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Organometallic Lanthanide Bismuth Cluster Single-Molecule Magnets
No full textSingle-molecule magnets (SMMs) are molecules that can retain magnetic polarization in the absence of an external magnetic field and embody the ultimate size limit for spin-based information storage and processing. Multimetallic lanthanide complexes lacking magnetic exchange coupling enable fast relaxation pathways that attenuate the full potential of these species. Employment of diamagnetic heavy main group elements with diffuse orbitals may lead to unprecedented strong coupling. Herein, two bismuth cluster bridged lanthanide complexes, [K(THF)4]2[Cp*2Ln2Bi6] (Cp* = pentamethylcyclopentadienyl; 1-Ln, Ln = Tb, Dy), were synthesized via a solution organometallic approach. The neutral [Ln2Bi6] heterometallocubane core features lanthanide centers that are bridged by a rare Bi66- Zintl ion which supports strong ferromagnetic interactions between lanthanides. This affords the rare observation of magnetic blocking and open hysteresis loops for superexchange-coupled SMMs comprising solely lanthanide ions. Both compounds constitute the first SMMs containing bismuth donors paving the way for promising synthetic targets for quantum computation
Homozygous missense variants in <i>BMPR15 </i>can result in primary ovarian insufficiency
No full textResearch Question: Does a genetic condition underlie the diagnosis of primary ovarian insufficiency (POI) in a 13 year old girl with primary amenorrhea.Design: A case report of next generation sequencing panel of 24 genes associated with syndromal and nonsyndromal POI was conducted.Results: A homozygous missense variant c.1076C>T, p.(Pro359Leu) in BMP15 was identified. Conclusions: The biallelic variant c.1076C >T, p.(Pro359Leu) in BMP15 is associated with primary ovarian failure
LOCAL LIMIT THEOREMS FOR THE RANDOM CONDUCTANCE MODEL AND APPLICATIONS TO THE GINZBURG-LANDAU ∇Ø INTERFACE MODEL
No full textTropoelastin and Elastin Assembly
No full textElastic fibers are an important component of the extracellular matrix, providing stretch, resilience and cell interactivity to a broad range of elastic tissues. Elastin makes up the majority of elastic fibers and is formed by the hierarchical assembly of its monomer, tropoelastin. Our understanding of key aspects of the assembly process have been unclear due to the intrinsic properties of elastin and tropoelastin that render them difficult to study. This review focuses on recent developments that have shaped our current knowledge of elastin assembly through understanding the relationship between tropoelastin’s structure and function
Quantifying the Effects of MV-LV Distribution Network Constraints and DER Reactive Power Capabilities on Aggregators
No full textDistributed energy resources (DER), such as photovoltaic systems and batteries, are becoming common among households. Although the main objective is reducing electricity imports (bills), they could also provide system-level services via an aggregator. However, the more DER provide services, the more important is ensuring that the corresponding operation does not result in network issues. To help DER aggregators understand the implications of network constraints, this work proposes an AC optimal power flow-based methodology to quantify the effects that three-phase low voltage (LV) and medium voltage (MV) network constraints can have on the volume of services that can be provided for a given horizon, and the potential benefits from using DER reactive power capabilities. Using a convex multi-period formulation that avoids binary variables for batteries and incorporates voltage-dependent load models, the methodology maximizes DER exports (services) for service-related periods and household self-consumption for other periods (reducing bills). Different service periods are assessed to explore the extent of services throughout the day. Results using a realistic UK MV-LV network with 2,400+ households, show that aggregator services can be highly overestimated when neglecting MV-LV constraints, these depend on voltage-demand load characteristics, and that exploiting DER reactive power capabilities can significantly unlock further services
Novel pervaporation-assisted pressure swing reactive distillation process for intensified synthesis of dimethyl carbonate
No full textDimethyl carbonate (DMC) is an environmentally friendly agent with low toxicity and fast biodegradability. DMC synthesis by transesterification of propylene carbonate with methanol has been developed as a cost-efficient option. However, even reactive distillation combined with a series of distillation columns requires significant energy and capital cost. To solve these problems, a novel pervaporation-assisted pressure swing reactive distillation process is proposed in this work as an eco-efficient solution for the transesterification synthesis route. Rigorous simulations were carried out in Aspen Plus, using a custom pervaporation model developed in Aspen Custom Modeler (ACM). Pervaporation (PV) is used for the efficient separation of DMC/MeOH azeotrope, and employs polydimethylsiloxane / polyvinylidene fluoride (PDMS/PVDF) composite membrane. The membrane area is optimized to minimize total annual cost (TAC) of the process. Energy integration by Pinch Analysis was also carried out using Aspen Energy Analyzer to determine the optimal heat exchangers network. The results show that the new intensified PSRD-PV process is more competitive compared with the reference reactive distillation (RD) process reported in literature, allowing about 32% energy savings (due to the ability of PV to separate an azeotrope without distillation), around 42% lower annual cost (1.72 M$ yr-1), as well as largely improved sustainability metrics
Light Curve Calculations for Triple Microlensing Systems
No full textWe present a method to compute the magnification of a finite source star lensed by a triplelens system based on the image boundary (contour integration) method. We describe a newprocedure to obtain continuous image boundaries from solutions of the tenth-order polynomial obtained from the lens equation. Contour integration is then applied to calculate the image areas within the image boundaries, which yields the magnification of a source with uniform brightness. We extend the magnification calculation to limb-darkened stars approximated with a linear profile. In principle, this method works for all multiple lens systems, not just triple lenses. We also include an adaptive sampling and interpolation method for calculating densely covered light curves. The C++ source code and a corresponding Python interface are publicly available
Switching Contexts: Transportability Measures for NLP
No full textThis paper explores the topic of transportability, as a sub-area of generalisability. By proposing the utilisation of metrics based on well-established statistics, we are able to estimate the change in performance of NLP models in new contexts. Defining a new measure for transportability may allow for better estimation of NLP system performance in new domains, and is crucial when assessing the performance of NLP systems in new tasks and domains. Through several instances of increasing complexity, we demonstrate how lightweight domain similarity measures can be used as estimators for the transportability in NLP applications. The proposed transportability measures are evaluated in the context of Named Entity Recognition and Natural Language Inference tasks
Neighbourhoods and dementia: An updated realist review of the qualitative literature to inform contemporary practice and policy understanding
No full textThis realist review of the literature provided a contemporary understanding of neighbourhoods and dementia and described how people living with dementia and their neighbourhood interacted via ongoing place-making and remaking processes. Drawing on 44 articles, neighbourhoods were revealed to have fluid and dynamic qualities where people with dementia used their strength and resources to connect to significant people and places. The review also indicated that the person with dementia-neighbourhood relationship was underpinned by four themes: 'home', 'social interactions', 'activities' and 'transportation'. Further research is encouraged to use innovative, participatory methods to explore the neighbourhood-dementia nexus in depth whilst paying close attention to social inclusion and diversity