731 research outputs found
ANALYSIS OF METHODS FOR ASSESSING THE AIMING PROCESS IN BIATHLON SHOOTING
In rifle shooting disciplines coaches and athletes are interested in the motion of the rifle just before and immediately after shooting. Normally, commercial laser systems (e.g. Noptel, Finland) are used to measure and store the hit point of the shot and the on-target trajectory of the alignment of the weapon. A major drawback of this method lies in the necessity of attaching the laser device to the rifle. The purpose of this study was to analyse the usefulness of a video-based system developed by Baca & Kornfeind (2006), which is able to track the 2D-movement of the muzzle of the weapon automatically. The results show considerable correspondence of the on-target-trajectory and the 2D-movement of the muzzle, in particular in vertical direction. However, translation movements of the shoulder during aiming, which are rather difficult to diagnose, may cause differences in the horizontal plane
The Subluminous Supernova 2007qd: A Missing Link in a Family of Low-Luminosity Type Ia Supernovae
We present multi-band photometry and multi-epoch spectroscopy of the peculiar
Type Ia supernova (SN Ia) 2007qd, discovered by the SDSS-II Supernova Survey.
It possesses physical properties intermediate to those of the peculiar SN
2002cx and the extremely low-luminosity SN 2008ha. Optical photometry indicates
that it had an extraordinarily fast rise time of <= 10 days and a peak absolute
B magnitude of -15.4 +/- 0.2 at most, making it one of the most subluminous SN
Ia ever observed. Follow-up spectroscopy of SN 2007qd near maximum brightness
unambiguously shows the presence of intermediate-mass elements which are likely
caused by carbon/oxygen nuclear burning. Near maximum brightness, SN 2007qd had
a photospheric velocity of only 2800 km/s, similar to that of SN 2008ha but
about 4000 and 7000 km/s less than that of SN 2002cx and normal SN Ia,
respectively. We show that the peak luminosities of SN 2002cx-like objects are
highly correlated with both their light-curve stretch and photospheric
velocities. Its strong apparent connection to other SN 2002cx-like events
suggests that SN 2007qd is also a pure deflagration of a white dwarf, although
other mechanisms cannot be ruled out. It may be a critical link between SN
2008ha and the other members of the SN 2002cx-like class of objects.Comment: To be published in the Astrophysical Journal; 37 pages, 13 figures, 4
table
Type II-P Supernovae from the SDSS-II Supernova Survey and the Standardized Candle Method
We apply the Standardized Candle Method (SCM) for Type II Plateau supernovae
(SNe II-P), which relates the velocity of the ejecta of a SN to its luminosity
during the plateau, to 15 SNe II-P discovered over the three season run of the
Sloan Digital Sky Survey - II Supernova Survey. The redshifts of these SNe -
0.027 < z < 0.144 - cover a range hitherto sparsely sampled in the literature;
in particular, our SNe II-P sample contains nearly as many SNe in the Hubble
flow (z > 0.01) as all of the current literature on the SCM combined. We find
that the SDSS SNe have a very small intrinsic I-band dispersion (0.22 mag),
which can be attributed to selection effects. When the SCM is applied to the
combined SDSS-plus-literature set of SNe II-P, the dispersion increases to 0.29
mag, larger than the scatter for either set of SNe separately. We show that the
standardization cannot be further improved by eliminating SNe with positive
plateau decline rates, as proposed in Poznanski et al. (2009). We thoroughly
examine all potential systematic effects and conclude that for the SCM to be
useful for cosmology, the methods currently used to determine the Fe II
velocity at day 50 must be improved, and spectral templates able to encompass
the intrinsic variations of Type II-P SNe will be needed.Comment: Accepted for publication by ApJ; data used in this paper can be
downloaded from http://sdssdp47.fnal.gov/sdsssn/photometry/SNIIp.tgz;
citation errors correcte
Provenance evidence for Roman lead artefacts of distinct chronology from Portuguese archaeological sites
