Entropy 2021: The Scientific Tool of the 21st Century

Frailty in older adults is characterised by dysregulation in multiple physiological systems. The frailty phenotype is defined on the basis of exhaustion, unexplained weight loss, weakness, slowness and low physical activity (one or two: pre-frail; 3 or more: frail). Our aim was to explore if increasing frailty is associated with the complexity of resting state physiological signals in a large cohort of community-dwelling older adults, enrolled as part of The Irish Longitudinal Study on Ageing (TILDA). Systolic/diastolic blood pressure (SBP/DBP), mean arterial pressure (MAP), and heart rate (HR) were measured in 3,154 participants (66.2% non-frail; 31.3% pre-frail; 2.5% frail) using a Finometer? device at 200Hz; and frontal lobe oxygenation (tissue saturation index (TSI)) in 2,749 individuals (66.3% non-frail; 31.3% pre-frail; 2.4% frail) at 50Hz using an Artinis Portalite? near infrared spectroscopy system. Data were acquired continuously during five minutes of supine rest and the last minute (downsampled to 5Hz) was utilised in these analyses. The complexity of signals was quantified using approximate entropy (ApEn) with m=2 and an optimal r derived via multiple iterations, implemented in Matlab (R2019a). Statistical analysis was performed using multivariate linear regression models in STATA (v14.1), controlling for age, sex, education, antihypertensive medication, diabetes, number of cardiovascular conditions, smoking, alcohol, and depression. Mean age for both groups was 64.3?8.1 years and 53% were female. The pre-frail group was associated with significantly increased ApEn for all measures investigated (sBP: ?=0.014, P?0.001; dBP: ?=0.009, P=0.002; MAP: ?=0.012, P?0.001; HR: ?=0.011, P=0.003; TSI: ?=0.009, P=0.002). Likewise, the frail group was associated with further increased ApEn for all measures investigated (sBP: ?=0.031, P=0.002; dBP: ?=0.028, P=0.003; MAP: ?=0.038, P?0.001; HR: ?=0.034, P=0.001; TSI: ?=0.018, P=0.029). Approximate entropy seems to be a sensitive method to capture increasing signal complexity in multiple physiological systems associated with the frailty phenotype during resting state

Applications of CCD-Thermoreflectance to Thin Film Thermoelectric Characterisation

In recent years the microelectronics industry has been calling out for alternative thermal cooling approaches due to increased heat fluxes in microscale electronic and photonic devices. One such approach is to use thin film thermoelectric devices (TECs) due to their reliable solid-state design, low energy consumption and high speed. This thesis is centred around the use of CCD - thermoreflectance imaging (CCD-TR) as a characterisation tool in the development of thin film thermoelectric devices. Various new methodologies for CCD TR were developed including the introduction of new correction factors for shutter time and DC offsets that eliminate errors in the standard approach. This includes a new method to indirectly measure the Seebeck coefficient of a thermoelectric device if thermal imaging through CCD-TR is taken of the topmost contact. To demonstrate this, CCD-TR imaging is carried out on a TEC designed for integration in a photonic package. Annealing steps were carried out on this device, which by CCD-TR imaging was shown to increase its Seebeck coefficient and its predicted heat pumping capacity. CCD-TR was adapted for CW laser induced heating and demonstrated as a viable method to measure the thermal conductivity of thin films and also describe the dewetting temperatures of metallic gold thin films on a quartz substrate. In general, this technique allows a known heat flux to be applied at the microscale. A full thermal characterisation of a thin film electrodeposited TEC material is demonstrated using CCD-TR. This characterisation yielded a record breaking 720 Wcm-2 cooling heat flux for a thin film thermoelectric device. This heat flux comes from the ability of the TEC to be functionally thinned while minimising its contact resistance through cleaning steps during fabrication. This demonstrates that relatively simple techniques such as electrodeposition can rival more complex and demanding MBE and MOCVD grown superlattices

