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Covalent organic frameworks with designable periodic skeletons and ordered nanopores have attracted increasing attention as promising cathode materials for rechargeable batteries. However, the reported cathodes are plagued by limited capacity and unsatisfying rate performance. Here we report a honeycomb-like nitrogen-rich covalent organic framework with multiple carbonyls. The sodium storage ability of pyrazines and carbonyls and the up-to twelve sodium-ion redox chemistry mechanism for each repetitive unit have been demonstrated by in/ex-situ Fourier transform infrared spectra and density functional theory calculations. The insoluble electrode exhibits a remarkably high specific capacity of 452.0 mAh g −1 , excellent cycling stability (~96% capacity retention after 1000 cycles) and high rate performance (134.3 mAh g −1 at 10.0 A g −1 ). Furthermore, a pouch-type battery is assembled, displaying the gravimetric and volumetric energy density of 101.1 Wh kg −1 cell and 78.5 Wh L −1 cell , respectively, indicating potentially practical applications of conjugated polymers in rechargeable batteries. Covalent organic frameworks are receiving increasing attention as promising cathode materials for rechargeable batteries. Here the authors report a honeycomb-like nitrogen-rich COF design in which the pyrazines and carbonyls enable favorable redox chemistry and remarkable Na-ion storage performance.

The materials discovery process can be significantly expedited and simplified if we can learn effectively from available knowledge and data. In the present contribution, we show that efficient and accurate prediction of a diverse set of properties of material systems is possible by employing machine (or statistical) learning methods trained on quantum mechanical computations in combination with the notions of chemical similarity. Using a family of one-dimensional chain systems, we present a general formalism that allows us to discover decision rules that establish a mapping between easily accessible attributes of a system and its properties. It is shown that fingerprints based on either chemo-structural (compositional and configurational information) or the electronic charge density distribution can be used to make ultra-fast, yet accurate, property predictions. Harnessing such learning paradigms extends recent efforts to systematically explore and mine vast chemical spaces and can significantly accelerate the discovery of new application-specific materials.

Layered transition-metal oxides have attracted intensive interest for cathode materials of sodium-ion batteries. However, they are hindered by the limited capacity and inferior phase transition due to the gliding of transition-metal layers upon Na + extraction and insertion in the cathode materials. Here, we report that the large-sized K + is riveted in the prismatic Na + sites of P2-Na 0.612 K 0.056 MnO 2 to enable more thermodynamically favorable Na + vacancies. The Mn-O bonds are reinforced to reduce phase transition during charge and discharge. 0.901 Na + per formula are reversibly extracted and inserted, in which only the two-phase transition of P2 ↔ P’2 occurs at low voltages. It exhibits the highest specific capacity of 240.5 mAh g −1 and energy density of 654 Wh kg −1 based on the redox of Mn 3+ /Mn 4+ , and a capacity retention of 98.2% after 100 cycles. This investigation will shed lights on the tuneable chemical environments of transition-metal oxides for advanced cathode materials and promote the development of sodium-ion batteries. High-capacity and structural stable cathode materials are challenges for sodium-ion batteries. Here, the authors report a layered P2-Na 0.612 K 0.056 MnO 2 with large-sized K + riveted in the Na-layers to enable 0.9 Na + (de)insertion with a reversible phase transition of P2-P’2.

Cross-modal retrieval, particularly image-text matching, is crucial in multimedia analysis and artificial intelligence, with applications in intelligent search and human-computer interaction. Current methods often overlook the rich semantic relationships between labels, leading to limited discriminability. We introduce a Two-Layer Graph Convolutional Network (L2-GCN) to model label correlations and a hybrid loss function, Circle-Soft, to enhance alignment and discriminability. Extensive experiments on the NUS-WIDE, MIRFlickr, and MS-COCO datasets demonstrate the effectiveness of our approach. The results show that the proposed method consistently outperforms current baselines, achieving accuracy improvements of 0.5%, 0.5%, and 1.0%, respectively. The source code is accessible via https://github.com/buzzcut619/L2-GCN-CIRCLE-SOFT.

