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Evaluation of Acute Chromium (III) Toxicity in Relation to Daphnia Similis

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Journal of Water Resource and Protection 2011年第2期3卷 127-130页

作者： petr melnikov Tania C. m. de Freitas 不详

Acute chromium (III) toxicity in relation to Daphnia similis, most appropriate for Brazilian environment has been evaluated. The preliminary toxicity test showed that the median effective concentration was 10 mg/l. After having performed the final test, the immobility percentage was calculated for each concentration in relation to the total number of the used organisms within the chosen pH range. It was shown that the proposed methodology rendered realistic results and the 48-h CE50 value under the test conditions is 3.24 mg/l. The minimum concentration that did not show any toxicity to Daphnia similis was 2.5 mg of chromium (III) per liter. The obtained level is superior to the maximum limit recommended by the Brazilian norms, 0.5 mg/l.

关键词： Water pollution Chromium (III) Daphnia similis Acute toxicity test

The effect of neodymium substitution on the structural and magnetic properties of nickel ferrite

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Progress in Natural Science:materials International 2015年第3期25卷 215-221页

作者： ?srafil ?abiko?lu Levent Paral? Ondrej malina petr Novak Josef Kaslik Jiri Tucek Jiri Pechousek Jakub Navarik Oldrich Schneeweiss Celal Bayar University Faculty of Arts&SciencesDepartment of Physics 45140 Muradiye Celal Bayar University Department of Electronics and Automation Regional Centre of Advanced Technologies and materials Department of Experimental Physics and Physical ChemistryFaculty of SciencePalacky University Institute of Physics of materials of the Academy of Sciences of the Czech Republic

Nickel ferrite Ni Fe2O4 is a typical soft magnetic ferrite with high electrical resistivity used as high frequency magnetic material. Neodymium(Nd3+) doped Ni Fe2O4 materials were fabricated using solid state reaction. The properties of the obtained material were investigated by X-Ray Diffraction(XRD), Scanning Electron microscope(SEm), Fourier-Transform Infrared Spectroscopy(FT-IR), magnetic measurements on SQUID and m?ssbauer spectroscopy. It was found that the material consists of two different phases: Nd3+doped Ni Fet2O4and Nd Fe O3. The Nd3 ions occupy cation sites of the Ni Fe2O4 inverse spinel structure. NdFeO3 phase occurred when the level of Nd3+atoms exceed a percolation *** presence of both phases was confirmed by SEm observations. The m?ssbauer spectra analysis showed two sextets, which can be ascribed to iron atoms in tetrahedral and octahedral positions. From their intensities it is concluded that Nd3+occupies octahedral sites in the spinel structure of Ni Fe2O4, which were originally occupied by Ni2+.

关键词： NiFe2O4 Neodymium Solid-state reaction magnetic properties m?ssbauer spectroscopy

Sensitivity analysis of parameters and contrasting performance of ground filtering algorithms with UAV photogrammetry-based and LiDAR point clouds

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International Journal of Digital Earth 2020年第12期13卷 1672-1694页

作者： petr Klápště michal Fogl Vojtěch Barták Kateřina Gdulová Rudolf Urban Vítězslav moudrý Department of Applied Geoinformatics and Spatial Planning Faculty of Environmental SciencesCzech University of Life Sciences PragueKamýcká129Praha-Suchdol16500Czech Republic Department of Special Geodesy Faculty of Civil EngineeringCzech Technical University in PraguePragueCzech Republic

most ground filtering algorithms are primarily designed for airborne LiDAR point cloud processing and their successful use in identifying ground points from photogrammetric point clouds remains *** compared six ground filtering algorithms implemented in metashape,ArcGIS,CloudCompare,LAStools,and *** used UAV photogrammetry-based(acquired under leaf-off conditions)and airborne LiDAR(leaf-on)point clouds of the same area to:(i)compare accuracy of generated DTms;(ii)evaluate the effect of vegetation density and terrain slope on filtering accuracy;and(iii)assess which algorithm parameters have the greatest effect on the filtering *** results show that the performance of filtering algorithms was affected by the point cloud type,terrain slope and vegetation *** results were generally better for LiDAR(RmSE 0.13–0.19 m)than for photogrammetric(RmSE 0.19–0.23 m)point *** behavior in varying vegetation and terrain conditions was consistent for LiDAR point ***,when applied on photogrammetric point clouds,the algorithms’behavior was inconsistent,especially in areas of steep slope(except for the Progressive Triangulated Irregular Network in LAStools).Parameters related to the selection of the initial minimum elevation ground points were the most influential in all algorithms and point clouds.

