Search results for "T REG"
showing 10 items of 208 documents
IN-VITRO REGENERATION OF CALENDULA MARITIMA GUSS. (ASTERACEAE), A THREATENED PLANT ENDEMIC TO WESTERN SICILY
2016
Calendula maritima is a critically endangered endemic plant of Western Sicily. Besides habitat destruction, the hybridization with the contiguous congener species C. fulgida is a major threat to its conservation. For this reason, seed-based propagation and seed storage are not appropriate for conservation purposes. In the present paper we describe a rapid and prolific in vitro plant regeneration method by direct organogenesis from leaves of C. maritima. Leaf explants were cultured on solid Murashige and Skoog (MS) medium in the presence of several plant growth regulator combinations. The best shoot multiplication rate (2.5 shoots/explant) was obtained on the medium containing 4.4 µM 6-benzy…
Analysis of enantiomers giving partially overlapped peaks by using different treatments of the chromatographic ultraviolet signals: quantification of…
2001
Abstract Different strategies for the quantification of partially coeluting optical isomers have been investigated. The methods tested are based on the use of different features as the analytical UV signals: peak heights, perpendicular drop areas, first and second derivatives of the chromatograms, peak areas obtained by deconvolution of the overlapped peaks with data fitting optimization, and a multivariate model (principal component regression, PCR). The amphetamine-derivative drug pseudoephedrine was selected as a model compound. For chromatography, LiChrospher 100 RP 18 and a mobile-phase consisting of methanol and a solution of carboxymethyl-β-cyclodextrin (the chiral selector) were use…
Scad-elastic net and the estimation of individual tourism expenditure determinants
2014
This paper introduces the use of scad-elastic net in the assessment of the determinants of individual tourist spending. This technique approaches two main estimation-related issues of primary importance. So far studies of tourism literature have made a wide use of classic regressions, whose results might be affected by multicollinearity. In addition, because of the absence of robust economic theory on tourism behavior, regressor selection is often left to researcher's choice when not driven by non-optimal automatic criteria. Scad-elastic net is an OLS model that accounts for both these problems by including two types of parameters constraints, namely the smoothly clipped absolute deviation …
The Impact of Barriers on Export Behavior of a Developing Country Firms: Evidence from Tanzania
2012
The purpose of this paper is to identify main export barriers and to test empirically their impact on export behavior. A survey of 122 manufacturing firms was conducted in Tanzania between October 2008 and February 2009. The survey data were analyzed using factor analysis and the Tobit regression model. Factor analysis identified five significant barrier factors: lack of export market knowledge and information, export supply capacity constraints, inadequate export financing, inefficient regulatory framework, and poor infrastructure. The impact of the barriers on export behavior was then tested using the Tobit regression model. The results of the Tobit estimation indicated that the lack of e…
In-vitro regeneration of Calendula maritima Guss. (Asteraceae), a threatened plant endemic to Western Sicily
2016
Calendula maritima is a critically endangered endemic plant of Western Sicily. Besides habitat destruction, the hybridization with the contiguous congener species C. fulgida is a major threat to its conservation. For this reason, seed-based propagation and seed storage are not appropriate for conservation purposes. In the present paper we describe a rapid and prolific In vitro plant regeneration method by direct organogenesis from leaves of C. maritima. Leaf explants were cultured on solid Murashige and Skoog (MS) medium in the presence of several plant growth regulator combinations. The best shoot multiplication rate (2.5 shoots/explant) was obtained on the medium containing 4.4 mu M 6-ben…
The paradox of (Inter)net neutrality: An experiment on ex-ante antitrust regulation✰
2022
Abstract Net neutrality has been the most relevant and heavily debated Internet regulation policy of the last decade. Net neutrality aims to prohibit discrimination between data packages in terms of content, origin, destination, or type of equipment used. However, the Big Tech companies, sheltered by the net neutrality policy, have flourished. They now have the power to exclude minor companies, and therefore their contents, from the Internet market in de facto defiance of the net neutrality principle. Academic results regarding this net neutrality paradox are still ambiguous. To represent the current Internet market distortions and analyze a potential tool to adjust and strengthen the net n…
“Generalist” Journals between Dissemination of Economics and Regime Propaganda
2019
Early in the 20th, generalist journals – a kind of press which had its major diffusion in the nineteenth century – continue to accommodate the contributions of economists offering a specific debating space. However, with the affirmation of fascist ideology, generalist periodicals progressively ceased to exist or to host economists’ articles. Thus, the main object of this research consists in clarifying what could be intended by “generalism” and in relation to which events and ideological pressures it disappeared as a different way to do journalism in a dialectic interplay with specialization. The paper reviews the panorama of generalist journals focusing on the impact of the Fascist regime …
Influence of metabolic state (substrate oxidation ratio) on food liking, food wanting and food consumption in young men
2011
Meeting Abstract n°484 . WOS: 000288862900481; International audience
La pianificazione forestale in Sicilia: storia e recenti evoluzioni
2018
In Sicilia la pianificazione forestale ha avuto di recente una svolta resasi necessaria sia per motivi richiesti dall’autorità europea e da quella nazionale, sia per un’oggettiva necessità del territorio. Dal punto di vista normativo la storia degli ultimi decenni ha visto la Sicilia dotarsi di norme e giuridicamente all’avanguardia e lungimiranti dal punto di vista della conservazione del patrimonio naturale. Si fa infatti riferimento ai piani di assestamento forestale per la gestione del patrimonio boschivo isolano dalle leggi regionali del 1989, del 1996, del 2004 con l’emanazione di linee guida regionali e della LR 14/2006. Quest’ultima in particolare richiamava anche alla necessità di …
Small-Signal Modeling of a Controlled Transformer Parallel Regulator as a Multiple Output Converter High Efficient Post-Regulator
2004
This paper presents a post-regulator based on the use of a controlled transformer, which adds or subtracts an additional voltage to the output filter of a converter in order to regulate its output voltage. So, their actuation is complementary to that of more known post-regulators, such as the magnetic amplifier (magamp) and synchronous switch post-regulator (SSPR), because the regulation is achieved by controlling the voltage across the filter inductor instead of its charge time. Besides, the post-regulator processes the power in parallel to the one flowing from input to output and only handles a percentage of it. The post-regulation by controlled transformer is suitable of being employed i…