100 research outputs found
Countable and Uncountable in Group Theory
A prominent, recurring feature of group theory has been the determination of groups (all of) whose subgroups possess some group theoretical property. For infinite groups in a suitable universe a number of different approaches have been used in this regard. For locally finite groups, for example, knowledge of the structure of the finite subgroups is often crucial. On the other hand the concept of "largeness" has also recently played an interesting role. Moving from this, I started to study how subgroups of uncountable cardinality affect an uncountable group. Let X be a group theoretical proper, let G be a group of uncountable cardinality and suppose that all its proper uncountable subgroups satisfy X. Is it true that all (proper) subgroups of G satisfy X? The thesis exploits this question, showing that, under some soluble conditions, the answer is often positive. Finally the thesis deals with countably recognizable properties, which has a strong relation with the previous question
On derived-indecomposable solutions of the Yang--Baxter equation
If is a finite non-degenerate set-theoretic solution of the
Yang--Baxter equation, the additive group of the structure skew brace
is an -group, i.e. a group whose elements have finitely many conjugates.
Moreover, its multiplicative group is virtually abelian, so it is also close to
an -group itself. If one additionally assumes that the derived solution of
is indecomposable, then for every element of there are
finitely many elements of the form and , with . This
naturally leads to the study of a brace-theoretic analogue of the class of
-groups. For this class of skew braces, the fundamental results and their
connections with the solutions of the YBE are described: we prove that they
have good torsion and radical theories and they behave well with respect to
certain nilpotency concepts and finite generation.Comment: 24 pages. Accepted for publication in Publicacions Matem\`atique
Scenario analysis of pollutants loads to European regional seas for the year 2020. Part II: Assessment of priority chemicals ā an example with three pilot substances
In order to support the implementation of the Marine Strategy Framework Directive, DG Environment and the Joint Research Centre joined to carry out a study on the expected cumulative impact of existing EU environmental legislation on the quality of the marine environment, with specific reference to the case of aquatic discharges to the European seas.
The report describes a few scenario analyses affecting emissions to the European regional seas up to 2020 for Lindane, Trifluralin and Perfluorooctane sulfonate (PFOS) taken as pilot substances. The scenarios developed are agreed with stakeholders at DG ENV following some preparatory meetings. The scenarios do not intend be exhaustive, but examples of what can be further achieved making use of the modelling and database development made in the different phases of the project.
For Lindane, the model estimated European sea load of 745 tons per 1995, based on the official emission data provided by EMEP, appears to be reduced by 98.3% in 2005, ten years after the start of the EU regulations for Ī³-HCH. Besides, under the BAU scenario, a Lindane sea load of ca.12.5 tons per year should be expected. The trend and ban scenarios support, respectively, a reduction of the load to the European seas in 2020 by 74% and 95% when compared to the BAU estimate.
Aimed at Trifluralin, according to the BAU scenario, an annual load of ca.61.7 tones is estimated in 2020. However, this is an overestimation, because the aggregated emission data of EUROSTAT for the agriculture use of the entire group of dinitroaniline herbicides in for EU25 have been considered as model input data. The complete ban scenario forecasts ca. 0.07 t/y and in practice eliminates the concern about loads of Trifluralin to European seas to a negligible level in a time-frame of one year due to degradation in soil.
Considering PFOS under BAU scenario conditions the total sea load from all European contries is estimated to be 5.8 tons per year. The model forecasts approximately a half of this amount when a 50% reduction of emissions takes place.JRC.H.1-Water Resource
Assessment of Persistent Organic Pollutants load to marine environment by MAPPE-Global model focusing on European regional seas
MAPPE-Global modeling tool belongs to the group of the global box models for environmental fate and transport
of POPs. The estimated error level of MAPPE-Global is about a factor of two, which suggests that the model could be considered as a tool for a screening or initial evaluation of chemical risk for POPs at global scale.
The verified MAPPE-Global is applied in practical assessments of chemical loads to the European regional
seas. The PCBs case study relates to a sum of 22 congeners and considers two emission scenarios: first - the
current status relative to the 2010 year; second ā a future projection corresponding to the 2020 year. The total
amount of 22PCBs released to air equals to 101.03 t for year 2010 and to 50.2 t for year 2020, respectively. The
Baseline scenario for Lindane assumes, for the reference year 2005, 86.6 t atmospheric emissions only from
European sources and omits the impact of the long range atmospheric transport. The second scenario for
Lindane aims to targeting the situation in the year 2020. This scenario (denoted as LRT) suggests no emissions
to atmosphere from any European origin due to the banning of this substance but admits that Europe is affected
by an unavoidable āimportā of 5.4 t Lindane through trans-continental air transport.
