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PolyU develops versatile fluidic platform for programmable liquid processing

Society relies heavily on diverse fluidic technologies. The ability toprecisely capture and release various chemical and biological fluids plays a fundamental role in many fields.A long-standing challenge is to design a platform that enables the switchable capture and release of liquids with precise spatial and temporal control and accurate volumes of the fluid. Recently, researchers at The Polytechnic University of Hong Kong (PolyU) have invented a new method to effectively overcome this challenge. Led by Prof. WANG Liqiu, Otto Poon Charitable Foundation Professor in Smart and Sustainable Energy, Chair Professor of Thermal-Fluid and Energy Engineering, of the PolyU Department of Mechanical Engineering, the research team has developed a unique fluidic processor, “Connected Polyhedral Frames” (CPFs). With CPFs, switching between liquid capture and release becomesreversible, programmable and independent of used polyhedral frames and processed liquids, making the processor a meta-metamaterial.This research has recently been published in Nature Chemical Engineering, with Dr ZHANG Yiyuan, Research Assistant Professor of the Department of Mechanical Engineering, as the first author. Unlike in the highly developed area of solids manipulation, convenient handling of fluids remains a cumbersome task despite the ubiquity of fluids in, for example, the healthcare, pharmaceutical, biological and chemical industries. As fluids interact with tools, they frequently wet and spread on the solids, preventing complete liquid transfer, impairing volumetric accuracy and causing inter-sample cross contamination. To preserve the purity of fluids, disposable plastics such as pipettes and microtubes are widely used, adding to the global problem of plastic waste. Reversible switching between capture and release is the key to CPFs’ capability to precisely process liquids, enabling the liquid in the network to be retained or drained locally, dynamically and reversibly as desired. In the CPFs, frames above the single-rod connection without a pathway for liquid drainage between frames, capture and retain liquids, thus functioning as capturers. While the frames above the double-rod connection imbibe but release liquids, serving as releasers. This is because when the CPFs are lifted from the liquid, a liquid film forms between the double-rod connections, creating channels between frames that facilitate liquid release. Reversible switching between capture and release can be achieved, using available tools, by constructing or breaking the liquid continuity between frames. CPFs offer a versatile platform that enables many unique functions including 3D programmable patterning of liquids, 3D spatiotemporal control of concentrations of multiple materials, packaging of 3D liquid arrays and large-scale manipulation of multiple liquids. It is compatible with a broad range of liquids, including but not limited to aqueous solutions, biofluids, hydrogels, organic solvents, polymer solutions and oils. Therefore, a variety of biomaterials and chemicals can be incorporated into CPFs for various applications. To demonstrate the practical utility of CPFs in controlled multidrug release, Prof. Wang’s team designed a CPF network for the 3D binary liquid patterning of vitamins B2 and B12. The two vitamins, representing two different types of drug molecules, were encapsulated in sodium alginate hydrogel and gellan gum, respectively, and released in aqueous solution. By altering the thickness of the gel membrane, the relative release rates of the two “drugs” can be precisely controlled. Traditional cotton swabs and flocking swabs suffer from severe sample residues during their sample release. CPFs can effectively overcome this challenge because their frame structure renders free liquid-liquid interfaces for high release efficiency. Using the influenza virus as an example, the research team demonstrated the superiority of CPFs as sampling tools with much better release performance. When the virus concentration was low, the CPFs detected the virus, while both the flocking swab and cotton swab failed to do so. The team has also demonstrated the application of CPFs in biomaterial encapsulation. Taking Acetobacterium encapsulation as an example, the CPFs show many advantages over traditional devices, including by facilitating the separation of bacteria and reaction products, simplifying the microbial reaction process and enhancing the utilisation rate of bacteria. It is conceivable that CPF could also be applied to encapsulate other biological materials for efficient production of other valuable products. In addition to medical and microbial applications, Prof. Wang’s team has further demonstrated the practicability of CPFsfor air conditioning. They prepared a commercial-scale humidifierprototype, which has a higher water storage capacity and requires less water flow, making them potentially more energy efficient.The CPFs also allow large-scale 3D liquid dispersionto form a larger surface area, making them very useful for gas absorption. An ideal CO2 cycle process is successfully generated with CPFs, which includes carbon capture and storage and CO2 reutilisation. Importantly, each frame in CPFs captures or releases liquids independent of its base materials, structures and handled liquids, being thus an innovative meta-metamaterial that makes the dream of “precisely scooping water with a bamboo basket” come true. The availability of such a fluidic processor sets a new standard for handling liquids with controllability, versatility and high performance, inspires a new field of meta-metamaterials, and facilitates new scientific and technological breakthroughs in various fields.  

