1,977 research outputs found

    Settlement patterns of two spirorbidae (annelida, polychaeta) species in the harbour of Ischia (Gulf of Naples, Mediterranean Sea)

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    Studies on settlement rate of Neodexiospira pseudocorrugata and Simplaria pseudomilitaris (Polychaeta, Spirorbidae) in the Port of Ischia (Naples) are reported. Observations were carried out monthly, during a one-year cycle (April 1995-April 1996) at two different depths (0.5 and 1.5 m) using unglazed ceramic tiles as substrate. Both species reproduced throughout the year with maximum settlement in June and July at 1.5 m depth. On tiles exposed during June, 40% of individuals of N. pseudocorrugata, ranging between 0.8 and 1.6 mm coil diameter, were brooding, with broods smaller (6–14 eggs, egg diameter 75 um) than in most spirorbid species. Simplaria pseudomilitaris did not reach brooding size within any of the monthly exposure periods. In and after August, an algal bloom of attached brown filaments (Ectocarpa-ceae) covered the tiles and was accompanied by decreased settlement and heavy mortality of spirorbids. © 2000 Taylor & Francis Group, LLC

    Ecological, Social and Economic Aspects of Italian Marine Spearfishing Tournaments (2009-2020)

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    Marine recreational spearfishing is practiced by a small proportion of recreational fishers and ecological, social and economic aspects of such activities are poorly understood with respect to recreational angling. The Italian Federation of Sport Fishing and Underwater Activities (FIPSAS) started in 2009 the collection of catch data related to Italian spearfishing tournaments. Here, we provide the first snapshot of this catch data regarding 48 tournaments organized in 29 different Italian localities from 2009 to 2020. We also developed a survey to collect social and economic information that has been administrated to participants to the tournaments. We retrieved 8843 specimens caught by spearfishers, which accounted for 33 species and a total biomass of 5665 kg (mean individual mass ± standard error; 0.64 ± 0.01 kg). The five most frequently species represented 78% of the specimens caught (white seabream, Diplodus sargus 48%; brown wrasse, Labrus merula 12%; brown meagre, Sciaena umbra 9%, green wrasse, Labrus viridis 5%; salema, Sarpa salpa 4%). The overall catch per unit effort for all the tournaments was 0.47 ± 0.01 kg/spearfisher/h, and we showed interesting effects of type of tournaments and type of displacement on it. We also assessed the accuracy of participants to catch fish in accordance to tournaments-specific minimum weight limits. The five most caught species showed that spearfishers committed errors around 50 g below the weight limit. The survey showed that spearfishers participating to tournaments are trophy-fish oriented (i.e., they would rather catch one or two big fish than ten smaller fish), but not particularly catch oriented (i.e., they are just as happy if they do not shoot the fish they see and a fishing trip can be successful even if no fish are caught). Regarding the motives for fishing, they fish for experiencing adventure, excitement and new and different things as well as to be underwater. Participants spent from 2 to 26 days in the tournament locations (median equal to 7 days), which implies a total expenditure to solely participate to the tournaments ranging from 800 to 3500 Euros (mean ± standard deviation; 1800 ± 591 euros). This study represents the first ecological, social and economic baseline knowledge for an integrative management of contemporary spearfishing tournament

    Nanoplastics in the oceans: Theory, experimental evidence and real world

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    This review critically analyses >200 papers collected by searching on Pubmed the word \u201cnanoplastics\u201d, a group of emerging contaminants which are receiving growing attention. The present review intends to provide an overview of current knowledge on nanoplastic pollution starting with the theory of polymer degradation, passing to laboratory confirmation of nanoplastic formation and ending with the possible occurrence in sea water samples. Most of the observations proposed focus the attention on polystyrene (PS) because the majority of research knowledge is based on this polymer. Moreover, we thoroughly describe what effects have been observed on different organisms tested in controlled conditions. Nanoplastics formation, fate and toxicity seem to be a very dynamic phenomenon. In light of this, we identify some aspects retained crucial when an ecotoxicological study with nanoplastics is performed and which elements of nanoplastics toxicity could be deeper covered

    Eastern Illinois State College - Fifty Years of Public Service

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    This book is a narrative of the Eastern Illinois State College at Charleston, Illinois. I t does not attempt to interpret Eastern\u27s role in our national educational development. The writer has not used the story of Eastern as a means for expounding educational doctrine, and he hopes that his own pedagogical theories have not intruded themselves in these pages. The book has been written for the former \u27students and teachers of Eastern and for the present and future sons and daughters of the school. Those who come to Eastern in the years ahead may find in these pages some hint of the forces and personalities which have made the school and some understanding of the school\u27s traditions. Eastern is a good school and here, at least in part, is why.https://thekeep.eiu.edu/eiu_history/1001/thumbnail.jp

