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High Electronic Coupling between Cu Complexes and Oxidized Dyes Confirmed by Measurements of Driving Force Dependent Regeneration Kinetics in Minimal Electrolyte System
No full textWe confirm fast regeneration kinetics between copper complexes and oxidized organic dyes and the major contribution of electronic coupling (HDA). The highest efficiency of dye-sensitized TiO2 solar cells has been shown by employing Cu complex redox couples. Various groups have reported a fast regeneration rate of oxidized dyes by Cu complexes giving a low driving force attributed to low reorganization energy (λ), but the effect of HDA has not been evaluated. The values of HDA and λ can be derived from driving force dependent transient absorption (TA) measurements. However, analyzing TA decay using Cu complexes is not trivial because accelerated recombination by the presence of Cu2+ complexes and biphasic TA decay often complicates the analysis. Here we employ 16 Cu1+ and Co2+ complexes and two dyes. To simplify the system, i.e., making a minimal electrolyte system, Cu2+ and Co3+ complexes and a common additive of 4-tert-butylpyridine are not used. From the driving force dependent TA decays of oxidized dyes by both Cu1+ and Co2+ complexes, λ for the combination of the Cu complexes and dyes is found to be about 0.15 eV lower than that of Co complexes. Approximately 3 to 5 times higher HDA values of Cu complexes than those of Co complexes are obtained, which is the dominant factor for faster rates. The values vary with the structure of the molecules, showing the possibility of increasing the HDA values further. The higher HDA values of a Cu complex than that of a Co complex are also reproduced by quantum chemical calculations
The cost of providing care by family and friends (informal care) in the last year of life: A population observational study
No full textIntroduction: Little is known about replacement costs of care provided by informal carers during the last year of life for people dying of cancer and non-cancer diseases. Aim: To estimate informal caregiving costs and explore the relationship with carer and decedent characteristics. Design: National observational study of bereaved carers. Questions included informal end-of-life caregiving into the 2017 Health Survey for England including estimated recalled frequency, duration and intensity of care provision. We estimated replacement costs for a decedent’s last year of life valuing time at the price of a substitutable activity. Spearman rank correlations and multivariable linear regression were used to explore relationships with last year of life costs. Setting/participants: Adult national survey respondents – England. Results: A total of 7997 adults were interviewed from 5767/9612 (60%) of invited households. Estimated replacement costs of personal care and other help were £27,072 and £13,697 per carer and a national cost of £13.2 billion and £15.5 billion respectively. Longer care duration and intensity, older age, death at home (lived together), non-cancer cause of death and greater deprivation were associated with increased costs. Female sex, and not accessing ‘other care services’ were related to higher costs for other help only. Conclusion: We provide a first adult general population estimate for replacement informal care costs in the last year of life of £41,000 per carer per decedent and highlight characteristics associated with greater costs. This presents a major challenge for future universal care coverage as the pool of people providing informal care diminish with an ageing population
Assessing the cooling potential of climate change adaptation measures in rural areas
No full textAtmospheric heat has become a major public concern in a rapidly warming world. Evapotranspiration, however, provides effective land surface cooling during the vegetation period. Adversely, modern cultural landscapes – due to both water and potential evapotranspiration pathways lacking – are increasingly incapable of offering this important benefit. We hypothesised that concerted measures for a revived landscape water retention can fuel plant transpiration, especially during dry periods, and thus contribute to climate change adaptation by stabilising the regional climate. Seeking nature-based ways to an improved landscape water retention, we used the land surface temperature (LST) as a proxy for landscape mesoclimate. For our drought-prone rural study area, we identified potential candidate environmental predictors for which we established statistical relationships to LST. We then, from a set of potential climate change adaptation measures, mapped selected items to potential locations of implementation. Building on that, we evaluated a certain measures’ probable cooling effect using (i) the fitted model and (ii) the expected expression of predictors before and after a hypothetical measure implementation. In the modelling, we took into account the spatial and temporal autocorrelation of the LST data and thus achieved realistic parameter estimates. Using the candidate predictor set and the model, we were able to establish a ranking of the effectiveness of climate adaptation measures. However, due to the spatial variability of the predictors, the modelled LST is site-specific. This results in a spatial differentiation of a measure's benefit. Furthermore, seasonal variations occur, such as those caused by plant growth. On average, the afforestation of arable land or urban brownfields, and the rewetting of former wet meadows have the largest cooling capacities of up to 3.5 K. We conclude that heat countermeasures based on fostering both evapotranspiration and landscape water retention, even in rural regions, offer promising adaptation ways to atmospheric warming