PolyU team won first place in High-Efficiency Power Amplifier Student Design Competition

A team of three undergraduate students from the Hong Kong Polytechnic University (PolyU) won the First Place in High-Efficiency Power Amplifier Student Design Competition at the prestigious 2024 IEEE MTT-S International Microwave Symposium held in Washington, D.C., USA. The students were under the guidance of Dr Zhou Xinyu, Research Assistant Professor and Head of the RF Microelectronics Circuit (RFMC) Laboratory in the Department of Electrical and Electronic Engineering of PolyU. The three PolyU team winners are Wang Yanze, Bi Jingyu, and Yuan Ye, all studying the Bachelor of Engineering (Hons) Degree in Internet-of-Things (IoT) with a Secondary major in Artificial Intelligence and Data Analytics (AIDA). With a 20-year history, the competition aims to seek innovative topologies for high-efficiency power amplifiers for the next generation of wireless communications. This year, 42 teams of doctoral students from around the world (including the United States, Germany, Canada, Italy, Ireland, South Korea, and Mexico) participated in the event. The PolyU team won the honour for the first time in this international competition, and it was the only team composed of undergraduate students to stand out successfully. The award not only recognises the students’ effort but also demonstrates PolyU’s research strengths. The RFMC laboratory will continue to focus on research into RF microelectronic circuits based on third-generation semiconductor technology, leveraging the upcoming microelectronics development wave in Hong Kong to continue proposing innovative circuit design methods and concepts.  

PolyU develops ultra-stable, record high brightness perovskite LEDs with promising applications

Perovskite materials are significant for enhancing the development and performance of light-emitting diodes (LEDs). However, there are certain technological limitations in advancing overall device efficiency, brightness and lifetime, with the operational stability of Perovskite LEDs (PeLEDs) remaining a major challenge. Researchers from The Hong Kong Polytechnic University (PolyU) have made a breakthrough by developing a 3DFAPbI3 perovskite material system that enables high brightness, efficiency and long device lifetime simultaneously. Prof. LI Gang, Sir Sze-yuen Chung Endowed Professor in Renewable Energy, Chair Professor of Energy Conversion Technology of the Department of Electrical and Electronic Engineering of PolyU, together with Postdoctoral Fellow Dr Zhiqi LI, Research Assistant Professor Dr Zhiwei REN, and the rest of the research team, have engineered a novel technology using an alkyl-chain-length-dependent ammonium salt molecule modulation strategy. They elucidated the roles of alkylammonium salts in managing crystal orientation, controlling grain size, suppressing non-radiative recombination, and thereby enhancing device performance. This represents a critical leap towards future applications and commercialisation of efficient and ultra-stable PeLEDs with record brightness. The research team have achieved efficient, ultra-bright, and stable PeLEDs simultaneously, with high  Electroluminescence External Quantum Efficiency of 23.2%, a record radiance of 1,593 W sr−1 m−2 and a much improved record lifetime of 227 h (at a high current density of 100 mA cm−2). This demonstrates the best performance for DC-drive near-infrared PeLEDs at high-brightness and stability levels. Their research “Grain orientation management and recombination suppression for ultra-stable PeLEDs with record brightness”, has been recently published in the energy journal Joule. Prof. Li Gang said, “This strategy suggests that PeLEDs are not only high-efficiency devices in the laboratory but also promising candidates for commercial high-brightness lighting and display applications, competing with commercially available quantum-dot-based and organic LEDs.” The research team revealed that the performance of PeLEDs is strongly affected by the balance among oriented crystallisation, grain size control and suppression of non-radiative recombination. The key to resolving this dilemma lies in adjusting the molecular interaction between the long-chain alkylammonium salts and perovskite nuclei. Alkylammoniums promote oriented crystallization of perovskite film for lighting, while the molecular interaction between alkylammonium and perovskite affects PeLEDs performance. Notably, the team has successfully utilised molecular engineering of long-chain alkylammonium salts to modulate crystallisation kinetics. This breakthrough strategy enables the production of high-efficiency and ultra-brightness near-infrared PeLEDs with ultralong stability, even under large current excitation. In the development of LEDs, PeLEDs possess substantial advantages, including pure colour, a wider display colour gamut range, cost effectiveness and solution processiblity offering greater flexibility in production. The team’s discovery contributes significantly to the advancement of PeLEDs and their technological impact. 

