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1.
EJNMMI Phys ; 11(1): 73, 2024 Aug 23.
Article in English | MEDLINE | ID: mdl-39174856

ABSTRACT

OBJECTIVE: Positron Emission Tomography (PET) is a well-known imaging technology for the diagnosis, treatment, and monitoring of several diseases. Most PET scanners use a Ring-Shaped Detector Configuration (RSDC), which helps obtain homogeneous image quality but are restricted to an invariable Field-of-View (FOV), scarce spatial resolution, and low sensitivity. Alternatively, few PET systems use Open Detector Configurations (ODC) to permit an accessible FOV adaptable to different target sizes, thus optimizing sensitivity. Yet, to compensate the lack of angular coverage in ODC-PET, developing a detector with high-timing performance is mandatory to enable Time-of-Flight (TOF) techniques during reconstruction. The main goal of this work is to provide a proof of concept PET scanner appropriate for constructing the new generation of ODC-PET suitable for biopsy guidance and clinical intervention during acquisition. The designed detector has to be compact and robust, and its requirements in terms of performance are spatial and time resolutions < 2 mm and < 200 ps, respectively. METHODS: The present work includes a simulation study of an ODC-PET based on 2-panels with variable distance. The image quality (IQ) and Derenzo phantoms have been simulated and evaluated. The phantom simulations have also been performed using a ring-shaped PET for comparison purposes of the ODC approach with conventional systems. Then, an experimental evaluation of a prototype detector that has been designed following the simulation results is presented. This study focused on tuning the ASIC parameters and evaluating the scintillator surface treatment (ESR and TiO2), and configuration that yields the best Coincidence Time Resolution (CTR). Moreover, the scalability of the prototype to a module of 64 × 64mm2 and its preliminary evaluation regarding pixel identification are provided. RESULTS: The simulation results reported sensitivity (%) values at the center of the FOV of 1.96, 1.63, and 1.18 for panel distances of 200, 250, and 300 mm, respectively. The IQ reconstructed image reported good uniformity (87%) and optimal CRC values, and the Derenzo phantom reconstruction suggests a system resolution of 1.6-2 mm. The experimental results demonstrate that using TiO2 coating yielded better detector performance than ESR. Acquired data was filtered by applying an energy window of ± 30% at the photopeak level. After filtering, best CTR of 230 ± 2 ps was achieved for an 8 × 8 LYSO pixel block with 2 × 2 × 12mm3 each. The detector performance remained constant after scaling-up the prototype to a module of 64 × 64mm2, and the flood map demonstrates the module's capabilities to distinguish the small pixels; thus, a spatial resolution < 2 mm (pixel size) is achieved. CONCLUSIONS: The simulated results of this biplanar scanner show high performance in terms of image quality and sensitivity. These results are comparable to state-of-the-art PET technology and, demonstrate that including TOF information minimizes the image artifacts due to the lack of angular projections. The experimental results concluded that using TiO2 coating provide the best performance. The results suggest that this scanner may be suitable for organ study, breast, prostate, or cardiac applications, with good uniformity and CRC.

2.
Nat Commun ; 15(1): 4299, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38769086

ABSTRACT

Spins of electrons in silicon MOS quantum dots combine exquisite quantum properties and scalable fabrication. In the age of quantum technology, however, the metrics that crowned Si/SiO2 as the microelectronics standard need to be reassessed with respect to their impact upon qubit performance. We chart spin qubit variability due to the unavoidable atomic-scale roughness of the Si/SiO2 interface, compiling experiments across 12 devices, and develop theoretical tools to analyse these results. Atomistic tight binding and path integral Monte Carlo methods are adapted to describe fluctuations in devices with millions of atoms by directly analysing their wavefunctions and electron paths instead of their energy spectra. We correlate the effect of roughness with the variability in qubit position, deformation, valley splitting, valley phase, spin-orbit coupling and exchange coupling. These variabilities are found to be bounded, and they lie within the tolerances for scalable architectures for quantum computing as long as robust control methods are incorporated.

