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This research explored the origin and paleoenvironmental significance of sediments from the Cosmonaut Sea, Antarctica, focusing on the period since the Last Glacial Maximum (LGM, 26,000 cal a BP). Sediment samples from core ANT37-C5/6-07 were subjected to AMS 14 C dating, clay-mineral assemblage analysis, grain size evaluation, and geochemical testing. Results indicated illite as the dominant clay mineral (average 46%), followed by kaolinite (22%) and smectite (21%), with chlorite (11%) being the least abundant. Comparison with previous studies suggested that these sediments are largely derived from weathered material from Prydz Bay and Enderby Land coastal regions. The study of mineral ratios, geochemical elements, and sediment grain size, alongside δ 18 O values from the East Antarctica EDML ice core, revealed that the ice sheet in the study area retreated around 18600 cal a BP, melted more markedly during 16800-15000 cal a BP, tended to expand during 14800-13500 cal a BP, and then the ice sheet remained in a state of retreat until it expanded again around 5000 cal a BP. It is largely synchronous with the phased changes in the Antarctic climate since the LGM (26ka) of the Cosmonaut Sea. Notably, the sediment record aligns with major paleoclimatic events, including Heinrich Stadial 1 and the Younger Dryas in the northern hemisphere and the Antarctic cold reversal, reflecting a climatic ‘seesaw’ effect. These findings suggest that the sedimentary record in the Cosmonaut Sea is a sensitive indicator of climatic conditions, highlighting a history of glacial movements and revealing East Antarctica’s climatic fluctuations. Additionally, the research indicates that the regional ice sheet is more sensitive to climatic changes than previously believed, underscoring its instability.

This research delves into the interaction between carbon isotopes, ice-rafted debris (IRD), and Circumpolar Deep Water (CDW) in the Amundsen Sea, West Antarctic. Utilizing sediment core ANT36-A11-04, we traced the source of the organic matter though an analysis of the total organic carbon (TOC), stable carbon isotopes (δ 13 C org ), and nitrogen content. We identified six environmental events in this region since the Mid-Holocene, which were discerned through a comparative analysis of the δ 13 C org , TOC, and IRD content. These events were closely linked to variations in the intensity of the CDW. Notably, the synchronous occurrence of a negative shift in the δ 13 C org value and increases in TOC and IRD highlight the significant impact of CDW intrusion, underlining the pivotal role of the CDW in the regional environmental evolution. Specifically, intensified upwelling of the CDW was correlated with increased heat and nutrients, enhanced glacier melting, phytoplankton blooms, higher TOC content, augmented deposition of IRD, and finally resulted in a negative shift in the δ 13 C org value. We present a comprehensive picture of the local environmental evolution in the Amundsen Sea, characterized as a marine-glacial-biological coupling model, thereby contributing to a broader understanding of Antarctic environmental dynamics.

Complete ammonia oxidation (comammox) bacteria can complete the whole nitrification process independently, which not only challenges the classical two-step nitrification theory but also updates long-held perspective of microbial ecological relationship in nitrification process. Although comammox bacteria have been found in many ecosystems in recent years, there is still a lack of research on the comammox process in rhizosphere of emergent macrophytes in lakeshore zone. Sediment samples were collected in this study from rhizosphere, far-rhizosphere, and non-rhizosphere of emergent macrophytes along the shore of Lake Liangzi, a shallow lake. The diversity of comammox bacteria and amoA gene abundance of comammox bacteria, ammonia-oxidizing archaea (AOA), and ammonia-oxidizing bacteria (AOB) in these samples were measured. The results showed that comammox bacteria widely existed in the rhizosphere of emergent macrophytes and fell into clade A.1, clade A.2, and clade B, and clade A was the predominant community in all sampling sites. The abundance of comammox amoA gene (6.52 × 106–2.45 × 108 copies g−1 dry sediment) was higher than that of AOB amoA gene (6.58 × 104–3.58 × 106 copies g−1 dry sediment), and four orders of magnitude higher than that of AOA amoA gene (7.24 × 102–6.89 × 103 copies g−1 dry sediment), suggesting that the rhizosphere of emergent macrophytes is more favorable for the growth of comammox bacteria than that of AOB and AOA. Our study indicated that the comammox bacteria may play important roles in ammonia-oxidizing processes in all different rhizosphere regions.