A set of 24 glandes plumbeae found at Alto dos Cacos, a Roman Republican military camp located in the Tagus valley, Portugal, was analysed by a quadrupole based ICP-MS to determine the tin (Sn) content and lead (Pb) isotope ratios. Results were compared with similar data previously obtained for fistulae plumbeae aquariae from Conimbriga, an important Lusitanian Roman centre during the Empire. Low Sn contents (â€0.01 wt%) were observed in 25% of glandes plumbeae indicating that were probably made with non-recycled lead. A similar situation was perceived for the set of fistulae aquariae, although most of the remaining fistulae present systematically higher Sn concentrations than those of glandes suggesting that lead recycling increased during the Empire. Pb isotope ratios distribution differentiated the analysed samples into two distinct groups: one composed by most of glandes plumbeae (15) and the other by the remaining glandes plumbeae (9) and all fistulae aquariae. The comparison with Pb isotope ratios of the published data for several lead ore deposits, exploited by the Roman in Iberian Peninsula, suggests that lead used in the manufacture of most of the glandes plumbeae would come from Linares-La Carolina, Alcudia Valley and Ossa Morena Zone. Also, some glandes could have been made using these ores, probably mixed with lead ores from Gallia Narbonensis (Southern France) or from Sardinia in the Mediterranean region. On the other hand, lead used in most fistulae aquariae came from Iberian mines, namely from Sierra Morena (Alcudia Valley and Linares-La Carolina mines) and Ossa Morena mining district, although in some cases, probably mixed with lead from the Iberian Pyrite Belt.info:eu-repo/semantics/publishedVersio
Evidence for Type Ia Supernova Diversity from Ultraviolet Observations with the Hubble Space Telescope
We present ultraviolet (UV) spectroscopy and photometry of four Type Ia supernovae (SNe 2004dt, 2004ef, 2005M, and 2005cf) obtained with the UV prism of the Advanced Camera for Surveys on the Hubble Space Telescope, This dataset provides unique spectral time series down to 2000 A. Significant diversity is seen in the near-maximum-light spectra (approx.2000-3500 A) for this small sample. The corresponding photometric data, together with archival data from Swift Ultraviolet/Optical Telescope observations, provide further evidence of increased dispersion in the UV emission with respect to the optical. The peak luminosities measured in the uvw lIF250W filter are found to correlate with the B-band light-curve shape parameter .(Delta)m15(B), but with much larger scatter relative to the correlation in the broad-band B band (e.g., approx. 0.4 mag versus approx. 0.2 mag for those with 0.8 3(sigma), being brighter than normal SNe Ia such as SN 2005cf by approx. 0,9 mag and approx. 2.0 mag in the uvwl1F250W and uvm2/F220W filters, respectively. We show that different progenitor metallicity or line-expansion velocities alone cannot explain such a large discrepancy. Viewing-angle effects, such as due to an asymmetric explosion, may have a significant influence on the flux emitted in the UV region. Detailed modeling is needed to disentangle and quantify the above effect
Outcomes of allogeneic stem cell transplantation among patients with acute myeloid leukemia presenting active disease: Experience of a single European Comprehensive Cancer Center
Introduction: Allogeneic hematopoietic stem cell transplantation (ASCT) represents a potentially curative approach for patients with relapsed or refractory acute myeloid leukemia (AML). We report the outcome of relapsed/refractory AML patients treated with ASCT.Method: A retrospective cohort from 1994 to 2013 that included 61 patients with diagnosis of relapsed/refractory AML. Outcomes of interest were transplant-related mortality (TRM), incidence of acute and chronic graft-versus-host disease (GVHD), relapse incidence, progression-free survival (PFS) and overall survival (OS). Statistical significance was set at p<0.05.Results: The median age was 61 years (range 1 to 65). The cumulative incidence of 90 days, 1 year, and 3 years TRM were 60%, 26.7%, and 13.3%, respectively (p< 0.001). The incidence of relapse was 21.7% at 1 year, 13% at 3 years, and 8.7% at 5 years. Median OS was estimated to be 8 months (95CI 3.266-12.734) and median PFS, 3 months (95CI 1.835-4.165).Conclusion: In our cohort, TRM in first years after ASCT remains considerable, but ASCT in this setting seems to be a good choice for AML patients with active disease. However, novel approaches are needed to reduce TRM and relapse in this set of patients
EFSA Panel on Dietetic Products, Nutrition, and Allergies (NDA); Scientific Opinion on the Tolerable Upper Intake Level of calcium
