Seed conservation in ex situ genebanks - genetic studies on longevity in barley

Recognizing the danger due to a permanent risk of loss of the genetic variability of cultivated plants and their wild relatives in response to changing environmental conditions and cultural practices, plant ex situ genebank collections were created since the beginning of the last century. World-wide more than 6 million accessions have been accumulated of which more than 90% are stored as seeds. Research on seed longevity was performed in barley maintained for up to 34 years in the seed store of the German ex situ genebank of the Leibniz-Institute of Plant Genetics and Crop Plant Research in Gatersleben. A high intraspecific variation was detected in those natural aged accessions. In addition three doubled haploid barley mapping populations being artificial aged were investigated to study the inheritance of seed longevity. Quantitative trait locus (QTL) mapping was based on a transcript map. Major QTLs were identified on chromosomes 2H, 5H (two) and 7H explaining a phenotypic variation of up to 54%. A sequence homology search was performed to derive the putative function of the genes linked to the QTLs

Accessing the Next Generation of Synthetic Mussel‐Glue Polymers via Mussel‐Inspired Polymerization

The formation of cysteinyldopa as biogenic connectivity in proteins is used to inspire a chemical pathway toward mussel-adhesive mimics. The mussel-inspired polymerization (MIPoly) exploits the chemically diverse family of bisphenol monomers that is oxidizable with 2-iodoxybenzoic acid to give bisquinones. Those react at room temperature with dithiols in Michael-type polyadditions, which leads to polymers with thiol–catechol connectivities (TCC). A set of TCC polymers proved adhesive behavior even on challenging poly(propylene) substrates, where they compete with commercial epoxy resins in dry adhesive strength. MIPoly promises facile scale up and exhibits high modularity to tailor adhesives, as proven on a small library where one candidate showed wet adhesion on aluminum substrates in both water and sea water models.Verband der Chemischen Industrie http://dx.doi.org/10.13039/100007215Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659Peer Reviewe

Social inertia in collaboration networks

This work is a study of the properties of collaboration networks employing the formalism of weighted graphs to represent their one-mode projection. The weight of the edges is directly the number of times that a partnership has been repeated. This representation allows us to define the concept of "social inertia" that measures the tendency of authors to keep on collaborating with previous partners. We use a collection of empirical datasets to analyze several aspects of the social inertia: 1) its probability distribution, 2) its correlation with other properties, and 3) the correlations of the inertia between neighbors in the network. We also contrast these empirical results with the predictions of a recently proposed theoretical model for the growth of collaboration networks.Comment: 7 pages, 5 figure

56-jährige Patientin mit pathologischer subkapitaler Humerusfraktur bei Morbus Gaucher

Zusammenfassung: Wir berichten über eine Patientin mit pathologischer Humerusfraktur bei Erstdiagnose eines Morbus Gaucher, der häufigsten autosomal-rezessiv vererbten Lipidspeicherkrankheit. Sie führt häufig zu schweren Knochenkomplikationen mit Schmerzen, Osteonekrosen, Frakturen oder Gelenkeinbrüchen. Bei begründetem Verdacht sollte in Hinblick auf die therapeutischen Konsequenzen zur Diagnosesicherung die β-Glucocerebrosidase in Leukozyten bestimmt werden. Durch eine Enzymersatztherapie ist die Krankheit effektvoll behandelba

Insight into the genetic contribution of maximum yield potential, spikelet development and abortion in barley

