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Optically pure sulfoxides are valuable organosulfur compounds extensively employed in medicinal and organic synthesis. In this study, we present a biocatalytic oxidation‐reduction cascade system designed for the preparation of enantiopure sulfoxides. The system involves the cooperation of a low‐enantioselective chimeric oxidase SMO (styrene monooxygenase) with a high‐enantioselective reductase MsrA (methionine sulfoxide reductase A), facilitating "non‐selective oxidation and selective reduction" cycles for prochiral sulfide oxidation. The regeneration of requisite cofactors for MsrA and SMO was achieved via a cascade catalysis process involving three auxiliary enzymes, sustained by cost‐effective D‐glucose. Under the optimal reaction conditions, a series of heteroaryl alkyl, aryl alkyl and dialkyl sulfoxides in R configuration were synthesized through this "one‐pot, one step" cascade reaction. The obtained compounds exhibited high yields of >90 % and demonstrated enantiomeric excess (ee) values exceeding 90 %. This study represents an unconventional and efficient biocatalytic way in utilizing the low‐enantioselective oxidase for the synthesis of enantiopure sulfoxides. [ABSTRACT FROM AUTHOR]

There are many Late Triassic mafic--ultramafic intrusions in the Hongqiling magmatic Ni--Cu sulfide deposit, North-east China. Research on magma evolution leading to formation of these mafic--ultramafic intrusions is of great significance for understanding the mantle beneath Northeast China and associated Ni--Cu mineralization. A trace element study of the No. 1, 3, and 7 intrusions in the Hongqiling deposit reveals that these mafic--ultramafic intrusions are characterized by enrichment of incompatible elements, which however cannot be interpreted by subduction modification. Furthermore, model of batch partial melting of depleted mantle accompanied by upper crustal contamination can simulate the trace element patterns of these mafic--ultramafic intrusions, but partial melting of depleted mantle accompanied by lower crustal contamination model cannot work. In addition, Sr--Nd isotopic compositions of the Hongqiling No. 1, 3, and 7 intrusions also indicate that crustal contamination could have occurred mainly during the magma ascent. Consequently, a possible scenario for the magma evolution is that the primary mafic--ultramafic magma was derived from batch partial melting of a depleted mantle, and then contaminated by Cambrian--Ordovician metamorphic rocks of the Hulan Group during ascent. We conclude that the mantle source contained no significant crustal component in the Late Triassic and was also independent of substantial contribution from subducted material, and therefore the Mesozoic large-scale lithospheric delamination beneath eastern China may happen after a period of time of the Late Triassic.De nombreuses intrusions mafiques--ultramafiques du Trias tardif sont presentes dans le gisement magmatique de sulfures de Ni--Cu de Hongqiling, du nord-est de la Chine. La recherche sur l'evolution du magma ayant mene a la formation de ces intrusions est d'une grande importance pour la comprehension du manteau qui sous-tend le nord-est de la Chine et la mineralisation associee en Ni--Cu. Une etude des elements traces des intrusions no 1, 3 et 7 du gisement de Hongqiling revele qui ces intrusions mafiques--ultramafiques sont caracterisees par un enrichissement en elements incompatibles, qui ne peut toutefois etre interprete comme etant le resultat de la subduction. En outre, un modele de fusion partielle par lot de manteau appauvri accompagnee par une contamination par la croute superieure peut reproduire les distributions d'elements traces de ces intrusions, alors que la fusion partielle de manteau appauvri accompagnee d'une contamination par la croute inferieure n'y arrive pas. La composition des isotopes de Sr et Nd des intrusions no 1, 3 et 7 de Hongqiling indique egalement qu'une contamination crustale pourrait s'etre produite principalement durant l'ascension du magma. Par consequent, un scenario possible pour l'evolution du magma est que le magma mafique--ultramafique primaire est derive de la fusion partielle par lot d'un manteau appauvri et a ensuite ete contamine par des roches metamorphiques cambro--ordoviciennes du Groupe de Hulan durant son ascension. Nous concluons que la source mantellique ne contenait pas de composante crustale significative au Trias tardif et etait independante d'une contribution substantielle de materiel subduit et, donc, que la delamination lithospherique a grande echelle au Mesozoique sous l'est de la Chine pourrait s'etre produite apres un certain temps au Trias tardif. [Traduit par la Redaction], IntroductionNumerous mafic--ultramafic intrusions are exposed in the Hongqiling area, and many of them are ore-bearing intrusions of considerable economic value. Previous studies indicate that these mafic--ultramafic intrusions were emplaced in [...]

