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Copper-catalyzed carboazidation of alkenes with trimethylsilyl azide and cyclic ethers has been achieved. The employment of naturally abundant copper catalysts allowed cyclic ethers to be used as alkylating reagents under oxidative conditions. The use of styrene derivatives and 1,1-diaryl alkenes afforded carboazidation products. In addition, application of five- and six-membered cyclic ethers to the present reaction gave target organic molecules bearing azide and cyclic ether groups with perfect regioselectivity. Radical trapping and clock experiments revealed that the present reaction proceeded via the radical pathway. To further demonstrate the utility of this carboazidation reaction, transformations from the azide group to the related nitrogen-containing compounds were also performed.
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The lead halide perovskite has become a promising candidate for the study of exciton polaritons due to their excellent optical properties. Here, both experimental and simulated results confirm the existence of two kinds of Fabry-Pérot microcavities in a single CsPbBr3 microwire with an isosceles right triangle cross section, and we experimentally demonstrate that confined photons in a straight and a folded Fabry-Pérot microcavity are strongly coupled with excitons to form exciton polaritons. Furthermore, we reveal the polarization characteristic and double-cavity modulation of exciton polaritons emission by polarization-resolved fluorescence spectroscopy. Our results not only prove that the modulation of exciton polaritons emission can occur in this simple double-cavity system but also provide a possibility to develop related polariton devices.
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The present study aimed to evaluate the perinatal outcomes and influencing factors in twin pregnancies undergoing emergency cervical cerclage. The present retrospective cohort study included clinical data that were recorded between January 2015 and December 2021 at The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University (China). The study included data from 103 pregnancies (26 twin and 77 singleton pregnancies) that underwent emergency cerclage and 17 twin pregnancies that underwent expectant treatment. The median gestational age of twin emergency cerclage was significantly lower than that of singleton emergency cerclage, but higher than that of expectant treatment (28.5, 34.0 and 24.0 weeks, respectively). The median interval to delivery of twin emergency cerclage was significantly lower than that of singleton emergency cerclage, but significantly higher than that of expectantly treated twin pregnancies (37.0, 78.0 and 7.0 days, respectively).IMPACT STATEMENTWhat is already known on this subject? An important cause of premature birth is cervical insufficiency. Cervical cerclage extends the gestational period of women with cervical insufficiency. According to 2019 SOGC's No. 373-Cervical Insufficiency and Cervical Cerclage, both twin and single pregnancies benefit from emergency cerclage. However, there is minimal information about the pregnancy outcomes of emergency cerclage in twin pregnancies.What the results of this study add? This study shows that the outcomes of pregnancy in twin pregnancies undergoing emergency cerclage were better than that of expectant treatment but worse than that in singleton pregnancies undergoing emergency cerclage.What the implications are of these findings for clinical practice and/or further research? In this study, pregnant women with cervical insufficiency in twin pregnancies can benefit from emergency cerclage, we should treat those pregnant women as early as possible.
Asunto(s)
Cerclaje Cervical , Nacimiento Prematuro , Incompetencia del Cuello del Útero , Niño , Embarazo , Femenino , Humanos , Estudios Retrospectivos , Resultado del Embarazo , Embarazo Gemelar , Nacimiento Prematuro/epidemiología , Nacimiento Prematuro/etiología , Nacimiento Prematuro/prevención & control , Cerclaje Cervical/métodos , Incompetencia del Cuello del Útero/cirugíaRESUMEN
Background: Thin endometrium is a reproductive disorder that affects embryo implantation. There are several therapies available for this disease, however they are not so effective. Fibroblast growth factor 1 (FGF1) is a member of fibroblast growth factor superfamily (FGFs), and it has been demonstrated that FGF1 expression was altered in samples collected from patients with thin endometrium. However, it is unclear if FGF1 could improve thin endometrium. The aim of this study was to investigate whether FGF1 have a therapeutic effect on thin endometrium. Methods: A model of thin endometrium induced by ethanol was constructed to investigate the effect and mechanism of action of FGF1 in thin endometrium. In the characterization experiments, 6-8 weeks female rats (n = 40) were divided into four groups: i) Control group; ii) Sham group; iii) Injured group; (iv) FGF1 therapy group. Endometrial tissues would be removed after three sexuel cycles after molding. Morphology and histology of the endometrium were evaluated by visual and hematoxylin and eosin staining. Masson staining and expression of α-SMA in endometrium showed the degree of endometrial fibrosis. Western blotting (PCNAãvWF and Vim) and immunohistochemistry (CK19 and MUC-1) demonstrated the effect of FGF1 on cell proliferation and angiogenesis. Moreover, immunohistochemistry (ER and PR) was used to explore the function of endometrium. The remaining rats (n = 36) were divided into three groups: i) Injured group; ii) FGF1 therapy group; and iii) 3-methyladenine. Western blotting (p38ãp-p38ãPI3K ãSQSTM1/p62ãbeclin-1 and LC3) was used to explore the mechanisms of FGF1. Results: In FGF1 therapy group, the morphology and histology of endometrium improved compared with the model group. Masson staining and the expression level of α-SMA showed that FGF1 could decrease the fibrotic area of endometrium. Besides, changes in ER and PR expression in the endometrium suggested that FGF1 could restore endometrium-related functions. Western blotting and immunohistochemistry revealed that PCNA, vWF, Vim, CK19 and MUC-1 were significantly increased after FGF1 treatment compared with the thin endometrium. In addition, Western blotting showed that p38, p-p38, PI3K, SQSTM1/p62, beclin-1 and LC3 levels were higher in FGF1 group than in the injured group. Conclusion: FGF1 application cured the thin endometrium caused by ethanol through autophagy mechanism.
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In this Letter, the palladium/copper-cocatalyzed arylsilylation of internal alkynes with acyl fluorides and silylboranes is described. This is the first example in which acyl fluorides have been utilized for the three-component coupling reaction via decarbonylation, yielding a variety of tetrasubstituted alkenylsilanes in moderate to good yields.
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This paper describes the nickel-catalyzed reductive alkylation of aroyl fluorides with alkyl bromides in a decarbonylative manner. In this reaction, various functional groups are well tolerated and the C(sp2)-C(sp3) bond can be constructed directly without the use of organometallic reagents. The present reaction is a cross-electrophile coupling via the radical pathway, affording the corresponding alkylarenes in moderate to good yields.
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Cavity optomechanical systems operating at the quantum ground state provide a novel way for the ultrasensitive measurement of mass and displacement and provide a new toolbox for emerging quantum information technologies. The high-frequency optomechanical devices could reach the quantum ground state at a high temperature because the access to high frequency is favorable for the cavity optomechanical devices to decouple from the thermal environment. However, reaching ultra-high frequency (THz) is extremely difficult due to the structure of cavity optomechanical devices and properties of materials. In this paper, by introducing acoustic topological interface states, we designed a THz mechanical frequency semiconductor pillar microcavity optomechanical device based on a GaAs/AlAs nanophononic superlattice. In the optomechanical system, multi-optical cavity modes are obtained and the frequency separation between adjacent optical modes is equal to the frequency of the mechanical mode (optomechanical frequency matching). By detuning the laser pump to a lower (higher) energy-resolved sideband to make a spontaneously scattering photon doubly resonate with optical cavity modes at an anti-Stokes (Stokes) frequency and pump frequency, we can achieve an anti-Stokes (Stokes) scattering efficiency 2600 (1800) times larger than that of Stokes (anti-Stokes) scattering, which provides potential for laser cooling and low threshold phonon lasing in the optomechanical system.