According to the MAPPE-Global model, the extended European area is exporting to the marine water 3.7 t of
22PCBs in 2010 and 1.9 t in 2020, respectively. In both scenarios, the most affected seas are the Mediterranean Sea (ca.35%
from the total) followed by Northern (ca. 21.5%) and Black sea (ca. 19%). It was estimated that the European
seas receive by atmospheric deposition about 7.9 t of 22PCBs in 2010 and ca. 4t in 2020. This is two times
more when comparing to the entire riverine discharge of 22PCBs for these years.
MAPPE-Global forecasts 10.1 t riverine sea load of Lindane under the Baseline scenario and 0.26t in the case
of LRT meaning 97% reduction compared to the baseline option. The highest discharges are observed for Atlantic Ocean ā
in Baseline scenario 2.2t (21.8% from the total) and for LRT 0.06t (23%); and Mediterranean Sea - Baseline 3.5t
(34.7%) and LRT 0.04t (15.4%). For the gamma-HCH, likewise for the PCBs, it is found that the atmospheric
deposition over the European seas dominate the river input to the coastal zone. Under the Baseline scenario,
the total air deposition (50.2t/y) is about 5 times higher than the riverine component of the sea load.
Potentially the outcome of MAPPE-Global model could serve in the assessments of different policy options
related to the EU Water Framework Directive (WFD) or Marine Strategy Framework Directive (MSFD) as well as
to support the implementation of the European sea conventions as HELCOM (Baltic Sea), OSPAR (North-East
Atlantic), MEDPOL (Mediterranean Sea) and BSC (Black Sea).JRC.H.1-Water Resource
Methods for Regional Integrated Assessment: High resolution gridded emission distribution in the LUISA Platform
This report illustrates the progresses made towards the inclusion of air quality related issues in the Land Use-based Integrated Sustainability Assessment (LUISA) platform. It focuses on the description of the methodology to derive high-resolution gridded-emission spatially geo-referenced layers from outputs and datasets integrated in LUISA.
In the framework of the integration of the Regional Integrated Assessment Tool (RIAT model) and the Land Use Modelling Integrated Sustainability Assessment (LUISA) platform, we implemented the downscaling of atmospheric emission data from national level to very high spatial resolution (100m). The GAINS model (IIASA) provides the input emission data for different scenarios, up to year 2030, which are disaggregated based on 34 different surrogates. Each surrogate is calculated by means of the integration of several proxies derived by statistical datasets, ancillary models and GIS layers in the framework of the LUISA platform. The preliminary results for NOx, PM10 and NH3 (year 2010) are presented in this report together with their first assessment, based on existing emission maps at 7 and 10 Km resolution. Future steps for further refinements are also discussed.JRC.H.8-Sustainability Assessmen
Multimedia assessment of pollutant pathways in the environment: a Global scale model
The report describes the assumptions, equations and a few examples of preliminary applications of a global spatial steady-state box model entitled Multimedia Assessment of Pollutant Pathways in the Environment (MAPPE-Global). The model grounds on the concept of already developed European version of MAPPE chemical fate model.
MAPPE-Global computes the removal rates of a substance with given physical-chemical properties in an evaluative environment for the Globe with a resolution of 1x1 degree considering atmosphere, land (natural and agriculture soils, forests, impervious surfaces, frozen territories), surface water (including lakes, inland wetlands and reservoirs) and oceans and seas.
MAPPE-Global is able to consider chemical emissions in one or more of the environmental compartments and estimates chemical concentrations and fluxes accounting chemical partitioning (gas, liquid or solid), degradation, advective and diffusive transport.
At this stage, MAPPE Global does not explicitly compute chemical transport in space, but only the fate of a substance at each location in space. However, the model estimates for each grid cell the mass fluxes of chemical that are available for transport inside or outside of the cell, in addition to concentrations from local emissions. Thus, MAPPE Global is developed specifically to respond questions as:
ā¢ How will a chemical spread across different media in the different climatic and landscape settings?
ā¢ How important is the variability of environmental processes in determining the fate of chemicals across the globe?
In addition, the model enables estimating, for virtually any location in the world, representative parameters of the environmental removal rates that determine the fate of a contaminant. These rates may be used to feed a zero-dimensional time-dependent model that allows computing the main receptors of the chemical emissions.
Besides, in order to evaluate the performance of the MAPPE-Global model a comparison with established models, such as Impact World and USEtox was made by crosschecking of the intermedia removal rate coefficients.
