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Understanding the Gospel Based on the "Philosophy of Faithfulness" : Is the Vicarious Punishment Theory Consistent with the Philosopher Paul?
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Refugia within refugium of Geranium yesoense varieties : a follow-up study using chloroplast genome sequencing data of specimens from Mt. Asama, Japan
No full textRecent phylogeographical studies have revealed that refugia sometimes retain high levels of genetic heterogeneity due to multiple colonization events, a phenomenon defined as 'refugia within refugium'. In previous research, we reported a complex genetic structure within the Geranium yesoense complex, an alpine plant found in an interglacial refugium at high elevation in Central Japan, probably resulting from multiple colonization and hybridization events. However, we were unable to evaluate instances of introgression due to limited sample size. In the present study, we performed additional chloroplast genome sequencing, along with Sanger sequencing of selected chloroplast DNA regions, to elucidate the phylogenetic relationships among the refugial populations. The chloroplast genome sequence of a sample from Mt. Asama (an important refugium) was nested within the northern lineage (i.e. var. yesoense and var. pseudopratense), and haplotypes from Mt. Asama and Mt. Ibuki were also grouped with those of the northern lineage. Although our previous study suggested hybridization events between northern and southern lineages (i.e. var. nipponicum) at Mt. Asama, haplotypes from the southern lineage were not detected at range margins. This suggests that directional introgression occurred in these regions. Overall, our results further support that genetic heterogeneity within these refugia was amplified by recolonization and hybridization during past climate oscillations
Detection of negative ions in streamer discharge in air by transient cavity ringdown spectroscopy
No full textAtmospheric-pressure discharges generated in air are expected to be electronegative, but experiments that examine negative ion densities are limited to date. In this work, we measured the temporal variation of the negative ion density in a streamer discharge generated in air. We adopted cavity ringdown spectroscopy, where negative ions were detected via weak optical absorption caused by laser photodetachment. The temporal variation of the absolute negative ion density was deduced by the transient analysis of the ringdown curve. Negative ions were detected after the disappearance of the discharge voltage and current. The negative ion density started the increase at 0.4 mu s after the initiation of the discharge. The increase means the enhancement of the electron attachment frequency in the late phase of the secondary streamer with electron cooling. The survival of electrons until 0.4 mu s is understood by the steep decrease in the cross section of dissociative recombination with the electron energy. The maximum negative ion density was observed at 1 mu s, and it was around the noise level at 1.5 mu s. The rapid decay is consistent with the destruction of negative ions by mutual neutralization with positive ions
Impact of the Temperature, Homogenization Condition, and Oil Property on the Formation and Stability of Crude Oil Emulsion
No full textWater-in-oil (W/O) emulsions have garnered significant attention in the petroleum industry as a result of their adverse effects, such as reduced oil recovery, increased pressure drop, and equipment corrosion. This study investigated the influences of the temperature, homogenization conditions, and crude oil properties on emulsion formation and stability. We focused on nine crude oils with varying viscosities, observing the emulsion formation process and analyzing functional groups, percentage of resolved water, and emulsion particle sizes. Under all conditions, W/O emulsions for most oils underwent a transformation from multiple emulsions, including water-in-oil-in-water (W/O/W) and water-in-oil-in-water-in-oil-in-water (W/O/W/O/W) emulsions. As the temperature increased, the variation in the W/O emulsion amount at the end of the transformation differed on the basis of oil viscosity, while emulsion stability showed no significant differences. However, W/O emulsion stability increased after 24 h of aging at high temperatures. Additionally, four hypotheses regarding the final changes in the W/O emulsion amount with the temperature were consistent with the emulsion formation process. With regard to the effect of homogenization conditions, increasing shear intensity resulted in a larger amount of W/O emulsion with high stability. This was attributed to changes in the activity of different natural surfactants with increasing shear intensity. Furthermore, the final amount of W/O emulsion was primarily influenced by hydrogen-bonded O-H, followed by hydrogen-bonded N-H. The mechanisms underlying the influence of different factors on emulsion formation and stability are described
