Abstract
We investigate an interacting dark sector scenario in which the vacuum energy is free to interact with cold dark matter (CDM), which itself is assumed to cluster under the sole action of ...gravity, i.e. it is in freefall (geodesic), as in ΛCDM. The interaction is characterized by a dimensionless coupling qV(z), in general a function of redshift. Aiming to reconstruct the evolution of the coupling, we use cosmic microwave background data from Planck 2015, along with baryon acoustic oscillation, redshift space distortion, and Type Ia supernova measurements to constrain various parametrizations of qV(z). We present the full linear perturbation theory of this interacting scenario and use Monte Carlo Markov Chains (MCMC) sampling to study five different cases: two cases in which we have ΛCDM evolution in the distant past, until a set redshift ztrans, below which the interaction switches on and qV is the single-sampled parameter, with ztrans fixed at ztrans = 3000 and 0.9, respectively; a case where we allow this transition redshift to vary along with qV; a case in which the vacuum energy is zero for z > ztrans and then begins to grow once the interaction switches on; and the final case in which we bin qV(z) in four redshift bins to investigate the possibility of a dynamical interaction, reconstructing the redshift evolution of the function using Gaussian processes. We find that, in all cases where the high-redshift evolution is not modified, the results are compatible with a vanishing coupling, thus finding no significant deviation from ΛCDM.
This study examined the evolution of physical and technical soccer performance across a 7-season period in the English Premier League. Match performance observations (n=14 700) were analysed for ...emergent trends. Total distance covered during a match was ~2% lower in 2006-07 compared to 2012-13. Across 7 seasons, high-intensity running distance and actions increased by ~30% (890±299 vs. 1 151±337 m, p<0.001; ES: 0.82) and ~50% (118±36 vs. 176±46, p<0.001; ES: 1.41), respectively. Sprint distance and number of sprints increased by ~35% (232±114 vs. 350±139 m, p<0.001; ES: 0.93) and ~85% (31±14 vs. 57±20, p<0.001; ES: 1.46), respectively. Mean sprint distance was shorter in 2012-13 compared to 2006-07 (5.9±0.8 vs. 6.9±1.3 m, p<0.001; ES: 0.91), with the proportion of explosive sprints increasing (34±11 vs. 47±9%, p<0.001; ES: 1.31). Players performed more passes (35±17 vs. 25±13, p<0.001; ES: 0.66) and successful passes (83±10% vs. 76±13%, p<0.001; ES: 0.60) in 2012-13 compared to 2006-07. Whereas the number of short and medium passes increased across time (p<0.001; ES>0.6), the number of long passes varied little (p<0.001; ES: 0.11). This data demonstrates evolution of physical and technical parameters in the English Premier League, and could be used to aid talent identification, training and conditioning preparation.
Food web ecologists have long sought to characterize the trophic niches of animals using stable isotopic analysis. However, distilling trophic position from isotopic composition has been difficult, ...largely because of the variability associated with trophic discrimination factors (inter-trophic isotopic fractionation and routing). We circumvented much of this variability using compound-specific isotopic analysis (CSIA). We examined the (15)N signatures of amino acids extracted from organisms reared in pure culture at four discrete trophic levels, across two model communities. We calculated the degree of enrichment at each trophic level and found there was a consistent trophic discrimination factor (~7.6‰). The constancy of the CSIA-derived discrimination factor permitted unprecedented accuracy in the measurement of animal trophic position. Conversely, trophic position estimates generated via bulk-(15)N analysis significantly underestimated trophic position, particularly among higher-order consumers. We then examined the trophic hierarchy of a free-roaming arthropod community, revealing the highest trophic position (5.07) and longest food chain ever reported using CSIA. High accuracy in trophic position estimation brings trophic function into sharper focus, providing greater resolution to the analysis of food webs.
