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Using SVG and XSLT for graphic representation
Using SVG and XSLT for graphic representation
In this paper we will present an XML based framework that can be used to produce graphical visualisation of scientific data. The approach rather than producing ordinary histogram and function diagaram graphs, tries to represent the information in a more graphical appealing and easy to understand way. For examples the approach will give the ability to represent the temperature as the level of coulored fluid in a thermometer.
The proposed framework is able to maintain the value of the datas strictly separated from the visual form of its representation (positions of element, colours, visual representation etc.).
By defining appropriate data structures and expressing them using XML, the framework gives the user the ability to create graphic representations using standard SVG and XSLT.
Since XML can be used for describing complex data information, we represent every level of the graphic representation with an XML structure.
To describe our architecture we defined the following XML dialects, each one with different markup tags, reflecting the semantical values of the elements.
Data definition level. Used to define the value of the datas that can be used in the graphic representation
Data representation level. Used to define the graphic representation, it defines how the values expressed by the data definition level are represented.
Both data representation and data definition files are based on a DTD to impose the constraints.
Data representation level is the core of the system, and defines a powerful language for representation.
Source primitives. Used to define for the source of the graphic elements, for example static file or SVG code.
Modification primitives. Used to define the modifications that can affect a graphic element, for example rotation, scaling or repetition.
Disposition primitives. Used to define the possible dispositions along x, y and z axes, for example to impose a order in the representation of elements.
Action primitives. Used to define the possible actions that canbe activated by graphic elements for different user behaviours. For example a mouse action can activate a link to a different resource, or can change the value of any of the other primitives of the data structure, as image source or disposition, or can show a tooltip .
XSLT is used to output a SVG file derived from the two files describing the graphic representation.
Our aim is to provide an abstract language to be used to represent in different ways the same concept. In fact, we can link a data definition file with different data representation levels, providing different kinds and levels of complexity for the same concept. An example use could be the representation of the temperature described before, where the temperature itself could be represented either as the level of mercury in the termomether, or as the rotation of an arrow in a gauge.
The transformation process is made from an XML source tree into an XML result tree, using XPath to define patterns. XSLT transformation process is based on templates, that define some actions (like adding or removing elements, or sorting them) to be performed when a part of the document matches a template.
To implement some of the complex graphics operations we are using XSLT extensions that allow to perform mathematical operations.
These XSLT extensions are not yet standard and require specific compliant parser, as Apache Xalan, that allows the developer to interface with Java classes in order to increase XSLT areas of application, from simple node transformations to quite complex operations
NA62 sensitivity to heavy neutral leptons in the low scale seesaw model
The sensitivity of beam dump experiments to heavy neutral leptons depends on
the relative strength of their couplings to individual lepton flavours in the
Standard Model. We study the impact of present neutrino oscillation data on
these couplings in the minimal type I seesaw model and find that it
significantly constrains the allowed heavy neutrino flavour mixing patterns. We
estimate the effect that the DUNE experiment will have on these predictions. We
then discuss implication that this has for the sensitivity of the NA62
experiment when operated in the beam dump mode and provide sensitivity
estimates for different benchmark scenarios. We find that the sensitivity can
vary by almost two orders of magnitude for general choices of the model
parameters, but depends only weakly on the flavour mixing pattern within the
parameter range that is preferred by neutrino oscillation data.Comment: 29 pages, 8 figures, 3 tables, version accepted by JHE
Perspectives to find heavy neutrinos with NA62
The sensitivity of beam dump experiments to heavy neutrinos depends on the
relative size of their mixings with the lepton flavours in the Standard Model.
