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Significant decrease in prevalence ofHelicobacter pylori in the Czech Republic

World Journal of Gastroenterology 2012年第32期18卷 4412-4418页

作者： Jan Bure marcela kopáová Ilona Koupil Bohumil Seifert Miluka kodová Fendrichová Jana pirková Viktor Voíek Stanislav Rejchrt TomáDouda Norbert Král Ilja Tachecí Second Department of Medicine Gastroenterology Charles University in PrahaFaculty of Medicine at Hradec KrálovéUniversity Teaching Hospital50005 Hradec KrálovéCzech Republic Centre for Health Equity Studies Karolinska InstituteStockholm University17177 StockholmSweden First Faculty of Medicine Institute of General PracticeCharles University12108 PrahaCzech Republic Institute of Clinical Biochemistry and Diagnostics Charles University in PrahaFaculty of Medicine at Hradec KrálovéUniversity Teaching Hospital50005 Hradec KrálovéCzech Republic

AIM:To study possible decrease in prevalence of Helicobacter pylori(***) infection in the Czech Republic within a 10-year ***:A total of 22 centres entered the *** catchment areas of these centres covered cities and towns with more than 20 000 inhabitants,smaller towns(≤ 20 000 inhabitants) with surrounding villages and rural areas,and were spread over the whole country,corresponding well to the geographical distribution of the Czech population.A total of 1 837 subjects(aged 5-98 years) took part in the study,randomly selected out of 38 147 people from the general *** infection was investigated by means of a 13 C-urea breath *** samples in duplicates were analysed using isotope ratio mass *** cut-off point was *** and demographic characteristics were based on data from self-completed ***:The overall prevalence of *** infection was 23.5%(430/1826),and 4.8%(20/420) in children aged 15 or *** was no statistically significant difference in prevalence between males(24.3%;208/857) and females(22.9%,222/969,P = 0.494).*** infection was strongly associated with higher age,among subjects aged 55+ years,prevalence of *** infection was 39.8%(252/633,P < 0.001).The highest prevalence of *** infection was found among persons aged 55-64 years(43.9%,97/221) and 75+ years(37.9%,58/153).Among study subjects aged 15+ years,prevalence of *** infection was significantly increased in those with lowest education(odds risk 3.19,95% CI 1.87-5.47).Compared to never married(14.1%),the prevalence of *** infection was statistically significantly higher among married(35.4%,246/694,P < 0.001),divorced(36.8%,49/133,P < 0.001) and widowed study subjects(40.2%,45/112,P < 0.001),both in minimally and fully adjusted *** was no significant difference in the prevalence of *** infection between married and widowed subjects(35.4%,246/694 vs 40.2%,45/112,P = 0.389).Ther

关键词： Epidemiology Helicobacter pylori Czech Republic 13 C-urea breath test Decline of prevalence

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Advantageous mechanochemical synthesis of copper(Ⅰ)selenide semiconductor,characterization,and properties

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Frontiers of Chemical Science and Engineering 2022年第3期16卷 433-442页

作者： Katarína Gáborová marcela Achimovičová Michal Hegedüs Vladimír Girman Mária Kaňuchová Erika Dutková Institute of Geotechnics Slovak Academy of SciencesKošice04001Slovakia Institute of Metallurgy Faculty of MaterialsMetallurgy and RecyclingTechnical UniversityKošice04201Slovakia Synthon s.r.o.Blansko67801Czech Republic Faculty of Science Pavol JozefŠafárik UniversityKošice04154Slovakia Institute of Earth Resources Faculty of MiningEcologyProcess Control and GeotechnologiesTechnical UniversityKošice04200Slovakia

