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Lanthanide mechanoluminescence

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Journal of Rare Earths 2018年第1期36卷 1-41页

作者： Jean-Claude G.Bünzli ka-Leung Wong Institute of Chemical Sciences and Engineering Swiss Federal Institute of Technology Lausanne (EPFL) CH-1015 Lausanne Switzerland Department of Chemistry Hong Kong Baptist University Kowloon Tong Hong Kong China

Mechanoluminescence （ML） is the emission of light consecutive to a mechanical force or stress imposed to a crystalline material. Many inorganic and organic compounds present this phenomenon that is known for over 400 years. Lanthanide and uranyl salts were among the first substances investigated for this property. Mechanoluminescence, also referred to as triboluminescence, is often considered as being a badly understood phenomenon. In fact it is because of two main reasons. Firstly, a variety of different mechanical stresses, from simple rubbing, to applied pressure, crushing, impact of a weight, ultrasound, laser-generated shock wave, crystallization, dissolution of crystals, or even wind can trigger it. Secondly, ML is very sensitive to the purity and morphology of the sample： in inorganic compounds, generation of traps by doping ＂impurities＂（e.g. lanthanide ions） is responsible for light emission so that the exact composition of the sample has to be known to a very detailed level; for chelates, the crystallization conditions are crucial since they often generate extended networks of weak interactions that are instrumental in triggering ML when they are broken. In fact mechanisms of ML are relatively well known and theories and models often reproduce very well the experiments. Additionally, practical applications are at hand, for example stress, crack, and impact sensors based on SrAI204：Eu11 or Et3NH[Eu（dbm）4] are used to test structures and materials as diverse as road bridges, reinforced concrete elements, pressur- ized containers or airplane wings and to image the propagation of cracks or stress distribution. Military and security applications involve detecting the passage of vehicle or soldiers and producing counter- feiting inks while more joyful applications are luminous balls, wrapping papers and adhesive tapes. Not only bulk materials, but micro- and nanoparticles feature mechanoluminescent properties and single particle manipulation under an AFM allows

关键词： MechanoluminescenceRare earthsStress sensorsPressure sensorsImpact sensors

Leveraging Retinal Fundus Images with Deep Learning for Diabetic Retinopathy Grading and Classification

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Computer Systems Science & Engineering 2023年第8期46卷 1901-1916页

作者： Mohammad Yamin Sarah Basahel Saleh Bajaba mona Abusurrah ELaxmi Lydia Department of Management Information Systems Faculty of Economics and Administration King Abdulaziz UniversityP.O.Box 80201Jeddah21589Saudi Arabia Department of Business Administration King Abdulaziz UniversityP.O.Box 80201Jeddah21589Saudi Arabia Department of Management Information Systems College of Business AdministrationTaibah UniversityAl-MadinahSaudi Arabia Department of Computer Science and Engineering GMR Institute of TechnologyAndhra PradeshRajam 532127India

Recently,there has been a considerable rise in the number of diabetic patients suffering from diabetic retinopathy(DR).DR is one of the most chronic diseases and makes the key cause of vision loss in middle-aged people in the developed *** detection of DR becomes necessary for decreasing the disease severity by making use of retinal fundus *** article introduces a Deep Learning Enabled Large Scale Healthcare Decision Making for Diabetic Retinopathy(DLLSHDM-DR)on Retinal Fundus *** proposed DLLSHDM-DR technique intends to assist physicians with the DR decision-making *** the DLLSHDM-DR technique,image preprocessing is initially performed to improve the quality of the fundus ***,the DLLSHDM-DR applies HybridNet for producing a collection of feature *** retinal image classification,the DLLSHDM-DR technique exploits the Emperor Penguin Optimizer(EPO)with a Deep Recurrent Neural Network(DRNN).The application of the EPO algorithm assists in the optimal adjustment of the hyperparameters related to the DRNN model for DR detection showing the novelty of our *** assuring the improved performance of the DLLSHDMDR model,a wide range of experiments was tested on the EyePACS *** comparison outcomes assured the better performance of the DLLSHDM-DR approach over other DL models.

