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Background and Objectives: It is known that any wild‐type varieties of cereals so far examined have A‐type starch crystals in their endosperm whereas their starch branching enzyme 2b (be2b) mutants that are usually referred to as amylose‐extender (ae) mutants produce B‐type starch crystals. The present study aimed to examine the structural features of amylopectin which are responsible for the A‐type or B‐type crystalline allomorphs of starch granules by using starches in wild‐type japonica and indica rice varieties and their be2b (ae) mutants. Findings: The average length of chains of A‐type amylopectin was markedly shorter than that of B‐type amylopectin. It was also thought that A‐type amylopectin had two types of branches, namely the first branches were formed mainly by BEI in the basal region of the cluster and the second branches were synthesized specifically by BEIIb inside the cluster. These differences caused the average length of double helices formed by cluster constituent chains to be shorter in wild‐types than that in their be2b mutants, and these differences changed the crystalline allomorph of starch granules to B‐type in the mutants from A‐type in their wild‐types, as examined by wide angle X‐ray diffraction and sum frequency generation spectroscopy. Conclusions: Combined with these observations and calculations of chain‐length of hypothetical A chains in four types of amylopectin molecules, it was concluded that both the average length of external segments of cluster chains and the formation of the second branches inside the cluster greatly affect the crystal types of starch granules. Significance and Novelty: The novel findings in the present study can provide new insights into the structural features of amylopectin which determine the A‐type or B‐type crystalline allomorph of starch granules of cereals. [ABSTRACT FROM AUTHOR]

Purpose: The efficiency of protective equipment for the brain has not been verified at the left anterior oblique (LAO) position, which is commonly used in clinical procedures. The purpose of this study was to investigate radiation exposure of the brain in interventional radiology (IR) and the shielding ability of a new protective flap. Methods: We made a flap that combined a protective cap with a left lateral face shield. The flap was made of tungsten‐containing rubber (TCR). An anthropomorphic head phantom was placed at the physician's position, and air kerma rates (μGy/min and μGy/15s) were measured by electronic dosimeter at three locations: the surface of the left side of the head, and the left and right temporal lobes with the protective cap and the flap in fluoroscopy and cine modes. The X‐ray tube was at the lower left side of the physician, and its angles were LAO60 and LAO60CAU40. The tube voltage (95–125 kV), tube current (4.7–732 mA), and air kerma rate (27.8–1078 mGy/min) were automatically adjusted by the X‐ray system. We obtained the cap and the flap shielding efficiencies. Results: In cine mode at LAO60CAU40, the shielding efficiencies on the surface of the left side of the head and left temporal lobe with the cap were 92.6% and 5.1%, respectively, and the corresponding shielding efficiencies with the flap were 92.5% and 86.1%, respectively. The flap can reduce radiation exposure of the brain more than the cap alone. Conclusions: At the left anterior oblique in interventional radiology, the flap can reduce exposure to the brain. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to compare the dose–volume parameters and regression scatter plots of the iteratively improved RapidPlan (RP) models, specific knowledge‐based planning (KBP) models, in volumetric‐modulated arc therapy (VMAT) for prostate cancer over three periods. Methods: A RP1 model was created from 47 clinical intensity‐modulated radiation therapy (IMRT)/VMAT plans. A RP2 model was created to exceed dosimetric goals which set as the mean values +1SD of the dose–volume parameters of RP1 (50 consecutive new clinical VMAT plans). A RP3 model was created with more strict dose constraints for organs at risks (OARs) than RP1 and RP2 models (50 consecutive anew clinical VMAT plans). Each RP model was validated against 30 validation plans (RP1, RP2, and RP3) that were not used for model configuration, and the dose–volume parameters were compared. The Cook's distances of regression scatterplots of each model were also evaluated. Results: Significant differences (p < 0.05) between RP1 and RP2 were found in Dmean (101.5% vs. 101.9%), homogeneity index (3.90 vs. 4.44), 95% isodose conformity index (1.22 vs. 1.20) for the target, V40Gy (47.3% vs. 45.7%), V60Gy (27.9% vs. 27.1%), V70Gy (16.4% vs. 15.2%), and V78Gy (0.4% vs. 0.2%) for the rectal wall, and V40Gy (43.8% vs. 41.8%) and V70Gy (21.3% vs. 20.5%) for the bladder wall, whereas only V70Gy (15.2% vs. 15.8%) of the rectal wall differed significantly between RP2 and RP3. The proportions of cases with a Cook's distance of <1.0 (RP1, RP2, and RP3 models) were 55%, 78%, and 84% for the rectal wall, and 77%, 68%, and 76% for the bladder wall, respectively. Conclusions: The iteratively improved RP models, reflecting the clear dosimetric goals based on the RP feedback (dose–volume parameters) and more strict dose constraints for the OARs, generated superior dose–volume parameters and the regression scatterplots in the model converged. This approach could be used to standardize the inverse planning strategies. [ABSTRACT FROM AUTHOR]

In this paper, ablation polymer was studied to improve the thermal interrupting performance of an SF6 gas circuit breaker. One kind of polymer was used as the ablation polymer on the basis of the specific constraint conditions for SF6 gas circuit breakers, such as not including hydrogen, and its ablation characteristics were investigated. Furthermore, the dominant factor of that polymer ablation was discussed by comparing ablated mass characteristics between the ablation polymer and polytetrafluoroethylene, which is widely used as the nozzle material of an SF6 gas circuit breaker. © 2020 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