Copper(I)selenide-nanocrystalline semiconductor was synthesized via one-step mechanochemical synthesis after 5 min milling in a planetary ball *** kinetics of synthesis was followed by X-ray powder diffraction analysis and specific surface area measurements of milled 2Cu/Se *** X-ray diffraction confirmed the orthorhombic crystal structure of Cu_(2)Se with the crystallite size∼25 *** surface chemical structure was studied by X-ray photoelectron spectroscopy,whereby the binding energy of the Cu 2p and Se 3d signals corresponded to Cu^(+)and Se^(2−)oxidation *** electron microscopy revealed agglomerated nanocrystals and confirmed their orthorhombic structure,as *** optical properties were studied utilizing ultraviolet-visible spectroscopy and photoluminescence *** direct bandgap energy 3.7 eV indicated a blue-shift phenomenon due to the quantum size *** type of Cu_(2)Se synthesis can be easily adapted to production dimensions using an industrial vibratory *** advantages of mechanochemical synthesis represent the potential for inexpensive,environmentally-friendly,and waste-free manufacturing of Cu_(2)Se.

关键词： Cu_(2)Se berzelianite nanocrystalline semiconductor mechanochemical synthesis planetary ball mill

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Analysis of the microbial communities in soils of different ages following volcanic eruptions

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Pedosphere 2020年第1期30卷 126-134页

作者： marcela HERNáNDEZ marcela CALABI Ralf CONRAD Marc G.DUMONT Max Planck Institute for Terrestrial Microbiology Karl-von-Frisch-Str.10Marburg 35043(Germany) Scientific and Technological Bioresource Nucleus Universidad de La FronteraTemuco(Chile) School of Biological Sciences University of SouthamptonSouthampton SO171BJ(UK)

Volcanism is a primary process of land *** provides a model for understanding soil-forming processes and the role of pioneer bacteria and/or archaea as early colonizers in those new *** objective of this study was to identify the microbial communities involved in soil *** was extracted from soil samples from the Llaima volcano in Chile at sites destroyed by lava in different centuries(1640,1751,and 1957).Bacterial and archaeal 16 S r RNA genes were analyzed using quantitative polymerase chain reaction(q PCR)and Illumina Mi Seq *** showed that microbial diversity increased with soil age,particularly between the 1751 and 1640 *** archaeal communities,Thaumarchaeota was detected in similar abundances in all soils,but Euryarchaeota was rare in the older *** analysis of bacterial 16 S r RNA genes showed high abundances of Chloroflexi(37%),Planctomycetes(18%),and Verrucomicrobia(10%)in the youngest *** and Acidobacteria were highly abundant in the older soils(16%in 1640 and 15%in 1751 for Acidobacteria;38%in 1640 and 27%in 1751 for Proteobacteria).The microbial profiles in the youngest soils were unusual,with a high abundance of bacteria belonging to the order Ktedonobacterales(Chloroflexi)in the 1957 soil(37%)compared with the 1751(18%)and 1640(7%)*** this study,we show that there is a gradual establishment of the microbial community in volcanic soils following an eruption and that specific microbial groups can colonize during the early stages of recovery.

关键词： 16S rRNA gene extreme environment high-throughput sequencing Ktedonobacterales microbial diversity pioneer microbe recolonization soil formation volcanic deposit

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MnFe2O4 nanoparticles as new catalyst for oxidative degradation of phenol by peroxydisulfate

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Journal of Environmental Sciences 2017年第3期29卷 269-277页

作者： marcela Stoia Cornelia Muntean Bogdan Militaru Faculty of Industrial Chemistry and Environmental Engineering Politehnica University TimisoaraR0-300223 TimisoaraRomania Research Institute for Renewable Energy Politehnica University TimisoaraRO-300006TimisoaraRomania

Manganese ferrite nanopowder was prepared by thermal decomposition at 400℃ of the gel synthesized from manganese and iron nitrates and polyvinyl alcohol. X-ray diffractometry evidenced that manganese ferrite was formed as single crystalline phase at this temperature. Scanning electron microscope images evidenced the formation of very fine spherical particles （d 〈 11 nm） of manganese ferrite, with specific surface area of 147 m2/g. The powder obtained at 400℃ was used as a catalyst for the oxidative degradation of phenol in aqueous solutions, in the presence of potassium peroxydisulfate as oxidant. High phenol removal efficiencies above 90% were reached at： pH 3-3.5, phenol initial concentration around 50 mg/L, peroxydisulfate：phenol mass ratio 10：1, and catalyst dose 3 g/L. Total organic carbon measurements showed that the degradation of phenol goes, under these conditions, to mineralization in an extent of 60%.