Finally, MAPPE-Global was used to quantify for a set of 34 representative pollutants at global scale the range of variability of chemical removal rates for the different environmental compartments and to identify the fate patterns of flyers, swimmers, soil-bound and multimedia chemical substances.JRC.H.5-Rural, water and ecosystem resource
Central nilpotency of left skew braces and solutions of the Yang-Baxter equation
Nipotency of skew braces is related to certain types of solutions of the
Yang-Baxter equation. This paper delves into the study of centrally nilpotent
skew braces. In particular, we study their torsion theory (Section 4.1) and we
introduce an "index" for subbraces (Section 4.2), but we also show that the
product of centrally nilpotent ideals need not be centrally nilpotent (Example
B), a rather peculiar fact. To cope with these examples, we introduce a special
type of nilpotent ideal, using which, we define a {\it good} Fitting ideal.
Also, a Frattini ideal is defined and its relationship with the Fitting ideal
is investigated.
A key ingredient in our work is the characterisation of the commutator of
ideals in terms of absorbing polynomials (Section 3); this solves Problem 3.4
of arXiv:2109.04389. Moreover, we provide an example (Example A) showing that
the idealiser of a subbrace (as defined in arXiv:2205.01572v2) does not exist
in general.Comment: 44 pages, definition of centralizer is modifie
A History of Group Theory through the Lives of Group Theorists: Sophus Lie - Part 1
We continue here our attempt of a systematic historical account of Group Theory inspected by means of the lives and the works of its main actors. The aim is to bring the interested reader through orig- inal correspondences, published and unpublished works, historical perspectives, diatribes and friendships.
This issue contains the translation of a memory of Sophus Lie writ- ten by Ludwig Sylow. It was published in the 1899 issue of Archiv for Mathematik of Naturvidenskab soon after Lieās death.
We are grateful to Gunnar Traustason for his translation from Nor- wegian
Regional patterns of energy production and consumption factors in Europe Exploratory Project EREBILAND - European Regional Energy Balance and Innovation Landscape
The Resilient Energy Union with Forward Looking Climate Change Policy is one the ten priorities of the overarching Agenda for Jobs, Growth, Fairness and Democratic Change of the European Commission. The Communication on the Energy Union package and its Annex clearly identify EU-wide targets and policy objectives.
The Exploratory Project EREBILAND (European Regional Energy Balance and Innovation Landscape) aims at supporting efficient patterns of regional energy supply and demand in Europe. Integration of spatial scales, from EU-wide to regional or local, and a cross-sector approach, are at the core of the project.
The approach is based on territorial disaggregation of information, and the development of optimisation scenarios at regional scale. It is centred around the Land Use-based Integrated Sustainability Assessment (LUISA) modelling platform for the assessment of policies and investments that have spatial impacts, in interaction with the JRC-EU-TIMES model ā a bottom-up, technology-rich model representing the EU28+ energy system ā and the model RHOMOLO that integrates economic and some social dimensions of regional development.
Based on currently operational and up-to-date tools available within the EC, the purpose of the EREBILAND project is to:
ā¢ provide an overview of the current trends of regional energy production and consumption patterns, and
ā¢ link these patterns to the structural characteristics of the regions, among which: population density and urbanisation trends, development of different economic sectors, and availability of resources and technological infrastructure.
This report presents the outcomes of the EREBILAND Project during its first year.
In particular, electricity generation and energy consumed by transport sector are analysed, under the EU Energy Reference Scenario 2013, throughout the period 2015 - 2030.
Main results of the analysis dedicated to the electricity generation are:
ā¢ Electricity generation from biomass increases in the large majority of European regions; a slight decrease can be found only in regions producing electricity already in 2015 above the EU28 average (in Denmark).
ā¢ Electricity produced from biogas experiences less steep changes then biomass, with almost 50% of NUTS2 decreasing or not changing considerably the amount of electricity produced from this source.
ā¢ Coal: electricity generated from lignite undergoes a significant reduction in all regions using this fuel already in 2015. Conversely, trends in electricity generated from hard coal are more stable, with some regions experiencing an increase: the average change is higher than 50% (a few regions in Eastern European countries), but steeper increases can be found in Austria, Sweden and the United Kingdom.
ā¢ The amount of electricity generated from gas generally decreases across Europe from 2015 to 2030, with an average decrease higher than 90%.
ā¢ Geothermal is the least diffuse source used to generate electricity in Europe and only few regions are represented.
ā¢ Hydroelectric: the amount of electricity generated from this source is in general forecasted to increase in Europe from 2015 to 2030. Exceptions are a few regions in Bulgaria, Czech Republic, Germany, Spain, Greece, Hungary, Portugal, Romania, Sweden and most NUTS2 in the UK.