Nanobody engineering: computational modelling and design for biomedical and therapeutic applications
No full textNanobodies, the smallest functional antibody fragment derived from camelid heavy-chain-only antibodies, have emerged as powerful tools for diverse biomedical applications. In this comprehensive review, we discuss the structural characteristics, functional properties, and computational approaches driving the design and optimisation of synthetic nanobodies. We explore their unique antigen-binding domains, highlighting the critical role of complementarity-determining regions in target recognition and specificity. This review further underscores the advantages of nanobodies over conventional antibodies from a biosynthesis perspective, including their small size, stability, and solubility, which make them ideal candidates for economical antigen capture in diagnostics, therapeutics, and biosensing. We discuss the recent advancements in computational methods for nanobody modelling, epitope prediction, and affinity maturation, shedding light on their intricate antigen-binding mechanisms and conformational dynamics. Finally, we examine a direct example of how computational design strategies were implemented for improving a nanobody-based immunosensor, known as a Quenchbody. Through combining experimental findings and computational insights, this review elucidates the transformative impact of nanobodies in biotechnology and biomedical research, offering a roadmap for future advancements and applications in healthcare and diagnostics
Enhanced Thermoelectric Performance of N-Type PbSe Through Semi-Coherent Nanostructure by AgCuTe Alloying
No full textN-type PbSe thermoelectric materials encounter challenges in improving the power factor due to the single-band structure near the Fermi level, which obstructs typical band convergence. The primary strategy for enhancing the thermoelectric figure of merit (ZT) for n-type PbSe involves reducing lattice thermal conductivity (κlat) by introducing various defect structures. However, lattice mismatches resulting from internal defects within the matrix can diminish carrier mobility, thereby affecting electrical transport properties. In this study, n-type AgCuTe-alloyed PbSe systems achieve a peak ZT value of ≈1.5 at 773 K. Transmission electron microscopy reveals nanoprecipitates of Ag2Te, the room temperature second phase of AgCuTe, within the PbSe matrix. Meanwhile, a unique semi-coherent phase boundary is observed between the PbSe matrix and the Ag2Te nanoprecipitates. This semi-coherent phase interface effectively scatters low-frequency phonons while minimizing damage to carrier mobility. Additionally, the dynamic doping effect of Cu atoms from the decomposition of AgCuTe within the matrix further optimize the high-temperature thermoelectric performance. Overall, these factors significantly enhance the ZT across the whole temperature range. The ZT value of ≈1.5 indicates high competitiveness compared to the latest reported n-type PbSe materials, suggesting that these findings hold promise for advancing the development of efficient thermoelectric systems
MOSkin dosimetry for an ultra-high dose-rate, very high-energy electron irradiation environment at PEER
No full textFLASH radiotherapy, which refers to the delivery of radiation at ultra-high dose-rates (UHDRs), has been demonstrated with various forms of radiation and is the subject of intense research and development recently, including the use of very high-energy electrons (VHEEs) to treat deep-seated tumors. Delivering FLASH radiotherapy in a clinical setting is expected to place high demands on real-time quality assurance and dosimetry systems. Furthermore, very high-energy electron research currently requires the transformation of existing non-medical accelerators into radiotherapy research environments. Accurate dosimetry is crucial for any such transformation. In this article, we assess the response of the MOSkin, developed by the Center for Medical Radiation Physics, which is designed for on-patient, real-time skin dose measurements during radiotherapy, and whether it exhibits dose-rate independence when exposed to 100 MeV electron beams at the Pulsed Energetic Electrons for Research (PEER) end-station. PEER utilizes the electron beam from a 100 MeV linear accelerator when it is not used as the injector for the ANSTO Australian Synchrotron. With the estimated pulse dose-rates ranging from (Formula presented.) Gy/s to (Formula presented.) Gy/s and an estimated peak bunch dose-rate of (Formula presented.) Gy/s, MOSkin measurements were verified against a scintillating screen to confirm that the MOSkin responds proportionally to the charge delivered and, therefore, exhibits dose-rate independence in this irradiation environment
