Chain stiffness and chain conformation of poly(α-methylene-γ-butyrolactone) in dilute solutions

The chain stiffness and local chain conformation of atactic poly(α-methylene-γ-butyrolactone) (PMBL), which is a side chain cyclic structural analog of poly(methyl methacrylate) (PMMA), with a weight-average molecular weight (M_w) ranging from 2.8 × 10³ to 2.6 × 10⁶ in N,N-dimethylformamide (DMF) and γ-butyrolactone (GBL) were characterized by size exclusion chromatography with a multi-angle light-scattering detector (SEC-MALS) and synchrotron radiation small-angle X-ray scattering (SAXS). Based on the Kratky-Porod worm-like chain model, the scattering functions and the M_w dependence of z-average root-mean-square radius of gyration <S²>_z^1/2 yielded the Kuhn segment lengths λ⁻¹, the diameter of the PMBL chains d, and the excluded-volume strengths in DMF and GBL. The local conformation of atactic PMBL in DMF and GBL were slightly larger than those of atactic PMMA, due to the presence of the conformationally rigid lactone ring structure.     

Kinetics of CO2 reforming of methane by catalytically activated metallic foam absorber for solar receiver-reactors

Ni–Cr–Al metallic foam absorber with high porosity was catalytically activated using a Ru/γ-Al₂O₃ catalyst, and was subsequently tested with respect to CO₂ reforming of methane in a small-scale volumetric receiver-reactor by using a sun-simulator. A chemical storage efficiency of 37% was obtained for a mean light flux of 325 kW m⁻². Furthermore, the activity and the stability of the metallic foam absorber were compared with those of a SiC foam absorber activated with the same Ru/γ-Al₂O₃ catalyst for 50 h of light irradiation, and it was found that the metallic foam absorber has superior catalytic stability in comparison to the SiC form absorber. In addition, unlike ceramic foams such as SiC, metallic foams feature superior plasticity, which prevents the emergence of cracks caused by mechanical or thermal shock.     

Addition polymerization of norbornene, 5-vinyl-2-norbornene and 2-methoxycarbonyl-5-norbornene with a catalyst based on a palladium(0) precursor complex

Pd(dibenzylideneacetone)₂, when activated in situ with 1 equiv of [CPh₃][B(C₆F₅)₄] in the presence of 1 equiv of P(C₆H₁₁)₃, efficiently catalyzed the addition polymerization and copolymerization of norbornene and its derivatives. Homopolymerization of 5-vinyl-2-norbornene took place regio-selectively with the endo-cyclic double bond to give high-molecular weight polymers, while the exocyclic double bond remained intact so that the resulting polymer had pendent vinyl groups along the polymer chain. In the polymerization of a mixture of the endo-/exo- isomers of 2-methoxycarbonyl-5-norbornene, the endo-isomer was consumed prior to consumption of the exo-isomer, contrary to the well-known tendency in Pd(II)-based catalyst systems. Another notable feature of the present catalytic system was the strong dependency of the molecular weight on the reaction temperature, which was studied in detail for the copolymerization of 2-methoxycarbonyl-5-norbornene with norbornene: we could control the molecular weight without the use of a chain transfer agent. The extracted oligomeric fraction of poly(norbornene) showed the presence of a terminal CC double bond as well as a C₆F₅ unit that was bound to the first norbornane unit in the polymer chain.     

Electro-mechanical coupling in ionic gels

An ionic-polymer–metal-composite film shows electro-mechanical coupling. When the film is bent, electric current is induced. Measurement of the induced current indicates that the current depends on the speed of bending, but the total amount of the charge transferred across the film is independent of the speed, and depends only on the magnitude of the bending. The result indicates that in addition to previously proposed dynamical coupling effect, there is a static electro-mechanical coupling effect. Mathematical model is proposed to describe this phenomena.     

Predictive factors of psychological disorder development during recovery following SARS outbreak.

Objective: To investigate strategies for broad mass isolation during outbreaks of infectious diseases. Design: A survey using a self-administered questionnaire was conducted on 300 printing company workers in Beijing, China, which was under mass isolation following the 2003 SARS outbreak, in the 7-8 months after the isolation was lifted. Main Outcome Measures: Individuals with psychological disorders were classified on the basis of scores on the 30-item General Health Questionnaire during the recovery period. Psychological disorders were observed in 49 of 187 respondents (26.2%; 95% CI = 20.2, 32.7). Results: The predicting factor with the highest correlation was income reduction, with an odds ratio of 25.0. Other items obtained were gender, range of activities, eating restrictions, restrictions in going out, disinfection of clothing, and infection control, with odds ratios of 3.2, 5.5, 3.9, 3.2, 0.2, and 0.1, respectively, and the contribution ratio was 87.7%. Conclusion: Securing income is suggested to be important in future strategies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

User Modeling in Spoken Dialogue Systems to Generate Flexible Guidance

We address the issue of appropriate user modeling to generate cooperative responses to users in spoken dialogue systems. Unlike previous studies that have focused on a user’s knowledge, we propose more generalized modeling. We specifically set up three dimensions for user models: the skill level in use of the system, the knowledge level about the target domain, and the degree of urgency. Moreover, the models are automatically derived by decision tree learning using actual dialogue data collected by the system. We obtained reasonable accuracy in classification for all dimensions. Dialogue strategies based on user modeling were implemented on the Kyoto City Bus Information System that was developed at our laboratory. Experimental evaluations revealed that the cooperative responses adapted to each subject type served as good guides for novices without increasing the duration dialogue lasted for skilled users.     

Flexible microelectronics: New application for thin‐film transistors in fingerprint sensors

Abstract— Thin‐film transistors (TFTs) are field‐effect transistors that can be used to create large‐scale‐integrated (LSI) circuits. The combination of high‐performance TFTs and transfer technology of the TFTs has the potential to foster the rise of a new flexible microelectronics industry. This paper discusses the current status of flexible microelectronics, using a TFT fingerprint sensor (FPS) as an example. Technology used in active‐matrix displays can easily be applied to the TFT FPS. TFT technology should not be confined to the display industry; its use should be expanded into the semiconductor industry. With the result presented in this paper, we declare a new era of flexible microelectronics open.     

A relation between edit distance for ordered trees and edit distance for Euler strings

We consider a relationship between the unit cost edit distance for two rooted ordered trees and the unit cost edit distance for the corresponding Euler strings. We show that the edit distance between trees is at least half of the edit distance between the Euler strings and is at most 2h+1 times the edit distance between the Euler strings, where h is the minimum height of two trees. The result can be extended for more general cost functions.     

Prognostic predictor with multiple fuzzy neural models using expression profiles from DNA microarray for metastases of breast cancer

Gene expression profiling data from DNA microarray were analyzed using the fuzzy neural network (FNN) modeling method for predicting the distant metastases of breast cancer. The best model consisting of five genes was able to predict metastases of breast cancer with 94% accuracy. Furthermore, 100% accuracy was achieved by majoritarian decision using only 25 genes from five noninferior models which were constructed independently. From the constructed model, gene expression rules, which may cause distant metastases, were explicitly extracted and 60% of the metastases cases could be explained by this rule. The FNN modeling method described in this paper enables precise extraction of significant biological markers affecting prognosis without prior knowledge.