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Soft 2013年第4期2卷 19-26页

作者： Victoria Konovalova yuri Samchenko Ganna Pobigai Anatoly Burban Zoya Ulberg Department of Chemistry National University of Kiev-Mohyla Academy Kiev Ukraine Institute of Biocolloidal Chemistry National Academy of Sciences of Ukraine Kiev Ukraine

The thermo- and pH-responsive hydrogels were synthesized via copolymerization of n-isopropylacrylamide and al-lylamine hydrochloride monomers. The equilibrium swelling of the hydrogels was studied as a function of temperature and pH in aqueous solutions. It was shown that controlled alteration of the hydrogel phase transition temperature can be achieved by changing their composition and pH of the environment. Increase in content of hydrophilic allylamine from 10 to 60 wt% in monomer mixture causes a shift of the phase transition temperature from 35oC to 47oC. Hydrogels with n-isopropylacrylamide/allylamine hydrochloride mass ratio of 3:2 show the highest pH-response. Values of average molecular weight between polymer cross-links, , and Flory parameter, χ, were calculated using temperature dependences of the equilibrium swelling of the synthesized hydrogel.

关键词： Thermo-Responsive Hydrogels Copolymer Hydrogels Allylamine Hydrochloride n-Isopropyl-Acrylamide The Parameter of Flory

Impact of severe plastic deformation on kinetics and thermodynamics of hydrogen storage in magnesium and its alloys

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Journal of Materials Science & Technology 2023年第15期146卷 221-239页

作者： Kaveh Edalati Etsuo Akiba Walter J.Botta yuri Estrin Ricardo Floriano Daniel Fruchart Thierry Grosdidier Zenji Horita Jacques Huot Hai-Wen Li Huai-Jun Lin Ádám Révész Michael J.Zehetbauer WPI International Institute for Carbon-Neutral Energy Research(WPI-I2CNER)Kyushu UniversityFukuokaJapan International Research Center for Hydrogen Energy Kyushu UniversityFukuokaJapan Departamento de Engenharia de Materiais Universidade Federal de São CarlosSao Carlos-SPBrazil Department of Materials Science and Engineering Monash UniversityClaytonVIC 3800Australia Department of Mechanical Engineering the University of Western AustraliaCrawleyWA 6009Australia School of Applied Sciences University of Campinas(UNICAMP)LimeiraSão PauloBrazil Institut néel CNRS&UGA38042 GrenobleFrance JOMI-LEMAn SA 74890 FessyFrance Universitéde Lorraine Laboratory of Excellence on Design of Alloy Metals for low-mass Structures(DAMAS)MetzF-57070France Universitéde Lorraine Laboratoire d’Etude des Microstructures et de Mécanique des Matériaux(LEM3 UMR 7239)MetzF-57070France Graduate School of Engineering Kyushu Institute of TechnologyKitakyushuJapan Magnesium Research Center Kumamoto UniversityKumamotoJapan Synchrotron Light Application Center Saga UniversitySagaJapan Hydrogen Research Institute Universitédu QuébecàTrois-Rivières3351 des ForgesTrois-RivièresQC G9A 5H7Canada Hefei General Machinery Research Institute Hefei 230031China Institute of Advanced Wear&Corrosion Resistance and Functional Materials Jinan UniversityGuangzhou 510632China Department of Materials Physics Eötvös UniversityBudapestH-1518P.O.B.32BudapestHungary Faculty of Physics University of ViennaBoltzmanngasse 5A-1090 WienAustria

Magnesium and its alloys are the most investigated materials for solid-state hydrogen storage in the form of metal hydrides,but there are still unresolved problems with the kinetics and thermodynamics of hydrogenation and dehydrogenation of this group of *** plastic deformation(SPD)methods,such as equal-channel angular pressing(ECAP),high-pressure torsion(HPT),intensive rolling,and fast forging,have been widely used to enhance the activation,air resistance,and hydrogenation/dehydrogenation kinetics of Mg-based hydrogen storage materials by introducing ultrafine/nanoscale grains and crystal lattice *** severely deformed materials,particularly in the presence of alloying additives or second-phase nanoparticles,can show not only fast hydrogen absorption/desorption kinetics but also good cycling *** was shown that some materials that are apparently inert to hydrogen can absorb hydrogen after SPD ***,the SPD methods were effectively used for hydrogen binding-energy engineering and synthesizing new magnesium alloys with low thermodynamic stability for reversible low/room-temperature hydrogen storage,such as nanoglasses,high-entropy alloys,and metastable phases including the high-pressureγ-MgH2 *** work reviews recent advances in the development of Mg-based hydrogen storage materials by SPD processing and discusses their potential in future applications.

