Advanced Signal Processing for Target Enumeration and Localization in Multiple-Input Multiple-Output Radar
Hong Kong Principal Investigator: Dr SO Hing Cheung (The City University of Hong Kong)
Mainland Principal Investigator: Dr HUANG Lei (Harbin Institute of Technology)

Radar is an acronym for radio detection and ranging system. Multiple-input multiple-output (MIMO) radar is an emerging technology which uses a number of spatially separated transmitters and receivers to simultaneously transmit radio waves and to receive the reflected signals for joint processing, respectively, in order to achieve the important tasks of target detection, positioning and imaging. Unlike the conventional phased-array radar which can only transmit scaled versions of a single waveform, the transmit antenna arrays of the MIMO radar are capable of emitting independent and orthogonal signals. The waveform diversity in the MIMO radar paradigm has been shown to offer better identifiability (that is, more targets can be uniquely identified) and higher spatial resolution (that is, more closely-spaced targets can be resolved) over the phased-array counterpart, which leads to significant improvements in signal detection and parameter estimation performance. Nevertheless, many research challenges need to be tackled to advance MIMO radar from concept to reality. For example, a key difficulty is to achieve optimum detection and estimation performance particularly when the signal-to-noise ratio is low or the number of snapshots is small. Furthermore, processing of the multi-dimensional radar data corresponds to enormous computations and thus algorithm complexity is a main concern.

The aim of this research is to devise advanced signal processing approaches for determining the number of targets and finding their positions in an accurate and computationally efficient manner by exploiting the special structure inherent in the MIMO radar signals. In particular, we will utilize random matrix theory for target detection and base on the subspace approach as well as tensor algebra for localization algorithm development. The performance of the devised methods will also be analyzed and evaluated for various MIMO radar application models.

Theoretical and Experimental Study of Quantum Computing and Quantum Simulation with Electron and Nuclear Spins in Solids
Hong Kong Principal Investigator: Prof. Liu Renbao (The Chinese University of Hong Kong)
Mainland Principal Investigator: Prof. Du Jiangfeng (University of Science and Technology of China)

Quantum computers will mark a new era of information technology. The physical implementation of scalable quantum computers is the central topic of current research of quantum information. Among various candidate systems, spins in solids are most promising due to their stability, integrability, and compatibility with existing nanotechnologies. Quantum simulation of interacting many-body systems has been the first motivation and is still a most challenging task for research of quantum computing.

With synergy of theoretical and experimental efforts, this project targets at physical implementation of few-qubit quantum computing and quantum simulation using electron and nuclear spins in solids. The key issues in solid-state quantum computing and simulation are how to protect quantum coherence and implement high-fidelity quantum gates in complex solid-state environments and how to scale up the system and control design. This project will tackle these important problems by a combination of theoretical and experimental approaches. We will (i) design and demonstrate one- and two-qubit quantum gates of electron and nuclear spins in noisy environments, including non-Abelian geometrical control of spin qubits; (ii) design and demonstrate small quantum algorithms and simulations of quantum phase transitions using a few spin qubits in solids, using pulsed magnetic resonance; and (iii) design of scalable architectures of spin-based solid-state quantum computers.

The specific physical system to be investigated in this project will be mostly carbon-based solid-state materials, especially diamond, where the spins have long coherence time even at room temperature thanks to the weak spin-orbit interaction in the light-element materials. The experimental techniques include pulse electron paramagnetic resonance, solid-state nuclear magnetic resonance, and optically detected magnetic resonance of single spins, all of which have been readily grasped by the experimental team. The theoretical methods include many-body theories of spin dynamics in nano-systems, quantum information approaches to quantum phase transitions, exact solutions of few-spin systems, dynamical decoupling theories of coherence protection, and geometrical control of spin systems. All such theories have been developed with significant contributions from the theoretical team.

In the long term, this project will pave the way for scalable quantum computing in solid-state spin systems. Furthermore, the research in this project may also rejuvenate high-precision magnetic resonance spectroscopy, an information acquisition tool widely used in physics, chemistry, materials science, biology and medicine.

Towards Trustworthy Cloud Computing with Component-based Design, Online Evaluation, and Runtime Optimization Techniques
Hong Kong Principal Investigator: Prof. Lyu Michael R (The Chinese University of Hong Kong)
Mainland Principal Investigator: Prof. Wang Huaimin (National University of Defense Technology)

Cloud computing is Internet-based computing, whereby shared resources, software and information are provided to computers and other devices on-demand, like a public utility. With powerful technical and commercial support by leading industrial companies (e.g., Amazon, Google, Microsoft, IBM, etc.), cloud computing is quickly becoming popular in recent years. Cloud applications are often large-scale systems, composed of a number of heterogeneous and distributed cloud components. Providing trustworthy computing is becoming centric to such an emerging computing paradigm, incurring various important and urgent research problems. In particular, it is critical for cloud computing platforms to provide users with reliable and secure Internet-based computing facilities, so that users are willing to put their data and services on the clouds. This project will tackle the major challenges of building trustworthy cloud applications.

A series of research tasks will be conducted in this project. First we attempt to achieve cloud fault prevention in system design and deployment phases via vulnerable cloud component identification and cloud node quality prediction. Upon releasing of cloud applications, we detect robustness, Quality-of-Service (QoS), and functional problems of cloud applications via online evaluation techniques tailored for cloud computing. After identifying the robustness, QoS, and functional problems of cloud applications, we focus on system runtime optimizations by system reconfiguration, reputation mechanisms, and new access controls. A systematic trustworthy cloud computing environment is consequently established. Finally, we conduct experimental verification, implementation, and release of our research outputs and tools to the community.

