Lead and cadmium contents in cereals and pulses in north-eastern China

It is known that, unlike Japanese, Koreans or southern Chinese who depend on rice as a major source of energy for daily life, people in north-eastern China rely not only on rice, but on wheat and other cereals and to a lesser extent also on pulses. Cereal and pulse samples were collected from open markets in north-eastern China, and analyzed by inductively-coupled plasma spectrometry (ICP-MS) for two potentially hazardous heavy metals — lead (Pb) and cadmium (Cd). The average Pb level in cereals (31.3 ng Pb/g as a geometric mean) and that of pulses (25.7 ng Pb/g) were similar to each other with no significant difference. Among the cereals, Pb contents were higher in foxtail millet (54.3 ng/g) and lower in maize (35.4 ng Pb/g; grain and flour in combination), wheat flour (28.8 ng Pb/g) and rice flour (22.7 ng Pb/g). Lead levels in two important types of pulses, kidney bean and soybean (24.6 and 30.8 ng Pb/g, respectively), were comparable to the levels in rice and wheat. In contrast, Cd levels were substantially higher in pulses (55.7 ng Cd/g) than in cereals (9.2 ng Cd/g), and among the pulses, Cd in soybean (55.7 ng Cd/g) was significantly higher than that in kidney bean (23.8 ng Cd/g). The possible public health implication of the Pb and Cd levels, especially the high Pb level in foxtail millet (54.3 ng Pb/g) and the high Cd level in soybean (73.5 ng Cd/g), is discussed.     

Landslide disasters in Ehime Prefecture resulting from the July 2018 heavy rain event in Japan

In early July 2018, record heavy rainfalls caused enormous damage from western Japan to the Tokai region. In particular, Hiroshima, Okayama, and Ehime Prefectures suffered extensive human casualties and tremendous damage to housing units and the infrastructure due to landslides and river flooding. The authors conducted a series of reconnaissance operations and analyzed various kinds of data, including rainfall records, aerial photographs, official statistics of the disasters, and topographical and geological maps of Ehime Prefecture. In this report, the authors focus on the rainfall characteristics, geological background, and landslide statistics and distributions associated with the July 2018 events, and present examples of typical damage by geological belt. Based on this, they discuss several characteristics of the landslides, including the rainfall thresholds by geological belt, the characteristics of the runout distance of the debris flows, and the rainfall thresholds for landslide initiation in terms of the Soil Water Index (SWI). Based on an official database of a total of 413 landslides occurring in Ehime Prefecture and the authors’ newly developed database of 883 landslides in the southern part of the prefecture, several findings were obtained, for example, that slopes in the Shimanto Belt had a lower rainfall threshold for landslide initiation than slopes in the other two geological belts, namely, Sambagawa and Chichibu Belts.     

Benchmark solutions for natural convection in a cubic cavity using the high-order time-space method

Benchmark numerical solutions for a three-dimensional natural convection heat transfer problem in a cubical cavity are presented in this paper. The 3-D cavity has two differentially heated and isothermal vertical walls and also four adiabatic walls. The computations are conducted for three Rayleigh numbers of 10⁴, 10⁵ and 10⁶. The filled fluid is with air and the Prandtl number is fixed at 0.71. The computed results are efficiently obtained by using the time-space method, which was proposed by Saitoh (1991) as a highly efficient and fast solver for general heat transfer and fluid flow problems. In our computations, the high-accuracy finite differences of a fourth-order were employed for the spatial discretization of governing equations and boundary conditions. In addition the third-order backward finite difference was used in timewise discretization. The resultant converged flow and temperature characteristics are also presented. The spatial grid dependency of the solutions was examined on a uniform grid. In addition, the grid-independent benchmark solutions were obtained by Richardson extrapolation for three cases. The present benchmark solutions will be useful for checking the performance and accuracy of any numerical methodologies.     

