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Reduction of scour around circular piers using collars
No full textYesRiver dynamics and sediment transport play an important role in river bed morphology. Building a bridge pier along the river alters the cross-section of the river and causes the change in flow processes. These changes are mainly responsible for pier scour. In this paper, the usage of collars to reduce scour around circular piers has been investigated. The collars with different diameters and depth positions have been studied using previous data and additional data collected in the present study to assess their effectiveness in reducing scour. Using a wide range of measured data, an empirical equation to compute the maximum scour depth around the circular piers in the presence of collars has been proposed. The proposed equation has been validated and proven to be applicable to a wide range of pier layouts. It has been found that the maximum efficiency can be achieved by fixing the collar at bed level and adopting a collar diameter 1.5-2.5 times of pier diameter
Semi-analytical solution of solute dispersion model in semi-infinite media
No full textNoThe advection-dispersion equation (ADE) is one of the most widely used methods for estimating natural stream pollution at different locations and times. In this paper, variational iteration method (VIM) is utilized to obtain a semianalytical solution for 1D ADE in a temporally dependent solute dispersion within uniformsteady flow. Through a computational validation, the effect of different parameters such as uniform flow velocity and dispersion coefficient on the solute concentration values has been investigated. Results show that the change in velocity has a strong effect on fluid density variation. However, when the diffusion coefficient has been increased, the change in flow and velocity behaviors is negligible. To verify the proposed semianalytical solution, the results were compared to analytical solutions and errors were found to be <0.7% in all simulations
Self-Fluorescent Lone Tryptophan Nanoparticles as Theranostic Agents Against Alzheimer's Disease.
No full textNoAggregation of β-amyloid (Aβ42) peptide in the neural extracellular space leads to cellular dysfunction, resulting in Alzheimer's disease (AD). The hydrophobic core of the amyloidogenic Aβ42 peptide contains aromatic residues that play an important role in the self-assembly and subsequent aggregation of the peptide. Hence, targeting these hydrophobic core residues by potent low molecular agents can be a promising therapeutic approach toward AD. In the current work, we have developed self-fluorescent solo tryptophan nanoparticles (TNPs) as nanotheranostic systems against AD. We demonstrated that TNPs could significantly inhibit as well as disrupt the fibrils formed by both Aβ42 peptide and another reductionist approach-based amyloid model dipeptide, phenylalanine-phenylalanine (FF). More importantly, these nanostructures were nontoxic to neural cells and could protect the neurons from Aβ42 peptide and FF aggregate-induced cytotoxicity. In addition, efficacy studies performed in animal model further revealed that the TNPs could rescue spatial and learning memory in intracerebroventricular streptozotocin-administration-induced AD phenotype in rats. Moreover, our pharmacokinetics study further established the BBB permeability and brain delivery potency of TNPs. The inherent excellent fluorescent properties of these nanoparticles could be exploited further to use them as imaging modalities for tagging and detecting FF and Aβ42 peptide fibrils. Overall, our results clearly illustrated that the solo TNPs could serve as promising nanotheranostic agents for AD therapy
Inclusive hyper- to dilute-concentrated suspended sediment transport study using modified rouse model: parametrized power-linear coupled approach using machine learning
Get PDFYesThe transfer of suspended sediment can range widely from being diluted to being hyperconcentrated, depending on the local flow and ground conditions. Using the Rouse model and the
Kundu and Ghoshal (2017) model, it is possible to look at the sediment distribution for a range of
hyper-concentrated and diluted flows. According to the Kundu and Ghoshal model, the sediment
flow follows a linear profile for the hyper-concentrated flow regime and a power law applies for the
dilute concentrated flow regime. This paper describes these models and how the Kundu and
Ghoshal parameters (linear-law coefficients and power-law coefficients) are dependent on sediment
flow parameters using machine-learning techniques. The machine-learning models used are
XGboost Classifier, Linear Regressor (Ridge), Linear Regressor (Bayesian), K Nearest Neighbours,
Decision Tree Regressor, and Support Vector Machines (Regressor). The models were implemented
on Google Colab and the models have been applied to determine the relationship between every
Kundu and Ghoshal parameter with each sediment flow parameter (mean concentration, Rouse
number, and size parameter) for both a linear profile and a power-law profile. The models correctly
calculated the suspended sediment profile for a range of flow conditions ( 0.268 ≤ 50 ≤
2.29 , 0.00105
3 ≤ particle density ≤ 2.65
3 , 0.197
≤ ≤ 96
, 7.16
≤ ∗ ≤
63.3
, 0.00042 ≤ ̅≤ 0.54), including a range of Rouse numbers (0.0076 ≤ ≤ 23.5). The models
showed particularly good accuracy for testing at low and extremely high concentrations for type I
to III profiles
A Compact Wideband Circularly Polarized Planar Monopole Antenna with Axial Ratio Bandwidth Entirely Encompassing the Antenna Bandwidth
Get PDFYesThe antenna presented in this study is a compact wideband monopole with wideband circular polarization that can be used across the whole antenna bandwidth. A rectangular C-shaped patch is partially covered by a ground plane in the proposed planar monopole antenna. Inserting a rectangular stub to the ground plane, etching a slit at the antenna patch, and adding a semicircular stub at the top of the antenna feed line increase the antenna impedance bandwidth (BW) and axial ratio bandwidth (ARBW). An FR4 substrate with overall dimensions of 25 mm×25 mm×1.6 mm is used to create the antenna. The antenna's observed impedance BW is 70% (4.55 GHz in the 4.3-8.85 GHz band), while the measured broadside ARBW is improved to a value of 82.2 percent (5.3 GHz along the range 3.8-9.1 GHz). The impedance BW is perfectly covered by the ARBW; hence the antenna can be considered circularly polarized throughout its operational spectrum. Within the antenna BW, the measured gain is greater than 1.5 dB
Generation and Use of Functional Hydrogels That Can Rapidly Sample Infected Surfaces
No full textYesThis paper outlined our method for developing polymer-linked contact lens type materials for rapid detection and differentiation of Gram-positive, Gram-negative bacteria and fungi in infected corneas. It can be applied to both model synthetic or ex-vivo corneal models and has been successfully trialed in an initial efficacy tested animal study. First a hydrogel substrate for the swab material is selected, we have demonstrated selective swabs using a glycerol monomethacrylate hydrogel. Alternatively any commercial material with carboxylic acid functional groups is suitable but risks nonspecific adhesion. This is then functionalised via use of N-hydroxysuccinimide reaction with amine groups on the specified highly branched polymer ligand (either individually gram negative, gram positive or fungal binding polymers or a combination of all three can be employed for desired sensing application). The hydrogel is then cut into swabs suitable for sampling, used, and then the presence of gram positive, game negative and fungi are disclosed by the sequential addition of dyes (fluorescent vancomycin, fluorescein isothiocyanate and calcofluor white).
