NobleBlocks

Heriot-Watt University Malaysia

UniversityPutrajaya, Malaysia

Research output, citation impact, and the most-cited recent papers from Heriot-Watt University Malaysia (Malaysia). Aggregated across the NobleBlocks index of 300M+ scholarly works.

Total works
6.7K
Citations
164.3K
h-index
145
i10-index
3.5K
Also known as
Heriot-Watt University Malaysia

Top-cited papers from Heriot-Watt University Malaysia

Wireless Power Transfer—An Overview
Zhen Zhang, Hongliang Pang, Apostolos Georgiadis, Carlo Cecati
2018· IEEE Transactions on Industrial Electronics1.7Kdoi:10.1109/tie.2018.2835378

Due to limitations of low power density, high cost, heavy weight, etc., the development and application of battery-powered devices are facing with unprecedented technical challenges. As a novel pattern of energization, the wireless power transfer (WPT) offers a band new way to the energy acquisition for electric-driven devices, thus alleviating the over-dependence on the battery. This paper presents an overview of WPT techniques with emphasis on working mechanisms, technical challenges, metamaterials, and classical applications. Focusing on WPT systems, this paper elaborates on current major research topics and discusses about future development trends. This novel energy transmission mechanism shows significant meanings on the pervasive application of renewable energies in our daily life.

Nanoparticle Uptake by the Rat Gastrointestinal Mucosa: Quantitation and Particle Size Dependency
Praful U. Jani, Gavin Halbert, John Langridge, Alexander T. Florence
1990· Journal of Pharmacy and Pharmacology919doi:10.1111/j.2042-7158.1990.tb07033.x

Polystyrene microspheres in the size range 50 nm to 3 microns were fed by gavage to female Sprague Dawley rats daily for 10 days at a dose of 1.25 mg/kg-1. Previous histological evidence of the uptake of these particles and their absorption across the gastrointestinal tract and passage via the mesentery lymph supply and lymph nodes to the liver and spleen was confirmed by analysis of tissues for the presence of polystyrene by gel permeation chromatography. Measurement of radioactivity of tissues following administration of 100 nm and 1 micron I125-labelled polystyrene latex particles for 8 days was corroborative although less secure because of the potential lability of the labelled particles. The extent of absorption of 50 nm particles under the conditions of these experiments was 34% and of the 100 nm particles 26% (as measured by determination of polystyrene content), of which total, about 7% (50 nm) and 4% (100 nm), was in the liver, spleen, blood and bone marrow. Particles larger than 100 nm did not reach the bone marrow, and those larger than 300 nm were absent from blood. No particles were detected in heart or lung tissue.

Microbial Extracellular Polymeric Substances (EPSs) in Ocean Systems
Alan W. Decho, Tony Gutiérrez
2017· Frontiers in Microbiology737doi:10.3389/fmicb.2017.00922

Microbial cells (i.e. bacteria, archaea, microeukaryotes) in oceans secrete a diverse array of large molecules, collectively called extracellular polymeric substances (EPS) or simply exopolymers. These secretions facilitate attachment to surfaces that lead to the formation of structured 'biofilm' communities. In open-water environments, they also lead to formation of organic colloids, and larger aggregations of cells, called ‘marine snow’. Secretion of EPS is now recognized as a fundamental microbial adaptation, occurring under many environmental conditions, and one that influences many ocean processes. This relatively recent realization has revolutionized our understanding of microbial impacts on ocean systems. EPS occur in a range of molecular sizes, conformations and physical/chemical properties, and polysaccharides, proteins, lipids and even nucleic acids are actively-secreted components. Interestingly, however, the physical ultrastructure of how individual EPS interact with each other is poorly-understood. Together, the EPS matrix molecules form a three-dimensional architecture from which cells may localize extracellular activities and conduct cooperative/ antagonistic interactions that cannot be accomplished efficiently by free-living cells. EPS alter optical signatures of sediments and seawater, and are involved in biogeomineral precipitation and the construction of microbial macrostructures, and horizontal-transfers of genetic information. In the water-column, they contribute to the formation of marine snow, transparent exopolymer particles (TEP), sea-surface microlayer biofilm, and marine oil snow (MOS). Excessive production of EPS occurs during later-stages of phytoplankton blooms as an excess metabolic byproduct and releases a carbon pool that transitions among dissolved-, colloidal-, and gel-states. Some EPS are highly-labile carbon forms, while other forms appear quite refractory to degradation. Emerging studies suggest that EPS contribute to efficient trophic-transfer of environmental contaminants, and may provide a protective refugia for pathogenic cells within marine systems; one that enhances their survival/persistence. Finally, these secretions are prominent in ‘extreme’ environments ranging from sea-ice communities to hypersaline systems to the high-temperatures/pressures of hydrothermal-vent systems. This overview summarizes some of the roles of exopolymer in oceans.

