822 research outputs found
WORLD ECONOMIC RECESSION VS. LABOUR MARKET GLOBALIZATION
Стаття присвячена оцінці впливу глобалізації і світової кризи на розвиток польської економіки. Визначено тенденції розвитку ринку праці в країнах Європейської спільноти. Проаналізовано роль держави у регулюванні процесів економічної взаємодії. Розглянуто моделі глобалізації на основі утворення регіональних об’єднань. Запропоновано рекомендації для адаптації польського ринку праці до нових економічних умов.The paper is dealt with evaluation of labour market globalization and global economic recession impacts on Polish economic growth. Trends of labour market changes in EU countries are determined. The role of the government in regulation of economic interactions processes is analyzed. The paper also considers models of globalization on the basis of developing regional systems. Some guidelines are proposed to adapt Polish labour market to new economic conditions
Numerical Simulations of Torsional Alfv\'en Waves in Axisymmetric Solar Magnetic Flux Tubes
We investigate numerically Alfv\'en waves propagating along an axisymmetric
and non-isothermal solar flux tube embedded in the solar atmosphere. The tube
magnetic field is current-free and diverges with height, and the waves are
excited by a periodic driver along the tube magnetic field lines. The main
results are that the two wave variables, the velocity and magnetic field
perturbations in the azimuthal direction, behave differently as a result of
gradients of physical parameters along the tube. To explain these differences
in the wave behavior, the time evolution of the wave variables and the
resulting cutoff period for each wave variable are calculated, and used to
determine regions in the solar chromosphere where strong wave reflection may
occur.Comment: Submitted to Solar Physics (accepted
miR393 contributes to the embryogenic transition induced in vitro in Arabidopsis via the modification of the tissue sensitivity to auxin treatment
miR393 molecules are believed to regulate the expression of the auxin receptors of the TAAR clade. Considering the central role of auxin in the induction of somatic embryogenesis (SE) in plant explants cultured in vitro, the involvement of miR393 in the embryogenic transition of somatic cells has been hypothesised. To verify this assumption, the reporter, overexpressor and mutant lines in genes encoded MIR393 and TIR1/AFB proteins of the F-box family were analysed during SE in Arabidopsis. Expression profiling of MIR393a and MIR393b, mature miR393 and the target genes (TIR1, AFB1, AFB2, AFB3) were investigated in explants undergoing SE. In addition, the embryogenic potential of various genotypes with a modified activity of the MIR393 and TIR1/AFB targets was evaluated. The distinct increase in the accumulation of miR393 that was coupled with a notable down-regulation of TIR1 and AFB2 targets was observed at the early phase of SE induction. Relevant to this observation, the GUS/GFP monitored expression of MIR393, TIR1 and AFB2 transcripts was localised in explant tissue undergoing SE induction. The results suggest the miR393-mediated regulation of TIR1 and AFB2 during embryogenic transition induced in Arabidopsis and a modification of the explant sensitivity to auxin treatment is proposed as underlying this regulatory pathway
miR160 and miR166/165 Contribute to the LEC2-Mediated Auxin Response Involved in the Somatic Embryogenesis Induction in Arabidopsis
MicroRNAs are non-coding small RNA molecules that are involved in the
post-transcriptional regulation of the genes that control various developmental
processes in plants, including zygotic embryogenesis (ZE). miRNAs are also believed
to regulate somatic embryogenesis (SE), a counterpart of the ZE that is induced in
vitro in plant somatic cells. However, the roles of specific miRNAs in the regulation of
the genes involved in SE, in particular those encoding transcription factors (TFs) with
an essential function during SE including LEAFY COTYLEDON2 (LEC2), remain mostly
unknown. The aim of the study was to reveal the function of miR165/166 and miR160
in the LEC2-controlled pathway of SE that is induced in in vitro cultured Arabidopsis
explants.In ZE, miR165/166 controls the PHABULOSA/PHAVOLUTA (PHB/PHV) genes,
which are the positive regulators of LEC2, while miR160 targets the AUXIN RESPONSE
FACTORS (ARF10, ARF16, ARF17) that control the auxin signaling pathway, which plays
key role in LEC2-mediated SE. We found that a deregulated expression/function of
