9 research outputs found
Diffeomorphism Invariant Actions for Partial Systems
Local action principles on a manifold \M are invariant (if at all) only
under diffeomorphisms that preserve the boundary of \M. Suppose, however,
that we wish to study only part of a system described by such a principle;
namely, the part that lies in a bounded region of spacetime where is
specified in some diffeomorphism invariant manner. In this case, a description
of the physics within should be invariant under {\it all} diffeomorphisms
regardless of whether they preserve the boundary of this region. The following
letter shows that physics in such a region can be described by an action
principle that ) is invariant under both diffeomorphisms which preserve the
boundary of and those that do not, ) leaves the dynamics of the part of
the system {\it outside} the region completely undetermined, and ) can
be constructed without first solving the original equations of motion.Comment: 5 pages (10 preprint pages) ReVTe
Black Hole Solution of Quantum Gravity
We present a spherically symmetric and static exact solution of Quantum
Einstein Equations. This solution is asymptotically (for large ) identical
with the black hole solution on the anti--De Sitter background and, for some
range of values of the mass possesses two horizons. We investigate
thermodynamical properties of this solution.Comment: Plain Latex, 10 page
RNA-seq, de novo transcriptome assembly and flavonoid gene analysis in 13 wild and cultivated berry fruit species with high content of phenolics
This research was funded by the European Union Framework Program 7, Project BacHBerry [FP7–613793]. The authors also acknowledge support from the Institute Strategic Programmes ‘Designing Future Wheat’ (BB/P016855/1), ‘Understanding and Exploiting Plant and Microbial Secondary Metabolism’ (BB/J004596/1) and ‘Molecules from Nature’ (BB/P012523/1) from the UK Biotechnology and Biological Sciences Research Council to the John Innes Centre and the European funded COST ACTION FA1106 QualityFruit. VT, PV and CM have also received funding from the European Union’s Horizon 2020 research and innovation programme through the TomGEM project under grant agreement No. 679796. The funding bodies had no role in the design of the study, collection, analysis and interpretation of data nor in writing the manuscript.Background: Flavonoids are produced in all flowering plants in a wide range of tissues including in berry fruits. These compounds are of considerable interest for their biological activities, health benefits and potential pharmacological applications. However, transcriptomic and genomic resources for wild and cultivated berry fruit species are often limited, despite their value in underpinning the in-depth study of metabolic pathways, fruit ripening as well as in the identification of genotypes rich in bioactive compounds. Results: To access the genetic diversity of wild and cultivated berry fruit species that accumulate high levels of phenolic compounds in their fleshy berry(-like) fruits, we selected 13 species from Europe, South America and Asia representing eight genera, seven families and seven orders within three clades of the kingdom Plantae. RNA from either ripe fruits (ten species) or three ripening stages (two species) as well as leaf RNA (one species) were used to construct, assemble and analyse de novo transcriptomes. The transcriptome sequences are deposited in the BacHBerryGEN database (http://jicbio.nbi.ac.uk/berries) and were used, as a proof of concept, via its BLAST portal (http://jicbio.nbi.ac.uk/berries/blast.html) to identify candidate genes involved in the biosynthesis of phenylpropanoid compounds. Genes encoding regulatory proteins of the anthocyanin biosynthetic pathway (MYB and basic helix-loop-helix (bHLH) transcription factors and WD40 repeat proteins) were isolated using the transcriptomic resources of wild blackberry (Rubus genevieri) and cultivated red raspberry (Rubus idaeus cv. Prestige) and were shown to activate anthocyanin synthesis in Nicotiana benthamiana. Expression patterns of candidate flavonoid gene transcripts were also studied across three fruit developmental stages via the BacHBerryEXP gene expression browser (http://www.bachberryexp.com) in R. genevieri and R. idaeus cv. Prestige. Conclusions: We report a transcriptome resource that includes data for a wide range of berry(-like) fruit species that has been developed for gene identification and functional analysis to assist in berry fruit improvement. These resources will enable investigations of metabolic processes in berries beyond the phenylpropanoid biosynthetic pathway analysed in this study. The RNA-seq data will be useful for studies of berry fruit development and to select wild plant species useful for plant breeding purposes.publishersversionpublishe
