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The achievement of dual-functional photocatalytic technology requires a photocatalyst with accelerated charge flow and purposeful active-site arrangement. In this study, we developed an oriented embedding strategy to induce ReS2 growth at the S vacancy in twin-crystal Zn0.5Cd0.5S solid solution (Sv-ZCS), obtaining an atomic-level heterostructure (ReS2/Sv-ZCS). The electronic structure calculations demonstrate that the charge density of the Zn atom around the S vacancy is higher than for other Zn atoms and the introduced S vacancy establishes a high-speed channel for electron transport via formed Zn-S-Re bonds at the interface between ReS2 and Sv-ZCS. Photogenerated electrons and holes gathered on Re atoms and Sv-ZCS, respectively, which achieves spatial charge separation and separated arrangement for redox sites. As a result, the optimized ReS2/Sv-ZCS heterostructure possesses high efficiency of electron injection (2.6-fold) and charge separation (8.44-fold), as well as excellent conductivity capability (20.16-fold). The photocatalytic performance of the ReS2/Sv-ZCS composite exhibits highly improved dual-functional activity with simultaneous H2 evolution and selective oxidation of benzyl alcohol. The reaction rate of benzaldehyde and H2 evolution reaches 125 mmol gcat-1 h-1 and 159 mmol gcat-1 h-1, which is the highest efficiency achieved so far for simultaneous coproduction of H2 fuel and organic chemicals on ReS2-based composites. This work enriches the application of ReS2-modified composites in a dual-functional photoredox system and also gives insight into the role of defects in electronic structure modification and activity improvement.
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Objective: This work is organized to analyze the clinical effects of new shoulder joint abduction frame on the bone metabolic markers, shoulder joint function, and visual analogue scale (VAS) of humeral fracture patients undergoing arthroscopic surgery. Methods: 118 patients with humeral fracture who planned to undergo shoulder surgery in our hospital from November 2018 to June 2021 were selected as the study objects and were divided into two groups according to the random number method, with 59 patients in each group. The patients in the two groups were subjected to arthroscopic shoulder surgery. New shoulder joint abduction frame was used for shoulder joint fixation in the abduction frame group, and sling was used for shoulder joint fixation in the sling group after surgery. The duration of fixation was 4-6 weeks. Finally, the prognostic indicators, complications, and serum bone metabolism levels in 4 and 6 weeks after surgery, shoulder joint function (Neer score), VAS score before surgery and after 3 and 6 months of surgery, and excellent or good rate of shoulder joint activity after 6 months of surgery were compared between the two groups. Results: The postoperative fracture healing time and start time of shoulder joint training were shorter, and the humeral varus angle and femur height loss were smaller in the abduction frame group than in the sling group (P < 0.05). There was no significant difference in the total incidence of complications between the two groups (3.39% and 13.56%, respectively) (P > 0.05). After 4 or 6 weeks of surgery, the levels of serum osteoprotegerin (OPG) and carboxyterminal propeptide of type I procollagen (PICP) were increased but the levels of tartrate-resistant acid phosphatase-5B (TRAP-5B) were decreased in the two groups with more significant differences in the abduction frame group (P < 0.05). After 6 months of follow-up, 2 cases were lost to follow-up in the abduction frame group and 3 cases in the sling group. Neer scores were increased, while VAS scores were decreased in the two groups in the third or sixth months after surgery with significant differences in the abduction frame group (P < 0.05). The excellent or good rate of shoulder joint activity was 94.74% (54/57) in the abduction frame group, significantly higher than that in the sling group (80.36%; 45/56) (P < 0.05). Conclusion: The fixation effect of new shoulder joint abduction frame is significant after arthroscopic surgery, and patients can carry out functional training as early as possible, which is helpful to promote fracture healing, relieve pain, and restore shoulder joint function with high safety.
