32151 research outputs found
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Immobilized nucleoside 2-deoxyribosyltransferases from extremophiles for nucleoside biocatalysis
Get PDFFunding: C.M.C. and P.T. are funded by the Wellcome trust (217078/Z/19/Z). S.A.H.M. is funded by Consejo Nacional de Humanidades Ciencia y Tecnologı́a (CONAHCYT) Mexico (486638) and by the Global Challenges Research Fund (GCRF) grant GCRFNGR4\1388. R.P.S. and E.M.M.M. are funded by the project, Development of Smart Edible Coating for the Preservation of Berries I025-IAMSM005-C3-T1-T, of the Challenge-Based Research Funding Program of the Tecnologico de Monterrey.The synthesis of nucleosides is crucial for pharmaceutical and biotechnological applications, acting as drugs and as essential building blocks for numerous therapeutic agents. However, most enzymes employed in nucleoside biocatalysis are not recycled, possess limited stability, and have strict substrate selection for ribonucleosides or 2′deoxyribonucleosides. We employed 2′-deoxyribonucleoside transferase (NDT) enzymes from thermophilic and psychrophilic bacteria to demonstrate they can be immobilized to enhance specific activity, stability, and recyclability. NDT enzymes from Chroococcidiopsis thermalis (CtNDT), and Bacillus psychrosaccharolyticus (BpNDT) were immobilized by covalent attachment to chitosan beads. A double mutant of CtNDT, capable of generating 3′deoxyribonucleosides, showed remarkable and increased stability after immobilization compared to the same enzyme in the solution. Furthermore, we demonstrated the recyclability of immobilized biocatalysts, with a 10-fold improvement in reaction yield over 20 consecutive cycles, highlighting the practicality and sustainability of the developed immobilization method. We used our strategy to produce a pharmaceutically relevant 3′deoxyribonucleoside (2-fluoro-3′-deoxyadenosine). This highlights the importance of efficient immobilization techniques to enhance the catalytic properties of NDT enzymes, expanding their utility in biocatalysis.Peer reviewe
Computational exploration of stereoelectronic relationships in manganese‐catalysed hydrogenation reactions
Get PDFFunding: The authors thank EaStCHEM and the School of Chemistry for support through the EaSI-CAT centre for Doctoral Training (ASG).Stereoelectronic effects governing Mn-catalyzed hydrogenation reactions have been deconvoluted through the analysis of a series of in silico catalyst modifications using DFT (PBE0-D3PCM(EtOH)/def2-TZVP//RI-BP86PCM(EtOH)/def2-SVP level of theory). Computations were performed on the Mn-catalyzed reduction of indanone based on a catalyst from the Clarke group, consisting of a tridentate ligand with pyridine, amine, and phosphine donors and a ferrocenyl linker in the backbone. Enantioselectivity enhancements were found through two pathways; first, with the stabilization of aromatic substrates by means of an extended π-system, enhancing π-stacking noncovalent interactions; second, by the introduction of steric bulk around the active site to destabilize one of the diastereomeric hydride transfer transition states. Electronic effects were differentiated from sterics by modification of the phenyl groups at the phosphine, trans- to the metal-hydride bond. While electron-withdrawing groups increased the thermodynamic driving force, the highest activity is predicted with electron-donating groups due to the improved basicity of the nitrogen lone pair, required for the initiation of hydrogen activation. Based on these observations, promising routes for synthetic catalyst design may involve donating groups which improve activity, coupled with enantiodiscrimination via steric bulk as a more general strategy than being limited to π-containing substrates.Peer reviewe
Recognizing perceived interdependence in face-to-face negotiations through multimodal analysis of nonverbal behavior
Get PDFFunding: This research was (partially) funded by the Hybrid Intelligence Center, a 10-year programme funded by the Dutch Ministry of Education, Culture and Science through the Netherlands Organisation for Scientific Research, https://hybrid-intelligence-centre.nl, grant number 024.004.022 and the MINGLE project number 639.022.606. Data collection was funded by an ERC Starting Grant (#635356) awarded to Daniel Balliet.Enabling computer-based applications to display intelligent behavior in complex social settings requires them to relate to important aspects of how humans experience and understand such situations. One crucial driver of peoples' social behavior during an interaction is the interdependence they perceive, i.e., how the outcome of an interaction is determined by their own