1,474 research outputs found

    X-SAR: The X-band synthetic aperture radar on board the Space Shuttle

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    The X-band synthetic aperture radar (X-SAR) is the German/Italian contribution to the NASA/JPL Shuttle Radar Lab missions as part of the preparation for the Earth Observation System (EOS) program. The Shuttle Radar Lab is a combination of several radars: an L-band (1.2 GHz) and a C-band (5.3 GHz) multipolarization SAR known as SIR-C (Shuttle Imaging Radar); and an X-band (9.6 GHz) vertically polarized SAR which will be operated synchronously over the same target areas to deliver calibrated multifrequency and multipolarization SAR data at multiple incidence angles from space. A joint German/Italian project office at DARA (German Space Agency) is responsible for the management of the X-SAR project. The space hardware has been developed and manufactured under industrial contract by Dornier and Alenia Spazio. Besides supporting all the technical and scientific tasks, DLR, in cooperation with ASI (Agencia Spaziale Italiano) is responsible for mission operation, calibration, and high precision SAR processing. In addition, DLR developed an airborne X-band SAR to support the experimenters with campaigns to prepare for the missions. The main advantage of adding a shorter wavelength (3 cm) radar to the SIR-C radars is the X-band radar's weaker penetration into vegetation and soil and its high sensitivity to surface roughness and associated phenomena. The performance of each of the three radars is comparable with respect to radiometric and geometric resolution

    New-onset refractory status epilepticus due to autoimmune encephalitis after vaccination against SARS-CoV-2: First case report

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    BACKGROUND Vaccination against SARS-CoV-2 has been conducted frequently to limit the pandemic but may rarely be associated with postvaccinal autoimmune reactions or disorders. CASE PRESENTATION We present a 35-year-old woman who developed fever, skin rash, and headache 2 days after the second SARS-CoV-2 vaccination with BNT162b2 (Pfizer/Biontech). Eight days later, she developed behavioral changes and severe recurrent seizures that led to sedation and intubation. Cerebral magnetic resonance imaging showed swelling in the (para-) hippocampal region predominantly on the left hemisphere and bilateral subcortical subinsular FLAIR hyperintensities. Cerebrospinal fluid analysis revealed a lymphocytic pleocytosis of 7 cells/μl and normal protein and immunoglobulin parameters. Common causes of encephalitis or encephalopathy such as viral infections, autoimmune encephalitis with well-characterized autoantibodies, paraneoplastic diseases, and intoxications were ruled out. We made a diagnosis of new-onset refractory status epilepticus (NORSE) due to seronegative autoimmune encephalitis. The neurological deficits improved after combined antiepileptic therapy and immunomodulatory treatment including high-dose methylprednisolone and plasma exchange. CONCLUSIONS Although a causal relationship cannot be established, the onset of symptoms shortly after receiving the SARS-CoV-2 vaccine suggests a potential association between the vaccination and NORSE due to antibody-negative autoimmune encephalitis. After ruling out other etiologies, early immunomodulatory treatment may be considered in such cases

    Proton and anti-proton production in the forward region of d+Au collisions at RHIC from the color glass condensate

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    The power-law tail of high-pt pi^\pm spectra observed in forward d+Au collisions at RHIC can be attributed to the power-law decrease of the dipole forward scattering amplitude appearing in the color glass condensate (CGC) approach. Forward particle production probes the small-x gluon distribution of the target nucleus where its anomalous dimension is rather flat (gamma = 0.6 \sim 0.8) for moderately high pt (\lsim 5 GeV), and where the leading-twist DGLAP approximation is not valid. In the same framework, we examine p and \bar{p} production using baryon fragmentation functions parameterized in the Lund fragmentation scheme. This provides a good description of the forward \bar{p} spectrum while it underestimates the p data by as much as a factor of 2 \sim 3 at pt \lsim 4 GeV. Part of this anomalous baryon excess can be attributed to surviving constituent diquarks from the deuteron projectile. Thus, the contribution from diquark scattering may play an essential role for forward baryon formation.Comment: 20 pages, 5 figure

    Quantum degrees of polarization

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    We discuss different proposals for the degree of polarization of quantum fields. The simplest approach, namely making a direct analogy with the classical description via the Stokes operators, is known to produce unsatisfactory results. Still, we argue that these operators and their properties should be basic for any measure of polarization. We compare alternative quantum degrees and put forth that they order various states differently. This is to be expected, since, despite being rooted in the Stokes operators, each of these measures only captures certain characteristics. Therefore, it is likely that several quantum degrees of polarization will coexist, each one having its specific domain of usefulness.Comment: 9 pages, 3 figures. v2: Minor corrections and improvement

    Initial Conditions and Global Event Properties from Color Glass Condensate

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    Perturbative unitarization from non-linear effects is thought to deplete the gluon density for transverse momenta below the saturation scale. Such effects also modify the distribution of gluons produced in heavy-ion collisions in transverse impact parameter space. I discuss some of the consequences for the initial conditions for hydrodynamic models of heavy-ion collisions and for hard ``tomographic'' probes. Also, I stress the importance of realistic modelling of the fluctuations of the valence sources for the small-x fields in the impact parameter plane. Such models can now be combined with solutions of running-coupling Balitsky-Kovchegov evolution to obtain controlled predictions for initial conditions at the LHC.Comment: 7 pages, 2 figures; to appear in the proceedings of the RIKEN BNL Research Center Workshop on "Saturation, the Color Glass Condensate and Glasma: What Have we Learned from RHIC?", May 10-12, 2010; to be published in Nucl. Phys.