Children’s Ethno-National Flag Categories in Three Divided Societies

Flags are conceptual representations of group membership that can prime nationalism and allegiance to one’s group (Butz, 2009; Firth, 1973). Flags of rival groups in post-accord societies may fuel further divisions (Bryson & McCartney, 1994; Holmes & Cagle, 2000; Jarman, 1997; Morris, 2005). Yet, in settings of historic intergroup conflict, flags may also symbolize unity and peace. For instance, in Bolivia, the Wiphala flag holds dual status with the Bolivian flag; flown side by side, these flags symbolize unity with the indigenous minority population (Flesken, 2014). In Kosovo, the creation of a new flag after the break from Yugoslavia symbolized the formation of a new subordinate national identity—the Kosovar identity (Maloku, Derks, Van Laar, & Ellemers, 2016). Given these multiple meanings and representations, investigating children’s understanding of the symbolic content of flags representing conflict-related groups and national allegiances can shed light on early conceptions of nationality. Framed by Social Identity Development Theory (SIDT; Nesdale, 1999; 2004), we investigate the development of categorization of, and preferences for, ethnic flags in three post-accord societies: Northern Ireland (NI), the Republic of North Macedonia (RNM), and Kosovo.School of Psychology Research Incentivisation SchemeDepartment for the Economy (DfE) - Global Challenge Research Fund (GCRF)British Psychological Society, Social Psychology Section, Pump-priming and Dissemination Fun

Populations and problems evaluated with functional assessment

Functional assessment is a technique consisting of a set of procedures that define the relationship between events in the environment and specific target behaviors. The purpose of functional assessment is to identify maintaining contingencies for challenging behavior in an individual s environment. This chapter provides an overview of populations evaluated with functional assessment, which includes the following: Autism Spectrum Disorder, Intellectual Disability, Emotional Behavioral Disorder, Attention-Deficit/Hyperactivity Disorder, Fragile X Syndrome, Angelman Syndrome, Prader-Willi Syndrome, Smith-Magenis Syndrome, Lesch-Nyhan Syndrome, Acquired Brain Injury, Typically Developing Children, Children at Risk of Developmental Disabilities, Children with Prenatal Drug Exposure, and Children who use Wheelchairs. The subsequent part of this chapter will focus on the behaviors and problems evaluated with functional assessment, which include the following: aggression, self-injurious behavior, stereotypy, bizarre speech, skin picking, hand mouthing, feeding problems, elopement, noncompliance and disruptive behavior, multiple typographies of problem behavior, sleep problems, and happiness behaviors. An extensive review of the research will provide the reader with the range of possible uses of functional assessment.Peer reviewed2023-03-2

Development of Novel Acyl Thiol-ene Mediated Peptide Ligation Strategies

This thesis, entitled Development of Novel Acyl Thiol-ene Mediated Peptide Ligation Strategies is composed of six chapters. Chapter 1 provides an introductory overview of the fields of amide synthesis and peptide ligation. Particular emphasis is given to the emergence of Native Chemical Ligation and the extended methodologies developed to further the reach of this powerful synthetic technique. The limitations of these approaches, with regards to thioester formation via thioesterification, are also described. In addition, Chapter 1 details the application of thiol-ene chemistries to the synthesis and derivatisation of biomolecules, with specific attention given to the extent of the reaction within the field of peptide chemistry. The use of the acyl thiol-ene reaction to synthesise thioesters in organic syntheses is also detailed, along with the established chemical methods to access peptide thioacids. Chapter 1 is concluded with a brief description of the work described in this thesis and the overarching aims of this work. Chapter 2 details efforts to develop acyl thiol-ene mediated ligation strategies via the synthesis and investigation of auxiliary bearing dipeptide systems. Unsaturated auxiliaries affixed to amino acid side-chains or α-amino groups of native peptides would permit the rapid formation of peptidic thioesters via acyl thiol-ene addition of a peptide thioacid component. S-to-N acyl transfer of the resulting thioester and subsequent auxiliary cleavage would furnish native amide products. Unfortunately, none of the auxiliary systems investigated possessed the necessary balance of synthetic accessibility, acyl transfer reliability and reaction stability to prompt their insertion into larger systems. Chapter 3 describes the synthesis of derivatives of unsaturated unnatural amino acids vinylglycine and L-3,4-didehydrovaline inspired by literature precedent. Significant synthetic optimisation was required in the case of L-3,4-didehydrovaline. Nonetheless, routes to access gram quantities of N-tert-butyloxycarbonyl protected vinylglycine and L-3,4-didehydrovaline are detailed. The synthesis of unsaturated dipeptides from these precursors and investigation of their reactivity towards acyl thiol-ene addition with a range of amino acid thioacids is outlined. S-to-N acyl transfer and subsequent derivatisation of thioesters to native tripeptide products is also demonstrated. Chapter 4 details efforts to synthesise two fragments of the therapeutically valuable peptide human parathyroid hormone. The synthesis of unsaturated decapeptides bearing vinylglycine and L-3,4-didehydrovaline functionalities via solid phase peptide synthesis is described. Efforts to synthesise peptide thioacids through literature protocols are also detailed. Chapter 5 concludes the work in this thesis and briefly outlines possible future work. Chapter 6 describes the general experimental procedures employed in the course of this work and characterisation data of the compounds synthesised during the preparation of this thesis

