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31.
Jakub Marynowicz Mateusz Lango Damian Horna Karol Kikut Marcin Andrzejewski 《Biology of sport / Institute of Sport》2022,39(2):245
The purpose of this study was to determine the effectiveness of white-box decision tree models (DTM) for predicting the rating of perceived exertion (RPE). The second aim was to examine the relationship between RPE and external measures of intensity in youth soccer training at the group and individual level. Training load data from 18 youth soccer players were collected during an in-season competition period. A total of 804 training observations were undertaken, with a total of 43 ± 17 sessions per player (range 12–76). External measures of intensity were determined using a 10 Hz GPS and included total distance (TD, m/min), high-speed running distance (HSR, m/min), PlayerLoad (PL, n/min), impacts (n/min), distance in acceleration/deceleration (TD ACC/TD DEC, m/min) and the number of accelerations/decelerations (ACC/DEC, n/min). Data were analysed with decision tree models. Global and individualized models were constructed. Aggregated importance revealed HSR as the strongest predictor of RPE with relative importance of 0.61. HSR was the most important factor in predicting RPE for half of the players. The prediction error (root mean square error [RMSE] 0.755 ± 0.014) for the individualized models was lower compared to the population model (RMSE 1.621 ± 0.001). The findings demonstrate that individual models should be used for the assessment of players’ response to external load. Furthermore, the study demonstrates that DTM provide straightforward interpretation, with the possibility of visualization. This method can be used to prescribe daily training loads on the basis of predicted, desired player responses (exertion). 相似文献
32.
The role of the N-terminal polypeptide fragment of the immunoglobulin l-chain in V domain packing stability, and the flexibility of the whole chain was approached by molecular dynamics simulation. The observations were supported by experimental analysis. The N-terminal polypeptide fragment appeared to be the low-stability packing element in the V domain. At moderately elevated temperature it may be replaced at its packing locus by Congo red and then removed by proteolysis. After removal of Congo red by adsorption to (diethylamino)ethyl (DEAE) cellulose, the stability of complete L chain and of L chain devoid of the N-terminal polypeptide fragment were compared. The results indicated that the N-terminal polypeptide fragment plays an essential role in the stability of the V domain. Its removal makes the domain accessible for ANS and Congo red dye binding without heating. The decreased domain stability was registered in particular as increased root mean square (RMS) fluctuation and higher susceptibility to proteolytic attack. The long-range effect was most clearly manifested at 340 K as independent V and C domain fluctuation in the l-chain devoid of the N-terminal polypeptide fragment. This is likely due to the lack of direct connections between the N- and C-termini of the V domain polypeptide. In a complete V domain the connection involves residues 8-12 and 106-110 in particular. Partial or complete disruption of this connection increases the freedom of V domain rotation, while its increased cohesion strengthens the coupling of the V and C domains, making the whole L chain less flexible. 相似文献
33.
