The search for dark matter, the missing mass of the Universe, is one of the most active fields of study within particle physics. The XENON1T experiment recently observed a 3.5σ excess potentially ...consistent with dark matter, or with solar axions. Here, we will use the Noble Element Simulation Technique (NEST) software to simulate the XENON1T detector, reproducing the excess. We utilize different detector efficiency and energy reconstruction models, but they primarily impact sub-keV energies and cannot explain the XENON1T excess. However, using NEST, we can reproduce their excess in multiple, unique ways, most easily via the addition of 31 ± 11 37Ar decays. Furthermore, this results in new, modified background models, reducing the significance of the excess to ≤ 2.2 σ at least using non-Profile Likelihood Ratio (PLR) methods. This is independent confirmation that the excess is a real effect, but potentially explicable by known physics. Many cross-checks of our 37Ar hypothesis are presented.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
This paper considers robust filtering for a nominal Gaussian state-space model, when a relative entropy tolerance is applied to each time increment of a dynamical model. The problem is formulated as ...a dynamic minimax game where the maximizer adopts a myopic strategy. This game is shown to admit a saddle point whose structure is characterized by applying and extending results presented earlier in "Robust least-squares estimation with a relative entropy constraint" (B. C. Levy and R. Nikoukhah, IEEE Trans. Inf. Theory, vol. 50, no. 1, 89-104, Jan. 2004) for static least-squares estimation. The resulting minimax filter takes the form of a risk-sensitive filter with a time varying risk sensitivity parameter, which depends on the tolerance bound applied to the model dynamics and observations at the corresponding time index. The least-favorable model is constructed and used to evaluate the performance of alternative filters. Simulations comparing the proposed risk-sensitive filter to a standard Kalman filter show a significant performance advantage when applied to the least-favorable model, and only a small performance loss for the nominal model.
More than 2 decades ago, aerosol remote sensing underwent a revolution with the launch of the Terra and Aqua satellites. Advancement continued via additional launches carrying new passive and active ...sensors. Capable of retrieving parameters characterizing aerosol loading, rudimentary particle properties and in some cases aerosol layer height, the satellite view of Earth's aerosol system came into focus. The modeling communities have made similar advances. Now the efforts have continued long enough that we can see developing trends in both the remote sensing and modeling communities, allowing us to speculate about the future and how the community will approach aerosol remote sensing 20 years from now. We anticipate technology that will replace today's standard multi-wavelength radiometers with hyperspectral and/or polarimetry, all viewing at multiple angles. These will be supported by advanced active sensors with the ability to measure profiles of aerosol extinction in addition to backscatter. The result will be greater insight into aerosol particle properties. Algorithms will move from being primarily physically based to include an increasing degree of machine-learning methods, but physically based techniques will not go extinct. However, the practice of applying algorithms to a single sensor will be in decline. Retrieval algorithms will encompass multiple sensors and all available ground measurements in a unifying framework, and these inverted products will be ingested directly into assimilation systems, becoming “cyborgs”: half observations, half model. In 20 years we will see a true democratization in space with nations large and small, private organizations, and commercial entities of all sizes launching space sensors. With this increasing number of data and aerosol products available, there will be a lot of bad data. User communities will organize to set standards, and the large national space agencies will lead the effort to maintain quality by deploying and maintaining validation ground networks and focused field experiments. Through it all, interest will remain high in the global aerosol system and how that system affects climate, clouds, precipitation and dynamics, air quality, the environment and public health, transport of pathogens and fertilization of ecosystems, and how these processes are adapting to a changing climate.
We present 0 15 (∼2.5 pc) resolution ALMA CO(3-2) observations of the starbursting center in NGC 253. Together with archival ALMA CO(1-0) and CO(2-1) data, we decompose the emission into disk and ...nondisk components. We find ∼7%-16% of the CO luminosity to be associated with the nondisk component (1.2-4.2 × 107 K km s−1 pc2). The total molecular gas mass in the center of NGC 253 is ∼3.6 × 108 M with ∼0.5 × 108 M (∼15%) in the nondisk component. These measurements are consistent across independent mass estimates through three CO transitions. The high-resolution CO(3-2) observations allow us to identify the molecular outflow within the nondisk gas. Using a starburst conversion factor, we estimate the deprojected molecular mass outflow rate, kinetic energy, and momentum in the starburst of NGC 253. The deprojected molecular mass outflow rate is in the range of ∼14-39 M yr−1 with an uncertainty of 0.4 dex. The large spread arises due to different interpretations of the kinematics of the observed gas while the errors are due to unknown geometry. The majority of this outflow rate is contributed by distinct outflows perpendicular to the disk, with a significant contribution by diffuse molecular gas. This results in a mass-loading factor in the range ∼ 8−20 for gas ejected out to ∼300 pc. We find the kinetic energy of the outflow to be ∼2.5-4.5 × 1054 erg and a typical error of ∼0.8 dex, which is ∼0.1% of the total or ∼8% of the kinetic energy supplied by the starburst. The outflow momentum is 4.8-8.7 × 108 M km s−1 (∼0.5 dex error) or ∼2.5%-4% of the kinetic momentum released into the ISM by the feedback. The unknown outflow geometry and launching sites are the primary sources of uncertainty in this study.
