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High-energy tau neutrinos are rarely produced in atmospheric cosmic-ray showers or at cosmic particle accelerators, but are expected to emerge during neutrino propagation over cosmic distances due to flavor mixing. When high energy tau neutrinos interact inside the IceCube detector, two spatially separated energy depositions may be resolved, the first from the charged current interaction and the second from the tau lepton decay. We report a novel analysis of 7.5 years of IceCube data that identifies two candidate tau neutrinos among the 60 "High-Energy Starting Events" (HESE) collected during that period. The HESE sample offers high purity, all-sky sensitivity, and distinct observational signatures for each neutrino flavor, enabling a new measurement of the flavor composition. The measured astrophysical neutrino flavor composition is consistent with expectations, and an astrophysical tau neutrino flux is indicated at 2.8 σ significance. [ABSTRACT FROM AUTHOR]

The reconstruction of event-level information, such as the direction or energy of a neutrino interacting in IceCube DeepCore, is a crucial ingredient to many physics analyses. Algorithms to extract this high level information from the detector's raw data have been successfully developed and used for high energy events. In this work, we address unique challenges associated with the reconstruction of lower energy events in the range of a few to hundreds of GeV and present two separate, state-of-the-art algorithms. One algorithm focuses on the fast directional reconstruction of events based on unscattered light. The second algorithm is a likelihood-based multipurpose reconstruction offering superior resolutions, at the expense of larger computational cost. [ABSTRACT FROM AUTHOR]

The observation of electromagnetic radiation from radio to γ-ray wavelengths has provided a wealth of information about the Universe. However, at PeV (1015 eV) energies and above, most of the Universe is impenetrable to photons. New messengers, namely cosmic neutrinos, are needed to explore the most extreme environments of the Universe where black holes, neutron stars, and stellar explosions transform gravitational energy into non-thermal cosmic rays. These energetic particles have millions of times higher energies than those produced in the most powerful particle accelerators on Earth. As neutrinos can escape from regions otherwise opaque to radiation, they allow an unique view deep into exploding stars and the vicinity of the event horizons of black holes. The discovery of cosmic neutrinos with IceCube has opened this new window on the Universe. IceCube has been successful in finding first evidence for cosmic particle acceleration in the jet of an active galactic nucleus. Yet, ultimately, its sensitivity is too limited to detect even the brightest neutrino sources with high significance, or to detect populations of less luminous sources. In this white paper, we present an overview of a next-generation instrument, IceCube-Gen2, which will sharpen our understanding of the processes and environments that govern the Universe at the highest energies. IceCube-Gen2 is designed to: (a) Resolve the high-energy neutrino sky from TeV to EeV energies (b) Investigate cosmic particle acceleration through multi-messenger observations (c) Reveal the sources and propagation of the highest energy particles in the Universe (d) Probe fundamental physics with high-energy neutrinos IceCube-Gen2 will enhance the existing IceCube detector at the South Pole. It will increase the annual rate of observed cosmic neutrinos by a factor of ten compared to IceCube, and will be able to detect sources five times fainter than its predecessor. Furthermore, through the addition of a radio array, IceCube-Gen2 will extend the energy range by several orders of magnitude compared to IceCube. Construction will take 8 years and cost about $350M. The goal is to have IceCube-Gen2 fully operational by 2033. IceCube-Gen2 will play an essential role in shaping the new era of multi-messenger astronomy, fundamentally advancing our knowledge of the high-energy Universe. This challenging mission can be fully addressed only through the combination of the information from the neutrino, electromagnetic, and gravitational wave emission of high-energy sources, in concert with the new survey instruments across the electromagnetic spectrum and gravitational wave detectors which will be available in the coming years. [ABSTRACT FROM AUTHOR]

