635 research outputs found

    Bayesian network semantics for Petri nets

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    Recent work by the authors equips Petri occurrence nets (PN) with probability distributions which fully replace nondeterminism. To avoid the so-called confusion problem, the construction imposes additional causal dependencies which restrict choices within certain subnets called structural branching cells (s-cells). Bayesian nets (BN) are usually structured as partial orders where nodes define conditional probability distributions. In the paper, we unify the two structures in terms of Symmetric Monoidal Categories (SMC), so that we can apply to PN ordinary analysis techniques developed for BN. Interestingly, it turns out that PN which cannot be SMC-decomposed are exactly s-cells. This result confirms the importance for Petri nets of both SMC and s-cells.Fil: Bruni, Roberto. Universit脿 degli Studi di Pisa; ItaliaFil: Melgratti, Hernan Claudio. Consejo Nacional de Investigaciones Cient铆ficas y T茅cnicas. Oficina de Coordinaci贸n Administrativa Ciudad Universitaria. Instituto de Investigaci贸n en Ciencias de la Computaci贸n. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaci贸n en Ciencias de la Computaci贸n; ArgentinaFil: Montanari, Ugo. Universit脿 degli Studi di Pisa; Itali

    Part II Farmers鈥 Experiences of the Farm Assessment: Interviews with Farmers

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    The objective of work package 463 was to test the implementation of the WQ assessment Scheme on regular broiler farms. We assessed the perception and attitudes of farmers towards animal welfare and on-farm assessment, the experience and evaluation of the assessment itself and the relevance and applicability of the results. at the same time animal scientists assessed the welfare of the animals by WQ monitoring instruments. In addition they scored foot pad lesions at the slaughterhouse by way of video imaging. Both studies proceeded in parallel; farmers told, hence, about their real-life experience. It is to be noted that the WQ monitoring instruments were not at their final state, and experiences and comments of the farmers are to be interpreted as reflection and discussion on work in progress. A team of sociologists carried out the study on farmers鈥 experiences, perception and attitude whereas the assessment of animal welfare was done by animal scientists. the study took place in three countries 鈥 Netherlands, Italy and the UK. We choose to focus on broilers for two main reasons. First of all the production cycle of broilers is relatively short and so it is possible to assess the welfare of different flocks within a short time-span and to check more easily any improvement of animal welfare as a result of farmers鈥 interventions. a second reason for focusing on broilers is that it allows us to link this project to another project where a new way of checking for foot-pad lesions is developed. this is, moreover, a relatively easy manner of checking animal welfare that allows us to lower the burden of three on-farm assessments considerably. In the following we report on the results of the welfare assessment (Part I) and the interviews with farmers about their perception and experience of animal welfare and the welfare assessment (Part II). In both parts we compare the results across the participating countries (Netherlands, Italy and United Kingdom). More in detail information on the national results of welfare assessment and interviews with farmers can be found in the deliverables 4.31.a (farmers鈥 interviews) and D4.31b (assessment results). as appendixes, we provide the technical and sociological questionnaires and the assessment reports that were sent to the farmers in the different countries. Bettina B. Bock Ingrid de Jon

    Ciliate diversity and behavioural observations from the chemoautotrophic cave ecosystem of Frasassi, (Marche region, Italy)

