24,464 research outputs found
Ground-based geological mapping integrated by UAs in the Chiavenna area (Central Alps): examples of application in the frame of the CARG project
No full textGround-based geological mapping integrated by UAs in the Chiavenna area (Central Alps):
examples of application in the frame of the CARG project
Tartarotti P.*1, Apuani T.', Arrigoni F.', Conforto A.', Pigazzi E.', Tantardini D.' & Toffolon G.?
1 Dipartimento di Scienze della Terra
"A. Desio", Università di Milano. 2 Contractor CARG-Valchiavenna Project.
Corresponding author e-mail: [email protected]
Traditional ground-based mapping of cry stalline basements is essential to unravel their tectono-metamorphic
evolution. However, the structural setting of metamorphic terranes is most of the time complicated by the
polyphase history, not least by neotectonics. Many scientific difficulties can be overcome by implementing
the field work with analytical investigations, such as chemical or geochronological analyses, that may solve
several geological issues as long as the structural and microstructural features are well constrained. Recently, an
interest has been growing in advanced technologies dedicated to data acquisition and applications in geological
mapping. Nowadays, unmanned aerial systems (UASs) such as drones are more and more utilised, especially
in mineral exploration and mine exploitation (.g., Honarmand & Shahriari, 2021). Drone photogrammetry
is particularly useful in inaccessible areas, opening a new perspective for all kinds of ground operators. We
used DJI Mavic 2 Pro and DJI Mavic Mini drones to implement the traditional field work on crystalline
basements in the Chiavenna area (Central Alps), within the frame of the project '
"Carta Geologica d'Italia
at scale 1:50.000 - CARG', covering ca. 700 kmq. This area is characterized by altitudes ranging between
200 and 3300 m a.s.l., and by a hostile topography with steep slopes and few road access that make many
outcrops scarcely or not reachable. Most of the territory sees the exposure of polymetamorphic basements of
the Penninic Suretta, Tambò, and Adula Nappes, separated by sheets of Mesozoic metasedimentary rocks, the
Chiavenna unit, interpreted as a remnant of the Valais Ocean, and the Gruf Complex, whose attribution is still
uncertain, intruded in the southeastern portion by the Bergell pluton (Schmid et al., 1996). UAS tools turn to
be fundamental in such kind of terrains, whose applications regard the recognition of different lithologies on
exposed surfaces, structures, morphologies, and landslides. Reiteration of field and intermediate laboratory
work, with UAS-assisted surveys is necessary to finalise the geological mapping and its interpretation.
Honarmand M. & Shahriari H. (2021) - Geological Mapping Using Drone-Based Photogrammetry: An Application for
Exploration of Vein-Type Cu Mineralization. Minerals, 11(6), 585.
Schmid S. M., Pfiffner O. A., Froitzheim N., Schönborn G. & Kissling E. (1996) - Geophysical-geological transect and
tectonic evolution of the Swiss-Italian Alps. Tectonics, 15(5), 1036-1064
Pharmacokinetics and pharmacodynamics of acetylsalicylic acid after intravenous and oral administration to healthy volunteers
No full textJ Nagelschmitz,1 M Blunck,1 J Kraetzschmar,1 M Ludwig,1 G Wensing,1 T Hohlfeld2 1Bayer HealthCare AG, Clinical Pharmacology, Wuppertal, Germany; 2Institut für Pharmakologie und Klinische Pharmakologie, Heinrich-Heine Universität Düsseldorf, Düsseldorf, Germany Background: The pharmacology of single doses of acetylsalicylic acid (ASA) administered intravenously (250 or 500 mg) or orally (100, 300, or 500 mg) was evaluated in a randomized, placebo-controlled, crossover study. Methods: Blood and urine samples were collected before and up to 24 hours after administration of ASA in 22 healthy volunteers. Pharmacokinetic parameters and measurements of platelet aggregation were determined using validated techniques. Results: A comparison between administration routes showed that the geometric mean dose-corrected peak concentrations (Cmax/D) and the geometric mean dose-corrected area under the curve (AUC0–∞/D) were higher following intravenous administration of ASA 500 mg compared with oral administration (estimated ratios were 11.23 and 2.03, respectively). Complete inhibition of platelet aggregation was achieved within 5 minutes with both intravenous ASA doses, reflecting a rapid onset of inhibition that was not observed with oral dosing. At 5 minutes after administration, the mean reduction in arachidonic acid-induced thromboxane B2 synthesis ex vivo was 99.3% with ASA 250 mg intravenously and 99.7% with ASA 500 mg intravenously. In exploratory analyses, thromboxane B2 synthesis was significantly lower after intravenous versus oral ASA 500 mg (P<0.0001) at each observed time point up to the first hour after administration. Concentrations of 6-keto-prostaglandin1α at 5 and 20 minutes after dosing were also significantly lower with ASA 500 mg intravenously than with ASA 500 mg orally. Conclusion: This study demonstrates that intravenous ASA provides more rapid and consistent platelet inhibition than oral ASA within the first hour after dosing. Keywords: intravenous acetylsalicylic acid, oral acetylsalicylic acid, pharmacodynamics, pharmacokinetics, platelet aggregation, cyclooxygenase-1, thromboxane formatio
Mesophilic-hydrothermal-thermophilic (M-H-T) digestion of green corn straw