We study the impact of present neutrino oscillation data on these mixing angles
in the minimal type I seesaw model. We find that current data significantly
constrains the allowed heavy neutrino flavour mixing patterns. Based on this,
we discuss the implications for the sensitivity of the NA62 experiment to heavy
neutrinos when operated in the beam dump mode. We find that NA62 is currently
the most sensitive experiment in the world for heavy neutrino masses between
that of the kaon and the -mesons. The sensitivity can vary by almost two
orders of magnitude if the heavy neutrinos exclusively couple to the tau
flavour, but depends only comparably weakly on the flavour mixing pattern
within the parameter range preferred by light neutrino oscillation data.Comment: Contribution to the proceedings of the 53rd Rencontres de Moriond on
Electroweak Interactions and Unified Theories (2018). 6 pages, 2 figure
Oxidative stress and lateral muscle development in Siberian Sturgeon (Acipenser baeri): preliminary observations.
Embryonic development in bony fish is strongly influenced by environmental factors, mainly by temperature and dissolved oxygen, but little is known about their influence on Sturgeons. Since 1998 the international trade of Sturgeons has been regulated under CITES due to depletion of wild stocks. Sturgeon aquaculture as well as larvae production is, therefore, important because it may contribute to the repopulation of the wild stocks (Bronzi et al., 2011; Di Giancamillo et al., 2012).The aim of this study is to monitor oxidative stress status and muscle development during embryonic and precocious larval phases in Siberian Sturgeon (Acipenser baeri), when subjected to different incubating temperatures (13°, 16° and 19°C).Siberian sturgeon eggs were subjected to different incubation temperatures. Data regarding water quality parameters were recorded, as well as mortalities, embryonic period length, and precocious larvae behavior. Sampling was performed in the same developmental stage for each temperature, at five time points: 48 hours post-fertilization, embryo movements, hatching, schooling and yolk-sac full absorption. The observed hatching rates were between 85.5% and 98.8% with significant differences concerning the different experimental temperatures (T19 vs T13 and T19 vs T16, p<0,05). Histological, histochemical and immunohistochemical analyses will be performed to assess ontogeny of the lateral muscle and stress biomarkers (Lushchak, 2011), and gene expression will be analyzed for muscle development (Johnston, 2006). The obtained results will be compared with those concerning teleosts and will possibly contribute to better rearing conditions of sturgeons.This study has been approved by the ethic committee of the Università degli Studi di Milano, with the following authorisation code: OPBA_20_2016.
Effect of different stocking densities on growth, muscle development and fatty acid profile of Acipenser baerii larvae
Sturgeons, as well as paddlefishes, belong to the Acipenseriformes group, which is one of the most primordial 57 orders of the Osteichthyes that comprehends 25 species spread throughout Europe, Asia and North America. The present study aims at investigating muscle growth and development as well as fatty acid profile in Siberian sturgeon free-embryos when subjected to three different rearing densities. Fatty acids, in particular polyunsaturated fatty acids of n-3 series, are generally known as key nutrients in fish larvae.This study was approved by the Ethic Committee of the University of Milan (OPBA_22_2017). Siberian sturgeon larvae were reared at 18°C, at three stocking densities until complete yolk-sac absorption: low (LD, 30 larvae/l), mid (MD, 80 larvae/l) and high (HD, 150 larvae/l). Sampling timepoints were: hatching, schooling and complete yolk-sac absorption stage (YSA). Sacrificed larvae were weighed and histological analyses were performed in order to assess muscle development as described elsewhere ; fatty acid profile was determined by GC-FID analysis as described by Vasconi et al. (2015). Statistical analysis was performed with SAS software (v. 9.3, Cary Inc., NC).At the end of the experiment, LD larvae presented a higher weight than larvae reared at the other two densities (P<0.05). Within the schooling stage (Figure 1), Total Muscle Area was lower for HD larvae (P<0.05); red and white muscle areas in schooling and YSA were higher than at hatching (P<0.05), regardless the density. Concerning fatty acids, no statistical differences were recorded between different rearing densities, while during the development regardless the rearing density, there was a common pattern: linoleic and alfa linolenic acids, significantly decreased their relative content, while others, as arachidonic acid and DHA, significantly increased. Siberian sturgeon larvae reared at LD or MD reveal an anatomically normal muscle development, while in the HD it is possible to observe a slowdown.What the aquaculture industry requires is a set of guidelines that allows the development of a sustainable industry, so that we tried to develop guidelines for stocking density in the very early stage of farming. As a conclusion, it would seem that mid density could be more suitable for this species in this stage of development
