Measuring eccentricity in binary black hole inspirals with gravitational waves

When binary black holes form in the field, it is expected that their orbits typically circularize before coalescence. In galactic nuclei and globular clusters, binary black holes can form dynamically. Recent results suggest that $\approx5\%$ of mergers in globular clusters result from three-body interactions. These three-body interactions are expected to induce significant orbital eccentricity $\gtrsim 0.1$ when they enter the Advanced LIGO band at a gravitational-wave frequency of 10 Hz. Measurements of binary black hole eccentricity therefore provide a means for determining whether or not dynamic formation is the primary channel for producing binary black hole mergers. We present a framework for performing Bayesian parameter estimation on gravitational-wave observations of black hole inspirals. Using this framework, and employing the non-spinning, inspiral-only EccentricFD waveform approximant, we determine the minimum detectable eccentricity for an event with masses and distance similar to GW150914. At design sensitivity, we find that the current generation of advanced observatories will be sensitive to orbital eccentricities of $\gtrsim0.05$ at a gravitational-wave frequency of 10 Hz, demonstrating that existing detectors can use eccentricity to distinguish between circular field binaries and globular cluster triples. We compare this result to eccentricity distributions predicted to result from three black hole binary formation channels, showing that measurements of eccentricity could be used to infer the population properties of binary black holes.Comment: 12 pages, 7 figures, 2 table

Fullerene van der waals Oligomers as electron traps

Density functional theory calculations indicate that van der Waals fullerene dimers and larger oligomers can form interstitial electron traps in which the electrons are even more strongly bound than in isolated fullerene radical anions. The fullerenes behave like super atoms , and the interstitial electron traps represent one-electron intermolecular σ-bonds. Spectroelectrochemical measurements on a bis-fullerene-substituted peptide provide experimental support. The proposed deep electron traps are relevant for all organic electronics applications in which non-covalently linked fullerenes in van der Waals contact with one another serve as n-type semiconductors

A conceptual design study of the reusable reentry satellite

Experimentation leading to an understanding of life processes under reduced and extremely low gravitational forces will profoundly contribute to the success of future space missions involving humans. In addition to research on gravitational biology, research on the effects of cosmic radiation and the interruption and change of circadian rhythms on life systems is also of prime importance. Research in space, however, is currently viewed by biological scientists as an arena that is essential, yet largely inaccessible to them for their experimentation. To fulfill this need, a project and spacecraft system described as the Reusuable Reentry Satellite or Lifesat has been proposed by NASA

The incidence of low venous oxygen saturation on admission to the intensive care unit: a multi-center observational study in The Netherlands

Background Low mixed or central venous saturation (S(c)vO(2)) can reveal global tissue hypoxia and therefore can predict poor prognosis in critically ill patients. Early goal directed therapy (EGDT), aiming at an ScvO(2) >= 70%, has been shown to be a valuable strategy in patients with sepsis or septic shock and is incorporated in the Surviving Sepsis Campaign guidelines. Methods In this prospective observational multi-center study, we determined central venous pressure (CVP), hematocrit, pH, lactate and ScvO(2) or SvO(2) in a heterogeneous group of critically ill patients early after admission to the intensive care units (ICUs) in three Dutch hospitals. Results Data of 340 acutely admitted critically ill patients were collected. The mean SvO(2) value was > 65% and the mean ScvO(2) value was > 70%. With mean CVP of 10.3 +/- 5.5 mmHg, lactate plasma levels of 3.6 +/- 3.6 and acute physiology, age and chronic health evaluation (APACHE II) scores of 21.5 +/- 8.3, the in-hospital mortality of the total heterogeneous population was 32.0%. A subgroup of septic patients (n = 125) showed a CVP of 9.8 +/- 5.4 mmHg, mean ScvO(2) values of 74.0 +/- 10.2%, where only 1% in this subgroup revealed a ScvO(2) value <50%, and lactate plasma levels of 2.7 +/- 2.2 mmol/l with APACHE II scores 20.9 +/- 7.3. Hospital mortality of this subgroup was 26%. Conclusion The incidence of low ScvO(2) values for acutely admitted critically ill patients is low in Dutch ICUs. This is especially true for patients with sepsis/septic shock

