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Carbon-based metal-free catalysts are promising green catalysts for photocatalysis and electrocatalysis due to their low cost and environmental friendliness. A key challenge in utilizing these catalysts is identifying their active sites, given their poor crystallinity and complex structures. Here we demonstrate the key structure of the double-bonded conjugated carbon group as a metal-free active site, enabling efficient O2 photoreduction to H2O2 through a cascaded water oxidation - O2 reduction process. Using ethylenediaminetetraacetic acid as a precursor, we synthesized various carbon-based photocatalysts and analyzed their structural evolution. Under the polymerization conditions of 260 °C to 400 °C, an N-ethyl-2-piperazinone-like structure was formed on the surface of the catalyst, resulting in high photocatalytic H2O2 photoproduction (2884.7 µmol g-1h-1) under visible light. A series of control experiments and theoretical calculations further confirm that the double-bond conjugated carbonyl structure is the key and universal feature of the active site of metal-free photocatalysts.

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The Ti3C2 quantum dots (QDs)/oxygen-vacancy-rich BiOBr hollow microspheres composite photocatalyst was prepared using solvothermal synthesis and electrostatic self-assembly techniques. Together, Ti3C2QDs and oxygen vacancies (OVs) enhanced photocatalytic activity by broadening light absorption and improving charge transfer and separation processes, resulting in a significant performance boost. Meanwhile, the photocatalytic efficiency of Ti3C2 QDs/BiOBr-OVs is assessed to investigate its capability for oxygen evolution and degradation of tetracycline (TC) and Rhodamine B (RhB) under visible-light conditions. The rate of oxygen production is observed to be 5.1 times higher than that of pure BiOBr-OVs, while the photocatalytic degradation rates for TC and RhB is up to 97.27% and 99.8%, respectively. The synergistic effect between Ti3C2QDs and OVs greatly enhances charge separation, leading to remarkable photocatalytic activity. Furthermore, the hollow microsphere contributes to the enhanced photocatalytic performance by facilitating multiple light scatterings and providing ample surface-active sites. The resultant Ti3C2QDs/BiOBr-OVs composite photocatalyst demonstrates significant potential for environmental applications.

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CRISPR-Cas9 editing triggers activation of the TP53-p21 pathway, but the impacts of different editing components and delivery methods have not been fully explored. In this study, we introduce a p21-mNeonGreen reporter iPSC line to monitor TP53-p21 pathway activation. This reporter enables dynamic tracking of p21 expression via flow cytometry, revealing a strong correlation between p21 expression and indel frequencies, and highlighting its utility in guide RNA screening. Our findings show that p21 activation is significantly more pronounced with double-stranded oligodeoxynucleotides (ODNs) or adeno-associated viral vectors (AAVs) compared to their single-stranded counterparts. Lentiviral vectors (LVs) and integrase-defective lentiviral vectors (IDLVs) induce notably lower p21 expression than AAVs, suggesting their suitability for gene therapy in sensitive cells such as hematopoietic stem cells or immune cells. Additionally, specific viral promoters like SFFV significantly amplify p21 activation, emphasizing the critical role of promoter selection in vector development. Thus, the p21-mNeonGreen reporter iPSC line is a valuable tool for assessing the potential adverse effects of gene editing methodologies and vectors.

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OBJECTIVES: To establish a rapid, accurate, and sensitive multiplex PCR detection method for the simultaneous identification of the six common edible meats (beef, lamp, chicken, pork, goose, duck), and to evaluate its application value in meat adulteration identification. METHODS: Based on complete mitochondrial genomic sequences of six species in the GenBank database, DNA sequences (cattle：16S rRNA; sheep：COX-1; chickens：Cytb; pig：COX-1; goose：NADH2; duck：16S rRNA) with intra-species conservation and inter-species specificity were screened, and species-specific primers were designed to construct a multiplex PCR detection system that can simultaneously detect the meat of six common species. The species specificity, sensitivity and reproducibility of the system were studied, and the simulated mixture sample detection was performed. RESULTS: This study successfully constructed a multiplex PCR detection system that can detect the meats of six common species simultaneously. The system was not effective in DNA amplification of non-target species. When the DNA template sizes were 0.062 5-2 ng/µL, the amplified products of all six species could be detected. The duck component was still detected when the mixing ratio of duck and beef was as low as 0.5%. CONCLUSIONS: This study constructs and establishes a multiplex PCR detection system with strong specificity, high sensitivity, and good reproducibility. It can accurately identify the components of animal origin in common edible meats and provide a simple and practical method for identifying adulteration of common edible meats and meat products in China.