No full textMesophilic-hydrothermal (80-160 degrees C, 30 min)-thermophilic (M-H-T) digestion and control tests of mesophilic (M), thermophilic (T), hydrothermal-mesophilic (H-M), and mesophilic-thermophilic digestion (M-T) of green corn straw were conducted for a 20-day fermentation period. The results indicate that M-H-T is an efficient method to improve methane production. A maximum methane yield of 371.74 mL/g volatile solid was obtained by the M (3 days)-H (140 degrees C)-T (17 days) process, which was 20.44%, 16.55%, 31.44%, and 14.31% higher than the yields of the M, T, 140-M, and M-T processes. The enhanced methane production was attributed to (1) the improved hemicellulose degradation and lignin disorganization; (2) prevention of the degradation of soluble sugar, easily hydrolyzed hemicellulose and cellulose into furfural and methylfurfural; and (3) lack of formation of Maillard reaction products during initial hydrothermal treatment. (C) 2015 Elsevier Ltd. All rights reserved
C3H7NO2S effect on concrete steel-rebar corrosion in 0.5 M H2SO4 simulating industrial/microbial environment
No full textThis paper investigates C3H7NO2S (Cysteine) effect on the inhibition of reinforcing steel corrosion in concrete immersed in 0.5 M H2SO4, for simulating industrial/microbial environment. Different C3H7NO2S concentrations were admixed, in duplicates, in steel-reinforced concrete samples that were partially immersed in the acidic sulphate environment. Electrochemical monitoring techniques of open circuit potential, as per ASTM C876-91 R99, and corrosion rate, by linear polarization resistance, were then employed for studying anticorrosion effect in steel-reinforced concrete samples by the organic hydrocarbon admixture. Analyses of electrochemical test-data followed ASTM G16-95 R04 prescriptions including probability distribution modeling with significant testing by Kolmogorov-Smirnov and student's t-tests statistics. Results established that all datasets of corrosion potential distributed like the Normal, the Gumbel and the Weibull distributions but that only the Weibull model described all the corrosion rate datasets in the study, as per the Kolmogorov-Smirnov test-statistics. Results of the student's t-test showed that differences of corrosion test-data between duplicated samples with the same C3H7NO2S concentrations were not statistically significant. These results indicated that 0.06878 M C3H7NO2S exhibited optimal inhibition efficiency η = 90.52±1.29% on reinforcing steel corrosion in the concrete samples immersed in 0.5 M H2SO4, simulating industrial/microbial service-environment
The long-wavelength view of GG Tau A: rocks in the ring world
No full textWe present the first detection of GG Tau A at centimetre wavelengths, made with the Arcminute Microkelvin Imager Large Array at a frequency of 16 GHz (λ = 1.8 cm). The source is detected at >6 σrms with an integrated flux density of S16GHz = 249 ± 45 µJy. We use these new centimetre-wave data, in conjunction with additional measurements compiled from the literature, to investigate the long-wavelength tail of the dust emission from this unusual protoplanetary system. We use an MCMC-based method to determine maximum likelihood parameters for a simple parametric spectral model and consider the opacity and mass of the dust contributing to the microwave emission. We derive a dust mass of Md ~ 0.1 Msun, constrain the dimensions of the emitting region and find that the opacity index at λ > 7 mm is less than unity, implying a contribution to the dust population from grains exceeding ~4 cm in size. We suggest that this indicates coagulation within the GG Tau A system has proceeded to the point where dust grains have grown to the size of small rocks with dimensions of a few centimetres. Considering the relatively young age of the GG Tau association in combination with the low derived disc mass, we suggest that this system may provide a useful test case for rapid core accretion planet formation models
Correction to: Ceftaroline Fosamil for Treatment of Pediatric Complicated Skin and Soft Tissue Infections and Community-Acquired Pneumonia (Pediatric Drugs, (2021), 23, 6, (549-563), 10.1007/s40272-021-00468-w)
No full textThe article “Ceftaroline Fosamil for Treatment of Pediatric Complicated Skin and Soft Tissue Infections and Community-Acquired Pneumonia”, written by Susanna Esposito,Timothy J, Carrothers ,Todd Riccobene , Gregory G. Stone and Michal Kantecki was originally published electronically on the publisher’s internet portal on 31st August 2021 without open access. With the author(s)’ decision to opt for Open Choice the copyright of the article changed on 20th September 2021 to © The Author(s) 2021 and the article is forthwith distributed under a Creative Commons Attribution-Noncommercial 4.0 International License, which permits any non-commercial use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc/4.0/. The original article has been corrected
Discovery of an optical counterpart to the hyperluminous X-ray source in ESO 243-49
