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The concept of entropy is not uniquely relevant to the statistical mechanics but, among others, it can play pivotal role in the analysis of a time series, particularly the stock market data. In this area, sudden events are especially interesting as they describe abrupt data changes with potentially long-lasting effects. Here, we investigate the impact of such events on the entropy of financial time series. As a case study, we assume data of the Polish stock market, in the context of its main cumulative index, and discuss it for the finite time periods before and after outbreak of the 2022 Russian invasion of Ukraine. This analysis allows us to validate the entropy-based methodology in assessing changes in the market volatility, as driven by the extreme external factors. We show that some qualitative features of such market variations can be well captured in terms of the entropy. In particular, the discussed measure appears to highlight differences between data of the two considered timeframes in agreement with the character of their empirical distributions, which is not always the case in terms of the conventional standard deviation. Moreover, the entropy of cumulative index averages, qualitatively, the entropies of composing assets, suggesting capability for describing interdependencies between them. The entropy is also found to exhibit signatures of the upcoming extreme events. To this end, the role of recent war in shaping the current economic situation is briefly discussed.
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INTRODUCTION: Improper maintenance of the cleanliness of sand in sandboxes can be a source of human pathogenic helminths, including Toxocara spp., Enterobius vermicularis, Ascaris lumbricoides, leading to parasitic infections. AIM OF THE STUDY: The purpose of this study was to evaluate the sanitary condition of sandboxes in playgrounds and recreational areas in Warsaw for the presence of Human roundworm (Ascaris lumbricoides) and Toxocara spp. in sand. MATERIAL AND METHODS: 450 sand samples from 90 sandboxes in the city of Warsaw were analyzed. The flotation method was used for the study, and the material was evaluated using a light microscope. RESULTS. The conducted examinations did not reveal the presence of parasite eggs, indicating that hygiene rules were observed and appropriate recommendations were followed. CONCLUSIONS: The analyzed sand samples are free of the tested parasites.
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Areia , Toxocara , Animais , Humanos , Ascaris lumbricoides , Solo/parasitologia , PolôniaRESUMO
Introduction: Babesiosis is caused by one of several Babesia species. In Europe, B. divergens predominates in humans, while in North America it is B. microti. Babesia spp. infection in donors with a disease-free course of infection can be a major problem in blood recipients. A recipient with impaired immune system functions is at risk of full-blown development of the disease. In Poland and in most countries of the world, blood donors are not routinely tested for Babesia spp. infection. In our previous study, we detected Babesia venatorum DNA in blood donors, which was the reason for expanding the study to include more test subjects. Objective: The aim of this study was an attempt at estimating the prevalence of asymptomatic infection with Babesia spp. among blood donors from the Regional Centres for Blood Donation and Blood Treatment in Warsaw and Wroclaw. Materials and methods: The material for the study was whole blood from regular blood donors from two Regional Centre for Blood Donation and Blood Treatment in Warsaw and Wroclaw. Whole blood samples from 1,067 blood donors collected in June-July 2022 were analyzed. Blood collected directly from the donor during the blood donation procedure. All persons qualified by a doctor as a donor were selected for the study, regardless of age and sex. All subjects were informed in detail about the purpose of the study and gave their written consent. Isolation was made by using the Chelex 100 chelating resin, followed by the studying of the genetic material using the qPCR reaction. The results were analysed based on the amplification curve. Results: The protozoan Babesia spp. was not detected in the blood samples. Conclusions: The risk of blood-borne babesiosis is extremely low in Poland.
