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Integrated Label-Free Proteomic and Genomic Analysis Reveals Laboratory Adaptive Co-Evolution and Bacterial Interactions in Tri-Species Microbial Communities
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Machine Learning Studies of Organic Reactions Catalyzed by Nickel Catalysts with Nitrogen-Containing Ligands
No full textUnlocking Ultralong Cycle Life and Temperature-Tolerable Secondary Batteries Using a Vacancy-Abundant Co<sub>9</sub>S<sub>8</sub>@ZnS/Carbon Anode
No full textSodium-ion batteries face some critical anode-level barriers: sluggish Na+ transport, conversion-induced instability, and poor temperature adaptability. Here, we develop a vacancy-based synergy in Co9S8@ZnS/C synthesized by metal–organic framework-templated sulfidation. The Co–Zn–S system provides sodiophilic vacancies that lower Na+ diffusion barriers and further strengthen the interfacial field. This self-reinforcing synergy is validated through in situ X-ray diffraction and in situ Raman spectroscopy, demonstrating reversible conversion/alloying and interfacial reconstruction. The Co9S8@ZnS/C anode delivers exceptional performance, including a high capacity of 458.7 mAh g–1 after 400 cycles at 1.0 A g–1 and a remarkable ultralong stability of 249.1 mAh g–1 after 4000 cycles at 15.0 A g–1, with robust operation from −10 to 50 °C. Full cells paired with Na3V2(PO4)3 demonstrate excellent stability, validating their practical viability. This work establishes a generalizable vacancy-abundant design principle that deterministically links defect thermodynamics and electrostatics to long-term Na storage across diverse operating conditions
Experimental and finite element studies of 3D-printed concrete-glued laminated timber composite beams
No full textThis study investigates a composite beam structure system combining glued laminated timber (GLT) and 3D-printed concrete (3DPC), which employs a notched-screw connection filled with ultra-high-performance concrete. Experimental results indicate that the distance from the beam end to the connection should be increased to prevent shear failure of the timber at the beam ends. Increasing the height of the 3DPC slab from 110 mm to 150 mm improves the overall stiffness and load-bearing capacity of the beam. With the incorporation of polyoxymethylene fibers, the material demonstrates ductile fracture behavior. Furthermore, the use of polyethylene fibers notably improves the ductility of 3DPC while also providing significant enhancement in crack resistance. Parameter analysis shows that increasing the height of the GLT beam is the most effective measure for enhancing both load-bearing capacity and stiffness, resulting in a maximum improvement of 43 %. The spacing between connections can be reduced to effectively improve the combination efficiency. An increase in the GLT strength grade enhances the load-bearing capacity but reduces ductility. In the serviceability and ultimate limit states, composite beams incorporating UHPC notches and screw connections exhibit composite action coefficients of approximately 78 % and 68 %, respectively. Compared with existing similar connection details, this configuration shows enhanced composite efficiency. To address the overestimation of bending stiffness by the γ method, this study validates a modified model that accounts for the non-uniform strain distribution induced by axial forces. Finally, regarding the bending failure mode at the bottom of the GLT beam, a formula for calculating the ultimate load-bearing capacity was established.</p
Terahertz spin torque nano-oscillator based on a ferrimagnetic skyrmion lattice
No full textSpin torque nano-oscillators have received continuously increasing attention due to their rich dynamics and potential applications. Here, we propose a spin torque nano-oscillator based on a ferrimagnetic skyrmion lattice, where the weak Magnus forces together with intriguing skyrmion-skyrmion interactions allow current-driven skyrmions to oscillate at terahertz frequencies. Through micromagnetic simulations, we demonstrate that a small current injection area results in identical motion orbits for the oscillating skyrmions, while a large injection area yields distinct or even chaotic trajectories. We analyze the transition between identical and distinct orbits using the Thiele equation, which also explains the parameter dependence of the oscillator frequency. In addition, synchronized oscillation signals emitted from a single oscillator are demonstrated. Our results not only reveal the high-frequency oscillation dynamics of ferrimagnetic skyrmions, but also pave the way for developing skyrmion-based oscillators.</p
Multimodal-based analysis of single-cell ATAC-seq data enables highly accurate delineation of clinically relevant tumor cell subpopulations
