Targeted temperature management and PbtO2 in traumatic brain injury

Introduction

Targeted Temperature Management (TTM) to normothermia is widely used in traumatic brain injury (TBI). We investigated the effects to of TTM to normothermia patients with TBI (GCS≤12) monitored with multimodality monitoring, to better understand the physiological consequences of this intervention.

Research question

In TBI patients cooled to normothermia and in which brain oxygenation deteriorates, are there changes in physiological parameters which are pertinent to brain oxygenation?

Material and method

102 TBI patients with continuous recordings of intracranial pressure (ICP) and brain oxygen tension (PbtO2) were studied retrospectively. Non-continuous arterial carbon dioxide (PaCO2) and oxygen (PaO2) tensions, and core body temperature (Tc) were added. PaO2 and PaCO2 were also corrected for Tc. Transitions from elevated Tc to normothermia were identified in 39 patients. The 8 h pre and post the transition to normothermia were compared. Data is given as median [IQR] or mean (SD).

Results

Overall, normothermia reduced ICP (12 [9-18] -11 [8-17] mmHg, p < 0.009) and Tcore (38.3 [0.3]-36.9 [0.4] oC, p < 0.001), but not PbtO2 (23.3 [16.6]-24.4 [17.2-28.7] mmHg, NS). Normothermia was associated with a fall in PbtO2 in 18 patients (24.5 [9.3] -20.8 [7.6] mmHg). Only in those with a fall in PbtO2 with cooling did ICP (15 [10.8-18.5] -12 [7.8-17.3] mmHg, p = 0.002), and temperature corrected PaCO2 (5.3 [0.5]- 4.9 [0.8] kPa, p = 0.001) decrease.

Discussion and conclusion

A reduction in PbtO2 was only present in the subgroup of patients with a fall in temperature corrected PaCO2 with cooling. This suggests that even modest temperature changes could result in occult hyperventilation in some patients. pH stat correction of ventilation may be an important factor to consider in future TTM protocols.

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 79 − 20 + 22 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.

Search for Relativistic Magnetic Monopoles with Eight Years of IceCube Data

We present an all-sky 90% confidence level upper limit on the cosmic flux of relativistic magnetic monopoles using 2886 days of IceCube data. The analysis was optimized for monopole speeds between 0.750c and 0.995c, without any explicit restriction on the monopole mass. We constrain the flux of relativistic cosmic magnetic monopoles to a level below 2.0×10^{-19}  cm^{-2} s^{-1} sr^{-1} over the majority of the targeted speed range. This result constitutes the most strict upper limit to date for magnetic monopoles with β≳0.8 and up to β∼0.995 and fills the gap between existing limits on the cosmic flux of nonrelativistic and ultrarelativistic magnetic monopoles.

COVID-19 PANDEMIC INDUCED DISRUPTIONS IN TROPONIN AND LOW-DENSITY LIPOPROTEIN CHOLESTEROL LABORATORY TEST VOLUMES ACROSS ALBERTA

BACKGROUND

Atherosclerotic cardiovascular disease (ASCVD) is a leading cause of morbidity and mortality in Canada and worldwide. Laboratory tests, including troponin and low-density lipoprotein cholesterol (LDL-C), are important biomarkers of ASCVD risk. The objective of this study was to investigate patterns of testing for troponin and LDL-C test volumes among Alberta residents during the coronavirus disease 2019 (COVID-19) pandemic.

METHODS AND RESULTS

A repeated cross-sectional study design captured population-level laboratory test volumes between March 15, 2019 and December 14, 2020. Three-month cross-sections were derived to report laboratory test volumes by different COVID-19 restriction periods during 2020-2021 and using 2019-2020 as a preceding control period. Percent change for troponin and LDL-C test volumes were calculated for both control and COVID-19 periods among adult (≥18 years of age) Alberta residents, and stratified by age (18-49, 50-65, 66-79, and ≥80 years), sex, and geographic zones (urban, rural). This preliminary data is part of an ongoing study for which further troponin and LDL-C test volumes will be available up until March 14, 2021 (representing one year of data throughout the COVID-19 pandemic). Among the Alberta population, 292,836 troponin and 794,789 LDL-C tests were captured between March 15, 2020 and December 14, 2020 (Figure 1). Testing patterns during the COVID-19 restriction period showed marked reduction in test volumes from the previous year. The initial cross-section of the COVID-19 period (March-June 2020) was characterized by the largest overall reduction with troponin test volumes decreasing 18% and LDL-C test volumes decreasing 63%, compared to the year prior. As restrictions eased in the summer months of 2020, testing volumes rebounded to near pre-pandemic volumes for both tests. However, in the fall of 2020, troponin tests decreased again (-15%). Within these drops in utilization, slightly larger relative declines were observed for troponin test volumes in women (-20%) and patients ≥80 years-old (-25%) and for LDL-C test volumes among urban residents (-64%), women (-67%) and patients aged 18-49 (-66%) and 50-65 (-65%) years (Table 1).