关键词： DTm filtering LiDAR point cloud spoil heap UAV

Structural and compositional analysis of(InGa)(AsSb)/GaAs/GaP Stranski-Krastanov quantum dots

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Light(Science & Applications) 2021年第7期10卷 1313-1325页

作者： Raja S.R.Gajjela Arthur L.Hendriks James O.Douglas Elisa m.Sala petr Steindl petr Klenovský Paul A.J.Bagot michael P.moody Dieter Bimberg Paul m.Koenraad Department of Applied Physics Eindhoven University of Technology5612 AZ EindhovenThe Netherlands Department of materials University of OxfordParks RoadOxford OX13PHUK Center for Nanophotonics Institute for Solid State PhysicsTechnischeUniversität BerlinHardenbergstr.3610623 BerlinGermany EPSRC National Epitaxy Facility The University of SheffieldNorth CampusBroad LaneSheffield S37HQUK Department of Condensed matter Physics Faculty of ScienceMasaryk UniversityKotlářská267/261137 BrnoCzech Republic Huygens-Kamerlingh Onnes Laboratory Leiden UniversityP.O.Box 95042300 RA LeidenNetherlands Czech metrology Institute Okružní3163800 BrnoCzech Republic “Bimberg Chinese-German Center for Green Photonics”Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of Sciences at CIOMP13033 ChangchunChina

We investigated metal-organic vapor phase epitaxy grown(InGa)(AsSb)/GaAs/GaP Stranski–Krastanov quantum dots(QDs)with potential applications in QD-Flash memories by cross-sectional scanning tunneling microscopy(X-STm)and atom probe tomography(APT).The combination of X-STm and APT is a very powerful approach to study semiconductor heterostructures with atomic resolution,which provides detailed structural and compositional information on the *** rather small QDs are found to be of truncated pyramid shape with a very small top facet and occur in our sample with a very high density of∼4×10^(11) cm^(−2).APT experiments revealed that the QDs are GaAs rich with smaller amounts of In and *** element(FE)simulations are performed using structural data from X-STm to calculate the lattice constant and the outward relaxation of the cleaved *** composition of the QDs is estimated by combining the results from X-STm and the FE simulations,yielding∼In_(x)Ga_(1−x)As_(1−y)Sb_(y),where x=0.25–0.30 and y=0.10–***,the reported composition is in good agreement with the experimental results obtained by APT,previous optical,electrical,and theoretical analysis carried out on this material *** confirms that the InGaSb and GaAs layers involved in the QD formation have strongly intermixed.A detailed analysis of the QD capping layer shows the segregation of Sb and In from the QD layer,where both APT and X-STm show that the Sb mainly resides outside the QDs proving that Sb has mainly acted as a surfactant during the dot *** structural and compositional analysis provides a valuable insight into this novel QD system and a path for further growth optimization to improve the storage time of the QD-Flash memory devices.

关键词： analysis quantum sectional

Identification of altitude profiles in 3D geovisualizations:the role of interaction and spatial abilities

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International Journal of Digital Earth 2019年第2期12卷 156-172页

作者： petr Kubíček Čeněk Šašinka Zdeněk Stachoň Lukáš Herman Vojtěch Juřík Tomáš Urbánek Jiří Chmelík Department of Geography Faculty of ScienceMasaryk UniversityBrnoCzech Republic HUmE Lab Faculty of ArtsMasaryk UniversityBrnoCzech Republic Department of Psychology Faculty of ArtsMasaryk UniversityBrnoCzech Republic Department of Computer Graphics and Design Faculty of InformaticsMasaryk UniversityBrnoCzech Republic

Three-dimensional geovisualizations are currently pushed both by technological development and by the demands of experts in various applied *** the presented empirical study,we compared the features of real 3D(stereoscopic)versus pseudo 3D(monoscopic)geovisualizations in static and interactive digital elevation *** tested 39 high-school students in their ability to identify the correct terrain profile from digital elevation ***’performance was recorded and further analysed with respect to their spatial abilities,which were measured by a psychological mental rotation test and think aloud *** results of the study indicated that the influence of the type of 3D visualization(monoscopic/stereoscopic)on the performance of the users is not clear,the level of navigational interactivity has significant influence on the usability of a particular 3D visualization,and finally no influences of the spatial abilities on the performance of the user within the 3D environment were identified.

