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Silver fir tree-ring fluctuations decrease from north to south latitude—total solar irradiance and NAO are indicated as the main influencing factors

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Forest Ecosystems 2023年第6期10卷 717-731页

作者： vaclav simůnek Anna Prokůpkova Zdenek Vacek Stanislav Vacek Jan Cukor Jirí Remes Vojtech Hajek Giuseppe D'Andrea Martin Salek Paola Nola Osvaldo Pericolo Sarka Holzbachova Francesco Ripullone Faculty of Forestry and Wood Sciences Czech University of Life Sciences PragueKamýcka 129CZ—16500Prague 6SuchdolCzech Republic Forestry and Game Management Research Institute v.v.iStrnady 13625202JílovisteCzech Republic Czech Academy of Sciences Institute of Vertebrate BiologyKvetna 860365BrnoCzech Republic Department of Earth and Environmental Sciences University of PaviaVia S.Epifanio 14I-27100PaviaItaly Forests of the Czech Republic SOEPremyslova 1106/19NovýHradec Kralove50008Hradec KraloveCzech Republic School of Agricultural Forestry and Environmental SciencesUniversity of BasilicataViale dell’Ateneo Lucano 10I-85100PotenzaItaly Faculty of Environmental Sciences Czech University of Life Sciences PragueKamýcka 129CZ—16500PragueSuchdolCzech Republic

Silver fir(Abies alba Mill.)is a flexible European tree species,mainly vegetating within the mountainous regions of Europe,but its growth responses across its latitudinal and longitudinal range have not yet been satisfactorily verified under changing environmental *** study describes the tree-ring increment of silver fir in research plots across a latitudinal gradient from the northern range in Czechia(CZ),through Croatia(HR)to the southernmost range in Italy(IT).The research aims to analyze in detail the dynamics and cyclicity of the ringwidth index(RWI)and how it relates to climatic factors(temperature and precipitation),the North Atlantic Oscillation(NAO),and total solar irradiance(TSI),including the determination of *** results show that the main drivers affecting fir growth are the seasonal NAO index and *** temperatures affect RWI early in the vegetation season,while lack of precipitation during the summer is a limiting factor for fir growth,especially in *** temperatures and temperatures in June and July negatively impact,while seasonal precipitation totals in the same months positively influence the RWI in all research plots across *** longest growth cycles in fir RWI were recorded in the northernmost studied plots in *** cyclical fluctuations recede approaching the *** cyclic increase in RWI is related to the TSI,which decreases its effect from north to *** TSI's effects vary,positively impacting CZ but negatively influencing HR while remaining relatively neutral in *** the other hand,seasonal NAO tends to negatively affect silver fir growth in HR and CZ but has a mildly positive effect in *** conclusion,the TSI and the influence of the seasonal NAO index are prevalent in the fir RWI and are accompanied by a greater cyclicity of RWI in Central Europe(temperature optimum)than in the Italian Mediterranean region,where this tree species is limited by climatic conditions,especially lack of pre

关键词： Abies alba Mill Tree-rings Solar cycle North Atlantic oscillation Precipitation Temperature

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Transonic Instability in Entrance Part of Mixing Chamber of High-Speed Ejector

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Journal of Thermal Science 2005年第3期14卷 258-263,271页

作者： vaclav Dvorak Pavel Safarik Technical University of Liberec Faculty of Mechanical Engineering Division of Power Engineering Halkova 6 461 17 Liberec Czech Republic Ph.DCzech Technical University in Prague Faculty of Mechanical Engineering 207- Institute of Fluid Dynamics and Power Engineering Division of Fluid Dynamics and Thermodynamics. Technicka 4 166 07 Praha 6 Czech Republic

The paper deals with experimental and numerical study of flow structure in two-dimensional model of supersonic ejector. Schlieren pictures of flow structure were taken, static pressure distributions on side wall were measured and Fluent software to calculate the flow structure in supersonic ejector was used. For certain region of back pressure ratio pb/p02 and stagnation pressure ratio of both streams p01/p02 the terminal shock wave is close to the trailing edge of the primary flow nozzle and a transonic instability occurs. The instability causes the movement of position of boundary layer separation, the structure of shock waves changes and all flow structure oscillates. The movie of these regimes during schlieren experiments was taken and relevant numerical modelling was performed.

