A simplification of the traditional statistical model in the presence of symmetry
In: Statistische Hefte: internationale Zeitschrift für Theorie und Praxis = Statistical papers, Band 22, Heft 3, S. 195-206
ISSN: 1613-9798
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In: Statistische Hefte: internationale Zeitschrift für Theorie und Praxis = Statistical papers, Band 22, Heft 3, S. 195-206
ISSN: 1613-9798
In: Statistische Hefte: internationale Zeitschrift für Theorie und Praxis = Statistical papers, Band 21, Heft 4, S. 296-304
ISSN: 1613-9798
In: Statistische Hefte: internationale Zeitschrift für Theorie und Praxis = Statistical papers, Band 20, Heft 3, S. 148-159
ISSN: 1613-9798
In: European journal of international relations, Band 29, Heft 4, S. 903-928
ISSN: 1460-3713
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.
In: PNAS nexus, Band 3, Heft 9
ISSN: 2752-6542
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.
In: Statistische Hefte: internationale Zeitschrift für Theorie und Praxis = Statistical papers, Band 22, Heft 3, S. 231-233
ISSN: 1613-9798
In: Cultural Memory in the Present
In: Cultural Memory in the Present Ser.
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
In: PNAS nexus, Band 3, Heft 8
ISSN: 2752-6542
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.
In: PNAS nexus, Band 1, Heft 1
ISSN: 2752-6542
In: Statistische Hefte: internationale Zeitschrift für Theorie und Praxis = Statistical papers, Band 23, Heft 2, S. 134-141
ISSN: 1613-9798
In: PNAS nexus, Band 3, Heft 3
ISSN: 2752-6542
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.
In: PNAS nexus, Band 1, Heft 5
ISSN: 2752-6542
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.
In: PNAS nexus, Band 2, Heft 12
ISSN: 2752-6542
Abstract
Given historical inequities in cannabis laws and policies, there is an obligation on the part of researchers and policy makers to actively work toward improving equity in cannabis research at a time when the field is rapidly expanding. We wish to propose a way forward for cannabis research that acknowledges this history of discrimination and misuse of institutional power and embraces equity and inclusion. This article provides a brief perspective on historical drug policy, recent legalization trends that have disproportionately benefitted some groups over others, and the repercussions of those trends for the cannabis research enterprise. In addition, it proposes five key actions in both policy and research domains that are necessary to move the field of cannabis research, and perhaps biomedical research in substance use more broadly, forward in a productive and inclusionary way. Specifically, recommendations focus on equity-focused legislation and policy, supporting the entry and retention of scientists of color into the field, engaging in more ethical research practices, and practicing intentionally inclusive recruitment of participants will help to move the field of cannabis research forward. These efforts will ensure that scientific gains are shared equitably moving forward.
In: PNAS nexus, Band 1, Heft 5
ISSN: 2752-6542
Abstract
The death of King Charles XII of Sweden has remained as a mystery for more than three centuries. Was he assassinated by his own men or killed by the enemy fire? Charles was killed by a projectile perforating his skull from left to right. In this study, we utilized a Synbone ballistic skull phantom and modern radiological imaging to clarify the factors behind the observed head injuries. We examined whether a musket ball fired from the enemy lines would be the most potential projectile. Our experiments with a leaden 19.5 mm musket ball demonstrated that at velocities of 200 to 250 m/s, it could cause similar type of injuries as observed in the remains of Charles . The radiological imaging supported the theory that the projectile was not a leaden but of some harder metal, as we could detect remnants of lead inside the wound channel unlike in Charles' case. In addition, our experiments showed that a 19.5mm musket ball produces max. 17mm hole into a felt material . The main evidence supporting 19.5 mm projectile size has been a 19-19.5mm bullet hole in a hat that Charles was wearing during his death. Additional experiments with a 25.4 mm steel ball produced approximately 20 mm hole in the felt. As our musket ball experiments also resulted in considerably smaller cranial injuries than those in Charles' case, we can conclude that the deadly projectile wasn't leaden and was more than 19.5 mm in diameter, potentially an iron cartouche ball that was shot from the enemy lines.
In: PNAS nexus, Band 2, Heft 7
ISSN: 2752-6542
Abstract
The South Shetland Trough, Antarctica, is an underexplored region for microbiological and biotechnological exploitation. Herein, we describe the isolation and characterization of the novel bacterium Lacinutrix shetlandiensis sp. nov. WUR7 from a deep-sea environment. We explored its chemical diversity via a metabologenomics approach, wherein the OSMAC strategy was strategically employed to upregulate cryptic genes for secondary metabolite production. Based on hybrid de novo whole genome sequencing and digital DNA–DNA hybridization, isolate WUR7 was identified as a novel species from the Gram-negative genus Lacinutrix. Its genome was mined for the presence of biosynthetic gene clusters with limited results. However, extensive investigation of its metabolism uncovered an unusual tryptophan decarboxylase with high sequence homology and conserved structure of the active site as compared to ZP_02040762, a highly specific tryptophan decarboxylase from Ruminococcus gnavus. Therefore, WUR7's metabolism was directed toward indole-based alkaloid biosynthesis by feeding it with L-tryptophan. As expected, its metabolome profile changed dramatically, by triggering the extracellular accumulation of a massive array of metabolites unexpressed in the absence of tryptophan. Untargeted LC-MS/MS coupled with molecular networking, followed along with chemoinformatic dereplication, allowed for the annotation of 10 indole alkaloids, belonging to β-carboline, bisindole, and monoindole classes, alongside several unknown alkaloids. These findings guided us to the isolation of a new natural bisindole alkaloid 8,9-dihydrocoscinamide B (1), as the first alkaloid from the genus Lacinutrix, whose structure was elucidated on the basis of extensive 1D and 2D NMR and HR-ESIMS experiments. This comprehensive strategy allowed us to unlock the previously unexploited metabolome of L. shetlandiensis sp. nov. WUR7.