91 research outputs found
K-Ar dating of amphiboles from andesite of complex dyke in Dubie (Southern Poland)
This study presents the results of radiometric K-Ar measurements on separated amphiboles from the andesite of the Dubie complex dyke. The data obtained cover the period of (291.3 ± 6.4) Ma, which corresponds to Carboniferous-Permian transition. The age is contemporaneous to the rhyodacitic and basaltoid volcanism of the Kraków region
Humour and the stretchy temporality of peer conflict in a group early childhood setting: an analysis of relational power
While research on children’s humour is growing, few investigations have focused on how children use humour in conflict interactions, and specifically in group early childhood settings. Using data extracts from a project that investigated children’s naturally occurring conflict interactions in a multi-ethnic early childhood setting, we use interactional sociolinguistics to analyse how children used humour at unexpected moments during conflict situations. The analysis probes different meanings carried in the children’s use of humour, illustrating how humour intersected with personal and relational power to resolve or defuse conflict, or to coerce compliance with existing peer relational positions. The analysis broadens understandings of the significance of humour in children’s lives in early childhood settings, and particularly in the context of conflict interactions that have a ‘stretchy temporality’ connecting interactive moves to others in the past, and to existing power positions in peer relationships
VIBRATION DIAGNOSTICS OF FOOTBRIDGE WITH USE OF ROTATION SENSOR
The benefits of the additional measurement of rotational degrees of free-dom on the performance of the vibration diagnosis of bridges are studied in this paper. The common vibrational diagnostics that uses translational degrees of freedom is extended by measurements of rotations. The study is curried out on a footbridge and the presence of damage as well as its location and size is determined with use of FEM updating procedure. The results showed that rotational degrees of freedom significantly improve the effectiveness of the vibrational method
Evaluation of superoxide dismutase activity and its impact on semen quality parameters of infertile men.
The evaluation of superoxide dismutase (SOD) activity, as one of the most important antioxidative defence enzymes, in seminal plasma of patients consulting for male infertility was presented in the article. The study included also the determination of its influence on selected human semen quality parameters. The material represents semen samples obtained from 15 men, which were divided into two groups: Group I (n=10) including patients consulting for infertility and Group II (n=5) containing healthy sperm donors as a control. All of the semen samples were cryopreserved and stored in liquid nitrogen. The frozen samples were thawed at the same time and then SOD activity was determined spectrophotometrically. The analysis of the investigations results indicates a significantly lower semen SOD activity detected in oligoasthenozoospermic patients, comparing to the activity found in normospermic men. The study showed a positive correlation between SOD activity in seminal plasma and semen quality parameters--sperm concentration and overall motility, which are regarded as the most important for normal fertilizing ability of the spermatozoa. Significantly lower SOD activity in seminal plasma of infertile patients, comparing to healthy sperm donors, as well as positive correlation and beneficial impact of SOD activity on human semen quality parameters seem to confirm the observations, that decreased seminal plasma scavenger antioxidant capacity, particularly in form of low SOD activity, can be responsible for male infertility. This trial shows that SOD activity survey in seminal plasma could be a useful tool for determining sperm fertilization potential and could improve the diagnosis of male infertility
GENEROWANIE MOSTKÓW DISIARCZKOWYCH W BIAŁKACH – RÓŻNORODNOŚĆ STRUKTURALNA I FUNKCJONALNA BIAŁEK DSBA
Blue-light-activated phototropin2 trafficking from the cytoplasm to Golgi/post-Golgi vesicles
Phototropins are plasma membrane-localized UVA/blue light photoreceptors which mediate phototropism, inhibition of primary hypocotyl elongation, leaf positioning, chloroplast movements, and stomatal opening. Blue light irradiation activates the C-terminal serine/threonine kinase domain of phototropin which autophosphorylates the receptor. Arabidopsis thaliana encodes two phototropins, phot1 and phot2. In response to blue light, phot1 moves from the plasma membrane into the cytosol and phot2 translocates to the Golgi complex. In this study the molecular mechanism and route of blue-light-induced phot2 trafficking are demonstrated. It is shown that Atphot2 behaves in a similar manner when expressed transiently under 35S or its native promoter. The phot2 kinase domain but not blue-light-mediated autophosphorylation is required for the receptor translocation. Using co-localization and western blotting, the receptor was shown to move from the cytoplasm to the Golgi complex, and then to the post-Golgi structures. The results were confirmed by brefeldin A (an inhibitor of the secretory pathway) which disrupted phot2 trafficking. An association was observed between phot2 and the light chain2 of clathrin via bimolecular fluorescence complementation. The fluorescence was observed at the plasma membrane. The results were confirmed using co-immunoprecipitation. However, tyrphostin23 (an inhibitor of clathrin-mediated endocytosis) and wortmannin (a suppressor of receptor endocytosis) were not able to block phot2 trafficking, indicating no involvement of receptor endocytosis in the formation of phot2 punctuate structures. Protein turnover studies indicated that the receptor was continuously degraded in both darkness and blue light. The degradation of phot2 proceeded via a transport route different from translocation to the Golgi complex
