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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 ce 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 ced(36.8%,49/133,P cts(40.2%,45/112,P cant 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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FeH_(x)的稳定性以及氢在地球核-幔边界的传输

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Science Bulletin 2023年第14期68卷 1567-1573,M0004页

作者：何宇 Duck Young Kim viktor V.Struzhkin Zachary M.Geballe Vitali Prakapenka 毛河光 Key Laboratory of High-Temperature and High-Pressure Study of the Earth’s Interior Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China center for High Pressure Science and Technology Advanced Research Shanghai 201203China Division of Advanced Nuclear Engineering Pohang University of Science and TechnologyPohang 37673Republic of Korea Geophysical Laboratory Carnegie InstitutionWashington DC 20015USA center for Advanced Radiation Sources University of ChicagoChicago IL 60637USA

地球内部水和铁的反应可以生成铁-氢合金.研究铁-氢合金可以增进对地球内部氢传输的认知.我们通过高压实验和第一性原理计算的方法,对高温高压下具有面心立方结构(fcc)FeH_(x)(x≤1)的相稳定性、密度、氢的输运性质和熔点进行了系统研究... 详细信息

地球内部水和铁的反应可以生成铁-氢合金.研究铁-氢合金可以增进对地球内部氢传输的认知.我们通过高压实验和第一性原理计算的方法,对高温高压下具有面心立方结构(fcc)FeH_(x)(x≤1)的相稳定性、密度、氢的输运性质和熔点进行了系统研究,证实了FeH_(x)在165 GPa时的稳定性.通过高温的分子动力学模拟,发现FeH_(x)在下地幔温压下转变为超离子态.在超离子态FeH_(x)中,氢离子快速扩散表现出类似流体的性质,扩散系数高达3.710^(-4)cm~2s^(-1).与超离子态冰类似,氢离子的快速扩散可以导致体系的熵增,使其的熔化温度增加.FeH_(x)可以将氢从地幔传输到外地核,使得外核成为H的潜在储库,并在核-幔边界上方留下了富氧的块状结构.

关键词：离子态第一性原理计算氢离子相稳定性地球内部熔化温度高压实验分子动力学模拟

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Separation of Molybdenum Isotopes at Supercritical Fluid Extraction with carbon Dioxide in a Vertical Gradient Field of Temperatures

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Open Journal of Metal 2020年第1期10卷 1-15页

作者： Boris viktorovich Borts Stella Fedorovna Skoromnaya viktor Ivanovich Tkachenко NSc Kharkov Institute of Physics and Technology NAS of Ukraine Kharkov Ukraine V. N. Karazin Kharkiv National University Kharkov Ukraine

Separation of molybdenum isotope complexes by supercritical fluid extraction (SFE) with carbon dioxide was studied experimentally. The extraction of molybdenum isotope complexes was carried out in the updated extraction chamber (reactor) of the SFE-U installation, which provided an initial pressure of P ≤ 20 MPa at constant temperatures of the upper T1 = 35°c and bottom T2 = 45°c flanges. The device, through which the eluent was discharged, involved a set of four thin tubes of different lengths located inside the reactor. The axes of the tubes and the reactor are parallel and the tubes are equally spaced circumferentially inside the reactor. The extract was removed from each tube through channels isolated from each other and located in the bottom flange with cylindrical expansion, in which several layers of filter paper were placed. After passing through the filters the extract entered a restrictor designed to remove the eluent from the reactor. The initial pressure of carbon dioxide and the holding time of the extract were specified in the experiments. The level of the eluent sampling was set by the lengths of the tubes depending on the reactor height. A method of producing molybdenum complexes was described. It was experimentally shown that at an initial pressure of 20 MPa and a given holding time a difference from the natural content of Mo isotopes for given heights of extract sampling depending on the reactor height was observed in extracts removed through filters. The ranges of deviation of the content of molybdenum isotopes in extracts from natural one were determined.