Tenth SPE Comparative Solution Project: A Comparison of Upscaling Techniques
Michael Andrew Christie, Martin J. Blunt
2001· SPE Reservoir Evaluation & Engineering730doi:10.2118/72469-pa

Summary This paper presents the results of the 10th SPE Comparative Solution Project on Upscaling. Two problems were chosen. The first problem was a small 2D gas-injection problem, chosen so that the fine grid could be computed easily and both upscaling and pseudoization methods could be used. The second problem was a waterflood of a large geostatistical model, chosen so that it was hard (though not impossible) to compute the true fine-grid solution. Nine participants provided results for one or both problems.

Perspectives on ethnic and racial disparities in Alzheimer's disease and related dementias: Update and areas of immediate need
Ganesh M. Babulal, Yakeel T. Quiroz, Benedict C. Albensi, Eider M. Arenaza‐Urquijo +4 more
2018· Alzheimer s & Dementia550doi:10.1016/j.jalz.2018.09.009

Alzheimer's disease and related dementias (ADRDs) are a global crisis facing the aging population and society as a whole. With the numbers of people with ADRDs predicted to rise dramatically across the world, the scientific community can no longer neglect the need for research focusing on ADRDs among underrepresented ethnoracial diverse groups. The Alzheimer's Association International Society to Advance Alzheimer's Research and Treatment (ISTAART; alz.org/ISTAART) comprises a number of professional interest areas (PIAs), each focusing on a major scientific area associated with ADRDs. We leverage the expertise of the existing international cadre of ISTAART scientists and experts to synthesize a cross-PIA white paper that provides both a concise "state-of-the-science" report of ethnoracial factors across PIA foci and updated recommendations to address immediate needs to advance ADRD science across ethnoracial populations.

An Introduction to Computational Stochastic PDEs
Gabriel J. Lord, Catherine E. Powell, Tony Shardlow
2014· Cambridge University Press eBooks549doi:10.1017/cbo9781139017329

This book gives a comprehensive introduction to numerical methods and analysis of stochastic processes, random fields and stochastic differential equations, and offers graduate students and researchers powerful tools for understanding uncertainty quantification for risk analysis. Coverage includes traditional stochastic ODEs with white noise forcing, strong and weak approximation, and the multi-level Monte Carlo method. Later chapters apply the theory of random fields to the numerical solution of elliptic PDEs with correlated random data, discuss the Monte Carlo method, and introduce stochastic Galerkin finite-element methods. Finally, stochastic parabolic PDEs are developed. Assuming little previous exposure to probability and statistics, theory is developed in tandem with state-of-the-art computational methods through worked examples, exercises, theorems and proofs. The set of MATLAB codes included (and downloadable) allows readers to perform computations themselves and solve the test problems discussed. Practical examples are drawn from finance, mathematical biology, neuroscience, fluid flow modelling and materials science.

Presentation of depression in autism and Asperger syndrome
Mary E. Stewart, Louise Barnard, Joanne Pearson, Reem Hasan +1 more
2006· Autism526doi:10.1177/1362361306062013

Depression is common in autism and Asperger syndrome, but despite this, there has been little research into this issue. This review considers the current literature on the prevalence, presentation, treatment and assessment of depression in autism and Asperger syndrome. There are diagnostic difficulties when considering depression in autism and Asperger syndrome, as the characteristics of these disorders, such as social withdrawal and appetite and sleep disturbance, are also core symptoms of depression. Impaired verbal and non-verbal communication can mask the symptoms of depression. Symptoms associated with autism and Asperger syndrome such as obsessionality and self-injury may be increased during an episode of depression. There is a clear need to develop specific tools both for diagnostic purposes and for measurement of depression in autism and Asperger syndrome in order to help alleviate the distress caused by this treatable illness.