关键词： 3D geovisualizations stereoscopic and monoscopic 3D vision spatial abilities level of navigational interactivity

Exploring Sequence Space to Design Controllable G-Quadruplex Topology Switches

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CCS Chemistry 2022年第9期4卷 3036-3050页

作者： Jielin Chen mingpan Cheng petr Stadlbauer JiříŠponer Jean-Louis mergny Huangxian Ju Jun Zhou State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023 Institute of Biophysics of the Czech Academy of Sciences Královopolská135Brno 61265 Regional Centre of Advanced Technologies and materials Czech Advanced Technology and Research Institute(CATRIN)Palacky University OlomoucŠlechtitelů241/27Olomouc–Holice 78371 Laboratoire d’Optique et Biosciences Ecole PolytechniqueCNRSINSERMInstitut Polytechnique de ParisPalaiseau 91128

As nonclassical nucleic acid structures,G-quadruplexes(G4s)not only play important roles in gene regulation and stability maintenance,but are also widely used in *** diversity is one of the main factors explaining the popularity of G4s,but a comprehensive and integrated study of different factors determining G4 structural versatility is currently lacking.

关键词： G-quadruplex G-quadruplex topology Gswitch sequence composition structural versatility

SIRT1-dependent modulation of methylation and acetylation of histone H3 on lysine 9(H3K9)in the zygotic pronuclei improves porcine embryo development

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Journal of Animal Science and Biotechnology 2018年第2期9卷 339-350页

作者： Katerina Adamkova Young-Joo Yi Jaroslav petr Tereza Zalmanova Kristyna Hoskova Pavla Jelinkova Jiri moravec milena Kralickova miriam Sutovsky Peter Sutovsky Jan Nevoral Department of Veterinary Sciences Faculty of AgricultureFood and Natural ResourcesCzech University of Life Sciences Prague6-SuchdolPragueCzech Republic Division of Biotechnology SafetyEnvironment and Life Science InstituteCollege of Environmental and Bioresource SciencesChonbuk National UniversityIksan 54596South Korea Institute of Animal Science 10-UhrinevesPragueCzech Republic Proteomic Laboratory Biomedical Center of Faculty of Medicine in PilsenCharles UniversityPilsenCzech Republic Laboratory of Reproductive medicine of Biomedical Center Charles UniversityPilsenCzech Republic Department of Histology and Embryology Faculty of Medicine in PilsenCharles UniversityPilsenCzech Republic Division of Animal Science University of MissouriColumbiaMOUSA Departments of Obstetrics Gynecology and Women’s HealthUniversity of MissouriColumbiaMOUSA

Background: The histone code is an established epigenetic regulator of early embryonic development in *** lysine residue K9 of histone H3(H3 K9) is a prime target of SIRT1, a member of NAD+-dependent histone deacetylase family of enzymes targeting both histone and non-histone substrates. At present, little is known about SIRT1-modulation of H3 K9 in zygotic pronuclei and its association with the success of preimplantation embryo development. Therefore, we evaluated the effect of SIRT1 activity on H3 K9 methylation and acetylation in porcine zygotes and the significance of H3 K9 modifications for early embryonic ***: Our results show that SIRT1 activators resveratrol and BmL-278 increased H3 K9 methylation and suppressed H3 K9 acetylation in both the paternal and maternal pronucleus. Inversely, SIRT1 inhibitors nicotinamide and sirtinol suppressed methylation and increased acetylation of pronuclear H3 K9. Evaluation of early embryonic development confirmed positive effect of selective SIRT1 activation on blastocyst formation rate(5.2 ± 2.9% versus 32.9 ± 8.1% in vehicle control and BmL-278 group, respectively; P ≤ 0.05). Stimulation of SIRT1 activity coincided with fluorometric signal intensity of ooplasmic ubiquitin ligase mDm2, a known substrate of SIRT1 and known limiting factor of epigenome ***: We conclude that SIRT1 modulates zygotic histone code, obviously through direct deacetylation and via non-histone targets resulting in increased H3 K9 me3. These changes in zygotes lead to more successful pre-implantation embryonic development and, indeed, the specific SIRT1 activation due to BmL-278 is beneficial for in vitro embryo production and blastocyst achievement.

