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SBRT-VMAT planning is created manually, resulting in inconsistent plan quality and a time-consuming process. To improve efficiency and quality of planning, we evaluated the feasibility of AI-based automatic SBRT-VMAT planning for lung cancer. We developed the AI-based dose distribution prediction model (installed in RatoGuide prototype, AiRato. Inc) which was trained using manually optimized plans for 120 cases of stage I lung cancer (peripheral cases (55 Gy / 4 Fr) and central cases (50 Gy / 8 Fr), 54 cases each, both with PTV D95% prescription). Test data consisted of 6 treatment plans each of central and peripheral lung cancer. These plans were manually optimized and used for treatment, previously. The automatic plan was created following procedures: (i) predicting dose distribution based on target and OAR contours and CT images using RatoGuide, (ii) converting the predicted dose distribution into contours and importing them into the treatment planning system, and (iii) generating mimicked dose distributions using predefined optimization parameters and constraints. We measured the time to create plans and compared the DVH metrics between automatic and manual plans. Two expert radiation oncologists evaluated automatic and manual plans based on both visual inspection and DVH metrics in following aspects: (a) clinically acceptable or not and (b) preference for automatic or manual plan in clinical practice. DVH metrics and creation time for the 2 plans are shown in Table 1. No significant differences were observed in all DVH metrics between automatic and manual plans for peripheral cases, whereas significant differences were observed in some metrics of lungs for central cases. Radiation oncologists reviewed all automatic plans as clinically acceptable. The percentages of cases which 2 radiation oncologists preferred automatic plans to manual plans were 66.7% and 33.3%, respectively, for peripheral cases, and 91.7% and 50.0%, respectively, for central cases. Our newly developed method of automatic SBRT-VMAT treatment planning of lung cancer was fast and comparable to manually optimized plans in dose distribution. It can be feasible for clinical use, but we will focus on improving the accuracy of the prediction model and its workflow. [ABSTRACT FROM AUTHOR]

To evaluate properties of an initial growth layer for CoCrPt-Si[O.sub.2] perpendicular recording media, an initial growth layer has been investigated by micromagnetic simulation with initial layer model. It was found that with the initial growth layer, the in-plane magnetization [M.sub.in] shows a small jump at 0-field, leading to an additional peak around 0-field in 4 [pi] d[M.sub.in]/dH curve. The (additional) peak height increases with the increase in inter- lower subgrain exchange areal energy densities [w.sub.i] and thickness of the initial layer and also decreases in the anisotropy energy for the initial layer. Considering the change of the average anisotropy energy as a function of the thickness of recording layer, [w.sub.i] for a CoCrPt-Si[O.sub.2] perpendicular recording medium with Ru/Ru-Si[O.sub.2] intermediate layer is in the range from 0.5 to 0.6 erg/[cm.sup.2] and roughly 30% smaller than those with a Ru intermediate layer. Index Terms--CoCrPt-Si[O.sub.2] perpendicular recording media, differentiation of the in-plane magnetization, initial layer model, micromagnetic simulation, Ru/Ru-Si[O.sub.2] intermediate layer.

A Ru-SiO2 intermediate layer is introduced between Ru and recording layers to reduce the intermediate layer thickness of CoCrPt-SiO2 perpendicular recording media. A structural analysis revealed that the Ru-SiO2 intermediate layer enhanced the oxide segregation in the initial growth region of the recording layer.

CoB/Pd multilaycr films with a PtB/Pd/MgO intermediate layer were deposited on a soft-magnetic underlayer or on seeded substrates. A TEM analysis revealed that the multilayer films have a well-separated columnar structure just above an MgO layer. This structure may be initiated by the difference in the wetting nature of nonmetallic MgO and metallic Pd, and may be enhanced by the PtB layer. These boundaries were found to act in reducing the exchange coupling, resulting in an improvement in recording performance. Index Terms--CoB/Pd multilayer film, perpendicular magnetic recording, PtB/Pd/MgO intermediate layer.

The thermal stability and recording characteristics of a hybrid medium consisting of a granular CoCr-based alloy layer and an exchange-coupled Tb(Fe)Co layer are examined. High thermal stability is observed due to the increase in squareness and the decline in the nucleation field with the addition of a thin Tb(Fe)Co layer to a CoCrPt(B) medium.