3.
Nature ; 627(8005): 772-777, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38538941

ABSTRACT

The encoding of qubits in semiconductor spin carriers has been recognized as a promising approach to a commercial quantum computer that can be lithographically produced and integrated at scale1-10. However, the operation of the large number of qubits required for advantageous quantum applications11-13 will produce a thermal load exceeding the available cooling power of cryostats at millikelvin temperatures. As the scale-up accelerates, it becomes imperative to establish fault-tolerant operation above 1 K, at which the cooling power is orders of magnitude higher14-18. Here we tune up and operate spin qubits in silicon above 1 K, with fidelities in the range required for fault-tolerant operations at these temperatures19-21. We design an algorithmic initialization protocol to prepare a pure two-qubit state even when the thermal energy is substantially above the qubit energies and incorporate radiofrequency readout to achieve fidelities up to 99.34% for both readout and initialization. We also demonstrate single-qubit Clifford gate fidelities up to 99.85% and a two-qubit gate fidelity of 98.92%. These advances overcome the fundamental limitation that the thermal energy must be well below the qubit energies for the high-fidelity operation to be possible, surmounting a main obstacle in the pathway to scalable and fault-tolerant quantum computation.

4.
Lancet Glob. Health ; 11(6): 933-941, jun. 2023. tab, ilus, mapa, graf
Article in English | RSDM | ID: biblio-1532085

ABSTRACT

From the start of the SARS-CoV-2 outbreak, global sequencing efforts have generated an unprecedented amount of genomic data. Nonetheless, unequal sampling between high-income and low-income countries hinders the implementation of genomic surveillance systems at the global and local level. Filling the knowledge gaps of genomic information and understanding pandemic dynamics in low-income countries is essential for public health decision making and to prepare for future pandemics. In this context, we aimed to discover the timing and origin of SARS-CoV-2 variant introductions in Mozambique, taking advantage of pandemic-scale phylogenies. Methods: We did a retrospective, observational study in southern Mozambique. Patients from Manhiça presenting with respiratory symptoms were recruited, and those enrolled in clinical trials were excluded. Data were included from three sources: (1) a prospective hospital-based surveillance study (MozCOVID), recruiting patients living in Manhiça, attending the Manhiça district hospital, and fulfilling the criteria of suspected COVID-19 case according to WHO; (2) symptomatic and asymptomatic individuals with SARS-CoV-2 infection recruited by the National Surveillance system; and (3) sequences from SARS-CoV-2-infected Mozambican cases deposited on the Global Initiative on Sharing Avian Influenza Data database. Positive samples amenable for sequencing were analysed. We used Ultrafast Sample placement on Existing tRees to understand the dynamics of beta and delta waves, using available genomic data. This tool can reconstruct a phylogeny with millions of sequences by efficient sample placement in a tree. We reconstructed a phylogeny (~7·6 million sequences) adding new and publicly available beta and delta sequences. Findings: A total of 5793 patients were recruited between Nov 1, 2020, and Aug 31, 2021. During this time, 133 328 COVID-19 cases were reported in Mozambique. 280 good quality new SARS-CoV-2 sequences were obtained after the inclusion criteria were applied and an additional 652 beta (B.1.351) and delta (B.1.617.2) public sequences were included from Mozambique. We evaluated 373 beta and 559 delta sequences. We identified 187 beta introductions (including 295 sequences), divided in 42 transmission groups and 145 unique introductions, mostly from South Africa, between August, 2020 and July, 2021. For delta, we identified 220 introductions (including 494 sequences), with 49 transmission groups and 171 unique introductions, mostly from the UK, India, and South Africa, between April and November, 2021. Interpretation: The timing and origin of introductions suggests that movement restrictions effectively avoided introductions from non-African countries, but not from surrounding countries. Our results raise questions about the imbalance between the consequences of restrictions and health benefits. This new understanding of pandemic dynamics in Mozambique can be used to inform public health interventions to control the spread of new variants. Funding: European and Developing Countries Clinical Trials, European Research Council, Bill & Melinda Gates Foundation, and Agència de Gestió d'Ajuts Universitaris i de Recerca.


Subject(s)
Humans , Male , Female , SARS-CoV-2/genetics , COVID-19/prevention & control , Mozambique/epidemiology , Phylogeny , Prospective Studies , Retrospective Studies , Pandemics/prevention & control , COVID-19/epidemiology
5.
ENFURO: Rev. Asoc. Esp. A.T.S. Urol ; (131): 32-36, oct. 2016. ilus, graf
Article in Spanish | IBECS | ID: ibc-157638

