15,192 research outputs found

    Satellite observations of reconnection between emerging and pre-existing small-scale magnetic fields

    Get PDF
    We report multi-wavelength ultraviolet observations taken with the IRIS satellite, concerning the emergence phase in the upper chromosphere and transition region of an emerging flux region (EFR) embedded in the unipolar plage of active region NOAA 12529. The photospheric configuration of the EFR is analyzed in detail benefitting from measurements taken with the spectropolarimeter aboard the Hinode satellite, when the EFR was fully developed. In addition, these data are complemented by full-disk, simultaneous observations of the SDO satellite, relevant to the photosphere and the corona. In the photosphere, magnetic flux emergence signatures are recognized in the fuzzy granulation, with dark alignments between the emerging polarities, cospatial with highly inclined fields. In the upper atmospheric layers, we identify recurrent brightenings that resemble UV bursts, with counterparts in all coronal passbands. These occur at the edges of the EFR and in the region of the arch filament system (AFS) cospatial to the EFR. Jet activity is also found at chromospheric and coronal levels, near the AFS and the observed brightness enhancement sites. The analysis of the IRIS line profiles reveals the heating of dense plasma in the low solar atmosphere and the driving of bi-directional high-velocity flows with speeds up to 100 km/s at the same locations. Furthermore, we detect a correlation between the Doppler velocity and line width of the Si IV 1394 and 1402 \AA{} line profiles in the UV burst pixels and their skewness. Comparing these findings with previous observations and numerical models, we suggest evidence of several long-lasting, small-scale magnetic reconnection episodes between the emerging bipole and the ambient field. This process leads to the cancellation of a pre-existing photospheric flux concentration of the plage with the opposite polarity flux patch of the EFR. [...]Comment: 4 pages, 2 figures, to be published in "Nuovo Cimento C" as proceeding of the Third Meeting of the Italian Solar and Heliospheric Communit

    The Americanization of International Litigation

    Get PDF
    Published in cooperation with the American Bar Association Section of Dispute Resolutio

    2D-3D registration of CT vertebra volume to fluoroscopy projection: A calibration model assessment (doi:10.1155/2010/806094)

    Get PDF
    This study extends a previous research concerning intervertebral motion registration by means of 2D dynamic fluoroscopy to obtain a more comprehensive 3D description of vertebral kinematics. The problem of estimating the 3D rigid pose of a CT volume of a vertebra from its 2D X-ray fluoroscopy projection is addressed. 2D-3D registration is obtained maximising a measure of similarity between Digitally Reconstructed Radiographs (obtained from the CT volume) and real fluoroscopic projection. X-ray energy correction was performed. To assess the method a calibration model was realised a sheep dry vertebra was rigidly fixed to a frame of reference including metallic markers. Accurate measurement of 3D orientation was obtained via single-camera calibration of the markers and held as true 3D vertebra position; then, vertebra 3D pose was estimated and results compared. Error analysis revealed accuracy of the order of 0.1 degree for the rotation angles of about 1?mm for displacements parallel to the fluoroscopic plane, and of order of 10?mm for the orthogonal displacement.<br/

    Assessing the impact of seasonal-rainfall anomalies on catchment-scale water balance components

    Get PDF
    Abstract. Although water balance components at the catchment scale are strongly related to annual rainfall, the availability of water resources in Mediterranean catchments also depends on rainfall seasonality. Observed seasonal anomalies in historical records are fairly episodic, but an increase in their frequency might exacerbate water deficit or water excess if the rainy season shortens or extends its duration, e.g., due to climate change. This study evaluates the sensitivity of water yield, evapotranspiration, and groundwater recharge to changes in rainfall seasonality by using the Soil Water Assessment Tool (SWAT) model applied to the upper Alento River catchment (UARC) in southern Italy, where a long time series of daily rainfall is available from 1920 to 2018. We compare two distinct approaches: (i) a "static" approach, where three seasonal features (namely rainy, dry, and transition fixed-duration 4-month seasons) are identified through the standardized precipitation index (SPI) and (ii) a "dynamic" approach based on a stochastic framework, where the duration of two seasons (rainy and dry seasons) varies from year to year according to a probability distribution. Seasonal anomalies occur when the transition season is replaced by the rainy or dry season in the first approach and when season duration occurs in the tails of its normal distribution in the second approach. Results are presented within a probabilistic framework. We also show that the Budyko curve is sensitive to the rainfall seasonality regime in UARC by questioning the implicit assumption of a temporal steady state between annual average dryness and the evaporative index. Although the duration of the rainy season does not exert a major control on water balance, we were able to identify season-dependent regression equations linking water yield to the dryness index in the rainy season