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Bone marrow (BM) is the dominant site of hematopoiesis after 20 post-conception weeks (PCWs), but the intricacies of hematopoietic development in fetal BM up to birth and its involvement in malignancies remain unknown. Here, we compared the single-cell transcriptomic profile of BM hematopoietic stem and progenitor cells (HSPCs) at the early (12-14 PCW), middle (19-22 PCW) second trimester, and the neonatal stage. The stemness of hematopoietic stem cell and multipotent progenitor (HSC/MPP) is established at the middle second trimester, then maintained until birth. Furthermore, differentiation potentials toward three lineages are enhanced after the middle second trimester for birth, accompanied by the upregulation of aerobic metabolism. Notably, decreased stemness in HSCs/MPPs and higher interferon signals in progenitors at the early second trimester rendered the HSPCs more proximal to leukemogenesis. Collectively, our work elucidated the dynamics of fetal hematopoiesis in preparation for birth, offering valuable insights into the pathological processes underlying leukemia.

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BACKGROUND: This paper reports a rare presentation of multiple pulp stones (PSs) emerging in all teeth during mixed dentition. It offers valuable insights into the clinical diagnosis, treatment, and prognosis of multiple PSs, shedding light on their occurrence during the mixed dentition period. CASE SUMMARY: A 10-year-old girl presented with repeated pain in the mandibular right posterior teeth. Intraoral examination revealed carious lesions, abnormal tooth shapes, and anomalies in tooth number. Radiographic examinations showed multiple PSs with diverse shapes, sizes, and quantities in all teeth, alongside anomalies in tooth shape and number. Root canal therapy was initiated, but the patient initially lacked timely follow-up. Upon return for treatment completion, an extracted tooth revealed irregular calculus within the pulp cavity. CONCLUSION: This case underscores the importance of considering multiple PSs in mixed dentition, necessitating comprehensive evaluation and management strategies.

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Solid polymer electrolytes (SPEs) represent a pivotal advance toward high-energy solid-state lithium metal batteries. However, inadequate interfacial contact remains a significant bottleneck, impeding scalability and application. Inadequate interfacial contact remains a significant bottleneck, impeding scalability and application. Recent efforts have focused on transforming liquid/solid interfaces into solid/solid ones through in situ polymerization, which shows potential especially in reducing interface impedance. Here, we designed high-voltage SSLMBs with dual-reinforced stable interfaces by combining interface modification with an in situ polymerization technology inspired by targeted effects in medicine. Theoretical calculations and time-of-flight secondary ion mass spectrometry (TOF-SIMS) analysis demonstrate that tetramethylene sulfone (TMS) and bis(2,2,2-trifluoromethyl) carbonate (TFEC) exhibit selective adsorption at the interface of the LiNi0.8Co0.1Mn0.1O2 (NCM) cathode and Li anode, respectively. These compounds further decompose to form a stable cathode-electrolyte interface (CEI) film and a solid electrolyte interface (SEI) film, thereby simultaneously achieving a superior interface between the SPE and both the Li anode and NCM cathode. The developed Li||SPE||Li cell sustained cycling for more than 1000 h at 0.3 mA cm-2, and the NCM||SPE||Li cell also demonstrated an excellent capacity retention of 86.8% after 1000 cycles at 1 °C. This work will provide valuable insights for the rational design of high-voltage SSLMBs with stable interfaces, leveraging in situ polymerization as a cornerstone technology.

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The challenge of inadequate mechano-electrochemical stability in rechargeable fibrous Zn-ion batteries (FZIBs) has emerged as a critical challenge for their broad applications. Traditional rigid Zn wires struggle to maintain a stable electrochemical interface when subjected to external mechanical stress. To address this issue, a wet-spinning technique has been developed to fabricate Zn powder based fibrous anode, while carbon nanotubes (CNTs) introduced to enhance the spinnability of Zn powder dispersion. The followed annealing treatment has been conducted to reengineer the Zn crystalline texture with CNTs assisted surface tension regulation to redirect (002) crystallographic textural formation. The thus-derived annealed Zn@CNTs fiber demonstrates great mechano-electrochemical stability after a long-term bending and electrochemical process. The fabricated FZIB demonstrates a remarkable durability, surpassing 800 h at 1 mA cm-2 and 1 mAh cm-2, with a marginal voltage hysteresis increase of 21.7 mV even after 100 twisting cycles under 180 degree twisting angle. The assembled FZIB full cell displays an 88.6% capacity retention even after a long cycle of a series of bending, knotting, and straightening deformation. It has been also woven into a 200 cm2 size textile to demonstrate its capability to integrate into smart textiles.