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Fracturas del Húmero , Fracturas del Hombro , Articulación del Hombro , Humanos , Fracturas del Húmero/cirugía , Fracturas del Hombro/cirugía , Articulación del Hombro/cirugía , Hombro/cirugía , Osteoprotegerina , Artroscopía , Fijación Interna de Fracturas/métodos , Fosfatasa Ácida Tartratorresistente , Resultado del Tratamiento , Estudios RetrospectivosRESUMEN
Objective: To investigate the effect of multimodal analgesia combined with auricular point therapy on physical and mental stress and rehabilitation quality of patients with meniscus injury during the perioperative period. Methods: 148 patients in our hospital from October 2019 to October 2021 who were scheduled to undergo meniscus surgery were selected and grouped according to the order of file establishment, with 74 cases in each. The control group was given routine analgesia, and the observation group was given multimodal analgesia combined with auricular point therapy. The pain level (visual analogue scale (VAS)), physical and mental stress (heart rate (HR), mean arterial pressure (MAP), depression scale (PHQ-9), and anxiety scale (GAD-7)), complications, rehabilitation quality, and analgesia satisfaction were observed. Results: The VAS scores of pain in the observation group were lower than those in the control group at 6 hours before operation and at 6 hours, 24 hours, and 72 hours after operation (P < 0.05). The MAP, HR, PHQ-9, and GAD-7 scores of the observation group were lower than those of the control group 6 hours before operation (P < 0.05). There was no significant difference in MAP, HR, PHQ-9, and GAD-7 scores between the two groups at 6 hours and 24 hours after operation (P > 0.05). The analgesic satisfaction of the observation group was better than that of the control group (P < 0.05). The incidence of complications in the observation group was 8.11% compared with 12.16% in the control group, which was not statistically significant (P > 0.05). The first exhaust, getting out of bed, and hospital stay in the observation group were shorter than those in the control group (P < 0.05). Conclusion: Multimodal analgesia combined with auricular acupuncture therapy is effective in perioperative patients with meniscus injury. It can reduce perioperative pain, reduce physical and mental stress, and promote early postoperative recovery through a variety of analgesic mechanisms.
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Two new dodeca-niobate materials, K3[Nb2O2][H7SiNb12O40]·16H2O (1) and [Cu(en)2]9[(VNb12V1.69Nb0.31O42en0.31)2]·20.69H2O (2) (en = ethylenediamine), have been obtained under hydrothermal conditions and characterized by IR, UV-Vis, XRD, and single crystal X-ray diffraction analysis. Single crystal X-ray analysis reveals that compound 1 presents a reasonable bridging layer structure model and that K plays a great role in the three-dimensional structure. Compound 2 is the first capped Keggin POM with organic ligand chelating the capping atom. The photocatalytic hydrogen evolution and styrene epoxidation catalytic properties of the two compounds were also assessed. Additionally, compound 1 is also a good photocatalyst to degrade RhB.
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Localized surface plasmon resonance (LSPR) offers a valuable opportunity to improve the efficiency of photocatalysts. However, plasmonic enhancement of photoconversion is still limited, as most of metal-semiconductor building blocks depend on LSPR contribution of isolated metal nanoparticles. In this contribution, the concept of collective excitation of embedded metal nanoparticles is demonstrated as an effective strategy to enhance the utilization of plasmonic energy. The contribution of Au-nanochain to the enhancement of photoconversion is 3.5 times increase in comparison with that of conventional isolated Au nanoparticles. Experimental characterization and theoretical simulation show that strongly coupled plasmonic nanostructure of Au-nanochain give rise to highly intensive electromagnetic field. The enhanced strength of electromagnetic field essentially boosts the formation rate of electron-hole pair in semiconductor, and ultimately improves photocatalytic hydrogen evolution activity of semiconductor photocatalysts. The concept of embedded coupled-metal nanostructure represents a promising strategy for the rational design of high-performance photocatalysts.
