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• Speaker: Muriel Dresen, Department of Veterinary Medicine
• Friday 02 May 2025, 08:45-10:00
• Venue: LT2.
• Series: Friday Morning Seminars, Dept of Veterinary Medicine; organiser: Fiona Roby.

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‘To Report or Not to Report: is that the Question?’ Exploring Young People's Reporting Practices of Illicit Drug Ads on Social Media

Better algorithms mean less illegal content on social media. To improve these algorithms, users need to report such content, yet they often do not. This talk will explore young people’s attitudes and practices around reporting a specific online harm: illicit drug advertisements.

A survey of UK students (13–18) examined their reporting practices and tested different messages to encourage reporting. Surprisingly, none were effective, highlighting deeper challenges in the reporting process. This calls into question whether user reporting is the best way to reduce harmful content and highlights the need for a balanced approach that combines proactive detection with user engagement.

• Speaker: Ashly Fuller, University College London
• Friday 14 March 2025, 14:00-15:00
• Venue: Webinar & FW11, Computer Laboratory, William Gates Building..
• Series: Computer Laboratory Security Seminar; organiser: Anna Talas.

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Almost toric yoga for stable double surfaces (Part II)

(This is part II of a series of two talks.)The moduli space of surfaces of general type has a natural compactification where the boundary points correspond to ``stable surfaces’’. If we restrict attention to surfaces which are branched double covers of certain simple surfaces (like the projective plane or a Hirzebruch surface) then singularities can develop in three ways: the branch curve can degenerate, or the base surface can degenerate, or the branch curve and the base surface can develop singularities at the same point. If the limit of the base surface is toric, one can use toric geometry to understand the stable limit of the double cover, but often degenerations of the plane or a Hirzebruch surface are only almost toric (in a precise sense). Thanks to work of Gross, Hacking and Keel, the same diagrammatic techniques that work for toric degenerations can be applied in this setting, and one can use this to get a full classification of normal stable surfaces for some components of the moduli space. I will explain how this works for octic double planes. This is based on joint work with Angelica Simonetti and Giancarlo Urzua.

Please note the unusual time and place.

• Speaker: Jonny Evans (Lancaster)
• Friday 14 March 2025, 10:30-11:30
• Venue: CMS, MR15.
• Series: Differential Geometry and Topology Seminar; organiser: Ailsa Keating.

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Almost toric yoga for stable double surfaces (Part I)

(This is part I of a series of two talks.) The moduli space of surfaces of general type has a natural compactification where the boundary points correspond to ``stable surfaces’’. If we restrict attention to surfaces which are branched double covers of certain simple surfaces (like the projective plane or a Hirzebruch surface) then singularities can develop in three ways: the branch curve can degenerate, or the base surface can degenerate, or the branch curve and the base surface can develop singularities at the same point. If the limit of the base surface is toric, one can use toric geometry to understand the stable limit of the double cover, but often degenerations of the plane or a Hirzebruch surface are only almost toric (in a precise sense). Thanks to work of Gross, Hacking and Keel, the same diagrammatic techniques that work for toric degenerations can be applied in this setting, and one can use this to get a full classification of normal stable surfaces for some components of the moduli space. I will explain how this works for octic double planes. This is based on joint work with Angelica Simonetti and Giancarlo Urzua.

Please note the unusual time and place.

• Speaker: Jonny Evans (Lancaster)
• Thursday 13 March 2025, 11:15-12:15
• Venue: CMS, MR14.
• Series: Differential Geometry and Topology Seminar; organiser: Ailsa Keating.

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Group Testing: Something old, something new, something borrowed

Please note the unusual venue

The problem of group testing entails inferring a subset of defective items from a (much larger) population, using as few ‘pooled tests’ as possible. Each pooled test specifies a subset of the items and produces a binary outcome: ‘negative’ if all the items selected in the test are non-defective, and ‘positive’ otherwise. While the original motivation for group testing was medical testing, it has since found application across a wide variety of scenarios including wireless communications, DNA sequencing, neighbour discovery, and network tomography. We review some of the main results in group testing and then introduce a new variation of the problem (‘cascaded group testing’) where each test is specified by an ordered subset of items, and returns the first defective item in the specified order.