CONCLUSION

This study describes declines in troponin and LDL-C test volumes in the initial and second COVID-19 lockdown periods. Women had overall smaller total troponin and LDL-C test volumes and larger relative declines during the pandemic compared to men. The decrease in these ASCVD-related laboratory test volumes during the pandemic may have been accompanied by other important changes in indicators of healthcare utilization and associated clinical outcomes. Ongoing analyses will further explore the impact of the pandemic.

How safe are gloves and masks used for protection against Legionella longbeachae infection when gardening?

Legionella longbeachae has been frequently identified in composted plant material and can cause Legionnaires' disease (LD). We wanted to determine how frequently L. longbeachae DNA was present on gardeners' gloves, and how long L. longbeachae could persist on inoculated gloves and masks. Volunteers completed a survey of gardening practices and their gardening gloves were tested for L. longbeachae DNA by qPCR. The persistence of viable L. longbeachae was assessed by timed subcultures after inoculation of gardening gloves and masks. Gloves but not masks were used regularly. L. longbeachae was detected on 11 (14%; 95% CI 8-24%) gloves. Viable organisms were recovered from 25-50% of inoculated cotton, leather and PU coated gloves but not rubber gloves after 8 h incubation. There was a difference in dose-response curve slopes by glove material (P = 0·001) and time to 50% sterility (P = 0·036). There were differences in persistence of L. longbeachae between mask types from analysis of the slopes and 50% sterility on the decay curves (P = 0·042, P < 0·001 respectively). Gardening gloves and masks may act as a vector for transmission of L. longbeachae during gardening. Washing gardening gloves and prompt disposal of masks could reduce risk of LD.

Outcome following surgery to treat septic peritonitis in 95 cats in the United Kingdom

OBJECTIVES

To review the cause, management and outcome in cats with septic peritonitis within the United Kingdom (2008 to 2018) and to identify if previously identified prognostic factors were associated with survival in this population.

MATERIALS AND METHODS

Clinical records from 10 referral hospitals in United Kingdom were reviewed. Data collected included signalment, clinicopathological data and management techniques. Serum albumin, glucose, lactate and ionised calcium concentration; presence of intraoperative hypotension and correct empirical antibiosis were analysed via logistic regression for association with survival.

RESULTS

Ninety-five cats were included. The overall survival rate was 66%. Lethargy (89%) and anorexia (75%) were the most common clinical signs, with abdominal pain and vomiting in 44% and 27% of cases, respectively. Gastro-intestinal leakage was the most common source of contamination. The presence of an abdominal mass on clinical examination was not strongly predictive of the presence of neoplasia on histology and did not confer a worse prognosis. Cats presenting with dehiscence of a previous enterotomy/enterectomy did not have a worse prognosis than those presenting with other aetologies. Intraoperative hypotension (adjusted odds ratio 0.173, 95% confidence intervals 0.034 to 0.866, P=0.033) was associated with non-survival. Cats that survived beyond 1 day postoperatively had an improved likelihood of survival (87.5%). All cats that survived beyond 6 days were successfully discharged.

CLINICAL SIGNIFICANCE

This study describes the largest group of cats with septic peritonitis with an overall survival rate of 66%. The presence of an abdominal mass on clinical examination or having dehiscence of a previous gastrointestinal surgery did not confer a worse prognosis.

