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Cell-to-cell connectivity assays for the analysis of cytoskeletal and other regulators of plasmodesmata
Get PDFFunding: Z.B. is funded by the UK Biotechnology and Biological Sciences Research Council EASTBIO Doctoral Training Partnership. The Tilsner lab receives funding from the Scottish Government Rural and Environment Science and Analytical Services (RESAS).The actin cytoskeleton has close but so far incompletely understood connections to plasmodesmata, the cell junctions of plants. Plasmodesmata are essential for plant development and responses to biotic and abiotic stresses and facilitate the intercellular exchange of metabolites and hormones but also macromolecules such as proteins and RNAs. The molecular size exclusion limited of plasmodesmata is dynamically regulated, including by actin-associated proteins. Therefore, experimental analysis of plasmodesmal regulation can be relevant to plant cytoskeleton research. This chapter presents two simple imaging-based protocols for analyzing macromolecular cell-to-cell connectivity in leaves
A practical guide to the diagnosis and management of suspected Non-tuberculous Mycobacterial Pulmonary Disease (NTM-PD) in the United Kingdom
Get PDFNon-tuberculous Mycobacterial Pulmonary Disease (NTM-PD) is a chronic disease characterised by progressive inflammatory lung damage due to infection by non-tuberculous mycobacteria (NTM). Global prevalence of NTM-PD is generally low but is rising, likely due to a combination of increased surveillance, increasing multimorbidity and improved diagnostic techniques. Most disease is caused by Mycobacterium avium complex species. NTM-PD can be challenging to both diagnose and manage but given the risk of untreated disease and the challenges around drug treatments, it is vital that all healthcare professionals involved in primary care consider NTM-PD at the earliest opportunity. In particular, NTM-PD should be considered where there are respiratory symptoms in the setting of pre-existing chronic lung disease such as chronic obstructive pulmonary disease (COPD) and bronchiectasis. Early suspicion should lead to appropriate primary screening measures. This article discusses the relevance of NTM-PD today, risk factors for developing disease, pathways from clinical presentation to referral to specialist care, and discusses management and drug treatments. A flow diagram of a screening process is presented as a guideline for best practice from a United Kingdom perspective.Peer reviewe
Investigating the visible phase-curve variability of 55 Cnc e
Get PDFFunding: EMV acknowledges support from the Centre for Space and Habitability (CSH). This work has been carried out within the framework of the National Centre of Competence in Research PlanetS supported by the Swiss National Science Foundation under grants 51NF40_182901 and 51NF40_205606. EMV acknowledges the financial support of the SNSF. B.-O.D. acknowledges support from the Swiss State Secretariat for Education, Research and Innovation (SERI) under contract number MB22.00046. ABr was supported by the SNSA. S.G.S. acknowledges support from FCT through FCT contract no. CEECIND/00826/2018 and POPH/FSE (EC). This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (project SPICE DUNE, grant agreement no. 947634). LBo, VNa, IPa, GPi, RRa, GSc, VSi, and TZi acknowledge support from CHEOPS ASI-INAF agreement no. 2019-29-HH.0. DJB acknowledges financial support from the CSH, University of Bern. ML acknowledges support of the Swiss National Science Foundation under grant number PCEFP2_194576. ASt acknowledges support from the PLATO/CNES grant at CEA/IRFU/DAp and the French Programme National de Planétologie (PNP). This work was supported by FCT - Fundação para a Ciência e a Tecnologia through national funds and by FEDER through COMPETE2020 - Programa Operacional Competitividade e Internacionalizacão by these grants: UID/FIS/04434/2019, UIDB/04434/2020, UIDP/04434/2020, PTDC/FIS-AST/32113/2017 & POCI-01-0145-FEDER-032113, PTDC/FIS-AST/28953/2017 & POCI-01-0145-FEDER-028953, PTDC/FIS-AST/28987/2017 & POCI-01-0145-FEDER-028987, O.D.S.D. is supported in the form of work contract (DL 57/2016/CP1364/CT0004) funded by national funds through FCT. YAl acknowledges the support of the Swiss National Fund under grant 200020_172746. We acknowledge support from the Spanish Ministry of Science and Innovation and the European Regional Development Fund through grants ESP2016-80435-C2-1-R, ESP2016-80435-C2-2-R, PGC2018-098153-B-C33, PGC2018-098153-B-C31, ESP2017-87676-C5-1-R, MDM-2017-0737 Unidad de Excelencia Maria de Maeztu-Centro de Astrobiología (INTA-CSIC), as well as the support of the Generalitat de Catalunya/CERCA programme. The MOC activities have been supported by the ESA contract no. 4000124370. S.C.C.B. acknowledges support from FCT through FCT contracts nr. IF/01312/2014/CP1215/CT0004. X.B., S.C., D.G., M.F. and J.L. acknowledge their role as ESA-appointed CHEOPS science team members. ACC acknowledges support from STFC consolidated grant numbers ST/R000824/1 and ST/V000861/1, and UKSA grant number ST/R003203/1. This project was supported by the CNES. L.D. is an F.R.S.