Hyperbolic limit on the early arrival time of bright pulses from PSR~J0835−-4510 (Vela)

Astronomers have studied the Vela pulsar (PSR~J0835$-$4510) for decades. This study analyses almost one hundred hours of single-pulse data collected over three consecutive days from 2016 and 2020. The work investigates the fascinating phenomena of the earlier arrival of brighter pulses with their increase in peak intensity. We found a hyperbolic relation between them by constructing integrated pulse profiles using flux density intervals and examining the relationship between pulse arrival time and intensity. We identified a phase limit of $-0.85~\pm 0.0109$~ms for the earliest arrival of the brightest pulses. This study offers exciting prospects for further exploring the emission regions responsible for the Vela pulsar's regular and giant micro-pulses.Comment: 9 pages, 11 figure

Trends in method-specific suicide in Brazil from 2000 to 2017

Purpose: Understanding long-term patterns of suicide methods can inform public health policy and prevention strategies. In Brazil, firearm-related policies may be one salient target for suicide prevention. This study describes trends in method-specific suicide at the national and state-levels in Brazil, with a particular focus on firearm-related suicides. / Methods: Brazilian mortality data for suicide and undetermined intent among people aged 10 years and older between 2000 and 2017 were obtained from the National Mortality Information System. We examined national and state-level trends in age-standardised suicide rates for hanging, self-poisoning, firearms, jumping from a high place, other, and unspecified methods. We also compared total rates of mortality from suicide and undetermined intent over the period. Applying Joinpoint regression, we tested changes in trends of firearm-specific suicide rates. / Results: The total suicide rate increased between 2000 and 2017. Rates of hanging, self-poisoning by drugs or alcohol and jumping from a high place showed the largest increases, while firearm-specific suicide rates decreased over the study period. Trends in methods of suicide varied by sex and state. / Conclusion: It is of public health concern that suicide rates in Brazil have risen this millennium. Restricting access to firearms might be an effective approach for reducing firearm-specific suicides, especially in states where firearm availability remains particularly high. Treatment and management of substance misuse may also be an important target for suicide prevention policies. More work is needed to understand the causes of rising suicide rates in Brazil and to improve the mental health of the population

Ultra-High Resolution Intensity Statistics of a Scintillating Source

We derive the distribution of flux density of a compact source exhibiting strong diffractive scintillation. Our treatment accounts for arbitrary spectral averaging, spatially-extended source emission, and the possibility of intrinsic variability within the averaging time, as is typical for pulsars. We also derive the modulation index and present a technique for estimating the self-noise of the distribution, which can be used to identify amplitude variations on timescales shorter than the spectral accumulation time. Our results enable a for direct comparison with ultra-high resolution observations of pulsars, particularly single-pulse studies with Nyquist-limited resolution, and can be used to identify the spatial emission structure of individual pulses at a small fraction of the diffractive scale.Comment: 14 Pages, 4 Figures, accepted for publication in Ap

Burkholderia cenocepacia ET12 strain activates TNFR1 signalling in cystic fibrosis airway epithelial cells

Burkholderia cenocepacia is an important pulmonary pathogen in individuals with cystic fibrosis (CF). Infection is often associated with severe pulmonary inflammation, and some patients develop a fatal necrotizing pneumonia and sepsis (‘cepacia syndrome’). The mechanisms by which this species causes severe pulmonary inflammation are poorly understood. Here, we demonstrate that B. cenocepacia BC7, a potentially virulent representative of the epidemic ET12 lineage, binds to tumour necrosis factor receptor 1 (TNFR1) and activates TNFR1-related signalling pathway similar to TNF-α, a natural ligand for TNFR1. This interaction participates in stimulating a robust IL-8 production from CF airway epithelial cells. In contrast, BC45, a less virulent ET12 representative, and ATCC 25416, an environmental B. cepacia strain, do not bind to TNFR1 and stimulate only minimal IL-8 production from CF cells. Further, TNFR1 expression is increased in CF airway epithelial cells compared with non-CF cells. We also show that B. cenocepacia ET12 strain colocaizes with TNFR1 in vitro and in the lungs of CF patients who died due to infection with B. cenocepacia, ET12 strain. Together, these results suggest that interaction of B. cenocepacia , ET12 strain with TNFR1 may contribute to robust inflammatory responses elicited by this organism.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73011/1/j.1462-5822.2007.01029.x.pd

Developing a questionnaire to determine the impact of self-management in diabetes: giving people with diabetes a voice

Background The prevalence of diabetes mellitus (DM) is increasing dramatically, placing considerable financial burden on the healthcare budget of each country. Patient self-management is crucial for the control of blood glucose, which largely determines the chances of developing diabetes-related complications. Self-management interventions vary widely, and a method is required for assessing the impact of self-management. This paper describes the development of a questionnaire intended for use to measure the impact of self-management in diabetes. Methods An iterative development process was undertaken to identify the attributes of self-management using 5 steps. First, a literature review was undertaken to identify and understand themes relating to self-management of DM to inform a topic guide. Second, the topic guide was further refined following consultation with a Patient and Public Involvement group. Third, the topic guide was used to inform semi-structured interviews with patients with Type 1 DM (T1DM) and Type 2 DM (T2DM) to identify how self-management of DM affects individuals. Fourth, the research team considered potential attributes alongside health attributes from an existing measure (Diabetes Health Profile, DHP) to produce an instrument reflecting both health and self-management outcomes simultaneously. Finally, a draft instrument was tested in a focus group to determine the wording and acceptability. Results Semi-structured interviews were carried out with 32 patients with T1DM and T2DM. Eight potential attributes were identified: fear/worry/anxiety, guilt, stress, stigma, hassle, control, freedom, and feeling supported. Four of these self-management attributes were selected with four health attributes (mood, worry about hypos (hypoglycaemic episodes), vitality and social limitations) to produce the Health and Self-Management in Diabetes (HASMID v1) questionnaire. Conclusions HASMID v1 is a short questionnaire that contains eight items each with four response levels to measure the impact of self-management in diabetes for both T1DM and T2DM. The measure was developed using a mixed-methods approach that involved semi-structured interviews with people with diabetes. The measure has high face validity. Ongoing research is being undertaken to assess the validity of this questionnaire for measuring the impact of self-management interventions in economic evaluation

Detection of Gamma-Ray Emission from the Vela Pulsar Wind Nebula with AGILE

Pulsars are known to power winds of relativistic particles that can produce bright nebulae by interacting with the surrounding medium. These pulsar wind nebulae (PWNe) are observed in the radio, optical, x-rays and, in some cases, also at TeV energies, but the lack of information in the gamma-ray band prevents from drawing a comprehensive multiwavelength picture of their phenomenology and emission mechanisms. Using data from the AGILE satellite, we detected the Vela pulsar wind nebula in the energy range from 100 MeV to 3 GeV. This result constrains the particle population responsible for the GeV emission, probing multivavelength PWN models, and establishes a class of gamma-ray emitters that could account for a fraction of the unidentified Galactic gamma-ray sources.Comment: Accepted by Science; first published online on December 31, 2009 in Science Express. Science article and Supporting Online Material are available at http://www.sciencemag.or

Unraveling acetogen gas fermentation using quantitative systems biology

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