2,030 research outputs found

    The Recent non-marine ostracods of Tunisia: an updated checklist with remarks on their regional distribution patterns and ecological preferences

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    Different lines of investigation have recently contributed to increasing the available knowledge about the invertebrates inhabiting inland waters of north Africa, but a comprehensive synopsis on Tunisian Ostracoda is missing to date. An updated checklist of Recent non-marine ostracods from Tunisia and data on their distribution is thus offered here, representing the most extensive survey on this crustacean group ever carried out in inland waters throughout the country. One-hundred-five sites covering various climate zones, from Mediterranean to desert areas, were sampled between 2002 and 2012. Most of the considered water bodies were temporary or ephemeral habitats, but a few permanent sites were sampled as well. Overall, 18 genera and 32 taxa of putative species rank were collected in the frame of this survey, among which nine species and five genera were new to Tunisian fauna. As a result of this study and based on previous investigations, nine families (Candonidae, Cyprididae, Cytherideidae, Darwinulidae, Ilyocyprididae, Leptocytheridae, Limnocytheridae, Loxoconchidae, Paradoxostomatidae), 29 genera and at least 45 species of non-marine ostracods are currently known for Tunisia, which thus prove to host the most diverse ostracod fauna among north African countries. The number of species occurring in a single sample varied from 1 to 4. The Eucypris virens complex was the most widespread taxon (58 records), followed by Heterocypris barbara (30 records), Heterocypris incongruens (22 records), and Sarscypridopsis aculeata (16 records). For some ostracod species, clear distributional gradients associated with different climatic conditions were observed. The affinities with adjacent Maghrebian ostracod faunas are discussed. This study confirms the crucial role played by marginal aquatic habitats for the conservation of biodiversity, in particular in arid and semi-arid regions

    An updated checklist of Recent ostracods (Crustacea: Ostracoda) from inland waters of Sicily and adjacent small islands with notes on their distribution and ecology

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    Because of its position in the middle of the Mediterranea Sea and a complex geological history that has promoted repeated waves of biological colonization, Sicily (Southern Italy) is of particular interest from a biogeographical perspective. A number of previous investigations, dating back as far as the end of the 19th century, have contributed to gather information about the occurrence of Recent non-marine ostracods in Sicily, making this region one of the most intensively studied areas of the Central Mediterranean. Published data on ostracod distributions have been integrated through an extensive field survey on mainland Sicily and surrounding small islands and archipelagos. Altogether, 271 ostracod samples and 11 sediment samples from dry water bodies were analysed from 218 sites visited between 2002 and 2017. Sampling sites were selected to encompass all the most common types of freshwater aquatic habitats, both natural and artificial, present in the area. Thirty-nine ostracods were identified at species level and 12 at supraspecific level. The present study reports four species (Cypria subsalsa, Eucypris mareotica, Physocypria kerkyrensis, Vestalenula boteai) and one genus (Vestalenula) as new for both peninsular Italy and adjacent islands, and three species (Candonopsis novaezelandiae, Ilyocypris inermis, Neglecandona neglecta) and two genera (Candonopsis and Physocypria) as new for Sicily. The updated checklist of the study area now includes at least 46 nominal species and other taxa identified at supraspecific level, belonging to 28 genera in 8 families (Candonidae, Cyprididae, Cytherideidae, Darwinulidae, Hemicytheridae, Ilyocyprididae, Limnocytheridae and Notodromadidae). The present investigation represents a significant addition to the knowledge of the ostracod diversity and distribution in the Sicilian area and in Italy as a whole. It also provides a sound baseline data for further comparative faunal studies aimed at investigating the affinities and origins of the central Mediterranean inland-water ostracod faunas, and to analyse their biogeographic patterns

    The crustacean fauna of Bayan Onjuul area (TĂ´v Province, Mongolia) (Crustacea: Branchiopoda, Copepoda, Ostracoda)

