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Perspective on the relationship between microbiota dysbiosis and neuroinflammation:probiotics as a treatment option

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Neural Regeneration Research 2022年第9期17卷 1969-1970页

作者： Chiao W.ng Zahoor A.Shah Department of Medicinal and Biological Chemistry College of Pharmacy and Pharmaceutical SciencesUniversity of ToledoToledoOHUSA

Introduction:In the 1680s,Antonie van Leewenhoek was the first to observe the differences in the human gut microbiome versus the oral cavity diversity,and it led to the birth of a new term,“microbiota”.Later,the link between the brain and the gut was observed to be facilitated by the vagus nerve,allowing for neurotransmitters secreted in the gastrointestinal tract to travel to the brain,directing signals that influence brain *** gut microbiome is linked to various diseases ranging from autism spectrum disorder to Parkinson’s disease(PD)and is projected to be the new“disease-causing mechanism,”calling for interventions that can modulate gut microbiota and mitigate brain *** dysbiosis is observed before and after the onset of various neurodegenerative diseases and often manifests itself into gut-related diseases such as.

关键词： inflammation diseases treatment

Positron-Lithium Atom and Electron-Lithium Atom Scattering Systems at Intermediate and High Energies

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Chinese Physics Letters 2006年第7期23卷 1753-1756页

作者： K. Ratnavelu S. Y. ng Institute of Mathematical Sciences Faculty of Science University of Malaya 50603 Kuala Lumpur Malaysia Department of Physics Faculty of Science National University of Singapore Singapore

The coupled-channel optical method is used to study positron scattering by atomic lithium at energies ranging from the ionization threshold to 60eV, The present method simultaneously treats the target channels and the positronium （Ps） channels in the coupled-channel method together with the continuum effects via an ab-initio optical potential. Ionization, elastic and inelastic cross sections in target channels, and the total cross section are also reported and compared with other theoretical and experimental data. A comparative study with the corresponding electron-lithium data is also reported.

关键词： CLOSE-COUPLIng THEORY HYDROGEN SCATTERIng CROSS-SECTIONS COLLISIONS

Management of difficult intravenous access:a qualitative revie

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World Journal of Emergency Medicine 2022年第6期13卷 467-478页

作者： Mingwei ng Leong Kwok Fai Mark Lateef Fatimah Department of Emergency Medicine Singapore General HospitalSingapore 169608Singapore

BACKGROUND:A perennial challenge faced by clinicians and made even more relevant with the global obesity epidemic,difficult intravenous access(DIVA)adversely impacts patient outcomes by causing significant downstream delays with many aspects of diagnoses and *** most published DIVA strategies are limited to various point-of-care ultrasound techniques while other“tricks-of-the-trade”and pearls for overcoming DIVA are mostly relegated to informal nonpublished material,this article seeks to provide a narrative qualitative review of the iterature on DIVA and consolidate these strategies into a practical ***:We conducted a literature search on PubMed using the keywords“difficult intravenous access”,“peripheral vascular access”and“peripheral venous access”and searched emergency medicine and anaesthesiology resources for relevant *** strategies were then categorized and incorporated into a DIVA ***:We propose a Vortex approach to DIVA that is modelled after the Difficult Airway Vortex concept:starting off with standard peripheral intravenous cannulation(PIVC)techniques,progressing sequentially on to ultrasound-guided cannulation and central venous cannulation and finally escalating to the most invasive intraosseous access should the patient be in extremis or should best efforts with the other lifelines ***:DIVA is a perennial problem that healthcare providers across various disciplines will be increasingly challenged *** is crucial to have a systematic stepwise approach such as the DIVA Vortex when managing such patients and have at hand a wide repertoire of techniques to draw upon.

