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COVID-19 has exposed profound governance challenges that demand more diverse and creative approaches to global health governance moving forward. This article works towards such a pluralization of the field by foregrounding the vital role played by heterodox actors during the pandemic. Heterodox global health actors are backgrounded actors who improve health in different parts of the world, but who remain politically marginalized – and epistemically invisibilized – because they depart in crucial respects from the liberal orthodoxy pervading the field of global health governance. The article analytically foregrounds those heterodox actors through an architectural inversion – a relational approach to the study of global health governance that builds upon recent methodological insights from postcolonial studies, infrastructure studies, and science and technology studies. The article then harnesses that methodological approach to empirically investigate the COVID-19 activities of three different heterodox actors: rebel groups providing public health in the borderlands of Myanmar, a women's vigilante movement stitching face masks in the Czech Republic, and a maverick scientific platform for the international sharing of viral sequence data. Performing that architectural inversion begins to loosen the dominance of the liberal episteme within the practice and study of global health governance. It further visibilizes how that field is continually co-produced by the background activities of many such heterodox actors. It also lays conceptual foundations for a more heterodox future research agenda on global health governance – and arguably global governance more broadly – in response to the numerous unresolved challenges revealed by COVID-19.

Abstract
The bacterial mannose phosphotransferase system (Man-PTS) mediates uptake of selected monosaccharides. Simultaneously, it is a receptor for diverse bacteriocins such as subclass IIa pediocin-like bacteriocins and some subclass IId ones (garvicins ABCQ, lactococcins ABZ, BacSJ, ubericin K, and angicin). So far, no attempt has been made to categorize this ever-expanding group of bacteriocins. Here, we identified Man-PTS as a receptor for a number of previously uncharacterized bacteriocins, and demonstrated that they all belong to a large family of Man-PTS-binding nonpediocin-like peptides, providing new insights into their structure and function. Based on amino acid sequence similarities between members of this family, we propose their classification into five groups. This classification conveniently distinguishes bacteriocins with specific structures and properties regarding their spectrum of antimicrobial activity and pattern of interaction with Man-PTS. With respect to the latter, we indicate individual amino acid residues or regions of Man-PTS and the bacteriocin responsible for their interaction. In Man-PTS, these residues localize to the exterior of the transport complex, specifically the extracellular loop of the so-called Vmotif domain-containing regions γ and/or γ+, and to the interior of the transport complex, specifically the interface between the Core and Vmotif domains. Finally, we propose that while the bacteriocins from separate groups display specific binding patterns to Man-PTS, the general mechanism of their interaction with the receptor is universal despite significant differences in their predicted structures, i.e. after initial docking on the bacterial cell through an interaction with the Man-PTS regions γ and/or γ+, they pull away its Core and Vmotif from one another to form a pore across the membrane.

Abstract
There is an accumulation of evidence that the human gut microbiota plays a role in maintaining health, and that an altered gut microbiota (sometimes called dysbiosis) associates with risk for many noncommunicable diseases. However, the dynamics of disease-linked bacteria in the gut and other body sites remain unclear. If microbiome alterations prove causative in particular diseases, therapeutic intervention may be possible. Furthermore, microbial signature taxa have been established for the diagnosis of some diseases like colon cancer. We identified 163 disease-enriched and 98 disease-depleted gut microbiome signature taxa at species-level resolution (signature species) from 10 meta-analyses of multiple diseases such as colorectal cancer, ulcerative colitis, Crohn's disease, irritable bowel syndrome, pancreatic cancer, and COVID-19 infection. Eight signature species were enriched and nine were depleted across at least half of the diseases studied. Compared with signature species depleted in diseases, a significantly higher proportion of disease-enriched signature species were identified as extra-intestinal (primarily oral) inhabitants, had been reported in bacteremia cases from the literature, and were aerotolerant anaerobes. These findings highlight the potential involvement of oral microbes, bacteremia isolates, and aerotolerant anaerobes in disease-associated gut microbiome alterations, and they have implications for patient care and disease management.

