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highly catalytic metal–organic framework coating enabled by liquid superwetting and confinement

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Nano Research 2023年第5期16卷 7716-7723页

作者： Bo yi yan-Lung wong Kedi li Changshun hou Tengrui Ma zhengtao Xu Xi yao Department of Biomedical Sciences City University of Hong KongHong Kong 999077China Department of Chemistry City University of Hong KongHong Kong 999077China Institute of Materials Research and Engineering Agency for ScienceTechnology and Research(A*STAR)Singapore 138634Singapore City University of hong Kong Shenzhen Research Institute Shenzhen 518057China

In this work,we report that high catalytic performance of metal–organic frameworks(MOFs)can be obtained through a synergistic effect of postsynthetic modification of MOF nanoparticles and liquid superwetting and confinement in the MOF ***,2-ureido-4[1h]pyrimidinone(UPy)functionalized polysiloxanes were covalently appended onto the UiO-66 nanoparticles via a postsynthetic approach,which were further anchored onto different porous films through multivalent hydrogen bonding of the UPy *** hydrophobic MOF coating can preserve the porosity of the solid substrates,enable rapid liquid superwetting and confinement within the porous *** the Knoevenagel condensation as a modeled system,robust and highly catalytic performances of the MOF coating were observed on a range of aldehyde ***-scale production of chromene,a pharmaceutical which is typically synthesized via expensive catalysis,was successfully demonstrated on the MOF coating with high yielding rates,demonstrating the great potential of the MOF coating in pharmaceutical synthesis.

关键词： metal–organic framework postsynthetic modification hydrogen bonding superwetting liquid confinement

Determining h0 using a model-independent method

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Frontiers of physics 2017年第1期12卷 133-140页

作者： Pu-Xun Wu zheng-Xiang li hong-Wei yu Center for Nonlinear Science and Department of Physics Ningbo University Ningbo 315211 China Center for high Energy Physics Peking University Beijing 100080 China Department of Astronomy Beijing Normal University Beijing 100875 China

By using type Ia supernovae （SNIa） to provide the luminosity distance （LD） directly, which depends on the value of the hubble constant h0 = 100h km·s^-1· Mpc^-1, and the angular diameter distance from galaxy clusters or baryon acoustic oscillations （BAOs） to give the derived LD according to the distance duality relation, we propose a model-independent method to determine h from the fact that different observations should give the same LD at a given redshift. Combining the Sloan Digital Sky Survey II （SDSS-II） SNIa from the MLCS2k2 light curve fit and galaxy cluster data, we find that at the 1σ confidence level （CL）, h = 0.5867±0.0303 for the sample of the elliptical β model for galaxy clusters, and h = 0.6199± 0.0293 for that of the spherical β model. The former is smaller than the values from other observations, whereas the latter is consistent with the Planck result at the 2σ CL and agrees very well with the value reconstructed directly from the h（z） data. With the SDSS-II SNIa and BAO measurements, a tighter constraint, h = 0.6683 ± 0.0221, is obtained. For comparison, we also consider the Union 2.1 SNIa from the SALT2 light curve fitting. The results from the Union 2.1 SNIa are slightly larger than those from the SDSS-II SNIa, and the Union 2.1 SNIa ＋ BAOs give the tightest value. We find that the values from SNIa ＋ BAOs are quite consistent with those from the Planck and the BAOs, as well as the local measurement from Cepheids and very-low-redshift SNIa.

关键词： hubble constant luminosity distance angular diameter distance

Removal of Lead from Aqueous Solution by Acinetobacter calcoaceticus

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Biomedical and Environmental Sciences 1990年第2期3卷 202-210页

作者： N.K.MAK y.K.MOK V.W.D.ChUI M.h.wong Department of Biology Hong Kong Baptist College 224 Waterloo Road Hong Kong

A bacterial strain tolerant to the presence of 400 ppm lead was isolated from digested sewage sludge. The organism was identified as Acinetobacter calcoaceticus var: anitraus (98% confidence). Both viable and formalin-inactivated bacterial cells could remove Pb from an aqueous solution. The Pb-binding ability of inactivated cells was compared with that of a commercial ion-exchange resin, Amberlite IR-I20. The metal-binding ability of A. calcoaceticus followed the sequence Pb≥Cu≥Cr≥ (Cd, Ni, and Zn)≥Co. The ability of the inactivated cells to remove Pb was ph sensitive, and the adsorption process was slightly affected at high temperature (70℃). The adsorption and desorption process worked equally well with A. calcoaceticus embedded in a polyacrylamide gel matrix. (c)1990 Academic Press, Inc.