Lead contamination in soil has emerged as a significant environmental concern. Recently, pulse electrochemical treatment (PECT) has garnered substantial attention as an effective method for mitigating lead ions in low-permeability soils. However, the impact of varying pulse time gradients, ranging from seconds to hours, under the same pulse duty cycle on lead removal efficiency (LRE) and energy consumption in PECT has not been thoroughly investigated. In this study, a novel, modified PECT method is proposed, which couples PECT with a permeable reaction barrier (PRB) and adds acetic acid to the catholyte. A comprehensive analysis of LRE and energy consumption is conducted by transforming pulse time. The results show that the LREs achieved in these experiments were as follows: PCb-3 s (89.5%), PCb-1 m (91%), PCb-30 m (92.9%), and PCb-6 h (91.9%). Importantly, these experiments resulted in significant reductions in energy consumption, with decreases of 68.5%, 64.9%, 51.8%, and 47.4% compared to constant voltage treatments, respectively. It was observed that LRE improved with an increase in both pulse duration and voltage gradient, albeit with a corresponding rise in energy consumption. The results also revealed that corn straw biochar as a PRB could enhance LRE by 6.1% while adsorbing migrating lead ions. Taken together, the present data highlights the potential of modified PECT technology for remediation of lead-contaminated soil, which provides an optimal approach to achieve high LRE while minimizing energy consumption. [ABSTRACT FROM AUTHOR]

Background: Chimeric antigen receptor-modified T cells (CAR T-cells) have shown exhilarative clinical efficacy for hematological malignancies. However, a shared antigen pool between healthy and malignant T-cells remains a concept to be technically and clinically explored for CAR T-cell therapy in T-cell cancers. No guidelines for engineering CAR T-cells targeting self-expressed antigens are currently available. Method: Based on anti-CD70 CAR (CAR-70) T-cells, we constructed CD70 knock-out and wild-type CAR (CAR-70KO and CAR-70WT) T-cells and evaluated their manufacturing and anti-tumor capability. Single-cell RNA sequencing and TCR sequencing were performed to further reveal the underlying differences between the two groups of CAR T-cells. Results: Our data showed that the disruption of target genes in T-cells before CAR transduction advantaged the expansion and cell viability of CAR T-cells during manufacturing periods, as well as the degranulation, anti-tumor efficacy, and proliferation potency in response to tumor cells. Meanwhile, more naïve and central memory phenotype CAR+ T-cells, with higher TCR clonal diversity, remained in the final products in KO samples. Gene expression profiles revealed a higher activation and exhaustion level of CAR-70WT T-cells, while signaling transduction pathway analysis identified a higher level of the phosphorylation-related pathway in CAR-70KO T-cells. Conclusion: This study evidenced that CD70 stimulation during manufacturing process induced early exhaustion of CAR-70 T-cells. Knocking-out CD70 in T-cells prevented the exhaustion and led to a better-quality CAR-70 T-cell product. Our research will contribute to good engineering CAR T-cells targeting self-expressed antigens. [ABSTRACT FROM AUTHOR]

Currently, as shown by large-scale research on two-dimensional materials in the field of nanoelectronics and catalysis, the construction of large-area two-dimensional materials is crucial for the development of devices and their application in photovoltaics, sensing, optoelectronics, and energy generation/storage. Here, using atmospheric-pressure chemical vapor deposition, we developed a method to regulate growth conditions according to the growth mechanism for WSe2 and MoSe2 materials. By accurately controlling the hydrogen flux within the range of 1 sccm and the distance between the precursor and the substrate, we obtained large-size films of single atomic layers with thicknesses of only about 1 nm. When growing the samples, we could not only obtain a 100 percent proportion of samples with the same shape, but the samples could also be glued into pieces of 700 μm and above in size, changing the shape and making it possible to reach the millimeter/submillimeter level visible to the naked eye. Our method is an effective method for the growth of large-area films with universal applicability. [ABSTRACT FROM AUTHOR]