High-energy neutrinos are unique messengers of the high-energy universe, tracing the processes of cosmic ray acceleration. This paper presents analyses focusing on time-dependent neutrino point-source searches. A scan of the whole sky, making no prior assumption about source candidates, is performed, looking for a space and time clustering of high-energy neutrinos in data collected by the IceCube Neutrino Observatory between 2012 and 2017. No statistically significant evidence for a time-dependent neutrino signal is found with this search during this period, as all results are consistent with the background expectation. Within this study period, the blazar 3C 279, showed strong variability, inducing a very prominent gamma-ray flare observed in 2015 June. This event motivated a dedicated study of the blazar, which consists of searching for a time-dependent neutrino signal correlated with the gamma-ray emission. No evidence for a time-dependent signal is found. Hence, an upper limit on the neutrino fluence is derived, allowing us to constrain a hadronic emission model. [ABSTRACT FROM AUTHOR]

In multi-messenger astronomy, rapid investigation of interesting transients is imperative. As an observatory with a 4π steradian field of view, and ∼99% uptime, the IceCube Neutrino Observatory is a unique facility to follow up transients, as well as to provide valuable insights for other observatories and inform their observational decisions. Since 2016, IceCube has been using low-latency data to rapidly respond to interesting astrophysical events reported by the multi-messenger observational community. Here, we describe the pipeline used to perform these followup analyses, and provide a summary of the 58 analyses performed as of July 2020. We find no significant signal in the first 58 analyses performed. The pipeline has helped inform various electromagnetic observation strategies, and has constrained neutrino emission from potential hadronic cosmic accelerators. [ABSTRACT FROM AUTHOR]

The Glashow resonance describes the resonant formation of a W− boson during the interaction of a high-energy electron antineutrino with an electron1, peaking at an antineutrino energy of 6.3 petaelectronvolts (PeV) in the rest frame of the electron. Whereas this energy scale is out of reach for currently operating and future planned particle accelerators, natural astrophysical phenomena are expected to produce antineutrinos with energies beyond the PeV scale. Here we report the detection by the IceCube neutrino observatory of a cascade of high-energy particles (a particle shower) consistent with being created at the Glashow resonance. A shower with an energy of 6.05 ± 0.72 PeV (determined from Cherenkov radiation in the Antarctic Ice Sheet) was measured. Features consistent with the production of secondary muons in the particle shower indicate the hadronic decay of a resonant W− boson, confirm that the source is astrophysical and provide improved directional localization. The evidence of the Glashow resonance suggests the presence of electron antineutrinos in the astrophysical flux, while also providing further validation of the standard model of particle physics. Its unique signature indicates a method of distinguishing neutrinos from antineutrinos, thus providing a way to identify astronomical accelerators that produce neutrinos via hadronuclear or photohadronic interactions, with or without strong magnetic fields. As such, knowledge of both the flavour (that is, electron, muon or tau neutrinos) and charge (neutrino or antineutrino) will facilitate the advancement of neutrino astronomy.A particle shower detected by the IceCube Neutrino Observatory at the very high energy of the Glashow resonance demonstrates its potential for the study of high-energy particle physics and astrophysics. [ABSTRACT FROM AUTHOR]

Pulsar wind nebulae (PWNe) are the main gamma-ray emitters in the Galactic plane. They are diffuse nebulae that emit nonthermal radiation. Pulsar winds, relativistic magnetized outflows from the central star, shocked in the ambient medium produce a multiwavelength emission from the radio through gamma-rays. Although the leptonic scenario is able to explain most PWNe emission, a hadronic contribution cannot be excluded. A possible hadronic contribution to the high-energy gamma-ray emission inevitably leads to the production of neutrinos. Using 9.5 yr of all-sky IceCube data, we report results from a stacking analysis to search for neutrino emission from 35 PWNe that are high-energy gamma-ray emitters. In the absence of any significant correlation, we set upper limits on the total neutrino emission from those PWNe and constraints on hadronic spectral components. [ABSTRACT FROM AUTHOR]

