725 research outputs found

    Show me your body and I tell you how hold you are: a non-invasive methodto define 6 life history-classes in Risso's dolphins (Grampus griseus), using an identified trial population in the Atlantic

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    European Cetacean Society Conference Workshop, Galway, Ireland, 25th March 2012."[…]. The objective of this paper is to present a new non-intrusive and inexpensive method to classify six life history stages in Risso's dolphins: from newborn calf to old-adult. We propose an age-class indicator model using the scarification patterns and the species unique discoloration process. We developed two methods and tested these among 52 rankers to examine if our proposed methods could be applied by anybody and if they would conform with our age class model. We also investigated the possible differences in the scarification patterns between genders. We used a longterm followed identified population of Risso's dolphins in the Azores to set up our test methods and report our present results.

    Habitat differentiation between groups of Risso's dolphins as evidence of coastal nursery areas

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    26th Annual Conference of the European Cetacean Society, Galway, Ireland 26-28 March 2012.Previous studies have shown strong site fidelity by Risso's dolphins at a site off Pico Island, Azores. Females with calves tend to be seen together, often with newborn calves. In this study we analyse position and photo-identification data gathered on ocean surveys from 2004 to 2007 to look at the distribution of females with calves of different ages (newborns to 6 months old, 6 months to 2 years and 2 to 4 years) and compare it with pods with no calves present. The association of the different groups with selected ecogeographical variables was tested, and a maximum entropy model was used to create habitat suitability maps, using a 50mx50m grid. The female pods with younger calves were found to have a significantly distinct distribution from those with older calves or without calves. The main difference was that the pods with younger calves tended to be found closer to the shore, whereas the other groups used a wider offshore area. More extensive sampling is required in order to validate the existence and geographical distribution of coastal nursery areas for this species. However, we believe the present data is enough to elicit precautionary conservation measures to reduce human impact on a vulnerable part of the dolphin society, such as that associated with boat traffic, whale watching and swimming with dolphins operations

    Developments in the “Northern and Southern Hake” Case Study of FishPi

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    The overarching objective of the FishPi project is to strengthen regional cooperation in the area of fisheries data collection. The role of every case study within the project is to bring together the countries with the most involvement in the fisheries selected to coordinate and cooperate in the search of a probabilistic regional sampling design. To this aim, case study 4 (CS4) is focused in the Northern and Southern Hake stocks. The work done in the case study include the description of the fishery at a regional level, the compilation of the present national sampling activity, the compilation of the logbooks and/or sales notes from 2013 and 2014 –to have a single regional data set of all trips of interest in the region– and different runs of simulations to test the selected sampling scenarios and stratifications. Finally, an objective evaluation of the performance of these regional designs is expected to understand the changes needed compared to the present situation. This document presents the progress done in this case study, from the data compilation to the simulations, documenting the different steps taken and allowing an understanding of the pending tasks

    Dermal denticles and morphometrics of the sailfin roughshark Oxynotus paradoxus (Elasmobranchii, Oxynotidae), with comments on its geographic distribution

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    The dermal denticles of the sailfin roughshark Oxynotus paradoxus are described and illustrated with SEM pictures, based on two specimens captured at the Azores. The flank denticles are similar to those of O. centrina, with a central cusp flanked by two smaller lateral cusps, rising from the lateral ridges, and a secondary median cusp posterior to the main one. Differences in squamation between both species are described. Body proportions of the Azorean specimens are given and found to be consistent with those reported by previous authors. The published information shows depth of capture to have a mode at 570 m. A bathybenthic habitat has been suggested, with spring reproductive migrations to the continental shelf. The presence of this species in the Azores and Mid-Atlantic Ridge represents a significant westward extension of its previously known geographic distribution, the continental shelf and upper slope of the north and eastern Atlantic. It is possible that O. paradoxus is continuously distributed along the north-eastern Atlantic floor, deeper than presently known. Alternatively, separate slope and ridge populations may exist

    Behavioural responses of Risso’s dolphin, Grampus griseus, to remote biopsy sampling