关键词： carbon Dioxide Supercritical Fluids Extraction Molybdenum Isotopes Separation

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Development and characterization of Eco-Friendly Non-Isocyanate Urethane Monomer from Jatropha curcas Oil for Wood composite Applications

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Journal of Renewable Materials 2023年第1期11卷 41-59页

作者： Samsul Bhakri Muhammad Ghozali Edy cahyono Evi Triwulandari Witta Kartika Restu Nissa Nurfajrin Solihat Apri Heri Iswanto Petar Antov viktor Savov Lee Seng Hua ErikaAyu Agustiany Lubos Kristak Widya Fatriasari Department of chemistry Universitas Negeri SemarangSemarang50229Indonesia Research center for chemistry National Research and Innovation Agency(BRIN)Serpong15314Indonesia Research center for Biomass and Bioproducts National Research and Innovation Agency(BRIN)Cibinong16911Indonesia Department of Forest Product Faculty of ForestryUniversitas Sumatera UtaraMedan20155Indonesia JATI-Sumatran Forestry Analysis Study center Medan20155Indonesia Faculty of Forest Industry University of ForestrySofia1797Bulgaria Laboratory of Biopolymer and Derivatives Institute of Tropical Forestry and Forest ProductUniversiti Putra MalaysiaSelangor43400Malaysia Department of Forest Products Faculty of Forestry and EnvironmentIPB UniversityBogor16680Indonesia Faculty of Wood Sciences and Technology Technical University in ZvolenZvolen96001Slovakia

The aim of this research work was to evaluate the potential of using renewable natural feedstock,i.e.,Jatropha curcas oil(JcO)for the synthesis of non-isocyanate polyurethane(NIPU)resin for wood composite *** polyurethane(PU)is synthesized through a polycondensation reaction between isocyanate and ***,utilizing toxic and unsustainable isocyanates for obtaining PU could contribute to negative impacts on the environment and human ***,the development of PU from eco-friendly and sustainable resources without the isocyanate route is *** this work,tetra-n-butyl ammonium bromide was used as the activator to open the epoxy ring with 3-Aminopropyltriethoxisylane as a catalyst to yield urethane of JcO(UJcO).The UJcO were characterized by Fourier Transform Infra-Red spectroscopy(FTIR)and their oxirane,and hydroxyl values were *** result showed that a decrease in oxirane value was found while the hydroxyl value was increased during the time,confirming that the urethane group was *** presence of functional groups in FTIR spectra at wave numbers 1732.08,1562.34,and 3348.42 cm^(−1) indicates the functional groups of c=O(urethane carbonyl),–NH,and–OH,respectively confirmed this *** potential applications of NIPU in the wood composite were also outlined.

关键词： Jatropha curcas oil urethane groups non-isocyanate polyurethane epoxidized JcO cyclic carbonate oxirane value wood composites

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A multi-mode super-fano mechanism for enhanced third harmonic generation in silicon metasurfaces

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Light(Science & Applications) 2023年第5期12卷 847-854页

作者： David Hahnel christian Golla Maximilian Albert Thomas Zentgraf viktor Myroshnychenko Jens Forstner cedrik Meier Theoretical Electrical Engineering&ceOPP Paderborn University33098 PaderbornGermany Physics Department&ceOPP Paderborn University33098 PaderbornGermany

We present strong enhancement of third harmonic generation in an amorphous silicon metasurface consisting of elliptical nano *** show that this enhancement originates from a new type of multi-mode Fano ***‘Super-Fano’resonances are investigated numerically in great detail using full-wave *** theoretically predicted behavior of the metasurface is experimentally verified by linear and nonlinear transmission ***,quantitative nonlinear measurements are performed,in which an absolute conversion efficiency as high as η_(max)≈2.8×10^(-7) a peak power intensity of 1.2 GW cm^(-2) is *** to an unpatterned silicon film of the same thickness amplification factors of up to ~900 are *** results pave the way to exploiting a strong Fano-type multi-mode coupling in metasurfaces for high THG in potential applications.

关键词： spectroscopy mechanism harmonic

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Multipotent stromal cells stimulate liver regeneration by influencing the macrophage polarization in rat

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World Journal of Hepatology 2018年第2期10卷 287-296页

作者： Andrey Elchaninov Timur Fatkhudinov Natalia Usman Irina Arutyunyan Andrey Makarov Anastasia Lokhonina Irina Eremina viktor Surovtsev Dmitry Goldshtein Galina Bolshakova Valeria Glinkina Gennady Sukhikh National Medical Research center for Obstetrics Gynecology and Perinatology named after Academician V.I.Kulakov of Ministry of Healthcare of Russian FederationMoscow 117997Russia Peoples Friendship University of Russia(RUDN University) Moscow 117198Russia Scientific Research Institute of Human Morphology Moscow 117418Russia Pirogov Russian National Research Medical University Ministry of Healthcare of the Russian FederationMoscow 117997Russia Research center of Medical Genetics Moscow 115478Russia

