Tue 27 May 13:00: Computer Vision: Between Forensics and Biomedical Imaging
The seminar will be an interdisciplinary journey between applications of Artificial Intelligence (AI) Computer Vision based methods to the field of Forensics and Biomedical Imaging. I will first focus on AI applications for country recognition and city verification, presenting two works in which AI based models have been applied to such forensics task, with a final overview of other forensics applications such as visual sentiment analysis and detection of generated images through AI methods. Subsequently the seminar will focus on further applications of AI vision methods to the field of deep generative models for Biomedical Imaging, with a particular focus on a work on deep generative model for structural brain MRI reconstruction and interpretation.
- Speaker: Giovanna Maria Dimitri, University of Siena (Italy)
- Tuesday 27 May 2025, 13:00-14:00
- Venue: Lecture Theatre 2, Computer Laboratory, William Gates Building.
- Series: Artificial Intelligence Research Group Talks (Computer Laboratory); organiser: Mateja Jamnik.
Wed 14 May 16:00: Profinite rigidity of Kähler groups
A classical problem in complex algebraic geometry is understanding the topology of closed complex submanifolds of complex projective space, so-called smooth complex projective varieties, and, more generally, of compact Kähler manifolds. Two natural topological invariants to consider are the fundamental group and its profinite completion; the latter is also known as the algebraic fundamental group. In this talk I will address the following questions: When is the fundamental group of a compact Kähler manifold uniquely determined by its profinite completion? And, when does the profinite completion even determine the homeomorphism type of the underlying manifold? In particular, I will explain positive answers to both questions in the case of a direct product of fundamental groups of closed hyperbolic Riemann surfaces. This talk is based on joint work with Hughes, Py, Spitler, Stover and Vidussi.
- Speaker: Claudio Llosa Isenrich (KIT)
- Wednesday 14 May 2025, 16:00-17:00
- Venue: CMS, MR15.
- Series: Differential Geometry and Topology Seminar; organiser: Oscar Randal-Williams.
Tue 13 May 14:00: Harmonic maps to the circle with higher dimensional singular set
We consider the problem of finding harmonic maps to the circle with a prescribed singular set in an arbitrary Riemannian manifold and characterise their uniqueness in terms of the “one-dimensional topology” of the ambient space. We then show how these maps can be used to define new notions of (n-2)-volume, leading to a promising approximation scheme for classical codimension 2 minimal surfaces.
- Speaker: Marco Badran (ETH Zurich)
- Tuesday 13 May 2025, 14:00-15:00
- Venue: MR13.
- Series: Partial Differential Equations seminar; organiser: Giacomo Ageno.
Wed 14 May 14:30: Nanoconfined Superionic Water is Molecular Superionic
Superionic ice, where water molecules dissociate into a lattice of oxygen ions and a rapidly diffusing “gas” of protons, represents an exotic state of matter with broad implications for planetary interiors and energy applications [1,2]. Recently, a nanoconfined superionic state of water has been predicted [3,4], which exists at far milder temperatures than conventional superionic ices and at pressures similar to those created naturally in Van der Waals materials [5]. Interestingly, in sharp contrast to bulk ice, this phase is comprised of intact water molecules. This molecular superionic behaviour has possible applications in a range of electrochemical and electrocatalytic applications. However, at present, we lack the design principles necessary to design other materials with these properties.
In this talk, I will use machine learning and electronic structure simulations to establish how nanoconfined water can be both molecular and superionic. We also explore what insights this material offers for superionic states in general. Similar to bulk superionic ice and other superionic materials [6], nanoconfined water conducts via concerted chain-like proton migrations, which cause the rapid propagation of defects [7]. However, unlike other molecular phases of water, its exceptional conductivity arises from: (i) low barriers to proton transfer; and (ii) a flexible hydrogen-bonded network. We propose that these are two key characteristics of fast ionic conduction in molecular superionics. The insights obtained here establish design principles for the discovery of other molecular superionic materials, with potential applications in energy storage and beyond.