Reduction in operator supervision time using a modified malfunction detection system with fuzzy inference in an industrial-scale fermentation of alkaline cellulase

A malfunction detection system based on fuzzy inference, in which a fermentation process is categorized into three states (normal, intermediate and abnormal) according to the computation of malfunction degree, was modified to reduce the supervision tasks required for an industrial-scale production of alkaline cellulase. The time lag of the culture, tau, was determined from the difference in the cumulated amount of CO2 evolved between the actual and standard values. By employing tau, the deviations of the actual values of process data (pH of broth and the amount of antifoaming agent supplied) from the standard values could be compensated for in terms of a delayed or forward effect in fermentation time. In the detection tests conducted for a series of 200 runs using the modified method, two runs and a single run were categorized as belonging to the abnormal and intermediate states, respectively, and all of the other runs were recognized to be in a normal state. As a result, the total supervision time for operators was reduced by the modification.     

Enhanced productivity of electrospun polyvinyl alcohol nanofibrous mats using aqueous N,N-dimethylformamide solution and their application to lipase-immobilizing membrane-shaped catalysts

Electrospun polyvinyl alcohol (PVA) nanofibrous non-woven fabrics have been widely used for cell and enzyme immobilization. Enhancement of the productivity of the material will further enlarge the versatility of them. In this study, a mixture of water and N,N-dimethylformamide (DMF) was used as a solvent of PVA. The productivity defined as ([1 - (amount of polymer which did not come in contact with the collector)/(amount of polymer ejected from the needle for 30 min)] × 100) of electrospun PVA fibers increased from 15 to 92% by increasing the content of DMF from 0 to 10 wt%. As a potential application of the electrospun PVA fibers prepared by the enhanced production system, we encapsulated Burkholderia cepacia (formerly, Pseudomonas cepacia) lipase in the fibers by including lipase powder in the PVA solution before electrospinning, and evaluated catalytic performance of the resultant fibrous catalysts in organic solvent. The lipase encapsulated in the PVA fibers produced from a solution of water and 10 wt% DMF showed a 1.5-fold increase in initial reaction rate in the transesterification of (S)-glycidol and vinyl butyrate to produce (S)-glycidyl butyrate than that encapsulated in the PVA fibers obtained from the solvent without DMF, i.e., water. These findings demonstrate the practicality of the proposed system to enhance the productivity of electrospun PVA fibrous matrices for extended applications of the resultant fibers including the usage as carriers enclosing lipase for reactions in organic solvents.     

Production of endothelial cell-enclosing alginate-based hydrogel fibers with a cell adhesive surface through simultaneous cross-linking by horseradish peroxidase-catalyzed reaction in a hydrodynamic spinning process

We developed an alginate-based hydrogel fiber enabling to enclose endothelial cells, degradable on-demand by alginate lyase, and having a cell adhesive surface. The hydrogel fiber was obtained by extruding an aqueous solution of 4% (w/v) alginate derivative possessing phenolic hydroxyl moieties (Alg-Ph) and horseradish peroxidase (HRP) into a flow of aqueous solution containing 0.3 mM H(2)O(2) and gelatin derivative possessing Ph moieties (Gelatin-Ph). In the process, cross-linking of Alg-Ph resulting in a hydrogel fiber and immobilization of Gelatin-Ph on the surface of the hydrogel fiber were simultaneously accomplished by an HRP-catalyzed cross-linking reaction between Ph moieties. The diameter of the hydrogel fiber and the quantity of immobilized Gelatin-Ph on the fiber were controllable by changing the flow rates of the solutions and the concentration of HRP in the Alg-Ph-containing solution, respectively. The viability of the human endothelial cells enclosed in the hydrogel fibers obtained by 10 s of flowing in the H(2)O(2)-containing solution was 87.1%. In addition, the cells harvested from the hydrogel fibers through degradation using alginate lyase grew on tissue culture dishes in the same fashion as the cells seeded by a conventional subculture protocol. Human smooth muscle cells adhered, grew and achieved confluence on the surface of the hydrogel fibers. By degrading the hydrogel fibers using alginate lyase, a tubular cell construct was successfully obtained.     

