3,041 research outputs found
Discrete choice models of labour suppluy, behavioural microsimulation and the Spanish tax reform
In this paper, we demonstrate the potential of behavioural microsimulation models as powerful tools for the ex ante evaluation of public policies. The subject of our analysis is the impact of recent Spanish Income Tax reforms on efficiency and household and social welfare. We also analyze the likely effects of some basic income - flat tax and vital minimum - flat tax schemes. The analysis is carried out using a microsimulation model in which labour supply is explicitly taken into account. Instead of following the traditional continuous approach (Hausman 1981, 1985a, and 1985b), we estimate the direct utility function using the methodology proposed by Van Soest (1995). Our data come from a sample of Spanish individuals in the 1995 wave of the EC Household Panel. We show that in the Spanish case, the redistribution policies considered have only little impact on the efficiency of the economy. On the contrary, they strongly affect social welfare.microsimulation models ; evaluation of public policies
Small-scale flows in SUMER and TRACE high-cadence co-observations
We report on the physical properties of small-scale transient flows observed
simultaneously at high cadence with the SUMER spectrometer and the TRACE imager
in the plage area of an active region. Our major objective is to provide a
better understanding of the nature of transient phenomena in the solar
atmosphere by using high-cadence imager and spectrometer co-observations at
similar spatial and temporal resolution. A sequence of TRACE Fe IX/X 171 A and
high-resolution MDI images were analysed together with simultaneously obtained
SUMER observations in spectral lines covering a temperature range from 10 000 K
to 1 MK. We reveal the existence of numerous transient flows in small-scale
loops (up to 30 Mm) observed in the plage area of an active region. These flows
have temperatures from 10 000 K (the low temperature limit of our observations)
to 250 000 K. The coronal response of these features is uncertain due to a
blending of the observed coronal line Mg X 624.85 A. The duration of the events
ranges from 60 s to 19 min depending on the loop size. Some of the flows reach
supersonic velocities. The Doppler shifts often associated with explosive
events or bi-directional jets can actually be identified with flows (some of
them reaching supersonic velocities) in small-scale loops. Additionally, we
demonstrate how a line-of-sight effect can give misleading information on the
nature of the observed phenomena if only either an imager or a spectrometer is
used.Comment: 7 pages, 6 figures, accepted by A&
Surface-enhanced Raman spectroscopy in 3D electrospun nanofiber mats coated with gold nanorods
Nanofibers functionalized by metal nanostructures and particles are exploited
as effective flexible substrates for SERS analysis. Their complex
three-dimensional structure may provide Raman signals enhanced by orders of
magnitude compared to untextured surfaces. Understanding the origin of such
improved performances is therefore very important for pushing nanofiber-based
analytical technologies to their upper limit. Here we report on polymer
nanofiber mats which can be exploited as substrates for enhancing the Raman
spectra of adsorbed probe molecules. The increased surface area and the
scattering of light in the nanofibrous system are individually analyzed as
mechanisms to enhance Raman scattering. The deposition of gold nanorods on the
fibers further amplifies Raman signals due to SERS. This study suggests that
Raman signals can be finely tuned in intensity and effectively enhanced in
nanofiber mats and arrays by properly tailoring the architecture, composition,
and light-scattering properties of the complex networks of filaments.Comment: 29 pages, 9 figures, 1 Tabl
Molecular and taxonomic characterization of a endophytic fungus isolated from Helleborus bocconei subsp. intermedius (Ranunculaceae)
A non-sporulating fungus was isolated from different organs of Helleborus bocconei subsp. intermedius (Ranunculaceae) endemic to southern Italy and Sicily, known for the traditional use of dried roots in the treatment of lung diseases of cattle and horses.