关键词： Manganese ferriteNanoparticlesPhenolPeroxydisulfateCatalytic oxidation

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Impact Sensitivity in Respect of the Crystal Lattice Free Volume and the Characteristics of Plasticity of Some Nitramine Explosives

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含能材料 2015年第12期23卷 1186-1191页

作者： Svatopluk Zeman marcela JUNGov Qi-Long YAN Institute of Energetic Materials Faculty of Chemical TechnologyUniversity of Pardubice

The relationship between the crystal lattice free volume,ΔV,and impact sensitivity,E_(dr),of ten nitramines has been analyzed. It was found that this relationship is not uniquely determined,i. e. it is not given only by their own ΔV values but fundamentally by the type and intensity of the intermolecular forces in the nitramine crystals. Also,relationships between the E_(dr)values,on the one hand,and bulk modulus,K,and shear modulus,G,on the other,have been the subject of discussion not only for pure cyclic nitramines but also for their PBXs,bonded by a poly-fluoro binder. The closest linear correlation exists between the E_(dr)values and dimensionless K·G^(-1) ratio which indicates the plasticity range. A similar relationship is valid also for the ΔV values. Relationships of the E_(dr) and / or ΔV values with the shear modulus or to the K·G^(-1) ratio reflect an unusual behavior of ε-HNIW to which the published morphological instability of this particular HNIW version might also be related.

关键词：爆破器料含能材料烟火器材材料学

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Spontaneous bacterial peritonitis:A severe complication of liver cirrhosis

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World Journal of Gastroenterology 2009年第44期15卷 5505-5510页

作者： Jan Lata Oldich Stiburek marcela kopacova Department of Internal Medicine and Hepatogastroenterology University Hospital and Faculty of MedicineMasaryk University637 00 BrnoCzech Republic 2nd Department of Medicine Charles University in PrahaFaculty of Medicine at Hradec KraloveUniversity Teaching Hospital500 05 Hradec KráloveCzech Republic

This report presents a survey of current knowledge concerning one of the relatively frequent and severe complications of liver cirrhosis and associated ascites-spontaneous bacterial peritonitis. Epidemiology,aetiology... 详细信息

关键词： Liver cirrhosis Portal hypertension Ascites Spontaneous bacterial peritonitis

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Towards full predictions of temperature dynamics in McNary Dam forebay using OpenFOAM

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Water Science and Engineering 2013年第3期6卷 317-330页

作者： Yu-Shi WANG marcela POLITANO Ryan LAUGHERY IIHR-Hydroscience and Engineering The University of Iowa Iowa City U.S. Army Corps of Engineers Walla Walla District Walla Walla

Hydroelectric facilities impact water temperature; low velocities in a reservoir increase residence time and enhance heat exchange in surface layers. In this study, an unsteady three-dimensional model was developed to predict the temperatm＇e dynamics in the McNary Dam forebay. The model is based on the open-source code OpenFOAM. RANS equations with the Boussinesq approximation were used to solve the flow field. A： realizable k-ε model that accounts for the production of wind turbulence was developed. Solar radiation and convective heat transfer at the free surface were included. The result of the model was compared with the field data collected on August 18, 2004. Changes in diurnal stratification were adequately predicted by the model. Observed vertical and lateral temperature distributions were accurately captured. Results indicate that the model can be used as a numerical tool to assess structural and operational alternatives to reduce the forebay temperature.

关键词： three-dimensional numerical simulation," water temperature," reservoir," thermal dynamics OpenFOAM McNary Dam forebay

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Promising psyllium-based composite containing TiO2 nanoparticles as aspirin-carrier matrix

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Progress in Natural Science:Materials International 2014年第3期24卷 205-209页

作者： marcela-Corina Rosu Ioan Bratu National Institute for Research and Development of Isotopic and Molecular Technologies

Composite nanomaterials represent a new trend in the biomedical field. Coupling inorganic/organic constituents with non-toxicity/biocompatibility properties leads to develop the new systems having special characteristics that can be used in various bio-applications. This paper describes the preparation and characterization of psyllium-based composites containing TiO2 nanoparticles in order to develop new therapeutic strategies for aspirin drug delivery. The structural characteristics of obtained materials were investigated by FTIR spectroscopy. The UV–vis spectrophotometric analysis was performed to evaluate the aspirin release behavior under different pH conditions at 37 1C. Combining psyllium(as an excellent source of fiber) with TiO2 inorganic unit(as vehicle of aspirin) it was found that polymeric-TiO2networks have promising potential for controlled aspirin release as therapeutic agent.

