The effects of speech production and vocabulary training on different components of spoken language performance

A group of 21 hard-of-hearing and deaf children attending primary school were trained by their teachers on the production of selected consonants and on the meanings of selected words. Speech production, vocabulary knowledge, reading aloud, and speech perception measures were obtained before and after each type of training. The speech production training produced a small but significant improvement in the percentage of consonants correctly produced in words. The vocabulary training improved knowledge of word meanings substantially. Performance on speech perception and reading aloud were significantly improved by both types of training. These results were in accord with the predictions of a mathematical model put forward to describe the relationships between speech perception, speech production, and language measures in children (Paatsch, Blamey, Sarant, Martin, & Bow, 2004). These training data demonstrate that the relationships between the measures are causal. In other words, improvements in speech production and vocabulary performance produced by training will carry over into predictable improvements in speech perception and reading scores. Furthermore, the model will help educators identify the most effective methods of improving receptive and expressive spoken language for individual children who are deaf or hard of hearing.     

A microfluidic platform for measuring electrical activity across cells

In this paper, we present a microfluidic chip that is capable of measuring electrical conductance through gap junction channels in a 2-dimensional cell sheet. The chip utilizes a tri-stream laminar flow to create a non-conductive sucrose gap between the two conducting solutions so that electrical current can pass across the sucrose gap only through the cells. Using the chip, we tested the effect of a gap junction inhibitor, 2-APB, on the electrical coupling of connexin 43 (Cx43) gap junction channels in NRK-49F cells. We found that 2-APB reversibly blocks the conductivity in a dose-dependent manner. The tri-stream chip further allows us to simultaneously follow the conductance changes and dye diffusion in real time. We show that 2-APB affects both conductance and diffusion, supporting the interpretation that both sets of data reflect the same gap junction activity. The chip provides a generic platform to investigate gap junction properties and to screen drugs that may inhibit or potentiate gap junction transmission.     

Examining Hispanic Student Mathematics Performance on High-Stakes Tests: An Examination of One Urban School District in Colorado

Hispanic students, born both inside and outside the United States, comprise over 80% of the US English language learner population. The difference in mathematics achievement among Hispanic students and other populations has been well documented. As a result, it is important to understand the effects of using standards-based mathematics curriculum with high school Hispanic students. Mathematics achievement scores from the Colorado Student Assessment Program and Measurement of Academic Progress for Hispanic 9th and 10th grade students (n = 1,318) who used the Core-Plus Mathematics Program were compared to the progress of other student demographics (n = 2,003) who used the same curriculum. In following the recommendations of the National Research Council (On evaluation curricular effectiveness: judging the effectiveness of K-12 mathematics evaluations. National Academies Press, Washington, DC 2005), a meta-analysis (Glass in Educ Res 5:3–8, 1976) of Hispanic students using National Science Foundation Funded (NSFF) curricula was conducted to contextualize this study’s findings within the findings of previous studies. The results of this study indicated that Hispanic students have shown modest gains; however, their relative position compared to other ethnic groups is unremarkable. The meta-analysis Cohen’s d results ranged from +.673 (SE = .131) to −.670 (SE = .045) with slightly positive effects for Hispanic students using an NSFF curriculum when compared to those not using an NSFF curriculum (.043, SE = .012).     

名辩逻辑提纲(上)

构建中国逻辑的横向体系，编写出教科书式的中国逻辑读本，是一项极具意义的学术工程。《提纲》乃这方面的闯新之作，计有“绪论”“概念”“辩说”“余论”四章。“概念”“辩说”叙说中国逻辑的两大支柱部分；“绪论”“余论”阐述中国逻辑的总体、总貌和特色     

Effect of the addition of hydroxyl-terminated polydimethylsiloxane to TEOS-based stone consolidants

Hybrid stone consolidants prepared from tetraethoxysilane (TEOS) and α,ω-hydroxyl-terminated polydimethylsiloxane (PDMS-OH) have been considered as one of the most promising approaches to improve the effectiveness of traditional alkoxysilane-based formulations. They have emerged as response to the negative reports commonly found in the literature: the resulting silica gel phase (SiO₂) tends to develop fractures and fissures inside the stone as the gel shrinks during the drying stage. In this work, we employed SEM, solid-state ²⁹Si NMR spectroscopy and compressive tests to characterize SiO₂-PDMS hybrid gels. We report the morphological characteristics exhibited by gels prepared in vitro and in situ. It was found an appreciable reduction of gel fracture for hybrids prepared from 5% w/w of PDMS. As TEOS polycondenses, PDMS-OH is chemically incorporated into the gel matrix via Si-O-Si bonds. The inclusion of these elastic chains provides the necessary flexibility to resist the stress imposed by capillary pressure. Additionally, an important hydrophobic character is imparted to the stone.     

Tunable visual color filter using microfluidic grating

This paper reports a tunable visual color filter based on a microfluidic transmission grating. The grating lines are formed by the microflows in an array of evenly spaced straight microchannels. In experimental study, the transmission of white light measures a shift of visual color from red to blue in the zeroth order diffraction in response to a change of the refractive index from 1.3290 to 1.3782 in the microflows. The merit of large tunability of transmission peak (Δλ=408 nm) makes this grating potential for various applications in biological and chemical measurements, such as space- and time-resolving micropattern spectrophotometers and separation of the fluorescence from the excitation.