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Oxygen-containing functional groups are nearly ubiquitous in complex small molecules. The installation of multiple C–O bonds by the concurrent oxygenation of contiguous C–H bonds in a selective fashion would be highly desirable but has largely been the purview of biosynthesis. Multiple, concurrent C–H bond oxygenation reactions by synthetic means presents a challenge 1 – 6 , particularly because of the risk of overoxidation. Here we report the selective oxygenation of two or three contiguous C–H bonds by dehydrogenation and oxygenation, enabling the conversion of simple alkylarenes or trifluoroacetamides to their corresponding di- or triacetoxylates. The method achieves such transformations by the repeated operation of a potent oxidative catalyst, but under conditions that are sufficiently selective to avoid destructive overoxidation. These reactions are achieved using electrophotocatalysis 7 , a process that harnesses the energy of both light and electricity to promote chemical reactions. Notably, the judicious choice of acid allows for the selective synthesis of either di- or trioxygenated products. Installation of multiple C–O bonds by concurrent oxygenation of contiguous C–H bonds in a selective fashion is highly desirable, and this is achieved by repeated operation of a potent oxidative catalyst via electrophotocatalysis.

Electrochemical oxygen reduction could proceed via either 4e − -pathway toward maximum chemical-to-electric energy conversion or 2e − -pathway toward onsite H 2 O 2 production. Bulk Pt catalysts are known as the best monometallic materials catalyzing O 2 -to-H 2 O conversion, however, controversies on the reduction product selectivity are noted for atomic dispersed Pt catalysts. Here, we prepare a series of carbon supported Pt single atom catalyst with varied neighboring dopants and Pt site densities to investigate the local coordination environment effect on branching oxygen reduction pathway. Manipulation of 2e − or 4e − reduction pathways is demonstrated through modification of the Pt coordination environment from Pt-C to Pt-N-C and Pt-S-C, giving rise to a controlled H 2 O 2 selectivity from 23.3% to 81.4% and a turnover frequency ratio of H 2 O 2 /H 2 O from 0.30 to 2.67 at 0.4 V versus reversible hydrogen electrode. Energetic analysis suggests both 2e − and 4e − pathways share a common intermediate of *OOH, Pt-C motif favors its dissociative reduction while Pt-S and Pt-N motifs prefer its direct protonation into H 2 O 2 . By taking the Pt-N-C catalyst as a stereotype, we further demonstrate that the maximum H 2 O 2 selectivity can be manipulated from 70 to 20% with increasing Pt site density, providing hints for regulating the stepwise oxygen reduction in different application scenarios. Controlling O 2 reduction pathways can help optimize catalytic activity and product selectivity. Here the authors report facile manipulation of 2e ‒ /4e ‒ pathways on Pt-coordinated motifs by varying the Pt site density or the coordination environment.

Non-homologous end joining (NHEJ) is a DNA repair pathway that directly ligates broken DNA ends without the need for a homologous template, whereas translesion synthesis (TLS) is a DNA damage tolerance mechanism in which specialized DNA polymerases bypass lesions on the template strand. Although both pathways play critical roles in maintaining genome integrity across organisms, they inherently introduce mutations. Here, we investigate how these two pathways contribute to spontaneous and genotoxic stress–induced genomic alterations in the yeast Yarrowia lipolytica . A NHEJ-deficient mutant ( ku70 ) and three TLS-deficient mutants ( rev1 , rev3 , and rad30 ) are subjected to mutation accumulation experiments, followed by whole-genome sequencing. Our results show that the deletion of KU70 has no significant effect on the rates of spontaneous single-nucleotide variations (SNVs), small insertions and deletions, or chromosomal rearrangements, while the deletion of REV1 and REV3 leads to significant reductions in spontaneous SNV rates. These findings indicate that TLS but not the NHEJ pathway is a major contributor to spontaneous mutagenesis in Y. lipolytica . Moreover, exposure to 0.02% methyl methanesulfonate and 80 J/m 2 ultraviolet (UV) radiation resulted in 48- and 107-fold increases in SNV rates, respectively. These induced SNVs were largely dependent on DNA polymerases Rev1 and ζ , further underscoring their central roles in genotoxic stress–induced mutagenesis. We observe that DNA polymerase η can suppress C to T and C to A substitutions while promoting T to C mutations, exhibiting a dual function in regulating mutagenesis under UV treatment. Phenotypic evolution experiments reveal that TLS activity enhances the adaptive potential of Y. lipolytica under oxidative stress, underlying its broader impact on environmental fitness. Together, these findings provide new insights into the distinct roles of the NHEJ and TLS pathways in preserving genome integrity in Y. lipolytica . Key points • The NHEJ pathway has a limited role in spontaneous genomic alterations in Y. lipolytica. • DNA polymerases Rev1 and ζ contribute to most UV- and MMS-induced mutations. • The dual roles of Pol η in UV-induced mutations were revealed. • NHEJ and TLS pathways are crucial to phenotypic evolution of Y. lipolytica.