Large Language Models (LLMs) have demonstrated promising capabilities for code generation. While existing benchmarks evaluate the correctness and efficiency of LLM-generated code, the potential linguistic bias - where code quality varies based on the natural language used to describe programming tasks - remains underexplored. In this paper, we aim to investigate this linguistic bias through the lens of English and Chinese. To facilitate our investigation, we present a unified evaluation framework comprising a curated dataset of 52 Python programming questions with parallel bilingual task descriptions, automated correctness verification, and efficiency quantification tools based on runtime complexity estimation. Based on this framework, we conduct the first empirical study towards the linguistic bias in LLM-generated code on eight popular LCGMs, as well as GPT-3.5-Turbo and GPT-4. We observe that these LCGM-generated code show different correctness on an average of 12% bilingual programming tasks, where 39% also exhibits diverse efficiency. Our findings indicate that LLMs commonly exhibit linguistic bias for code generation.

In recent years, Large Language Models (LLMs) have faced increasing demands to selectively remove sensitive information, protect privacy, and comply with copyright regulations through unlearning, by Machine Unlearning. While evaluating unlearning effectiveness is crucial, existing benchmarks are limited in scale and comprehensiveness, typically containing only a few hundred test cases. We identify two critical challenges in generating holistic audit datasets: ensuring audit adequacy and handling knowledge redundancy between forget and retain dataset. To address these challenges, we propose HANKER, an automated framework for holistic audit dataset generation leveraging knowledge graphs to achieve fine-grained coverage and eliminate redundant knowledge. Applying HANKER to the popular MUSE benchmark, we successfully generated over 69,000 and 111,000 audit cases for the News and Books datasets respectively, identifying thousands of knowledge memorization instances that the previous benchmark failed to detect. Our empirical analysis uncovers how knowledge redundancy significantly skews unlearning effectiveness metrics, with redundant instances artificially inflating the observed memorization measurements ROUGE from 19.7% to 26.1% and Entailment Scores from 32.4% to 35.2%, highlighting the necessity of systematic deduplication for accurate assessment.

Due to its essential roles in angiogenesis, Notch pathway has emerged as an attractive target for the treatment of pathologic angiogenesis. Although both activation and blockage of Notch signal can impede angiogenesis, activation of Notch signal may be more promising because it was shown that long-term Notch signal blockage resulted in vessel neoplasm. However, an in vivo deliverable Notch ligand with highly efficient Notch-activating capacity has not been developed. Among all the Notch ligands, Delta-like4 （Dll4） is specifically involved in angiogenesis. In this study, we generated a novel soluble Notch ligand hD4R, which consists of the Delta-Serrate-Lag-2 fragment of human Dll4 and an arginine-glycine-aspartate （RGD） motif targeting endothelial cells （ECs）. We demonstrated that hD4R could bind to ECs through its RGD motif and effectively triggered Notch signaling in ECs. Further, we confirmed that hD4R could suppress angiogenesis in vitro as manifested by network formation assay and sprouting assay. More importantly, hD4R efficiently repressed neonatal retinal angiogenesis and laser-induced choroidal neovascularization （CNV） as well in vivo. In conclusion, we have developed an in vivo deliverable Notch ligand hD4R, which suppresses angiogenesis both in vitro and in vivo, thus providing a new approach to tackle exces- sive angiogenesis relevant disease such as CNV.

As global climate change intensifies with unprecedented urgency, nations worldwide have increasingly adopted market-based environmental regulatory instruments to advance carbon reduction objectives. In 2017, China launched energy rights trading pilots, thereby providing a crucial policy instrument for controlling total energy consumption at its source. However, the specific impacts and transmission pathways through which this system influences corporate carbon reduction behavior remain insufficiently explored through rigorous empirical investigation. Drawing upon panel data from heavy-polluting companies listed on the Shanghai and Shenzhen A-share markets, this study employs a difference-in-differences methodology to identify the causal effects of energy rights trading systems on corporate carbon reduction. Our findings reveal that energy rights trading systems significantly reduce corporate carbon emission intensity, generating pronounced emission reduction effects. Further mechanism analysis demonstrates that this system operates through two principal pathways: first, by promoting increased green investment among enterprises, whereby short-term emission reductions are achieved through procurement of energy-saving equipment and environmental protection facilities, and second, by stimulating corporate green technological innovation, whereby long-term sustainable emission reductions are realized through the development of energy-saving technologies and clean processes. Additionally, the research reveals that enterprises with lower financing constraints and stronger supply chain bargaining power respond more actively to policy implementation, with policy effects exhibiting significant heterogeneity. This study not only enriches the theoretical understanding of market-based environmental regulatory policy effects but also provides crucial empirical evidence for improving the energy rights trading system design and enhancing policy implementation effectiveness, thereby offering important policy insights for promoting corporate green transformation and achieving “dual carbon” objectives.

