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Herein, we describe an efficient method for the synthesis of alkenylphosphine oxides via a Tf2O promoted addition-elimination process. Various diarylphosphine oxides and alkylarylphosphine oxides react with ketones smoothly and produce alkenylphosphine oxides in moderate to excellent yields with abundant functional group compatibility. In addition, several transformations and applications of the product also demonstrate the potential value of the methodology.
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It is a promising research direction to develop catalysts with high stability and ozone utilization for low-temperature ozone catalytic oxidation of VOCs. While bimetallic catalysts exhibit excellent catalytic activity compared with conventional single noble metal catalysts, limited success has been achieved in the influence of the bimetallic effect on the stability and ozone utilization of metal catalysts. Herein, it is necessary to systematically study the enhancement effect in the ozone catalytic reaction induced by the second metal. With a simple continuous impregnation method, a platinum-cerium bimetallic catalyst is prepared. Also highlighted are studies from several aspects of the contribution of the second metal (Ce) to the stability and ozone utilization of the catalysts, including the "electronic effect" and "geometric effect". The synergistic removal rate of toluene and ozone is nearly 100% at 30 °C, and it still shows positive stability after high humidity and a long reaction time. More importantly, the instructive significance, which is the in-depth knowledge of enhanced catalytic mechanism of bimetallic catalysts resulting from a second metal, is provided by this work.
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Cerio , Ozono , Oxidación-Reducción , Metales , CatálisisRESUMEN
BACKGROUND: Blepharoptosis may result in an unattractive appearance and vision problems. According to the severity of ptosis, patients may undergo correction surgery using upper eyelid retractors. The conventional incision for surgical procedures was the double-eyelid incision, potentially resulting in an obvious and unnatural scar or long-lasting edema and prolonged recovery time. OBJECTIVES: The aim of this study was to introduce a supraciliary incision as an alternative to the double-eyelid incision for blepharoptosis correction that creates a scarless, natural appearance with a quick recovery time. METHODS: From June 2019 to June 2021, 32 patients (36 eyelids) underwent blepharoptosis correction through a supraciliary incision. MRD1, the height of the eyelid fissure, and the patient's satisfaction with the shape and scar as well as postoperative complications (eyelid insufficiency, conjunctival prolapse, inadequate correction of ptosis, and excessive correction of ptosis). RESULTS: All 32 patients (36 eyelids) were followed up for 6 to 18 months, with an average follow-up of 11.6 months. The postoperative satisfaction rate was 96.43%. There was no overcorrection, but one patient (1 eyelid, 2.8%) was under correction that required secondary correction. One patient (1 eyelid, 2.8%) experienced conjunctival prolapse. Sixteen patients showed lagophthalmos early after surgery, in which one patient experienced early-stage keratitis and completely recovered within two months. CONCLUSION: Blepharoptosis correction via supraciliary incision allows for broader indications and fewer surgical scars without disrupting eyelid integrity, resulting in quick recovery after surgery. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
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Blefaroplastia , Blefaroptosis , Humanos , Pueblo Asiatico , Blefaroplastia/métodos , Blefaroptosis/cirugía , Cicatriz/cirugía , Estudios de Cohortes , Estética , Satisfacción del Paciente , Estudios Retrospectivos , Resultado del Tratamiento , Complicaciones PosoperatoriasRESUMEN
Waste resource utilization of petroleum coke is crucial for achieving global carbon emission reduction. Herein, a series of N-doped microporous carbons were fabricated from petroleum coke using a one-pot synthesis method. The as-prepared samples had a large specific surface area (up to 2512 m2/g), a moderate-high N content (up to 4.82 at.%), and high population (55%) of ultra-micropores (<0.7 nm). Regulating the N content and ultra-microporosity led to efficient CO2 adsorption and separation. At ambient pressure, the optimal N-doped petroleum coke-based microporous carbon exhibited the highest CO2 uptake of 4.25 mmol/g at 25°C and 6.57 mmol/g at 0°C. These values are comparable or even better than those of numerous previously reported adsorbents prepared by multistep synthesis, primarily due to the existence of ultra-micropores. The sample exhibited excellent CO2/N2 selectivity at 25°C owing to the abundant basic pyridinic and pyrrolic N species; and showed superior CO2 adsorption-desorption cycling performance, which was maintained at 97% after 10 cycles at 25°C. Moreover, petroleum coke-based microporous carbon, with a considerably high specific surface area and hierarchical pore structure, exhibited excellent electrochemical performance over the N-doped sample, maintaining a favorable specific capacitance of 233.25 F/g at 0.5 A/g in 6 mol/L KOH aqueous electrolyte. This study provides insight into the influence of N-doping on the porous properties of petroleum coke-based carbon. Furthermore, the as-prepared carbons were found to be promising adsorbents for CO2 adsorption, CO2/N2 separation and electrochemical application.
