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Aims. We present a comprehensive analysis of the performance of noise-reduction (denoising) algorithms to determine whether they provide advantages in source detection, mitigating noise on extragalactic survey images. Methods. The methods we analyze here are representative of different algorithmic families: Perona-Malik filtering, bilateral filter, total variation denoising, structure-texture image decomposition, non-local means, wavelets, and block-matching We tested the algorithms on simulated images of extragalactic fields with resolution and depth typical of the Hubble, Spitzer, and Euclid Space Telescopes, and of ground-based instruments. After choosing their best internal parameters configuration, we assessed their performance as a function of resolution, background level, and image type, in addition to testing their ability to preserve the objects fluxes and shapes. Finally, we analyze, in terms of completeness and purity, the catalogs that were extracted after applying denoising algorithms on a simulated Euclid Wide Survey VIS image and on real H160 and K-band (HAWK-I) observations of the CANDELS GOODS-South field. Results. Denoising algorithms often outperform the standard approach of filtering with the point spread function (PSF) of the image. Applying structure-texture image decomposition, Perona-Malik filtering, the total variation method by Chambolle, and bilateral filtering on the Euclid-VIS image, we obtain catalogs that are both more pure and complete by 0.2 magnitude than those based on the standard approach. The same result is achieved with the structure-texture image decomposition algorithm applied on the H160 image. The relative advantage of denoising techniques with respect to PSF filtering rises with increasing depth. Moreover, these techniques better preserve the shape of the detected objects with respect to PSF smoothing. Conclusions. Denoising algorithms provide significant improvements in the detection of faint objects and enhance the scientific return of current and future extragalactic surveys. We identify the most promising denoising algorithms among the 20 techniques considered in this study. [ABSTRACT FROM AUTHOR]

Abstract: Aim: To detect marine Bdellovibrio and like organisms (BALOs) which are able to infect Vibrio parahaemolyticus from seawater of the Adriatic, Italy. To test, prey specificity and predation efficiency of our Halobacteriovorax isolate, named HBXCO1, towards 17 Vibrio and 7 non‐Vibrio strains linked to the Adriatic sea, Italy. Methods and Results: Double layer agar plating technique was used to enumerate BALOs and to evaluate their prey specificity and predation efficiency. Transmission electron microscopy and 16S rRNA analysis were used to identify them. Means of BALOs counts ranged from 5·0 PFU per ml (March 2017) to 98·6 PFU per ml (August 2016). HBXCO1 had the ability to attack all tested prey strains of V. parahaemolyticus, Vibrio cholerae non‐O1/O139 and Vibrio vulnificus, but it did not prey on non‐Vibrio strains and V. alginolyticus under the tested conditions. Conclusions: Bdellovibrio and like organisms capable of infecting pathogenic vibrios are naturally present in seawater of the Adriatic, Italy. Isolate HBXCO1 shows prey specificity preferentially for the Vibrio genus and high predatory efficiency towards a wide range of pathogenic strains. Significance and Impact of the Study: The public impact of V. parahaemolyticus, non‐O1/O139 V. cholerae and V. vulnificus in bivalves is relevant and current decontamination processes are not always effective. We believe that the predator HBXCO1 represents a potential candidate for the development of strategies of biocontrol of pathogenic vibrios in bivalves from harvesting to trade. [ABSTRACT FROM AUTHOR]

The relationship between Vibrio parahaemolyticus strains isolated from the aquatic environment and those isolated from cases of infection in humans is poorly understood due to the low prevalence of tdh- and/or trh-positive strains in the environment. To address this concern, it would be useful to analyse the genetic relationships among environmental and food strains and with reference to clinical isolates, also applying molecular typing methods. The aim of this study was to evaluate the prevalence of toxigenic V. parahaemolyticus in Italian coastal waters and seafood, to examine intra-species variability and to identify, using serotyping and pulsed-field gel electrophoresis (PFGE), relationships among strains from different sources, geographical origin and period of isolation. Of the 192 V. parahaemolyticus strains isolated in different Italian areas and examined in this study, 25 (13.0%) proved to carry the trh gene while none of the strains proved positive to the search by PCR for tdh and Group-Specific- toxRS genes. The prevalence of toxigenic strains in the Tyrrhenian Sea was significantly lower than that calculated for the Ligurian coasts. Regarding the sources of isolation, the higher prevalence of trh-positive V. parahaemolyticus was revealed in fish, followed by clams, plankton, oysters, mussels and lastly seawater. Within the toxigenic strains, 16 serotypes and 20 distinct PFGE patterns were identified. Two clusters, which included a total of 8 V. parahaemolyticus strains, were specifically associated with the North Adriatic Sea area and were stable over time. Our results demonstrate that trh-positive V. parahaemolyticus strains circulated in Italy in the period 2002-2009 with a prevalence higher than that reported from other European and extra-European countries, confirming that toxigenic V. parahaemolyticus is an emerging public health concern in Italy, regardless of its pandemic potential. [ABSTRACT FROM AUTHOR]

