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Evaluating the species use of protected area networks is of considerable worldwide importance, especially as a feedback for policy-makers and the conservation community. Based on the data of an annual, citizen-science monitoring programme of long tradition (2004–2015), we test the hypothesis that the European Natura 2000 network protects high quality habitats preferentially settled by wintering waterbird species in a central European State (the Czech Republic). We analysed species-specific variables (protection status, flyway population trend and numbers, geographical distribution, and foraging guild) explaining the proportions of numbers in Natura 2000 and individual-species changes in numbers inside and outside Natura 2000. The proportions of numbers in individual species were generally low in Natura 2000 sites. The observed pattern revealed the expected higher preference of protected Annex I species for Natura 2000 sites compared to other species and showed foraging guilds having significant differences in Natura 2000 preference, with high preference in herbivores and fish-eaters and low preference in invertebrate-eaters compared to omnivores. Northern species also showed a high preference for Natura 2000. The predicted prevalence of a higher rate of increase, or lower rate of decrease, inside Natura 2000, indicating that Natura 2000 facilitated the species' distribution changes, was not shown; instead, the positive and negative trends inside Natura 2000 were almost equivalent. We concluded that the low preference for Natura 2000, the distribution changes shifting species outside Natura 2000, and limits to the carrying capacity of the protected network sites, could all make an issue in effectively safeguarding the non-breeding populations of waterbirds. The extension of the Natura 2000 network to facilitate their wintering requirements and distribution changes is therefore a high priority. © 2018 Elsevier Ltd

Background A highly regulated trafficking of cargo vesicles in eukaryotes performs protein delivery to a variety of cellular compartments of endomembrane system. The two main routes, the secretory and the endocytic pathways have pivotal functions in uni- and multi-cellular organisms. Protein delivery and targeting includes cargo recognition, vesicle formation and fusion. Developing new tools to modulate protein trafficking allows better understanding the endomembrane system mechanisms and their regulation. The compound Sortin2 has been described as a protein trafficking modulator affecting targeting of the vacuolar protein carboxypeptidase Y (CPY), triggering its secretion in Saccharomyces cerevisiae. Results A reverse chemical-genetics approach was used to identify key proteins for Sortin2 bioactivity. A genome-wide Sortin2 resistance screen revealed six yeast deletion mutants that do not secrete CPY when grown at Sortin2 condition where the parental strain does: met18, sla1, clc1, dfg10, dpl1 and yjl175w. Integrating mutant phenotype and gene ontology annotation of the corresponding genes and their interactome pointed towards a high representation of genes involved in the endocytic process. In wild type yeast endocytosis towards the vacuole was faster in presence of Sortin2, which further validates the data of the genome-wide screen. This effect of Sortin2 depends on structural features of the molecule, suggesting compound specificity. Sortin2 did not affect endocytic trafficking in Sortin2-resistant mutants, strongly suggesting that the Sortin2 effects on the secretory and endocytic pathways are linked. Conclusions Overall, the results reveal that Sortin2 enhances the endocytic transport pathway in Saccharomyces cerevisiae. This cellular effect is most likely at the level where secretory and endocytic pathways are merged. Them Sortin2 specificity over the endomembrane system places it as a powerful biological modulator for cell biology.

BACKGROUND: A highly regulated trafficking of cargo vesicles in eukaryotes performs protein delivery to a variety of cellular compartments of endomembrane system. The two main routes, the secretory and the endocytic pathways have pivotal functions in uni- and multi-cellular organisms. Protein delivery and targeting includes cargo recognition, vesicle formation and fusion. Developing new tools to modulate protein trafficking allows better understanding the endomembrane system mechanisms and their regulation. The compound Sortin2 has been described as a protein trafficking modulator affecting targeting of the vacuolar protein carboxypeptidase Y (CPY), triggering its secretion in Saccharomyces cerevisiae. RESULTS: A reverse chemical-genetics approach was used to identify key proteins for Sortin2 bioactivity. A genome-wide Sortin2 resistance screen revealed six yeast deletion mutants that do not secrete CPY when grown at Sortin2 condition where the parental strain does: met18, sla1, clc1, dfg10, dpl1 and yjl175w. Integrating mutant phenotype and gene ontology annotation of the corresponding genes and their interactome pointed towards a high representation of genes involved in the endocytic process. In wild type yeast endocytosis towards the vacuole was faster in presence of Sortin2, which further validates the data of the genome-wide screen. This effect of Sortin2 depends on structural features of the molecule, suggesting compound specificity. Sortin2 did not affect endocytic trafficking in Sortin2-resistant mutants, strongly suggesting that the Sortin2 effects on the secretory and endocytic pathways are linked. CONCLUSIONS: Overall, the results reveal that Sortin2 enhances the endocytic transport pathway in Saccharomyces cerevisiae. This cellular effect is most likely at the level where secretory and endocytic pathways are merged. Them Sortin2 specificity over the endomembrane system places it as a powerful biological modulator for cell biology.

Diplomová práce se zabývá návrhem rámu kola BMX, jehož konstrukce vychází ze současně používaného rámu. Důvodem rekonstrukce současného rámu je zvýšení jeho životnosti, snížení hmotnosti a zlepšení jízdních vlastností. V úvodu jsou uvedeny možnosti stanovení zatížení teoreticky. Následuje reálné měření zatížení a jeho vyhodnocení. Dále je vytvořen virtuální MKP model stávajícího rámu se zatížením podle naměřených hodnot, jsou vytipována kritická místa na rámu a je proveden výpočet životnosti stávající konstrukce. Na závěr je proveden návrh nového rámu, na kterém je vhodnou konstrukční úpravou zvýšena jeho životnost. Práce je doplněna výrobním výkresem rámu., This thesis deals with BMX bike frame, whose design is based on the currently used frame. The reason for the reconstruction of the current frame is to increase its service life, reduced weight and improved handling. In the introduction, given the possibility of establishing zátěžného spectrum theory. Followed by real measurement load spectrum and its evaluation. Furthermore, it created a virtual model of the present MKP frame under load measurements are identified and critical points on the frame and the calculation is carried out the life of existing structures. At the conclusion there is a proposal for a new frame, which is an appropriate structural adjustment increased durability. The work is complemented by the production drawing frame., Import 04/07/2011

BACKGROUND: The onset of differentiation entails modifying the gene expression state of cells, to allow activation of developmental programs that are maintained repressed in the undifferentiated precursor cells [1, 2]. This requires a mechanism to change gene expression on a genome-scale. Recent evidence suggests that in mammalian stem cells, derepression of developmental regulators during differentiation involves a shift from stalled to productive elongation of their transcripts [3-5], but factors mediating this shift have not been identified and the evidence remains correlative. RESULTS: We report the identification of the MINIYO (IYO) gene, a positive regulator of transcriptional elongation that is essential for cells to initiate differentiation in Arabidopsis. IYO interacts with RNA polymerase II and the Elongator complex and is required to sustain global levels of transcriptional elongation activity, specifically in differentiating tissues. Accordingly, IYO is expressed in embryos, meristems, and organ primordia and not in mature tissues. Moreover, differential subcellular protein distribution further refines the domain of IYO function by directing nuclear accumulation, and thus its transcriptional activity, to cells initiating differentiation. Importantly, IYO overexpression induces premature cell differentiation and leads to meristem termination phenotypes. CONCLUSIONS: These findings identify IYO as a necessary and sufficient factor for initiating differentiation in Arabidopsis and suggest that the targeted nuclear accumulation of IYO functions as a transcriptional switch for this fate transition.