Reducing drug-use harms among higher education students: MyUSE contextual-behaviour change digital intervention development using the Behaviour Change Wheel

Background: Digital harm-reduction interventions typically focus on people with severe drug-use problems, yet these interventions have moderate effectiveness on drug-users with lower levels of risk of harm. The difference in effectiveness may be explained by differences in behavioural patterns between the two groupings. Harnessing behavioural theories to understand what is at the core of drug-use behaviours and mapping the content of new interventions, may improve upon the effectiveness of interventions for lower-risk drug-users. To the best of our knowledge, this is the first study to systematically apply the Behaviour Change Wheel (BCW) approach to understand the components, influencing capabilities, opportunities, and motivations (COM-B) of higher education students to change their drug-use behaviors. It is also the first study which identifies specific patterns of behaviours that are more responsive to harm reduction practices through the use of the Theoretical Domain Framework (TDF). Methods: We employed an explanatory sequential mix-method design. We first conducted an on-line survey and a Delphi exercise to understand the factors influencing COM-B components of higher education students to change their drug-use. Subsequently, we mapped all evidence onto the COM-B components and the TDF domains to identify clusters of behaviours to target for change, using a pattern-based discourse analysis. Finally, a series of multidisciplinary group meetings identified the intervention functions—the means by which the intervention change targeted behaviours and the Behavioural Change Techniques (BCTs) involved using the behaviour change technique taxonomy (v.1). Results: Twenty-nine BCTs relevant to harm-reduction practices were identified and mapped across five intervention functions (education, modelling, persuasion, incentivization, and training) and five policy categories (communication/marketing, guidelines, regulation, service provision, and environmental/social planning). These BCTs were distributed across eight identified saturated clusters of behaviours MyUSE intervention attempts to change. Conclusions: The BCTs, identified, will inform the development of a digitally delivered behaviour change intervention that focuses on increasing mindful decision-making with respect to drug-use and promotes alternatives to drug-use activities. The findings can also inform implementation scientists in applying context-specific harm-reduction practices in higher education. We present examples of how the eight identified clusters of target behaviours are mapped across the COM-B components and the TDF, along with suggestions of implementation practices for harm reduction at student population level

Sense of Belonging: The Intersectionality of Self-Identified Minority Status and Gender in Undergraduate Computer Science Students

The 2020 United Kingdom and Ireland Computing Education Research (UKICER 2020) Conference, Virtual Conference, 3-4 September 2020Creating inclusive learning environments for all students is of primary importance. Student sense of belonging is an important part of this. However, sense of belonging can show variations according to factors such as ethnicity and gender as well as influencing attributes such as motivation and persistence. We utilised a survey adapted from the "Math Sense of Belonging Scale"to examine the relationship between undergraduate computer science students\u27 sense of belonging, gender identity, and self-declared minority status. We observed a lower sense of belonging in students who identified as women who also self-identified as being part of a minority group. However, students who identified as women who did not identify as belonging to a minority had a sense of belonging comparable to those identifying as men. Our results provide insight that may help us improve the sense of belonging of our undergraduate students, particularly those identifying as women and as belonging to a minority in computer science. It has also brought to our attention that action needs to be taken to mitigate the potentially disproportionately negative consequences that COVID-19 may have on these students due to reduced opportunities for social interaction and the negative impact that this has on sense of belonging

