Lexical frequency and neighborhood density effects on the recognition of native and Spanish-accented words by native English and Spanish listeners

This study examined the effect of presumed mismatches between speech input and the phonological representations of English words by native speakers of English (NE) and Spanish (NS). The English test words, which were produced by a NE speaker and a NS speaker, varied orthogonally in lexical frequency and neighborhood density and were presented to NE listeners and to NS listeners who differed in English pronunciation proficiency. It was hypothesized that mismatches between phonological representations and speech input would impair word recognition, especially for items from dense lexical neighborhoods which are phonologically similar to many other words and require finer sound discrimination. Further, it was assumed that L2 phonological representations would change with L2 proficiency. The results showed the expected mismatch effect only for words from dense neighborhoods. For Spanish-accented stimuli, the NS groups recognized more words from dense neighborhoods than the NE group did. For native-produced stimuli, the low-proficiency NS group recognized fewer words than the other two groups. The-high proficiency NS participants' performance was as good as the NE group's for words from sparse neighborhoods, but not for words from dense neighborhoods. These results are discussed in relation to the development of phonological representations of L2 words. (200 words).     

Spin dynamics in the carrier-doped S=1/2 triangular lattice of NaxCoO2.yH2O

We probed the local electronic properties of the mixed-valent Co+4-x triangular lattice in NaxCoO2.yH(2)O by 59Co NMR. We observed two distinct types of Co sites for x > or =1/2, but the valence seems averaged out for x approximately 1/3. Local spin fluctuations exhibit qualitatively the same trend down to approximately 100 K regardless of the carrier concentration x, and hence the nature of the electronic ground state. A canonical Fermi-liquid behavior emerges below approximately 100 K only for x approximately 1/3.     

An HPLC assay of hydroxyl radicals by the hydroxylation reaction of terephthalic acid

An HPLC assay for hydroxyl radicals is described. The hydroxyl radical was trapped by terephthalic acid (non-fluorescent), and 2-hydroxyl terephthalic acid (fluorescent) was quantitated by HPLC-fluorescence detection. At a terephthalic acid concentration of 4.25 mmol/L, the hydroxyl radical formed in the Fenton reaction was successfully assayed in the concentration range of hydrogen peroxide of 2.5-50 micro mol/L, where the concentration of Fe(II) was 50 micro mol/L. The fluorescence of 2-hydroxy terephthalate was stable at 24 h, and its detection limit by this method was 5 nmol/L (100 fmol).     

Beam-polarization asymmetries for the p(gamma-->, K+)Lambda and p(gamma-->, K+)Sigma(0) reactions for E(gamma)=1.5-2.4 GeV

Beam polarization asymmetries for the p(gamma-->,K+)Lambda and p(gamma-->,K+)Sigma(0) reactions are measured for the first time for E(gamma)=1.5-2.4 GeV and 0.6相似文献   

Limitation of immunoaffinity column for the removal of abundant proteins from plasma in quantitative plasma proteomics

In plasma proteomics, before a proteome analysis, it is essential to prepare protein samples without high‐abundance proteins, including albumin, via specific preparation techniques, such as immunoaffinity capture. However, our preliminary experiments suggested that functional changes with use alter the ability of the immunoaffinity column. Thus, in this study, to evaluate the changes of the removal ability of abundant proteins from plasma by the immunoaffinity column, plasma proteome analysis was performed for the long‐term test for the reproducibility of the affinity column using the fluorogenic derivatization–liquid chromatography–tandem mass spectrometry method combined with an IgY column. The specific adsorption for albumin decreased with an increase in the number of the column usage before its expiration date. Moreover, it was demonstrated that hydrophobic high molecular weight compounds in plasma adsorbed onto the column materials surface contributed to the functional changes from specific immunoaffinity adsorption into hydrophobic interaction. These results suggested that, in quantitative plasma proteomics studies, it is important to keep in mind the risk of not only the nonselective loss but also the changes in the adsorption ability of the immunoafinity column. Copyright © 2008 John Wiley & Sons, Ltd.     

The most favorable condition for lipid hydrolysis by Rhizopus delemar lipase in combination with a sugar–ester and alcohol W/O microemulsion system

The hydrophobic interfacial characterization of sugar–ester alcohol W/O microemulsion was investigated in order to develop a suitable design for reaction media. A W/O microemulsion system was prepared as a combination of sugar–ester, DK-ester-F-110 with alcohol as a cosolvent. The diameter of the sub-micron-sized water pool, the hydrophobicity of the water pool, and the fluidity of the micro-interface were studied to analyze the reactivity of Rhizopus delemar lipase in lipid hydrolysis. The diameter of the sub-micron sized water pool was measured by dynamic laser light scattering. It was proportional to the 0.33 power of W_soln and decayed with increasing alcohol concentration. The initial reaction rate of the hydrolysis of triolein in W/O microemulsion depended on the solubilized water content. The hydrophilic character of the micro-water pool was estimated from the fluorescence wavelength indicated by Coumarin 343. The maximum initial reaction rate appeared at 450–460 nm. The fluidity of the micro-interface was investigated by fluorescence anisotropy using TMA-DPH. A suitable physicochemical reaction condition for high reactivity to occur was found, satisfying both the hydrophilicity and the fluidity of the micro-interface.     

An improvement of discrete Tardos fingerprinting codes

It has been proven that the code lengths of Tardos’s collusion-secure fingerprinting codes are of theoretically minimal order with respect to the number of adversarial users (pirates). However, the code lengths can be further reduced as some preceding studies have revealed. In this article we improve a recent discrete variant of Tardos’s codes, and give a security proof of our codes under an assumption weaker than the original Marking Assumption. Our analysis shows that our codes have significantly shorter lengths than Tardos’s codes. For example, when c = 8, our code length is about 4.94% of Tardos’s code in a practical setting and about 4.62% in a certain limit case. Our code lengths for large c are asymptotically about 5.35% of Tardos’s codes. A part of this work was presented at 17th Applied Algebra, Algebraic Algorithms, and Error Correcting Codes (AAECC-17), Bangalore, India, December 16–20, 2007.