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Physics-based solubility prediction for organic molecules
Get PDFFunding: D.J.F., J.W.C., and D.S.P. thank the EPSRC for funding via Prosperity Partnership EP/S035990/1. B.C. thanks EaSI-CAT for funding.Accurate prediction of aqueous solubility for organic molecules is of great importance across a range of fields, from the design and manufacturing of energy materials, to assessing the environmental impact of potential pollutants. It is of particular significance to the pharmaceutical industry, in which problems with low aqueous solubility frequently hamper the development of new drugs. Experimental measurements of solubility are used extensively, but are often time-consuming, resource intensive and only applicable to already synthesized molecules. As such, there is a need for the development of computational approaches to predict solubility. In recent years, there have been considerable advances in physics-based methods, with several contrasting techniques able to give accurate predictions of solubility and a wealth of thermodynamic data for structural optimization. Here, we provide the reader with a thorough understanding of the theoretical background and practical applications of these physics-based methods to predict solubility. This includes discussions of the various advantages and disadvantages of each approach, and an indication of areas of continuing research. Experimental and data-driven methods to assess solubility are also discussed to provide context.Peer reviewe
The psychology of persuasion in the sectarian Dead Sea Scrolls
No full textPersuasion is a universal phenomenon across cultures, times, and regions. The speakers of the Dead Sea Scrolls shaped their reader’s spiritual, moral, and social lives, often responding to external pressures. This study examines how the Damascus Document (CD), the Community Rule (1QS), and “Some of the Precepts of the Torah” (4QMMT) use persuasive strategies with psychological triggers to reinforce sectarian identity, encourage compliance, and legitimize rulings. While some scholars have relied on Greco-Roman rhetorical handbooks to analyze these texts, this research argues that it is unlikely the speakers used such models. Instead, it employs Robert B. Cialdini’s empirically grounded, cross-culturally tested psychology of persuasion model to study the scrolls. This model includes seven principles – authority, liking, unity, reciprocation, scarcity, consistency, and social proof – and four pre-suasive tools: attractors (e.g., fear, sex), magnetizers (e.g., self-relevance, mystery), associations, and ease (e.g., rhythm, rhyme). The findings highlight that authority is predominantly used, but others contribute to the overall rhetorical force of the scrolls in varying degrees. These scrolls reveal that the speakers are skillful persuaders who establish boundaries (e.g., CD), cultivate insider identity (e.g., 1QS), and assert legal opinions (e.g., 4QMMT). Besides these, the scrolls’ persuasiveness is evident in fostering kinship through endearments, appealing to divine reciprocity, and invoking social pressure through rituals and oaths. Scriptural figures are presented as moral exemplars. Fear is used through curses and legal exclusions, balanced by the limited offer of inclusion. Future research applying Cialdini’s model to the Hebrew Bible and Second Temple literature may uncover psychological underpinnings in the rhetorical strategies. This research presents a new approach to studying the persuasive nature of the scrolls, which can be extended to other sectarian scrolls
Invasive mosquitofish impact a threatened toothcarp through water quality impairment and resource competition
Get PDFFunding: This study was financially supported by the Spanish Ministry of Science, Innovation and Universities (MCIN/AEI/ 10.13039/501100011033) and the European Union (NextGenerationEU/PRTR) through projects PID2019-103936GB-C21, PID2019-103936GB-C22, TED2021-129889B-I00, RED2022-134338-T, and PID2023-146173NB-C21).Invasive non-native species are an important cause of biodiversity loss, particularly in fresh waters. The mosquitofish Gambusia holbrooki are among the world’s worst invasive species: they have caused extirpations of native species and are known to sometimes cause trophic cascades and ecosystem effects. This invasive species is also known to impact threatened fishes such as the Spanish toothcarp (Aphanius iberus), which is endemic to Mediterranean Spain. However, it is unclear if the impact of mosquitofish on many fishes is more through resource competition, agonistic interactions or predation, and how often mosquitofish cause trophic cascades. To clarify these questions, we performed a 48-day mesocosm experiment in eutrophic conditions to test for interspecific effects and clarify the impact mechanism using six treatments: the two fish species alone each at two densities, and the two fish species mixed or separated with a net that prevented direct interactions among them. We observed clear fish treatment effects on several variables. At low initial fish densities, the population growth rate of mosquitofish was orders of magnitude greater than that of the Spanish toothcarp, likely contributing to its invasive success and ecological impact. At high fish densities, turbidity, chlorophyll a concentration and daytime dissolved oxygen percentage increased, whereas total phosphorus decreased; crucially, the