840 research outputs found
The value of traditional rural landscape and nature protected areas in tourism demand: A study on agritourists' preferences
This study focuses on how traditional rural landscape and proximity to a Natura 2000 Site of Community Importance (SCI) might influence consumers\u2019 choice of an agritourism farm for a weekend stay. Data were collected in Umbria region\u2019s (Italy) agritourism farms in 2014 by interviewing 160 tourists. Results from a discrete choice experiment reveal that the most important feature affecting the interviewees\u2019 propensity to pay a premium price to stay in an agritourism farm is the well-preserved traditional landscape (willingness to pay 32.32\u20ac/night for two people), followed by the availability of a swimming pool (willingness to pay 20.95\u20ac/night for two people), the proximity to a historical village (willingness to pay 18.37\u20ac/night for two people) and, the location in a Natura 2000 SCI (willingness to pay 13.57\u20ac/night for two people). Furthermore, the results underline how the preservation of the traditional landscape and protection of the surrounding environment play a strategic role in developing agritourism and provide economic benefits to local communities
Lagrangian Formalism for nonlinear second-order Riccati Systems: one-dimensional Integrability and two-dimensional Superintegrability
The existence of a Lagrangian description for the second-order Riccati
equation is analyzed and the results are applied to the study of two different
nonlinear systems both related with the generalized Riccati equation. The
Lagrangians are nonnatural and the forces are not derivable from a potential.
The constant value of a preserved energy function can be used as an
appropriate parameter for characterizing the behaviour of the solutions of
these two systems. In the second part the existence of two--dimensional
versions endowed with superintegrability is proved. The explicit expressions of
the additional integrals are obtained in both cases. Finally it is proved that
the orbits of the second system, that represents a nonlinear oscillator, can be
considered as nonlinear Lissajous figuresComment: 25 pages, 7 figure
Consumers demand for social farming products: An analysis with discrete choice experiments
This paper analyses the demand for social farming (SF) products. In particular, we investigate the preferences of consumers who buy their products from large retailers, rather than from solidarity purchasing groups or other niche markets using a sample of 225 consumers. In this regard, a discrete choice experiment (DCE) was carried out to estimate the willingness to pay (WTP) a premium price for the purchase of a common product (i.e., eggs) from farms that employ disabled people. The attributes considered in our DCE design are the employment of disabled people and two additional attributes which may have ethical implications for the choices. The results indicate that consumers are interested in buying SF products, with about 74% of the sample willing to buy the eggs produced by social farms and the average WTP being equal to \u20ac1.36 for a pack of six eggs. Moreover, the average WTP for the use of labour of disabled people attribute amounted to \u20ac0.69 for a pack of six eggs
The Integrability of Pauli System in Lorentz Violating Background
We systematically analyze the integrability of a Pauli system in Lorentz
violating background at the non-relativistic level both in two- and
three-dimensions. We consider the non-relativistic limit of the Dirac equation
from the QED sector of the so-called Standard Model Extension by keeping only
two types of background couplings, the vector a_mu and the axial vector b_mu.
