Insight into chemical mechanisms of sepal color development and variation in hydrangea

Hydrangea (Hydrangea macrophylla) is a unique flower because it is composed of sepals rather than true petals that have the ability to change color. In the early 20th century, it was known that soil acidity and Al³⁺ content could intensify the blue hue of the sepals. In the mid-20th century, the anthocyanin component 3-O-glucosyldelphinidin (1) and the copigment components 5-O-caffeoylquinic, 5-O-p-coumaroylquinic, and 3-O-caffeoylquinic acids (2–4) were reported. Interestingly, all hydrangea colors from red to purple to blue are produced by the same organic components. We were interested in this phenomenon and the chemical mechanisms underlying hydrangea color variation. In this review, we summarize our recent studies on the chemical mechanisms underlying hydrangea sepal color development, including the structure of the blue complex, transporters involved in accumulation of aluminum ion (Al³⁺), and distribution of the blue complex and aluminum ions in living sepal tissue.     

Super strong nuclear force caused by migrating K? mesons - Revival of the Heitler-London-Heisenberg scheme in kaonic nuclear clusters

We have studied the structure of K⁻pp comprehensively by solving this threebody system in a variational method, starting from the Ansatz that the Λ(1405) resonance (≡Λ^*) is a K⁻p bound state. The structure of K⁻pp reveals a molecular feature, namely, the K⁻ in Λ^* as an “atomic center” plays a key role in producing strong covalent bonding with the other proton. We point out that strongly bound $\bar{K}$ nuclear systems are formed by “super strong” nuclear force due to migrating real bosonic particles $\bar{K}$ a la Heitler-London-Heisenberg, whereas the normal nuclear force is caused by mediating virtual mesons. We have shown that the elementary process, p + p → K⁺ + Λ^* + p, which occurs in a short impact parameter and with a large momentum transfer, leads to unusually large self-trapping of Λ^* by the involved proton, since the Λ^*-p system exists as a compact doorway state propagating to K⁻pp.     

New developments of polysaccharide synthesis via enzymatic polymerization

This review focuses on the in vitro synthesis of polysaccharides, the method of which is “enzymatic polymerization” mainly developed by our group. Polysaccharides are formed by repeated glycosylation reactions between a glycosyl donor and a glycosyl acceptor. A hydrolysis enzyme was found very efficient as catalyst, where the monomer is designed based on the new concept of a “transition-state analogue substrate” (TSAS); sugar fluoride monomers for polycondensation and sugar oxazoline monomers for ring-opening polyaddition. Enzymatic polymerization enabled the first in vitro synthesis of natural polysaccharides such as cellulose, xylan, chitin, hyaluronan and chondroitin, and also of unnatural polysaccharides such as a cellulose–chitin hybrid, a hyaluronan–chondroitin hybrid, and others. Supercatalysis of hyaluronidase was disclosed as unusual enzymatic multi-catalyst functions. Mutant enzymes were very useful for synthetic and mechanistic studies. In situ observations of enzymatic polymerization by SEM, TEM, and combined SAS methods revealed mechanisms of the polymerization and of the self-assembling of high-order molecular structure formed by elongating polysaccharide molecules.     

Electroluminescent properties of dimeric bis(2-(2′-hydroxyl phenyl)benzthiazolate)zinc (II) complex

A blue shifted photoluminescent emission in bis(2-(2′-hydroxyl phenyl)benzthiazolate)zinc (II) complex, ZBZT, arises out of the dimeric structure, typical of the localized electron density around the non-bridged ligand in the excited state of the complex. An average decay lifetime of 4.8 and 3.0 ns for the ligand and the complex, respectively indicates an energy transfer from the ligand to the metal. A PL quantum efficiency of about ?_ZBZT=0.45 in DMF solution is observed, in comparison to the Alq₃, complex, ?_Alq3=0.116. Semi empirical ZINDO/S-SCF-CI calculations support the dominance of non-bridged ligand moiety in controlling the photoluminescent properties. An unusually broad white light (FWHM ∼220 nm) electroluminescent emission in the two layer device structure brings out the features of an exciplex formation between the active layer ZBZT/TPD interface, which is studied at different current densities. Such a broadened emission is verified for different thicknesses of the active layer substantiating the role of exciplex formation.     

