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Covalent organic frameworks have emerged as a thriving family in the realm of photocatalysis recently, yet with concerns about their high exciton dissociation energy and sluggish charge transfer. Herein, a strategy to enhance the built-in electric field of series β-keto-enamine-based covalent organic frameworks by ionic polarization method is proposed. The ionic polarization is achieved through a distinctive post-synthetic quaternization reaction which can endow the covalent organic frameworks with separated charge centers comprising cationic skeleton and iodide counter-anions. The stronger built-in electric field generated between their cationic framework and iodide anions promotes charge transfer and exciton dissociation efficiency. Moreover, the introduced iodide anions not only serve as reaction centers with lowered H* formation energy barrier, but also act as electron extractant suppressing the recombination of electron-hole pairs. Therefore, the photocatalytic performance of the covalent organic frameworks shows notable improvement, among which the CH 3 I-TpPa-1 can deliver an high H 2 production rate up to 9.21 mmol g −1 h −1 without any co-catalysts, representing a 42-fold increase compared to TpPa-1, being comparable to or possibly exceeding the current covalent organic framework photocatalysts with the addition of Pt co-catalysts. Covalent organic frameworks (COFs) show great promise in photocatalysis but are limited by slow charge transfer. Here, the authors report a strategy to enhance the built-in electric field of COFs via ionic polarization, resulting in a hydrogen evolution rate of 9.21 mmol g - ¹ h - ¹ without Pt co-catalysts.

Photocatalytic water disinfection technology is highly promising in off-grid areas due to abundant year-round solar irradiance. However, the practical use of powdered photocatalysts is impeded by limited recovery and inefficient inactivation of stress-resistant bacteria in oligotrophic surface water. Here we prepare a floatable monolithic photocatalyst with ZIF-8-NH 2 loaded Ag single atoms and nanoparticles (Ag SA+NP /ZIF). Atomically dispersed Ag sites form an Ag−N charge bridge, extending the lifetime of charge carriers and thereby promoting reactive oxygen species (ROS) generation. The photothermal effect of the plasmonic Ag nanoparticles reduces the bacterial resistance to ROS and impairs DNA repair capabilities. Under sunlight irradiation, the synergistic effect of Ag single atoms and nanoparticles enables 4.0 cm 2 Ag SA+NP /ZIF to achieve over 6.0 log inactivation (99.9999%) for the stress-resistant Escherichia coli ( E. coli ) in oligotrophic surface water within 30 min. Furthermore, 36 cm 2 Ag SA+NP /ZIF is capable of disinfecting at least 10.0 L of surface water, which meets the World Health Organization (WHO) recommended daily per capita drinking water allocation (8.0 L). This study presents a decentralized and sustainable approach for water disinfection in off-grid areas. Photocatalytic water disinfection holds great promise for off-grid areas due to abundant year-round solar irradiance. Here, authors present a floatable monolithic photocatalyst with ZIF-8-NH 2 loaded Ag single atoms and nanoparticles for efficient and synergistic solar-driven water disinfection.

The unique properties of nanomaterials offer vast opportunities to advance sustainable processes. Incidental nanoparticles (INPs) represent a significant part of nanomaterials, yet their potential for sustainable applications remains largely untapped. Herein, we developed a simple strategy to harness INPs to upgrade the waste-to-resource paradigm, significantly reducing the energy consumption and greenhouse gas emissions. Using the recycling of fly ash from municipal solid waste incineration (MSWI) as a proof of concept, we reveal that incidental iron oxide nanoclusters confined inside the residual carbon trigger Fenton-like catalysis by contacting H 2 O 2 at circumneutral pH (5.0–7.0). This approach efficiently detoxifies the adsorbed dioxins under ambient conditions, which otherwise relies on energy-intensive thermal methods in the developed recovery paradigms. Collective evidence underlines that the uniform distribution of iron oxide nanoclusters within dioxin-enriched nanopores enhances the collision between the generated active oxidants and dioxins, resulting in a substantially higher detoxification efficiency than the Fe(II)-induced bulk Fenton reaction. Efficient and cost-effective detoxification of MSWI fly ash at 278‒288 K at pilot scale, combined with the satisfactory removal of adsorbed chemicals in other solid wastes unlocks the great potential of incidental nanoparticles in upgrading the process of solid waste utilization and other sustainable applications. Detoxification of dioxins is critical for fly ash upcycling but has long been relying on energy-intensive methods. Here, the authors report a simple yet effective paradigm that leverages the Fenton-like activity of the incidental iron oxide nanoclusters to detoxify fly ash under ambient conditions.