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Babesia microti , Babesia , Babesiose , Humanos , Babesia/genética , Babesiose/epidemiologia , Babesia microti/genética , Polônia/epidemiologia , Doadores de SangueRESUMO
INTRODUCTION AND OBJECTIVES: Blastocystis hominis s. l. is one of the most commonly detected protozoa in the human large intestine. The aim of the study was to determine the genetic subtypes of Blastocystis hominis s. l. occurring in humans in Poland. MATERIALS AND METHODS: Stool samples from patients diagnosed in the Laboratory of the Department of Parasitology, National Institute of Public Health National Institute of Hygiene (NIZP-PZH) and in the Parasitology Laboratory of the Hospital for Infectious Diseases in Warsaw were examined. Blastocystis subtypes were assayed based on the fragment of small-subunit ribosomal RNA gene sequences (SSU rDNA). RESULTS: The examined isolates were classified into five Blastocystis subtypes (STs), fifteen of which belonged to ST3, three to ST1, two to ST2, two to ST6, and one isolate belonged to ST7. In three cases the subtype of isolate was not identified. DISCUSSION AND CONCLUSIONS: In Poland, the subtypes ST1, ST2, ST3, ST4, ST6 and ST7 have been reported in humans so far. The ST6 and ST7 subtypes are rarely detected in humans in Europe. In Poland, the ST6 subtype was previously described in chickens. On the basis of the studies, it was found that Blastocystis isolated from humans in Warsaw show high genetic diversity. In order to determine the possible pathogenic potential of individual Blastocystis subtypes, special epidemiological studies are required.
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Infecções por Blastocystis/parasitologia , Blastocystis hominis/parasitologia , Diarreia/parasitologia , Fezes/parasitologia , Adulto , Animais , Infecções por Blastocystis/classificação , Infecções por Blastocystis/epidemiologia , Blastocystis hominis/classificação , DNA de Protozoário/genética , Diarreia/classificação , Diarreia/epidemiologia , Variação Genética , Humanos , Masculino , PolôniaRESUMO
Association between exercise-induced bronchoconstriction (EIB) and physical activity has not been investigated in a natural school environment in a general pediatric population. Our objective was to determine the prevalence of exercise-induced symptoms (cough, wheeze, chest tightness, dyspnea) and bronchospasm among schoolchildren during physical education (PE). A total of 557 schoolchildren from seven public schools were enrolled. Information regarding demographic characteristic, previously diagnosed asthma was obtained. All children attended 45-minute PE lesson with similar exercise intensity. Pulmonary function tests were performed before and immediately after PE lesson. The diagnosis of EIB was defined as a forced expiratory volume in one second (FEV1) decrease from baseline of more than or equal to 10% with exercise. Cough and dyspnea after exercise were recorded. A total of 557 participants were included into the analysis. After PE lesson, 15.3% children suffered from cough, 0.9% reported dyspnea, and 10.1% had more than 10% fall in FEV1 from baseline. Among all participants, 5.9% had doctors' diagnosed asthma, 4.8% of them were treated with inhaled corticosteroids (ICS). Among children with cough, 21.5% had asthma and 17.6% experienced EIB. Among asthmatics, 48.6% suffered from cough and 18.2% had more than 10% fall in FEV1 from baseline after PE lesson. EIB was not affected by age, gender, body mass index, asthma diagnosis, and ICS use. Only cough (odds ratio: 2.21, 95% confidence interval: 1.16-4.23; p = 0.0161) was independently associated with EIB. This study showed a high prevalence of exercise-induced cough and/or 10% fall in FEV1 during activity lesson in a natural school environment in a large urban population of schoolchildren. Our results call for another studies addressing the impact of environment on exercise-induced symptoms.
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Tosse/epidemiologia , Tosse/etiologia , Exercício Físico , Adolescente , Asma Induzida por Exercício/epidemiologia , Criança , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Projetos Piloto , Prevalência , Fatores de RiscoRESUMO
The generic name Blastocystis has been proposed at least twice for different organisms for which nomenclature is governed by the International Code of Zoological Nomenclature. Blastocystis Jaekel, 1918, is a junior homonym of the generic name Blastocystis Alexeieff, 1911. We propose the following Astroblastocystis nom. nov. as a new replacement name (neonym) for Blastocystis Jaekel, 1918.
