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Efforts to simplify standard polysomnography (PSG) in laboratories, especially for obstructive sleep apnea (OSA), and assess its agreement with portable electroencephalogram (EEG) devices are limited. We aimed to evaluate the agreement between a portable EEG device and type I PSG in patients with OSA and examine the EEG-based arousal index's ability to estimate apnea severity. We enrolled 77 Japanese patients with OSA who underwent simultaneous type I PSG and portable EEG monitoring. Combining pulse rate, oxygen saturation (SpO2), and EEG improved sleep staging accuracy. Bland–Altman plots, paired t-tests, and receiver operating characteristics curves were used to assess agreement and screening accuracy. Significant small biases were observed for total sleep time, sleep latency, awakening after falling asleep, sleep efficiency, N1, N2, and N3 rates, arousal index, and apnea indexes. All variables showed > 95% agreement in the Bland–Altman analysis, with interclass correlation coefficients of 0.761–0.982, indicating high inter-instrument validity. The EEG-based arousal index demonstrated sufficient power for screening AHI ≥ 15 and ≥ 30 and yielded promising results in predicting apnea severity. Portable EEG device showed strong agreement with type I PSG in patients with OSA. These suggest that patients with OSA may assess their condition at home. [ABSTRACT FROM AUTHOR]

There is an abundance of woody biomass in Japan. However, its economic feasibility is limited. There have been several discussions on whether generation of heat or electrical power is more suitable for woody biomass. In this study, we clarified the feasibility of generating heat and electricity from the viewpoint of biomass unit price and biomass productivity based on actual operation data for the first time. It was determined that heat production is feasible for a small-scale biomass energy use of 2,660 t/year or more. Electrical power generation is feasible only for a large-scale biomass energy use of 13,100 t/year or more, but it allows use of woody biomass with a higher unit price. [ABSTRACT FROM AUTHOR]

Stereocaulon sorediiferum is expected to be a Cu-hyperaccumulator lichen and has fluorescent substances. To clarify the relationship between the fluorescence (FL) of the lichen and its Cu concentration, we collected S. sorediiferum samples at Cu-contaminated and uncontaminated sites in Japan, determined the concentration of Cu, K, Mg, Al, Ca, Mn, Fe, Zn, chlorophyll a,b, and total carotenoids in them, analyzed lichen secondary metabolites and fluorescent substances extracted from them, and measured the FL of them and their extracts. We found that the FL intensity of S. sorediiferum samples is significantly negatively correlated with their Cu concentration. The application of its FL for Cu monitoring may allow a new nondestructive quantitative method for assessing Cu contamination. The spectroscopic and chromatographic analysis shows that the fluorescent substances negatively correlated with Cu concentration are not major lichen secondary metabolites (lobaric acid and atranorin) and remain after immersion in acetone. The correlation analysis and the comparison with the causal relationship between Cu concentration and the chlorophyll a/b ratio suggest that the reason for the decrease in FL intensity with increasing Cu concentration is a structural change of the fluorescent substances by accumulated Cu. These findings lead to a better understanding of the relationship between the FL of S. sorediiferum and its Cu concentration and provide new insights into fluorescent lichen substances. [ABSTRACT FROM AUTHOR]

Lichen secondary metabolites are known to be associated with heavy metal uptake and tolerance in lichens. Understanding the relationship between their secondary metabolites and heavy metals in them is important for clarifying the mechanisms of their heavy metal accumulation and tolerance. To determine the relationships between the concentrations of secondary metabolites and Cu in the Cu-hyperaccumulator lichen Stereocaulon japonicum and to clarify its response to Cu, we collected Cu-contaminated and uncontaminated samples of the lichen and determined relative concentrations of secondary metabolites and concentrations of Cu, K, glucose, and sugar alcohols in them. We found significant negative correlations between the relative concentrations of secondary metabolites—atranorin and stictic acid—and the concentration of Cu. These negative correlations can be interpreted in one of two ways: (a) S. japonicum itself reduced the relative concentrations of secondary metabolites in response to the increase of Cu concentration or (b) its carbon and energy metabolism was damaged by Cu stress, resulting in the reduction of the relative concentrations of secondary metabolites. The analysis of K, glucose, and sugar alcohols showed no effect of Cu on these concentrations, which means that the carbon and energy metabolism was not damaged by Cu stress. Therefore, the negative correlations can be interpreted that S. japonicum itself reduced the relative concentrations of secondary metabolites with the increase of Cu concentration. These findings provide a deeper understanding of the response of secondary metabolites to Cu in the lichen. [ABSTRACT FROM AUTHOR]