Spatio-temporal distribution of cell wall components in the placentas, ovules and female gametophytes of Utricularia during pollination
In most angiosperms, the female gametophyte is hidden in the mother tissues and the
pollen tube enters the ovule via a micropylar canal. The mother tissues play an essential role in
the pollen tube guidance. However, in Utricularia, the female gametophyte surpasses the entire
micropylar canal and extends beyond the limit of the integument. The female gametophyte then
invades the placenta and a part of the central cell has direct contact with the ovary chamber. To date,
information about the role of the placenta and integument in pollen tube guidance in Utricularia,
which have extra-ovular female gametophytes, has been lacking. The aim of this study was to
evaluate the role of the placenta, central cell and integument in pollen tube pollen tube guidance in
Utricularia nelumbifolia Gardner and Utricularia humboldtii R.H. Schomb. by studying the production
of arabinogalactan proteins. It was also determined whether the production of the arabinogalactan
proteins is dependent on pollination in Utricularia. In both of the examined species, arabinogalactan
proteins (AGPs) were observed in the placenta (epidermis and nutritive tissue), ovule (integument,
chalaza), and female gametophyte of both pollinated and unpollinated flowers, which means that the
production of AGPs is independent of pollination; however, the production of some AGPs was lower
after fertilization. There were some differences in the production of AGPs between the examined
species. The occurrence of AGPs in the placental epidermis and nutritive tissue suggests that they
function as an obturator. The production of some AGPs in the ovular tissues (nucellus, integument)
was independent of the presence of a mature embryo sac
Refusal to take sick leave after being diagnosed with a communicable disease as an estimate of the phenomenon of presenteeism in Poland
Work Ability Index (WAI) values in a sample of the working population in Poland
Introduction: Ability to work is most often defined as a relationship between a person’s resources and requirements specific to a particular type of work. It is the result of interaction between job requirements in terms of physical and mental strain, capabilities and skills of the employee, as well as his/her health condition and own evaluation of functioning in a given organizational and social situation. Objective: The primary objective of the study was to evaluate the current value of the Work Ability Index (WAI) in a sample of employees in Poland. Material and methods: The study sample was selected purposefully from 422,000 employees covered by the largest occupational health provider in Poland. The standard WAI questionnaire provided by CAWI (Computer-Assisted Web Interview) methodology was voluntary and completed anonymously by 688 employees within 12 months (0.16% response rate). The results were statistically analyzed using the Pearson’s chi-squared test and correlation coefficient, independent-sample T test and one-way analysis of variance (p<0.05). Results: It was found that the average value of WAI was 37.5 ± 7.7, and 37% of the participants represented low to moderate ability to work. The results showed no significant correlation between the WAI value and its 7 compounds and demographic variables. Nonetheless, a dependency between WAI level and industrial branch was observed. Conclusions: Subjects with moderate and low WAI (1/3 of the study population) had particular indications to implement prophylactic actions, especially for the health care employees and civil servants, whose ability to work may be subject to accelerated deterioration
Factors associated with fear of childbirth among Polish pregnant women
The purpose of our study was to elucidate the association between obstetric and psychological factors and fear of childbirth (FOC) during the third trimester of pregnancy and to identify women at risk of severe FOC in Poland. An additional goal of the study was to verify the Polish version of the Wijma Delivery Expectancy Questionnaire (W-DEQ) and to establish its psychometric characteristics. Cross-sectional study with a total of 359 women recruited during routine visits to an antenatal clinic in Poland during the third trimester (≥ 27 weeks gestation). The survey included obstetric details (parity, obstetric history and preferred mode of delivery), and standardized psychological measures: the W-DEQ (fear of childbirth) and the EPDS (depressive symptoms). We demonstrated the satisfactory psychometric properties of the Polish version of the W-DEQ. Our findings confirm the one-factor structure found by the authors of the original version of the scale. A greater FOC was
reported by women with unplanned pregnancies, women whose preferred mode of delivery was a cesarean section, and women who had previously undergone psychiatric treatment. The risk factors for severe FOC were depression, unplanned pregnancy or parity, and disagreement with the birth plan proposed by the obstetrician. The W-DEQ is a widely used, valid instrument for the assessment of FOC in pregnant women and can be used in Poland. Findings support the key role of obstetric and psychological variables in predicting fear of childbirth
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