Aims: The aim of this study was to investigate the presence of Vibrio vulnificus and potentially pathogenic strains of Vibrio parahaemolyticus in mullets collected from estuarine environment in Italy. Methods and Results: Two hundred and ninety-five mullets were analysed by culture using the selective medium thiosulfate citrate bile salt sucrose agar, during a monitoring period of 2 years (2008-2009). Presumptive Vibrio colonies were initially identified by using biochemical tests, and strains identified as V. parahaemolyticus and V. vulnificus were subsequently examined by PCR for the presence of species-specific and virulence genes ( toxR, trh, tdh and vvh). V. parahaemolyticus was found in 55% (162/295) of fishes and V. vulnificus in 1% (3/295) with a higher presence in summer months. The trh+/ tdh− strains were detected in 16% (47/295) of samples and only one strain resulted trh+/ tdh+. One of the V. parahaemolyticus trh+ strains isolated belonged to the O1:KUT (K untypeable), a serotype recently associated to gastroenteritis in Italy. Conclusions: This is the first report demonstrating a high percentage of potential pathogenic V. parahaemolyticus trh+ strains in estuarine fishes of the Mediterranean area. Significance and Impact of the Study: These findings indicate the potential human health risk associated with the presence of pathogenic Vibrio spp. in wild fishes. [ABSTRACT FROM AUTHOR]

Background and purpose: Frontotemporal dementia (FTD) is a degenerative disorder characterized, in its frontal variant, by psychiatric onset, deficits in executive functions and sparing of memory and visuo-spatial abilities. Studies on visuo-spatial abilities in FTD and Alzheimer’s disease (AD) have mainly focused on constructional abilities (CA) and have yielded contrasting data, often depending either on the task used or biases in the clinical selection of patients. The aim of our study was to evaluate the frequency of the CA impairment in FTD-fv and AD patients at the early stage of the disease, and to verify if some distinctive features of this impairment can characterize each pathology. Methods: The copy-drawing task (Rey Complex Figure, RCF) of 41 patients with probable mild AD and 15 patients with probable mild FTD-fv were analysed by means of quantitative and qualitative indices. Results: Data showed that both AD and FTD patients displayed similar RCF scores, as well as execution strategies, type of errors and global analysis. The FTD group only had a significant deficit in the analysis of inner details. [ABSTRACT FROM AUTHOR]

Aims: Multicentre evaluation of biochemical and molecular methods for the identification of Vibrio parahaemolyticus. Methods and Results: For the biochemical identification methods, API 20E and API 20NE and Alsina's scheme were evaluated in intra- and interlaboratory tests in order to determine the accuracy and concordance of each method. Both in intra- and interlaboratory tests, the Alsina's scheme showed the highest sensitivity (86% of correct identifications in the interlaboratory test). False-positive results were obtained by all methods (specificity was 95% for API 20E, 73% for API 20NE and 84% for Alsina's scheme) and concordance varied from 65% of API 20NE to 84% of API 20E. For the molecular identifications, polymerase chain reaction (PCR) for the detection of toxR gene, tl gene and pR72H fragment were tested on 30 strains by two laboratories. The PCR for toxR showed the highest inclusivity (96%), exclusivity (100%) and concordance (97%). Conclusions: Among the biochemical identification methods tested, the Alsina's scheme gave more reliable results; however, in order to avoid false-positive results, all the biochemical identifications should be confirmed by means of molecular methods. Significance and Impact of the Study: Availability of an efficient identification method of Vibrio parahaemolyticus to use in official control of fisheries products. [ABSTRACT FROM AUTHOR]

