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Performance of ground penetrating radar in root detection and its application in root diameter estimation under controlled conditions

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Science China Earth Sciences 2016年第1期59卷 145-155页

作者： yeung shan wing YAN Wai Man HAU Chi Hang Billy Department of Civil Engineering The University of Hong Kong Kadoorie Institute The University of Hong Kong

A plant is stabilized by its root system. In congested urban cities such as Hong Kong, ground trenching is frequently seen due to the installation of utility lines along the roadside. Soil nailing, which involves soil coring in slopes, is a common solution to improve the slope stability. However, both activities inevitably pose a risk to the integrity of any root sys- tems present, and thus reduce the root anchorage. To prevent or minimize such damage, a careful design of the excava- tion/drilling location is of prime importance. Ground penetrating radar （GPR） provides a non-destructive method for locating roots by examining the contrast between the dielectric properties of the roots and the surrounding soil. To examine the perfor- mance of GPR and promote its use in Hong Kong, a test bed was prepared using local materials to create a controlled envi- ronment in which to conduct a series of systematic tests evaluating the performance of a 900 MHz GPR. The reflected radar- grams were subject to the influence of the following factors： size and depth of roots, horizontal distance between roots, and contrast between the root and soil water content. Correlations between root size and a number of waveform parameters were also explored. Limiting values for root size, root embedded depth, horizontal separation distance between roots, and water content contrast between root and soil were obtained. A significant correlation was found between the root diameter and time travel parameter T2 （p〈0.001, t=0.795）. Because GPR root detection is highly site-specific, this study provides a local refer- ence for GPR performance in the Hong Kong environment. The findings demonstrate that the 900 MHz GPR is applicable in Hong Kong for the detection of main roots.

关键词： GPR Radar profile Root detection Root water content Root size

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SHAPE MEMORY EFFECT OF PU IONOMERS WITH IONIC GROUPS ON HARD-SEGMENTS

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Chinese Journal of Polymer Science 2006年第2期24卷 173-186页

作者：胡金莲 Kwok-wing yeung Institute of Textiles and Clothing Hong Kong Polytechnic University Hung HomHong KongChina

SMPU （shape memory polyurethane） non-ionomers and ionomers, synthesized with poly（c-caprolactone）（PCL）, 4, 4＇-diphenylmethane diisocyanate （MDI）, 1,4-butanediol （BDO）, dimethylolpropionic acid （DMPA） were measured with cyclic tensile test and strain recovery test. The relations between the structure and shape memory effect of these two series were studied with respect to the ionic group content and the effect of neutralization. The resulting data indicate that, with the introduction of asymmetrical extender, the stress at 100% elongation is decreased for PU non-ionomer and ionomer series, especially lowered sharply for non-ionomer series; the fixation ratio of ionomer series is not affected obviously by the ionic group content; the total recovery ratio of ionomer series is decreased greatly. After sufficient relaxation time for samples stretched beforehand, the switching temperature is raised slightly, whereas the recovery ratio measured with strain recovery test method is lowered with increased DMPA content. The characterization with FT-IR, DSC, DMA elucidated that, the ordered hard domain of the two series is disrupted with the introduction of DMPA which causes more hard segments to dissolve in soft phase; ionic groups on hard segment enhance the cohesion between hard segments especially at high ionic group content and significantly facilitate the phase separation compared with the corresponding non-ionomer at moderate ionic group content.

关键词： Polyurethane Ionomers Cyclic thermo-mechanical investigations Shape memory effect Cyclic tensile test Strain recovery test.

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A novel reductive ring-opening reaction of isoxazolidine to form functionalized 1,3-aminoalcohol

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Chinese Chemical Letters 2007年第6期18卷 629-632页

作者： wing Hong Chan Albert W.M. Lee Wai yeung Wong Department of Chemistry Hong Kong Baptist University Kowloog Tong Hong Kong

Reductive cleavage of the NO bond of isoxazolidine ring with catalytic hydrogenation over Raney nickel was described. Bicyclic isoxazolidines could be effectively converted into the corresponding 1,3-amino-alcohol possessing a sultone or sultam moiety with high conversion and yield when the hydrogenation was catalyzed by freshly prepared Raney nickel under a pressure of 40 psi in the presence of triethylamine.

