2,268 research outputs found

    Predator and detritivore niche width helps to explain biocomplexity of experimental detritus-based food webs in four aquatic and terrestrial ecosystems

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    In the study of food webs, the existence and explanation of recurring patterns, such as the scale invariance of linkage density, predator–prey ratios and mean chain length, constitute long-standing issues. Our study focused on litter-associated food webs and explored the influence of detritivore and predator niche width (as d13C range) on web topological structure. To compare patterns within and between aquatic and terrestrial ecosystems and take account of intra-habitat variability, we constructed 42 macroinvertebrate patch-scale webs in four different habitats (lake, lagoon, beech forest and cornfield), using an experimental approach with litterbags. The results suggest that although web differences exist between ecosystems, patterns are more similar within than between aquatic and terrestrial web types. In accordance with optimal foraging theory, we found that the niche width of predators and prey increased with the number of predators and prey taxa as a proportion of total taxa in the community. The tendency was more marked in terrestrial ecosystems and can be explained by a lower per capita food level than in aquatic ecosystems, particularly evident for predators. In accordance with these results, the number of links increased with the number of species but with a significantly sharper regression slope for terrestrial ecosystems. As a consequence, linkage density, which was found to be directly correlated to niche width, increased with the total number of species in terrestrial webs, whereas it did not change significantly in aquatic ones, where connectance scaled negatively with the total number of species. In both types of ecosystem, web robustness to rare species removal increased with connectance and the niche width of predators. In conclusion, although limited to litter-associated macroinvertebrate assemblages, this study highlights structural differences and similarities between aquatic and terrestrial detrital webs, providing field evidence of the central role of niche width in determining the structure of detritus-based food webs and posing foraging optimisation constraints as a general mechanistic explanation of food web complexity differences within and between ecosystem types

    An Overview of the Automated and On-Line Systems to Assess the Oxidative Potential of Particulate Matter

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    Recent years have seen a significant increase in the scientific literature related to various methods for analyzing oxidative potential (OP) of atmospheric particulate matter (PM). The presence of several types of PM, differing chemical and physical properties, released by both anthropogenic and natural sources, leads to numerous health issues in living organisms and represents an attractive target for air quality monitoring. Therefore, several studies have focused on developing rapid and self-operative tests, employing different target molecules to assess OP of atmospheric aerosols as well as unique approaches to overcome some of the most common laboratory-related issues in this kind of analysis. This work provides an overview of online and automated systems, as well as a broad picture of the state-of-art of the various devices and methods developed on this topic over the last two decades. Moreover, representative studies on this subject will be discussed, analyzing the advantages and drawbacks of the developed automated techniques

    LaCulturaNonSiFerma -- Report su uso e la diffusione degli hashtag delle istituzioni culturali italiane durante il periodo di lockdown

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    This report presents an analysis of #hashtags used by Italian Cultural Heritage institutions to promote and communicate cultural content during the COVID-19 lock-down period in Italy. Several activities to support and engage users' have been proposed using social media. Most of these activities present one or more #hashtags which help to aggregate content and create a community on specific topics. Results show that on one side Italian institutions have been very proactive in adapting to the pandemic scenario and on the other side users' reacted very positively increasing their participation in the proposed activities.Comment: in Italia

    ItaGLAM: A corpus of Cultural Communication on Twitter during the Pandemic

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    This paper describes the compilation and annotation of ItaGLAM, a corpus of tweets written by Italian Galleries, Libreries, Archives and Museums (GLAMs) during the lockdown period in Italy due to the COVID-19 pandemic. ItaGLAM has been annotated with a set of labels which may be useful to identify different types of communication. Furthermore, the collected data have been used to train a set of classifiers.The results are analyzed to evaluate the information flow between GLAM and users and to analyze cultural communication on the Web

    Distretti industriali e Istituzioni Locali

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    Nascita ed evoluzione dei distretti industriali Rapporto tra istituzioni e distretti industriali Fattori istituzionali e contesto socio-economico Due casi a confronto: Solofra e Mirandol

    Comparison of Antibiotic Resistance Profile and Biofilm Production of Staphylococcus aureus Isolates Derived from Human Specimens and Animal-Derived Samples

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    Background: The diusion of antimicrobial resistance is a significant concern for public health worldwide. Staphylococcus aureus represents a paradigm microorganism for antibiotic resistance in that resistant strains appear within a decade after the introduction of new antibiotics. Methods: Fourteen S. aureus isolates from human specimens and twenty-one from samples of animal origin, were compared for their antimicrobial resistance and biofilm capability. In addition, they were characterized at the molecular level to detect the antimicrobial resistance mecA gene and genes related with enterotoxin, toxin, and biofilm production. Results: Both phenotypic and molecular analysis showed main dierences among human- and animal-derived isolates. Among the human-derived isolates, more multidrug-resistant isolates were detected and mecA gene, enterotoxin, and toxin genes were more prevalent. Dierent genes involved in biofilm production were detected with bap present only in animal-derived isolates and sasC present in both isolates, however, with a higher prevalence in the human-derived isolates. Biofilm capability was higher in human-derived isolates mainly associated to the sasC gene. Conclusions: The overall results indicate that human S. aureus isolates are more virulent and resistant than the isolates of animal origin randomly selected with no infection anamnesis. This study confirms that selection for more virulent and resistant S. aureus strains is related to the clinical practice

    Multiple Sclerosis And Maternity: A Psychological Explorative Qualitative Research

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    Considering women living with multiple sclerosis (MS), motherhood may represent a complicated event. Our aim in this study is to explore the personal meanings related to maternity and illness in women living with this disease. We have involved twenty women suffering from MS and we have administered an open interview introduced by a trigger question as a prompt aimed to elicit a narrative of their experience of illness, wishes, doubts, fears and life-projects with regard to motherhood. The interviews were audio-recorded and transcribed verbatim in order to carry out an analysis of the textual corpus. We have performed the textual analysis of the transcribed interviews through the T-LAB software. Performing a cluster analysis, four thematic clusters emerged: Daily Pain, Relationship with Health Care Services, Closing of a Circle and Family Role. We have interpreted the relationship between these themes using factorial mapping through 3 meaning vectors, representative of the following dynamics: From Concrete to Abstract; From Life-Project to Relapse; From Health Agencies to Family Support. All these meaning-vectors seem to describe the relationship between maternity and illness. Some aspects, as the presence of a stable partner or knowing diagnosis for more than ten years, might represent supporting factors for a project of motherhood. Starting from the results obtained, we provide some proposals for the definition of goals and strategies of psychological counselling within the Health Care Services

    A case of pulmonary edema: The critical role of lung-heart integrated ultrasound examination.

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    Cardiogenic pulmonary edema is a common presentation of acute heart failure normally treated with continuous positive airway pressure (CPAP), diuretics and nitrates. This therapy is contraindicated in case of cardiac tamponade. We describe a case of pulmonary edema due to cardiac tamponade in which integrated lung-heart ultrasound examination allowed prompt diagnosis and pericardiocentesis before administration of CPAP thus avoiding circulatory collapse
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