This project will enable us to build secure and reliable cloud applications efficiently and effectively in the dynamic cloud execution environment. Practical and systematic trustworthy cloud computing techniques will not only promote the development of cloud computing research, but also enable the establishment of industrial practice in applying these techniques to various service-oriented business and finance sectors. By joining force with our mainland China partner, the project can help to maintain Hong Kong's preeminent status as one of the world's major service centers. As a tangible outcome, the proposed techniques of this project will be encapsulated into a toolkit, which will be widely released to industry and academia.

Theory and practice of large-scale 3D urban reconstruction and modeling
Hong Kong Principal Investigator: Prof. Long Quan (HKUST)
Mainland Principal Investigator: Prof. Baoquan Chen (Shenzhen Institutes of Advanced Technology, CAS)

The objective of the project is to investigate a hybrid methodology for the three-dimensional modeling of urban scenes using both two-dimensional color images captured by cameras or videos, and three-dimensional point clouds captured by laser scanners. Both active and passive sensors are jointly mounted on a moving platform, and the captured image data and point clouds are consistently registered with the help of GPS and/or INS. The approach first segments, recognizes, and decomposes the large-scale input into small-scale object-level representations of a specific category. After that, each category of objects is submitted to a modeling method of the category by integrating the strong prior knowledge of the underlying category information. One unifying theme of this family of object modeling methods is that each category of objects is described by its own generative models, which is the key to the efficiency and the robustness of the modeling methods. Finally, the approach will produce both detailed geometry and an appearance representation of the cities which are suitable for viewing both on the ground level as 'road view' or 'street view' and from the air as ¡¥bird¡¦s eye view¡¦ his project is built on our recent achievements in 3D modeling of urban scenes. The two collaborating research teams of the HKUST and the SIAT have been the most active groups n recent years in 3D city modeling. The HKUST group has focused on the image-based approach to leverage its expertise in computer vision, while the SIAT has focused on canner-based approach to leverage its geometry processing expertise in computer graphics.

The Minimized Energy Consumptions and Maximized Resource Utilizations in Large-scale Datacenters
Hong Kong Principal Investigator: Dr. Bo Li (HKUST)
Mainland Principal Investigator: Dr. Zhiyong Liu (Inst. of Computing Technology, CAS)

Datacenters within the ¡§cloud¡¨ of the Internet are providing support for a large variety of applications ranging from e-commerce, scientific computing, virtual
desktop, to online hosting and social network applications. Such platforms consume a significant amount of energy, due to their massive scale and redundancy in order to meet reliability and performance guarantees. This is further aggravated by the fact that the resource utilization in operational datacenters appears to be remarkably low, and in some cases a mere 10%. Apparently, such under-utilized resources in the dimensions of CPU cycles, network bandwidth, disk storage and memory can lead to a substantial waste of capital investment.

Despite the wide deployment of operational datacenters, there is a lack of systematic study on characterizing the dynamic time-varying workload, the fundamental requirement and constraints towards energy and resource optimization. In addition, there are few practical algorithms that incorporate recent advances in virtualization technology and dynamic task migration towards unified optimization of energy efficiency and resource utilization. While existing research has largely focused on optimizing isolated components, in this project, we propose to design a multi-objective optimization framework that aims to maximize resourceutilization and minimize energy consumption. Specifically, we will (1) carry out an extensive measurement study to capture the time-varying workload characteristics of different applications; (2) establish a theoretical framework demonstrating the critical factors that influence the optimization of energy and resource utilization and the fundamental performance trade-offs; and (3) design practical task scheduling and dynamic migration algorithms that can achieve energy efficiency and optimal resource utilization simultaneously. This not only can establish a solid theoretical foundation toward joint optimization of energy and resource usages, but also offer practical guidelines for the design of energy-efficient algorithms towards better resource utilization.

In light of rapid development and deployment of cloud computing services and datacenters in Hong Kong and China, we believe this timely research not only bears tremendous academic significance, but also holds great potential in practical system implementations.

Photochemical properties of endogenous biological molecules: fundamental and application
Hong Kong Principal Investigator: Prof. Jiana Qu (HKUST)
Mainland Principal Investigator: Prof. Yi Luo (Hefei National Lab. for Physical Science at the Microscale)

This proposed project is a multidisciplinary research of high relevance to optical physics, chemistry, life science and engineering. It is encouraged by a recent
successful collaboration between the Hong Kong and mainland PIs' research groups which led to a major discovery of two-photon excitation fluorescence (TPEF) of hemoglobin, an essential protein responsible for oxygen transport in blood1. Subsequently, the two PIs' groups have worked together to develop TPEF microscopy for in vivo label-free imaging of microvasculature in tissue based on the high-energy fluorescence of hemoglobin. We have successfully demonstrated that two-photon excited hemoglobin fluorescence provides a contrast mechanism for label-free imaging of microvasculature in vivo at the tissue level2. This conceptually new discovery of hemoglobin fluorescence is expected to significantly impact the medical diagnosis of blood diseases and disorders, and the development of new fluorescence probes for biological imaging. The success was a result of having a good understanding of the photochemical properties of hemoglobin, the optimal instrumentation for the efficient excitation and collection of hemoglobin fluorescence signals from biological samples. In the proposed research, we will first conduct a series of theoretical and experimental studies to fully understand the unique TPEF characteristics of hemoglobin. Furthermore, we will develop the design strategy and synthesize a new class of fluorescent probes for biological imaging based on the knowledge obtained in the study of photochemical properties of hemoglobin. The new probe will have a similar molecular structure to hemoglobin, but will be optimized for commonly used commercial excitation sources and detection systems. More importantly, the new probes, like the endogenous and non-toxic hemoglobin itself, should introduce minimal disturbance to the biological system of interest being imaged. The proposed research takes advantages of the Hong Kong team's experiences in the development of advanced optical imaging technology for biomedical applications and the Mainland team's experiences in the theoretical modelling of photochemical properties of biological molecules, as well as the design and synthesis of molecular probes for life science research and medical diagnosis.