The existence of allometric relationships between home-range size and body mass was tested for 34 Italian mammals and 106 Italian birds. These allometries were investigated in relation to a carnivorous, omnivorous or herbivorous diet and, in the case of birds, also territoriality. Initially, non-phylogenetic comparative analyses were undertaken by fitting general linear models to data on average home-range size and average body mass obtained from the literature. Then, two phylogenetic trees for the studied species of mammals and birds were reconstructed and phylogenetic independent contrasts were applied in order to determine the influence of phylogeny on these relationships. For mammals, the type of diet proved to be a determining factor in defining the relationship between home-range size and body mass. Significant allometries were found with both conventional and phylogenetic analyses in all trophic groups. The results emphasized the importance of the spatial distribution of resources in understanding these allometries. For birds, conventional analysis showed significant relationships between home-range size and body mass, and pointed to the importance of both diet and territorial systems in understanding these allometries. After controlling for phylogeny, significant allometries were found only for those birds for which information on the size of their feeding territory was available. Regardless of the complexity of factors influencing the home-range size of a species, the outcomes of this study support the notion of the existence of an allometry between home-range size and body mass among Italian mammals and birds, suggesting that further developments of this area of investigation may prove worthwhile. [ABSTRACT FROM AUTHOR]

Aims: The aim of this research was to identify and partially purify new bacteriocin-like substances from strains of halophilic ‘non-cholera’ vibrios isolated from food sources. Methods and Results: Forty-five halophilic Vibrio spp. strains were screened for antimicrobial production. Vibrio mediterranei 1, a nonpathogenic strain, showed antimicrobial activity towards Vibrio parahaemolyticus spp. and related species. The bacteriocin-like inhibitory substance (BLIS), released by the bacteria into growth media, was concentrated by ultrafiltration and characterized. BLIS was sensitive to proteinase K, was stable in the pH range 5–9, was resistant to organic solvents and was heat stable up to 75°C. Initial purification of BLIS by size exclusion chromatography showed an apparent molecular mass of 63–65 kDa. Conclusions: This study reports the ability of V. mediterranei 1 to produce a bacteriocin-like substance inhibiting growth of V. parahaemolyticus spp. and other closely related bacteria. Significance and Impact of the Study: The strong activity of BLIS towards the human and fish pathogen V. parahaemolyticus and the persistence of antimicrobial properties under a variety of different conditions suggest its potential application in food microbiology. [ABSTRACT FROM AUTHOR]

d. ottaviani, l. masini and s. bacchiocchi. 2003. We report a biochemical method for the isolation and identification of the current species of vibrios using just one operative protocol. The method involves an enrichment phase with incubation at 30°C for 8–24 h in alkaline peptone water and an isolation phase on thiosulphate-citrate-salt sucrose agar plates incubating at 30°C for 24 h. Four biochemical tests and Alsina's scheme were performed for genus and species identification, respectively. All biochemical tests were optimized as regards conditions of temperature, time of incubation and media composition. The whole standardized protocol was always able to give a correct identification when applied to 25 reference strains of Vibrio and 134 field isolates. The data demonstrated that the assay method allows an efficient recovery, isolation and identification of current species of Vibrio in seafood obtaining results within 2–7 days. This method based on biochemical tests could be applicable even in basic microbiology laboratories, and can be used simultaneously to isolate and discriminate all clinically relevant species of Vibrio. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

Deep-sea sponge grounds are vulnerable marine ecosystems, which through their benthic-pelagic coupling of nutrients, are of functional relevance to the deep-sea realm. The impact of fishing bycatch is here evaluated for the first time at a bathyal, sponge-dominated ecosystem in the high seas managed by the Northwest Atlantic Fisheries Organization. Sponge biomass surfaces created from research survey data using both random forest modeling and a gridded surface revealed 231,140 t of sponges in the area. About 65% of that biomass was protected by current fisheries closures. However, projections of trawling tracks estimated that the sponge biomass within them would be wiped out in just 1 year by the current level of fishing activity if directed on the sponges. Because these sponges filter 56,143 ± 15,047 million litres of seawater daily, consume 63.11 ± 11.83 t of organic carbon through respiration, and affect the turnover of several nitrogen nutrients, their removal would likely affect the delicate ecological equilibrium of the deep-sea benthic ecosystem. We estimated that, on Flemish Cap, the economic value associated with seawater filtration by the sponges is nearly double the market value of the fish catch. Hence, fishery closures are essential to reach sponge conservation goals as economic drivers cannot be relied upon. [ABSTRACT FROM AUTHOR]