关键词： Severe plastic deformation(SPD) nanostructured materials Ultrafine-grained(UFG)materials Magnesium hydride(MgH_(2)) Magnesium-based alloys Hydrogen absorption Hydrogenation kinetics Hydrogen storage thermodynamics

Role of sex hormones in gastrointestinal motility in pregnant and non-pregnant rats

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World Journal of Gastroenterology 2016年第25期22卷 5761-5768页

作者： Juliana Fernandes Matos Madileine Francely Americo yuri Karen Sinzato Gustavo Tadeu Volpato Luciana Aparecida Corá Marcos Felipe Freitas Calabresi Ricardo Brandt Oliveira Debora Cristina Damasceno Jose Ricardo Arruda Miranda Sao Paulo State University BotucatuSP 18618-970Brazil Instituto de Ciencias Biologicas e da Saude Federal University of Mato GrossoBarra do GarcasMT 78600-000Brazil Universidade Estadual de Ciencias da Saude de Alagoas MaceioAL 57010-300Brazil Sao Paulo University Ribeirao PretoSP 14049-900Brazil

AIM: To correlate gastric contractility, gastrointestinal transit, and hormone levels in non-pregnant(estrous cycle) and pregnant rats using noninvasive techniques. METHODS: Female rats(n = 23) were randomly divided into(1) non-pregnant,(contractility, n =6; transit, n = 6); and(2) pregnant(contractility, n = 5; transit, n = 6). In each estrous cycle phase or at 0, 7, 14, and 20 d after the confirmation of pregnancy, gastrointestinal transit was recorded by AC biosusceptometry(ACB), and gastric contractility was recorded by ACB and electromyography. After each recording, blood samples were obtained for progesterone and estradiol determination. RESULTS: In the estrous cycle, despite fluctuations of sex hormone levels, no significant changes in gastrointestinal motility were observed. Days 7 and 14 of pregnancy were characterized by significant changes in the frequency of contractions(3.90 ± 0.42 cpm and 3.60 ± 0.36 cpm vs 4.33 ± 0.25 cpm) and gastric emptying(168 ± 17 min and 165 ± 15 min vs 113 ± 15 min) compared with day 0. On these same days, progesterone levels significantly increased compared with control(54.23 ± 15.14 ng/m L and 129.96 ± 30.52 ng/mL vs 13.25 ± 6.31 ng/mL). On day 14, we observed the highest level of progesterone and the lowest level of estradiol compared with day 0(44.3 ± 15.18 pg/mL vs 24.96 ± 5.96 pg/mL). COnCLUSIOn: Gastrointestinal motility was unaffected by the estrous cycle. In our data, high progesterone and low estradiol levels can be associated with decreased contraction frequency and slow gastric emptying.

关键词： Reproductive physiological process Sex hormones Gastrointestinal motility Magnetic fields Gastric emptying

Supervised vs home-based exercise program in kidney transplant recipients: A pilot pragmatic non-randomized study

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World Journal of Transplantation 2024年第4期14卷 123-132页

作者： Anna Crepaldi Giovanni Piva nicola Lamberti Michele Felisatti Luca Pomidori yuri Battaglia Fabio Manfredini Alda Storari Pablo Jesús López-Soto Unit of nephrology University Hospital of FerraraFerrara 44121Emilia-RomagnaItaly Department of nursing Instituto Maimónides de Investigación Biomédica de CórdobaCordoba 14004AndalusiaSpain Department of neuroscience and Rehabilitation University of FerraraFerrara 44121Emilia-RomagnaItaly Esercizio Vita Medical Fitness Ferrara 44124Emilia-RomagnaItaly Department of Medicine University of VeronaVerona 37100VenetoItaly Department of nursing Maimonides Biomedical Research Institute of CordobaUniversity of CordobaReina Sofía University HospitalCordoba 14004AndalusiaSpain