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Equinodermos , AnimaisRESUMO
Blastocystis is one of the most frequently detected protozoa in the human large intestine. One of the most effective and cheap methods for detecting Blastocystis in faeces is culture on a special medium in anaerobic conditions. Sampling faeces using traditional containers and their transport to the laboratory has certain limitations: a sample taken in this way should reach the laboratory relatively quickly, moreover, some patients are uncomfortable during sampling and protection of material in this way. We propose utilizing a swab for sampling and transportation of the faeces samples to be examined for Blastocystis instead of using traditional containers. We believe this is an excellent method allowing the material to be transported over longer distances without additional, and sometimes expensive, safety measures, and at the same time permitting the possibility of obtaining living cells after a relatively long period of storage.
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Infecções por Blastocystis , Blastocystis , Infecções por Blastocystis/diagnóstico , Infecções por Blastocystis/parasitologia , Carvão Vegetal , Meios de Cultura , Fezes/parasitologia , HumanosRESUMO
In the framework of the mimetic approach, we study the [Formula: see text] gravity with the Lagrange multiplier constraint and the scalar potential. We introduce field equations for the discussed theory and overview their properties. By using the general reconstruction scheme we obtain the power law cosmology model for the [Formula: see text] case as well as the model that describes symmetric bounce. Moreover, we reconstruct model, unifying both matter dominated and accelerated phases, where ordinary matter is neglected. Using inverted reconstruction scheme we recover specific [Formula: see text] function which give rise to the de-Sitter evolution. Finally, by employing the perfect fluid approach, we demonstrate that this model can realize inflation consistent with the bounds coming from the BICEP2/Keck array and the Planck data. We also discuss the holographic dark energy density in terms of the presented [Formula: see text] theory. Thus, it is suggested that the introduced extension of the mimetic regime may describe any given cosmological model.
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Blastocystis cf. Blastocystis hominis is the most common unicellular parasite found in human and animal intestines. Little is known about the life cycle, transmission and mechanisms of pathogenesis for this parasite. The aim of this study was to obtain new data on the genetic diversity of Blastocystis in selected species of mammals found in the Bialowieza Primeval Forest (BPF), Poland, the best preserved lowland forest in temperate Europe. 113 faecal samples were collected in the period 2018-2020 from seven species of wild mammals occurring within the Polish part of BPF and its surroundings. Blastocystis was detected by molecular amplification and sequencing the small subunit rRNA gene. The overall prevalence of Blastocystis in animals was 8.9%. A larger number of stool samples (90) were collected from European bison and only for this species was it possible to calculate the prevalence of infection (5.6%). The isolates obtained from European bison were classified as ST1, ST3, ST5, ST7. Blastocystis was also detected in the grey wolf (Canis lupus) (ST5), wild boar (Sus scrofa) (ST5) and red deer (Cervus elaphus) (ST1). In conclusion, for the first time we have demonstrated the presence of Blastocystis in wild European bison. Preliminary studies have shown that Blastocystis is present in at least 4 species of wild mammals in the BPF area and that it exhibits great genetic diversity.
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The aim of this study was to describe the morphology and means of identification of helminths in native partridges (65) and introduced pheasants (32) in Poland and to determine the level of intestinal infection of these birds by helminths using parasitological and ecological indices. The birds were acquired during the hunting season in the years 2015-2017. Nematodes, Capillaria phasianina, cestodes, Railietina friedbergeri, and one trematode, Brachylaima sp. were recorded for the first time in partridges in Poland. Our findings indicate that parasites are more prevalent in pheasants (prevalence 70.4%) than in partridges (prevalence 50.0%). The component community and infracommunity of parasites of partridges are more diverse (Simpson's diversity index: 0.63 and mean Brillouin diversity index: 0.10 ± 0.17) and less dominated by a single parasite species (Capillaria sp., Berger-Parker dominance index: 0.53) than the pheasant parasite community (Simpson's diversity index: 0.07, mean Brillouin diversity index: 0.005 ± 0.02, dominant species Heterakis gallinarum, Berger-Parker dominance index: 0.96). There were statistically significant differences between partridges and pheasants in the Brillouin diversity index and in the prevalence of Heterakis gallinarum (55.6% in pheasants vs. 19.0 in partridges). There were significant differences between wild and farmed partridges in the prevalence of infection by Capillaria sp. (4.3% vs. 37.5%) and H. gallinarum (39.1 vs. 6.2%). In conclusion, the pheasant was shown to be a reservoir, carrier, and shedder of nematodes, which may increase the risk of infection in partridges.