Spatial and temporal phylogeny of border disease virus in pyrenean chamois (Rupicapra p. Pyrenaica)
Border disease virus (BDV) affects a wide range of ruminants worldwide, mainly domestic sheep and goat. Since 2001 several outbreaks of disease associated to BDV infection have been described in Pyrenean chamois (Rupicapra pyrenaica pyrenaica) in Spain, France and Andorra. In order to reconstruct the most probable places of origin and pathways of dispersion of BDV among Pyrenean chamois, a phylogenetic analysis of 95 BDV 5'untranslated sequences has been performed on chamois and domestic ungulates, including novel sequences and retrieved from public databases, using a Bayesian Markov Chain Monte Carlo method. Discrete and continuous space phylogeography have been applied on chamois sequences dataset, using centroid positions and latitude and longitude coordinates of the animals, respectively.
The estimated mean evolutionary rate of BDV sequences was 2.9x10(-3) subs/site/year (95% HPD: 1.5-4.6x10(-3)). All the Pyrenean chamois isolates clustered in a unique highly significant clade, that originated from BDV-4a ovine clade. The introduction from sheep (dated back to the early 90s) generated a founder effect on the chamois population and the most probable place of origin of Pyrenean chamois BDV was estimated at coordinates 42.42 N and 1.9 E. The pathways of virus dispersion showed two main routes: the first started on the early 90s of the past century with a westward direction and the second arise in Central Pyrenees. The virus spread westward for more than 125 km and southward for about 50km and the estimated epidemic diffusion rate was about 13.1 km/year (95% HPD 5.2-21.4 km/year). The strong spatial structure, with strains from a single locality segregating together in homogeneous groups, and the significant pathways of viral dispersion among the areas, allowed to reconstruct both events of infection in a single area and of migrations, occurring between neighboring areas
Rearing temperature effect on the skeletal muscle fibres of Acipenser baerii yolk-sac larvae
Siberian sturgeon farming is important because it provides an alternative source of caviar and meat, but also for the conservation of the endangered natural stocks. Farmed fish is continuously subjected to stress factors, of which, water temperature is considered a major one (Schram et al., 2006). It has been demonstrated that physiological stress may have serious negative consequences on growth (Wendelaar Bonga, 1997) and that fish larvae appear less tolerant than adults to temperature variations (Stefanovich et al., 2016). The present study aims at investigating the stress response and development in precocious stages of siberian sturgeon when subjected to different rearing temperatures, by analysing ontogeny, growth and stress response of yolk-sac larvae. This study was approved by the Ethic Committee of the University of Milan (OPBA_20_2016). Fertilized Siberian sturgeon eggs were reared at 16°C, 19°C and 22°C until complete yolk-sac absorption. Sampling timepoints were: hatching, schooling and complete yolk-sac absorption stage. Water parameters and larvae development data were registered. Histological, histochemical and immunohistochemical analyses were performed in order to assess ontogeny and stress biomarkers and whole body cortisol was measured by a specific microtitre radioimmunoassay (RIA). Statistical analysis was performed with SAS software (v. 9.3, Cary Inc., NC). Larvae subjected to the highest water temperature showed a faster yolk-sac absorption and larvae body weight significantly increased from hatching onwards. Structural normal development considering the three different temperatures investigated from hatching until the end of the trial was observed. Significant differences were found between temperatures regarding body weight and cortisol levels (P<0.01). A qualitative stronger expression of stress markers was noticed in larvae subjected to the lower temperature. Even if this study indicates that lower rearing temperatures would appear more suitable for Siberian sturgeon rearing, further studies would be necessary to evaluate the temperature effect on a mid-long term basis
Platinum, Palladium and Rhodium deposition to the Prunus laurus cerasus leaf surface as an indicator of the vehicular traffic pollution in the city of Varese area. An easy and reliable method to detect PGEs released from automobile catalytic converters
Background, aim, and scope The widespread use of some Platinum Group Elements (PGE) as catalysts to minimize emission of pollutants from combustion engines produced a constantly growing increase of the concentration of these elements in the environment; their potential toxicological properties explain the increasing interest in routine easy monitoring. We have found that leaves of Prunus laurus cerasus are efficient collectors of particulate with a dimension < 60-80 \u3bcm, and a simple and reliable procedure was developed to reveal traces of platinum, palladium and rhodium released from automotive catalysts. The analysis of the dust deposited on the foliage is a direct indicator of traffic pollution.
