This paper reports on the behavior of shock triple points on the detonation wave propagating in the rectangular tube, which is obtained from the experimental observation and numerical analysis. Used ...gas mixtures are the equimolar gas mixture of acetylene and oxygen in the experiment, and the stoichiometric hydrogen and oxygen in the numerical analysis. However, if there are the specific number of shock triple points in the tube, the numerical analysis using finite difference method which is composed of semi-implicit MacCormack TVD scheme can reproduce the propagation behavior obtained by experiment. Therefore, the propagation mode of detonation is identified by geometry of emission points and emission trajectories of the experimental observation. And then, the detailed propagation mechanism of its detonation which is difficult to observe in the experiment has been revealed.
The present study describes the synthesis of novel polypeptides containing O‐phospho‐L‐threonine Thr(PO3H2) and L‐aspartic acid. Random copolypeptides copolyThr(PO3H2)XAspY (X:Y = 25:75, 50:50, ...75:25), were conventionally prepared by copolymerization of Thr(PO3Ph2) N‐carboxyanhydride (NCA) and Asp(OBzl) NCA followed by deprotection of the phenyl and benzyl groups by catalytic hydrogenolysis over PtO2. Polycondensation of the protected peptide p‐nitrophenyl esters Thr(PO3Ph2)Z‐Asp(OBzl)‐ONp and subsequent deprotection yielded the sequential polypeptides polyThr(PO3H2)Z‐Asp (Z = 1–4). By using the synthetic polypeptides, their effects on the growth of CaCO3 crystals were examined. In the polyThr(PO3H2)Z‐Asp/CaCO3 systems, brushlike calcite and spherical vaterite were formed, with the former being found at Ca2+/Res ratios of ≥180, ≥140, ≥120, and ≥100 for Z = 1, 2, 3, and 4, respectively. These results indicate that an increase of Thr(PO3H2) residues in the repetitive unit induces the characteristic brushlike calcite, a fact indicating that Thr(PO3H2) residues can modify the CaCO3 crystal morphology.
The objective of this study was to determine the factor of xylem maturation in Eucalyptus grandis W. Hill ex Maid. planted in four different latitudes and climatic divisions of South America, based ...on the pattern of the radial distribution of fiber length. In the plantation closest to the equator, the extent of juvenile wood is determined by distance from the pith and is consistent from tree to tree, regardless of growth rate. In contrast, in the plantation farthest from the equator, xylem maturation is controlled by cambial age and varies from tree to tree, depending on growth rate. To produce as much mature wood as early as possible in E. grandis planted closer to the equator, lateral growth should be accelerated from the early growing stage, because the formation of mature wood starts after a certain trunk diameter is reached. Conversely, in plantations far from the equator, it is necessary to first arrest lateral growth at an early growth stage and then accelerate lateral growth after a certain cambium age is reached.
Celotno besedilo
Dostopno za:
BF, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Unspliced HIV-1 RNAs function as messenger RNAs for Gag or Gag-Pol polyproteins and progeny genomes packaged into virus particles. Recently, it has been reported that fate of the RNAs might be ...primarily determined, depending on transcriptional initiation sites among three consecutive deoxyguanosine residues (GGG tract) downstream of TATA-box in the 5' long terminal repeat (LTR). Although HIV-1 RNA transcription starts mostly from the first deoxyguanosine of the GGG tract and often from the second or third deoxyguanosine, RNAs beginning with one guanosine (G1-form RNAs), whose transcription initiates from the third deoxyguanosine, were predominant in HIV-1 particles. Despite selective packaging of G1-form RNAs into virus particles, its biological impact during viral replication remains to be determined. In this study, we revealed that G1-form RNAs are primarily selected as a template for provirus DNA rather than other RNAs. In competitions between HIV-1 and lentiviral vector transcripts in virus-producing cells, approximately 80% of infectious particles were found to generate provirus using HIV-1 transcripts, while lentiviral vector transcripts were conversely selected when we used HIV-1 mutants in which the third deoxyguanosine in the GGG tract was replaced with deoxythymidine or deoxycytidine (GGT or GGC mutants, respectively). In the other analyses of proviral sequences after infection with an HIV-1 mutant in which the GGG tract in 3' LTR was replaced with TTT, most proviral sequences of the GGG-tract region in 5' LTR were found to be TTG, which is reasonably generated using the G1-form transcripts. Our results indicate that the G1-form RNAs serve as a dominant genome to establish provirus DNA.IMPORTANCESince the promoter for transcribing HIV-1 RNA is unique, all viral elements including genomic RNA and viral proteins have to be generated by the unique transcripts through ingenious mechanisms including RNA splicing and frameshifting during protein translation. Previous studies suggested a new mechanism for diversification of HIV-1 RNA functions by heterogeneous transcriptional initiation site usage; HIV-1 RNAs whose transcription initiates from a certain nucleotide were predominant in virus particles. In this study, we established two methods to analyze heterogenous transcriptional initiation site usage by HIV-1 during viral infection and showed that RNAs beginning with one guanosine (G1-form RNAs), whose transcription initiates from the third deoxyguanosine of the GGG tract in 5' LTR, were primarily selected as viral genome in infectious particles and thus are used as a template to generate provirus for continuous replication. This study provides insights into the mechanism for diversification of unspliced RNA functions and requisites of lentivirus infectivity.
Purpose: The purpose of this study was to investigate the injection pressure reduction effect of the novel indwelling needle (Becton, Dickinson and Company). Method: We evaluated the period of 651 ...patients who underwent dynamic computed tomography. We compared the maximum injection pressure. The contrast medium was administered at 320, 350, and 370 mgI/ml. Result: The maximum injection pressure of the novel indwelling needle in 22 G was decreased 10% compared with SC5 in all contrast media. The maximum injection pressure of BDN in 20 G decreases 8% compared with SC5 at 370 mgI/ml, but there was no reduction at 320 mgI/ml and 350 mgI/ml. Conclusion: Our analysis demonstrated that BDN significantly reduced the injection pressure especially in 22 G and using high concentration contrast medium in 20 G.
To investigate in detail the mechanical interactions and associations between cellulose microfibrils (CMFs) and the matrix substance, we measured the dimensional changes in cellulose crystals in wood ...cell walls after different treatments. The transverse expansion of CMFs observed after hygrothermal treatment and subsequent drying suggests that the matrix substance compresses the CMFs transversely under green conditions. However, as heat treatment breaks or weakens the association of the CMFs and the matrix substance, under hygrothermal treatment and drying at high temperature the matrix substance cannot compress the CMFs in the direction of the chain.
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