From bone marrow cells to Schwann cells - in vitro route to specification and utility in re-myelination therapy
Hong Kong Principal Investigator : Professor D.K.Y. Shum (The University of Hong Kong)
Mainland Principal Investigator : Dr Q. Ao (Tsinghua University)

Our ultimate goal of in vitro derivation of Schwann cells from adult tissues is such that they may be used autologously in nerve guidance channels to assist post-traumatic nerve regeneration in both PNS and CNS. The bone marrow harbours renewable progenitor cells that can be tapped for directed differentiation in vitro. Existing protocols for derivation of Schwann cell-like cells (SCLCs) from bone marrow stromal cells (BMSCs) fall short in stability of the acquired phenotype and the functional capacity to myelinate axons. Our preliminary experiments with rat cells indicated that neuro-ectodermal progenitor cells among the BMSCs can be selectively expanded in neurosphere- forming condition and then induced to differentiate to SCLCs in adherent culture. Coculture of the SCLCs with embryonic dorsal root ganglion (DRG) neurons can accomplish fate commitment of the Schwann cells.

In transition to a human protocol for clinical application, a limiting factor is the source of sensory neurons that provide cues necessary for Schwann cell fate commitment. Under Objective 1, this will be addressed by deriving human sensory neurons from induced pluripotent stem cells (iPSCs) and to use these as alternative to DRG neurons to signal the switch to fate commitment. Under Objective 2, we expect to design a new conduit based on uniaxially aligned chitosan nanofibres and heparan sulfate-supplemented medium to support the derived Schwann cells in a nerve bridge that improves axonal regrowth and remyelination. Under Objective 3, we expect to identify key neuronal membrane effector(s) that switch SCLCs to committed Schwann cells and look forward to engineering a neuronal surrogate for the protocol.

This project builds on the collaborative effort of the Hong Kong PI (Shum) and CoI (Chan) together with the Mainland PI (Ao). Collaboration was initiated when Ao took leave from Tsinghua University (Beijing) to be a recipient of a Dr. Cheng Yu-Tung Fellowship (2007-08) and later an International Brain Research Organization (IBRO) Exchange Fellowship (2009). Shum's group has made the leap from neural tissue-derived Schwann cells to BMSC-derived, fate-committed Schwann cells for remyelination studies. Ao contributed expertise in the production of hollow chitosan-based conduits into which BMSC-derived Schwann cells were seeded in Matrigel matrix. Chan's group further complemented with electrophysiological assessment of functional recovery of nerves bridged with the cell-seeded conduit. These provide us with an edge to pursue Schwann cell derivation from human BMSCs towards clinical application in nerve repair and remyelination therapy.

Investigating the role of FOXM1 in the maintenance of human embryonic stem cell pluripotency and genome stability
Hong Kong Principal Investigator: Kwok-Ming Yao (Department of Biochemistry/The LKS Faculty of Medicine/The University of Hong Kong)
Mainland Principal Investigator: Yongjun Tan (Department of Biomedical Engineering/College of Biology/Hunan University)

Stem cells have the ability to self-renew and differentiate into different fetal and adult cell types, a property referred to as pluripotency. The recent establishment of pluripotent human embryonic stem cell (hESC) lines and the successful reprogramming of differentiated cells into induced pluripotent stem cells (iPSCs) have laid the groundwork for "personalized" cell therapy and regenerative medicine. However, better understanding of the molecular basis of regulation of stem cell pluripotency and genome stability is essential before the full therapeutic potential of stem cells can be exploited.

The Forkhead box (FOX) transcription factor FOXM1, previously known as WIN, HFH-11, and Trident, is ubiquitously expressed in proliferating and regenerating cells. FOXM1 function is required for proper cell proliferation and FOXM1-depleted cells had difficulty executing mitosis, and exhibited chromosomal instability and polyploidy. However, its functional requirement in stem cells remains unclear since most studies were conducted using immortalized and cancer cell lines. Interestingly, Prof. Yongjun Tan (PI of the Mainland team) and his colleagues demonstrated recently that FoxM1 is required for the maintenance of pluripotency of mouse P19 embryonal carcinoma (EC) cells. FoxM1 directly regulates the pluripotency-related transcription factor Oct4 and overexpression of FoxM1 alone is enough to upregulate the pluripotent genes Oct4, Nanog and Sox2. Moreover, Prof. Tan has previously shown that FoxM1 is stabilized upon DNA damage, and its increased expression leads to stimulation of the expression of DNA repair genes, suggesting that FoxM1 is an effector of the DNA damage response to maintain genome stability. Independently, the laboratory of Dr. Yao (PI of the Hong Kong team) recently demonstrated that elevated FoxM1 levels protect mouse embryonic fibroblasts against oxidative stress-induced premature senescence.

