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Abstract The human gut virome, which is mainly composed of bacteriophages, also includes viruses infecting archaea, yet their role remains poorly understood due to lack of isolates. Here, we characterize a temperate archaeal virus (MSTV1) infecting Methanobrevibacter smithii, the dominant methanogenic archaeon of the human gut. The MSTV1 genome is integrated in the host chromosome as a provirus which is sporadically induced, resulting in virion release. Using cryo-electron tomography, we capture several intracellular virion assembly intermediates and confirm that only a small fraction of the host population actively produces virions in vitro. Similar low frequency of induction is observed in a mouse colonization model, using mice harboring a stable consortium of 12 bacterial species (OMM12). Transcriptomic analysis suggests a regulatory lysogeny-lysis switch involving an interplay between viral proteins to maintain virus-host equilibrium, ensuring host survival and viral persistence. Thus, our study sheds light on archaeal virus-host interactions and highlights similarities with bacteriophages in establishing stable coexistence with their hosts in the gut.

La meliponicultura es un legado presente en la vida rural en Nicaragua que se encuentra en riesgo de desaparecer por la pérdida de diversidad biocultural. Ésta sostiene vínculos socioecológicos indispensables para la agricultura campesina y la reproducción de la vida. El objetivo de este estudio es analizar el estado de la meliponicultura en Nicaragua, su crecimiento, actores, procesos y aspectos sociales, ecológicos y productivos. Se centra en una investigación acción participativa y el uso de herramientas cuali-cuantitativas. Meliponicultores organizados de todo el país se juntaron para compartir ubicación, motivaciones, saberes, y los desafíos de la actividad. Hay un estimado de 11 963 meliponicultores, que conocen al menos 34 especies de abejas nativas sin aguijón de las cuales crían 22 especies. Estos practican diferentes meliponiculturas: tradicionales (80 %), conservacionistas (11 %) y resignificadas (9 %); cada una involucra diferentes motivaciones, prácticas productivas, procesos socio- ecológicos, pero mantienen como elemento común el arraigo cultural y los saberes contemporáneos. Se encontró que desde el 2008 existe una revitalización y un crecimiento de las meliponiculturas contemporáneas producido por la ejecución de al menos 16 proyectos regionales ejecutados por el estado, las organizaciones campesinas, la academia y aliados externos. Un aspecto clave ha sido el liderazgo de personas que retoman la meliponicultura como un pilar de sus procesos agroecológicos e identidad cultural. Las zonas de mayor crecimiento de las meliponiculturas coinciden con las regiones históricas de pueblos indígenas y de procesos agroecológicos sólidos. Hay dos visiones en diálogo y conflicto: el abejero centrado en la salud de las colmenas y otra centrada en la miel, no obstante, entre actores hay diálogo para resolver los desafíos ambientales, socio culturales, comerciales y de innovación.

We report the detailed background for the discovery and development of the synthesis of homopropargylic azides by the azido-alkynylation of alkenes. Initially, a strategy involving SOMOphilic alkynes was adopted, but only resulted in a 29% yield of the desired product. By switching to a radical-polar crossover approach and after optimization, a high yield (72%) of the homopropargylic azide was reached. Full insights are given about the factors that were essential for the success of the optimization process.

Abstract Background Chemically induced skin sensitization, or allergic contact dermatitis, is a common occupational and public health issue. Regulatory authorities require an assessment of potential to cause skin sensitization for many chemical products. Defined approaches for skin sensitization (DASS) identify potential chemical skin sensitizers by integrating data from multiple non-animal tests based on human cells, molecular targets, and computational model predictions using standardized data interpretation procedures. While several DASS are internationally accepted by regulatory agencies, the data interpretation procedures vary in logical complexity, and manual application can be time-consuming or prone to error. Results We developed the DASS App, an open-source web application, to facilitate user application of three regulatory testing strategies for skin sensitization assessment: the Two-out-of-Three (2o3), the Integrated Testing Strategy (ITS), and the Key Event 3/1 Sequential Testing Strategy (KE 3/1 STS) without the need for software downloads or computational expertise. The application supports upload and analysis of user-provided data, includes steps to identify inconsistencies and formatting issues, and provides predictions in a downloadable format. Conclusion This open-access web-based implementation of internationally harmonized regulatory guidelines for an important public health endpoint is designed to support broad user uptake and consistent, reproducible application. The DASS App is freely accessible via https://ntp.niehs.nih.gov/go/952311 and all scripts are available on GitHub ( https://github.com/NIEHS/DASS ).

