The ideal of the certainty in law: the skin and the heart of law

The doubt about certainty like an absolute value in law and as an ideal full in legal system (argument about impossibility) is a controversial fact in contemporary legal theory. In this text I examine some contemporary doctrines about the classic understanding (in critical sense) of this ideal. I have selected the most representative doctrines: doctrine about "open texture of Law" (H.L.A. Hart), starting point in this discussion; doctrine about "Il Diritto mite" (G. Zagrebelsky), from the continental European legal tradition at present; and doctrine about "vagueness in Law" (T.A.O. Endicott), this doctrine is the most recent, from the Anglo-Saxon legal tradition. Finally, in Conclusions, I analyze if this doubt (argument about impossibility) contaminates (in some sense) to the concept of law or to the characteristics that describe law in the contemporary Constitutional State

Trade, extent of the market and economic growth 1960-1996

We find that trade and domestic market size are robust determinants of economic growth over the 1960-1996 period when trade openness is measured as the US dollar value of imports and exports relative to GDP in PPP US$('real openness'). When trade openness is measured as the US dollar value of imports and exports relative to GDP in exchange rate US$ ('nominal openness') however, trade and the size of domestic markets are often non-robust determinants of growth. We argue that real openness is the more appropriate measure of trade and that our empirical results should be seen as evidence in favor of the extent-of-the-market hypothesis.Extent of the market, institutions, growth

Output composition and the US output volatility decline

We argue that the role played by output-composition changes on the decline in US output volatility has been incorrectly assessed in the recent literature. We obtain that shifts across broad sectors in the economy account for about thirty-percent of the volatility decline since the 1950’s.volatility, business fluctuations

Trade and productivity

We estimate the effect of international trade on average labor productivity at the country level. Our empirical approach relies on summary measures of trade that, we argue, are preferable on both theoretical and empirical grounds to the one conventionally used. In contrast to the marginally significant and non-robust effects of trade on productivity found previously, our estimates are highly significant and robust even when we include institutional quality and geographic factors in the empirical analysis. We also examine the channels through which trade and institutional quality affect average labor productivity. Our finding is that trade works through labor efficiency, while institutional quality works through physical and human capital accumulation. We conclude with an exploratory analysis of the role of trade policies for average labor productivity.Trade, productivity, institutions trade policy

Copying, Superstars, and Artistic Creation

We provide a new perspective on the impact of unauthorized copying and copy levies on artistic creation. Our analysis emphasizes three important aspects of artistic markets: the predominance of superstars, the dynamics of talent sorting, and the importance of promotion expenditures. In the short run, piracy reduces superstars’ earnings and market share, and increases the number of niche and young artists. From a dynamic perspective, piracy may help more young artists start their careers, thereby increasing the number of highly talented artists in the long run. The long run impact on artistic creation of levies on copy equipment may crucially depend on whether their yields primarily accrue to superstars or are allocated to help young artists.artistic creation, superstars, private copy, piracy, levies

UVES Spectroscopy of T Chamaeleontis: Line Variability, Mass Accretion Rate and Spectro-astrometric Analysis

Although advances in exoplanet detection techniques have seen an increase in discoveries, observing a planet in the earliest stages of formation still remains a difficult task. Here four epochs of spectra of the transitional disk object T Cha are analysed to determine whether spectro-astrometry can be used to detect a signal from its proposed protoplanet, T Cha b. The unique properties of T Cha are also further constrained. H{\alpha} and [O I]{\lambda} 6300, the most prominent lines, were analysed using spectro-astrometry. H{\alpha} being a direct accretion tracer is the target for the T Cha b detection while [O I]{\lambda} 6300 is considered to be an indirect tracer of accretion. [O I]{\lambda} 6300 is classified as a broad low velocity component (BC LVC). The mass accretion rate was derived for all epochs using new [O I]{\lambda} 6300 LVC relationships and the H{\alpha} line luminosity. It is shown that a wind is the likely origin of the [O I]{\lambda} 6300 line and that the [O I]{\lambda} 6300 line serves as a better accretion tracer than H{\alpha} in this case. From the comparison between M acc([OI]) and M acc(H{\alpha}) it is concluded that T Cha is not an intrinsically weak accretor but rather that a significant proportion of the H{\alpha} emission tracing accretion is obscured. T Cha b is not detected in the spectro-astrometric analysis yet a detection limit of 0.5 mas is derived. The analysis in this case was hampered by spectro-astrometric artefacts and by the unique properties of T Cha. While it seems that spectro-astrometry as a means of detecting exoplanets in TDs can be challenging it can be used to put an limit on the strength of the H{\alpha} emission from accreting planetary companions and thus can have an important input into the planning of high angular resolution observations

Crossing the Gould Belt in the Orion vicinity

We present a study of the large-scale spatial distribution of 6482 RASS X-ray sources in approximately 5000 deg^2 in the direction of Orion. We examine the astrophysical properties of a sub-sample of ~100 optical counterparts, using optical spectroscopy. This sub-sample is used to investigate the space density of the RASS young star candidates by comparing X-ray number counts with Galactic model predictions. We characterize the observed sub-sample in terms of spectral type, lithium content, radial and rotational velocities, as well as iron abundance. A population synthesis model is then applied to analyze the stellar content of the RASS in the studied area. We find that stars associated with the Orion star-forming region do show a high lithium content. A population of late-type stars with lithium equivalent widths larger than Pleiades stars of the same spectral type (hence younger than ~70-100 Myr) is found widely spread over the studied area. Two new young stellar aggregates, namely "X-ray Clump 0534+22" (age~2-10 Myr) and "X-ray Clump 0430-08" (age~2-20 Myr), are also identified. The spectroscopic follow-up and comparison with Galactic model predictions reveal that the X-ray selected stellar population in the direction of Orion is characterized by three distinct components, namely the clustered, the young dispersed, and the widespread field populations. The clustered population is mainly associated with regions of recent or ongoing star formation and correlates spatially with molecular clouds. The dispersed young population follows a broad lane apparently coinciding spatially with the Gould Belt, while the widespread population consists primarily of active field stars older than 100 Myr. We expect the "bi-dimensional" picture emerging from this study to grow in depth as soon as the distance and the kinematics of the studied sources will become available from the future Gaia mission.Comment: 17 pages, 13 figures, 4 tables. Accepted for publication in Astronomy and Astrophysics. Abstract shortene

Actividad del agua de la miel y crecimiento de microorganismos osmotolerantes

El contenido en agua de 55 muestras de miel comercial osciló entre el 14,8% y el 25,0% siendo la media de 18,1 ± 2,15%. El valor aw varió entre 0,44 y 0,76 siendo la media de 0,60 ± 0,07. Ambos factores están en general posilivamente correlacionados, pero numerosas muestras individuales se apartan considerablemente de la relación general. Más de tres cuartas partes de las muestras contenían microorganismos osmófilos viables (el 50% de ellas levaduras, el 30%levaduras y hongos filamentosos y el 20% sólo hongos). Se han observado diferencias tanto en la aw limitante del crecimiento, como en la velocidad de crecimiento a diferentes valores aw. Las levaduras, más osmotolerantes, crecieron a una aw = 0,68 mientras la aw mínima de crecimiento de los hongos en ocho meses es >0,70