254 research outputs found
“Test Tube Cetaceans”: From the Evaluation of Susceptibility to the Study of Genotoxic Effects of Different Environmental Contaminants Using Cetacean Fibroblast Cell Cultures
Population estimates of various species of cetaceans indicate that certain species have declined dramatically this century. Most studies of contamination and biomarker responses in marine mammals have been conducted using animals killed by hunting, tacitly approving this activity. The development of a series of nondestructive techniques to evaluate biomarker responses and residue levels is strongly recommended for the hazard assessment, protection and conservation of endangered species of marine mammals. A non-invasive sampling method, represented by skin biopsy or integument biopsy (epidermis, dermis and blubber), have been developed and validated in cetaceans. In this paper we present the cetacean fibroblast cell cultures obtained from the skin biopsies as the “test tube cetacean” for evaluate both the susceptibility that the genotoxicity of different environmental contaminants. Fibroblast cell cultures were obtained from many species of cetaceans sampled in Mediterranean Sea (Italy) and in the Mar de Cortez (Mexico). Using test tube cetaceans we can study the relationships between contamination and biochemical responses. One of the principal applications of this developed in vitro system was the assessment of interspecies differences in the mixed function oxidase activity (Cyp1A1 and Cyp2B) induced by in vitro treatment of various contaminants, such as some Persistent Organic Pollutants (POPs) but also emerging contaminants (such as bisphenol A (BpA)) and nanoparticles, added at different concentrations. The induction of Cyp1A1 and Cyp2B was evaluated with the indirect immunofluorescence technique. Therefore, another purpose of this work was to evaluate the qualitative and quantitative MICA protein expression in fibroblast cell cultures with immunofluorescence technique as toxicological stress marker of the immune system of different species of cetaceans. Finally, In this paper we will present how to evaluate the presence of DNA damage by comet assay in test tube cetaceans, after treatment with different genotoxic compounds (for example PCBs, DDTs, PAHs, BPA)
wall to wall spatial prediction of growing stock volume based on italian national forest inventory plots and remotely sensed data
Abstract Spatial predictions of forest variables are required for supporting modern national and sub-national forest planning strategies, especially in the framework of a climate change scenario. Nowadays methods for constructing wall-to-wall maps and calculating small-area estimates of forest parameters are becoming essential components of most advanced National Forest Inventory (NFI) programs. Such methods are based on the assumption of a relationship between the forest variables and predictor variables that are available for the entire forest area. Many commonly used predictors are based on data obtained from active or passive remote sensing technologies. Italy has almost 40% of its land area covered by forests. Because of the great diversity of Italian forests with respect to composition, structure and management and underlying climatic, morphological and soil conditions, a relevant question is whether methods successfully used in less complex temperate and boreal forests may be applied successfully at country level in Italy. For a study area of more than 48,657 km2 in central Italy of which 43% is covered by forest, the study presents the results of a test regarding wall-to-wall, spatially explicit estimation of forest growing stock volume (GSV) based on field measurement of 1350 plots during the last Italian NFI. For the same area, we used potential predictor variables that are available across the whole of Italy: cloud-free mosaics of multispectral optical satellite imagery (Landsat 5 TM), microwave sensor data (JAXA PALSAR), a canopy height model (CHM) from satellite LiDAR, and auxiliary variables from climate, temperature and precipitation maps, soil maps, and a digital terrain model. Two non-parametric (random forests and k-NN) and two parametric (multiple linear regression and geographically weighted regression) prediction methods were tested to produce wall-to-wall map of growing stock volume at 23-m resolution. Pixel level predictions were used to produce small-area, province-level model-assisted estimates. The performances of all the methods were compared in terms of percent root mean-square error using a leave-one-out procedure and an independent dataset was used for validation. Results were comparable to those available for other ecological regions using similar predictors, but random forests produced the most accurate results with a pixel level R2 = 0.69 and RMSE% = 37.2% against the independent validation dataset. Model-assisted estimates were more precise than the original design-based estimates provided by the NFI
Recurrent aphthous stomatitis: Treatment and management
Background: Recurrent aphthous stomatitis consists of the presence of abrasions or ulcerations located on mucosae (oral or genital). Objectives: The aim of this article is to review the current literature providing the main causes related to recurrent aphthous stomatitis and insights into treatment and management of this clinical condition Methods: Articles matching terms that correlated with "recurrent aphthous stomatitis"were searched on PubMed, EMBASE, and Cochrane Library and selected according to their pertinence. Results: Several forms of aphthous stomatitis have been described, based on the extent (minor, major), morphology (herpetiform) and associations to other signs (Beh\ue7et syndrome or more complex inflammatory syndromes). Topical as well as systemic treatments have been described to obtain a faster remission of the aphthosis or to reduce associated symptoms such as pain. Conclusions: Recurrent aphthous stomatitis can have a mild-to-severe clinical appearance, being mainly localized on the oral mucosa or at the level of the genital area. Different strategies have been described so far for its management and treatment
ALMA FITS header keywords: a study from the archive User perspective
ALMA products are stored in the Science Archive in the form of FITS images.
It is a common idea that the FITS image headers should collect in their
keywords all the information that an archive User might want to search for in
order to quickly select, compare, or discard datasets. With this perspective in
mind, we first present a short description of the current status of the ALMA
FITS archive and images. We realized that at the moment most of the parameters
that could be useful for a general User are still missing in the archived data.