References: 1. Matusalem F et al. (2022) Plastic deformation of superionic water ices. Proc Natl Acad Sci USA119 :e2203397119. https://doi.org/10.1073/pnas.2203397119 2. Cheng B et al. (2021) Phase behaviours of superionic water at planetary conditions. Nat Phys 17(11):1228–1232. https://doi.org/10.1038/s41567-021-01334-9 3. Kapil V et al. (2022) The first-principles phase diagram of monolayer nanoconfined water. Nature 609(7927):512–516. https://doi.org/10.1038/s41586-022-05036-x 4. Ravindra P et al. (2024) Nuclear quantum effects induce superionic proton transport in nanoconfined water. arXivpreprint arXiv:2410.03272. https://arxiv.org/abs/2410.03272 5. Algara-Siller G et al. (2015) Square ice in graphene nanocapillaries. Nature 519(7544):443–445. https://doi.org/10.1038/nature14295 6. Morgan BJ (2021) Mechanistic origin of superionic lithium diffusion in anion-disordered Li₆PS₅X argyrodites. Chem Mater 33(6):2004–2018. https://doi.org/10.1021/acs.chemmater.0c03738 7. Catlow CRA (1990) Atomistic mechanisms of ionic transport in fast-ion conductors. J Chem Soc, Faraday Trans86(8):1167. https://doi.org/10.1039/FT9908601167
- Speaker: Dr Samuel Coles, University of Cambridge
- Wednesday 14 May 2025, 14:30-15:30
- Venue: Unilever Lecture Theatre, Yusuf Hamied Department of Chemistry.
- Series: Theory - Chemistry Research Interest Group; organiser: Lisa Masters.
Tue 13 May 14:00: BSU Seminar: "A Regression Tree Approach to Missing Data" This will be a free hybrid seminar. To register to attend virtually, please click here: https://cam-ac-uk.zoom.us/j/81415700586?pwd=7rhWD5jDWlkAq1nuMUPDJGDkhQsMCM.1
Analysis of data with missing values is arguably the hardest problem in statistics. Statistical methods are often designed for completely observed data and are inapplicable if some values are missing. Although there are many techniques for imputation of missing values, the statistical properties of the resulting fitted models are unknown, except in special situations that require unverifiable and likely unjustifiable assumptions, such as “missing at random” (MAR) and “no unobserved confounding”.
We use a large dataset of electronic health records of Covid-19 patients and a national consumer expenditure survey to show that (1) routine imputation of missing data is inadvisable and even illogical, as missingness itself can contain useful information that imputation destroys and (2) popular imputation algorithms such as MICE are impractical when the amount of missing data is large. We also show how the GUIDE classification and regression tree method easily overcomes these difficulties. GUIDE is unique among tree algorithms in many respects, including its ability to completely avoid imputation of missing data in predictor variables and to explicitly display the effects of missing values in its decision tree diagrams. Literature on GUIDE and its accompanying software may be obtained at https://pages.stat.wisc.edu/~loh/guide.html.
This will be a free hybrid seminar. To register to attend virtually, please click here: https://cam-ac-uk.zoom.us/j/81415700586?pwd=7rhWD5jDWlkAq1nuMUPDJGDkhQsMCM.1
- Speaker: Professor Wei-Yin Loh, Department of Statistics, University of Wisconsin, Madison, USA
- Tuesday 13 May 2025, 14:00-15:00
- Venue: Large Seminar Room, East Forvie Building, Forvie Site Robinson Way Cambridge CB2 0SR..
- Series: MRC Biostatistics Unit Seminars; organiser: Alison Quenault.
Thu 15 May 16:00: From nuclear swelling to chemoattractant production during tissue damage
Abstract not available
- Speaker: Dr Balázs Enyedi - Semmelweis University, Budapest
- Thursday 15 May 2025, 16:00-17:00
- Venue: Hodgkin Huxley Seminar Room, Physiology building, Downing Site CB2 3EG.
- Series: Foster Talks; organiser: foster.
Mon 09 Jun 13:00: Richard Relhan: can a portrait be reconstructed from the biographical bones?
Abstract not available
- Speaker: Chris Preston
- Monday 09 June 2025, 13:00-14:00
- Venue: Seminar Room 1, Department of History and Philosophy of Science.
- Series: Cabinet of Natural History; organiser: .
Thu 08 May 16:00: Potassium channel activators - a possible anti-seizure treatment.
Abstract not available
- Speaker: Prof Frederik Elinder - Linköping University, Sweden
- Thursday 08 May 2025, 16:00-17:00
- Venue: Hodgkin Huxley Seminar Room, Physiology building, Downing Site CB2 3EG.