Tracing Sediment-Affected Water Masses From Coastal Areas to Offshore Oceans Using In Situ Sensing of Fluorescent Organic Matter
No full textThe lateral transport of nutrient-rich water masses from coastal areas to offshore areas is an important factor controlling the primary production of phytoplankton in offshore regions. If the coastal low-salinity waters have high nutrient levels, lateral transport can be traced via salinity observations. However, if high level of nutrients in the waters are not coupled with low salinity, for example, input from coastal sediments, water transport cannot be traced via salinity observations. In this study, visible fluorescent organic matter (FOMvis) was monitored by an in situ sensor as a tracer for sediment-affected water masses from coastal areas. The FOMvis distribution in the upper 500 m water layer in offshore Japan along the 143 degrees E transect was generally controlled by the distributions of subtropical water (i.e., Kuroshio water and Tsugaru warm current water) and subarctic water (i.e., Oyashio water). However, anomalously high levels of FOMvis were observed at depths of 20-60 m at an observational station, which could not be explained by physical mixing. This likely originated from the lateral transport of water masses from coastal areas. In and around Sendai Bay, where observations were carried out as an example of the Japanese coast, high levels of FOMvis were observed, accompanied by negative N*, an indicator of denitrification, and phosphate and silicic acid inputs from anoxic sediments. These observational results imply that FOMvis observation via in situ sensors can be useful for tracing the input of nutrient-rich sediment-affected water masses from coastal areas to offshore oceans. Phytoplankton activities in offshore oceans are often controlled by the supply of nutrients. Since the coastal oceans are generally characterized by high levels of nutrients, lateral transport of nutrients from the coastal ocean to the offshore ocean is likely an important nutrient source for phytoplankton, particularly in the boundary region. Rivers and sediments supply nutrients to coastal oceans. Nutrient transport accompanied by river water can be traced by salinity observations using conductivity sensors. However, the transport of sediment-derived nutrients is difficult to trace via sensor-based observations. The visible fluorescence of nonliving organic matter (traditionally defined as humic-like fluorescence) has been suggested to be useful for tracing river water as well as coastal sediment-affected water in marine environments. Here, we observed the simultaneous presence of sediment-derived nutrients and visible fluorescent organic matter, which was detected by a sensor in the subsurface layer in the coastal area, that is, in and around Sendai Bay, Japan. A relatively high level of fluorescent organic matter was also observed in the Kuroshio-Oyashio transition zone. These observational results indicate that fluorescent organic matter as detected by in situ sensors can be useful for tracing inputs of coastal sediment-derived nutrients to offshore oceans. A portion of the fluorescent organic matter in the Kuroshio-Oyashio transition zone could be laterally transported from coastal areas High levels of fluorescent organic matter in subsurface layers in coastal regions are linked with sediment-derived nutrients Sensor-based observation of fluorescent organic matter can be used to effectively trace the export of coastal sediment-derived nutrient
Unpacking the relationship between cultural diversity and workgroup creativity
No full textPurposeThis study aimed to illustrate the conditions under which cultural diversity enhances workgroup creativity. It does so by investigating the impact of ethnic diversity on workgroup creativity through the mediating mechanisms of cognitive diversity and information elaboration, while also exploring the role of inclusive leadership in this process.Design/methodology/approachMulti-source data was collected from a sample of 338 employees nested within 56 workgroups across three distinct organizations. Conditional process analysis was used to empirically test the proposed hypotheses.FindingsThe results show that ethnic diversity, a surface-level cultural attribute, contributed to diversity in deep-level cognitive resources, and that workgroups were able to capitalize on these variations in deep-level cognitive resources to enhance their creativity when they engaged in the elaboration of task-relevant information. Results also demonstrated that the effective management of workgroup processes through inclusive leadership helped materialize the performance-promoting effects of cultural diversity. Overall, the findings support the notion that cultural diversity is indeed beneficial to workgroups.Originality/valuePrior research has typically examined cultural diversity in workgroups from the perspective of either surface-level or deep-level cultural attributes, leading to conflicting findings. Our study takes a multifaceted approach to cultural diversity and its influence on workgroup creativity, offering a more nuanced understanding. Additionally, by integrating the concept of inclusive leadership, a relatively new conceptualization of leadership specifically relevant to diverse workgroups, we clarified strategies for fostering positive workgroup performance