ABSTRACT

Desde hace más de una década, la Unidad de Nutrición del Hospital General Universitario Gregorio Marañón inició una línea de trabajo encaminada a la detección precoz de pacientes desnutridos. En el año 2003 participó en el estudio multicéntrico europeo EuroOOPS, sobre prevalencia de pacientes con riesgo nutricional al ingreso hospitalario. El estudio PREDyCES, realizado a nivel nacional en el año 2009, aportó resultados muy relevantes, justificando la necesidad de hacer un cribado nutricional. En el año 2013, la Unidad de Nutrición implantó un sistema de gestión de calidad (SGC) según la norma UNE-EN ISO 9001:2008, poniendo en marcha el cribado nutricional. Desde el año 2014 hasta la actualidad, se ha conseguido implantar el cribado nutricional trabajando conjuntamente profesionales de la Unidad de Nutrición, enfermeras de hospitalización y Subdirección de Sistemas de Información, utilizando un programa informático incluido dentro de la prescripción de dieta oral (Dietools) que ya se utilizaba en las unidades de hospitalización


From more than a decade ago the Nutrition Unit of the Hospital General Universitario Gregorio Marañón launched a line of work aimed at the early detection of malnourished patients. In the year 2003 participated in the european multicenter study EuroOOPS, on the prevalence of patients with nutritional risk at admission to the hospital. The PREDyCES study conducted at the national level in the year 2009 provided very relevant results, justifying the need to make a nutritional screening. In the year 2013 the Nutrition Unit introduced a quality management system (QMS) according to the standard UNE-EN ISO 9001:2008 by launching nutritional screening. From the year 2014 until the present it has been able to implement nutritional screening working together professionals from the Nutrition Unit, nurses of hospitalization and subaddress of information systems using a computer program included within the prescription of oral diet (Dietools) that was already used in the units of hospitalization


Subject(s)
Humans , Nutrition Assessment , Nutritional Status , Malnutrition/epidemiology , Mass Screening/methods , Hospitalization/statistics & numerical data , Risk Factors
6.
Rev. esp. cardiol. (Ed. impr.) ; 66(10): 797-802, oct. 2013.
Article in Spanish | IBECS | ID: ibc-115595

ABSTRACT

Introducción y objetivos. Los receptores de trasplante cardiaco que sobreviven más de 20 años están aumentando. Poco se conoce de su seguimiento, sus comorbilidades y su mortalidad. Identificar predictores de larga supervivencia puede guiar la selección de candidatos para los donantes disponibles. Métodos. Se revisó la información sobre la clase funcional, las comorbilidades y la mortalidad de pacientes trasplantados antes de 1992. Para identificar los predictores de supervivencia > 20 años, se construyó un modelo de regresión logística utilizando las variables asociadas a supervivencia en el análisis univariable. Resultados. Se comparó a 39 supervivientes con seguimiento > 20 años (el 26% del total) con 90 pacientes que sobrevivieron entre 1 y 20 años. Las principales complicaciones fueron hipertensión, disfunción renal, infecciones y neoplasias. Tras 30 meses de seguimiento, 6 murieron, lo que implica una mortalidad del 6%/año (frente a un 2,5-3% en los años 1 a 19). Las principales causas de muerte fueron infección (50%), cáncer (33%) y vasculopatía del injerto (17%). Los supervivientes eran más jóvenes y delgados, y tenían cardiopatía no isquémica y menos isquemia en cirugía. La regresión logística identificó la edad del receptor < 45 años (odds ratio = 3,9; intervalo de confianza del 95%, 1,6-9,7; p = 0,002) y la miocardiopatía idiopática (odds ratio = 3; intervalo de confianza del 95%, 1,4-7,8; p = 0,012) como predictores independientes de supervivencia > 20 años. Conclusiones. En nuestra serie, más del 25% sobrevive más de 20 años con el mismo injerto y lleva vida independiente a pesar de las comorbilidades. La edad del receptor < 45 años y la miocardiopatía idiopática se asociaron a larga supervivencia. Estos datos pueden ayudar a la asignación de donantes (AU)


Introduction and objectives. The number of heart-transplant recipients exceeding 20 years of follow-up is steadily increasing. However, little is known about their functional status, comorbidities, and mortality. Identifying the predictors of prolonged survival could guide the selection of candidates for the low number of available donors. Methods. Functional status, morbidities, and mortality of heart-transplant patients between 1984 and 1992 were analyzed. To identify predictors of 20-year survival, a logistic regression model was constructed using the covariates associated with survival in the univariate analysis. Results. A total of 39 patients who survived 20 years (26% of patients transplanted before 1992) were compared to 90 recipients from the same period who died between 1 and 20 years post-transplantation. Major complications were hypertension, renal dysfunction, infections, and cancer. After a mean follow-up of 30 months, 6 survivors had died, yielding a mortality rate of 6% per year (vs 2.5%-3% in years 1-19). Causes of mortality were infection (50%), malignancy (33%), and allograft vasculopathy (17%). Long-term survivors were younger and leaner, and had nonischemic cardiomyopathy and lower ischemic time. Logistic regression identified recipient age <45 years (odds ratio=3.9; 95% confidence interval, 1.6-9.7; P=.002) and idiopathic cardiomyopathy (odds ratio=3; 95% confidence interval, 1.4-7.8; P=.012) as independent predictors for 20-year survival. Conclusions. One fourth of all heart-transplant patients in our series survived >20 years with the same graft, and most enjoy independent lives despite significant comorbidities. Recipient age <45 years and idiopathic cardiomyopathy were associated with survival beyond 2 decades. These data may help decide donor allocation (AU)