-FNRS Postdoctoral Researcher. This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (project FOUR ACES. grant agreement no. 724427). DE acknowledges financial support from the Swiss National Science Foundation for project 200021_200726. M.F. and C.M.P. gratefully acknowledge the support of the Swedish National Space Agency (DNR 65/19, 174/18). DG gratefully acknowledges financial support from the CRT foundation under grant no. 2018.2323 “Gaseous or rocky? Unveiling the nature of small worlds”. S.H. gratefully acknowledges CNES funding through the grant 837319. P.M. acknowledges support from STFC research grant number ST/M001040/1. This work was also partially supported by a grant from the Simons Foundation (PI Queloz, grant number 327127). IRI acknowledges support from the Spanish Ministry of Science and Innovation and the European Regional Development Fund through grant PGC2018-098153-B-C33, as well as the support of the Generalitat de Catalunya/CERCA programme. GyMSz acknowledges the support of the Hungarian National Research, Development and Innovation Office (NKFIH) grant K-125015, a PRODEX Experiment Agreement No. 4000137122, the Lendület LP2018-7/2021 grant of the Hungarian Academy of Science and the support of the city of Szombathely. V.V.G. is an F.R.S.-FNRS Research Associate. N.A.W. acknowledges UKSA grant ST/R004838/1. A.C.C. and T.W. acknowledge support from STFC consolidated grant numbers ST/R000824/1 and ST/V000861/1, and UKSA grant number ST/R003203/1. NCS acknowledges funding by the European Union (ERC, FIERCE, 101052347).Context . 55 Cnc e is an ultra-short period super-Earth transiting a Sun-like star. Previous observations in the optical range detected a time-variable flux modulation that is phased with the planetary orbital period, whose amplitude is too large to be explained by reflected light and thermal emission alone. Aims . The goal of the study is to investigate the origin of the variability and timescale of the phase-curve modulation in 55 Cnc e. To this end, we used the CHaracterising ExOPlanet Satellite (CHEOPS), whose exquisite photometric precision provides an opportunity to characterise minute changes in the phase curve from one orbit to the next. Methods . CHEOPS observed 29 individual visits of 55 Cnc e between March 2020 and February 2022. Based on these observations, we investigated the different processes that could be at the origin of the observed modulation. In particular, we built a toy model to assess whether a circumstellar torus of dust driven by radiation pressure and gravity might match the observed flux variability timescale. Results . We find that the phase-curve amplitude and peak offset of 55 Cnc e do vary between visits. The sublimation timescales of selected dust species reveal that silicates expected in an Earth-like mantle would not survive long enough to explain the observed phase-curve modulation. We find that silicon carbide, quartz, and graphite are plausible candidates for the circumstellar torus composition because their sublimation timescales are long. Conclusions . The extensive CHEOPS observations confirm that the phase-curve amplitude and offset vary in time. We find that dust could provide the grey opacity source required to match the observations. However, the data at hand do not provide evidence that circumstellar material with a variable grain mass per unit area causes the observed variability. Future observations with the James Webb Space Telescope (JWST) promise exciting insights into this iconic super-Earth.Peer reviewe
The role of drag and gravity on dust concentration in a gravitationally unstable disc
Get PDFFunding: SR acknowledges support from a Royal Society Enhancement Award, and (along with RA) funding from the Science & Technology Facilities Council (STFC) through Consolidated Grant ST/W000857/1. FM acknowledges support from the Royal Society Dorothy Hodgkin Fellowship. RN acknowledges support from UKRI/EPSRC through a Stephen Hawking Fellowship (EP/T017287/1). JW acknowledges support from the University of St Andrews. HA acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No 101054502). KR is grateful for support from the UK STFC via grant ST/V000594/1. RAB is supported by a Royal Society University Research Fellowship.We carry out three-dimensional smoothed particle hydrodynamics simulations to study the role of gravitational and drag forces on the concentration of large dust grains (St > 1) in the spiral arms of gravitationally unstable protoplanetary discs, and the resulting implications for planet formation. We find that both drag and gravity play an important role in the evolution of large dust grains. If we include both, grains that would otherwise be partially decoupled will become well coupled and trace the spirals. For the dust grains most influenced by drag (with Stokes numbers near unity), the dust disc quickly becomes gravitationally unstable and rapidly forms clumps with masses between 0.15–6M⊕. A large fraction of clumps are below the threshold where runaway gas accretion can occur. However, if dust self-gravity is neglected, the dust is unable to form clumps, despite still becoming trapped in the gas spirals. When large dust grains are unable to feel either gas gravity or drag, the dust is unable to trace the gas spirals. Hence, full physics is needed to properly simulate dust in gravitationally unstable discs. Dust trapping of large grains in spiral arms of discs stable to gas fragmentation could explain planet formation in very young discs by a population of planetesimals formed due to the combined roles of drag and gravity in the earliest stages of a disc’s evolution. Furthermore, it highlights that gravitationally unstable discs are not just important for forming gas giants quickly, it can also rapidly form Earth mass bodies.Peer reviewe
Radio signatures of star–planet interactions, exoplanets and space weather