HighlightsA freestanding MXene-derived defect-rich TiO2@reduced graphene oxides (M-TiO2@rGO) foam electrode was fabricated.M-TiO2@rGO presents fast Na+ storage kinetics due to capacitive contribution.M-TiO2@rGO foam electrode displays a capacity retention of 90.7% after 5000 cycles.Sodium ion batteries and capacitors have demonstrated their potential applications for next-generation low-cost energy storage devices. These devices's rate ability is determined by the fast sodium ion storage behavior in electrode materials. Herein, a defective TiO2@reduced graphene oxide (M-TiO2@rGO) self-supporting foam electrode is constructed via a facile MXene decomposition and graphene oxide self-assembling process. The employment of the MXene parent phase exhibits distinctive advantages, enabling defect engineering, nanoengineering, and fluorine-doped metal oxides. As a result, the M-TiO2@rGO electrode shows a pseudocapacitance-dominated hybrid sodium storage mechanism. The pseudocapacitance-dominated process leads to high capacity, remarkable rate ability, and superior cycling performance. Significantly, an M-TiO2@rGO//Na3V2(PO4)3 sodium full cell and an M-TiO2@rGO//HPAC sodium ion capacitor are fabricated to demonstrate the promising application of M-TiO2@rGO. The sodium ion battery presents a capacity of 177.1 mAh g−1 at 500 mA g−1 and capacity retention of 74% after 200 cycles. The sodium ion capacitor delivers a maximum energy density of 101.2 Wh kg−1 and a maximum power density of 10,103.7 W kg−1. At 1.0 A g−1, it displays an energy retention of 84.7% after 10,000 cycles.

A bstract We study S-duality of Argyres-Douglas theories obtained by compactification of 6d (2,0) theories of ADE type on a sphere with irregular punctures. The weakly coupled descriptions are given by the degeneration limit of auxiliary Riemann sphere with marked points, among which three punctured sphere represents isolated superconformal theories. We also discuss twisted irregular punctures and their S-duality.

A bstract We use Coulomb branch indices of Argyres-Douglas theories on S 1 × L ( k, 1) to quantize moduli spaces ℳ H of wild/irregular Hitchin systems. In particular, we obtain formulae for the “wild Hitchin characters” — the graded dimensions of the Hilbert spaces from quantization — for four infinite families of ℳ H , giving access to many interesting geometric and topological data of these moduli spaces. We observe that the wild Hitchin characters can always be written as a sum over fixed points in ℳ H under the U(1) Hitchin action, and a limit of them can be identified with matrix elements of the modular transform ST k S in certain two-dimensional chiral algebras. Although naturally fitting into the geometric Langlands program, the appearance of chiral algebras, which was known previously to be associated with Schur operators but not Coulomb branch operators, is somewhat surprising.