The presence of a population of point sources in a data set modifies the underlying neutrino-count statistics from the Poisson distribution. This deviation can be exactly quantified using the non-Poissonian template fitting technique, and in this work we present the first application of this approach to the IceCube high-energy neutrino data set. Using this method, we search in 7 yr of IceCube data for point-source populations correlated with the disk of the Milky Way, the Fermi bubbles, the Schlegel, Finkbeiner, and Davis dust map, or with the isotropic extragalactic sky. No evidence for such a population is found in the data using this technique, and in the absence of a signal, we establish constraints on population models with source-count distribution functions that can be described by a power law with a single break. The derived limits can be interpreted in the context of many possible source classes. In order to enhance the flexibility of the results, we publish the full posterior from our analysis, which can be used to establish limits on specific population models that would contribute to the observed IceCube neutrino flux. [ABSTRACT FROM AUTHOR]

The Neutrino Mass Ordering (NMO) remains one of the outstanding questions in the field of neutrino physics. One strategy to measure the NMO is to observe matter effects in the oscillation pattern of atmospheric neutrinos above ∼ 1 GeV , as proposed for several next-generation neutrino experiments. Moreover, the existing IceCube DeepCore detector can already explore this type of measurement. We present the development and application of two independent analyses to search for the signature of the NMO with three years of DeepCore data. These analyses include a full treatment of systematic uncertainties and a statistically-rigorous method to determine the significance for the NMO from a fit to the data. Both analyses show that the dataset is fully compatible with both mass orderings. For the more sensitive analysis, we observe a preference for normal ordering with a p-value of p IO = 15.3 % and CL s = 53.3 % for the inverted ordering hypothesis, while the experimental results from both analyses are consistent within their uncertainties. Since the result is independent of the value of δ CP and obtained from energies E ν ≳ 5 GeV , it is complementary to recent results from long-baseline experiments. These analyses set the groundwork for the future of this measurement with more capable detectors, such as the IceCube Upgrade and the proposed PINGU detector. [ABSTRACT FROM AUTHOR]

Low-background searches for astrophysical neutrino sources anywhere in the sky can be performed using cascade events induced by neutrinos of all flavors interacting in IceCube with energies as low as ∼1 TeV. Previously we showed that, even with just two years of data, the resulting sensitivity to sources in the southern sky is competitive with IceCube and ANTARES analyses using muon tracks induced by charge current muon neutrino interactions—especially if the neutrino emission follows a soft energy spectrum or originates from an extended angular region. Here, we extend that work by adding five more years of data, significantly improving the cascade angular resolution, and including tests for point-like or diffuse Galactic emission to which this data set is particularly well suited. For many of the signal candidates considered, this analysis is the most sensitive of any experiment to date. No significant clustering was observed, and thus many of the resulting constraints are the most stringent to date. In this paper we will describe the improvements introduced in this analysis and discuss our results in the context of other recent work in neutrino astronomy. [ABSTRACT FROM AUTHOR]

Copyright of Der Chirurg is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

IceCube is a neutrino observatory deployed in the glacial ice at the geographic South Pole. The $$\nu _\mu $$ energy unfolding described in this paper is based on data taken with IceCube in its 79-string configuration. A sample of muon neutrino charged-current interactions with a purity of 99.5% was selected by means of a multivariate classification process based on machine learning. The subsequent unfolding was performed using the software Truee. The resulting spectrum covers an E $$_\nu $$ -range of more than four orders of magnitude from 125 GeV to 3.2 PeV. Compared to the Honda atmospheric neutrino flux model, the energy spectrum shows an excess of more than $$1.9\,\sigma $$ in four adjacent bins for neutrino energies $$E_\nu \ge 177.8\,\text {TeV}$$ . The obtained spectrum is fully compatible with previous measurements of the atmospheric neutrino flux and recent IceCube measurements of a flux of high-energy astrophysical neutrinos. [ABSTRACT FROM AUTHOR]

We present a search for a neutrino signal from darkmatter self-annihilations in theMilkyWay using the Ice-Cube Neutrino Observatory (IceCube). In 1005 days of data we found no significant excess of neutrinos over the background of neutrinos produced in atmospheric air showers from cosmic ray interactions. We derive upper limits on the velocity averaged product of the darkmatter self-annihilation cross section and the relative velocity of the dark matter particles 〈σAv〉. Upper limits are set for darkmatter particle candidate masses ranging from 10GeV up to 1TeV while considering annihilation through multiple channels. This work sets the most stringent limit on a neutrino signal from dark matter with mass between 10 and 100GeV, with a limit of 1.18 · 10-23 cm³s-1 for 100GeV dark matter particles self-annihilating via τ+τ- to neutrinos (assuming the Navarro–Frenk–White dark matter halo profile). [ABSTRACT FROM AUTHOR]

