Search results for "polymorph"
showing 10 items of 2115 documents
Crossed 2D versus Slipped 1D π-Stacking in Polymorphs of Crystalline Organic Thin Films
2019
Polymorphs of organic semiconductors are of great interest as they shed light to structure-property relationships. The full X-ray thin film structure analysis of two polymorphs (B, G) of an important n-type semiconducting dicyano-distyrylbenzene based small molecule (CN-TFPA) is reported. Drastically different structures of the monotropic phases are revealed, that is an uncommon 2D crossed π-stacked arrangement for the B-phase versus a 1D slipped π-stack for G. Both phases exhibit a layered structure in the (100) plane with high structural integrity, driven by the hydrophobic contacts of the terminal CF3 groups; as (100) coincides with the film surface, this allows for exfoliation by scotch…
A genome-wide association study of marginal zone lymphoma shows association to the HLA region
2015
Marginal zone lymphoma (MZL) is the third most common subtype of B-cell non-Hodgkin lymphoma. Here we perform a two-stage GWAS of 1,281 MZL cases and 7,127 controls of European ancestry and identify two independent loci near BTNL2 (rs9461741, P=3.95 × 10−15) and HLA-B (rs2922994, P=2.43 × 10−9) in the HLA region significantly associated with MZL risk. This is the first evidence that genetic variation in the major histocompatibility complex influences MZL susceptibility.
Further investigations on populations of the deep-water blue and red shrimp Aristeus antennatus (Risso, 1816) (Decapoda, Dendrobranchiata), as inferr…
2012
The aim of this study was to integrate existing mitochondrial DNA data relating to the deep-sea blue and red shrimp Aristeus antennatus (Risso, 1816) with data obtained by Amplified Fragment Length Polymorphism (AFLP). A total of 145 AFLP polymorphic loci were scored in 236 specimens collected from one Atlantic and seven Mediterranean sample sites. AMOVA results revealed that the overall genetic variation among-populations was lower (11.81%) than within-populations (88.19%). The genetic variation between the Atlantic and Mediterranean samples was found to be not significant ( Φ CT = − 0 . 007 ; N.S.), indicating that the transition area between the Atlantic Ocean and the Mediterranean Sea d…
The 1258 GA polymorphism in the neuropeptide Y gene is associated with greater alcohol consumption in a Mediterranean population.
2011
Abstract Neuropeptide Y (NPY) is a neurotransmitter widely distributed in the central nervous system. Several studies have demonstrated that increases of NPY are associated with reduced alcohol intake and anxiety manifestations. The Leu7Pro polymorphism in the NPY has been associated with alcohol consumption, but evidence is scarce. In the Spanish Mediterranean population, this variant is not polymorphic. Thus, our aim is to identify novel functional variants in the NPY and to investigate the impact of these markers and others previously described on alcohol consumption in this population. A total of 911 subjects (321 men and 590 women) from the Spanish Mediterranean population were recruit…
Testing Taxonomic and Biogeographical Relationships in a Narrow Mediterranean Endemic Complex (Hippocrepis balearica) using RAPD Markers
2002
Analyses of RAPD profiles from 17 populations of the Hippocrepis balearica complex revealed a highly structured geographic pattern, not only among continental–insular areas but also within the eastern Balearic islands. In marked contrast to previous morphometric results, a clear separation between continental and insular samples was found, and intermediates between H. balearica and H. valentina samples were not detected. Molecular data indicated that western and eastern Balearic populations of the complex (H. grosii and H. balearica) were more closely related to each other than to continental populations (H. valentina). Multivariate analyses of the RAPD data clearly indicated that the simil…
Historical biogeography in a linear system: genetic variation of Sea Rocket (Cakile maritima) and Sea Holly (Eryngium maritimum) along European coasts
2000
The exclusively coastal Cakile maritima and Eryngium maritimum represent a linear biogeographical system. Genetic variation among 25 individuals of C. maritima and 16 individuals of E. maritimum, from the coasts of Europe, North Africa and the Canary Islands, was analysed using random amplified polymorphic DNAs (RAPDs) and intersimple sequence repeats (ISSRs). Genetic distances (Dice) were calculated and used to investigate the correlation between genetic and geographical distances, to construct Neighbour Joining (NJ) trees, and to compare mean genetic distances between areas within and across species. Genetic distances and geographical distances measured along the coast are well correlated…
Variation in pheno-morphological and agronomic traits among burr medic (Medicago polymorpha L.) populations collected in Sicily, Italy
2010
The present study assessed the diversity of pheno-morphological and agronomic traits among 31 natural populations of burr medic (Medicago polymorpha L.) from different environments throughout Sicily, and analysed the patterns of phenotypic diversity in relation to the environmental parameters of each collection site. Three commercial cultivars (Cavalier, Santiago, and Anglona) were also included in the study as check cultivars. Two field experiments were performed in 2005–06 in a hilly area of the Sicilian inland. Principal components analysis (PCA) was performed on the sites using geographic, climatic, and pedological data to assess the differences in types of collection sites. PCA was al…
Education modulates the association of the FTO rs9939609 polymorphism with body mass index and obesity risk in the Mediterranean population
2012
Objective To define whether the rs9939609 FTO (fat mass and obesity associated) single nucleotide polymorphism (SNP) is associated with anthropometric measurements and its modulation by educational level in a Mediterranean population. Methods We studied 3 independent adult samples: a random sample (n = 1580) from the general population (GP), obese hospital patients (OHP) (n = 203) and elderly subjects (n = 1027) with high cardiovascular risk (HCR). Weight and height were directly measured. Education and physical activity (PA) were measured using questionnaires. Results The rs9939609 presented heterogeneous associations with BMI. In the GP, the minor A-allele was significantly associated wit…
Chromosomal location polymorphism of major rDNA sites in two Mediterranean populations of the killifih Aphanius fasciatus (Pisces: Cyprinodontidae)
2005
The chromosomes of the Mediterranean killifish, Aphanius fasciatus from two populations, the Lagoon of Venice (LV, 15 specimens) and the Lagoon ‘Stagnone di Marsala’ (Sicily) (SM, 48 specimens), have been investigated using conventional Ag-staining and fluorescent in situ hybridization (FISH) with 18S rDNA probe. The two methods revealed variation in the number of major rDNA sites ranging from 8 to 14 (LV) and from 1 to 4 (SM) per individual. The fact that each individual possessed its own number of sites implies that observed variation was structural. Moreover, overlapping of silver staining and FISH patterns demonstrated that all ribosomal genes were transcriptionally active in each speci…
Genetic Structure of Wild and Cultivated Olives in the Central Mediterranean Basin
2006
Background and Aims: Olive cultivars and their wild relatives (oleasters) represent two botanical varieties of Olea europaea subsp. europaea (respectively europaea and sylvestris). Olive cultivars have undergone human selection and their area of diffusion overlaps that of oleasters. Populations of genuine wild olives seem restricted to isolated areas of Mediterranean forests, while most other wild-looking forms of olive may include feral forms that escaped cultivation. Methods: The genetic structure of wild and cultivated olive tree populations was evaluated by amplified fragment length polymorphism (AFLP) markers at a microscale level in one continental and two insular Italian regions. Key…