440 research outputs found

    Increase in airborne allergenic pollen in Trentino (North Italy): knowledge to adapt to climate change

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    Pollen allergy affects approximately 25% of adult and 40% of children globally (Nur Husna et al. 2022). Climate change is impacting allergenicity and pollen production, as well as the spread of neophytes that produce allergenic pollen, due to the combined effects of milder weather, air pollution, and elevated CO2 levels (Luschkova et al. 2022). As a result, there is an upward trend in allergic diseases (D’Amato et al. 2015). The study of pollen and its spatio-temporal changes is highly important due to the allergenicity of many airborne pollen taxa. Earlier-onset of pollen, the lengthening of the pollen season, and/or the increase in pollen quantities, can diminish the quality of life of allergic patients. In the "one health" perspective, we examine how climate change impact the ecosystem, affecting human well-being and health. Phenology, the science of natural recurring events, is one of the preferred indicators for observing the impacts of climate change on ecosystems and biological processes (Parmesan 2006). The shift in phenology is a high-temporal resolution signal of this impact and pollen dispersal is often used as a reliable proxy of flowering. This study describes the significant changes that have occurred to the airborne pollen component recorded in San Michele all’Adige, Northern Italy, from 1989 to 2018, analyzing a total of 24 arboreal (AP; trees and shrubs) and non-arboreal pollen taxa (NAP; herbaceous). Airborne pollen was collected using a volumetric Hirst-type aerobiological sampler (Lanzoni VPPS 2000), and the daily concentration of airborne pollen (P*m-3) was calculated for each taxon over a 30-year period from 1989 to 2018. The sampling and analysis of airborne pollen have been performed in accordance with the UNI EN 16868:2019 European standard procedure. The following pollen season descriptors were calculated for each taxon: (i) annual pollen integral (APIn; pollen*day*m-3); (ii) the start and end dates of the main pollen season (MPS), as the day of the year (DOY) when 2.5% and 97.5% of the APIn was reached, respectively; (iii) the length of the MPS, as the difference between the end and start DOY (+1); (iv) peak concentration; and (v) peak date, as the DOY when the maximum concentration was registered. The presence of a monotonic upward or downward temporal trend in pollen season descriptors was verified and changes were analyzed in relation to temperature, precipitation, and land use; in addition, pollen data were analyzed clustered into blocks of one decade each to minimize interannual fluctuations and maximize relevant change signals. The major result is an increase in pollen load (Fig. 1). All arboreal and shrub species (AP) and the majority of herbaceous (NAP) species had an impressive increase in pollen quantities. The extent of the increase in pollen load is evident when analyzing decadic blocks, with a relevant increase in the APIn for the total pollen spectrum, mostly due to AP taxa, with hop hornbeam and cypress family accounting for 49% of the increase (average on the 30-year period). Accordingly, AP shows a significant increase (+31 days) in the number of days with high pollen concentrations (i.e., > 100 pollen grains/m3). Such an increase in pollen quantity is unlikely to be related to changes in land use, given that the increase in forests and semi-natural areas is limited. The finding of an increase in APIn, especially marked for AP taxa, is consistent with previous studies and on a broader scale, from Europe (Ziello et al. 2012) to the entire Northern Hemisphere (Ziska et al. 2019). Moreover, some evidence of early start date for some taxa has been observed (e.g. Poaceae), at the same time as a longer pollen seasons for other taxa (e.g. Cupressaceae). A larger amount of pollen, an increase in the number of days with high pollen concentration, and an early start to the pollen season, which have been occurring since 1990 in the study area, all constitute a worsening situation and a major threat to people with pollen allergies. Thanks to these achievements it is possible to develop proposals for adaptation strategies that include as early stages: (i) development and implementation of risk communication strategies, (ii) implementation of good practices for green management. These proposals will be included in the Climate Change Adaptation Strategy of the Autonomous Province of Trento, which is currently being defined. Figures Fig 1: Increase of total arboreal pollen integral in the 30 years; detail for Ostrya (hop hornbeam) pollen taxonom