Based on these recent findings, we hypothesize that FOXM1 is a master regulator that coordinate expression of various pluripotent and DNA repair genes to maintain proper human stem cell function. To address this hypothesis, we plan to investigate the role of FOXM1 in the maintenance of pluripotency and genome stability in hESCs. First, FOXM1-specific short hairpin RNAs will be expressed in the hESC line H9 using lentivirus-based vector to study the effect on the expression of pluripotent genes. The effect of FOXM1 overexpression in counteracting retinoid acid-induced H9 differentiation will also be explored. Moreover, FOXM1 will be tested for its ability to increase the efficiency of the Yamanaka factors in reprogramming mouse embryonic fibroblasts into iPSCs. Second, FOXM1 will be assessed for its requirement to protect H9 cells from oxidative stress-induced DNA damage by examining DNA breaks by immunostaining for γH2AX, 53BP1, and TUNEL foci. Third, to identify the FOXM1-centered protein-protein interaction network in H9 cells, protein complexes containing tagged FOXM1 will be affinity purified and analyzed by mass spectrometry using the in vivo metabolic biotin tagging method. Taken together, these analyses will shed new light into the regulation of hESC pluripotency and genome stability by FOXM1, which is a prerequisite to designing future strategies to optimize the performance of stem cells for cell therapy.

Functional Analysis of Isorhynchophylline in Promoting Autophagy and Protecting Neurons
Hong Kong Principal Investigator: Dr. Li Min (School of Chinese Medicine, Hong Kong Baptist University)
Mainland Principal Investigator: Prof. Ma Long (State Key Lab. of Medical Genetics of China, Central South University)

Neurodegenerative diseases including Parkinson's disease (PD) and Alzheimer's disease (AD) are characterized by accumulation of abnormal protein aggregates in the affected regions of brain. Macroautophagy (autophagy) is a highly conserved process for cellular degradation of cytosolic contents including protein aggregates. Recent studies, using autophagy-defect transgenic mice, revealed a critical role of autophagy in the homeostasis of neurons. Targeting the autophagic pathway in the neuronal cells for the degradation of pathogenic protein aggregates has emerged as a novel and straightforward therapeutic strategy for neurodegenerative diseases. In our preliminary study we identified an autophagy inducer Isorhynchophylline (IRY) from a pool of Chinese medicinal compounds. We found that IRY can induce autophagy in neuronal cell lines (N2a, SH-SY5Y and PC12), primary neuron culture and Drosophila, and it can promote degradation of WT and mutant alpha-synuclein monomers, alpha-synuclein oligomers and alpha-synuclein /synphilin-1 aggresomes in neuronal cells. Given the protective role of autophagy in the neurodegenerative disease, our findings suggest that IRY may be an effective therapeutic agent for the treatment of neurodegenerative diseases including PD.

For a further understanding of the pharmacological action and molecular mechanism of IRY-induced autophagy, this study is aimed to achieve the following objectives:
1. To understand the effects of IRY on autophagy and neuroprotection using animal models based on phenotypic analysis;
2. To examine the role of Beclin-1 complex in the IRY-induced autophagy;
3. To identify the molecular targets of IRY and novel genes mediating the effects of IRY.

To accomplish our objectives, we will test the pro-autophagic and neuroprotective effect of IRY through multiple in vivo transgenic PD models (Drosophila, C. elegans, Mice), examine the role of Beclin-1 in the activation of autophagy by IRY, identify the molecular target(s) of IRY by chemical-proteomics study and screen for genes mediating the effects of IRY in C. elegans.
These results will help us understand the underlying mechanism by which IRY induces autophagy in neuronal cell and provide the basis for the development of IRY into a therapeutic agent for treating neurodegenerative diseases.

Blocking HIV infection by gene encoding neutralizing antibodies
Hong Kong Principal Investigator: Zhiwei Chen, AIDS Institute and Department of Microbiology, LKS Faculty of medicine, University of Hong Kong
Mainland Principal Investigator: Paul Zhou, Institut Pasteur of Shanghai/Chinese Academy of Sciences

With over 27-years of effort, there is still no effective vaccine or therapeutic cure for AIDS. To find a solution, innovative approaches should be comprehensively investigated. Toward this end, since it is extremely difficult to make a vaccine that can induce neutralizing antibodies (nAbs), which can block viral infection and spread, we aim to engineer nAb genes that can then be produced in two different forms. The first form is called GPI-anchored nAbs, which will be presented on the cell surface and display potent anti-HIV activity to prevent viral entry into CD4+ T cells based on our preliminary studies. Since a recent case study has demonstrated the proof-of-concept that it is possible to use HIV co-receptor CCR5-defective cells to cure an infected individual, this form may lead to a cure by generating cells resistant to HIV by transducing target cells with GPI-anchored nAbs. The second form is secretory nAb. This form mimics natural nAbs and allows us to optimize the gene for high levels of nAb expression, which is essential for protection. Since it has been demonstrated in monkeys that the potent 2G12 nAb provides full-protection against viral mucosal infection even at low concentrations, the combined use of potent secretory nAbs may provide better protection to prevent HIV sexual transmission with improved potency while minimizing the emergence of nAb-resistant viruses. We, therefore, hypothesize that the combination of gene-encoding GPI-anchored and secretory nAbs would have broader and synergic effects in blocking diverse HIV (or SHIV) infection and transmission while minimizing the emergence of resistant mutant viruses. To test this hypothesis, we propose two specific aims: (1) To test the synergistic effect of GPI-anchored and secretory nAbs against large panels of multiclade HIV-1 pseudotypes and primary isolates in transduced TZM.bl cells; (2) To test the synergistic effect of GPI-anchored scFvs and secretory nAbs against a large panel of multi-clade HIV-1 primary isolates and SHIV in transduced human T cell line or primary CD4 T and B cells. By testing these two forms of gene-encoding nAbs against a large panel of HIV-1 strains especially isolated from local patients, we seek to develop effective strategies for future HIV treatment and prevention in China as the first step and in the world as the ultimate goal.