    Feasibility of endometrial sampling by vaginal tampons in women with Lynch syndrome

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    Background: Endometrial sampling for the surveillance of women with Lynch syndrome is an invasive and painful procedure. The aim of this study was to evaluate the feasibility of a less invasive procedure of collecting vital cells by vaginal tampons. Methods: This was a prospective feasibility study of women scheduled to undergo annual gynecological surveillance, including endometrial sampling. We included consecutive asymptomatic women with Lynch syndrome or first-degree relatives and asked them to insert a vaginal tampon 2-4 h before attending their outpatient appointment. Feasibility was evaluated by the following metrics: Patient acceptance, pain intensity of each procedure (assessed by visual analog scale; range 0-10), and the presence of vital cells obtained by tampon-based or endometrial sampling methods. Two pathologists independently evaluated all samples. Results: In total, 25 of 32 approached women completed the tampon-based procedure, with 23 of these subsequently undergoing invasive endometrial sampling. The median visual analog scale scores for tampon use and invasive endometrial sampling were 0 (range, 0-10) and 5.5 (range, 1-10) (p < 0.001). None of the tampon samples analyzed by cytology showed endometrial cells, but they did contain vital squamous cells and granulocytes. By contrast, 18 (78%) of the invasive endometrial samples contained enough endometrial tissue for analysis. No endometrial abnormalities were found by endometrial sampling. Conclusions: Tampon-based endometrial surveillance was a well-accepted and non-painful procedure, and although tampons contained vital cells, they did not provide endometrial cells. However, this study was limited to asymptomatic women with Lynch syndrome (no endometrial pathology), indicating that research is needed to evaluate whether the tampon method has any utility for endometrial surveillance in women with Lynch syndrome

    Attachment representations and autonomic regulation in maltreating and nonmaltreating mothers.

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    This study assessed attachment representation and attachment-related autonomic regulation in a sample of 38 maltreating and 35 nonmaltreating mothers. Mothers' state of mind regarding attachment was measured using the Adult Attachment Interview. They further watched an attachment-based comfort paradigm, during which we measured skin conductance and vagal tone. More maltreating mothers (42%) than nonmaltreating mothers (17%) had an unresolved/disoriented attachment classification. Attachment representation was related to physiology during the comfort paradigm: an unresolved state of mind and a nonautonomous classification were associated with a decrease in skin conductance during the comfort paradigm, specifically during the responsive caregiver scenario. However, physiology did not differ between maltreating and nonmaltreating mothers. The decrease in skin conductance of unresolved mothers during the comfort paradigm might be indicative of a deactivating response, which is congruent with the dissociative nature of the unresolved state of mind. The results point to the potential utility of interventions focused on attachment representations for maltreating mothers.The study was supported by Yulius mental health clinic, the Netherlands Organization for Scientific Research (MHvIJ: NWO SPINOZA prize; MJBK: VICI grant; LRAA: VIDI grant), and the Wellcome Trust (WT103343MA).This is the author accepted manuscript. The final version is available from Cambridge University Press via https://doi.org/10.1017/S095457941600103

    COMPRENDO: Focus and approach

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    Tens of thousands of man-made chemicals are in regular use and discharged into the environment. Many of them are known to interfere with the hormonal systems in humans and wildlife. Given the complexity of endocrine systems, there are many ways in which endocrine-disrupting chemicals (EDCs) can affect the body’s signaling system, and this makes unraveling the mechanisms of action of these chemicals difficult. A major concern is that some of these EDCs appear to be biologically active at extremely low concentrations. There is growing evidence to indicate that the guiding principle of traditional toxicology that “the dose makes the poison” may not always be the case because some EDCs do not induce the classical dose–response relationships. The European Union project COMPRENDO (Comparative Research on Endocrine Disrupters—Phylogenetic Approach and Common Principles focussing on Androgenic/Antiandrogenic Compounds) therefore aims to develop an understanding of potential health problems posed by androgenic and antiandrogenic compounds (AACs) to wildlife and humans by focusing on the commonalities and differences in responses to AACs across the animal kingdom (from invertebrates to vertebrates)

    e-Skills: The International dimension and the Impact of Globalisation - Final Report 2014

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    In today’s increasingly knowledge-based economies, new information and communication technologies are a key engine for growth fuelled by the innovative ideas of highly - skilled workers. However, obtaining adequate quantities of employees with the necessary e-skills is a challenge. This is a growing international problem with many countries having an insufficient numbers of workers with the right e-Skills. For example: Australia: “Even though there’s 10,000 jobs a year created in IT, there are only 4500 students studying IT at university, and not all of them graduate” (Talevski and Osman, 2013). Brazil: “Brazil’s ICT sector requires about 78,000 [new] people by 2014. But, according to Brasscom, there are only 33,000 youths studying ICT related courses in the country” (Ammachchi, 2012). Canada: “It is widely acknowledged that it is becoming inc reasingly difficult to recruit for a variety of critical ICT occupations –from entry level to seasoned” (Ticoll and Nordicity, 2012). Europe: It is estimated that there will be an e-skills gap within Europe of up to 900,000 (main forecast scenario) ICT pr actitioners by 2020” (Empirica, 2014). Japan: It is reported that 80% of IT and user companies report an e-skills shortage (IPA, IT HR White Paper, 2013) United States: “Unlike the fiscal cliff where we are still peering over the edge, we careened over the “IT Skills Cliff” some years ago as our economy digitalized, mobilized and further “technologized”, and our IT skilled labour supply failed to keep up” (Miano, 2013)
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