Objectives The aim of this study was to conduct an initial clinical evaluation of the new HeartWare Ventricular Assist System (HeartWare, Inc., Framingham, Massachusetts) in a multicenter, ...prospective, nonrandomized single-arm clinical trial. Background Heart failure is a worldwide epidemic. The effectiveness of heart transplantation and medical therapy is limited, resulting in the emergence of mechanical circulatory support as a primary treatment for end-stage heart disease. Left ventricular assist devices that use rotary pumps are small and durable, which might reduce morbidity and mortality during support. Methods Fifty heart transplant candidates with New York Heart Association functional class IV symptoms were supported at 5 international centers by the HeartWare System for 180 days, until heart transplant, myocardial recovery and device explant, or death. Patients who continue to be supported have been followed for a minimum of 2 years. Results Of the 50 patients, 20 (40%) received transplants, 4 (8%) had the pump explanted after myocardial recovery, and 17 (34%) continue support at 2 years. Nine (18%) patients died during support from sepsis (n = 3), multiple organ failure (n = 3), or hemorrhagic stroke (n = 3). The actual survival at 6, 12, and 24 months was 90%, 84%, and 79%, respectively. In the survivors, measures of quality of life showed a significant improvement over baseline values. Significant improvements were found for recognition memory at 3 months after implant (p = 0.006). The most frequent adverse events were infection and bleeding. Conclusions Patients with end-stage heart failure can be safely and effectively supported by the HeartWare Ventricular Assist System with improved quality of life and neurocognitive function.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The MODerate resolution Imaging Spectroradiometer (MODIS) instruments, aboard the two Earth Observing System (EOS) satellites Terra and Aqua, provide aerosol information with nearly daily global ...coverage at moderate spatial resolution (10 and 3 km). Almost 15 years of aerosol data records are now available from MODIS that can be used for various climate and air-quality applications. However, the application of MODIS aerosol products for air-quality concerns is limited by a reduction in retrieval accuracy over urban surfaces. This is largely because the urban surface reflectance behaves differently than that assumed for natural surfaces. In this study, we address the inaccuracies produced by the MODIS Dark Target (MDT) algorithm aerosol optical depth (AOD) retrievals over urban areas and suggest improvements by modifying the surface reflectance scheme in the algorithm. By integrating MODIS Land Surface Reflectance and Land Cover Type information into the aerosol surface parameterization scheme for urban areas, much of the issues associated with the standard algorithm have been mitigated for our test region, the continental United States (CONUS). The new surface scheme takes into account the change in underlying surface type and is only applied for MODIS pixels with urban percentage (UP) larger than 20 %. Over the urban areas where the new scheme has been applied (UP > 20 %), the number of AOD retrievals falling within expected error (EE %) has increased by 20 %, and the strong positive bias against ground-based sun photometry has been eliminated. However, we note that the new retrieval introduces a small negative bias for AOD values less than 0.1 due to the ultra-sensitivity of the AOD retrieval to the surface parameterization under low atmospheric aerosol loadings. Global application of the new urban surface parameterization appears promising, but further research and analysis are required before global implementation.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Abstract In this work we demonstrate that Dark Matter (DM) evaporation severely hinders the effectiveness of exoplanets and Brown Dwarfs as sub-GeV DM probes. Moreover, we find useful analytic closed ...form approximations for DM capture rates for arbitrary astrophysical objects, valid in four distinct regions in the σ - m X parameter space. As expected, in one of those regions the Dark Matter capture saturates to its geometric limit, i.e. the entire flux crossing an object. As a consequence of this region, which for many objects falls within the parameter space not excluded by direct detection experiments, we point out the existence of a DM parameter dependent critical temperature ( T crit ), above which astrophysical objects lose any sensitivity as Dark Matter probes. For instance, Jupiters at the Galactic Center have a T crit ranging from 700 K (for a 3 M J Jupiter) to 950 K (for 14 M J ). This limitation is rarely (if ever) considered in the previous literature of indirect Dark Matter detection based on observable signatures of captured Dark Matter inside celestial bodies.