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    Due to the wide extension of the country and to the shortness of the ice-free season, the inlandwater crustacean fauna of Mongolia is, to date, incompletely known. However, based on the available literature, Mongolian inland waters appear to be characterised by a high biodiversity, including some taxa still waiting to be described. Novel data on the branchiopod, copepod, and ostracod crustaceans from central Mongolian steppe, from the “Tuul” and “Umard goviin guveet-Khalhiin” hydrographical basins, are presented herein. While large branchiopods, some anomopod families, and copepods are well-represented in the collected samples, ostracods are rare, and the anomopod family Chydoridae is apparently absent in the sampled water bodies. The anomopod Macrothrix dadayi and the cyclopoid Microcyclops afghanicus are here reported for the first time for the Mongolian fauna. Furthermore, two branchiopods (i.e. Moina sp. and Artemia sp.), three copepods (i.e. Diacyclops sp., Arctodiaptomus cf. alpinus, and Arctodiaptomus cf. wierzejskii), and one ostracod taxon (i.e. Heterocypris sp.), were not identified to species level and therefore deserve further study. The main ecological determinants of species distribution in the study area were examined using canonical multivariate analysis, which explained around 40% of total variation of the species similarity matrix; the main environmental drivers of crustacean assemblages in the study area were elevation, water turbidity, water temperature and electrical conductivity. The ecological preferences of crustacean species in the area are briefly discussed

    Ostracod valves as efficient UV protection

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    One of the major consequences of climate change is the increase of ultraviolet radiation, especially UVB (280-315 nm). This has important consequences for organisms and ecosystems. In surface freshwater ecosystems with transparent water, UV can easily penetrate deeply. Here, we used three different experimental approaches to examine the response of non-marine ostracods and cladocerans to UVB radiation: estimating lethal doses, determining how much UVB is blocked by the valves, and analysing valve chemical compositions. For most investigated crustaceans, we found a strong correlation between the amount of UVB that is blocked by the valves and the lethal UVB doses. Most ostracod valves blocked between 60% and 80% of UVB radiation, thus providing effective shielding. Pigmented species from temporary habitats were best protected. These species also showed high lethal UVB doses of 110 kJ m 2 to 214 kJ m 2. In the waterflea Daphnia magna, valves only stopped ca 35% of UVB radiation, and the lethal dose was half that of the doses estimated for ostracods. Since there were no significant differences in chemical composition of the valves between the investigated species, other factors must be responsible for the observed differences, which remain to be identified

    Variability in Environmental Conditions Strongly Impacts Ostracod Assemblages of Lowland Springs in a Heavily Anthropized Area

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    The Po river plain (Northern Italy) hosts artificial, lowland springs locally known as fontanili, which provide important ecosystem services in an area dominated by intensive agricultural activities. Here we present a study carried out in 50 springs. Each spring was visited once from October 2015 to January 2016. The sampled sites were selected to include springs studied in 2001 and 2004, to evaluate changes in water quality and ostracod assemblages that possibly occurred over a period of 10–15 years, and explore the relationships between ostracod community composition and water physical and chemical variables. Our results showed a decrease in the chemical water quality especially, in springs south of the Po river, evidenced by high nitrate levels. Most of the studied springs showed a relevant decrease in dissolved reactive silica, probably related to recent transformations of either agricultural practices or crop typology. Ostracods were mostly represented by common and tolerant species, and communities were characterized by low alpha diversity and high species turnover. Water temperature and mineralization level were the most influential variables in structuring the ostracod communities. We stress the need to implement conservation and restoration measures for these threatened ecosystems, to regain their role as ecosystem services providers

    Sheep brain atlas creation. Diffusion tensor imaging and Scanning electron microscope in sheep brain analysis