Glucose transporter mediation responsible for morphological changes of human epithelial cells on glucose-displayed surfaces

Cellular morphology is one of the important factors for coordinating cell signaling. In this study, the morphological variation via glucose transporter (GLUT)-mediated anchoring was investigated in the cultures of human mammary epithelial cells in the presence or absence of insulin on culture surfaces with the changed ratios of d- and l-glucose displayed. With increasing ratio of d-glucose displayed on the surfaces, the cells showed a stretched shape in the culture with 10 mug/cm(3) insulin, reaching the highest extent of cell stretching at 100%d-glucose display, whereas round cells were predominant at 0%d-glucose display. In the absence of insulin, on the other hand, the extent of cell stretching showed a concave profile in terms of the ratio of d-glucose displayed, the extent being highest at 50%d-glucose display. Blocking of integrin alpha(5)beta(1) or GLUTs1 and 4 on the cells using corresponding antibodies revealed that the primary mechanism for cell attachment was based on integrin-mediated binding, and that GLUTs1 and 4 contributed largely to morphological changes of cells. Confocal microscopy further revealed that GLUT4 localization occurred in response to d-glucose display as well as insulin addition. In the absence of insulin, GLUT4 spots were extensively observed in the cell body regardless of whether d-glucose was displayed or not. However, in the presence of insulin, the broad distribution of GLUT4 appeared on the basal and apical sides of cells at 100%d-glucose display, in contrast with its localization only on the apical side of cells at 0%d-glucose display. These results suggest that the quantitative balance between GLUTs on the cytoplasmic membrane and d-glucose displayed on a culture surface determines the cell morphology, as explained by the receptor saturation model.     

Estimator for generalization performance of machine learning model trained by biased data collected from multiple references

The data acquired in civil engineering tasks often involve high acquisition costs, and the available datasets tend to have a limited number of samples and are highly biased. To estimate the performance of machine learning models, k-fold cross-validation (k-CV) is widely used. However, if only limited data are available and the data distribution is biased, k-CV tends to overestimate the performance for practical applications. This study proposed a new estimator, leave one reference out and k-CV (LORO-k-CV), to determine the practical performance of machine learning models, that is, the generalization performance for population data in the target task, in case data are collected by multiple references resulting in biased data. LORO-k-CV is a combination of a new concept, LORO-CV, that estimates the performance in the extrapolation region of the training data without human intervention and k-CV, considering the ratio of the interpolation and extrapolation regions. The efficacy of LORO-k-CV was validated with its application to the regression task for the chloride-ion concentration of concrete structures. To more specifically demonstrate the advantages of LORO-k-CV in model construction, the feature selections were conducted using both k-CV and LORO-k-CV methods. These results revealed that LORO-k-CV can effectively construct a model with improved generalization performance even from the same data in cases where data are collected by multiple references, resulting in biased data.     

Applicability of machine learning to a crack model in concrete bridges

The growing demand for a more efficient maintenance of concrete bridges requires a model that tracks the deterioration of each bridge based on inspection data. Although it has been expected that machine learning could be applied to this problem, inspection data sparsely distributed over time are not suitable for machine learning in contrast to the continuous big data usually targeted. This study applies machine learning to a regression model of crack formation and propagation using inspection data to confirm the applicability. It includes the selection of the optimal algorithm, development of the model based on a novel methodology, and factor analysis using the model. Accordingly, the model was constructed by Gaussian process regression and it could appropriately extract the differences in the progress of crack damage due to multiple influential factors. The results demonstrate the excellent applicability of machine learning even to sparse data.     

Bloch Lines Constituting Antiskyrmions Captured via Differential Phase Contrast

Much scientific capital has been directed toward exotic magnetic spin textures called Bloch lines, that is, Néel-type line boundaries within domain walls, because their geometry promises high-density magnetic storage. While predicted to arise in high-anisotropy magnets, bulk soft magnets, and thin films with in-plane magnetization, Bloch lines also constitute magnetic antiskyrmions, that is, topological antiparticles of skyrmions. Most domain walls occur as Bloch-type or Néel-type, in which the magnetization rotates parallel or perpendicular to the domain wall across its profile, respectively. The Bloch lines’ Néel-type rotation and their minute size make them difficult to directly measure. This work utilizes differential phase contrast (DPC) scanning transmission electron microscopy (STEM) to measure the in-plane magnetization of Bloch lines within antiskyrmions emergent in a non-centrosymmetric Heusler magnet with D_2d symmetry, Mn_1.4Pt_0.9Pd_0.1Sn, in addition to Bloch-type skyrmions in an FeGe magnet with B20-type crystal structure to benchmark the DPC technique. Both in-focus measurement and identification of Bloch lines at the antiskyrmion's corners are provided.