BACKGROUnD Although the benefits of exercise for kidney transplant recipients(KTRs)have been widely demonstrated,these patients experience several barriers in undertaking a structured exercise program in hospital and non-hospital *** To compare the effects of a supervised moderate-intensity gym-based intervention with a home-based low-intensity walking program on exercise capacity in *** KTRs were asked to choose between two six-month *** first group performed a low-intensity interval walking intervention at home-based exercise intervention (HBex). The second group performed a supervised training program at an adapted physical activitygym (Sgym), including aerobic and resistance training. The outcomes, collected at baseline and at the end of theprograms, included the 6-minute walking test, the peak oxygen consumption (VO_(2)peak) during a treadmill test,the 5-time sit-to-stand test, and blood *** patients agreed to participate and self-selected into the HBex (n = 9) and Sgym (n = 8) groups. Twopatients in the Sgym group dropped out because of familial problems. At baseline, patients in the HBex group weresignificantly older and had lower walking distance, VO_(2)peak, and lower limb strength. Primary outcome changeswere significantly greater in the HBex group than in the Sgym group (52 ± 23 m vs 8 ± 34;P = 0.005). no othersignificant differences between groups were observed. Both groups improved most of the outcomes in the withingroupcomparisons, with significant variations in VO_(2) ***-month moderate-intensity supervised or low-intensity home-based training programs effectively improvedexercise capacity in KTRs. Gym-based programs combine aerobic and resistance training;however, in-homewalking may be proposed for frail KTRs.

关键词： Exercise Transplantation Walking Training nephrology Kidney disease

Preparation of Fluoroalkyl End-Capped Oligomer/Cyclodextrin Polymer Composites: Development of Fluorinated Composite Material Having a Higher Adsorption Ability toward Organic Molecules

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Journal of Encapsulation and Adsorption Sciences 2018年第2期8卷 117-138页

作者： Jun-Ichi Suzuki Yutaro Takegahara yuri Oikawa Yuta Aomi Hideo Sawada Department of Frontier Materials Chemistry Graduate School of Science and Technology Hirosaki University Hirosaki Japan Kankyo Kogaku Hirosaki Japan

Fluoroalkyl end-capped vinyltrimethoxysilane oligomer [RF-(CH2CHSi(OMe)3)n-RF;RF = CF(CF3)OCF7, n = 2, 3;RF-(VM)n-RF] was applied to the preparation of fluoroalkyl end-capped vinyltrimethoxysilane oligomer/α-, β-, γ-cyclodextrin polymers (α-, β-, γ-CDPs) composites [RF-(VM-SiO2)n-RF/α-, β-, γ-CDPs] by the sol-gel reaction of the corresponding oligomer in the presence of the α-, β-, γ-CDPs under alkaline conditions. The RF-(VM-SiO2)n-RF/α-, β-, γ-CDPs composites thus obtained were found to give a good dispersibility toward the traditional organic media except for water, and were applied to the surface modification of glass to provide a sueperoleophilic/superhydrophobic characteristic on the modified surface, although the corresponding RF-(VM-SiO2)n-RF nanocomposites can give a usual oleophobic/superhydrophobic property on the surface. These composites powders were also found to be applicable to the packing material for the column chromatography to separate the mixture of oil/water and the water in oil (W/O) emulsions. More interestingly, these composite powders were found to have a higher adsorption ability toward not only low-molecular weight aromatic compounds such as bisphenol A and bisphenol AF but also volatile organic compounds, compared to that of the pristine α-, β-, γ-CDPs.

关键词： Fluorinated Oligomeric Composite Cyclodextrin Polymer Surface Modification Superoleophilic Superhydrophobic Property Separation of Oil and Water Organic Molecule VOC Adsorption Ability

Top Limit Characteristics of new Type Cascade PC on the Basis of Homogeneous Semiconductor

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Journal of Energy and Power Engineering 2013年第10期7卷 1892-1897页

作者： yuri D. Arbuzov Vladimir M. Evdokimov Olga V. Shepovalova The All-Russian Research Institute for Electrification of Agriculture (GnU VIESH) Moscow 109456 Russia

A new type homogeneous planar PC （photoelectric converter） on the basis of multijunction semiconductor n＋-p-p＋-n＋-p-p＋-...-n＋-p-p＋ structure has been investigated. The entire structure is a cascade PC consisting of a number of elements of the structure--single PCs connected in series and illuminated by light that has consistently passed through the previous semiconductor layers. The theory of converter of both monochromatic and solar radiation has been developed and the limiting values of their photoelectric and power characteristics have been determined, including the optimal thickness and number of single PCs layered on a base PC, their spectral sensitivity, current-voltage characteristics and efficiency. The open-circuit voltage grows practically linearly with the number of elements in the cascade. The top efficiency limit for a certain optimal elements number reaches its maximum that exceeds considerably that of the base PC, especially in the range of low collecting coefficient of charge carriers in the base PC.