Vector Vortex Beam Generation with a Single Plasmonic Metasurface
Fuyong Yue, Dandan Wen, Jingtao Xin, Brian D. Gerardot +2 more
2016· ACS Photonics480doi:10.1021/acsphotonics.6b00392

Abstract Despite a plethora of applications ranging from quantum memories to high-resolution lithography, the current technologies to generate vector vortex beams (VVBs) suffer from less efficient energy use, poor resolution, low damage threshold, and bulky size, preventing further practical applications. We propose and experimentally demonstrate an approach to generate VVBs with a single metasurface by locally tailoring phase and transverse polarization distribution. This method features the spin–orbit coupling and the superposition of the converted part with an additional phase pickup and the residual part without a phase change. By maintaining the equal components for the converted part and the residual part, the cylindrically polarized vortex beams carrying orbital angular momentum are experimentally demonstrated based on a single metasurface at subwavelength scale. The proposed approach provides unprecedented freedom in engineering the properties of optical waves with high-efficiency light utilization and a minimal footprint.

Unravelling charge carrier dynamics in protonated g-C3N4 interfaced with carbon nanodots as co-catalysts toward enhanced photocatalytic CO2 reduction: A combined experimental and first-principles DFT study
Wee‐Jun Ong, Lutfi Kurnianditia Putri, Yoong-Chuen Tan, Lling‐Lling Tan +4 more
2017· Nano Research473doi:10.1007/s12274-016-1391-4

In this work, we demonstrated the successful construction of metal-free zerodimensional/ two-dimensional carbon nanodot (CND)-hybridized protonated g-C3N4 (pCN) (CND/pCN) heterojunction photocatalysts by means of electrostatic attraction. We experimentally found that CNDs with an average diameter of 4.4 nm were uniformly distributed on the surface of pCN using electron microscopy analysis. The CND/pCN-3 sample with a CND content of 3 wt.% showed the highest catalytic activity in the CO2 photoreduction process under visible and simulated solar light. This process results in the evolution of CH4 and CO. The total amounts of CH4 and CO generated by the CND/pCN-3 photocatalyst after 10 h of visible-light activity were found to be 29.23 and 58.82 μmol·g catalyst −1 , respectively. These values were 3.6 and 2.28 times higher, respectively, than the amounts generated when using pCN alone. The corresponding apparent quantum efficiency (AQE) was calculated to be 0.076%. Furthermore, the CND/pCN-3 sample demonstrated high stability and durability after four consecutive photoreaction cycles, with no significant decrease in the catalytic activity. The significant improvement in the photoactivity using CND/pCN-3 was attributed to the synergistic interaction between pCN and CNDs. This synergy allows the effective migration of photoexcited electrons from pCN to CNDs via well-contacted heterojunction interfaces, which retards the charge recombination. This was confirmed by photoelectrochemical measurements, and steady-state and time-resolved photoluminescence analyses. The first-principles density functional theory (DFT) calculations were consistent with our experimental results, and showed that the work function of CNDs (5.56 eV) was larger than that of pCN (4.66 eV). This suggests that the efficient shuttling of electrons from the conduction band of pCN to CNDs hampers the recombination of electron–hole pairs. This significantly increased the probability of free charge carriers reducing CO2 to CH4 and CO. Overall, this study underlines the importance of understanding the charge carrier dynamics of the CND/pCN hybrid nanocomposites, in order to enhance solar energy conversion.

Uptake, Whole-Body Distribution, and Depuration of Nanoplastics by the Scallop Pecten maximus at Environmentally Realistic Concentrations
Maya Al-Sid-Cheikh, Steve Rowland, K.A. Stevenson, Claude Rouleau +2 more
2018· Environmental Science & Technology396doi:10.1021/acs.est.8b05266

Abstract Previous studies of uptake and effects of nanoplastics by marine organisms have been conducted at what may be unrealistically high concentrations. This is a consequence of the analytical challenges in tracking plastic particles in organisms at environmentally relevant concentrations and highlights the need for new approaches. Here, we present pulse exposures of 14C-radiolabeled nanopolystyrene to a commercially important mollusk, Pecten maximus, at what have been predicted to be environmentally relevant concentrations (<15 μg L–1). Uptake was rapid and was greater for 24 nm than for 250 nm particles. After 6 h, autoradiography showed accumulation of 250 nm nanoplastics in the intestine, while 24 nm particles were dispersed throughout the whole-body, possibly indicating some translocation across epithelial membranes. However, depuration was also relatively rapid for both sizes; 24 nm particles were no longer detectable after 14 days, although some 250 nm particles were still detectable after 48 days. Particle size thus apparently influenced the biokinetics and suggests a need for chronic exposure studies. Modeling extrapolations indicated that it could take 300 days of continued environmental exposure for uptake to reach equilibrium in scallop body tissues although the concentrations would still below 2.7 mg g–1. Comparison with previous work in which scallops were exposed to nonplastic (silver) nanomaterials of similar size (20 nm), suggests that nanoparticle composition may also influence the uptake tissue distributions somewhat.

