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Changes in the adult sex ratio of six duck species breeding populations over two decades

Avian Research 2024年第2期15卷 202-210页

作者： Monika Homolkova petr Musil Diego Pavon-Jordan Dorota Gajdosova Zuzana Musilova Sarka neuzilova Jan Zouhar Department of Ecology Faculty of Environmental SciencesCzech University of Life Sciences PragueKamýcka 129CZ-16521Prague–SuchdolCzech Republic Department of Terrestrial Ecology Norwegian Institute for Nature Research(NINA)PO Box 5685 TorgardenTrondheimN-7485Norway Department of Econometrics Faculty of Informatics and StatisticsUniversity of Economicsnam.W.Churchilla 4CZ-13067Prague 3Czech Republic

Despite all efforts,long-term changes in the adult sex ratios of breeding duck populations are still unclear;this uncertainty is especially true for male-bias populations,which are often under the scrutiny of researchers lacking convenient results for the active protection of endangered *** with male-bias populations are usually strongly affected by a decline in population size that leads to a higher extinction *** this study,we examined our long-term data of the abundance of breeding populations in six duck species(Mallard Anas platyrhynchos,Gadwall Mareca strepera,Red-crested Pochard netta rufina,Common Pochard Aythya ferina,Tufted Duck Aythya fuligula,and Common Goldeneye Bucephala clangula)from fishponds in South Bohemia,Czechia,between 2004 and *** evidence was used to assess long-term changes in the adult sex ratio in these breeding populations and investigate the possible effects of the nAO index(north Atlantic Oscillation index)on them,indicating climate conditions in *** determined a long-term decrease of the proportion of females in the breeding season in two of the six examined species:Common Pochard and Red-crested Pochard,which is driven by the long-term increase in the number of males in contrast to the decreasing or stable number of females likely caused by different migration behaviours between females and *** the case of Common Pochard,in breeding populations,we estimated 60-65%of males in the early 2000s rising to 75-80%in the early ***,we establish no significant effects linked to climate conditions of the previous winter in these species as a crucial cause of the changes of the proportion of females in the breeding population.

关键词： Adult sex ratio Breeding population Population dynamics Red-listed species Waterfowl Winter weather conditions

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Cadaverine and putrescine exposure influence carbon and nitrogen cycling genes in water and sediment of the Yellow River

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Journal of Environmental Sciences 2024年第8期142卷 236-247页

作者： Wanghong Su Qiaoling Yu Jiawei Yang Qian Han Sijie Wang petr Hedenec Xiaochen Wang Ruijun Wan-Yan Huan Li School of Public Health Lanzhou UniversityLanzhou 730000China 2 Institute for Tropical Biodiversity and Sustainable DevelopmentUniversity Malaysia Terengganu21030Kuala NerusTerengganuMalaysia State Key Laboratory of Grassland Agro-ecosystems Center for Grassland MicrobiomeCollege of pastoral agriculture science and technology Lanzhou UniversityLanzhou 730000China

The response patterns of microbial functional genes involved in biogeochemical cycles to cadaver decay is a central topic of recent environmental ***,the response mechanisms and pathways of the functional genes associated with the carbon(C)and nitrogen(n)cycling to cadaveric substances such as cadaverine and putrescine remain *** study explored the variation of functional genes associated with C fixation,C degradation and n cycling and their influencing factors under cadaverine,putrescine and mixed *** results showed only putrescine significantly increased the alpha diversity of C fixation genes,while reducing the alpha diversity of n cycling genes in *** the C cycling,the mixed treatment significantly decreased the total abundance of reductive acetyl-CoA pathway genes(i.e.,acsB and acsE)and lig gene linked to lignin degradation in water,while only significantly increasing the hydroxypropionate-hydroxybutylate cycle(i.e.,accA)gene abundance in *** the n cycling,mixed treatment significantly decreased the abundance of the nitrification(i.e.,amoB),denitrification(i.e.,nirS3)genes in water and the assimilation pathway gene(i.e.,gdhA)in *** factors(i.e.,total carbon and total nitrogen)were all negatively associated with the genes of C and n ***,cadaverine and putrescine exposure may inhibit the pathway in C fixation and n cycling,while promoting C *** findings can offer some new insight for the management of amine pollution caused by animal cadavers.