关键词： Difficult intravenous access Venepuncture Vortex Peripheral intravenous cannulation

Stability and Generalization of Hypergraph Collaborative Networks

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Machine Intelligence Research 2024年第1期21卷 184-196页

作者： Michael K.ng Hanrui Wu Andy Yip Institute of Data Science The University of Hong KongHong KongChina Department of Mathematics The University of Hong KongHong KongChina College of Information Science and Technology Jinan UniversityGuangzhou 510006China

Graph neural networks have been shown to be very effective in utilizing pairwise relationships across ***,there have been several successful proposals to generalize graph neural networks to hypergraph neural networks to exploit more com-plex *** particular,the hypergraph collaborative networks yield superior results compared to other hypergraph neural net-works for various semi-supervised learning *** collaborative network can provide high quality vertex embeddings and hyperedge embeddings together by formulating them as a joint optimization problem and by using their consistency in reconstructing the given *** this paper,we aim to establish the algorithmic stability of the core layer of the collaborative network and provide generaliz--ation *** analysis sheds light on the design of hypergraph filters in collaborative networks,for instance,how the data and hypergraph filters should be scaled to achieve uniform stability of the learning *** experimental results on real-world datasets are presented to illustrate the theory.

关键词： Hypergraphs vertices hyperedges collaborative networks graph convolutional neural networks(CNNs) stability generalization guarantees

Large Eddy Simulation for Plunge Breaker and Sediment Suspension

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China Ocean Engineering 2002年第2期17卷 151-164页

作者：白玉川 C.O.ng Institute of Sediment on River and Coast Engineering Tianjin UniversityTianjin 300072China The State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200062China Department of Mechanical Engineering the University of Hong KongHong KongChina

Breaking waves are a powerful agent for generating turbulence that plays an important role in many fluid dynamical processes, particularly in the mixing of materials. Breaking waves can dislodge sediment and throw it into suspension, which will then be carried by wave-induced steady current and tidal flow. In order to investigate sediment suspension by breaking waves, a numerical model based on large-eddy-simulation (LES) is developed. This numerical model can be used to simulate wave breaking and sediment suspension. The model consists of a free-surface model using the surface marker method combined with a two-dimensional model that solves the flow equations. The turbulence and the turbulent diffusion are described by a large-eddy-simulation (LES) method where the large turbulence features are simulated by solving the flow equations, and a subgrid model represents the small-scale turbulence that is not resolved by the flow model , A dynamic eddy viscosity subgrid scale stress model has been used for the present simulation. By applying this model to Stokes' wave breaking problem in the surf zone, we find that the model results agree very well with experimental data. By use of this model to simulation of the breaking process of a periodic wave, it can be found that the model can reproduce the complicated flow phenomena, especially the plunging breaker. It reflects the dynamic structures of roller or vortex in the plunging breaker, and when the wave breaks, many strong vortex structures will be produced in the inner surf zone where the concentration of suspended sediment can thereby become relatively high.

关键词： wave breaking large eddy simualion subgrid-scale model surf zone marker and cell method sediment suspensian

Nitrous oxide emission by denitrifying phosphorus removal culture using polyhydroxyalkanoates as carbon source

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Journal of Environmental Sciences 2012年第9期24卷 1616-1623页

作者： Yan Zhou Melvin Lim Soekendro Harjono Wun Jern ng Advanced Environmental Biotechnology Center (AEBC-NEWRI) 60 Nanyang Avenue North Wing Level B2 Room O1 Nanyang Technological University 639798 Singapore Keppel Environmental Technology Centre Pte Ltd. 61 Old Toh Tuck Road 597656 Singapore Division of Environmental and Water Resources Engineering School of Civil and Environmental Engineering Nanyang Technological University 639798 Singapore

Nitrous oxide （N2O） emission has been reported to be enhanced during denitrification when internally-stored compounds are used as carbon sources. However, negligible N2O emissions have been detected in the few studies where polyhydroxyalkanoates （PHA） were specifically used. This study investigated and compared the potential enhancement of N2O production, based on utilization of an internally-stored polymer and external carbon （acetate） by a denitrifying phosphorus removal culture. Results indicated that at relatively low chemical oxygen demand-to-nitrogen （COD/N） ratios, more nitrite was reduced to N2O in the presence of an external carbon source as compared to an internal carbon source （PHA）. At relatively higher COD/N ratios, similar N2O reduction rates were obtained in all cases regardless of the type of carbon source available. N2O reduction rates were, however, generally higher in the presence of an internal carbon source. Results from the study imply that when the presence of an external carbon source is not sufficient to support denitrification, it is likely competitively utilized by different metabolic pathways of denitrifying polyphosphate accumulating organisms （DPAOs） and other ordinary denitfifiers. This study also reveals that the consumption of PHA is potentially the rate-limiting step for N2O reduction during denitrification.

