Stage effects of negative emotion on spatial and verbal working memory

Background  

The effects of negative emotion on different processing periods in spatial and verbal working memory (WM) and the possible brain mechanism of the interaction between negative emotion and WM were explored using a high-time resolution event-related potential (ERP) technique and time-locked delayed matching-to-sample task (DMST).     

南极假丝酵母在纳米聚苯乙烯上的共价固载及其在微波辅助酯化反应中的应用（英文）

Nanopolystyrene was used as a solid support for the covalent immobilization of Candida antarctica lipase B(Cal B) using the photoreactive reagent 1‐fluoro‐2‐nitro‐4‐azido benzene(FNAB) as a cou‐pling reagent. The obtained derivative was then used as a biocatalyst in a microwave assisted ester‐ification experiment. Factors such as contact time, pH, and enzyme concentration were investigated during immobilization. The hydrolytic activity, thermal, and operational stability of immobi‐lized‐Cal B were determined. The maximum immobilized yield(218 μg/mg support) obtained at pH 6.8 exhibited optimum hydrolytic activity(4.42 × 103 mU p‐nitrophenol/min). The thermal stability of Cal B improved significantly when it was immobilized at pH 10, however, the immobilized yield was very low(93.6 μg/mg support). The immobilized‐Cal B prepared at pH 6.8 and pH 10 retained 50% of its initial activity after incubation periods of 14 and 16 h, respectively, at 60 °C. The opera‐tional stability was investigated for the microwave assisted esterification of oleic acid with metha‐nol. Immobilized‐Cal B retained 50% of its initial activity after 15 batch cycles in the micro‐wave‐assisted esterification. The esterification time was notably reduced under microwave irradia‐tion. The combined use of a biocatalyst and microwave heating is thus an alternative total green synthesis process.     

Polymerizations Mediated by Well‐Defined Rhodium Complexes

This Minireview details the current state‐of‐the‐art relating to (co)polymerizations mediated by well‐defined Rh^I‐ethynyl, vinyl, and aryl complexes. In particular, we focus on Rh^I species suitable for the (co)polymerization of phenylacetylenes, arylisocyanides, as well as propargyl esters and amides.     

Dynamics of water confined in single- and double-wall carbon nanotubes

Using high-resolution quasielastic neutron scattering, we investigated the temperature dependence of single-particle dynamics of water confined in single- and double-wall carbon nanotubes with the inner diameters of 14+/-1 and 16+/-3 A, respectively. The temperature dependence of the alpha relaxation time for water in the 14 A nanotubes measured on cooling down from 260 to 190 K exhibits a crossover at 218 K from a Vogel-Fulcher-Tammann law behavior to an Arrhenius law behavior, indicating a fragile-to-strong dynamic transition in the confined water. This transition may be associated with a structural transition from a high-temperature, low-density (<1.02 gcm(3)) liquid to a low-temperature, high-density (>1.14 gcm(3)) liquid found in molecular dynamics simulation at about 200 K. However, no such dynamic transition in the investigated temperature range of 240-195 K was detected for water in the 16 A nanotubes. In the latter case, the dynamics of water simply follows a Vogel-Fulcher-Tammann law. This suggests that the fragile-to-strong crossover for water in the 16 A nanotubes may be shifted to a lower temperature.     

Gas chromatography—mass spectrometry analysis of termite defence secretions in the subfamilyNasutitermitinae

Summary Mono- and diterpenoid components of severalNasutitermitinae soldier secretions have been characterised by gas chromatographymass spectrometry. Patterns in monoterpene distribution are useful, but not sufficient for chemotaxonomic purposes without determination of the diterpene distribution. Diterpenoids are structurally complex and can have tetracyclic, tricyclic and bicyclic skeletal structures with various degrees of oxygenation. The relative retention indices for several identified diterpenoid compounds have been determined on OV-1 and OV-17 columns. The amount and distribution of the terpenoid components are useful aids to chemotaxonomy forNasutitermitinae termites.

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Gaschromatographisch-massenspektrometrische Analyse der Verteidigungs-Sekrete der Termiten-Subfamilie Nasutitermitinae

Zusammenfassung Mono- und Diterpenderivate in den Sekreten verschiedenerNasutitermitinae-Soldaten wurden mit Hilfe der Gaschromatographie-Massenspektro-metrie charakterisiert. Verteilungsmuster der Monoterpene sind nützlich, aber für chemotaxonomische Zwecke ohne Bestimmung der Diterpen-Verteilung nicht ausreichend. Diterpenabkömmlinge sind in struktureller Hinsicht komplex und haben tetracyklische, tricyklische und bicyklische Strukturen mit wechselndem Sauerstoffgehalt. Die relativen Retentionsindices für einzelne identifizierte Diterpenabkömmlinge wurden auf OV-1- und OV-17-Säulen bestimmt. Menge und Verteilung der Terpenabkömmlinge sind nützliche Hilfsmittel für die Chemotaxonomie der genannten Termiten.

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Presented at the 8th International Microchemical Symposium, Graz, August 25–30, 1980.