Black soils are vital agricultural resources, and assessing heavy metal contamination in black soils is of great significance to the sustainable development of agriculture and the environment. In this study, 1246 surface soil samples were collected from the central-eastern part of Changchun, where phaeozems and chernozems are widely distributed, and the As, Hg, Cr, Cd, and Pb concentrations were determined to investigate the pollution status in the black soils by the geoaccumulation index (Igeo). To eliminate the influence of background variation and improve the calculation accuracy of the Igeo values, the local background values of these five elements were estimated after classifying the samples into three clusters with the k-means clustering method. The Igeo calculated with the local background values not only identified the pollution that is difficult to recognize in the low-background areas but also eliminated the easily misidentified pollution in the high-background areas. The Igeo results show that the black soils are mainly contaminated with Hg, followed by Cd and Pb, and are almost free from the pollution of As and Cr. The further the sampling sites are from urban areas, the milder the soil pollution is. A positive matrix factorization (PMF) analysis shows that industrial activities and coal burning contributed the most to the heavy metal pollution in the black soils, followed by agricultural activities, which should be paid more attention to. [ABSTRACT FROM AUTHOR]

The huge annual output of coal fly ash is harmful to the environment, but it is widely used because of its good adsorption potential. In this study, using coal fly ash as a raw material and sodium hydroxide as an activator, a novel adsorbent was synthesized at 300 °C and used to adsorb low concentrations of ammonia nitrogen from water. In this study, scanning electron microscopy, X-ray diffraction analysis, Fourier transform infrared spectroscopy, energy dispersive X-ray spectroscopy, and a surface area and porosity analyzer were used to analyze the adsorbent's physicochemical properties. The results showed that after alkali modification, the activity of the adsorbent had greatly enhanced. The impacts of solution pH, adsorbent dosage, adsorption time, and initial concentration of ammonia nitrogen on the adsorption capacity and removal efficiency were evaluated through a series of adsorption experiments. Moreover, the adsorption data were better fitted to the pseudo-second-order kinetic model and Langmuir model, indicating that the adsorption process was mainly chemical adsorption and monolayer uniform adsorption. As a result, the new adsorbent is inexpensive and effective, and it could be used to remove low-concentration ammonia nitrogen from water with a maximum removal efficiency of approximately 89%. [ABSTRACT FROM AUTHOR]

The rational utilization of solid waste has always been a worldwide concern. In this study, coal fly ash (CFA) and red mud (RM) were used in combination to synthesize efficient heavy metal adsorbents. A new way of resource recycling was provided with the collaborative reuse of CFA and RM. To obtain the modified composite materials, CFA and RM were mixed and melted in three ratios. After modification, these materials were then utilized to adsorb Pb, Cu, and Cd in water in both single and ternary systems. The physicochemical properties of CFA, RM, and three modified composite materials were measured by X-ray diffraction analysis, energy dispersive X-ray spectroscopy, scanning electron microscope, Fourier transform infrared spectroscopy, vibrating sample magnetometer, surface area analyzer, and porosity analyzer. In the single and ternary systems, the effects of the modified composite material dosage, solution pH, initial concentration of heavy metals, and adsorption time were discussed, and the results were better fitted with the Langmuir isotherm and the pseudo-second-order kinetic. It was discovered that the modified composite materials had a greater specific surface area (63.83 m2/g) than CFA and RM alone, as well as superior adsorption capacity and magnetic characteristics. The adsorption capacities of C1R4 for Pb, Cu, and Cd were 149.81 mg/g, 135.96 mg/g, and 127.82 mg/g in the single system, while those of Cu and Cd decreased slightly in the ternary system, and the preferential adsorption order of the modified composite materials for heavy metal ions was Pb > Cu > Cd. Among the three modified composite materials, C1R4 had the best adsorption capacity. [ABSTRACT FROM AUTHOR]

Multispectral photodetectors are promising devices capable of detecting photons in a broad range of multiple wavelengths, which have gained considerable potential in biomedical imaging, surveillance, and other emerging artificial intelligence applications. Different light signals acquired with these photodetectors are useful in effective object recognition and navigations due to the extraction of redundant light information. However, these capabilities are obstructed by the circuitry complexity and unwanted electrical cross‐talk arising from the combination of multiple absorbers and structures. Herein, a confined assembly method by the synergy of solvent engineering for controlling organic ITIC 1D arrays in different crystallinity is proposed. Organic array‐based photodetectors present a multispectral optoelectronic performance with the maximum responsivities of 26.0, 17.6, 174.9, and 60.0 mA W−1, corresponding to different wavelength lights. Based on the large‐area fabrication of ITIC array‐based photodetectors, multispectral image sensors with high accuracy are obtained for capturing the different light signals of capital letters "T," "I," "P," and "C." Furthermore, the integration of the devices into functional optoelectronic circuits have been demonstrated as signal intermediary for optical and electrical data disposal, which open up new opportunities for the integration of organic semiconductors toward the multispectral functional optoelectronic modules. [ABSTRACT FROM AUTHOR]