and others' actions. According to psychological studies, both the nonverbal behavior displayed by Motivated by this, we present a series of experiments to automatically recognize interdependence perceptions in dyadic face-to-face negotiations using these sources. Concretely, our approach draws on a combination of features describing individuals' Facial, Upper Body, and Vocal Behavior with state-of-the-art algorithms for multivariate time series classification. Our findings demonstrate that differences in some types of interdependence perceptions can be detected through the automatic analysis of nonverbal behaviors. We discuss implications for developing socially intelligent systems and opportunities for future research
Vulnerability of marine megafauna to global at‐sea anthropogenic threats
Get PDFFunding: Pew Charitable Trusts; Jock Clough Marine Foundation; C.F. & E.A. Jenkins Postgraduate Scholarship; Australian Research Council. Grant Number: DP210103091.Marine megafauna species are affected by a wide range of anthropogenic threats. To evaluate the risk of such threats, species’ vulnerability to each threat must first be determined. We build on the existing threats classification scheme and ranking system of the International Union for Conservation of Nature (IUCN) Red List of Threatened Species by assessing the vulnerability of 256 marine megafauna species to 23 at-sea threats. The threats we considered included individual fishing gear types, climate-change-related subthreats not previously assessed, and threats associated with coastal impacts and maritime disturbances. Our ratings resulted in 70 species having high vulnerability (v > 0.778 out of 1) to at least 1 threat, primarily drifting longlines, temperature extremes, or fixed gear. These 3 threats were also considered to have the most severe effects (i.e., steepest population declines). Overall, temperature extremes and plastics and other solid waste were rated as affecting the largest proportion of populations. Penguins, pinnipeds, and polar bears had the highest vulnerability to temperature extremes. Bony fishes had the highest vulnerability to drifting longlines and plastics and other solid waste; pelagic cetaceans to 4 maritime disturbance threats; elasmobranchs to 5 fishing threats; and flying birds to drifting longlines and 2 maritime disturbance threats. Sirenians and turtles had the highest vulnerability to at least one threat from all 4 categories. Despite not necessarily having severe effects for most taxonomic groups, temperature extremes were rated among the top threats for all taxa except bony fishes. The vulnerability scores we provide are an important first step in estimating the risk of threats to marine megafauna. Importantly, they help differentiate scope from severity, which is key to identifying threats that should be prioritized for mitigation.Peer reviewe
One-dimensional heterocyclic carbene–Au metal–organic frameworks bridging ultra-high vacuum models and scalable liquid-phase growth
Get PDFFunding: The authors acknowledge financial support under the National Recovery and Resilience Plan (NRRP), Mission 4, Component 2, Investment 1.1, by the Italian Ministry of University and Research (MUR), funded by the European Union – NextGenerationEU– Project Title “Microscopic approach to Understand Synergies in Electrocatalysis” - Project No. 2022E5L4Y2 - CUP: C53D23003780006. We acknowledge support from Project C2 chemical complexity (CUP: C93C22009260001) under the MUR program “Dipartimenti di Eccellenza 2023-2027”. Financial support was provided by the US Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES), Materials Sciences and Engineering Division under contract DE-AC02-05-CH11231 (Nanomachine program KC1203) (STM imaging) and contract DE-SC0023105 (molecular design and synthesis). The University of Padova is acknowledged for financial support through the grant #01BIRD2022-UNIPD (MUSYCA) and joint call in education and research 2024 University of Padova and University of St. Andrews “Surface Synthesized Carbene Networks for Electrocatalysis”.We acknowledge financial support under the National Recovery and Resilience Plan (NRRP), Mission 4, Component 2, Investment 1.1, by the Italian Ministry of University and Research (MUR), funded by the European Union – NextGenerationEU– Project Title “Microscopic approach to Understand Synergies in Electrocatalysis” - Project No. 2022E5L4Y2 - CUP: C53D23003780006. We acknowledge support from Project C2 chemical complexity (CUP: C93C22009260001) under the MUR program “Dipartimenti di Eccellenza 2023-2027”. Financial support was provided by the US Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES), Materials