No full textBackground: Accurately identifying functionally distinct tumor cell subpopulations remains a critical challenge in cancer research. While single-cell epigenomics assays provide powerful insights into tumor heterogeneity beyond gene expression, computational limitations have hindered their application. Methods: We introduce Multimodal-based Analysis of scATAC-Seq data (MAAS), a method that integrates chromatin accessibility, copy number variations (CNVs), and single-nucleotide variants (SNVs) to identify functional tumor cell subpopulations. MAAS employs a self-expressive multimodal matrix factorization approach with rigorous coverage normalization and data denoising. We applied MAAS to simulated datasets and multiple real-world tumor scATAC-seq datasets, including pediatric ependymoma, B-cell lymphoma, and glioblastoma, and benchmarked its performance against existing integration methods. Functional relevance of subpopulation-specific genes was experimentally validated using gene knockdown and overexpression assays. Furthermore, we constructed subpopulation-specific gene regulatory networks and developed a prognostic signature from the key regulatory genes. Results: MAAS demonstrated superior accuracy in detecting clinically relevant subpopulations, particularly in tumors with limited CNV heterogeneity, such as pediatric ependymoma and B-cell lymphoma. In glioblastoma, MAAS uncovered a previously unrecognized subpopulation with temozolomide resistance and further experimentally validated the effects of its signature genes through gene knockdown and overexpression. The MAAS-derived prognostic signature, MAASig, outperformed traditional clinicopathologic features across multiple cancer types when applied to independent validation cohorts. Conclusions: By integrating multimodal information from scATAC-seq data, MAAS provides the robust identification of functionally distinct tumor cell subpopulations, facilitating the discovery of potential therapeutic targets.</p
Daily construction carbon emissions and costs assessment from an interaction perspective: Integration of BIM and agent-based modeling
No full textEffective management of construction carbon emissions and costs are important for achieving sustainable construction. The construction carbon emissions and costs are influenced by many non-design factors including worker performance, on-site management capability, and local weather conditions. However, the combined influence of these factors has not been fully considered in existing studies. Moreover, previous research typically aggregate carbon and cost results occurred at different times into single and static values, ignoring their potential dynamic changes throughout the construction process. This study integrates Building Information Modeling (BIM) with Agent-based Modeling (ABM) to establish a novel assessment model for daily construction carbon emissions and costs. The BIM model is employed to collect project data, while the ABM model simulates the interactions between workers, managers, building materials, machine equipment, and weather conditions as well as their subsequent effects on construction carbon emissions and costs. The proposed model was applied to a steel building to verify its operability. A series of targeted optimization strategies were proposed, and their carbon reduction and cost-saving potentials were quantified and compared using the BIM-ABM model. This study integrates BIM and ABM to estimate construction carbon emissions and costs, demonstrating the feasibility and operability of the integration. The proposed model not only considers the specific characteristics of the evaluated project but also presents the dynamic changes of construction carbon and costs on a daily basis, thereby significantly enhancing the accuracy and temporal resolution of results. It lays an important foundation for future studies and can promote sustainable construction.</p
A Dynamic Working Set Method for Compressed Sensing
No full textWe propose a dynamic working set method (DWS) for the problem minx∈Rn12‖Ax-b‖2+η‖x‖1 that arises from compressed sensing. DWS manages the working set while iteratively calling a regression solver to generate progressively better solutions. Our experiments show that DWS is more efficient than other state-of-the-art software in the context of compressed sensing. Scale space such that ‖b‖=1. Let s be the number of non-zeros in the unknown signal. We prove that for any given ε>0, DWS reaches a solution with an additive error ε/η2 such that each call of the solver uses only O(1εslogslog1ε) variables, and each intermediate solution has O(1εslogslog1ε) non-zero coordinates.</p
High-Performance Quasi-Solid-State Calcium-Ion Batteries from Redox-Active Covalent Organic Framework Electrolytes
No full textCalcium ion batteries (CIBs) are promising for energy storage with volumetric capacity and reduction potential comparable to lithium, while richer in earth abundance. However, sluggish cation transport and unstable cycling performance primarily due to anode surface passivation remain vital challenges for realizing high-performance CIBs. Herein, two kinds of redox covalent organic frameworks (PT-COFs and PQ-COFs) with different-density carbonyl groups are prepared as quasi-solid-state electrolytes (QSSEs) to address those challenges. In particular, PT-COFs exhibit ionic conductivity of 0.46 and 5.05 mS cm−1 at room temperature and 80 °C, respectively, and Ca2+ transference number of 0.532. Due to the efficient ionic conduction and intrinsic stability of PT-COFs structure, the prepared full calcium ion cell with PT-COFs demonstrates the highest reversible specific capacity of 155.9 mAh g−1 at 0.15 A g−1 (1 C), and stable cycle performance (capacity retention over 74.6% at 1 A g−1 after 1000 cycles). This work shows the effectiveness of the redox COFs and their promising potential as SSE for the development of high-performance CIBs.</p