Singularities of affine equidistants: projections and contacts

Using standard methods for studying singularities of projections and of contacts, we classify the stable singularities of affine $\lambda$-equidistants of $n$-dimensional closed submanifolds of $\mathbb R^q$, for $q\leq 2n$, whenever $(2n,q)$ is a pair of nice dimensions.Comment: 18 pages, v2 (minimal changes) agrees with version to appear in Journal of Singularitie

Reproductive isolation in the Aegean Ophrys omegaifera complex (Orchidaceae)

The orchid genus Ophrys operates a system of sexual deception by which high specificity of pollination is attained. Reproductive isolation in Ophrys mainly rests upon prezygotic isolation mechanisms. The level of genetic separateness of Ophrys taxa with different pollinators is therefore likely determined by the fidelity of pollinators. The present study employs genetic fingerprinting to investigate this in the east Aegean Ophrys omegaifera s.l. complex, also including O. dryis, a west Mediterranean species of this complex. Ophrys fleischmannii, O. basilissa, and the west Mediterranean O. dyris, are found to be well-separated genetic entities whereas O. omegaifera s.str. and the putative hybrid taxon, O. sitiaca, are found to be genetically inseparable across their entire range of co-occurrence. This suggests that specific pollinators have high enough fidelity to act as effective isolating factors in east Aegean O. omegaifera s.l. as a whole, but that the situation in the species pair of O. sitiaca and O. omegaifera is likely to be more comple

Genetic variability in Brazilian Capsicum baccatum germplasm collection assessed by morphological fruit traits and AFLP markers.

<div><p><i>Capsicum baccatum</i> is one of the main pepper species grown and consumed in South America. In Brazil, it is commonly cultivated by family farmers, using mostly the genotypes bishop's hat genotypes (locally <i>cambuci</i>) and red chili pepper (<i>dedo-de-moça</i>). This study had the objective of characterizing 116 <i>C</i>. <i>baccatum</i> accessions from different regions of Brazil, based on morphological fruit descriptors and AFLP (Amplified Fragment Length Polymorphisms) markers. Broad phenotypic variability among the <i>C</i>. <i>baccatum</i> accessions was detected when using morphological fruit descriptors. The Ward modified location model (Ward-MLM) discriminated five groups, based mainly on fruit shape. Six combinations of AFLP primers detected polymorphism in 97.93% of the 2466 identified bands, indicating the high genetic variability in the accessions. The UPGMA coincided with the Bayesian clustering analysis and three large groups were formed, separating the wild variety <i>C</i>. <i>baccatum</i> var. <i>praetermissum</i> from the other accessions. There was no relation between genetic distance and geographical origin of the accessions, probably due to the intense exchange of fruits and seeds between farmers. Morphological descriptors used together with AFLP markers proved efficient in detecting the levels of genetic variability among the accessions maintained in the germplasm collections. These results can be used as an additional source of helpful information to be exploited in <i>C</i>. <i>baccatum</i> breeding programs.</p></div

An 11th century a.d. burnt granary at La Gravette, south-western France : preliminary archaeobotanical results

International audienceA thick layer of carbonised seeds was encountered in an 11th century a.d. room situated in the seigneurial part of the village of La Gravette. This paper presents the first results of charcoal and seed analyses which give information on the food products stored in the granary and on their arrangement there. Triticum aestivum/durum/turgidum was by far the most important stored crop, while Avena sp., then Hordeum vulgare, Secale cereale, Triticum monococcum and Vitis vinifera were secondary. Weeds were poorly represented. Charcoals were dominated by deciduous Quercus sp., and 11 additional wood taxa were recorded, including especially Fagus sylvatica, Fraxinus sp., Rosaceae, Corylus avellana, Acer campestre and Ulmus sp. According to the charcoal distribution, Quercus and Fagus were probably building materials while most of other taxa would have been used for basketry, wattling or joinery work. In the western part of the granary, naked wheat was stored in bulk. In the eastern part, various crops (at least naked wheat, barley, rye, oat and grape) were stored in small amounts, most of which were probably separated by light wooden structures. The cereal crops had largely been processed and cleaned. The stored products probably represent taxes paid to the lord who owned the granary

Complete Genome Sequence of Bifidobacterium longum W11 (LMG P-21586), Used as a Probiotic Strain

We report the complete genome sequence of Bifidobacterium longum W11 (LMG P-21586) isolated from the intestinal microbiota of a healthy man. The analysis of the sequence may provide insights into the microbiological characteristics and the functional activity of this probiotic strain

Genetic diversity among forty coffee varieties assessed by RAPD markers associated with restriction digestion

The genetic variability of 40 accessions of_C. arabica was evaluated using a combination of the random amplified polymorphic DNA (RAPD) technique and restriction digestion of genomic DNA. The genetic variability and the relatedness among all accessions were initially evaluated using 195 RAPD primers which revealed a very low level of genetic variation. To improve the efficiency in the detection of polymorphism, the genomic DNA of all accessions were submitted to digestion with restriction endonucleases prior to PCR amplification. A total of 24 primers combined with restriction digestion of DNA rendered 318 bands, of which 266 (83.65%) were polymorphic. The associations among genotypes were estimated using UPGMA-clustering analysis. The accessions were properly clustered according to pedigree and agronomic features. The ability to distinguish among coffee accessions was greater for RAPD plus restriction digestion than for RAPD alone, providing evidences that the combination of the techniques was very efficient for the estimation of genetic relationship among_C. arabica genotypes.Leandro Eugênio Cardamoni Diniz, Claudete de Fátima Ruas, Valdemar de Paula Carvalho, Fabrício Medeiros Torres, Eduardo Augusto Ruas, Melissa de Oliveira Santos, Tumoru Sera and Paulo Maurício Rua