A Systems Theory of Religion, still unfinished at Niklas Luhmann's death in 1998, was first published in German two years later thanks to the editorial work of André Kieserling. One of Luhmann's most important projects, it exemplifies his later work while redefining the subject matter of the sociology of religion. Religion, for Luhmann, is one of the many functionally differentiated social systems that make up modern society. All such subsystems consist entirely of communications and all are "autopoietic," which is to say, self-organizing and self-generating. Here, Luhmann explains how religi

Abstract
Assisted reproductive technologies (ART) are commonly used to address human infertility and to boost livestock production. During ART, procedures such as in vitro fertilization, artificial insemination, and intracytoplasmic sperm injection introduce gametes and embryos to unnatural and potentially stressful conditions that can influence offspring health, often via epigenetic effects. In this perspective we summarize these key risks of ART for embryonic and longer-term offspring fitness, emphasizing the need for experimental research on animal models to determine causal links between ART and offspring fitness across multiple generations. We also highlight how ART can bypass a range of naturally and sexually selected mechanisms that occur in the female reproductive tract and/or via female secretions that ultimately determine which sperm fertilize their eggs. We further argue that this curtailment of female-modulated mechanisms of sperm selection may have important consequences for ART-conceived offspring. We encourage the development of ART methods that better mimic natural processes of sperm selection and embrace the fundamental principles of natural and sexual selection. Ultimately, the aim of this perspective is to encourage dialogue between the fields of evolutionary biology and applied areas of animal and human reproduction.

Abstract
Glycoproteins are abundant within the human reproductive system and alterations in glycosylation lead to reproductive disorders, suggesting that glycans play an important role in reproductive function. In this study, we used the Drosophila reproductive system as a model to investigate the biological functions of O-glycosylation. We found that O-glycosylation in the male accessory glands, an organ responsible for secreting seminal fluid proteins, plays important roles in female postmating behavior. The loss of one O-glycosyltransferase, PGANT9, in the male reproductive system resulted in decreased egg production in mated females. We identified one substrate of PGANT9, lectin-46Ca (CG1656), which is known to affect female postmating responses. We further show that the loss of lectin-46Ca O-glycosylation affects its ability to associate with sperm tails, resulting in reduced transfer within the female reproductive system. Our results provide the first example that O-glycosylation of a seminal fluid protein affects its ability to associate with sperm in vivo. These studies may shed light on the biological function of O-glycans in mammalian reproduction.

Abstract
The Covid-19 pandemic revealed the difficulties of vaccinating a population under the circumstances marked by urgency and limited availability of doses while balancing benefits associated with distinct guidelines satisfying specific ethical criteria. We offer a vaccination strategy that may be useful in this regard. It relies on the mathematical concept of envy-freeness. We consider finding balance by allocating the resource among individuals that seem heterogeneous concerning the direct and indirect benefits of vaccination, depending on age. The proposed strategy adapts a constructive approach in the literature based on Sperner's Lemma to point out an approximate division of doses guaranteeing that both benefits are optimized each time a batch becomes available. Applications using data about population age distributions from diverse countries suggest that, among other features, this strategy maintains the desired balance, throughout the entire vaccination period. We discuss complementary aspects of the method in the context of epidemiological models of age-stratified Susceptible - Infected - Recovered (SIR) type.

Abstract
Creative problem solving is a fundamental skill of human cognition and is conceived as a search process whereby a novel and appropriate solution is generated. However, it is unclear whether children are able to balance novelty and appropriateness to generate creative solutions and what are the underlying computational mechanisms. Here, we asked children, ranging from 10 to 11 years old, to perform a word association task according to three instructions, which triggered a more appropriate (ordinary), novel (random), or balanced (creative) response. Results revealed that children exhibited greater cognitive flexibility in the creative condition compared to the control conditions, as revealed by the structure and resiliency of the semantic networks. Moreover, responses' word embeddings extracted from pretrained deep neural networks showed that semantic distance and category switching index increased in the creative condition with respect to the ordinary condition and decreased compared to the random condition. Critically, we showed how children efficiently solved the exploration/exploitation trade-off to generate creative associations by fitting a computational reinforcement learning (RL) model that simulates semantic search strategies. Our findings provide compelling evidence that children balance novelty and appropriateness to generate creative associations by optimally regulating the level of exploration in the semantic search. This corroborates previous findings on the adult population and highlights the crucial contribution of both components to the overall creative process. In conclusion, these results shed light on the connections between theoretical concepts such as bottom-up/top-down modes of thinking in creativity research and the exploration/exploitation trade-off in human RL research.