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Seed lots of tomato and capsicum (Solanum lycopersicon and Capsicum annuum, respectively) are required to be free of quarantine pests before their entry to Australia is permitted. Testing of samples from 118 larger seed lots in the period 2019–2021 revealed that 31 (26.3%) carried one or more of four Tobamovirus species, including tomato mottle mosaic virus (ToMMV), which is a quarantine pest for Australia. Testing of samples from a further 659 smaller seed lots showed that 123 (18.7%) carried a total of five Tobamovirus species, including ToMMV and tomato brown rugose fruit virus (ToBRFV), which is also a quarantine pest for Australia. Estimated prevalence of contamination by tobamoviruses ranged from 0.388% to 0.004% in contaminated larger seed lots. Analyses of these data allow us to estimate probabilities of detection of contamination under different regulatory settings.

An antigenic 30 K virion protein of Heliothis armigera entomopoxvirus (HaEPV) has been identified as a homologue of the chordopoxvirus (ChPV) VP8 major virion core protein. Like its homologue in vaccinia virus, the mature HaEPV 30 K protein is derived by post-translational cleavage of a precursor at a conserved AGA motif. The HaEPV 30 K protein is the first EPV structural virion protein to be described, and elucidation of its characteristics provides evidence for the assumption that morphological similarities observed between virions of the sub-families Entomopoxvirinae and Chordopoxvirinae by microscopy reflect corresponding similarities at a molecular level. Sequencing of the HaEPV genome adjacent to the 30K locus identified an ORF encoding a homologue of the regulatory sub-unit of the ChPV poly(A) polymerase enzyme; the conceptual product of this ORF showed 25-31% aa sequence identity to those of various ChPVs. The presence of this gene in the HaEPV genome supports the hypothesis that there is a substantial correspondence in basic metabolic processes of members of the two poxvirus sub-families, despite their utilization of divergent host groups. In contrast, the relative positions of the 30 K and poly(A) polymerase loci in the HaEPV genome provide further evidence of substantial genomic re-arrangement subsequent to divergence of these viral taxa.

Continuously replicating cell lines have been established from embryonic tissue and circulating hemolymph cells of the melolonthine Antitrogus parvulus Britton. Isozyme analyses demonstrated that cell lines from both tissue sources expressed essentially the same isoforms of enzymes as A. parvulus larvae and thus confirmed the species of their origin. Karyotype analyses showed that cells from both tissue sources had accumulated changes in chromosome number and morphology during culture. Availability of melolonthine-derived cells should assist in vitro studies of the pathogens of this important group of beetles.

Background Regular physical activity is the prime modality for the prevention of numerous non-communicable diseases and has also been advocated for resilience against COVID-19 and other infectious diseases. However, there is currently no systematic and quantitative evidence synthesis of the association between physical activity and the strength of the immune system. Objective To examine the association between habitual physical activity and (1) the risk of community-acquired infectious disease, (2) laboratory‐assessed immune parameters, and (3) immune response to vaccination. Methods We conducted a systemic review and meta-analysis according to PRISMA guidelines. We searched seven databases (MEDLINE, Embase, Cochrane CENTRAL, Web of Science, CINAHL, PsycINFO, and SportDiscus) up to April 2020 for randomised controlled trials and prospective observational studies were included if they compared groups of adults with different levels of physical activity and reported immune system cell count, the concentration of antibody, risk of clinically diagnosed infections, risk of hospitalisation and mortality due to infectious disease. Studies involving elite athletes were excluded. The quality of the selected studies was critically examined following the Cochrane guidelines using ROB2 and ROBINS_E. Data were pooled using an inverse variance random-effects model. Results Higher level of habitual physical activity is associated with a 31% risk reduction (hazard ratio 0.69, 95% CI 0.61–0.78, 6 studies, N  = 557,487 individuals) of community-acquired infectious disease and 37% risk reduction (hazard ratio 0.64, 95% CI 0.59–0.70, 4 studies, N  = 422,813 individuals) of infectious disease mortality. Physical activity interventions resulted in increased CD4 cell counts (32 cells/µL, 95% CI 7–56 cells/µL, 24 studies, N  = 1112 individuals) and salivary immunoglobulin IgA concentration (standardised mean difference 0.756, 95% CI 0.146–1.365, 7 studies, N  = 435 individuals) and decreased neutrophil counts (704 cells/µL, 95% CI 68–1340, 6 studies, N  = 704 individuals) compared to controls. Antibody concentration after vaccination is higher with an adjunct physical activity programme (standardised mean difference 0.142, 95% CI 0.021–0.262, 6 studies, N  = 497 individuals). Conclusion Regular, moderate to vigorous physical activity is associated with reduced risk of community-acquired infectious diseases and infectious disease mortality, enhances the first line of defence of the immune system, and increases the potency of vaccination. Protocol registration The original protocol was prospectively registered with PROSPERO (CRD42020178825).

