eV-Scale Sterile Neutrino Search Using Eight Years of Atmospheric Muon Neutrino Data from the IceCube Neutrino Observatory

The results of a 3+1 sterile neutrino search using eight years of data from the IceCube Neutrino Observatory are presented. A total of 305 735 muon neutrino events are analyzed in reconstructed energy-zenith space to test for signatures of a matter-enhanced oscillation that would occur given a sterile neutrino state with a mass-squared differences between 0.01 and 100  eV^{2}. The best-fit point is found to be at sin^{2}(2θ_{24})=0.10 and Δm_{41}^{2}=4.5  eV^{2}, which is consistent with the no sterile neutrino hypothesis with a p value of 8.0%.

Characteristics of the Diffuse Astrophysical Electron and Tau Neutrino Flux with Six Years of IceCube High Energy Cascade Data

We report on the first measurement of the astrophysical neutrino flux using particle showers (cascades) in IceCube data from 2010-2015. Assuming standard oscillations, the astrophysical neutrinos in this dedicated cascade sample are dominated (∼90%) by electron and tau flavors. The flux, observed in the sensitive energy range from 16 TeV to 2.6 PeV, is consistent with a single power-law model as expected from Fermi-type acceleration of high energy particles at astrophysical sources. We find the flux spectral index to be γ=2.53±0.07 and a flux normalization for each neutrino flavor of ϕ_{astro}=1.66_{-0.27}^{+0.25} at E_{0}=100  TeV, in agreement with IceCube's complementary muon neutrino results and with all-neutrino flavor fit results. In the measured energy range we reject spectral indices γ≤2.28 at ≥3σ significance level. Because of high neutrino energy resolution and low atmospheric neutrino backgrounds, this analysis provides the most detailed characterization of the neutrino flux at energies below ∼100  TeV compared to previous IceCube results. Results from fits assuming more complex neutrino flux models suggest a flux softening at high energies and a flux hardening at low energies (p value ≥0.06). The sizable and smooth flux measured below ∼100  TeV remains a puzzle. In order to not violate the isotropic diffuse gamma-ray background as measured by the Fermi Large Area Telescope, it suggests the existence of astrophysical neutrino sources characterized by dense environments which are opaque to gamma rays.

Time-Integrated Neutrino Source Searches with 10 Years of IceCube Data

This Letter presents the results from pointlike neutrino source searches using ten years of IceCube data collected between April 6, 2008 and July 10, 2018. We evaluate the significance of an astrophysical signal from a pointlike source looking for an excess of clustered neutrino events with energies typically above ∼1  TeV among the background of atmospheric muons and neutrinos. We perform a full-sky scan, a search within a selected source catalog, a catalog population study, and three stacked Galactic catalog searches. The most significant point in the northern hemisphere from scanning the sky is coincident with the Seyfert II galaxy NGC 1068, which was included in the source catalog search. The excess at the coordinates of NGC 1068 is inconsistent with background expectations at the level of 2.9σ after accounting for statistical trials from the entire catalog. The combination of this result along with excesses observed at the coordinates of three other sources, including TXS 0506+056, suggests that, collectively, correlations with sources in the northern catalog are inconsistent with background at 3.3σ significance. The southern catalog is consistent with background. These results, all based on searches for a cumulative neutrino signal integrated over the 10 years of available data, motivate further study of these and similar sources, including time-dependent analyses, multimessenger correlations, and the possibility of stronger evidence with coming upgrades to the detector.

Constraints on Minute-Scale Transient Astrophysical Neutrino Sources

High-energy neutrino emission has been predicted for several short-lived astrophysical transients including gamma-ray bursts (GRBs), core-collapse supernovae with choked jets, and neutron star mergers. IceCube's optical and x-ray follow-up program searches for such transient sources by looking for two or more muon neutrino candidates in directional coincidence and arriving within 100 s. The measured rate of neutrino alerts is consistent with the expected rate of chance coincidences of atmospheric background events and no likely electromagnetic counterparts have been identified in Swift follow-up observations. Here, we calculate generic bounds on the neutrino flux of short-lived transient sources. Assuming an E^{-2.5} neutrino spectrum, we find that the neutrino flux of rare sources, like long gamma-ray bursts, is constrained to <5% of the detected astrophysical flux and the energy released in neutrinos (100 GeV to 10 PeV) by a median bright GRB-like source is <10^{52.5}  erg. For a harder E^{-2.13} neutrino spectrum up to 30% of the flux could be produced by GRBs and the allowed median source energy is <10^{52}  erg. A hypothetical population of transient sources has to be more common than 10^{-5}  Mpc^{-3}  yr^{-1} (5×10^{-8}  Mpc^{-3}  yr^{-1} for the E^{-2.13} spectrum) to account for the complete astrophysical neutrino flux.