Bio: Nikhil Karamchandani is an Associate Professor with the Department of Electrical Engineering, IIT Bombay. He received the Ph.D. degree from the Department of Electrical and Computer Engineering, University of California at San Diego. He was a postdoctoral scholar with the University of California at Los Angeles and the Information Theory and Applications (ITA) Center, University of California at San Diego. His research interests include networks, information and coding theory, and statistical learning.

• Speaker: Dr Nikhil Karamchandani, IIT Bombay
• Wednesday 26 March 2025, 14:00-15:00
• Venue: MR13, CMS Pavilion E.
• Series: Information Theory Seminar; organiser: Prof. Ramji Venkataramanan.

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Generative models, rare events and tensor networks

I will consider the integration of some ideas and methods from non-equilibrium statistical mechanics and many-body physics with problems in machine learning, specifically so-called diffusion models and reinforcement learning. The focus will be on the optimal realisation of rare events, and on the use of tensor networks to efficiently represent states and dynamical operators. I will also extend some of these ideas to quantum stochastic dynamics, discussing similarities and differences between the classical and quantum cases.

• Speaker: Juan Garrahan (University of Nottingham)
• Thursday 13 March 2025, 14:00-15:30
• Venue: TCM Seminar Room.
• Series: Theory of Condensed Matter; organiser: Gaurav.

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Flexible bioelectronic interfaces with adhesive properties are essential for advancing modern medicine and human-machine interactions. Researchers designed a lithium bond-mediated molecular cascade hydrogel for bioelectronic interfaces, which facilitates robust adhesion at the tissue level and permits atraumatic detachment for repositioning as required. This study presents new insights and potential for advancing bioelectronics and implantable interface technologies.

Abstract

Flexible bioelectronic interfaces with adhesive properties are essential for advancing modern medicine and human-machine interactions. However, achieving both stable adhesion and non-damaging detachment remains a significant challenge. In this study, a lithium bond-mediated molecular cascade hydrogel (LMCH) for bioelectronic interfaces is designed, which facilitates robust adhesion at the tissue level and permits atraumatic detachment for repositioning as required. By integrating the adhesive properties of the molecular cascade structure with the elastic characteristics of the hydrogel interface, the LMCH interface not only achieved a high adhesion strength (197 J m−2) on the skin, but also significantly extended the cracking cycles on the tissue surface during the peeling process from 4 to 380, marking an enhancement of nearly two orders of magnitude. Furthermore, with Young's modulus similar to that of human tissue (25 kPa), exceptional stretchability (1080%), and high ionic conductivity (7.14 S m−1), the LMCH interface demonstrates outstanding tissue compatibility, biocompatibility, and stable detection capabilities for electrocardiogram (ECG) and electromyogram (EMG) signals. This study presents new insights and potential for advancing bioelectronics and implantable interface technologies.

In this work, the C/CoxTy nanoplates with high-efficiency and tunable electromagnetic properties are successfully prepared by customizing Co-based nanoparticles. Relying on these C/CoxTy nanoplates, a series of multispectral electromagnetic functional devices are developed, opening up a new era of multispectral electromagnetic devices.

Abstract

Electromagnetic materials with adjustable dielectric and magnetic properties are constantly sought after in electronic and industrial fields. In this study, an innovative strategy that customizes anchored Co-based nanoparticles to optimize the electronic behaviors is proposed for the first time, enabling a controllable and high-efficiency evolution of the macroscopic electromagnetic response of Co-based (C/CoxTy) nanoplates across the X-ray, light in the solar band and gigahertz band. Specifically, in the gigahertz band, the C/Co and C/Co3Se4 nanoplates with high-power loss capabilities can effectively attenuate and convert electromagnetic energy into heat energy, which not only prevents space electromagnetic radiation but also powers energy for various electromagnetic devices such as thermoelectric generators and microwave actuators. Moreover, multiband antennas and ultra-wideband bandstop filters are successfully achieved and flexibly tuned. Meanwhile, C/CoxTy nanoplates photo- and X-ray detectors are constructed successfully. Additionally, the C/CoTe nanoplate X-ray detector, featuring remarkable stability, sensitivity and penetrability, is successfully utilized to construct the interaction system integrating communication and imaging. In summary, this work offers an effective way for flexible regulation of multispectral electromagnetic response, significantly advancing the development of multispectral electromagnetic functional devices.