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    25th Conference of the European Cetacean Society. Long-terms datasets on marine mammals: learning from the past to manage the future, Cadiz, Spain, 21-23 March 2011.Biopsy sampling from free-ranging cetaceans is a widespread method used in various biological studies. Since this is an intrusive research technique, it’s important to determine its impact. We examined the short-term behavioural reactions of Risso’s dolphins, Grampus griseus (2.6-4m in length), off Pico Island, to remote biopsy sampling. Biopsies were conducted over a consecutive two year period using a crossbow with Finn Larsen bolts and tips. Sampling followed a number of precautionary rules, including taking samples only in calm seas, when animals were travelling; no more than 1-4 shots per group; and females with nursing calves were not exposed to sampling. Behavioural responses were analysed by visual observation using two scales of behavioural reactions: i) the reaction of the targeted individual, and ii) the reaction of the focal group to which the targeted individual belonged. We defined five categories of intensity of behavioural response (none, low, medium, high, very high) and five types of display response (quick dive, QD; diving & leaving, D&L; jumping, J; tail slapping, TS; and speeding away at surface, SS). A total of 189 shots were made (115 hits, 74 miss) during 61 survey days. Tissue was obtained in 83% of the hits. No significant differences were found between hits and misses in behavioural responses or types of display (Kruskal Wallis test). In 9% of the cases there was no visible reaction, while most (48%) behavioural responses were of low intensity. The frequencies of the display responses differed significantly from each other (chi-squared test). The types QD and D&L constituted 79% of the responses. Group reaction was observed during 1/5 of the shots, (main behaviour D&L-51%). Although biopsy sampling is an invasive method, our results indicate that if basic precaution rules are followed low intensity behavioural responses can be expected for half of the time

    Evaluation of policy based admission control mechanisms in NGN

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    The 3GPP consortium proposed in the release 7 of the IP Multimedia Subsystem (IMS) a Diameter interface for the resource admission communication process replacing the previous COPS solution. Although both academic and industry communities have deeply debate the advantages and disadvantages of each protocol, its impact in NGN may have not been thoroughly quantified. This paper compares both protocols in terms of messages exchanged between network entities, and of bandwidth requirements during the admission control process. Based on general network operator environment characteristics, we present several exploitation scenarios where it is analyzed the scalability and adequacy of each protocol

    On-Line Determination of Biomass in a Microalga Bioreactor Using a novel Computerized Flow Injection Analysis System

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    A flow injection analysis (FIA) device has been developed, which is able to assay successfully for biomass in a microalga bioreactor. The device is fully computerized and is operated via diluting small aliquots of the culture followed by measuring optical density (OD); this figure is then accurately correlated with biomass, in terms of both cell number and ash-free dry weight, during the entire culture time. Furthermore, the device is not expensive, is highly versatile, and is easy to operate owing to specifically developed, user-friendly software. The growth rate and biomass productivity of Pavlova lutheri, cultivated under batch and semicontinuous modes, were monitored as experimental testing model

    Supporting the design of an ambient assisted living system using virtual reality prototypes

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    APEX, a framework for prototyping ubiquitous environments, is used to design an Ambient Assisted Living (AAL) system to enhance a care home for older people. The environment allows participants in the design process to experience the proposed design and enables developers to explore the design by rapidly developing alternatives. APEX provided the means to explore alternative designs through a virtual environment. It provides a mediating representation (a boundary object) allowing users to be involved in the design process. A group of residents in a city-based care home were involved in the design. The paper describes the design process and lessons learnt for the design of AAL systems.EPSRC - Engineering and Physical Sciences Research Council(EP/G059063/1)Jose C. Campos acknowledges support by the FCT – Fundação para a Ciência e a Tecnologia (Portuguese Foundation for Science and Technology) within project UID/EEA/50014/2013. José Luís Silva acknowledges support from project PEST-OE/EEI/LA0009/2015. Michael Harrison was also funded by EPSRC research grant EP/G059063/1: CHI+MED (Computer–Human Interaction for Medical Devices)

    Creating new functional biomaterials: construction and production of Bone Morphogenetic 2-ELP hybrid proteins

