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Molecular rotor based on an oxidized resorcinarene

Organic Chemistry Frontiers 2022年第1期9卷 39-50页

作者： Daniel T.Payne Jan Labuta Zdeněk Futera Václav b.ezina Lenka Hanyková Mandeep K.Chahal Jonathan P.Hill International Center for Materials Nanoarchitectonics National Institute for Materials ScienceNamiki 1-1TsukubaIbaraki 305-0044Japan bInternational Center for Young Scientists National Institute for Materials ScienceNamiki 1-1TsukubaIbaraki 305-0044Japan Institute of Physics Faculty of ScienceUniversity of South BohemiaBranišovská1760ČeskéBudějovice 37005Czech Republic Faculty of Mathematics and Physics Charles UniversityV Holešovičkách 218000 Prague 8Czech Republic

Molecular rotors are an important class of dynamic molecules which have been studied not only for their possible uses as components of molecular machines but also because of potential applications as probes of local viscosity in biological media,especially self-assembled *** the former,factors affecting rotational motility are critical while for the latter the rotor activity must be complexed with an output signal(often fluorescence)for reporting of local *** single stator-double rotor activity of an oxidized resorcinarene(fuchsonarene)macrocycle containing unsaturated hemiquinonoid groups at its meso positions was *** contain two hemiquinonoid substituents at diagonally-opposed meso-positions with two electron rich phenol groups at the remaining meso-positions between the hemiquinonoid *** meso-substituents are in proximity at one side of the resorcinarene macrocycle(so-called rccc-type isomer)with rotational activity of the phenol *** rates of the phenol moieties can be controlled by varying temperature,solvent polarity and acidity of the medium of study with rotation being thermally activated in neutral and acidic media and tunable in the range from 2 s^(−1) to 20000 s^(−1).Experimental and computational data indicate that rotation of the mobile phenol meso-substituents is remotely affected by interactions with acidic solvents at the carbonyl CvO groups of macrocyclic acetyloxy groups,which occurs with the emergence of a lower energy electronic absorption band whose intensity is correlated with both the acidity of the medium and the rotation rate of the phenol ***-dependent DFT calculations suggest that the low energy band is due to a molecular conformational adjustment affecting electronic conjugation caused by strong interaction of macrocyclic acetyloxy carbonyl groups with the acid *** work presents a molecular mechanical model for estimating solution acidity a

关键词： substituent rotation oxidized

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Diporphyrin tweezer for multichannel spectroscopic analysis of enantiomeric excess

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Frontiers of Chemical Science and Engineering 2020年第1期14卷 28-40页

作者： Daniel T.Payne Mandeep KChahal vaclav b.ezina Whitney A.Webre Katsuhiko Ariga Francis D’Souza Jan Labuta Jonathan P.Hill WPI Center for Materials Nanoarchitectonics National Institute for Materials ScienceIbaraki 305-0044Japan Department of Macromolecular Physics Faculty of Mathematics and PhysicsCharles University18000 PragueCzech Republic Department of Chemistry University of North TexasDentonTX 76203USA Department of Advanced Materials Science Graduate School of Frontier SciencesThe University of TokyoChiba 277-8561Japan

Chiral 1,1’-binaphthyl-linked diporphyrin‘tweezers’(R)-1/(S)-1 and the corresponding zinc(II)complexes(R)-2/(S)-2 were prepared as chiral host molecules,and their utility for chiral analyses(especially enantiomeric excess(ee)determinations)were ***(1-n-dodecyl)porphyrins were used for the first time as the interacting *** capabilities of the diporphyrin tweezers were investigated by titrations with(R,R)-and(S,S)-cyclohexane-1,2-diamine(CHDA).The host molecules could be used as multichannel probes of ee by using UVvis,circular dichroism(CD),fluorescence emission and 1H nuclear magnetic resonance(1 H-NMR)*** configurations could also be differentiated using CD or 1HNMR *** three optical techniques give good resolution of ee with reasonable sensitivity considering the low concentrations used(ca.10^-6 mol·L^-1).The ee determination of CHDA enantiomers using NMR spectroscopy is also possible because of the reasonably well separated resonances in the case of(R,R)-and(S,S)-***-metallated(R)-1/(S)-1 hosts could not be used to detect chiral information in a strongly acidic chiral *** work demonstrates the utility of 1,1’-binapthyllinked chiral hosts for chiral analysis of ditopically interacting enantiomers.

关键词： porphyrin dimer chirality enantiomeric excess CD fluorescence

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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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RESULTS FROM IRRADIATION EMbRITTLEMENT MONITORING PROGRAMMES OF RPV’S OPERATED IN THE SLOVAK REPUbLIC NPP’S

RESULTS FROM IRRADIATION EMBRITTLEMENT MONITORING PROGRAMMES...