Electrochemiluminescence (ECL) is a light-emitting process in which the stability of electrochemically generated radicals has a crucial impact on the efficiency and durability of excited state generation. Therefore, deciphering a relationship between radical stability and ECL performance is highly appealing. In this work, three sp 2 carbon-conjugated covalent organic framework (COF) reticular nanoemitters compositing of same pyrene luminophores but different acrylonitrile linkers are designed with progressive electron affinities, named as CN-COF-1, 2, and 3. By precisely modulating the electron affinity of CN-COFs, a volcano relationship between ECL and radical stability is discovered with 78 folds enhancement in ECL intensity. Density functional theoretical calculations indicate that CN-COF-2 exhibits moderate radical stabilization capacity as well as efficient electron transport between the pyrene cores, facilitating ECL generation. Significantly, the appropriate radical stability of CN-COF-2 not only achieves the self-enhanced cathodic ECL but also promotes durability of the ECL intensity. The rational regulation of radical stability paves the way for developing efficient reticular nanoemitters and decoding the ECL fundamentals. Deciphering the relationship between radical stability and electrochemiluminescence performance is important since the stability of electrochemically generated radicals has an impact on the efficiency and durability of excited state generation. Here, the authors describe a volcano shaped relationship via modulating the electron affinity of three acrylonitrile-linked covalent organic frameworks.

The incidence of acute lung injury (ALI) following aortic dissection repair surgery that involves deep hypothermic circulatory arrest (DHCA) is notably high. We analyzed hub genes and signaling pathways in rat lung tissues post-DHCA using transcriptome sequencing and weighted gene co-expression network analysis (WGCNA). A rat model of DHCA was established, and lung tissues were collected after the procedure. High-throughput transcriptome sequencing was employed to assess gene expression differences between the DHCA group and the non-DHCA group. The DESeq2 method was utilized to analyze differentially expressed genes (DEGs) between these two groups, with further screening for hub genes and their upstream molecules conducted using WGCNA, protein-protein interaction (PPI) networks, and the iRegulon plugin. Biological functions of hub genes were examined via Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses. The changes in mRNA and protein levels of hub genes across both groups were evaluated through experimental verification. A total of 438 DEGs were identified when comparing the DHCA group to the control group. WGCNA further revealed 197 key genes. Subsequent PPI analysis led to the identification of eight hub genes: FOS, FOSB, JUN, EGR1, ATF3, NR4A1, CCN1, and ZFP36. The hub genes were primarily associated with inflammation, cell apoptosis, and cellular immune responses. ATF3 and SRF may serve as potential upstream regulators. The experimental findings further corroborated that substantial alterations took place in these hub genes, accompanied by significant injury of lung tissue during DHCA. DHCA significantly altered gene expression patterns in rat lung tissues. The identified hub genes and signaling pathways related to inflammation and apoptosis may serve as potential therapeutic targets for lung injury following DHCA.

The CRISPR-associated endonuclease Cas12a has become a powerful genome-editing tool in biomedical research due to its ease of use and low off-targeting. However, the size of Cas12a severely limits clinical applications such as adeno-associated virus (AAV)-based gene therapy. Here, we characterized a novel compact Cas12a ortholog, termed EbCas12a, from the metagenome-assembled genome of a currently unclassified Erysipelotrichia . It has the PAM sequence of 5′-TTTV-3′ (V = A, G, C) and the smallest size of approximately 3.47 kb among the Cas12a orthologs reported so far. In addition, enhanced EbCas12a (enEbCas12a) was also designed to have comparable editing efficiency with higher specificity to AsCas12a and LbCas12a in mammalian cells at multiple target sites. Based on the compact enEbCas12a, an all-in-one AAV delivery system with crRNA for Cas12a was developed for both in vitro and in vivo applications. Overall, the novel smallest high-fidelity enEbCas12a, this first case of the all-in-one AAV delivery for Cas12a could greatly boost future gene therapy and scientific research.