Impact of Extreme Obesity and Diet-Induced Weight Loss on the Fecal Metabolome and Gut Microbiota

Scope: A limited number of human studies have characterized fecal microbiota and metabolome in extreme obesity and after diet-induced weight loss. Methods and results: Fecal samples from normal-weight and extremely obese adults and from obese participants before and after moderate diet-induced weight loss are evaluated for their interaction with the intestinal adenocarcinoma cell line HT29 using an impedance-based in vitro model, which reveals variations in the interaction between the gut microbiota and host linked to obesity status. Microbiota composition, short chain fatty acids, and other intestinal metabolites are further analyzed to assess the interplay among diet, gut microbiota, and host in extreme obesity. Microbiota profiles are distinct between normal-weight and obese participants and are accompanied by fecal signatures in the metabolism of biliary compounds and catecholamines. Moderate diet-induced weight loss promotes shifts in the gut microbiota, and the primary fecal metabolomics features are associated with diet and the gut–liver and gut–brain axes. Conclusions: Analyses of the fecal microbiota and metabolome enable assessment of the impact of diet on gut microbiota composition and activity, supporting the potential use of certain fecal metabolites or members of the gut microbiota as biomarkers for the efficacy of weight loss in extreme obesity

In vitro evaluation of different prebiotics on the modulation of gut microbiota composition and function in morbid obese and normal-weight subjects

The gut microbiota remains relatively stable during adulthood; however, certain intrinsic and environmental factors can lead to microbiota dysbiosis. Its restoration towards a healthy condition using best-suited prebiotics requires previous development of in vitro models for evaluating their functionality. Herein, we carried out fecal cultures with microbiota from healthy normal-weight and morbid obese adults. Cultures were supplemented with different inulin-type fructans (1-kestose, Actilight, P95, Synergy1 and Inulin) and a galactooligosaccharide. Their impact on the gut microbiota was assessed by monitoring gas production and evaluating changes in the microbiota composition (qPCR and 16S rRNA gene profiling) and metabolic activity (gas chromatography). Additionally, the effect on the bifidobacterial species was assessed (ITS-sequencing). Moreover, the functionality of the microbiota before and after prebiotic-modulation was determined in an in vitro model of interaction with an intestinal cell line. In general, 1-kestose was the compound showing the largest effects. The modulation with prebiotics led to significant increases in the Bacteroides group and Faecalibacterium in obese subjects, whereas in normal-weight individuals, substantial rises in Bifidobacterium and Faecalibacterium were appreciated. Notably, the results obtained showed differences in the responses among the tested compounds but also among the studied human populations, indicating the need for developing population-specific products

Neuronal cholesterol metabolism increases dendritic outgrowth and synaptic markers via a concerted action of GGTase-I and Trk

We are deeply thankful to Professor David W. Russell (University of Texas Southwestern Medical Center) for the kind gift of the anti-CYP46A1 antibody. This work was supported by FEDER (COMPETE Programme) and national funds from Fundacao para a Ciencia e a Tecnologia (FCT), Portugal, research grants iMed.ULisboa (UID/DTP/04138/2013), PTDC/SAU/NMC/110809/2009 (to E.R.), SFRH/BD/78041/2011 (to M.M.) SFRH/BPD/95855/2013 (to M.J.N), and, Swedish Research Council (J.L.R. and I.B.), Marie Curie Career Integration Grant and Novo Nordisk Fonden (J.L.R.) and Swedish Brain Power (I.B.).Cholesterol 24-hydroxylase (CYP46A1) is responsible for brain cholesterol elimination and therefore plays a crucial role in the control of brain cholesterol homeostasis. Altered CYP46A1 expression has been associated with several neurodegenerative diseases and changes in cognition. Since CYP46A1 activates small guanosine triphosphate-binding proteins (sGTPases), we hypothesized that CYP46A1 might be affecting neuronal development and function by activating tropomyosin-related kinase (Trk) receptors and promoting geranylgeranyl transferase-I (GGTase-I) prenylation activity. Our results show that CYP46A1 triggers an increase in neuronal dendritic outgrowth and dendritic protrusion density, and elicits an increase of synaptic proteins in the crude synaptosomal fraction. Strikingly, all of these effects are abolished by pharmacological inhibition of GGTase-I activity. Furthermore, CYP46A1 increases Trk phosphorylation, its interaction with GGTase-I, and the activity of GGTase-I, which is crucial for the enhanced dendritic outgrowth. Cholesterol supplementation studies indicate that cholesterol reduction by CYP46A1 is the necessary trigger for these effects. These results were confirmed in vivo, with a significant increase of p-Trk, pre- and postsynaptic proteins, Rac1, and decreased cholesterol levels, in crude synaptosomal fractions prepared from CYP46A1 transgenic mouse cortex. This work describes the molecular mechanisms by which neuronal cholesterol metabolism effectively modulates neuronal outgrowth and synaptic markers.publishersversionpublishe