Elasticity of nanocrystalline kyanite at high pressure and temperature from ultrasonic and synchrotron X-ray techniques

Material properties, such as elasticity data at wide-ranging conditions of pressure and temperature, attract increasing attention for material and earth sciences. In particular, polycrystalline ceramics for next-generation photonic applications are nowadays fabricated by advanced syntheses techniques operating under elevated pressures and temperatures. Herein, the elastic properties of a synthetic transparent and reinforced aluminosilicate nanoceramic composed of triclinic kyanite with minor amounts of trigonal α-alumina crystals are investigated using in situ synchrotron X-ray diffraction and ultrasonic techniques at high-pressure (up to 11 GPa) and high-temperature (300-1500 K) conditions. This not only enables the determination of the equation of state (EoS) parameters by applying the pressure-volume-temperature (P-V-T) data to the high-temperature Birch-Murnaghan EoS but also yields the elastic moduli together with their P and T derivatives from the fit of the compressional and shear wave velocities to a finite strain EoS: K_S0,300 = 186(2) GPa, K′_S0,300 = 7.2(6), (∂K_S0,300/∂T)_P = −0.023(2) GPa K⁻¹, G_0,300 = 125(1) GPa G′_0,300 = 2.3(2), (∂G_0,300/∂T)_P = −0.017(1) GPa K⁻¹. On the basis of our acquired results, we propose to predict the elastic moduli of aluminosilicate ceramics by a linear function of the ratio of AlO₆ octahedra and SiO₄ tetrahedra within the constituting phases.     

α‐Complementation in an Artificial Genome Replication System in Liposomes

Genome size is considered one of the limiting factors for the replication of primitive life forms. However, the relationship between genome size and replication efficiency has not been tested experimentally. In this study, we examined the effect of genome size on genome replication by using an artificial cell model: a self‐replicating RNA genome encapsulated in a liposome. For the reduced genome size we used α‐complementation of the lacZ gene. We first characterized α‐complementation in the purified translation system and then applied α‐complementation to the genome replication system. The reduction in the genome size together with the addition of ω‐fragment increased the replication efficiency approximately eightfold. This result provides experimental evidence that genome size can be a limiting factor for primitive self‐replication systems; it also implies that this artificial cell model could be a useful experimental model to identify possible mechanisms of genome enlargement.     

Design and implementation of a user-support system for scheduling using a smart phone

In recent years, the ability to manage schedules using a mobile device equipped with a touch panel has increased. However, when one wishes to add a new event to the schedule book while taking into account the transit time for an existing event, it is necessary to switch to another application or website. In this study, we design a system that determines automatically whether the new event can be added. If it is impossible to add the event, the system proposes a time range in which events can be added.     

Seedless growth of zinc oxide flower-shaped structures on multilayer graphene by electrochemical deposition

A seedless growth of zinc oxide (ZnO) structures on multilayer (ML) graphene by electrochemical deposition without any pre-deposited ZnO seed layer or metal catalyst was studied. A high density of a mixture of vertically aligned/non-aligned ZnO rods and flower-shaped structures was obtained. ML graphene seems to generate the formation of flower-shaped structures due to the stacking boundaries. The nucleation of ZnO seems to be promoted at the stacking edges of ML graphene with the increase of applied current density, resulting in the formation of flower-shaped structures. The diameters of the rods/flower-shaped structures also increase with the applied current density. ZnO rods/flower-shaped structures with high aspect ratio over 5.0 and good crystallinity were obtained at the applied current densities of −0.5 and −1.0 mA/cm². The growth mechanism was proposed. The growth involves the formation of ZnO nucleation below 80°C and the enhancement of the growth of vertically non-aligned rods and flower-shaped structures at 80°C. Such ZnO/graphene hybrid structure provides several potential applications in sensing devices.     

