Observation of Seven Astrophysical Tau Neutrino Candidates with IceCube.

We report on a measurement of astrophysical tau neutrinos with 9.7 yr of IceCube data. Using convolutional neural networks trained on images derived from simulated events, seven candidate ν_{τ} events were found with visible energies ranging from roughly 20 TeV to 1 PeV and a median expected parent ν_{τ} energy of about 200 TeV. Considering backgrounds from astrophysical and atmospheric neutrinos, and muons from π^{±}/K^{±} decays in atmospheric air showers, we obtain a total estimated background of about 0.5 events, dominated by non-ν_{τ} astrophysical neutrinos. Thus, we rule out the absence of astrophysical ν_{τ} at the 5σ level. The measured astrophysical ν_{τ} flux is consistent with expectations based on previously published IceCube astrophysical neutrino flux measurements and neutrino oscillations.

Observation of high-energy neutrinos from the Galactic plane.

The origin of high-energy cosmic rays, atomic nuclei that continuously impact Earth's atmosphere, is unknown. Because of deflection by interstellar magnetic fields, cosmic rays produced within the Milky Way arrive at Earth from random directions. However, cosmic rays interact with matter near their sources and during propagation, which produces high-energy neutrinos. We searched for neutrino emission using machine learning techniques applied to 10 years of data from the IceCube Neutrino Observatory. By comparing diffuse emission models to a background-only hypothesis, we identified neutrino emission from the Galactic plane at the 4.5σ level of significance. The signal is consistent with diffuse emission of neutrinos from the Milky Way but could also arise from a population of unresolved point sources.

Evidence for neutrino emission from the nearby active galaxy NGC 1068.

A supermassive black hole, obscured by cosmic dust, powers the nearby active galaxy NGC 1068. Neutrinos, which rarely interact with matter, could provide information on the galaxy's active core. We searched for neutrino emission from astrophysical objects using data recorded with the IceCube neutrino detector between 2011 and 2020. The positions of 110 known gamma-ray sources were individually searched for neutrino detections above atmospheric and cosmic backgrounds. We found that NGC 1068 has an excess of [Formula: see text] neutrinos at tera-electron volt energies, with a global significance of 4.2σ, which we interpret as associated with the active galaxy. The flux of high-energy neutrinos that we measured from NGC 1068 is more than an order of magnitude higher than the upper limit on emissions of tera-electron volt gamma rays from this source.

Search for Unstable Sterile Neutrinos with the IceCube Neutrino Observatory.

We present a search for an unstable sterile neutrino by looking for a resonant signal in eight years of atmospheric ν_{µ} data collected from 2011 to 2019 at the IceCube Neutrino Observatory. Both the (stable) three-neutrino and the 3+1 sterile neutrino models are disfavored relative to the unstable sterile neutrino model, though with p values of 2.8% and 0.81%, respectively, we do not observe evidence for 3+1 neutrinos with neutrino decay. The best-fit parameters for the sterile neutrino with decay model from this study are Δm_{41}^{2}=6.7_{-2.5}^{+3.9} eV^{2}, sin^{2}2θ_{24}=0.33_{-0.17}^{+0.20}, and g^{2}=2.5π±1.5π, where g is the decay-mediating coupling. The preferred regions of the 3+1+decay model from short-baseline oscillation searches are excluded at 90% C.L.

Strong Constraints on Neutrino Nonstandard Interactions from TeV-Scale ν_{µ} Disappearance at IceCube.

We report a search for nonstandard neutrino interactions (NSI) using eight years of TeV-scale atmospheric muon neutrino data from the IceCube Neutrino Observatory. By reconstructing incident energies and zenith angles for atmospheric neutrino events, this analysis presents unified confidence intervals for the NSI parameter ε_{µτ}. The best-fit value is consistent with no NSI at a p value of 25.2%. With a 90% confidence interval of -0.0041≤ε_{µτ}≤0.0031 along the real axis and similar strength in the complex plane, this result is the strongest constraint on any NSI parameter from any oscillation channel to date.

Impact of decompressive craniectomy on functional outcome after severe traumatic brain injury.

BACKGROUND: The beneficial effect of decompressive craniectomy (DC) in the treatment of traumatic brain injury (TBI) remains controversial. In many centers, it is used as a salvage procedure for uncontrollable intracranial pressure (ICP). It is our contention that DC represents a viable early option for head trauma patients. The purpose of this study was to evaluate the efficacy of DC on functional outcome after severe TBI in the largest single institutional series reported in the literature. METHODS: Patients with severe TBI (Abbreviated Injury Score 4-5) treated with DC for the management of increased ICP during 6-year period were identified from the trauma registry. Functional outcome was measured 1 year to 6 years postinjury using the Glasgow Outcome Score Extended (GOSE) via telephone interview and classified as good (GOSE 5-8) or poor (GOSE 1-4, including death). Outcomes were compared using Wilcoxon rank-sum and chi2 tests where appropriate. RESULTS: One hundred and seventy-one patients were identified: 137 (80%) men and 34 (20%) women. Overall mortality (all in-hospital) was 32% (head-related = 22%). Of the 117 survivors, follow-up was obtained in all but 6 (95%). Good outcome was achieved in 96 patients (56% overall, 82% of survivors). Those with good outcome were younger (26 years vs. 43 years, p = 0.0028) and experienced a greater change in predecompression to postdecompression ICP (ICP reduced by 23 mm Hg vs. 10 mm Hg, p < 0.0001). Not surprisingly, unchanged ICP (predecompression to postdecompression) was associated with poor outcome (p = 0.0031). There was no difference in immediate predecompression ICP between survivors versus nonsurvivors. However, immediate predecompression Glasgow Coma Score was significantly higher in survivors compared with nonsurvivors (7 vs. 5, p < 0.0001). CONCLUSIONS: DC resulted in good functional outcome in >50% of patients with severe TBI. The greatest benefit was observed in younger patients with a demonstrable reduction in ICP after decompression. The prospect of improved functional outcome offered by this procedure in the treatment of severe TBI warrants prospective investigation.

The Virginia generalist initiative: lessons learned in a statewide consortium.

In response to Virginia's need for an increased supply of generalist physicians, the state's three medical schools--Eastern Virginia Medical School, Virginia Commonwealth University School of Medicine, and the University of Virginia School of Medicine--have formed a partnership with key governmental stakeholders in the Virginia Generalist Initiative funded by The Robert Wood Johnson Foundation's Generalist Physician Initiative. These state-supported medical schools historically have functioned independently, with little cooperative effort. This paper describes the consortium, its activities, its successes, and its unmet objectives, and uses a series of cases in point to illustrate relevant lessons learned. Some of these lessons are that (1) stakeholders must be involved from the beginning of planning to identify mutual goals and establish consortium protocols; (2) all partners must share a philosophical commitment to the consortium's mission, as well as the time and resources needed; (3) an atmosphere that enables risk-taking behavior must be created; (4) stakeholders must be willing to revise goals and sustain an environment conductive to change; and (5) trust is essential and must be vigilantly maintained. The paper concludes that the Virginia Generalist Initiative has dramatically altered the goals, objectives and programs of the three schools and has succeeded in aligning the schools' strategic objectives with the state's priorities.