474 research outputs found
Anàlisi dels aspectes socials de la caça a Mallorca: distribució territorial, anàlisi per edats i gèneres, tipologies de llicències i comparatives
[cat] L’activitat cinegètica constitueix un dels principals moviments que vertebren el medi rural de les Illes Balears. A partir de la informació facilitada pel Servei de Caça del Consell de Mallorca s’avalua el ressò social del col·lectiu venatori, indicador bàsic per determinar qüestions relaciones amb el potencial de gestió dels espais cinegètics o per avaluar l’impacte econòmic de l’activitat, entre d’altres. S'analitza la distribució, l'edat, el gènere i les modalitats que practiquen les persones titulars de llicències de caça a Mallorca. En un marc socioeconòmic hipertrofitzat pel sector terciari i territorialment limitat, s'observa com la caça persisteix amb força a la majoria de municipis amb emergència de les pràctiques tradicionals i el turisme cinegètic. La manca de relleu generacional, els efectes de la crisi econòmica i la introgressió d’usos urbans són alguns dels factors limitants. Així mateix, la variable gènere marca diferències essencials entre la caça i altres activitats de lleure atesa l’escassa presència de la dona.[eng] The hunting activity is one of the main movements that structure the rural environment of the Balearic Islands. From the information provided by the Hunting Service of the Mallorcan Council the following are assessed among others: the social impact of the hunting collective, basic indicator to determine potential issues related to the management of hunting areas or to evaluate the economic impact of the activity. It analyzes the distribution, age, gender and types of people who practice hunting license holders of Mallorca. A geographically limited framework with a socioeconomical environment based on the tertiary sector, shows how hunting strongly persists in most municipalities with emergence of practices traditional hunting and cynegetic tourism. The lack of generational change, the effects of the economic crisis and the introgression of urban uses are some of the limiting factors. Also, gender marks an essential difference between hunting and other recreational activities given the limited presence of women
Magnetocaloric Effect Caused by Paramagnetic Austenite–Ferromagnetic Martensite Phase Transformation
In the present work, the magnetization of Ni50Mn17.5Ga25Cu7.5 alloy undergoing the first-order phase transition from paramagnetic austenite to ferromagnetic martensite was measured to evaluate the magnetic-field-induced entropy change (MFIEC) and refrigerant capacity (RC) of the alloy. A standard method (SM) of evaluation of MFIEC is based on thermodynamic Maxwell relation. In view of the criticism of SM expressed by some scientists, the alternative method (AM), which is based on thermodynamic relationships for free energy, was proposed recently for the determination of MFIEC. We developed this method and computed MFIEC in two ways—by AM and SM. The values of MFIEC obtained for Ni50Mn17.5Ga25Cu7.5 alloy by these methods appeared to be large but very different from each other. Moreover, AM reveals the possibility of both normal and inverse magnetocaloric effects in the adjoining temperature ranges, while SM results only in the normal magnetocaloric effect.This research was funded by AEI/FEDER, UE (projects MAT2014-56116-C04-01-R and MAT2012-
37923-C02-01), NASU (project 0117U000433), MESU (project 0117U004340) and SFFR (President’s of Ukraine grant
F75/156-2018)
Encoding the scaling of the cosmological variables with the Euler Beta function
We study the scaling exponents for the expanding isotropic flat cosmological
models. The dimension of space, the equation of state of the cosmic fluid and
the scaling exponent for a physical variable are related by the Euler Beta
function that controls the singular behavior of the global integrals. We
encounter dual cosmological scenarios using the properties of the Beta
function. For the entropy density integral we reproduce the Fischler-Susskind
holographic bound.Comment: Latex2e, 11 pages, 1 figure; reference added; minor changes
commenting the nature of the holographic principle and the particle/event
horizo
Monogenic Diabetes Modeling: In Vitro Pancreatic Differentiation From Human Pluripotent Stem Cells Gains Momentum.