Search for neutrinos from decaying dark matter with IceCube: IceCube Collaboration

With the observation of high-energy astrophysical neutrinos by the IceCube Neutrino Observatory, interest has risen in models of PeV-mass decaying dark matter particles to explain the observed flux. We present two dedicated experimental analyses to test this hypothesis. One analysis uses 6 years of IceCube data focusing on muon neutrino 'track' events from the Northern Hemisphere, while the second analysis uses 2 years of 'cascade' events from the full sky. Known background components and the hypothetical flux from unstable dark matter are fitted to the experimental data. Since no significant excess is observed in either analysis, lower limits on the lifetime of dark matter particles are derived: we obtain the strongest constraint to date, excluding lifetimes shorter than10 28 s at 90% CL for dark matter masses above 10 TeV .

Dark Matter Search Results from a One Ton-Year Exposure of XENON1T

We report on a search for weakly interacting massive particles (WIMPs) using 278.8 days of data collected with the XENON1T experiment at LNGS. XENON1T utilizes a liquid xenon time projection chamber with a fiducial mass of (1.30±0.01)  ton, resulting in a 1.0 ton yr exposure. The energy region of interest, [1.4,10.6]  keV_{ee} ([4.9,40.9] keV_{nr}), exhibits an ultralow electron recoil background rate of [82_{-3}^{+5}(syst)±3(stat)]  events/(ton yr keV_{ee}). No significant excess over background is found, and a profile likelihood analysis parametrized in spatial and energy dimensions excludes new parameter space for the WIMP-nucleon spin-independent elastic scatter cross section for WIMP masses above 6  GeV/c^{2}, with a minimum of 4.1×10^{-47}  cm^{2} at 30  GeV/c^{2} and a 90% confidence level.

The relationship between functional status, physical fitness and cognitive performance in physically active older adults: A pilot study

OBJECTIVE

Ageing is associated with a progressive decline in physical function and cognitive performance which could result in a shift from an independent to a more dependent lifestyle. The aim of this research study was to assess the fitness, functional performance and cognitive ability in independently living older South Africans and to determine which fitness parameters and functional performance tests best explain the variance in cognitive function.

DESIGN

Descriptive observational study.

PARTICIPANTS

Older adults with a mean age 71±4.7 years (n = 70; 28 men and 42 women) were recruited. Sixty percent of the sample completed at least secondary schooling and more than two-thirds were taking medication for a chronic medical condition.

MEASUREMENTS

Self-reported physical activity was assessed using the Yale Physical Activity Survey. Fitness tests included the 6-minute walk test and Bicep Curls. The functional performance tests were; Static and Dynamic balance, Timed Up and Go, Sit to Stand, Grip strength and Functional Reach. The Stroop Task and 6-Item cognitive impairment test were used to measure cognitive performance. Bivariate and multivariate analyses were conducted between performance on the novel cognitive Stroop Task and functional and cognitive tests.

RESULTS

We found significant relationships between the number of correct responses on the Stroop Task and scores on the 6-Item Cognitive Impairment test (-0.520, p < 0.01) and grip strength (r = 0.42, p< 0.01). The number of incorrect responses was inversely associated with functional reach (r = -0.445, p< 0.01). The final regression model included: age, dynamic balance, right arm grip strength and the score on the 6-item cognitive impairment test, and explained 44% of the variance in performance of the Stroop Task.

CONCLUSIONS

The results of this study showed that measures of physical function were associated with cognitive performance even in highly functioning older South African adults. Further research is needed to determine the extent to which exercise training can improve functional capacity and the effect on cognitive performance.

First Dark Matter Search Results from the XENON1T Experiment

We report the first dark matter search results from XENON1T, a ∼2000-kg-target-mass dual-phase (liquid-gas) xenon time projection chamber in operation at the Laboratori Nazionali del Gran Sasso in Italy and the first ton-scale detector of this kind. The blinded search used 34.2 live days of data acquired between November 2016 and January 2017. Inside the (1042±12)-kg fiducial mass and in the [5,40]  keV_{nr} energy range of interest for weakly interacting massive particle (WIMP) dark matter searches, the electronic recoil background was (1.93±0.25)×10^{-4}  events/(kg×day×keV_{ee}), the lowest ever achieved in such a dark matter detector. A profile likelihood analysis shows that the data are consistent with the background-only hypothesis. We derive the most stringent exclusion limits on the spin-independent WIMP-nucleon interaction cross section for WIMP masses above 10  GeV/c^{2}, with a minimum of 7.7×10^{-47}  cm^{2} for 35-GeV/c^{2} WIMPs at 90% C.L.

