The tRNATyr multigene family of Triticum aestivum: genome organization, sequence analyses and maturation of intron-containing pre-tRNAs in wheat germ extract

AbstractSouthern analysis of Triticum DNA has revealed that nuclear tRNATyr genes are dispersed at a minimum of 16 loci in the genome. We have isolated six independent tRNATyr genes from a Triticum aestivum library in addition to three known members of the Triticum tRNATyr family. Four of the sequenced tRNATyr genes code for Triticum tRNA1Tyr and two code for tRNA2Tyr. Three genes encode tRNATyr which carry one or two nucleotide substitutions as compared to the conventional genes. The nine Triticum tRNATyr genes possess highly conserved intron sequences ranging in size from 12 to 14 nucleotides. A common secondary intron structure with the 5′ and 3′ splice site loops separated by five base pairs can be formed by all pre-tRNAsTyr which are efficiently spliced in the homologous wheat germ extract

Within-Family Environment and Cross-Fostering Stress Affect Behavior and Physiology in Wild Cavies (Cavia aperea)

Kraus S, Trillmich F, Günther A. Within-Family Environment and Cross-Fostering Stress Affect Behavior and Physiology in Wild Cavies (Cavia aperea). Frontiers in Psychology. 2020;11: 178.Stability of personality traits is well-documented for a wide variety of animals. However, previous results also suggest that behavioral phenotypes are plastic during early ontogeny and can be adaptively shaped to the social environment. In cavies (Cavia aperea), it has already been documented that the size at birth relative to siblings (size rank) greatly influences various behavioral and physiological traits that last at least until independence. The aim of the current study was (1) to investigate if behavioral and physiological differences between pups of the same litter persist until after independence and influence development long-lasting, (2) to determine the potential plasticity in response to changes in the early within-family environment by cross-fostering pups either to the same, a lower, or a higher size rank in a foster-family. We measured three behavioral traits (number of interactions with a novel object, distance moved in an open field, struggle docility) and two physiological traits (resting metabolic rate and basal cortisol levels). We predicted that cross-fostering into a litter where pups occupy the same size rank would not change the expression of traits. Cross-fostering to a different size rank should not influence the expression of traits if repeatability measures indicate low plasticity. Alternatively, if the traits are plastic, animals should adjust trait expression to fit with the size rank occupied in the foster litter. Initial differences in struggle docility, distance moved in an open field and in baseline cortisol concentration between pups of different size-ranks did not remain stable beyond independence. In addition, we found remarkable plasticity of the measured traits in response to cross-fostering to the same, a smaller or larger size-rank, suggesting that differences between pups are more the result of social constraints leading to adaptive shaping of individual phenotypes within a family. We also found a significant influence of the cross-fostering procedure itself. Cross-fostered individuals were less bold, grew slower and showed elevated resting metabolic rates. This finding suggests a cautious interpretation of previous cross-fostering studies and stresses the need for proper control groups to reliably separate the effect of cross-fostering per se from those induced by an experimental treatment. Introductio

Les voyages et lettres de correspondance de John Ray, ou l’émergence des sciences naturelles dans l’Europe du xviie siècle

John Ray (1627-1705), éminent naturaliste né à l’aube de la Révolution scientifique, a rencontré et entretenu des correspondances avec de nombreux savants de l’Europe. Considéré comme le fondateur de la botanique et de la zoologie modernes, John Ray, surnommé le « Pline anglais », est le premier à proposer un concept précis de la notion d’espèce. À travers sa correspondance, se dessine un réseau d’échanges collaboratifs et amicaux participant à la construction collective des sciences naturelles. Ses Lettres Philosophiques nous font découvrir le contexte historique et culturel dans lequel ce savoir s’est élaboré, dans le milieu intellectuel protestant où la théologie et la science sont étroitement liées au xviie siècle. Bastion huguenot doté du premier Jardin du Roy de France, Montpellier était devenue la « capitale de la botanique » et attirait les naturalistes de toute l’Europe. John Ray et ses amis viendront y rencontrer Pierre Magnol. Membre de la Royal Society, Ray s’engagera également dans la publication d’ouvrages adressés à un large public : collections de proverbes et de mots, manuels scolaires et dictionnaires en langues vernaculaires