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Enhancing the velocity of the oxidation-reduction cycle is crucial for improving the catalytic efficiency of Fenton processes. Therefore, the development of an effective strategy for wastewater degradation at low temperatures is essential. In this context, we present the preparation of an NH2-MIL-88B (Fe)/CuInS2 S-scheme heterojunction. Specifically, CuInS2 nanoparticles are introduced onto the Ferro-organic skeleton, resulting in the exposure of a significant number of active surface sites. Furthermore, NH2-MIL-88B (Fe)/CuInS2 demonstrates an extended photoresponse into the long-wavelength region, which contributes to its excellent photothermal properties. Notably, the degradation rate of tetracycline in low-temperature aqueous environments reaches as high as 99.7 %, several times higher than that of the original sample. Additionally, the hydrogen production of NH2-MIL-88B (Fe)/CuInS2 is 2.23 times that of single NH2-MIL-88B (Fe) and 3.46 times that of single CuInS2. Moreover, the system exhibits good H2O2 evolution performance, forming an efficient photo-Fenton system. The charge transfer process in S-scheme heterojunction is confirmed using in-situ X-ray photoelectron spectroscopy and electron paramagnetic resonance. Both transient photoluminescence and photo electrochemical tests further validate the enhanced photoelectrochemical properties of the NH2-MIL-88B (Fe)/CuInS2 S-scheme heterojunction. The exceptional performance of this system can be attributed to the synergistic effects of the S-scheme heterojunction and the bimetallic codoped photo-Fenton system. This research presents a novel approach for the breakdown of low-temperature wastewater using an improved photocatalytic Fenton system.

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The mechanical performance of curved bridges under the action of an earthquake is complex. To obtain the influence of seismic parameters on the seismic response of curved girder bridges, this paper relies on a large slope small-radius curved steel box girder bridge (LSCGB) and selects seismic wave incidence angle, vertical component of ground motion, and site category as seismic parameters to carry out nonlinear time history analysis. Based on the analysis results of the case bridge, it is shown that the torsional vibration of the first 10 modes of LSCGB is significant, the modes are dispersed, and the contribution of high-order modes of vibration cannot be ignored. The most unfavorable seismic wave incidence angle is in the direction of 45°âˆ¼60° counterclockwise Angle from the central connection line of Pier No. 1 and Pier No. 4 of the bridge. The seismic response of the curved bridge components increases with the vertical seismic intensity, and the influence on displacement responses is more significant. The basic vibration period of curved girder bridges built on soft soil sites is extended by approximately 18.23%, and the seismic response of key components increases with the softening of the site soil. Therefore, when analyzing the seismic response of LSCGBs, the influence of vertical component of ground motion and site category should not be ignored.

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High-voltage Li metal batteries (LMBs) based on ether electrolytes hold potential for achieving high energy densities exceeding 500 Wh kg-1, but face challenges with electrolyte oxidative stability, particularly concerning aluminum (Al) current collector corrosion. However, the specific chemistry behind Al corrosion and its effect on electrolyte components remains unexplored. Here, our study delves into Al corrosion in the representative LiFSI-DME electrolyte system, revealing that low-concentration electrolytes exacerbate Al current collector corrosion and solvent decomposition. In contrast, high-concentration electrolytes mitigate these issues, enhancing long-term stability. Remarkably, LiFSI-0.7DME electrolyte demonstrates exceptional stability with up to 1000 cycles at high voltage without significant capacity decay. These findings offer crucial insights into Al corrosion mechanisms in ether-based electrolytes, advancing our comprehension of high-voltage LMBs and facilitating their development for practical applications.

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Resolving the detailed structures of metal organic frameworks is of great significance for understanding their structure-property relation. Real-space imaging methods could exhibit superiority in revealing not only the local structure but also the bulk symmetry of these complex porous materials, compared to reciprocal-space diffraction methods, despite the technical challenges. Here we apply a low-dose imaging technique to clearly resolve the atomic structures of building units in a metal-organic framework, MIL-125. An unexpected node structure is discovered by directly imaging the rotation of Ti-O nodes, different from the unrotated structure predicted by previous X-ray diffraction. The imaged structure and symmetry can be confirmed by the structural simulations and energy calculations. Then, the distribution of node rotation from the edge to the center of a MIL-125 particle is revealed by the image analysis of Ti-O rotation. The related defects and surface terminations in MIL-125 are also investigated in the real-space images. These results not only unraveled the node symmetry in MIL-125 with atomic resolution but also inspired further studies on discovering more unpredicted structural changes in other porous materials by real-space imaging methods.