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The peptidyl nucleoside blasticidin S (BS) produced by Streptomyces griseochromogenes was the first non-mercurial fungicide used to prevent rice blast and increasingly used as a selection reagent in transgenic study. Acylation by addition of a leucine residue at the beta amine group of arginine side chain of demethylblasticidin S (DBS) has been proposed as a novel self-resistance to the cytotoxic biosynthetic intermediate. But the resultant product leucyldemethylblasticidin S (LDBS) has not been isolated as a metabolite, and LDBS synthetase activity remained to be demonstrated in S. griseochromogenes. In this study, we isolated LDBS in a BS heterologous producer S. lividans WJ2 upon the deletion of blsL, which encodes a S-Adenosyl methionine-dependent methyltransferase. Purified BlsL efficiently methylated LDBS at the delta N of beta-arginine to generate the ultimate intermediate LBS, but nearly didn't methylate DBS to final product BS. Above experiments demonstrated that LDBS is indeed an intermediate in BS biosynthetic pathway, and acylation of beta-amino group of arginine side chain is prerequisite for efficient guanidine N-methylation in addition to being a self-resistance mechanism.
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Spatial separation of the reduction center (photosystem I) and oxidation center (photosystem II) is an obvious characteristic of natural photosynthesis. Enlightened by this natural process, a simple material based on silica-sphere-supported Pt nanoparticles (SSP) was designed as a freestanding hydrogen evolution center for semiconductor photocatalysts. In situ photoluminescence characterization showed that the radiation recombination of electron-hole pairs in semiconductors (i.e. TiO2 and CdS) was well suppressed due to the presence of SSP. And the quenching efficiency increases with the hydrogen evolution rate of photocatalysts. These results indicated that SSP could effectively trap electrons from the photoexcited semiconductors during collision between SSP and semiconductor, and then complete the hydrogen evolution reaction over the Pt nanoparticles. Detailed investigation also showed that the performance of SSP was influenced by several factors, including the particle size of the silica sphere and the physical and chemical states of Pt nanoparticles. Besides, it was demonstrated that the loaded metal was not limited to Pt. Pd, Ni and Au can also be used as active sites in this freestanding cocatalyst strategy.
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The activity and stability of CdS for visible-light-driven hydrogen evolution could be significantly enhanced by embedding plasmonic Au nanoparticles. The plasmon resonance energy field of Au nanoparticles could increase the formation rate and lifetime of e(-)/h(+) pairs in CdS semiconductors.
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The peptidyl nucleoside blasticidin S (BS) isolated from Streptomyces griseochromogenes was the first non-mercurial fungicide used on a large scale to prevent rice blast. In the biosynthesis of BS, leucylblasticidin S (LBS) was suggested as the penultimate metabolite with 20-fold less inhibitory activity than the final product BS. Incomplete conversion of LBS to BS at a variable efficiency ranging from 10% to 90% was observed either in the native strain S. griseochromogenes or a heterologous producer Streptomyces lividans WJ2. In this study, we determined that maturation of BS from LBS is not a spontaneous process but is governed by a standalone peptidase PepN, which hydrolyzes LBS in a pH-sensitive way with most appropriate of pH 7~8 but is inactive when the pH is below 5 or above 10. PepN1 and PepN2, two neighboring PepN homologs from Streptomyces lividans were purified in E. coli but displayed ca.100-fold difference in LBS hydrolytic activity. Overexpression of pepN1 in WJ2 enhanced BS yield by 100% and lowered the ratio of LBS to BS from 2:1 to 2:3. This work presents the expansion of the biological role for PepN in antibiotic maturation and the first report of hydrolysis of beta amide linkage by this conserved enzyme.
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Aminopeptidasas/química , Proteínas Bacterianas/química , Streptomyces lividans/enzimología , Aminopeptidasas/aislamiento & purificación , Aminopeptidasas/metabolismo , Proteínas Bacterianas/aislamiento & purificación , Proteínas Bacterianas/metabolismo , Catálisis , Nucleósidos/química , Nucleósidos/metabolismoRESUMEN
A silica-supported CdS nanoparticle photocatalyst exhibits excellent visible-light driven H2 evolution activity without the use of a cocatalyst. The apparent quantum yield can reach 42% under 420 nm light illumination.