Unified visual perception requires integration of bottom-up and top-down inputs in the primary visual cortex (V1), yet the organization of top-down inputs in V1 remains unclear. Here, we used optogenetics-assisted circuit mapping to identify how multiple top-down inputs from higher-order cortical and thalamic areas engage V1 excitatory and inhibitory neurons. Top-down inputs overlap in superficial layers yet segregate in deep layers. Inputs from the medial secondary visual cortex (V2M) and anterior cingulate cortex (ACA) converge on L6 Pyrs, whereas ventrolateral orbitofrontal cortex (ORBvl) and lateral posterior thalamic nucleus (LP) inputs are processed in parallel in Pyr-type-specific subnetworks (Pyr ←ORBvl and Pyr ←LP ) and drive mutual inhibition between them via local interneurons. Our study deepens understanding of the top-down modulation mechanisms of visual processing and establishes that V2M and ACA inputs in L6 employ integrated processing distinct from the parallel processing of LP and ORBvl inputs in L5. The organization of top-down inputs in primary visual cortex (V1) remains unclear. Here the authors characterized corticocortical and thalamocortical top-down inputs recruiting V1 neurons with cell-type and layer-specificities, and revealed distinct forms of top-down input processing.

Acetylation contributes to the bioactivity of numerous medicinally important natural products. However, little is known about the acetylation on sugar moieties. Here we report a saponin acetyltransferase from Astragalus membranaceus . AmAT7-3 is discovered through a stepwise gene mining approach and characterized as the xylose C3′/C4′- O -acetyltransferse of astragaloside IV ( 1 ). To elucidate its catalytic mechanism, complex crystal structures of AmAT7-3/ 1 and AmAT7-3 A310G / 1 are obtained, which reveal a large active pocket decided by a specific sequence AADAG. Combining with QM/MM computation, the regiospecificity of AmAT7-3 is determined by sugar positioning modulated by surrounding amino acids including #A310 and #L290. Furthermore, a small mutant library is built using semi-rational design, where variants A310G and A310W are found to catalyze specific C3′- O and C4′- O acetylation, respectively. AmAT7-3 and its variants are also employed to acetylate other bioactive saponins. This work expands the understanding of saponin acetyltransferases, and provide efficient catalytic tools for saponin acetylation. Currently little is known about the acetylation on sugar moieties. Here the authors report a saponin acetyltransferase from Astragalus membranaceus , AmAT7-3, and utilise crystal structures and QM/MM computation to elucidate the catalytic mechanism: they generate mutants for specific site acetylation.

•Functional connectivity (FC) analysis has been widely applied in clinical populations.•Intrinsic FC networks are found in virtually all brains.•FC suggests that disorders and diseases are less ‘focal’ than previously believed.•Widespread FC changes are found in non-communicative patients.•Challenging barriers must be overcome to enable further clinical applications. Functional connectivity (FC), or the statistical interdependence of blood-oxygen dependent level (BOLD) signals between brain regions using fMRI, has emerged as a widely used tool for probing functional abnormalities in clinical populations due to the promise of the approach across conceptual, technical, and practical levels. With an already vast and steadily accumulating neuroimaging literature on neurodevelopmental, psychiatric, and neurological diseases and disorders in which FC is a primary measure, we aim here to provide a high-level synthesis of major concepts that have arisen from FC findings in a manner that cuts across different clinical conditions and sheds light on overarching principles. We highlight that FC has allowed us to discover the ubiquity of intrinsic functional networks across virtually all brains and clarify typical patterns of neurodevelopment over the lifespan. This understanding of typical FC maturation with age has provided important benchmarks against which to evaluate divergent maturation in early life and degeneration in late life. This in turn has led to the important insight that many clinical conditions are associated with complex, distributed, network-level changes in the brain, as opposed to solely focal abnormalities. We further emphasize the important role that FC studies have played in supporting a dimensional approach to studying transdiagnostic clinical symptoms and in enhancing the multimodal characterization and prediction of the trajectory of symptom progression across conditions. We highlight the unprecedented opportunity offered by FC to probe functional abnormalities in clinical conditions where brain function could not be easily studied otherwise, such as in disorders of consciousness. Lastly, we suggest high priority areas for future research and acknowledge critical barriers associated with the use of FC methods, particularly those related to artifact removal, data denoising and feasibility in clinical contexts.