Coupled Criticality Analysis of Inflation and Unemployment

In this paper, we focus on the critical periods in the economy that are characterized by unusual and large fluctuations in macroeconomic indicators, like those measuring inflation and unemployment. We analyze U.S. data for 70 years from 1948 until 2018. To capture their fluctuation essence, we concentrate on the non-Gaussianity of their distributions. We investigate how the non-Gaussianity of these variables affects the coupling structure of them. We distinguish “regular” from “rare” events, in calculating the correlation coefficient, emphasizing that both cases might lead to a different response of the economy. Through the “multifractal random wall” model, one can see that the non-Gaussianity depends on time scales. The non-Gaussianity of unemployment is noticeable only for periods shorter than one year; for longer periods, the fluctuation distribution tends to a Gaussian behavior. In contrast, the non-Gaussianities of inflation fluctuations persist for all time scales. We observe through the “bivariate multifractal random walk” that despite the inflation features, the non-Gaussianity of the coupled structure is finite for scales less than one year, drops for periods larger than one year, and becomes small for scales greater than two years. This means that the footprint of the monetary policies intentionally influencing the inflation and unemployment couple is observed only for time horizons smaller than two years. Finally, to improve some understanding of the effect of rare events, we calculate high moments of the variables’ increments for various q orders and various time scales. The results show that coupling with high moments sharply increases during crises.     

Inaccurate mate recognition as a mating strategy of a ‘pioneer male’

Heterosubspecific mating experiments were carried out between two subspecies of cabbage butterflies, British Pieris rapae rapae and Japanese P. rapae crucivora, to examine how accurately males recognize the mates. The two subspecies are different in that the wings of female P. rapae rapae reflect little UV light, whereas those of female P. rapae crucivora are strongly UV-reflective. The wing colouration of P. rapae crucivora involving UV is believed to be critical in mate recognition. The results showed that males of both subspecies displayed mating behaviours, to and copulated with, females of both subspecies. Furthermore, P. rapae crucivora males exhibited mating behaviours and attempted to copulate with females of Pieris melete with low UV reflectance which are critically different from P. rapae crucivora females with high UV reflectance. Based on these findings, we propose the “pioneer male” hypothesis, which argues that such inaccurate mate recognition may sometimes be selectively beneficial for males and thus an adaptive mating strategy. The “pioneer male” was discussed in terms of its possible role in the evolution.     

Micro‐Raman and portable Raman spectroscopic investigation of blue pigments in selected Delft plates (17–20th Century)

The blue pigment as well as other materials in a blue, white and ‘gold’ 17th century Delft dish were analysed and compared to the blue pigment(s) used in a modern blue‐and‐white Delft dish, obtained from a tourist shop in Amsterdam in 2004. The ancient Delft blue pigment was compared to a commercial Delft blue powder identified as a cobalt‐doped willemite, Zn_2−xCo_xSiO₄. The 17th century Delft pigment showed a closer correspondence to the olivine, alpha‐cobalt silicate. The pigment in the modern blue Delft dish was mainly a vanadium‐doped zircon, ZrSiO₄:V⁴⁺, with small amounts of cobalt, identified by EDX analysis. The cobalt compound could, however, not be characterised here for the modern dish. The pigment in the ‘golden’ rim was identified as pyrochlore yellow, PbSnSbO_6.5. Copyright © 2009 John Wiley & Sons, Ltd.     

Strong binding and shrinkage of single and double nuclear systems (K?pp,K?ppn,K?K?p and K?K?pp) predicted by Faddeev-Yakubovsky calculations