New speakers of minority languages: the challenging opportunity – Foreword
Bernadette O’Rourke, Joan Pujolar, Fernando Ramallo
2015· International Journal of the Sociology of Language393doi:10.1515/ijsl-2014-0029

Article New speakers of minority languages: the challenging opportunity – Foreword was published on January 1, 2015 in the journal International Journal of the Sociology of Language (volume 2015, issue 231).

Thymic involution and rising disease incidence with age
Sam Palmer, Luca Albergante, Clare Blackburn, T. J. Newman
2018· Proceedings of the National Academy of Sciences386doi:10.1073/pnas.1714478115

For many cancer types, incidence rises rapidly with age as an apparent power law, supporting the idea that cancer is caused by a gradual accumulation of genetic mutations. Similarly, the incidence of many infectious diseases strongly increases with age. Here, combining data from immunology and epidemiology, we show that many of these dramatic age-related increases in incidence can be modeled based on immune system decline, rather than mutation accumulation. In humans, the thymus atrophies from infancy, resulting in an exponential decline in T cell production with a half-life of ∼16 years, which we use as the basis for a minimal mathematical model of disease incidence. Our model outperforms the power law model with the same number of fitting parameters in describing cancer incidence data across a wide spectrum of different cancers, and provides excellent fits to infectious disease data. This framework provides mechanistic insight into cancer emergence, suggesting that age-related decline in T cell output is a major risk factor.

An Ice Age JWST inventory of dense molecular cloud ices
M. K. McClure, W. R. M. Rocha, K. M. Pontoppidan, Nicolas Crouzet +4 more
2023· Nature Astronomy363doi:10.1038/s41550-022-01875-w

Icy grain mantles are the main reservoir of the volatile elements that link chemical processes in dark, interstellar clouds with the formation of planets and the composition of their atmospheres. The initial ice composition is set in the cold, dense parts of molecular clouds, before the onset of star formation. With the exquisite sensitivity of the James Webb Space Telescope, this critical stage of ice evolution is now accessible for detailed study. Here we show initial results of the Early Release Science programme Ice Age that reveal the rich composition of these dense cloud ices. Weak ice features, including 13CO2, OCN−, 13CO, OCS and complex organic molecule functional groups, are now detected along two pre-stellar lines of sight. The 12CO2 ice profile indicates modest growth of the icy grains. Column densities of the major and minor ice species indicate that ices contribute between 2% and 19% of the bulk budgets of the key C, O, N and S elements. Our results suggest that the formation of simple and complex molecules could begin early in a water-ice-rich environment. Using JWST, the molecules seen in planetary atmospheres can be traced back to their cold origins in ices formed in dense interstellar clouds, before the onset of star formation, revealing that chemical diversity and complexity is achieved early.

Introduction to Optical Quantum Information Processing
Pieter Kok, Brendon W. Lovett
2010· Cambridge University Press eBooks348doi:10.1017/cbo9781139193658

Quantum information processing offers fundamental improvements over classical information processing, such as computing power, secure communication, and high-precision measurements. However, the best way to create practical devices is not yet known. This textbook describes the techniques that are likely to be used in implementing optical quantum information processors. After developing the fundamental concepts in quantum optics and quantum information theory, the book shows how optical systems can be used to build quantum computers according to the most recent ideas. It discusses implementations based on single photons and linear optics, optically controlled atoms and solid-state systems, atomic ensembles, and optical continuous variables. This book is ideal for graduate students beginning research in optical quantum information processing. It presents the most important techniques of the field using worked examples and over 120 exercises.

Driving and ‘Passengering’: Notes on the Ordinary Organization of Car Travel
Éric Laurier, Hayden Lorimer, Barry Brown, Owain Jones +4 more
2008· Mobilities330doi:10.1080/17450100701797273

We spend ever‐increasing periods of our lives travelling in cars, yet quite what it is we do while travelling, aside from driving the vehicle itself, is largely overlooked. Drawing on analyses of video records of a series of quite ordinary episodes of car travel, in this paper we begin to document what happens during car journeys. The material concentrates on situations where people are travelling together in order to examine how social units such as families or relationships such as colleagues or friends are re‐assembled and re‐organised in the small‐scale spaces that are car interiors. Particular attention is paid to the forms of conversation occurring during car journeys and the manner in which they are complicated by seating and visibility arrangements. Finally, the paper touches upon the unusual form of hospitality which emerges in car‐sharing.