Reservoir operation is an important and effective measure for realizing optimal allocation of water resources. It can effectively alleviate regional scarcity of water resources, flood disasters and other social problems, and plays an important role in supporting sustainable strategic development of water resources. Coordinating the stakeholders is key to the smooth operation of a multifunctional reservoir. This research examines the competition among stakeholders of a multi-objective ecological reservoir operation aiming to provide for economic, social and ecological demands. A multi-objective game theory model (MOGM) specified 10-day water discharge to meet the triple water demands (power generation, socio-economic consumption and environment) for multi-purpose reservoir operation. The optimal operation of the Three Gorges Reservoir (TGR), with the ecological objective of providing comprehensive ecological flow demanded for some key ecological problems that may occur in the middle and lower reaches of the Yangtze River, was chosen as a case study. Discharged water calculated by the MOGM and a conventional multi-objective evolutionary algorithm/decomposition with a differential evolution operator was then allocated to different demands. The results illustrate the applicability and efficiency of the MOGM in balancing transboundary water conflicts in multi-objective reservoir operation that can provide guidance for the operation of the TGR.

Barcode, including one-dimensional (1D) barcode and two-dimensional (2D) barcode, can be seen almost anywhere in our lives. In many barcode-based mobile systems, different barcodes will appear simultaneously with different angles, shapes, and image quality. Barcode localization is a significant prerequisite for barcode decoding in these applications. In this paper, we propose a region-based end-to-end network to finely localize and classify 1D barcode and Quick Response (QR) code in complex environments. Two special layers are designed in our network. One is a quadrilateral regression layer to localize arbitrary quadrilateral bounding boxes, and another is a Multi-scale Spatial Pyramid Pooling (MSPP) layer to improve the detection accuracy of small-scale barcodes. Extensive experiments on existing public datasets and our own dataset have verified the effectiveness of proposed layers. We also demonstrate that our method can resist some distortions by simulating barcode images of different image qualities. What’s more, a human decoding experiment is also performed to prove the effectiveness of our method as a preprocessor for QR code decoding.

Background The receptors of Notch family play an important role in controlling the development, differentiation, and function of multiple cell types. The aim of this study is to investigate the role of Notch1 signaling upon immune suppression induced by melanoma cells. Methods Melanoma cell line B16 cells were transfected by lentivirus containing mouse Notch1 gene or Notch1 shRNA to generate B16 cell line that highly or lowly expressed Notch1. Notch1 in anti-tumor immune response was comprehensively appraised in murine B16 melanoma tumor model in immunocompetent and immunodeficient mice. The ratios of CD3 + CD8 + cytotoxic T cells, CD49b + NK cells, CD4 + CD25 + FoxP3 + Tregs and Gr1 + CD11b + MDSCs in tumor-DLN or spleen were examined by flow cytometry. After the co-culture of B16 cells and CD8 + T cells, the effects of Notch1 on the proliferation and activation of T cells were assessed by CCK8 assay, CFSE dilution and Chromium-release test. The mRNA expression and supernatant secretion of immunosuppressive cytokines, TGF-β1, VEGF, IL-10 and IFN-γ were measured by RT-PCR and ELISA, respectively. Results Downregulation or overexpression of Notch1 in B16 melanoma cells inhibited or promoted tumor growth in immunocompetent mice, respectively. Notch1 expression in B16 melanoma cells inhibited the infiltration of CD8+ cytotoxic T lymphocytes and NK cells and reduced IFN-γ release in tumor tissue. It could also enhance B16 cell-mediated inhibition of T cell proliferation and activation, and upregulate PD-1 expression on CD4 + and CD8 + T cells. The percentage of CD4 + CD25 + FoxP3 + Tregs and Gr1 + CD11b + MDSCs were significantly increased in tumor microenvironment, and all these were attributed to the upregulation of TGF-β1. Conclusion These findings suggested that Notch1 signaling in B16 melanoma cells might inhibit antitumor immunity by upregulation of TGF-β1.

Large-scale intrinsic brain systems have been identified for exteroceptive senses (such as sight, hearing and touch). We introduce an analogous system for representing sensations from within the body, called interoception, and demonstrate its relation to regulating peripheral systems in the body, called allostasis. Employing the recently introduced Embodied Predictive Interoception Coding (EPIC) model, we used tract-tracing studies of macaque monkeys, followed by two intrinsic functional magnetic resonance imaging samples ( N  = 280 and N  = 270) to evaluate the existence of an intrinsic allostatic–interoceptive system in the human brain. Another sample ( N  = 41) allowed us to evaluate the convergent validity of the hypothesized allostatic–interoceptive system by showing that individuals with stronger connectivity between system hubs performed better on an implicit index of interoceptive ability related to autonomic fluctuations. Implications include insights for the brain’s functional architecture, dissolving the artificial boundary between mind and body, and unifying mental and physical illness. Kleckner et al. use monkey and human data to identify an intrinsic brain system that supports interoception (that is, sensations from within the body) and allostasis (that is, the process by which the brain maintains energy regulation in the body).