134 research outputs found
Fotosensibilizadores de Ir(III) para terapia y bioimagen
En los últimos años la terapia fotodinámica (TFD) se está utilizando para el tratamiento de algunos cánceres como puede ser el de piel o garganta entre otros. Esta terapia presenta unas características de selectividad y control espacial que permite minimizar muchos efectos secundarios, por lo que es altamente demandada. Los compuestos de Ir(III) han demostrado tener grandes capacidades como fotosensibilizadores (FSs) en TFD. Por ello, en este trabajo se ha llevado a cabo el desarrollo de nuevos compuestos de Ir(III) luminiscentes con el objetivo de desarrollar fotosensibilizadores que permitan optimizar su uso en esta técnica. Un correcto diseño de la esfera de coordinación del Ir(III) hace que se puedan obtener complejos donde la activación del compuesto sea usando bajas energías, aumentando así la posibilidad de llegar al tratamiento de tumores más grandes. Además, se han incorporado unos ligandos N^N conteniendo uncromóforo (antraceno o acridina), de modo que permitan utilizar técnicas de bioimagen como la microcopia de fluorescencia utilizando irradiaciones diferentes a las usadas para la activación del FSs, y permitiendo así hacer la activación de cada uno de losfragmentos por separado. Una vez caracterizados mediante espectrometría de masas y espectroscopia de RMN, también se han estudiado sus propiedades ópticas y se han realizado ensayos preliminares de su capacidad citotóxica y fotocitotóxica en la línea tumorales de pulmón (A549) así como su potencial como agente de bioimagen.<br /
Estimating front-wave velocity of infectious diseases: a simple, efficient method applied to bluetongue
Understanding the spatial dynamics of an infectious disease is critical when attempting to predict where and how fast the disease will spread. We illustrate an approach using a trend-surface analysis (TSA) model combined with a spatial error simultaneous autoregressive model (SARerr model) to estimate the speed of diffusion of bluetongue (BT), an infectious disease of ruminants caused by bluetongue virus (BTV) and transmitted by Culicoides. In a first step to gain further insight into the spatial transmission characteristics of BTV serotype 8, we used 2007-2008 clinical case reports in France and TSA modelling to identify the major directions and speed of disease diffusion. We accounted for spatial autocorrelation by combining TSA with a SARerr model, which led to a trend SARerr model. Overall, BT spread from north-eastern to south-western France. The average trend SARerr-estimated velocity across the country was 5.6 km/day. However, velocities differed between areas and time periods, varying between 2.1 and 9.3 km/day. For more than 83% of the contaminated municipalities, the trend SARerr-estimated velocity was less than 7 km/day. Our study was a first step in describing the diffusion process for BT in France. To our knowledge, it is the first to show that BT spread in France was primarily local and consistent with the active flight of Culicoides and local movements of farm animals. Models such as the trend SARerr models are powerful tools to provide information on direction and speed of disease diffusion when the only data available are date and location of cases
Recommended from our members
The prediction of swarming in honeybee colonies using vibrational spectra
In this work, we disclose a non-invasive method for the monitoring and predicting of the swarming process within honeybee colonies, using vibro-acoustic information. Two machine learning algorithms are presented for the prediction of swarming, based on vibration data recorded using accelerometers placed in the heart of honeybee hives. Both algorithms successfully discriminate between colonies intending and not intending to swarm with a high degree of accuracy, over 90% for each method, with successful swarming prediction up to 30 days prior to the event. We show that instantaneous vibrational spectra predict the swarming within the swarming season only, and that this limitation can be lifted provided that the history of the evolution of the spectra is accounted for. We also disclose queen toots and quacks, showing statistics of the occurrence of queen pipes over the entire swarming season. From this we were able to determine that (1) tooting always precedes quacking, (2) under natural conditions there is a 4 to 7 day period without queen tooting following the exit of the primary swarm, and (3) human intervention, such as queen clipping and the opening of a hive, causes strong interferences with important mechanisms for the prevention of simultaneous rival queen emergence
Evaluating methods to quantify spatial variation in the velocity of biological invasions
La formación plástica y la enseñanza de la E.G.A. en: "Gradute Shcool of Architecture". Universidad Columbia. New York "College of Architecture". Universidad de Houston. "School of Architecture". Universidad de Illinois
Junta de Andalucía-Consejería de Política TerritorialEscuela Técnica Superior de Arquitectura de la Universidad de SevillaExcmo. Ayuntamiento de SevillaColegio Oficial de Arquitectos de Andalucía Occidenta
Border Disease Virus among Chamois, Spain
Approximately 3,000 Pyrenean chamois (Rupicapra pyrenaica pyrenaica) died in northeastern Spain during 2005–2007. Border disease virus infection was identified by reverse transcription–PCR and sequencing analysis. These results implicate this virus as the primary cause of death, similar to findings in the previous epizootic in 2001
Using geographically weighted regression to explore the spatially heterogeneous spread of bovine tuberculosis in England and Wales
An understanding of the factors that affect the spread of endemic bovine tuberculosis (bTB) is critical for the development of measures to stop and reverse this spread. Analyses of spatial data need to account for the inherent spatial heterogeneity within the data, or else spatial autocorrelation can lead to an overestimate of the significance of variables. This study used three methods of analysis—least-squares linear regression with a spatial autocorrelation term, geographically weighted regression (GWR) and boosted regression tree (BRT) analysis—to identify the factors that influence the spread of endemic bTB at a local level in England and Wales. The linear regression and GWR methods demonstrated the importance of accounting for spatial differences in risk factors for bTB, and showed some consistency in the identification of certain factors related to flooding, disease history and the presence of multiple genotypes of bTB. This is the first attempt to explore the factors associated with the spread of endemic bTB in England and Wales using GWR. This technique improves on least-squares linear regression approaches by identifying regional differences in the factors associated with bTB spread. However, interpretation of these complex regional differences is difficult and the approach does not lend itself to predictive models which are likely to be of more value to policy makers. Methods such as BRT may be more suited to such a task. Here we have demonstrated that GWR and BRT can produce comparable outputs
Honeybee Colony Vibrational Measurements to Highlight the Brood Cycle
Insect pollination is of great importance to crop production worldwide and honey bees are amongst its chief facilitators. Because of the decline of managed colonies, the use of sensor technology is growing in popularity and it is of interest to develop new methods which can more accurately and less invasively assess honey bee colony status. Our approach is to use accelerometers to measure vibrations in order to provide information on colony activity and development. The accelerometers provide amplitude and frequency information which is recorded every three minutes and analysed for night time only. Vibrational data were validated by comparison to visual inspection data, particularly the brood development. We show a strong correlation between vibrational amplitude data and the brood cycle in the vicinity of the sensor. We have further explored the minimum data that is required, when frequency information is also included, to accurately predict the current point in the brood cycle. Such a technique should enable beekeepers to reduce the frequency with which visual inspections are required, reducing the stress this places on the colony and saving the beekeeper time
- …