

ABSTRACT We present energetic particle data measured by COSTEP experiment aboard SoHO spacecraft ... more ABSTRACT We present energetic particle data measured by COSTEP experiment aboard SoHO spacecraft during the last Gnevysev gap (i.e. during the last solar magnetic field polarity reversal). We have focused our attention on the search of anomalous low particle fluxes during that time. Two periods with anomalous (low) energetic particle fluxes have been identified. Those periods show "common" solar/coronal features mainly related with low or very low number of CMEs and X-rays flares. We also describe the interplanetary phenomena that were detected during those periods.

Local variability of the Heliospheric Current Sheet (HCS) has been studied. Its local magnetic st... more Local variability of the Heliospheric Current Sheet (HCS) has been studied. Its local magnetic structure is observed as a boundary through which the magnetic field inverts its direction toward or away from Sun. In this work, we have used data from ACE, WIND, STEREO A and B spacecrafts. Solar wind features and magnetic field variations obtained from each spacecraft and for each event analyzed have been used to estimate temporal and spatial dependences in the local HCS structure. Their connection with the neutral line at the corona has been also determined. We have grouped the selected events according to their magnetic connection, with the aim of analyzing possible variations on the local orientation. Events studied cover from the ascending phase of solar cycle 23 to the next minimum around 2007. It has been observed that when spacecrafts are close to each other and/or magnetically well connected, clear variations on the local orientation are not observed. In these cases, the elapsed...

Pediatric Pulmonology, 2007

To analyze the initial experience in mechanical ventilation courses held by the Respiratory Group... more To analyze the initial experience in mechanical ventilation courses held by the Respiratory Group of the Spanish Paediatric Intensive Care Society. Materials and methods: From 2002 to 2006, 15 courses on paediatric mechanical ventilation were held in eight hospitals in Spain, attended by a total of 367 physicians (53.4 % trainees and 46.6 % staff physicians from Paediatrics, Neonatology or Emergency). An initial theoretical written test of 40 questions was completed by participants, followed by short theory classes and practical workshops based on clinical situations, with ventilators and ventilation simulators, with five to seven students per workshop. At the end of the course participants completed a theoretical written test, in which it was considered necessary to answer correctly at least 70% of the questions, a practical evaluation (with assessment grades from 1 to 5) and a written survey about the quality of the course (with assessment grades from 0 to 10). Results: In the initial test, only 20% of students answered 70% of questions correctly, whilst in the final test 93% hit this target, (p < 0.001). In the practical evaluation, 96% of students demonstrated sufficient acquisition of practical skills (grades equal to or greater than 3). In the participant survey, the course methodology was rated at 8.7 AE 0.5, organization 8.7 AE 0.4, teaching staff 9.2 AE 0.2, theoretical classes 8.7 AE 0.4, and practical sessions 8.8 AE 0.3. Conclusions: Mechanical ventilation courses are a useful educational method for health professionals in theoretical and practical mechanical ventilation.

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1999

In this paper we present a new calibration system for particle telescopes including multipulse ge... more In this paper we present a new calibration system for particle telescopes including multipulse generator and digital controller. The calibration system generates synchronized pulses of variable height for every detector channel on the telescope. The control system is based on a commercial microcontroller linked to a personal computer through an RS-232 bidirectional line. The aim of the device is to perform laboratory calibration of multi-detector telescopes prior to calibration at accelerator. This task includes evaluation of linearity and resolution of each detector channel, as well as coincidence logic. The heights of the pulses sent to the detectors are obtained by Monte Carlo simulation of telescope response to a particle #ux of any desired geometry and composition.

Local magnetic structure of heliospheric current sheet (HCS) is observed as a boundary that separ... more Local magnetic structure of heliospheric current sheet (HCS) is observed as a boundary that separate magnetic field with opposite directions. In this work, solar wind features during HCS crossings detected by ACE, WIND and, in some cases STEREO A and B, have been analyzed. Their temporal and spatial dependences are studied in terms of the HCS local orientation. It is showed important changes in some of the events probably related with transient as magnetic cloud events. Also the effect of corotating structures has been analyzed. It is presented a pool of 15 HCS crossings observed by these spacecrafts. This study analyzes the importance of the propagation of the HCS on its local structure and the connection between different observation points. Our preliminary results and future works are summarized in this work

BMC Cancer, 2014

Background: Preoperative chemoradiotherapy (CRT) is the cornerstone of treatment for locally adva... more Background: Preoperative chemoradiotherapy (CRT) is the cornerstone of treatment for locally advanced rectal cancer (LARC). Although high local control is achieved, overall rates of distant control remain suboptimal. Colorectal carcinogenesis is associated with critical alterations of the Wnt/β-catenin pathway involved in proliferation and survival. The aim of this study was to assess whether CRT induces changes in the expression of β-catenin/E-cadherin, and to determine whether these changes are associated with survival. Methods: The Immunohistochemical expression of nuclear β-catenin and membranous E-cadherin was prospectively analysed in tumour blocks from 98 stage II/III rectal cancer patients treated with preoperative CRT. Tumour samples were collected before and after CRT treatment. All patients were treated with pelvic RT (46-50 Gy in 2 Gy fractions) and 5-fluorouracil (5FU) intravenous infusion (225 mg/m 2) or capecitabine (825 mg/m 2) during RT treatment, followed by total mesorectal excision (TME). Disease-free survival (DFS) was analysed using the Kaplan-Meier method and a multivariate Cox regression model was employed for the Multivariate analysis. Results: CRT induced significant changes in the expression of nuclear β-catenin (49% of patients presented an increased expression after CRT, 17% a decreased expression and 34% no changes; p = 0.001). After a median follow-up of 25 months, patients that overexpressed nuclear β-catenin after CRT showed poor survival compared with patients that experienced a decrease in nuclear β-catenin expression (3-year DFS 92% vs. 43%, HR 0.17; 95% CI 0.03 to 0.8; p = 0.02). In the multivariate analysis for DFS, increased nuclear β-catenin expression after CRT almost reached the cutoff for significance (p = 0.06). Conclusions: In our study, preoperative CRT for LARC induced significant changes in nuclear β-catenin expression, which had a major impact on survival. Finding a way to decrease CRT resistance would significantly improve LARC patient survival.