Jean-André Deluc (1727-1817) et la montagne comme objet d’étude et norme éthique

Les montagnes ont longtemps été considérées comme des monuments terribles du sacrilège humain. Une transformation de cette perception s’opère dans le milieu intellectuel protestant britannique au xviie siècle. Les montagnes apparaissent alors comme un ouvrage d’art animant un sentiment de beauté. Issu d’une famille calviniste genevoise, Jean-André Deluc et son frère Guillaume-Antoine font partie des premiers savants à explorer les Alpes. Jouissant d’une grande renommée de son vivant, Deluc a été longtemps discrédité, car il cherchait à concilier ses travaux scientifiques avec la Genèse. Le résultat de vingt ans d’explorations météorologiques en haute montagne est publié dans Recherches sur les modifications de l’atmosphère. C’est un recueil d’observations de terrain et d’expériences empiriques, afin de perfectionner les instruments et les méthodes d’investigation dans les mesures altimétriques. Ce recueil nous révèle aussi tout un versant d’études anthropologiques sur le genre de vie des habitants des montagnes, sur le savoir-faire des artisans. Les travaux de Deluc exercèrent une grande influence sur Horace-Bénédict de Saussure et Georges Cuvier

L’aristotélisme christianisé dans la théologie naturelle des xviie et xviiie siècles

Le christianisme a été longtemps le lieu d’une opposition fondamentale entre l’homme et l’animal, postulant la supériorité de l’humain placé au sommet de la création, et dominant la terre et les animaux. Or, l’alliance entre la religion et l’histoire naturelle au xviie siècle a réintroduit l’homme dans la nature, grâce à la théologie naturelle issue de la Réforme. Longtemps considéré comme marginal, c’est en fait un mouvement intellectuel qui a eu un rôle fondamental à l’échelle européenne dans l’émergence de la science moderne. L’œuvre du médecin et pasteur anglais William Derham (1657-1735) participe de l’alliance féconde entre la biologie générale d’Aristote et l’appréciation judéo-chrétienne de la nature comme intrinsèquement bonne. L’approche écologique et planétaire de sa Théologie physique montre à l’homme qu’il n’est qu’une des Créatures admirables de l’Auteur de la Nature, une Nature avec laquelle il est en lien et dont il est irrémédiablement dépendant

Adult Zebrafish as a Model System for Cutaneous Wound-Healing Research

Upon injury, the skin must quickly regenerate to regain its barrier function. In mammals, wound healing is rapid and scar free during embryogenesis, whereas in adults it involves multiple steps including blood clotting, inflammation, re-epithelialization, vascularization, and granulation tissue formation and maturation, resulting in a scar. We have established a rapid and robust method to introduce full-thickness wounds onto the flank of adult zebrafish, and show that apart from external fibrin clot formation, all steps of adult mammalian wound repair also exist in zebrafish. Wound re-epithelialization is extremely rapid and initiates with no apparent lag phase, subsequently followed by the immigration of inflammatory cells and the formation of granulation tissue, consisting of macrophages, fibroblasts, blood vessels, and collagen. The granulation tissue later regresses, resulting in minimal scar formation. Studies after chemical treatment or with transgenic fish further suggest that wound re-epithelialization occurs independently of inflammation and fibroblast growth factor signaling, whereas both are essential for fibroblast recruitment and granulation tissue formation. Together, these results demonstrate that major steps and principles of cutaneous wound healing are conserved among adult mammals and adult zebrafish, making zebrafish a valuable model for studying vertebrate skin repair

No aggregate deforestation reductions from rollout of community land titles in Indonesia yet

In Indonesia, 60 million people live within 1 km of state forest. The government of Indonesia plans to grant community titles for 12.7 million hectares of land to communities living in and around forests. These titles allow for using nontimber forest products, practicing agroforestry, operating tourism businesses, and selective logging in designated production zones. Here, we estimate the early effects of the program’s rollout. We use data on the delineation and introduction date of community forest titles on 2.4 million hectares of land across the country. We find that, contrary to the objective of the program, community titles aimed at conservation did not decrease deforestation; if anything, they tended to increase forest loss. In contrast, community titles in zones aimed at timber production decreased deforestation, albeit from higher baseline forest loss rates