Human societies, and their well-being, depend to a significant extent on the state of the ecosystems that surround them. These ecosystems are changing rapidly usually in response to anthropogenic changes in the environment. To determine the likely impact of environmental change on ecosystems and the best ways to manage them, it would be desirable to be able to predict their future states. We present a proposal to develop the paradigm of predictive systems ecology, explicitly to understand and predict the properties and behaviour of ecological systems. We discuss the necessary and desirable features of predictive systems ecology models. There are places where predictive systems ecology is already being practised and we summarize a range of terrestrial and marine examples. Significant challenges remain but we suggest that ecology would benefit both as a scientific discipline and increase its impact in society if it were to embrace the need to become more predictive.

Winning or losing contests can impact subsequent competitive behaviour and the duration of these effects can be prolonged. While it is clear effects depend on social and developmental environments, the extent to which they are heritable, and hence evolvable, is less clear and remains untested. Furthermore, theory predicts that winner and loser effects should evolve independently of actual fighting ability, but again tests of this prediction are limited. Here we used artificial selection on replicated beetle populations to show that the duration of loser effects can evolve, with a realized heritability of about 17%. We also find that naive fighting ability does not co-evolve with reductions in the duration of the loser effect. We discuss the implications of these findings and how they corroborate theoretical predictions.

Brilliantly-colored birds are a model system for research into evolution and sexual selection. Red, orange, and yellow carotenoid-colored plumages have been considered honest signals of condition; however, sex differences in feather pigments and microstructures are not well understood. Here, we show that microstructures, rather than carotenoid pigments, seem to be a major driver of male–female color differences in the social, sexually-dimorphic tanager genus Ramphocelus . We comprehensively quantified feather (i) color (using spectrophotometry), (ii) pigments (using liquid chromatography–mass spectrometry (LC–MS)), and (iii) microstructures (using scanning electron microscopy (SEM) and finite-difference time-domain (FDTD) optical modeling). Males have significantly more saturated color patches than females. However, our exploratory analysis of pigments suggested that males and females have concordant carotenoid pigment profiles across all species (MCMCglmm model, female:male ratio = 0.95). Male, but not female, feathers have elaborate microstructures which amplify color appearance. Oblong, expanded feather barbs in males enhance color saturation (for the same amount of pigment) by increasing the transmission of optical power through the feather. Dihedral barbules (vertically-angled, strap-shaped barbules) in males reduce total reflectance to generate “super black” and “velvet red” plumage. Melanin in females explains some, but not all, of the male–female plumage differences. Our results suggest that a widely cited index of honesty, carotenoid pigments, cannot fully explain male appearance. We propose that males are selected to evolve amplifiers—in this case, microstructures that enhance appearance—that are not necessarily themselves linked to quality.

Natural selection and the evolution of eusociality Eusocial insects, including ants and many wasp and bee species, form hierarchical communities comprising reproductive queens and sterile workers. This means that some individuals sacrifice their own reproductive potential in order to raise the offspring of others, a fact that Darwin recognized as a challenge to evolutionary theory. The most widely accepted explanations for the phenomenon rely on kin selection theory based on inclusive fitness — individual fitness derived by increasing the survival of a relatives' offspring. In an Analysis feature, Martin Nowak, Corina Tarnita and Edward O. Wilson point out that this approach has its limitations. They demonstrate mathematically that inclusive fitness is a viable alternative to the direct fitness of standard natural selection only for a well-defined subset of situations — it is not generally applicable. A simpler explanation is provided by standard natural selection theory in the context of precise models of population structure. Eusociality, in which some individuals reduce their own lifetime reproductive potential to raise the offspring of others, underlies the most advanced forms of social organization and the ecologically dominant role of social insects and humans. For the past four decades kin selection theory, based on the concept of inclusive fitness, has been the major theoretical attempt to explain the evolution of eusociality. Here we show the limitations of this approach. We argue that standard natural selection theory in the context of precise models of population structure represents a simpler and superior approach, allows the evaluation of multiple competing hypotheses, and provides an exact framework for interpreting empirical observations.

BackgroundExercise improves physical capacity in patients with end-stage renal disease on haemodialysis (HD), but few patients engage in it. Whole-body vibration exercise (WBVE) is a novel protocol that has been shown to benefit frail elderly patients’ rehabilitation. We assessed the utility of WBVE before HD sessions and tested methods to inform the design of a randomized controlled trial (RCT).MethodsPhysical condition and quality of life were assessed at enrolment and repeated 2 weeks later in a pilot study of 49 patients undergoing regular HD. All patients then undertook 8 weeks of WBVE, thrice weekly for 3 min, after which the assessments were repeated and results compared (paired t-tests). Further assessments were made after a 4-week layoff. Patients completed a post-study questionnaire about their experiences of using WBVE. The reproducibility of WBVE and effects on measures of functionality, muscle strength, indirect exercise capacity, nutritional status, bone health and quality of life were recorded to undertake a power calculation for an RCT.ResultsOf 49 patients enrolled, 25 completed all assessments. The dropout rate was high at 49%, but overall, WBVE was an acceptable form of exercise. Functionality as assessed by the 60-s sit-to-stand test (STS-60) improved significantly by 11% (P = 0.002). Some quality of life domains also improved significantly. All improvements were maintained 4 weeks after discontinuing WBVE.ConclusionsWBVE was acceptable, safe, easily incorporated into the routine of HD and was associated with useful improvements in physical function sufficient to justify a RCT.