Effect of Na, K and Fe on the formation of α- and β-Ca2SiO4

The contribution of Fe to C₂S polymorphs is effectively revealed for β-C₂S formation and is not for α′- or α-C₂S. However in co-existing of Na or K with Fe, the α-C₂S is easily stabilized, though accompanied with small amount of crystalline Ca₂Fe₂O₅ as the interstitial material. This effect of Fe on α- and β-C₂S synthesis was investigated by XRD, chemical analysis and Mössbauer spectra observation. Comparing calculated Mössbauer parameters of α- and β-C₂S with those of other minerals, it was confirmed that they included only Fe³⁺ at octahedral and tetrahedral sites with the ratio 30:70 in Na---Fe substituted α-form and with 63:37 in K---Fe substituted α-form. In β-C₂S, Fe³⁺ was mostly situated at tetrahedral site. The formulas of α- and β-C₂S were decided and shown as, (Ca_1.88Fe_0.05Na_0.24)(Si_0.88Fe_0.11)O₄, (Ca_1.94 Fe_0.09K_0.18) (Si_0.88Fe_0.05)O₄ for α-form and (Ca_1.93Fe_0.003Na_0.04) (Si_0.99Fe_0.05)O₄, (Ca_1.94Fe_0.01K_0.04) (Si_0.92Fe_0.13)O₄ for -form.     

Reliabilities and concurrent validities of popular self-report measures of depression, anxiety, and social desirability.

135 male and 256 female undergraduates completed the Self-Rating Depression Scale, Beck Depression Inventory, Depression Adjective Check Lists, State-Trait Anxiety Inventory, Taylor Manifest Anxiety Scale, S-R Inventory of Anxiousness, Marlowe-Crowne Social Desirability Scale, and Edwards Social Desirability Scale. Pearson correlation coefficients indicated strong relationships between measures of depression and between measures of anxiety. However, pairs of anxiety and depression measures correlated almost as strongly. All depression and anxiety measures were significantly associated with the Edwards Social Desirability Scale. Findings question the use of a self-report measure of depression to select "depressed" Ss among college students. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

One-Dimensional Phonon State of 4He Films Adsorbed in Straight Nanopores

We have studied heat capacities of ⁴He adsorbed in straight nanopores 1.8, 2.2, and 2.8 nm in diameter. Heat capacities of the ⁴He fluid film on the solid layer at 0.08–0.4 K show power laws close to T in 1.8 nm pores, close to T ² in 2.8 nm pores, and a crossover from T to T ² with increasing temperature in 2.2 nm pores. These heat capacities are explained by a model assuming a phonon dispersion with continuous one-dimensional (1D) states in the axial direction and discrete energy levels in the azimuthal direction. By fitting experimental data to the model, the phonon velocity along the pore axis and the energy gap for propagation in the cross section are derived. At temperatures sufficiently lower than the energy gap, where the thermal wave length of phonons is much longer than the effective pore diameter, the ⁴He fluid films show a T-linear heat capacity of 1D phonons propagating only along the pore axis. At higher temperatures, a 1D-2D crossover of phonons occurs.      

Indoor and outdoor concentrations of Japanese cedar pollens and total suspended particulates: A case study at a kindergarten in Japan

Japanese cedar pollinosis (JCP) caused by allergenic cedar and cypress pollens is one of major economic and health issues in Japan. The present study reported here aimed to provide basic data to understand the status of early life exposures to airborne cedar and cypress pollens in school settings. In particular, the study investigated relationships between indoor and outdoor concentrations of airborne cedar and cypress pollens and total suspended particulates (TSP) in a kindergarten in Japan. Overall, outdoor concentrations of the airborne pollens and TSP were higher than the indoor concentrations, i.e., indoor to outdoor (I/O) ratios of 0.043–0.055 and 0.545 for the airborne pollens and TSP, respectively. The smaller I/O ratios for the pollens were expected because the larger pollen grains (20–30 μm in diameter) were less likely penetrated to indoor environment than for smaller airborne particulates. The present study also found increased TSP concentrations during the pollen season was likely attributed to increased airborne pollen concentrations. By understanding the status of indoor and outdoor concentrations of airborne cedar and cypress pollens in school settings, early life exposures to these allergenic pollens should be effectively minimized to prevent subsequent progression to JCP symptoms.     