Synthesis and properties of cholesteryl-functionalised poly(thiophene)s
No full textConducting polymers (CPs) show promise for future implantable electronics owing to the inherent softness, ionic and electronic conductivity, processibility and the capability to be functionalised. In particular, the use of biofunctionalised poly(thiophenes) at biointerfaces is advantageous as the CP can better interact with cells and proteins, as shown in vitro. Yet very little has been done with cholesteryl functionalisation. Cholesterol naturally intercalates the cell membrane to create highly ordered regions. In material systems, cholesterol can guide isotropic materials into anisotropic phases, which provides an opportunity to synthesise biocompatible polymers with improved molecular ordering that is desirable in bioelectronics. Therefore, the purpose of this work was to investigate the impact of modifying thiophene-based monomers with cholesterol with the intention of creating biocompatible and ordered poly(thiophene)s. This was achieved by exploring suitable monomer structures, addressing the right level of hydrophilicity of the synthesized polymers, and investigating different polymerisation methods
Exploring Environmental and Climatic Complexity between Sunda and Sahul: Insights from Wallacea using Multiproxy Speleothem and Lacustrine Records
No full textThe climatic and environmental history of Wallacea and the surrounding region is understudied. It is a region at the intersection of multiple global climate systems, with unique biodiversity, and a long and complex history of Hominin occupation. Yet many islands have no published palaeoenvironmental/palaeoclimatic archives, leaving their natural histories to be inferred from broad, regional climate interpretations. This thesis evaluates the records that do exist, their geographic and temporal extents and resolutions. A meta analysis of all existing records in AM shows a paucity of archives from Wallaceae—especially terrestrial records—compared with surrounding areas; temporal sample resolution decreases steeply with time; annually resolved records extend to only ~11,000 years ago; and the purported variability of the Holocene may be an artefact of sampling bias. To address this, the thesis sets out to analyse archives on the large islands of Timor and Seram. A 3 m pollen record from lake Nefona in Timor Barat was radiocarbon dated to ~2000 yr BP. It suggests a past, fluctuating between closed Syzygium rainforest and open Eucalypt savanna, interacting with fire and possibly influenced by human activity. Seven speleothems from Seram and one from Timor were analysed, adding two localities in the region to just eight published previously. Floating chronologies based on annual lamina were anchored using a series of 20 conventional U/Th dates, U/Th using laser ablation, 22 radiocarbon dates, and the 14C bomb pulse. Speleothems were dated to brief windows from MIS 4 through to the modern. Stable isotope and lamina growth rate analyses of these speleothems were conducted at annual resolution, providing insights into the hydrology of the region at times when no other annual resolution records were previously available. CS-μXRF was conducted on specimens, yielding trace elemental analyses as subannual resolution, allowing interpretation of the IASM during the last glacial, deglacial, and Holocene. The one specimen from Timor suggested conditions approximately 2600 years ago were similar to today, but with regular peaks in rainfall every 10–15 years, possibly due to a confluence between ENSO and IOD. Specimens from Seram reveal a complex relationship with the regional climate systems, including a change from year round rainfall (as it is today) to significantly seasonal rainfall, likely driven by the IASM, during somewhat drier times. Further, the apparent driest times in these records, around 10 and 64 ka, appear to have no seasonal pattern. That is, the Seram seems to have a monsoonal climate pattern when it is not very wet (as it is today) nor very dry. This monsoonal “sweet spot” seems to have existed during the last glacial in Seram except in the driest extremes when the IASM may have been entirely inactive
Bismuth-NSAIDs as colorectal cancer chemopreventives
No full textAustralia has one of the highest incidence rates of colorectal cancer globally. The overexpression of cyclooxygenase-2 (COX-2), an enzyme involved in the inflammatory response, has been linked to several cancer types, including colorectal cancer. COX-2 impacts numerous downstream molecular pathways, leading to several advantageous traits that promote the growth of cancer cells. Consequently, chronic inflammation is a risk factor that has been linked to the development of colorectal cancer. Non-steroidal anti-inflammatory drugs (NSAIDs) inhibit COX-2 and numerous animal, epidemiological, and clinical studies have demonstrated that that the long-term administration of NSAIDs can prevent the development (i.e., act as chemopreventive agents) of colorectal cancer. Unfortunately, NSAIDs also inhibit COX-1, whereby the prolonged, daily administration of NSAIDs has been linked to numerous gastrointestinal (GI) side effects, such as ulceration and bleeding. Bismuth is a group 15 post-transition metal that is used in many common formulations for the