<p>Following a request from the European Commission, the Panel on Dietetic Products, Nutrition and Allergies was asked to re-evaluate the safety in use of calcium. The Panel was requested to consider if the Tolerable Upper Intake Level (UL) for calcium established by the SCF in 2003 (2,500 mg/day for adults, including pregnant and lactating women), which was based on different intervention studies of long duration in which total daily calcium intakes of 2,500 mg from both diet and supplements were tolerated without adverse effects, needed to be changed on the basis of new available evidence. A number of placebo controlled human intervention studies in adults published since then also showed that total daily calcium intakes of 2,500 mg from both diet and supplements are tolerated without adverse effects. The Panel considers that no relationship has been established between long-term calcium intakes from diet and supplements and increased risk of nephrolithiasis, cardiovascular disease or prostate cancer. No new data have become available which would require a revision of the UL for calcium for adults, including pregnant and lactating women, of 2,500 mg. No new data have become available which would allow the setting of a UL for infants, children or adolescents. Data from European populations indicate that intakes of calcium in high consumers among adult males can be close to the UL. Although available data do not allow the setting of a UL for infants, children or adolescents, no risk has been identified with highest current levels of calcium intake in these age groups.</p>
Palaeogenomic analysis of black rat (Rattus rattus) reveals multiple European introductions associated with human economic history
The distribution of the black rat (Rattus rattus) has been heavily influenced by its association with humans. The dispersal history of this non-native commensal rodent across Europe, however, remains poorly understood, and different introductions may have occurred during the Roman and medieval periods. Here, in order to reconstruct the population history of European black rats, we generated a de novo genome assembly of the black rat, 67 ancient black rat mitogenomes and 36 ancient nuclear genomes from sites spanning the 1st-17th centuries CE in Europe and North Africa. Analyses of mitochondrial DNA confirm that black rats were introduced into the Mediterranean and Europe from Southwest Asia. Genomic analyses of the ancient rats reveal a population turnover in temperate Europe between the 6th and 10th centuries CE, coincident with an archaeologically attested decline in the black rat population. The near disappearance and re-emergence of black rats in Europe may have been the result of the breakdown of the Roman Empire, the First Plague Pandemic, and/or post-Roman climatic cooling.Competing Interest StatementThe authors have declared no competing interest.- Results and Discussion -- The demographic history of Rattus rattus and its closely related species -- A global phylogeography of the black rat based on mitochondrial DNA -- Ancient genomes reveal the relationships of European black rats over space and time - Discussion - Method
Palaeogenomic analysis of black rat (Rattus rattus) reveals multiple European introductions associated with human economic history
The distribution of the black rat (Rattus rattus) has been heavily influenced by its association with humans. The dispersal history of this non-native commensal rodent across Europe, however, remains poorly understood, and different introductions may have occurred during the Roman and medieval periods. Here, in order to reconstruct the population history of European black rats, we first generate a de novo genome assembly of the black rat. We then sequence 67 ancient and three modern black rat mitogenomes, and 36 ancient and three modern nuclear genomes from archaeological sites spanning the 1st-17th centuries CE in Europe and North Africa. Analyses of our newly reported sequences, together with published mitochondrial DNA sequences, confirm that black rats were introduced into the Mediterranean and Europe from Southwest Asia. Genomic analyses of the ancient rats reveal a population turnover in temperate Europe between the 6th and 10th centuries CE, coincident with an archaeologically attested decline in the black rat population. The near disappearance and re-emergence of black rats in Europe may have been the result of the breakdown of the Roman Empire, the First Plague Pandemic, and/or post-Roman climatic cooling.Peer reviewe
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