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    Chemoautotrophic cave organisms require specific adaptations to tolerate the stress of living in extreme environmental conditions, such as darkness, nutrient and energy limitations, low temperatures (12-13掳C), highly variable sulphide concentrations (from 0 up to 415 渭M H2S) and toxic levels of gases (H2S, CO2, CH4). To date, due to the difficulties in sampling in such harsh environment, very few studies were performed in order to describe the ciliate communities from caves; these have remained largely unexplored. Thus, the main aims of our study were to characterize for the first time, the ciliates from the sulfide-rich Frasassi cave complex (Marche region, Italy) and to observe possible behavioural differences with their non-cave-dwelling counterpart ciliate species. Four main sampling sites within Frasassi caves were selected: Pozzo dei Cristalli, Lago Verde, Ramo Solfureo and Grotta Solfurea. The ciliate diversity from the site Pozzo dei Cristalli was studied in greater detail for its spatio-temporal distribution, since it is highly diversified and includes several microhabitats represented by small sulfidic (H2S-rich) ponds, streams and springs as well as, deep and shallow muddy, stagnant lakes. Periodic sampling was realised from 2009 to 2011 in the form of water-sediments, picked up by scraping the surface. Classical culturing, silver staining methods and 18S rRNA gene (for some selected species) for phylogenetic analysis were employed. A total of 31 species belonging to 9 classes, 15 orders and 23 genera were identified. Fluctuation of the ciliate communities were mainly recorded at the Pozzo dei Cristalli sites during various sampling occasions, this could be due to changing environmental conditions (mainly H2S concentrations and water levels). Interestingly, it was observed that some species e.g. Urocentrum turbo, Coleps hirtus hirtus, Oxytricha sp, Euplotes sp, showed adaptation for the cave environment (photo-sensitivity, sulphur tolerance, feeding behaviour, morphological difference). Overall, these results provide a platform for various in-depth studies of ciliates to understand potential role in aquatic microhabitats, nature of chemical compounds secreted, dispersal pattern, and adaptations to cave environment

    Free living ciliated protists from the chemoautotrophic cave ecosystem of Frasassi (Italy)

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    This study provides the first report on a community of free-living ciliated protists from the chemoautotrophic cave ecosystem of Frasassi, Italy. This subterranean groundwater ecosystem represents a hotspot of biodiversity that still needs to be fully explored with particular reference to microbial eukaryotes such as protist ciliates. A total of 33 taxa of ciliates were identified along with one species each of flagellate, heliozoans and naked amoebae, from four main sampling sites, namely, Grotta Solfurea (GSO), Lago Verde (LVE), Ramo Solfureo (RSO), and Pozzo dei Cristalli (PDC). The last consists of small microhabitats/ponds presenting different chemical鈥損hysical and biological parameters, such as sulfur and nutrient contents and the presence of bacterial biofilms. Furthermore, an analysis of the cryptic ciliate species biosphere as a 鈥榮eedbank鈥 of diversity against cave ecosystem disturbance was also performed. This study also highlights some peculiar adaptations of cave-dwelling ciliates not described in their noncave-dwelling conspecifics, such as the extreme photosensitivity of Urocentrum turbo, the cannibalism of Coleps hirtus, the variable number of thorns in Aspidisca species as a defensive response to predation, and the frequent reorganization of ciliary structures in Euplotes aediculatus. The 18S rDNA sequences were generated for five species and were compared with those of the noncave-dwelling conspecifics. Finally, our results shed light on the still largely unknown ciliate diversity in the chemosynthesis-based sulfidic groundwater ecosystem of Frasassi

    Chemical Variability and Biological Activities of Volatile Oils from Hyptis suaveolens (L.) Poit.

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    Hyptis suaveolens (L.) Poit. belongs to the Lamiaceae family and is widely used in folk medicine in various countries. Th e essential oils from H. suaveolens have been extensively investigated and are mainly composed of monoterpenes and sesquiterpenes, although significant diterpene content has been reported in recent studies. The survey of the literature concerning H. suaveolens essential oils revealed a high level of chemical variability in terms of quantity and composition that is commonly observed for volatile oils from other plant species. However, few researchers have dealt with the reasons for such chemical variability. Our research group has been investigating the relationships between growing conditions of the plants and the H. suaveolens (L.) Poit. essential oil composition. The results of these investigations have led to some advances in the characterization and knowledge of H. suaveolens chemotypes from Brazil. Nevertheless, since this species presents high level of genetic polymorphism and allows it to adapt to the alterations in environmental features resulting in interpopulational and intrapopulational variability in the volatile oil chemical compositions. Consequently, biochemical assays on the biosynthetic pathway are required in order to detect the molecular mechanisms involved in inducing differential terpenoid biosynthesis within H. suaveolens. These are some of the challenges which require resolution leading to an understanding of the complex secondary metabolism of this species, thereby making possible the volatile oil chemical standardization seeking productivity and phytotherapy