scholarly journals Bayesian constraints on the astrophysical neutrino source population from IceCube data

2020 ◽  
Vol 101 (12) ◽  
Author(s):  
F. Capel ◽  
D. J. Mortlock ◽  
C. Finley
Keyword(s):  
Source Population ◽  
Neutrino Source ◽  
Astrophysical Neutrino

scholarly journals IceCube: An overview of physics results

2019 ◽  
Vol 207 ◽  
pp. 01002
Author(s):  
Ignacio Taboada
Keyword(s):  
Cosmic Rays ◽  
Real Time ◽  
Milky Way ◽  
Neutrino Flux ◽  
Point Sources ◽  
Neutrino Source ◽  
Potential Sources ◽  
Astrophysical Neutrinos ◽  
Astrophysical Neutrino

Cosmic rays and neutrinos are intimately related. And though TeVPeV astrophysical neutrinos have been observed, their sources and their relation to potential sources of cosmic rays remain unknown. Recently, the blazar TXS 0506+056 has been identified as a candidate neutrino source. In parallel, IceCube has conducted numerous searches for other potential neutrino neutrino sources. These proceedings are limited in scope, given the large breath of science results by IceCube: A description of the astrophysical neutrino flux; a review of the real-time program that enables multi-messenger follow-up of neutrinos; a summary of the observations of TXS 0506+056; a recap of the search for neutrino point sources with 7 years of IceCube data; an account of the tantalizing capabilities of IceCube and ANTARES to detect Milky Way neutrinos and a description of a method to identify Glashow resonance events.

scholarly journals INTRINSIC AND OSCILLATED ASTROPHYSICAL NEUTRINO FLAVOR RATIOS REVISITED

2006 ◽  
Vol 21 (13) ◽  
pp. 1049-1065 ◽  
Author(s):  
H. ATHAR ◽  
C. S. KIM ◽  
JAKE LEE
Keyword(s):  
Neutrino Oscillations ◽  
Muon Neutrinos ◽  
Neutrino Source ◽  
Tau Neutrinos ◽  
Neutrino Flavor ◽  
Astrophysical Neutrinos ◽  
Astrophysical Neutrino

The pp interactions taking place in the cosmos around us are a source of the astrophysical neutrinos of all the three flavors. In these interactions, the electron and the muon neutrinos mainly come from the production and the decay of the π± mesons, whereas the tau neutrinos mainly come from the production and the decay of the [Formula: see text] mesons. We estimate the three intrinsic neutrino flavor ratios for 1 GeV ≤E≤1012 GeV in the pp interactions and found them to be 1:2:3×10-5. We study the effects of neutrino oscillations on these intrinsic ratios. We point out that the three ratios become 1:1:1 if L (pc)/E(GeV) ≥10-10 in the presence of neutrino oscillations, where L is the distance to the astrophysical neutrino source in units of parsecs.

Investigation of 18 physiologically dormant Australian native species: germination response, environmental correlations and the implications for conservation

2020 ◽  
pp. 1-9
Author(s):  
Justin C. Collette ◽  
Mark K.J. Ooi
Keyword(s):  
Native Species ◽  
Strong Dependence ◽  
Ex Situ ◽  
Source Population ◽  
Seasonal Temperature ◽  
Environmental Correlations ◽  
Rainfall Season ◽  
Germination Response ◽  
Rainfall Seasonality ◽  
Germination Experiments

Abstract For physiologically dormant (PD) species in fire-prone environments, dormancy can be both complex due to the interaction between fire and seasonal cues, and extremely deep due to long intervals between recruitment events. Due to this complexity, there are knowledge gaps particularly surrounding the dormancy depth and cues of long-lived perennial PD species. This can be problematic for both in situ and ex situ species management. We used germination experiments that tested seasonal temperature, smoke, dark and heat for 18 PD shrub species distributed across temperate fire-prone Australia and assessed how germination was correlated with environmental factors associated with their home environments. We found extremely high levels of dormancy, with only eight species germinating above 10% and three species producing no germination at all. Seven of these eight species had quite specific seasonal temperature requirements and/or very strong responses to smoke cues. The maximum germination for each species was positively correlated with the mean temperature of the source population but negatively correlated with rainfall seasonality and driest months. The strong dependence on a smoke cue for some of the study species, along with examples from other studies, provides evidence that an obligate smoke response could be a fire-adapted germination cue. Germination response correlated with rainfall season of the source populations is a pattern which has often been assumed but little comparative data across sites with different rainfall seasonality exists. Further investigation of a broader range of species from different rainfall season environments would help to elucidate this knowledge gap.