Non-relativistic Faddeev and Faddeev-Yakubovsky calculations were made for K⁻pp, K⁻ppn, K⁻K⁻p and K⁻K⁻pp kaonic nuclear clusters, where the quasi bound states were treated as bound states by employing real separable potential models for the K⁻-K⁻ and the K⁻-nucleon interactions as well as for the nucleon-nucleon interaction. The binding energies and spatial shrinkages of these states, obtained for various values of the interaction, were found to increase rapidly with the interaction strength. Their behaviors are shown in a reference diagram, where possible changes by varying the interaction in the dense nuclear medium are given. Using the Λ(1405) ansatz with a PDG mass of 1405 MeV/c² for K⁻p, the following ground-state binding energies together with the wave functions were obtained: 51.5 MeV (K⁻pp), 69 MeV (K⁻ppn), 30.4 MeV (K⁻K⁻p) and 93 MeV (K⁻K⁻pp), which are in good agreement with previous results of variational calculation based on the Akaishi-Yamazaki coupled-channel potential. The K⁻K⁻pp state has a significantly increased density where the two nucleons are located very close to each other, in spite of the inner NN repulsion. Relativistic corrections on the calculated non-relativistic results indicate substantial lowering of the bound-state masses, especially of K⁻K⁻pp, toward the kaon condensation regime. The fact that the recently observed binding energy of K⁻pp is much larger (by a factor of 2) than the originally predicted one may infer an enhancement of the interaction in dense nuclei by about 25% possibly due to chiral symmetry restoration. In this respect some qualitative accounts are given based on “clearing QCD vacuum” model of Brown, Kubodera and Rho.     

Direct experimental evidence of the hyperfine predissociation of molecular iodine using a saturated absorption experiment

A saturated absorption technique using an actively stabilized C.W. dye laser has been used to study the hyperfine structure of some lines lying in the 9-3, 10-3, 11-3, 11-4, 12-3 bands of the B-X system of molecular iodine. The comparison of the different spectra shows that the intensities of the different hyperfine components of one line deviate from the 2F + 1 proportionality when 'v decreases towards the value 'v=6 where the potential curves of the ³Π⁺₀ and 1u states are crossing. The preliminary experimental results concerning the hyperfine component intensity variations versus the quantum numbers 'v, J and F give a direct qualitative support to the recently reported hyperfine predissociation in I₂.     

No Preferred Reference Frame at the Foundation of Quantum Mechanics

Quantum information theorists have created axiomatic reconstructions of quantum mechanics (QM) that are very successful at identifying precisely what distinguishes quantum probability theory from classical and more general probability theories in terms of information-theoretic principles. Herein, we show how one such principle, Information Invariance and Continuity, at the foundation of those axiomatic reconstructions, maps to “no preferred reference frame” (NPRF, aka “the relativity principle”) as it pertains to the invariant measurement of Planck’s constant h for Stern-Gerlach (SG) spin measurements. This is in exact analogy to the relativity principle as it pertains to the invariant measurement of the speed of light c at the foundation of special relativity (SR). Essentially, quantum information theorists have extended Einstein’s use of NPRF from the boost invariance of measurements of c to include the SO(3) invariance of measurements of h between different reference frames of mutually complementary spin measurements via the principle of Information Invariance and Continuity. Consequently, the “mystery” of the Bell states is understood to result from conservation per Information Invariance and Continuity between different reference frames of mutually complementary qubit measurements, and this maps to conservation per NPRF in spacetime. If one falsely conflates the relativity principle with the classical theory of SR, then it may seem impossible that the relativity principle resides at the foundation of non-relativisitic QM. In fact, there is nothing inherently classical or quantum about NPRF. Thus, the axiomatic reconstructions of QM have succeeded in producing a principle account of QM that reveals as much about Nature as the postulates of SR.     

Vitamin D and bone: — How does vitamin D regulate bone formation and resorption? —

Vitamin D was discovered as an anti-rachitic agent, but even at present, there is no direct evidence to support the concept that vitamin D directly stimulates osteoblastic bone formation and mineralization. It appears to be paradoxical, but vitamin D functions in the process of osteoclastic bone resorption. Osteoclasts, the only cells responsible for bone resorption, develop from hematopoietic cells of the monocyte-macrophage lineage. In 1992, we hypothesized that a membrane-bound factor, designated as “osteoclast differentiation factor (ODF)”, is expressed on the plasma membrane of osteoblasts/stromal cells in response to osteotropic factors including the active form of vitamin D₃, 1α,25-dihydroxyvitamin D₃ [1α,25(OH)₂D₃]. Recently, four research groups including ours independently identified three key molecules (RANKL, RANK, and OPG) responsible for osteoclastogenesis. A long-sought-after ligand, ODF, was identical to RANKL. RANKL was a member of the membrane-associated TNF ligand family, which induced differentiation of spleen cells (osteoclast progenitors) into osteoclasts in the presence of M-CSF. RANK, a member of the TNF receptor family, was a signaling receptor essential for the RANKL-mediated osteoclastogenesis. OPG, a secreted member of the TNF receptor family, was a decoy receptor for RANKL. The discovery of RANKL, RANK and OPG opens a new era in the study of bone biology and the therapy of several metabolic bone diseases such as osteoporosis, rheumatoid arthritis, and periodontal diseases.     