    Spin-orbital coupling in a triplet superconductor-ferromagnet junction

    Full text link
    We study a novel type of coupling between spin and orbital degrees of freedom which appears at triplet superconductor-ferromagnet interfaces. Using a self-consistent spatially-dependent mean-field theory, we show that increasing the angle between the ferromagnetic moment and the triplet vector order parameter enhances or suppresses the p-wave gap close to the interface, according as the gap antinodes are parallel or perpendicular to the boundary, respectively. The associated change in condensation energy establishes an orbitally-dependent preferred orientation for the magnetization. When both gap components are present, as in a chiral superconductor, we observe a first-order transition between different moment orientations as a function of the exchange field strength.Comment: 5 pages, 4 figures and Supplemental Material (3 pages

    Influence of Cleft Lip and Palate on Oral Health-Related Quality of Life in Northern Italy: Exploring Both the Children’s and Caregivers’ Perspectives

    Get PDF
    The aim of this cross-sectional study was to examine whether parents/caregivers’ perceptions of oral health-related quality of life (OHRQoL) differ from that of their cleft children, exploring the impact of demographic variables and cleft type on their agreement. Fifty-three primary and secondary schoolchildren, with non-syndromic orofacial cleft, and their parents answered the Child Oral Health Impact Profile (COHIP) questionnaire. Concordance between caregivers’ and children’s reports was low to moderate. Parents/caregivers had worse perceptions of OHRQoL compared to that of their children, peer interaction and functional well-being domains being statistically significantly different (p = 0.033 and p = 0.005, respectively). Cleft type, gender and parents’ country of origin seemed to be potential contributing factors of disagreement. Parents overestimated the impact of unilateral (p = 0.047) and bilateral cleft lip and palate (p = 0.021) on OHRQoL, and they rated more poorly than their male children did. Italian parents were more concerned about the functional well-being of their children (p = 0.014), and foreign parents about peer interaction (p = 0.010) and school environment (p = 0.012) dimensions. These findings suggest that parental assessment of OHRQoL cannot replace that of school-aged children, but they are complementary as they cover different, but equally relevant perspectives

    Evaluation of biodentine in pulpotomies of primary teeth with different stages of root resorption using a novel composite outcome score

    Get PDF
    This study aimed to assess the success of pulpotomy in primary molars using Biodentine, new-developed tri-calcium, di-calcium-based silicate cement, at 6 and 12 months. The hypothesis was that stages of root resorption could influence the treatment success. A novel composite score was used based on five clinical and radiographic outcomes: soft-tissue pathology, pain to percussion, pathologic mobility, radiolucency and pathologic root resorption. Patients’ compliance and intraoperative pain experience were recorded using the Frankl scale and the Wong–Baker scale. A total of 22 primary molars, 9 in stage S (stability) and 13 in stage R (resorption) were submitted to pulpotomy using Biodentine and restored with composite resin. The success rate was 92.3% in the R group compared to 100% in the S group at both 6 and 12 months (p = 0.850). There was no statistically significant effect of type of molar, tooth position and type of carious lesions on the composite outcome (all p &gt; 0.05). Overall, 73% of the children experienced no or mild/moderate pain and 77% had a cooperative attitude. Children younger than 7 years old experienced more pain (p = 0.04). Biodentine is a promising biomaterial for pulpotomy of primary teeth regardless of the stage of root resorption

    Relaxation to equilibrium driven via indirect control in Markovian dynamics

    Full text link
    We characterize to what extent it is possible to modify the stationary states of a quantum dynamical semigroup, that describes the irreversible evolution of a two-level system, by means of an auxiliary two-level system. We consider systems that can be initially entangled or uncorrelated. We find that the indirect control of the stationary states is possible, even if there are not initial correlations, under suitable conditions on the dynamical parameters characterizing the evolution of the joint system.Comment: revtex4, 7 page
    corecore