HEROCARE: A Fearless Journey in Radiotherapy

As part of their treatment preparation, a young cancer patient attends a simulated radiotherapy session at The Hong Kong Polytechnic University (PolyU) with her favourite cartoon characters. The immersive environment, crafted for the child's well-being and featuring her favourite characters, fosters confidence and diminishes fear with vibrant colours, love, and care. The PolyU “FRIENDS理伴童行” Team at the Department of Health Technology and Informatics, alongside the Industrial Centre, utilises immersive mixed reality technology at the Hybrid Immersive Virtual Environment (HiVE) of PolyU to create a personalised, comforting space for paediatric radiotherapy preparation. Supported by the Lee Hysan Foundation, the HEROCARE programme at PolyU harnesses HiVE technology to enhance positive experiences for both patients and caregivers throughout radiotherapy. As a result, over 88% of participants completed radiotherapy without anaesthesia. 

PolyU and Zhongshan jointly establish technology and innovation research institute to advance development of biomedicine

The Hong Kong Polytechnic University (PolyU) and the Zhongshan Municipal People’s Government (Zhongshan Government) officially signed a cooperation agreement on 30 July to jointly establish the “PolyU-Zhongshan Technology and Innovation Research Institute”. This collaboration marks an important step forward for both parties in promoting the development of biomedicine in the two regions and enhancing industry-academia-research cooperation. Prof. Jin-Guang TENG, PolyU President led a delegation to participate in the 2024 Zhongshan Global Investment Promotion Conference, where the cooperation agreement signing ceremony for the Research Institute was also held. Witnessed by Mr GUO Wenhai, Secretary of the CPC Zhongshan Municipal Committee; Mr XIAO Zhanxin, Deputy Secretary of the Zhongshan Municipal Party Committee and Mayor of Zhongshan City; Prof. Gary WONG, Chair Professor of the Department of Chemistry at PolyU; and Mr Victor ZHAO, Assistant Director of the Research and Innovation Office at PolyU, the agreement was signed by Mr YE Hongguang, Member of the Leading Party Group of the Zhongshan People’s Government and Vice Mayor of Zhongshan City, and Prof. Wing-tak WONG, Deputy President and Provost of PolyU. Prof. Teng stated, “Our collaboration with the Zhongshan Government to establish this Institute aligns in terms of timing, geographical advantage and our strong working relationship. This is not only an important milestone in the development of our university but also a starting point for jointly promoting innovative technology development with Zhongshan. The establishment of the Institute will inject new momentum into the economic and social development of Zhongshan, as well as responding to President XI Jinping’s call to make good use of the Shenzhen-Zhongshan Corridor, promoting the integration of the east and west banks of the Pearl River Estuary, strengthening innovation and technology cooperation in the Guangdong-Hong Kong-Macao Greater Bay Area, and advancing industry-academia-research transfer to empower new quality productive forces in the region.” The Institute will focus on the field of biomedicine, particularly independent research and development of pharmaceutical products, and is committed to improving community healthcare. The Institute will also closely collaborate with hospitals in Zhongshan, promoting the translation of research outcomes through industry-academia-research cooperation to benefit the public. The opening of the Shenzhen-Zhongshan Corridor enhances transportation and the flow of personnel, capital and technology between the two cities, helping Zhongshan better integrate into the overall GBA development. Serving as a hub for innovative technology, the Institute aspires to provide robust technical support for the industrial upgrading and act as a catalyst for the economic development of Zhongshan. This cooperation not only strengthens the connection between PolyU and the Zhongshan Government, but also promotes their joint efforts to seize and embrace the immense opportunities brought about by innovative technology.