关键词： Pb

hybrid optical parametrically-oscillating emitter at 1930 nm for volumetric photoacoustic imaging of water content

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elight 2022年第1期2卷 68-74页

作者： Jiawei Shi Mingsheng li huajun Tang Jiqiang Kang Najia Sharmin Amir Rosenthal Kenneth K.y.wong Department of Electrical and Electronic Engineering The University of Hong Kong Pokfulam RoadHong KongChina.2 Department of Electrical EngineeringTechnion–Israel Institute of TechnologyTechnion City32000 HaifaIsrael Advanced Biomedical Instrumentation Centre Hong Kong Science ParkShatinNew TerritoriesHong KongChina

Water plays a vital role in biological metabolism and it would be essential to trace the water content non-invasively,such as leveraging the vibrational absorption peak of the O-h ***,due to the lack of an efficient laser source,it was challenging to image the water content in the deep tissue with micron-level spatial *** address this problem,we develop a high-power hybrid optical parametrically-oscillating emitter(hOPE)at 1930 nm,at which the vibrational absorption peak of the O-h bond *** maximum pulse energy is over 1.74μJ with a pulse repetition rate of 50 khz and a pulse width of 15 *** employ this laser source in the optical-resolution photoacoustic microscopy(OR-PAM)system to image the water content in the phantom and the biological tissue in *** 1930-nm OR-PAM could map the water content in the complex tissue environment at high spatial resolution,deep penetration depth,improved sensitivity,and suppressed artifact signal of the lipid.

关键词： Fiber optical parametric oscillator Thulium-doped fiber laser Photoacoustic microscopy

Risk stratification in symptomatic intracranial atherosclerotic disease with conventional vascular risk factors and cerebral haemodynamics

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Stroke & Vascular Neurology 2023年第1期8卷 77-85页

作者： Xuan Tian hui Fang linfang Lan hing Lung Ip Jill Abrigo haipeng liu lina zheng Florence S y Fan Sze ho Ma Bonaventure Ip Bo Song yuming Xu Jingwei li Bing Zhang yun Xu yannie O y Soo Vincent Mok Ka Sing wong Thomas W Leung Xinyi Leng Department of Medicine and Therapeutics The Chinese UniversityHong KongChina Department of Neurology The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenanChina Department of Neurology The First Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdongChina Department of Imaging and Interventional The Chinese UniversityHong KongChina Research Centre of Intelligent healthcare Faculty of Health and Life ScienceCoventry UniversityCoventryUK Department of Neurology Nanjing University Medical School Affiliated Nanjing Drum Tower HospitalNanjingJiangsuChina Department of Radiology Nanjing University Medical School Affiliated Nanjing Drum Tower HospitalNanjingJiangsuChina

Background and purpose Symptomatic intracranial atherosclerotic stenosis(sICAS)is associated with a considerable risk of recurrent stroke despite contemporarily optimal medical *** of luminal stenosis in sICAS and its haemodynamic significance quantified with computational fluid dynamics(CFD)models were associated with the risk of stroke *** aimed to develop and compare stroke risk prediction nomograms in sICAS,based on vascular risk factors and these *** Patients with 50%-99%sICAS confirmed in CT angiography(CTA)were *** vascular risk factors were *** of luminal stenosis in sICAS was dichotomised as moderate(50%-69%)and severe(70%-99%).Translesional pressure ratio(PR)and wall shear stress ratio(WSSR)were quantified via CTA-based CFD modelling;the haemodynamic status of sICAS was classified as normal(normal PR&WSSR),intermediate(otherwise)and abnormal(abnormal PR&WSSR).All patients received guideline-recommended medical *** developed and compared performance of nomograms composed of these variables and independent predictors identified in multivariate logistic regression,in predicting the primary outcome,recurrent ischaemic stroke in the same territory(SIT)within 1 *** Among 245 sICAS patients,20(8.2%)had *** D2h2A nomogram,incorporating diabetes,dyslipidaemia,haemodynamic status of sICAS,hypertension and age≥50 years,showed good calibration(P for hosmer-Lemeshow test=0.560)and discrimination(C-statistic 0.73,95%CI 0.60 to 0.85).It also had better performance in risk reclassification and provided larger net benefits in decision curve analysis,compared with nomograms composed of conventional vascular risk factors only,and plus the severity of luminal stenosis in *** analysis in patients with anterior-circulation sICAS showed similar *** The D2h2A nomogram,incorporating conventional vascular risk factors and the haemodynamic significance of sICAS a