关键词： Embryonic development Epigenetics H3K9 methylation SIRT1 Sirtuin

Different Carbon Fractions in Soils and Their Relationship with Trace Elements Content

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Journal of Life Sciences 2011年第4期5卷 316-321页

作者： Lubica Pospisilova petr Skarpa marie Konecna Department of Agrochemistry Soil Science Microbiology and Plant Nutrition Faculty of Agriculture Mendel University in BrnoZem~ddlsk6 1 Brno 613 00 Czech Republic

Luvisols, Stagnogleys and Cambisols, although less fertile, are used intensively for mixed farming, grazing and as forestland. Therefore we aimed our study at determination of total organic carbon （TOC） content, humic substances （HS） content, humic acids （HA） content, fulvic acids （FA）, hot water extractable carbon （Chw） content and content total and labile trace elements content. Humic substances quality was assessed by HA/FA ratio and by coloured indexes measured in ultraviolet and visible UV-VIS spectral range. The total and labile contents of Zn, Cd, Cu, Co, Pb, mo and Se were determined by flame or electro-thermal atomic absorption spectrometry after extraction of the soil samples in the aqua regia （total content） and in the solution of 0.01 m CaCI2. Total and labile trace elements content was correlated with determined carbon fractions and soil reaction. Results showed that studied soils content low amount of TOC and had low quality of humic substances. HA/FA ratio was less than 1 and colour indexes were higher than 4. All determined carbon fractions correlated with labile form of Zn and Cd. Correlation between soil reaction and total zinc content was found. Significant effect of humic substances content on to water-soluble forms of heavy metals was detected.

关键词： Humic acids fulvic acids hot water extractable carbon humus fractionation labile trace elements total trace elements.

Real-World Safety and Performance of Saline Nasal Spray Products for Nasal Cleansing and Reducing Obstruction of the Nasal Cavity

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Open Journal of Respiratory Diseases 2023年第4期13卷 65-79页

作者： mathieu m. Albasser Gary Smith mariane Ballerini Fernandes Nisha Patel petr Novak martina Hagen GSK Consumer Healthcare SARL a Haleon company Nyon Switzerland Haleon Weybridge Surrey UK GSK Kingston upon Thames London UK Haleon Prague Czech Republic

Background and Objectives: Three post-marketing clinical follow-up studies were performed in Europe to confirm the safety and performance of four nonprescription, nasal cleansing medical devices: Otrivin Sea Water (OSW) pressurized spray, OSW with aloe vera (OSWAV), Otrisal 0.74% NaCl metered-Dose Spray (mDS), and Prorhinel spray. material and methods: Observational, single-arm, retrospective studies consisting of a single online questionnaire were performed between July 2021 and December 2021. Eligible participants were adults who used the device or supervised use of the device in a participant under 18 years of age within 6 months of completing the questionnaire. Demographics, safety, and device performance were assessed. Results: Based on questionnaires submitted on OSW (n = 556), OSWAV (n = 555), Otrisal mDS (n = 555), and Prorhinel (n = 555), proportions of users who reported safety events were 1.8% for OSW, 2.3% for OSWAV, 1.4% for Otrisal mDS, and 2.0% for Prorhinel. Proportions of users who indicated they were satisfied or very satisfied with device performance ranged from 72.0% - 89.0% across all devices. Device performance for all products was also supported for additional preventative and symptomatic uses through exploratory analyses. Conclusions and Significance: These data confirm device safety and performance of OSW, OSWAV, Otrisal mDS, and Prorhinel for their intended uses.

关键词： Saline Solution Sodium Chloride Common Cold Allergens Postmarketing Product Surveillance