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Recently introduced [Formula: see text] theory is generalized by adding dependence on the arbitrary scalar field [Formula: see text] and its kinetic term [Formula: see text], to explore non-minimal interactions between geometry, scalar and matter fields in context of the Gauss-Bonnet theories. The field equations for the resulting [Formula: see text] theory are obtained and show that particles follow non-geodesic trajectories in a perfect fluid surrounding. The energy conditions in the Friedmann-Lemaître-Robertson-Walker (FLRW) spacetime are discussed for the generic function [Formula: see text]. As an application of the introduced extensions, using the reconstruction techniques we obtain functions that satisfy common cosmological models, along with the equations describing energy conditions for the reconstructed [Formula: see text] gravity. The detailed discussion of the energy conditions for the de Sitter and power-law spacetimes is provided in terms of the fixed kinetic term i.e. in the [Formula: see text] case. Moreover, in order to check viability of the reconstructed models, we discuss the energy conditions in the specific cases, namely the [Formula: see text] and [Formula: see text] approaches. We show, that for the appropriate choice of parameters and constants, the energy conditions can be satisfied for the discussed scenarios.
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Blastocystis cf. hominis is an unicellular protozoan parasite commonly found in the gastrointestinal tract of humans and animals. Blastocystis is characterized by high morphological and genetic diversity. Studies based on the analysis of Blastocystis spp. small subunit ribosomal RNA genes (SSU rDNA) have identified 26 subtypes (ST) so far, including at least 10 isolated from humans (STs 1-9 and ST12). In 2017, stool samples from a dog and its two owners living in Gdynia, Poland were examined; all three were suffering from chronic diarrhoea. In addition, 30 faecal samples were also examined from 30 dogs kept in one of Warsaw's hotels for animals. Stool specimens were analyzed using anaerobic cultivation at 37°C with a modified Jones' medium and molecular methods (PCR). Phylogenetic analysis using Bayesian inference was performed. Vacuolar forms of Blastocystis were identified in the stool samples of the dog and its owners; Blastocystis were not detected in any sample from the dogs living in the animal hotel. Based on the phylogenetic analysis, the obtained isolates were classified as subtype ST3 (for Owner 1) and subtype ST7 (for Owner 2 and the dog). To the best of our knowledge, the present study is the first to evaluate the presence of Blastocystis in canines in Poland, including domestic dogs.
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Infecções por Blastocystis , Blastocystis , Animais , Teorema de Bayes , Blastocystis/genética , Infecções por Blastocystis/epidemiologia , Infecções por Blastocystis/veterinária , DNA de Protozoário , Diarreia , Cães , Fezes , Variação Genética , Filogenia , Polônia/epidemiologiaRESUMO
With the continuous expansion of single cell biology, the observation of the behaviour of individual cells over extended durations and with high accuracy has become a problem of central importance. Surprisingly, even for yeast cells that have relatively regular shapes, no solution has been proposed that reaches the high quality required for long-term experiments for segmentation and tracking (S&T) based on brightfield images. Here, we present CellStar, a tool chain designed to achieve good performance in long-term experiments. The key features are the use of a new variant of parametrized active rays for segmentation, a neighbourhood-preserving criterion for tracking, and the use of an iterative approach that incrementally improves S&T quality. A graphical user interface enables manual corrections of S&T errors and their use for the automated correction of other, related errors and for parameter learning. We created a benchmark dataset with manually analysed images and compared CellStar with six other tools, showing its high performance, notably in long-term tracking. As a community effort, we set up a website, the Yeast Image Toolkit, with the benchmark and the Evaluation Platform to gather this and additional information provided by others.