An investigation of links between metabolic rate and feed efficiency in European sea bass Dicentrarchus labrax

Feed efficiency (FE) is the amount of body weight gain for a given feed intake. Improving FE through selective breeding is key for sustainable finfish aquaculture but its evaluation at individual level is technically challenging. We therefore investigated whether individual routine metabolic rate (RMR) was a predictor of individual FE in the European sea bass Dicentrarchus labrax, a major species in European mariculture. The European sea bass has three genetically distinct populations across its geographical range, namely Atlantic Ocean (AT), West Mediterranean (WM) and East Mediterranean (EM). We compared FE and RMR of fish from these three populations at 18°C or 24°C. We held 200 fish (62 AT, 66 WM and 72 EM) in individual aquaria and fed them from ad libitum down to fasting. Feed efficiency was assessed for an ad libitum feeding rate and for a fixed restricted ration (1% of metabolic body weight.day -1, with metabolic body weight = body weight 0.8). After being refed 12 weeks in a common tank, individual RMR was measured over 36h by intermittent flow respirometry. There was a significant effect of temperature whereby fish at 18°C had greater mean FE (P 0.05). Therefore, although the results provide evidence of an association between metabolic rate and FE, RMR was not a predictor of individual FE, for reasons that require further investigation

Reconfigurable helical lattices via topological morphing

Composite materials can enhance morphing and deployable structure capability due to their high degree of tailor ability and their favourable stiffness- and strength-to-weight ratios. One such structure, the bistable helical lattice, is augmented in current work. To date this type of structure, shows promise in aerospace systems which require linear actuation. Herein, morphing capabilities are enhanced by removing traditional mechanical fasteners at the joints, and replacing them with magnets which allow detachment and re-attachment in a controlled, purposeful way. Within a helical lattice structure, joint detachment creates new functionality by allowing a new topology to be formed which is used to convert a linear actuator to one that is curved and then back again, when the joints are reattached. The required force to actuate the topological change is characterised through the use of both finite element analysis and experimental testing. The structural response is observed through the manufacture and testing of a demonstrator which replaces the traditional joints with a series of magnets in order to capture this variable topology behaviour

Semiconductor nanowire arrays for optical sensing: a numerical insight on the impact of array periodicity and density

Recent advances in the nanofabrication and modelling of metasurfaces have shown the potential of these systems in providing unprecedented control over light-matter interactions at the nanoscale, enabling immediate and tangible improvement of features and specifications of photonic devices that are becoming always more crucial in enhancing everyday life quality. In this work, we theoretically demonstrate that metasurfaces made of periodic and non-periodic deterministic assemblies of vertically aligned semiconductor nanowires can be engineered to display a tailored effective optical response and provide a suitable route to realize advanced systems with controlled photonic properties particularly interesting for sensing applications. The metasurfaces investigated in this paper correspond to nanowire arrays that can be experimentally realized exploiting nanolithography and bottom-up nanowire growth methods: the combination of these techniques allow to finely control the position and the physical properties of each individual nanowire in complex arrays. By resorting to numerical simulations, we address the near- and far-field behavior of a nanowire ensemble and we show that the controlled design and arrangement of the nanowires on the substrate may introduce unprecedented oscillations of light reflectance, yielding a metasurface which displays an electromagnetic behavior with great potential for sensing. Finite-difference time-domain numerical simulations are carried out to tailor the nanostructure parameters and systematically engineer the optical response in the VIS-NIR spectral range. By exploiting our computational-methods we set-up a complete procedure to design and test metasurfaces able to behave as functional sensors. These results are especially encouraging in the perspective of developing arrays of epitaxially grown semiconductor nanowires, where the suggested design can be easily implemented during the nanostructure growth, opening the way to fully engineered nanowire-based optical metamaterials