Microbial environment shapes immune function and cloacal microbiota dynamics in zebra finches <i>Taeniopygia guttata</i>

BACKGROUND: The relevance of the host microbiota to host ecology and evolution is well acknowledged. However, the effect of the microbial environment on host immune function and host microbiota dynamics is understudied in terrestrial vertebrates. Using a novel experimental approach centered on the manipulation of the microbial environment of zebra finches Taeniopygia guttata, we carried out a study to investigate effects of the host's microbial environment on: 1) constitutive immune function, 2) the resilience of the host cloacal microbiota; and 3) the degree to which immune function and host microbiota covary in microbial environments that differ in diversity. RESULTS: We explored immune indices (hemagglutination, hemolysis, IgY levels and haptoglobin concentration) and host-associated microbiota (diversity and composition) in birds exposed to two experimental microbial environments differing in microbial diversity. According to our expectations, exposure to experimental microbial environments led to differences related to specific antibodies: IgY levels were elevated in the high diversity treatment, whereas we found no effects for the other immune indices. Furthermore, according to predictions, we found significantly increased richness of dominant OTUs for cloacal microbiota of birds of the high diversity compared with the low diversity group. In addition, cloacal microbiota of individual females approached their baseline state sooner in the low diversity environment than females in the high diversity environment. This result supported a direct phenotypically plastic response of host microbiota, and suggests that its resilience depends on environmental microbial diversity. Finally, immune indices and cloacal microbiota composition tend to covary within treatment groups, while at the same time, individuals exhibited consistent differences of immune indices and microbiota characteristics. CONCLUSION: We show that microbes in the surroundings of terrestrial vertebrates can influence immune function and host-associated microbiota dynamics over relatively short time scales. We suggest that covariation between immune indices and cloacal microbiota, in addition to large and consistent differences among individuals, provides potential for evolutionary adaptation. Ultimately, our study highlights that linking environmental and host microbiotas may help unravelling immunological variation within and potentially among species, and together these efforts will advance the integration of microbial ecology and ecological immunology

Gender (in)equality at the kitchen table: A diary study on how parents’ coordination facilitates an equal task division and relationship quality

Although women's labour force participation has increased, women still lag behind in financial independence and men in spending time on parenting. Insight in individuals' explicit conversations with their partner about how to coordinate daily household, childcare and paid work may help to overcome these persistent inequalities. Using a daily diary design, the present study examined to what extent daily conversations with the partner about household, childcare and paid work can boost a more equal, fair task division and relationship quality among Dutch mothers and fathers in a heterosexual relationship (N = 1235 daily reported conversations nested in 157 participants; 66.2% female). Mixed model results showed that (1) on days when participants conversed more with their partner about household tasks, they reported a more egalitarian task division and higher satisfaction with and fairness of the task division, and higher relationship quality (2) this higher daily satisfaction with and perceived fairness of the task division (but not egalitarianism) were, in turn, associated with higher relationship quality and (3) conversations had limited spill-over effects to the next day, stressing the importance of daily coordination. Together, these findings imply that daily household coordination helps parents to overcome traditional gender roles and align with their desired work/family division

The microbial environment modulates non-genetic maternal effects on egg immunity

BACKGROUND: In a diverse microbial world immune function of animals is essential. Diverse microbial environments may contribute to extensive variation in immunological phenotypes of vertebrates, among and within species and individuals. As maternal effects benefit offspring development and survival, whether females use cues about their microbial environment to prime offspring immune function is unclear. To provide microbial environmental context to maternal effects, we asked if the bacterial diversity of the living environment of female zebra finches Taeniopygia guttata shapes maternal effects on egg immune function. We manipulated environmental bacterial diversity of birds and tested if females increased immunological investment in eggs in an environment with high bacterial diversity (untreated soil) versus low (gamma-sterilized soil). We quantified lysozyme and ovotransferrin in egg albumen and IgY in egg yolk and in female blood, and we used 16S rRNA gene sequencing to profile maternal cloacal and eggshell microbiotas. RESULTS: We found a maternal effect on egg IgY concentration that reflected environmental microbial diversity: females who experienced high diversity deposited more IgY in their eggs, but only if maternal plasma IgY levels were relatively high. We found no effects on lysozyme and ovotransferrin concentrations in albumen. Moreover, we uncovered that variation in egg immune traits could be significantly attributed to differences among females: for IgY concentration in yolk repeatability R = 0.80; for lysozyme concentration in albumen R = 0.27. Furthermore, a partial least squares path model (PLS-PM) linking immune parameters of females and eggs, which included maternal and eggshell microbiota structures and female body condition, recapitulated the treatment-dependent yolk IgY response. The PLS-PM additionally suggested that the microbiota and physical condition of females contributed to shaping maternal effects on egg immune function, and that (non-specific) innate egg immunity was prioritized in the environment with low bacterial diversity. CONCLUSIONS: The microbial environment of birds can shape maternal effects on egg immune function. Since immunological priming of eggs benefits offspring, we highlight that non-genetic maternal effects on yolk IgY levels based on cues from the parental microbial environment may prove important for offspring to thrive in the microbial environment that they are expected to face

Three-dimensional quantification of soft tissue changes and its relationship to skeletal changes after Le Fort III, monobloc, and facial bipartition in syndromic craniosynostosis

