A One-Dimensional Propagation of Shock Wave Supported by Atmospheric Millimeter-Wave Plasma

A shock wave supported by an atmospheric breakdown plasma caused by a high-power millimeter-wave beam was studied. The shadow graph image in a shock tube visualized the one-dimensional shock-wave generated by the millimeter-wave breakdown in atmosphere for the first time. It was revealed that a normal shock wave propagated through the tube at the constant velocity while it was detached from the ionization front of the plasma whenever the propagation velocity of the ionization front was supersonic or subsonic. And it was visually clarified that the atmospheric millimeter-wave breakdown had the combined structure of the normal shock wave and the heating region of the millimeter-wave plasma. The measured pressure of the shock front was as equal as the normal shock which propagated at measured Mach number.     

Comparative Analysis of DNA‐Binding Selectivity of Hairpin and Cyclic Pyrrole‐Imidazole Polyamides Based on Next‐Generation Sequencing

Many long pyrrole‐imidazole polyamides (PIPs) have been synthesized in the search for higher specificity, with the aim of realizing the great potential of such compounds in biological and clinical areas. Among several types of PIPs, we designed and synthesized hairpin and cyclic PIPs targeting identical sequences. Bind‐n‐Seq analysis revealed that both bound to the intended sequences. However, adenines in the data analyzed by the previously reported Bind‐n‐Seq method appeared to be significantly higher in the motif ratio than thymines, even though the PIPs were not expected to distinguish A from T. We therefore examined the experimental protocol and analysis pipeline in detail and developed a new method based on Bind‐n‐Seq motif identification with a reference sequence (Bind‐n‐Seq‐MR). High‐throughput sequence analysis of the PIP‐enriched DNA data by Bind‐n‐Seq‐MR presented A and T comparably. Surface plasmon resonance assays were performed to validate the new method.     

Experimental tests of slope failure due to rainfalls using 1g physical slope models

In order to mitigate the damage due to sediment disasters, knowledge about how slopes fail due to rainfall is indispensable. The main objectives of this paper were to investigate experimentally the effects of surface sand layer density and rainfall intensity on the slop failures due to rainfalls. We conducted a series of experimental tests using 1g physical slope models constructed of Kasumigaura sand and a silt soil named DL clay for the permeable residual surface layer and the firm rock foundation, respectively. A total of nine cases with different combinations of surface sand layer densities and rainfall intensities was tested. Two types of failure: surface slide failure and retrogressive failure, were observed depending on the rainfall intensity and the surface sand layer density. The following mechanism of failure was accounted. At first some sands, which contained a lot of accumulated rainwater, flowed out (flowslide) at the slope toes. The flow slides may be due to the reductions of effective stresses as a result. When a surface slide failure occurred, most of the PWP (pore water pressure) values were still negative but the whole sand layers were almost at the saturation condition. In the case of retrogressive failures, seepage surfaces rose up to higher positions and excess PWPs appeared under the seepage surfaces. This difference of generation mechanism of PWP values may be the deciding factor in the difference in the type of failure.     

Advancing Small‐Molecule‐Based Chemical Biology with Next‐Generation Sequencing Technologies

Next‐generation‐sequencing (NGS) technologies enable us to obtain extensive information by deciphering millions of individual DNA sequencing reactions simultaneously. The new DNA‐sequencing strategies exceed their precursors in output by many orders of magnitude, resulting in a quantitative increase in valuable sequence information that could be harnessed for qualitative analysis. Sequencing on this scale has facilitated significant advances in diverse disciplines, ranging from the discovery, design, and evaluation of many small molecules and relevant biological mechanisms to maturation of personalized therapies. NGS technologies that have recently become affordable allow us to gain in‐depth insight into small‐molecule‐triggered biological phenomena and empower researchers to develop advanced versions of small molecules. In this review we focus on the overlooked implications of NGS technologies in chemical biology, with a special emphasis on small‐molecule development and screening.     

Role of inorganic chlorides in formation of PCDDs, PCDFs, and coplanar PCBs from combustion of plastics, newspaper, and pulp in an incinerator

The total amounts of dioxins found in exhaust gases from combustion of polyethylene (PE), polystyrene (PS), and poly(ethylene terephthalate) (PET) with approximately 3% (w/ w) NaCl were 6.07, 17.7, and 28.9 ng/g, respectively. Plastics containing benzene rings produced more dioxins than plastic containing no benzene ring. The amounts of dioxin formed in the exhaust gases from the combustion of newspapers impregnated with CaCl2, KCl, and NaCl were 18.6, 28.6, and 49.0 ng/g, respectively. Dioxin formation was associated with the bond energy between metal atom and chlorine atom. When newspapers impregnated with four different amounts of NaCl were combusted, the highest NaCl content newspaper (chlorine content 4.08%, w/w; lignin content 19.8%, w/w) produced the greatest amount of dioxins (174 ng/g). Pulp with NaCl (chlorine content 4.25%, w/w; lignin content 0.69%, w/w) produced more dioxins (6.71 ng/g) than pulp alone (0.799 ng/g) did upon combustion. The lignin content in a combustion sample correlated with the amount of dioxin formation. The results exhibited that combustion conditions with low CO concentration (<2 ppm) produced much less dioxins than conditions with high CO concentration (159 ppm).     