PolyU scholar discovers key mechanism of intraocular pressure regulation suggesting novel treatment approaches for glaucoma

Glaucoma is one of the leading causes of visual impairment and blindness. According to statistics from the Hospital Authority, in Hong Kong, three out of every 100 individuals aged over 40 suffer from glaucoma. In its early stages, obvious symptoms may not be present and those less obvious are often overlooked. By the time patients notice changes in their vision, the condition is usually severe. Dr Samantha SHAN, Research Assistant Professor of the School of Optometry of The Hong Kong Polytechnic University (PolyU) and her team have discovered the mechanism of intraocular pressure (IOP) regulation, paving the way for novel treatment approaches for glaucoma, with the aspiration of preventing vision loss from this disease. In glaucoma patients, the fluid within the eye (known as “aqueous humour”) continuously flows, resulting in higher IOP for which long-term medication is required. However, current drugs have limitations in that they can only slow disease progression rather than halt it completely. Drugs may also have suboptimal tolerability and their efficacy diminish over time. The microRNA(miR)-17-92 cluster is known to play an important role in cell signalling, but its specific functions in the eye are not well understood. In this respect, Dr Shan and her team’s research focus lies in gaining insights into the mechanisms of miR-17-92 cluster members and their effects on IOP. The team has identified thrombospondin-1 (TSP-1) as a protein that reduces the outflow of aqueous humour and increases IOP. Concurrently, the team mimicked three members of the miR-17-92 cluster in human trabecular meshwork (hTM) cells which are responsible for draining aqueous humour within the eye. It showed that the expression of TSP-1 was repressed, resulting in an approximately 73% increase in the outflow of aqueous humour in mice. Dr Shan’s team has recently been recognised with a prestigious 2024 Shaffer Research Grant from the Glaucoma Research Foundation to further explore the effects of miR-17-92 members in IOP regulation. Looking forward, the team will investigate the direct interaction between specific miRNAs and TSP-1 by blocking the potential target sites of the three miRNAs in TSP-1 in hTM cells. They will also examine the functional consequences of modulating this pathway on aqueous humour outflow and IOP regulation in vivo. This would be achieved by utilising intravitreal injections of a TSP-1 target-specific blocker or miRNA mimics in mouse eyes. Dr Shan remarked, “Genomic and proteomic approaches play a crucial role in understanding the genetic and molecular mechanisms underlying diseases such as glaucoma. In the context of glaucoma treatment, these approaches can help identify potential biomarkers, therapeutic targets and personalised treatment options, with far-reaching implications. The Grant also demonstrates PolyU’s excellence as hosting one of the top eye research centres in the world. It encourages me and my team to continue to make significant strides in glaucoma research and contribute to the better care of glaucoma patients.” With over a decade of experience in molecular research, in her work, Dr Shan has demonstrated proficiency in utilising genomic and proteomic approaches. Her research interests are mechanism of aqueous humour formation, outflow facility and IOP regulation, microRNAs on outflow facility, DNA methylation of potential candidates on outflow facility and IOP regulation. Dr Shan has also received support from the Hong Kong SAR Government’s Health and Medical Research Fund for two projects as a principal investigator. The projects aim to discover gene editing methods for treating glaucoma and unravel the role of epigenetic regulation in glaucoma respectively. Dr Shan has also served as a co-investigator on other diverse research topics and has secured notable research funding, including the Research Grants Council’s General Research Fund.