ウェブ小説研究 : ネット社会における模倣的創造文化の可能性について [全文の要約]
No full textこの博士論文全文の閲覧方法については、以下のサイトをご参照ください。https://www.lib.hokudai.ac.jp/dissertations/copy-guides
進化的大規模最適化アルゴリズムに関する研究
No full textEvolutionary computation (EC), a sub-field of artificial intelligence (AI) and soft computing, constitutes a family of global and stochastic optimization techniques inspired by natural phenomena and organism behaviors. Thanks to its superior characteristics of robustness, scalability, gradients-free, and easy implementation, it has found wide application in academic research and real-world scenarios. However, as the scale of the optimization problem increases, an inevitable issue known as the curse of dimensionality arises. In this phenomenon, the search domain of the problem also expands exponentially and simultaneously. This phenomenon significantly deteriorates the performance of EC techniques and exacerbates the complexity and difficulty of problems. When the scale of the problem reaches a specific dimension (e.g., 1000-D), this type of problem is referred to as a large-scale optimization problem (LSOP). This dissertation proposes two directions to deal with LSOPs with EC techniques: (1). Introducing the cooperative coevolution (CC) framework and (2). Enhancing the performance of EC techniques. Motivated by divide-and-conquer, the CC framework decomposes the LSOP into multiple sub-components and optimizes them independently and alternatively, which can alleviate the negative influence of the curse of dimensionality.However, few studies focus on the robustness of decomposition methods such as realcoded linkage identification by nonlinearity check (LINC-R). These methods cannot detect separability between decision variables in noisy environments. To overcome this problem, we propose linkage measurement minimization (LMM). Although it is difficult for conventional LINC-R and differential grouping (DG) based methods to identify the interactions through the absolute strength of interaction with thresholds, we hypothesize the strength between originally separable and non-separable decision variables is distinct in noisy environments, and this relative strength can help algorithm identify the separability and form the sub-components automatically. Additionally, most studies focus on identifying additive separability between decision variables and improving decomposition accuracy while reducing computational complexity, and other kinds of separability are rarely investigated, such as multiplicative separability and composite separability. Therefore, we propose Efficient Dual Differential Grouping (EDDG), which incorporates the principle of identifying multiplicative interactions into the framework of Efficient Recursive Differential Grouping (ERDG). Our proposed EDDG is expected to detect both additive and multiplicative interactions simultaneously while consuming minimal computational resources. Another direction to achieve the objective of this dissertation is to enhance the performance of optimizers. Furthermore, the EC technique can mainly be divided into metaheuristic algorithm (MA) and hyper-heuristic algorithm (HHA). For MAs, we pay attention to the two MAs: bio-inspired vegetation evolution (VEGE) and physics-based RIME optimization. The dynamic maturity strategy and the diverse mutation strategy are introduced to VEGE, while the Latin hypercube sampling and embedded distance-based selection are employed in the RIME. Our proposed improved versions of VEGE and RIME are significantly better than the original version and competitive with the state-of-the-art MAs. For HHAs, we propose a novel evolutionary multi-mode slime mold optimization (EMSMO), where the low-level heuristics (LLHs) are inspired by the foraging behaviors of the slime mold, and the high-level component adopts the improvement-based selection function. Moreover, we introduce the surrogate-assisted estimation operator to the hyperheuristic framework and propose a surrogate ensemble-assisted hyper-heuristic algorithm (SEA-HHA). The experimental results and statistical analyses confirm the efficiency and effectiveness of our proposals