To determine the effect of midface surgery on soft tissue changes and their relationship to hard tissue changes in patients with syndromic craniosynostosis. A retrospective analysis of patients who had undergone Le Fort III (LFIII), monobloc (MB), or facial bipartition (FB) was conducted. A 3D soft tissue mesh was generated from the preoperative scan and registered to the postoperative scan, after which the advancement was visualised. A total of 68 patients were included: 28 had undergone LFIII, 27 MB, and 13 FB. The included diagnoses were Apert (n = 23), Crouzon (n = 34), and craniofrontonasal syndrome (n = 11). After LFIII, most soft tissue advancement was seen around subnasale and pronasale (mean 15.1 ± 5.9 mm and 14.7 ± 5.7 mm, at age 7–12 years). After MB, a greater hard tissue than soft tissue advancement was seen for most landmarks, showing a high positive correlation. In patients undergoing FB without distraction (n = 10), mean preoperative inter-canthal distance was 48.9 mm, this reduced by 6.9 mm postoperatively. This study provides a comprehensive overview of the outcomes after midface surgery using 3D quantification for a better understanding of the soft tissue changes and their relationship to hard tissue changes.</p

Mineral reaction kinetics constrain the length scale of rock matrix diffusion

Mass transport by aqueous fluids is a dynamic process in shallow crustal systems, redistributing nutrients as well as contaminants. Rock matrix diffusion into fractures (void space) within crystalline rock has been postulated to play an important role in the transient storage of solutes. The reacted volume of host rock involved, however, will be controlled by fluid-rock reactions. Here we present the results of a study which focusses on defining the length scale over which rock matrix diffusion operates within crystalline rock over timescales that are relevant to safety assessment of radioactive and other long-lived wastes. Through detailed chemical and structural analysis of natural specimens sampled at depth from an active system (Toki Granite, Japan), we show that, contrary to commonly proposed models, the length scale of rock matrix diffusion may be extremely small, on the order of centimetres, even over timescales of millions of years. This implies that in many cases the importance of rock matrix diffusion will be minimal. Additional analyses of a contrasting crystalline rock system (Carnmenellis Granite, UK) corroborate these results

The hydrodynamics of the supernova remnant Cas A: The influence of the progenitor evolution on the velocity structure and clumping

There are large differences in the proposed progenitor models for the Cas A SNR. One of these differences is the presence or absence of a Wolf-Rayet (WR) phase of the progenitor star. The mass loss history of the progenitor star strongly affects the shape of the Supernova remnant (SNR). In this paper we investigate whether the progenitor star of Cas A had a WR phase or not and how long it may have lasted. We performed two-dimensional multi-species hydrodynamical simulations of the CSM around the progenitor star for several WR life times, each followed by the interaction of the supernova ejecta with the CSM. We then looked at the influence of the length of the WR phase and compared the results of the simulations with the observations of Cas A. The difference in the structure of the CSM, for models with different WR life times, has a strong impact on the resulting SNR. With an increasing WR life time the reverse shock velocity of the SNR decreases and the range of observed velocities in the shocked material increases. Furthermore, if a WR phase occurs, the remainders of the WR shell will be visible in the resulting SNR. Comparing our results with the observations suggests that the progenitor star of Cas A did not have a WR phase. We also find that the quasi-stationary flocculi (QSF) in Cas A are not consistent with the clumps from a WR shell that have been shocked and accelerated by the interaction with the SN ejecta. We can also conclude that for a SN explosion taking place in a CSM that is shaped by the wind during a short < 15000 yr WR phase, the clumps from the WR shell will be visible inside the SNR.Comment: 11 figures, 11 pages, accepted for publication in A&

Declared non-essential during the COVID-19 pandemic: Effects on professional identity

This study applies a social identity lens to show that, during the COVID-19 pandemic, the Dutch government’s classification of occupations and labor market sectors as essential versus non-essential imposed a professional identity threat to those categorized as non-essential. Specifically, we hypothesized (1) that non-essential workers in the Netherlands would report lower professional identification (PI) during the pandemic relative to essential workers; (2) that non-essential workers’ mandatory shift to working from home and working fewer hours would (partially) explain their lower PI relative to essential workers; (3) that gender differences would emerge in the impact of categorization as (non-)essential worker on PI levels; and (4) that lower PI would negatively relate to work productivity and performance during the pandemic. Empirical evidence based on three cross-sectional datasets sampled among the Dutch working population during two peak waves of COVID-19 infections and national lockdowns (May/June 2020; Study 1: N = 371; November/December 2020, Study 2: N = 467; Study 3 = 735) all confirmed that non-essential workers reported lower PI relative to essential workers. The explanation for this outcome varied at different stages in the pandemic. Study 1 results showed that lower PI among those declared non-essential was partially explained by non-essential workers’ work location (home-bound) and reduced work hours, but only during the 1st peak wave. As the pandemic continued (2nd peak wave; Study 2 and 3), gender differences emerged, with more negative consequences of being classified non-essential for women than men. Non-essential workers’ lower PI levels were also associated with lower work productivity and performance. These findings underscore the importance of understanding social identity processes during the pandemic. We discuss socio-psychological ramifications of government regulations to control health crises, given how these may inadvertently undermine the professional identity of over half a working population in society