Zeolite synthesis from paper sludge ash at low temperature (90 degrees C) with addition of diatomite

Paper sludge ash was partially converted into zeolites by reaction with 3M NaOH solution at 90 degrees C for 24 h. The paper sludge ash had a low abundance of Si and significant Ca content, due to the presence of calcite that was used as a paper filler. Diatomite was added to the NaOH solution to increase its Si content in order to synthesize zeolites with high cation exchange capacity. Diatomite residue was filtered from solution before addition of ash. The original ash without addition of diatomite yielded hydroxysodalite with a cation exchange capacity ca. 50 cmol/kg. Addition of Si to the solution yielded Na-P1 (zeolite-P) with a higher cation exchange capacity (ca. 130 cmol/kg). The observed concentrations of Si and Al in the solution during the reaction explain the crystallization of these two phases. The reaction products were tested for their capacity for PO(4)(3-) removal from solution as a function of Ca(2+) content, suggesting the formation of an insoluble Ca-phosphate salt. The product with Na-P1 exhibits the ability to remove NH(4)(+) as well as PO(4)(3-) from solution in concentrations sufficient for application in water purification. Both NH(4)(+) and PO(4)(3-) removal showed little variation with pH between 5 and 9. Alternative processing methods of zeolite synthesis, including the addition of ash to an unfiltered Si-NaOH solution and addition of a dry ash/diatomite mixture to NaOH solution, were tested. The third process yielded materials with lower cation exchange capacity due to formation of hydroxysodalite. The second process results in a product with relatively high cation exchange capacity, and reduces the number of processing steps necessary for zeolite synthesis.     

Effect of Fe and partial pressure of oxygen on the formation and phase transformation behavior of Al2O3 scale

The effect of oxygen partial pressure on the phase transformation of Al₂O₃ scale on various Fe–Al alloys with and without very thin (～100 nm) Fe coating was investigated. Fe‐coating on Fe–Al alloys can effectively suppress metastable Al₂O₃ formation, but little effect was observed when the samples were oxidized in a low partial pressure of oxygen. Under the low ${\rm P}_{{\rm O}_{{\rm 2}} } $ atmosphere, metastable to stable α‐Al₂O₃ scale phase transformation on both Fe‐coated and non‐coated Fe–Al alloys was significantly delayed. The lattice spacing of α‐Al₂O₃ scale formed in air decreased with increasing alloy Al content. Further decrease in the lattice spacing of α‐Al₂O₃ scale was observed when the alloy was oxidized in low ${\rm P}_{{\rm O}_{{\rm 2}} } $ . The results obtained clearly indicated that the formation of Fe₂O₃ or Fe³⁺ in metastable Al₂O₃ accelerated the metastable to stable α‐Al₂O₃ scale transformation.     

A PEG-based biocompatible block catiomer with high buffering capacity for the construction of polyplex micelles showing efficient gene transfer toward primary cells

Nonviral gene vectors from synthetic catiomers (polyplexes) are a promising alternative to viral vectors. In particular, many recent efforts have been devoted to the construction of biocompatible polyplexes for in vivo nonviral gene therapy. A promising approach in this regard is the use of poly(ethylene glycol) (PEG)-based block catiomers, which form a nanoscaled core-shell polyplex with biocompatible PEG palisades. In this study, a series of PEG-based block catiomers with different amine functionalities were newly prepared by a simple and affordable synthetic procedure based on an aminolysis reaction, and their utility as gene carriers was investigated. This study revealed that the block catiomers carrying the ethylenediamine unit at the side chain are capable of efficient and less toxic transfection even toward primary cells, highlighting critical structural factors of the cationic units in the construction of polyplex-type gene vectors. Moreover, the availability of the polyplex micelle for transfection with primary osteoblasts will facilitate its use for bone regeneration in vivo mediated by nonviral gene transfection.     

Pedunculated hepatic hemangioma identified on Tc-99m DTPA-HSA scintigraphy

Traumatic transection of the base of the tongue can be a life-threatening injury because of blood loss and airway obstruction. Airway control, hemostasis, and meticulous anatomic repair are necessary to prevent speech and airway dysfunction. Laryngeal injuries, when present, require these same principles.     

A simultaneous testing of the mean vector and the covariance matrix among two populations for high-dimensional data

In this article, we propose an \(L^2\)-norm-based test for simultaneous testing of the mean vector and the covariance matrix under high-dimensional non-normal populations. To construct this, we derive an asymptotic distribution of a test statistic based on both differences mean vectors and covariance matrices. We also investigate the asymptotic sizes and powers of the proposed test using this result. Finally, we study the finite sample and dimension performance of this test via Monte Carlo simulations.