关键词： transonic instability ejector shock waves

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Supersonic Flow Structure in the Entrance Part of a Mixing Chamber of 2D Model Ejector

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Journal of Thermal Science 2003年第4期12卷 344-349页

作者： vaclav Dvorak Pavel Safarik Technical University in Liberec Faculty of Mechanical Engineering Department of Power Engineering Equipment. Halkova 6461 17 Liberec Czech RepublicCzech Technical University in Prague Faculty of Mechanical Engineering 207.1 Institute of Fluid Dynamics and Power Engineering Division of Fluid Dynamics and Thermodynamics. Technicka 4 166 07 Praha 6 Czech Republic

The paper deals with experimental and numerical results of investigation into supersonic and transonic flow past a two-dimensional model ejector. Results of optical measurements show a flow structure and flow parameter development in the entrance part of the mixing chamber of the ejector. Numerical results are obtained by means of both the straight solution of shock waves in supersonic flow field using classical relations of parameters of shock waves and the Fluent 6 program. Results of numerical solutions are compared with experimental pictures of flow fields. Flow structure development in the mixing chamber is analysed in detail.

关键词： supersonic ejector shock waves shear layers mixing process boundary layer separation.

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Structural and photocatalytic characteristics of TiO_(2) coatings produced by various thermal spray techniques

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Journal of Advanced Ceramics 2013年第3期2卷 218-226页

作者： Pavel CTIBOR vaclav STENGL Zdenek PALA Institute of Plasma Physics ASCRv.v.i.Za Slovankou 3PragueCzech Republic Institute of Inorganic Chemistry ASCRv.v.i.Husinec-RezCzech Republic

Titanium dioxide(TiO_(2))was elaborated by four different thermal spray techniques-(i)plasma spraying using a water-stabilized torch,(ii)plasma spraying using a gas-stabilized torch,(iii)high velocity oxy-fuel gun,and(iv)oxy-acetylene *** porosity of the coatings was studied by optical microscopy,nano-structural features by scanning electron microscopy(SEM),phase composition by X-ray diffraction(XRD);the microhardness,surface roughness and wear resistance were *** diffuse reflectance was measured by ultra-violet/visible/near-infrared(UV/Vis/NIR)scanning *** kinetics of photocatalytic degradation of gaseous acetone was measured under a UV lamp with 365 nm *** all the applied spray processes,the transformation of anatase phase from the initial powders to rutile phase in the coatings *** spite of this transformation,all the coatings exhibited certain photocatalytic activity,which correlated well with their band gap energy calculated from *** the coatings offer relatively good mechanical properties and can serve as robust photocatalysts.

关键词： plasma spraying high velocity oxy-fuel(HVOF)spraying flame spraying titanium dioxide(TiO_(2)) photocatalysis band gap

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Analysis of 3.4 Ah lithium-sulfur pouch cells by electrochemical impedance spectroscopy

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Journal of Energy Chemistry 2022年第9期31卷 318-325,I0009页

作者： Dominika Capkova vaclav Knap Andrea Strakova Fedorkova Daniel-Ioan Stroe Department of Physical Chemistry Pavol Jozef Safarik University in KosiceKosice 04154Slovak Republic Faculty of Electrical Engineering Czech Technical University in PraguePrague 16627Czech Republic Department of Energy Technology Aalborg UniversityAalborg East 9220Denmark

Despite great progress in lithium-sulfur(Li-S) batteries, the electrochemical reactions in the cell are not yet fully understood. Electrode processes, complex interfaces and internal resistance may be characterized by electrochemical impedance spectroscopy(EIS). EIS is a non-destructive technique and easy to apply, though there are challenges in ensuring the reproducibility of measurements and the interpretation of impedance data. Here, we present the impedance behavior of a 3.4 Ah Li-S pouch cell characterized by EIS. The impedance changes were analyzed over the entire depth-of-discharge, depth-of-charge,and at various temperatures. Based on the formation of intermediates during(dis)charging, the changes of resistances are observed. Overall, the increase in temperature causes a decrease in electrolyte viscosity,lowering the surface energy which can improve the penetration of the electrolyte into the electrode pores. Moreover, the effect of superimposed AC current during EIS measurement was analyzed, and the results show the dependence of the charge transfer resistance on superimposed AC current which was lower compared to steady-state conditions and consents with theory.