Strain-Induced Spatial and Spectral Isolation of Quantum Emitters in Mono- and Bilayer WSe2
Santosh Kumar, Artur Kaczmarczyk, Brian D. Gerardot
2015· Nano Letters322doi:10.1021/acs.nanolett.5b03312

Two-dimensional transition metal dichalcogenide semiconductors are intriguing hosts for quantum light sources due to their unique optoelectronic properties. Here, we report that strain gradients, either unintentionally induced or generated by substrate patterning, result in spatially and spectrally isolated quantum emitters in mono- and bilayer WSe2. By correlating localized excitons with localized strain variations, we show that the quantum emitter emission energy can be red-tuned up to a remarkable ∼170 meV. We probe the fine-structure, magneto-optics, and second-order coherence of a strained emitter. These results raise the prospect of strain-engineering quantum emitter properties and deterministically creating arrays of quantum emitters in two-dimensional semiconductors.

Lab-on-a-chip based immunosensor principles and technologies for the detection of cardiac biomarkers: a review
Mazher-Iqbal Mohammed, Marc P. Y. Desmulliez
2010· Lab on a Chip302doi:10.1039/c0lc00204f

This review examines the current state of the art lab-on-a-chip and microfluidic based biosensor technologies used in the detection of cardiac biomarkers. The determination and quantification of blood based, cardiac biomarkers are crucial in the triage and management of a range of cardiac related conditions, where time delay has a major impact on short and longer-term outcomes of a patient. The design and manufacturing of biomarker detection systems are multi-disciplinary in nature and require researchers to have knowledge of both life sciences and engineering for the full potential of this field to be realised. This review will therefore provide a comprehensive overview of chip based immunosensing technology as applied to cardiac biomarker detection, while discussing the potential suitability and limitations of each configuration for incorporation within a clinical diagnostics device suitable for point-of-care applications.

Theory and Experiment of Dual-Mode Microstrip Triangular Patch Resonators and Filters
J.-S. Hong, Shuangming Li
2004· IEEE Transactions on Microwave Theory and Techniques295doi:10.1109/tmtt.2004.825653

In this paper, we report on the results of an investigation into dual-mode operation of microstrip triangular patch resonators and their applications for designing dual-mode bandpass filters. It has been found theoretically that the dual modes can result from the rotation and superposition of a fundamental mode. The characteristics of the dual modes and their mode splitting are described. The applications of this new type of dual-mode microstrip patch resonator in the design of microwave planar filter are presented. A circuit model for operation of this type of filter is proposed. Two- and four-pole filters of this type are demonstrated for the first time. Both theoretical and experimental results are presented.

A THERMODYNAMICALLY CONSISTENT MODEL OF A MUSHY ZONE
R. N. Hills, David E. Loper, Paul Roberts
1983· The Quarterly Journal of Mechanics and Applied Mathematics295doi:10.1093/qjmam/36.4.505

A thermodynamically consistent theory is developed capable of modelling a mushy zone, that is a region of mixed solid phase and liquid phase that can occur during the cooling of a binary alloy. The solid phase forms as a matrix of crystals—often dendrites—which resembles a porous medium of spatially varying permeability. This permeability diminishes in time as further solid freezes out of the liquid phase as it percolates through the matrix. The theory developed here is general enough to incorporate these and other ingredients essential to a proper theoretical treatment of a mushy zone. A simple one-dimensional freezing problem is formulated and solved.

Global supply chain and port/terminal: integration and competitiveness
Dong-Wook Song, Photis M. Panayides
2008· Maritime Policy & Management269doi:10.1080/03088830701848953

Much has been said of the importance of port and terminal integration in the supply chain. Authors have stressed the importance of agility to the port environment, which involves being proactive along supply chains, facilitation of intermodal integration, as well as organizational integration and partnership between ports and users. Despite the well articulated importance of the issues, little has been offered in terms of conceptualizations and empirical evidence of what really is meant by port/terminal integration in the supply chain, how such integration can be measured and quantified as well as the extent to which different ports/terminals in the world are integrated in the supply chain and competitive performance implications arising thereof. This paper aims to make a contribution in this respect by (i) reviewing the relevant literature on supply chain integration and port integration in the supply chain, (ii) conceptualizing measures for port/terminal integration in the supply chain, (iii) empirically testing the influence of port/terminal integration in the supply chain on port competitiveness and (iv) outlining the significance and value of the study for port operators, shipping lines, transport providers and for further research.