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    Bone morphogenetic protein 2 (BMP-2) is a potent osteoinductive cytokine from the TGF-β superfamily that triggers the development of stem cells into osteoblasts. Its therapeutic interest has led to the development of various production systems for recombinant variables of BMP-2. Production has been achieved in expression systems ranging from animal cells to bacteria, but is always associated with three major drawbacks: low production rates (in animal cells), low activity (bacterial cells) and low solubility due to aggregation in inclusion bodies (bacterial cells) [1]. In this study we have developed a strategy to overcome the low production levels as well as the insolubility of BMP-2 in E. coli by fusing it with an elastin like polymer (ELP). This recombinant ELP, based on repetitions of the main monomer VPAVG, displays no measurable cytotoxicity [2] and exhibits thermoresponsive properties as well as hysteresis behaviour [3]. By exploring this thermal responsiveness we are able to purify the fusion protein using a simple and low cost method and thus avoid expensive chromatographic techniques. The mature human-BMP2 domain was cloned in frame to the N-terminus of the (VPAVG)n (n = 60 or 220) polymers. The production of the genetic constructs was achieved in E. coli BL21 (DE3) with Lysogeny Broth (LB) supplemented with lactose for auto-induction. Purification of the hybrid BMP2:(VPAVG)n polymers was accomplished by exploring the thermal responsiveness of the ELP tail. Physical and chemical characterization as well as bioactivity studies of both constructs are currently in progress. 1. Bessa P. C., Casal M., Reis R. L. (2008) “Bone morphogenetic proteins in tissue engineering: the road from laboratory to the clinic, part I (Basic concepts)”, Journal of tissue engineering and regenerative medicine 2, 1-13; 2. Bessa, P., Machado, R., Nürnberger , S., Dopler, D., Banerjee, A., Cunha, A. M., Rodríguez-Cabello, C., Redl, H., van Griensven, M., Reis, R.L., Casal, M. 2010. Thermoresponsive self-assembled elastin-based nanoparticles for delivery of BMPs. Journal of Controlled Release 142: 312–318. 3. Machado R., Ribeiro A., Padrão J., Silva D., Nobre A., Teixeira J., Arias F., Cunha A., Rodroguez-Cabello J., Casal M. (2009) “Exploiting the natural ocurring elastin: construction, production and characterization of a recombinant thermoplastic protein-based polymer”, Journal of Nano Research, 6, 133-145

    Nuevos registros de monogeneos (Platyhelminthes: Monogenea) infectando algunos peces marinos del litoral peruano

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    A parasitological survey searching monogeneans infesting marine fish was carried out during June 2018 and January 2020 from the coastal zone of Puerto Pizarro, Tumbes (northern Peru) and from the coastal zone of Chorrillos, Lima (central Peru). The gills, skin, nasal cavities, or branchial gill-cover of seven species were sampled. Ten monogenean species assigned to six families and nine genera were identified. The monogeneans Callorhynchocotyle callorhynchi (Manter, 1955); Capsala biparasiticum (Goto, 1894) Price, 1938; Euryhaliotrema sagmatum Kritsky & Boeger, 2002; Listrocephalos kearni Bullard, Payne &Braswell, 2004; Magniexcipula lamothei Bravo-Hollis, 1981; Nasicola klawei (Stunkard, 1962) Yamaguti, 1968; and Pseudorhabdosynochus anulus Violante-Gonzalez & Rojas-Herrera, 2011 are registered for the first time in Peru. While Capsala gregalis (Wagner & Carter, 1967) Chisholm & Whittington, 2007; Heterocotyle margaritae Chero, Cruces, Sáez, Santos & Luque, 2020; and Monocotyle luquei Chero, Cruces, Iannacone, Sanchez, Minaya, Sáez & Alvariño, 2016 have been previously registered in Peruvian waters, however, the region of Tumbes (northern Peru) represent a new locality record for these species.Durante junio de 2018 y enero de 2020 se realizó un levamiento parasitológico para buscar monogeneos que infectan peces marinos en la zona costera de Puerto Pizarro, departamento de Tumbes (norte de Perú) y en la zona costera de Chorrillos, departamento de Lima (centro de Perú). Se analizaron las branquias, la piel, las cavidades nasales o el opérculo de siete especies. Se identificaron diez especies de monogeneos, asignadas a seis familias y nueve géneros. Los monogeneos Callorhynchocotyle callorhynchi (Manter, 1955); Capsala biparasitica (Goto, 1894) Price, 1938; Euryhaliotrema sagmatum Kritsky y Boeger, 2002; Listrocephalos kearni Bullard, Payne y Braswell, 2004; Magniexcipula lamothei Bravo-Hollis, 1981; Nasicola klawei (Stunkard, 1962) Yamaguti, 1968; y Pseudorhabdosynochus anulus Violante-Gonzalez & Rojas-Herrera, 2011 son registrados por primera vez en Perú. Mientras que, Capsala gregalis (Wagner y Carter, 1967) Chisholm y Whittington, 2007; Heterocotyle margaritae Chero, Cruces, Sáez, Santos & Luque, 2020; y Monocotyle luquei Chero, Cruces, Iannacone, Sanchez, Minaya, Sáez & Alvariño, 2016 han sido previamente registrados en aguas peruanas, sin embargo, la región de Tumbes (norte de Perú) representa un nuevo registro de localidad para estas especies
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