Societal Impact Statement To feed the world's ever‐increasing population, new genetic approaches are required. Increasing the number of living spikelets is one promising way to improve grain yield. This, in turn, increases the number of spikelets per plant, thereby increasing the total yield. We present the first evidence for genetic control of alive spikelets in barley. Discovering natural variation as well as genomic regions associated with these traits will serve as a benchmark in future breeding for improving grain yield. Summary The primary goal of most breeding programmes is to increase grain yield. However, one of the many methods for raising yield that is yet to be fully investigated is increasing the number of spikelets by minimising spikelet abortion. Spikelet abortion dramatically increases during the late reproductive phase, but the molecular and genetic mechanisms remain unknown. Here, we employed a phenotyping approach in which developed and undeveloped spikelets were detected and counted during spike development and their maximum yield potential (MYP) was investigated. We studied 20 agronomic and spikelet‐related traits using a set of 184 diverse spring barley accessions under field conditions. By employing a set of >125K  SNPs, GWAS was conducted. Our analysis revealed 26 genetic clusters associated with MYP and the number of developed and undeveloped spikelets. Most of the significant associated genomic regions were co‐located near the candidate genes of phytohormones such as ABA, auxin, and cytokinin suggesting the importance of phytohormones in keeping spikelets alive, their development, and MYP. Our findings point to a potential link between jasmonic acid and the MYP, development and abortion of spikelets. We further provide genetic evidence that sugar‐related genes and sucrose have the potential to regulate MYP, spikelet development and spikelet survival. Our findings can be used for marker‐assisted breeding and as a resource for future molecular and genetic validation. Collectively, we propose a new genetic network linking spikelet‐related traits to grain yield determinants

A cosmological model in Weyl-Cartan spacetime

We present a cosmological model for early stages of the universe on the basis of a Weyl-Cartan spacetime. In this model, torsion $T^{\alpha}$ and nonmetricity $Q_{\alpha \beta}$ are proportional to the vacuum polarization. Extending earlier work of one of us (RT), we discuss the behavior of the cosmic scale factor and the Weyl 1-form in detail. We show how our model fits into the more general framework of metric-affine gravity (MAG).Comment: 19 pages, 5 figures, typos corrected, uses IOP style fil

Conformally invariant wave-equations and massless fields in de Sitter spacetime

Conformally invariant wave equations in de Sitter space, for scalar and vector fields, are introduced in the present paper. Solutions of their wave equations and the related two-point functions, in the ambient space notation, have been calculated. The ``Hilbert'' space structure and the field operator, in terms of coordinate independent de Sitter plane waves, have been defined. The construction of the paper is based on the analyticity in the complexified pseudo-Riemanian manifold, presented first by Bros et al.. Minkowskian limits of these functions are analyzed. The relation between the ambient space notation and the intrinsic coordinates is then studied in the final stage.Comment: 21 pages, LaTeX, some details adde

Complex Systems Science: Dreams of Universality, Reality of Interdisciplinarity

Using a large database (~ 215 000 records) of relevant articles, we empirically study the "complex systems" field and its claims to find universal principles applying to systems in general. The study of references shared by the papers allows us to obtain a global point of view on the structure of this highly interdisciplinary field. We show that its overall coherence does not arise from a universal theory but instead from computational techniques and fruitful adaptations of the idea of self-organization to specific systems. We also find that communication between different disciplines goes through specific "trading zones", ie sub-communities that create an interface around specific tools (a DNA microchip) or concepts (a network).Comment: Journal of the American Society for Information Science and Technology (2012) 10.1002/asi.2264

GWAS: Fast-forwarding gene identification and characterization in temperate Cereals: lessons from Barley – A review

Understanding the genetic complexity of traits is an important objective of small grain temperate cereals yield and adaptation improvements. Bi-parental quantitative trait loci (QTL) linkage mapping is a pow- erful method to identify genetic regions that co-segregate in the trait of interest within the research pop- ulation. However, recently, association or linkage disequilibrium (LD) mapping using a genome-wide association study (GWAS) became an approach for unraveling the molecular genetic basis underlying the natural phenotypic variation. Many causative allele(s)/loci have been identified using the power of this approach which had not been detected in QTL mapping populations. In barley (Hordeum vulgare L.), GWAS has been successfully applied to define the causative allele(s)/loci which can be used in the breeding crop for adaptation and yield improvement. This promising approach represents a tremendous step forward in genetic analysis and undoubtedly proved it is a valuable tool in the identification of can- didate genes. In this review, we describe the recently used approach for genetic analyses (linkage map- ping or association mapping), and then provide the basic genetic and statistical concepts of GWAS, and subsequently highlight the genetic discoveries using GWAS. The review explained how the candidate gene(s) can be detected using state-of-art bioinformatic tools