Induction of tolerance by alloantigen-specific regulatory T cells in humanized mice and non-human primates
Hong Kong Principal Investigator : TU Wenwei (The University of Hong Kong)
Mainland Principal Investigator : CHEN Gang (Huazhong University of Science and Technology)

Solid organ and bone marrow transplantations are now widely accepted as an effective treatment for end-stage failure of several organs, and malignant and nonmalignant hematologic diseases respectively. Although the treatment with immunosuppressive drugs has undoubtedly greatly improved graft survival, chronic rejection still has considerable impact on long term outcome. Moreover, most of these drugs nonspecifically target the immune response, leading to unwanted side effects. The ideal in transplantation is, therefore, the induction of a sustained state of specific tolerance to alloantigen with minimal or no conventional immunosuppression. Antigen-specific regulatory T cells (Treg) play an important role in maintaining immune tolerance by suppressing pathologic immune responses. Adoptive transfer of antigen-specific Treg can prevent alloantigen-mediated T-cell responses such as graft-vs-host disease (GVHD) and allograft rejection but does not compromise host general immunity in rodents, indicating that antigen-specific Treg-based therapy has substantial promise for these diseases in humans. Recently we have developed a simple and cost-effective novel method to rapidly induce and expand large numbers of functional human alloantigen-specific CD4 Treg from antigenically-naive precursors in vitro using allogeneic CD40-activated B cells as stimulators. In this proposal, we plan to investigate the therapeutic effects of alloantigen-specific CD4 Treg induced by CD40-activated B cells in humanized mouse GVHD model and non-human primate kidney transplantation, and define the underlying mechanisms. This study will provide better understanding of the role of human Treg in the immune tolerance in vivo and develop a more reliable and cost-effective protocol to prevent GVHD and allograft rejection, and accelerate Treg-based therapy in human.

Health Risk Assessment of Toxic Trace Elements and Polycyclic Aromatic Hydrocarbons (PAHs) via Indoor Dust from Coal-burning Households in Rural China
Hong Kong Principal Investigator : Wong Ming-hung (Croucher Institute for Environmental Sciences, and Biology Department, Hong Kong Baptist University)
Mainland Principal Investigator : Liu Wenxin (College of Urban and Environmental Sciences, Peking University)

As a "Coal Kingdom", the use of coal for household cooking and heating is common throughout China, especially in rural areas. Due to epigenetic mineralization, coal contains toxic trace elements such as Ni, Cr, As, F, Pb and Hg, which could not be destroyed during combustion, but are released into air in their original or oxidized form. In addition, the incomplete combustion of domestic coal could result in considerable polycyclic aromatic hydrocarbons (PAHs) released into indoor air. The combustion of coal therefore is the main source of indoor air pollution and has had profound adverse effects on the health of millions of people in China. Chemical pollutants could be adsorbed onto particulate matter (PM) suspended in indoor air that later settles out as indoor dust. However, there are few studies which focus on investigating the spatial and temporal patterns of toxic trace elements and PAHs in indoor air, indoor dust and PM from coal-burning households in rural China and the
toxicity associated with indoor dust and PM.

The present research will be carried out in five purposely selected areas according to the types of domestic energy used in these households: Xuanwei Country, Yunnan Province -Lung cancer epidemic area due to indoor smoky (bituminous) coal combustion; Guiding County, Guizhou Province and Ankang County, Shaanxi Province - Rural households using coal as their primary source of domestic energy; Beijing and Hong Kong - Urban households primarily using liquefied petroleum gas, natural gas or electricity for cooking and heating (as control). An intensive survey consisting of questionnaires will be used to investigate the status of indoor air quality in coal-burning households in rural China and to quantify the concentrations of toxic trace elements and PAHs, Nitro-PAHs and OH-PAHs in indoor air, PM and indoor dusts. This will be followed by an investigation to study the toxic effects of indoor dust and PM on human airway cell lines (human macrophage and bronchial epithelial cells) (inhalation exposure), hepatoma cell lines (ingestion exposure) and keratinocyte cell lines (dermal contact) and to understand the mutagenicity of PM and indoor dust from coal-burning households in rural China. The results generated from the present project will uncover the different exposure pathways to toxic trace elements andPAHs in indoor air from coal-burning households in rural China. The results will also serve as important references for other parts of the world suffering from similar problems.

Investigation of Heat and Mass Transfer Mechanisms in a Novel Total Heat Exchanger
Hong Kong Principal Investigator: Prof. NIU Jian-lei (Department of Building Services Engineering, The Hong Kong Polytechnic University)
Mainland Principal Investigator: Prof. ZHANG Li-zhi (Key Laboratory of Enhanced Heat Transfer and Energy Conservation, South China University of Technology)

The project is to investigate a novel Total Heat Exchanger (THE) for heat and moisture recovery from ventilation air for energy saving in buildings. Total heat recovery is a key technology for building energy efficiency and CO2 emission reduction, especially in hot and humid regions where cooling and dehumidifying fresh air accounts for 20-40% of the energy use for air-conditioning. The novel THE uses one-step fabricated asymmetric vapor permeable membranes (made from Cellulose Acetate) which have very high vapour permeation rates, and a cross-corrugated triangular duct structure which has high convective heat and mass transfer coefficients. The research work will be conducted in the following steps. (1) The heat and moisture transfer model in the asymmetric membranes will be set up using the fractal theory. (2) The airflow, convective heat and mass transfer characteristics in the cross-corrugated triangular ducts under transitional flow regime will be investigated experimentally with Fourier Transformation analysis and numerically with Large Eddy Simulation techniques. (3) The overall heat and mass transfer model of the novel THE, coupling the membrane and duct airflow models, will be established. (4) Using the model developed, patent designs to intensify the overall heat and moisture transfer in the THE will be investigated, with the goal to achieve a sensible effectiveness of 0.8 and a latent effectiveness of 0.7. It is expected that application of the novel total heat exchangers in air conditioning systems in Pearl-River Delta region alone will bring about 10.5 billion kWh electricity save per year.