Sections of a Happy Moment montre une famille asiatique jouant au ballon au pied de barres d’immeubles ; dans The Algiers’ Sections of a Happy Moment, des hommes donnent du pain à des mouettes en vol depuis un toit-terrasse de la Casbah d’Alger. Ces vidéos consistent en une longue succession d’images fixes issues d’un même processus de travail : des prises de vue des espaces sont combinées à des représentations des personnes réalisées en studio de manière à donner l’impression qu’un seul et même instant de la scène a été photographié selon une multitude de points de vue et de cadrages. Les deux vidéos consistent en un lent et long défilement bouclé de ces images composites en noir et blanc. L’effet conjoint de mouvement et d’immobilité est accusé par une bande-son qui égraine quelques notes de piano ou de guitare. Il s’agira de définir ce que recouvre l’expression « Sections of a Happy Moment ». On considérera que la représentation du bonheur dont il est question est tributaire des différents registres d’images auxquels ces œuvres se réfèrent, celui de la photographie de famille et celui des dispositifs de surveillance. Il conviendra également de prendre en compte le contexte architectural où ces scènes sont supposées avoir lieu ainsi que ceux et celles qui y vivent. C’est enfin de rythme des vidéos qui sera analysé en montrant qu’il permet d’établir une durée en phase avec le régime temporel qu’on associe au bonheur.

Currently, parental care is becoming increasingly perceived as male and female cooperation, instead of being primarily shaped by sexual conflict. Most studies examining cooperating performance consider coordination of parental activities, and doing so focuses on a short time-window including only one stage of breeding (i.e., incubation or chick rearing period). Here, we considered the cooperation of breeding partners, investigating the coordination of parental care in a long-lived seabird species with long and extensive biparental care, the Dovekie (or Little Auk), Alle alle, and looked at the issue throughout the breeding season. Previous studies on this species revealed coordinated chick provisioning, but parental coordination during incubation remains unstudied. Using video recordings collected over the course of two breeding seasons, we tested whether coordination was subject to small-scale changes within each stage and whether there was a relationship between coordination levels across the two stages. We found that the level of parental coordination is overall high and increases during the incubation period but decreases through the chick rearing phases. There were some inter-annual differences in the coordination level both at the incubation and chick rearing stages. We also found some dependency between the coordination during the incubation and chick rearing periods. All these results suggest that coordination is not a fixed behavior but breeding-phase dependent. The present study thus provides insights into how parental care and parents' cooperation is shaped by brood needs and conditions. It also highlights a relationship between coordination levels during chick rearing and incubation periods, suggesting some extent of temporal dependence in coordination of parental performance within the breeding season.

