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The diversity and abundance of fish inhabiting complex reef habitats poses some challenges to surveys based on optical techniques, especially for schooling fish which are difficult to enumerate with such methods. Acoustic surveys are often used effectively to estimate the abundance and distribution of schooling fish but suffer from boundary effects and limited species discrimination.To reconcile these drawbacks, we present an integrated acoustic–optical survey method, to estimate the abundance of fishes in a subtropical reef habitat in Shark Bay, Western Australia, exploiting the unique benefits of each method.Acoustic backscatter attributed to multi‐species groups was partitioned to species with the help of concurrent unbaited remote underwater video. This allowed estimation of the abundance of the important fishery sparid, Chrysophrys auratus, as well as 17 other members of the diverse fish community.The study addresses some of the challenges of assessing abundance of fish species that may be aggregated, but sparsely distributed, associated with a structured habitat, and mixed within a diverse assemblage of other aggregating or solitary fishes in an area where direct capture fisheries survey gears cannot be used.Synthesis and applications. The acoustic–optical survey method provides data that are vital for the assessment of fish species in ecosystems which are difficult, or impossible for certain species, to survey with existing methods. These assessments are, in turn, essential for either ecosystem‐based fishery management or multiple single‐species quota management, which allow for the sustainable management of the associated fisheries. [ABSTRACT FROM AUTHOR]

Identification of the potential habitat of European anchovy ( Engraulis encrasicolus) at different life stages in relation to environmental conditions is an interesting subject from both ecological and management points of view. For this purpose, acoustic data from different seasons and different parts of the Mediterranean Sea along with satellite environmental and bathymetry data were modelled using generalized additive models. Similarly, egg distribution data from summer ichthyoplankton surveys were used to model potential spawning habitat. Selected models were used to produce maps presenting the probability of anchovy presence (adults, juveniles and eggs) in the entire Mediterranean basin, as a measure of habitat adequacy. Bottom depth and sea surface chlorophyll concentration were the variables found important in all models. Potential anchovy habitats were located over the continental shelf for all life stages examined. An expansion of the potential habitat from the peak spawning (early summer) to the late spawning season (early autumn) was observed. However, the most suitable areas for the presence of anchovy spawners seem to maintain the same size between seasons. Potential juvenile habitats were associated with highly productive inshore waters, being less extended and closer to coast during winter than late autumn. Potential spawning habitat in June and July based on ichthyoplankton surveys overlapped but were wider in extent compared with adult potential habitat from acoustics in the same season. Similarities and dissimilarities between the anchovy habitats as well as comparisons with sardine habitats in the oligotrophic Mediterranean Sea and other ecosystems with higher productivity are discussed. [ABSTRACT FROM AUTHOR]

Purpose This document has been prepared to support the clinical activity of cardiologists and radiologists involved in the planning and execution of magnetic resonance exams in patients implanted with pacemakers, defibrillators and loop recorders, to guarantee patients and operators safety. The author think that the issue focused in the document requires a comprehensive description of technological, scientific, regulatory and organizational aspects, related to the interaction between cardiac implantable medical devices and magnetic resonance. Methods National and international regulatory framework analysis procedural criticities review have been performed to inspire organizational models apt do manage technical issues related to magnetic resonance patients with cardiac implantable medical devices. Results Management of clinical diagnostic routine with magnetic resonance facilities could be critical for patients with implanted medical devices, due to the necessity of strictly respected complex procedures involving some different health workers (cardiologists, radiologists, medical physics experts, clinical engineer). Conclusions To perform diagnostic magnetic resonance exams on patients with cardiac implantable medical devices is really possible, but only activating organizational models and technical procedures adapted to guarantee regulatory framework respect and full traceability. [ABSTRACT FROM AUTHOR]

Purpose The Diagnostic reference level (DRL) is recognised as an important tool in identifying high and non-justified exposure levels in diagnostic imaging practice and, in general, in the optimisation practice of patient exposure. In Italy, the D.Lgs. 187/2000 has introduced a set of DRL values and has requested their use in the medical exposure practice. Since many years, it has recognised this set, derived from European guidelines published in the 90', requires an update to assure the efficacy of the tool. Methods In the last decade, with this in mind professional societies and national institutes have developed national surveys to assess level of patient exposure in different areas of diagnostic imaging. These data, together with relevant European data, have supported the development of the ISS ISTISAN 17/33 publication aiming to propose to the radiology community an updated set of national DRL values for the diagnostic and interventional radiology, i.e. general radiography, fluoroscopy and CT for adult and paediatric patients and interventional radiology for adults [1]. Results and Conclusions The ISS document can serves as a reference in the forthcoming legislative decree implementing the Council Directive 2013/59/EURATOM of 5/12/2013, laying down basic safety standards for protection against the dangers arising from exposure to ionising radiation, has been transposing at national level. Because the Directive identifies in the DRLs a useful tool to support the optimisation also in interventional radiology (IR), a practice rapidly increasing and representing a critical scenario from the point of patient radiation protection, the ISS document is introducing DRLs for the most common IR procedures. [ABSTRACT FROM AUTHOR]