Search for Electronic Recoil Event Rate Modulation with 4 Years of XENON100 Data

We report on a search for electronic recoil event rate modulation signatures in the XENON100 data accumulated over a period of 4 yr, from January 2010 to January 2014. A profile likelihood method, which incorporates the stability of the XENON100 detector and the known electronic recoil background model, is used to quantify the significance of periodicity in the time distribution of events. There is a weak modulation signature at a period of 431_{-14}^{+16} day in the low energy region of (2.0-5.8) keV in the single scatter event sample, with a global significance of 1.9σ; however, no other more significant modulation is observed. The significance of an annual modulation signature drops from 2.8σ, from a previous analysis of a subset of this data, to 1.8σ with all data combined. Single scatter events in the low energy region are thus used to exclude the DAMA/LIBRA annual modulation as being due to dark matter electron interactions via axial vector coupling at 5.7σ.

Search for Event Rate Modulation in XENON100 Electronic Recoil Data

We have searched for periodic variations of the electronic recoil event rate in the (2-6) keV energy range recorded between February 2011 and March 2012 with the XENON100 detector, adding up to 224.6 live days in total. Following a detailed study to establish the stability of the detector and its background contributions during this run, we performed an unbinned profile likelihood analysis to identify any periodicity up to 500 days. We find a global significance of less than 1σ for all periods, suggesting no statistically significant modulation in the data. While the local significance for an annual modulation is 2.8σ, the analysis of a multiple-scatter control sample and the phase of the modulation disfavor a dark matter interpretation. The DAMA/LIBRA annual modulation interpreted as a dark matter signature with axial-vector coupling of weakly interacting massive particles to electrons is excluded at 4.8σ.

Quantitative determination of steroid hormone receptor positive cells in the synovium of patients with rheumatoid arthritis and osteoarthritis: is there a link to inflammation?

BACKGROUND

Steroid hormone receptors such as glucocorticoid receptors, androgen receptors, and oestrogen receptors alpha (ERalpha) and beta (ERbeta) have been identified in synovial cells of patients with rheumatoid arthritis and osteoarthritis.

OBJECTIVES

To find a quantitative relationship between the number of receptor positive cells and markers of inflammation, and to compare the two groups of patients with rheumatoid arthritis and osteoarthritis.

METHODS

A total of 36 patients with rheumatoid arthritis (n = 17) and osteoarthritis (n = 19) were included, and receptor positive cells and cellular markers of synovial inflammation were quantified by immunohistochemistry and ELISA (interleukin 6 (IL6) and IL8).

RESULTS

Patients with rheumatoid arthritis showed a higher degree of histologically determined inflammation compared with those with osteoarthritis. However, synovial density of gluco-corticoid receptor positive (GR+), androgen receptor positive (AR+), ERalpha+ and ERbeta+ cells were not different among patients with rheumatoid arthritis and osteoarthritis. In patients with osteoarthritis, the density of GR+ cells positively correlated with the density of AR+, ERalpha+ and ERbeta+ cells (p = 0.007), which was not observed in patients with rheumatoid arthritis. This indicates positively coupled steroid hormone receptor expression in patients with osteoarthritis but not in those with rheumatoid arthritis. In patients with rheumatoid arthritis, secretion of synovial IL6 and IL8 positively correlated with the density of ERalpha+ and ERbeta+ cells (not with gluco-corticoid receptor and androgen receptor), which was not found in the synovium of patients with osteoarthritis. This indicates that inflammatory factors might up regulate the expression of oestrogen receptors in patients with rheumatoid arthritis, or vice versa.

CONCLUSIONS

In patients with osteoarthritis, expression of different steroid receptors is positively coupled, which was not observed in the synovium of patients with rheumatoid arthritis. This uncoupling phenomenon in rheumatoid arthritis might lead to an imbalance of the normal synovial homeostasis.

[Sensitivity to constituents of bone cement in a patient with joint prosthesis]

Failure to tolerate prosthetic material can lead to a variety of clinical findings. A 55-year-old woman had a total replacement of the right knee. Two weeks later she developed pruritic skin lesions over the joint, as well as pain and impaired function. Allergic testing showed clinically relevant Type IV sensitization to methylmethacrylate, as well as to various formulations of the bone cement, including one with an added antibiotic. The symptom complex of pruritic skin lesions in the area of the prosthesis, pain and disability, as well as relevant Type IV sensitization justified replacing the prosthesis.

[Aesthetic dermatology. Botulinumtoxin A and soft tissue augmentation]

Younger and younger patients are undergoing aesthetic procedures to achieve "wrinkle-free" aging. This has had great impact on the field of aesthetic dermatology. The rapid development of new indications and filler materials requires a critical approach to the available substances particularly concerning side effects and long-term effects. The quality of the chosen approach depends on the applied filler substance, clear indication the compliance of the patient and the experience of the physician. The growing expectations of patients require a critical analysis of the available therapy options. Botulinum toxin A is one of the preferred treatments for wrinkles secondary to facial expression. In addition there are a variety of biologically inert and completely resorbable filler materials such as collagen and hyaluronic acid and autologous materials such as fat implants or plasma gel available. This article gives an overview about the most common fillers and their use in aesthetic dermatology.