Energy Environ. Sci., 2025, Accepted Manuscript
DOI: 10.1039/D5EE00119F, Paper Open Access &nbsp This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence.Jemin Lee, Wonwoo Choi, Eunbin Jang, Hyunjin Kim, Jeeyoung Yoo
Ionic liquid electrolytes (ILEs) provide promising thermal and electrochemical stability characteristics for safer lithium metal batteries (LMBs). However, their development faces challenges due to their low ionic conductivity and poor...
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An innovative strategy is proposed for the atomic-level controllable growth of composition-engineered AlGaN quantum wells (QWs) with residual Al adatom-assisted incorporation-enhanced epitaxy (RAIE) strategy, enabling the achievement of high-efficiency and long-lifetime ultraviolet light-emitting diodes (UV LEDs) with tunable wavelengths spanning the efficiency gap region from 276 to 329 nm in the UV band.

Abstract

AlGaN-based ultraviolet (UV) light-emitting diodes (LEDs) experience a notable reduction in efficiency within the 280–330 nm wavelength range, known as the “UVB gap”. Given the extensive applications of UV LEDs in this wavelength range, it is imperative to bridge this efficiency gap. In this study, a strategy facilitated by the presence of residual Al adatoms is introduced to simultaneously improve the integration of Ga-adatoms and the migration of Al/Ga-adatoms during the growth of low-Al-composition AlGaN quantum wells (QWs) even at high temperatures comparable to those used for high-Al-composition AlGaN quantum barriers. This growth strategy enables the epitaxy of high-quality AlGaN QWs with a wide tunable emission wavelength range across the UVB gap. Utilizing this approach, high-efficiency UV LEDs that effectively bridge the UVB gap are developed. Furthermore, benefiting from this QWs growth configuration, these UV LEDs exhibit an exceptionally long L70 lifetime, marking a significant step forward in the growth technology of AlGaN QWs and expanding the application possibilities of UV LEDs.

This review comprehensively summarizes recent key developments in the field of micro/nanorobots (MNRs) integrated with phototherapy, highlights the critical roles of MNRs-assisted phototherapy in clinical applications, and provides insights into future directions and the pathway toward large-scale clinical implementation.

Abstract

Micro/Nanorobots(MNRs)integrated with phototherapy represent an emerging approach to cancer treatment and hold significant potential for addressing bacterial infections, neurological disorders, cardiovascular diseases, and related conditions. By leveraging micro/nanoscale motor systems in conjunction with phototherapy, these robots enable real-time guidance and monitoring of therapeutic processes, improving drug delivery precision and efficiency. This integration not only enhances the effectiveness of phototherapy but also minimizes damage to surrounding healthy tissues. Nevertheless, clinical translation of MNRs-assisted phototherapy still faces numerous challenges. In this review, recent key developments in the field are comprehensively summarized, the critical roles of MNRs-assisted phototherapy in clinical applications are highlighted, and insights into future directions and the pathway toward large-scale clinical implementation are provided.

The research develops an encapsulation-free, patterned flexible fuel cell patch (PFCP) with the capability to generate electrostimulation with precisely controlled pattern distributions by adjusting electrode configurations. The inherent adhesion and flexibility properties of the PFCP underpin its performance in vivo. The research introduces a novel and promising tool for accelerating tissue repair via the application of patterned electrostimulation.