关键词： Decision making healthcare sector deep learning diabetic retinopathy emperor penguin optimizer

Study of the attenuation relationship for the Wenchuan M_s 8.0 earthquake

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Earthquake Engineering and Engineering Vibration 2015年第1期14卷 1-11页

作者： Sin-Chi Kuok Iok-Tong Ng ka-Veng Yuen Faculty of Science and Technology University of Macao

Prediction of peak ground acceleration is an essential element in engineering seismology and it has received great attention in last few decades. In this paper, a comprehensive database of the strong-motion records of the 2008 great Wenchuan Ms 8.0 earthquake is analyzed to investigate the seismic attenuation relationship and the directivity effects. In contrast to most existing seismic attenuation models, the proposed model considers explicitly the directivity effect which has primary influence on the magnitude of ground motion. Bayesian model updating is used to obtain the model parameters and the associated uncertainty. Comparative study is performed with the well-known Boore-Joyner-Fumal empirical formula. Results show that consideration of the directivity effect is vital in modeling the seismic attenuation relationship.

关键词： Bayesian inference Boore-Joyner-Fumal attenuation relationship directivity peak ground acceleration seismic attenuation model

Dimethylether production on zeolite catalysts activated by Cl^-,F^- and / or ultrasonication

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燃料化学学报 2016年第4期44卷 428-436页

作者： Sameh M.K.Aboul-Fotouh Noha A.K.Aboul-Gheit mona A.Naghmash Chemistry Department Faculty of Education Ain Shams University Roxy Cairo 11757 Egypt Faculty of Science Chemistry Department Northern Border University Arar 91431 Kingdom of Saudi Arabia Egyptian Petroleum Research Institute Cairo 11787 Egypt

The chlorinated and fluorinated zeolite catalysts were prepared by the impregnation of zeolites( H-ZSM-5,H-MOR or H-Y) using two halogen precursors( ammonium chloride and ammonium fluoride) in this study. The influence of ultrasonic irradiation was evaluated for optimizing both halogen precursors for production of dimethylether( DME) via methanol dehydration in a fixed bed reactor. The catalysts were characterized by SEM,XRD,BET and NH3-TPD. The reaction conditions were temperatures from 100 to 300 ℃ and a WHSV = 15. 9 h-1. All halogenated catalysts showhigher catalytic activities at all reaction temperatures studied. However, the halogenated zeolite catalysts prepared under ultrasonic irradiation showhigher performance for DME formation. The chlorinated zeolite catalysts show higher activity and selectivity for DME production than the respective fluorinated versions.

关键词： ultrasonication DME zeolite Cl^- F^-

Calcitonin and vitamin D3 have high therapeutic potential for improving diabetic mandibular growth

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International Journal of Oral Science 2016年第1期8卷 39-44页

作者： mona A Abbassy Ippei Watari Ahmed S Bakry Takashi Ono Ali H Hassan Orthodontic Department Faculty of DentistryKing Abdulaziz UniversityJeddahSaudi Arabia Department of Orofacial Development and Function Division of Oral Health SciencesGraduate SchoolTokyo Medical and Dental UniversityTokyoJapan Alexandria University AlexandriaEgypt Conservative Dentistry Department Faculty of DentistryKing Abdulaziz UniversityJeddahSaudi Arabia Cariology and Operative Dentistry Department Graduate School of Medical and Dental SciencesTokyo Medical&Dental UniversityTokyoJapan Conservative Dentistry Department Faculty of DentistryAlexandria UniversityAlexandriaEgypt

The goal of this study was to assess the effect of the intermittent combination of an antiresorptive agent （calcitonin） and an anabolic agent （vitamin D3） on treating the detrimental effects of Type 1 diabetes mellitus （DM） on mandibular bone formation and growth. Forty 3-week-old male Wistar rats were divided into four groups： the control group （normal rats）, the control C＋D group （normal rats injected with calcitonin and vitamin D3）, the diabetic C＋D group （diabetic rats injected with calcitonin and vitamin D3） and the diabetic group （uncontrolled diabetic rats）. An experimental DM condition was induced in the male Wistar rats in the diabetic and diabetic C＋ D groups using a single dose of 60 ***-1 body weight of streptozotocin. Calcitonin and vitamin D3 were simultaneously injected in the rats of the control C＋D and diabetic C＋D groups. All rats were killed after 4 weeks, and the right mandibles were evaluated by micro-computed tomography and histomorphometric analysis. Diabetic rats showed a significant deterioration in bone quality and bone formation （diabetic group）. By contrast, with the injection of calcitonin and vitamin D3, both bone parameters and bone formation significantly improved （diabetic C＋ D group）（P 〈 0.05）. These findings suggest that these two hormones might potentially improve various bone properties.