Biological Methanogenesis of Alkanes: Thermodynamics and Microbial Ecology
Hong Kong Principal Investigator : Ji-Dong Gu (The University of Hong Kong)
Mainland Principal Investigator : Bo-Zhong Mu (East China University of Science and Technology)

Energy shortage is a serious issue facing all countries worldwide, but the situation is devastated by nonrenewable nature of petroleum supply. The reality is that when a petroleum oilfield is closed down after drilling and pumping with current available technologies, there are still about 30-50% of the total crude oil remaining as residues due to tight binding to subsurface matrices and high cost associated with extraction. Subsurface environment is anaerobic due to the lack of molecular oxygen (O2), anaerobic bioconversion of petroleum hydrocarbons, e.g., alkanes and aromatics, by indigenous microorganisms can produce methane, the natural gas. However, only a very limited number of investigations including ours have been reported on microbial population capable of transforming alkanes from oil reservoirs using molecular analysis, but methanogenesis by microorganisms in oil reservoirs has not been fully established in terms of reaction rates. Methane production from hydrocarbons involve consortium of several groups of physiologically and biochemically distinguished microorganisms to participate in different parts of the biochemical conversion steps from substrate compounds to organic acids and then methane, by namely fermentative bacteria, proton-reducing acetogens and methane-producing archaea. Only by a close association among them will they carry out the methane production from hydrocarbon successfully provided the anaerobic condition is maintained. However, both microbial composition and the rate of biochemical reactions are very poorly understood at the moment for oil reservoir systems. In a consortium capable of producing methane, the balance of different microbial groups is regulated and optimized through the intermediate chemical produced, particularly H2, its concentration allows the thermodynamics balance between fermentative process that produces H2 and the H2 consuming ones for methanogenesis. Because of the fundamental physical and chemical characteristics of the methane-producing process, understanding the thermodynamics of H2 on methanogenesis of alkanes is the key basis before manipulation of consortium composition and enhanced conversion of petroleum hydrocarbons to methane can be achieved. With this in mind, we would like to use the methanogenic enrichment cultures established in our joint laboratories to further our in-depth investigations on the microbial composition in these cultures at different temperatures, the microbial biochemical mechanisms involved and the optimization of microbial composition for accelerated methane generation. One key question of this research is on why methanogenesis can take place from alkanes to methane, which will allow better assessment of the biochemical reaction and control such process for the enhanced reaction. At the same time, the initial activation biochemical step will be substantiated in this research project.

Investigating New Methodologies in Transportation Service Procurement between Shippers and Carriers
Hong Kong Principal Investigator: Prof Lim Leong-chye Andrew (City University of Hong Kong)
Mainland Principal Investigator: Prof Wang Fan (Sun Yat-sen University)

Leveraging the extensive experience and connections that the PI has with the large shippers and carries, the project aims to study various interesting operational aspects on transportation service procurement. These operational aspects include the quotation process, the negotiation process, and the optimization process. The outcome of this project will be enhance shipper-carrier collaboration and change the way procurement is done for logistics in years to come.

Development of Smart and Uniform-sized Colloidosomes for Drug Delivery
Hong Kong Principal Investigator : Prof. Ngai To (The Chinese University of Hong Kong)
Mainland Principal Investigator : Prof. Ma Guang-hui (Institute of Process Engineering, Chinese Academy of Science)

Colloidosomes are microcapsules that consist of a hollow core coated by a shell composed of self-assembled colloidal particles. In recent years, colloidosomes have received considerable attention because of their great potential as vehicles for the controlled delivery of active ingredients in medicine, home and personal care products, agrochemicals, and cosmetics.

However, even though examples of the practical usefulness of colloidosomes have been shown, their use as delivery systems has hitherto been extremely limited. This is because of the following three reasons: firstly, most previously described systems rely on the self-assembly of particles in the oil-water interface of a simple emulsion and they subsequently transfer to a different bulk phase to generate the colloidosomes, but the transfer step usually leads to microcapsule damage and a consequent low yield; secondly, the known colloidosomes are highly permeable and most of the cargo would already be lost before its target is reached; thirdly, the size distribution of colloidosomes produced is very broad, which does not make them commercially attractive for the encapsulation of active pharmaceutical and health ingredients where the delivery of an exact amount is crucial.

