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Carbonyl{3,3′-di-tert-butyl-5,5′-dimethoxy-2,2′-bis[(4,4, 5,5-tetramethyl-1,3,2-dioxaphospholan-2-yl)oxy]biphenyl-κ2 P,P′}hydrido(triphenylphosphane-κP)rhodium(I) diethyl ether trisolvate
In the title compound, [RhH(C74H68O8P2)(C18H15P)(CO)]·3C4H10O, the CHP3 coordination set at the RhI ion is arranged in a distorted trigonal-bipyramidal geometry with the P atoms adopting equatorial coordination sites and the C atom of the carbonyl ligand as well as the H atom adopting the axial sites. The asymmetric unit contains two very similar molecules of the rhodium complex, two half-occupied diethyl ether molecules and further diethyl ether solvent molecules which could not be modelled successfully. Therefore contributions of the latter were removed from the diffraction data using the SQUEEZE procedure in PLATON [Spek (2009). Acta Cryst. D65, 148-155]
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
Genetic control of biosynthesis of soluble isoforms of lipoxygenase in bread wheat grain
Trabalho final de mestrado integrado em Medicina, apresentado à Faculdade de Medicina da Universidade de Coimbra.A dermatite seborreica é uma dermatose inflamatória comum, com picos de incidência na infância e na idade adulta. A sua etiologia permanece desconhecida. No adulto, pensa-se que esta será uma doença multifatorial em que fungos Malassezia spp., alterações da imunidade celular e uma eventual predisposição genética desempenham papéis importantes. Na criança, é também sobre os fungos do Malassezia spp. que recaem as principais suspeitas.
É muito debatido se a dermatite seborreica infantil existe efetivamente. A revisão da literatura revela três opiniões principais. Alguns autores negam a sua existência considerando-a uma forma de apresentação de outras patologias. Outros autores admitem que esta exista mas chamam a atenção para uma relação entre dermatite seborreica na infância e manifestações atópicas no futuro. Um terceiro grupo sugere que esta não seja uma doença mas antes uma sÃndrome, abrangendo sinais comuns à forma precoce de várias doenças.
No que diz respeito à relação entre dermatite seborreica da criança e do adulto, a literatura é escassa. Atualmente não existe evidência sugestiva de que crianças com a doença possuam maior probabilidade de a desenvolver na idade adulta e parece não existir relação entre as variantes do adulto e da criança, apesar de possÃveis semelhanças etiopatogénicas.
O presente artigo faz uma revisão da literatura existente acerca de dermatite seborreica no adulto e na criança, com especial destaque para a etiopatogenia e para a posição nosológica na criança. Foi realizada pesquisa bibliográfica nas fontes médicas Pubmed/Medline e b-on, considerando preferencialmente artigos publicados a partir do ano 2000 mas recorrendo a fontes mais antigas se possuindo interesse histórico para o tema.Seborrheic dermatitis is a common inflammatory disease that affects both adults and children. The exact cause is yet to be identified. In adults, the disease is probably multifactorial, related with Malassezia yeasts, altered cell-mediated immunity and a possible genetic predisposition. In infants, Malassezia spp. yeasts are also the most studied etiology.
It is highly debated whether infantile seborrheic dermatitis truly exists. Reviewing the literature on the subject, it is possible to identify three main opinions. Some authors deny its existence, considering it to be a clinical variant that precedes the development of other conditions. Other authors believe in its existence but emphasize the strong correlation between having seborrheic dermatitis in childhood and future atopic manifestations. A third group of authors suggests infantile seborrheic dermatitis is better described as a syndrome rather that a disease, because it combines signs that are common to the early stages of many conditions.
When it comes to the association between adult and infantile seborrheic dermatitis, literature is scarce. There is no evidence to suggest that infants with seborrheic dermatitis have a higher probability of having the disease as adults and it is unlikely that adult seborrheic dermatitis has any relationship to the childhood variant despite possible etiopathogenic similarities.
This work presents a review of the literature available on infantile and adult seborrheic dermatitis, emphasizing etiopathogenesis and the nosological position in infants. A bibliographical research based on the medical sources Pubmed/Medline and b-on was conducted, giving preference to articles published since the year of 2000. Older literature was considered when having historical interest to the theme
Variability of alkaloid content in Papaver somniferum L.