Based on quantification and qualification of bacterial 16S rDNA, we verified the bacterial ecological characteristics of surface sediments of Lakes Shinji and Nakaumi, which are representative of coastal lagoons in Japan. Quantification and qualification of the 16S rDNA sequences was carried out using real time polymerase chain reaction and polymerase chain reaction denaturing gradient gel electrophoresis and non-metric multidimensional scaling, respectively. The results revealed that the copy number per gram of sediment ranged from 8.33 × 10 (Lake Nakaumi) to 1.69 × 10 (Honjo area), suggesting that bacterial carbon contributed only 0.05-9.64 % of the total carbon content in the samples. Compared with other aquatic environments, these results indicate that sedimentary bacteria are not likely to be important transporters of nutrients to higher trophic levels, or to act as carbon sinks in the lagoons. The bacterial compositions of Lake Shinji and Lake Nakaumi and the Honjo area were primarily influenced by sediment grain sizes and salinity, respectively. Statistical comparisons of the environmental properties suggested that the areas that were oxygen-abundant (Lake Shinji) and at a higher temperature (Honjo area) presented efficient organic matter degradation. The 16S rDNA copy number per gram of carbon and nitrogen showed the same tendency. Consequently, the primary roles of bacteria were degradation and preservation of organic materials, and this was affected by oxygen and temperature. These roles were supported by the bacterial diversity rather than the differences in the community compositions of the sedimentary bacteria in these coastal lagoons. [ABSTRACT FROM AUTHOR]

First-principles fully relaxed tensile and shear test simulations were performed on $\Sigma {\rm{3(111)/[1{ \overline 1} 0]}}$ tilt Fe grain-boundaries (GBs) with and without hydrogen (H) segregation, to investigate the mechanisms of GB embrittlement enhanced by H segregation. Premature fracture was found in the H-segregated GB, compared with the clean GB, in the tensile test simulations. The Fe–H bond showed covalent-like and ion-like characteristics. The covalent-like characteristics reinforced the Fe–Fe bonds, but the ion-like characteristics weakened the Fe–Fe bonds as a result of charge transfer. The effect of the latter increased with increasing strain, and prevailed over the former, resulting in GB embrittlement. In the shear test simulations, variation in the GB energy for the H-segregated GB was almost the same as that for the clean GB. This is because bond-breaking and rebonding occur concurrently in GB shearing and the variations in charge transfer during shear straining are less than those during tensile straining. [ABSTRACT FROM PUBLISHER]

Trichloroethylene (TCE) is extensively used in commercial applications, despite its risk to human health via soil and groundwater contamination. The stability of TCE, which is a useful characteristic for commercial application, makes it difficult to remove it from the environment. Numerous studies have demonstrated that TCE can be effectively removed from the environment using bioremediation. Pseudomonas putida F1 is capable of degrading TCE into less hazardous byproducts via the toluene dioxygenase pathway (TOD). Unfortunately, these bioremediation systems are not self-sustaining, as the degradation capacity declines over time. Fortunately, the replacement of metabolic co-factors is sufficient in many cases to maintain effective TCE degradation. Thus, monitoring systems must be developed to predict when TCE degradation rates are likely to decline. Herein, we show evidence that tod expression levels correlate with the ability of P. putida F1 to metabolize TCE in the presence of toluene. Furthermore, the presence of toluene improves the replication of P. putida F1, even when TCE is present at high concentration. These findings may be applied to real world applications to decide when the bioremediation system requires supplementation with aromatic substrates, in order to maintain maximum TCE removal capacity. [ABSTRACT FROM AUTHOR]