Characteristics of PTFE ablation due to SF6 arc exposure were studied to predict the ablated mass of PTFE nozzle in high‐voltage circuit breaker. From the measurement of the ablated mass, the predominant factor of the PTFE ablation was revealed as a radiation power of SF6 arc. Subsequently, the radiation power absorbed in PTFE was formulated on the basis of the radiation transfer property and the arc physics. The formulation for the prediction of the PTFE ablated mass was established with the formulated radiation power and the measured masses. Finally, the validity of the PTFE ablated mass prediction was shown from the results of the error verification with the measured masses. [ABSTRACT FROM AUTHOR]

•Reserve starch is an important plant product but the actual biosynthetic process is not yet fully understood. •Potato ( Solanum tuberosum) tuber discs from various transgenic plants were used to analyse the conversion of external sugars or sugar derivatives to starch. By using in vitro assays, a direct glucosyl transfer from glucose 1-phosphate to native starch granules as mediated by recombinant plastidial phosphorylase was analysed. •Compared with labelled glucose, glucose 6-phosphate or sucrose, tuber discs converted externally supplied [14C]glucose 1-phosphate into starch at a much higher rate. Likewise, tuber discs from transgenic lines with a strongly reduced expression of cytosolic phosphoglucomutase, phosphorylase or transglucosidase converted glucose 1-phosphate to starch with the same or even an increased rate compared with the wild-type. Similar results were obtained with transgenic potato lines possessing a strongly reduced activity of both the cytosolic and the plastidial phosphoglucomutase. Starch labelling was, however, significantly diminished in transgenic lines, with a reduced concentration of the plastidial phosphorylase isozymes. •Two distinct paths of reserve starch biosynthesis are proposed that explain, at a biochemical level, the phenotype of several transgenic plant lines. [ABSTRACT FROM AUTHOR]

• Common reed ( Phragmites australis) is a well known salt-tolerant plant and it is suggested that reeds recover Na+ in the xylem sap of the shoot base (basal part of the shoot), store it temporarily in the shoot base, release it into the phloem sap, and then retranslocate it to the roots. • To investigate whether Na+ is retained in the shoot base of reeds, confocal laser scanning microscope (CLSM) observations were conducted using an intracellular Na+-specific fluorescent probe. The CLSM observations revealed that reeds produced a large number of the starch granules at the shoot base when salt-stressed, and that the fluorescence indicating the location of intracellular free Na+ was observed in the same position as the starch granules. • The Na content of starch granules was considerably greater than that of the shoot base, whereas the potassium (K) contents of the granules was only slightly greater than that of the shoot base. • Reeds produced Na+-binding starch granules in the parenchyma cells of the shoot base when salt-stressed; these starch granules may decrease intracellular free Na+. It is proposed that the site-specific production of Na+-binding starch granules constitutes a novel salt tolerance mechanism. [ABSTRACT FROM AUTHOR]

Amyloplast-targeted green fluorescent protein (GFP) was used to monitor amyloplast division and starch granule synthesis in the developing endosperm of transgenic rice. Two classical starch mutants,sugaryandshrunken, contain reduced activities of isoamylase1 (ISA1) and cytosolic ADP-glucose pyrophosphorylase, respectively. Dividing amyloplasts in the wild-type andshrunkenendosperms contained starch granules, whereas those insugaryendosperm did not contain detectable granules, suggesting that ISA1 plays a role in granule synthesis at the initiation step. The transition from phytoglycogen tosugary-amylopectin was gradual in the boundary region between the inner and outer endosperms ofsugary.These results suggest that the synthesis ofsugary-amylopectin and phytoglycogen involved a stochastic process and that ISA1 activity plays a critical role in the stochastic process in starch synthesis in rice endosperm. The reduction of cytosolic ADP-glucose pyrophosphorylase activity inshrunkenendosperm did not inhibit granule initiation but severely restrained the subsequent enlargement of granules. Theshrunkenendosperm often developed pleomorphic amyloplasts containing a large number of underdeveloped granules or a large cluster of small grains of amyloplasts, each containing a simple-type starch granule. Although constriction-type divisions of amyloplasts were much more frequent, budding-type divisions were also found in theshrunkenendosperm. We show that monitoring GFP in developing amyloplasts was an effective means of evaluating the roles of enzymes involved in starch granule synthesis in the rice endosperm. [ABSTRACT FROM AUTHOR]

When the starch branching enzyme IIb (BEIIb) gene was introduced into a BEIIb-defective mutant, the resulting transgenic rice plants showed a wide range of BEIIb activity and the fine structure of their amylopectins showed considerable variation despite having the two other BE isoforms, BEI and BEIIa, in their endosperm at the same levels as in the wild-type. The properties of the starch granules, such as their gelatinization behaviour, morphology and X-ray diffraction pattern, also changed dramatically depending on the level of BEIIb activity, even when this was either slightly lower or higher than that of the wild-type. The over-expression of BEIIb resulted in the accumulation of excessive branched, water-soluble polysaccharides instead of amylopectin. These results imply that the manipulation of BEIIb activity is an effective strategy for the generation of novel starches for use in foodstuffs and industrial applications. [ABSTRACT FROM AUTHOR]

Regarding a PTFE (polytetrafluoroethylene) nozzle ablation due to arc radiation exposure in SF6 circuit‐breaker, the ablated mass of the nozzle was formulated as a function of an arc current and an internal radius of the nozzle surface considering the radiation power absorbed on the surface. Furthermore, this formulation contributed to subsequent development of calculation method for evaluating gas pressure rise process during current interruption. And, verification experiments of the calculation method were performed with a model SF6 circuit‐breaker equipped a puffer chamber. Calculation results derived from the developed calculation method showed good agreement with measured gas pressure rise process. On the basis of the verified results, a discussion was made to explain pressure rise mechanism. [ABSTRACT FROM AUTHOR]