678 research outputs found

    Microplastics impair the feeding performance of a Mediterranean habitat-forming coral

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    none9siThe impact of plastic debris, and in particular of microplastics (here referred as particles smaller than 5 mm) on aquatic environments has now become a topic of raising concern. Microplastics are particularly abundant in the Mediterranean Sea, potentially exerting substantial pressures on marine organisms at different levels of organization. Ingestion of microplastics has been observed in a large number of marine species. The aim of this work is to test if microplastics produce a feeding impairment in Astroides calycularis, a shallow water, habitat-forming coral endemic to the Mediterranean Sea. Our findings suggest a lack of any avoidance mechanism allowing the polyps to discern between food items and microplastics when occurring simultaneously. Moreover, polyps spend a considerable amount of time on handling microplastic particles. As a consequence, microplastics impair the feeding efficiency in A. calycularis, since polyps may not be fully able to profit from the drifting plankton aggregations. Therefore, we suggest that microplastics can cause a reduction of fitness in A. calycularis, and presumably also in other species characterized by suspension feeding strategy.embargoed_20220123Savinelli B.; Vega Fernandez T.; Galasso N.M.; D'Anna G.; Pipitone C.; Prada F.; Zenone A.; Badalamenti F.; Musco L.Savinelli, B.; Vega Fernandez, T.; Galasso, N. M.; D'Anna, G.; Pipitone, C.; Prada, F.; Zenone, A.; Badalamenti, F.; Musco, L

    The rs1001179 SNP and CpG methylation regulate catalase expression in chronic lymphocytic leukemia

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    Chronic lymphocytic leukemia (CLL) is an incurable disease characterized by an extremely variable clinical course. We have recently shown that high catalase (CAT) expression identifies patients with an aggressive clinical course. Elucidating mechanisms regulating CAT expression in CLL is preeminent to understand disease mechanisms and develop strategies for improving its clinical management. In this study, we investigated the role of the CAT promoter rs1001179 single nucleotide polymorphism (SNP) and of the CpG Island II methylation encompassing this SNP in the regulation of CAT expression in CLL. Leukemic cells harboring the rs1001179 SNP T allele exhibited a significantly higher CAT expression compared with cells bearing the CC genotype. CAT promoter harboring the T -but not C- allele was accessible to ETS-1 and GR-β transcription factors. Moreover, CLL cells exhibited lower methylation levels than normal B cells, in line with the higher CAT mRNA and protein expressed by CLL in comparison with normal B cells. Methylation levels at specific CpG sites negatively correlated with CAT levels in CLL cells. Inhibition of methyltransferase activity induced a significant increase in CAT levels, thus functionally validating the role of CpG methylation in regulating CAT expression in CLL. Finally, the CT/TT genotypes were associated with lower methylation and higher CAT levels, suggesting that the rs1001179 T allele and CpG methylation may interact in regulating CAT expression in CLL. This study identifies genetic and epigenetic mechanisms underlying differential expression of CAT, which could be of crucial relevance for the development of therapies targeting redox regulatory pathways in CLL

    Italian Vascular Flora: New Findings, Updates and Exploration of Floristic Similarities between Regions

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    The tradition of floristic studies in Italy has made it possible to obtain a good knowledge of plant diversity both on a national and regional scale. However, the lack of knowledge for some areas, advances in plant systematics and human activities related to globalization, highlight the need for further studies aimed at improving floristic knowledge. In this paper, based on fieldwork and herbaria and literature surveys, we update the knowledge on the Italian vascular flora and analyze the floristic similarities between the administrative regions. Four taxa, all exotic, were recorded for the first time in Italy and Europe. In detail, Elaeodendron croceum, Kalanchoë blossfeldiana, and Sedum spathulifolium var. spathulifolium were found as casual aliens, while Oxalis brasiliensis was reported as historical record based on some herbarium specimens. Furthermore, Kalanchoë laxiflora was confirmed as a casual alien species for Italy and Europe. Status changes for some taxa were proposed at both national and regional levels, as well as many taxa were reported as new or confirmed at the regional level. Currently the Italian vascular flora comprises 9150 taxa of which 7547 are native (of which 1598 are Italian endemics) and 1603 are exotic at the national level. The multivariate analysis of updated floristic data on a regional scale showed a clear distribution along the latitudinal gradient, in accordance with the natural geographical location of the regions in Italy. This pattern of plants distribution was not affected by the introduction of alien species. Despite some taxonomic and methodological issues which are still open, the data obtained confirm the important role of floristic investigations in the field and in herbaria, as well as the collaborative approach among botanists, in order to improve the knowledge of the Italian and European vascular flora

