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Characterization of cerebral blood flow dynamics with multiscale entropy

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Journal of Innovative Optical Health Sciences 2017年第5期10卷 85-93页

作者： Alexey n.Pavlov Arkady S.Abdurashitov Olga n.Pavlova Maria V.Ulanova Anastasia A.Bodrova natalia A.Shushunova alexander P.Khorovodov Oxana V.Semyachkina-Glushkovskaya Yuri Gagarin State Technical University of Saratov 77 Politechnicheskaya Street Saratov 410054Russia Saratov national Research State University 83 Astrakhanskaya Street Saratov 410012Russia

Based on the laser speckle contrast imaging(LSCI)and the multiscale entropy(MSE),we study in this work the blood flow dynamics at the levels of cerebral veins and the surrounding network of microcerebral *** discuss how the phenylephrine-related acute peripheral bypertension is refected in the cerebral circulation and show that the observed changes are scale dependent,and they are signifcantly more pronounced in microcerebral vessels,while the macrocerebral dynamics does not demonstrate authentic inter-group *** also consider the permeability of blood-brain barrier(BBB)and study its opening caused by sound *** show that alterations associated with the BBB opening can be revealed by the analysis of blood flow at the level of macrocerebral vessels.

关键词： Cerebral blood flow laser speckle contrast imaging arterial pressure complexity

Microstructure and mechanical properties of CoCrFeMnni high entropy alloy with ultrasonic nanocrystal surface modification process

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Journal of Materials Science & Technology 2020年第22期54卷 123-130页

作者： Timothy alexander Listyawan Hyunjong Lee nokeun Park Unhae Lee School of Materials Science and Engineering Yeungnam University280 Daehak-roCyeongsanGyeongsangbuk-do 38541Republic of Korea Advanced Process and Materials R&D Group Korea Institute of Industrial TechnologyIncheon 21999Republic of Korea Institute of Materials Technology Yeungnam University280 Daehak-roGyeongsanGyeongsangbuk-do 38541Republic of Korea POSCO Technical Research Laboratories Gwangyang 57807Republic of Korea

In this study, mechanical properties improvement of equiatomic CoCrFeMnni treated with an ultrasonic nanocrystal surface modification(UnSM) was studied. The applied UnSM treatment with static loads of 10 n, 20 n, and 60 n provided a severe plastic deformation, which produced a gradient structure. The nearsurface area exhibited a high number of dislocation densities and deformation twin interaction, leading to a surface strengthening and hardness improvement of up to 112% than the deformation-free interior region. Increment of dislocation densities and deformation twin formation on the surface also enhanced the yield and ultimate tensile strength of the UnSM-treated specimens. Furthermore, the combination of hard nanocrystallites layer on the surface and ductile coarse grain in the specimen interior as a result of the UnSM treatment successfully maintained the strength–ductility balance of the CoCrFeMnni.

关键词： High-entropy alloy Ultrasonic nanocrystal surface modification Severe plastic deformation Microstructures Mechanical properties

Conventional endoscopic retrograde cholangiopancreaticography vs the Olympus V-scope system

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World Journal of Gastroenterology 2013年第12期19卷 1936-1942页

作者： Martin Raithel Andreas ngel Jürgen Maiss Dane Wildner alexander Fritzkarl Hagel Sandra Braun Hiwot Diebel Eckhart Georg Hahn Department of Medicine 1 GastroenterologyEndoscopy University Erlangen-Nuremberg

AIM: To compare the new Olympus V-scope (VS) to conventional endoscopic retrograde cholangiopancreati-cography (ERCP). METHODS: Forty-nine patients with previous endoscopic papillotomy who were admitted for interventional ERCP for one of several reasons were included in this single-centre, prospective randomized study. Consecutive patients were randomized to either the VS group or to the conventional ERCP group. ERCP-nave patients who had not undergone papillotomy were excluded. The main study parameters were interventional examination time, X-ray time and dose, and premedication dose (all given below as the median, range) and were investigated in addition to each patient's clinical outcome and complications. Subjective scores to assess each procedure were also provided by the physicians and endoscopy assistants who carried out the procedures. A statistical analysis was carried out using the Wilcoxon rank-sum ***: Twenty-five patients with 50 interventions were examined with the VS ERCP technique, and 24 patients with 47 interventions were examined using the conventional ERCP technique. There were no significant differences between the two groups regarding the age, sex, indications, degree of ERCP difficulty, or interventions performed. The main study parameters in the VS group showed a nonsignificant trend towards a shorter interventional examination time (29 min, 5-50 min vs 31 min, 7-90 min, P = 0.28), shorter X-ray time (5.8 min, 0.6-14.1 min vs 6.1 min, 1.6-18.8 min, P = 0.48), and lower X-ray dose (1351 cGy/m2 , 159-5039 cGy/m2 vs 1296 cGy/m2 , 202.2-6421 cGy/m 2 , P = 0.34). A nonsignificant trend towards fewer adverse events occurred in the VS group as compared with the conventional ERCP group (cholangitis: 12% vs 16%, P = 0.12; pain: 4% vs 12.5%, P = 0.33; post-ERCP pancreatitis: 4% vs 12.5%, P = 0.14). In addition, there were no statistically significant differences in assessment by the physicians and endoscopy assistants using subjective questio