We then provide a CASA task generating the image header keywords that we
suggest to be relevant for the scientific exploitation of the ALMA archival
data. The proposed tool could be also applied to several types of
interferometer data and part of it is implemented in a web interface. An
example of the scientific application of the keywords is also discussed.Comment: 20 pages, 6 figures, ALMA Memo 613
https://library.nrao.edu/public/memos/alma/main/memo613.pd
Ultrafast insulator-to-metal phase transition as a switch to measure the spectrogram of a supercontinuum light pulse
In this letter we demonstrate the possibility to determine the temporal and spectral structure (spectrogram) of a complex light pulse exploiting the ultrafast switching character of a nonthermal photoinduced phase transition. As a proof, we use a VO2 multifilm, undergoing an ultrafast insulator-to-metal phase transition when excited by femtosecond near-infrared laser pulses. The abrupt variation in the multifilm optical properties, over a broad infrared/visible frequency range, is exploited to determine, in situ and in a simple way, the spectrogram of a supercontinuum pulse produced by a photonic crystal fiber. The determination of the structure of the pulse is mandatory to develop pump-probe experiments with frequency resolution over a broad spectral range (700-1100 nm)
KAFE: the Key-analysis Automated FITS-images Explorer
We present KAFE—the Key-analysis Automated FITS-images Explorer. KAFE is a web-based FITS
image postprocessing analysis tool designed to be applicable in the radio to sub-mm wavelength domain. KAFE
was developed to complement selected FITS files with metadata based on a uniform image analysis approach
as well as to provide advanced image diagnostic plots. It is ideally suited for data mining purposes and multiwavelength/multi-instrument data samples that require uniform data diagnostic criteria. We present the code structure and interface, the keyword definitions, the products generated for selected users’ science cases, and application examples
A spatially explicit database of wind disturbances in European forests over the period 2000-2018
Strong winds may uproot and break trees and represent a major natural disturbance for European forests. Wind disturbances have intensified over the last decades globally and are expected to further rise in view of the effects of climate change. Despite the importance of such natural disturbances, there are currently no spatially explicit databases of wind-related impact at a pan-European scale. Here, we present a new database of wind disturbances in European forests (FORWIND). FORWIND is comprised of more than 80 000 spatially delineated areas in Europe that were disturbed by wind in the period 2000-2018 and describes them in a harmonized and consistent geographical vector format. The database includes all major windstorms that occurred over the observational period (e.g. Gudrun, Kyrill, Klaus, Xynthia and Vaia) and represents approximately 30% of the reported damaging wind events in Europe. Correlation analyses between the areas in FORWIND and land cover changes retrieved from the Landsat-based Global Forest Change dataset and the MODIS Global Disturbance Index corroborate the robustness of FORWIND. Spearman rank coefficients range between 0.27 and 0.48 (p value < 0.05). When recorded forest areas are rescaled based on their damage degree, correlation increases to 0.54. Wind-damaged growing stock volumes reported in national inventories (FORESTORM dataset) are generally higher than analogous metrics provided by FORWIND in combination with satellite-based biomass and country-scale statistics of growing stock volume. The potential of FORWIND is explored for a range of challenging topics and scientific fields, including scaling relations of wind damage, forest vulnerability modelling, remote sensing monitoring of forest disturbance, representation of uprooting and breakage of trees in large-scale land surface models, and hydrogeological risks following wind damage. Overall, FORWIND represents an essential and open-access spatial source that can be used to improve the understanding, detection and prediction of wind disturbances and the consequent impacts on forest ecosystems and the land-atmosphere system. Data sharing is encouraged in order to continuously update and improve FORWIND
Measurements of branching fraction ratios and CP-asymmetries in suppressed B^- -> D(-> K^+ pi^-)K^- and B^- -> D(-> K^+ pi^-)pi^- decays
We report the first reconstruction in hadron collisions of the suppressed
decays B^- -> D(-> K^+ pi^-)K^- and B^- -> D(-> K^+ pi^-)pi^-, sensitive to the
CKM phase gamma, using data from 7 fb^-1 of integrated luminosity collected by
the CDF II detector at the Tevatron collider. We reconstruct a signal for the
B^- -> D(-> K^+ pi^-)K^- suppressed mode with a significance of 3.2 standard
deviations, and measure the ratios of the suppressed to favored branching
fractions R(K) = [22.0 \pm 8.6(stat)\pm 2.6(syst)]\times 10^-3, R^+(K) =
[42.6\pm 13.7(stat)\pm 2.8(syst)]\times 10^-3, R^-(K)= [3.8\pm 10.3(stat)\pm
2.7(syst]\times 10^-3, as well as the direct CP-violating asymmetry A(K) =
-0.82\pm 0.44(stat)\pm 0.09(syst) of this mode. Corresponding quantities for
B^- -> D(-> K^+ pi^-)pi^- decay are also reported.Comment: 8 pages, 1 figure, accepted by Phys.Rev.D Rapid Communications for
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Optical Switching in VO2 films by below-gap excitation
We study the photo-induced insulator-metal transition in VO2, correlating threshold and dynamic evolution with excitation wavelength. In high-quality single crystal samples, we find that switching can only be induced with photon energies above the 670-meV gap. This contrasts with the case of polycrystalline films, where formation of the metallic state can also be triggered with photon energies as low as 180 meV, well below the bandgap. Perfection of this process may be conducive to novel schemes for optical switches, limiters and detectors, operating at room temperature in the mid-IR
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