566 research outputs found
Territorial pressure and tourism contribution to GDP: The case of Italian regions
This article focuses on long-run co-movement between tourists' arrivals and per capita income with the aim of evaluating, through a macroeconomic perspective, whether its excessive increase can be detrimental to economic development. To this aim, GDP per capita in Italian NUTS2 regions is connected, through a dynamic panel cointegrating technique, to arrivals and to a measure of touristic congestion (tourism territorial pressure index). Results show that tourism contributes to the increase of
per capita GDP. However, when accounting for the congestion effect, the relation appears to be nonlinear, revealing a detrimental effect on growth driven by an excessive tourism pressure on territories
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STILTool: a Semantic Table Interpretation evaLuation Tool
This paper describes STILTool, an open-source tool for the automatic evaluation of the quality of semantic annotations computed by semantic table interpretation approaches. STILTool provides a graphical interface allowing users to analyse the correctness of the annotations of tabular data. The tool also provides a set of statistics in order to identify the most common error patterns
External voltage sources and Tunneling in quantum wires
We (re) consider in this paper the problem of tunneling through an impurity
in a quantum wire with arbitrary Luttinger interaction parameter. By combining
the integrable approach developed in the case of Quantum Hall edge states with
the introduction of radiative boundary conditions to describe the adiabatic
coupling to reservoirs, we are able to obtain the exact equilibrium and non
equilibrium current. One of the most striking features observed is the
appearance of negative differential conductances out of equilibrium in the
strongly interacting regime g <=.2. In spite of the various charging effects, a
remarkable form of duality is still observed.
New results on the computation of transport properties in integrable impurity
problems are gathered in appendices. In particular, we prove that the TBA
results satisfy a remarkable relation, originally derived using the Keldysh
formalism, between the order T^2 correction to the current out of equilibrium
and the second derivative of this current at T=0 with respect to the voltage.Comment: 16 pages, 7 figure
An Improved UFLS Scheme based on Estimated Minimum Frequency and Power Deficit
In the event of a power system disturbance, it is important that the decision to implement under frequency load shedding is based on both the minimum frequency and the magnitude of the disturbance. In this paper, we propose the use of higher order polynomial curve fitting to estimate the minimum frequency. If the prediction shows that the minimum frequency threshold will be violated, the magnitude of the total disturbance is estimated using the swing equation. In addition, the minimum amount of load that must be shed to restore the frequency just above the minimum value can also be directly calculated. Simulations are carried out for the considered Taiwan power system and the results prove the efficiency of the proposed technique
Fine-needle cytology in the follow-up of breast carcinoma
The postoperative follow-up strategies for breast carcinoma (BC) utilize different procedures; the aim of this study was to investigate the role of fine-needle cytology (FNC) in the follow-up of BC patients. Two hundred sixty-six FNC samples from 190 BC patients have been reviewed. The target anatomical sites were 190 breast including 155 ipsilateral and 145 contralateral breast lesions and 76 extra-mammary nodules. Extra-mammary lesions included lymph nodes, thyroidal nodules, soft tissue lesions, (subcutaneous and sub-scars), salivary glands and deep located masses. Diagnostic distribution of the breast lesions was as follows: 51 positive, 15 indeterminate/suspicious, 119 negative and 5 inadequate. Positive cases included 43 ipsilateral and 8 contralateral BC, 9 BC in different quadrants from those of onset of the first BC. Sensitivity, specificity and accuracy have been 90, 91 and 90&, respectively. FNC, in a correct setting, is a reliable and effective method for the follow-up management of BC patients
Current bistability and hysteresis in strongly correlated quantum wires
Nonequilibrium transport properties are determined exactly for an
adiabatically connected single channel quantum wire containing one impurity.
Employing the Luttinger liquid model with interaction parameter , for very
strong interactions g\lapx 0.2, and sufficiently low temperatures, we find an
S-shaped current-voltage relation. The unstable branch with negative
differential conductance gives rise to current oscillations and hysteretic
effects. These non perturbative and non linear features appear only out of
equilibrium.Comment: 4 pages, 1 figur
Transport theory of carbon nanotube Y junctions
We describe a generalization of Landauer-B\"uttiker theory for networks of
interacting metallic carbon nanotubes. We start with symmetric starlike
junctions and then extend our approach to asymmetric systems. While the
symmetric case is solved in closed form, the asymmetric situation is treated by
a mix of perturbative and non-perturbative methods. For N>2 repulsively
interacting nanotubes, the only stable fixed point of the symmetric system
corresponds to an isolated node. Detailed results for both symmetric and
asymmetric systems are shown for N=3, corresponding to carbon nanotube Y
junctions.Comment: submitted to New Journal of Physics, Focus Issue on Carbon Nanotubes,
15 pages, 3 figure
Immunometabolism Modulation by Extracts from Pistachio Stalks Formulated in Phospholipid Vesicles
Several studies have demonstrated the effectiveness of plant extracts against various diseases, especially skin disorders; namely, they exhibit overall protective effects. The Pistachio (Pistacia vera L.) is known for having bioactive compounds that can effectively contribute to a person’s healthy status. However, these benefits may be limited by the toxicity and low bioavailability often inherent in bioactive compounds. To overcome these problems, delivery systems, such as phospholipid vesicles, can be employed. In this study, an essential oil and a hydrolate were produced from P. vera stalks, which are usually discarded as waste. The extracts were characterized by liquid and gas chromatography coupled with mass spectrometry and formulated in phospholipid vesicles intended for skin application. Liposomes and transfersomes showed small size (<100 nm), negative charge (approximately −15 mV), and a longer storage stability for the latter. The entrapment efficiency was determined via the quantification of the major compounds identified in the extracts and was >80%. The immune-modulating activity of the extracts was assayed in macrophage cell cultures. Most interestingly, the formulation in transfersomes abolished the cytotoxicity of the essential oil while increasing its ability to inhibit inflammatory mediators via the immunometabolic citrate pathway
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