- Series: Foster Talks; organiser: foster.
Mon 02 Jun 13:00: Planting crops, gathering knowledge: scientific objects, plantation economies and knowledge production in nineteenth-century Guatemala
Abstract not available
- Speaker: Christian Stenz (Heidelberg University)
- Monday 02 June 2025, 13:00-14:00
- Venue: Seminar Room 1, Department of History and Philosophy of Science.
- Series: Cabinet of Natural History; organiser: .
Mon 26 May 13:00: Cave science, bat guano and prehistory in the Malay Peninsula, c. 1900
Abstract not available
- Speaker: Katherine Enright (Faculty of History)
- Monday 26 May 2025, 13:00-14:00
- Venue: Seminar Room 1, Department of History and Philosophy of Science.
- Series: Cabinet of Natural History; organiser: .
Mon 19 May 13:00: Vere, Lady Lynch (1647–1682): women colonists as artists and scientists in early English Jamaica
Abstract not available
- Speaker: Eleanor Stephenson (Faculty of History)
- Monday 19 May 2025, 13:00-14:00
- Venue: Seminar Room 1, Department of History and Philosophy of Science.
- Series: Cabinet of Natural History; organiser: .
Mon 12 May 13:00: 'North to the future': deep ecological fieldwork in Arctic Alaska
Abstract not available
- Speaker: Ben Weissenbach (Scott Polar Research Institute)
- Monday 12 May 2025, 13:00-14:00
- Venue: Seminar Room 1, Department of History and Philosophy of Science.
- Series: Cabinet of Natural History; organiser: .
Radical Scavenger-Driven Oxidation Prevention and Structural Stabilization for Efficient and Stable Tin-Based Perovskite Solar Cells
DOI: 10.1039/D5EE00735F, PaperSeungon Jung, Yunjeong Jang, Hohyun Jung, Yujin Kim, Eunbin Son, Seulgi Jeong, Yihan Zhang, Joohoon Kang, Jeong Min Baik, Jianfeng Lu, Hyesung Park
Tin (Sn)-based perovskite solar cells (PSCs) have emerged as promising alternatives to lead-based PSCs owing to their lower toxicity and desirable optoelectronic properties. However, the instability of Sn-based perovskites and...
The content of this RSS Feed (c) The Royal Society of Chemistry
Reducing Energy Loss by Developing Luminescent Triphenylamine Functionalized Electron Acceptor for High Performance Organic Solar Cells
DOI: 10.1039/D5EE01525A, PaperYue Chen, Xiaopeng Duan, Junjie Zhang, Zhongwei Ge, Haisheng Ma, Xiaobo Sun, Huotian Zhang, Jiaxin Gao, Xuelin Wang, Xunchang Wang, Zheng Tang, Renqiang Yang, Feng Gao, Yanming Sun
The persistent challenge of high non-radiative recombination energy loss (ΔEnr) remains a critical bottleneck in advancing the power conversion efficiency (PCE) of organic solar cells (OSCs). Herein, a fused non-fullerene...
The content of this RSS Feed (c) The Royal Society of Chemistry
Closing the Carbon Cycle: Challenges and Opportunities of CO2 Electrolyser Designs in Light of Cross-Industrial CO2 Source-Sink Matching in the European Landscape
DOI: 10.1039/D4EE06204C, Analysis Open Access   This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.Muhammad Tayyab, Maximiliane Dreis, Dennis Blaudszun, Kevinjeorjios Pellumbi, Urbain Nzotcha, Muhammad Qaiser Masood, Sebastian Stiessel, Henning Weinrich, Hermann Tempel, Kai junge Puring, Ruediger-A. Eichel, Ulf-Peter Apfel
The defossilisation of the chemical industry is a critical milestone in achieving climate-friendly and sustainable production routes. In this regard, CO2-electrolysis technologies have emerged as a foundational element of Carbon...
The content of this RSS Feed (c) The Royal Society of Chemistry
Mon 09 Jun 16:00: Title to be confirmed
Abstract not available
- Speaker: Matthew Hornsey (University of Queensland)
- Monday 09 June 2025, 16:00-17:00
- Venue: Ground Floor Lecture Theatre, Department of Psychology, Downing Site, Cambridge.