This proposal thus seeks a new method to create smart colloidosomes by templating from uniform-sized double emulsions. Monodisperse water-in-oil-in-water (W/O/W) double emulsions stabilized by pH-responsive nanoparticles will be prepared by using a membrane emulsification technique. The irreversibly adsorbed nanoparticles at the two oil/water interfaces can effectively inhibit the coalescence between the inner and outer water, and also protect an encapsulated cargo upon removal of middle oil phase, that is well in excess of what can be achieved by double emulsions stabilized by surfactants or polymers. More importantly, these two nanoparticle-covered interfaces will combine and lead to responsive colloidosome walls containing dual layers of nanoparticles, which will be very robust and in response to a pH triggering stimulus. The size of the double emulsions and consequently the dimensions of the resulting colloidosomes will be precisely controlled by the pore size of the membrane. The permeability, mechanical strength, and stimulus-triggered release of the colloidosomes will be adjusted and the potential applications of produced colloidosomes as bio-drug (e.g., insulin) carriers for oral administration will be exploited both in vitro and in vivo.

The successful accomplishment of this project will not only provide a general and robust strategy for microencapsulation, but will also result in the development of a novel orally administered drug carrier.

Air-surface Exchange of Persistent Organic Pollutants (POPs) and Heavy Metals (HMs) in Peri-urban Agricultural Ecosystems of the Pearl River Delta, South China
Hong Kong Principal Investigator: Prof. LI Xiangdong (PolyU)
Mainland Principal Investigator: Dr ZHANG Gan (Guangzhou Institute of Geochemistry, Chinese Academy of Sciences)

Persistent organic pollutants (POPs) are chemicals toxic to humans and wildlife. They are able to stay in the environment from months to decades, and can be distributed among different environmental media. The Stockholm Convention targeting source reduction and restriction of a number of POPs has been adopted by most countries and regions in the world. These chemicals include organochlorine pesticides (OCPs), such as DDTs and HCHs, and some emerging POPs, such as polybrominated biphenyl ethers (PBDEs) which are a group of brominated flame retardants (BFRs).

The accumulation of POPs and heavy metals (HMs) in agricultural soils can lead to deterioration in soil quality; this, in turn, could post a threat to food safety and human health. A peri-urban agricultural ecosystem is susceptible to the receipt of large amounts of toxic chemicals from intensive human activities in nearby cities. However, little is known of the accumulation rates and fate of typical POPs in peri-urban agricultural eco-systems, where intensive industrialization and urbanization are taking place. This is particularly the case with regard to rice paddy fields, which occupy a vast land area in Asian developing countries. Such sites are becoming global industrial bases as well as the target destination of more than 90% of the world's e-waste.

The Pearl River Delta (PRD) region, including Hong Kong and Macau, is in fact a city cluster area with highly developed industrial operations. These industrial operations and urban activities have led to the release of large quantities of pollutants into the environment, including BFRs. The region has traditionally been, and still remains, a very important agricultural region in China. Past agricultural practices have left high levels of residue of legacy organochlorine pesticides (OCPs), such as DDTs and HCHs in soils. Considering the different input histories of 'old' OCPs and 'new' BFRs, obtaining the understanding of current air-surface exchange fluxes and budgets in the peri-urban paddy fields of this subtropical region is a matter of great importance. In this proposed research project, we aim to study the air deposition exchange fluxes in typical paddy fields using a combination of innovative field sampling programmes and laboratory modelling experiments. This will probably be the first systematic investigation into the geochemical cycling of POPs in one important type of agricultural soil - paddy fields in a subtropical region. The outcome of the project will contribute to a better understanding of the biogeochemical processes and dynamics of POPs in peri-urban paddy ecosystems of a subtropical region, and their potential impact on the global fate of these chemicals. It will also shed light on the important issues of regional soil quality and food safety.

Design and synthesis of advanced functional materials from microfluidic approaches
Hong Kong Principal Investigator: Prof. Weijia Wen (HKUST)
Mainland Principal Investigator: Prof. Jianhua Qin (Dalian Inst. of Chemical Physics, CAS)

This project involves the study of functionalized materials using microfluidic approaches. How to functionalize materials is a very challenging problem due to the complicated design and fabrication process. As we know, the conventional materials can be made via different synthesis methodologies physically or chemically.

However, materials with unique properties such as smart materials are difficult to produce using conventional techniques. Therefore, a novel method needs to be developed for such kind of material production. Specifically, the fabrication of microsphere with different configurations and complicated structures, like
multilayered structures, can be easily generated through microfluidic approaches. The design and fabrication of artificially functionalized materials through microfluidic approaches has become a very hot research topic recently not only within the microfluidics community but also among researchers in various fields like materials, physics, chemistry as well as biology.

Based on our previous experiences in microsphere and nanoparticle design and fabrication, in this project, we will design and fabricate different types of microspheres with functionalized properties, in the meantime, the fabrication of nano-materials from microfluidic approaches will also be carried out in parallel. The characterization and applications of functional materials will be performed. We believe that the deliverables from this proposal will be a new knowledge on and a new fabrication methodology for artificial materials. It is predicted that these newly functionalized materials may eventually be utilized in some realistic applications influencing our future living, especially in biological, energy as well as other aspects. The long-term significance of this project is clear: the realization of a new class of smart/intelligent materials with endless applications.

New fluorescent sensors with aggregation-induced emission characteristics
Hong Kong Principal Investigator: Prof. Benzhong Tang (HKUST)
Mainland Principal Investigator: Prof. Zhen Li (Wuhan University)

Scientists and technologists have devoted much effort to the development of sensitive and selective sensory systems for the detection of chemicals, metals, and
biopolymers because they play important roles in industrial, environmental and biological processes and systems. Sensors based on fluorescent materials have
attracted special attention, as they offer high sensitivity, low background signals, and wide dynamic ranges. However, it is well-known that aggregation of conventional luminophores often quenches light emission, which limits the application scope of the luminophores. This problem must be solved because fluorescent materials are commonly used as solid substances in commercial devices. Various chemical, physical and engineering approaches have been taken to interfere with the fluorophore aggregation, but the attempts have so far met with only limited success. It would be perfect, if a system can be developed, in which fluorescence is boosted, instead of being quenched, by aggregate formation.