Thermodynamic Properties of the First-Generation Hybrid Dendrimer with “Carbosilane Core/Phenylene Shell” Structure

The molar heat capacity of the first-generation hybrid dendrimer with a “carbosilane core/phenylene shell” structure was measured for the first time in the temperature range T = 6–600 K using a precise adiabatic vacuum calorimeter and DSC. In the above temperature interval, the glass transition of the studied compound was observed, and its thermodynamic characteristics were determined. The standard thermodynamic functions (the enthalpy, the entropy, and the Gibbs energy) of the hybrid dendrimer were calculated over the range from T = 0 to 600 K using the experimentally determined heat capacity. The standard entropy of formation of the investigated dendrimer was evaluated at T = 298.15 K. The obtained thermodynamic properties of the studied hybrid dendrimer were compared and discussed with the literature data for some of the first-generation organosilicon and pyridylphenylene dendrimers.     

Implementation of Fault-Tolerant Encoding Circuit Based on Stabilizer Implementation and “Flag” Bits in Steane Code

Quantum error correction (QEC) is an effective way to overcome quantum noise and de-coherence, meanwhile the fault tolerance of the encoding circuit, syndrome measurement circuit, and logical gate realization circuit must be ensured so as to achieve reliable quantum computing. Steane code is one of the most famous codes, proposed in 1996, however, the classical encoding circuit based on stabilizer implementation is not fault-tolerant. In this paper, we propose a method to design a fault-tolerant encoding circuit for Calderbank-Shor-Steane (CSS) code based on stabilizer implementation and “flag” bits. We use the Steane code as an example to depict in detail the fault-tolerant encoding circuit design process including the logical operation implementation, the stabilizer implementation, and the “flag” qubits design. The simulation results show that assuming only one quantum gate will be wrong with a certain probability p, the classical encoding circuit will have logic errors proportional to p; our proposed circuit is fault-tolerant as with the help of the “flag” bits, all types of errors in the encoding process can be accurately and uniquely determined, the errors can be fixed. If all the gates will be wrong with a certain probability p, which is the actual situation, the proposed encoding circuit will also be wrong with a certain probability, but its error rate has been reduced greatly from p to p2 compared with the original circuit. This encoding circuit design process can be extended to other CSS codes to improve the correctness of the encoding circuit.     

Condensation and Crystal Nucleation in a Lattice Gas with a Realistic Phase Diagram

We reconsider model II of Orban et al. (J. Chem. Phys. 1968, 49, 1778–1783), a two-dimensional lattice-gas system featuring a crystalline phase and two distinct fluid phases (liquid and vapor). In this system, a particle prevents other particles from occupying sites up to third neighbors on the square lattice, while attracting (with decreasing strength) particles sitting at fourth- or fifth-neighbor sites. To make the model more realistic, we assume a finite repulsion at third-neighbor distance, with the result that a second crystalline phase appears at higher pressures. However, the similarity with real-world substances is only partial: Upon closer inspection, the alleged liquid–vapor transition turns out to be a continuous (albeit sharp) crossover, even near the putative triple point. Closer to the standard picture is instead the freezing transition, as we show by computing the free-energy barrier relative to crystal nucleation from the “liquid”.     

Does Decoherence Select the Pointer Basis of a Quantum Meter?