关键词： Photoelectric converter multijunction monochromatic and solar radiation photoelectric and power characteristics.

Reactivity of n-Methylidenemalonates of 3-Arylaminoindoles and p-Dimethylamino-n-Phenylaniline in the Course of Their Analysis by Electrospray Ionization Mass Spectrometry

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International Journal of Analytical Mass Spectrometry and Chromatography 2017年第1期5卷 1-16页

作者： yuri S. nekrasov nikolai S. Ikonnikov yuri A. Borisov Sergey S. Kiselev Albert G. Kornienko Valeriya S. Velezheva Yury I. Lyakhovetsky A.n. nesmeyanov Institute of Organoelement Compounds The Russian Academy of Sciences Moscow Russia

The behavior of n-methylidenemalonates of 3-arylaminoindoles and p-dimetylamino-n-phenylanyline (M = Ana) was studied during their analysis with ESI mass spectrometer operated in negative (nI) and positive (PI) ion modes. Anions [A] and both [M + H]+ and [M + na]+ were recorded under conditions of the nI-ESI and PI-ESI, respectively. The fragmentation processes of [A] and [M + H]+ were found that probably occurred as “insource collusion induced dissociation”. The main paths for [A] proved to be elimination of CO2 and breakage of the n-methylidenemalonate bond. A route [A]- - CO2 - ROH (R = Me or Et) was less expressed and occurred for the indolyl-containing compounds with the nH bond only. Experiments employing heavy water demonstrated the isotope exchange to occur involving the hydrogen atom of this bond. This and other facts evidenced that the last fragmentation included abstraction of just this atom. Quantum-chemical calculations allowed picking out a structure for the product ion from the possible ones. The calculations also indicated that the protonation of M occurred at the anionic oxygen atom of the malonate moiety. The fragmentation of [M + H]+ ions included elimination of two water molecules that was supported by their MS2 spectra. A common feature of the nI- and PI-ESI mass spectra was the presence of oligomeric ions, up to tetramers and trimers for the nI- and PI-ESI ones, respectively. The oligomers were formed by interaction of the corresponding ions with neutral molecules. When ions contained extra hydrogen atoms, they were introduced by hydrolysis.

关键词： n-Methylidenemalonates of 3-Aminoarylindoles Electrospray Ionization Fragmentation Processes Quantum-Chemical Calculations Ion Structures

nonlinear polaritons in a monolayer semiconductor coupled to optical bound states in the continuum

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Light(Science & Applications) 2020年第1期9卷 1480-1487页

作者： Vasily Kravtsov Ekaterina Khestanova Fedor A.Benimetskiy Tatiana Ivanova Anton K.Samusev Ivan S.Sinev Dmitry Pidgayko Alexey M.Mozharov Ivan S.Mukhin Maksim S.Lozhkin yuri V.Kapitonov Andrey S.Brichkin Vladimir D.Kulakovskii Ivan A.Shelykh Alexander I.Tartakovskii Paul M.Walker Maurice S.Skolnick Dmitry n.Krizhanovskii Ivan V.Iorsh ITMO University Saint Petersburg 197101Russia St.Petersburg Academic University Saint Petersburg 194021Russia Saint Petersburg State University ul.Ulyanovskaya 1Saint Petersburg 198504Russia Institute of Solid State Physics RASChernogolovka 142432Russia Science Institute University of IcelandDunhagi 3IS-107ReykjavikIceland Department of Physics and Astronomy University of SheffieldSheffield S37RHUK