关键词： Isoxazolidine Hydrogenation Raney nickel 1,3-Amino-alcohol

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THE ANALYTICAL SOLUTION FOR SEDIMENT REACTION AND DIFFUSION EQUATION WITH GENERALIZED INITIAL-BOUNDARY CONDITIONS

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Applied Mathematics and Mechanics(English Edition) 2001年第4期22卷 404-408页

作者： XIONG Yue-shan(熊岳山) Wai wing-hong(韦永康) Department of Computer Science National University of Science and Technology Changsha 410073 P R China Department of Civil and Structural Engineering The Hong Kong Polytechnic University Hung Hom Kowloon Hong Kong P R China

The sediment reaction and diffusion equation,with generalized initial mid boundary condition is studied. By using Laplace transform and Jordan lemma, an analytical solution is got,,which is an extension of analytical solution provided by Cheng Kwokming James ( only diffusion was considered in analytical solution of Cheng). Some problems arisen in the computation of analytical solution formula are also analysed.

关键词： sediment reaction diffusion analytical solution

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Acupuncture for low back pain:a clinical practice guideline from the Hong Kong taskforce of standardized acupuncture practice

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Journal of Traditional Chinese Medicine 2022年第1期42卷 140-147页

作者： CHEN Haiyong yeung wing-Fai YANG Mingxiao MU Jinglan ZIEA Tat-Chi NG Bacon Fung-Leung LAO Lixing School of Chinese Medicine University of Hong KongHong Kong SARChina School of Nursing Hong Kong Polytechnic UniversityHong Kong SARChina Bendheim Integrative Medicine Center Memorial Sloan Kettering Cancer Center1429 First AvenueNew York 10021USA Department of Anesthesiology Nanjing Drum Tower HospitalNanjing University Medical SchoolNanjing210008China Chinese Medicine Department Hong Kong Hospital AuthorityHong Kong SARChina Virginia University of Integrative Medicine FairfaxVA 22031USA

OBJECTIVE:To develop a clinical practice guideline to guide the treatment of low back pain by ***:An integrative approach of systematic review of literature,clinical evidence classification,expert opinion surveying,and consensus establishing via a Delphi program was utilized during the developing *** evidence-based practice standards and the personalized features of acupuncture were taken into ***:Based on clinical evidence and expert opinions,we developed a clinical practice guideline for the treatment of low back pain with *** recommendations have a wide coverage spanning from Western Medicine diagnosis and Traditional Chinese Medicine syndrome differentiation,to acupuncture treatment procedures,as well as post treatment care for rehabilitation and *** recommendations for acupuncture practice included treatment principles,therapeutic regimens,and operational *** levels of evidence and strength of recommendation were rated for each procedure of ***:A clinical practice guideline for acupuncture treating low back pain was developed based on contemporary clinical evidence and experts'consensus to provide best currently agreeable practice guideline for domestic and international stakeholders.

关键词： acupuncture low back pain diagnosis syndrome differentiation rehabilitation practice guideline

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Solvent-Assisted Supramolecular Assembly of Cyclotetrasiloxane– Functionalized Alkynylplatinum(II) Terpyridine Complexes

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CCS Chemistry 2019年第5期1卷 464-475页

作者： Ho-Leung Au-yeung Sammual Yu-Lut Leung Vivian wing-Wah Yam and Department of Chemistry The University of Hong KongPokfulam RoadHong KongChina

Our present study demonstrated and explored the solvent effects on the association mechanism of the supramolecular nanomaterials in a series of cyclo-tetrasiloxane-appended alkynylplatinum(II)terpyri-dine *** the delicate balance of molecular interactions,some of these complexes were found to exhibit molecular association prop-erties,with possible morphological transformation in response to solvent polarities.

关键词： supramolecular cyclotetrasiloxane plati-num solvent effects hydrophobic interaction nanomaterial metal-metal interactions noncova-lent interaction supramolecular polymerization mechanism

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Verification of tropical cyclones(TC)wind structure forecasts from global NWP models and ensemble prediction systems(EPSs)

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Tropical Cyclone Research and Review 2022年第2期11卷 88-102页

作者： Xiaoqin Lu Wai Kin Wong Kin Chung Au-yeung Chun wing Choy Hui Yu shanghai Typhoon Institute and Laboratory of Typhoon Forecast Technique China Meteorological AdministrationShanghaiChina Hong Kong Observatory Hong KongChina