    β2-Adrenergic receptor stimulation improves endothelial progenitor cell-mediated ischemic neoangiogenesis

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    Endothelial progenitor cells (EPCs) are present in the systemic circulation and home to sites of ischemic injury where they promote neoangiogenesis. β2-Adrenergic receptor (β2AR) plays a critical role in vascular tone regulation and neoangiogenesis

    Bulk-sensitive photoemission spectroscopy of A_2FeMoO_6 double perovskites (A=Sr, Ba)

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    Electronic structures of Sr_2FeMoO_6 (SFMO) and Ba_2FeMoO_6 (BFMO) double perovskites have been investigated using the Fe 2p->3d resonant photoemission spectroscopy (PES) and the Cooper minimum in the Mo 4d photoionization cross section. The states close to the Fermi level are found to have strongly mixed Mo-Fe t_{2g} character, suggesting that the Fe valence is far from pure 3+. The Fe 2p_{3/2} XAS spectra indicate the mixed-valent Fe^{3+}-Fe^{2+} configurations, and the larger Fe^{2+} component for BFMO than for SFMO, suggesting a kind of double exchange interaction. The valence-band PES spectra reveal good agreement with the LSDA+U calculation.Comment: 4 pages, 3 figure

    Structural and doping effects in the half-metallic double perovskite A2A_2CrWO6_6

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    he structural, transport, magnetic and optical properties of the double perovskite A2A_2CrWO6_6 with A=Sr, Ba, CaA=\text{Sr, Ba, Ca} have been studied. By varying the alkaline earth ion on the AA site, the influence of steric effects on the Curie temperature TCT_C and the saturation magnetization has been determined. A maximum TC=458T_C=458 K was found for Sr2_2CrWO6_6 having an almost undistorted perovskite structure with a tolerance factor f1f\simeq 1. For Ca2_2CrWO6_6 and Ba2_2CrWO6_6 structural changes result in a strong reduction of TCT_C. Our study strongly suggests that for the double perovskites in general an optimum TCT_C is achieved only for f1f \simeq 1, that is, for an undistorted perovskite structure. Electron doping in Sr2_2CrWO6_6 by a partial substitution of Sr2+^{2+} by La3+^{3+} was found to reduce both TCT_C and the saturation magnetization MsM_s. The reduction of MsM_s could be attributed both to band structure effects and the Cr/W antisites induced by doping. Band structure calculations for Sr2_2CrWO6_6 predict an energy gap in the spin-up band, but a finite density of states for the spin-down band. The predictions of the band structure calculation are consistent with our optical measurements. Our experimental results support the presence of a kinetic energy driven mechanism in A2A_2CrWO6_6, where ferromagnetism is stabilized by a hybridization of states of the nonmagnetic W-site positioned in between the high spin Cr-sites.Comment: 14 pages, 10 figure

    Supervoxel-Consistent Foreground Propagation in Video

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    Abstract. A major challenge in video segmentation is that the fore-ground object may move quickly in the scene at the same time its ap-pearance and shape evolves over time. While pairwise potentials used in graph-based algorithms help smooth labels between neighboring (su-per)pixels in space and time, they offer only a myopic view of consis-tency and can be misled by inter-frame optical flow errors. We propose a higher order supervoxel label consistency potential for semi-supervised foreground segmentation. Given an initial frame with manual annota-tion for the foreground object, our approach propagates the foreground region through time, leveraging bottom-up supervoxels to guide its es-timates towards long-range coherent regions. We validate our approach on three challenging datasets and achieve state-of-the-art results.

    Notulae to the Italian alien vascular flora: 3

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    In this contribution, new data concerning the Italian distribution of alien vascular flora are presented. It includes new records, exclusions, confirmations, and status changes for Italy or for Italian administrative regions for taxa in the genera Acer, Amaranthus, Araujia, Aubrieta, Avena, Bidens, Calycanthus, Celtis, Elaeagnus, Eragrostis, Euonymus, Fallopia, Ficus, Hedera, Lantana, Ligustrum, Ludwigia, Morus, Oenothera, Opuntia, Oxalis, Parkinsonia, Paspalum, Paulownia, Platycladus, Pleuropterus, Rumex, Salvia, Senecio, Setaria, Syagrus, Tradescantia, Trifolium and Yucca. Furthermore, a new combination in the genus Vicia is proposed
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