Copyright of Imago Mundi is the property of Routledge and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background:Panobinostat, a pan-deacetylase inhibitor, overcomes imatinib resistance in preclinical models of gastrointestinal stromal tumours (GIST). Here we determined the maximum tolerated dose (MTD) and dose-limiting toxicities (DLT) of panobinostat in combination with imatinib (IM) for treatment of patients with refractory GIST.Methods:Following a 7-day run-in phase of IM (400 mg per day), escalating doses of panobinostat were added following a '3 plus 3' design. Twelve heavily pretreated GIST patients were enrolled in two dose levels.Results:Most common adverse events were thrombocytopenia, anaemia, fatigue, creatinine elevation, nausea, emesis and diarrhoea. Twenty micrograms of panobinostat and 400 mg IM were declared the MTD. Pharmacologically active concentrations of panobinostat and IM were achieved as evidenced by histone H3 acetylation in blood mononuclear cells in vivo and inhibition of the IM-resistant KIT (D816) mutation in vitro. In FDG-PET-CT scans after IM run-in and following 3 weeks panobinostat treatment, 1 out of 11 evaluable patients showed a metabolic partial response, 7 patients were metabolically stable and 3 patients progressed. Longest treatment duration was 17 weeks (median 6).Conclusion:Panobinostat and IM can be administered at doses achieving target inhibition in vivo. Further clinical exploration of patients with treatment-refractory GIST is warranted. Correlative studies in this trial may help to optimise dosing schedules in GIST. [ABSTRACT FROM AUTHOR]

This work focuses on the design and characterization of a system for measuring and calibration of liquid micro-flows down to 5 nL min−1. The experimental setup relies on a telecentric imaging system mounted on a high-precision, computer controlled linear stage to track a moving liquid meniscus in a glass capillary. The position of the linear stage can be automatically adjusted to track the motion of the liquid front over distances of up to 15 cm. All fluidic components were placed inside a temperature regulated chamber at 36.0 ± 1.1 °C with a maximum variability ΔT = ± 0.1 °C for time intervals shorter than 1 h. The combined flow-rate uncertainty has been evaluated for measurement times from 15 s to 1 h and nominal flow rates between 5 and 50 nL min−1. At 5 nL min−1, an extended flow-rate uncertainty better that 8.3% can be attained for measurement times equal to or longer than 60 s. The uncertainty approaches asymptotically 5.4% for measurement times longer than 300 s or flow rates higher than 50 nL min−1. [ABSTRACT FROM AUTHOR]

The representation of acoustic stimuli in the brainstem forms the basis for higher auditory processing. While some characteristics of this representation (e.g. tuning curve) are widely accepted, it remains a challenge to predict the firing rate at high temporal resolution in response to complex stimuli. In this study we explore models for in vivo, single cell responses in the medial nucleus of the trapezoid body (MNTB) under complex sound stimulation. We estimate a family of models, the multilinear models, encompassing the classical spectrotemporal receptive field and allowing arbitrary input-nonlinearities and certain multiplicative interactions between sound energy and its short-term auditory context. We compare these to models of more traditional type, and also evaluate their performance under various stimulus representations. Using the context model, 75% of the explainable variance could be predicted based on a cochlear-like, gamma-tone stimulus representation. The presence of multiplicative contextual interactions strongly reduces certain inhibitory/suppressive regions of the linear kernels, suggesting an underlying nonlinear mechanism, e.g. cochlear or synaptic suppression, as the source of the suppression in MNTB neuronal responses. In conclusion, the context model provides a rich and still interpretable extension over many previous phenomenological models for modeling responses in the auditory brainstem at submillisecond resolution. [ABSTRACT FROM AUTHOR]