Worldwide, 19.3 million new cancer cases and almost 10.0 million cancer deaths occur each year. Recently, much attention has been paid to the ocean, the largest biosphere of the earth that harbors a great many different organisms and natural products, to identify novel drugs and drug candidates to fight against malignant neoplasms. The marine compounds show potent anticancer activity in vitro and in vivo, and relatively few drugs have been approved by the U.S. Food and Drug Administration for the treatment of metastatic malignant lymphoma, breast cancer, or Hodgkin′s disease. This review provides a summary of the anticancer effects and mechanisms of action of selected marine compounds, including cytarabine, eribulin, marizomib, plitidepsin, trabectedin, zalypsis, adcetris, and OKI-179. The future development of anticancer marine drugs requires innovative biochemical biology approaches and introduction of novel therapeutic targets, as well as efficient isolation and synthesis of marine-derived natural compounds and derivatives.

PurposeFire smoke detection in petrochemical plant can prevent fire and ensure production safety and life safety. The purpose of this paper is to solve the problem of missed detection and false detection in flame smoke detection under complex factory background.Design/methodology/approachThis paper presents a flame smoke detection algorithm based on YOLOv5. The target regression loss function (CIoU) is used to improve the missed detection and false detection in target detection and improve the model detection performance. The improved activation function avoids gradient disappearance to maintain high real-time performance of the algorithm. Data enhancement technology is used to enhance the ability of the network to extract features and improve the accuracy of the model for small target detection.FindingsBased on the actual situation of flame smoke, the loss function and activation function of YOLOv5 model are improved. Based on the improved YOLOv5 model, a flame smoke detection algorithm with generalization performance is established. The improved model is compared with SSD and YOLOv4-tiny. The accuracy of the improved YOLOv5 model can reach 99.5%, which achieves a more accurate detection effect on flame smoke. The improved network model is superior to the existing methods in running time and accuracy.Originality/valueAiming at the actual particularity of flame smoke detection, an improved flame smoke detection network model based on YOLOv5 is established. The purpose of optimizing the model is achieved by improving the loss function, and the activation function with stronger nonlinear ability is combined to avoid over-fitting of the network. This method is helpful to improve the problems of missed detection and false detection in flame smoke detection and can be further extended to pedestrian target detection and vehicle running recognition.

Feather waste is the highest protein-containing resource in nature and is poorly reused. Bioconversion is widely accepted as a low-cost and environmentally benign process, but limited by the availability of safe and highly efficient feather degrading bacteria (FDB) for its industrial-scale fermentation. Excessive focuses on keratinase and limited knowledge of other factors have hindered complete understanding of the mechanisms employed by FDB to utilize feathers and feather cycling in the biosphere. Streptomyces sp. SCUT-3 can efficiently degrade feather to products with high amino acid content, useful as a nutrition source for animals, plants and microorganisms. Using multiple omics and other techniques, we reveal how SCUT-3 turns on its feather utilization machinery, including its colonization, reducing agent and protease secretion, peptide/amino acid importation and metabolism, oxygen consumption and iron uptake, spore formation and resuscitation, and so on. This study would shed light on the feather utilization mechanisms of FDBs. Li et a. report a new Streptromyces isolate, SCUT-3 which can efficiently degrade feather into products with high amino acid content, useful as feed for plants, animals and microbes. Using multiple omics and other techniques, they report how SCUT-3 turns on its feather utilization machinery and suggest a number of expressed genes most likely implicated in feather degradation.

This proposal of the “double carbon” goal underscores the pressing need to reduce carbon emissions. To address this issue, the utilization of an optimal scheduling model for an integrated multi-energy complementary system, comprising wind, solar storage, and thermal power generation, is proposed. Two renewable energy generating units, wind and photovoltaic power, cooperate with thermal power units to generate electricity to meet urban base load requirements. Energy storage units compensate for the instability of power generation from renewable energy units. To significantly decrease system carbon emissions, a green certificate trading-carbon emission trading system is introduced. The carbon emission reduction facilitated by the green certificate can offset a portion of the carbon emissions, and the quantities of tradable green certificates and carbon emissions in their respective markets are adjusted accordingly. This model aims to maximize the system’s comprehensive operating earnings while considering the low-carbon economy aspect. The proposed model undergoes simulation analysis, and the results demonstrate its reasonableness and efficacy in terms of carbon reduction and economic viability.