Effects of Sampling Tube Geometry on Soft Clayey Sample Quality Evaluated by Nondestructive Methods

Sample disturbance caused by difference in sampling tube geometry was evaluated by two nondestructive methods: the measurement of the residual effective stress (p_r') by ceramic disc; and the use of the bender element to ascertain the shear wave velocity (V_s), and thus the maximum shear modulus (G_BE). Samples were measured under atmosphere, i.e., not under confined stress conditions. The soil samples were obtained from two sources: reconstituted Kasaoka clay prepared in the laboratory, and at the test site at Takuhoku, Hokkaido, Japan. Samplers with different geometrical designs, referring to the Japanese standard stationary piston sampler, were used for the model ground and field sampling. The geometrical effects of the sampling tube, for example, the thickness of the tube wall, the edge angle, and the existence of a piston were carefully examined. The quality of the samples taken with different samplers was evaluated by p_r' and G_BE, values which were normalized by the in situ vertical effective stress (σ'_vo) and G_f measured by the seismic cone test in the field. It was found from these studies that p_r'/σ'_vo and G_BE/G_f vary considerably due to the geometry of the sampler, with the edge angle of sampling tubes being the most important feature in obtaining high quality samples. The wall thickness, and thus, the area ratio of the sampler is not critical to the sample quality if the edge angle is sharp enough. The existence of the piston does not significantly influence the sample quality in field samples. Furthermore, the correlation between G_BE and p_r' was also investigated, and it was found that the two parameters are strongly dependent.     

Regional forecasts of photovoltaic power generation according to different data availability scenarios: a study of four methods

The development of methods to forecast photovoltaic (PV) power generation regionally is of utmost importance to support the spread of such power systems in current power grids. The objective of this study is to propose and to evaluate methods to forecast regional PV power 1 day ahead of time and to compare their performances. Four forecast methods were regarded, of which two are new ones proposed in this study. Together, they characterize a set of forecast methods that can be applied in different scenarios regarding availability of data and infrastructure to make the forecasts. The forecast methods were based on the use of support vector regression and weather prediction data. Evaluations were performed for 1 year of hourly forecasts using data of 273 PV systems installed in two adjacent regions in Japan, Kanto, and Chubu. The results show the importance of selecting the proper forecast method regarding the region characteristics. For Chubu, the region with a variety of weather conditions, the forecast methods based on single systems' forecasts and the one based on stratified sampling provided the best results. In this case, the best annual normalized root mean square error (RMSE) and mean absolute error (MAE) were 0.25 and 0.15 kWh/kWh_avg, respectively. For Kanto, with homogeneous weather conditions, the four methods performed similarly. In this case, the lowest annual forecast errors were 0.33 kWh/kWh_avg for the normalized RMSE and 0.202 kWh/kWh_avg for the normalized MAE. Copyright © 2014 John Wiley & Sons, Ltd.     

Reactive processing of thermoset/thermoplastic blends: A potential for injection molding

Poly(2,6-dimethyl-1,4-phenylene ether) (PPE) is an engineering plastic with high heat distortion temperature. Melt processing of neat PPE is usually accompanied with thermal degradation. The degradation problem is solved by blending with polystyrene to reduce the processing temperature. We propose an alternative using triallylisocyanurate (TAIC). TAIC is a low viscosity liquid that can be cured by peroxide, e.g. α,α′-bis(t-butylperoxy-m-isopropyl)benzene (PBP), to provide a thermoset. The PPE/TAIC mixture was shown to have the upper critical solution temperature (UCST) type phase behavior. At the single-phase regime above UCST and below the cure temperature (∼180°C for PBP), the mixture had a low viscosity, less viscous than a conventional thermoplastic such as PC and PP. That is, a nice window for injection molding was available, e.g., at 100°C to 160°C for a 50/50 blend. After injecting into a hot mold set at cure temperature, the blend cured in a short time (∼80% conversion in 5 min). Then the molded and partly cured material kept its shape and dimensions during post-cure in a hot chamber at higher temperature (e.g. 250°C). Using transmission electron microscopy and dynamic mechanical analyses, it was shown that the cured blend had a bicontinuous two-phase structure with periodic spacings of ∼30 nm, suggesting a structure formation via a spinodal decomposition driven by the increase in molecular weight of TAIC during cure. The cured material showed excellent flexural strength and high chemical resistance.     