ABSTRACT In mammals, myrmecophagy (ant and termite consumption) represents a striking example of dietary convergence. This trait evolved independently at least five times in placentals with myrmecophagous species comprising aardvarks, anteaters, some armadillos, pangolins, and aardwolves. The gut microbiome plays an important role in dietary adaptation, and previous analyses of 16S rRNA metabarcoding data have revealed convergence in the composition of the gut microbiota among some myrmecophagous species. However, the functions performed by these gut bacterial symbionts and their potential role in the digestion of prey chitinous exoskeletons remain open questions. Using long- and short-read sequencing of fecal samples, we generated 29 gut metagenomes from nine myrmecophagous and closely related insectivorous species sampled in French Guiana, South Africa, and the United States. From these, we reconstructed 314 high-quality bacterial genome bins of which 132 carried chitinase genes, highlighting their potential role in insect prey digestion. These chitinolytic bacteria belonged mainly to the family Lachnospiraceae, and some were likely convergently recruited in the different myrmecophagous species as they were detected in several host orders (i.e., Enterococcus faecalis, Blautia sp.), suggesting that they could be directly involved in the adaptation to myrmecophagy. Others were found to be more host-specific, possibly reflecting phylogenetic constraints and environmental influences. Overall, our results highlight the potential role of the gut microbiome in chitin digestion in myrmecophagous mammals and provide the basis for future comparative studies performed at the mammalian scale to further unravel the mechanisms underlying the convergent adaptation to myrmecophagy. Importance Myrmecophagous mammals are specialized in the consumption of ants and/or termites. They do not share a direct common ancestor and evolved convergently in five distinct placental orders raising questions about the underlying adaptive mechanisms involved and the relative contribution of natural selection and phylogenetic constraints. Understanding how these species digest their prey can help answer these questions. More specifically, the role of their gut microbial symbionts in the digestion of the insect chitinous exoskeleton has not been investigated in all myrmecophagous orders. We generated 29 new gut metagenomes from nine myrmecophagous species to reconstruct more than 300 bacterial genomes in which we identified chitin-degrading enzymes. Studying the distribution of these chitinolytic bacteria among hosts revealed both shared and specific bacteria between ant-eating species. Overall, our results highlight the potential role of gut symbionts in the convergent dietary adaptation of myrmecophagous mammals and the evolutionary mechanisms shaping their gut microbiota.

The key characteristics (KC) of human carcinogens provide a uniform approach to evaluating mechanistic evidence in cancer hazard identification. Refinements to the approach were requested by organizations and individuals applying the KCs. We assembled an expert committee with knowledge of carcinogenesis and experience in applying the KCs in cancer hazard identification. We leveraged this expertise and examined the literature to more clearly describe each KC, identify current and emerging assays and in vivo biomarkers that can be used to measure them, and make recommendations for future assay development. We found that the KCs are clearly distinct from the Hallmarks of Cancer, that interrelationships among the KCs can be leveraged to strengthen the KC approach (and an understanding of environmental carcinogenesis), and that the KC approach is applicable to the systematic evaluation of a broad range of potential cancer hazards in vivo and in vitro We identified gaps in coverage of the KCs by current assays. Future efforts should expand the breadth, specificity, and sensitivity of validated assays and biomarkers that can measure the 10 KCs. Refinement of the KC approach will enhance and accelerate carcinogen identification, a first step in cancer prevention.See all articles in this CEBP Focus section, "Environmental Carcinogenesis: Pathways to Prevention."

There is a general consensus on the need for agroecological scaling up as an alternative to the crisis generated by the unsustainability of the industrial agriculture model and even more so in the current context of a health pandemic. However, the transition from conventional to agroecological production is a theoretical, methodological and practical challenge, since it implies generating lasting changes in the thoughts, feelings and actions of human beings. In this paper we explore how the breeding of native bees favors the learning of agroecology in Nicaragua. The breeding of native bees is an ancestral practice in Nicaragua, however, it is at risk due to landscape degradation and cultural changes. Through participatory action-research in the department of Carazo, we document how the demands of meliponiculture become motivating elements for advancing agroecological principles. Learning to raise native stingless bees is a slow, daily, active process that changes individuals and the landscape. This work identifies the way in which an element of the territory itself becomes a device that favors agroecological change, in correspondence with local knowledge, spirituality and culture.