关键词： intracranial otherwise stratification

Low-field, high-gradient NMR shows diffusion contrast consistent with localization or motional averaging of water near surfaces

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Magnetic Resonance Letters 2023年第2期3卷 90-107,I0003页

作者： Nathan h.Williamson Velencia J.Witherspoon teddy X.Cai Rea Ravin Ferenc horkay Peter J.Basser Eunice Kennedy Shriver National Institute of Child health and human Development National Institutes of HealthBethesdaMD20892USA Wellcme Centre for Igative Neuromging FMRIBNuffeld Department of Clinical NeurosciencesUiversity of Oxford Oxford OX39DUUK Celoptics RockvilleMD20850USA

Nuclear magnetic resonance(NMR)measurements of water diffusion have been extensively used to probe microstructure in porous materials,such as biological tissue,however primarily using pulsed gradient spin echo(PGSE)***-field single-sided NMR systems have built-in static gradients(SG)much stronger than typical PGSE maximum gradient strengths,which allows for the signal attenuation at extremely high b-values to be ***,we perform SG spin echo(SGSE)and SG stimulated echo(SGSTE)diffusion measurements on biological cells,tissues,and *** on fixed and live neonatal mouse spinal cord,lobster ventral nerve cord,and starved yeast cells all show multiexponential signal attenuation on a scale of b with significant signal fractions observed at b×Do>1 with b as high as 400 ms/*** persistent signal fractions trend with surface-to-volume ratios for these systems,as expected from porous media *** exception found for the case of fixed *** spinal cords was attributed to faster exchange or permeability in live spinal cords than in fixed spinal cords on the millisecond *** suggests the existence of multiple exchange processes in neural tissue,which may be relevant to the modeling of time-dependent diffusion in gray *** observed multi-exponential attenuation is from protons on water and not macromolecules because it remains proportional to the normalized signal when a specimen is washed with *** signal that persists to b×Do>1 is also drastically reduced after delipidation,indicating that it originates from lipid membranes that restrict water *** multiexponential or stretched exponential character of the signal attenuation at b×Do>1 appears mono-exponential when viewed on a scale of(b×Do)/3,suggesting it may originate from localization or motional averaging of water near membranes on sub-micron length *** try to disambiguate these two contributions,signal attenuation curves were compared at varying temper

关键词： Magnetic resonance in porous media Single-sided NMR-MOUSE Microstructure high b-values Short diffusion time Stretched exponential Diffusion MRI contrast mechanisms

G protein-coupled receptors in neurodegenerative diseases and psychiatric disorders

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Signal Transduction and Targeted Therapy 2023年第6期8卷 2493-2549页

作者： Thian-Sze wong Guangzhi li Shiliang li Wei Gao Geng Chen Shiyi Gan Manzhan Zhan honglin li Song Wu yang Du Kobilka Institute of Innovative Drug Discovery Shenzhen Key Laboratory of Steroid Drug Discovery and DevelopmentSchool of MedicineThe Chinese University of Hong Kong518172ShenzhenGuangdongChina School of Medicine Tsinghua University100084BeijingChina Institute of Urology The Affiliated Luohu Hospital of Shenzhen UniversityShenzhen University518000ShenzhenGuangdongChina Shanghai Key Laboratory of New Drug Design School of PharmacyEast China University of Science and Technology200237ShanghaiChina Innovation Center for AI and Drug Discovery East China Normal University200062ShanghaiChina Department of Urology South China HospitalHealth Science CenterShenzhen University518116ShenzhenGuangdongChina