A rapid approach based on two-dimensional DNA gel electrophroesis (2-DGE) mapping with selective primer pairs was employed to analyze bacterial community structure in sediments from upstream, midstream and downstream of Sagami River in Japan. The 2-DGE maps indicated that Alpha- and Delta-proteobacteria were major bacterial populations in the upstream and midstream sediments. Further bacterial community structure analysis showed that richness proportion of Alpha- and Delta-proteobacterial groups reflected a trend toward decreasing from the upstream to downstream sediments. The biomass proportion of bacterial populations in the midstream sediment showed a significantly difference from that in the other sediments, suggesting that there may be an environmental pressure on the midstream bacterial community. Lorenz curves, together with Gini coefficients were successfully applied to the 2-DGE mapping data for resolving evenness of bacterial populations, and showed that the plotted curve from high-resolution 2-DGE mapping became less linear and more an exponential function than that of the 1-DGE methods such as chain length analysis and denaturing gradient gel electrophoresis, suggesting that the 2-DGE mapping may achieve a more detailed evaluation of bacterial community. In conclusion, the 2-DGE mapping combined with the selective primer pairs enables bacterial community structure analysis in river sediment and thus it can also monitor sediment pollution based on the change of bacterial community structure. [ABSTRACT FROM AUTHOR]

We present a minimal two-component model that can exhibit various types of spatial patterns including patchiness. The model, comprising nutrients and phytoplankton, includes the effect of nutrient uptake by phytoplankton as a Holling type II functional response, and also includes the effect of zooplankton grazing on phytoplankton as a Holling type II non-dynamical term. The mean-fi eld model without the diffusion and advection terms shows both bistability and limit-cycle oscillations as a few parameters such as the input rate of nutrients and the maximum feeding rate of zooplankton are changed. If the parameter values are chosen from the limit-cycle oscillation region, the corresponding reaction-advection-diffusion equations show spatial pattern formations by the combined effects of advection and diffusion by turbulent stirring and mixing, and biological interactions. As the nutrient input is increased, the system behaviour changes from the extinction of the entire phytoplankton to the formation of filamentous patterns, patchiness patterns and homogeneous distributions. These observations suggest that the spatial pattern of phytoplankton can function as an indicator to evaluate the eutrophication level in aquatic ecosystems. [ABSTRACT FROM AUTHOR]

A practical guideline for community-level ecological risk management is proposed, with particular emphasis on the mutual interdependencies of the scientific analysis, public consensus building, and an adaptive management. The procedure we recommend spans the screening of potential ecological risks, the involvement of related stakeholders, the conceptual development from the “undesired event” over assessment endpoints to measures of effect and stress factors, the risk assessment for the no-action case, the planning phase from the public decision to become active and the setting of goals over a specification of monitoring and control methods to an assessment of feasibility and a public approval of the management plan and finally the adaptive management from initiation over continued monitoring to revisions of the plan, if required. The procedure contains several checkpoints, alternative routes, and possibilities to correct previous decisions. [ABSTRACT FROM AUTHOR]

So far a necessary and sufficient condition for the global asymptotic stability of linear mixed monotone delayed differential equation with time varying delay has been presented. However, several basic tools utilized for that proof are not restricted to linear functions. Here it is proved that similar results are obtained for the global asymptotic properties of nonlinear delay differential equation with analogous properties. [ABSTRACT FROM AUTHOR]

The idea of stochastic resonance (SR) is extended to two-parameter dynamical systems based on the Oregonator model of the Belousov-Zhabotinsky (BZ) reaction. The first case presents the photosensitivity of the reaction, and light flux and a flow rate are the two control parameters. The second case presents the effect of temperature on the oscillatory behaviors, and temperature and a flow rate are the control parameters. Stochastic resonance is demonstrated in the first case in which a signal and noise are applied to the different inputs, respectively. The scenario and novel aspects of SR in two-parameter systems are discussed, and the possibility of the analogous SR in biological systems is also pointed out. [ABSTRACT FROM AUTHOR]

The previously obtained stabilizing control for the delayed linear systemsis developed to the systems which can provide only two state variablesincluding no delays, whereas whole state variables were needed so far. Thesetwo state variables are the ones specified in relation to the uncertainparameters. The obtained condition is equivalent to the previous one.However, to obtain the same size of attracting region controls with largergains are needed comparative to the previous result. [ABSTRACT FROM AUTHOR]