In 2001, we discovered an unusual phenomenon of aggregation-induced emission (AIE): a series of propeller-shaped molecules named siloles show faint or
no fluorescence in the solution state but emit efficiently in the aggregate state. The AIE effect boosts the emission efficiency of the siloles by more than two orders of magnitude, turning them into strong light emitters. Since then, AIE fluorogens with high quantum yields and full emission colors have been developed. The AIE fluorogens have been used for the fabrication of efficient optoelectronic devices; in contrast, much less work has been done on exploring their applications in environmental and biological sciences. In this research project, we plan to develop new AIE systems with potential applications in these areas. Our AIE approach is novel and useful because it permits the use of fluorogen solutions with any concentrations and enables the development of turn-on sensors with high sensitivities by taking advantage of the fluorogen aggregation. To achieve the project objective, we will team up with an active research group led by Professor Zhen Li at Wuhan University. New fluorogenic materials with AIE feature will be generated through innovative synthetic routes. Through close collaboration, new synergy will be developed and new avenues will be opened. Research efforts and strengths of our team in the area will be coordinated and cross-fertilized. It is expected that this project will lead to the development of new materials and useful technology, which will help sharpen the competitive edge of our local industry.

Mechanical-Electrical-Chemical Coupling Properties of Nanoporous Metals
Hong Kong Principal Investigator: Prof. Tongyi Zhang (HKUST)
Mainland Principal Investigator: Prof. Lijie Qiao (Univ. of Science & Technology Beijing)

Surfaces of solids play an essential role in surface-chemistry-driven actuation, absorption, catalysis, corrosion and dealloying, stress-charge interactions, and
size-dependent behaviors. In nanomaterials and nanoporous materials, the surface-to-volume ratio is extremely large, which makes the role of surfaces more
significant. Graphene, which is made of a single layer of carbon, is an extreme example, where all atoms are on the surface. However, surfaces of solids behave differently from surfaces of liquids because atoms in solids cannot move quickly so that solids have their own shapes and can sustain deformation, which brings great academic challenge. To satisfy academic curiosity and to bring industrial innovation, it is necessary to understand and predict the mechanical, electrical and chemical coupling behaviors of nanomaterials and nanoporous materials, which may exhibit size-dependent properties when conventional continuum thermodynamic theory is applied. Although great progress has been achieved in the research on the mechanical, electrical and chemical coupling behaviors, there are still some challenging issues, which hamper the further development of thermodynamic theory for nanomaterials and nanoporous materials. Based on our rich research experiences in surface stress and surface elastic constants of solids, atomistic simulations, mechanical-electrical coupling behaviors of bulk materials, electrochemistry, corrosion, dealloying, hydrogen-induced strain and stress, formation of porous metals, stress corrosion cracking, etc, we propose to study the mechanical-electrical-chemical coupling properties of nanoporous metals. The purpose of the proposed research is to develop a nonlinear thermodynamic theory to explain and predict the strain-charge-chemical coupling behaviors of nanoporous metals. To achieve this goal, we shall conduct experiments, theoretical study, and atomistic simulations. The designed nanobridge test on individual samples with
well-defined geometry will generate reliable experimental data about the strain-charge-chemical behaviors of nanometer-sized metals. The theoretical study
will consider nonlinear initial in-plane deformation induced by relaxation of nanometer-thick films. This will lay the foundation of nonlinear thermodynamic
theory for the coupling behaviors of nanoporous metals. The atomistic calculations will simulate the strain-charge-chemical behaviors of nanometer-thick films.
Successful completion of the proposed project will facilitate the development of the thermodynamic theory and nanotechnology, which will have a high impact on both academic research and engineering practice. The anticipated output will become guidelines for the wide application of nanomaterials and nanoporous materials in high-tech industries.

Experimental Investigation of the Local Balance Between Buoyant and Inertial Forces in Turbulent Thermal Convection
Hong Kong Principal Investigator : Prof. Xia Keqing (The Chinese University of Hong Kong)
Mainland Principal Investigator : Prof. Zhou Quan (Shanghai University)

An experimental project is proposed to study the relationship between buoyant forces and inertial forces over various scales in turbulent thermal convection over the Rayleigh number range 10⁹ < Ra < 10¹¹. The project aims to determine and understand the dynamics that drive the turbulent kinetic energy transport from large scales to small scales via simultaneous measurements of velocity and temperature differences over various real-space scales. The spatial distributions of local Bolgiano scale L_B(x) and the local Kolmogorov (dissipative) scale η(x) at various values of Ra will also be investigated.

These objectives will be achieved by the combination of a non-standard high-resolution laser Doppler velocimetry (LDV) and a high-resolution multi-point thermometry technique. With the accessible parameter range of the apparatus we can test whether a balance between buoyant forces and inertial forces exist in the inertial range of scales in convective turbulence. The project will provide a rigorous experimental test on whether the Bolgiano-Obukhov (BO59) scaling, a long-existing model proposed in 1959 for the scaling of the cascades of the velocity and temperature fields in buoyancy-driven turbulence, exists in convective turbulent flows.

We expect the results coming out of this study to shed light on the nature of cascades from large to small scales of the turbulent kinetic energy and temperature variances in buoyancy-driven thermal turbulence, which is an important class of turbulent flows occurring ubiquitously in nature.