关键词： N2O denitrification carbon source enhanced biological phosphorus removal DPAOs PHA

Probabilistic characterization of cyclic shear modulus reduction for normally to moderately over-consolidated clays

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Earthquake Engineering and Engineering Vibration 2016年第3期15卷 495-508页

作者： Iok-Tong ng Ka-Veng Yuen ngai-Kuan Lao Dept.of Civil and Environmental Engineering Faculty of Science and Technology University of Macao

Evaluation of the cyclic shear modulus of soils is a crucial but challenging task for many geotechnical earthquake engineering and soil dynamic issues. Improper determination of this property unnecessarily drives up design and maintenance costs or even leads to the construction of unsafe structures. Due to the complexities involved in the direct measurement, empirical curves for estimating the cyclic shear modulus have been commonly adopted in practice for simplicity and economical considerations. However, a systematic and robust approach for formulating a reliable model and empirical curve for cyclic shear modulus prediction for clayey soils is still lacking. In this study, the Bayesian model class selection approach is utilized to identify the most significant soil parameters affecting the normalized cyclic shear modulus and a reliable predictive model for normally to moderately over-consolidated clays is proposed. Results show that the predictability and reliability of the proposed model out performs the well-known empirical models. Finally, a new design chart is established for practical usage.

关键词： Bayesian analysis cyclic shear modulus empirical model geotechnical earthquake engineering normally tomoderately over-consolidated clays

Non-asymptotic Error Bound for Optimal Prediction of Function-on-Function Regression by RKHS Approach

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Acta Mathematica Sinica,English Series 2022年第4期38卷 777-796页

作者： Hong Zhi TOng Ling Fang HU Michael ng School of Statistics University of International Business and EconomicsBeijing 100029P.R.China Department of Mathematics Hong Kong Baptist UniversityKowloon TongHong KongP.R.China Department of Mathematics The University of Hong KongPokfulamHong KongP.R.China

In this paper,we study and analyze the regularized least squares for function-on-function regression *** our model,both the predictors(input data)and responses(output data)are multivariate functions(with d variables andd variables respectively),and the model coefficient lies in a reproducing kernel Hilbert space(RKHS).We show under mild condition on the reproducing kernel and input data statistics that the convergence rate of excess prediction risk by the regularized least squares is minimax *** examples based on medical image analysis and atmospheric point spread function estimation are considered and tested,and the results demonstrate that the performance of the proposed model is comparable with that of other testing methods.

关键词： Regularized least squares function-on-function regression non-asymptotic error bound reproducing kernel Hilbert space integral operator

A Frisch-Newton Algorithm for Sparse Quantile Regression

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Acta Mathematicae Applicatae Sinica 2005年第2期21卷 225-236页

作者： Roger Koenker Pin ng Department of Economics University of Illinois at Urbana-Champaign IL 61820 USACollege of Business Administration Northern Arizona University 70 McConnell Dr P.O. Box 15066 FlagstaffAZ 86011-5066. USA.

Recent experience has shown that interior-point methods using a log barrierapproach are far superior to classical simplex methods for computing solutions to large parametricquantile regression problems. In many large empirical applications, the design matrix has a verysparse structure. A typical example is the classical fixed-effect model for panel data where theparametric dimension of the model can be quite large, but the number of non-zero elements is quitesmall. Adopting recent developments in sparse linear algebra we introduce a modified version of theFrisch-Newton algorithm for quantile regression described in Portnoy and Koenker[28]. The newalgorithm substantially reduces the storage (memory) requirements and increases computational *** modified algorithm also facilitates the development of nonparametric quantile regressionmethods. The pseudo design matrices employed in nonparametric quantile regression smoothing areinherently sparse in both the fidelity and roughness penalty components. Exploiting the sparsestructure of these problems opens up a whole range of new possibilities for multivariate smoothingon large data sets via ANOVA-type decomposition and partial linear models.

关键词： Quantile regression interior-point algorithm sparse linear algebra