Preparation and evaluation of a novel wound dressing sheet comprised of β-glucan–chitosan complex

A transparent wound dressing sheet was obtained by forming a complex between β-glucan and chitosan (CS). These materials were chosen for their biocompatible, bioabsorbable, and biodegradable properties, and they were expected to promote the therapeutic efficacy of the dressing by increasing the wound healing response. The therapeutic efficacy of the β-glucan–CS complex sheet as a wound dressing was evaluated in wounds created on the dorsal surfaces of mice. β-glucan–CS complex sheets demonstrated therapeutic efficacies comparable or superior to that of Beschitin®W, a commercial wound dressing made from CS. Additionally, the β-glucan–CS complex sheet did not dissolve during the application period, did not adhere to wounds, and was easy to remove. Cumulatively, these results indicate that β-glucan–CS complex sheets are a promising new wound dressing product.     

Relative reactivity of phenylboronic acid to phenylboronate ion toward L-lactate and mandelate at physiological pH

Kinetic studies were performed on the reactions of phenylboronic acid with L-lactic acid and mandelic acid in acidic aqueous and alkaline solutions in order to specify reactive species in these reactions. It was confirmed that the diprotonated ligand (H₂L: L-lactic acid or mandelic acid) is less reactive than the monoprotonated ligand (HL^?: L-lactate ion or mandelate ion), which made possible direct determination of the rate constants of phenylboronic acid (PhB(OH)₂) and its conjugate base, phenylboronate ion (PhB(OH)₃^?). It was found that PhB(OH)₂ is more reactive than PhB(OH)₃^?. On the basis of kinetic results, it was concluded that the most reactive species are PhB(OH)₂ and HL^? at physiological pH 7.4, so the reaction in the boronic acid-based sensor for L-lactate mainly would occur between these species.     

Formate dehydrogenase gene of Arabidopsis thaliana is induced by formaldehyde and not by formic acid

Variability of expression of formate dehydrogenase (FDH) caused by uptake of C-1 compounds was examined by using Arabidopsis thaliana as a model plant. Effects of uptake of several C-1 compounds were evaluated by Northern blot analysis using cDNA of A. thaliana FDH prepared by cloning on the basis of known sequence. As a result, expression of the FDH gene in A. thaliana was not intensely influenced by formic acid, an inherent substrate for FDH, but strongly induced by its reduced form, formaldehyde.     

Catalytic graphitization of an amorphous carbon film under focused electron beam irradiation due to the presence of sputtered nickel metal particles

Electron beam irradiation of Ni particles (diameter: ∼500 nm) in a transmission electron microscope (TEM) formed small secondary particles, which moved randomly on an amorphous carbon film. Catalytic graphitization occurred along the path traced by the moving particles. It is generally well known that heat treatment is needed to produce catalytic graphitization of an amorphous carbon. However, we rapidly produced catalytic graphitization in the presence of sputtered Ni particles by focused electron beam irradiation in the TEM although no external heating was employed.     

Site and sample dependent electron-phonon coupling of Eu ions in epitaxial-grown GaN layers

The incorporation of Eu ions into GaN has been studied using combined excitation-emission spectroscopy for samples that were in situ doped during organometallic vapor-phase epitaxy (OMVPE) growth. The obtained fingerprints of characteristic emission spectra are subsequently used to determine the coupling of the Eu ions to the crystal lattice. We find a majority site, which exhibits coupling to bulk-like phonon modes as well as a localized phonon mode. For this site, we also find that the zero-phonon line of the ⁷F₀ to ⁵D₀ transition, which is forbidden, is much weaker than the phonon-coupled excitation transitions. The ratio of zero-phonon to phonon-coupled transition strength depends on the crystalline quality of the layer. These observations are consistent with the assignment of the majority site to an unperturbed Eu ion on Ga position. We find that the relative abundance of the majority site is strongly underestimated whenever the zero-phonon ⁷F₀ to ⁵D₀ excitation transition is used as a measure.