Get PDFFunding: BJSP acknowledges funding from the ARC DECRA DE21 scheme and the Big Questions Institute. RDK acknowledges funding from the Dutch Research Council (NWO) for the e-MAPS (exploring magnetism on the planetary scale) project (project number VI.Vidi.203.093) under the NWO talent scheme Vidi. SB acknowledges funding from the Dutch Research Council (NWO) for the ‘Exo-space weather and contemporaneous signatures of star-planet interactions’ of the research programme ‘Open Competition Domain Science- M’ (number OCENW.M.22.215). MD acknowledges support from the INAF funding scheme Fundamental Research in Astrophysics 2022 (mini grant “A pilot study to explore the potential of SRT in detecting nearby radio-emitting stars with confirmed or candidate exoplanets, supported by a radial velocity follow-up”). PZ acknowledges funding from the ERC N◦101020459−Exoradio. SM acknowledges funding from NSF AST-2108512 for a precision NIR M dwarf radial velocity survey with HPF, from NASA XRP investigating radio detected M dwarfs. JM acknowledges funding from the French National Research Agency (ANR) under contract number ANR-18-CE31-0019 (SPlaSH). AAV acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No 817540, ASTROFLOW). GS acknowledges support provided by NASA through the NASA Hubble Fellowship grant HST-HF2-51519.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS5-26555. BK acknowledge funding from the European Research Council under the European Union’s Horizon 2020 research and innovation programme (grant agreement No 865624, GPRV). JDT was supported for this work by NASA through the NASA Hubble Fellowship grant #HST-HF2-51495.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. JS received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 884711). JMG acknowledges support by the “Programme National de Planetologie” (PNP) of CNRS/INSU co-funded by CNES and by the “Programme National de Physique Stellaire” (PNPS) of CNRS/INSU co-funded by CEA and CNES. MMK acknowledges support from the Heising-Simons Foundation through the 51 Pegasi b Fellowship grant 2021-2943.Radio detections of stellar systems provide a window onto stellar magnetic activity and the space weather conditions of extrasolar planets — information that is difficult to obtain at other wavelengths. The maturation of low-frequency radio instruments and the plethora of wide-field radio surveys have driven recent advances in observing auroral emissions from radio-bright low-mass stars and exoplanets. To guide us in putting these recent results in context, we introduce the foremost local analogues for the field: solar bursts and the aurorae found on Jupiter. We detail how radio bursts associated with stellar flares are foundational to the study of stellar coronae, and time-resolved radio dynamic spectra offer one of the best prospects for detecting and characterizing coronal mass ejections from other stars. We highlight the possibility of directly detecting coherent radio emission from exoplanetary magnetospheres, as well as early tentative results. We bridge this discussion with the field of brown dwarf radio emission — the larger and stronger magnetospheres of these stars are amenable to detailed study with current instruments. Bright, coherent radio emission is also predicted from magnetic interactions between stars and close-in planets. We discuss the underlying physics of these interactions and the implications of recent provisional detections for exoplanet characterization. We conclude with an overview of outstanding questions in the theory of stellar, star–planet interaction and exoplanet radio emission and the potential of future facilities to answer them.Peer reviewe
A gray-box attack against latent diffusion model-based image editing by posterior collapse
Get PDFRecent advancements in Latent Diffusion Models (LDMs) have revolutionized image synthesis and manipulation, raising significant concerns about data misappropriation and intellectual property infringement. While adversarial attacks have been extensively explored as a protective measure against such misuse of generative AI, current approaches are severely limited by their heavy reliance on model-specific knowledge and substantial computational costs. Drawing inspiration from the posterior collapse phenomenon observed in VAE training, we propose the Posterior Collapse Attack (PCA), a novel framework for protecting images from unauthorized manipulation. Through comprehensive theoretical analysis and empirical validation, we identify two distinct collapse phenomena during VAE inference: diffusion collapse and concentration collapse. Based on this discovery, we design a unified loss function that can flexibly achieve both types of collapse through parameter adjustment, each corresponding to different protection objectives in preventing image manipulation. Our method significantly reduces dependence on model-specific knowledge by requiring access to only the VAE encoder, which constitutes less than 4% of LDM parameters. Notably, PCA achieves prompt-invariant protection by operating on the VAE encoder before text conditioning occurs, eliminating the need for empty prompt optimization required by existing methods. This minimal requirement enables PCA to maintain adequate transferability across various VAE-based LDM architectures while effectively preventing unauthorized image editing. Extensive experiments show PCA outperforms existing techniques in protection effectiveness, computational efficiency (runtime and VRAM), and generalization across VAE-based LDM variants. Our code is available at https://github.com/ZhongliangGuo/PosteriorCollapseAttack.Peer reviewe
Magnetic topology of the solar corona
Get PDFThis thesis examines the magnetic topology of the solar corona. Many of the dynamic processes in the Sun’s atmosphere are driven by the magnetic field, and so understanding the structure of such such fields is a key step towards modelling these phenomena.