Abstract Factors that increase estrogen or progesterone (P4) action are well-established as increasing breast cancer risk, and many first-line treatments to prevent breast cancer recurrence work by blocking estrogen synthesis or action. In previous work, using data from an in vitro steroidogenesis assay developed for the U.S. Environmental Protection Agency (EPA) ToxCast program, we identified 182 chemicals that increased estradiol (E2up) and 185 that increased progesterone (P4up) in human H295R adrenocortical carcinoma cells, an OECD validated assay for steroidogenesis. Chemicals known to induce mammary effects in vivo were very likely to increase E2 or P4 synthesis, further supporting the importance of these pathways for breast cancer. To identify additional chemical exposures that may increase breast cancer risk through E2 or P4 steroidogenesis, we developed a cheminformatics approach to identify structural features associated with these activities and to predict other E2 or P4 steroidogens from their chemical structures. First, we used molecular descriptors and physicochemical properties to cluster the 2,012 chemicals screened in the steroidogenesis assay using a self-organizing map (SOM). Structural features such as triazine, phenol, or more broadly benzene ramified with halide, amine or alcohol, are enriched for E2 or P4up chemicals. Among E2up chemicals, phenol and benzenone are found as significant substructures, along with nitrogen-containing biphenyls. For P4up chemicals, phenol and complex aromatic systems ramified with oxygen-based groups such as flavone or phenolphthalein are significant substructures. Chemicals that are active for both E2up and P4up are enriched with substructures such as dihydroxy phosphanedithione or are small chemicals that contain one benzene ramified with chlorine, alcohol, methyl or primary amine. These results are confirmed with a chemotype ToxPrint analysis. Then, we used machine learning and artificial intelligence algorithms to develop and validate predictive classification QSAR models for E2up and P4up chemicals. These models gave reasonable external prediction performances (balanced accuracy ~ 0.8 and Matthews Coefficient Correlation ~ 0.5) on an external validation. The QSAR models were enriched by adding a confidence score that considers the chemical applicability domain and a ToxPrint assessment of the chemical. This profiling and these models may be useful to direct future testing and risk assessments for chemicals related to breast cancer and other hormonally-mediated outcomes.

Thomas Borrel, member of the Survie association, and Thomas Deltombe, editor, are independent researchers and co-authors (with Amzat Boukari-Yabara and Benoît Collombat) of L’Empire qui ne veut pas mourir. Une histoire de la Françafrique, published by Seuil in October 2021. This collective work of nearly 1000 pages offers an unprecedented synthesis of the history of a system of domination whose study remains marginal in the academic world. Considered over a long time period, these neocolonial relations show, according to the thesis defended by the authors, an astonishing capacity to adapt in order to endure, despite the proclamations of rupture or the appearance of disintegration.

Background: In modern rhinoplasty there are new concepts aimed at achieving the ideal model of a nose. Many techniques have become old, but new, less invasive ones have emerged.Objective: to describe the results of rhinoplasty using the autograft relocation technique in patients with nasal deformities.Methods: a descriptive case series study conducted at the Dr. Gustavo Aldereguía Lima General University Hospital, in Cienfuegos. 25 patients were included in the research, who attended the Maxillofacial Surgery consultation due to nasal deformities, between 2009 and 2019, to whom the rhinoplasty surgical technique (the modified Joseph technique) was applied. Age, sex, skin color, type of graft, technique used (endonasal, open) and type of anesthesia were analyzed.Results: female sex and white skin color predominated. The most used surgical technique was endonasal (20 patients). All were operated under local anesthesia. The largest age group was 15-30 years old. The osteocartilaginous hump was the graft used in 72% of the cases.Conclusion: with the autograft relocation technique, favorable results were obtained in the case series described. This is one of the most advanced in the context of nasal cosmetic surgery.

O projeto Mirada de Barrio (Visão do Bairro) foi desenvolvido pelo Museo de la Solidaridad Salvador Allende entre os anos 2017 e 2019, com a finalidade de estabelecer um novo vínculo entre o museu e o bairro onde está localizado: o bairro República, da cidade de Santiago do Chile. Neste texto abordamos as modalidades de produção do território envolvidas no conjunto de ações implementadas no âmbito desse projeto. Com isso, buscamos contribuir para uma discussão na qual comummente se esquece que o território também é uma realidade sensível e que, consequentemente, importa incluí-lo entre os focos de observação da mediação artística dado que aí se expressa um de seus efeitos mais poderosos. Nossa metodologia é baseada na sistematização de experiências e em ferramentas provenientes da autoetnografia, através das quais analisamos a participação direta de um dos autores no processo. Afirmamos que o projeto Mirada de Barrio permitiu a abertura na construção coletiva do território, rompendo a partilha do sensível que se manifesta em formas de sociabilidade caracterizadas pela desconfiança, o descaso a outras formas de apropriação que não sejam a propriedade privada e a desconexão afetiva com o território que é habitado. Desta forma, o novo vínculo entre bairro e museu gerado por um processo de participação efetivo desencadeia práticas de convivência e cooperação através das quais se expressa uma nova forma de coprodução territorial que considera elementos sensíveis e afetivos, antes não conscientemente considerados pelos habitantes na sua vida cotidiana de bairro.

