On the microstructure, growth pattern and original porosity of belemnite rostra: insights from calcitic Jurassic belemnites

Calcitic belemnite rostra are usually employed to perform paleoenvironmental studies based on geochemical data. However, several questions, such as their original porosity and microstructure, remain open, despite they are essential to make accurate interpretations based on geochemical analyses.This paper revisits and enlightens some of these questions. Petrographic data demonstrate that calcite crystals of the rostrum solidum of belemnites grow from spherulites that successively develop along the apical line, resulting in a “regular spherulithic prismatic” microstructure. Radially arranged calcite crystals emerge and diverge from the spherulites: towards the apex, crystals grow until a new spherulite is formed; towards the external walls of the rostrum, the crystals become progressively bigger and prismatic. Adjacent crystals slightly vary in their c-axis orientation, resulting in undulose extinction. Concentric growth layering develops at different scales and is superimposed and traversed by a radial pattern, which results in the micro-fibrous texture that is observed in the calcite crystals in the rostra.Petrographic data demonstrate that single calcite crystals in the rostra have a composite nature, which strongly suggests that the belemnite rostra were originally porous. Single crystals consistently comprise two distinct zones or sectors in optical continuity: 1) the inner zone is fluorescent, has relatively low optical relief under transmitted light (TL) microscopy, a dark-grey color under backscatter electron microscopy (BSEM), a commonly triangular shape, a “patchy” appearance and relatively high Mg and Na contents; 2) the outer sector is non-fluorescent, has relatively high optical relief under TL, a light-grey color under BSEM and low Mg and Na contents. The inner and fluorescent sectors are interpreted to have formed first as a product of biologically controlled mineralization during belemnite skeletal growth and the non-fluorescent outer sectors as overgrowths of the former, filling the intra- and inter-crystalline porosity. This question has important implications for making paleoenvironmental and/or paleoclimatic interpretations based on geochemical analyses of belemnite rostra.Finally, the petrographic features of composite calcite crystals in the rostra also suggest the non-classical crystallization of belemnite rostra, as previously suggested by other authors.

LATERAL BRANCHING OXIDOREDUCTASE acts in the final stages of strigolactone biosynthesis inArabidopsis

Strigolactones are a group of plant compounds of diverse but related chemical structures. They have similar bioactivity across a broad range of plant species, act to optimize plant growth and development, and promote soil microbe interactions. Carlactone, a common precursor to strigolactones, is produced by conserved enzymes found in a number of diverse species. Versions of the MORE AXILLARY GROWTH1 (MAX1) cytochrome P450 from rice and Arabidopsis thaliana make specific subsets of strigolactones from carlactone. However, the diversity of natural strigolactones suggests that additional enzymes are involved and remain to be discovered. Here, we use an innovative method that has revealed a missing enzyme involved in strigolactone metabolism. By using a transcriptomics approach involving a range of treatments that modify strigolactone biosynthesis gene expression coupled with reverse genetics, we identified LATERAL BRANCHING OXIDOREDUCTASE (LBO), a gene encoding an oxidoreductase-like enzyme of the 2-oxoglutarate and Fe(II)-dependent dioxygenase superfamily. Arabidopsis lbo mutants exhibited increased shoot branching, but the lbo mutation did not enhance the max mutant phenotype. Grafting indicated that LBO is required for a graft-transmissible signal that, in turn, requires a product of MAX1. Mutant lbo backgrounds showed reduced responses to carlactone, the substrate of MAX1, and methyl carlactonoate (MeCLA), a product downstream of MAX1. Furthermore, lbo mutants contained increased amounts of these compounds, and the LBO protein specifically converts MeCLA to an unidentified strigolactone-like compound. Thus, LBO function may be important in the later steps of strigolactone biosynthesis to inhibit shoot branching in Arabidopsis and other seed plants.

Seed layer technique for high quality epitaxial manganite films

We introduce an innovative approach to the simultaneous control of growth mode and magnetotransport properties of manganite thin films, based on an easy-to-implement film/substrate interface engineering. The deposition of a manganite seed layer and the optimization of the substrate temperature allows a persistent bi-dimensional epitaxy and robust ferromagnetic properties at the same time. Structural measurements confirm that in such interface-engineered films, the optimal properties are related to improved epitaxy. A new growth scenario is envisaged, compatible with a shift from heteroepitaxy towards pseudo-homoepitaxy. Relevant growth parameters such as formation energy, roughening temperature, strain profile and chemical states are derived.

Non-hierarchical cluster analysis for body weight, age at first egg, egg production and egg weight in a laying hen strain.

2016

Na 50 Nachlass Arthur Schopenhauer - 'Schopenhauer-Archiv', 520 - Konzept einer Instruktion f��r den Mandatarius Georg Carl Friedrich Kunowski in der Sache Marquet

u.a.: Carolin Marquet; Carolin Médon; Dorothea Marie Becker; G. R. Schmalz;

Deutsche acta eruditorum, oder, Geschichte der Gelehrten, welche den gegenwärtigen Zustand der Literatur in Europa begreiffen.

