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Black Carbon in the Marine Atmosphere: Concentration and Mixing State From Coastal to Remote Atlantic Regions
No full textBlack carbon (BC) from maritime emissions plays a critical role by influencing radiation, cloud processes, and atmospheric dynamics in the marine atmosphere. These impacts depend on BC concentration and mixing state with other aerosol components. However, in situ observations of BC over oceans remain scarce, and the influence of the marine environment on the evolution of BC mixing state is not well understood. Here, we present shipborne measurements aboard the research sailing yacht S/Y Eugen Seibold during 10 Atlantic Ocean cruises. The data set spans 1,120 of measurement hours from near-coastal regions to remote ocean areas. In oceanic regions extending from tens to thousands of kilometers offshore, 1-min averaged BC concentrations were typically around 100 ng m−3, suggesting a well-mixed marine background. Despite the relatively small variability in BC mass concentrations, the mixing state of BC exhibits substantial differences between nearshore and remote oceanic regions. High number fractions (>50%) of BC particles without core-shell morphologies, characterized by BC externally attached to non-BC materials, were observed in near-coastal regions and decreased to ∼20% in remote oceanic regions. In ship-impacted regions, small freshly emitted BC particles tend to coagulate with other aerosol particles and forming non-core-shell attached structures, while high relative humidity (RH > 85%) tends to promote the formation of thick coatings. Our results provide new insights into climate-relevant properties and underscore the importance of coagulation and hygroscopic processing for the mixing state of BC in the marine atmosphere
Predicting functional topography of the human visual cortex from cortical anatomy at scale
No full textTopographic organization, whereby neighboring cortical locations encode neighboring features in sensory or cognitive space, is a fundamental principle of brain function. Existing approaches for obtaining individual-specific topographic maps either require resource-intensive functional neuroimaging or, when relying on population atlases, lack precision for individual-level inference. Here, we introduce deepRetinotopy toolbox, a deep learning-based application for predicting the functional topographic organization of human visual cortex from cortical anatomy alone. DeepRetinotopy toolbox produces accurate retinotopic maps across diverse experimental conditions, imaging sites, and scanner types. We demonstrate how predicted maps can be utilized to automatically generate individual-specific visual area boundaries, overcoming common biases in manual annotations. Finally, we applied our method to 11,060 anatomical scans, which allowed us to quantify age-related changes in the functional organization of visual cortex predictable from anatomy alone, underscoring the method’s broad utility for scalable, anatomy-based functional brain mapping
High‐Sensitivity Self‐Powered X‐Ray Detectors Based on Chiral Bismuth Perovskites
No full textLead-free perovskites are emerging as eco-friendly alternatives for X-ray detection, yet achieving high sensitivity, stability, and self-powered operation remains a challenge. Here, we present a 0D chiral organic-inorganic hybrid bismuth perovskite single crystal, (R/S-NEA)4Bi2Cl10 (NEA = (2-naphthyl)ethylamine), that enables a bulk photovoltaic effect (BPVE) for efficient, self-powered X-ray detection. Its unique structure, featuring isolated [Bi2Cl10]4− dimers within a hydrogen-bonded chiral lattice, facilitates asymmetric charge transport, enhancing intrinsic carrier separation. The resulting detector achieves a record sensitivity of 10 200 µC·Gy−1 cm−2 at 1000 V bias and maintains self-powered operation (0 V) with a low detection limit of 510 nGy s−1, outperforming existing bismuth-based perovskite detectors. Notably, these crystals retain structural integrity for over a year in ambient conditions, while the device exhibits stable operation for over 4000 s under continuous X-ray exposure. This work advances chiral perovskite engineering as a powerful strategy for developing next-generation lead-free X-ray detectors with high performance and long-term durability, making them attractive for portable medical imaging and radiation monitoring
Pooling quantitative MRI data: A multi-protocol study of healthy subcortical ageing
No full textQuantitative MRI (qMRI) measures relaxation rates, exchange rates and proton densities that reflect the biophysical properties of tissue and are ideally free from protocol- and scanner-dependence. In practice, qMRI has not yet achieved this level of independence from sequence and hardware choice, and quantitative measurements often differ across sites and acquisition schemes. At the same time pooling data across different sources can be beneficial to statistical power of longitudinal, cross-sectional or case-control studies. Here we investigate how protocol and hardware differences can affect pooling data from difference sources in large ultra high field (UHF) qMRI studies in the context of healthy aging. We combine the openly available ageing UHF qMRI MP2RAGEME-based dataset with two different MPM-based sets of qMRI data. We evaluate how pooling affects age dependence of qMRI parameters and investigate protocol-related biases, with a particular focus on subcortical structures. We focus the analysis, first, on replication and expansion of the reference qMRI dataset on normative aging, second, the examination of the protocol influence on the measured qMRI values, and third, on detecting the protocol effect on the age dependence inferred from the data. We find that the age-related changes for R1, R2* and volume detected by different protocols were of the same order of magnitude supporting the idea that age-related inter-individual variability can be correctly grasped across sites and protocols using qMRI approaches. We further observe larger relative difference across protocols for R1 and volume, while R2* remains more consistent for most regions. We therefore provide assessment of the pooling effects in the ultra-high resolution UHF qMRI data performed over a relatively large participant cohort, comprising data from different sites collected with different quantitative protocols
Continuous audio‐visual sensor monitoring is more effective than human observers for detecting moor macaques