trophic cascade caused by mosquitofish was stronger than that by toothcarp. The experiment also demonstrated that the interspecific effects of mosquitofish on toothcarp were more important than those of intraspecific competition. The invasive species produced effects on population growth rate, size structure, and fish condition (mass-length relationship) of toothcarp. Effects on population growth rate of toothcarp seem more caused by resource competition, whereas impacts on size structure and condition seem also caused by more direct interactions. The diversity of effects of mosquitofish underscores the difficulty of predicting the impact of invasive species. Our study further provides an approach to differentiate the effects of resource competition from other more direct ecological interactions and so to clarify the impact mechanism of aquatic invasive species.Peer reviewe
Visible light communication using thermally activated delayed fluorescent OLEDs
Get PDFFunding: The authors are grateful to the Engineering and Physical Sciences Research Council for support through grants EP/R035164/1 and EP/Y037243/1.Thermally activated delayed fluorescent (TADF) materials are appealing due to their ability to make efficient organic light-emitting diodes (OLEDs). In this study, we develop TADF OLEDs for visible light communication (VLC) and show that devices using the TADF emitter 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN) can achieve a data rate of 54 Mbps over a 2 m VLC link. To enhance the bandwidth and data rate, we then developed TADF-sensitized fluorescent (hyperfluorescent) OLEDs. Using the fluorescent material 5,10,15,20-tetraphenylbisbenz[5,6]indeno[1,2,3-cd:1′,2′,3′-lm]perylene (DBP) as the terminal emitter, we achieve a data rate of 102 Mbps, which is much higher than the 10 Mbps reported for a phosphorescent OLED. Our results show that TADF and hyperfluorescent OLEDs are suitable for optical wireless communication, as the delayed fluorescence was found not to limit the data rate. This is particularly relevant for VLC applications requiring higher efficiency than fluorescent OLEDs can provide, such as lighting and displays.Peer reviewe
Music, art, science and the decolonisation of history. Roundtable on Sanjay Seth’s Beyond Reason: Postcolonial Theory and the Social Sciences (2021)
Get PDFTo disseminate the stimulating discussion that took place in May 2023 as part of the Immaterial Festival in Évora, Práticas da História presents the debate from the conference "Music, Art, Science and the Decolonization of History". The session was moderated by Luís Trindade (University of Coimbra) and featured a lecture by historian Sanjay Seth (Goldsmiths College, University of London). Following the lecture, interventions were made by musicologist João Pedro Cachopo (researcher at CESEM / NOVA FCSH – IN2PAST) and art historian Mariana Pinto dos Santos (researcher at IHA / NOVA FCSH – IN2PAST). The public will find a series of reflections that Seth, prompted by Luís Trindade (IHC – NOVA FCSH / IN2PAST), shared based on his book Beyond Reason: Postcolonial Theory and the Social Sciences. His discussion focused on the codes of History and how the discipline can learn from art and music, and vice versa. In his lecture, Seth highlights the various ways of understanding what can be investigated in each respective area, with Cachopo and Santos engaging in dialogue during their interventions. These discussions revolve around conceptions of the past that establish parameters for evaluating time, what is alive or not, and what is part of the present or has potentially ceased to exist.Peer reviewe
X-ray structures of some heterocyclic sulfones
Get PDF1,4-Thiazine S,S-dioxide 1 , the cis- and trans-isomers 2 and 3 of its precursor 2,6-diethoxy-1,4-oxathiane S,S-dioxide and diethyl 2,3-dihydro-1,4-thiazine-3,5-dicarboxylate S,S-dioxide 4 have been fully characterised, both in solution by 1H and 13C NMR, and in the solid state by X-ray diffraction. Simulation has been used to model the unexpectedly complex 1H NMR spectra and arrive at a full assignment of all chemical shifts and coupling constants. The crystal structures of both 1 and 4 which adopt, respectively, boat and half-chair conformations, are dominated by strong NH to O=S hydrogen bonding leading to chains of molecules. In the case of 4 the NMR data point to an equatorial position of the C(2)-ester group in solution while in the crystal this adopts an axial orientation. Compounds 2 and 3 adopt chair conformations both in solution and in the solid state with ring inversion on the NMR timescale leading to unexpected simplification of the spectra in the case of 3 .Peer reviewe
A combined soft x-ray and theoretical investigation discloses the water harvesting behaviour of Mg-MOF-74 at the crystal surface