Optical bound states in the continuum(BICs)provide a way to engineer very narrow resonances in photonic *** extended interaction time in these systems is particularly promising for the enhancement of nonlinear optical processes and the development of the next generation of active optical ***,the achievable interaction strength is limited by the purely photonic character of optical ***,we mix the optical BIC in a photonic crystal slab with excitons in the atomically thin semiconductor MoSe_(2) to form nonlinear exciton-polaritons with a Rabi splitting of 27 meV,exhibiting large interaction-induced spectral *** asymptotic BIC-like suppression of polariton radiation into the far field toward the BIC wavevector,in combination with effective reduction of the excitonic disorder through motional narrowing,results in small polariton linewidths below 3 *** with a strongly wavevector-dependent Q-factor,this provides for the enhancement and control of polariton–polariton interactions and the resulting nonlinear optical effects,paving the way toward tuneable BIC-based polaritonic devices for sensing,lasing,and nonlinear optics.

关键词： polar nonlinear continuum

Quantitative tracking of trans-synaptic nose-to-brain transport of nanoparticles and its modulation by odor,aging,and Parkinson’s disease

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nano Research 2023年第5期16卷 7119-7133页

作者： Alexander V.Romashchenko Dmitrii V.Petrovskii Sergey Yu.Trotsky Ksenia n.Morozova nina B.Illarionova Maria V.Zhukova Elena V.Kiseleva Marina B.Sharapova Daniil S.Zuev Konstantin E.Kuper Sergey Yu.Taskaev Anna I.Kasatova Dmitrii A.Kasatov Olga I.Solovieva Ivan A.Razumov Ludmila A.Gerlinskaya Mikhail P.Moshkin yuri M.Moshkin The Federal Research Center Institute of Cytology and Genetics SB RASAcademician Lavrentiev Avenue10Novosibirsk 630090Russia International tomography center Institutskaya st.3ANovosibirsk 630090Russia G.K.Boreskov Institute of Catalysis SB RASAcademician Lavrentiev Avenue5Novosibirsk 630090Russia The Federal Research Center Budker Institute of nuclear Physics SB RASAcademician Lavrentiev Avenue11Novosibirsk 630090Russia Institute of Computational Technologies Academician M.A.Lavrentiev avenue6Novosibirsk 630090Russia Institute of Gene Biology Russian Academy of SciencesMoscow 117334Russia Institute of Molecular and Cellular Biology SB RASAcad.Lavrentiev Ave8/2Novosibirsk 630090Russia Federal Research Centre of Biological Systems and Agrotechnologies RASst.January 929Orenburg 460000Russia

nanoparticles(nPs)can be transported via the nose-to-brain(n_(2)B)***,quantitative data on their spatiotemporal dynamics and regulation of the n_(2)B transport are largely *** surveyed metal oxide/hydroxide nPs as magnetic resonance imaging(MRI)contrasts for quantitative n_(2)B *** containing divalent transition metals were the only ones capable of n_(2)B *** T1-weighted(T1W)MRI,we showed that Mn_(3)O_(4)-nPs were readily engulfed by olfactory receptor neurons(ORns)without disrupting olfactory sensing,we mapped their n_(2)B *** neurons,the Mn_(3)O_(4)-nPs were localized to the cytosol,mitochondria,vesicles,moved at mixed fast and slow axonal transport velocities intraand extra-vesicularly through *** nPs’axonal transport is dependent on neuronal activity and microtubule *** Mn_(3)O_(4)-nPs were trans-synaptically transmitted through at least four synapses across the olfactory ***-synaptic transmission of the nPs was dependent on n-type Ca^(2+)channels and nMDA receptors but blocked by GABAB receptor activation.A five-parameter Weibull signal increase/decrease model fitted to the T1W MRI data allowed for estimating kinetic parameters of Mn_(3)O_(4)-nP accumulation/*** and relative accumulation rates,but not elimination,correlated negatively with the number of synapses from ORns,indicating a coupling of the nPs’n_(2)B transport with spontaneous neuronal ***,olfactory stimuli(2,5-dimethylpyrazine and acetophenone)significantly modulated and rerouted the Mn_(3)O_(4)-nP n_(2)B transport odor ***,the nPs’trans-synaptic transmission was impaired by aging and the onset of Parkinson’s *** data suggest new approaches to diagnostics,functional neuroimaging,controlling n_(2)B drug delivery.

关键词： Mn_(3)O_(4)nanoparticles magnetic resonance imaging(MRI) nose-to-brain transport trans-synaptic transmission olfactory stimulation