    Contributi italiani alla nascita della Petrografia

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    Verso la fine del XVIII e nei primi decenni del XIX secolo alcuni esperti italiani nella prospezione e sfruttamento minerario ed interessati nelle Scienze della Terra, G. Arduino, G. Marzari Pencati, G. Brocchi, e S. Breislak, hanno correttamente riconosciuto in base ad osservazioni sul campo la natura che oggi definiremmo magmatica di corpi sia intrusivi che vulcanici all'interno di sequenze sedimentarie, in contrasto con quanto previsto dalle teorie nettunistiche di Werner, allora dominanti. Ma anche celebrati studiosi di Storia Naturale, come L. Spallanzani e G. Gioeni hanno dato un importante contributo alle ricerche sulle rocce, ed al termine del periodo è da ricordare anche C. Gemmellaro, successore di Gioeni. La Petrografia si stava allora sviluppando, nella cornice della Storia Naturale, come disciplina autonoma dalla Mineralogia e dalla Geologia quando fu possibile classificare le rocce, già suddivise da Werner in gruppi fondati su criteri sistematici embrionalmente petrografici, sulla base dei primi fondamentali lavori di Cordier (1816), von Leonhard (1823) e Brongniart (1827), che hanno introdotto una tassonomia delle rocce, ancora affetta da inconsistenze ed ingenuità, in base alla loro composizione ed origine

    Separation of Ho3+ in Static Magnetic Field

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    Abstract The rare earths elements (REE) belong to the group of critical metals and they are achieving more and more interest due to their special properties. However, there occur some problems connected with their production. The most difficult phase is separation of REE. It includes a necessity to intensify currently applied processes and looking for new solutions. The present work introduces an idea to use differences in physical properties of the REE ions to get them separated. In the experimental part of the work some efforts were undertaken to analyse results presenting changes of holmium ions concentration under an influence of the magnetic field gradient. There was determined the gradient of magnetic field and concentration of Ho3+ ions depending on initial concentration of the solution and time. A simulation of changing the concentration of holmium ions in the solution under an influence of the magnetic field gradient was performed to compare the mathematical model with the obtained results

    Statistical properties and morphology of a 2D gel network at the air/water interface

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    We report here a detailed characterization of the steps leading to the formation of a bidimensional gel at the air/water interface. The 2D geometry is peculiar in that it allows a continuous and controlled variation of the density of the system over a wide range. The evolution of the statistical properties of the structured network, as a function of the externally controlled density, is related to the corresponding evolution of the mechanical properties. We identified three steps in the gel formation: a first step occurs in the incubation time, in which the individual nm-sized gold nanoparticle aggregate to form quasi 1D structures of typical length of a few microns. The second step occurs in the first stages of the compression, with the growth of the branched structure, finally yielding to the onset of the infinite percolative cluster, which is related to the building of the mechanical elastic modulus. The final step identifies with the homogenization and regularization of the distribution of holes sizes, which relates to the further increase of the elastic modulus upon compression. We speculate that this study should help in the formulation of gels with desired characteristics, such as increased mechanical strength, or increased mobilit

    The Source Characteristics of Mt. Etna Magmas Erupted During the Last 60 ka

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    Primary stability of a press-fit cup in combination with impaction grafting in an acetabular defect model