Subject(s)
Adult , Middle Aged , Humans , Heart Transplantation/methods , Heart Transplantation , Quality of Life , Graft Survival/physiology , Cardiomyopathy, Hypertrophic/complications , Immunosuppression Therapy/instrumentation , Immunosuppression Therapy/methods , Risk Factors , Heart Transplantation/rehabilitation , Heart Transplantation/trends , Comorbidity , Odds Ratio , Survival Rate , Confidence Intervals , Body Mass Index , Multivariate Analysis
7.
Arch. bronconeumol. (Ed. impr.) ; 49(7): 282-288, jul. 2013. tab, graf, ilus
Article in Spanish | IBECS | ID: ibc-114168

ABSTRACT

OBJETIVO: Analizar la distribución de la producción, la repercusión y la colaboración mundial en tabaquismo en el área del aparato respiratorio a través del Science Citation Index-Expanded (SCI-E) en el periodo 2001-2010 y su inclusión en el primer cuartil del Journal Citation Report (JCR). MÉTODOS: La búsqueda bibliográfica fue realizada en el SCI-E. La estrategia de búsqueda empleada fue «smok*» OR «tobac*», delimitándose la investigación al periodo 2001-2010, documentos «articles» para el área del aparato respiratorio. RESULTADOS: A nivel mundial, en el área del aparato respiratorio y para el periodo analizado se encontraron un total de 1.858 artículos (ignorando la colaboración) sobre tabaquismo. La media del número de artículos publicados por quinquenio fue superior para el periodo 2006-2010 que para el 2001-2005; sin embargo, el número de citas recibidas fue superior para los documentos publicados en el primer quinquenio comparado con el segundo y, como consecuencia, el índice de citación también resultó superior en el primer quinquenio con respecto al segundo. El 40,47% de los artículos (752 documentos; ignorando la colaboración) estaban publicados en revistas del primer cuartil. Hemos encontrado una red de colaboración entre países bien establecida y cohesionada. CONCLUSIONES: La producción en tabaquismo en el área de respiratorio aumentó a lo largo del periodo analizado, hallándose el 40% de dicha producción en las revistas situadas en el primer cuartil del JCR. Encontramos una alta citación, siendo la Unión Europea de los 27 la que presenta una mayor repercusión e impacto. La red de colaboración se encuentra activa, bien consolidada y cohesionada (AU)


AIM: To analyze the distribution of the production, repercussion and co-authorship of articles on smoking in the "respiratory system" category through the Science Citation Index Expanded (SCI-E) and their inclusion in the first quartile of the Journal Citation Report (JCR). METHODS: The literature search was performed in the SCI-E. Articles were selected for 2001-2010 for "respiratory system" using the descriptors "smok*" and "tobac*". RESULTS: We found 1858 articles (ignoring collaboration) on the topic of smoking. The median number of published articles by five-year period was higher for the 2006-2010 period vs the 2001-2005 period; in contrast, the number of citations and the citation index was higher for documents published in the first five-year period. Some 40.47% (ignoring collaboration) of the articles (752 documents, ignoring collaboration) were published in first quartile journals. We found very well established and cohesive co-authorship networks. CONCLUSIONS: Articles on smoking in the area of respiratory medicine increased in this time period, with 40% of the total documents in journals in the first quartile of the JCR. The citation rate was high, with the EU-27 countries having higher impact and repercussion. We found very well established and cohesive co-authorship networks (AU)


Subject(s)
Humans , Male , Female , Smoking/epidemiology , Smoking/prevention & control , Smoking Prevention , Tobacco Use Disorder/complications , Bibliometrics , Smoking/mortality , Smoking/physiopathology , Respiratory System/physiopathology , Social Support
8.
Arch. bronconeumol. (Ed. impr.) ; 47(1): 25-34, ene. 2011. tab, ilus
Article in Spanish | IBECS | ID: ibc-88170

