201 research outputs found

    Diagnosis and management of vaginal leiomyoma: A case report and literature review

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    Objectives: Leiomyomas are benign mesenchymal tumors that consist of smooth muscle cells and varying amounts of fibrous stroma. Uterine leiomyomas are the most common, affecting 20% to 30% of reproductive-age women, but vaginal leiomyomas are rare. Treatments gradually diversify with increased awareness of vaginal leiomyoma, but transvaginal fibroid resection remains the commonly used scheme. Case report: Herein, we present the case of a 50-year-old asymptomatic woman who had a mass in the left anterior wall of the vagina discovered by gynecological examination and ultrasound. We used oxytocin diluent injection during surgery to create a water pad in the tissue space and then performed a transvaginal myomectomy. There was little or negligible intraoperative bleeding and no peripheral tissue injury, early or late postoperative complications, incision dehiscence, and no surgical site infection. Conclusions: Transvaginal ultrasonography is the preferred examination for vaginal leiomyomas, and transvaginal myomectomy is the classic treatment method. The formation of a water pad with oxytocin dilution can effectively reduce intraoperative bleeding and shorten surgery time

    Experimental observation of highly anisotropic elastic properties of two-dimensional black arsenic

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    Anisotropic two-dimensional layered materials with low-symmetric lattices have attracted increasing attention due to their unique orientation-dependent mechanical properties. Black arsenic (b-As), with the puckered structure, exhibits extreme in-plane anisotropy in optical, electrical and thermal properties. However, experimental research on mechanical properties of b-As is very rare, although theoretical calculations predicted the exotic elastic properties of b-As, such as anisotropic Young's modulus and negative Poisson's ratio. Herein, experimental observations on highly anisotropic elastic properties of b-As were demonstrated using our developed in situ tensile straining setup based on the effective microelectromechanical system. The cyclic and repeatable load-displacement curves proved that Young's modulus along zigzag direction was ~1.6 times greater than that along armchair direction, while the anisotropic ratio of ultimate strain reached ~2.5, attributed to hinge structure in armchair direction. This study could provide significant insights to design novel anisotropic materials and explore their potential applications in nanomechanics and nanodevices.Comment: 19 pages, 5 figure

    Highly Anisotropic Elastic Properties of Suspended Black Arsenic Nanoribbons

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    Anisotropy, as an exotic degree of freedom, enables us to discover the emergent two-dimensional (2D) layered nanomaterials with low in-plane symmetry and to explore their outstanding properties and promising applications. 2D black arsenic (b-As) with puckered structure has garnered increasing attention these years owing to its extreme anisotropy with respect to the electrical, thermal, and optical properties. However, the investigation on mechanical properties of 2D b-As is still lacking, despite much effort on theoretical simulations. Herein, we report the highly anisotropic elastic properties of suspended b-As nanoribbons via atomic force microscope-based nanoindentation. It was found that the extracted Young's modulus of b-As nanoribbons exhibits remarkable anisotropy, which approximates to 72.2 +- 5.4 and 44.3 +- 1.4 GPa along zigzag and armchair directions, respectively. The anisotropic ratio reaches up to ~ 1.6. We expect that these results could lay a solid foundation for the potential applications of 2D anisotropic nanomaterials in the next-generation nanomechanics and optoelectronics.Comment: 17 pages, 5 figure

    Sensory Features in Affective Analysis: A Study Based on Neural Network Models

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    This study proposes an ensemble model to incorporate sensory features of lexical items in English from external resources into neural affective analysis frameworks. This allows the models to take the combined effects of bi-directional feeling between the sensory lexicon and the writer to infer human affective knowledge. We evaluate our model on two affective analysis tasks. The ensemble model exhibits the best accuracy and the results with 1% F1-score improvement over the baseline LSTM model in the sentiment analysis task. The performance shows that perceptual information can contribute to the performance of sentiment classification tasks significantly. This study also provides a support for the linguistic finding that correlations exist between sensory features and sentiments in the language

    Intralayer Negative Poisson's Ratio in Two-Dimensional Black Arsenic by Strain Engineering