关键词： Endoscopic retrograde cholangiopancre-aticography Short guidewire endoscopic retrograde cholangiopancreaticography system X-ray protection V-scope Bile duct stenosis

Enhanced second-harmonic generation from two-dimensional MoSe_(2) on a silicon waveguide

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Light(Science & Applications) 2017年第1期6卷 505-511页

作者： Haitao Chen Vincent Corboliou alexander S Solntsev Duk-Yong Choi Maria A Vincenti Domenico de Ceglia Costantino de Angelis Yuerui Lu Dragomir n neshev nonlinear Physics Centre Research School of Physics and EngineeringAustralian National UniversityCanberraACT 2601Australia Institut d’Optique Graduate School UniversitéParis-SudPalaiseau 91127France Laser Physics Centre Research School of Physics and EngineeringAustralian National UniversityCanberraACT 2601Australia national Research Council Charles M.Bowden LaboratoryRedstone ArsenalValhermoso SpringsAL 35898-5000USA Department of Information Engineering and InO CnR University of BresciaVia Branze 38Brescia 25123Italy Research School of Engineering College of Engineering and Computer ScienceAustralian National UniversityCanberraACT 2601Australia

Two-dimensional transition-metal dichalcogenides(TMDCs)with intrinsically broken crystal inversion symmetry and large secondorder nonlinear responses have shown great promise for future nonlinear light ***,the sub-nanometer monolayer thickness of such materials limits the length of their nonlinear interaction with ***,we experimentally demonstrate the enhancement of the second-harmonic generation from monolayer MoSe_(2) by its integration onto a 220-nm-thick silicon *** on-chip integration allows for a marked increase in the interaction length between the MoSe_(2) and the waveguide mode,further enabling phase matching of the nonlinear *** demonstrated TMDC–silicon photonic hybrid integration opens the door to second-order nonlinear effects within the silicon photonic platform,including efficient frequency conversion,parametric amplification and the generation of entangled photon pairs.

关键词： 2D material MoSe_(2) SHG waveguide

A class of high-mobility layered nanomaterials by design

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Journal of Materials Science & Technology 2023年第33期164卷 179-187页

作者： Dmitry V.Averyanov Ivan S.Sokolov Oleg E.Parfenov alexander n.Taldenkov Oleg A.Kondratev Andrey M.Tokmachev Vyacheslav G.Storchak national Research Center “Kurchatov Institute” Kurchatov Sq.1Moscow 123182Russia

Design of materials with particular functional properties is indispensable albeit very *** and structural analogies can be helpful in this endeavor,especially when a particular combination of properties is sought *** aim is to bundle together 3 characteristics:high carrier mobility,magnetism,and scalability to nanomaterials in the form of a film–such a combination is particularly advantageous for ***,inspired by recent studies of MAl_(2)Si_(2)and related compounds,we develop magnetic EuAl_(2)Ge_(2)and non-magnetic SrAl_(2)Ge_(2)nanomaterials with high carrier *** syntheses employing sacrificial 2D templates result in epitaxial films of MAl_(2)Ge_(2)seamlessly integrated with *** syntheses are followed by a study of the atomic structure,magnetic and electron transport *** particular,the films demonstrate high carrier mobility,exceeding 10,000 cm^(2)V^(-1)s^(-1)in the case of EuAl_(2)Ge_(2),making the materials appealing for *** together,MAl_(2)Ge_(2)and MAl_(2)Si_(2)form a class of high-mobility layered nanomaterials.

关键词： High carrier mobility Magnetism SrAl_(2)Ge_(2) EuAl_(2)Ge_(2) Germanium

Could wastewater analysis be a useful tool for China?——A review

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Journal of Environmental Sciences 2015年第1期27卷 70-79页

作者： Jianfa Gao Jake O'Brien Foon Yin Lai alexander L.n.van nuijs Jun He Jochen F.Mueller Jingsha Xu Phong K.Thai Faculty of Science and Engineering University of Nottingham Ningbo China national Research Centre for Environmental Toxicology The University of Queensland Toxicological Center University of Antwerp

Analysing wastewater samples is an innovative approach that overcomes many limitations of traditional surveys to identify and measure a range of chemicals that were consumed by or exposed to people living in a sewer catchment area. First conceptualised in 2001, much progress has been made to make wastewater analysis（WWA） a reliable and robust tool for measuring chemical consumption and/or exposure. At the moment, the most popular application of WWA, sometimes referred as sewage epidemiology, is to monitor the consumption of illicit drugs in communities around the globe, including China. The approach has been largely adopted by law enforcement agencies as a device to monitor the temporal and geographical patterns of drug consumption. In the future, the methodology can be extended to other chemicals including biomarkers of population health（e.g. environmental or oxidative stress biomarkers, lifestyle indicators or medications that are taken by different demographic groups） and pollutants that people are exposed to（e.g. polycyclic aromatic hydrocarbons,perfluorinated chemicals, and toxic pesticides）. The extension of WWA to a huge range of chemicals may give rise to a field called sewage chemical-information mining（SCIM） with unexplored potentials. China has many densely populated cities with thousands of sewage treatment plants which are favourable for applying WWA/SCIM in order to help relevant authorities gather information about illicit drug consumption and population health status. However, there are some prerequisites and uncertainties of the methodology that should be addressed for SCIM to reach its full potential in China.