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Electrochemical reduction of CO into valuable multicarbon (C2+) liquids is crucial for reducing CO2 emissions and advancing clean energy, yet mastering efficiency and selectivity in this process remains a tough challenge. Herein, we employ a surface-modification strategy using electrochemically active polymeric 1,4,5,8-naphthalenete-tracarboxylic dianhydride (PNTCDA)-modified copper nanosheets (PM-Cu) to rearrange reactive species in the electric double layer, where the PNTCDA triggers a distinctive enolization that anchor potassium ions (K+) onto the cathode surface under reduction condition. Electrochemical analysis and computational simulations revealed that this approach fine-tunes K+ distribution in the double layer, making the dehydration of hydrated K+ more efficient and reducing active water molecules at the interface, thus inhibiting the hydrogen evolution reaction while concurrently promoting CO reduction via enhanced C‒C coupling. For the first time, the PM-Cu catalyst demonstrates ampere-scale current densities with the exclusive selectivity of a C2+ liquid product yield exceeding 90%. Thus, by tailoring the local microenvironment with electrochemically active organics, it is possible to modulate CO reduction, improve sustainable energy storage, and increase industrial carbon utilization.

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Although para-aminosalicylic acid (PAS) has been used to treat tuberculosis for decades, mechanisms of resistance to this drug in Mycobacterium tuberculosis (M. tuberculosis) clinical isolates have not been thoroughly investigated. Previously, we found that decreased methylenetetrahydrofolate reductase (MTHFR) activity of Rv2172c led to increased sensitivity to antifolates in M. tuberculosis. In this study, we collected the genome-sequencing data of 173 PAS-resistant and 803 PAS-sensitive clinical isolates and analyzed rv2172c mutations in those 976 isolates. The results showed that two mutations (T120P and M172V) on rv2172c could be identified in a certain proportion (6.36%) of PAS-resistant isolates. The results of AlphaFold2 prediction indicated that the T120P or M172V mutation might affect the enzymatic activity of Rv2172c by influencing nicotinamide adenine dinucleotide (NADH) binding, and this was verified by subsequent biochemical analysis, demonstrating the role of residues Thr120 and Met172 on NADH binding and enzymatic activity of Rv2172c. In addition, the effect of rv2172c T120P or M172V mutation on methionine production and PAS resistance was determined in M. tuberculosis. The results showed that both T120P and M172V mutations caused increased intracellular methionine concentrations and high level PAS resistance. In summary, we discovered new molecular markers and also a novel mechanism of PAS resistance in M. tuberculosis clinical isolates and broadened the understanding of the NADH-dependent MTHFR catalytic mechanism of Rv2172c in M. tuberculosis, which will facilitate the molecular diagnosis of PAS resistance and also the development of new drugs targeting Rv2172c.

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The inner Helmholtz plane and thus derived solid-electrolyte interphase (SEI) are crucial interfacial structure to determine the electrochemical stability of Zn-ion battery (ZIB). In this work, we demonstrate that introducing ß-cyclodextrins (CD) as anion-receptors into Zn(OTf)2 aqueous electrolyte could significantly optimize the Zn anode SEI structure for achieving stable ZIB. Specifically, ß-CD with macrocyclic structure holds appropriate cavity size and charge distribution to encase OTf- anions at the Zn metal surface to form ß-CD@OTf- dominated inner Helmholtz structure. Meanwhile, the electrochemically triggered ß-CD@OTf- decomposition could in situ convert to the organic-inorganic hybrid SEI (ZnF2/ZnCO3/ZnS‒(C-O-C/*CF/*CF3)), which could efficiently hinder the Zn dendrite growth with maintain the proper SEI mechanical strength stability to guarantee the long-term stability. The thus-derived Zn | |Zn pouch cell (21 cm2 size) with ß-CD-containing electrolyte exhibits a cumulative capacity of 6450 mAh-2 cm-2 at conditions of 10 mAh cm-2 high areal capacity. This work gives insights for reaching stable ZIB via electrolyte additive triggered SEI structure regulation.