Materials and methods Leaves of prunus laurus cerasus were washed by sonication in a mixture of water and 2 propanol and the washings, to be discarded, were separated by centrifugation to yield typically 0.05-1.2 g of dust that, after mineralization, were directly submitted to Atomic Absorption analysis.
Results Comparison of the 2007 and 2004-5 results showed a dramatic reduction of the platinum levels and revealed that palladium is now the main component of this traffic related pollution.
Discussion The results are consistent with the increasing diffusion of cars with a diesel engine whose catalysts are made up of Pt and/or Pd alone, and gives a significant insight into the recent evolution in catalyst design that replaces platinum for palladium.
Conclusion The proposed analytical procedure is simple, with short preparation times, and greatly reduces matrix effects so that atomic absorption spectroscopy can easily detect the three noble metals at the ng/g level in the dust.
Recommendation and perspectives The results clearly show that Pd concentrations have increased over time, and must be cause of concern
Anomaly pre-localization in distribution–transmission mains by pump trip: preliminary field tests in the Milan pipe system
In this paper, the reliability of transients due to pump trip as a powerful tool for the pre-localization of anomalies in real pipe systems is tested. The examined pipe system is part of the one supplying the city of Milan, Italy and is managed by Metropolitana Milanese SpA (MM). The characteristics of such a system can be considered as intermediate between those of classical transmission mains and distribution systems because of its several branches. A Lagrangian model simulating pressure wave propagation is used to evaluate the pipe pressure wave speed – associated with a genetic algorithm – and to locate possible anomalies – associated with wavelet analysis. The results of the diagnosis of the pipe system are corroborated by repairs executed by MM in the area where possible anomalies have been pre-localized
The chemical evolution of Omega Centauri's progenitor system
Chemical evolution models are presented for the anomalous globular cluster
Omega Centauri. After demonstrating that the chemical features of Omega Cen can
not be reproduced in the framework of the closed-box self-enrichment scenario,
we discuss a model in which this cluster is the remnant of a dwarf spheroidal
galaxy evolved in isolation and then swallowed by the Milky Way. Both infall of
primordial matter and metal-enriched gas outflows have to be considered in
order to reproduce the stellar metallicity distribution function, the
age-metallicity relation and several abundance ratios. Yet, as long as an
ordinary stellar mass function and standard stellar yields are assumed, we fail
by far to get the enormous helium enhancement required to explain the blue main
sequence (and, perhaps, the extreme horizontal branch) stellar data. Rotating
models of massive stars producing stellar winds with large helium excesses at
low metallicities have been put forward as promising candidates to solve the
`helium enigma' of Omega Cen (Maeder & Meynet, 2006, A&A, 448, L37). However,
we show that for any reasonable choice of the initial mass function the
helium-to-metal enrichment of the integrated stellar population is unavoidably
much lower than 70 and conclude that the issue of the helium enhancement in
Omega Cen still waits for a satisfactory explanation. We briefly speculate upon
possible solutions.Comment: 11 pages, 9 figures; accepted for publication in MNRA
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