Search results for "VARIATION"
showing 10 items of 2124 documents
Data Evaluation in Population Genetics and Evolution
1994
Isozymes maybe generated by different enzyme loci (a) (isoenzymes), (b) alleles of a locus (allozymes) or (c) post-translational modifications (secondary isozymes). Differences in isozyme numbers and isoenzyme properties can be used for evolutionary studies. But quantitations of genetic variation among or within populations are obtainable only from allozyme frequencies.
Investigations on the geographical variability of the human transferrins.
1971
On the basis of own and from the widely scattered literature compiled materials the geographical distribution of the transferrin alleles is discussed. They reveal a characteristic distribution pattern, as the slow Tf variants produced by TfD alleles are obviously more frequent in tropical than in non-tropical populations. Considering similar results in cattle and its interpretation by Ashton (1958, 1965), it is hypothesized, that the relatively high TfΓ frequencies in tropical biotops might be a selective adaptation to their special climatic conditions. In this connection an association between slowly moving transferrin proteins in man and tolerance to hotter climates — as could be found in…
Connectivity defects enhance chain dynamics in supramolecular polymer model-network gels
2016
Supramolecular polymer networks exhibit twofold dynamics: that of their polymer chains and that of the transient bonds between them, which is further complexed when irregular network structures lead to local variation of both. A typical irregularity is imperfect network-chain connectivity. To assess the impact of that, we study the diffusion of three different types of tracer polymers in supramolecular model networks of four-arm star-shaped poly(ethylene glycol). First, we focus on tracers that carry three stickers and one fluorescent label at their four arms, thereby creating an inherent network connectivity defect in their vicinity. Second, we embed tracers that carry four stickers and fo…
The quality of Valle del Belice sheep’s milk and cheese produced in the hot summer season in Sicily
2013
In response to the growing consumer demand for fresh cheese in summer, this investigation was aimed to evaluate the chemical and microbiological characteristics of sheep’s milk and cheese produced in Sicily in the hot summer months. A total of 810 bulk milk samples collected from 17 farms rearing ewes of the Valle del Belice breed were analysed for chemical composition, somatic cell count, total bacterial count and clotting parameters. Samples (n = 18) of Protected Designation of Origin Vastedda della valle del Belice cheese produced in six dairies were collected in summer, autumn and spring and analysed for chemical composition, microbiological profile and fatty acid (FA) composition. Univ…
Studies on the diurnal courses of the contents of abscisic acid, 1-aminocyclopropane carboxylic acid and its malonyl conjugate in needles of damaged …
1993
Summary The diurnal courses of the contents of 1-aminocyclopropane carboxylic acid (ACC), its malonyl conjugate (MACC) and abscisic acid (ABA) in the two-year-old needles of damaged and undamaged spruce trees (Picea abies L.) were investigated. The contents of ACC and MACC were significantly higher in the needles of the damaged trees as compared with the undamaged ones. In the needles of the damaged spruce trees, the ACC and MACC contents, and ABA contents as well, fluctuated to a greater extent than those in the undamaged spruce trees during the day. The relationships between ACC-ABA and MACC-ACC contents as well are also discussed.
Regulatory Changes in Pterin and Carotenoid Genes Underlie Balanced Color Polymorphisms in the Wall Lizard
2018
ABSTRACTReptiles use pterin and carotenoid pigments to produce yellow, orange, and red colors. These conspicuous colors serve a diversity of signaling functions, but their molecular basis remains unresolved. Here, we show that the genomes of sympatric color morphs of the European common wall lizard, which differ in orange and yellow pigmentation and in their ecology and behavior, are virtually undifferentiated. Genetic differences are restricted to two small regulatory regions, near genes associated with pterin (SPR) and carotenoid metabolism (BCO2), demonstrating that a core gene in the housekeeping pathway of pterin biosynthesis has been co-opted for bright coloration in reptiles and indi…
Effect of konjac glucomannan addition on aroma release in gels containing potato starch.
2014
International audience; The present study aimed to measure the retention of aroma compounds (ethyl acetate, ethyl hexanoate and carvacrol) in dispersions based on konjac glucomannan and/or potato starch, and to highlight the influence of konjac glucomannan on the mechanisms involved in aroma retention. Publications on the effect of konjac glucomannan on aroma release are scarce. Konjac glocomannan is a polysaccharide used as a food additive for its viscous and emulsifying properties. Retention of aroma compounds in dispersions was calculated from partition coefficients which were measured using the phase ratio variation method. This method, consisting of analyses of the headspace at equilib…
Genome-wide detection of copy-number variations in local cattle breeds
2019
The aim of the present study was to identify copy-number variations (CNVs) in Cinisara (CIN) and Modicana (MOD) cattle breeds on the basis of signal intensity (logR ratio) and B allele frequency of each marker, using Illumina’s BovineSNP50K Genotyping BeadChip. The CNVs were detected with the PennCNV and SVS 8.7.0 software and were aggregated into CNV regions (CNVRs). PennCNV identified 487 CNVs in CIN that aggregated into 86 CNVRs, and 424 CNVs in MOD that aggregated into 81 CNVRs. SVS identified a total of 207 CNVs in CIN that aggregated into 39 CNVRs, and 181 CNVs in MOD that aggregated into 41 CNVRs. The CNVRs identified with the two softwares contained 29 common CNVRs in CIN and 17 co…
Multiscale variation in drought controlled historical forest fire activity in the boreal forests of eastern Fennoscandia
2017
Forest fires are a key disturbance in boreal forests, and characteristics of fire regimes are among the most important factors explaining the variation in forest structure and species composition. The occurrence of fire is connected with climate, but earlier, mostly local-scale studies in the northern European boreal forests have provided little insight into fire-climate relationship before the modern fire suppression period. Here, we compiled annually resolved fire history, temperature, and precipitation reconstructions from eastern Fennoscandia from the mid-16th century to the end of the 19th century, a period of strong human influence on fires. We used synchrony of fires over the network…
Serological and molecular characteristics of Vibrio vulnificus biotype 3: evidence for high clonality.
2007
Vibrio vulnificus biotype 3 has been implicated as the causative pathogen of an ongoing disease outbreak that erupted in Israel in 1996. Recent work based on multi-locus sequence typing (MLST) showed that V. vulnificus biotype 3 is genetically homogeneous. The aim of this study was to investigate the existence of subpopulations within this homogeneous biotype by characterizing the surface antigens and analysing the sequence diversity of selected outer-membrane protein (OMP)-encoding genes. Rabbit antisera were prepared against biotype 1, 2 and 3 strains. The results of the slide-agglutination test, dot-blot assay (using fresh and boiled cells), and immunoblotting of lipopolysaccharides (LPS…