A total of 300 accessions of opium poppy (Papaver somniferum L., Papaveraceae) of the IPK genebank collection from nearly all over the world were cultivated under field conditions in Gatersleben for morphological and phytochemical characterisation. Altogether 35 morphological and agronomic characters were collected for all accessions. Determination of chromosome numbers with flow cytometry showed that the accessions of subspecies setigerum are tetraploid whereas all accessions of the other subspecies are diploid. Composition and content of the five main alkaloids (morphine, codeine, thebaine, papaverine and noscapine) were analysed by high performance liquid chromatography (HPLC). Total alkaloid content varied between 683.32 and 25,034.84 μg/g dry matter (first year) and 1,799.49 and 25,338.55 μg/g dry matter in the second year of cultivation. There is a highly significant correlation between total content of alkaloids and morphine in both years (r=0.926/P=0.000; r=0.918/P=0.000). In contrast, the other four main alkaloids show less or no correlation with each other or the total alkaloid content. This analysis demonstrated that the amount and composition of the main alkaloids are highly variable. Additionally, there is no important correlation between morphological characters and alkaloid content. So it is not possible to use these characters as a prediction tool of alkaloid content during breeding process
Climate variability, forcings, feedbacks and responses: The long-term perspective
The 8th International NCCR Climate Summer School was held in collaboration with PAGES and brought together 74 PhD and post-doctoral students from 16 different countries, mainly from Europe but also Japan, Australia, Chile, Russia, Canada and the USA, as well as18 keynote speakers and workshop leaders. The meeting was held in Grindelwald, a small alpine village located in the Jungfrau region of the Swiss Alps. Participants gathered together to learn about various aspects of paleoclimate science, including proxy reconstructions and modeling, to understand the nature of feedbacks, forcings and their impact on the climate system. The agenda of the meeting, included keynote lectures that were followed by lively discussions, poster sessions, workshops, excursions and group presentations by the participants
Uncovering the genetic architecture of spike related traits in bread wheat: a viable alternative to increase yield potential
Non-Peer ReviewedBased on the projected demand, further improvements in wheat grain yield are required. In this sense, exploring the genetic diversity associated with yield related traits is critical to derive superior progenies from crossing and selection. However, the possible presence of trade-off between traits must be considered to determine their relevance for improving yield potential. In this study, we determined the phenotypic and genetic relationships between twelve spike related traits and their genetic basis through an association mapping study using a 15K Infinium SNP array, characterized in a bread wheat panel. To identify potential candidate genes, regions of interest were positioned onto the newly released wheat reference genome sequence by blasting their peaking marker sequences against the IWGSC RefSeq v1.0. From all the analyzed traits, grain number per fertile spikelet (GFS) showed the highest correlation with grain number per spike (GNS), whereas there was no relationship with thousand kernel weight (TKW). As a result, significant increases in grain weight per spike (GWS) associated with higher GFS was observed. Interestingly, GFS was mostly explained by spikelet weight (SW), indicating that improvements in yield potential could be achieved through partition improving within the spike. In addition, the genetic analysis showed independent genetic control between GFS and both, GNS and TKW, suggesting the potential value of GFS as selection criterion to increase yield potential in wheat breeding programs. A total of 54 significant marker-trait associations were detected for spike related traits, including two genomic regions on 1B and 7A linked to GFS and 6 genomic regions located on 1A, 1B, 2B, 3A, 5A and 7B associated to SW. The potential candidate genes for these regions included several sugar transporter and carbohydrate-binding protein. The markers linked to GFS and SW are really promising, especially considering that due to the destructive phenotypic determination, their improvement in early breeding generations can only be made by marker-assisted selection
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
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 and
nonmetricity 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
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Crystal structure of (2,3-bis((2R,5R)-2,5-dimethylphosphonalyl)maleic anhydride)-(η4-norbornadiene)-rhodium(I) tetrafluoroborate, [Rh(C7H8)(C16H24O3P 2)] [BF4]
C23H32BF4O3P2Rh, orthorhombic, P212121 (no. 19), a = 10.147(2) Å, b = 13.246(3) Å, c = 18.827(4) Å, V = 2530.5 Å3, Z = 4, Rgt(F) = 0.025, wRref(F 2) = 0.067, T = 200 K. © by Oldenbourg Wissenschaftsverlag,
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