The occurrence of diabetes mellitus is characterized by pancreatic β cell loss and chronic hyperglycemia. While Type 1 and Type 2 diabetes are the most common types, rarer forms involve mutations affecting a single gene. This characteristic has made monogenic diabetes an interesting disease group to model in vitro using human pluripotent stem cells (hPSCs). By altering the genotype of the original hPSCs or by deriving human induced pluripotent stem cells (hiPSCs) from patients with monogenic diabetes, changes in the outcome of the in vitro differentiation protocol can be analyzed in detail to infer the regulatory mechanisms affected by the disease-associated genes. This approach has been so far applied to a diversity of genes/diseases and uncovered new mechanisms. The focus of the present review is to discuss the latest findings obtained by modeling monogenic diabetes using hPSC-derived pancreatic cells generated in vitro. We will specifically focus on the interpretation of these studies, the advantages and limitations of the models used, and the future perspectives for improvement
A comparative study on renewable and traditional electricity: The influence of the European Union framework and the impact of COVID-19
By means of the event study approach, we analyse the effect of COVID-19 on listed European renewable and traditional electricity companies, inside and outside the European Union, for the pandemic announcement and lockdowns. We find that the pandemic negatively affected both subsectors of electricity production, but the negative effect was more intense for renewable electricity companies, since they represent a riskier investment. Moreover, this negative effect was larger for European electricity companies than for companies from countries that do not belong to the European Union. Our results show the riskier profile of the clean energy industry together with the importance of a stable and supportive regulatory framework to develop and consolidate renewable energy. Our findings have important implications for policymakers. In addition to the intrinsic risks associated with renewable energy, this type of investment poses policy and regulatory risks, which they should take into account when evaluating future energy policies. Policymakers must be aware of the importance of these specific risks, and seek to respond to investors' expectations about long-term, stable regulations
Radiopurity of Micromegas readout planes
Micromesh Gas Amplification Structures (Micromegas) are being used in an
increasing number of Particle Physics applications since their conception
fourteen years ago. More recently, they are being used or considered as readout
of Time Projection Chambers (TPCs) in the field of Rare Event searches (dealing
with dark matter, axions or double beta decay). In these experiments, the
radiopurity of the detector components and surrounding materials is measured
and finely controlled in order to keep the experimental background as low as
possible. In the present paper, the first measurement of the radiopurity of
Micromegas planes obtained by high purity germanium spectrometry in the low
background facilities of the Canfranc Underground Laboratory (LSC) is
presented. The obtained results prove that Micromegas readouts of the microbulk
type are currently manufactured with radiopurity levels below 30 microBq/cm2
for Th and U chains and ~60 microBq/cm2 for 40K, already comparable to the
cleanest detector components of the most stringent low background experiments
at present. Taking into account that the studied readouts were manufactured
without any specific control of the radiopurity, it should be possible to
improve these levels after dedicated development.Comment: 15 pages, 2 figure
Exploring a simple sector of the Einstein-Maxwell landscape
We explore the four dimensional Einstein-Maxwell landscape as a toy model in
which we can formulate a sphere compactification stabilized by an
electromagnetic field. Replacing the compactification sphere by J spheres, we
obtain a simple sector of the (2J+2)-dimensional Einstein-Maxwell landscape. In
this toy model, we analyze some properties which are very difficult to uncover
in the string theory landscape, including: complete moduli stabilization,
stability conditions, and state counting. We also show how to construct
anthropic states in this model. A detailed comparison between the main features
of this landscape and the Bousso-Polchinski landscape is given. We finally
speculate on the impact of these phenomena in the string theory landscape.Comment: 69 pages, 16 figures, some references adde
Spectroscopy and large scale wave functions
We discuss the relevance of long wavelength excitations for the low energy spectrum of QCD, and try to develop an efficient method for solving the Schrodinger equation, and for extracting the glueball masses and long wavelength functions of the ground and excited states. Some technical problems appearing in the calculations of SU(3) gauge theory are discussed
Gaseous time projection chambers for rare event detection: Results from the T-REX project. II. Dark matter
As part of the T-REX project, a number of R&D and prototyping activities have
been carried out during the last years to explore the applicability of
Micromegas-read gaseous TPCs in rare event searches like double beta decay
(DBD), axion research and low-mass WIMP searches. While in the companion paper
we focus on DBD, in this paper we focus on the results regarding the search for
dark matter candidates, both axions and WIMPs. Small ultra-low background
Micromegas detectors are used to image the x-ray signal expected in axion
helioscopes like CAST at CERN. Background levels as low as
c keVcms have already been achieved in CAST while values
down to c keVcms have been obtained in a
test bench placed underground in the Laboratorio Subterr\'aneo de Canfranc.
Prospects to consolidate and further reduce these values down to
c keVcmswill be described. Such detectors, placed at the
focal point of x-ray telescopes in the future IAXO experiment, would allow for
10 better signal-to-noise ratio than CAST, and search for solar axions with
down to few 10 GeV, well into unexplored axion
parameter space. In addition, a scaled-up version of these TPCs, properly
shielded and placed underground, can be competitive in the search for low-mass
WIMPs. The TREX-DM prototype, with 0.300 kg of Ar at 10 bar, or
alternatively 0.160 kg of Ne at 10 bar, and energy threshold well below 1
keV, has been built to test this concept. We will describe the main technical
solutions developed, as well as the results from the commissioning phase on
surface. The anticipated sensitivity of this technique might reach
cm for low mass ( GeV) WIMPs, well beyond current
experimental limits in this mass range.Comment: Published in JCAP. New version with erratum incorporated (new figure
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