Feasibility of cryopreserved tracheal xenotransplants with the use of short-course immunosuppression

AbstractObjective: We evaluated the feasibility of discordant xenotransplantation of the cryopreserved trachea with intermittent immunosuppression to help solve the shortage of donor tracheas. Methods: Two experiments were performed with heterotopic transplantation models in 14 guinea pigs and 85 rats. So that the minimal dose of FK506 for viable fresh xenografts could be determined, FK506 was given in escalating doses (0, 1.5, 2.5, and 3.5 mg/kg) for recipient animals after xenogeneic transplantation. With the goal of obtaining a long-term survival of the xenografts, the effect of cryopreservation on xenografts was assessed and thereafter different cycles of immunosuppression every third week were evaluated in fresh or cryopreserved xenografts in the second experiment. Results: An FK506 dosage of more than 2.5 mg/kg per day was much more effective than smaller dosages, as demonstrated by morphologic assessment. A higher dosage of FK506 potentially delayed the rejection of xenografts and can thus maintain tracheal xenograft viability for less than 4 weeks in rat recipients. In experiment 2, the cryopreserved xenografts showed less histologic viability than fresh xenografts but greater patency of the lumen. The patency of cryopreserved xenografts was favorably maintained for a longer period than that of fresh xenografts with either the same number or more cycles of immunosuppression. Conclusions: We conclude that the synergistic effect of cryopreservation and adequate intermittent immunosuppression may enable tracheal xenografts to remain viable over longer periods. (J Thorac Cardiovasc Surg 2001;121:241-8

Examination of AI Literacy Education Using Generative AI

In this study, we examined the effectiveness of AI literacy education utilizing generative AI among students in liberal arts programs. Through several years of investigation, we conducted student surveys to evaluate its impact. The results consistently demonstrated a growing interest and motivation among students towards learning about AI and programming. Particularly noteworthy was the significant surge in interest and motivation observed in 2023, coinciding with the adoption of generative AI. The incorporation of exercises involving generative AI enabled students to recognize the efficacy of AI technology and understand the significance of collaboration between AI systems and humans in creative endeavors. The AI literacy education employing generative AI proved successful in fostering enthusiasm for creative work and enhancing studentsʼ motivation to explore AI further. To further improve educational outcomes, it is essential to conduct detailed analysis of qualitative feedback and refine exercise design. Additionally, conducting comparative studies across different student demographics and implementing long-term follow-up surveys are recommended.特集　AI と教育AI and Education専攻: 環境情報学departmental bulletin pape

Seasonal and Regional Characteristics of Aerosol Pollution in East and Southeast Asia

The atmospheric aerosol distribution in Asia is complex because it is influenced by both natural phenomena and human activities. In this article, multifaceted approach using satellite observations and numerical model simulation shows seasonal and regional variations of the aerosol distribution over Asia. Asia covers a large area; however, this article is limited to East and Southeast Asia. The aerosol optical thickness (AOT) in the inland desert area is normally high in spring and dusty aerosols are widely spread with the wind. The AOT values are high in summer over East Asia. A high AOT caused by biomass burning plumes is observed in autumn over Southeast Asia and in spring over Siberia and heavy air pollution occurs in Beijing in winter, a very well-known phenomenon. These phenomena caused by heavy aerosol concentration were determined based on Aqua/MODIS data and aerosol characteristics retrievals and estimated the aerosol characteristics. Furthermore, the impact of aerosols on the climate assessed by numerical model simulations suggest that aerosols reduce solar radiation and therefore the Earth's surface temperature. In addition to these influences on the radiation budget, aerosols have a significant potential to change the circulation fields

Estimation of Biomass Burning Influence on Air Pollution around Beijing from an Aerosol Retrieval Model

We investigate heavy haze episodes (with dense concentrations of atmospheric aerosols) occurring around Beijing in June, when serious air pollution was detected by both satellite and ground measurements. Aerosol retrieval is achieved by radiative transfer simulation in an Earth atmosphere model. We solve the radiative transfer problem in the case of haze episodes by successive order of scattering. We conclude that air pollution around Beijing in June is mainly due to increased emissions of anthropogenic aerosols and that carbonaceous aerosols from agriculture biomass burning in Southeast Asia also contribute to pollution

Interpretation of atmospheric particles at an urban area

Simultaneous measurements of atmospheric aerosols and suspended particulate matter (SPM) have been undertaken at Kinki University campus in Higashi-Osaka in order to monitor the urban environment. The sun/sky photometry has been made as a NASA/AERONET station since 2002, and the SPM-613D (Kimoto Electric) has been taking measurements of the SPM concentrations such as TSP, PM_, PM_, and OBC at the same site since March 15, 2004. The relationship between aerosol properties obtained from radiometry with AERONET and the SPM measurements is examined. It is found that there is a linear correlation between SPM concentrations and aerosol properties, which indicates that aerosol characteristics can be estimated from SPM data, and vice versa. Furthermore chemical analysis of the SPM sampling strongly suggests the really complicated features of the atmospheric particles at Higashi-Osaka. In other words, it is shown that the air quality of the Higashi-Osaka site is poor due to not only anthropogenic particles by local emissions, such as diesel vehicles and chemical industries, but also due to dust particles coming from continental desert areas by large scale climatic conditions.本文データの一部は、CiNiiから複製したものである