45 research outputs found

    Detection of a high-velocity prominence eruption leading to a CME associated with a superflare on the RS CVn-type star V1355 Orionis

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    Stellar coronal mass ejections (CMEs) have recently received much attention for their impacts on exoplanets and stellar evolution. Detecting prominence eruptions, the initial phase of CMEs, as the blue-shifted excess component of Balmer lines is a technique to capture stellar CMEs. However, most of prominence eruptions identified thus far have been slow and less than the surface escape velocity. Therefore, whether these eruptions were developing into CMEs remained unknown. In this study, we conducted simultaneous optical photometric observations with Transiting Exoplanet Survey Satellite and optical spectroscopic observations with the 3.8m Seimei Telescope for the RS CVn-type star V1355 Orionis that frequently produces large-scale superflares. We detected a superflare releasing 7.0×1035erg7.0 \times 10^{35} \: \mathrm{erg}. In the early stage of this flare, a blue-shifted excess component of Hα\mathrm{H \alpha} extending its velocity up to 7601690kms1760-1690 \: \mathrm{km \: s^{-1}} was observed and thought to originate from prominence eruptions. The velocity greatly exceeds the escape velocity (i.e., 350kms1\sim 350 \: \mathrm{km \: s^{-1}}), which provides important evidence that stellar prominence eruptions can develop into CMEs. Furthermore, we found that the prominence is very massive (9.5×1018g<M<1.4×1021g9.5 \times 10^{18} \: \mathrm{g} < M < 1.4 \times 10^{21} \: \mathrm{g}). These data will clarify whether such events follow existing theories and scaling laws on solar flares and CMEs even when the energy scale far exceeds solar cases.Comment: 16 pages, 8 figures. Accepted for publication in The Astrophysical Journa

    Etiler'de Locanda

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    Taha Toros Arşivi, Dosya No: 112-Lokantalarİstanbul Kalkınma Ajansı (TR10/14/YEN/0033) İstanbul Development Agency (TR10/14/YEN/0033

    Impact of hemodialysis on local vessel healing and thrombus formation after drug-eluting stent implantation

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    AbstractBackgroundAlthough hemodialysis (HD) is a suggested risk factor for stent thrombosis, its contribution to local vessel healing after drug-eluting stent (DES) implantation is unclear.MethodsA total of 121 patients (152 lesions treated with DES) who underwent 8-month follow-up coronary angiography with optical coherence tomography (OCT) were enrolled, and the findings were compared between patients with and without HD. To match baseline differences, mid-term OCT findings of 42 propensity score-matched lesions (21 non-HD vs. 21 HD) were compared. Effects of HD on the efficacy of antiplatelet therapy were also evaluated by VerifyNow assay (Accumetrics, San Diego, CA, USA).ResultsPatients with HD had a significantly higher rate of thrombus formation than those without (64% vs. 33%, p=0.007), although the baseline parameters and lesion characteristics differed between the groups. Multivariate logistic regression analysis revealed that HD was associated with an increased risk of thrombus formation (odds ratio 5.991, 95% confidence interval: 1.972–18.199, p=0.002). Even after propensity-matching for patient background and balancing of angiographic and OCT variables, the risk of thrombus formation remained significantly higher in HD patients. The P2Y12-reaction unit was significantly increased after HD (Pre HD: 211±75 vs. Post HD: 262±59, p=0.01), but patients without HD showed no increase during the same elapsed time (221±88 vs. 212±96, p=0.19).ConclusionsHD is a potential risk factor for subclinical thrombus attachment after DES therapy. Systemic problems, such as residual platelet reactivity, associated with HD as well as local vessel features in HD patients might contribute to the increased incidence of thrombus attachment and subsequent onset of thrombotic event after DES implantation

    Simultaneous Integrated Boost Volumetric Modulated Arc Therapy for Middle or Lower Esophageal Cancer Using Elective Nodal Irradiation: Comparison with 3D Conformal Radiotherapy