关键词： type 1 diabetes mellitus mandibular bone structure mandibular bone formation micro-computed tomography bone histomorphometry

Thermoresponsive dendronized copolymers for protein recognitions based on biotin-avidin interaction

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Chinese Chemical Letters 2017年第4期28卷 832-838页

作者： Chunhua Zhou mona A.Abdel-Rahman Wen Li Kun Liu Afang Zhang Department of Polymer Materials Shanghai University Chemistry Department Polymer Lab.109Faculty of ScienceAssiut University

Thermoresponsive biotinylated dendronized copolymers carrying dendritic oligoethylene glycol（OEG）pendants were prepared via free radical polymerization,and their protein recognitions based on biotin-avidin interaction *** first（PG1） and second generation（PG2） dendronized copolymers were designed to examine possible thickness effects on the interaction between biotin and *** from the outstanding thermoresponsive properties from OEG dendrons,these biotinylated cylindrical copolymers show characteristic thermoresponsive behavior which provides an envelope to capture avidin through switching temperatures above or below their phase transition temperatures（T_（cp）s）.Thus,the recognition of polymer-supported biotin with avidin was investigated with UV/vis spectroscopy and dynamic laser light *** contrast to the case for PG1,the increased thickness for copolymer PG2 hinders partially and inhibits the recognition of biotin moieties with avidin either below or above its T_（cp）.This demonstrates the significant architecture effects from dendronized polymers on the biotin moieties to shift onto periphery of the collapsed aggregates,which should be a prerequisite for protein *** kinds of novel thermoresponsive copolymers may pave a way for the interesting biological applications in areas such as reversible activity control of enzyme or proteins,and for controlled delivery of drugs or genes.

关键词： Dendronized copolymers Dendrimers Thermoresponsive polymers Protein recognition Biotin-avidin interaction Supramolecular chemistry

Seismic attenuation relationship with homogeneous and heterogeneous prediction-error variance models

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Earthquake Engineering and Engineering Vibration 2014年第1期13卷 1-11页

作者： He-Qing Mu Rong-Rong Xu ka-Veng Yuen Faculty of Science and Technology University of Macao

Peak ground acceleration(PGA) estimation is an important task in earthquake engineering *** of the most well-known models is the Boore-Joyner-Fumal formula,which estimates the PGA using the moment magnitude,the site-to-fault distance and the site foundation *** the present study,the complexity for this formula and the homogeneity assumption for the prediction-error variance are investigated and an effi ciency-robustness balanced formula is *** this purpose,a reduced-order Monte Carlo simulation algorithm for Bayesian model class selection is presented to obtain the most suitable predictive formula and prediction-error model for the seismic attenuation *** this approach,each model class(a predictive formula with a prediction-error model) is evaluated according to its plausibility given the *** one with the highest plausibility is robust since it possesses the optimal balance between the data fi tting capability and the sensitivity to noise.A database of strong ground motion records in the Tangshan region of China is obtained from the China Earthquake Data Center for the *** optimal predictive formula is proposed based on this *** is shown that the proposed formula with heterogeneous prediction-error variance is much simpler than the attenuation model suggested by Boore,Joyner and Fumal(1993).

关键词： Bayesian inference Boore-Joyner-Fumal formula heterogeneity variance input-dependent variance model class selection peak ground acceleration seismic attenuation

Terminology Standardization in Chinese Medicine:The Perspective from UCLA Center for East-West Medicine (Ⅱ)

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Chinese Journal of Integrative Medicine 2007年第1期13卷 152-155页

作者： ka-Kit Hui Sonya Pritzker Center for East-West Medicine at UCLA USA.

Center staff and faculty below provide their commentary and perspective on the two major issues （single standards versus plural terms and the basis for standards） comprising the terminology standardization debate as outlined by Sonya Pritzker above. Where most or all members of the discussion agree, that perspective is summarized. Members with distinct or outstanding positions on an issue are offered the opportunity to describe their viewpoint in their own words.

关键词： Terminology Standardization in Chinese Medicine West UCLA

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Martin boundary and exit space on the Sierpinski gasket

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Science China Mathematics 2012年第3期55卷 475-494页

作者： LAU ka-Sing NGAI Sze-Man Department of Mathematics The Chinese University of Hong Kong Department of Mathematical Sciences Georgia Southern University

We define a new Markov chain on the symbolic space representing the Sierpinski gasket (SG),and show that the corresponding Martin boundary is homeomorphic to the SG while the minimal Martin boundary is the three vertices of the *** addition,the harmonic structure induced by the Markov chain coincides with the canonical one on the *** suggests another approach to consider the existence of Laplacians on those self-similar sets for which the problem is still not settled.

关键词： Martin boundary Markov chain Green function harmonic function fractal Sierpinski gasket