A Ru–SiO2 intermediate layer was introduced between the Ru and recording layers to reduce the intermediate layer thickness of CoCrPt–SiO2 perpendicular recording media. A structural analysis revealed that the Ru–SiO2 intermediate layer enhanced the oxide segregation in the initial growth region of the recording layer. A micromagnetic simulation and magnetic property measurements indicated that the Ru–SiO2 intermediate layer reduced the intergranular exchange coupling in the initial growth region of the recording layer without magnetic anisotropy degradation. We reduced the intermediate layer thickness down to 9.1 nm by using the Ru–SiO2 intermediate layer while maintaining the signal-to-noise ratio. [ABSTRACT FROM AUTHOR]

Streptococcus mutans, a major pathogen of dental caries and infective endocarditis, is classified into serotypes c, e, f, and k, with serotype k strains recently reported to be frequently detected in persons with infective endocarditis. Thus, we hypothesized that common properties associated with infective endocarditis are present in those strains. Fifty-six oral S. mutans strains, including 11 serotype k strains, were analyzed. Western blotting analysis revealed expression of the 3 types of glucosyltransferases in all strains, while expression of the approximately 190-kDa cell-surface protein (PA) was absent in 12 strains, among which the prevalence of serotype k (7/12) was significantly high. Furthermore, cellular hydrophobicity and phagocytosis susceptibility were lower in the group of serotype k strains. These results indicate that the absence of PA expression, low cellular hydrophobicity, and phagocytosis susceptibility are common bacterial properties associated with serotype k strains, which may be associated with virulence for infective endocarditis. [ABSTRACT FROM AUTHOR]

Hyperthermia is a useful adjunct in cancer therapy as it can increase the effectiveness and decrease the toxicity of currently available cancer treatments such as chemotherapy and radiation. In the present study, we investigated whether 41°C hyperthermia (mild HT) for 20 min can enhance macrosphelide (MS5)-induced apoptosis in human lymphoma U937 cells. Our results revealed that, compared with MS5 (5 µM) and mild HT alone, the combined treatment exhibited significant enhancement in apoptosis at 6 h, which was evaluated by observing morphological changes and DNA fragmentation. Marked increase in the reactive oxygen species (ROS) generation was observed immediately after the combined treatment. Significant increase in Fas externalization, caspase-8 and caspase-3 activation, and loss of mitochondrial membrane potential (MMP) was found after the combined treatment compared with MS5 and mild HT alone. Moreover, this combination can also alter the expression of apoptosis-related proteins as evident by the cleavage of Bid and down-regulation of Bcl-2 while no change in the expression of Bax was observed. Furthermore, an immediate rise in the intracellular calcium ion ([Ca2+]i) concentration was observed after the combined treatment, which continuously increased in a time-dependent manner. In addition, mild HT treatment alone also increases [Ca2+]i concentration without inducing apoptosis. Our data indicate that early increase in ROS generation is mainly responsible for the enhancement of apoptosis after the combined treatment. [ABSTRACT FROM AUTHOR]

Influence of EPS on fouling of intermittent aeration MBR reactor (denitrification MBR) was investigated changing intermittent aeration cycle (10 minute-cycle and 120 minute-cycle) in laboratory-scale reactors using synthetic wastewater. EPS were extracted from bacterial cells using cation resin method and molecular weight fractioning of EPS was conducted using gel chromatography. In both of the reactors, nitrogen removal rate was almost 100% after 50th day although DO concentration was not very high during the aerated phase because of accumulation of nitrifying bacteria in the reactors. In the 120 minutes-cycle reactor, trans-membrane pressure increased more rapidly than in the 10 minutes-cycle reactor. The reason might be that EPS of more than 1000 kDa, which are the main fouling substances, are produced more rapidly in the 120 minute-cycle condition. It was also found that three peaks at around 100 kDa, 500 kDa and 2000 kDa are prominent in EPS in intermittent-aeration MBR irrespective of cycle and higher molecular weight EPS are decomposed to smaller molecular weight EPS on membrane surface. [ABSTRACT FROM AUTHOR]

Insulin-like growth factor-1 (IGF-1) can promote enterocyte proliferation which may be beneficial to postoperative conditions after massive small bowel resection (SBR) including the ileocecal valve (ICV). Wistar rats were subjected to SBR including or preserving ICV and continuously received IGF-1 or saline alone. Nutritional status, enterocyte proliferation, liver damage and hepatic IGF-1 mRNA levels were analyzed. Body weights, serum levels of total protein and transferrin, and enterocyte proliferation were significantly lower after SBR including ICV than preserving it. IGF-1 mRNA levels in the liver were decreased after SBR, especially after SBR including ICV. However, IGF-1 therapy significantly attenuated those decreased levels after SBR including ICV. Furthermore, IGF-1 significantly decreased serum liver transaminase levels which were increased after SBR including ICV. Continuous administration of IGF-1 may be available as a supplemented therapy for short bowel syndrome without ICV.Copyright © 2001 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Basal cell epithelioma (BCE) is one of the common malignant tumors of the skin, and it frequently arises in the exposed areas of elderly persons. Biologically BCE is locally destructive, but only rarely metastasizes. Pinkus and Mehregan attribute this biological characteristic to the interdependency between epithelial parenchyma and mesodermal stroma; i.e., BCE is one of fibro-epithelial tumors (1). Though several electron-microscopic studies on BCE have been done previously (2-8), little attention has been paid to the stroma. In this study we focused our attention on the stroma of this tumor. We frequently observed myofibroblasts in the stroma, some of which contained melanosomes. The latter finding seems to suggest that these cells have a phagocytic function. To our knowledge, no mention has hitherto been made of such function for myofibroblasts. [ABSTRACT FROM AUTHOR]