In summary this method presents:
Method to produce glycerol monomethacrylate hydrogels to minimize nonspecific binding
Methods of attaching pathogen binding highly branched polymers to produce selective hydrogel swabs
Method for disclosing bound pathogens to this swab using sequential dye additio
Robotic employees vs. human employees: Customers’ perceived authenticity at casual dining restaurants
Get PDFYesCost-saving and sanitation considerations and the challenge of labor shortages have catalyzed the application of service robots in restaurants. Although service robots can perform multiple roles and functions, more research attention is needed in hospitality contexts on how different combinations of using robots and humans at different product/service layers may influence customers’ experiences and behavioral intentions. Building on the literature of product level theory and authenticity, this study empirically investigated this issue with data collected from 364 customers in China. The results show that the use of robots in core and facilitating product levels is less effective in improving consumers’ perceived service and brand authenticity. Consumers’ perceived service authenticity positively influences their brand authenticity and repurchase intention. Consumers’ perceived brand authenticity only positively affects their repurchase intention. Both theoretical and managerial implications are discussed in this paper.Research Development Fund Publication Prize Award winner, July 202
The belt and road initiative (BRI): A mechanism to achieve the ninth sustainable development goal (SDG)
No full textYesCongruent with economic stability and environmental sustainability, the ninth Sustainable Development Goal (SDG - Industry, Innovation and Infrastructure) plays a crucial role in undergirding the industrial revolution. Conversely, it is inevitably complex for underdeveloped and emerging economies to meet the ninth SDG's 2030 agenda due to a lack of sufficient financial resources and the slow adoption of technology. With China expanding its Belt and Road Initiatives (BRIs) globally, mainly few findings espouse the significant link between BRI and the ninth SDG, and its probable impact remains understudied. Hence, a considerable gap yet exists in contemporary understanding of the impact of BRI on sustainability. Therefore, we conducted an exploratory study on six different countries (Algeria, Ghana, Indonesia, Malaysia, Nigeria and Palestine) to investigate the role of the BRI in achieving the ninth SDG. Face-to-face interviews and focus group discussions were applied. This qualitative data collection technique involved 26 participants representing industry experts and academic researchers. All interviews were recorded, transcribed, translated and thematically analysed. The result showed a significant progressive impact of BRI on the ninth SDG, and that the development of sustainable infrastructure is a key antecedent of the BRI policy enforcement in the six countries explored. The result also showed positive and negative spillover effects of BRI projects in the six countries. Government and Policymakers should design and enforce pro-growth and sustainable strategies to facilitate continuous implementation of policies that would align the execution of the BRI projects to bolster achievement of the ninth SDG
Perinatal depression: Factors affecting help-seeking behaviours in asylum seeking and refugee women. A systematic review
Get PDFYesPurpose
Perinatal depression is one of the most commonly diagnosed mental health conditions in the general maternity population but whilst the prevalence is thought to be much higher in asylum seeking and refugee (AS&R) women, it is less frequently identified and diagnosed by health care professionals.
Method
A systematic review was undertaken to address ‘what factors influence help-seeking behaviours in asylum seeking and refugee women with symptoms of perinatal depression’. The review focussed on women accessing care in high income countries. 12 studies met the eligibility criteria and a narrative synthesis was undertaken resulting in two main themes: women's perceptions of depression and access to healthcare and support services.
Results
Findings indicated that many of the influences on help-seeking were also present in the general population and women from ethnic minority populations, with the exception of migration experiences; but that women from a AS&R may experience more of these barriers, exacerbating inequality in access to and engagement with healthcare.
Conclusion
Further research is needed to provide more detailed insight into the experiences of asylum seeking and refugee women to identify ways that barriers in help-seeking can be addressed
Concordance of objectively-detected retinal nerve fiber bundle defects in en face OCT images with conventional structural and functional changes in glaucoma.
Get PDFYesTo assess how objectively-detected defects of retinal nerve fibre bundle (RNFB) reflectance in en face OCT images relate to circumpapillary retinal nerve fibre layer thickness (cpRNFLT) and visual field defects.
Cross-sectional study.
16 participants with early-glaucoma and 29 age-similar healthy controls, among which 22 had usable en face images to establish normative levels of RNFB reflectance.
All participants underwent cpRNFLT scans, visual field examination and wide-field OCT. En face reflectivity was assessed objectively using the Summary of Multiple Anatomically-Adjusted Slabs (SMAS) method. En face defects were deemed concordant with cpRNFLT when they had at least one cpRNFLT point with