miR165/166 and miR160 resulted in a significant accumulation of auxin in the cultured
explants and the spontaneous formation of somatic embryos. Our results show that
miR165/166 might contribute to SE induction via targeting PHB, a positive regulator of
LEC2 that controls embryogenic induction via activation of auxin biosynthesis pathway
(Wójcikowska et al., 2013). Similar to miR165/166, miR160 was indicated to control
SE induction through auxin-related pathways and the negative impact of miR160 on
ARF10/ARF16/ARF17 was shown in an embryogenic culture. Altogether, the results
suggest that the miR165/166- and miR160-node contribute to the LEC2-mediated
auxin-related pathway of embryogenic transition that is induced in the somatic cells of
Arabidopsis. A model summarizing the suggested regulatory interactions between the
miR165/166-PHB and miR160-ARF10/ARF16/ARF17 nodes that control SE induction
in Arabidopsis was proposed
Gentisic Acid, Salicylic Acid, Total Phenolic Content and Cholinesterase Inhibitory Activities of Red Wines Made from Various Grape Varieties
Alzheimer’s disease is characterised by a decrease in acetylcholine (ACh) levels in the brain due to the activity of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). As a result, disorders in cholinergic transmission are observed, leading to cognitive impairment. In this work, the inhibition of AChE and BChE activities by red wines made of various grape varieties was determined for the first time. There was no significant difference in the polyphenol content between the grape varieties; nevertheless, there were significant differences in the content of gentisic acid and salicylic acid, and in the inhibition of AChE and BChE between the wine samples. A statistically significant correlation between AChE inhibitory activity and salicylic acid, as well as between BChE inhibitory activity and total phenolic content, was recorded. In model solution studies, it was shown that salicylic acid effectively inhibited BChE activity at concentrations similar to the maximum concentrations found in the test wines. Hierarchical cluster analysis (HCA) revealed that the wines could be divided into three groups. Cabernet Sauvignon and Syrah wines had the highest content of salicylic acid and AChE inhibitory activity, as well as low BChE inhibitory activity. Pinot noir, Tempranillo, Regent and Rondo wines showed the lowest content of salicylic acid and low AChE inhibitory activity. Garnacha tinta, Merlot, Montepulciano and Negroamaro wines had a medium content of salicylic acid, and the highest or medium BChE inhibitory activity. This work is important for both the wine industry and for health protection
Epigenetic Regulation of Auxin-Induced Somatic Embryogenesis in Plants
Somatic embryogenesis (SE) that is induced in plant explants in response to auxin
treatment is closely associated with an extensive genetic reprogramming of the cell transcriptome.
The significant modulation of the gene transcription profiles during SE induction results from the
epigenetic factors that fine-tune the gene expression towards embryogenic development. Among
these factors, microRNA molecules (miRNAs) contribute to the post-transcriptional regulation of
gene expression. In the past few years, several miRNAs that regulate the SE-involved transcription
factors (TFs) have been identified, and most of them were involved in the auxin-related processes,
including auxin metabolism and signaling. In addition to miRNAs, chemical modifications of DNA
and chromatin, in particular the methylation of DNA and histones and histone acetylation, have been
shown to shape the SE transcriptomes. In response to auxin, these epigenetic modifications regulate
the chromatin structure, and hence essentially contribute to the control of gene expression during SE
induction. In this paper, we describe the current state of knowledge with regard to the SE epigenome.
The complex interactions within and between the epigenetic factors, the key SE TFs that have been
revealed, and the relationships between the SE epigenome and auxin-related processes such as auxin
perception, metabolism, and signaling are highlighted
Gravity in International Finance: Evidence From Fees on Equity Transactions
We shed light on the impact of institutional quality and information barriers on trade in financial services using a novel panel data set on revenue earned on domestic and crossborder equity securities underwriting transactions. Our data set covers 91,51
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