AIM To investigate the influence of the umbilical cordderived multipotent stromal cells(MScs) on recovery of the liver after the subtotal resection, that is, removal of 80% of the organ mass, a renowned model of the small-for-size liver remnant syndrome. METHODS The MScs were obtained from the intervascular tissue of umbilical cords, dissected from rat fetuses, by the explant culture technique. The vital labeling of MScs with РКН26 was carried out on the 3 rd passage. The subtotal resection was performed on male Sprague-Dawley rats. The experimental group animals received a transplant 106 MScs infused into the spleen. Hepatocyte proliferation was assessed by counting of either mitotic figures or Ki67-positive cells in microscopic images. MSc differentiation was assessed with antibodies to hepatocyte-specific marker cytokeratin 18(cK18), cholangiocyte-specific protein cK19, smooth muscle cell-specific protein α-SMA, the endothelial cell marker cD31, or the active fibroblast marker FAPα. Total macrophages of the liver were selectively stained in cryosections incubated with anticD68 antibodies(1:100, Abcam), while the M2 a and M2 c macrophage populations were selectively stained with anti-cD206 antibodies. Expression of interleukin and growth factor genes was evaluated with *** Intrasplenic allogeneic transplantation of the umbilical cord-derived multipotent stromal cells stimulates reparative processes within the residual liver tissue after subtotal resection(removal of 80% of the organ mass), as indicated by increased rates of hepatocyte proliferation and accelerated organ mass recovery. These effects may result from paracrine influence of the transplanted cells on the resident macrophage population of the liver. The transplantation favors polarization of macrophages to M2 phenotype(the M2-polarized macrophages specifically express cD206; they are known to suppress inflammation and support tissue repair). No differentiation of the transplanted cells into a

关键词： Liver Regeneration Multipotent stromal cells Macrophages

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Multifaceted signaling regulators of chondrogenesis:Implications in cartilage regeneration and tissue engineering

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Genes & Diseases 2015年第4期2卷 307-327页

作者： Jordan D.Green viktor Tollemar Mark Dougherty Zhengjian Yan Liangjun Yin Jixing Ye Zachary collier Maryam K.Mohammed Rex c.Haydon Hue H.Luu Richard Kang Michael J.Lee Sherwin H.Ho Tong-chuan He Lewis L.Shi Aravind Athiviraham The University of chicago Pritzker School of Medicine ChicagoIL 60637USA Department of Orthopaedic Surgery and Rehabilitation Medicine The University of Chicago Medical CenterChicagoIL 60637USA Department of Orthopaedic Surgery The Second Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China School of Bioengineering Chongqing UniversityChongqingChina

Defects of articular cartilage present a unique clinical challenge due to its poor self-healing capacity and avascular *** surgical treatment options do not ensure consistent regeneration of hyaline cartilage in favor of fibrous ***,we review the current understanding of the most important biological regulators of chondrogenesis and their interactions,to provide insight into potential applications for cartilage tissue *** include various signaling pathways,including fibroblast growth factors(FGFs),transforming growth factor b(TGF-b)/bone morphogenic proteins(BMPs),Wnt/b-catenin,Hedgehog,Notch,hypoxia,and angiogenic signaling *** and epigenetic regulation of chondrogenesis will also be *** in our understanding of these signaling pathways have led to promising advances in cartilage regeneration and tissue engineering.

关键词： BMPs cartilage cell signaling chondrogenesis FGF Regenerative medicine

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Design and preliminary test results of Daya Bay RPc modules

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chinese Physics c 2011年第9期35卷 844-850页

作者：徐吉磊关梦云杨长根王贻芳张家文 Kirk McDonald Robert Hackenburg Kwong Lau Logan Lebanowski cullen Newsom Lin Shih-Kai Jonathan Link 马烈华 viktor Pě Vit Vorobel 陈进刘金昌周永钊梁昊 Institute of High Energy Physics CAS Graduate University of chinese Academy of Sciences Joseph Henry Laboratories Princeton University Brookhaven National Laboratory Upton Department of Physics University of Houston Virginia Polytechnic Institute and State University charles University Faculty of Mathematics and PhysicsPragueCzech Republic University of Science and Technology of china

Resistive Plate chamber （RPc） modules will be used as one part of the cosmic muon veto system in the Daya Bay reactor neutrino experiment. A total of 189 RPc modules will cover the three water pools in the experiment. To achieve track reconstruction and high efficiency, each module consists of 4 layers, each of which contains two sizes of bare chambers. The placement of bare chambers is reversed in different layers to reduce the overlapping dead areas. The module efficiency and patch emciency were studied both in simulation and test of the data analysis. 143 modules have been constructed and tested. The preliminary study shows that the module and patch 3 out of 4 layers efficiency reaches about 98%.

