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The fluorescence kinetics in intact photosystem II (PS II) core particles from the cyanobacterium Thermosynechococcus elongatus is measured with picosecond resolution at room temperature in open reaction centers. The analysis of the overall trapping kinetics based on the theory of energy migration and trapping on lattices has shown that the charge separation kinetics in photosystem II is extremely trap-limited and not diffusion-to-the-trap limited.

Viola reichenbachiana (2 n = 4 x = 20) and V. riviniana (2 n = 8 x = 40) are closely related species widely distributed in Europe, often sharing the same habitat throughout their overlapping ranges. It has been suggested in numerous studies that their high intraspecific morphological variability and plasticity might have been further increased by interspecific hybridisation in contact zones, given the sympatry of the species and the incomplete sterility of their hybrid. The aims of this study were to: (i) confirm that V. reichenbachiana and V. riviniana have one 4 x genome in common, and (ii) determine the impact of hybridisation and introgression on genetic variation of these two species in selected European populations., For our study, we used 31 Viola populations from four European countries, which were analysed using AFLP and sequencing of a variable plastid intergenic spacer, trnH-psbA., Our analysis revealed that V. reichenbachiana exhibited larger haplotype diversity, having three species-specific haplotypes versus one in V. riviniana. The relationships among haplotypes suggest transfer of common haplotypes into V. riviniana from both V. reichenbachiana and hypothetically the other, now extinct, parental species. AFLP analysis showed low overall genetic diversity of both species, with V. riviniana showing higher among-population diversity. None of the morphologically designated hybrid populations had additive AFLP polymorphisms that would have indicated recent hybridisation. Also, kinship coefficients between both species did not indicate gene flow. V. riviniana showed significant population subdivision and significant isolation by distance, in contrast to V. reichenbachiana., The results indicate lack of gene flow between species, high influence of selfing on genetic variability, as well as probably only localised introgression toward V. riviniana. [ABSTRACT FROM AUTHOR]

A comparison of the Fourier transform Raman spectrum and the infrared spectrum of thymine isolated in an argon matrix is presented.

Morphological characters, AFLP markers and flow cytometry were used to investigate the morphological and genetic variability and differentiation of Viola reichenbachiana and V. riviniana in non-metallicolous ( NM) and metallicolous (M) populations. The aims were to clarify the taxonomic status of plants occurring in ore-bearing areas, to determine any relationship in V. reichenbachiana and V. riviniana from sites not polluted with heavy metals, and to examine the genetic variability and differentiation of M and NM populations of both species. Multivariate analyses based on morphological characters showed significant differences between V. reichenbachiana and V. riviniana from non-polluted sites, high levels of intra- and inter-population variability, and the occurrence of inter-specific hybrids. Plants from M populations showed hybrid characters but also fell within the range of V. riviniana or V. reichenbachiana. There were no significant differences in relative genome size between plants from polluted areas and V. riviniana from NM populations. Bayesian analysis of population genetic structure based on AFLP markers distinguished two main groups: V. reichenbachiana and V. riviniana together with the M populations. That analysis also revealed the occurrence of populations of inter-specific hybrids from non-polluted areas. Further Bayesian analysis of V. riviniana including NM and M populations separated all the studied M populations from NM populations. We conclude that plants forming the M populations are well adapted to a metal-polluted environment, and could be considered as stabilised introgressive forms resulting from unidirectional (asymmetric) introgression toward V. riviniana. [ABSTRACT FROM AUTHOR]

To determine the relative importance of clonal growth and sexual reproduction, the Randomly Amplified Polymorphic DNA (RAPD) method was used to study genetic diversity and clonal structure of six populations of Elymus repens and four populations of Elymus hispidus from Poland. These outbreeding species are virtually self-sterile and form widely spreading and long-lived rhizomes. Using 12 primers, a total of 150 unambiguous RAPD fragments were amplified and scored. Results ofAMOVA showed no significant genetic distinction between morphologically distinguished varieties of E. repens and E. hispidus. E. repens had slightly higher intra-specific genetic polymorphism than E. hispidus; the percentage of polymorphic bands per population ranged from 38 to 49 and from 19 to 38 respectively. Clonal diversity measured using the Simpson diversity index (D) indicated different contributions of clonal reproduction in particular populations of E. repens (D: 0.20–0.72). Populations of E. hispidus were dominated by one or a few clones, which were generally restricted to a single population (D: 0.00–0.22). RAPD revealed that most genetic diversity resided within populations of the two studied species, suggesting that, despite their clonal character, propagation by seeds contributes considerably to reproduction of E. repens and E. hispidus. [ABSTRACT FROM AUTHOR]

Over 3% of the entire Polish population migrate for a job within the European Union, most are aged 18-44 years. The main destinations are Germany, the United Kingdom and Ireland. Immigration is connected with the use of many public services, including healthcare services. Assuming Polish immigrants require medical consultations in the countries they reside in, the authors have analysed the reasons for patients' visits to general practitioners (GPs) in Poland in order to predict possible reasons why Polish patients living abroad may make appointments with GPs in other countries. Data from 22 769 visits to GP practices between June 2005 and May 2006 by Polish patients aged 18-44 years were collected electronically. Age was categorised into three groups (18-24, 25-34 and 35-44 years) and the reason for the visit was categorised according to the ICD 10 coding system. Among the 12 535 patients registered with GPs, 73.1% of women and 68.6% of men required consultations during the year the study was conducted. The highest percentage of visits was recorded for women aged 35-44 years, while men of the same age were the least likely to visit a GP. The mean number of visits per patient ranged from 1.89 for men aged 25-34 years to 3.11 for women aged 35-44 years. The means were similar for 18- to 24-year-old men and women. Women aged 35-44 years had a higher mean number of visits compared with women aged 18-24 years, whereas the opposite was true for men. The analysis of reasons for visits within the age groups indicated that the percentage of appointments for respiratory problems and general and unspecified problems dropped by more than half from the 18-24-year-olds to the 35-44-years-olds, while visits for musculosceletal, cardiovascular, and mental and behavioural problems increased by a factor of four. The presented results intend to enable healthcare services meet Polish immigrants' healthcare needs. [ABSTRACT FROM AUTHOR]