No full textThe existence of black holes of masses similar to 10(2)-10(5)M(circle dot) has important implications for the formation and evolution of star clusters and supermassive black holes. One of the strongest candidates to date is the hyperluminous X-ray source (HLX1), possibly located in the S0- a galaxy ESO 243-49, but the lack of an identifiable optical counterpart had hampered its interpretation. Using the Magellan telescope, we have discovered an unresolved optical source with R = 23.80 +/- 0.25 mag and V = 24.5 +/- 0.3 mag within HLX1's positional error circle. This implies an average X-ray/optical flux ratio similar to 500. Taking the same distance as ESO 243-49, we obtain an intrinsic brightness M-R = -11.0 +/- 0.3 mag, comparable to that of a massive globular cluster. Alternatively, the optical source is consistent with a main-sequence M star in the Galactic halo (for example an M4.4 star at approximate to 2.5 kpc). We also examined the properties of ESO 243-49 by combining Swift/Ultraviolet/Optical Telescope (UVOT) observations with stellar population modelling. We found that the overall emission is dominated by a similar to 5-Gyr-old stellar population, but the UV emission at approximate to 2000 angstrom is mostly due to ongoing star formation at a rate of similar to 0.03M(circle dot) yr(-1). The UV emission is more intense (at least a 9 sigma enhancement above the mean) north-east of the nucleus, in the same quadrant as HLX1. With the combined optical and X-ray measurements, we put constraints on the nature of HLX1. We rule out a foreground star and a background AGN. Two alternative scenarios are still viable. HLX1 could be an accreting intermediate mass black hole in a star cluster, which may itself be the stripped nucleus of a dwarf galaxy that passed through ESO 243-49, an event which might have caused the current episode of star formation. Or, it could be a neutron star in the Galactic halo, accreting from an M4-M5 donor star
Self-archiving practice and the influence of publisher policies in the social sciences
No full textAuthors in different disciplines exhibit very different behaviours on the so-called ‘green’ road to open access, i.e. self-archiving. This study looks at the self-archiving behaviour of authors publishing in leading journals in six social science disciplines. It tests the hypothesis that authors are self-archiving according to the norms of their respective disciplines rather than following self-archiving policies of publishers, and that, as a result, they are self-archiving significant numbers of publisher PDF versions. It finds significant levels of
self-archiving, as well as significant self-archiving of
the publisher PDF version, in all the disciplines
investigated. Publishers’ self-archiving policies have
no influence on author self-archiving practice
Hundreds of variants clustered in genomic loci and biological pathways affect human height
No full textMost common human traits and diseases have a polygenic pattern of inheritance: DNA sequence variants at many genetic loci influence the phenotype. Genome-wide association (GWA) studies have identified more than 600 variants associated with human traits(1), but these typically explain small fractions of phenotypic variation, raising questions about the use of further studies. Here, using 183,727 individuals, we show that hundreds of genetic variants, in at least 180 loci, influence adult height, a highly heritable and classic polygenic trait(2,3). The large number of loci reveals patterns with important implications for genetic studies of common human diseases and traits. First, the 180 loci are not random, but instead are enriched for genes that are connected in biological pathways (P = 0.016) and that underlie skeletal growth defects (P<0.001). Second, the likely causal gene is often located near the most strongly associated variant: in 13 of 21 loci containing a known skeletal growth gene, that gene was closest to the associated variant. Third, at least 19 loci have multiple independently associated variants, suggesting that allelic heterogeneity is a frequent feature of polygenic traits, that comprehensive explorations of already-discovered loci should discover additional variants and that an appreciable fraction of associated loci may have been identified. Fourth, associated variants are enriched for likely functional effects on genes, being over-represented among variants that alter amino-acid structure of proteins and expression levels of nearby genes. Our data explain approximately 10% of the phenotypic variation in height, and we estimate that unidentified common variants of similar effect sizes would increase this figure to approximately 16% of phenotypic variation (approximately 20% of heritable variation). Although additional approaches are needed to dissect the genetic architecture of polygenic human traits fully, our findings indicate that GWA studies can identify large numbers of loci that implicate biologically relevant genes and pathways
The AM Canum Venaticorum binary SDSS J173047.59+554518.5
No full textThe AM Canum Venaticorum (AM CVn) binaries are a rare group of hydrogen-deficient, ultrashort period, mass-transferring white dwarf binaries and are possible progenitors of Type Ia supernovae. We present time-resolved spectroscopy of the recently discovered AM CVn binary SDSS J173047.59+554518.5. The average spectrum shows strong double-peaked helium emission lines, as well as a variety of metal lines, including neon; this is the second detection of neon in an AM CVn binary, after the much brighter system GP Com. We detect no calcium in the accretion disc, a puzzling feature that has been noted in many of the longer period AM CVn binaries. We measure an orbital period, from the radial velocities of the emission lines, of 35.2 ± 0.2 min, confirming the ultracompact binary nature of the system. The emission lines seen in SDSS J1730 are very narrow, although double-peaked, implying a low-inclination, face-on accretion disc; using the measured velocities of the line peaks, we estimate i ≤ 11°. This low inclination makes SDSS J1730 an excellent system for the identification of emission lines
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