Assessment of the status and trends in abundance of a coastal pinniped, the Australian sea lion Neophoca cinerea

Australian sea lions Neophoca cinerea are endemic to Australia, with their contemporary distribution restricted to South Australia (SA) and Western Australia (WA). Monitoring of the species has proved challenging due to prolonged breeding events that occur non-annually and asynchronously across their range. The most recent available data from 80 extant breeding sites (48 in SA, 32 in WA) enabled us to estimate the species-wide pup abundance to be 2739, with 82% (2246) in SA and 18% (493) in WA, mostly based on surveys conducted between 2014 and 2019. We evaluated 1776 individual site-surveys undertaken between 1970 and 2019 and identified admissible time-series data from 30 breeding sites, which revealed that pup abundance declined on average by 2.0% yr-1 (range 9.9% decline to 1.7% growth yr-1). The overall reduction in pup abundance over 3 generations (42.3 yr) was estimated to be 64%, with over 98% of Monte Carlo simulations producing a decline >50% over a 3-generation period, providing strong evidence that the species meets IUCN ‘Endangered’ criteria (decline ≥50% and ≤80%). The population is much smaller than previously estimated and is declining. There is a strong cline in regional abundances (increasing from west to east), with marked within-region heterogeneity in breeding site pup abundances and trends. Results from this study should improve consistency in the assessment of the species and create greater certainty among stakeholders about its conservation status. To facilitate species management and recovery, we prioritise key data gaps and identify factors to improve population monitoring.

Consensus of All Solutions for Intractable Phylogenetic Tree Inference

Solving median tree problems is a classic approach for inferring species trees from a collection of discordant gene trees. Median tree problems are typically NP-hard and dealt with by local search heuristics. Unfortunately, such heuristics generally lack provable correctness and precision. Algorithmic advances addressing this uncertainty have led to exact dynamic programming formulations suitable to solve a well-studied group of median tree problems for smaller phylogenetic analyses. However, these formulations allow computing only very few optimal species trees out of possibly many such trees, and phylogenetic studies often require the analysis of all optimal solutions through their consensus tree. Here, we describe a significant algorithmic modification of the dynamic programming formulations that compute the cluster counts of all optimal species trees from which various types of consensus trees can be efficiently computed. Through experimental studies, we demonstrate that our parallel implementation of the modified dynamic programming formulation is more efficient than a previous implementation of the original formulation. Finally, we show that the parallel implementation can rapidly identify novel reassorted influenza A viruses potentially facilitating pandemic preparedness efforts.

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.

Post-release survival of fallout Newell’s shearwater fledglings from a rescue and rehabilitation program on Kaua‘i, Hawai‘i

Light attraction impacts nocturnally active fledgling seabirds worldwide and is a particularly acute problem on Kaua‘i (the northern-most island in the main Hawaiian Island archipelago) for the Critically Endangered Newell’s shearwaterPuffinus newelli. The Save Our Shearwaters (SOS) program was created in 1979 to address this issue and to date has recovered and released to sea more than 30500 fledglings. Although the value of the program for animal welfare is clear, as birds cannot simply be left to die, no evaluation exists to inform post-release survival. We used satellite transmitters to track 38 fledglings released by SOS and compared their survival rates (assessed by tag transmission duration) to those of 12 chicks that fledged naturally from the mountains of Kaua‘i. Wild fledglings transmitted longer than SOS birds, and SOS birds with longer rehabilitation periods transmitted for a shorter duration than birds released immediately or rehabilitated for only 1 d. Although transmitter durations from grounded fledglings were shorter (indicating impacts to survivorship), some SOS birds did survive and dispersed out to sea. All surviving birds (wild and SOS) traveled more than 2000 km to the southwest of Kaua‘i, where they concentrated mostly in the North Pacific Equatorial Countercurrent Province, revealing a large-scale annual post-breeding aggregation zone for fledgling Newell’s shearwaters. While there was reduced survival among birds undergoing rehabilitation, SOS remains an important contribution toward the conservation of Newell’s shearwater because a proportion of released birds do indeed survive. However, light attraction, the root cause of fallout, remains a serious unresolved issue on Kaua’i.

