1,274 research outputs found
Strategic Solutions to Museum Repatriation Issues: Past, Present, Future
Over the last twenty years, international treaties and resolutions have attempted to define cultural property and reach a unilateral consensus regarding the return of these objects. The demand for repatriation has become louder and more common as claims have forced museums to find strategic solutions to reparation issues when the care and safety of objects are at risk. The history of strategic solutions to reparation is not one solely based in the contemporary, it stretches to the past, is being written today, and will remain an issue of the future. Strategic solutions have benefited both the museum and the claimant by strengthening international ties, spreading museological standards and allowing for greater accessibility to cultural objects worldwide. But at the same time, several problems cloud the effectiveness of these strategic solutions: including overtly political bias actions, expositions of the needs of source nations, and serving only the interests of the museum. This thesis seeks to address how these issues have been remedied through the use of emerging ethical standards to allow for models of sharing cultural property through the copy: the brokering and loan agreement with the appropriate source community and the digital reproduction while placing a new emphasis on building partnerships to benefit the needs of both the museum and the claimant
A "simulation chain" to define a Multidisciplinary Decision Support System for landslide risk management in pyroclastic soils
Abstract. This paper proposes a Multidisciplinary Decision Support System (MDSS) as an approach to manage rainfall-induced shallow landslides of the flow type (flowslides) in pyroclastic deposits. We stress the need to combine information from the fields of meteorology, geology, hydrology, geotechnics and economics to support the agencies engaged in land monitoring and management. The MDSS consists of a "simulation chain" to link rainfall to effects in terms of infiltration, slope stability and vulnerability. This "simulation chain" was developed at the Euro-Mediterranean Centre for Climate Change (CMCC) (meteorological aspects), at the Geotechnical Laboratory of the Second University of Naples (hydrological and geotechnical aspects) and at the Department of Economics of the University of Naples "Federico II" (economic aspects). The results obtained from the application of this simulation chain in the Cervinara area during eleven years of research allowed in-depth analysis of the mechanisms underlying a flowslide in pyroclastic soil
Hermitian clifford analysis
This paper gives an overview of some basic results on Hermitian Clifford analysis, a refinement of classical Clifford analysis dealing with functions in the kernel of two mutually adjoint Dirac operators invariant under the action of the unitary group. The set of these functions, called Hermitian monogenic, contains the set of holomorphic functions in several complex variables. The paper discusses, among other results, the Fischer decomposition, the Cauchy–Kovalevskaya extension problem, the axiomatic radial algebra, and also some algebraic analysis of the system associated with Hermitian monogenic functions. While the Cauchy–Kovalevskaya extension problem can be carried out for the Hermitian monogenic system, this system imposes severe constraints on the initial Cauchy data. There exists a subsystem of the Hermitian monogenic system in which these constraints can be avoided. This subsystem, called submonogenic system, will also be discussed in the paper
Remittances and Household Expenditure Allocation Behavior in Kenya
This paper examines the effect of remittances on household spending in Kenya using household survey data from World Bank 2009 African Migration Project. A fractional multinomial logit model is used to estimate the effect of remittances on the share of expenditure on food, education, health, investments, consumer durables, housing and land, and ‘others’.The results indicate that external remittances increase the share of total household expenditure allocated to education, consumer durables and housing and reduce the share of total household expendituredevoted to food and physical investments. Internal remittance has a positive effect on the share of total household expenditure devoted to food. Once endogeneity is controlled for, external remittances have a positive effect on household spending on investment while internal remittances reduce the share of expenditure on education and ‘others’. Key words: remittances, household expenditure, fractional multinomial logit, Kenya.     Â
Comparing Methods for the Analysis of δ 13C in Falanghina Grape Must from Different Pedoclimatic Conditions
Agroforestry applications in viticulture are considered a promising strategy to improve vine water status by mitigating the threats of increasing drought due to climate change. The analysis of δ13 C is often used in viticulture to understand vine water use. In this study, the analysis of δ13 C was performed on the must of Falanghina grapevines growing in different pedoclimatic conditions. The aim was to compare the results obtained by the application of two different methodologies, using the whole must or extracted sugars as the matrix. The results showed that the δ13 C values obtained by applying the two methodologies were comparable in all analyzed vineyards independently from the pedoclimatic conditions. Indeed, the proposed method of extraction of the δ13 C on the must as a whole can be both cost-and time-saving for the analysis. This is valuable, considering that the δ13 C of must is becoming more and more used as indicator of vines’ water use. Therefore, the possibility to utilize a simplified method of extraction would enhance the application of the δ13 C at a larger scale to evaluate vine adaptation in the context of climate-change-driven increases in drought
