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Highlights • US-IMPT can potentially reduce the risk of genitourinary toxicities. • The urethral NTCP value in US-IMPT is significantly lower than in the clinical plan. • TCP for CTV did not differ significantly between the clinical and US-IMPT plans., Background and Purpose Urethra-sparing radiation therapy for localized prostate cancer can reduce the risk of radiation-induced genitourinary toxicity by intentionally underdosing the periurethral transitional zone. We aimed to compare the clinical impact of a urethra-sparing intensity-modulated proton therapy (US-IMPT) plan with that of conventional clinical plans without urethral dose reduction. Materials and Methods This study included 13 patients who had undergone proton beam therapy. The prescribed dose was 63 GyE in 21 fractions for 99% of the clinical target volume. To compare the clinical impact of the US-IMPT plan with that of the conventional clinical plan, tumor control probability (TCP) and normal tissue complication probability (NTCP) were calculated with a generalized equivalent uniform dose-based Lyman–Kutcher model using dose volume histograms. The endpoints of these model parameters for the rectum, bladder, and urethra were fistula, contraction, and urethral stricture, respectively. Results The mean NTCP value for the urethra in US-IMPT was significantly lower than that in the conventional clinical plan (0.6% vs. 1.2%, p

Highlights • Post urination MRI is useful for urethra-sparing radiotherapy treatment planning. • This prospective clinical trial included 11 prostate cancer patients. • Post urination MRI is the identification method of prostatic urinary tract in non-invasive manner., The urethra position may shift due to the presence/absence of the catheter. Our proposed post-urination-magnetic resonance imaging (PU-MRI) technique is possible to identify the urethra without catheter. We aimed to verify the inter-operator difference in contouring the urethra by PU-MRI. The mean values of the evaluation indices of dice similarity coefficient, mean slice-wise Hausdorff distance, and center coordinates were 0.93, 0.17 mm, and 0.36 mm for computed tomography, and 0.75, 0.44 mm, and 1.00 mm for PU-MRI. Therefore, PU-MRI might be useful for identifying the prostatic urinary tract without using a urethral catheter. Clinical trial registration: Hokkaido University Hospital for Clinical Research (018-0221).

Slip flow phenomena are of great concern in aerosol filtration because of their ability to develop low-pressure drops and high collection efficiency air filters by using nanofibers. However, it is a difficult task to verify the slip flow effect on the reduction in pressure drop because the inhomogeneity in fiber packing also results in a decrease in pressure drop. In the present work, we propose pressure drop measurements at low pressures to verify the slip flow effect by distinguishing the effects of filter inhomogeneity. We found that the experimental dimensionless drag at low-pressure conditions, which was obtained with correction by the inhomogeneity factor measured at atmospheric pressure, followed the theoretical prediction that includes the slip flow correction (Kirsch and Stechkina, 1978) for both conventional PTFE and newly developed fluororesin nanofiber filter media. Because the dimensionless drags of both nanofiber filters decreased inversely proportional to the Knudsen number, we concluded that these nanofiber filters have low-pressure drops because of slip flow effects.

Straight and bead-free nanofibers were synthesized via electrospinning by adding potassium iodide to a precursor containing polyacrylonitrile dissolved in dimethylformamide. Nano- and submicron-fibers with diameters of 36.5–300 nm were electrospun on the surface of a microfiber mat as the base filter to form a strong multilayer filter. The size of the fibers was controlled by adjusting the electrospinning atmosphere (i.e., temperature and humidity) and polyacrylonitrile and potassium iodide concentrations in the precursor solution. The pressure drop of the prepared multilayer filters was measured simultaneously in an aerosol filtration test using monodispersed aerosol particles of diameter 100 nm. Interestingly, the rate of pressure drop was reduced for filters composed of nanofibers with a diameter of less than 100 nm deposited on the base filter. In this case, the pressure drop was more gradual than was expected for a continuous flow pattern, mainly because of the slip flow effect. Because the thickness of the boundary layer for mass transfer is greater when nanofibers are thinner, the filtration efficiency of these filters was almost constant. Further reduction of the fiber diameter leads to the flow condition entering the free-molecular regime.

In this study, an e-learning system is developed to handle the e-learning environment based on the learning ecological model. In the learning ecological model, which represents the comprehensive e-learning environment, not only the contents of learning, but also the learning environment are managed and provided, based on the content, the goal, and the configuration of the learning. The major purpose of this study is to realize the function that can manage the diversified learning objects with various information granularities and representation formats, using the learning object metadata, so that each learner can utilize the learning object based on the learning scenario, which is matched to the individual learner. The learning scenario is constructed by sequencing the learning objects based on the learning necessity, the learning history information, and the curriculum information of the object of learning, according to the characteristics of the learning object. As the sequencing procedure, the sequencing of the learning objects is considered, by applying the optimization technique of the multi-objective optimization problem, so that multiple evaluation viewpoints are simultaneously satisfied. The genetic algorithm is used as the optimization procedure. The learning object metadata and the sequencing of the learning objects are discussed in detail in this paper. The evaluation of the developed e-learning system is also described. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 88(3): 54–71, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.20163