No full textFunding: The authors acknowledge the European Union-NextGenerationEU under the Italian Ministry of University and Research (MUR), Network 4 Energy Sustainable Transition – NEST project – CUP B53C22004070006 with eCO2 cascade project (CUP B53C22004060006), and the Italian Ministry of University and Research (MUR) for the PRIN project “MOF-MTM: tailoring Metal–Organic Frameworks for the direct Methane To Methanol conversion under mild conditions” number 2022SFC459.Metal–organic frameworks (MOFs) are receiving growing interest as transformative materials for real-world atmospheric water harvesting applications. However, obtaining molecular-level details on how surface effects regulate MOF water uptake has proven to be elusive. Here, we present a novel methodology based on ambient pressure soft X-ray absorption spectroscopy (AP-NEXAFS), machine learning-assisted theoretical spectroscopy and molecular dynamics simulations to gain selective insights into the behaviour of water at a MOF crystal surface. We applied our interdisciplinary method to investigate the structural and dynamical properties of water at the surface of the Mg-MOF-74 system, while obtaining complementary information on the water uptake and release from the bulk by synchrotron powder X-ray diffraction. Our investigation pointed out the simultaneous presence of Mg open sites and residual gas-phase water during dehydration, and proved that during water release a high number of surface Mg sites still interact with one or two water molecules. Conversely, when looking at the bulk, a significantly lower number of Mg sites have been found to interact with water molecules in the same experimental conditions. This behaviour suggests that the water adsorption (desorption) process starts from the interior of the material and propagates towards the channel openings. The combined approach based on AP-NEXAFS, PXRD experimental determinations and ML-supported theoretical analyses has been found to be a valuable tool to provide a thorough description of the water harvesting process at both surface and bulk of the crystal.Peer reviewe
Growth, working capital and refinancing : the geography of post-pandemic regional financial resilience in UK SMEs
Get PDFFunding: UK Research and Innovation Economic and Social Research Council (ES/W010259/1).Understanding how small firms adapt and adjust financially following exogenous shocks is crucial and acts as a harbinger of regional financial resilience levels. Therefore, it is important to determine what shape firms are in as they emerge from a shock such as the Covid-19 pandemic, particularly with regard to their ability to finance new growth enhancing activities. Yet not all firms are ready to invest in future growth and simply need an injection of working capital while others need recourse to refinancing existing debts. To flesh out the concept of regional financial resilience, this paper examines how SMEs across different multi-scaler geographies (i.e. regions, sub-regions and districts) of the UK have been raising new loans to finance growth, working capital and/or simply refinancing their existing debt. Using a rich loan dataset for the UK covering 2021 to 2024 we find stark spatial variations in the proportion of firms reporting growth as the key mechanism for using the loans and these are strongest at the most disaggregate unit of spatial analysis examined (i.e. districts). Our findings suggest the future development of the UK economy is likely to display a very uneven spatial pattern with some areas investing heavily in growth, while for others, addressing cash flow problems or issues associated with existing debts are paramount. In response to the pandemic, small firms are exhibiting a complex spatial patchwork of regional financial resilience across the UK’s deeply variegated space economy.Peer reviewe
habtools : an R package to calculate 3D metrics for surfaces and objects
Get PDFFunding: NSFGEO-NERC. Grant Number: 1948946.1. Technological advances in three imaging techniques have opened the door to advanced morphological analyses and habitat mapping for biologists and ecologists. 2. At the same time, the challenge of translating complex 3D data into meaningful metrics that can be used in conjunction with biological data currently hinders progress and accessibility. 3. We introduce habtools, an R package that provides R functions to efficiently calculate complexity and shape metrics from DEMs, 3D meshes and 2D shapes as well as some helper functions to facilitate workflow. 4. We expect the functionality of habtools to continue to expand as new metrics and faster methods become available, and we welcome new contributions and ideas.Peer reviewe
Estimating full-field displacement in biological images using deep learning
Get PDFFunding: PW acknowledges the support of the Research Fellowship from the Royal Commission for the Exhibition of 1851.The estimation of full-field displacement between biological images or in videos is important for quantitative analyses of motion, dynamics and biophysics. However, the often-weak signals, poor contrast and a multitude of noise processes typical to microscopy make this a formidable challenge for many contemporary methods. Here, we present a deep-learning method, termed Displacement Estimation FOR Microscopy (DEFORM-Net), that outperforms traditional digital image correlation and optical flow methods, as well as recent learned approaches, offering simultaneous high accuracy, spatial sampling and speed. DEFORM-Net is experimentally unsupervised, relying on displacement simulation based on a random fractal Perlin-noise process and optimised training loss functions, without experimental ground truths. We demonstrate DEFORM-Net on real biological videos of beating neonatal mouse cardiomyocytes and pulsed contractions in Drosophila pupae, and in various microscopy modalities. We provide DEFORM-Net as open source, including inference in the ImageJ/FIJI platform, to empower new quantitative applications in biology and medicine.Peer reviewe
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