Detection of an atmosphere around the super-Earth 55 Cancri e
We report the analysis of two new spectroscopic observations of the
super-Earth 55 Cancri e, in the near infrared, obtained with the WFC3 camera
onboard the HST. 55 Cancri e orbits so close to its parent star, that
temperatures much higher than 2000 K are expected on its surface. Given the
brightness of 55 Cancri, the observations were obtained in scanning mode,
adopting a very long scanning length and a very high scanning speed. We use our
specialized pipeline to take into account systematics introduced by these
observational parameters when coupled with the geometrical distortions of the
instrument. We measure the transit depth per wavelength channel with an average
relative uncertainty of 22 ppm per visit and find modulations that depart from
a straight line model with a 6 confidence level. These results suggest
that 55 Cancri e is surrounded by an atmosphere, which is probably
hydrogen-rich. Our fully Bayesian spectral retrieval code, T-REx, has
identified HCN to be the most likely molecular candidate able to explain the
features at 1.42 and 1.54 m. While additional spectroscopic observations
in a broader wavelength range in the infrared will be needed to confirm the HCN
detection, we discuss here the implications of such result. Our chemical model,
developed with combustion specialists, indicates that relatively high mixing
ratios of HCN may be caused by a high C/O ratio. This result suggests this
super-Earth is a carbon-rich environment even more exotic than previously
thought.Comment: 10 pages, 10 figures, 4 tables, Accepted for publication in Ap
A population study of gaseous exoplanets
We present here the analysis of 30 gaseous extrasolar planets, with
temperatures between 600 and 2400 K and radii between 0.35 and 1.9
. The quality of the HST/WFC3 spatially scanned data combined
with our specialized analysis tools allow us to study the largest and most
self-consistent sample of exoplanetary transmission spectra to date and examine
the collective behavior of warm and hot gaseous planets rather than isolated
case-studies. We define a new metric, the Atmospheric Detectability Index (ADI)
to evaluate the statistical significance of an atmospheric detection and find
statistically significant atmospheres around 16 planets out of the 30 analysed.
For most of the Jupiters in our sample, we find the detectability of their
atmospheres to be dependent on the planetary radius but not on the planetary
mass. This indicates that planetary gravity plays a secondary role in the state
of gaseous planetary atmospheres. We detect the presence of water vapour in all
of the statistically detectable atmospheres, and we cannot rule out its
presence in the atmospheres of the others. In addition, TiO and/or VO
signatures are detected with 4 confidence in WASP-76 b, and they are
most likely present in WASP-121 b. We find no correlation between expected
signal-to-noise and atmospheric detectability for most targets. This has
important implications for future large-scale surveys.Comment: 14 pages, 12 figures, 3 tables, published in A
Renormalizable acausal theories of classical gravity coupled with interacting quantum fields
We prove the renormalizability of various theories of classical gravity
coupled with interacting quantum fields. The models contain vertices with
dimensionality greater than four, a finite number of matter operators and a
finite or reduced number of independent couplings. An interesting class of
models is obtained from ordinary power-counting renormalizable theories,
letting the couplings depend on the scalar curvature R of spacetime. The
divergences are removed without introducing higher-derivative kinetic terms in
the gravitational sector. The metric tensor has a non-trivial running, even if
it is not quantized. The results are proved applying a certain map that
converts classical instabilities, due to higher derivatives, into classical
violations of causality, whose effects become observable at sufficiently high
energies. We study acausal Einstein-Yang-Mills theory with an R-dependent gauge
coupling in detail. We derive all-order formulas for the beta functions of the
dimensionality-six gravitational vertices induced by renormalization. Such beta
functions are related to the trace-anomaly coefficients of the matter
subsector.Comment: 36 pages; v2: CQG proof-corrected versio
Fluorescence excitation enhancement by waveguiding nanowires
The optical properties of vertical semiconductor nanowires can allow an enhancement of fluorescence from surface-bound fluorophores, a feature proven useful in biosensing. One of the contributing factors to the fluorescence enhancement is thought to be the local increase of the incident excitation light intensity in the vicinity of the nanowire surface, where fluorophores are located. However, this effect has not been experimentally studied in detail to date. Here, we quantify the excitation enhancement of fluorophores bound to a semiconductor nanowire surface by combining modelling with measurements of fluorescence photobleaching rate, indicative of the excitation light intensity, using epitaxially grown GaP nanowires. We study the excitation enhancement for nanowires with a diameter of 50-250 nm and show that excitation enhancement reaches a maximum for certain diameters, depending on the excitation wavelength. Furthermore, we find that the excitation enhancement decreases rapidly within tens of nanometers from the nanowire sidewall. The results can be used to design nanowire-based optical systems with exceptional sensitivities for bioanalytical applications
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