Forecasting wind structure of tropical cyclone(TC)is vital in assessment of impact due to high winds using Numerical Weather Prediction(NWP)*** usual verification technique on TC wind structure forecasts are based on grid-to-grid comparisons between forecast field and the actual ***,precision of traditional verification measures is easily affected by small scale errors and thus cannot well discriminate the accuracy or effectiveness of NWP model *** this study,the Method for Object-Based Diagnostic Evaluation(MODE),which has been widely adopted in verifying precipitation fields,is utilized in TC’s wind field verification for the first *** TC wind field forecast of deterministic NWP model and Ensemble Prediction System(EPS)of the European Centre for Medium-Range Weather Forecasts(ECMWF)over the western North Pacific and the South China Sea in 2020 were evaluated.A MODE score of 0.5 is used as a threshold value to represent a skillful(or good)*** is found that the R34(radius of 34 knots)wind field structure forecasts within 72 h are good regardless of DET or *** performance of R50 and R64 is slightly worse but the R50 forecasts within 48 h remain good,with MODE exceeded *** R64forecast within 48 h are worth for reference as well with MODE of around *** study states that the TC wind field structure forecast by ECMWF is skillful for TCs over the western North Pacific and the South China Sea.

关键词： Verification Tropical cyclones wind structure forecasts Numerical weather prediction models Ensemble prediction system

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Modulatory effect of International standard Scalp Acupuncture on brain activation in the elderly as revealed by resting-state fMRI

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Neural Regeneration Research 2019年第12期14卷 2126-2131页

作者： Wai-yeung Chung Song-Yan Liu Jing-Chun Gao Yi-Jing Jiang Jing Zhang shan-shan Qu Ji-Ping Zhang Xiao-Long Tan Jun-Qi Chen Sheng-Xu Wang School of Traditional Chinese Medicine Southern Medical University Guangzhou Guangdong Province China School of Chinese Medicine The Chinese University of Hong Kong Shatin Hong Kong Special Administrative Region China Department of Neurology China-Japan Union Hospital of Jilin University Changchun Jilin Province China Department of Rehabilitation Medicine Third Affiliated Hospital of Southern Medical University Guangzhou Guangdong Province China Department of Rehabilitation Medicine Rehabilitation Hospital Fujian University of Traditional Chinese Medicine Fuzhou Fujian Province China Department of Medical Image Third Affiliated Hospital of Southern Medical University Guangzhou Guangdong Province China

The specific mechanisms by which acupuncture affects the central nervous system are unclear. In the International Standard Scalp Acupuncture system, acupuncture needles are applied at the middle line of the vertex, anterior parietal-temporal oblique line, and the posterior parietal-temporal oblique line. We conducted a single-arm prospective clinical trial in which seven healthy elderly volunteers (three men and four women;50–70 years old) received International Standard Scalp Acupuncture at MS5 (the mid-sagittal line between Baihui (DU20) and Qianding (DU21)), the left MS6 (line joining Sishencong (EX-HN1) and Xuanli (GB6)), and the left MS7 (line joining DU20 and Qubin (GB7)). After acupuncture, resting-state functional magnetic resonance imaging demonstrated changes in the fractional amplitude of low frequency fluctuations and regional homogeneity in various areas, showing remarkable enhancement of regional homogeneity in the bilateral anterior cingulate, left medial frontal gyrus, supramarginal gyrus, right middle frontal gyrus, and inferior frontal gyrus. Functional connectivity based on a seed region at the right middle frontal gyrus (42, 51, 9) decreased at the bilateral medial superior frontal gyrus. Our data preliminarily indicates that the international standard scalp acupuncture in healthy elderly participants specifcally enhances the correlation between the brain regions involved in cognition and implementation of the brain network regulation system and the surrounding adjacent brain regions. The study was approved by the Ethics Committee of the China-Japan Union Hospital at Jilin University, China, on July 18, 2016 (approval No. 2016ks043).