关键词： Carbon cycling nitrogen cycling Cadaverine Putrescine Pollution management

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An integrated microfluidic platform for nucleic acid testing

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Microsystems & nanoengineering 2024年第3期10卷 181-194页

作者： Antao Sun petra Vopařilová Xiaocheng Liu Bingqian Kou TomášŘezníček TomášLednický Sheng ni JiříKudr Ondřej Zítka Zdenka Fohlerová petr Pajer Haoqing Zhang Pavel neužil Ministry of Education Key Laboratory of Micro and nano Systems for Aerospace School of Mechanical EngineeringNorthwestern Polytechnical University127 West Youyi RoadXi’anShaanxi 710072P.R.China Department of Chemistry and Biochemistry Mendel University in BrnoZemědělská161300 BrnoCzech Republic ITD Tech s.r.o Osvoboditelů100573581 BohumínCzech Republic Central European Institute of Technology Brno University of TechnologyPurkyňova 123Brno 61200Czech Republic Department of Electronic and Computer Engineering The Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong SARChina Department of Microelectronics Faculty of Electrical Engineering and CommunicationBrno University of TechnologyTechnická3058/10Brno 61600Czech Republic Military Health Institute U Vojenskénemocnice 120016200 Praha 6Czech Republic The Key Laboratory of Biomedical Information Engineering of Ministry of Education School of Life Science and TechnologyXi’an Jiaotong UniversityXi’anShaanxi 710049P.R.China Bioinspired Engineering and Biomechanics Center(BEBC) Xi’an Jiaotong UniversityXi’an 710049P.R.China

This study presents a rapid and versatile low-cost sample-to-answer system for SARS-CoV-2 *** system integrates the extraction and purification of nucleic acids,followed by amplification via either reverse transcriptionquantitative polymerase chain reaction(RT–qPCR)or reverse transcription loop-mediated isothermal amplification(RT–LAMP).By meeting diverse diagnostic and reagent needs,the platform yields testing results that closely align with those of commercial RT-LAMP and RT‒qPCR *** advantages of our system include its speed and *** assay is completed within 28 min,including sample loading(5 min),ribonucleic acid(RnA)extraction(3 min),and RT-LAMP(20 min).The cost of each assay is≈$9.5,and this pricing is competitive against that of Food and Drug Administration(FDA)-approved commercial *** some RnA loss during on-chip extraction is observed,the platform maintains a potential limit of detection lower than 297 *** makes the system particularly useful in environments where centralized laboratories are either unavailable or inconveniently *** key feature is the platform’s versatility,allowing users to choose between RT‒qPCR or RT‒LAMP tests based on specific requirements.

关键词： testing maintain versatile

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numerical Simulation of Separated Flows in Channels

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Journal of Thermal Science 2012年第2期21卷 145-153页

作者： petr Louda Jaromír Príhoda petr Sváek Karel Kozel Czech Technical University in Prague Fac. of Mechanical Engineering Karlovo nám. 13 CZ-121 35 Praha 2 Institute of Thermomechanics AS CR v.v.i. Dolejkova 5 CZ-182 00 Praha 8

The work deals with numerical modelling of turbulent flows in channels with an expansion of the cross-section where flow separation and reattachment occur. The performance of several eddy viscosity models and an explicit algebraic Reynolds stress model (EARSM) is studied. The used test cases are flows in channels with various backward facing steps where the step is perpendicular or inclined and the top wall is parallel or deflected. Furthermore, a channel with the circular ramp is considered. The numerical solution is achieved by the finite volume method or by the finite element method. The results of both numerical approaches are compared.

关键词： backward facing step flow EARSM model SST model

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Accurate large-scale simulations of siliceous zeolites by neural network potentials

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npj Computational Materials 2022年第1期8卷 1662-1673页

作者： Andreas Erlebach petr n.chtigall LukášGrajciar Department of Physical and Macromolecular Chemistry Charles UniversityHlavova 812800Prague 2Czech Republic

The computational discovery and design of zeolites is a crucial part of the chemical *** highly accurate while computational feasible protocol for identification of hypothetical siliceous frameworks that could be targeted experimentally is a great *** tackle this challenge,we trained neural network potentials(nnP)with the Schnet architecture on a structurally diverse database of density functional theory(DFT)*** database was iteratively extended by active learning to cover not only low-energy equilibrium configurations but also high-energy transition *** demonstrate that the resulting reactive nnPs retain DFT accuracy for thermodynamic stabilities,vibrational properties,as well as reactive and non-reactive phase *** a showcase,we screened an existing zeolite database and revealed>20k additional hypothetical frameworks in the thermodynamically accessible range of zeolite ***,our nnPs are expected to be essential for future high-throughput studies on the structure and reactivity of siliceous zeolites.