Mutation Analysis of Radioresistant Early-Stage Cervical Cancer

Radiotherapy is a definitive treatment for early-stage cervical cancer; however, a subset of this disease recurs locally, necessitating establishment of predictive biomarkers and treatment strategies. To address this issue, we performed gene panel-based sequencing of 18 stage IB cervical cancers treated with definitive radiotherapy, including two cases of local recurrence, followed by in vitro and in silico analyses. Simultaneous mutations in KRAS and SMAD4 (KRAS^mt/SMAD4^mt) were detected only in a local recurrence case, indicating potential association of this mutation signature with radioresistance. In isogenic cell-based experiments, a combination of activating KRAS mutation and SMAD4 deficiency led to X-ray resistance, whereas either of these factors alone did not. Analysis of genomic data from 55,308 cancers showed a significant trend toward co-occurrence of mutations in KRAS and SMAD4. Gene Set Enrichment Analysis of the Cancer Cell Line Encyclopedia dataset suggested upregulation of the pathways involved in epithelial mesenchymal transition and inflammatory responses in KRAS^mt/SMAD4^mt cancer cells. Notably, irradiation with therapeutic carbon ions led to robust killing of X-ray-resistant KRAS^mt/SMAD4^mt cancer cells. These data indicate that the KRAS^mt/SMAD4^mt signature is a potential predictor of radioresistance, and that carbon ion radiotherapy is a potential option to treat early-stage cervical cancers with the KRAS^mt/SMAD4^mt signature.     

An Innovative Customized Biomimetic Hydrogel for Drug Screening Application Potential: Biocompatibility and Cell Invasion Ability

The ability of Pluronic F127 (PF127) conjugated with tetrapeptide Gly-Arg-Gly-Asp (GRGD) as a sequence of Arg-Gly-Asp (RGD) peptide to form the investigated potential hydrogel (hereafter referred to as 3DG bioformer (3BE)) to produce spheroid, biocompatibility, and cell invasion ability, was assessed in this study. The fibroblast cell line (NIH 3T3), osteoblast cell line (MG-63), and human breast cancer cell line (MCF-7) were cultured in the 3BE hydrogel and commercial product (Matrigel) for comparison. The morphology of spheroid formation was evaluated via optical microscopy. The cell viability was observed through cell counting Kit-8 assay, and cell invasion was investigated via Boyden chamber assay. Analytical results indicated that 3BE exhibited lower spheroid formation than Matrigel. However, the 3BE appeared biocompatible to NIH 3T3, MG-63, and MCF-7 cells. Moreover, cell invasion ability and cell survival rate after invasion through the 3BE was displayed to be comparable to Matrigel. Thus, these findings demonstrate that the 3BE hydrogel has a great potential as an alternative to a three-dimensional cell culture for drug screening applications.     

GPC Profile Change of Potato Starch with Extrusion Processing

Native potato starch (moisture content 15%) was treated by twin screw extruder under four operating conditions with varying barrel temperatures (110°C–230°C). These modified starch samples were compared to native and drum-dried starch. Starch sample solution for gel chromatography was prepared by the three methods (acidic, alkaline, and neutral methods). They were subjected to gel chromatography on Toyopearl HW-75, and some difference was found among the three gel chromatographic patterns obtained from the same starch solution. This discrepancy among GPC patterns suggests formation of some types of anhydro-bonds between chains of amylopectin and or amylose in the extrusion process. Elevating barrel temperature increases degree of depolymerization. The size of fragments formed with the treatment is bigger than that of oligosaccharides but smaller than that of amylose.     

Speciation of selenium in selenium-enriched seeds,buckwheat (<Emphasis Type="Italic">Fagopyrum esculentum</Emphasis> Moench) and quinoa (<Emphasis Type="Italic">Chenopodium quinoa</Emphasis> Willdenow)

Buckwheat (Fagopyrum esculentum Moench) and quinoa (Chenopodium quinoa Willdenow) are widely used as food ingredients. The nutritional characteristics of these plants, i.e., high contents of proteins and amino acids suggest that selenium (Se) is preserved as selenoamino acid derivatives, in particular, selenomethionine (SeMet) in proteins, similar to selenized yeast. Therefore, buckwheat and quinoa are expected to be a good nutritional source of Se. Selenized buckwheat and quinoa were cultivated on Se-fortified soil using sparingly soluble Se salts, such as barium selenate and barium selenite. Se concentration in the edible parts of these plants was determined, and Se extraction efficiency with enzyme or alkali was evaluated. In addition, the chemical species of Se in the low molecular weight fraction of these plants were determined by HPLC-ICP-MS. Total Se concentrations in the edible parts of selenized buckwheat and quinoa were 170.4 ± 2.9 μg/g and 102.7 ± 2.4 μg/g wet weight, respectively. Thus, these selenized seeds were found to be Se accumulators. The results indicate that Se in selenized buckwheat exists mainly as SeMet, while Se in selenized quinoa exists not only as SeMet but also as selenate (Se(VI)) and non-protein forms.