Adam Konefał Andrzej Orlef Marcin Łaciak Aleksander Ciba Marek Szewczuk 《Reports of Practical Oncology and Radiotherapy》2012,17(6):339-346
BackgroundHigh-energy photon and electron therapeutic beams generated in medical linear accelerators can cause the electronuclear and photonuclear reactions in which neutrons with a broad energy spectrum are produced. A low-energy component of this neutron radiation induces simple capture reactions from which various radioisotopes originate and in which the radioactivity of a linac head and various objects in the treatment room appear.AimThe aim of this paper is to present the results of the thermal/resonance neutron fluence measurements during therapeutic beam emission and exemplary spectra of gamma radiation emitted by medical linac components activated in neutron reactions for four X-ray beams and for four electron beams generated by various manufacturers’ accelerators installed in typical concrete bunkers in Polish oncological centers.Materials and methodsThe measurements of neutron fluence were performed with the use of the induced activity method, whereas the spectra of gamma radiation from decays of the resulting radioisotopes were measured by means of a portable high-purity germanium detector set for field spectroscopy.ResultsThe fluence of thermal neutrons as well as resonance neutrons connected with the emission of a 20 MV X-ray beam is ~106 neutrons/cm2 per 1 Gy of a dose in water at a reference depth. It is about one order of magnitude greater than that for the 15 MV X-ray beams and about two orders of magnitude greater than for the 18–22 MeV electron beams regardless of the type of an accelerator.ConclusionThe thermal as well as resonance neutron fluence depends strongly on the type and the nominal potential of a therapeutic beam. It is greater for X-ray beams than for electrons. The accelerator accessories and other large objects should not be stored in a treatment room during high-energy therapeutic beam emission to avoid their activation caused by thermal and resonance neutrons. Half-lives of the radioisotopes originating from the simple capture reaction (n,γ) (from minutes to hours) are long enough to accumulate radioactivity of components of the accelerator head. The radiation emitted by induced radioisotopes causes the additional doses to staff operating the accelerators. 相似文献
34.
Powierska-Czarny J Miścicka-Sliwka D Czarny J Grzybowski T Wozniak M Drewa G Czechowicz W Sir J 《Acta biochimica Polonica》2003,50(4):1195-1203
Analysis of microsatellite instability (MI) and loss of heterozygosity (LOH) is recommended for screening patients with sporadic and hereditary malignancies. This study shows an application of a fluorescent hexaplex PCR system for microsatellite typing on A.L.F. DNA Sequencer (Pharmacia Biotech). This technique detects changes in microsatellites providing a time-efficient, reliable and accurate method for MI and LOH analyses. The Fragment Manager software was used for automated size calculation and quantitation of DNA fragments, enabling rapid and precise measurement of allelic ratios. We examined 70 breast cancer and 70 control DNA specimens, classified all the patterns of microsatellite alterations, and set up MI and LOH assessment criteria for the automated multiplex fluorescent method. 相似文献
35.
The ultrastructure of spermatozoa of the acotylean Phaenocelis peleca and the cotylean Boninia divae is described. All spermatozoa are filiform and biflagellate with a 9+"1" microtubular pattern in the axoneme. Sperm characters
in P. peleca follow the morphologies described for other acotyleans, with axonemes exiting the sperm shaft at the distal end and remaining
in close contact with the sperm membrane. The nucleus occupies the proximal region of the shaft, and two types of dense bodies
and mitochondria are located at the distal end. Unlike other members of the Cotylea, the axonemes of B. divae spermatozoa are incorporated into the sperm shaft, leaving the shaft at some distance from the distal end and then remaining
free. This type of morphology is characteristic for acotyleans. Additionally, the spermatozoa of B. divae contain only one type of dense bodies plus a unique structure, which we call a central core. The nucleus in this species
is unique as well; it shows periodic constrictions and rings of electron-dense granules, characters that further contribute
to the distinct status of Boniniidae. 相似文献
36.
The purpose of the present work was to determine if selected fungal strains belonging to wood-rotting Basidiomycetes are able to grow on and to solubilize different insoluble oxides in solid media. Twenty-eight strains of white rot fungi were checked for their growth on oxide-amended media (ZnO, CaO, Cu2O). All strains displayed growth on Zn-amended plates but to a different extent, and Cu2O-amended plates turned out to be the most toxic oxide. Most of the tested strains solubilized oxalates and produced noticeable clear zones under the mycelium. These clear zones were tested for the presence of organic acids, the level of which was clearly elevated upon exposure of fungal strains to insoluble oxides. We determined the presence of oxalic, malic, and formic acids, with oxalic acid the predominant one. 相似文献
37.
38.