Psychological and health-restorative benefits of mind-body therapies have been investigated, but their impact on the immune system remain less defined. To conduct the first comprehensive review of available controlled trial evidence to evaluate the effects of mind-body therapies on the immune system, focusing on markers of inflammation and anti-viral related immune responses. Data sources included MEDLINE, CINAHL, SPORTDiscus, and PsycINFO through September 1, 2013. Randomized controlled trials published in English evaluating at least four weeks of Tai Chi, Qi Gong, meditation, or Yoga that reported immune outcome measures were selected. Studies were synthesized separately by inflammatory (n = 18), anti-viral related immunity (n = 7), and enumerative (n = 14) outcomes measures. We performed random-effects meta-analyses using standardized mean difference when appropriate. Thirty-four studies published in 39 articles (total 2, 219 participants) met inclusion criteria. For inflammatory measures, after 7 to 16 weeks of mind-body intervention, there was a moderate effect on reduction of C-reactive protein (effect size [ES], 0.58; 95% confidence interval [CI], 0.04 to 1.12), a small but not statistically significant reduction of interleukin-6 (ES, 0.35; 95% CI, -0.04 to 0.75), and negligible effect on tumor necrosis factor-α (ES, 0.21; 95% CI, -0.15 to 0.58). For anti-viral related immune and enumerative measures, there were negligible effects on CD4 counts (ES, 0.15; 95% CI, -0.04 to 0.34) and natural killer cell counts (ES, 0.12, 95% CI -0.21 to 0.45). Some evidence indicated mind-body therapies increase immune responses to vaccination. Mind-body therapies reduce markers of inflammation and influence virus-specific immune responses to vaccination despite minimal evidence suggesting effects on resting anti-viral or enumerative measures. These immunomodulatory effects, albeit incomplete, warrant further methodologically rigorous studies to determine the clinical implications of these findings for inflammatory and infectious disease outcomes.

Introduction Blood–brain barrier (BBB) dysfunction may occur at the onset of Alzheimer’s disease (AD). Pericytes are a vital part of the neurovascular unit and the BBB, acting as gatekeepers of the BBB. Amyloid β (Aβ) deposition and neurofibrillary tangles in the brain are the central pathological features of AD. CD36 promotes vascular amyloid deposition and leads to vascular brain damage, neurovascular dysfunction, and cognitive deficits. However, the molecular mechanism by which pericytes of the BBB are disrupted remains unclear. Objectives To investigate the effect of low-dose Aβ1-40 administration on pericyte outcome and the molecular mechanism of BBB injury. Methods We selected 6-month-old and 9-month-old APP/PS1 mice and wild-type (WT) mice of the same strain, age, and sex as controls. We assessed the BBB using PET/CT. Brain pericytes were extracted and cocultured with endothelial cells (bEnd.3) to generate an in vitro BBB model to observe the effect of Aβ1-40 on the BBB. Furthermore, we explored the intracellular degradation and related molecular mechanisms of Aβ1-40 in cells. Results BBB permeability and the number of pericytes decreased in APP/PS1 mice. Aβ1-40 increased BBB permeability in an in vivo model and downregulated the expression of CD36, which reversed the Aβ-induced changes in BBB permeability. Aβ1-40 was uptaked in pericytes with high CD36 expression. We observed that this molecule inhibited pericyte proliferation, caused mitochondrial damage, and increased mitophagy. Finally, we confirmed that Aβ1-40 induced pericyte mitophagy-dependent ferroptosis through the CD36/PINK1/Parkin pathway. Conclusion PDGFRβ (a marker of pericytes), CD36, and Aβ colocalized in vitro and in vivo, and Aβ1-40 caused BBB disruption by upregulating CD36 expression in pericytes. The mechanism by which Aβ1-40 destroys the BBB involves the induction of pericyte mitophagy-dependent ferroptosis through the CD36/PINK1/Parkin pathway.

