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Background: Telemetry methods that allow low-cost, offshore tracking are required for the effective conservation and sustainable use of migratory fish in large lakes with vast and deep offshore areas. Surface drifting buoys, or drifters, are promising platforms for acoustic receiver attachment that have few operational constraints. However, the low recovery rate of drifters in the open ocean presents a challenge. In contrast, closed waters, such as lakes, are more suitable for operating drifters since drifting objects eventually strand on the shore. In this study, we examined the effectiveness of a single GPS-tracked drifter for telemetry surveys of the common carp Cyprinus carpio, which migrates throughout the large offshore area of a large lake, Lake Biwa, in Japan. Its performance was assessed regarding the success rate of drifter recovery, detection frequency of tagged individuals, search area of the drifter, and accuracy of detection locations. Results: We successfully recovered the drifter during all eight deployments. In 6 deployments, tagged individuals were detected 777 times. The drifter successfully detected 48% (10 of 21) of the tagged individuals, exhibiting higher performance (10–33%) than fixed receivers used in other telemetry studies conducted on highly migratory fish species in the lake. The drifter scanned an area of 5.5–8.0 km2 per day. Based on the data obtained from the field trials, the horizontal location accuracy of detected individuals was estimated to be approximately 400 m in shallow coastal areas and 600 m in deep offshore areas. Furthermore, the horizontal distance of tagged individuals traveled was estimated to be between 2 and 9 km within a day. Conclusion: Our newly developed method deploys and retrieves a single GPS drifter that allows low-cost, wide-ranging telemetry surveys in offshore areas of large lakes. The lack of boat noise, moderate moving speed, and continuity of observation range of the drifter seemingly enabled the efficient detection of tagged individuals. Thus, the drifter method offers a promising novel approach for acoustic telemetry in offshore waters that can operate in combination with large receiver arrays and other mobile platforms. [ABSTRACT FROM AUTHOR]

Purpose: Therapeutic drug monitoring guided by the area under the concentration-time curve (AUC-guided TDM) is recommended for vancomycin. However, validated efficient software remains elusive to popularize AUC-guided TDM in Japan. The aim of this study was to validate a newly developed web application, PAT, for AUC estimation. Methods: PAT was developed on the R ver. 3.6.2 platform for use with mobile phones and personal computers. AUC estimated by PAT (AUCPAT) was evaluated against the reference AUC (AUCREF) calculated with the log-linear trapezoidal rule using eight measured concentrations, or against AUC (AUCBM-P) calculated using an evaluated available software with clinical data. Results: Investigating the best sampling points with limited sampling, PAT produced the least bias using two concentrations at 1 h and 11 h after the end of infusion (slope 1.18, intercept −15.57, median AUCPAT/AUCREF 0.93 [range 0.81–1.24]), where only one estimation (6%) was out of the predetermined acceptable range of 0.8–1.2. Employment of only a trough concentration was more biased (AUCPAT/AUCREF range 0.73–1.30 for 11 h, AUCPAT/AUCREF range 0.62–1.40 for 23 h). In comparison with the evaluated software, AUCPAT was not biased against the AUCBM-P (slope 1.04, intercept −15.80, median AUCPAT/AUCBM-P 1.00 [range 0.86–1.10]). Conclusions: The new application using two concentrations was appropriately validated and might be efficient in popularizing the AUC-guided TDM of vancomycin. [ABSTRACT FROM AUTHOR]

The mobile ecosystem has recently experienced a transition in platform leadership from network operators to mobile operating system providers. In each system the platform provider exerts effort in order to attract other firms for generativity and profitability. In this paper, we identify and analyze the working mechanism of one business practice that significantly influences the ecosystem's generativity and platform provider's profitability via value appropriation. Revenue sharing has become a common practice in the mobile ecosystem following NTT DoCoMo's radical revenue-sharing model contributing toward mobile service success in Japan. Studies further argue that offering a wide portfolio of services through an attractive or innovative revenue-sharing model is one of key success factors in the mobile ecosystem. However, app developers have continuously claimed that they do not receive their fair share and the press reports a substantial number of disputes concerning revenue sharing between the platform provider and app developers. We propose a new bargaining model, the modified apex game, that investigates how value is likely to be appropriated between the platform provider and app developers within a given mobile platform mediated network. We support our theoretical predictions using data collected from the early mobile ecosystem by a network operator as well as the iOS and Android mediated networks. [ABSTRACT FROM AUTHOR]

Two clusters of the coronavirus disease 2019 (COVID-19) were confirmed in Hokkaido, Japan, in February 2020. To identify these clusters, this study employed web search query logs of multiple devices and user location information from location-aware mobile devices. We anonymously identified users who used a web search engine (i.e., Yahoo! JAPAN) to search for COVID-19 or its symptoms. We regarded them as web searchers who were suspicious of their own COVID-19 infection (WSSCI). We extracted the location of WSSCI via a mobile operating system application and compared the spatio-temporal distribution of WSSCI with the actual location of the two known clusters. In the early stage of cluster development, we confirmed several WSSCI. Our approach was accurate in this stage and became biased after a public announcement of the cluster development. When other cluster-related resources, such as detailed population statistics, are not available, the proposed metric can capture hints of emerging clusters. [ABSTRACT FROM AUTHOR]

Communication on the operation of a dam is crucial in evacuating residents before downstream flooding occurs. This paper examines the effect of communication regarding dam operation on evacuation, studying the case of the 2018 flooding of the Hijikawa River in Japan. After confirming the communication process and the messages of warning, we conducted a questionnaire survey of affected residents. The findings of the survey are as follows. (1) The discharge warnings issued by dam operators had no effect, because few people heard the warnings and even those who heard them were not inclined to evacuate. (2) Accepting the notifications from dam operators, local governments issued evacuation instructions. These instructions promoted evacuation. The most effective trigger of evacuation was route alerting by the volunteer fire corps. Information from dam operators induced the issuing of evacuation instructions, which activated the route alerting, and the information therefore indirectly promoted evacuation. (3) The Public Warning System operating on mobile phones had a certain effect in disseminating evacuation instructions where the system was used. (4) The messages issued here had insufficient specificity and clarity. A flood simulation considering the discharge flow of a dam needs to be conducted in addressing this issue. [ABSTRACT FROM AUTHOR]