ABSTRACT

ObjetivoEl objetivo ha sido comparar entre dos quinquenios (1998 a 2002 con 2003 a 2007) la producción, repercusión y la colaboración de artículos sobre tabaquismo de autores españoles a través del Science Citation Index (SCI).MétodoLa búsqueda se realizó en el SCI Expanded. Fueron seleccionados todos los tipos de documentos y la búsqueda se restringió al “título”; palabras clave: “smok*” y “tobac*”.ResultadosFueron un total de 588 artículos, de los que 399 (67,85%) fueron originales, 54 (9,18%) cartas al director y 35 (5,95%) editoriales. La producción ha crecido, pasando de 234 (39,8%) documentos (98/02) a 354 (60,2%) en 03/07. Al comparar la media anual del total de artículos por quinquenios 98/02 vs 03/07 (47±8 vs 71±16 [p=0,024]) la diferencia es significativa, igual que si comparamos las medias anuales por quinquenios de los originales (34±6 vs 46±9 [p=0,041]). La media de citas/trabajo por quinquenios fue de 14,1±2,1 para 98/02 y del 5,6±2,5 para 03/07 (p=0,003). El índice de colaboración anual aumentó, pasando la media de 6,77 firmas/trabajo en 98/02, a 6,87 firmas/trabajo en 03/07. Ha aumentado el número de redes de colaboración de instituciones y autores.ConclusionesTanto la producción científica como la colaboración entre autores e instituciones han aumentado en el periodo estudiado. Son los artículos más antiguos los que más citas tienen(AU)


ObjectiveThe aim of this study was to compare the production, impact and co-authorship of publications by Spanish authors on smoking and tobacco between two time periods (1998/2002 vs 2003/2007) using Science Citation Index (SCI).MethodsThe literature search was performed in the SCI-Expanded on 20 November 2008. All types of documents by Spanish authors were selected. The search was restricted to the title, and the key words used were “smok*” and “tobac*”. The statistical analysis was descriptive (95% CI).ResultsA total of 588 documents were obtained, with 399 (67.85%) original papers, 54 (9.18%) letters to the editor, and 35 (5.95%) editorials. Productivity increased between the 98/02 to 03/07 periods: 234 (39.8%) documents versus 354 (60.2%). We have found significant differences between the two periods (98/02 vs 03/07) in total mean annual documents (47±8 vs 71±16 [p=0.024]) and total mean annual original papers (34±6 vs 46±9 [p=0.041]). The mean number of citations per document was 14.1±2.1 for 98/02 period and 5.6±2.5 for 03/07 period (p=0.003). The co-authorship annual index had increased; with a mean of 6.77 signatures/document for 98/02 period to a mean of 6.87 for 03/07 period. Authors and institution networks collaborations had increased between the two periods.ConclusionsSpanish production and co-authorship of documents on smoking and tobacco have increased between these two periods. The earlier period documents received more citations(AU)


Subject(s)
Humans , Impact Factor , Smoking , Tobacco Use Cessation , 50088 , Databases, Bibliographic
9.
Gac. sanit. (Barc., Ed. impr.) ; 23(3): 222e34-222e43, mayo-jun. 2009. ilus, tab
Article in Spanish | IBECS | ID: ibc-110744

ABSTRACT

Objetivo: El objetivo de este trabajo fue establecer los patrones de colaboración científica internacional y la visibilidad que genera la coautoría de artículos sobre tabaquismo en relación a países, a través del Science Citation Index-Expanded (SCI-Expanded) en el periodo de 1999 a 2003. Material y métodos: Se seleccionaron los artículos de colaboración sobre tabaquismo entre países en SCI-Expanded (1999-2003). Se analizaron las redes de colaboración subyacente entre países, comparando su productividad (número de artículos producidos), su visibilidad (número de citas recibidas) y centralidad (grado nodal, intermediación y proximidad). Resultados: Se recuperaron 3.484 artículos en los que habían participado 5.008 instituciones de 79 países. Reino Unido fue el más productivo, seguido de Alemania y Francia. Reino Unido fue, asimismo, el país que publicó más artículos (570) de colaboración interinstitucional, seguido de Estados Unidos y Alemania. Sin embargo, Estados Unidos fue el que publicó más artículos en colaboración internacional, seguido de Reino Unido y Francia. Todos los países recibieron más citas por sus artículos de colaboración interinstitucional o internacional que por los publicados sin ningún tipo de colaboración. Las redes de colaboración se encuentran completamente conectadas en un único componente, y el aumento que experimenta anualmente el tamaño de estas redes entre países se realiza a expensas de países nuevos en la periferia de la red. Conclusión: Existe una correlación positiva entre la colaboración internacional e interinstitucional y el número de citas que recibe un artículo. La citación de artículos se mantiene constante a lo largo del periodo analizado (AU)