PolyU and Nanjing Zhuling signed MoU to establish joint laboratory on industrialised construction

Hong Kong Polytechnic University (PolyU) and Nanjing Zhuiling Technology Co., Ltd. signed a Memorandum of Understanding (MoU) on 25 July to establish a joint laboratory on industrialised construction. The MoU was signed by Prof. Christopher Chao, Vice President (Research and Innovation) of PolyU and Mr AnGang Dai, CEO of Nanjing Zhuling Technology. Dr Zhiheng Zhao, Research Assistant Professor of Department of Industrial and Systems Engineering of PolyU and Dr Liu Hengzhi (Class of 2009), COO and Product Director of Nanjing Zhuling Technology will serve as directors of the joint laboratory. The joint laboratory will focus on research areas, including the digitalisation of construction in the industrial metaverse, digital twins, construction robotics, intelligent building systems, as well as advanced automation and AI-driven solutions. By leveraging the respective strengths in research resources, testing environments and application scenarios, the two parties aim to enhance the safety and efficiency of the construction process, and achieve breakthrough results in the digital transformation of the construction industry. This cooperation is of great significance in promoting innovative development in the construction field, injecting new momentum into the industry, and contributing to the generation of new high-quality productive forces for society.

PolyU scholar confirms maternal positive mental health correlated to children’s brain development

Pregnancy brings about profound changes, and nurturing positive mental health during this period is crucial for the long-term health and well-being of children. Through scientific investigations on young children, Prof. QIU Anqi, Professor of the Department of Health Technology and Informatics and Global Stem Scholar at The Hong Kong Polytechnic University (PolyU), along with her research group, has validated the impact of maternal positive emotions on children’s brain development and function. According to the research conducted by Prof. QIU, girls born to mothers who reported experiencing greater positive mental health during pregnancy showed larger bilateral hippocampi. Increased hippocampal volume is directly related with improvements in memory performance.  Significantly, children of mothers with higher levels of maternal positive mental health demonstrated altered functional connectivity within several neural networks, including the default mode, salience, executive control, amygdala and thalamo-hippocampal networks. These networks link to a wide range of cognitive, emotional, memory-related brain development and functions.  Maternal positive mental health has long-lasting impacts on the brain development of offspring. These impacts are especially pronounced in the brain structures such as the hippocampus and amygdala, as well as functional networks such as the visual, default mode and frontal networks, which are integral to emotion perception and regulation.  Prof. QIU said, “The research findings extend the study of maternal mental health beyond maternal psychopathology, suggesting the importance of promoting positive maternal mental health during pregnancy as a potential protective factor for children’s brain development.” The research provided new evidence that improved maternal positive emotion during pregnancy has the potential to promote the hippocampal development of children. Therefore, maternal positive emotion significantly influences the quality of parenting relationship after delivery, including greater material sensitivity, warmth and responsiveness to the child’s needs, as well as enhanced infant socioeconomical development.  The study used a longitudinal dataset to investigate how positive emotions experienced by mothers during pregnancy affect the brain structure and function of 7.5 years old children. Both structural and functional magnetic resonance imaging (MRI) were used in the study involving 381 Asian participants in Singapore. The research titled “Maternal positive mental health during pregnancy impacts the hippocampus and functional brain networks in children” was published in Nature Mental Health.  A measure of positive maternal mental health, which includes positive affect and emotional well-being during pregnancy, was developed through confirmatory factor analysis of questionnaires administered at 26–28 weeks. The study findings highlight the importance of delving into a broader spectrum of mental health aspects beyond just illness, advocating for positive emotions among mothers.   “Our research further confirmed the importance of positive mental health and well-being during pregnancy, which is also a key determinant in child brain development,” said Prof. QIU.  Her research areas focus on brain development and the use of artificial intelligence to predict and analyse mental health issues in young people.   

