234 research outputs found

    Ground-state properties of neutron-rich Mg isotopes

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    We analyze recently-measured total reaction cross sections for 24-38Mg isotopes incident on 12C targets at 240 MeV/nucleon by using the folding model and antisymmetrized molecular dynamics(AMD). The folding model well reproduces the measured reaction cross sections, when the projectile densities are evaluated by the deformed Woods-Saxon (def-WS) model with AMD deformation. Matter radii of 24-38Mg are then deduced from the measured reaction cross sections by fine-tuning the parameters of the def-WS model. The deduced matter radii are largely enhanced by nuclear deformation. Fully-microscopic AMD calculations with no free parameter well reproduce the deduced matter radii for 24-36Mg, but still considerably underestimate them for 37,38Mg. The large matter radii suggest that 37,38Mg are candidates for deformed halo nucleus. AMD also reproduces other existing measured ground-state properties (spin-parity, total binding energy, and one-neutron separation energy) of Mg isotopes. Neutron-number (N) dependence of deformation parameter is predicted by AMD. Large deformation is seen from 31Mg with N = 19 to a drip-line nucleus 40Mg with N = 28, indicating that both the N = 20 and 28 magicities disappear. N dependence of neutron skin thickness is also predicted by AMD.Comment: 15 pages, 13 figures, to be published in Phys. Rev.

    A Transponder Aggregator with Efficient Use of Filtering Function for Transponder Noise Suppression

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    Colorless, directionless, and contentionless reconfigurable optical add/drop multiplexing (CDC-ROADM) provides highly flexible physical layer network configuration. Such CDC-ROADM must operate in multiple wavelength bands which are being increasingly implemented in optical transmission systems. The operation in C+L bands requires switch devices used in CDC-ROADM to also be capable of multiband operation. Recent studies on wavelength division multiplexing (WDM) systems have pointed out the impact of amplified spontaneous emission (ASE) noise generated by signals of different wavelengths, which causes OSNR degradation. Therefore, it is desirable to filter out the ASE noise from different transponders when multiplexing multiple wavelengths at the transmitter side, especially in a system with non-wavelength selective combiners such as directional couplers and multicast switches. The use of transponder aggregators with filtering functions, such as the M x N wavelength selective switch (WSS), is preferable for this filtering. However, the downside of these devices is that it is difficult to provide economical multiband support. Therefore, we propose an economical transponder aggregator configuration by allowing a certain amount of ASE superposition and reducing the number of filtering functions. In this paper, we fabricated a prototype of the proposed transponder aggregator by combining silica-based planar lightwave circuit technology and C+L band WSS, both commercially available, and verified its feasibility through transmission experiments. The novel transponder aggregator is a practical solution for a multiband CDC-ROADM system with improved OSNR performance.Comment: 10 pages, 11 figures. Submitted to IEEE Journal of Lightwave Technology for possible publicatio

    Cationized gelatin-HVJ envelope with sodium borocaptate improved the BNCT efficacy for liver tumors in vivo

