A Stochastic Theory of Exciton Transfer

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Structures of test-taking stratigies : what test-talking strategies are useful for the TOEIC reading sections?

This study explored what strategies are used when Japanese college students sit for tests. English proficiency tests such as the TOEIC or the TOEFL have been popular in recent years in Japan, both in academic and employment situations. However, few studies have examined the strategies test-takers use, while numerous studies have been conducted on general learning strategies and strategies for specific skills such as listening or speaking. This study explored the structures of test-taking strategies, especially for the TOEIC reading sections by collecting possible strategies, examining them one by one, pilot testing them and finally extracting six groups of test taking strategies using exploratory factor analysis. As a result of this study, we successfully developed a 66-item questionnaire called SITT (Strategy Inventory for Test Taking). By employing the SITT with Japanese college students, this study investigated the most and least frequently used strategies. The results indicated that metacognitive strategies were not frequently used and that specific reading strategies such as making inferences and selective attention were frequently used

Nonlinear magnetic susceptibility and aging phenomena in reentrant ferromagnet: Cu0.2_{0.2}Co0.8_{0.8}Cl2_{2}-FeCl3_{3} graphite bi-intercalation compound

Linear and nonlinear dynamic properties of a reentrant ferromagnet Cu$_{0.2}$Co$_{0.8}$Cl$_{2}$-FeCl$_{3}$ graphite bi-intercalation compound are studied using AC and DC magnetic susceptibility. This compound undergoes successive phase transitions at the transition temperatures $T_{h}$ (= 16 K), $T_{c}$ (= 9.7 K), and $T_{RSG}$ (= 3.5 K). The static and dynamic behaviors of the reentrant spin glass phase below $T_{RSG}$ are characterized by those of normal spin glass phase with critical exponent $\beta$ = 0.57 $\pm$ 0.10, a dynamic critical exponent $x$ = 8.5 $\pm$ 1.8, and an exponent $p$ (= 1.55 $\pm$ 0.13) for the de Almeida -Thouless line. A prominent nonlinear susceptibility is observed between $T_{RSG}$ and $T_{c}$ and around $T_{h}$, suggesting a chaotic nature of the ferromagnetic phase ($T_{RSG} \leq T \leq T_{c}$) and the helical spin ordered phase ($T_{c} \leq T \leq T_{h}$). The aging phenomena are observed both in the RSG and FM phases, with the same qualitative features as in normal spin glasses. The aging of zero-field cooled magnetization indicates a drastic change of relaxation mechanism below and above $T_{RSG}$. The time dependence of the absorption $\chi^{\prime \prime}$ is described by a power law form ($\approx t^{-b^{\prime \prime}}$) in the ferromagnetic phase, where $b^{\prime \prime} \approx 0.074 \pm 0.016$ at $f$ = 0.05 Hz and $T$ = 7 K. No $\omega t$-scaling law for $\chi^{\prime \prime}$ [$\approx (\omega t)^{-b^{\prime \prime}}$] is observed.Comment: 14 pages, 16 figures, and 2 table

A Single Amino Acid Mutation in SNAP-25 Induces Anxiety-Related Behavior in Mouse

Synaptosomal-associated protein of 25 kDa (SNAP-25) is a presynaptic protein essential for neurotransmitter release. Previously, we demonstrate that protein kinase C (PKC) phosphorylates Ser187 of SNAP-25, and enhances neurotransmitter release by recruiting secretory vesicles near to the plasma membrane. As PKC is abundant in the brain and SNAP-25 is essential for synaptic transmission, SNAP-25 phosphorylation is likely to play a crucial role in the central nervous system. We therefore generated a mutant mouse, substituting Ser187 of SNAP-25 with Ala using “knock-in” technology. The most striking effect of the mutation was observed in their behavior. The homozygous mutant mice froze readily in response to environmental change, and showed strong anxiety-related behavior in general activity and light and dark preference tests. In addition, the mutant mice sometimes exhibited spontaneously occurring convulsive seizures. Microdialysis measurements revealed that serotonin and dopamine release were markedly reduced in amygdala. These results clearly indicate that PKC-dependent SNAP-25 phosphorylation plays a critical role in the regulation of emotional behavior as well as the suppression of epileptic seizures, and the lack of enhancement of monoamine release is one of the possible mechanisms underlying these defects

A Method of Calculations of the Higher Order Partial Cumulants in the Problem of Low Field Resonance

A theory of low field resonance is formulated with the use of an expansion formula of the damping theory: That is, the time convolution equation is applied to this problem. In this treatment, the so-called "partial cumulants" of some what complicated structure should be calculated. To get the explicit forms of the "partial cumulants", computer calculations are preferable. The use of a computer makes it possible to treat a lot of terms and put the same class of terms into a single are. When the computer calculation is done, then the calculation time is entirely shortened and the higher order terms are treated quite easily. In this paper we present the corresponding FORTRAN programs for these calculations and give an argorism and a method to use them

A Method of Calculation for an Infinite Continued Fraction : A particular reference to static limit of exciton migration

In a stochastic model of exciton transfer, a method of dynamical coherent potential approximation (DCPA) is useful. In this treatment, a propagator (Green's function) is expressed in terms of continued fraction. In the present paper, a method of calculating the infinite continued fraction is given. The method of DCPA gives very acculate results even in the static limit compared with the conventional static CPA. Thus DCPA can treat the static phenomena as well as the dynamical properties

Basement membrane assembly of the integrin α8β1 ligand nephronectin requires Fraser syndrome–associated proteins

Dysfunction of the basement membrane protein QBRICK provokes Fraser syndrome, which results in renal dysmorphogenesis, cryptophthalmos, syndactyly, and dystrophic epidermolysis bullosa through unknown mechanisms. Here, we show that integrin α8β1 binding to basement membranes was significantly impaired in Qbrick-null mice. This impaired integrin α8β1 binding was not a direct consequence of the loss of QBRICK, which itself is a ligand of integrin α8β1, because knock-in mice with a mutation in the integrin-binding site of QBRICK developed normally and do not exhibit any defects in integrin α8β1 binding. Instead, the loss of QBRICK significantly diminished the expression of nephronectin, an integrin α8β1 ligand necessary for renal development. In vivo, nephronectin associated with QBRICK and localized at the sublamina densa region, where QBRICK was also located. Collectively, these findings indicate that QBRICK facilitates the integrin α8β1–dependent interactions of cells with basement membranes by regulating the basement membrane assembly of nephronectin and explain why renal defects occur in Fraser syndrome.©2012 Kiyozumi et al. Originally published in the Journal of Cell Biology. https://doi.org/10.1083/jcb.20120306

Polydom/SVEP1 Is a Ligand for Integrin α9β1

This research was originally published in the Journal of Biological Chemistry. Ryoko Sato-Nishiuchi, Itsuko Nakano, Akio Ozawa, Yuya Sato, Makiko Takeichi, Daiji Kiyozumi, Kiyoshi Yamazaki, Teruo Yasunaga, Sugiko Futaki and Kiyotoshi Sekiguchi. Polydom/SVEP1 Is a Ligand for Integrin α9β1. J. Biol. Chem. 2012; 287: 25615-25630 © the American Society for Biochemistry and Molecular Biolog