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41.
Ranasinghe PD Satoh H Oshiki M Oshima K Suda W Hattori M Mino T 《Water science and technology》2012,66(10):2155-2161
The diversity of bacterial groups in activated sludge from large- and small-scale wastewater treatment plants was explored by barcoded pyrosequencing of 16S rRNA gene. Activated sludge samples (three small and 17 large scale) were collected from 12 wastewater treatment plants to clarify precise taxonomy and relative abundances. DNA was extracted, and amplified by 4 base barcoded 27f/519r primer set. The 454 Titanium (Roche) pyrosequences were obtained and analyses performed by Quantitative Insight Into Microbial Ecology (QIIME) with around 100,000 reads. Sequence statistics were computed, while constructing a phylogenetic tree and heatmap. Computed results explained total microbial diversity at phylum and class level and resolution was further extended to Operational Taxonomic Unit (OTU) based taxonomic assignment for investigating community distribution based on individual sample. Composition of sequence reads were compared and microbial community structures for large- and small-scale treatment plants were identified as major phyla (Proteobacteria and Bacteroidetes) and classes (Betaproteobacteria and Bacteroidetes). Also, family level breakdowns were explained and differences in family Nitrospiraceae and phylum Actinobacteria found at their species level were also illustrated. Thus, the pyrosequencing method provides high resolution insight into microbial community structures in activated sludge that might have been unnoticed with conventional approaches. 相似文献
42.
A neural oscillator with a double-chain structure is one of the central pattern generator models used to simulate and understand rhythmic movements in living organisms. However, it is difficult to reproduce desired rhythmic signals by tuning an enormous number of parameters of neural oscillators. In this study, we propose an automatic tuning method consisting of two parts. The first involves tuning rules for both the time constants and the amplitude of the oscillatory outputs based on theoretical analyses of the relationship between parameters and outputs of the neural oscillators. The second involves an evolutionary tuning method with a two-step genetic algorithm (GA), consisting of a global GA and a local GA, for tuning parameters such as neural connection weights that have no exact tuning rule. Using numerical experiments, we confirmed that the proposed tuning method could successfully tune all parameters and generate sinusoidal waves. The tuning performance of the proposed method was less affected by factors such as the number of excitatory oscillators or the desired outputs. Furthermore, the proposed method was applied to the parameter-tuning problem of some types of artificial and biological wave reproduction and yielded optimal parameter values that generated complex rhythmic signals in Caenorhabditis elegans without trial and error. 相似文献
43.
Network environments give computer users the option of employing distributed information and services to complete a task. However, gathering information and using services distributed in networks requires knowing exactly what kinds of information and services are required for a task, where they are, and how they can be obtained or utilized. Tracking down the answers to these questions can be difficult, time consuming tasks for users. Mobile agent technology is expected to release them from having to do so. Instead, “intelligent” mobile agents will comprehend the user's requirements, search network nodes autonomously for appropriate information and services, and return with the answers. But several problems must be solved before we can expect agents to perform such actions effectively. We focus on the question of intelligence as a prerequisite for agent functions. What sort of intelligence is expected of agents? We have adopted a model based on the ability to make flexible plans. Specifically, we think mobile agents must be able to: understand user requirements; plan actions that will satisfy the requirements act according to the plan; modify the plan according to actual conditions when they differ from those initially expected; and execute the modified plan. We have implemented these functions in the Plangent system and validated their effectiveness in several example applications. We describe how we combined these planning functions with mobile agent facilities, and show how the agents behave intelligently in an example application of personal travel assistance 相似文献
44.
Reiji Hattori Shuhei Yamada Yoshitomo Masuda Norio Nihei 《Journal of the Society for Information Display》2004,12(1):75-80
Abstract— We have developed new powder materials that exhibit liquid behavior, which can lead to the realization of novel bistable and reflective displays having paper‐white appearance, high contrast, and quick response. Two types of display were demonstrated, one had 160 × 160 array of pixels and the other had 320 × 320 in a 3.1‐in.‐diagonal viewable image size corresponding to 66 and 132 dpi, respectively. These displays were driven by passive‐matrix addressing. The displays showed a reflectivity of more than 41%, a contrast more than 1:10, and a pixel response time of less than 0.2 msec. The seven‐segment display for use in clocks was also demonstrated. 相似文献
45.