关键词： nerve regeneration resting-state functional magnetic resonance imaging International Standard Scalp Acupuncture acupoint specificity brain functional connectivity healthy elderly volunteers low frequency fluctuation regional homogeneity functional connectivity neural regeneration

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A new osteogenic protein isolated from Dioscorea opposita Thunb accelerates bone defect healing through the mTOR signaling axis

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Bioactive Materials 2023年第9期27卷 429-446页

作者： John Akrofi Kubi Augustine Suurinobah Brah Kenneth Man Chee Cheung Yin Lau Lee Kai-Fai Lee Stephen Cho wing Sze Wei Qiao Kelvin Wai-Kwok yeung Department of Orthopaedics and Traumatology Li Ka Shing Faculty of MedicineThe University of Hong Kong(HKU)Hong Kong S.A.R.PR China Shenzhen Key Laboratory for Innovative Technology in Orthopaedic Trauma HKU-Shenzhen HospitalShenzhen518053PR China Department of Obstetrics and Gynaecology Li Ka Shing Faculty of MedicineHKU21 Sassoon RoadHong Kong S.A.RPR China Shenzhen Key Laboratory of Fertility Regulation Reproductive Medicine CenterHKU-Shenzhen HospitalShenzhenPR China Department of Biology Faculty of ScienceHong Kong Baptist UniversityKowloon TongHong Kong S.A.RPR China Golden Meditech Center for NeuroRegeneration Sciences Hong Kong Baptist UniversityKowloon TongHong Kong S.A.RPR China Applied Oral Sciences and Community Dental Care Faculty of DentistryHong Kong S.A.RPR China

Delayed bone defect repairs lead to severe health and socioeconomic impacts on patients. Hence, there are increasing demands for medical interventions to promote bone defect healing. Recombinant proteins such as BMP-2 have been recognized as one of the powerful osteogenic substances that promote mesenchymal stem cells (MSCs) to osteoblast differentiation and are widely applied clinically for bone defect repairs. However, recent reports show that BMP-2 treatment has been associated with clinical adverse side effects such as ectopic bone formation, osteolysis and stimulation of inflammation. Here, we have identified one new osteogenic protein, named ‘HKUOT-S2’ protein, from Dioscorea opposita Thunb. Using the bone defect model, we have shown that the HKUOT-S2 protein can accelerate bone defect repair by activating the mTOR signaling axis of MSCs-derived osteoblasts and increasing osteoblastic biomineralization. The HKUOT-S2 protein can also modulate the transcriptomic changes of macrophages, stem cells, and osteoblasts, thereby enhancing the crosstalk between the polarized macrophages and MSCs-osteoblast differentiation to facilitate osteogenesis. Furthermore, this protein had no toxic effects in vivo. We have also identified HKUOT-S2 peptide sequence TKSSLPGQTK as a functional osteogenic unit that can promote osteoblast differentiation in vitro. The HKUOT-S2 protein with robust osteogenic activity could be a potential alternative osteoanabolic agent for promoting osteogenesis and bone defect repairs. We believe that the HKUOT-S2 protein may potentially be applied clinically as a new class of osteogenic agent for bone defect healing.

关键词： Dioscorea spp protein Mesenchymal stem cells(MSCs) Osteoblast differentiation Bone mineral density(BMD) Bone defect repair mTOR signaling pathway

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A MULTIPLE INTELLIGENT AGENT SYSTEM FOR CREDIT RISK PREDICTION VIA AN OPTIMIZATION OF LOCALIZED GENERALIZATION ERROR WITH DIVERSITY

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Journal of Systems Science and Systems Engineering 2007年第2期16卷 166-180页

作者： Daniel S. yeung wing W. Y. NG Aki P. F. CHAN Patrick P. K. CHAN Michael FIRTH Eric C. C. TSANG Media and Life Science Computing Laboratory Shenzhen Graduate School Harbin Institute of Technology Shenzhen 518055 China Department of Computing Hong Kong Polytechnic University Hong Kong China Department of Finance and Insurance Lingnan University Hong Kong

Company bankruptcies cost billions of dollars in losses to banks each year. Thus credit risk prediction is a critical part of a bank＇s loan approval decision process. Traditional financial models for credit risk prediction are no longer adequate for describing today＇s complex relationship between the financial health and potential bankruptcy of a company. In this work, a multiple classifier system （embedded in a multiple intelligent agent system） is proposed to predict the financial health of a company. In our model, each individual agent （classifier） makes a prediction on the likelihood of credit risk based on only partial information of the company. Each of the agents is an expert, but has limited knowledge （represented by features） about the company. The decisions of all agents are combined together to form a final credit risk prediction. Experiments show that our model out-performs other existing methods using the benchmarking Compustat American Corporations dataset.

关键词： Credit rating business intelligence localized generalization error multiple classifier system feature grouping

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