Using novel methodologies to support burden of disease estimates

2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
T Hald
Keyword(s):  
International Development ◽  
Traditional Approach ◽  
Source Population ◽  
Surveillance Systems ◽  
Data Generation ◽  
Time Data ◽  
African Countries ◽  
Indirect Measure ◽  
True Incidence ◽  
Laboratory Capacity

Abstract A challenge to estimating burden of diarrheal diseases, particularly in LMICs, where laboratory capacity and surveillance systems are limited, is obtaining valid estimates of etiology proportions of cases. A commonly used method is systematic review of studies reporting pathogen isolation in diarrhea cases. However, studies often differ in design, source population, timeframe, and pathogens included, hampering extrapolation to the target population. In a study co-funded by the Bill and Melinda Gates Foundation and the UK Department for International Development, we explore a novel approach for estimating diarrhea etiology proportions in urban and rural populations in four African countries. We analyse sewage samples using short-read next-generation sequencing (NGS) to determine abundance of genes that can be mapped to specific bacterial genera, providing an estimate of the relative abundance of specific pathogens in each sample. In parallel to collecting sewage samples, a questionnaire-based population survey will estimate diarrheal incidence. By combining results, pathogen-specific incidence will be estimated and compared with incidence estimates from the traditional approach. The application NGS to human sewage has great potential for surveillance of foodborne infections, particularly in resource-poor settings where laboratory capacity for bacterial isolation is limited. First, NGS is a one method takes all approach, as it is based on detection of RNA/DNA, a language common across pathogens. Second, it is culture independent, allowing for real-time data generation and standardized sharing. Finally, few samples are needed to survey large populations for several pathogens at the same time. Thus, surveillance based on NGS of sewage may prove to be an indirect measure of incidence. Although it will not provide an estimate for the true incidence in the population, it will increase our understanding of the burden and as such be a proxy and novel way of ranking diseases.

scholarly journals Effect of first-line biologic initiation on glucocorticoid exposure in children hospitalized with new-onset systemic juvenile idiopathic arthritis: emulation of a pragmatic trial using observational data

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Rosemary G. Peterson ◽  
Rui Xiao ◽  
Hannah Katcoff ◽  
Brian T. Fisher ◽  
Pamela F. Weiss
Keyword(s):  
Juvenile Idiopathic Arthritis ◽  
Biologic Therapy ◽  
Tertiary Care ◽  
Pragmatic Trial ◽  
Systemic Juvenile Idiopathic Arthritis ◽  
Source Population ◽  
First Line ◽  
Eligibility Criteria ◽  
Over Time ◽  
New Onset

Abstract Background Glucocorticoid exposure is a significant driver of morbidity in children with systemic juvenile idiopathic arthritis (sJIA). We determined the effect of early initiation of biologic therapy (IL-1 or IL-6 inhibition) on glucocorticoid exposure in hospitalized patients with new-onset sJIA. Methods We emulated a pragmatic sequence of trials (“pseudo-trials”) of biologic initiation in children (≤ 18 years) hospitalized with new-onset sJIA utilizing retrospective data from an administrative database from 52 tertiary care children’s hospitals from 2008 to 2019. Eligibility window, treatment assignment and start of follow-up between biologic and non-biologic study arms were aligned for each pseudo-trial. Patients in the source population could meet eligibility criteria at several timepoints. Mixed-effects logistic regression was used to determine the effect of biologic initiation on in-hospital glucocorticoid exposure. Results Four hundred sixty-eight children met eligibility criteria, of which 19% received biologic therapy without preceding or concomitant initiation of immunomodulatory medications. This proportion significantly increased over time during the study period (p <  0.01). 1451 trial subjects were included across 4 pseudo-trials with 71 assigned to the biologic arm and 1380 assigned to the non-biologic arm. After adjustment, there was a trend toward decreased odds of glucocorticoid initiation in the biologic arm compared to the non-biologic arm (OR 0.39, 95% CI [0.13, 1.15]). Conclusion Biologic initiation in children hospitalized with new-onset sJIA significantly increased over time and may be associated with reduced glucocorticoid exposure. The increasing use of first-line biologic therapy may lead to clinically relevant reductions in treatment-related adverse effects of glucocorticoid-reliant therapeutic approaches.

