49 research outputs found
International comparison of motor abilities and floorball skills in U-11 to U-14 teams from the Czech Republic and Australia
Floorball is a young and rapidly developing team game. At the world floorball championships, the considerable disparity in performance can be seen between the individual countries. The aim of this study was to compare the level of floorball skills and motor abilities of children in the U-11 - U-14 age category at floorball clubs in the Czech Republic and Australia. The players from FBŠ Slavia Pilsen clubs (Czech Republic) (n=18; 12.1y±1.0; 155.4cm±10.6; 44.7kg±12.1) and Peninsula Floorball club (Australia) (n=18; 12.7y±1.0; 160.7cm±12.0; 53.2kg±11.6) participated in this study. To compare the tested groups, 6 items (3 motor abilities, 3 floorball skills) were used from the test battery prepared by the Czech Floorball Association for the given age category. In motor abilities, a statistically and substantially significant difference was found only for one item (Illinois agility test without stick). In floorball skills, a statistically and substantially significant difference was found for all of the tested items. Only for one criterion of the Shooting test, namely the time required for performing the task, the difference was not statistically significant, and substantial significance reached only a medium effect. The presented results clearly indicate the different level of floorball skills between the Czech and Australian floorball players in the age category tested by us
The annual recurrence risk model for tailored surveillance strategy in patients with cervical cancer
Purpose:
Current guidelines for surveillance strategy in cervical cancer are rigid, recommending the same strategy for all survivors. The aim of this study was to develop a robust model allowing for individualised surveillance based on a patient's risk profile.
Methods:
Data of 4343 early-stage patients with cervical cancer treated between 2007 and 2016 were obtained from the international SCCAN (Surveillance in Cervical Cancer) consortium. The Cox proportional hazards model predicting disease-free survival (DFS) was developed and internally validated. The risk score, derived from regression coefficients of the model, stratified the cohort into significantly distinctive risk groups. On its basis, the annual recurrence risk model (ARRM) was calculated.
Results:
Five variables were included in the prognostic model: maximal pathologic tumour diameter; tumour histotype; grade; number of positive pelvic lymph nodes; and lymphovascular space invasion. Five risk groups significantly differing in prognosis were identified with a five-year DFS of 97.5%, 94.7%, 85.2% and 63.3% in increasing risk groups, whereas a two-year DFS in the highest risk group equalled 15.4%. Based on the ARRM, the annual recurrence risk in the lowest risk group was below 1% since the beginning of follow-up and declined below 1% at years three, four and >5 in the medium-risk groups. In the whole cohort, 26% of recurrences appeared at the first year of the follow-up, 48% by year two and 78% by year five.
Conclusion:
The ARRM represents a potent tool for tailoring the surveillance strategy in early-stage patients with cervical cancer based on the patient's risk status and respective annual recurrence risk. It can easily be used in routine clinical settings internationally
Aligned nanofibres made of poly(3-hydroxybutyrate) grafted to hyaluronan for potential healthcare applications
In this work, a hybrid copolymer consisting of poly(3-hydroxybutyrate) grafted to hyaluronic acid (HA) was synthesised and characterised. Once formed, the P(3HB)-g-HA copolymer was soluble in water allowing a green electrospinning process. The diameters of nanofibres can be tailored by simply varying the Mw of polymer. The optimization of the process allowed to produce fibres of average diameter in the range of 100-150 nm and low polydispersity. The hydrophobic modification has not only increased the fibre diameter, but also the obtained layers were homogenous. At the nanoscale, the hybrid copolymer exhibited an unusual hairy topography. Moreover, the hardness and tensile properties of the hybrid were found to be superior compared to fibres made of unmodified HA. Particularly, this reinforcement was achieved at the longitudinal direction. Additionally, this work reports the use in the composition of a water-soluble copolymer containing photo cross-linkable moieties to produce insoluble materials post-electrospinning. The derivatives as well as their nanofibrous mats retain the biocompatibility of the natural polymers used for the fabrication
New trends in the economic systems management in the context of modern global challenges
New trends in the economic systems management in the context of modern global challenges: collective monograph / scientific edited by M. Bezpartochnyi, in 2 Vol. // VUZF University of Finance, Business and Entrepreneurship. – Sofia: VUZF Publishing House “St. Grigorii Bogoslov”, 2020. – Vol. 1. – 309 p
The Physiology and Proteomics of Drought Tolerance in Maize: Early Stomatal Closure as a Cause of Lower Tolerance to Short-Term Dehydration?