关键词： Lithium-sulfur battery Impedance Equivalent circuit Temperature dependencies Charging/discharging differences Dynamic electrochemical impedance spectroscopy

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Optimized Deep Learning-Inspired Model for the Diagnosis and Prediction of COVID-19

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Computers, Materials & Continua 2021年第5期67卷 2353-2371页

作者： Sally M.Elghamrawy Aboul Ella Hassnien vaclav Snasel MISR Higher Institute for Engineering and Technology MansouraEgypt Faculty of Computers and Information Cairo UniversityCairoEgypt VSB-Technical University of Ostrava Czech Republic

Detecting COVID-19 cases as early as possible became a critical issue that must be addressed to avoid the pandemic’s additional spread and early provide the appropriate treatment to the affected *** study aimed to develop a COVID-19 diagnosis and prediction(AIMDP)model that could identify patients with COVID-19 and distinguish it from other viral pneumonia signs detected in chest computed tomography(CT)*** proposed system uses convolutional neural networks(CNNs)as a deep learning technology to process hundreds of CT chest scan images and speeds up COVID-19 case prediction to facilitate its *** employed the whale optimization algorithm(WOA)to select the most relevant patient signs.A set of experiments validated AIMDP *** demonstrated the superiority of AIMDP in terms of the area under the curve-receiver operating characteristic(AUC-ROC)curve,positive predictive value(PPV),negative predictive rate(NPR)and negative predictive value(NPV).AIMDP was applied to a dataset of hundreds of real data and CT images,and it was found to achieve 96%AUC for diagnosing COVID-19 and 98%for overall *** results showed the promising performance of AIMDP for diagnosing COVID-19 when compared to other recent diagnosing and predicting models.

关键词： Convolutional neural networks coronavirus disease 2019(COVID-19) CT chest scan imaging deep learning technique feature selection whale optimization algorithm

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Sensitivity of polyphagous(Plodia interpunctella)and stenophagous(Ephestia kuehniella)storage moths to residual insecticides:effect of formulation and larval age

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Insect Science 2021年第6期28卷 1734-1744页

作者： vaclav Stejskal Jitka Stara Stano Pekar Marta Nesvorna Jan Hubert Crop Research Institute PragueCzechia Faculty of Science Department of Botany and ZoologyMasaryk UniversityBrnoCzechia Faculty of Agrobiology Food and Natural ResourcesCzech University of Life SciencesPragueCzechia

Pyralid moths,Ephestia kuehniella and Plodia interpunctella,are prevalent stored product *** insecticides are the main tool to control these moths in the *** data describing the response of these moths to insecticides are *** lethal effect of the organophosphate,pyrethroid,and halogenated-pyrrole on moths larvae were compared in laboratory *** hypothesis was that the very polyphagous ***-punctella would have generally higher insecticide tolerance than that of the stenophagous *** insecticide concentrations were applied onto the inner surface of glass tube *** larvae of 14 or 21 d old of *** and 7 or 14 d old of *** were used by *** larval mortality was checked after 24 h of *** mortality was significantly influenced by age of larvae and the groups of *** differences among the efficacies of the tested formulations with identical active compounds were found,except significant different mortality of *** on deltamethrin formulations.A comparison of analytical standards showed that *** was less susceptible to the active ingredient pirimiphos-methyl than ***,while *** was less susceptible to deltamethrin than *** differences between the two species were observed for *** therefore rejected the hypothesis that polyphagy/stenophagy can be a general predictor of insecticide tolerance in the two tested storage *** most important finding for effective use was that the young larvae of both species were more susceptible to tested insecticides than older larvae.

关键词： efficacy integrated pest management IRAC pesticides Pyralidae residual

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Differential levels of mite infestation of wheat and barley in Czech grain stores

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Insect Science 2009年第3期16卷 255-262页

作者： Jan Hubert Zuzana Kucerova Radek Aulicky Marta Nesvorna vaclav Stejskal Crop Research Institute Prague Czech Republic

While mites are able to utilize numerous food sources, the suitability of the food strongly influences population growth. The different suitabilities of various stored agricultural products will thus affect the level of infestation. In this study, we compared field mite infestation rates in two stored cereals： wheat and barley. We analyzed mite abundance, frequency and species composition in samples of grain obtained from 79 selected Czech grain stores. Stored barley seemed to be more vulnerable to mite attack than wheat, as we consistently found more infested samples, more species and higher mean and median mite abundance per sample in barley as compared to wheat. The mean mite abundance per sam- ple were 55 and 506 individuals for wheat and barley, respectively. In barley, 10% of sampies exceeded allergen risk threshold （i.e., 1 000 individuals per kg of grain）. Altogether, 25 species were identified from approximately 35 000 individuals. The most frequently identified species were the same in wheat and barley, that is, Tydeus interruptus Sig Thor, Acarus siro L., Tarsonemus granarius Lindquist, Lepidoglyphus destructor （Schrank） and Tyrophagus putrescentiae （Schrank）. Based on principal components analysis, we found a closer association of T. interruptus, T. putrescentiae, L. destructor and Cheyletus eruditus （Schrank） with barley samples, corresponding to the high frequency and abundance values of these mites. The probable reasons for the higher infestation, especially mite abundance in barley, are discussed in relation to the higher proportion of crushed parts, which may release favorable nutrient sources and amplify the abundance values.

