Boulder transport by wave action may exploit thin gaps between the boulder and bedrock platform whereby a lubrication zone reduces the friction coefficient during sliding. We derive an effective mixed-lubrication fric...
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Boulder transport by wave action may exploit thin gaps between the boulder and bedrock platform whereby a lubrication zone reduces the friction coefficient during sliding. We derive an effective mixed-lubrication friction coefficient, depending on boulder speed and the geometry of the lubricated region, and analyse its effect on boulder transport. Mixed lubrication enhances boulder dynamics when moving at a faster speed, the lubricated region is increased, or with fewer separated lubricated regions and smaller boulder aspect ratios. We compare our model against static friction and an empirically-fitted model.
The low molecular weight gelator (LMWG) 1 based on the tripodal benzene-1,3,5-tricarboxamide (BTA) motif, capped with terpyridine (tpy) units, was shown to form supramolecular gels with versatile functionalities such ...
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The low molecular weight gelator (LMWG) 1 based on the tripodal benzene-1,3,5-tricarboxamide (BTA) motif, capped with terpyridine (tpy) units, was shown to form supramolecular gels with versatile functionalities such as self-healing, while the cross-linking of its fibers with d- and f-block metal ions led to modified photophysical properties, the obtained gels were additionally capable of extrusion.
In this paper we demonstrate the first example of a finite translation plane which does not contain a translation hyperoval, disproving a conjecture of Cherowitzo. The counterexample is a semifield plane, specifically...
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In this paper we demonstrate the first example of a finite translation plane which does not contain a translation hyperoval, disproving a conjecture of Cherowitzo. The counterexample is a semifield plane, specifically a Generalised Twisted Field plane, of order 64. We also relate this non-existence to the covering radius of two associated rank-metric codes, and the non-existence of scattered subspaces of maximum dimension with respect to the associated spread.
This article presents the implementation of the canonical Lemaitre and Gurson-Tvergaard-Needleman (GTN) damage models and a more recent phase-field type model within a Lagrangian, geometrically nonlinear, cell-centred...
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This article presents the implementation of the canonical Lemaitre and Gurson-Tvergaard-Needleman (GTN) damage models and a more recent phase-field type model within a Lagrangian, geometrically nonlinear, cell-centred finite volume framework. The proposed segregated solution procedure uses Picard-type defect (deferred) outer corrections, where the primary unknowns are cell-centre displacements and pressures. Spurious zero-energy modes (numerical oscillations in displacement and pressure) are avoided by introducing stabilisation (smoothing) diffusion terms to the pressure and momentum equations. Appropriate scaling of the momentum "Rhie-Chow" stabilisation term is shown to be important in regions of plasticity and damage. To accurately predict damage and fracture in wire drawing where hydrostatic pressure is high, novel variants of the Lemaitre model with crack-closure and triaxiality effects are proposed. The developed methods are validated against the notched round bar and flat notched bar experimental cases and subsequently applied to the analysis of axisymmetric wire drawing. It is shown that the proposed finite volume approach provides a robust basis for predicting damage in wire drawing, where the proposed novel Lemaitre model with crack-closure effects was shown to be the most suitable for predicting experimentally observed fracture.
Hybrid platforms of organic semiconductors and plasmonic metal nanostructures have the potential to form effective optical detection substrates. Here, we report the use of an organic p-type conducting polymer poly(3-h...
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Hybrid platforms of organic semiconductors and plasmonic metal nanostructures have the potential to form effective optical detection substrates. Here, we report the use of an organic p-type conducting polymer poly(3-hexylthiophene-2,5-diyl) combined with plasmon-active silver nanostructures to enhance both Raman and fluorescence signal intensities. This enhancement occurs when optically excited charge from the polymer is transferred to silver, causing an enhancement of the electromagnetic field and leading to an increase in both the Raman and fluorescence signal intensities. This study demonstrates the potential of the organic semiconducting polymer-plasmonic metal nanostructure platform in spectroscopy detection technology.
BackgroundThe transition to adulthood can be a complex time in the lives of young people with cerebral palsy (CP). There is a lack of research examining this period from the perspectives of young people and their ***/...
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BackgroundThe transition to adulthood can be a complex time in the lives of young people with cerebral palsy (CP). There is a lack of research examining this period from the perspectives of young people and their ***/AimsThe review sought to identify challenging experiences during the transition to adulthood from the perspectives of young people with CP and their caregivers and to examine factors that acted as barriers and enablers to positive transition *** systematic literature review of peer-reviewed, empirical studies was completed. Thirteen articles were extracted and analysed using a narrative synthesis *** findings identified challenges for the young people in the areas of independent living, sexuality and relationships, navigating health and social care systems, feeling different from their peers and increasing autonomy. Barriers contributing to negative experiences included overprotective parents and a lack of resources. Greater motor ability, supportive parents and knowledgeable healthcare practitioners enabled positive transition *** transition to adulthood presents multiple challenges as perceived by young people with CP and their caregivers. Both parties require greater support to address these challenges during this time. Further research is required to develop interventions that can support this transition experience.
The use of hyperspectral imaging to investigate food samples has grown due to the improved performance and lower cost of instrumentation. Food engineers use hyperspectral images to classify the type and quality of a f...