Understanding the response of a crop to drought is the first step in the breeding of tolerant genotypes. In our study, two maize (Zea mays L.) genotypes with contrasting sensitivity to dehydration were subjected to moderate drought conditions. The subsequent analysis of their physiological parameters revealed a decreased stomatal conductance accompanied by a slighter decrease in the relative water content in the sensitive genotype. In contrast, the tolerant genotype maintained open stomata and active photosynthesis, even under dehydration conditions. Drought-induced changes in the leaf proteome were analyzed by two independent approaches, 2D gel electrophoresis and iTRAQ analysis, which provided compatible but only partially overlapping results. Drought caused the up-regulation of protective and stress-related proteins (mainly chaperones and dehydrins) in both genotypes. The differences in the levels of various detoxification proteins corresponded well with the observed changes in the activities of antioxidant enzymes. The number and levels of up-regulated protective proteins were generally lower in the sensitive genotype, implying a reduced level of proteosynthesis, which was also indicated by specific changes in the components of the translation machinery. Based on these results, we propose that the hypersensitive early stomatal closure in the sensitive genotype leads to the inhibition of photosynthesis and, subsequently, to a less efficient synthesis of the protective/detoxification proteins that are associated with drought tolerance
The map of quercetin and its derivatives occurence in parts of onion (Allium cepa L.) varieties
Determination of quercetin and its derivatives in dependency on the onion variety and the part from which it was extracted
Overexpression of TET dioxygenases in seminomas associates with low levels of DNA methylation and hydroxymethylation.
Germ cell tumors and particularly seminomas reflect the epigenomic features of their parental primordial germ cells, including genomic DNA hypomethylation and expression of pluripotent cell markers. Because the DNA hypomethylation might be a result of TET dioxygenase activity, we examined expression of TET1-3 enzymes and the level of their product, 5-hydroxymethylcytosine, in a panel of histologically characterized seminomas and non-seminomatous germ cell tumors. Expression of TET dioxygenase mRNAs was quantified by real-time PCR. TET1 expression and the level of 5-hydroxymethylcytosine were examined immunohistochemically. Quantitative assessment of 5-methylcytosine and 5-hydroxymethylcytosine levels was done by the liquid chromatography-mass spectroscopy technique. We found highly increased expression of TET1 dioxygenase in most seminomas and strong TET1 staining in seminoma cells. Isocitrate dehydrogenase 1 and 2 mutations were not detected, suggesting the enzymatic activity of TET1. The levels of 5-methylcytosine and 5-hydroxymethylcytosine in seminomas were found decreased in comparison to non-seminomatous germ cell tumors and healthy testicular tissue. We propose that TET1 expression should be studied as a potential marker of seminomas and mixed germ cell tumors and we suggest that elevated expression of TET dioxygenase enzymes is associated with the maintenance of low DNA methylation levels in seminomas. This "anti-methylator" phenotype of seminomas is in contrast to the CpG island methylator phenotype observed in a fraction of tumors of various types
PALM-USM v1.0: A new urban surface model integrated into the PALM large-eddy simulation model
Urban areas are an important part of the climate system and many
aspects of urban climate have direct effects on human health and
living conditions. This implies that reliable tools for local urban
climate studies supporting sustainable urban planning are
needed. However, a realistic implementation of urban canopy
processes still poses a serious challenge for weather and climate
modelling for the current generation of numerical models. To address
this demand, a new urban surface model (USM), describing the surface
energy processes for urban environments, was developed and
integrated as a module into the PALM large-eddy simulation
model. The development of the
presented first version of the USM
originated from modelling the urban heat island during summer heat
wave episodes and thus implements primarily processes important in
such conditions. The USM contains a multi-reflection radiation model
for shortwave and longwave radiation with an integrated model of
