Android IoT Lifelog System and Its Application to Motion Inference

In social science, health care, digital therapeutics, etc., smartphone data have played important roles to infer users’ daily lives. However, smartphone data collection systems could not be used effectively and widely because they did not exploit any Internet of Things (IoT) standards (e.g., oneM2M) and class labeling methods for machine learning (ML) services. Therefore, in this paper, we propose a novel Android IoT lifelog system complying with oneM2M standards to collect various lifelog data in smartphones and provide two manual and automated class labeling methods for inference of users’ daily lives. The proposed system consists of an Android IoT client application, an oneM2M-compliant IoT server, and an ML server whose high-level functional architecture was carefully designed to be open, accessible, and internationally recognized in accordance with the oneM2M standards. In particular, we explain implementation details of activity diagrams for the Android IoT client application, the primary component of the proposed system. Experimental results verified that this application could work with the oneM2M-compliant IoT server normally and provide corresponding class labels properly. As an application of the proposed system, we also propose motion inference based on three multi-class ML classifiers (i.e., k nearest neighbors, Naive Bayes, and support vector machine) which were created by using only motion and location data (i.e., acceleration force, gyroscope rate of rotation, and speed) and motion class labels (i.e., driving, cycling, running, walking, and stilling). When compared with confusion matrices of the ML classifiers, the k nearest neighbors classifier outperformed the other two overall. Furthermore, we evaluated its output quality by analyzing the receiver operating characteristic (ROC) curves with area under the curve (AUC) values. The AUC values of the ROC curves for all motion classes were more than 0.9, and the macro-average and micro-average ROC curves achieved very high AUC values of 0.96 and 0.99, respectively.     

Continuous operation of membrane bioreactor treating toluene vapors by Burkholderia vietnamiensis G4

A laboratory-scale biofilm membrane bioreactor inoculated with Burkholderia vietnamiensis G4 was examined to treat toluene vapors in a waste gas stream. The gas feed side and nutrient solution were separated by a composite membrane consisting of a porous polyacrylonitrile (PAN) support layer coated with a very thin (0.3 μm) dense polydimethylsiloxane (PDMS) top layer. After inoculation, a biofilm developed on the dense layer. The biofilm membrane bioreactor was operated continuously at different residence times (28–2 s) and loading rates (1.2–26.7 kg m⁻³ d⁻¹), with inlet toluene concentrations ranging from 0.21 to 4.1 g m⁻³. The overall performance of the membrane bioreactor was evaluated over a period of 165 days. Removal efficiencies ranging from 78% to 99% and elimination capacities from 4.2 to 14.4 kg m⁻³ d⁻¹ were observed after start-up period depending on the mode of operation. A maximum elimination capacity of 14.4 kg m⁻³ d⁻¹ was observed at a loading rate of 17.4 kg m⁻³ d⁻¹. Overall, the results illustrate that biofilm membrane reactors can potentially be more effective than conventional biofilters and biotrickling filters for the treatment of air pollutants such as toluene.     

Removal of dimethyl sulfide in a thermophilic membrane bioreactor

BACKGROUND: Several sources such as the paper and pulp industry and waste treatment plants emit waste gases containing volatile organic sulfur compounds at elevated temperature. Since cooling the hot gases increases the operational cost of biological reactors, application of thermophilic microorganisms could be a cost‐effective solution. The objectives of this study were to investigate the possibility of removal of dimethyl sulfide from waste gases under thermophilic conditions (52 °C) in a membrane bioreactor and to examine the long‐term stability of the reactor at elevated temperature. The effects of operating conditions such as gas residence time, nutrient supply, temperature decrease and short‐term shutdown on elimination capacity were investigated. RESULTS: A maximum elimination capacity of 54 g m^?3 h^?1 (0.108 g m^?2 h^?1) was obtained at a mass loading rate of 64 g m^?3 h^?1 (0.128 g m^?2 h^?1) with a removal efficiency of 84% at a gas residence time of 24 s. The long‐term operation of the thermophilic membrane bioreactor was followed for 9 months. Although the removal efficiency decreased to 50% after 3 months of continuous operation, it recovered (>96%) after the excess biomass was removed by applying high‐velocity liquid recirculation. CONCLUSION: This study demonstrated that the dimethyl sulfide removal is possible in a thermophilic membrane bioreactor with an elimination capacity of 54 g m^?3 h^?1 (0.108 g m^?2 h^?1) at a gas residence time of 24 s. Copyright © 2008 Society of Chemical Industry     

Boron-dependent regulation of translation through AUGUAA sequence in yeast

Under high boron (B) conditions, nodulin 26-like intrinsic protein 5;1 (NIP5;1) mRNA, a boric acid channel, is destabilized to avoid excess B entry into roots of Arabidopsis thaliana. In this regulation, the minimum upstream open reading frame (uORF), AUGUAA, in its 5′-untranslated region (5′-UTR) is essential, and high B enhances ribosome stalling at AUGUAA and leads to suppression of translation and mRNA degradation. This B-dependent AUGUAA-mediated regulation occurs also in animal transient expression and reticulocyte lysate translation systems. Thus, uncovering the ubiquitousness of B-dependent unique regulation is important to reveal the evolution of translational regulation. In the present study, we examined the regulation in Saccharomyces cerevisiae. Reporter assay showed that in yeast, carrying ATGTAA in 5′-UTR of NIP5;1 upstream of the reporter gene, the relative reporter activities were reduced significantly under high B conditions compared with control, whereas deletion of ATGTAA abolished such responses. This suggests that AUGUAA mediates B-dependent regulation of translation in Saccharomyces cerevisiae. Moreover, the deletion of ATGTAA resulted in up to 10-fold increase in general reporter activities indicating the suppression effect of AUGUAA on translation of the main ORF. Interestingly, mRNA level of the reporter gene was not affected by B in both yeast cells with and without AUGUAA. This finding reveals that in yeast, unlike the case in plants, mRNA degradation is not associated with AUGUAA regulation. Together, results suggest that B-dependent AUGUAA-mediated translational regulation is common among eukaryotes.     

Thermophilic biotrickling filtration of a mixture of isobutyraldehyde and 2‐pentanone

In this study, the possibility of the removal of isobutyraldehyde and 2‐pentanone was investigated in biotrickling filters (BTFs) at higher temperature (52–65 °C). First, the biodegradation of isobutyraldehyde and 2‐pentanone in activated sludge was proven by batch experiments at 52 and 62 °C. In batch experiments isobutyraldehyde was also degraded up to a temperature of 72 °C. Thereafter two bioreactors were operated in parallel, one at ambient temperature (BTF25), and one at 52 °C (BTF52). Maximum elimination capacities of 97 and 139 g m^?3 h^?1 were observed in BTF25 and BTF52, respectively, for isobutyraldehyde. Maximum elimination capacities of 53 and 63 g m^?3 h^?1 were obtained for 2‐pentanone in BTF25 and BTF52, respectively. A significant difference was observed in the operational stability of the two reactors. In the reactor at ambient temperature, operational problems such as foam formation, higher biomass accumulation and organic acid production were observed. In the thermophilic reactor these problems did not occur or were less severe. Copyright © 2007 Society of Chemical Industry