Debittering of enzymatic hydrolysates using an aminopeptidase from the edible basidiomycete Grifola frondosa

Bitter peptide solutions, prepared by the enzymatic hydrolysis of soy protein and milk casein, were treated with an aminopeptidase from the edible basidiomycete Grifola frondosa. As the incubation time elapsed, the amount of free amino acids released increased and the bitterness of the enzyme reaction mixtures decreased. However, the debittering of the milk casein hydrolysate by the aminopeptidase was less effective than that observed for the soy protein hydrolysate. Hydrophobic amino acids such as valine, leucine, phenylalanine, tyrosine, and isoleucine were preferentially released from the bitter solutions by the action of the aminopeptidase.     

Formation of PCDDs, PCDFs, and coplanar PCBs from polyvinyl chloride during combustion in an incinerator

Exhaust gases from the combustion of poly(vinyl chloride) (PVC), polyethylene (PE), polystyrene (PS), poly(ethylene terephthalate) (PET), and theirvarious mixtureswere analyzed for PCDDs, PCDFs, and coplanar PCBs by gas chromatography/mass spectrometry (GC/MS) in order to investigate the role of PVC in these chlorinated compounds. Total amounts of dioxins (PCDDs + PCDFs) found in the samples were 11.7 ng/g PE alone, 1.17 ng/g from PS alone, 25.3 ng/g from PET alone, 448 ng/g from PE with PVC, 140 ng/g from PS with PVC, 126 ng/g from PET with PVC, 824 ng/g from PVC alone under low-CO level, and 8,920 ng/g from PVC alone under high-CO level. CO level in high-CO level condition was 880 ppm which was 20 times greater than that in low-CO level condition. Formation of coplanar PCBs ranged from 0.095 ng/g (PE alone) to 77 ng/g (PVC alone under high-CO level). There is a clear correlation between dioxin formation and chloride content. PCDFs composed 80% (PET + PVC)--98% (PET alone) of the total dioxins formed in the exhaust gases. The results indicate that PVC contributes significantly to the formation of PCDDs, PCDFs, and coplanar PCBs from mixtures of plastics upon combustion.     

Behaviour of cobalt infiltration and abnormal grain growth during sintering of diamond on cobalt substrate

The infiltration behaviour of molten cobalt into a diamond powder compact was examined when the latter was placed on a cobalt disc and held at high pressure of 5.8 GPa and high temperature of 1350 to 1500° C. The larger the grain size of the starting diamond powder and the higher the holding temperature, the more easily cobalt infiltrated into the diamond compact. The infiltration is considered to occur because of the negative pressure in the voids formed between diamond grains. Although diamond powder was consolidated in this process of cobalt infiltration, abnormal grain growth was also observed in the boundary between cobalt and diamond compact because of the dissolution and precipitation process of the compact into molten cobalt.On leave from Chengdu University of Science and Technology, Chengdu, China.     

Cupric ion-dependent inhibition of lysosomal acid cholesteryl ester hydrolase in the presence of hydroxylamine

In the presence of hydroxylamine or ascorbic acid, the inhibitory effects of Cu²⁺ on lysosomal acid cholesteryl ester hydrolase (acid CEH) partially purified from rat liver were studied. Hydroxylamine stimulated the inhibition of acid CEH activity by Cu²⁺ but not that by Zn²⁺, Fe²⁺, Co²⁺, Mn²⁺, Ca²⁺, Mg²⁺ and Hg²⁺. This Cu²⁺-dependent inhibition of acid cholesterol ester hydrolase (CEH) activity was completely prevented by ethylenediamine tetraacetic acid (EDTA), EGTA and o-phenanthroline, a chelator with a stability constant for Cu²⁺, and also by sulfhydryl agents and cytoplasmic reducing agents such as cysteine, glutathione and mercaptoethanol. In addition, the stimulative effects of hydroxylamine on Cu²⁺-dependent inhibition were maintained even after preincubation of Cu²⁺ with hydroxylamine. On the other hand, ascorbic acid was found to replace the stimulation by hydroxylamine of the Cu²⁺-dependent inhibition of acid CEH activity but the effects of ascorbic acid progressively became smaller with prolongation of the preincubation time. Moreover, addition of chemical radical scavengers to the reaction mixture did not prevent the Cu²⁺-dependent inhibition of acid CEH activity in the presence of ascorbic acid. These results suggest that Cu²⁺ causes inhibition of lysosomal acid CEH activity through the formation of Cu¹⁺ in a reductive medium.     

A new method for generating group constants for analysis of blanket parameters of HCLWR with Monte Carlo method

The preliminary analysis of natural uranium blanket region at the KUCA was carried out with continuous energy monte carlo method and group energy monte carlo method. From the results obtained, it is clear that group constants weighted with scalar neutron spectrum cannot predict the transitory effect of the forward biased on neutron angular distribution. It is suggested that the direction-dependent group constants have to be used to predict the reaction rate in the blanket region accurately.