With the rapid development of information technology (IT) and the Internet growth, it is widely accepted that computer and information communication literacy has become extremely important, and will play a major part in everyone's lives in the future. In order to teach the next generations computer literacy, it is first necessary to train our teachers. In Japan a new teachers' education framework is being built, to enhance the teachers' teaching skills and information literacy, with special focus on Internet and Multimedia. Our research belongs to this new research direction. The purpose of this study is to propose and develop a distance educational model, as a school-based curriculum development and training-system. In this environment, a teacher can learn via an Internet-based self-training system about subject contents, modern teaching know-how, and students' learning activities evaluation methods, about the new subject called "Information". We call our system RAPSODY: Remote and AdaPtive educational System Offering a DYnamic communicative environment. In this paper, we describe the structure, functions and mechanism of our distance educational model and then discuss the educational meaning of this model within the new learning ecology, based on multi-modality and new learning situations and forms. Finally, we perform some tests and evaluation and show our current results.

The Industry and University cooperation program is a project of the Japanese Ministry of Education (Mombusho). The target objective of this program is the harmonization of university level educational research, society practice and practical business. The University of Electro-Communications has been appointed by Mombusho to fulfill some specific parts of this program. The authors report on their experience with the introduction of this program, its framework, settings, actual implementation and preliminary findings. The problems encountered are discussed, together with a number of solutions to assist good practice in the building of such an applied educational program. Career development, via acquiring of experience and knowledge in the field of information communication technology, is an important subject for the future information communication society. The program's starting courses involve this discipline. The lectures were focused on high information technology, large-scale information system planning and application, and network technology.

With the rapid development of information technology, it is widely accepted that computer and information communication literacy has become extremely important, and is the main new ability required from teachers everywhere. Therefore, for enhancing their teaching skills and information literacy about the Internet environment with multimedia, a new teachers' education framework is necessary. The purpose of the study, is to propose and develop a distance educational system, RAPSODY, which is a school-based curriculum development and training system. In this environment, a teacher can learn subject contents, teaching ways, and evaluation methods of the students' learning activities, related to the new subject called "Information", via an Internet based self-training system. The authors describe the structure, function and mechanism of the distance educational system based on the Distance Ecological Model, in order to realize the above-mentioned goal, and then describe the educational meaning of this model in consideration of the new learning ecology, which is based on multi-modality and new learning situations and forms.

PURPOSE/OBJECTIVE(S) In the treatment planning for urethra-sparing radiation therapy in localized prostate cancer, it is important to visualize the prostatic urinary tract to reduce the risk of urinary symptoms linked to the urethral dose. We developed a methodology for visualizing the prostatic urinary tract by post-urination magnetic resonance imaging (PU-MRI) without using a urethral catheter for urethra-sparing radiotherapy. Several super-resolution (SR) deep learning models were proposed for improving image quality. This study investigated whether these SR deep learning models improve the visibility of the prostatic urinary tract in PU-MRI. MATERIALS/METHODS We enrolled 30 patients who had previously undergone real-time-image-gated spot scanning proton therapy (RGPT) by inserting fiducial markers at our institution from October 2019 to October 2020. PU-MRI was performed using a non-contrast high-resolution two-dimensional T2-weighted turbo spin-echo (TSE) imaging sequence. Four different SR deep learning models were constructed: the EDSR (enhanced deep SR network), WDSR (widely activated SR network), SRGAN (SR generative adversarial network), and RDN (residual dense network). All models were trained using a diverse 2K resolution high-quality image dataset. We imported PU-MRIs as low-resolution images and exported four SR images that were enlarged using one of the models each. To assess the performance of the proposed SR image compared to PU-MRI, we used the complex wavelet structural similarity index measure (CW-SSIM) as the quantitative metric. A 1-to-5 scale was used to subjectively evaluate the visibility of the prostatic urinary tract by two radiation oncologists. RESULTS The mean (± standard deviation) of the CW-SSIM in the EDSR, WDSR, SRGAN, and RDN were 0.999 ± 0.001, 0.999 ± 0.002, 0.993 ± 0.002, and 0.997 ± 0.002, respectively. The mean prostatic urinary tract visibility scores for oncologist 1 and 2 were 3.70 ± 0.64 and 3.53 ± 0.99 for PU-MRI, 3.67 ± 0.60 and 2.70 ± 0.82 for EDSR, 3.70 ± 0.53 and 2.73 ± 0.81 for WDSR, 3.67 ± 0.65 and 2.73 ± 0.81 for SRGAN, and 4.37 ± 0.61 and 3.73 ± 0.93 for RDN, respectively. CONCLUSION This study investigated whether the combination of PU-MRI and SR deep learning models improves visibility of the prostatic urinary tract. The results suggest that SR images using RDN are highly similar to the original image and subjectively improve the visibility of the prostatic urinary tract.