We make a case for improving the education of future rational decision-makers who will incorporate probabilistic thinking and not simply deterministic thinking in their processes of making decisions. The power of a system, systems thinking, and the power of thinking spatially, symbolically, and distributionally will be more naturally internalized by students who routinely use the tools of rational decision-making in both their coursework and their professional careers. Using the recent Social Security debate in the United States as a case example, we demonstrate how to enlarge the frame of the discussion, and hence change the course of the debate, to include uncertainty, market volatility, and the security of investments, not just their average rate of return. An important issue is identified and addressed by the use of a simple mathematical model based on difference equations and generating functions, which was implemented in Microsoft Excel along with the @RISK Monte Carlo Simulation program. The lessons learned can be used in many decision-making frameworks. [ABSTRACT FROM AUTHOR]

In this work we report on the magnetron reactive ion etch (MRIE) technology for gallium nitride (GaN) and aluminum gallium nitride (AlxGa1-xN) using dichlorodifluoromethane (CCl2F2), commonly known as halocarbon 12, with etch rates greater than 1,000 and 840 Å/min, respectively. Magnetic confinement of a very low pressure (10-4 Torr range) radio frequency (RF) discharge generates high-density plasmas, with low sheath voltages at the bounding surfaces, and very high dissociation of the source gas. Furthermore, the very low pressure of the etch process is characterized by long mean free paths so that sputtering contamination is reduced. MRIE chemistry has been monitored in situ by means of mass spectroscopy. Finally, we report on the successful fabrication of an indium gallium nitride (InxGa1-xN) blue light emitting diode (LED), whose fabrication sequence included the MRIE etching of GaN in CCl2F2. [ABSTRACT FROM AUTHOR]

Wolbachia are intracellular bacteria that induce phenotypic effects in many arthropod hosts to enhance their own transmission within host populations. Wolbachia commonly infect the Red Imported Fire Ant, Solenopsis invicta, in native South American populations. A previous study failed to detect Wolbachia in fire ants from the introduced range in the USA. We conducted an extensive study of individuals collected from 1157 nests from 10 widespread geographical populations in the USA. Wolbachia were detected in ants from two nearby populations in southern Mississippi, with different variants ( wsp gene sequences) infecting ants from colonies of the multiple-queen (polygyne) vs. single-queen (monogyne) social forms. The parsimonious explanation for the presence of Wolbachia in introduced S. invicta is that there have been one or more recent introductions of Wolbachia-infected fire ants into the southern USA. [ABSTRACT FROM AUTHOR]

Thermodynamic and phase diagram experimental data relevant to the La2O3-Ga2O3 system have been critically assessed. The system is characterized by the presence of two stoichiometric, congruently melting compounds LaGaO3 and La4Ga2O9, each occurring in two polymorphic modifications. A number of key experiments have been carried out to measure the heat capacity and to characterize phase transitions in both compounds as well as to determine the solubility of La in Ga2O3 and that of Ga in La2O3. These data were used together with information from the literature to generate self-consistent thermodynamic description of the La2O3-Ga2O3 system. [ABSTRACT FROM AUTHOR]

During operation at elevated temperatures, sintering processes can significantly influence the mechanical properties of thermal barrier coatings (TBCs) by increasing Young’s modulus and reducing strain tolerance. These changes of the mechanical response of TBCs were investigated using free-standing plasma-sprayed TBCs in a thermomechanical analysis (TMA) facility. The time-dependent change of Young’s modulus was determined in situ in a flexure mode at different annealing temperatures. In addition, relaxation processes during loading and unloading were monitored. The time-dependent deformation behavior of the TBC sample can be described by a simple viscoelastic approach (Burgers model). Viscosity data are determined as a function of annealing temperature and time. [ABSTRACT FROM AUTHOR]

Copyright of Der Internist is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