Framing and visual type: Effect on future Zika vaccine uptake intent

Introduction: The Zika virus is associated with the birth defect microcephaly, and while a vaccine was not available in early- 2017, several were under development. This study’s purpose was to identify effective communication strategies to promote uptake of a new vaccine, particularly among women of reproductive age.Design and methods: In order to study the effects of Zika message framing (gain vs. loss) and visual type (photo vs. infographic) on future Zika vaccine uptake intent, a 2×2 between-subjects experiment was performed via an online survey in 2017 among 339 U.S. women of reproductive age (18-49 years). Participants were exposed to one of four messages, all resembling Instagram posts: gain-framed vs. loss-framed infographic, and gain-framed vs. loss-framed photo. These messages were followed by questions about Zika vaccine uptake intent as well as intermediate psychosocial variables that could lead to intent. Results: There was no interaction between framing and visual type (P=0.116), and there was no effect for framing (P=0.185) or visual type (P=0.724) on future Zika vaccine uptake intent, which is likely indicative of insufficient dosage of the intervention. However, when focusing on intermediate psychosocial constructs that are known to influence behavior and intent, gain-framed messages were more effective in increasing subjective norms (P=0.005) as related to a future Zika vaccine, as well as perceived benefits (P=0.016) and self-efficacy (P=0.032). Conclusions: Gain-framed messages seem to be more effective than loss-framed messages to increase several constructs that could, in turn, affect future Zika vaccine uptake intent. This is a novel finding since, traditionally, loss-framed messages are considered more beneficial in promoting vaccine-related health behaviors

Wild African Drosophila melanogaster are seasonal specialists on marula fruits

Although the vinegar fly Drosophila melanogaster isarguably the most studied organism on the planet,fundamental aspects of this species’ natural ecologyhave remained enigmatic [1]. We have here investigateda wild population of D. melanogaster from amopane forest in Zimbabwe. We find that these fliesare closely associated with marula fruit (Sclerocaryabirrea) and propose that this seasonally abundantand predominantly Southern African fruit is a keyancestral host of D. melanogaster. Moreover, whenfruiting, marula is nearly exclusively used byD. melanogaster, suggesting that these forest-dwellingD. melanogaster are seasonal specialists, in asimilar manner to, e.g., Drosophila erecta on screwpine cones [2]. We further demonstrate that themain chemicals released by marula activate odorantreceptors that mediate species-specific host choice(Or22a) [3, 4] and oviposition site selection (Or19a)[5]. The Or22a-expressing neurons—ab3A—respondstrongly to the marula ester ethyl isovalerate, a volatilerarely encountered in high amounts in other fruit.We also show that Or22a differs among African populationssampled from a wide range of habitats, inline with a function associated with host fruit usage.Flies from Southern Africa, most of which carry adistinct allele at the Or22a/Or22b locus, have ab3Aneurons that are more sensitive to ethyl isovaleratethan, e.g., European flies. Finally, we discuss thepossibility that marula, which is also a culturallyand nutritionally important resource to humans,may have helped the transition to commensalism inD. melanogaster

Should exercises be painful in the management of chronic musculoskeletal pain?: a systematic review and meta-analysis

Background: Chronic musculoskeletal disorders are a prevalent and costly global health issue. A new form of exercise therapy focused on loading and resistance programmes that temporarily aggravates a patient’s pain has been proposed. The object of this review was to compare the effect of exercises where pain is allowed/encouraged, compared with non-painful exercises on pain, function or disability in patients with chronic musculoskeletal pain within randomised controlled trials. Methods: Two authors independently selected studies and appraised risk of bias. Methodological quality was evaluated using the Cochrane risk of bias tool and the GRADE system was used to evaluate the quality of evidence. Results: The literature search identified 9,081 potentially eligible studies. Nine papers (from seven trials) with 385 participants met the inclusion criteria. There was short term significant difference in pain, with moderate quality evidence for a small effect size of -0.27 (-0.54 to -0.05) in favour of painful exercises. For pain at medium and long term; and function and disability at short, medium and long term there was no significant difference. Conclusion: Protocols using painful exercises offer a small, but significant benefit over pain-free exercises at short term, with moderate quality of the evidence. At medium and long term there is no clear superiority of one treatment over another. Pain during therapeutic exercise for chronic musculoskeletal pain need not be a barrier to successful outcomes. Further research is warranted to fully evaluate the effectiveness of loading and resistance programmes into pain for chronic musculoskeletal disorders. PROSPERO Registration: CRD4201603888