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Carbono , Coque , Carbono/química , Dióxido de Carbono/química , Adsorción , PorosidadRESUMEN
The application of small-pore chabazite-type SSZ-13 zeolites, key materials for the reduction of nitrogen oxides (NOx) in automotive exhausts and the selective conversion of methane, is limited by the use of expensive N,N,N-trimethyl-1-ammonium adamantine hydroxide (TMAdaOH) as an organic structure-directing agent (OSDA) during hydrothermal synthesis. Here, we report an economical and sustainable route for SSZ-13 synthesis by recycling and reusing the OSDA-containing waste liquids. The TMAdaOH concentration in waste liquids, determined by a bromocresol green colorimetric method, was found to be a key factor for SSZ-13 crystallization. The SSZ-13 zeolite synthesized under optimized conditions demonstrates similar physicochemical properties (surface area, porosity, crystallinity, Si/Al ratio, etc.) as that of the conventional synthetic approach. We then used the waste liquid-derived SSZ-13 as the parent zeolite to synthesize Cu ion-exchanged SSZ-13 (i.e., Cu-SSZ-13) for ammonia-mediated selective catalytic reduction of NOx (NH3-SCR) and observed a higher activity as well as better hydrothermal stability than Cu-SSZ-13 by conventional synthesis. In situ infrared and ultraviolet-visible spectroscopy investigations revealed that the superior NH3-SCR performance of waste liquid-derived Cu-SSZ-13 results from a higher density of Cu2+ sites coordinated to paired Al centers on the zeolite framework. The technoeconomic analysis highlights that recycling OSDA-containing waste liquids could reduce the raw material cost of SSZ-13 synthesis by 49.4% (mainly because of the higher utilization efficiency of TMAdaOH) and, meanwhile, the discharging of wastewater by 45.7%.
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Zeolitas , Zeolitas/química , Oxidación-Reducción , Amoníaco/química , Óxidos de Nitrógeno/químicaRESUMEN
Immunogenicity is a major issue associated with the PK, efficacy, and safety evaluation of therapeutic protein products during pre-clinical and clinical studies. A multi-tiered approach consisting of screening, confirmatory, and titration assays has been widely adopted for anti-drug antibody testing. GQ1001, a recombinant humanized anti-human epidermal growth factor receptor 2 monoclonal antibody covalently linked to a cytotoxin of DM1, possesses a novel format of antibody-drug conjugates. In this study, we reported the development, validation, and application of an acid-dissociation bridging enzyme-linked immunosorbent assay for the detection of antibodies against GQ1001 in cynomolgus monkey serum. The sensitivity of the screening assay was 126.141 ng/mL in undiluted serum. The screening assay and confirmatory assay were neither affected by the naïve monkey serum nor by 2% and 5% (v/v) erythrocyte hemolysates. Moreover, the assay was not subject to interference by 2500 ng/mL of human IgG1 in the samples. Drug interference at low positive control (150 ng/mL) and high positive control (8000 ng/mL) of anti-GQ1001 antibodies was not observed when GQ1001 concentrations were below 3.125 µg/mL and 100 µg/mL, respectively. Furthermore, no hook effect was observed for the positive antibodies in the concentration range of 8 to 64 µg/mL. The validated assay was, thereafter, successfully applied to a single-dose toxicity study of GQ1001. Anti-drug antibody positive rates among dosing animals and testing samples were reported, and no significant impact was found on toxicokinetic outcomes.
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Anticuerpos Monoclonales , Inmunoconjugados , Animales , Macaca fascicularis , Ensayo de Inmunoadsorción Enzimática , SueroRESUMEN
In recent years, methyl formate has received considerable attention as an ideal and green C1 building block to synthesize carboxylic esters. However, examples of a one-step route to esters with one-carbon elongation using methyl formate as a source of methoxycarbonyl radical are still rare. Herein, we present peroxide-induced radical carbonylation of N-(2-methylallyl)benzamides with methyl formate as the precursor of methoxycarbonyl radical and RuCl3 as catalyst, affording a series of biologically valuable 4-[(methoxycarbonyl)methyl]-3,4-dihydroisoquinolinones with good tolerance and insensitivity to moisture in one pot under simple and mild conditions.
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Alquenos , Formiatos , Catálisis , Esterificación , ÉsteresRESUMEN
Tf2 O mediated intermolecular / intramolecular [2+2+2] cycloaddition between alkynes and nitriles has been developed for efficient construction of polysubstituted pyrimidines and bicyclopyrimidines. In presence of Tf2 O, aza-allene species were generated inâ situ through nitrile activation and subsequently participated in the [2+2+2] cycloaddition, which was fully supported by deuteration experiments. The reaction had good substrate extensibility with moderate to excellent yield including trimethylsilylalkynes. The method was utilized as a synthetic tool in the preparation of a luminescent metal complex.