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As one of the factors affecting the treatment outcomes, drug tolerance in mycobacteriosis has not been paid due attention. Genome-wide association studies on 607 Mycobacterium tuberculosis clinical isolates with phenotypic drug susceptibility test data revealed that a K114N mutation on the rv2820c gene was highly enriched in capreomycin-resistant isolates (32/213, 15.02%). However, the mutation was also observed in capreomycin-sensitive isolates (10/394, 2.53%). In most cases (31/42, 73.81%), the rv2820c K114N mutation occurred in isolates with the known capreomycin resistance conferring mutation rrs A1401G. In contrast, the general frequency of the rv2820c K114N mutation was low in 7061 genomes downloaded from the National Center for Biotechnology Information database. To determine the impact of this mutation on the antimycobacterial activity of capreomycin, the intact rv2820c gene and the rv2820c K114N mutant were over-expressed in Mycobacterium smegmatis (Ms), and the results of susceptibility tests showed that the rv2820c K114N mutation did not affect the minimum inhibition concentration (MIC) of capreomycin. Subsequently, the data of time-kill assays showed that, it took only 2 h of capreomycin treatment (40 µg/ml, 5 × MIC) to kill 99.9% bacterial cells of Ms MC2155 pMV261::rv2820cH37Rv, while it took 6 h to achieve that for Ms MC2155 pMV261::rv2820cK114N. Taken together, these data suggested that the rv2820c K114N mutation is related with capreomycin tolerance, which merits further investigation.

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OBJECTIVE: Upper urinary tract stones (UUTSs) are among the most common types of urinary stones, and their incidence rate has been increasing annually in recent years, seriously affecting the daily lives of patients. This study aimed to compare the treatment efficacy of one-stage and staged flexible ureteroscopic lithotripsy (FURL) for UUTSs. METHODS: A total of 142 patients with UUTSs admitted to our hospital between December 2019 and March 2023 were selected for retrospective analysis, including 76 patients who received staged FURL (control group) and 66 patients who received one-stage FURL (observation group). The duration of surgery, length of stay, stone clearance rate, incidence of postoperative complications (from postsurgery to discharge), and total hospitalization cost were analyzed in both groups. The visual analog scale (VAS) score and activities of daily living (ADL) score were assessed before surgery (T0), 3 days after surgery (T1), and 7 days after surgery (T2). Patients were followed up for 1 month after surgery, and their quality of life was assessed using the MOS Item Short Form Health Survey (SF-36). RESULTS: There was no difference in the stone clearance rate or incidence of postoperative complications between the two groups (p > 0.05). The operation time, hospitalization time and hospitalization cost in the observation group were 75.58 ± 15.91 min, 4.20 ± 1.24 days and 14312.62 ± 1078.89 yuan, respectively, which were lower than those in the control group (p < 0.05). In addition, the VAS score at T3 was decreased to 1.49 ± 0.70, while the ADL and SF-36 scores were higher in the observation group (p < 0.05). CONCLUSIONS: One-stage FURL shortens the duration of surgery and length of stay, reduces hospitalization costs, and improves the quality of life of patients with UUTSs.

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Efficient and accurate acquisition of the rice grain protein content (GPC) is important for selecting high-quality rice varieties, and remote sensing technology is an attractive potential method for this task. However, the majority of multispectral sensors are poor predictors of GPC due to their broad spectral bands. Hyperspectral technology provides a new analytical technology for bridging the gap between phenomics and genomics. However, the small size of typical datasets is a constraint for model construction for estimating GPC, limiting their accuracy and reducing their ability to generalize to a wide range of varieties. In this study, we used hyperspectral data of rice grains from 515 japonica varieties and deep convolution generative adversarial networks (DCGANs) to generate simulated data to improve the model accuracy. Features sensitive to GPC were extracted after applying a continuous wavelet transform (CWT), and the estimated GPC model was constructed by partial least squares regression (PLSR). Finally, a genome-wide association study (GWAS) was applied to the measured and generated datasets to detect GPC loci. The results demonstrated that the simulated GPC values generated after 8,000 epochs were closest to the measured values. The wavelet feature (WF1743, 2), obtained from the data with the addition of 200 simulated samples, exhibited the highest GPC estimation accuracy (R 2 = 0.58 and RRMSE = 6.70%). The GWAS analysis showed that the estimated values based on the simulated data detected the same loci as the measured values, including the OsmtSSB1L gene related to grain storage protein. This study provides a new technique for the efficient genetic study of phenotypic traits in rice based on hyperspectral technology.