Sciences and Engineering Division under contract DE-AC02-05-CH11231 (Nanomachine program KC1203) (STM imaging) and contract DE-SC0023105 (molecular design and synthesis). The University of Padova is acknowledged for financial support through the grant #01BIRD2022-UNIPD (MUSYCA) and joint call in education and research 2024 University of Padova and University of St. Andrews “Surface Synthesized Carbene Networks for Electrocatalysis”.The controlled design of molecule–metal interfaces is central to the development of functional nanomaterials for catalysis, sensing, and molecular electronics. Here we show that the adsorption of a Janus-type diimidazolium precursor on gold yields one-dimensional (1D) N-heterocyclic carbene (NHC)–Au–NHC metal organic frameworks (MOFs) featuring positively charged gold nodes. Using synchrotron X-ray photoemission spectroscopy (XPS), near edge X-ray adsorption fine structure (NEXAFS) spectroscopy and scanning tunnelling microscopy (STM), we demonstrate that thermal activation promotes counterion removal and drives the formation of extended 1D arrays, characterized by ∼1.0 nm Au–Au spacing and adatom densities up to 0.6 atom nm−2 (∼4% of surface atoms). Importantly, we translate this ultra-high vacuum (UHV) benchmark into a scalable solution-phase protocol in ethanol, enabling 1D-MOF growth under mild, base-free, open-air conditions. The resulting films retain structural and electronic signatures of UHV-grown systems, bridging model studies and practical synthesis. This approach establishes NHC–metal frameworks as accessible, tunable platforms for catalysis and materials design.Peer reviewe
Do large language models have a planning theory of mind? : Evidence from MindGames: a multi-step persuasion task
Get PDFTo appear in COLM, 2025Recent evidence suggests Large Language Models (LLMs) display Theory of Mind (ToM) abilities. Most ToM experiments place participants in a spectatorial role, wherein they predict and interpret other agents' behavior. However, human ToM also contributes to dynamically planning action and strategically intervening on others' mental states. We present MindGames: a novel `planning theory of mind' (PToM) task which requires agents to infer an interlocutor's beliefs and desires to persuade them to alter their behavior. Unlike previous evaluations, we explicitly evaluate use cases of ToM. We find that humans significantly outperform o1-preview (an LLM) at our PToM task (11% higher; ). We hypothesize this is because humans have an implicit causal model of other agents (e.g., they know, as our task requires, to ask about people's preferences). In contrast, o1-preview outperforms humans in a baseline condition which requires a similar amount of planning but minimal mental state inferences (e.g., o1-preview is better than humans at planning when already given someone's preferences). These results suggest a significant gap between human-like social reasoning and LLM abilities
TOI-7166 b : a habitable zone mini-Neptune planet around a nearby low-mass star
Get PDFFunding: Funding for KB was provided by the European Union (ERC AdG SUBSTELLAR, GA 101054354). Author FJP acknowledges financial support from the Severo Ochoa grant CEX2021-001131-S funded by MCIN/AEI/10.13039/501100011033 and Ministerio de Ciencia e Innovación through the project PID2022-137241NB-C43. This material is based upon work supported by the National Aeronautics and Space Administration under agreement no. 80NSSC21K0593 for the programme “Alien Earths”. GD acknowledges funding from Magdalen College, Oxford. This work is supported by a grant from the Simons Foundation (PI Queloz, grant no. 327127). JdW and MIT gratefully acknowledge financial support from the Heising-Simons Foundation. This work is supported by the Swiss National Science Foundation (PP00P2-163967, PP00P2-190080, and the National Centre for Competence in Research PlanetS). This work has received fund from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement no. 803193/BEBOP), from the MERAC foundation, and from the Science and Technology Facilities Council (STFC; grant no. ST/S00193X/1). KAC acknowledges support from the TESS mission via subaward s3449 from MIT. JdW and MIT gratefully acknowledge financial support from the Heising-Simons Foundation. YGMC has been partially supported by UNAM-PAPIIT-IG101224.We present the discovery and validation of TOI-7166 b, a 2.01 ± 0.05 R⊕ planet orbiting a nearby low-mass star. We validated the planet by combining Transiting Exoplanet Survey Satellite and multicolour high-precision photometric observations from ground-based telescopes, together with spectroscopic data, high-contrast imaging, archival images, and statistical