These cancer genetic counseling recommendations describe the medical, psychosocial, and ethical ramifications of identifying at-risk individuals through cancer risk assessment with or without genetic testing. They were developed by members of the Practice Issues Subcommittee of the National Society of Genetic Counselors Cancer Genetic Counseling Special Interest Group. The information contained in this document is derived from extensive review of the current literature on cancer genetic risk assessment and counseling as well as the personal expertise of genetic counselors specializing in cancer genetics. The recommendations are intended to provide information about the process of genetic counseling and risk assessment for hereditary cancer disorders rather than specific information about individual syndromes. Key components include the intake (medical and family histories), psychosocial assessment (assessment of risk perception), cancer risk assessment (determination and communication of risk), molecular testing for hereditary cancer syndromes (regulations, informed consent, and counseling process), and follow-up considerations. These recommendations should not be construed as dictating an exclusive course of management, nor does use of such recommendations guarantee a particular outcome. These recommendations do not displace a health care provider's professional judgment based on the clinical circumstances of a client. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To test the hypothesis that greater exposure to smoking in films is associated with trying smoking among adolescents. Design: Cross sectional survey of 4919 schoolchildren aged 9-15 years, and assessment of occurrence of smoking in 601 films. Setting: Randomly selected middle schools in Vermont and New Hampshire, USA. Main outcome measure: Number of schoolchildren who had ever tried smoking a cigarette. Results: The films contained a median of 5 (interquartile range 1-12) occurrences of smoking. The typical adolescent had seen 17 of 50 films listed. Exposure to smoking in films varied widely: median 91 (49-152) occurrences. The prevalence of ever trying smoking increased with higher categories of exposure: 4.9% among students who saw 0-50 occurrences of smoking, 13.7% for 51-100 occurrences, 22.1% for 101-150, and 31.3% for > 150. The association remained significant after adjustment for age; sex; school performance; school; parents' education; smoking by friend, sibling, or parent; and receptivity to tobacco promotions. The adjusted odds ratios of ever trying smoking for students in the higher categories of exposure, compared with students exposed to 0-50 occurrences of smoking in films, were 1.7 (95% confidence interval 1.2 to 2.4), 2.4 (1.7 to 3.4), and 2.7 (2.0 to 3.8). These odds ratios were not substantially affected by adjustment for parenting style or for personality traits of the adolescent. Conclusion: In this sample of adolescents there was a strong, direct, and independent association between seeing tobacco use in films and trying cigarettes, a finding that supports the hypothesis that smoking in films has a role in the initiation of smoking in adolescents. [ABSTRACT FROM AUTHOR]

We study the stability of viscometric flow using the type of short memory introduced by Akbay, Becker, Krozer and Sponagel. The instability found by these researchers is recognized as a 'change of type' leading to non-evolutionary character of the governing equations. We also address the question of justification for the short memory assumption and find that it cannot be justified for some of the more popular rheological models. [ABSTRACT FROM AUTHOR]

Tomato (Lycopersicon esculentum Mill.) genotypes varying in intrinsic firmness were examined to determine the quantitative relationships between polygalacturonase (EC 3.2.1.15) activity, firmness and other ripening parameters including rate (days from mature-green to full red) and intensity (rate of ethylene production at climacteric peak) of ripening. Texture, respiration and ethylene production were monitored in the immature-green through the red (ripe) stages of development. Polygalacturonase activity was measured by direct assay of salt-extractable wall protein or by monitoring the release of pectins from isolated, enzymically active wall. In all fruit, polygalacturonase activity was highly correlated with pericarp softening, but only moderately correlated with softening of whole fruit (r = 0.920 and 0.757, respectively). Polygalacturonase activity was positively correlated with cell-wall autolytic activity in pink (r = 0.969) and red (r = 0.900) fruit. Firmer genotypes exhibited lower rates of respiration and ethylene production during ripening. Polygalacturonase activity in isolates prepared from fruit at the climacteric peak was positively correlated with ethylene production and respiration, and negatively correlated with days to ripening (r= 0.929, 0.805, and -0.791, respectively). The data demonstrate the importance of selecting the appropriate method of firmness determination and are consistent with the hypothesis that pectin fragments released by polygalacturonase contribute to the production of autocatalytic (system II) ethylene. [ABSTRACT FROM AUTHOR]