Molecular characterization of endophytic fungus based on the internal transcribed spacer (ITS) region of the rRNA gene sequences was done. The DNA sequence of full length ITS region of the studied fungus was a 100% match to that of Chaetomium strumarium strain dH 21642 (GenBank accession number JX280851.1). The morphological characters of colony and mycelium of this microfungus are reported here
Discrete choice models of labour suppluy, behavioural microsimulation and the Spanish tax reform
In this paper, we demonstrate the potential of behavioural microsimulation models as powerful tools for the ex ante evaluation of public policies. The subject of our analysis is the impact of recent Spanish Income Tax reforms on efficiency and household and social welfare. We also analyze the likely effects of some basic income - flat tax and vital minimum - flat tax schemes. The analysis is carried out using a microsimulation model in which labour supply is explicitly taken into account. Instead of following the traditional continuous approach (Hausman 1981, 1985a, and 1985b), we estimate the direct utility function using the methodology proposed by Van Soest (1995). Our data come from a sample of Spanish individuals in the 1995 wave of the EC Household Panel. We show that in the Spanish case, the redistribution policies considered have only little impact on the efficiency of the economy. On the contrary, they strongly affect social welfare.Dans cet article, on dĂ©montre le potentiel des modĂšles de microsimulation avec comportements dans l'Ă©valuation ex ante des politiques publiques. Le sujet de notre analyse est l'impact sur l'efficacitĂ© et sur le bien-ĂȘtre des mĂ©nages, des rĂ©formes rĂ©centes de l'impĂŽt sur les revenus implĂ©mentĂ©es en Espagne. On analyse aussi les effets de certains scĂ©narios de rĂ©forme inspirĂ©s de la logique du revenu minimum - impĂŽt linĂ©aire. L'analyse est effectuĂ©e Ă l'aide d'un modĂšle de microsimulation avec rĂ©actions d'offre de travail. Au lieu de suivre l'approche traditionnelle Ă la Hausman (1981, 1985a, 1985b), on estime directement les paramĂštres de la fonction d'utilitĂ© en employant la mĂ©thodologie proposĂ©e par Van Soest (1995). Les donnĂ©es ont Ă©tĂ© rĂ©cupĂ©rĂ©es Ă partir de la vague 1995 du Panel europĂ©en des mĂ©nages (ECHP). On dĂ©montre que, dans le cas espagnol, les politiques redistributives implĂ©mentĂ©es ont des effets mineurs sur l'efficacitĂ© Ă©conomique, par contre, elles augmentent de façon importante le bien-ĂȘtre social
Insights in disease management - Editorial
Editorial on the Research Topic
Insights in disease management
The Research Topic âInsights in Disease Managementâ brings together innovative Research Topics from the disease management sector. This is a key time to reduce losses to diseases so that we can produce more food that we need for the growing global population but also to control diseases in a way that minimises the environmental footprint of crop production. The issue covers insights using examples in both protected and field crops, covering most pathogen groups â bacteria (Reglinski et al.), viruses (Codod et al.), fungi (Dutta et al.; Sangiorgio et al.), and oomycetes (Sharma et al.). Underpinning many current approaches to disease management is the idea of integrated pest management, which is often portrayed as a triangle representing different tiers of approaches. The foundations of the IPM triangle are practices such as crop rotation to separate crops and pathogens in space and time, use of resistant varieties, and various effects of management practices such as under-sowing or inter-cropping to alter the microclimate, release biofumigants, maintain beneficial microbes or to act as a physical barrier. Papers in this issue connected with this layer of the IPM triangle cover aspects such as improved host resistance with marker-assisted selection, genome sequencing, and improved understanding of resistance genes (Sharma et al.). Also connected to host resistance is the paper by Reglinski et al. except that this concerns host resistance induced by application of a chemical elicitor. This human intervention is preferable to applications of chemical pesticides (usually depicted at the top of the IPM triangle to represent a measure used only as a last resort), which despite often providing efficient disease control and associated benefits of enhanced yield, is acknowledged to have potential non-target effects in the environment. One such non-target effect is the impact of fungicides and other pesticides on microbial endophytes and more broadly, the phytobiome, which Sangiorgio et al. argue, has potential to confer a degree of natural biological control, protecting against pathogens both on the plant surface and within host tissues. They review how genetic sequencing techniques are providing new insights into the degree of protection conferred by the phytobiome towards pathogens in addition to other roles affecting resistance to abiotic stress and nutrient uptake, ultimately affecting plant phenotype, growth, yield and quality. They conclude that future research on plant disease control should also consider impacts to microbe-mediated plant fitness. Indeed, even applications of biological control agents have potential to affect the phytobiome, but this approach is nevertheless regarded as less damaging to the environment compared to chemical control. One of the main biocontrol agents that has been used successfully for over 50 years is Trichoderma. This fungal genus is reviewed by Dutta et al., covering its use as a bio-fungicide, long-term biocontrol agent, defence activator and plant growth stimulator.
The use of available biologicals or chemical control options are greatly enhanced by monitoring and forecasting schemes to indicate exactly when the target pathogen will occur. This is increasingly being seen as a form of precision agriculture, directing not only where but also when to make an intervention to protect crops from imminent disease. Various processes have been investigated, ranging from optical sensing from platforms such as satellites, drones or tractor and hand-held devices, to weather-based forecasts, or taking environmental samples (irrigation water, soil or the air) and performing various diagnostic tests, some of which are compatible with being automated and linked to wireless reporting. One key step in determining an efficient sampling or monitoring regime is to understand the spatial distribution of the pest or pathogen in question. The paper by Codod et al. is an example of this â explaining how the whitefly-transmitted virus complex affecting yellow squash (Cucurbita pepo) occurs initially in a sparse, random pattern, mainly around edges of fields but becomes aggregated, with spread mainly along rows, which will inform future developments to improve scouting, monitoring, and management strategies.
This issue therefore brings together the core components of IPM, including traditional epidemiological studies, bio-control and cutting-edge âomicsâ, which are currently reshaping IPM, particularly through studies of functional genomics and the microbiome. These approaches are increasingly necessary to deliver sustainable crop production that will feed the world, while having a low environmental impact
New Aloes casual aliens in Sicily
Aloë arborescens, A. brachystachys and A. maculata (Asphodelaceae) are reported for the first time as casual aliens in Sicily. A. brachystachys is new also for the alien flora of Italy
- âŠ