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    We investigated the feasibility of simultaneous integrated boost (SIB) volumetric modulated arc therapy (VMAT) using elective nodal irradiation (ENI) for middle or lower esophageal cancer and compared it with three-dimensional conformal radiotherapy (3D-CRT). The study included 15 patients. The prescribed doses included a standard dose (50.4 Gy) and a high dose (60 Gy) for the planning target volume (PTV) of the involved lesions. The objective of the whole lung volume receiving ≥ 20 Gy (V20Gy) was 20% reduction in the mean against 3D-CRTs. Our results demonstrate the feasibility of SIB-VMAT for the treatment of middle or lower esophageal cancer with ENI. Although attention should be paid to the low-dose area of the lungs, SIB-VMAT would be a promising treatment option with improved outcomes for esophageal cancer

    An Adult Case of Nasal Chondromesenchymal Hamartoma: Imaging Characteristics Including Diffusion-Weighted Images

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    Nasal chondromesenchymal hamartoma (NCMH), a rare, benign, nasal cavity tumor, typically occurs in children. Differential diagnosis is difficult because NCMH often presents with non-specific findings, including cystic components and invasion of the surrounding area on T2-weighted magnetic resonance images. Here, we present a rare adult case of NCMH, with no clear hyperintensity on diffusion-weighted images (DWI), and bone remodeling on the tumor margins on computed tomography. To the best of our knowledge, this is the first report of DWI on NCMH, and these findings, which suggest benign disease, may be useful in diagnosing NCMH

    Immunohistochemical localization of fatty acid transporters and MCT1 in the sebaceous glands of mouse skin

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    The sebaceous glands secrete sebum to protect the epidermis and hairs by the oily products. The glands express several transporters and binding proteins for the production of fatty acids and uptake of their sources. The present immunohistochemical study examined the expression and localization of CD36, MCT1, FATP4, and E-FABP in the sebaceous glands, including the meibomian and preputial glands of mice. CD36 and MCT1 in sebaceous glands were largely co-localized along the plasma membrane of secretory cells, while they were separately expressed in the glandular portion of meibomian and preputial glands. Immunoreactivities for FATP4 and E-FABP appeared diffusely in the cytoplasm of secretory cells. Genetic deletion of CD36 did not affect the immunolocalization of the three other molecules. The sebaceous glands were judged to be useful for analyzing the functions and relation of fatty acid transporters and binding proteins

    Evaluation of THUNDERBEAT® in open liver resection- a single-center experience

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    Abstract Background THUNDERBEAT® (TB) (Olympus Medical Systems Corp., Tokyo, Japan) is a dynamic energy system device that simultaneously delivers ultrasonically generated frictional heat energy and electrically generated bipolar energy. TB is being routinely used in various operative procedures, however, less is known about its utility in liver resection. We, herein, report our early experience of using TB in open liver resection particularly in patients with normal or near-normal liver parenchyma. Methods We retrospectively reviewed the clinical characteristics, and evaluated the perioperative outcome of twenty-eight patients who underwent liver resection with TB, and twenty-four patients who underwent liver resection with basic procedure in our institution. The resection type was stratified into: major hepatectomy; resection of 3 or more than 3 Couinauds segments, and minor hepatectomy; resection of less than 3 Couinauds segments. Results Liver resection time (mean ± SD) in TB group with major hepatectomy was significantly shorter: 16.7 ± 8.8 compared to 62.8 ± 39.4 min in basic procedure group (P < 0.0001). Accordingly, the liver resection time (mean ± SD) in TB group with minor hepatectomy was also significantly shorter, 8.3 ± 2.9 min compared to 45.2 ± 23.9 min in liver resection with basic procedure (P < 0.001). No significant difference was observed between the groups in terms of intraoperative blood transfusion ratio, postoperative complication and postoperative liver dysfunction. Conclusion TB as a new energy device can offer a safe, reliable and substantially rapid liver resection particularly in patients with normal or near-normal liver parenchyma
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