Methanogenesis is an ancient metabolism of key ecological relevance, with direct impact on the evolution of Earth's climate. Recent results suggest that the diversity of methane metabolisms and their derivations have probably been vastly underestimated. Here, by probing thousands of publicly available metagenomes for homologues of methyl-coenzyme M reductase complex (MCR), we have obtained ten metagenome-assembled genomes (MAGs) belonging to potential methanogenic, anaerobic methanotrophic and short-chain alkane-oxidizing archaea. Five of these MAGs represent under-sampled (Verstraetearchaeota, Methanonatronarchaeia, ANME-1 and GoM-Arc1) or previously genomically undescribed (ANME-2c) archaeal lineages. The remaining five MAGs correspond to lineages that are only distantly related to previously known methanogens and span the entire archaeal phylogeny. Comprehensive comparative annotation substantially expands the metabolic diversity and energy conservation systems of MCR-bearing archaea. It also suggests the potential existence of a yet uncharacterized type of methanogenesis linked to short-chain alkane/fatty acid oxidation in a previously undescribed class of archaea ('Candidatus Methanoliparia'). We redefine a common core of marker genes specific to methanogenic, anaerobic methanotrophic and short-chain alkane-oxidizing archaea, and propose a possible scenario for the evolutionary and functional transitions that led to the emergence of such metabolic diversity.

Here, by analyzing 250 species of animals covering a large taxonomic spectrum, the authors show that archaea are common constituent of the animal gut throughout the animal kingdom, and identify six main genera/families of gut archaea revealing their abundance and diversity to be driven by host diet, evolutionary history and physiology.

Abstract Investigating ecology of marine animals imposes a continuous challenge due to their temporal and/or spatial unavailability. Light‐based geolocators (GLS) are animal‐borne devices that provide relatively cheap and efficient method to track seabird movement and are commonly used to study migration. Here, we explore the potential of GLS data to establish individual behavior during the breeding period in a rock crevice‐nesting seabird, the Little Auk, Alle alle. By deploying GLS on 12 breeding pairs, we developed a methodological workflow to extract birds' behavior from GLS data (nest attendance, colony attendance, and foraging activity), and validated its accuracy using behavior extracted from a well‐established method based on video recordings. We also compared breeding outcome, as well as behavioral patterns of logged individuals with a control group treated similarly in all aspects except for the deployment of a logger, to assess short‐term logger effects on fitness and behavior. We found a high accuracy of GLS‐established behavioral patterns, especially during the incubation and early chick rearing period (when birds spend relatively long time in the nest). We observed no apparent effect of logger deployment on breeding outcome of logged pairs, but recorded some behavioral changes in logged individuals (longer incubation bouts and shorter foraging trips). Our study provides a useful framework for establishing behavioral patterns (nest attendance and foraging) of a crevice‐nesting seabird from GLS data (light and conductivity), especially during incubation and early chick rearing period. Given that GLS deployment does not seem to affect the breeding outcome of logged individuals but does affect fine‐scale behavior, our framework is likely to be applicable to a variety of crevice/burrow nesting seabirds, even though precautions should be taken to reduce deployment effect. Finally, because each species may have its own behavioral and ecological specificity, we recommend performing a pilot study before implementing the method in a new study system.