Bartlomiej Perek Agnieszka Malinska Sebastian Stefaniak Danuta Ostalska-Nowicka Marcin Misterski Maciej Zabel Anuj Suri Michal Nowicki 《PloS one》2013,8(8)
Background
Venous aortocoronary graft arterialization may precede a preterm occlusion in some coronary artery bypass grafting (CABG) patients. The aim of the present study was to identify ultrastructural variations in the saphenous vein wall that may have an impact on the development of venous graft disease in CABG patients.Methods
The study involved 365 consecutive patients with a mean age of 62.9±9.4 years who underwent isolated CABG. The thickness and area of the whole venous wall, the tunica intima, the tunica media and the adventitia and the number and shape (length, thickness and length/thickness ratio) of the nuclei in the medial smooth muscle cells nuclei in the distal saphenous vein segments were evaluated by ultrastructural studies. Patients were followed up for 41 to 50 months (mean 45.1±5.1). Saphenous vein graft patency was assessed by follow-up coronary angiography. Logistic regression models were used to identify independent risk factors for late graft failure.Results
In 71 patients significant lesions in the saphenous vein grafts were observed. The whole venous wall thickness (437.5 µm vs. 405.5 µm), tunica media thickness (257.2 µm vs. 211.5 µm), whole venous wall area (2.23 mm2 vs. 2.02 mm2) and tunica media area (1.09 mm2 vs. 0.93 mm2) were significantly larger for this group of patients than for those without graft disease. In the latter group more elongated smooth muscle cell nuclei (higher length/thickness ratio) were found in the tunica media of the saphenous vein segments. Thickening of the saphenous vein tunica media and chunky smooth muscle cell nuclei were identified as independent risk factors for graft disease development.Conclusions
Saphenous vein tunica media hypertrophy (resulting in wall thickening) and chunky smooth muscle cell nuclei might predict the development of venous graft disease. 相似文献39.
Radoslaw Charkiewicz Jacek Niklinski Jürgen Claesen Anetta Sulewska Miroslaw Kozlowski Anna Michalska-Falkowska Joanna Reszec Marcin Moniuszko Wojciech Naumnik Wieslawa Niklinska 《Translational oncology》2017,10(3):450-458
Advances in molecular analyses based on high-throughput technologies can contribute to a more accurate classification of non–small cell lung cancer (NSCLC), as well as a better prediction of both the disease course and the efficacy of targeted therapies. Here we set out to analyze whether global gene expression profiling performed in a group of early-stage NSCLC patients can contribute to classifying tumor subtypes and predicting the disease prognosis. Gene expression profiling was performed with the use of the microarray technology in a training set of 108 NSCLC samples. Subsequently, the recorded findings were validated further in an independent cohort of 44 samples. We demonstrated that the specific gene patterns differed significantly between lung adenocarcinoma (AC) and squamous cell lung carcinoma (SCC) samples. Furthermore, we developed and validated a novel 53-gene signature distinguishing SCC from AC with 93% accuracy. Evaluation of the classifier performance in the validation set showed that our predictor classified the AC patients with 100% sensitivity and 88% specificity. We revealed that gene expression patterns observed in the early stages of NSCLC may help elucidate the histological distinctions of tumors through identification of different gene-mediated biological processes involved in the pathogenesis of histologically distinct tumors. However, we showed here that the gene expression profiles did not provide additional value in predicting the progression status of the early-stage NSCLC. Nevertheless, the gene expression signature analysis enabled us to perform a reliable subclassification of NSCLC tumors, and it can therefore become a useful diagnostic tool for a more accurate selection of patients for targeted therapies. 相似文献
40.
Tadeusz Osadnik Joanna Katarzyna Strzelczyk Rafa? Regu?a Kamil Bujak Martyna Fronczek Ma?gorzata Gonera Marcin Gawlita Jaros?aw Wasilewski Andrzej Lekston Anna Kurek Marek Gierlotka Przemys?aw Trzeciak Micha? Hawranek Zofia Ostrowska Andrzej Wiczkowski Lech Poloński Mariusz G?sior 《PloS one》2016,11(3)