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29812. The salinity tolerance of freshwater cyanobacterium Synechococcus sp. PCC 7942 is determined by Its ability for osmotic adjustment and presence of osmolyte sucrose
- Creator:
- Ladas, N. P. and Papageorgiou, G. C.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- absorption spectra, cell doubling, chlorophyll content and fluorescence, cytoplasmic osmolality, glucose, NaCl, saccharose, and sugars
- Language:
- Multiple languages
- Description:
- We investigated the factors that impose an upper limit of salinity tolerance to the unicellular freshwater cyanobacterium Synechococcus sp. PCC 7942. Above approx. 0.4 M NaCl, Synechococcus cells cease to proliferate, after having accumulated 0.3 M sucrose. Cells that pre-accumulated sucrose could tolerate up to 0.5 M NaCl, but not 0.6 M NaCl. After exposure to 0.5 M NaCl or higher, the cells were irreversibly modified becoming unable for osmotic volume adjustments. and N. P. Ladas, G. C. Papageorgiou.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29813. The Saxo turbine - an interesting selection for reliable and efficient operation
- Creator:
- Gale, Janez, Dolenc, Damir, Bergant, Anton, and Cizelj, Sandi
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- vertical axial water turbine, Saxo turbine, operation feedback, medium size HPP, and double-regulated turbine
- Language:
- English
- Description:
- Double-regulated vertical axial water turbine with conical distributor, which is worldwide known as a Saxo-type turbine, is the main subject of this paper. Due to continuous research, development and improvement, advance and compact structure, simplified civil construction works, reliability, ecological design and versatile applicability, the turbine became very recognizable product of company Litostroj Power, with over 30 successfully commissioned units in North American and Canadian market mainly. Authors see the Saxo turbine as one of the most interesting and suitable solutions for small and medium size hydro power plants. This paper aims to draw attention on this unique and interesting turbine design especially because experiences show that hydro power plant investors are somehow conservative and they mainly prefer and trust in more conventional turbine types i.e. Kaplan turbines and tubular turbines. The paper enlightens important design, hydraulic, economic and operation advantages of the Saxo-type turbines and points out most obvious advantages comparing to tubular and Kaplan type turbines. As an evidence of safe and reliable operation, there is a special section at the end of the paper which is focused on field-feedback experiences obtained during exptensive turbine testing at commissioning tests, final field performance acceptance tests and operation experiences. and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29814. The seismic response affection of the nuclear reactor WWER 1000 by nuclear fuel assemblies
- Creator:
- Hlaváč, Zdeněk and Zeman, Vladimír
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- reactor vibration, identification, seismic response, and accelerogram
- Language:
- English
- Description:
- The paper deals with mathematical modelling and computer simulation of the seismic response of chosen components of hte nuclear WWER 1999 reactor. The seismic response is investigated by numerical integration method in time domain. The seismic excitation is given by two horizontal and one vertical synthetic accelerograms at the level of the pressure vessel seating adjusted for a certain damping vallue 5 %. The main aim of the paper is seismic response assessment for two variants of nuclear fuel assemblies - VVANTAGE 6 and TVSA-T. The maximal values of displacements and linkages or component deformations are compared for both fuel assembly variants. and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29815. The sense of life as a subjective spiritual human experience: empirical study
- Creator:
- Ryś, Ewa
- Type:
- article, model:article, and TEXT
- Subject:
- spirituality, sense of meaning in life, and logotheory
- Language:
- Czech
- Description:
- Man’s spirituality is part of individual inner experience e.g. awareness of making one’s own choices, subjectivity, aspirations, preferred values and their criteria, open-mindedness towards oneself and others, readiness to contradict evil, and striving to realize the purpose of life. The multifaceted construct of SoL embraces: 1) life affirmation, 2) self-acceptance, 3) goal awareness, 4) sense of freedom, 5) valuation of future, and 6) attitude towards death. The objective of my empirical research was to determine the intensity of SoL among students of pedagogy and to establish which components of meaning of life co-condition the level of SoL intensity. Test group : a representative group of pedagogy students at the University of Szczecin: 683 people. The designed SoL test is based on the PIL (Purpose in Life) format- Crumbaugh-Maholick Purpose-in-Life Test. The results of research prove empirical theses stated on the grounds of logotheory and logotherapy (e.g. about the significance of the attitude towards death for the attitude towards life, and the sense of freedom as a mechanism facilitating transcendence).