    Preliminary evaluation of the climate-induced fatigue in wood: A physical and computational approach

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    Wood is the organic hygroscopic material for excellence. Due to its extremely easy handling, it has always been used in many applications, especially as building material for artefacts and works of art. However, it is highly climate-susceptible as it swells or shrinks by exchanging moisture with the surrounding environment when natural or artificial microclimatic fluctuations occur. The shrinkage/swelling of wood, if repeated over time, may cause the arising of deformations or damage that may lead to catastrophic failures. For this reason, in this work, a preliminary study about the effect that repeated microclimatic loads have on wooden samples is carried out. To do so, well-established fatigue approaches have been implemented, with few simplifying considerations. The case study is a slice of Scots pine which is assumed to be stored inside Ringebu stave church (Norway). Ringebu indoor microclimate is reconstructed, through a proper transfer function, starting from outdoor temperature data downloaded from web platforms. The reconstructed indoor temperature timeseries cover three periods: far past (1948–1977), recent past (1981–2010) and far future (2071–2100). The results obtained for the three periods made it possible to gain insights about the climate-induced fatigue of wood and to preliminary assess the impact of climate change. It has been observed that successive similar temperature fluctuations can be potentially treated as a block of constant amplitude and constant frequency fatigue-like load. Finally, introducing few simplifying considerations, it has been assessed that the simulated behavior is coherent with the theoretical one coming from exploiting well-established thermo-based methods

    Migration controls in Italy and Hungary From conditionalized to domesticized humanitarianism at the EU borders

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    This article analyses the migration control narrative in Italy and Hungary at the nexus of humanitarianism and securitisation. We concentrate on how the humanitarian discourse is undervalued as the EU border states emphasise either full securitisation or else securitisation as a condition for humanitarianism when it comes to border management and refugee protection measures. We trace, first, how politicians conceptualise humanitarianism for the self and for the extension of the self; and, second, how they conditionalize humanitarianism for the other. Reflecting on the institutional and discursive nexus of humanitarianism and securitization in effect to migration controls, our aim is also to contextualise political narratives of Europe and how politicians use them to affect the public. We elaborate on this nexus considering how it foregrounds human rights for the self but challenges humanitarianism as it undervalues human rights for the other. In order to see how migration politics is framed for everyday consumption, we are referring to tropes emerging in major political speeches in Italy and Hungary, and develop two conceptual terms suggesting conditionalised humanitarianism and domesticised humanitarianism

    Does Warming Enhance the Effects of Eutrophication in the Seagrass Posidonia oceanica?

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    Seagrass meadows are disappearing at rates comparable to those reported for mangroves, coral reefs, and tropical rainforests. One of the main causes of their decline is the so-called cultural eutrophication, i.e., the input of abnormal amounts of nutrients derived from human activities. Besides the impact of eutrophication at a local scale, the occurrence of additional stress factors such as global sea warming may create synergisms in detriment of seagrass meadows’ health. In the present study, we aimed to evaluate if plants undergoing chronic cultural eutrophication and plants growing in relatively pristine waters are more (or less) sensitive to heat stress, nutrient load and the combination of both stressors. To address this question, a mesocosm experiment was conducted using Posidonia oceanica collected from two environments with different nutrients load history. Plants were exposed in controlled conditions to high nutrient concentrations, increased temperature and their combination for 5 weeks, to assess the effect of the single stressors and their interaction. Our results revealed that plants experiencing chronic cultural eutrophication (EU) are more sensitive to further exposure to multiple stressors than plants growing in oligotrophic habitats (OL). OL and EU plants showed different morphological traits and physiological performances, which corroborates the role of local pressures in activating different strategies in response to global environmental changes. EU-plants appeared to be weaker during the treatments, showing the greatest percentage of mortality, particularly under increased temperature. Temperature and nutrient treatments showed opposite effects when tested individually and an offset response when combined. The activation of physiological strategies with high energetic expenses to cope with excess of nutrients and other stressors, could affect plants present and future persistence, particularly under eutrophic conditions. Our results represent a step forward in understanding the complex interactions that occur in natural environments. Moreover, unraveling intraspecific strategies and the role of local acclimation/adaptation in response to multiple stressors could be crucial for seagrass conservation strategies under a climate change scenario
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