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The use of hyperspectral imaging to investigate food samples has grown due to the improved performance and lower cost of instrumentation. Food engineers use hyperspectral images to classify the type and quality of a food sample, typically using classification methods. In order to train these methods, every pixel in each training image needs to be labelled. Typically, computationally cheap threshold-based approaches are used to label the pixels, and classification methods are trained based on those labels. However, threshold-based approaches are subjective and cannot be generalized across hyperspectral images taken in different conditions and of different foods. Here a consensus-constrained parsimonious Gaussian mixture model (ccPGMM) is proposed to label pixels in hyperspectral images using a model-based clustering approach. The ccPGMM utilizes information that is available on some pixels and specifies constraints on those pixels belonging to the same or different clusters while clustering the rest of the pixels in the image. A latent variable model is used to represent the high-dimensional data in terms of a small number of underlying latent factors. To ensure computational feasibility, a consensus clustering approach is employed, where the data are divided into multiple randomly selected subsets of variables and constrained clustering is applied to each data subset;the clustering results are then consolidated across all data subsets to provide a consensus clustering solution. The ccPGMM approach is applied to simulated datasets and real hyperspectral images of three types of puffed cereal, corn, rice, and wheat. Improved clustering performance and computational efficiency are demonstrated when compared to other current state-of-the-art approaches.
Microneedle patches (MNs) hold enormous potential to facilitate the minimally-invasive delivery of drugs and vaccines transdermally. However, the micro-mechanics of skin deformation significantly influence the permeat...
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Microneedle patches (MNs) hold enormous potential to facilitate the minimally-invasive delivery of drugs and vaccines transdermally. However, the micro-mechanics of skin deformation significantly influence the permeation of therapeutics through the skin. Previous studies often fail to appreciate the complexities in microneedleskin mechanical interactions. This may impede the accuracy of MNs pre-clinical assessments. Here, we develop a multiphysics finite element model which simulates the biomechanics of microneedle skin penetration and the subsequent permeation of therapeutics. Employing the aqueous pore path hypothesis, we consider how strain (induced through the insertion of a MN), affects pore geometry in the skin and therefore the diffusion of therapeutics. Our models show that considering the insertion-induced skin deformation alone reduces the transdermal permeation of insulin by 25 %, while considering the effect of strain can reduce the overall permeation by a further 45 % over 24 h. Our model also indicates that once the mechanical strain is removed i.e. through removal or dissolution of the array, the permeation through the skin will recover. Furthermore, our results indicate that the delivery of high molecular weight compounds may be most susceptible to strain-induced changes in drug permeation. These findings could have significant implications for the preferred type of microneedle administration when targeting, for example, intradermal or transdermal delivery. Statement of significance: This manuscript presents an advanced computational model of microneedle insertion into human skin. Here, we adopt a multiphysics modelling strategy, where we predict the influence of microneedle insertion on skin deformation and strain and how that influences subsequent therapeutic permeation through the skin. Our model predicts that whether or not the microneedle remains in situ, the resultant change in tissue deformation and strain has a major impact on how quickly the
This paper presents an adaption of the finite-element based beam-to-beam contact interactions into a finite volume numerical framework. A previous work of the same authors, where a cell-centred based finite volume imp...
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This paper presents an adaption of the finite-element based beam-to-beam contact interactions into a finite volume numerical framework. A previous work of the same authors, where a cell-centred based finite volume implementation of geometrically exact nonlinear Simo-Reissner beams was developed, is used as an underlying mathematical model. An implicit contact procedure is developed for both point-to-point and line-to-line beam frictionless contact interactions, and is implemented using the cell-centred finite volume method. To enforce the contact constraint, both penalty method and augmented-Lagrangian based techniques are used. A total of six numerical benchmark cases for point and line beam-to-beam contact interactions based on the finite element method are used to verify the numerical results, accuracy and robustness of the developed contact procedure.
BackgroundMost women can produce enough milk to exclusively breastfeed. However, a small cohort are prevented from doing so due to a condition known as primary low milk supply. The aim of the study was to provide new ...
BackgroundMost women can produce enough milk to exclusively breastfeed. However, a small cohort are prevented from doing so due to a condition known as primary low milk supply. The aim of the study was to provide new insights into how mothers with this condition experience help and support from professionals, volunteer support groups, and *** phenomenological analysis was used to explore the lived experiences of nine first-time breastfeeding mothers in Ireland who had primary low milk supply. One-hour interviews were conducted over Zoom between April and October *** with Others, one of four superordinate themes identified in this study, concerns the participants' experiences of receiving professional, voluntary, and partner breastfeeding support. Four sub-themes were identified: Disconnected Encounters, Perceiving Judgement from Others, Being in a Safe Space and Having a Saviour. The encounters of participants with healthcare professionals revealed a lack of rapport, intrusive hands-on support, poor perceived quality of breastfeeding support and a heightened sensitivity to language and tone. Participants expressed that they valued empathy and emotional support from lactation professionals as much as they valued skilled lactation support. Furthermore, participants appeared to experience an enhanced motherhood self-identity and self-acceptance through seeing their experiences mirrored in the experiences of other mothers with primary low milk supply in specialist low milk supply-specific support *** interactions that mothers with primary low milk supply have with various others in their world (healthcare professionals, lactation consultants, volunteer breastfeeding supporters, and partners) can shape how they view themselves and can have a profound impact on their breastfeeding journey. There is a need for greater knowledge and understanding among healthcare professionals of the phenomenon of primary low milk su
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