- Series: Social Psychology Seminar Series (SPSS); organiser: Yara Kyrychenko.
Conjugated Side‐Chains Optimize Giant Acceptor Compatibility with Low‐Cost Polymer Donor to Overcome the Cost‐Efficiency‐Stability Trilemma in Polymer Solar Cells
High-efficiency and stable polymer solar cells typically rely on expensive oligomeric small-molecule acceptors and high-cost polymer donors. To overcome this limitation, conjugated side chains are strategically employed to modulate and dimerize acceptors, precisely tuning their thermodynamic properties for optimal compatibility with the low-cost polymer donor PTQ10. This approach provides a viable pathway toward sustainable and renewable energy solutions.
Abstract
Polymer solar cells (PSCs) rely on blends of small-molecule acceptors (SMAs) and polymer donors, but the thermodynamic relaxation of SMAs requires an oligomeric approach to enhance operational stability. However, high-efficiency devices often depend on the expensive synthesis of oligomeric SMAs and costly polymer donors, posing a significant barrier to achieving sustainable and renewable energy. Here, the challenge is addressed through a thermodynamically derived compatibility of giant acceptors with the low-cost polymer donor PTQ10. This is achieved by strategically employing conjugated side chains to modulate and dimerize acceptors, thereby precisely tuning their thermodynamic properties to optimize compatibility. Our synthetic route avoids toxic reagents, halogenated solvents, and harsh conditions. The dimer (DYBT) incorporating an n-type linker enhances crystallinity, absorption, and intramolecular superexchange coupling compared to its p-type counterpart, and achieves a device efficiency of 19.53%. Considering efficiency, stability, and material cost, the potential cost per kilowatt for the PTQ10:DYBT device is 0.10 $ kW−1, while most systems exceed 10 $ kW−1. These findings offer valuable insights for the cost-effective oligomeric acceptors, to well pair with low-cost donors and reduce the overall material cost of the photo-active layer for sustainable and durable energy.
Natural van der Waals Canalization Lens for Non‐Destructive Nanoelectronic Circuit Imaging and Inspection
Canalization-based super-resolution imaging has been achieved based on ultralow-loss and extremely anisotropic phonon polaritons in a natural van der Waals material α-MoO3. This canalization lens exhibits the superior capability to resolve deeply subwavelength feature sizes down to 15 nm, which represents a promising solution for non-destructive nanoelectronic circuit imaging and inspection.
Abstract
Optical inspection has long served as a cornerstone non-destructive method in semiconductor wafer manufacturing, particularly for surface and defect analysis. However, conventional techniques such as dark-field scattering optics or atomic force microscopy (AFM) face significant limitations, including insufficient resolution or the inability to resolve subsurface features. Here, an approach is proposed that integrates the strengths of dark-field scattering optics and AFM by leveraging a van der Waals (vdW) canalization lens based on natural biaxial α-MoO3 crystals. This method enables ultrahigh-resolution subwavelength imaging with the ability to visualize both surface and buried structures, achieving a spatial resolution of 15 nm and grating pitch detection down to 100 nm. The underlying mechanism relies on the unique anisotropic properties of α-MoO3, where its atomic-scale unit cells and biaxial symmetry facilitate the diffraction-free propagation of both evanescent and propagating waves via a flat-band canalization regime. Unlike metamaterial-based superlenses and hyperlenses, which suffer from high plasmonic losses, fabrication imperfections, and uniaxial constraints, α-MoO3 provides robust and super-resolution imaging in multiple directions. The approach is successfully applied to achieve high-resolution inspection of buried nanoscale electronic circuits, offering unprecedented capabilities essential for next-generation semiconductor manufacturing.
Mon 02 Jun 14:00: Title to be confirmed
Abstract not available
- Speaker: Miles H. Wheeler (University of Bath)
- Monday 02 June 2025, 14:00-15:00
- Venue: MR13.
- Series: Partial Differential Equations seminar; organiser: Giacomo Ageno.
Mon 09 Jun 14:00: Title to be confirmed
Abstract not available
- Speaker: Tobias Barker (University of Bath)
- Monday 09 June 2025, 14:00-15:00
- Venue: MR13.
- Series: Partial Differential Equations seminar; organiser: Giacomo Ageno.