Understanding the Ecological Validity of Relying Practice as a Basis for Risk Identification

Understanding the reliability of hazardous organizations and their protective systems is central to understanding the risk they produce. Work on "high reliability organization" has done much to illuminate the conditions in which social organization becomes reliable in highly demanding conditions. But risk depends just as much on how relying entities do their relying as it does on the reliability of the entities they rely on. Patterns of relying are often opaque in sociotechnical systems, and processes of relying and being relied on are mutually influencing in complex ways, so the relationship between relying and risk may not be at all obvious. This study was an attempt to study relying as a social practice, in particular analyzing how it had ecological validity in a social organization-how practice was responsive to the conditions in which it took place. This involved observational fieldwork and inductive, qualitative analysis on an offshore oil and gas production platform that was nearing the end of its design life and undergoing refurbishment. The analysis produced four main categories of ecological validity: responsiveness to formal organization, responsiveness to situational contingency, responsiveness to information asymmetry, and responsiveness to sociomateriality. This ecological validity of relying practice should be a primary focus of risk identification, assessing how relying can become mismatched to reliability in certain ways, both when relying practice is responsive to circumstances and when it is not.

Diaphragmotomy to aid exposure during hepatobiliary surgery: a multi-centre retrospective review of 31 dogs

OBJECTIVES

To report surgical technique, intra- and post-operative complications, and short- and long-term outcome following canine hepatobiliary surgery in which exposure of intra-abdominal hepatobiliary lesions was aided by diaphragmotomy.

MATERIALS AND METHODS

Clinical records from four multi-disciplinary UK-based small animal referral hospitals were retrospectively reviewed for dogs in which diaphragmotomy was performed between January 2014 and May 2019. Signalment, diagnosis, surgery performed, diaphragmotomy technique, management of diaphragmotomy and pneumothorax, intra- and post-operative complications, short-term outcome and long-term outcome were recorded.

RESULTS

Thirty-one cases were identified. The most common hepatobiliary surgeries performed alongside diaphragmotomy were single hepatic lobectomy (14/31) and cholecystectomy (11/31). The most common diagnoses were hepatocellular carcinoma (10/31), gall bladder mucocoele (7/31) and hepatic nodular hyperplasia (4/31). Peri-operative mortality rate was 9.7% (3/31 cases) though none of these deaths were considered attributable to diaphragmotomy. Post-operative complications were encountered in 67.9% (19/28) cases that survived the peri-operative period, of which 25.0% (7/28) suffered complications that were considered attributable or likely attributable to diaphragmotomy. These seven complications resolved following non-surgical intervention. Follow-up was available for 26 of 28 patients that survived to discharge at a median of 4-months (range 10 days to 24 months) following surgery and revealed no evidence of complications related to diaphragmotomy.

CLINICAL SIGNIFICANCE

Diaphragmotomy appears safe and increases abdominal exposure of hepatobiliary lesions. The benefit of improved exposure must be carefully weighed up against the risks inherent in inducing pneumothorax.

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.

Effects of Chlorpyrifos on Cholinesterase and Serine Lipase Activities and Lipid Metabolism in Brains of Rainbow Trout (Oncorhynchus mykiss)

Chlorpyrifos is an organophosphorus insecticide that elicits acute toxicity through inhibition of acetylcholinesterase (AChE), leading to acetylcholine accumulation and prolonged stimulation of cholinergic receptors throughout the central and peripheral nervous systems. Previous studies have indicated that neurodevelopment may also be impaired through alternative pathways, including reduction of cAMP catalyzed downstream events. The upstream initiating events that underlie non-cholinergic neurological actions of chlorpyrifos and other organophosphorus compounds remain unclear. To investigate the potential role of disruption of fatty acid signaling as a mechanism of toxicity, lipid metabolism and fatty acid profiles were examined to identify alterations that may play a critical role in upstream signaling in the CNS. Juvenile rainbow trout were treated for 7 days with nominal chlorpyrifos concentrations previously reported to diminish olfactory responses (10, 20, and 40 μg/L). While lethality was noted higher doses, measured chlorpyrifos concentrations of 1.38 μg/L (nominal concentration 10 μg/L) significantly reduced the activity of AChE and two serine lipases, monoacylglycerol lipase and fatty acid amide hydrolase in the brain. Reductions in lysophosphatidylethanolamines (16:0; 18:0, 18:1, and 22:6) derived from the phosphatidylethanolamines and free fatty acids (Palmitic acid16:0; Linolenic acid18:3; Eicosadienoic acid 20:2; Arachidonic acid 20:4; and Docosahexaenoic acid 22:6) were also noted, suggesting that chlorpyrifos inhibited the metabolism of selected phospholipid signaling precursors at sublethal concentrations. These results indicate that in addition to AChE inhibition, environmentally relevant chlorpyrifos exposure alters serine lipase activity and lipid metabolites in the trout brain, which may compromise neuronal signaling and impact neurobehavioral responses in aquatic animals.