Abstract

The distribution of electrical potentials and current in exogenous electrostimulation has significant impacts on its effectiveness in promoting tissue repair. However, there is still a lack of a flexible, implantable power source capable of generating customizable patterned electric fields for in situ electrostimulation(electrical stimulation). Herein, this study reports a fuel cell patch (FCP) that can provide in situ electrostimulation and a hypoxic microenvironment to promote tissue repair synergistically. Stable and highly efficient PtNi nanochains and PtNi nanocages electrocatalysts with anti-interference properties catalyze glucose oxidation and oxygen reduction respectively in an encapsulation-free fuel cell. The laser-induced graphene (LIG) electrode loaded with PtNi electrocatalysts is transferred to the surface of a flexible chitosan hydrogel. The resulting flexible FCP can adapt to tissues with different morphologies, firmly adhere to prevent suturing, and provide potent electrostimulation (0.403 V, 51.55 µW cm−2). Additionally, it consumes oxygen in situ to create a hypoxic microenvironment, increasing the expression of hypoxia-inducible factor-1α (HIF-1α). Based on the different pattern requirements of exogenous electrostimulation during the repair of various types of tissue, an axial FCP for peripheral nerves and a flower-patterned FCP for myocardial tissue are constructed and transplanted into animals, showing significant tissue repair in both models.

Rechargeable aqueous batteries with metal anodes promise enhanced energy density, combining higher output voltage and capacity with high safety. This perspective highlights the emerging potential of the Sn metal anode, emphasizing its resistance to hydrogen evolution, high reversibility, and sustainability. Key challenges, including dead Sn formation and electrolyte evolution, as well as innovative design strategies for robust Sn-based batteries are also discussed. The development of Sn metal batteries could contribute to a sustainable society.

Abstract

Rechargeable aqueous batteries based on metallic anodes hold tremendous potential of high energy density enabled by the combination of relatively low working potential and large capacity while retaining the intrinsic safety nature and economical value of aqueous systems; However, the realization of these promised advantages relies on the identification of an ideal metal anode chemistry with all these merits. In this review, the emerging Sn metal anode chemistry is examined as such an anode candidate in both acidic and alkaline media, where the inertness of Sn toward hydrogen evolution, flat low voltage profile, and low polarization make it a unique metal anode for aqueous batteries. From a panoramic viewpoint, the key challenges and detrimental issues of Sn metal batteries are discussed, including dead Sn formation, self-discharge, and electrolyte degradation, as well as strategies for mitigating these issues by constructing robust Sn anodes. New design approaches for more durable and reliable Sn metal batteries are also discussed, with the aim of fully realizing the potential of Sn anode chemistry.

The introduction of P into a single-atom Fe catalyst is shown to induce a shift in its electronic configuration toward a high spin state. This is proposed to enhance electron back donation via the d xz/d yz-π* bond, which improves *COOH adsorption and facilitates the electrochemical conversion of CO2 to CO.

Abstract

Tuning transition metal spin states potentially offers a powerful means to control electrocatalyst activity. However, implementing such a strategy in electrochemical CO2 reduction (CO2R) is challenging since rational design rules have yet to be elucidated. Here we show how the addition of P dopants to a ferromagnetic element (Fe, Co, and Ni) single-atom catalyst (SAC) can shift its spin state. For instance, with Fe SAC, P dopants enable a switch from low spin state (d x2- y2 0, d z2 0, d xz 2, d yz 1, d xy 2) in Fe-N4 to high spin state (d x2-y2 0, d xz 1, d yz 1, d z2 1, d xy 2) in Fe-N3-P. This is studied using a suite of characterization efforts, including X-ray absorption spectroscopy (XAS), electron spin resonance (ESR) spectroscopy, and superconducting quantum interference device (SQUID) measurements. When used for CO2R, the SAC with Fe-N3-P active sites yields > 90% Faradaic efficiency to CO over a wide potential window of ≈530 mV and a maximum CO partial current density of ≈600 mA cm−2. Density functional theory calculations reveal that high spin state Fe3+ exhibits enhanced electron back donation via the d xz/d yz-π* bond, which enhances *COOH adsorption and promotes CO formation. Taken together, the results show how the SAC spin state can be intentionally tuned to boost CO2R performance.

This review focuses on the recent advances and regulation strategies in the 2e⁻ ORR and is systematically structured into three main sections: 1) the latest progress of 2e− ORR in different reaction environments, especially in the acidic and neutral media; 2) microenvironmental modulation, and 3) the coupling system with cathodic 2e− ORR and other anodic reactions. This review aims to shed light on the exploration of efficient catalysts for 2e– ORR and systems for building a green energy roadmap.