关键词： Drug consumption Wastewater analysis Biomarkers Population health

A pilot study of the dynamics of tissue oxygenation in vivo using time-resolved phosphorescence imaging

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Journal of Innovative Optical Health Sciences 2021年第5期4卷 15-24页

作者： natalia Kazachkina Julia Lymar Vladislav Shcheslavskiy alexander Savitsky A.n.Bach Institute of Biochemistry Research Center of Biotechnology of the Russian Academy of Sciences Moscow 119071Russian Federation Institute of Experimental Oncology and Biomedical Technologies Privolzhsky Research Medical University Sq Minin and Pozharsky10/1603005 Nizhny Novgorod Russian Federation Becker and Hickl GmbH nunsdorfer Ring 7-912277 BerlinGermany

Oxygenation of tissues plays an important role in the development and progression of tumor to treatment *** of metalloporphyrines phosphorescence quenching by oxygen is one of the ways to measure dynamics of the oxygen concentration in the tissues by phosphorescence lifetime imaging of meso-tetra(sulfophenyl)tetrabenzoporphyrin Pd(Ⅱ)(TBP)using the time-correlated single photon counting(TCSPC)*** has been shown that phosphorescence lifetime of the sensor in S37 tumor in vivo varied in the range of 130 to 290μs after both topical and intravenous administration of *** indicates that oxygen level in tumors was lower compared to normal tissues where TBP phosphorescence has not been *** lifetimes of TBP increased in the solid tumor and in the muscle after photodynamic therapy of solid tumor that demonstrates oxygen consumption during treatment and possibly stopping the blood flow and hence the oxygen supply to the tissues.

关键词： Phosphorescence oxygen sensor metalloporphyrines TCSPC

Forces and energetics of intermittent swimming

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Acta Mechanica Sinica 2017年第4期33卷 725-732页

作者： Daniel Floryan Tyler Van Buren alexander J.Smits Department of Mechanical and Aerospace Engineering Princeton University Princeton NJ 08544 USA

Experiments are reported on intermittent swimming motions. Water tunnel experiments on a nominally two-dimensional pitching foil show that the mean thrust and power scale linearly with the duty cycle, from a value of 0.2 all the way up to continuous motions, indicating that individual bursts of activity in intermittent motions are independent of each other. This conclusion is corroborated by particle image velocimetry（PIV） flow visualizations, which show that the main vortical structures in the wake do not change with duty cycle. The experimental data also demonstrate that intermittent motions are generally energetically advantageous over continuous motions. When metabolic energy losses are taken into account, this conclusion is maintained for metabolic power fractions less than 1.

关键词： intermittent swimming maintained conclusion cycle thrust favorable producing aquatic circles

High Q-factor controllable phononic modes in hybrid phononic–dielectric structures

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Advanced Photonics 2019年第2期1卷 41-45页

作者： Bo Qiang alexander M.Dubrovkin Harish n.S.Krishnamoorthy Qian Wang Cesare Soci Ying Zhang Jinghua Teng Qi Jie Wang nanyang Technological University Centre for Disruptive Photonic TechnologiesThe Photonic InstituteSchool of Physical and Mathematical SciencesSingapore nanyang Technological University Centre for OptoElectronics and BiophotonicsSchool of Electrical and Electronic EngineeringSingapore Agency for Science Technology and ResearchInstitute of Materials Research and EngineeringSingapore Agency for Science Technology and ResearchInstitute of Manufacturing TechnologySingapore

Phonon polariton resonances in the mid-infrared spectral range demonstrate properties superior to noble metal-based plasmonics,owing to smaller dissipative loss and better field ***,a conventional way to excite the localized phonon resonance involves ion etching,which reduces the attainable quality factors(Q-factors)of the *** show that by introducing a deep subwavelength layer of dielectric gratings on a phononic substrate,localized dipolar resonance and higher order modes with high Q-factors 96 and 195,respectively,can be *** further demonstrate,via experiments and simulations,that the resonant wavelength and field confinement can be controlled by coupling the localized hybrid mode with propagating surface *** also observed for the first time the coupling between a localized dipolar mode and a propagating higher-order surface phonon-polariton *** results will be useful in designing on-chip,low-loss,and highly integrated phononic devices in the infrared spectral domain.

关键词： hybrid resonance high Q-factor phonon resonance mode splitting