Continuous organic synthesis in water around micro-orifices after flows.

Water flows through micro-orifices are important because they occur in various fields, such as biology, medical science, chemistry, and engineering. We have reported in previous work that organic matter was generated in micro-orifices after water flowed through the orifice, and we proposed that the organic matter was synthesized from nonorganic materials, including CO2 and N2 dissolved in water from air, and water via the action of hydroxyl radicals produced by the flow through the micro-orifice. In the present study, we examined whether organic materials are produced in the water outside of the orifices in addition to that in the orifice. We used the decrease in water volume to measure the organic synthesis because water should be consumed during the synthesis, and thus the decrease in water volume should reflect the organic synthesis. We let ultrapure water containing dissolved air flow through a micro-orifice as a pre-flow, we stopped the flow, and then we measured the volume of water enclosed in the mount in which the micro-orifice was set over more than 100 h. The volume of water decreased gradually and substantially over time. We used Raman and infrared spectroscopy to analyze the residue obtained by evaporating the water present around the orifice. The residue contained organic matter, including carotenoids, amides, esters, and sugars, which were similar to those found in the membranes generated in the orifice in our previous paper, suggesting that the organic matter was synthesized in a wide region of water around the orifice as well as in the orifice. These results may be relevant to the origins of life and biology, and may lead to the development of a technology for reducing CO2 in air, as well as applications in many scientific and engineering fields.

Disorder-induced quantum bond percolation.

We investigate the effects of off-diagonal disorder on localization properties in quantum bond percolation networks on cubic lattices, motivated by the finding that the off-diagonal disorder does not always enhance the quantum localization of wavefunctions. We numerically construct a diagram of the 'percolation threshold', distinguishing extended states from localized states as a function of two degrees of disorder, by using the level statistics and finite-size scaling. The percolation threshold increases in a characteristic way on increasing the disorder in the connected bonds, while it gradually decreases on increasing the disorder in the disconnected bonds. Furthermore, the exchange of connected and disconnected bonds induced by the disorder causes a dramatic change of the percolation threshold.

Organic compounds generated after the flow of water through micro-orifices: Were they synthesized?

Micro-fluid mechanics is an important area of research in modern fluid mechanics because of its many potential industrial and biological applications. However, the field is not fully understood yet. In previous work, when passing ultrapure water (UPW) in which air was dissolved (UPW*) through micro-orifices, we found that the flow velocity decreased and stopped over time, and membranes were frequently formed in the orifice when the flow stopped. The membrane came from the dissolved air in UPW*, and membrane formation was closely related to electric charges generated in orifices by the flow. In the present paper, we clarified the components of the membrane and suggested a mechanism for membrane formation. We examined the effect of contaminants on the membrane formation and confirmed our previous results. We identified the chemical components of the membrane and those present in the UPW* itself by using an electron probe microanalyzer and found that the proportion of each element differed between the membrane and UPW*. Raman and infrared (IR) spectroscopy showed that the membrane consisted of organic substances such as carotenoids, amides, esters, and sugars. We irradiated UPW* with ultraviolet light to cut organic chains that may be left in UPW* as contaminants. We found a similar membrane and organic compounds as in nonirradiated UPW*. Furthermore, although the UPW that was kept from contact with air after it was supplied from the UPW maker (UPW0) and bubbled with Ar gas (UPW0 bubbled with Ar) formed no membrane, the UPW0 bubbled with CO2 formed thin membranes, and Raman and IR analysis showed that this membrane contained carboxylic acid salts, carotenoids, or a mixture of both. We found that electric grounding of the orifice reduces the probability of membrane formation and that the jets issuing from an aperture bear negative charges, and we assumed that the micro-orifices possess positive charges generated by flows. Consequently, we suggest that organic compounds are synthesized from nonorganic matter in air or CO2 dissolved in water by the action of hydroxyl radicals generated by flows through micro-orifices.

Origin of most primitive mRNAs and genetic codes via interactions between primitive tRNA ribozymes.

The origin and early evolution of genetic codon system and early mRNAs were analyzed from a viewpoint of primordial gene theory and the poly-tRNA theory. A hypothetical 25-amino acid (aa)-primordial peptide was deduced from internal aa-sequence homology of adenylate kinases. Theoretical models were made which can reasonably explain how primitive tRNA(s) could have had converted to be earliest mRNAs via interactions between presumptive anticodons and (poly-)tRNA ribozyme. Transfer-RNA gene clusters in the trrnD- and rrnB-operons of Bacillus subtilis seemed to be relics of early peptide-synthesizing RNA machine. Detailed analyses revealed that the poly-tRNA regions in these operons are true relics of RNA-machine for making a 16-aa trrnD-peptide and a 21-aa rrnB-peptide, whose aa sequences are in the order of aa specificities of tRNAs in the tRNA gene clusters of the trrnD-operon and rrnB-operon, respectively. The primordial gene-encoded peptide deduced from adenylate kinases were found to be a genuine homologue of the rrnB-peptide. Various protein superfamilies were found to have evolved from either of these two types of primitive peptides. Earliest mRNAs were concluded to have evolved from tRNAGly (trrnD-mRNA) or tRNAHis (rrnB-mRNA), where trrnD- and rrnB-mRNAs are hypothetical primitive mRNAs complementary to the tandem arrangement of 16 or 21 anticodons of tRNAs in the trrnD-operon and rrnB-operon, respectively. The poly-tRNA model is considered to be an excellent theory, because it can reasonably explain origins of both genetic codes and earliest mRNAs, and because the hypothesis can be statistically evaluated by base-identity levels in proper alignments. The genetic codon system is a typical mature semeiotic system within a cell, and the genesis of the genetic codon system was discussed from an aspect of de Saussure's semeiology. Arbitrary correspondence between (anti)codon and aa would be most plausibly a result of semeiotic culture system of intracellular tRNA-riboorganismic society.

Inverse Anderson transition caused by flatbands.

We propose a new disorder-induced insulator-metal transition of one-electron states, which may be called the "inverse Anderson transition." We first make a highly degenerated localized states by constructing a three-dimensional periodic system possessing only flat dispersion relations. When we introduce a disorder into it, a finite-size scaling of the level statistics shows two clear (localization-delocalization and delocalization-localization) transitions for a wide range of the energy, with increasing the degree of disorder. These transitions are confirmed also by finding the system-size-independent characteristic of the wave function.