Shape memory properties of polypeptide hydrogels having hydrophobic alkyl side chains

Polypeptide hydrogels were prepared by cross-linking of hydrophobically-modified poly[N⁵-(2-hydroxyethyl) l-glutamine] having alkyl side chains –C_nH_2n+1. Chain length of the alkyl group was n = 8, 16, and 18, and their mole fractions in the polypeptide were varied in the range of 0.05–0.16. Shape memory ability of the prepared polypeptide hydrogels was investigated. After deformation at 60 °C, the hydrogel was cooled in order to fix the temporary deformed shape. It was found that crystallization of the alkyl side chains did not occur, and the fixation ability of the hydrogel at 0 °C was low. In the subsequent heating process, the deformed temporary shape spontaneously recovered to the original shape gradually with increasing temperature, in other words, the shape recovery ratio varied with depending on the recovery temperature. From these observations, it was proposed that the shape fixation of the polypeptide hydrogel was achieved by strong segregation of the hydrophobic alkyl chains at low temperature, and the shape recovery of the deformed hydrogel was accompanied by the gradual decrease of the segregation strength with the temperature increase.     

First paralytic shellfish poison (PSP) infestation of bivalves due to toxic dinoflagellate Alexandrium tamiyavanichii, in the southeast coasts of the Seto Inland Sea, Japan

The mussel Mytilus edulis and the cultured ark shell Anadara broughtonii in the southeast coasts of the Seto Inland Sea were contaminated with paralytic shellfish poison (PSP) following the appearance of the dinoflagellate Alexandrium tamiyavanichii in early December 1999. A. tamiyavanichii plankton collected around the Straits of Naruto on December 3, 1999 showed PSP toxicity, of which 83 mol% was accounted for by GTX2, GTX3 and GTX4. Its specific toxicity was 112.5 fmol/cell, and one MU was equivalent to 7,200 cells. Toxicity values at the beginning of toxification were 4.7 MU/g for the ark shell and 7.3 MU/g for the mussel. In the former, the value remained at almost 4 MU/g, resulting in prohibition of marketing for about two months. In the latter, it sharply decreased to less than 4 MU/g. These bivalves collected during the toxification period were dissected into five tissues, mantle, adductor muscle, hepatopancreas, gills and "others", and submitted to high-performance liquid chromatography (HPLC). The cultured ark shell accumulated GTX2, GTX3 and STX as major components and GTX1, GTX4, GTX5, neoSTX, dcSTX and PX1-3 (C1-C3) as minor ones. The amount of GTX3 decreased with time, while STX tended to increase. At the early stage of PSP toxification, toxins were accumulated in the gills and "others", most of which were quickly detoxified. On the other hand, PSP of the toxified mussel consisted of GTX4 as a main component, and GTX1, GTX2, GTX3, GTX5, STX and PX1-2 (C1-C2) as minor ones. Its toxin composition pattern was similar to that of the ingested causative plankton. Its total toxin decreased soon after disappearance of the dinoflagellate. During the decrease of toxicity, PSP tended to be retained in the hepatopancreas, resulting in accumulation of 50 mol% of total toxin.     

Cryo preparation of isolated rabbit pancreatic islets

A Flotronic silver membrane has been used as a vehicle to process, via freeze substitution, collagenase-derived rabbit pancreatic islets. The procedure provides: (1) a simple, inexpensive method for handling larger numbers of tightly clustered islet aggregates; (2) a metal surface for rapid heat transfer from specimen to cryogen resulting in an increased circumferential zone of fine structural preservation; (3) the elimination of possible artifacts associated with impact or rotation of biological specimens against a cooled, highly polished metal block; (4) superior preservation of structural components not usually observed by conventional modes of fixation; (5) retention of metabolic components which may subsequently be available for immunocytochemical or X-ray energy dispersive procedures.     

Stalking and related behaviors experienced by counseling center staff members from current or former clients.

The incidence of stalking and stalking-related harassment experienced by university counseling center staff members was assessed by surveying a random sample of counseling centers in the United States that were accredited by the International Association of Counseling Services. Responses from 178 counseling center staff members showed that 5.6% of the sample had been stalked by a current or former client, 8% had had a family member stalked, and 10% had had a supervisee stalked. The survey also found that 64% of the sample had experienced some type of harassing behavior from a current or former client. The results are discussed in terms of implications for practice and training in university counseling centers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development of a low‐noise IGBT module

High‐frequency leakage current that may cause serious conducted EMI problems flows through an inverter system. The paths of the leakage current are stray capacitances that are formed inside of motors, cables, and IGBT modules. This paper proposes a new IGBT module that realizes low conducted emission noise by flipping the IGBT chip of the lower‐voltage side to decrease its stray capacitance. The leakage current flowing through the low‐noise IGBT module becomes small, since the stray capacitance is a main path of the current. Through an experiment, it is clarified that the conducted emission level is reduced by 13 dB at a maximum when the low‐noise IGBT module is applied to a resonant‐type inverter. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 171(4): 45–52, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20971     