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    The objectives of this study were to (a) assess primary stability of a press-fit cup in a simplified acetabular defect model, filled with compacted cancellous bone chips, and (b) to compare the results with primary stability of a press-fit cup combined with two different types of bone graft substitute in the same defect model. A previously developed acetabular test model made of polyurethane foam was used, in which a mainly medial contained defect was implemented. Three test groups (N = 6 each) were prepared: Cancellous bone chips (bone chips), tricalciumphosphate tetrapods + collagen matrix (tetrapods + coll), bioactive glass S53P4 + polyethylene glycol-glycerol matrix (b.a.glass + PEG). Each material was compacted into the acetabulum and a press-fit cup was implanted. The specimens were loaded dynamically in the direction of the maximum resultant force during level walking. Relative motion between cup and test model was assessed with an optical measurement system. At the last load step (3000 N), inducible displacement was highest for bone chips with median [25th percentile; 75th percentile] value of 113 [110; 114] µm and lowest for b.a.glass + PEG with 91 [89; 93] µm. Migration at this load step was highest for b.a.glass + PEG with 868 [845; 936] µm and lowest for tetrapods + coll with 491 [487; 497] µm. The results show a comparable behavior under load of tetrapods + coll and bone chips and suggest that tetrapods + coll could be an attractive alternative to bone chips. However, so far, this was found for one specific defect type and primary stability should be further investigated in additional/more severe defects

    Apoptosis and cell proliferation in porcine placental vascularization

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    The placenta is a highly vascularized organ, indispensable tothe transfer of nutrients to the growing fetuses. During gestation, there exists an expansion of the placental vascular network through active angiogenesis. The aim of this research was to study cell proliferation and apoptosis through high resolution light microscopy (HRLM) and transmission electron microscopy (TEM) ultrastructure, immunohistochemistry for Ki67and caspase-3, determination of placental vascular area,and TUNEL assay. Crossbred sows placental tissues from approximately 30 ± 2(n =5), 40 ± 2(n =5), 60 ± 2 (n =5), 80 ± 2(n =5), 90 ± 2(n =5) and 114 ± 2(n =5) days of gestation were used. The evaluation of cell proliferation showed the highest%Ki67 values on days 30 ± 2 and 80 ± 2 of pregnancy. Caspase-3 expressed the highest value on day 30 ± 2, while the highest apoptotic indexes were found on days30 ± 2 and 90 ± 2. The placental vascular area was higher on day 80 ± 2 of pregnancy. According to our results, an active vascular cell remodeling by a caspase-3 dependent apoptosis seems to be present in early pregnancy. The increase in the vascular area on day 80 ± 2 would be the result of the intense vascular cell proliferation detected with Ki67. Further studies are needed to understand the complex processes of angiogenesis, cell proliferation and apoptosis that interact in the placenta during porcine gestation.Facultad de Ciencias Veterinaria

    Multiscale Bone Remodelling with Spatial P Systems

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    Many biological phenomena are inherently multiscale, i.e. they are characterized by interactions involving different spatial and temporal scales simultaneously. Though several approaches have been proposed to provide "multilayer" models, only Complex Automata, derived from Cellular Automata, naturally embed spatial information and realize multiscaling with well-established inter-scale integration schemas. Spatial P systems, a variant of P systems in which a more geometric concept of space has been added, have several characteristics in common with Cellular Automata. We propose such a formalism as a basis to rephrase the Complex Automata multiscaling approach and, in this perspective, provide a 2-scale Spatial P system describing bone remodelling. The proposed model not only results to be highly faithful and expressive in a multiscale scenario, but also highlights the need of a deep and formal expressiveness study involving Complex Automata, Spatial P systems and other promising multiscale approaches, such as our shape-based one already resulted to be highly faithful.Comment: In Proceedings MeCBIC 2010, arXiv:1011.005

    Evidence for distinct polymer chain orientations in KC60 and RbC60

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    The KC60 and RbC60 polymer phases exhibit contrasting electronic properties while powder diffraction studies have revealed no definite structural difference. We have performed single crystal X-ray diffraction and diffuse scattering studies of these compounds. It is found that KC60 and RbC60 possess different chain orientations about their axes, which are described by distinct space groups Pmnn and I2/m, respectively. Such a structural difference will be of great importance to a complete understanding of the physical properties.Comment: To be published in Phys. Rev. Let
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