Abstract

Electrosynthesis of hydrogen peroxide (H2O2) via two-electron oxygen reduction reaction (2e− ORR) is a promising alternative to the anthraquinone oxidation process. To improve the overall energy efficiency and economic viability of this catalytic process, one pathway is to develop advanced catalysts to decrease the overpotential at the cathode, and the other is to couple 2e− ORR with certain anodic reactions to decrease the full cell voltage while producing valuable chemicals on both electrodes. The catalytic performance of a 2e− ORR catalyst depends not only on the material itself but also on the environmental factors. Developing promising electrocatalysts with high 2e− ORR selectivity and activity is a prerequisite for efficient H2O2 electrosynthesis, while coupling appropriate anodic reactions with 2e− ORR would further enhance the overall reaction efficiency. Considering this, here a comprehensive review is presented on the latest progress of the state-of-the-art catalysts of 2e− ORR in different media, the microenvironmental modulation mechanisms beyond catalyst design, as well as electrocatalytic system coupling 2e− ORR with various anodic oxidation reactions. This review also presents new insights regarding the existing challenges and opportunities within this rapidly advancing field, along with viewpoints on the future development of H2O2 electrosynthesis and the construction of green energy roadmaps.

Magneto-ferroelectric effects in van der Waals EuO/graphene heterostructures emerge via a topotactic method, inducing high compressive strain. This strain stabilizes a ferroelectric state up to room temperature, coexisting with the magnetic proximity effect in graphene. These intertwined magneto-electric effects enable control of magnetization and polarization, offering the potential for next-gen memory and neuromorphic devices.

Abstract

2D van der Waals materials and their heterostructures are a fantastic playground to explore emergent phenomena arising from electronic quantum hybridization effects. In the last decade, the spin-dependant hybridization effect pushed this frontier further introducing the magnetic proximity effect as a promising tool for spintronic applications. Here the uncharted proximity-controlled magnetoelectric effect in EuO/graphene heterostructure is unveiled. This is obtained while creating a new multiferroic hybrid heterostructure with multifunctional properties. Using a topotactic method magnetic insulating EuO thin films on graphene is grown under high compressive strain, which induces the appearance of an additional ferroelectric order, with an electric polarization that reaches up to 18 µC cm−2 at room temperature. This observation therefore quantitatively confirms the theoretical predictions made 15 years ago of a strain-induced ferroelectric state in EuO. Moreover, the EuO induces a magnetic proximity state into the graphene layer by interfacial hybridization. This new ferroelectric state in the EuO/graphene heterostructure is stable up to room temperature where it coexists with the EuO/graphene magnetic state. Furthermore, intertwined magneto-electric effects are shown in these strained heterostructures which can facilitate the manipulation of magnetization and electric polarization in future memory and neuromorphic devices.

Energy Environ. Sci., 2025, Accepted Manuscript
DOI: 10.1039/D4EE04861J, PaperXintong Li, guanzhen chen, Yan Liu, Ruihu Lu, Chao Ma, Ziyun Wang, Yunhu Han, Dingsheng Wang
Precisely regulating the electron transfer capacity and Ru-O covalency of RuO2-based catalysts is crucial and challenging for resolving the inadequate performance of RuO2-based acidic oxygen evolution reaction (OER) catalysts in...
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Nature Materials, Published online: 13 March 2025; doi:10.1038/s41563-025-02182-1

An inhalable nanoplatform responds to inflamed lung tissues by self-assembling into catalytically active fibrillar structures that locally decrease reactive oxygen species, relieve inflammation and alleviate viral pneumonia symptoms.

Nature Energy, Published online: 13 March 2025; doi:10.1038/s41560-025-01742-8

The performance of inorganic, wide-bandgap perovskite solar cells is hindered by unsuitable electron transport layers. Han et al. design an acidic magnesium-doped tin oxide quantum dot layer, improving efficiency and stability in single-junction and tandem cells.

Nature Nanotechnology, Published online: 13 March 2025; doi:10.1038/s41565-025-01874-8

Networking remote superconducting quantum computers requires low-noise microwave-to-optical photon conversion. A transducer based on an integrated silicon electro-optomechanical resonator now achieves below one photon of added noise referred to the transducer input while operating continuously under laser drive.