We show that the spin-orbit interaction comes as a higher order correction in
the non-relativistic limit of the Dirac equation. Such an interaction allows
the inclusion of spin degree non-trivially, and if Lorentz violating terms are
allowed, they might be comparable under special circumstances. By including all
possible first-order derivative terms and considering the cases a\ne 0, b\ne 0,
and b_0\ne 0 one at a time, we determine the possible forms of constants of
motion operator, and discuss the existence or continuity of integrability due
to Lorentz violating background.Comment: 19 page
Group entropies, correlation laws and zeta functions
The notion of group entropy is proposed. It enables to unify and generalize
many different definitions of entropy known in the literature, as those of
Boltzmann-Gibbs, Tsallis, Abe and Kaniadakis. Other new entropic functionals
are presented, related to nontrivial correlation laws characterizing
universality classes of systems out of equilibrium, when the dynamics is weakly
chaotic. The associated thermostatistics are discussed. The mathematical
structure underlying our construction is that of formal group theory, which
provides the general structure of the correlations among particles and dictates
the associated entropic functionals. As an example of application, the role of
group entropies in information theory is illustrated and generalizations of the
Kullback-Leibler divergence are proposed. A new connection between statistical
mechanics and zeta functions is established. In particular, Tsallis entropy is
related to the classical Riemann zeta function.Comment: to appear in Physical Review
Depressive-like behavior is paired to monoaminergic alteration in a murine model of Alzheimer's disease
Background: Neuropsychiatric signs are critical in primary caregiving of Alzheimer patients and have not yet been fully investigated in murine models. Methods: 18-month-old 3.Tg-AD Male mice and their wild-type Male littermates (non-Tg) were used. The open field test and the elevated plus maze test were used to evaluate anxiety-like behaviors, whereas the Porsolt forced swim test, the tail suspension test, and the sucrose preference test for antidepressant/depression-coping behaviors. Neurochemical study was conducted by microdialysis in freely-moving mice, analyzing the basal and K+-stimulated monoamine output in the frontal cortex and ventral hippocampus. Moreover by immunohistochemistry, we analysed the expression of Tyrosin hydroxylase and Tryptophan hydroxylase, which play a key role in the synthesis of monoamines. Results: Aged 3.Tg-AD mice exhibited a higher duration of immobility in the forced swim and tail suspension tests (predictors of depression-like behavior) which was not attenuated by a noradrenaline reuptake inhibitor, desipramine. In the sucrose preference test, 3.Tg-AD mice showed a significantly lower sucrose preference compared to the non-Tg group, without any difference in total fluid intake. In contrast, the motor functions and anxiety-related emotional responses of 3.Tg-AD mice were normal, as detected by the open-field and elevated plus-maze tests. To strengthen these results, we then evaluated the monoaminergic neurotransmissions by in vivo microdialysis and immunohistochemistry. In particular, with the exception of the basal hippocampal dopamine levels, 3.Tg-AD mice exhibited a lower basal extracellular output of amines in the frontal cortex and ventral hippocampus and also a decreased extracellular response to K+ stimulation. Such alterations occur with obvious local amyloid-β and tau pathologies and without gross alterations in the expression of Tyrosin and Tryptophan hydroxylase. Conclusions: These results suggest that 3.Tg-AD mice exhibit changes in depression-related behavior involving aminergic neurotrasmitters and provide an animal model for investigating AD with depression
Fe-rich ferropericlase and magnesiow\ufcstite inclusions reflecting diamond formation rather than ambient mantle
At the core of many Earth-scale processes is the question of what the deep mantle is made of. The only direct samples from such extreme depths are diamonds and their inclusions. It is commonly assumed that these inclusions reflect ambient mantle or are syngenetic with diamond, but these assumptions are rarely tested. We have studied inclusion\u2013host growth relationships in two potentially superdeep diamonds from Juina (Brazil) containing nine inclusions of Fe-rich (XFe 480.33 to 650.64) ferropericlase-magnesiow\ufcstite (FM) by X-ray diffractometry, X-ray tomography, cathodoluminescence, electron backscatter diffraction, and electron microprobe analysis. The inclusions share a common [112] zone axis with their diamonds and have their major crystallographic axes within 3\ub0\u20138\ub0 of those of their hosts. This suggests a specific crystallographic orientation relationship (COR) resulting from interfacial energy minimization, disturbed by minor post-entrapment rotation around [112] due to plastic deformation. The observed COR and the relationships between inclusions and diamond growth zones imply that FM nucleated during the growth history of the diamond. Therefore, these inclusions may not provide direct information on the ambient mantle prior to diamond formation. Consequently, a \u201cnon-pyrolitic\u201d composition of the lower mantle is not required to explain the occurrence of Fe-rich FM inclusions in diamonds. By identifying examples of mineral inclusions that reflect the local environment of diamond formation and not ambient mantle, we provide both a cautionary tale and a means to test diamond-inclusion time relationships for proper application of inclusion studies to whole-mantle questions
Lorentz and Galilei Invariance on Lattices
We show that the algebraic aspects of Lie symmetries and generalized
symmetries in nonrelativistic and relativistic quantum mechanics can be
preserved in linear lattice theories. The mathematical tool for symmetry
preserving discretizations on regular lattices is the umbral calculus.Comment: 5 page
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