1,013 research outputs found

    A comparison of efficient permutation tests for unbalanced ANOVA in two by two designs--and their behavior under heteroscedasticity

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    We compare different permutation tests and some parametric counterparts that are applicable to unbalanced designs in two by two designs. First the different approaches are shortly summarized. Then we investigate the behavior of the tests in a simulation study. A special focus is on the behavior of the tests under heteroscedastic variances.Comment: 20 pages, 9 figures, Working Paper of the Department of Management And Enigineering of the University of Padov

    Expansion of cyanobacteria outbreaks in the Alpine region: first report of an intense Microcystis bloom in Lake Serraia

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    Lake Serraia is a small eutrophic dimictic lake located in the town of Baselga di Pinè, in the Province of Trento. The lake has an average depth of 7 m and a maximum depth of 18 m and is mainly used for recreational activities. During the last decade, summer blooms of non-toxigenic populations of Dolichospermum spp. were documented over the entire lake. Conversely, at the end of August 2023, an intense toxigenic bloom of Microcystis aeruginosa developed over several weeks, resulting in a bathing ban by the local authorities. Besides the usual monitoring for the control of bathing waters, a few opportunistic samples were collected for microscopical examinations, toxins analyses using LC-MS techniques, and strain isolation and cultivation. In the areas where the surface scums developed, the MC-LR and MC-RR congeners of microcystins showed concentrations of 200 μg L-1 and 42 μg L-1, respectively. The bloom episodes documented in Lake Serraia are part of a more general increasing trend of cyanobacterial outbreaks actively documented in the southern Alpine region. Besides persisting high trophic status, as in Lake Serraia, the causes were also connected to the general increasing temperature trends at the global and local levels

    Instancias narrativas en entrevistas de admisión: núcleo y estructura retórica de acciones verbales

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    The focus of my research is Narrative Instances (NIs) of Admission Interviews (AIs) in Public Mental Health carried out in Youth Centres of Mendoza Province, Argentina, within the framework of MOdEAS project. The aim of this paper is to show the functional relation between NIs and Verbal Actions (Paris 2012, 2009, Paris et al. 2008) that are expressed in the AIs: <complaint>, <victimisation>, <disqualification>, etc. Verbal Actions (VAs) are theoretical constructs that capture the interactional nature of conversations and are defined by an information structure based on five attributes. Paris (2012:3) argues that the abstract scheme used to define VAs can be realised in various and different ways. According to my hypothesis, the nucleus of VAs is expressed in the evaluative constituents of the different categories of NIs, which makes it possible to establish relationships between type of VA and type of appraisal (subsystem of attitude) (Martin y White 2005). I also sustain that non-evaluative constituents of NIs are the “rhetoric structure”, i.e. each of the non-evaluative constituents has a rhetoric function (Mann et al., 1992; Mann y Thompson, 1988; Paris, 2010) which contributes to the effective completion of the VA. In this paper, I illustrate the relation between nucleus and rhetorical structure of the VAs <complaint> (París 2012), <victimisation> and <disqualification> (Salmaso 2013) with a NI that belongs to the category Narrative. The focus of my research is Narrative Instances (NIs) of Admission Interviews (AIs) in Public Mental Health carried out in Youth Centres of Mendoza Province, Argentina, within the framework of MOdEAS project. The aim of this paper is to show the functional relation between NIs and Verbal Actions (Paris 2012, 2009, Paris et al. 2008) that are expressed in the AIs: <complaint>, <victimisation>, <disqualification>, etc. Verbal Actions (VAs) are theoretical constructs that capture the interactional nature of conversations and are defined by an information structure based on five attributes. Paris (2012:3) argues that the abstract scheme used to define VAs can be realised in various and different ways. According to my hypothesis, the nucleus of VAs is expressed in the evaluative constituents of the different categories of NIs, which makes it possible to establish relationships between type of VA and type of appraisal (subsystem of attitude) (Martin y White 2005). I also sustain that non-evaluative constituents of NIs are the “rhetoric structure”, i.e. each of the non-evaluative constituents has a rhetoric function (Mann et al., 1992; Mann y Thompson, 1988; Paris, 2010) which contributes to the effective completion of the VA. In this paper, I illustrate the relation between nucleus and rhetorical structure of the VAs <complaint> (París 2012), <victimisation> and <disqualification> (Salmaso 2013) with a NI that belongs to the category Narrative.&nbsp

    Active shape correction of a thin glass/plastic X-ray mirror

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    Optics for future X-ray telescopes will be characterized by very large aperture and focal length, and will be made of lightweight materials like glass or plastic in order to keep the total mass within acceptable limits. Optics based on thin slumped glass foils are currently in use in the NuSTAR telescope and are being developed at various institutes like INAF/OAB, aiming at improving the angular resolution to a few arcsec HEW. Another possibility would be the use of thin plastic foils, being developed at SAO and the Palermo University. Even if relevant progresses in the achieved angular resolution were recently made, a viable possibility to further improve the mirror figure would be the application of piezoelectric actuators onto the non-optical side of the mirrors. In fact, thin mirrors are prone to deform, so they require a careful integration to avoid deformations and even correct forming errors. This however offers the possibility to actively correct the residual deformation. Even if other groups are already at work on this idea, we are pursuing the concept of active integration of thin glass or plastic foils with piezoelectric patches, fed by voltages driven by the feedback provided by X-rays, in intra-focal setup at the XACT facility at INAF/OAPA. In this work, we show the preliminary simulations and the first steps taken in this project

    Considering mesohabitat scale in ecological impact assessment of sediment flushing

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    Benthic macroinvertebrates respond to several factors characterizing the physical habitats, as water depth, current and streambed substrate. Thus, anthropogenic disturbances altering these factors may have different effects on benthos, also depending on mesohabitats. These disturbances include sediment flushing operations, commonly carried out to recover reservoir capacity, and investigating their effects at mesohabitat scale could be relevant for an adequate ecological impact assessment of these operations. Here, we compared benthic macroinvertebrate communities sampled before and after a controlled sediment flushing operation in three different mesohabitats (a pool, a riffle and a step-pool) of an Alpine stream. Contrary from expectations, the composition of macroinvertebrate assemblages was not significantly different among mesohabitats. Moreover, the impact of sediment flushing was more significant in terms of density rather than in richness. Two stressor-specific indices were tested, but only one (the Siltation Index for LoTic EcoSystems - SILTES) clearly detected the impact of sediment flushing on the macroinvertebrate community structure. Finally, some differences in the temporal trajectories and recovery times to pre-flushing conditions were observed among mesohabitats, both if the three mesohabitats were considered separately and if all their possible combinations were accounted for. Particularly, riffle was the most sensitive mesohabitat, not fully recovering one year after the sediment disturbance

    Comparison of different methods for SNP detection in grapevine

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    Single nucleotide polymorphisms (SNPs) are the most abundant of all markers, both in animal and plant genomes. In crops and tree species considerable investment has been recently made on this genomic technology. While large-scale characterisation of SNPs by high-throughput techniques is possible, such highthroughput platforms are not available to all plant breeding laboratories. This report compares alternative multi-purpose and affordable methods for SNP assay in grapevine (Vitis spp.). In particular, the efficiency, sensitivity and reliability of single-strand conformation polymorphism (SSCP) on both non-denaturant gels and fluorescence-based capillary electrophoresis are compared with minisequencing (single nucleotide extension reaction). The results indicate that when multiplexing in combination with minisequencing is a mid-throughput, reliable and flexible technique for the detection of SNPs and can therefore be used effectively to improve marker assisted breeding in grapevine.
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