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Nitrilos , Pirimidinas , Reacción de Cicloadición , Estructura Molecular , EstereoisomerismoRESUMEN
Numerous studies indicated the physical benefits of regular exercise, but the neurophysiological mechanisms of regular exercise in elders were less investigated. We aimed to compare changes in brain activity during exercise in elderly people and in young adults with and without regular exercise habits. A total of 36 healthy young adults (M/F:18/18) and 35 healthy elderly adults (M/F:20/15) participated in this study. According to exercise habits, each age group were classified into regular and occasional exerciser groups. ECG, EEG, and EMG signals were recorded using V-AMP with a 1-kHz sampling rate. The participants were instructed to perform three 5-min bicycle rides with different exercise loads. The EEG spectral power of elders who exercised regularly revealed the strongest positive correlation with their exercise intensity by using Pearson correlation analysis. The results demonstrate that exercise-induced significant cortical activation in the elderly participants who exercised regularly, and most of the p-values are less than 0.001. No significant correlation was observed between spectral power and exercise intensity in the elders who exercised occasionally. The young participants who exercised regularly had greater cardiac and neurobiological efficiency. Our results may provide a new exercise therapy reference for adult groups with different exercise habits, especially for the elders.
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Ejercicio Físico , Hábitos , Anciano , Estado de Salud , Humanos , Adulto JovenRESUMEN
A method for the regio- and stereoselective synthesis of highly substituted vinyl ethers via trans-1,2-difunctionalization of alkynes with a cyclic λ3-iodane electrophile (benziodoxole triflate) and alcohols is reported. The reaction tolerates a variety of internal and terminal alkynes as well as various alcohols, affording ß-λ3-iodanyl vinyl ethers in good yields with high regio- and stereoselectivities. The benziodoxole moiety of the products can be used as a versatile linchpin for the synthesis of structurally diverse vinyl ethers that are difficult to access by other means.
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We report herein the synthesis of highly substituted and stereochemically well-defined vinylbenziodoxole (VBX) derivatives through hydrochlorination and iodochlorination of ethynylbenziodoxoles. The hydrochlorination is achieved using pyridine hydrochloride as an HCl source in an anti-fashion under mild, open-air conditions to afford a 2-chlorinated VBX product, which serves as a useful building block for the stereoselective synthesis of trisubstituted alkenes. Meanwhile, iodochlorination with iodine monochloride proceeds in an unusual syn-pathway, stereoselectively affording a tetrasubstituted VBX derivative.
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Herein, we reported the synthesis of well-defined Co3O4 nanoarrays (NAs) supported on a monolithic three-dimensional macroporous nickel (Ni) foam substrate for use in high-efficiency CO oxidation. The monolithic Co3O4 NAs catalysts were obtained through a generic hydrothermal synthesis route with subsequent calcination. By controlling the reaction time, solvent polarity and deposition agent, these Co3O4 NAs catalysts exhibited various novel morphologies (single or hybrid arrays), whose physicochemical properties were further characterized by using several analytical techniques. Based on the catalytic and characterization analyses, it was found that the Co3O4 NAs-6 catalyst with nanobrush and nanomace arrays displayed enhanced catalytic activity for CO oxidation, achieving an efficient 100% CO oxidation conversion at a gas hourly space velocity (GHSV) 10,000hr-1 and 150°C with long-term stability. Compared with the other Co3O4 NAs catalysts, it had the highest abundance of surface-adsorbed oxygen species, excellent low-temperature reducibility and was rich in surface-active sites (Co3+/Co2+=1.26).
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Monóxido de Carbono/química , Cobalto/química , Modelos Químicos , Níquel/química , Óxidos/química , Adsorción , Oxidación-ReducciónRESUMEN
BACKGROUND: Our article describes our experience with using a frontal axial pattern flap combined with hard palate mucosa transplant to reconstruct midfacial defects after the excision of huge basal cell carcinoma. METHODS: We retrospectively reviewed four patients diagnosed with midface huge basal cell carcinoma through biopsy between 2014 and 2016. Both the eyelid and nose were involved in all the patients. All the patients underwent the studied surgical method and were followed up from 12 to 36 months. RESULTS: All the patients preserved good eyelid function and relatively good esthetic satisfaction. No basal cell carcinoma recurred. CONCLUSIONS: This combined surgical procedure is a good method for reconstructing defects after the excision of huge basal cell carcinomas in the midface.