Neuropsychiatric disorders are multifactorial disorders with diverse aetiological *** treatment targets is challenging because the diseases are resulting from heterogeneous biological,genetic,and environmental ***,the increasing understanding of G protein-coupled receptor(GPCR)opens a new possibility in drug *** our knowledge of molecular mechanisms and structural information of GPCRs will be advantageous for developing effective *** review provides an overview of the role of GPCRs in various neurodegenerative and psychiatric ***,we highlight the emerging opportunities of novel GPCR targets and address recent progress in GPCR drug development.

关键词： psychiatric disorders diseases

Trap Behaviors of Constant Electric Field Stressing in Thin Oxynitride and Re-oxidized Oxynitride Films

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Chinese Physics Letters 1992年第9期9卷 479-482页

作者： yANG Bingliang liU Baiyong h.wong y.C.Cheng Department of Applied Physics South China University of TechnologyGuangzhou 510641 Department of Electronic Engineering City Polytechnic of hong Kong Tat Chee Avenue KowloonHong Kong

The behaviors of constant electric field stressing of the thin(200Å)oxynitride and re-oxidized oxynitride films are *** flat-band shift is not a simple function of the stressing *** observed phenomena are attributed to the significance of trap filling,electronic tunneling and trap generation at different stressing field ***-oxidized sample is found to have high resistant to the electron tunneling and trap generation.

关键词： field oxidized tunneling

Removal of Cu and Ni by Free and Immobilized Microalgae

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Biomedical and Environmental Sciences 1992年第2期5卷 99-108页

作者： M.h.wong D.C.h.PAK Department of Biology Hong Kong Baptist College 224 Waterloo Road KowloonDepartment of Biology Hong Kong Baptist College 224 Waterloo Road Kowloon Hong KongHong Kong

The present investigation evaluated the effectiveness of Chlorella cells in concentrating Cu and Ni in their cells and thereby removing the two metals from solution. The removal efficiency of the two metals by free and immobilized algal cells were further studied. (1) Four types of Chlorella cells, namely Chlorella pyrenoidosa (26) (from Carolina Biological Supplies Company), Chlorella hKBC-1 and-2 (isolated from a polluted stream receiving wastewater from several electroplating factories) and Chlorella hKBC-3 (from a clean water pond) were subjected to different concentrations of Cu and Ni accordingly. It was revealed that Chlorella hKBC-1 was the most tolerant species toCu and Ni as reflected by their highest values of 48 h and 96 h 'highest no effect concentrations' (The highest concentration of the tested substance that does not inhibit the growth rate of the alga: Cu 2 and Ni 10 mg/1 at 48 h, Cu 2 and Ni 5 at 96 h). This was followed by C. pyrenoidosa (26) and then C. hKBC-2 while C. hKBC-3 had the lowest tolerance to the two metals (Cu 0.5 and Ni 2 at 48 h; Cu 0.5 and Ni 1 mg/1 at 96 h). (2) It was further revealed that C. hKBC-1 had higher concentration factors and removal efficiencies of Ni (734-963 mg/1, 16.3-18.7%) and C. hKBC-2 had higher concentration factors and removal efficiencies of Cu (2316-2839 mg/1, 53.7-66%) when exposed to lower concentrations of Cu (0.5,1 and 2 mg/1) and Ni (5, 10 and 13 mg/1). (3) By treating the free and immobilized algal cells (algal cells entrapped in alginate beads) with different concentrations of Cu and Ni, it was observed that free cells had higher concentration factors and removal efficiencies when compared with immobilized cells (free cells: Cu 1577-3056 mg/1, 24.2-71.4%; Ni 355-849 mg/1, 4.8-18.7%; immobilized cells: Cu 453-935 mg/1, 13.9-53.2%; Ni 244-486 mg/1, 3.2-11.9%).

关键词： Removal of Cu and Ni by Free and Immobilized Microalgae Cu Ni