Objective: The aim of this study was to analyze patterns of scientific collaboration and the visibility generated by coauthorship of articles on smoking among different countries on a world-wide basis through the Science Citation Index-Expanded (SCI-expanded) from 1999 to 2003. Material and methods: We selected articles on smoking resulting from collaboration among different countries in the SCI-Expanded (1999-2003). The underlying networks of collaboration among countries were analyzed by comparing production (number of articles published), visibility (number of citations received) and centrality (node degree, intermediation and proximity). Results: A total of 3,484 articles were obtained, in which 5,008 institutions from 79 countries participated. The most productive country was the United Kingdom, with Germany and France in the second and third places. The United Kingdom also published the largest number of articles with inter-institutional collaboration (570 articles), with the USA and Germany in second and third places. The USA published the largest number of articles with international collaboration with the United Kingdom and France in the second and third places. All countries received a greater number of citations for articles resulting from international and inter-institutional collaboration than for those performed without collaboration. Networks of collaboration were completely connected through a single component and the annual increase in size of these inter-country networks was due to new countries joining the periphery of the network. Conclusions: We found a positive correlation between international and inter-institutional collaboration and the number of citations received by articles on smoking research. The number of citations per year remained constant throughout the 5-year study period (AU)


Subject(s)
Humans , Smoking/therapy , Smoking Cessation/methods , 50088 , Cooperative Behavior , Authorship in Scientific Publications , Science and Technology Information Networks , Scientific and Technical Publications
10.
Arch. bronconeumol. (Ed. impr.) ; 43(7): 378-385, jul.2007. ilus, tab
Article in Es | IBECS | ID: ibc-055266

ABSTRACT

Objetivo: Analizar la red de colaboración científica que genera la coautoría de artículos científicos entre centros sanitarios españoles en el área de tabaquismo. Material y métodos: Se seleccionaron los artículos sobre tabaquismo aparecidos en Science Citation Index entre los años 1999 a 2003, en cuya autoría participaron 2 o más centros sanitarios españoles. Se analizó la red de colaboración subyacente, comparando las medidas más importantes de centralidad y elaborando mapas bibliométricos que permiten su visualización. Se emplearon las herramientas informáticas para el análisis de redes UCINET® y NETDRAW®. Resultados: Treinta y cinco centros sanitarios españoles (29 hospitales y 6 centros de salud), pertenecientes a 8 comunidades autónomas distintas, intervinieron en 21 trabajos de colaboración nacional interinstitucional entre centros sanitarios. El Hospital de La Princesa obtiene los valores más altos de grado nodal (16), grado de proximidad normalizado (86,66) y grado de intermediación (39), y forma parte del núcleo de la red, junto con los Hospitales de Cruces, San Pedro de Alcántara, La Paz, Vall d'Hebron y General Yagüe. Las comunidades autónomas de Castilla y León, Madrid y Cataluña son asignadas al núcleo de la red de colaboración intercomunitaria basada en la coautoría de trabajos científicos entre centros sanitarios. Conclusiones: El análisis de redes permite identificar las instituciones más influyentes en la red de colaboración científica que genera la coautoría de artículos científicos en el área de tabaquismo. El Hospital de la Princesa destaca en todas las medidas de centralidad. Las comunidades autónomas de Castilla y León, Madrid y Cataluña configuran un subgrupo de la red altamente interconectado y cohesionado