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    IntroductionsAim of EDEN 2020 project is the development of a steerable catheter for CED system in glioblastoma therapy. The VET group is involved in realization and validation of the proper animal model.For surgical planning purpose a Diffusion Tensor Imaging (DTI) of white matter tracts in the sheep is necessary to identify the target points useful for the catheter introduction.The analysis of the sheep brain under a Scanning Electron Microscope (SEM) is required to understand any alterations due to the catheter introduction and to fluids injection during CED administration. Materials and methodsAnimals were treated in accordance with the European Communities Council directive (86/609/EEC), to the laws and regulations on animal welfare enclosed in D.L.G.S. 26/2014A total of five 70 kg female, one year old, sheep were used for the study.All animals, under general anesthesia, underwent to Magnetic Resonance Imaging (MRI) acquisition. MRI scanner used was Philips Ingenia 1.5 Tesla system.Once the DTI imaging were acquired the animals were euthanased, sheep brain was collected and samples of white matter tracts obtained with disposable biopsy punches of 1.5-2 mm of diameter.The samples were fixed, stained in Osmium tetroxide (OsO4) and then embedded with two different protocols (cold curing vs thermal curing) in resin for the Focused Ion Beam (FIB) SEM analyses. Results and discussionAll the DTI images were uploaded to TrackVis software and major white matter fiber tracts analysed. Corticospinal tract, visual radiation, fornix and fronto-occipital fasciculus were identified.Corticospinal tract was identified as major white matter tract in sheep brain and useful as target area for the research aims.For the SEM analysis the thermal protocol was recognised as better curing methods for the research purpose than cold curing one. ConclusionThe data acquired in this study are still submitted to analysis. AcknowledgmentThe project has received funding from the European Union’s EU Research and Innovation programme Horizon 2020 (no 688279)

    Climate Change and Childhood Respiratory Health: A Call to Action for Paediatricians

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    Climate change (CC) is one of the main contributors to health emergencies worldwide. CC appears to be closely interrelated with air pollution, as some pollutants like carbon dioxide (CO2), nitrogen oxides (NOx) and black carbon are naturally occurring greenhouse gases. Air pollution may enhance the allergenicity of some plants and, also, has an adverse effect on respiratory health. Children are a uniquely vulnerable group that suffers disproportionately from CC burden. The increasing global warming related to CC has a big impact on plants' lifecycles, with earlier and longer pollen seasons, as well as higher pollen production, putting children affected by asthma and allergic rhinitis at risk for exacerbations. Extreme weather events may play a role too, not only in the exacerbations of allergic respiratory diseases but, also, in favouring respiratory infections. Even though paediatricians are already seeing the impacts of CC on their patients, their knowledge about CC-related health outcomes with specific regards to children's respiratory health is incomplete. This advocates for paediatricians' increased awareness and a better understanding of the CC impact on children's respiratory health. Having a special responsibility for children, paediatricians should actively be involved in policies aimed to protect the next generation from CC-related adverse health effects. Hence, there is an urgent need for them to take action and successfully educate families about CC issues. This paper aims at reviewing the evidence of CC-related environmental factors such as temperature, humidity, rainfall and extreme events on respiratory allergic diseases and respiratory infections in children and proposing specific actionable items for paediatricians to deal with CC-related health issues in their clinical practice

    Prognostication in palliative radiotherapy-ProPaRT: Accuracy of prognostic scores

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    BackgroundPrognostication can be used within a tailored decision-making process to achieve a more personalized approach to the care of patients with cancer. This prospective observational study evaluated the accuracy of the Palliative Prognostic score (PaP score) to predict survival in patients identified by oncologists as candidates for palliative radiotherapy (PRT). We also studied interrater variability for the clinical prediction of survival and PaP scores and assessed the accuracy of the Survival Prediction Score (SPS) and TEACHH score. Materials and methodsConsecutive patients were enrolled at first access to our Radiotherapy and Palliative Care Outpatient Clinic. The discriminating ability of the prognostic models was assessed using Harrell's C index, and the corresponding 95% confidence intervals (95% CI) were obtained by bootstrapping. ResultsIn total, 255 patients with metastatic cancer were evaluated, and 123 (48.2%) were selected for PRT, all of whom completed treatment without interruption. Then, 10.6% of the irradiated patients who died underwent treatment within the last 30 days of life. The PaP score showed an accuracy of 74.8 (95% CI, 69.5-80.1) for radiation oncologist (RO) and 80.7 (95% CI, 75.9-85.5) for palliative care physician (PCP) in predicting 30-day survival. The accuracy of TEACHH was 76.1 (95% CI, 70.9-81.3) and 64.7 (95% CI, 58.8-70.6) for RO and PCP, respectively, and the accuracy of SPS was 70 (95% CI, 64.4-75.6) and 72.8 (95% CI, 67.3-78.3). ConclusionAccurate prognostication can identify candidates for low-fraction PRT during the last days of life who are more likely to complete the planned treatment without interruption.All the scores showed good discriminating capacity; the PaP had the higher accuracy, especially when used in a multidisciplinary way
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