Cowden's disease: clinical and molecular genetic findings in a patient with a novel PTEN germline mutation

We report a 54-year-old woman with Cowden's disease (CD) who was found to carry a novel germline mutation in the PTEN gene. The mutation (c.334C-->G) introduced a splice donor site within exon 5 that caused the expression of an aberrant transcript lacking 159 nucleotides corresponding to codons 112-164. Clinically, the patient showed multiple benign hamartomatous lesions of the skin, papillomatosis of the lips and oral mucosa, polyposis coli and bilateral fibrocystic disease of the breast. In addition, she developed different types of malignant neoplasms, including bilateral carcinomas of the breast and malignant melanomas of the skin. Molecular genetic analysis of a benign skin hamartoma and an invasive ductal breast carcinoma revealed loss of heterozygosity (LOH) at microsatellite markers on chromosome 10 in the carcinoma but not in the hamartoma. The breast carcinoma additionally carried a somatic TP53 point mutation (c.466C-->G; R156G) that was associated with LOH on 17p and nuclear p53 protein accumulation. Taken together, our findings indicate that benign hamartomas in CD may develop without loss of the second (wild-type) PTEN allele, whereas the pathogenesis of malignant tumours, such as breast carcinomas, appears to require the complete inactivation of Pten as well as further alterations such as the loss of p53-dependent growth control.

Botulinum toxin A in the therapy of mimic facial lines

In aesthetic medicine, many different methods of skin rejuvenation are available. At the end of the 1980s, the neurotoxin Botulinum toxin A (BT-A) led to a revolution in aesthetic-corrective dermatology for the treatment of mimic facial wrinkles. The toxin is produced by Clostridium botulinum and causes a reversible, selective muscle relaxation that leads to a temporary flattening of the mechanical part of wrinkling without the stigmata of invasive surgery. After two decades of experience in different medical disciplines, there has been remarkable clinical development and progress in research, the identification of new botulinum toxin serotypes, and also innovation in indications and combined modalities. These lead to new and interesting questions. BT-A offers the experienced, critical dermatologist a time-saving, effective, cosmetically satisfactory, non-invasive treatment for mimic facial wrinkles and neck and decollete lines, with only minor side effects. Dermatologists should have a profound anatomical knowledge and should be able to perform all injection techniques to meet the needs of ever more demanding patients and to ensure optimization of patient satisfaction. The following review summarizes the historical development and the mechanism of action of both frequently and rarely used injection techniques with BT-A for the treatment of wrinkles and lines of the upper face, neck and décolleté, and gives an update of different experiences encountered.

The poet syndrome: opiates, psychosis and creativity

For some people, heroin is a self-medicating tool used to control innate psychic sensitivity. The habitual use of heroin provides the sensitive addict with a definition of consciousness by containment, psychic buffering, and psychic marking. This article is an examination of the political and social history of opiates, opiates as antipsychotics, "drug of choice" as a determinant of self-medication, and the connection between creativity, spirituality, psychosis and addiction. Using clinical observation, the article explores the poet syndrome hypothesis and offers direction for an alternative drug treatment paradigm.

Consequences of queuing for care at a public hospital emergency department

OBJECTIVE

To determine whether the length of a queue at a public hospital emergency department was associated with increased likelihood of patients' leaving without being seen by a physician and whether leaving adversely affected patients' health or affected their subsequent use of health care services.

DESIGN

Observational cohort. Patients were surveyed during 1 week in July 1990 and received a follow-up survey 7 to 14 days later. The responses of patients who left without being seen by a physician were compared with those who were seen by a physician.

SETTING

Emergency department at San Francisco (Calif) General Hospital.

PATIENTS

All English-, Spanish-, and Cantonese-speaking adults waiting for emergency care were eligible. Of 882 eligible individuals, 700 agreed to participate; 85% of enrolled subjects saw a physician and 15% left without being seen. Demographic characteristics of patients who were and who were not seen were not significantly different.

MAIN OUTCOME MEASURES

Emergency department waiting time and changes in patients' self-reported health.

RESULTS

Patients were more likely to leave as waiting times increased. At follow-up, patients who left without being seen were twice as likely as those who were seen to report that their pain or the seriousness of their problem was worse. Only 4% of patients who left required subsequent hospitalization, but 27% returned to an emergency department.

CONCLUSION

Many patients can appropriately decide whether their problem is truly urgent and make alternative plans in the face of long waits, but the health of some patients may be jeopardized by long queues for emergency care.