The technique of Magnetic Charge Topology (MOT) is used to determine the topologies due to various source configurations. The balanced four-source case is completely classified, and seven distinct topological states are found. This is compared to the complete three-source classification performed by Brown and Priest (1999a). A method is described for extending the analysis to greater numbers of sources.
MOT is also used to discuss the creation of magnetic null points in the solar corona. Until recently, it was tacitly assumed that any coronal nulls would have to be created by means of a local double-separator bifurcation in the photospheric source plane. A counter-example - the new, coronal local separator bifurcation - with five unbalanced sources is found and analysed, and several seven-source scenarios are also discussed.
We also find that this new bifurcation plays a critical role in the Magnetic Breakout Model for solar flares and coronal mass ejections (Antiochos et al., 1999). We provide a simple MCT model for a flaring delta-spot region and find that a ‘breakout’ can be provoked in several different ways.
Finally, a Monte Carlo variation on MCT is used to determine the proportion of upright nulls in a field due to a large number of sources. By overlaying two plane topologies, we find also the number of separators and use the result to calculate typical sizes for elemental flux loops in the corona
HERITALISE. Project insights and initial developments
Get PDFFunding: This project is funded by the European Union under the Horizon EU research and innovation programm HORIZON-CL2-2023-HERITAGE-ECCCH-01 (A European Collaborative Cloud for Cultural Heritage - 2023) under grant agreement No. 1011580811 HERITALISE).Cultural Heritage (CH) encompasses a broad spectrum of tangible and intangible assets, from artifacts and architecture to landscapes and traditions. These require diverse and complex data for documentation, study, and preservation. Technological advancements have significantly improved how CH is digitised, enhancing understanding and access. Digital records preserve historical, aesthetic, and scientific values while supporting public engagement. However, there remains no universal standard for CH digitisation, with approaches often tailored to each project based on various technical and contextual factors. Digitisation methods depend on object-specific complexity criteria such as size, material and their condition, and location, requiring multidisciplinary collaboration. Common techniques are usually employed like laser scanning, photogrammetry and structured light, while AI and emerging technologies are expanding the capabilities of advancing digitization and visualization. In the present paper the EU HERITALISE project is presented, which addresses current limitations by developing advanced methods for capturing holistically both visible and non-visible CH features. It extends frameworks like H (Holistic)-HBIM to a Memory twin, integrating multimodal and complex data types in four (4) selected demo sites presented in this paper
Constraint models for Klondike
Get PDFFunding: Peter Nightingale: EPSRC grant EP/W001977/1 Felix Ulrich-Oltean: EPSRC grant EP/W001977/1.Klondike is the most famous single-player card game, and remains a challenging search problem even in the “thoughtful” variant where all card locations are known. We consider the full game of Klondike except for one restriction that the unusual move of “worrying back” is disallowed. This model is able to determine the winnability of all instances of the game and in practice does so in less than 2000 secs for 10,000 instances we tested, which no other known algorithm can achieve. On some instances, however, other techniques can produce answers more quickly. We use constraint modelling to produce schedules for running our constraint model in combination with other techniques. The combination outperforms any single solver across a range of time limits. Using this combination we are able to significantly improve the best estimate of winnability of Klondike without worrying back. Finally we show how we can use this work to also improve the estimate of winnability of the regular game of Klondike
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