关键词： RPc RPc modules module efficiency dead area Daya Bay neutrino experiment

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Two novel mutations in theGAN gene causing giant axonal neuropathy

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World Journal of Pediatrics 2018年第3期14卷 298-304页

作者： Monica Irad Normendez-Martínez Lucero Monterde-cruz Roberto Martínez Magdalena Marquez-Harper Nayelli Esquitin-Garduno Margarita Valdes-Flores Leonora casas-Avila Valeria Ponce de Leon-Suarez viktor Javier Romero-Díaz Alberto Hidalgo-Bravo Medical Specialties Hospital Boulevard Milenio 130San Carlos la Roncha37660 LeonGuanajuatoMexico Department of Gene tics National Institute of R ehabilitationAvenue Mexico-Xochimilco 28914389 Me xico CityMexico Department ofHis tology School ofMedicineAutonomous University oft heS tate ofN uevo LeonMonterreyMexico

Background Giant axonal neuropathy (GAN) is a rare neurodegenerative disease transmitted in an autosomal recessive mode. This disorder presents motor and sensitive symptoms with an onset in early childhood. Progressive neurodegeneration makes the patients wheelchair dependent by the end of the second decade of life. Affected individuals do not survive beyond the third decade of life. Molecular analysis has identified mutations in the gene GAN in patients with this disorder. This gene produces a protein called gigaxonin which is presumably involved in protein degradation via the ubiquitin-proteasome system. However, the underlying molecular mechanism is not clearly understood yet. Methods Here we present the fi rst patient from Mexico with clinical data suggesting GAN. Sequencing of the GAN gene was carried out. changes in the nucleotide sequence were investigated for their possible impact on protein function and structure using the publicly available prediction tools PolyPhen-2 and PANTHER. Results The patient is a compound heterozygous carrying two novel mutations in the GAN gene. The sequence analy-sis revealed two missense mutations in the Kelch repeats domain. In one allele, a c>T transition was found in exon 9 at the nucleotide position 55393 (g.55393c>T). In the other allele, a transversion G>T in exon 11 at the nucleotide position 67471 (g.67471G>T) was observed. Both of the bioinformatic tools predicted that these amino acid substitutions would have a negative impact on gigaxonin's function. conclusion This work provides useful information for health professionals and expands the spectrum of disease-causing mutations in the GAN gene and it is the first documented case in Mexican population.

关键词： GAN Genetics Giant axonal neuropathy Incapacity Neurodegenerative

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Electromagnetic-Acoustic Transducers for In-Service Manual Testing of Heated Objects

Electromagnetic-Acoustic Transducers for In-Service Manual T...

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17th World conference on Non-Destructive Testing

作者： Vladimir T.BOBROV Andrey A.SAMOKRUTOV viktor G.SHEVALDYKIN JSc"Spectrum-RII" MoscowRussia

＜正＞The problems of Ultrasonic Testing（UT）of metal products and constructions with the surface being heated up to 300-800c are *** is noted that the process of UT of objects at chemical plants of heat-power, metallurgy industry etc complicates the need to protect Ultrasonic transducers from heated surfaces,hot air and heat radiation from objects,with the operational conditions becoming dangerous. We offer to use electromagnetic-acoustic（EMA）excitation and signal reception technique that does not require direct mechanical contact of the transducer with a heated surface of the object under *** EMA transducers （EMAT）are protected from thermal influence by a thin shield made of heat- resisting material with low thermal conductivity;they do not require the use of couplants and are intended to be used as a part of a serial EMA gauge A1270 for testing of products heated up to 300℃with no additional *** designed time mode follows the *** enables the transducer to work reliably for 8 *** a successful design of the EMAT and the use of a composite protector made of alumina ceramics provide reliable test parameters. The same EMAT can be used to test objects heated up to 700℃.There is a developed carrying-in and -out system for the *** system is provided with a heat-resisting shield that protects the EMAT from thermal influence of the object under test and significantly reduces the influence of it onto an operator. The designed time modes for testing of objects at different temperatures prevents the operating part of the EMAT from overheating and,at the same time provides multiple measurement of heated object *** there is compensation of the thermal influence from an object onto the US wave velocity.

关键词： EMAT Heated products Heat-resistant material US velocity

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