Quantum Liouville theory and BTZ black hole entropy
In this paper I give an explicit conformal field theory description of
(2+1)-dimensional BTZ black hole entropy. In the boundary Liouville field
theory I investigate the reducible Verma modules in the elliptic sector, which
correspond to certain irreducible representations of the quantum algebra
U_q(sl_2) \odot U_{\hat{q}}(sl_2). I show that there are states that decouple
from these reducible Verma modules in a similar fashion to the decoupling of
null states in minimal models. Because ofthe nonstandard form of the Ward
identity for the two-point correlation functions in quantum Liouville field
theory, these decoupling states have positive-definite norms. The explicit
counting from these states gives the desired Bekenstein-Hawking entropy in the
semi-classical limit when q is a root of unity of odd order.Comment: LaTeX, 33 pages, 4 eps figure
Caracterização de genótipos de mirtilo utilizando marcadores moleculares Characterization of blueberry genotypes using molecular markers
O cultivo do mirtilo está em expansão no Brasil, em especial em regiões de clima temperado, onde há grande demanda em relação a cultivares adaptadas à s condições edafoclimáticas regionais. O objetivo deste trabalho foi caracterizar genótipos de mirtilo do programa de melhoramento da Embrapa Clima Temperado, utilizando marcadores moleculares do tipo RAPD e SSR. Foram caracterizados 40 genótipos de mirtilo por RAPD e oito cultivares por microssatélites. Os nove primers utilizados na técnica de RAPD geraram 89 marcadores. A similaridade genética entre os genótipos variou de 64 a 89%. Utilizando a similaridade média (66%), foram obtidos quatro grupos. Foram gerados 11 marcadores a partir de três pares de primers de microssatélites. A similaridade genética entre as cultivares variou de 25 a 75%. Com similaridade média (42,4%), foram obtidos três grupos. Com apenas três pares de primers de SSR, foi possÃvel definir o padrão das oito cultivares de mirtilo, revelando a eficiência da técnica de microssatélite na caracterização de genótipos dessa espécie. Esses resultados revelam a eficiência dos marcadores tipo RAPD e SSR na caracterização de genótipos de mirtilo. Entretanto, os marcadores tipo microssatélites geram resultados mais precisos, sendo os mais recomendados para uso em programas de melhoramento e identificação de cultivares.<br>The blueberry crop planting area is increasing in Brazil, especially in Temperate Climate Zones, generating demands relating to suitable cultivars adapted to regional climate and soil conditions. This work aimed to characterize blueberry genotypes from Embrapa Clima Temperado breeding program, using RAPD and SSR molecular markers. There were characterized 40 blueberry genotypes using RAPD and 8 cultivars using SSR molecular markers. The 9 RAPD primers generated 89 markers. The genetic similarity ranged from 64 to 89%. Through the average similarity (66%), it was possible to identify four groups. The three pairs of SSR primers generated 11 markers. The genetic similarity among cultivars ranged from 25 to 75%. With a similarity average of 42,4%, it was generated three groups. It was possible to define the pattern of the eight blueberry cultivars using only three pairs of SST primers, which shows the efficiency of SST technique when characterizing blueberry genotypes. These results reveal that both RAPD and SSR are efficient to characterize genotypes of this specie. However, SSR markers are more accurate and, therefore, recommended for use in breeding programs and cultivars identification
Cosmic evolution of supermassive black holes: A view into the next two decades
Discoveries over the past 20 years by Chandra and XMM-Newton surveys have significantly enhanced our view of supermassive black hole (SMBH) and galaxy evolution. We discuss new and exciting questions on the cosmic growth of SMBHs that can be addressed by new X-ray and multiwavelength observatories in the next two decades