Description based on: 2. T. Library's copy of 1. T. lacks t.p.

Friedrich Heinrich Jacobi's werke.

Mode of access: Internet.

New genetic loci link adipose and insulin biology to body fat distribution

Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10−8). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms.

Directional dominance on stature and cognition in diverse human populations

Homozygosity has long been associated with rare, often devastating, Mendelian disorders1, and Darwin was one of the first to recognize that inbreeding reduces evolutionary fitness2. However, the effect of the more distant parental relatedness that is common in modern human populations is less well understood. Genomic data now allow us to investigate the effects of homozygosity on traits of public health importance by observing contiguous homozygous segments (runs of homozygosity), which are inferred to be homozygous along their complete length. Given the low levels of genome-wide homozygosity prevalent in most human populations, information is required on very large numbers of people to provide sufficient power3, 4. Here we use runs of homozygosity to study 16 health-related quantitative traits in 354,224 individuals from 102 cohorts, and find statistically significant associations between summed runs of homozygosity and four complex traits: height, forced expiratory lung volume in one second, general cognitive ability and educational attainment (P < 1 × 10−300, 2.1 × 10−6, 2.5 × 10−10 and 1.8 × 10−10, respectively). In each case, increased homozygosity was associated with decreased trait value, equivalent to the offspring of first cousins being 1.2 cm shorter and having 10 months’ less education. Similar effect sizes were found across four continental groups and populations with different degrees of genome-wide homozygosity, providing evidence that homozygosity, rather than confounding, directly contributes to phenotypic variance. Contrary to earlier reports in substantially smaller samples5, 6, no evidence was seen of an influence of genome-wide homozygosity on blood pressure and low density lipoprotein cholesterol, or ten other cardio-metabolic traits. Since directional dominance is predicted for traits under directional evolutionary selection7, this study provides evidence that increased stature and cognitive function have been positively selected in human evolution, whereas many important risk factors for late-onset complex diseases may not have been.

New genetic loci link adipose and insulin biology to body fat distribution

Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms.

Staatstätigkeiten, Parteien und Demokratie. Festschrift f��r Manfred G. Schmidt

Manfred G. Schmidt ist einer der f��hrenden Politikwissenschaftler Europas. Drei Themen bilden Schwerpunkte in seinem reichhaltigen Werk. Machen Parteien einen Unterschied f��r das staatliche Handeln? Diese Frage bildet den ersten Schwerpunkt seines Schaffens: In welchen Politikbereichen und unter welchen Bedingungen schlägt sich die Regierungsbeteiligung einer Partei in unterschiedlichen Staatstätigkeiten nieder? Der zweite Schwerpunkt ist die Demokratietheorie. Hier geht es ihm um eine vergleichende Rekonstruktion und Evaluation der verschiedenen Demokratietheorien. Die Arbeiten von Manfred G. Schmidt sind grundsätzlich international vergleichend angelegt. Dennoch galt seine besondere Aufmerksamkeit den politischen Systemen Deutschlands. Dies ist der dritte Schwerpunkt. Die Analyse der politischen Institutionen, des Parteienwettbewerbs und der wohlfahrtsstaatlichen Entwicklung in Deutschland seit dem 19. Jahrhundert waren Gegenstand von vielen Monographien und Aufsätzen. Er betonte insbesondere die Interaktionen von Institutionen und Parteien, die die Bundesrepublik Deutschland auf einem ‚mittleren Weg��� hielten – und schloss damit sowohl an seine international vergleichenden Analysen der Sozial-, Wirtschafts-, Bildungs- und Arbeitsmarktpolitik als auch an seine demokratietheoretischen Überlegungen an. Die Beiträge der Festschrift setzen sich mit dem Werk von Manfred G. Schmidt auseinander. Sie würdigen kritisch seine Verdienste, nehmen seine Befunden und Fragestellungen auf und f��hren sie in empirischen oder theoretisch-konzeptionellen Analysen weiter.

Na 50 Nachlass Arthur Schopenhauer - 'Schopenhauer-Archiv', 519 - Konzept einer Instruktion f��r den Mandatarius Georg Carl Friedrich Kunowski in der Sache Marquet

u.a.: Carolin Marquet; Carolin Médon;

Na 50 Nachlass Arthur Schopenhauer - 'Schopenhauer-Archiv', 564 - Mitteilung von Georg Carl Friedrich Kunowski an Mendelsohn & Fraenckel wegen der Sache Marquet

u.a.: Einsichtnahme in die Gerichtsakten; behauptete Unzulässigkeit der Klage;

Na 50 Nachlass Arthur Schopenhauer - 'Schopenhauer-Archiv', 565 - Zustellung des Schreibens von Georg Carl Friedrich Kunowski zur Kenntnisnahme durch das Berliner Bankhaus Mendelssohn & Fraenckel

2 Seiten