To explore the existing characteristics of nitrogen and phosphorus in the main rivers of Changchun City, the overlying water and sediment were sampled and tested. The results showed that the spatial distribution of nitrogen and phosphorus contents in overlying water and sediment was diverse. In overlying water, nitrogen and phosphorus contents in the north and west of Changchun were high, while their contents in the south were low. In the sediment, their contents were high in the south and west and low in the north. The pollution of nitrogen and phosphorus was serious in most rivers. Xinkai River, Chuan Lake, and West Lake had the acutest pollution of ammonia, total nitrogen, and total phosphorus, and their contamination degree in Yongchun River was the lowest. In terms of time, with the government actively carrying out river management, the pollution control of ammonia and phosphorus has achieved remarkable results. The pollution of nitrogen and phosphorus was closely related to the quality of the water environment, and the phosphorus content in overlying water and sediment had the strongest correlation with other water quality parameters. Moreover, the change in chemical oxygen demand could be predicted by the partial least squares method on the basis of its high correlation with nitrogen and phosphorus in overlying water. This study provides a scientific reference for the investigation and treatment of nitrogen and phosphorus pollution in surface water of typical old industrial cities in China. [ABSTRACT FROM AUTHOR]

With the development of global economic integration and the gradual formation of unified tourism markets, strengthening regional tourism cooperation has become an internal requirement of regional tourism development but also a new way of sustainably developing tourism. This study selected the key factors affecting the cooperation of tourist attractions, including the competitiveness of tourist attractions and the relationships among tourist attractions, and established an evaluation index system and mathematical model of tourist attractions' cooperation. Furthermore, the level of cooperation was evaluated. According to the value of the cooperation level, the spatial characteristics of the cooperation level were analyzed using a geographic information systems analytical method, which can better reflect the competitiveness, relationships, and overall cooperation level of tourist attractions. The results showed that the tourism competitiveness of tourist attractions was generally strong and their internal relations relatively close, and the overall tourism cooperation level was high. However, a two-dimensional four-quadrant map revealed that there were still great differences in tourism competitiveness among tourist attractions and their internal relations. Twenty-three tourist attractions exhibited weak tourism competitiveness and sparse relationships with other tourist attractions. The tourism competitiveness of tourist attractions and their internal relations and tourism cooperation level showed positive spatial autocorrelation and spatial agglomeration characteristics. The spatial differentiation of an "inverted U-shape" indicated that the cooperation level, tourism competitiveness, and mutual relations of tourist attractions were not balanced and that a stable and gradual spatial transformation had not been achieved. This study can provide valuable insights for the government to formulate policies and measures for regional tourism cooperation, carry out regional joint marketing, and help tourism enterprises design tourist routes. [ABSTRACT FROM AUTHOR]

This study collected 1135 topsoil samples of cultivated land in Laiyang County, eastern China, to analyze the distribution, pollution and health risks of heavy metals (As, Cd, Cu, Cr, Hg, Ni, Pb and Zn). The results show that: (1) the levels of eight heavy metals at some sites were higher than the risk screening values in China, and there was heavy metal pollution. (2) An improved geoaccumulation index was used to evaluate soil pollution. The average value of Igeo before and after improvement was 0.32 (Iml, no pollution to medium pollution) and −0.04 (Iol, no pollution), respectively. (3) Hg and Cd were identified as the main contributors to ecological risk in this study, with a cumulative ecological risk contribution percentage > 65%. The results of the potential ecological risk index (PERI) show that 9.3% of the sampling sites were considered to have moderate ecological risk. (4) As, Pb, Ni and Cu made a contribution of >95% in terms of non-carcinogenic risk to adults and children through different exposure routes, and different soil intake routes posed no non-carcinogenic risk to adults; there was a sampling site with HQChildren > 1, which was consistent with the non-carcinogenic risk site, indicating that children in this location and surrounding areas are more likely to face dual health risks. Therefore, it is necessary to promote the risk management of heavy metals in the study area in order to safely use soil resources. [ABSTRACT FROM AUTHOR]