Integrated model of the vertebrate augmin complex

Accurate segregation of chromosomes is required to maintain genome integrity during cell division. This feat is accomplished by the microtubule-based spindle. To build a spindle rapidly and with high fidelity, cells take advantage of branching microtubule nucleation, which rapidly amplifies microtubules during cell division. Branching microtubule nucleation relies on the hetero-octameric augmin complex, but lack of structure information about augmin has hindered understanding how it promotes branching. In this work, we combine cryo-electron microscopy, protein structural prediction, and visualization of fused bulky tags via negative stain electron microscopy to identify the location and orientation of each subunit within the augmin structure. Evolutionary analysis shows that augmin\u27s structure is highly conserved across eukaryotes, and that augmin contains a previously unidentified microtubule binding site. Thus, our findings provide insight into the mechanism of branching microtubule nucleation

Doing transnational family im Kontext von Flucht und Krisenmigration: Stand der Forschung

In den vergangenen Jahren ist die Zahl gewaltsam Vertriebener stetig gestiegen, und auch die Anzahl der Menschen, die in weiter entfernte Staaten fliehen, hat laut UNHCR weltweit stark zugenommen. In Deutschland wurden im Zeitraum von 2015 bis 2017 fast 1,4 Mio. Asylerstanträge gestellt, hauptsächlich von Menschen aus Syrien, Afghanistan, Irak sowie Eritrea. Aufgrund der Aktualität des Themas hat sich seit Kurzem eine eigen-ständige Forschung zu Flucht und Geflüchteten in Deutschland entwickelt, wobei sich die deutsche Forschungslandschaft über die Disziplinen hinweg vor allem auf die Themen Aufnahme und Teilhabe von Geflüchteten in Deutschland konzentriert. Bisher gibt es nur sehr wenige Arbeiten, die sich mit Familien von Geflüchteten auseinandersetzen, obwohl unbestritten ist, dass Familien sowohl für die Migrationsentscheidung als auch für die Integration und Teilhabe im Zielland eine wichtige Rolle spielen. In Vorbereitung auf eine eigene empirische Studie, die diese Forschungslücke schließen möchte, wurde das vorliegende Working Paper erstellt. Es fasst die internationale Literatur zu den Fragen nach der Entstehung, Beibehaltung und Veränderung von transnationalen Familien, den transnationalen Alltagspraktiken sowie Unterstützungsleistungen und den Konsequenzen von Transnationalität auf die Beziehungsstabilität und -qualität zwischen Partnern, Kindern und Eltern sowie deren (subjektivem) Wohlbefinden, Einstellungen und Geschlechterrollen zusammen. Das Working Paper versucht darüber hinaus, die Anschlussfähigkeit der vorliegenden Studien zu transnationalen Familien auf den Fluchtkontext herzustellen und Forschungslücken im Themenfeld transnationaler Familien und Fluchtmigration aufzuzeigen

Experimental multi-level seismic performance assessment of 3D RC frame designed for damage avoidance

This paper experimentally investigates the application of damage avoidance design (DAD) philosophy to moment-resisting frames with particular emphasis on detailing of rocking interfaces. An 80% scale three-dimensional rocking beam-column joint sub-assembly designed and detailed based on damage avoidance principles is constructed and tested. Incremental dynamic analysis is used for selecting ground motion records to be applied to the sub-assembly for conducting a multi-level seismic performance assessment (MSPA). Analyses are conducted to obtain displacement demands due to the selected near- and medium-field ground motions that represent different levels of seismic hazard. Thus, predicted displacement time histories are applied to the sub-assembly for conducting quasi-earthquake displacement tests. The sub-assembly performed well reaching drifts up to 4.7% with only minor spalling occurring at rocking beam interfaces and minor flexural cracks in beams. Yielding of post-tensioning threaded bars occurred, but the sub-assembly did not collapse. The externally attached energy dissipators provided large hysteretic dissipation during large drift cycles. The sub-assembly satisfied all three seismic performance requirements, thereby verifying the superior performance of the DAD philosoph