ā¢ Electricity generated from nuclear is forecasted to decrease in the majority of the regions with active nuclear power plants in 2015.
ā¢ Oil: the majority of the regions generating electricity from this fuel in 2015, experience a decrease in 2030. Notable exceptions are a few regions in Austria, Belgium, Germany, Greece, Hungary, Italy, Poland and Slovenia.
ā¢ Electricity produced from solar is forecasted to increase in almost three quarters of European regions. The only regions where electricity from solar is forecasted to decrease are located in Greece and Romania.
ā¢ Wind: electricity generated from wind, both on- and off-shore, is in general forecasted to increase in Europe. The largest increases in electricity generated from on-shore wind (above 5 times the 2015 generation levels) can be found in few regions in Czech Republic, Finland, Lubuskie in Poland, the north-est NUTS2 in Romania, Western Slovakia and Slovenia.
Main results of the analysis dedicated to energy consumption of the transport sector are:
ā¢ In more than two thirds of European regions, the energy supplied to cars (fuel: diesel) decreases from 2015 to 2030, with an average decrease of almost 20%.
ā¢ The energy supplied to cars (fuels: gas and LPG) is forecasted to decrease throughout all European regions. The decrease is more gradual in few regions in Denmark, Portugal, Greece, Spain and Italy.
ā¢ Energy supplied to cars (fuel: gasoline) is forecasted to decrease in more than 80% of the European regions, with an average decrease of 27%.
ā¢ The energy supplied to heavy duty trucks (fuel: diesel) is forecasted to progressively decrease from 2015 to 2030 in 66% of the European regions, with an average decrease of more than 8%.
ā¢ The energy supplied to light duty trucks (fuel: diesel) is forecasted to steeply decrease throughout European regions.
ā¢ The energy supplied to light duty trucks (fuel: gasoline) is forecasted to increase in more than 90% of European regions, with an average increase of more than 40% from 2015 to 2030. The highest increases (above 70%) take place in eleven regions in Germany, Walloon Brabant in Belgium, Flevoland in the Netherlands, Lower Austria and Eastern Macedonia and Thrace.
ā¢ The energy supplied to inter-city buses running on diesel is forecasted to increase from 2015 to 2030 in the large majority of European regions, with an average increase of more than 19%.
ā¢ The energy supplied to urban buses (fuels: gas, diesel and gasoline) is going to moderately increase from 2015 to 2030 in almost 90% regions throughout EU-28, with an average growth of 15%.
ā¢ Energy supplied to motorcycles (fuel: gasoline) is forecasted to increase in more than 80% of European NUTS2, with an average growth of 16%.
ā¢ Energy supplied to cars (fuels: hybrid, electric and hydrogen) is forecasted to increase throughout Europe, in general with sharp increases.
ā¢ Energy supplied to heavy duty trucks (fuel: gas) and light duty trucks (fuel: LPG) is forecasted to increase in all European regions from 2015 to 2020. In most NUTS2 this trend is kept or even accelerates between 2020 and 2030. The only regions where the trend is reversed (lower energy supplied in 2030 compared to 2020) are located in Poland, Greece, Finland (only Ć
land) and Croatia (only Jadranska Hrvatska).JRC.H.8-Sustainability Assessmen
In vivo and in vitro effects of selected antioxidants on rabbit meat microbiota
The purpose of this study was to investigate the effect of dietary vitamin E or EconomasEā¢ supplementation on the growth of several background/pathogenic bacteria on rabbit carcasses and hamburgers during refrigerated storage. For 51days, 270 New Zealand rabbits received either a basal diet, or experimental diets enriched with 100 or 200mg/kg of vitamin E or EconomasEā¢. The bacteria studied were Salmonella, Listeria monocytogenes, Pseudomonas, Enterobacteriaceae, Escherichia coli, coagulase-positive staphylococci, plus both mesophilic and psychrotrophic aerobes. The growth of Listeria monocytogenes on contaminated patties was evaluated through a challenge test. The potential protective or antimicrobial effect of vitamin E or EconomasEā¢ on Listeria monocytogenes or Pseudomonas aeruginosa was assessed in vitro. Diet did not influence the concentrations of bacteria found on rabbit carcasses and developing on hamburgers. Vitamin E (in vivo and in vitro) and EconomasEā¢ in vivo had a protective antioxidant role, while EconomasEā¢ in vitro had strong antibacterial activity against Listeria monocytogenes, but not against Pseudomonas aeruginosa
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