关键词： synthesis zeolite zeolites

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Comparative analysis of clinicopathological correlations of cyclooxygenase-2 expression in resectable pancreatic cancer

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World Journal of Gastroenterology 2010年第15期16卷 1879-1884页

作者： Marketa Hermanova petr Karasek Jiri Tomasek Jiri Lenz Jiri Jarkovsky petr Dite First Department of Pathologic Anatomy Medical Faculty of Masaryk University St. Anne’s University Hospital Department of Complex Oncology Care Masaryk Memorial Cancer Institute Institute of Biostatistics and Analyses Masaryk University Department of Gastroenterology Medical Faculty of Masaryk University and The Faculty Hospital Brno

AIM:To perform a comparative analysis of clinicopathological correlations of cyclooxygenase2 (COX2) expression in pancreatic cancer, examined by monoclonal and polyclonal ***: The COX2 expression in 85 resection specimens of pancreatic ductal adenocarcinoma was immunohistochemically examined using both monoclonal and polyclonal antibodies. The final immunoscores were obtained by multiplying the percentage of positive cells with the numeric score reflecting the staining ***2 expression levels were classified into three categories (0, 1+, and 2+) and the clinicopathological correlations were statistically evaluated and ***: The positive tumor expression rates of COX2 were 80.5% using monoclonal antibody and 69.4% using polyclonal antibody. In the KaplanMeier analysis, no significant correlations were found between levels of COX2 expression and overall survival (OS), but trends to longer OS were found in COX2 negative cases using monoclonal antibody. Significantly longer disease free survival was revealed in COX2 negative cases using monoclonal antibody (P = 0.019). no correlations between COX2 expression levels and grade (G), tumor (T) status and nodal (n) status were demonstrated. Low histological grade showed a strong association with a longer OS (P n of survival and T status revealed a shorter OS in T3 tumors, but the results reached only marginal statistical significance (P = 0.070). In the multivariate Cox proportional hazards regression model, histological grade, T and n status remained valuable predictors of a worse survival with borderline significance for T [hazards ratio (HR) = 4.18 for G (if G = 3, P n (if n = 1, P = 0.006)]. Higher grade, T or n status was associated with a worse OS. COnCLUSIOn: The immunohistochemically assessed level of COX2 expression does not seem to represent a valuable independent prognostic factor and is not super

关键词： Pancreatic cancer Cyclooxygenase2 Immunohistochemistry Monoclonal antibody Polyclonal antibody

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Analysis of the instability growth rate during the jet-background interaction in a magnetic field

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Research in Astronomy and Astrophysics 2013年第6期13卷 687-694页

作者： Miroslav Horky petr Kulhnek Czech Technical University in Prague Faculty of Electrical Engineering Department of PhysicsTechnick 2166 27 Prague Czech Republic Astronomical Institute of the Academy of Sciences of the Czech Republic Bocn' Ⅱ 1401/1a 141 31 Prague 4 Czech Republic

The two-stream instability is common, responsible for many observed phe- nomena in nature, especially the interaction of jets of various origins with the back- ground plasma （e.g. extragalactic jet interacting with the cosmic background）. The dispersion relation that does not consider magnetic fields is described by the well- known Buneman relation. In 2011, Bohata, Bren and Kulhanek derived the relation for the two-stream instability without the cold limit, with the general orientation of a magnetic field, and arbitrary stream directions. The maximum value of the imaginary part of the individual dispersion branches ωn（k） is of interest from a physical point of view. It represents the instability growth rate which is responsible for the onset of turbulence mode and subsequent reconnection on the scale of the ion radius accom- panied by a strong plasma thermalization. The paper presented here is focused on the non-relativistic instability growth rate and its dependence on various input parameters, such as magnitude and direction of magnetic field, sound velocity, plasma frequency of the jet and direction of the wave vector during the jet - intergalactic medium in- teraction. The results are presented in plots and can be used for determination of the plasma parameter values close to which the strong energy transfer and thermalization between the jet and the background plasma occur.

关键词： plasmas -- methods: numerical -- instabilities -- turbulence -- waves-- MHD

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Application of comprehensive two-dimensional gas chromatography with masss pectrometric detection for the analysis of selected drug residues in wastewater and surface water

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Journal of Environmental Sciences 2013年第1期25卷 204-212页

作者： petr Lacina Ludmila Mravcov Milada Vvrov Institute of Chemistry and Technology of Environmental Protection Faculty of ChemistryBrno University of Technology Geotest a.s.Smahova 1244/112Brno 62700Czech Republic