关键词： barley food grain mite storage wheat

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Endometriosis and ovarian cancer

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World Journal of Clinical Oncology 2014年第5期5卷 800-805页

作者： Milena Králí?ková vaclav Vetvicka Department of Histology and Embryology Faculty of Medicine Charles University Plzen CZ-301 00 Czech Republic Department of Obstetrics and Gynecology University Hospital Faculty of Medicine Charles University Plzen CZ-301 66 Czech Republic Biomedical Centre Faculty of Medicine in Plzen Charles University Plzen CZ-301 66 Czech Republic Department of Pathology University of Louisville Louisville KY 40202 United States

Endometriosis is the leading cause of morbidity among premenopausal women and the complex pathogenesis of this disease remains controversial despite extensive research. This disease represents one of the most common gynecological problems. It is generally believed that this disease is due primarily to retrograde menstruation or transplantation of shed endometrium. Based on overwhelming data, ovarian endometrioma is considered a neoplastic process, since most endometriosis-associated ovarian carcinoma occur in the presence of atypical ovarian endometriosis. A study comparing patients with typical epithelial ovarian cancer with endometriosis-associated ovarian cancer demonstrated that the patients with the latter disease strongly differ in both biological and histological characteristics. The prevelance of this disease is not completely established, but approximately 15 percent of women suffer from this disease. In addition, we know about the possible links between endometriosis and cancer for almost 100 years. Despite clear evidence revealing that endometriosis increases ovariancancer risks, it is possible that it may not affect disease progression after the appearance of ovarian cancer. However, despite clear evidence revealing that endometriosis increases ovarian cancer risk, our knowledge of the risk factors is far from established. In our review, we focused on the most recent approaches including possible biomarkers and genetic approaches.

关键词： Endometriosis Ovarian cancer Biomarkers Cancer Histology

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Enhancements of SDR-Based FPGA System for V2X-VLC Communications

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Computers, Materials & Continua 2021年第9期68卷 3629-3652页

作者： Lukas Danys Radek Martinek Rene Jaros Jan Baros Petr simonik vaclav Snasel Department of Cybernetics and Biomedical Engineering Faculty of Electrical Engineering and Computer ScienceVSB–Technical University of OstravaOstrava-Poruba70800Czechia Department of Electronics Faculty of Electrical Engineering and Computer ScienceVSB–Technical University of OstravaOstrava-Poruba70800Czechia Department of Computer Science Faculty of Electrical Engineering and Computer ScienceVSB–Technical University of OstravaOstrava-Poruba70800Czechia

This pilot study focuses on a real measurements and enhancements of a software defined radio-based system for vehicle-to everything visible light communication(SDR-V2X-VLC).The presented system is based on a novel adaptive optimization of the feed-forward software defined equalization(FFSDE)methods of the least mean squares(LMS),normalized LMS(NLMS)and QR decomposition-based recursive least squares(QR-RLS)*** parameters of adaptive equalizations are adjusted in real-time to reach the best possible *** were carried out on a conventional LED Octavia III taillight drafted directly from production line and universal software radio peripherals(USRP)from National *** transmitting/receiving elements used multistate quadrature amplitude modulation(M-QAM)implemented in LabVIEW programming *** results were verified based on bit error ratio(BER),error vector magnitude(EVM)and modulation error ratio(MER).Experimental results of the pilot study unambiguously confirmed the effectiveness of the proposed solution(longer effective communication range,higher immunity to interference,deployment of higher state QAM modulation formats,higher transmission speeds etc.),as the adaptive equalization significantly improved BER,MER and EVM *** best results were achieved using the QR-RLS *** results measured on deployed QR-RLS algorithm had significantly better Eb/N0(improved by approx.20 dB)and BER values(difference by up to two orders of magnitude).

关键词： 5G feed-forward software defined equalization multistate quadrature amplitude modulation software defined radio visible light communication

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