Ya-Li Wang Zhi-Jun Liu Qiang Liu Jian-Nan Ma Masao Hattori Chao-Mei Ma 《Food Analytical Methods》2014,7(7):1526-1529
Two cyanogenic glycosides (linustatin and neolinustatin) and sucrose were isolated from defatted flaxseed, and their structures were determined by NMR spectral analysis and comparison with existing data. Using secoisolariciresinol diglucoside (SDG) and the cyanogenic glycosides as standards, we developed a method to quantify the three compounds simultaneously by ultrahigh-performance liquid chromatography (UHPLC)-MS in selected reaction monitoring (SRM) mode. Using this tool, flaxseed powder—processed by various methods—was analyzed with regard to the contents of the beneficial compound, SDG, and the toxic compounds, cyanogenic glycosides. The levels of SDG in samples treated with alkaline solution are much higher than in samples without treatment, and in general, the levels of linustatin and neolinustatin in flaxseed powder decreased progressively as heating time is prolonged after treatment with alkaline solutions. 相似文献
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49.
Jomjai Peerapattana Kuniko Otsuka Yusuke Hattori 《Drug development and industrial pharmacy》2015,41(3):515-521
The objective of this research was to quantify the α-mangostin content in mangosteen pericarp (MP) ointment as a colloidal dispersion using near-infrared (NIR) spectroscopy. Various concentrations of MP (IP and EP) ointments containing both internal and external pericarps were prepared and the NIR spectra of these ointments were measured. The NIR spectrum of each ointment was correlated with α-mangostin concentration by partial least square (PLS) regression. Validation of the models was performed and their predictive ability was also investigated. The equation and R2 value for the prediction of α-mangostin concentration in IP ointment were y?=?0.9843x?+?0.4441 and 0.9730 and those in EP ointment were y?=?0.9569x?+?0.1142 and 0.9136, respectively. The biases of the IP and EP ointment models were 0.23 and 0.00, respectively. The results showed that NIR could be a useful tool for the quality control of herbal medicine in hydrophilic ointment without any sample preparation. It could predict α-mangostin content in hydrophilic ointment at very low concentration with sufficient accuracy. 相似文献
50.
Ryuta Shigefuku Hideaki Takahashi Hiroyasu Nakano Tsunamasa Watanabe Kotaro Matsunaga Nobuyuki Matsumoto Masaki Kato Ryo Morita Yousuke Michikawa Tomohiro Tamura Tetsuya Hiraishi Nobuhiro Hattori Yohei Noguchi Kazunari Nakahara Hiroki Ikeda Toshiya Ishii Chiaki Okuse Shigeru Sase Fumio Itoh Michihiro Suzuki 《International journal of molecular sciences》2016,17(9)
The progression of chronic liver disease differs by etiology. The aim of this study was to elucidate the difference in disease progression between chronic hepatitis C (CHC) and nonalcoholic fatty liver disease (NAFLD) by means of fibrosis markers, liver function, and hepatic tissue blood flow (TBF). Xenon computed tomography (Xe-CT) was performed in 139 patients with NAFLD and 152 patients with CHC (including liver cirrhosis (LC)). The cutoff values for fibrosis markers were compared between NAFLD and CHC, and correlations between hepatic TBF and liver function tests were examined at each fibrosis stage. The cutoff values for detection of the advanced fibrosis stage were lower in NAFLD than in CHC. Although portal venous TBF (PVTBF) correlated with liver function tests, PVTBF in initial LC caused by nonalcoholic steatohepatitis (NASH-LC) was significantly lower than that in hepatitis C virus (C-LC) (p = 0.014). Conversely, the liver function tests in NASH-LC were higher than those in C-LC (p < 0.05). It is important to recognize the difference between NAFLD and CHC. We concluded that changes in hepatic blood flow occurred during the earliest stage of hepatic fibrosis in patients with NAFLD; therefore, patients with NAFLD need to be followed carefully. 相似文献