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29816. The serological surveillance of several groups of patients using antigens of Encephalitozoon hellem and E. cuniculi antibodies to microsporidia in patients
- Creator:
- Kučerová-Pospíšilová, Zuzana and Ditrich, Oleg
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- microsporidia, Encephalitozoon cuniculi, Encephalitozoon hellem, and antimicrosporidial IgG antibodies
- Language:
- English
- Description:
- This study was undertaken to attempt to identify correlations between microsporidial seroprevalence data in man, clinical diseases and groups of people at the risk of HIV/AIDS infection. Groups of patients were selected according to the predilection of members of the genus Encephalitozoon for nervous and kidney tissue. Female prostitutes and alcohol and intravenous drug abusers were selected as groups at risk of HIV/AIDS infections. A total of 401 samples of human sera were examined for the presence of antimicrosporidial IgG antibodies by ELISA test with a titre of 600 considered borderline positivity. The highest occurrence of antimicrosporidial antibodies was found in the groups of alcohol abusers (16 % from 43 patients), intravenous drug abusers (11 % from 9 patients) and prostitutes (10 % from 80 women) for E. cuniculi antigen and in the groups of psychiatric patients (14 % from 44 patients), malaria patients (11 % from 38 patients) and alcohol abusers (7 % from 43 patients) for E. hellem antigen. The occurrence of specific antibodies of the six examined diagnostic units (glomerulonephritis chronica, pyelonephritis chronica, schizophrenia, dementia, multiple sclerosis and cerebral stroke) was statistically significant only in patients with pyelonephritis chronica and dementia (p < 0.05), No cases of microsporidial infection were found among the female prostitutes by parasitological examination, although one case of giardiasis was identified. Sera of patients with high anti-/:, cuniculi and anti-fc'. hellem antibodies (titres in ELISA of 600 and above) were confirmed by Western blot using E. cuniculi and E. hellem polypeptides, respectively. These results suggest that the examined patients could show residual antibodies from past or latent infections.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29817. The severity of muscle performance deterioration in sarcopenia correlates with circulating muscle tissue-specific miRNAs
- Creator:
- Valášková, Simona, Gažová, Andrea, Vrbová, Petra, Koller, Tomáš, Šalingová, Barbara, Adamičková, Adriana, Chomaničová, Nikola, Hulajová, Nikoleta, Payer, Juraj, and Kyselovič, Ján
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- fyziologie člověka, lékařství, human physiology, medicine, Sarcopenia, MiRNAs, Biomarker, 14, and 612
- Language:
- English
- Description:
- a1_Sarcopenia is defined as an age-associated loss of skeletal muscle function and muscle mass and is common in older adults. Sarcopenia as a disease is currently of interest not only to orthopedists and surgeons but also to internists, endocrinologists, rheumatologists, cardiologists, diabetologists, gynaecologists, geriatricians and paediatricians. In cooperation with the 5th Internal Medicine Clinic, we, as a unit of clinical research, aimed to describe a sarcopenic specific miRNA expression profile for disease diagnostics and classification of the severity of muscle performance deterioration. This study included a total of 80 patients (age 55-86 years) hospitalized at the V. Internal medicine clinic of LFUK and UNB with different severity of muscle performance deterioration. The study participants were evaluated and classified according to short physical performance battery score (SPPB). In this study, we investigated the role of circulating miRNAs in sarcopenia in the elderly. We hypothesized that sarcopenia effects the expression of muscle tissue-specific miRNAs (MyomiRNAs), which could be potentially reflected in the blood plasma miRNA expression profile. The expression of specific circulating miRNAs in patients with different muscle performances was analyzed. Patients’ blood plasma was evaluated for the expression of myomiRNAs: miRNA-29a, miRNA-29b, miRNA-1, miRNA-133a, miRNA-133b, miRNA-206, miRNA-208b and miRNA-499, and the data were correlated with diagnostic indicators of the disease. We showed a specific sarcopenia miRNA profile that could be considered a possible biomarker for the disease. Patients with low muscle performance showed increased miRNA-1, miRNA-29a and miRNA-29b expression and decreased for the miRNA-206, miRNA-133a, miRNA-133b, miRNA-208b and miRNA-499 expression., a2_ We show that the severity of muscle performance deterioration in sarcopenia correlates with specific miRNA expression. We also propose the profile of miRNAs expression in blood plasma as a specific biomarker for sarcopenia diagnostics. Future clinical studies will be necessary to eventually naturally have to elucidate the underlined molecular mechanism responsible for specific miRNAs expression in sarcopenia pathology and progression of the disease., Simona Valášková, Andrea Gažová, Petra Vrbová, Tomáš Koller, Barbara Šalingova, Adriana Adamičková, Nikola Chomaničová, Nikoleta Hulajová, Juraj Payer, Ján Kyselovič., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29818. The short- and long-term response of Scrippsiella trochoidea (Pyrrophyta) to solar ultraviolet radiation
- Creator:
- Guan, W. C. and Lu, S. H.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, growth, photochemical efficiency, Scrippsiella trochoidea, UVR, and ΦPSII
- Language:
- Multiple languages
- Description:
- To assess the short- and long-term impacts of UV radiation (UVR, 280-400 nm) on the microalga Scrippsiella trochoidea, we exposed cells to three different radiation treatments (PAB: 280-700 nm, PA: 320-700 nm, and P: 400-700 nm). A significant decrease in the photochemical efficiency (ΦPSII) at high irradiance (100% of incident solar radiation, 216.0 W m-2) was observed. Photoinhibition was reduced from 62.7 to 10.9% when the cells were placed in 12% solar radiation (26.1 W m-2). In long-term experiments (11 days) using batch cultures, cell densities during the first 5 days were decreased under treaments P, PA, and PAB, reflecting a change in the irradiance experienced in the laboratory to that of incident solar irradiance. Thereafter, specific growth rates increased and UV-induced photoinhibition decreased, indicating acclimation to solar UV. Cells were found to exhibit both higher ratios of repair to UV-related damage, shorter period for recovery and increased concentrations of UV-absorbing compounds (UVabc), whose maximum absorption was found to be at 336 nm. Our data indicate that S. trochoidea is sensitive to ultraviolet radiation, but was able to acclimate relatively rapidly (ca. 6 days) by synthesizing UVabc and by increasing the rates of repair processes of D1 protein in PSII. and W. C. Guan, S. H. Lu.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29819. The significance of baroreflex sensitivity in hypertensive subjects with stroke
- Creator:
- Denisa Čelovská, Jozef Staško, Jozef Gonsorčík, and Diab, A.