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第十八届国际反应堆结构力学大会

作者： Peter be■o L’udovít Kupa Martin b.ezina VUJE Inc TrnavaSlovak Republic VUJE Inc TrnavaSlovak Republic VUJE Inc TrnavaSlovak Republic

＜正＞ 1 INTRODUCTION The actual status and main results from the irradiation embrittlement monitoring programmes application on the RPV’s WWER-440 in the Slovak Republic are presented in the paper. 2 SURVEILLANCE PROGRAMMES IN THE SLOVAK NPP’S Five types of surveillance programmes were （are） realized in Slovak NPP’s: in Jaslovske bohunice V-2 NPP （units 3 and 4）, was finished the original "Standard Surveillance Specimen Program" （SSSP）,

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WEIGHTED PSEUDO ALMOST-PERIODIC SOLUTIONS OF SHUNTING INHIbITORY CELLULAR NEURAL NETWORKS WITH MIXED DELAYS

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Acta Mathematica Scientia 2016年第6期36卷 1662-1682页

作者： Mohammed Salah M'HAMDI Chaouki AOUITI Abderrahmane TOUATI Adel M. ALIMI vaclav SNASEL Department of Mathematics University of Carthage Faculty of Sciences of Bizerta BP W 7021 Zarzouna Bizerta Tunisia REGIM-lab: Research Groups on Intelligent Machines University of Sfax National Engineering School of Sfax (ENIS) BP 1173 Sfax 3038 Tunisia VSb Technical University of Ostrava Czech Republic

In this paper, we prove the existence and the global exponential stability of the unique weighted pseudo almost-periodic solution of shunting inhibitory cellular neural networks with mixed time-varying delays comprising different discrete and distributed time delays. Some sufficient conditions are given for the existence and the global exponential stability of the weighted pseudo almost-periodic solution by employing fixed point theorem and differential inequality techniques. The results of this paper complement the previously known ones. Finally, an illustrative example is given to demonstrate the effectiveness of our results.

关键词： weighted pseudo almost-periodic solution shunting inhibitory cellular neuralnetworks mixed delays global exponential stability

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Direct comparison of immunological effects of various nutritional supplements

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临床与病理杂志 2021年第12期41卷 2747-2755页

作者： vaclav Vetvicka Department of Pathology University of LouisvilleLouisvilleKYUSA

Objective:Immunonutrition represents a diet based on the knowledge of basic principles of the immune system and its *** numerous claims,the direct comparison of the immunostimulating effects of natural modulators is limited,making any conclusions *** study focused on most common vitamins and immunonutrients and directly compared their effects on various branches of the immune ***:In this study we used a mouse model to evaluate various aspects of immune reactions,namely phagocytic activity,IL-2 secretion,NK cell activity,antibody formation and growth of breast cancer in order to find out the possible effects of six different immunonutrients and their ***:We found that glucan was in all tests the most active *** effects were observed only in glucan-selenium and glucan-vitamin C *** rest of immunonutrients had only small activity or no activity at ***:based on our results,we concluded that most of vitamins and minerals have only limited,if any,effects on immune activities including *** current study managed to confirm synergistic effects of the beta glucan-vitamin C and beta-glucan-selenium *** studies on possible positive or negative effects of such combination and on mechanisms of action are important.

关键词： vitamin C vitamin D vitamin b6 glucan selenium zinc

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氧气转炉出钢温度的最佳化

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武钢技术 1991年第6期29卷 25-28,33页

作者： J.b.ezina 刘树振

一、前言氧气转炉出钢温度是一个重要的综合性指标,它显著影响炼钢生产的能源消耗。影响出钢温度的因素有:①未脱氧的钢液;②钢包的温度;③出钢的方式和时间以及脱氧和合金化的物理化学参数。出钢时钢包内钢液的热容量、炉外精炼和浇铸... 详细信息

一、前言氧气转炉出钢温度是一个重要的综合性指标,它显著影响炼钢生产的能源消耗。影响出钢温度的因素有:①未脱氧的钢液;②钢包的温度;③出钢的方式和时间以及脱氧和合金化的物理化学参数。出钢时钢包内钢液的热容量、炉外精炼和浇铸过程都对钢液温度有影响。

关键词：氧气转炉出钢温度最佳化

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Relevance of low viral load in haemodialysed patients with chronic hepatitis C virus infection

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World Journal of Gastroenterology 2015年第18期21卷 5496-5504页

作者： Jan Sperl Sona Frankova Renata Senkerikova Magdalena Neroldova vaclav Hejda Miroslava Volfova Dusan Merta Ondrej Viklicky Julius Spicak Milan Jirsa Department of Hepatogastroenterology Institute for Clinical and Experimental Medicine Laboratory of Experimental Hepatology Institute for Clinical and Experimental Medicine Department of Internal Medicine Division of Gastroenterology and Hepatology Charles University Medical School and Teaching Hospital Hepato-gastroenterology 50012 Hradec Kralove Czech Republic Department of Anesthesiology Resuscitation and Intensive Care Institute for Clinical and Experimental Medicine Department of Nephrology Institute for Clinical and Experimental Medicine