Objective: To analyze the network structure of collaboration between medical centers sharing authorship of scientific articles on smoking. Material and methods: Articles reporting smoking research by authors from 2 or more Spanish medical centers between 1999 and the end of 2003 were identified through the Science Citation Index. The network of collaboration behind the research was analyzed and the most important measures of centrality were compared. To display the data, scientometric maps were constructed using UCINET and NETDRAW network analysis tools. Results: Thirty-five Spanish medical centers (29 hospitals and 6 health care clinics) in 8 autonomous communities were involved in 21 collaborative research projects. Hospital de La Princesa was the network core institution with the highest degrees of nodal (16), closeness (88.66), and betweenness (39) centrality. Other core nodes in the network were the following hospitals: de Cruces, San Pedro de Alcántara, La Paz, Vall d'Hebron, and General Yagüe. The autonomous communities of Castile and Leon, Madrid, and Catalonia were assigned positions at the core of the intercommunity collaborative network based on coauthorship of scientific papers shared among their medical centers. Conclusions: Network analysis helps identify the most influential institutions in a scientific community that generates coauthored articles in the field of smoking research. Hospital de la Princesa had the highest measures of centrality. The autonomous communities of Castile and Leon, Madrid, and Catalonia form a highly connected, cohesive subgroup within the network


Subject(s)
Humans , Technical Cooperation , Tobacco Use Disorder/therapy , Tobacco Use Cessation/methods , Periodicals as Topic/statistics & numerical data , Biomedical Research/statistics & numerical data , Multicenter Studies as Topic/statistics & numerical data
11.
Arch. bronconeumol. (Ed. impr.) ; 43(4): 212-218, abr. 2007. tab
Article in Es | IBECS | ID: ibc-052299

ABSTRACT

Objetivo: Analizar a través del Science Citation Index la producción científica española en tabaquismo entre 1999 y 2003, situando a nuestro país en el contexto mundial y de la Unión Europea. Material y métodos: Se ha realizado un estudio bibliométrico mediante la búsqueda en el campo "título" del Science Citation Index Expanded. El análisis estadístico fue descriptivo (intervalo de confianza del 95%). Resultados: Se recopilaron 292 documentos sobre tabaquismo publicados por autores españoles. Las subáreas más productivas fueron las siguientes: salud pública, educación y economía de la salud con 57 documentos, seguidas de las subáreas de respiratorio, investigación experimental y medicina interna con 36 artículos cada una. Medicina Clínica, con 35 artículos (12%), y Archivos de Bronconeumología, con 20 (6,8%), fueron las revistas con un mayor número de documentos. La colaboración internacional se realizó con instituciones de la Unión Europea y EE UU, y la media ± desviación estándar de citaciones recibidas fue de 5,12 ± 8,6 (intervalo: 59-0). España aporta a la producción mundial en tabaquismo el 8,34%, y a la de la Unión Europea el 12,85%. Conclusiones: La investigación en tabaquismo en España se desarrolla adecuadamente, con una alta repercusión, aunque la aportación es discreta. La colaboración internacional, el hecho de que el artículo esté escrito en inglés y que el primer firmante sea extranjero son las variables que aumentan el número de citas


Objective: To analyze Spanish scientific productivity from 1999 through 2003 in the area of smoking research, in comparison with world and European Union research, based on data in the Science Citation (SCI) Index. Material and methods: This bibliometric study was carried out by searching the title field of the Science Citation Index Expanded. Descriptive statistics with 95% confidence intervals (CI) were compiled. Results: Two-hundred ninety-two documents on smoking by Spanish authors were located. The most productive subspecialties were the group comprised of public health, education and health economics with 57 articles, and areas of the respiratory system, experimental research, and internal medicine with 36 articles each. The journals that published the largest number of articles located were Medicina Clínica, with 35 articles (12%) and Archivos de Bronconeumología with 20 (6.8%). International collaboration was undertaken with institutions in the United States of America and other European Union countries. The mean (SD) number of citations received was 5.12 (8.6) (range 59-0). Spain contributed 8.34% of the SCI-indexed smoking research overall and 12.85% of SCI-indexed smoking research from the European Union. Conclusions: Smoking research is developing appropriately in Spain and has high impact, even though output is modest. Factors associated with increased citation are international collaboration, language (being written in English), and having a non-Spanish first author


Subject(s)
Humans , Tobacco Use Disorder , Biomedical Research/statistics & numerical data , Bibliometrics , Databases, Bibliographic/statistics & numerical data , Periodicals as Topic/statistics & numerical data
13.
Rev. argent. radiol ; 67(3): 249-253, 2003. ilus, tab
Article in Spanish | LILACS | ID: lil-383809