Consultation system with contact person through on‐demand calling of a proper expert for a problem

Local branches of financial institutions offer to their customers a wide spectrum of advisory services which must be upgraded from time to time to keep up with changes in the mix of financial products offered and with the growing sophistication of the customers' inquiries. However, keeping the full staff of experts trained in various aspects of banking business is not practical from the standpoint of cost‐effectiveness, while without them it is difficult to provide high‐quality services. In this paper we propose a window consultation system for customers at the branch office using the on‐demand calling of an expert specializing in the subject related to the inquiry. The proposed system is based on the multimedia network technology and it has two main functions: selection of an on‐line expert and tele‐consultation providing the replies or expert advises to the inquiries. A customer visiting his branch office is interviewed by a clerk who determines the contents of the request and, if he is unable to give the customer satisfactory advice, contacts through the proposed system an appropriate expert. This system makes it possible to provide high‐quality services and to avoid mistakes, which can be made by customers if they operate the consultation systems on their own. The proposed system has a three‐layered structure: application component layer, middleware component layer, and fundamental component layer. This structure allows for an easy installation and modifications depending on the scale of specific branch offices of financial institutions and the mix of financial products offered by them. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 163(2): 57–66, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20518     

Does the conceptual distinction between singular and plural sets depend on language?

Previous studies indicate that English-learning children acquire the distinction between singular and plural nouns between 22 and 24 months of age. Also, their use of the distinction is correlated with the capacity to distinguish nonlinguistically between singular and plural sets in a manual search paradigm (D. Barner, D. Thalwitz, J. Wood, S. Yang, & S. Carey, 2007). The authors used 3 experiments to explore the causal relation between these 2 capacities. Relative to English, Japanese and Mandarin had impoverished singular–plural marking. Using the manual search task, in Experiment 1 the authors found that by around 22 months of age, Japanese children also distinguished between singular and plural sets. Experiments 2 and 3 extended this finding to Mandarin-learning toddlers. Mandarin learners who were 20–24 months of age did not yet comprehend Mandarin singular–plural marking (i.e., yige vs. yixie, or –men), yet they did distinguish between singular and plural sets in manual search. These experiments suggest that knowledge of singular–plural morphology is not necessary for deploying the nonlinguistic distinction between singular and plural sets. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A new analytical method for gonyautoxins based on postcolumn HPLC

A new ion-pairing high-performance liquid chromatography (HPLC) method on a C30 column with a volatile mobile phase was developed to separate the gonyautoxin group (GTXs) from contaminants, allowing the utilization of liquid chromatography/mass spectrometry (LC/MS) with higher performance. A mobile phase consisting of 5 mmol/L heptafluorobutyric acid and 2% acetonitrile in 10 mmol/L ammonium acetate was adopted for separation of GTXs because the C30 column strongly retains GTXs under acidic conditions. The newly adopted method could efficiently separate GTXs from contaminants, especially in the toxic short-necked clam, whereas the routine HPLC so far used has poor resolution to separate GTXs from unknown interfering substances. In our method, GTXs were eluted in the order of GTX5, GTX3, GTX4, GTX2 and GTX1 from the C30 column, and were successfully determined by sonic spray ionization mass spectrometry (SSI-MS) with high sensitivity. This method is characterized by the combination of HPLC using a fluorescence detection system for PSP, and SSI-MS for measurement of the mass number.     

Diverse in Name Only? Intercultural Interaction at a Multicultural University

This study analyzed the frequency and nature of intercultural contact among multicultural university students so as to explore the contextualized shape of intercultural interaction. Unlike past intercultural contact research, this study pushed beyond ascertaining if intercultural contact is being made to examining specific interactional details and topics that constitute already existing contact. We collected survey responses from 4 major racial/ethnic groups—Latino/as, Blacks/African Americans, Whites/European Americans, and Asian Americans—regarding the frequency and nature of intercultural interactions. The results indicate that each group engages in narrow interaction patterns with only 1 other major racial/ethnic group and that most intercultural interaction occurs on campus in class or off campus at work. In addition, it suggests that individuals define intercultural contact in different and often contradictory ways.     

Working Memory and Perseveration in Verbal Fluency.

Letter and semantic fluency tasks are often used in neuropsychological assessment and are sensitive to many conditions. Performance is assessed by correct responses and errors, including perseverations. Healthy young adults performed letter and semantic fluency tasks. One group performed these tasks in the conventional manner; 2 other groups performed them while maintaining memory loads. The memory loads consisted either of words from the same category as the fluency task or of words from a different category. The results showed little effect of memory loads on correct responses but significant effects of memory load on perseveration rates: Same-category loads resulted in higher rates, especially in letter fluency. The results are discussed in terms of frontal lobe function in verbal fluency. (PsycINFO Database Record (c) 2010 APA, all rights reserved)