PolyU and ADA SPACE signed a cooperation agreement

The Hong Kong Polytechnic University (PolyU) and ADA SPACE Co. Ltd. (ADA SPACE) signed a cooperation framework agreement on 17 July during a signing ceremony on campus. The cooperation framework agreement was signed by Prof Christopher Chao, Vice President (Research and Innovation) of PolyU, and Dr. Wang Lei, CEO of ADA SPACE. The two parties will explore the possibility of establishing of a joint remote sensing satellite technology laboratory. This cooperation marks a solid step forward in the research and development collaboration between the two parties in the fields of satellite and space computing technology, jointly contributing to national development through scientific research. Representatives from PolyU's Faculty of Engineering, Department of Land Surveying and Geo-Informatics, Department of Computing, and the Office of Research and Innovation also attended the signing ceremony. ADA SPACE is a leading AI satellite internet technology company founded by leading talents from satellite internet research institutions and the internet industry. Since its establishment, ADA SPACE has successfully completed 13 space missions and has built a strong foundation in satellite technology and space computing.

PolyU and Institute of Advanced Science Facilities, Shenzhen signed a cooperation agreement

The Hong Kong Polytechnic University (PolyU) and the Institute of Advanced Science Facilities, Shenzhen signed the Strategic Collaborative Framework Agreement on 11 July. This marked a solid step forward for both parties in the fields of technological and disruptive innovation. Prof. Christopher CHAO, Vice President (Research and Innovation) of PolyU, and Prof. HU Shuiming, Deputy General Manager of Engineering Department of the Institute of Advanced Science Facilities of Shenzhen, signed a cooperation agreement on behalf of the respective parties. The ceremony was witnessed by Ms CAI Ying, Guangming District Party Secretary, Ms YANG Li, Head of the United Front Work Department, Mr YAO Gaoke, Deputy District Mayor of Guangming District, Dr Lawrence LI Kwok-chang, Deputy Council Chairman of PolyU, Prof. Jin-Guang TENG, President of PolyU and Prof. Kwok-yin WONG, Vice President (Education) of PolyU. Prof. Jin-Guang TENG stated that by leveraging the facilities of the advanced photon sources in Guangming, it fosters collaborative technological innovation between Shenzhen and Hong Kong, and also facilitates the transformation of scientific and technological achievements and contribute to making PolyU a globally leading research university. This initiative also aims to inject vitality into the construction of high-level scientific facilities at the PolyU-Shenzhen Industrial Technology and Innovation Research Institute (the Research Institute). Prof. HU Shuiming highlighted that as a Comprehensive National Science Center of the Greater Bay Area, the joint partnership of experimental stations will enable ultrafast and ultrafine spatiotemporal resolution research in the fields of information materials, nano/quantum materials, and complex biomolecules. The Research Institute is in the stage of the construction of the free-electron laser facility in Shenzhen, aiming to attract more users to participate in its construction to better serve scientific research and industrial applications at large. The PolyU and the Guangming District of Shenzhen have a solid foundation for cooperation. A framework agreement was signed to jointly establish the Research Institute in August 2023. Successive joint efforts would bring new momentum to technological innovation, integrate their respective strengths and facilities, and foster continuous development of the Greater Bay Area on the global stage. Prof. Jianhua HAO, Director of Research Centre for Nanoscience and Nanotechnology of PolyU, Prof. Benny CHEUNG, Director of State Key Laboratory of Ultra-precision Machining Technology of PolyU and many others attended the visit and conference. The delegation visited the State Key Laboratory of Chemical Biology and Drug Discovery, the State Key Laboratory of Ultra-precision Machining Technology and the PolyU Design Show.