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 .

Measurement of the ν μ energy spectrum with IceCube-79: IceCube Collaboration

IceCube is a neutrino observatory deployed in the glacial ice at the geographic South Pole. The ν μ 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 ν -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 σ in four adjacent bins for neutrino energies E ν ≥ 177.8 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.

Multiple Sclerosis impact on employment and income in New Zealand

BACKGROUND AND OBJECTIVES

We investigated the demographic, social and clinical characteristics associated with employment status and income for people with multiple sclerosis (MS) in New Zealand (NZ).

METHODS

The NZ National MS Prevalence study included all persons resident in NZ on census day 2006 diagnosed with MS (96.7% coverage). Factors associated with employment and income status among the working age population (25-64 years) were identified by linear regression.

RESULTS

Over 90% of working age people with MS (n=1727) had a work history, but 54% were not working. Work loss occurred early in the disease course, and at low disability (P<.001). Advancing age, progressive disease, longer disease duration, higher disability levels, partner loss and lower education were associated with work loss (P<.001). Working age people with MS had lower income than the NZ population (P<.0001). Higher qualifications yielded no additional income for MS females and about half the additional income for MS males (P<.0001).

CONCLUSIONS

MS profoundly reduces employment and income early in the disease course, and at low levels of disability, however, unemployment is not entirely accounted for by clinical, social and demographic factors. These findings suggest social supports should be explored early in the disease course to reduce loss of income and unemployment for people with MS.

Constraints on Ultrahigh-Energy Cosmic-Ray Sources from a Search for Neutrinos above 10 PeV with IceCube

We report constraints on the sources of ultrahigh-energy cosmic rays (UHECRs) above 10^{9}  GeV, based on an analysis of seven years of IceCube data. This analysis efficiently selects very high- energy neutrino-induced events which have deposited energies from 5×10^{5}  GeV to above 10^{11}  GeV. Two neutrino-induced events with an estimated deposited energy of (2.6±0.3)×10^{6}  GeV, the highest neutrino energy observed so far, and (7.7±2.0)×10^{5}  GeV were detected. The atmospheric background-only hypothesis of detecting these events is rejected at 3.6σ. The hypothesis that the observed events are of cosmogenic origin is also rejected at >99% CL because of the limited deposited energy and the nonobservation of events at higher energy, while their observation is consistent with an astrophysical origin. Our limits on cosmogenic neutrino fluxes disfavor the UHECR sources having a cosmological evolution stronger than the star formation rate, e.g., active galactic nuclei and γ-ray bursts, assuming proton-dominated UHECRs. Constraints on UHECR sources including mixed and heavy UHECR compositions are obtained for models of neutrino production within UHECR sources. Our limit disfavors a significant part of parameter space for active galactic nuclei and new-born pulsar models. These limits on the ultrahigh-energy neutrino flux models are the most stringent to date.

A New Test Phantom for the Evaluation of Doppler Tissue Images

Doppler tissue imaging (DTI) is a technique for examining the motion of moving tissue. It is particularly well suited for the examination of the motion of the myocardium and other cardiac structures. A new DTI test phantom has been designed and constructed that provides the means to evaluate the resolution of DTI images. The phantom consists of a rotating cylinder of tissue mimicking material (TMM) with a sector-shaped cut-out throughout its length. By evaluating the Doppler image of this moving structure, estimates of axial and lateral resolution can be obtained. The phantom was used to make resolution measurements of DTI images on three different ultrasound machines and to assess how machine settings affect resolution. The rotating phantom can also be used to measure contrast resolution, which is velocity resolution when considering DTI mode, and temporal resolution, which is essentially the scanner frame rate in DTI mode.