The consensus regarding quantum measurements rests on two statements: (i) von Neumann’s standard quantum measurement theory leaves undetermined the basis in which observables are measured, and (ii) the environmental decoherence of the measuring device (the “meter”) unambiguously determines the measuring (“pointer”) basis. The latter statement means that the environment monitors (measures) selected observables of the meter and (indirectly) of the system. Equivalently, a measured quantum state must end up in one of the “pointer states” that persist in the presence of the environment. We find that, unless we restrict ourselves to projective measurements, decoherence does not necessarily determine the pointer basis of the meter. Namely, generalized measurements commonly allow the observer to choose from a multitude of alternative pointer bases that provide the same information on the observables, regardless of decoherence. By contrast, the measured observable does not depend on the pointer basis, whether in the presence or in the absence of decoherence. These results grant further support to our notion of Quantum Lamarckism, whereby the observer’s choices play an indispensable role in quantum mechanics.     

The CuPL defect and the Cus1Cui3 complex

The Cu_PL defect is characterized by intense photoluminescence (PL) emission with a 1014 meV zero-phonon line and has since long been called the ‘copper-pair’ defect. However, recent PL studies in isotopically pure ²⁸Si samples show clear evidence for four Cu atoms in this defect. This defect is one of a family of complexes that contain four (sometimes five) metal impurities. No complex containing two or three metal impurities (at least one of which is a transition metal) has been reported. We have performed systematic calculations of a priori possible Cu₄ complexes, including the Cu_s1Cu_i3 complex proposed by Shirai et al. [18]. This complex has the lowest formation energy of all the Cu₄ defects. We have studied its properties using first-principle theory. In addition to the structures, binding energies, and vibrational spectra, we studied the formation pathway in an attempt to figure out why smaller (or larger) complexes do not form. We find that Cu_s1Cu_in with n=0, 1 or 2 continue to trap Cu_i⁺ if the Fermi level is midgap, and that the process stops when n=3. © 2011 Elsevier Science. All rights reserved     

Synthesis and fading of eighteenth‐century Prussian blue pigments: a combined study by spectroscopic and diffractive techniques using laboratory and synchrotron radiation sources

Prussian blue, a hydrated iron(III) hexacyanoferrate(II) complex, is a synthetic pigment discovered in Berlin in 1704. Because of both its highly intense color and its low cost, Prussian blue was widely used as a pigment in paintings until the 1970s. The early preparative methods were rapidly recognized as a contributory factor in the fading of the pigment, a fading already known by the mid‐eighteenth century. Herein two typical eighteenth‐century empirical recipes have been reproduced and the resulting pigment analyzed to better understand the reasons for this fading. X‐ray absorption and Mössbauer spectroscopy indicated that the early syntheses lead to Prussian blue together with variable amounts of an undesirable iron(III) product. Pair distribution functional analysis confirmed the presence of nanocrystalline ferrihydrite, Fe₁₀O₁₄(OH)₂, and also identified the presence of alumina hydrate, Al₁₀O₁₄(OH)₂, with a particle size of ～15 Å. Paint layers prepared from these pigments subjected to accelerated light exposure showed a tendency to turn green, a tendency that was often reported in eighteenth‐ and nineteenth‐century books. The presence of particles of hydrous iron(III) oxides was also observed in a genuine eighteenth‐century Prussian blue sample obtained from a polychrome sculpture.     

Doppler-free two-photon excitation of nitric oxide with frequency-stabilized cw dye laser radiation

Doppler-free two-photon transitions are induced in nitric oxide with blue, narrowband, tunable radiation generated by a frequency-stabilized cw dye ring laser. The recorded two-photon spectra provide a precise measurement of the spin-rotation splitting of the excited rotational levels (A ²∑⁺, ν' = 0) N' = 1 to N' = 19. The splitting constant γ is determined to be γ = 80.35(15) MHz.     

Phase transition in spin systems with various types of fluctuations

Various types ordering processes in systems with large fluctuation are overviewed. Generally, the so-called order–disorder phase transition takes place in competition between the interaction causing the system be ordered and the entropy causing a random disturbance. Nature of the phase transition strongly depends on the type of fluctuation which is determined by the structure of the order parameter of the system. As to the critical property of phase transitions, the concept “universality of the critical phenomena” is well established. However, we still find variety of features of ordering processes. In this article, we study effects of various mechanisms which bring large fluctuation in the system, e.g., continuous symmetry of the spin in low dimensions, contradictions among interactions (frustration), randomness of the lattice, quantum fluctuations, and a long range interaction in off-lattice systems.