Myrica cerifera L. (Myricaceae), the dominant woody species on many barrier islands along the southeastern coast of the United States, is expanding into grass-dominated, mesic, interdunal depressions where it forms dense thickets. Expansion may be attributed to a symbiotic nitrogen fixation with the bacterium Frankia, an evergreen leaf habit and, possibly, corticular photosynthesis (CP, i.e. refixation of respired CO2, %ref). We quantified seasonal variations in CP characteristics in first through fifth order branches of M. cerifera to determine the extent and relevance of CP to shrub expansion in coastal environments. Maximum mean %ref was 110±39 % of CO2 efflux in the dark (RD) in first order branches during winter. Minimum %ref was 18±3 % in fifth order branches during summer. Variations in %ref paralleled changes in incident photosynthetic photon flux density (PPFD). As incident PPFD attenuated with increasing branch order, %ref decreased. A less dense canopy in winter led to increased PPFD and increases in %ref. Total chlorophyll (Chl) content and Chl a/b ratios were consistent with shade acclimation as branch order increased. CP may be a mechanism to enhance M. cerifera shrub expansion because of the potential increase in whole plant carbon use efficiency and water use efficiency attributed to refixation of respired CO2. and J. K. Vick, D. R. Young.
As we can support with objective evidence, the position of men and women on the Czech labour market is not equal: (i) There is an obvious gender pay gap. (ii) Women are overrepresented in lower-paid professions with lower social prestige. Many authors (e.g. Čermáková, Crompton, Bradley) concerned with explanation of the reasons of the gender inequalities on the labour market emphasize the role of structural barriers and gender stereotypes. In this paper I am trying to answer the question whether it is either the existence of structural barriers or different attitudes of men and women towards work that is the cause of the obvious gender inequality on the Czech labour market. The analysis revealed that the differences in attitudes of men and women towards work are marginal and that many gender stereotypes according to which women are less ambitious employees than men are untenable. The structural barriers and gender stereotypes are thus possible to be considered as the principal causes of the gender inequalities on the Czech labour market. The findings are based on a quantitative analysis of data collected in a study of 5 510 respondents in 2005 in the Czech Republic.
The aim of this article is to fill in the gap in research focusing on the problem of the political participation of women in the Czech Republic. Based on text and interview analysis, it explains the role of women activists in Czech parliamentary parties in endorsing women for election to representative bodies. The article begins by describing the associations formed by women party activists and their position within the party structure, and then looks at the role of these associations in supporting women’s access to political structures. It also describes how women party activists take into account the barriers to women’s political participation and possible ways of removing these restraints. The final part introduces the hypothesis that although the creation of these associations seems to be a positive step towards improving women chances of gaining access to representative bodies, in their present form and circumstances they have no power to achieve any significant improvement in the status quo., Veronika Šprincová., tabulka, and Obsahuje bibliografii
Spermiogenesis and the spermatozoon were studied in the digenean Mesocoelium monas Rudolphi, 1819 (from the toad Bufo sp. in Gabon). An ultrastructural study revealed that spermiogenesis follows the usual pattern found in digeneans, i.e. proximo-distal fusion of axonemes with a median cytoplasmic process followed by elongation. The spermatozoon has two fully incorporated axonemes with the 9 +“1” trepaxonematan pattem. Indirect immunofluorescence localization of tubulin and fluorescent labelling of the nucleus were used to obtain additional information on the structure of the spermatozoon. It was thus shown that one of the axonemes is slightly shorter than the other (190 versus 220 pm) and that the filiform nucleus (65 pm in length) is located at the distal extremity of the spermatozoon (220 pm in length). Various monoclonal and polyclonal antibodies, specific to alpha, beta, acetylated-alpha, or general tubulin, were used and produced similar labelling.