ABSTRACT

El síndrome SAPHO, acrónimo de Sinovitis, Acné, Pústulas, Hiperostosis y Osteítis, es una entidad nosológica que engloba múltiples afecciones que tienen un común compromiso osteoarticular y cutáneo. Se presenta una enferma de 59 años de edad que consulta por intenso dolor esternal y luego de un año padece exantema pustular palmo-plantar, acné y fiebre. Se le realiza una Tomografía computada, gamagrafía ósea y biopsia de las lesiones cutáneas, con lo cual se llega al diagnóstico de síndrome SAPHO. Se efectúa una reseña histórica de las distintas publicaciones sobre patologías encuadradas en el síndrome y se realiza una revisión bibliográfica de las teorías sobre su posible etiología, la cual continúa en discusión, aunque la tendencia actual es considerarla una artropatía seronegativa de similar fisiopatología al síndrome de Reiter


Subject(s)
Humans , Female , Middle Aged , Acquired Hyperostosis Syndrome/diagnosis , Acquired Hyperostosis Syndrome/diagnosis , Prognosis , Acquired Hyperostosis Syndrome/etiology , Acquired Hyperostosis Syndrome/drug therapy , Acquired Hyperostosis Syndrome/etiology , Acquired Hyperostosis Syndrome/drug therapy , Tomography, X-Ray Computed
14.
Rev. argent. radiol ; 67(3): 249-253, 2003. ilus, tab
Article in Spanish | BINACIS | ID: bin-4170

ABSTRACT

El síndrome SAPHO, acrónimo de Sinovitis, Acné, Pústulas, Hiperostosis y Osteítis, es una entidad nosológica que engloba múltiples afecciones que tienen un común compromiso osteoarticular y cutáneo. Se presenta una enferma de 59 años de edad que consulta por intenso dolor esternal y luego de un año padece exantema pustular palmo-plantar, acné y fiebre. Se le realiza una Tomografía computada, gamagrafía ósea y biopsia de las lesiones cutáneas, con lo cual se llega al diagnóstico de síndrome SAPHO. Se efectúa una reseña histórica de las distintas publicaciones sobre patologías encuadradas en el síndrome y se realiza una revisión bibliográfica de las teorías sobre su posible etiología, la cual continúa en discusión, aunque la tendencia actual es considerarla una artropatía seronegativa de similar fisiopatología al síndrome de Reiter (AU)


Subject(s)
Humans , Female , Middle Aged , Acquired Hyperostosis Syndrome/diagnosis , Acquired Hyperostosis Syndrome/diagnosis , Acquired Hyperostosis Syndrome/etiology , Acquired Hyperostosis Syndrome/drug therapy , Prognosis , Tomography, X-Ray Computed , Acquired Hyperostosis Syndrome/etiology , Acquired Hyperostosis Syndrome/drug therapy
15.
Rev. argent. radiol ; 65(2): 147-150, 2001. ilus
Article in Spanish | LILACS | ID: lil-305828

ABSTRACT

La localización broncopulmonar del Sarcoma de Kaposi (SK) es frecuente en pacientes con SIDA, que padecen afección cutánea. Se presenta el cuadro clínico e imagenología de un enfermo de 38 años de edad y se efectúa una revisión de las cuatro formas clínicas del SK. Además, se analiza la dificultad del diagnóstico pre-mortem cuando existe compromiso broncopulmonar, señalando al estudio endoscópico sin biopsia como prueba suficiente para confirmar la afección, cuando el endoscopista experimentado comprueba las lesiones típicas


Subject(s)
Humans , Male , Adult , Sarcoma, Kaposi , Bronchi , Bronchoscopy , Foscarnet , Herpesvirus 8, Human , Prognosis , Lung/pathology , Sarcoma, Kaposi , Tomography, X-Ray Computed , Trachea/pathology
16.
Rev. argent. radiol ; 65(2): 147-150, 2001. ilus
Article in Spanish | BINACIS | ID: bin-8616

ABSTRACT

La localización broncopulmonar del Sarcoma de Kaposi (SK) es frecuente en pacientes con SIDA, que padecen afección cutánea. Se presenta el cuadro clínico e imagenología de un enfermo de 38 años de edad y se efectúa una revisión de las cuatro formas clínicas del SK. Además, se analiza la dificultad del diagnóstico pre-mortem cuando existe compromiso broncopulmonar, señalando al estudio endoscópico sin biopsia como prueba suficiente para confirmar la afección, cuando el endoscopista experimentado comprueba las lesiones típicas (AU)


Subject(s)
Humans , Male , Adult , Sarcoma, Kaposi/diagnosis , Sarcoma, Kaposi/classification , Sarcoma, Kaposi/complications , Trachea/pathology , Bronchi/pathology , Lung/pathology , Herpesvirus 8, Human , Foscarnet/therapeutic use , Tomography, X-Ray Computed , Bronchoscopy , Prognosis
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