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    Negative Poisson's ratio as the anomalous characteristic generally exists in artificial architectures, such as re-entrant and honeycomb structures. The structures with negative Poisson's ratio have attracted intensive attention due to their unique auxetic effect and many promising applications in shear resistant and energy absorption fields. However, experimental observation of negative Poisson's ratio in natural materials barely happened, although various two-dimensional layered materials are predicted in theory. Herein, we report the anisotropic Raman response and the intrinsic intralayer negative Poisson's ratio of two-dimensional natural black arsenic (b-As) via strain engineering strategy. The results were evident by the detailed Raman spectrum of b-As under uniaxial strain together with density functional theory calculations. It is found that b-As was softer along the armchair than zigzag direction. The anisotropic mechanical features and van der Waals interactions play essential roles in strain-dependent Raman shifts and negative Poisson's ratio in the natural b-As along zigzag direction. This work may shed a light on the mechanical properties and potential applications of two-dimensional puckered materials.Comment: 23 pages, 4 figure

    Epitaxial growth of high quality Mn3SnMn_3Sn thin films by pulsed laser deposition

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    Non-collinear antiferromagnet Weyl semimetal Mn3SnMn_3Sn have attracted great research interest recently. Although large anomalous Hall effect, anomalous Nernst effect and magneto-optical effect have been observed in Mn3SnMn_3Sn, most studies are based on single crystals. So far, it is still challenging to grow high quality epitaxial Mn3SnMn_3Sn thin films with transport and optical properties comparable to their single crystal counterparts. Here, we report the structure, magneto-optical and transport properties of epitaxial Mn3SnMn_3Sn thin films fabricated by pulsed laser deposition (PLD). Highly oriented Mn3+xSn1xMn_{3+x}Sn_{1-x} (0001) and (112ˉ\bar20) epitaxial films are successfully growth on single crystalline Al2O3Al_2O_3 and MgO substrates. Large anomalous Hall effect (AHE) up to ΔRH\left| \Delta R_H\right|=3.02 μΩcm\mu\Omega\cdot cm, and longitudinal magneto-optical Kerr effect (LMOKE) with θK\theta_K = 38.1 mdeg at 633 nm wavelength are measured at 300 K temperature, which are comparable to Mn3SnMn_3Sn single crystals. Our work demonstrates that high quality Mn3SnMn_3Sn epitaxial thin films can be fabricated by PLD, paving the way for future device applications

    p53/p21 Pathway Involved in Mediating Cellular Senescence of Bone Marrow-Derived Mesenchymal Stem Cells from Systemic Lupus Erythematosus Patients

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    Our and other groups have found that bone marrow-derived mesenchymal stem cells (BM-MSCs) from systemic lupus erythematosus (SLE) patients exhibited senescent behavior and are involved in the pathogenesis of SLE. Numerous studies have shown that activation of the p53/p21 pathway inhibits the proliferation of BM-MSCs. The aim of this study was to determine whether p53/p21 pathway is involved in regulating the aging of BM-MSCs from SLE patients and the underlying mechanisms. We further confirmed that BM-MSCs from SLE patients showed characteristics of senescence. The expressions of p53 and p21 were significantly increased, whereas levels of Cyclin E, cyclin-dependent kinase-2, and phosphorylation of retinoblastoma protein were decreased in the BM-MSCs from SLE patients and knockdown of p21 expression reversed the senescent features of BM-MSCs from SLE patients. Our results demonstrated that p53/p21 pathway played an important role in the senescence process of BM-MSCs from SLE

    Endothelial Cells Promote the Colorectal Cancer Stem Cell Phenotype through a Soluble Form of Jagged-1

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    SummaryWe report a paracrine effect whereby endothelial cells (ECs) promote the cancer stem cell (CSC) phenotype of human colorectal cancer (CRC) cells. We showed that, without direct cell-cell contact, ECs secrete factors that promoted the CSC phenotype in CRC cells via Notch activation. In human CRC specimens, CD133 and Notch intracellular domain-positive CRC cells colocalized in perivascular regions. An EC-derived, soluble form of Jagged-1, via ADAM17 proteolytic activity, led to Notch activation in CRC cells in a paracrine manner; these effects were blocked by immunodepletion of Jagged-1 in EC-conditioned medium or blockade of ADAM17 activity. Collectively, ECs play an active role in promoting Notch signaling and the CSC phenotype by secreting soluble Jagged-1
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