7,410 research outputs found
Optical emission investigation of laser-produced MgB2 plume expanding in an Ar buffer gas
Optical emission spectroscopy is used to study the dynamics of the plasma
generated by pulsed-laser irradiation of a MgB2 target, both in vacuum and at
different Ar buffer gas pressures. The analysis of the time-resolved emission
of selected species shows that the Ar background gas strongly influences the
plasma dynamics. Above a fixed pressure, plasma propagation into Ar leads to
the formation of blast waves causing both a considerable increase of the
fraction of excited Mg atoms and a simultaneous reduction of their kinetic flux
energy. These results can be particularly useful for optimizing MgB2 thin film
deposition processes.Comment: 11 pages,4 figures, Applied Physics Letters in pres
A Producer's Propensity to Conserve Framework: Application to a US and Australian Conservation Program
Increasing recognition of the environmental impact of agriculture has led to increasing public activity around the world encouraging public conservation programs. Different countries have taken different program approaches to accomplish this. The comparison and contrast here is between Australia and the United States, examining the CREP program in the U.S. and the Eco Tender program in Australia. A different historical experience in the U.S. sets certain parameters that are expected in their conservation programs. To some extent, the Australian program could take more of a clean slate approach. The Australian program is able to take a broader landscape approach, specifically considering multiple benefits with knowledge about off-site benefits as well. This is tied into a structured auction process that does not allow gaming of the auction process. While the U.S. approach does include a bidding process, its structure is such that it has characteristics of an incentive program. The U.S. approach also gives less incentive to farmers to provide environmental amenities at the lowest possible cost. Taking off-site impacts into consideration and finding ways to induce competition among farmers to provide amenities at the lowest cost to the public are seen as important characteristics of cost effective conservation programs.Resource /Energy Economics and Policy,
The Lira’s purchasing power from Italy’s unification to the single European Currency
This article analyses the behaviour of several price indexes over the whole life
of the Italian lira (1861-1998), and for various sub-periods defined by the
exchange-rate regimes of the Italian monetary history. We focus on the
persistence and stationarity properties of the inflation process and their
dependence on the real cycle. An international comparison with the United
States and the United Kingdom further supports the conclusion that Italian
inflation was abnormal as far as its mean value, degree of persistence and
relationship to the real cycle are concerned. In particular, we find that the
output-inflation relationship had a textbook-like, positive slope only during
periods of low inflation and low production volatility
Stress in Context: Morpho-Syntactic Properties Affect Lexical Stress Assignment in Reading Aloud
Recent findings from English and Russian have shown that grammatical category plays a key role in stress assignment. In these languages, some grammatical categories have a typical stress pattern and this information is used by readers. However, whether readers are sensitive to smaller distributional differences and other morpho-syntactic properties (e.g., gender, number, person) remains unclear. We addressed this issue in word and non-word reading in Italian, a language in which: (1) nouns and verbs differ in the proportion of words with a dominant stress pattern; (2) information specified by words sharing morpho-syntactic properties may contrast with other sources of information, such as stress neighborhood. Both aspects were addressed in two experiments in which context words were used to induce the desired morpho-syntactic properties. Experiment 1 showed that the relatively different proportions of stress patterns between grammatical categories do not affect stress processing in word reading. In contrast, Experiment 2 showed that information specified by words sharing morpho-syntactic properties outweighs stress neighborhood in non-word reading. Thus, while general information specified by grammatical categories may not be used by Italian readers, stress neighbors with morpho-syntactic properties congruent with those of the target stimulus have a primary role in stress assignment. These results underscore the importance of expanding investigations of stress assignment beyond single words, as current models of single-word reading seem unable to account for our results
Naturwall: active timber wall for renovation of existent buildings
The renovation of old buildings is actually the challenge to cope with increased effort in order to reduce climate global change, channeling more investment and awareness in this sense, defining more experimentations and find innovative solutions. The difficulty of carrying out an intervention on the existing buildings necessarily arise from the lack of information on the existing structure and the lack of coordinated processes between the multidisciplinary skills involved, as well as a difficulty to optimize the process that would make it even more competitive on the renovation work instead on the new construction. Naturwall is an innovative energy saving system for existent buildings by using wood in multifunctional components able to mitigate the environmental effort in building management. The project meant to introduce an industrialized design method in the renovation of existing build environment that highlights opportunities gave by "off site" production and parametric design approach, without neglecting the aesthetical values and the possibility to change the architectural image of residential and non residential constructions. The project aims to create a representative model of solution that will be promoted in Italy and widespread in other similar contex
Microphotonic parabolic light directors fabricated by two-photon lithography
We have fabricated microphotonic parabolic light directors using two-photon lithography, thin-film processing, and aperture formation by focused ion beam lithography. Optical transmission measurements through upright parabolic directors 22 μm high and 10 μm in diameter exhibit strong beam directivity with a beam divergence of 5.6°, in reasonable agreement with ray-tracing and full-field electromagnetic simulations. The results indicate the suitability of microphotonic parabolic light directors for producing collimated beams for applications in advanced solar cell and light-emitting diode designs
Multidisciplinary approach for a relapsing goiter with severe tracheal stenosis: a case report in an elderly patient
Total thyroidectomy is considered the gold standard for thyroid benign pathology treatment. Unfortunately, many partial interventions carried out in the past created many complications due to the tendency of the goiter to relapse and the formation of adherences in the anterior region of the neck. A woman 72 years of age with a relapsing goiter and severe respiratory symptomatology underwent thyroidectomy. After thyroid removal, tracheal stenosis persisted, making the positioning of a T silicon prosthesis (Montgomery’s T-tube) necessary. After 60 days, the prosthesis was replaced with a new made out of the same material but with a larger diameter and a softer consistency, which was removed after 4 months. The patient completely recovered her respiratory function and also maintained normal vocal cord activity without any kind of surgical sequelae. The full success was possible because of the involvement of different specialists
Experimental and numerical analysis of supersonic blade profiles developed for highly loaded impulse type steam turbine stages
The paper describes the results of a numerical and experimental research program addressing the aerodynamic investigation on the performance of blade profiles specifically developed for application in highly loaded impulse type turbine stages. The industrial requirements driving toward the adoption of highly loaded stage solutions are presented, along with an estimation of the profiles operating parameters. Two stator vanes and one rotor blade profile have been developed and extensively tested by means of flow field measurements and schlieren visualization in a transonic blow-down wind tunnel for linear cascades. Experimental results for the relevant operating conditions are presented, providing validation data for the CFD model used for blade design and evidencing that the main goals of the design optimization procedure have been achieved
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