treatment of GI ailments, including dyspepsia, and gastric and duodenal ulcers. Consequently, it is hypothesised that the combination of NSAIDs and bismuth in a single compound, a BiNSAID complex, could allow for the chemopreventive actions of the NSAID while combatting the associated GI side-effects. The aim of this Thesis was to investigate the potential of a series of BiNSAIDs of the general formula [Bi(L3)] (where L = tolfenamate (tolf), mefenamate (mef), indomethacin (indo) or aspirinate (asp)) as chemopreventives for colorectal cancer and compare this to the free NSAIDs, tolfH, mefH, indoH, and aspH. This was done at a fundamental level, investigating the interactions with lipid membrane mimics, at an in vitro level, where the cellular effects were explored, and finally in vivo, using a chemically induced mouse model of colorectal cancer
Understanding the transition of Registered Nurses moving into forensic mental health employment
No full textBackground: The nursing profession faces significant challenges in building and maintaining a skilled workforce to meet the escalating healthcare demand. Factors such as population health trends, an aging nursing workforce, and poor retention rates contribute to increasing health needs and nursing shortages. Forensic mental health, which represents the interface between law and mental health, functions in diverse community settings. Registered nurses in inpatient forensic mental health settings are responsible for providing comprehensive nursing care and treatment while navigating the complexities of criminal justice processes. Heightened security and management of potentially violent patients with complex backgrounds create specific workforce challenges for any nurse employed in the setting. Given the multifaceted challenges and the growth of forensic mental health services, organisations must support and retain nurses in this clinical area. Compared to research on new graduate nurses, there is limited attention to the transition of registered nurses into different areas, including forensic mental health. Understanding their transition experiences is crucial for ensuring local workforce systems adequately support these nurses. Aim: This Doctoral study sought to explore the transition of registered nurses into forensic mental health employment. Methods: This sequential explanatory mixed-methods study commenced with a cross-sectional online survey of registered nurses working in an inpatient forensic mental health hospital. Semi-structured interviews with a subgroup of survey respondents were subsequently undertaken. The survey collected demographic data, reasons for choosing forensic mental health employment and experiences of their commencement of employment, induction, satisfaction, and interpersonal challenges during the transition. Validated tools, the Revised Professional Practice Environment Scale and the Nurse Retention Index were included. Descriptive statistics summarised demographic information, and independent sample t-tests were used with the validated tools. Semi-structured interviews, guided by survey findings and nursing transition literature, were undertaken face-to-face, recorded, and transcribed verbatim. Data analysis employed Braun and Clarke's1 six-step thematic analysis approach. Findings: The online survey achieved a 51.1% (n=69) response rate. Over half of the respondents (n=37, 53.6%) acquired their nursing qualifications overseas. The survey emphasised the importance of pre-existing interest in forensic mental health and encouragement from hospital staff as influential factors in job-seeking. During their first year of transition, respondents encountered feelings of isolation, a lack of support, and anxiety while providing patient care. Regarding the work environment, respondents positively perceived 'internal work motivation' but faced challenges in 'handling disagreement and conflict'. While many expressed an intent to continue their nursing careers, almost half (n=29, 45.3%) were undecided about leaving the forensic mental health setting. Eleven participants were interviewed. The initial phase of their transition presented obstacles, including adapting to new knowledge, changes in clinical responsibilities, exposure to patients' background offences, and security processes. Interpersonal challenges were also experienced. This included navigating inconsistent clinical practices, managing professional and personal groups, and seeking support from management. Despite these initial difficulties, participants discovered opportunities for authentic engagement with patients during their transition. Conclusion: The multifaceted experiences transitioning into forensic mental health employment emphasise the interconnectedness of professional identity, belongingness, and organisational climate. The pivotal role of workplace belongingness emerged, influencing integration through inclusive relationships and open dialogues. Organisational climate, particularly positive line manager behaviours, significantly impacted well-being during the transition. Addressing leadership challenges and fostering a positive atmosphere can enhance staff satisfaction and transition experiences, establishing supportive environments for a committed nursing workforce in forensic mental health