AIM: To identify predictors of sustained virological response in hemodialysed patients treated by PEGinterferon α for chronic hepatitis C, genotype ***: The sustained virological response(SVR) rate, IL28 b genotype, IFNL4 genotype, initial viral load(IVL) and other pretreatment variables in 39 endstage renal disease patients(ESRD) on maintenance haemodialysis(HD) infected with hepatitis C virus(HCV), genotype 1b, were compared with a control group of 109 patients with normal kidney function treated within the same period. All the patients were treatment nave and had well compensated liver disease. The ESRD patients received 135 μg of PEGylated interferon α-2a(Peg IFN-α) weekly and a reduced dose of ribavirin(RbV) was administered to 23/39 patients with an initial haemoglobin level > 10 g/d L. Control group patients were given standard doses of Peg IFN-α and RbV. SVR was assessed as HCV RNA negativity 24 wk post-treatment. A t-test or ANOVA were used for comparisons of the means and a χ2 testcompared the *** regression was used to determine significant predictors of *** values for continuous variables were obtained from Receiver Operating Characteristic ***:The distribution of IL28b rs12979860 CC,CT and TT genotypes in the ESRD group was 28.2%,64.1%and 7.7%,respectively,and 19.3%,62.4%and18.3%in the *** IFNL4 genotype was in almost absolute linkage disequlibrium with *** proportion of patients with a low IVL(b CC carriers compared with non-CC carriers in the ESRD group(10/11,90.9%vs 18/28,64.3%,P=0.0035).This difference was not found in the controls(7/22,31.8%vs 44/87,50.6%,P=0.9).The overall SVR rate was 64.1%(25/39)in the ESRD group and 50.5%(55/109)in the control group(P=0.19).11/11(100%)and 19/22(86.4%)IL28b CC patients achieved SVR in the

关键词： End-stage renal disease Hepatitis C virus genotype 1 Interferon alpha IFNL4 Ribavirin

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Analysis of Sheep Lymphocyte Chromosomal Aberrations after Exposition to Chlortetracycline

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Journal of Environmental Protection 2013年第6期4卷 38-42页

作者： Irena Sutiakova vaclav Sutiak Maria Tulenkova Department of biology Faculty of Humanities and Natural SciencesUniversity of PresovPresovSlovak Republic St.Elizabeth University College of Health and Social Work BratislavaSlovak Republic

Tetracyclines are broad spectrum antibiotics and one type of various their compounds—chlortetracycline has been successfully used for our cytogenetic studies. We have selected for these studies the chromosomal assay because it is wellknown cytogenetic biomarker, which has been used to assess DNA damage at the chromosomal level. We analyzed the chromosomal aberrations and mitotic index in peripheral lymphocytes of sheep exposed by chlortetracycline chloride in pure tap water. To the food of the experimental group of animals (à n = 6) were added also 0.35 gof preparation Aureovit12 C80 plv. a. u. v. per kg b. w. and day (i.e. 168 mg of chlortetracycline hydrochloride/kg b. w.) daily in food. The frequencies of aberrant cells (AbC) in the experimental and control groups of sheep were stated to differ significantly (P = 0.001). In experimental group, chromatid breaks were the dominant type of chromosomal aberrations. No statistical differences in mitotic index values were found in the both groups (P > 0.05). Increased frequencies of chromosome aberrations in peripheral lymphocytes of sheep exposed by chlortetracycline in food, suggested a potential hazard which needs the attention from the viewpoint of human and animal health. This knowledge is useful for all, for the human and veterinary medicine, as well as for the aquaculture. Many of these chlortetracycline substances for their environmental persistence and chemical unstability are present in the environment for various periods, and as a result, they are responsible for several effects on human and animal health through food chain.

关键词： Antibiotics Ovine Lymphocytes Chromosomal Assay Genotoxicity Cytotoxicity Health Environment

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biology Inspired Image Segmentation using Methods of Artificial Intelligence

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Journal of Software Engineering and Applications 2012年第12期5卷 172-174页

作者： Radim burget vaclav Uher Jan Masek Departmentof Telecommunication Brno University of TechnologyBrno Czech Republic

In recent years,many efforts have been devoted to image segmentation. Although for a man general image segmentation is considered an easy task, for computers it is still considered to be difficult, computationally intensive and still unresolved task. This work presents an innovative algorithm combining theory of artificial intelligence and knowledge of human eye anatomy. The resulting algorithm has not ambitions to be universal like human brain but can be trained and perform on selected domain. The effectiveness of the algorithm is demonstrated on the selected examples.

关键词： Image processing Image mining Feature extraction Data mining

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