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Carcinoma Basocelular/cirugía , Neoplasias de Cabeza y Cuello/cirugía , Mucosa Bucal/trasplante , Procedimientos de Cirugía Plástica/métodos , Neoplasias Cutáneas/cirugía , Colgajos Quirúrgicos , Anciano , Anciano de 80 o más Años , Neoplasias de los Párpados/cirugía , Cara/cirugía , Femenino , Humanos , Masculino , Recurrencia Local de Neoplasia , Neoplasias Nasales/cirugía , Paladar Duro/trasplante , Pronóstico , Estudios Retrospectivos , Herida Quirúrgica/cirugíaRESUMEN
A modified Hummer's method was adopted for the synthesis of graphene oxide (GO) and reduced graphene oxide (rGO). It was revealed that the modified method is effective for the production of GO and rGO from graphite. Transmission electron microscopy (TEM) images of GO and rGO showed a sheet-like morphology. Because of the presence of oxygenated functional groups on the carbon surface, the interlayer spacing of the prepared GO was higher than that of rGO. The presence of OH and CO groups in the Fourier transform infrared spectra (FTIR) spectrum and G-mode and 2D-mode in Raman spectra confirmed the synthesis of GO and rGO. rGO (292.6m2/g) showed higher surface area than that of GO (236.4m2/g). The prepared rGO was used as an adsorbent for benzene and toluene (model pollutants of volatile organic compounds (VOCs)) under dynamic adsorption/desorption conditions. rGO showed higher adsorption capacity and breakthrough times than GO. The adsorption capacity of rGO for benzene and toluene was 276.4 and 304.4mg/g, respectively. Desorption experiments showed that the spent rGO can be successfully regenerated by heating at 150.0°C. Its excellent adsorption/desorption performance for benzene and toluene makes rGO a potential adsorbent for VOC adsorption.
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Grafito/química , Modelos Químicos , Compuestos Orgánicos Volátiles/química , Adsorción , Grafito/análisis , Compuestos Orgánicos Volátiles/análisisRESUMEN
A PdII -catalyzed 2:1 coupling reaction of alkynylbenziodoxole with carboxylic acid to afford (alk-1-en-3-ynyl)benziodoxole, which is efficiently promoted by an octahydrophenazine ligand, is reported. The reaction involves a Pd-assisted 1,2-iodine(III) shift of the alkynylbenziodoxole followed by stereoselective introduction of carboxy and alkynyl groups (the latter originating from another molecule of the alkynylbenziodoxole) into the 1-position of the transient Pd-vinylidene species. The product of this 1,1-carboxyalkynylation reaction serves as a new functionalized enyne-type building block for further synthetic transformations.
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Alkynyl-λ(3)-iodanes have been established as alkynyl cation equivalents for the alkynylation of carbon- and heteroatom-based nucleophiles. Herein, we report an unprecedented reaction mode of this compound class, which features a Pd(II)-assisted 1,2-I(III) shift of an alkynylbenziodoxole. A Pd(II) catalyst mediates this shift and the subsequent interception of the transient vinylidene species with carboxylic acid (1,1-hydrocarboxylation). The product of this stereoselective rearrangement-addition reaction, ß-oxyalkenylbenziodoxole, represents a novel and useful building block for further synthetic transformations.
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While transition metal catalyzed addition reactions of arylmetal reagents to unfunctionalized alkynes have been extensively developed in the last decade, analogous reactions using alkenylmetal reagents remain rare regardless of their potential utility for the synthesis of unsymmetrical 1,3-dienes. Reported herein is the development of a cobalt/diphosphine catalyst which promotes efficient and stereoselective addition of alkenylzinc reagents to unfunctionalized internal alkynes. The resulting dienylzinc species serve as versatile intermediates for further synthetic transformations.
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A modified method based on existing static facial sling techniques to reconstruct the corner of mouth for elder facial palsy was developed and reported. According to the anatomy and function of the zygomatic minor and zygomatic major, this technique uses nasolabial dermis as a whole to attach to the orbicularis oris to provide attachment to the whole area. Therefore, in our method, the function of the zygomaticus minor and zygomaticus major were reconstructed by attaching to the zygomatic arch periosteum through such slings. This procedure is effective in improving facial symmetry and obtaining inconspicuous scarring. We believe that our technique is a simple, effective and reliable option for elder facial paralysis.
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Parálisis Facial/cirugía , Surco Nasolabial/cirugía , Colgajos Quirúrgicos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Procedimientos de Cirugía PlásticaRESUMEN
Mild and regiocontrolled synthesis of a multisubstituted furan is achieved through Pd(OAc)2 -catalyzed room-temperature condensation of an alkynylbenziodoxole, a carboxylic acid, and an enolizable ketimine, which contribute to C1, CO, and C2 fragments, respectively, to the furan skeleton. The reaction tolerates a broad range of functional groups in each of the reaction components, and enables highly modular and flexible synthesis of variously substituted furans. The reaction is particularly effective for the rapid generation of tri- and tetraarylfurans and furan-containing oligoarylenes without relying on conventional cross-coupling chemistry.