scholarly journals Contributions of source population and incubation temperature to phenotypic variation of hatchling Chinese skinks

2020 ◽  
Author(s):  
Hong-Liang Lu ◽  
Yan-Fu Qu ◽  
Hong Li ◽  
Xiang Ji
Keyword(s):  
Body Mass ◽  
Phenotypic Variation ◽  
Incubation Temperature ◽  
Tail Length ◽  
Population Variation ◽  
Phenotypic Traits ◽  
Source Population ◽  
Relative Importance ◽  
The Difference ◽  
Hatchling Size

Abstract Phenotypic plasticity and local adaptation are viewed as the main factors that result in between-population variation in phenotypic traits, but contributions of these factors to phenotypic variation vary between traits and between species and have only been explored in a few species of reptiles. Here, we incubated eggs of the Chinese skink (Plestiodon chinensis) from 7 geographically separated populations in Southeast China at 3 constant temperatures (24, 28, and 32 °C) to evaluate the combined effects of clutch origin, source population, and incubation temperature on hatchling traits. The relative importance of these factors varied between traits. Nearly all examined hatchling traits, including body mass, snout–vent length (SVL), tail length, head size, limb length, tympanum diameter, and locomotor speed, varied among populations and were affected by incubation temperature. Measures for hatchling size (body mass and SVL) varied considerably among clutches. Source population explained much of the variation in hatchling body mass, whereas incubation temperature explained much of the variation in other examined traits. Our results indicate that between-population variation in hatchling traits of P. chinensis likely reflects the difference in natural incubation conditions and genetic divergence.

scholarly journals Preparing for translocations of a Critically Endangered petrel through targeted monitoring of nest survival and breeding biology

Oryx ◽  
2021 ◽  
pp. 1-9
Author(s):  
Johannes H. Fischer ◽  
Heiko U. Wittmer ◽  
Graeme A. Taylor ◽  
Igor Debski ◽  
Doug P. Armstrong
Keyword(s):  
Southern Oscillation ◽  
Nest Survival ◽  
Growth Curves ◽  
Breeding Biology ◽  
Source Population ◽  
Breeding Phenology ◽  
Chick Survival ◽  
Egg Survival ◽  
Dune System ◽  
Burrow Density

Abstract The population of the recently-described Whenua Hou diving petrel Pelecanoides whenuahouensis comprises c. 200 adults that all breed in a single 0.018 km2 colony in a dune system vulnerable to erosion. The species would therefore benefit from the establishment of a second breeding population through a translocation. However, given the small size of the source population, it is essential that translocations are informed by carefully targeted monitoring data. We therefore modelled nest survival at the remaining population in relation to potential drivers (distance to sea and burrow density of conspecifics and a competitor) across three breeding seasons with varying climatic conditions as a result of the southern oscillation cycle. We also documented breeding phenology and burrow attendance, and measured chicks, to generate growth curves. We estimated egg survival at 0.686, chick survival at 0.890, overall nest survival at 0.612, and found no indication that nest survival was affected by distance to sea or burrow density. Whenua Hou diving petrels laid eggs in mid October, eggs hatched in late November, and chicks fledged in mid January at c. 86% of adult weight. Burrow attendance (i.e. feeds) decreased from 0.94 to 0.65 visits per night as chicks approached fledging. Nest survival and breeding biology were largely consistent among years despite variation in climate. Nest survival estimates will facilitate predictions about future population trends and suitability of prospective translocation sites. Knowledge of breeding phenology will inform the timing of collection of live chicks for translocation, and patterns of burrow attendance combined with growth curves will structure hand-rearing protocols. A tuhinga whakarāpopoto (te reo Māori abstract) can be found in the Supplementary material.

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