IntroductionThis umbrella review is the frst to systematically examine psychological trauma as a transdiagnostic risk factor across psychiatric conditions.ObjectivesThis review aimed to be the frst ...to evaluate whether psychological trauma fulflilled criteria as a transdiagnostic risk factor cutting across various diagnostic categories and spectra. Transdiagnosticity will be assessed against the framework of the TRANSD criteria (Fusar-Poli, World Psychiatry 2019; 18 361-362). The paper additionally aimed to analyse the association of psychopathology with specifc trauma type.MethodsWe searched Pubmed, Scopus, and PsycNET databases from inception until 01/05/2021 for systematic reviews/meta-analyses evaluating the association between psychological trauma and at least one diagnosed mental disorder. We re-calculated the odds ratio (OR), then classifed the association as convincing, highly suggestive, suggestive, or weak, based on the number of cases and controls with and without psychological trauma, random-efects p value, the 95% conf- dence interval of the largest study, heterogeneity between studies, 95% prediction interval, small-study efect, and excess significance bias. Additional outcomes were the association between specifc trauma types and specific mental disorders, and a sensitivity analysis for childhood trauma. Transdiagnosticity was assessed using TRANSD criteria. The review was pre-registered in Prospero CRD42020157308 and followed PRISMA/MOOSE guidelines.ResultsFourteen reviews met inclusion criteria, comprising 16,277 cases and 77,586 controls. Psychological trauma met TRANSD criteria as a transdiagnostic factor across diferent diagnostic criteria and spectra. There was highly suggestive evidence of an association between psychological trauma at any time-point and any mental disorder (OR=2.92) and between childhood trauma and any mental disorder(OR=2.90). Regarding specifc trauma types, convincing evidence linked physical abuse (OR=2.36) and highly suggestive evidence linked sexual abuse (OR=3.47) with a range of mental disorders, and convincing evidence linked emotional abuse to anxiety disorders (OR=3.05); there were no data for emotional abuse with other disorders.Image:Image 2:ConclusionsThese fndings highlight the importance of preventing early traumatic events and providing trauma-informed care in early intervention and psychiatric services.Disclosure of InterestNone Declared
Methyl salicylate, an herbivore-induced plant volatile, has been shown to attract natural enemies and affect herbivore behavior. In this study, methyl salicylate was examined for its attractiveness ...to natural enemies of the soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), and for its direct effects on soybean aphid population growth rates. Methyl salicylate lures were deployed in plots within organic soybean Glycine max (L.) Merr. fields. Sticky card traps adjacent to and 1.5 m from the lure measured the relative abundance of natural enemies, and soybean aphid populations were monitored within treated and untreated plots. In addition, exclusion cage studies were conducted to determine methyl salicylate's effect on soybean aphid population growth rates in the absence of natural enemies. Significantly greater numbers of syrphid flies (Diptera: Syrphidae) and green lacewings (Neuroptera: Chrysopidae) were caught on traps adjacent to the methyl salicylate lure, but no differences in abundance were found at traps 1.5 m from the lure. Furthermore, abundance of soybean aphids was significantly lower in methyl salicylate-treated plots. In exclusion cage studies, soybean aphid numbers were significantly reduced on treated soybean plants when all plants were open to natural enemies. When plants were caged, however, soybean aphid numbers and population growth rates did not differ between treated and untreated plants suggesting no effect of methyl salicylate on soybean aphid reproduction and implicating the role of natural enemies in depressing aphid populations. Although aphid populations were reduced locally around methyl salicylate lures, larger scale studies are needed to assess the technology at the whole-field scale.
The resilience of the Etherington–Hubble relation Renzi, Fabrizio; Hogg, Natalie B; Giarè, William
Monthly notices of the Royal Astronomical Society,
05/2022, Letnik:
513, Številka:
3
Journal Article
Recenzirano
Odprti dostop
ABSTRACT
The Etherington reciprocity theorem, or distance duality relation (DDR), relates the mutual scaling of cosmic distances in any metric theory of gravity where photons are massless and ...propagate on null geodesics. In this paper, we make use of the DDR to build a consistency check based on its degeneracy with the Hubble constant, H0. We parametrize the DDR using the form η(z) = 1 + ϵz, thus only allowing small deviations from its standard value. We use a combination of late-time observational data to provide the first joint constraints on the Hubble parameter and ϵ with percentage accuracy: H0 = 68.6 ± 2.5 km s−1 Mpc−1 and $\epsilon = 0.001^{+0.023}_{-0.026}$. We build our consistency check using these constraints and compare them with the results obtained in extended cosmological models using cosmic microwave background data. We find that extensions to Λ cold dark matter (ΛCDM) involving massive neutrinos and/or additional dark radiation are in perfect agreement with the DDR, while models with non-zero spatial curvature show a preference for DDR violation, i.e. ϵ ≠ 0 at the level of ∼1.5σ. Most importantly, we find a mild 2σ discrepancy between the validity of the DDR and the latest publicly available Cepheid-calibrated Type Ia supernova (SNIa) constraint on H0. We discuss the potential consequences of this for both the Etherington reciprocity theorem and the H0 tension.
Shan–Chen interacting vacuum cosmology Hogg, Natalie B; Bruni, Marco
Monthly notices of the Royal Astronomical Society,
02/2022, Letnik:
511, Številka:
3
Journal Article
Recenzirano
Odprti dostop
ABSTRACT
In this paper, we introduce a novel class of interacting vacuum models, based on recasting the equation of state originally developed in the context of lattice kinetic theory by Shan & Chen ...as the coupling between the vacuum and cold dark matter (CDM). This coupling allows the vacuum to evolve and is non-linear around a characteristic energy scale ρ*, changing into a linear coupling with a typical power-law evolution at scales much lower and much higher than ρ*. Focusing on the simplest sub-class of models where the interaction consists only of an energy exchange and the CDM remains geodesic, we first illustrate the various possible models that can arise from the Shan–Chen coupling, with several different behaviours at both early and late times depending on the values of the model parameters selected. We then place the first observational constraints on this Shan–Chen interacting vacuum scenario, performing an MCMC analysis to find those values of the model and cosmological parameters which are favoured by observational data. We focus on models where the non-linearity of the coupling is relevant at late times, choosing for the reference energy scale ρ*, the critical energy density in ΛCDM. We show that the observational data we use are compatible with a wide range of models which result in different cosmologies. However, we also show that ΛCDM is preferred over all of the Shan–Chen interacting vacuum models that we study, and comment on the inability of these models to relax the H0 and σ8 tensions.
PDF
