An operative gamma camera for sentinel lymph node procedure in case of breast cancer

Large field of view gamma cameras are widely used to perform lymphoscintigraphy in the sentinel lymph nodes (SLN) procedure in case of breast cancer. However, they are not specified for this application and their sizes do not enable their use in the operative room to control the excision of the all SLN. We present the results obtained with a prototype of a new mini gamma camera developed especially for the operative lymphoscintigraphy of the axillary area in case of breast cancer. This prototype is composed of 10 mm thick parallel lead collimator, a 2 mm thick GSO:Ce inorganic scintillating crystal from Hitachi and a Hamamatsu H8500 flat panel multianode (64 channels) photomultiplier tube (MAPMT) equipped with a dedicated electronics. Its actual field of view is 50 × 50mm2. The gamma interaction position in the GSO scintillating plate is obtained by calculating the center of gravity of the fired MAPMT channels. The measurements performed with this prototype demonstrate the usefulness of this mini gamma camera for the pre, per and post-operative identification of SLN's and how its complementary role with an intraoperative handheld gamma probe enables to improve the efficiency of this practice. A 100 × 100mm2 field of view camera designated to cover the entire axillary area is under investigation

Doñana wetlands

The Doñana wetlands in SW Spain constitute what remains of the original 180,000 ha of marshland in the Guadalquivir delta. The natural wetlands are protected in the National Park and World Heritage Site (54,252 ha), and include more than 3,000 temporary dune ponds fed mainly from groundwater and 30,000 ha of seasonal marshes dependent on surface flows. They are particularly famous for their avifauna, and hold more wintering waterfowl than any other European wetland. Wading birds exploit surrounding ricefields and fishfarms, and their breeding numbers are increasing. Doñana holds a high diversity of herpetofauna, mammals, invertebrates and plants, with several endemic species. The wetlands have high value for ecotourism and are the setting for the El Rocío pilgrimage. Alien fish and crayfish have had a significant impact. The quantity and quality of water entering the wetlands is under threat from groundwater extraction and other effects of agricultural and urban development.Peer reviewe

Existence of radial stationary solutions for a system in combustion theory

In this paper, we construct radially symmetric solutions of a nonlinear noncooperative elliptic system derived from a model for flame balls with radiation losses. This model is based on a one step kinetic reaction and our system is obtained by approximating the standard Arrehnius law by an ignition nonlinearity, and by simplifying the term that models radiation. We prove the existence of 2 solutions using degree theory

Mixtures of Tails in Clustered Automobile Collision Claims

Knowledge of the tail shape of claim distributions provides important actuarial information. This paper discusses how two techniques commonly used in assessing the most appropriate underlying distribution can be usefully combined. The maximum likelihood approach is theoretically appealing since it is preferable to many other estimators in the sense of best asymptotic normality. Likelihood based tests are, however, not always capable of discriminating among non-nested classes of distributions. Extremal value theory offers an attractive tool to overcome this problem. A much larger set of distribution classes is nested by their tail parameter. This paper shows that both estimation strategies can be usefully combined when the data generating process is characterized by strong clustering in time and size. We find that the extreme value theory is a useful starting point in detecting the appropriate distribution class. Once that has been achieved, the likelihood-based EM-algorithm is proposed to capture the clustering phenomena. Clustering is particularly pervasive in actuarial data. An empirical application to a four-year data set of Dutch automobile collision claims is therefore used to illustrate the approach

State of the art of studies investigating the relationship between emotion regulation and gambling disorder: preliminary results from a systematic review study

Background: Despite the fact that the role played by Emotion Regulation (ER) in Gam-bling Disorder (GD) has been for long neglected in the gambling research field, a growing number of recent studies investigated this topic. Still, the role of ER in GD remains under-mined and ignored in most treatment protocols or guidelines. This may be partially due to the lack of systematic examination of empirical results providing solid and definitive indications that can be translated in clinical practice. The aim of the present study is thus to conduct a systematic review on such topic.Methods: Following the PRISMA statements, a systematic search was conducted.Results: We identified twenty-eight studies that explored ER features and strategies in gambling. Despite most of the study supported the hypothesis of a relationship between GD and general ER deficits, results are not consistent with regard to the nature of the features characterizing ER profiles of DGs. Also, results appear to differ as a function of the sample used across studies. Finally, despite promising preliminary evidences, some features of ER appeared to be under-examined in empirical literature (e.g. rumination processes).Discussion: Clinical implications, methodological issues and future lines of research are discussed

Flame balls for a free boundary combustion model with radiative transfer

We study radial flame ball solutions of a three-dimensional free boundary problem (FBP), which models combustion of a gaseous mixture with dust in a microgravity environment. The model combines diffusion of mass and temperature with reaction at the flame front, the reaction rate being temperature dependent. The radiative flux due to the presence of dust enters the equation for the temperature in the form of a divergence term. This flux is modeled by Eddington's radiative transfer equation. The main parameters are the dimensionless opacity and the ratio of radiative and thermal fluxes. We prove existence of spherical flame ball solutions for the FBP. Bifurcation diagrams are obtained, exhibiting the multiplicity of solutions. Singular limit cases of the parameter values are also discussed. © 2006 Society for Industrial and Applied Mathematics

Weak relationship between risk assessment studies and recorded mortality in wind farms

Wind farms generate little or no pollution. However, one of their main adverse impacts is bird mortality through collisions with turbine rotors. Environmental impact assessment (EIA) studies have been based on observations of birds before the construction of wind farms. We analysed data from 53 EIAs in relation to the actual recorded bird mortalities at 20 fully installed wind farms to determine whether this method is accurate in predicting the risk of new wind farm installations. Bird data from EIAs were compared with bird collisions per turbine and year at functional post-constructed wind farms to identify any relationship between pre- and post-construction studies. Significant differences in birds recorded flying among the 53 proposed wind farms were found by the EIAs. Similar results were obtained when only griffon vultures Gyps fulvus and other raptors were considered. There were significant differences in indexes, including the relative index of breeding birds close to proposed locations, among the 53 proposed wind farm sites. The collision rate of birds with turbines was one of the highest ever recorded for raptors, and the griffon vulture was the most frequently killed species. Bird mortality varied among the 20 constructed wind farms. No relationship between variables predicting risk from EIAs and actual recorded mortality was found. A weak relationship was found between griffon vulture and kestrel Falco sp. mortality and the numbers of these two species crossing the area. Synthesis and applications. There was no clear relationship between predicted risk and the actual recorded bird mortality at wind farms. Risk assessment studies incorrectly assumed a linear relationship between frequency of observed birds and fatalities. Nevertheless, it is known that bird mortality in wind farms is related to physical characteristics around individual wind turbines. However, EIAs are usually conducted at the scale of the entire wind farm. The correlation between predicted mortality and actual mortality must be improved in future risk assessment studies by changing the scale of these studies to focus on the locations of proposed individual wind turbine sites and working on a species specific level. © 2011 The Authors. Journal of Applied Ecology © 2011 British Ecological Society.Peer Reviewe

Bayesian Arbitrage Threshold Analysis

A Bayesian estimation procedure is developed for estimating multiple regime (multiple threshold) vector autoregressive models appropriate for deviations from financial arbitrage relationships. This approach has clear advantages over classical stepwise threshold autoregressive analysis. Whereas classical procedures first have to identify thresholds and then perform piecewise autoregressions, we simultaneously estimate threshold and autoregression parameters. To illustrate the Bayesian procedure, we estimate a no-arbitrage band within which index futures arbitrage is not profitable despite (persistent) deviations from parity