Pharmaceutical residues have become tightly controlled environmental contaminants in recent years, due to their increasing concentration in environmental components. This is mainly caused by their high level of production and everyday consumption. Therefore there is a need to apply new and sufficiently sensitive analytical methods, which can detect the presence of these contaminants even in very low concentrations. This study is focused on the application of a reliable analytical method for the analysis of 10 selected drug residues, mainly from the group of non-steroidal anti-inflammatory drugs （salicylic acid, acetylsalicylic acid, ctofibric acid, ibuprofen, acetaminophen, caffeine, naproxen, mefenamic acid, ketoprofen, and dicofenac）, in wastewaters and surface waters. This analytical method is based on solid phase extraction, derivatization by n-methyl-n-（trimethylsilyl）trifluoroacetamide （MSTFA） and finally analysis by comprehensive two-dimensional gas chromatography with Time-of-Flight mass spectrometric detection （GC×GC- TOF MS）. Detection limits ranged from 0.18 to 5 ng/L depending on the compound and selected matrix. The method was successfully applied for detection of the presence of selected pharmaceuticals in the Svratka River and in wastewater from the wastewater treatment plant in Brno-Modrice, Czech Republic. The concentration of pharmaceuticals varied from one to several hundreds of ng/L in surface water and from one to several tens of μg/L in wastewater.

关键词： non-steroidal anti-inflammatory drugs solid phase extraction derivatization comprehensive two-dimensional gaschromatography surface water wastewater

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Amorphous Ge-Sb-Se-Te chalcogenide films fabrication for potential environmental sensing and nonlinear photonics

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Journal of Materiomics 2022年第5期8卷 1009-1019页

作者： Tomas Halenkovic Marion Baillieul Jan Gutwirth petr nemec Virginie nazabal Department of Graphic Arts and Photophysics Faculty of Chemical TechnologyUniversity of PardubiceStudentska 57353210PardubiceCzech Republic Univ Rennes CNRSISCR(Institut des Sciences Chimiques de Rennes)e UMR 6226F-35000RennesFrance

Quaternary Ge-Sb-Se-Te chalcogenide thin films were fabricated by rf magnetron sputtering from Ge_(19)Sb_(17)Se_(64-x)Te_(x)(x=5,10,15,20)sputtering targets in order to select appropriate compositions for infrared sensor and optical nonlinear *** influence of chemical composition and deposition parameters on the optical properties,structure and wettability was thus *** amorphous thin films seem to be constituted by selenide entities that can include tellurium atoms in variable proportion such as[GeSe_(4-x)Te_(x)]and[SbSe_(3-x)Te_(x)](x=0,1,2)and Ge(Sb)-Ge(Sb)bonds according to Raman *** angle measurements of the thin films showed values of 68e71for water and their surface energies in the range of~36e39 mJ$m-2 seem suitable for surface functionalization required for photonic sensor ***,the maximum nonlinearity at the telecom wavelength with respect to the highest figure of merit value was found for the thin film with composition Ge_(19)Sb_(17)Se56Te8 having nonlinear refractive index of 28×10^(-18) m2·W^(-1).Due to their low optical bandgap energies,they may find their full interest for nonlinear optics in the mid-infrared *** IR transparency in combination with high(non)linear refractive indices make these materials attractive in the field of midIR sensing and optical nonlinear devices.

关键词： Chalcogenide Thin films Glass Amorphous Optical properties nLO Contact angles Sputtering Raman

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Forces of RBC interaction with single endothelial cells in stationary conditions:Measurements with laser tweezers

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Journal of Innovative Optical Health Sciences 2021年第5期4卷 53-63页

作者： Arseniy A.Kapkov Alexey n.Semenov petr B.Ermolinskiy Andrei E.Lugovtsov Alexander V.Priezzhev Faculty of Physics Lomonosov Moscow State UniversityLeninskie GoryMoscow 119991Russia Faculty of Biology Lomonosov Moscow State UniversityLeninskie GoryMoscow 119991Russia

Red blood cells(RBCs)are able to interact and communicate with endothelial cells(ECs).Under some pathological or even normal conditions,the adhesion of RBCs to the endothelium can be ***,the mechanisms and many aspects of the interaction between RBCs and ECs are not fully *** this work,we considered the interaction of single RBCs with single ECs in vitro aiming to quantitatively determine the force of this interaction using laser *** were performed under different concentrations of proaggregant macromolecules and in the presence or absence of tumor necrosis factor(TnF-α)activating the *** have shown that the strength of interaction depends on the concentration of fibrinogen or dextran proaggregant macromolecules in the environment.A nonlinear increase in the force of cells interaction(from 0.4 pn to 21 pn)was observed along with an increase in the fibrinogen con-centration(from 3 mg/mL to 9 mg/mL)in blood plasma,as well as with the addition of dextran macromolecules(from 10 mg/mL to 60 mg/mL).Dextran with a higher molecular mass(500 kDa)enhances the adhesion of RBCs to ECs greater compared to the dextran with a lower molecular mass(70 kDa).With the preliminary activation of ECs with TnF-α,the force of interaction ***,the adhesion of echinocytes to EC compared to discocytes is significantly *** results may help to better understand the process of interaction between RBCs and ECs.

关键词： Endothelial cells red blood cells laser tweezers adhesion

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