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    <p>Abstract</p> <p>Background</p> <p>Boron neutron capture therapy (BNCT) is a cell-selective radiation therapy that uses the alpha particles and lithium nuclei produced by the boron neutron capture reaction. BNCT is a relatively safe tool for treating multiple or diffuse malignant tumors with little injury to normal tissue. The success or failure of BNCT depends upon the <sup>10</sup>B compound accumulation within tumor cells and the proximity of the tumor cells to the body surface. To extend the therapeutic use of BNCT from surface tumors to visceral tumors will require <sup>10</sup>B compounds that accumulate strongly in tumor cells without significant accumulation in normal cells, and an appropriate delivery method for deeper tissues.</p> <p>Hemagglutinating Virus of Japan Envelope (HVJ-E) is used as a vehicle for gene delivery because of its high ability to fuse with cells. However, its strong hemagglutination activity makes HVJ-E unsuitable for systemic administration.</p> <p>In this study, we developed a novel vector for <sup>10</sup>B (sodium borocaptate: BSH) delivery using HVJ-E and cationized gelatin for treating multiple liver tumors with BNCT without severe adverse events.</p> <p>Methods</p> <p>We developed cationized gelatin conjugate HVJ-E combined with BSH (CG-HVJ-E-BSH), and evaluated its characteristics (toxicity, affinity for tumor cells, accumulation and retention in tumor cells, boron-carrying capacity to multiple liver tumors <it>in vivo</it>, and bio-distribution) and effectiveness in BNCT therapy in a murine model of multiple liver tumors.</p> <p>Results</p> <p>CG-HVJ-E reduced hemagglutination activity by half and was significantly less toxic in mice than HVJ-E. Higher <sup>10</sup>B concentrations in murine osteosarcoma cells (LM8G5) were achieved with CG-HVJ-E-BSH than with BSH. When administered into mice bearing multiple LM8G5 liver tumors, the tumor/normal liver ratios of CG-HVJ-E-BSH were significantly higher than those of BSH for the first 48 hours (<it>p < 0.05</it>). In suppressing the spread of tumor cells in mice, BNCT treatment was as effective with CG-HVJ-E-BSH as with BSH containing a 35-fold higher <sup>10</sup>B dose. Furthermore, CG-HVJ-E-BSH significantly increased the survival time of tumor-bearing mice compared to BSH at a comparable dosage of <sup>10</sup>B.</p> <p>Conclusion</p> <p>CG-HVJ-E-BSH is a promising strategy for the BNCT treatment of visceral tumors without severe adverse events to surrounding normal tissues.</p

    Development of a novel artificial intelligence algorithm to detect pulmonary nodules on chest radiography

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    Background: In this study, we aimed to develop a novel artificial intelligence (AI) algorithm to support pulmonary nodule detection, which will enable physicians to efficiently interpret chest radiographs for lung cancer diagnosis. Methods: We analyzed chest X-ray images obtained from a health examination center in Fukushima and the National Institutes of Health (NIH) Chest X-ray 14 dataset. We categorized these data into two types: type A included both Fukushima and NIH datasets, and type B included only the Fukushima dataset. We also demonstrated pulmonary nodules in the form of a heatmap display on each chest radiograph and calculated the positive probability score as an index value. Results: Our novel AI algorithms had a receiver operating characteristic (ROC) area under the curve (AUC) of 0.74, a sensitivity of 0.75, and a specificity of 0.60 for the type A dataset. For the type B dataset, the respective values were 0.79, 0.72, and 0.74. The algorithms in both the type A and B datasets were superior to the accuracy of radiologists and similar to previous studies. Conclusions: The proprietary AI algorithms had a similar accuracy for interpreting chest radiographs when compared with previous studies and radiologists. Especially, we could train a high quality AI algorithm, even with our small type B data set. However, further studies are needed to improve and further validate the accuracy of our AI algorithm

    Prognostic Impact of Hypoxia-Inducible miRNA-210

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    Objective. The aim of this study was to investigate the prognostic value of MicroRNA-210 (miR-210) expression in patients with non-small-cell lung cancer (NSCLC). Methods. We examined the miR-210 expression of samples of 80 patients, who underwent surgical resection at Fukushima Medical University from 2004 to 2007, by using quantitative RT-PCR. The relationship between miR-210 expression and clinicopathological factors as well as histological subtype was statistically analyzed. Results. miR-210 expression showed an inverse correlation with disease-free and overall survival in patients with NSCLC. Significant correlations were found between miR-210 expression and lymph node metastasis, late disease stages, and poor prognosis in patients with adenocarcinoma. Multivariate Cox analysis indicated that miR-210 expression was an independent prognostic factor for disease-free survival in patients with adenocarcinoma. Conclusions. We showed that miR-210 may be a prognostic biomarker for patients with NSCLC, especially for those with lung adenocarcinoma
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