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We live in a colorful world, and it is important for us to receive visual information from colors in situations such as when we read a map. However, such important color-based information cannot be accurately received by some people. These people generally have some type of color vision deficiency such as protanopia or deuteranopia. It is important to realize their difficulties in recognizing differences in colors and provide a solution to this problem. We have proposed a lightness modification method that is designed to convey color information to protanopes and deuteranopes. The proposed method modifies the lightness of an input image by considering color differences so that the modified output image presents visual information for protanopes and deuteranopes. The proposed method changes the lightness of an image without changing the hue. Compared with existing hue changing methods, the output image obtained by the proposed method has more natural colors. Compared with existing lightness modification methods, the output image obtained by the proposed method has more contrast. In this paper, improvement points and parameter setting about the proposed method is described in details. We conducted experiments to show features of the proposed method against existing methods. In addition, we also show the limitation of the proposed method in this paper.

There are color vision barrier-free conversion algorithms that are used to improve the contrast in images for dichromats. The algorithms focus on whether dichromats can distinguish a combination of colors and often use a simulation model of color appearance for dichromats. To adjust the algorithms for individual dichromats, it is necessary to investigate whether the simulation model used is suitable for them in the vicinity of the color discrimination threshold $${\Theta }$$; however, there have been few such studies. In this paper, we propose a method of judging the suitability of a simulation model for dichromatic color appearance in the vicinity of $${\Theta }$$ using psychophysical measurements. In our method, gradually changing colors in the RGB color space are presented (Presentation A) to a dichromat and $${\Theta }^\text {A}$$ is obtained. Moreover, colors that are simulated by a target model are also presented (Presentation B) to the dichromat and $${\Theta }^\text {B}$$ is obtained. The suitability of the simulation model for the dirchromat is quantitatively judged by comparing $${\Theta }^\text {A}$$ and $${\Theta }^\text {B}$$ using statistical methods. An application example of the proposed method is also described to concretely show the procedure of the method.

Color correction for color vision deficiency is to correct confusion colors in an input image to colors which can be distinguished. There is such a color correction method which simultaneously considers contrast improvement and suppressing the over correction. However, the method has a problem that the color difference for people with color vision deficiency in an output image is sometimes not consistent with the set target value. We propose a new method which solves the problem.

Hospitals are increasingly challenged by nosocomial infection (NI) outbreaks during the ongoing coronavirus disease 2019 (COVID-19) pandemic. Although standardized guidelines and manuals regarding infection prevention and control (IPC) measures are available worldwide, case-studies conducted at specified hospitals that are required to cope with real settings are limited. In this study, we analyzed three hospitals in Japan where large-scale NI outbreaks occurred for hints on how to prevent NI outbreaks. We reviewed openly available information from each hospital and analyzed it applying a three domain framework: operation management, identification of infection status, and infection control measures. We learned that despite having authorized infection control teams and using existing standardized IPC measures, SARS-CoV-2 may still enter hospitals. Early detection of suspected cases and confirmation by PCR test, carefully dealing with staff-to-staff transmission were the most essential factors to prevent NI outbreaks. It was also suggested that ordinary training on IPC for staff does not always provide enough practical knowledge and skills, in such cases external technical and operational supports are crucial. It is expected that our results will provide insights into preventing NI outbreaks of COVID-19, and contribute to mitigate the damage to health care delivery systems in various countries.

A novel color removal method for digital color images is proposed. In this method, differences of colors in an input color image are reflected effectively, and the perceived lightness coming from the input color image is preserved as much as possible in order to realize the natural color-to-gray conversion. The effectiveness and the validity of the proposed method are verified by some experiments.

Background: Chronic Obstructive Pulmonary Disease (COPD) is a systemic inflammatory disease, and often causes weight loss, which is considered as a poor prognostic factor. A Japanese herbal medicine, Hochu-ekki-to (TJ-41), was reported to prevent weight loss in a small study of COPD patients, while its biological mechanism is unknown. Objective: The objective of our study was to evaluate the role of TJ-41 using mouse lung emphysema model, and to investigate its biological mechanism in vivo and in vitro. Methods: We used lung epithelial specific Taz conditional knockout mice (Taz CKO mice) as emphysema model mice, and fed a diet containing 2% TJ-41 or a control diet for 12 weeks. During administration, body weights were measured. After seeding, Taz CKO mice and control mice were subjected to BALF analysis, and lung mRNA expressions of inflammatory cytokines were analysed by RT-PCR. Results: After treatment, Taz CKO mice showed higher body weights in TJ-41 group compared to control diet group. BALF analysis showed decreased number of inflammatory cells in TJ-41 group, and among inflammatory cytokines, IL-8 expression was also significantly decreased. Conclusion: Our results suggest the possibility that TJ-41 attenuates lung inflammation, and thereby prevents weight loss of COPD patients. Among inflammatory cytokines, IL-8 is downregulated by administration of TJ-41, which coincided with decreased number of inflammatory cells in BALF in TJ-41 group. Our study sheds light on the biological mechanism of TJ-41 in lung emphysema, and suggests its potential for anti-inflammatory therapy for COPD patients.