Currently, parental care is becoming increasingly perceived as male and female cooperation, instead of being primarily shaped by sexual conflict. Most studies examining cooperating performance consider coordination of parental activities, and doing so focuses on a short time-window including only one stage of breeding (i.e., incubation or chick rearing period). Here, we considered the cooperation of breeding partners, investigating the coordination of parental care in a long-lived seabird species with long and extensive biparental care, the Dovekie (or Little Auk), Alle alle, and looked at the issue throughout the breeding season. Previous studies on this species revealed coordinated chick provisioning, but parental coordination during incubation remains unstudied. Using video recordings collected over the course of two breeding seasons, we tested whether coordination was subject to small-scale changes within each stage and whether there was a relationship between coordination levels across the two stages. We found that the level of parental coordination is overall high and increases during the incubation period but decreases through the chick rearing phases. There were some inter-annual differences in the coordination level both at the incubation and chick rearing stages. We also found some dependency between the coordination during the incubation and chick rearing periods. All these results suggest that coordination is not a fixed behavior but breeding-phase dependent. The present study thus provides insights into how parental care and parents' cooperation is shaped by brood needs and conditions. It also highlights a relationship between coordination levels during chick rearing and incubation periods, suggesting some extent of temporal dependence in coordination of parental performance within the breeding season. [ABSTRACT FROM AUTHOR]

The methanogenic strain Mx-05T was isolated from the human fecal microbiome. A phylogenetic analysis based on the 16S rRNA gene and protein marker genes indicated that the strain is affiliated with the order Methanomassiliicoccales. It shares 86.9% 16S rRNA gene sequence identity with Methanomassiliicoccus luminyensis, the only member of this order previously isolated. The cells of Mx-05T were non-motile cocci, with a diameter range of 0.4–0.7 μm. They grew anaerobically and reduced methanol, monomethylamine, dimethylamine, and trimethylamine into methane, using H2 as an electron donor. H2/CO2, formate, ethanol, and acetate were not used as energy sources. The growth of Mx-05T required an unknown medium factor(s) provided by Eggerthella lenta and present in rumen fluid. Mx-05T grew between 30 °C and 40 °C (optimum 37 °C), over a pH range of 6.9–8.3 (optimum pH 7.5), and between 0.02 and 0.34 mol.L−1 NaCl (optimum 0.12 mol.L−1 NaCl). The genome is 1.67 Mbp with a G+C content of 55.5 mol%. Genome sequence annotation confirmed the absence of the methyl branch of the H4MPT Wood–Ljungdahl pathway, as described for other Methanomassiliicoccales members. Based on an average nucleotide identity analysis, we propose strain Mx-05T as being a novel representative of the order Methanomassiliicoccales, within the novel family Methanomethylophilaceae, for which the name Methanomethylophilus alvi gen. nov, sp. nov. is proposed. The type strain is Mx-05T (JCM 31474T).

Le Musée à ciel ouvert de San Miguel est une initiative lancée en 2010 par des habitant·e·s du quartier du même nom, dans le but de contrer la détérioration de l’environnement ainsi que la pression des entreprises immobilières. Dans le présent texte, nous nous intéressons à la création et au développement de ce musée dans une optique de production de citoyenneté. Nous proposons d’envisager ce phénomène comme un cas d’« extension du processus d’inclusion » (Sassen, 2003 : 64) qui interviendrait dans les dynamiques matérielles et symboliques de l’inégalité urbaine au Chili. Cette inclusion expansive favoriserait la revitalisation des relations au sein de la population. La méthodologie consiste en la réalisation de trente-cinq entretiens individuels, six entretiens de groupe, trois accompagnements à des visites guidées d’étudiant·e·s ainsi qu’en une cartographie des investissements et une cartographie des oeuvres murales du quartier. En nous appuyant sur les informations tirées de cette recherche, nous concluons que le Musée à ciel ouvert de San Miguel correspond à une nouvelle manière de composer le territoire du quartier, dans la mesure où ce musée a permis l’émergence de nouveaux modes d’interaction chez ses habitant·e·s, de nouvelles dynamiques de relation à l’égard du milieu dans lequel il se trouve ainsi que de nouvelles formes de reconnaissance qui dérogent aux stigmates habituels associés aux quartiers pauvres de Santiago de Chile.