Searches for Sterile Neutrinos with the IceCube Detector

The IceCube neutrino telescope at the South Pole has measured the atmospheric muon neutrino spectrum as a function of zenith angle and energy in the approximate 320 GeV to 20 TeV range, to search for the oscillation signatures of light sterile neutrinos. No evidence for anomalous ν_{μ} or ν[over ¯]_{μ} disappearance is observed in either of two independently developed analyses, each using one year of atmospheric neutrino data. New exclusion limits are placed on the parameter space of the 3+1 model, in which muon antineutrinos experience a strong Mikheyev-Smirnov-Wolfenstein-resonant oscillation. The exclusion limits extend to sin^{2}2θ_{24}≤0.02 at Δm^{2}∼0.3  eV^{2} at the 90% confidence level. The allowed region from global analysis of appearance experiments, including LSND and MiniBooNE, is excluded at approximately the 99% confidence level for the global best-fit value of |U_{e4}|^{2}.

Effects of Intraosseous Tibial vs. Intravenous Vasopressin in a Hypovolemic Cardiac Arrest Model

Introduction

This study compared the effects of vasopressin via tibial intraosseous (IO) and intravenous (IV) routes on maximum plasma concentration (Cmax), the time to maximum concentration (Tmax), return of spontaneous circulation (ROSC), and time to ROSC in a hypovolemic cardiac arrest model.

Methods

This study was a randomized prospective, between-subjects experimental design. A computer program randomly assigned 28 Yorkshire swine to one of four groups: IV (n=7), IO tibia (n=7), cardiopulmonary resuscitation (CPR) + defibrillation (n=7), and a control group that received just CPR (n=7). Ventricular fibrillation was induced, and subjects remained in arrest for two minutes. CPR was initiated and 40 units of vasopressin were administered via IO or IV routes. Blood samples were collected at 0.5, 1, 1.5, 2, 2.5, 3, and 4 minutes. CPR and defibrillation were initiated for 20 minutes or until ROSC was achieved. We measured vasopressin concentrations using high-performance liquid chromatography.

Results

There was no significant difference between the IO and IV groups relative to achieving ROSC (p=1.0) but a significant difference between the IV compared to the CPR+ defibrillation group (p=0.031) and IV compared to the CPR-only group (p=0.001). There was a significant difference between the IO group compared to the CPR+ defibrillation group (p=0.031) and IO compared to the CPR-only group (p=0.001). There was no significant difference between the CPR + defibrillation group and the CPR group (p=0.127). There was no significant difference in Cmax between the IO and IV groups (p=0.079). The mean ± standard deviation of Cmax of the IO group was 58,709±25, 463pg/mL compared to the IV group, which was 106,198±62, 135pg/mL. There was no significant difference in mean Tmax between the groups (p=0.084). There were no significant differences in odds of ROSC between the tibial IO and IV groups.

Conclusion

Prompt access to the vascular system using the IO route can circumvent the interruption in treatment observed with attempting conventional IV access. The IO route is an effective modality for the treatment of hypovolemic cardiac arrest and may be considered first line for rapid vascular access.

Secondary pool boiling effects

A pool boiling phenomenon referred to as secondary boiling effects is discussed. Based on the experimental trends, a mechanism is proposed that identifies the parameters that lead to this phenomenon. Secondary boiling effects refer to a distinct decrease in the wall superheat temperature near the critical heat flux due to a significant increase in the heat transfer coefficient. Recent pool boiling heat transfer experiments using femtosecond laser processed Inconel, stainless steel, and copper multiscale surfaces consistently displayed secondary boiling effects, which were found to be a result of both temperature drop along the microstructures and nucleation characteristic length scales. The temperature drop is a function of microstructure height and thermal conductivity. An increased microstructure height and a decreased thermal conductivity result in a significant temperature drop along the microstructures. This temperature drop becomes more pronounced at higher heat fluxes and along with the right nucleation characteristic length scales results in a change of the boiling dynamics. Nucleation spreads from the bottom of the microstructure valleys to the top of the microstructures, resulting in a decreased surface superheat with an increasing heat flux. This decrease in the wall superheat at higher heat fluxes is reflected by a "hook back" of the traditional boiling curve and is thus referred to as secondary boiling effects. In addition, a boiling hysteresis during increasing and decreasing heat flux develops due to the secondary boiling effects. This hysteresis further validates the existence of secondary boiling effects.