arguments. The host star is an M4-type dwarf at a distance of ∼35 pc from the Sun. It has a mass and a radius of M* = 0.190 ± 0.004 M☉ and R* = 0.222 ± 0.005 R☉, respectively. TOI-7166 b has an orbital period of 12.9 d, which places it close to the inner edge of the Habitable Zone of its host star, receiving an insolation flux of Sp = 1.07 ± 0.08 S⊕ and an equilibrium temperature of Teq = 249 ± 5 K (assuming a null Bond albedo). The brightness of the host star makes TOI-7166 a suitable target for radial velocity follow-up to measure the planetary mass and bulk density. Moreover, the physical parameters of the system including the infrared brightness (Kmag = 10.6) of the star and the planet-to-star radius ratio (0.0823 ± 0.0012) make TOI-7166 b an exquisite target for transmission spectroscopic observations with the James Webb Space Telescope, to constrain the exoplanet atmospheric compositions.Peer reviewe
Subduction origin of the Nb anomaly in Earth's oldest continents
Get PDFFunding: S.L was funded by a Leverhulme Research Project Grant awarded to A.R.H (ICASE) RPG-2019-282. A.R.H was funded by NERC grant NE/X001334/1.Earth is unique in the solar system in having plate tectonics, which controls the growth of life-sustaining continents and the habitability of our planet. The oldest preserved continental crust comprises Eoarchaean (4.0–3.6 Ga) tonalite-trondhjemite (ETT) granitoids that formed through partial melting of thick Hadean (4.5–4.0 Ga) basaltic crust. However, the tectonic processes responsible for generating the earliest continental crust remain controversial. Partial melting of the thick basaltic crust may have occurred in primitive plate tectonic-like subduction zones at depths >45 km. Alternatively, ETT could have been formed at shallower, intracrustal depths 60 km in subduction-like environments, and that some form of primitive plate tectonics must have operated as early as the Eoarchaean.Peer reviewe
How do stock returns respond to a currency devaluation announcement?
Get PDFThis study investigates how the Egyptian stock market responded to the 2024 devaluation of the Egyptian Pound (EGP) and evaluates whether price adjustments reflect semi-strong form market efficiency. Using daily data for EGX30 firms, we estimate abnormal returns around the devaluation announcement and document largely insignificant market-wide reactions, indicating weak evidence of semi-strong efficiency. However, notable cross-firm heterogeneity emerges export-oriented and foreign-revenue-generating firms showed greater resilience, while companies dependent on imported inputs experienced sharper declines. These findings highlight how differences in currency exposure shape firms’ sensitivity to exchange rate shocks in emerging markets with recent dual-rate dynamics. From a practical perspective, the results emphasise the importance of transparent policy communication during major currency adjustments and underline the need for investors to account for firms’ FX risk profiles when constructing portfolios in devaluation-prone environments. The findings also offer insights for regulators seeking to strengthen disclosure practices and improve informational efficiency in the Egyptian capital market.Peer reviewe
Can AI be friends? : An innovative approach to integrating Generative AI as a critical friend in Bahrain Polytechnic's English foundation programme
Get PDFThis practitioner article investigates the innovative implementation of Generative Artificial Intelligence (GAI) as a critical friend in a foundation-level English course at Bahrain Polytechnic. The research explores the use of GAI tools (e.g., ChatGPT, Gemini) over four weeks to enhance students' learning experience, aiming to balance the benefits of GAI with concerns about academic integrity and plagiarism in Higher Education (HE). In this intervention, 17 participants used GAI during class activities, receiving real-time feedback and tailored support, and data collection involved unstructured, non-participant observations of GAI interactions and learners’ reflections submitted via Padlet. Thematic analysis of data revealed changes in classroom dynamics, with quieter classrooms and decreased student-student and student-teacher interactions. The results also highlight that while students initially took longer to complete tasks using GAI, they adapted and became more autonomous over time. The study provides implications for educators on the responsible use of GAI, aiming to reduce the stigma associated with it and promote its ethical integration in HE settings, particularly in teaching English for Academic Purposes (EAP).Peer reviewe
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