109 research outputs found

    Diagnostic Value of Transbronchial Needle Aspiration and Endobronchial Ultrasoundguided Transbronchial Needle Aspiration for Hilar and Mediastinal Lymph Nodes in Lung Cancer Patients

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    Background and objective Transbronchial needle aspiration (TBNA) and endobronchial ultrasoundguided TBNA (EBUS-TBNA) have been applied to the diagnosis for mediastinal lymph nodes. The aim of this study is to evaluate the clinical value and safety of TBNA and EBUS-TBNA on hilar and mediastinal lymph nodes of lung cancer patients. Methods Two hundred fifty patients with suspected lung cancer were enrolled. All petients with hilar and/or mediastinal lymphoadenopathy found by CT scan received TBNA, biopsy and brushing. EBUS-TBNA was performed in 15 patients among them. Results Lung cancer were confirmed in 180 patients by TBNA, biopsy and brushing. The positive rates were 82.86%, 51.24% and 45.45%. Fifteen patients after EBUS-TBNA had a positive rate of 91.67%. Conclusion TBNA and EBUS-TBNA were proved to be safe procedure with a high yield for the diagnosis of hilar and mediastinal lymph nodes in lung cancer patients

    Phase diagram of CeFeAs1−x_{1-x}Px_{x}O obtained from electric resistivity, magnetization, and specific heat measurements

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    We performed a systematic study on the properties of CeFeAs1−x_{1-x}Px_{x}O (0≤x≤10\leq x\leq 1) by electrical resistivity, magnetization and specific heat measurements. The c-axis lattice constant decreases significantly with increasing P content, suggesting a remarkable chemical pressure. The Fe-3d electrons show the enhanced metallic behavior upon P-doping and undergo a magnetic quantum phase transition around x≈0.4x \approx 0.4. Meanwhile, the Ce-4f electrons develop a ferromagnetic order near the same doping level. The ferromagnetic order is vanishingly small around x=0.9x=0.9. The data suggest a heavy-fermion-like behavior as x≥0.95x\geq 0.95. No superconductivity is observed down to 2 K. Our results show the ferromagnetic ordered state as an intermediate phase intruding between the antiferromagnetic bad metal and the nonmagnetic heavy fermion metal and support the cerium-containing iron pnictides as a unique layered Kondo lattice system.Comment: 7 pages, 6 figures, text and figures revised, references added

    CeNiAsO: an antiferromagnetic dense Kondo lattice

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    A cerium containing pnictide, CeNiAsO, crystallized in the ZrCuSiAs type structure, has been investigated by measuring transport and magnetic properties, as well as specific heat. We found that CeNiAsO is an antiferromagnetic dense Kondo lattice metallic compound with Kondo scale TK∼T_K \sim 15 K and shows an enhanced Sommerfeld coefficient of γ0∼\gamma_0 \sim 203 mJ/mol⋅\cdotK2^{2}. While no superconductivity can been observed down to 30 mK, Ce ions exhibit two successive antiferromagnetic (AFM) transitions. We propose that the magnetic moment of Ce ion could align in the G type AFM order below the first transition at TN1T_{N1}=9.3 K, and it might be modified into the C type AFM order below a lower transition at TN2T_{N2}=7.3 K. Our results indicate that the 3d−4fd-4f interlayer Kondo interactions play an important role in Ni-based Ce-containing pnictide.Comment: 13 pages, 5 figures, to appear in J. Phys.: Condens. Matte

    Terahertz Sensor via Ultralow-Loss Dispersion-Flattened Polymer Optical Fiber: Design and Analysis

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    A novel cyclic olefin copolymer (COC)-based polymer optical fiber (POF) with a rectangular porous core is designed for terahertz (THz) sensing by the finite element method. The numerical simulations showed an ultrahigh relative sensitivity of 89.73% of the x-polarization mode at a frequency of 1.2 THz and under optimum design conditions. In addition to this, they showed an ultralow confinement loss of 2.18 × 10−12 cm−1, a high birefringence of 1.91 × 10−3, a numerical aperture of 0.33, and an effective mode area of 1.65 × 105 μm2 was obtained for optimum design conditions. Moreover, the range dispersion variation was within 0.7 ± 0.41 ps/THz/cm, with the frequency range of 1.0–1.4 THz. Compared with the traditional sensor, the late-model sensor will have application value in THz sensing and communication

    Discovering Cancer Subtypes via an Accurate Fusion Strategy on Multiple Profile Data

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    Discovering cancer subtypes is useful for guiding clinical treatment of multiple cancers. Progressive profile technologies for tissue have accumulated diverse types of data. Based on these types of expression data, various computational methods have been proposed to predict cancer subtypes. It is crucial to study how to better integrate these multiple profiles of data. In this paper, we collect multiple profiles of data for five cancers on The Cancer Genome Atlas (TCGA). Then, we construct three similarity kernels for all patients of the same cancer by gene expression, miRNA expression and isoform expression data. We also propose a novel unsupervised multiple kernel fusion method, Similarity Kernel Fusion (SKF), in order to integrate three similarity kernels into one combined kernel. Finally, we make use of spectral clustering on the integrated kernel to predict cancer subtypes. In the experimental results, the P-values from the Cox regression model and survival curve analysis can be used to evaluate the performance of predicted subtypes on three datasets. Our kernel fusion method, SKF, has outstanding performance compared with single kernel and other multiple kernel fusion strategies. It demonstrates that our method can accurately identify more accurate subtypes on various kinds of cancers. Our cancer subtype prediction method can identify essential genes and biomarkers for disease diagnosis and prognosis, and we also discuss the possible side effects of therapies and treatment

    Design and optimization of dispersion-flattened microarray-core fiber with ultralow loss for terahertz transmission

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    The paper establishes a late-model of microarray-core based polymer optical fiber with flattened dispersion and ultra-low losses. Its transmission properties are calculated by virtue of the beam propagation approach. From the simulation results, it finds that the modelled fiber has a near-zero dispersion property of 0.29 ± 0.16 ps/THz/cm in a frequency area of 1.05 THz to 1.78 THz, a high birefringence of 1.6 × 10-3, an ultra-low confinement loss of 3.78 × 10-10 dB/m, an effective mode field zone of 4.6 × 105 μm2, and a nonlinear coefficient of 1.2 km-1·W−1. With these good properties, the modelled fiber could be applied for ethanol detection and polarization maintaining THz applications

    Self doping effect and successive magnetic transitions in superconducting Sr2_2VFeAsO3_3

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    We have studied a quinary Fe-based superconductor Sr2_2VFeAsO3_3 by the measurements of x-ray diffraction, x-ray absorption, M\"{o}ssbauer spectrum, resistivity, magnetization and specific heat. This apparently undoped oxyarsenide is shown to be self doped via electron transfer from the V3+^{3+} ions. We observed successive magnetic transitions within the VO2_2 layers: an antiferromagnetic transition at 150 K followed by a weak ferromagnetic transition at 55 K. The spin orderings within the VO2_2 planes are discussed based on mixed valence of V3+^{3+} and V4+^{4+}.Comment: One Table and more references are adde
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