We present a comparative study of molecular and ionized gas kinematics in nearby galaxies. These results are based on observations from the EDGE survey, which measured spatially resolved 12CO(J = ...1-0) in 126 nearby galaxies. Every galaxy in EDGE has corresponding resolved ionized gas measurements from CALIFA. Using a sub-sample of 17 rotation-dominated, star-forming galaxies where precise molecular gas rotation curves could be extracted, we derive CO and H rotation curves using the same geometric parameters out to 1 Re. We find that ∼75% of our sample galaxies have smaller ionized gas rotation velocities than the molecular gas in the outer part of the rotation curve. In no case is the molecular gas rotation velocity measurably lower than that of the ionized gas. We suggest that the lower ionized gas rotation velocity can be attributed to a significant contribution from extraplanar diffuse ionized gas in a thick, turbulence-supported disk. Using observations of the Hγ transition, also available from CALIFA, we measure ionized gas velocity dispersions and find that these galaxies have sufficiently large velocity dispersions to support a thick ionized gas disk. Kinematic simulations show that a thick disk with a vertical rotation velocity gradient can reproduce the observed differences between the CO and H rotation velocities. Observed line ratios tracing diffuse ionized gas are elevated compared to typical values in the midplane of the Milky Way. In galaxies affected by this phenomenon, dynamical masses measured using ionized gas rotation curves will be systematically underestimated.
Le streptocoque du groupe A (SGA) est la première bactérie retrouvée en cas d’angine chez l’enfant. Le diagnostic d’angine à SGA ne peut être fait par le seul examen clinique. Des tests de diagnostic ...rapide (TDR) permettent de détecter le SGA en quelques minutes grâce à des techniques immunologiques. En comparaison à la culture de prélèvement de gorge, la spécificité du TDR est suffisante (environ 95 %) pour qu’un résultat positif justifie la prescription d’un antibiotique. La valeur prédictive négative du TDR (environ 95 %) est elle aussi suffisante pour écarter la présence du SGA en cas de résultat négatif. Parmi les nombreux facteurs faisant varier la sensibilité du TDR, l’expérience de la personne réalisant le test et la qualité du prélèvement de gorge sont particulièrement déterminantes. Les règles de décision clinique disponibles ne sont pas suffisamment discriminantes pour permettre de sélectionner les enfants chez qui un TDR doit être réalisé ou une antibiothérapie débutée. La mise en place d’une stratégie d’utilisation du TDR permet de diminuer en moyenne de 30 % la prescription d’antibiotiques. Les recommandations françaises actuelles qui sont de réaliser un TDR de manière systématique chez l’enfant de plus de 3 ans sans avoir à confirmer les TDR négatifs par une mise en culture sont donc pertinentes.
Group A streptococcus (GAS) is the most frequently identified bacterium in children with acute pharyngitis. Clinical signs and symptoms cannot distinguish accurately between viral and GAS pharyngitis. Rapid antigen detection tests (RADTs) can identify GAS by an immunologic reaction within a few minutes. Compared to throat culture, most RADTs have a high specificity (around 95 %), allowing antibiotic prescribing on the basis of a positive RADT result. Similarly, the negative predictive value of RADTs seems sufficiently high (around 95 %) to ensure against the presence of GAS in case of a negative RADT result. Among several factors affecting RADT sensitivity, the training and expertise of the person performing the test and the quality of the throat swab specimen seem to be key determinants. Available evidence suggests that clinical prediction rules for the triage of children who should undergo GAS testing are not sufficiently accurate. Implementing RADTs into clinical practice has an important impact on antibiotic prescription rates, for a reduction of about 30 %. French guidelines that recommend using RADTs in all children above 3 years of age presenting with pharyngitis without backup culture of negative tests seem relevant in this context.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Les méningites dues au streptocoque du groupe A (SGA) chez l’enfant sont rares. Le but de cette étude est d’analyser les éléments cliniques, biologiques et évolutifs des méningites à SGA rapportées ...dans l’Observatoire national des méningites bactériennes de l’enfant.
Entre janvier 2001 et décembre 2012, 4 564 méningites bactériennes ont été rapportées, dont 35 (0,7 %) étaient à SGA. L’âge médian des enfants était de 5,6 ans. L’histoire clinique retrouvait fréquemment une infection communautaire précédant la méningite. En dehors de l’identification de l’espèce bactérienne, aucune caractéristique clinique ou biologique ne permettait de distinguer ces méningites à SGA d’autres bactéries en particulier du pneumocoque. Le taux de mortalité était de 8 %.
Group A streptococcal (GAS) meningitis in children are rare. The aim of this study was to analyze the clinical, biological and outcome data on GAS meningitis recorded in the Bacterial Meningitis (BM) French Surveillance Network (GPIP/ACTIV).
From 2001 through 2012, 4,564 children suffering from proven bacterial meningitis were recorded in the data base. Among them, 0.7 % were GAS infections. The median age was 5.6 years. A history of community acquired infection before the onset of GAS meningitis was frequent. Apart from the identification of the bacterial species, GAS meningitis were clinically and biologically indistinguishable from meningitis caused by other pathogens notably S. pneumoniae. Case fatality rate was 8 %.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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