No full textThe number of species threatened with extinction is continuously increasing, underscoring the need for reliable population estimates to develop effective conservation plans. The ability to confirm a species' presence during surveys (i.e., detectability) is central for population estimates. While audio-visual sensors, like camera traps and passive acoustic monitoring (PAM), have emerged as valuable tools for monitoring primates, few studies have systematically compared their detectability, particularly in dense forests with limited visibility and for elusive species. Here, we compared 40-days continuous monitoring with audio-visual sensor (camera traps, N = 19; PAM, N = 7) versus human-based point transects with three survey visits (N = 20) on wild moor macaques (Macaca maura) in two different habitats: forest (N = 10) and open areas (N = 10). Using occupancy models to compare the detection probability (p), we found that camera traps (p = 0.63 ± 0.04) and PAM (p = 0.79 ± 0.08) outperformed point transects (p = 0.33 ± 0.07), regardless of habitat type. After equalizing survey time between methods, we found that detections were greater on point transects in surveys shorter than 1 day, but camera traps and PAM equalized their performance with two survey days (p-value < 0.05). Notably, combining both audio-visual sensors yielded the highest detectability (p = 0.87 ± 0.05). These results highlight the effectiveness of audio-visual sensors and support multi-method approaches for monitoring primates in tropical forests. Overall, this research contributes to designing more effective monitoring protocols for primate species, which are essential for planning conservation strategies
The Underlying Kinetic-Thermodynamic Relationship in Asynchronous Reactions
No full textWhile kinetic-thermodynamic relationships help understand patterns in reactivity and energy responses, strongly asynchronous reactions often present a weak or erratic kinetic-thermodynamic response, often observed as outliers and noise. This undermines its applicability and significance, the interpolative framework no longer being preserved. The standard practice of directly fitting asynchronous reactions conflates reaction phases, which can lead to negative and/or arbitrarily large local gradients, which are to be understood as artefacts rather than evidence of exotic chemical phenomena. We have found that by decoupling the reaction stages, we obtain the meaningful kinetic-thermodynamic response of concerted asynchronous reactions in a way directly comparable to concerted synchronous reactions. The method restores causality in the kinetic-thermodynamic relationship: it recovers the underlying responses and can be used to probe whether a reaction is elementary and synchronous. We rationalise the origin of these spurious, apparent local gradients in terms of the relative energy trends between the main and secondary stages of the reaction. Through computational calculations of representative examples, including 1,2-hydride shifts, a (3+2) ynolate-nitrone cycloaddition and a gold(I) 6-endo-dig cyclisation, we recover well-behaved, physically interpretable kinetic-thermodynamic relationships by isolating phases through constraining key internal coordinates, separating the energy response of interest from the confounding variable secondary processes. This work shows that even highly asynchronous reactions can be analysed, as well as the key practical differences with concerted synchronous reactions, restoring the interpretative power of thermodynamic dependences for such systems. This can serve as a further practical tool to diagnose the synchronicity of a given presumed reaction step experimentally and to extract the relative energetics of the constituent stages
Alphafold 3-guided insights into the Importinβ: Importin7 heterodimer interaction and its binding to histone H1
No full textThe nuclear import of H1 linker histones is facilitated by a heterodimer of the transport receptors Importinβ (Impβ) and Importin7 (Imp7). The interaction between them is mediated by a stretch of C-terminal residues of Imp7 essential also for Imp7 activation by Impβ. An Impβ:Imp7:H1 complex model was predicted by Alphafold3 and validated using cross-linking data, isothermal titration calorimetry, and pull-down experiments, providing robust support for its accuracy. This model positions the H1 globular domain within the central cavity of Imp7. Refinement of this atomic model against a published cryo-electron microscopy (cryo-EM) map demonstrated significantly improved correspondence compared to the earlier interpretation, which placed the H1 globular domain within Impβ. This enhanced structural consistency further substantiates the accuracy of the AI-driven prediction. Moreover, a detailed analysis confirmed the extended C-terminal stretch of Imp7 harboring a nucleoporin-like binding (NlB) region with two FXFG-like nucleoporin motifs interacting with the outer surface of Impβ
Packing Order Control in Conductive Metal–Organic Frameworks by Tuning Ligand Oxidation State
No full textConductive metal–organic frameworks (c-MOFs), composed of metal nodes and redox-active ligands, have attracted growing interest due to the coexistence of porosity and charge transport. Notably, their electrical performance is closely related to the packing and ligand oxidation state within the framework, which has rarely been explored. Typical divalent metal nodes favor saturated intralayer square-planar coordination to ligands in a single oxidation state, thereby predetermining the framework topology. Here, we report a packing and topology control strategy, achieved by tuning the ligand oxidation state and grounded in lanthanides (e.g., Gd) versatile coordination chemistry. Diffuse reflectance spectroscopy and single-crystal transport measurements reveal that, at low temperature, coordination of Gd3+ with 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP) in a lower mixed oxidation state (−4 and −5) yields a more ordered porous packing (Gd1.5HHTP) with superior electronic transport performance. In contrast, at elevated temperature, the ligand adopts a higher oxidation state (−3), and coordination with Gd3+ yields a densely packed structure with local coordination disorder (GdHHTP), resulting in a markedly reduced electrical conductivity. This study demonstrates ligand-oxidation-state tuning provides an effective strategy for the precise control of structural order and charge transport in c-MOFs, laying a theoretical foundation for the rational design of materials with tunable electronic properties