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, autonomní nervový systém, hypertenze, věk, autonomic nervous system, hypertension, age, baroreflex sensitivity, stroke, 14, and 612
- Language:
- English
- Description:
- The relationship between baroreflex sensitivity expressed in ms/mm Hg (BRS) or in Hz/mm Hg (BRSf) in hypertensives with stroke in comparison with a group of stroke-free patients was evaluated. Twenty-six patients (aged 66±10 years, 11 females/ 15 males) with a history of the first ever ischemic stroke (6 months and more after stroke onset), which was neuroradiologically confirmed, were studied. These were compared to 30 hypertensive patients without history of any cardiovascular event, being of similar age and sex. BRS and BRSf were determined by the sequence and spectral methods (fiveminute non-invasive beat-to-beat recording of blood pressure and inter-beat interval, controlled breathing at a frequency of 0.1 Hz). A significant negative correlation between spontaneous BRS and blood pressure (BP) represented by the grade of hypertension was present (r = -0.52, p<0.001). Differences between hypertensives with and without stroke were detected in BRS obtained by the spectral method (BRS spect p=0.0237, BRSf spect p=0.0285) or BRS obtained by sequence method (BRS seq p=0.0532, BRSf seq p=0.0273). The greatest decline in BRS values was in hypertensive stroke patients with metabolic syndrome, who had BRS values below 3 ms/mm Hg. We found out that BRS and BRSf were more impaired in stroke patients with essential hypertension even 6 months and more after stroke onset than in stroke-free hypertensive patients. This finding was independent of age-dependent decrease of BRS. Examination of baroreflex sensitivity as a marker of autonomic dysfunction along with global cardiovascular risk stratification of individuals seems to be a method for identifying patients at high residual cardiovascular risk., D. Čelovská ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29820. The significance of soil moisture in forecasting characteristics of flood events: A statistical analysis in two nested catchments
- Creator:
- Chifflard, Peter, Kranl, Julius, zur Strassen, Georg, and Zepp, Harald
- Type:
- article, model:article, and TEXT
- Subject:
- soil moisture, runoff prediction, catchment hydrology, spatial-temporal variability, and multivariate statistics
- Language:
- Slovak
- Description:
- We examine the feasibility and added value of upscaling point data of soil moisture from a small- to a mesoscale catchment for the purpose of single-event flood prediction. We test the hypothesis that in a given catchment, the present soil moisture status is a key factor governing peak discharge, flow volume and flood duration. Multiple regression analyses of rainfall, pre-event discharge, single point soil moisture profiles from representative locations and peak discharge, discharge duration, discharge volume are discussed. The soil moisture profiles are selected along a convergent slope connected to the groundwater in flood plain within the small-scale catchment Husten (2.6 km²), which is a headwater catchment of the larger Hüppcherhammer catchment (47.2 km², Germany). Results show that the number of explanatory variables in the regression models is higher in summer (up to 8 variables) than in winter (up to 3 variables) and higher in the meso-scale catchment than in the small-scale catchment (up to 2 variables). Soil moisture data from selected key locations in the small catchment improves the quality of regression models established for the meso-scale catchment. For the different target variables peak discharge, discharge duration and discharge volume the adding of the soil moisture from the flood plain and the lower slope as explanatory variable improves the quality of the regression model by 15%, 20% and 10%, respectively, especially during the summer season. In the winter season the improvement is smaller (up to 6%) and the regression models mainly include rainfall characteristics as explanatory variables. The appearance of the soil moisture variables in the stepwise regression indicates their varying importance, depending on which characteristics of the discharge are focused on. Thus, we conclude that point data for soil moisture in functional landscape elements describe the catchments’ initial conditions very well and may yield valuable information for flood prediction and warning systems.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public