关键词： Psyllium Titanium dioxide Aspirin In vitro release

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Measurements in Situ and Spectral Analysis of Wind Flow Effects on overhead Transmission Lines

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Sound & Vibration 2019年第4期53卷 161-175页

作者： Maciej Dutkiewicz marcela R.Machado UTP University of Science and Technology Bydgoszcz85-796Poland. University of Brasilia Brasilia70910-900Brazil.

In the paper an important issue of vibrations of the transmission line in real conditions was *** research was carried out by the authors of this paper taking into account the cross-section of the cable being in use on the transmission *** was performed for the modern ACSR high voltage transmission line with span of 213.0 *** purpose of the investigation was to analyze the vibrations of the power transmission line in the natural environment and compare with the results obtained in the numerical *** was performed for natural and wind excited *** numerical model was made using the Spectral Element *** the spectral model,for various parameters of stiffness,damping and tension force,the system response was checked and compared with the results of the accelerations obtained in the situ measurements.A frequency response functions(FRF)were *** credibility of the model was assessed through a validation process carried out by comparing graphical plots of FRF functions and numerical values expressing differences in acceleration amplitude(MSG),phase angle differences(PSG)and differences in acceleration and phase angle total(CSG)*** attention was paid to the hysteretic damping *** of the wave number was performed for changing of the tension force and section area of the *** next aspect constituting the purpose of this paper was to present the wide possibilities of modelling and simulation of slender conductors using the Spectral Element *** obtained results show very good accuracy in the range of both experimental measurements as well as simulation *** paper emphasizes the ease with which the sensitivity of the conductor and its response to changes in density of spectral mesh division,cable cross-section,tensile strength or material damping can be studied.

关键词： Transmission line Spectral Element Method frequency response function

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Sequential ultrasound-assisted extraction of pectin and phenolic compounds for the valorisation of ‘Granny Smith’ apple peel

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Food Bioscience 2022年第5期49卷 1166-1175页

作者： Esteban Villamil-Galindo Andrea marcela Piagentini Instituto de Tecnología de Alimentos-Facultad de Ingeniería Química-Universidad Nacional del Litoral Santiago del Estero 28293000Santa FeArgentina Consejo Nacional de Investigaciones Científicas y T´ecnicas(CONICET) Argentina

This study aims to evaluate the impact of the sequential extraction system for phenolic compounds and pectin from waste ‘Granny Smith’ apple peel using ultrasound. The effects of solvent, formic acid concentration (CFA), and the number of extraction steps on the content of individual and total phenolic compounds (TPC), total flavonoids, and antioxidant capacity, were determined. Then, pectin was obtained from apple peel before (BE) and after (AE) phenolic compounds extraction, using conventional (TR) or ultrasound-assisted procedures (US). The two-steps 80% Acetone (0% CFA) extraction system had the highest TPC (3.47 g GAE/Kg). Procyanidin B2 (0.03-0.77 g/kg) was the major phenolic compound extracted from ‘Granny Smith’ apple peel. AE pectin extraction yield (6.38% for US and 4.92% for TR) was higher than BE. Pectin obtained had 57-60% DE, 9.3-10.3% Methoxyl content, and 436-460 equivalent weight. Wasted apple peel is a great low-cost source of phenolic compounds and pectin. Furthermore, it is possible to achieve the highest yields of both compounds through appropriate extraction sequences (AE: phenolic compound extraction followed by pectin extraction) and alternative technologies like ultrasound-assisted extraction.

关键词： Fruit waste by-products Circular economy Bioactive compounds Cavitation Procyanidins Antioxidants

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