absorption of radiation by resolved plant canopy (i.e. trees,
shrubs). Furthermore, it consists of an energy balance solver for
horizontal and vertical impervious surfaces, and thermal diffusion in
ground, wall, and roof materials, and it includes a simple model for
the consideration of anthropogenic heat sources. The USM was
parallelized using the standard Message Passing Interface and
performance testing demonstrates that the computational costs of the
USM are reasonable on typical clusters for the tested
configurations. The module was fully integrated into PALM and is
available via its online repository under the GNU General Public License
(GPL). The USM was tested on a summer heat-wave episode for
a selected Prague crossroads. The general representation of the
urban boundary layer and patterns of surface temperatures of various
surface types (walls, pavement) are in good agreement with in
situ
observations made in Prague. Additional simulations were performed
in order to assess the sensitivity of the results to uncertainties
in the material parameters, the domain size, and the general effect
of the USM itself. The first version of the USM is limited to the
processes most relevant to the study of summer heat waves and serves as
a basis for ongoing development which will address additional
processes of the urban environment and lead to improvements to
extend the utilization of the USM to other environments and conditions
Validation of the PALM model system 6.0 in a real urban environment: A case study in Dejvice, Prague, the Czech Republic
In recent years, the PALM 6.0 modelling system has been rapidly developing its capability to simulate physical processes within urban environments. Some examples in this regard are energy-balance solvers for building and land surfaces, a radiative transfer model to account for multiple reflections and shading, a plant-canopy model to consider the effects of plants on flow (thermo)dynamics, and a chemistry transport model to enable simulation of air quality. This study provides a thorough evaluation of modelled meteorological, air chemistry, and ground and wall-surface quantities against dedicated in situ measurements taken in an urban environment in Dejvice, Prague, the Czech Republic. Measurements included monitoring of air quality and meteorology in street canyons, surface temperature scanning with infrared cameras, and monitoring of wall heat fluxes. Large-eddy simulations (LES) using the PALM model driven by boundary conditions obtained from a mesoscale model were performed for multiple days within two summer and three winter episodes characterized by different atmospheric conditions. For the simulated episodes, the resulting temperature, wind speed, and chemical compound concentrations within street canyons show a realistic representation of the observed state, except that the LES did not adequately capture night-Time cooling near the surface for certain meteorological conditions. In some situations, insufficient turbulent mixing was modelled, resulting in higher near-surface concentrations. At most of the evaluation points, the simulated surface temperature reproduces the observed surface temperature reasonably well for both absolute and daily amplitude values. However, especially for the winter episodes and for modern buildings with multilayer walls, the heat transfer through walls is not well captured in some cases, leading to discrepancies between the modelled and observed wall-surface temperature. Furthermore, the study corroborates model dependency on the accuracy of the input data. In particular, the temperatures of surfaces affected by nearby trees strongly depend on the spatial distribution of the leaf area density, land surface temperatures at grass surfaces strongly depend on the initial soil moisture, wall-surface temperatures depend on the correct setting of wall material parameters, and concentrations depend on detailed information on spatial distribution of emissions, all of which are often unavailable at sufficient accuracy. The study also points out some current model limitations, particularly the implications of representing topography and complex heterogeneous facades on a discrete Cartesian grid, and glass facades that are not fully represented in terms of radiative processes. Our findings are able to validate the representation of physical processes in PALM while also pointing out specific shortcomings. This will help to build a baseline for future developments of the model and improvements of simulations of physical processes in an urban environment