Collision statistics in sheared inelastic hard spheres

The dynamics of sheared inelastic-hard-sphere systems are studied using non-equilibrium molecular dynamics simulations and direct simulation Monte Carlo. In the molecular dynamics simulations Lees-Edwards boundary conditions are used to impose the shear. The dimensions of the simulation box are chosen to ensure that the systems are homogeneous and that the shear is applied uniformly. Various system properties are monitored, including the one-particle velocity distribution, granular temperature, stress tensor, collision rates, and time between collisions. The one-particle velocity distribution is found to agree reasonably well with an anisotropic Gaussian distribution, with only a slight overpopulation of the high velocity tails. The velocity distribution is strongly anisotropic, especially at lower densities and lower values of the coefficient of restitution, with the largest variance in the direction of shear. The density dependence of the compressibility factor of the sheared inelastic hard sphere system is quite similar to that of elastic hard sphere fluids. As the systems become more inelastic, the glancing collisions begin to dominate more direct, head-on collisions. Examination of the distribution of the time between collisions indicates that the collisions experienced by the particles are strongly correlated in the highly inelastic systems. A comparison of the simulation data is made with DSMC simulation of the Enskog equation. Results of the kinetic model of Montanero et al. {[}Montanero et al., J. Fluid Mech. 389, 391 (1999){]} based on the Enskog equation are also included. In general, good agreement is found for high density, weakly inelastic systems.Comment: 10 figures, 1 table, 27 page

The experience of living with patellofemoral pain: loss, confusion and fear-avoidance: a UK qualitative study

Objectives: To investigate the experience of living with patellofemoral pain. Design: Qualitative study design using semi-structured interviews, and analysed thematically using the guidelines set out by Braun and Clarke. Setting: A National Health Service (NHS) physiotherapy clinic within a large UK teaching hospital. Participants: A convenience sample of ten participants, aged between 18 and 40, with a diagnosis of patellofemoral pain and on a physiotherapy waiting list, prior to starting physiotherapy. Results: Participants offered rich and detailed accounts of the impact and lived experience of patellofemoral pain, including: loss of physical and functional ability; loss of self - identity; pain related confusion and difficulty making sense of their pain ; pain related fear, including fear -avoidance and ‘damage’ beliefs; inappropriate coping strategies and fear of the future. The five major themes that emerged from the data were: (1) impact on self; (2) uncertainty, confusion and sense making; (3) exercise and activity beliefs; (4) behavioural coping strategies and (5) expectations of the future. Conclusions: These findings offer an insight into the lived experience of individuals with patellofemoral pain. Previous literature ha s focused on pain and biomechanics, rather than the individual experience, attached meanings and any wider context within a sociocultural perspective. Our findings suggest future research is warranted into biopsychosocial targeted interventions aimed at the beliefs and pain related fear for people with patellofemoral pain. The current consensus that best - evidence treatments consisting of hip and knee strengthening may not be adequate to address the fears and beliefs identified in the current study. Further qualitative research may be warranted on the impact and interpretation of medical terminology commonly used with this patient group, for example, ‘weakness’ and ‘patellar mal-tracking’ and its impact and interpretation by patients

Discrepancy in exchangeable and soluble ammonium-induced effects on aerobic methane oxidation: a microcosm study of a paddy soil

Ammonium-induced stimulatory, inhibitory, and/or neutral effects on soil methane oxidation have been attributable to the ammonium concentration and mineral forms, confounded by other edaphic properties (e.g., pH, salinity), as well as the site-specific composition of the methanotrophic community. We hypothesize that this inconsistency may stem from the discrepancy in the cation adsorption capacity of the soil. We postulate that the effects of ammonium on the methanotrophic activity in soil are more accurately portrayed by relating methane uptake rates to the soluble ammonium (bioavailable), rather than the exchangeable (total) ammonium. To reduce adsorption (exchangeable) sites for ammonium in a paddy soil, two successive pre-incubation steps were introduced resulting in a 1000-fold soil dilution (soil enrichment), to be compared to a soil slurry (tenfold dilution) incubation. Ammonium was supplemented as NH4Cl at 0.5–4.75gL−1 after pre-incubation. While NH4Cl significantly stimulated the methanotrophic activity at all concentrations in the soil slurry incubation, methane uptake showed a dose-dependent effect in the soil enrichment. The trend in methane uptake could be explained by the soluble ammonium concentration, which was proportionate to the supplemented ammonium in the soil enrichment. In the soil slurry incubation, a fraction (36–63%) of the supplemented ammonium was determined to be adsorbed to the soil. Accordingly, Methylosarcina was found to predominate the methanotrophic community after the incubation, suggesting the relevance of this methanotroph at elevated ammonium levels (< 3.25gL−1 NH4Cl). Collectively, our results showed that the soluble, rather than the exchangeable ammonium concentration, is relevant when determining the effects of ammonium on methane oxidation, but this does not exclude other (a)biotic factors concurrently influencing methanotrophic activity