Cyclic dimeric guanosine monophosphate (c-di-GMP) serves as a bacterial second messenger that modulates various processes including biofilm formation, motility, and host-microbe symbiosis. Numerous studies have conducted comprehensive analysis of c-di-GMP. However, the mechanisms by which certain environmental signals such as iron control intracellular c-di-GMP levels are unclear. Here, we show that iron regulates c-di-GMP levels in Pseudomonas aeruginosa by modulating the interaction between an iron-sensing protein, IsmP, and a diguanylate cyclase, ImcA. Binding of iron to the CHASE4 domain of IsmP inhibits the IsmP-ImcA interaction, which leads to increased c-di-GMP synthesis by ImcA, thus promoting biofilm formation and reducing bacterial motility. Structural characterization of the apo-CHASE4 domain and its binding to iron allows us to pinpoint residues defining its specificity. In addition, the cryo-electron microscopy structure of ImcA in complex with a c-di-GMP analog (GMPCPP) suggests a unique conformation in which the compound binds to the catalytic pockets and to the membrane-proximal side located at the cytoplasm. Thus, our results indicate that a CHASE4 domain directly senses iron and modulates the crosstalk between c-di-GMP metabolic enzymes. The second messenger c-di-GMP regulates various processes in bacteria, including biofilm formation and motility. Here, the authors show that iron regulates c-di-GMP levels in Pseudomonas aeruginosa by modulating the interaction between an iron-sensing protein and a diguanylate cyclase.

Clinical efficacy of treatments against non-obstructive azoospermia (NOA), which affects 1% of men, are currently limited by the incomplete understanding of NOA pathogenesis and normal spermatogenic microenvironment. Here, we profile >80,000 human testicular single-cell transcriptomes from 10 healthy donors spanning the range from infant to adult and 7 NOA patients. We show that Sertoli cells, which form the scaffold in the testicular microenvironment, are severely damaged in NOA patients and identify the roadmap of Sertoli cell maturation. Notably, Sertoli cells of patients with congenital causes (Klinefelter syndrome and Y chromosome microdeletions) are mature, but exhibit abnormal immune responses, while the cells in idiopathic NOA (iNOA) are physiologically immature. Furthermore, we find that inhibition of Wnt signaling promotes the maturation of Sertoli cells from iNOA patients, allowing these cells to regain their ability to support germ cell survival. We provide a novel perspective on the development of diagnostic methods and therapeutic targets for NOA. Non-obstructive azoospermia affects 1% of men. Here, authors perform single-cell transcriptomic analysis of human testicular cells from healthy donors and non-obstructive azoospermia patients and find that inhibition of Wnt signaling promotes the maturation of Sertoli cells from patients.

Renewable energies, such as solar and wind, have been explored and widely applied for alleviating problems associated with the depletion of fossil fuel resources and environmental pollution. The intermittent and fluctuating features of these renewable energies require development of efficient energy storage and conversion systems. Sodium‐ion batteries (SIBs) are considered one of the most promising candidates for large‐scale energy storage due to the low cost and earth abundance of sodium resources. A major challenge for the practical application of SIBs is the development of appropriate cathodes with high energy densities and cycling stabilities. Layered oxide cathodes have received significant attention because of their relatively simple synthetic routes and high capacities stemming from their layered structures. However, they often suffer from moisture sensitivity and structural degradation upon repeated Na+ insertion/extraction, leading to severe performance fading. This review summarizes and discusses the degradation mechanisms of these layered oxide cathodes and modulation strategies for addressing the stability issues. Understanding the mechanisms behind structural instability would provide better insight for improving SIBs' cathode materials, which has critical implications for the designs and applications of SIBs as renewable energy systems. In this review, the main degradation mechanisms of layered oxide materials are analyzed, including Na+/vacancy ordering, irreversible phase transitions, and transition‐metal ion migration/dissolution. Relative modulation strategies are also summarized, providing an in‐depth understanding of the relationship between material structures and electrochemical performances to help design suitable cathode materials for sodium‐ion batteries.

The purpose of this study was to investigate the effect of the HXBM408 bacteria on the diversity of rat intestinal bacteria and the metabolism of soybean isoflavones. The control group was administered sterilized water and daidzein by gavage for 7 days. Conversely, the experimental group was administered HXBM408 solution and daidzein by gavage for 7 days. The content of the daidzein metabolite equol in rat feces in the experimental group was significantly higher than that in the control group ( P < 0.05) on the 7th and 14th days. However, the content of daidzein and its metabolites in feces was not significantly different ( P > 0.05). On the 7th day, the relative abundance of Streptococcus in the feces of the experimental group was significantly higher than that of the control group ( P < 0.05), but the difference disappeared over time ( P > 0.05). In the intestinal digesta of rats, the proteobacteria of the experimental group was significantly lower than those of the control group ( P < 0.05). HXBM408 can increase the degradation ability of soybean isoflavones in a short period after ingestion, increase the number of beneficial intestinal flora, and improve the structure of the flora.