Two experiments investigated the mental representation of spatial descriptions. In Experi· ment 1, the subjects classified a series of diagrams, each presented after a spatial description, as either consistent or inconsistent with the description. They were then given an unexpected recognition test of their memory for the descriptions. The subjects remembered the meanings of determinate descriptions very much better than those of grossly indeterminate descriptions; their memory for a description was not reliably affected by whether or not the diagram had been consistent with it. Experiment 2 extended these findings and showed that, although the semantic implications of a determinate description are better remembered than are those of an indeterminate description, the verbatim details of an indeterminate description are easier to recall than are those of a determinate description. The results are taken to imply the existence of two different sorts of encoding: propositional representations that are relatively hard to remember but correspond closely to the sentences in the description, and mental models that are relatively easy to remember but are analogous to spatial arrays and accordingly poor in linguistic detail.

To understand the complex drought response mechanism in crop plants, a systematic root proteomics approach was adopted to identify and analyze the expression patterns of differentially expressed major root proteins of Vigna radiata during short-term (3 days) and consecutive long-term water-deficit (6 days) as well as during recovery (6 days after re-watering). Photosynthetic gas exchange parameters of the plant were measured simultaneously during the stress treatment and recovery period. A total of 26 major protein spots were successfully identified by mass spectrometry, which were grouped according to their expression pattern during short-term stress as significantly up-regulated (9), down-regulated (10), highly down-regulated, beyond detection level of the software (2) and unchanged (5). The subsequent changes in the expression patterns of these proteins during long-term stress treatment and recovery period was analyzed to focus on the dynamic regulation of these functionally important proteins during progressive drought and recovery period. Cytoskeleton-related proteins were down-regulated initially (3d) but regained their expression levels during subsequent water-deficit (6d) while glycoprotein like lectins, which were primarily known to be involved in legume-rhizobia symbiosis, maintained their enhanced expression levels during both short and long-term drought treatment indicating their possible role in drought stress response of legumes. Oxidative stress-related proteins including Cu/Zn superoxide dismutase, oxidoreductase and aldehyde reductase were also up-regulated. The analyses of the dynamic regulation of these root proteins during short- and long-term water-deficit as well as recovery period may prove crucial for further understanding of drought response mechanisms in food legumes.

Proteinase inhibitors (C11PI) from mature dry seeds of Cajanus cajan (cv. ICP 7118) were purified by chromatography which resulted in 87-fold purification and 7.9% yield. SDS-PAGE, matrix assisted laser desorption ionization time-of-flight (MALDI-TOF/TOF) mass spectrum and two-dimensional (2-D) gel electrophoresis together resolved that C11PI possessed molecular mass of 8385.682 Da and existed as isoinhibitors. However, several of these isoinhibitors exhibited self association tendency to form small oligomers. All the isoinhibitors resolved in Native-PAGE and 2-D gel electrophoresis showed inhibitory activity against bovine pancreatic trypsin and chymotrypsin as well as Achaea janata midgut trypsin-like proteases (AjPs), a devastating pest of castor plant. Partial sequences of isoinhibitor (pI 6.0) obtained from MALDI-TOF/TOF analysis and N-terminal sequencing showed 100% homology to Bowman-Birk Inhibitors (BBIs) of leguminous plants. C11PI showed non-competitive inhibition against trypsin and chymotrypsin. A marginal loss (<15%) in C11PI activity against trypsin at 80 (°)C and basic pH (12.0) was associated with concurrent changes in its far-UV CD spectra. Further, in vitro assays demonstrated that C11PI possessed significant inhibitory potential (IC50 of 78 ng) against AjPs. On the other hand, in vivo leaf coating assays demonstrated that C11PI caused significant mortality rate with concomitant reduction in body weight of both larvae and pupae, prolonged the duration of transition from larva to pupa along with formation of abnormal larval-pupal and pupal-adult intermediates. Being smaller peptides, it is possible to express C11PI in castor to protect them against its devastating pest A. janata.

Silkworm, Bombyx mori, vitellogenin (Vg) was isolated from perivisceral fat body of day 3 of pupa. Both Vg subunits were co-purified as verified by mass spectrometry and immunoblot. Purified Vg responded to specific tests for major posttranslational modifications on native gels indicating its nature as lipo-glyco-phosphoprotein. The Vg fraction had strong antibacterial activity against Gram negative bacterium Escherichia coli and Gram positive bacterium Bacillus subtilis. Microscopic images showed binding of Vg to bacterial cells and their destruction. When infected silkworm larvae were treated with purified Vg they survived the full life cycle in contrast to untreated animals. This result showed that Vg has the ability to inhibit the proliferation of bacteria in the silkworm fluid system without disturbing the regular metabolism of the host.

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Developing efficient ways to control the nanocluster properties and synthesize atomically precise metal nanoclusters are the foremost goals in the field of metal nanocluster research. In this article, we demonstrate that the direct synthesis of atomically precise, hydrophilic metal nanoclusters as well as tuning of their properties can be achieved by an appropriate selection of reactants, binding ligand, and their proportions. Thus, a facile, single-step method has been developed for the direct synthesis of Au(SCHCOH) nanocluster in an aqueous medium under ambient conditions. The synthesis does not require any pH or temperature control and postsynthesis size-separation step. The use of a hydrophilic, bifunctional short carbon-chain capping ligand, HSCHCOH, allows tuning of cluster properties such as the photoluminescence and stability in an aqueous medium via the variation of pH of the cluster solution. By using a phase transfer catalyst, the nanoclusters can also be transferred into toluene solvent, which further enhances the nanocluster photoluminescence. The formation, composition, and purity of the product clusters have been characterized by using a number of methods such as the polyacrylamide gel electrophoresis, UV-visible and FTIR spectroscopies, transmission electron microscopy, energy dispersive X-ray analysis, thermogravimetric analysis, X-ray photoelectron spectroscopy, and matrix-assisted laser desorption ionization-time-of-flight mass spectrometry. Gold nanoclusters with properties such as water solubility, water-to-organic phase-transfer ability, and tunable stability and photoluminescence are promising for various studies and applications. The work reveals a few principles that can be helpful in the development of a general toolbox for the rational design of size-selective synthesis and properties tuning of the metal nanoclusters.

Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial blight disease in rice and brutally affects the yield up to 50 % of total production. Here, we report a comparative proteomics analysis of total foliar protein isolated from infected rice leaves of susceptible Pusa Basmati 1 (PB1) and resistant Oryza longistaminata genotypes. Two-dimensional gel electrophoresis (2-DE) coupled with matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) approaches identified 29 protein spots encoding unique proteins from both the genotypes. Identified proteins belonged to a large number of biological and molecular functions related to biotic and abiotic stress proteins which are potentially involved during Xoo infection. Biotic and abiotic stress-related proteins were induced during Xoo infection, indicating the activation of common stress pathway during bacterial blight infection. Candidate genes conferring tolerance against bacterial blight, which include germin-like protein, putative r40c1, cyclin-dependent kinase C, Ent-isokaur-15-ene synthase and glutathione-dependent dehydroascorbate reductase 1 (GSH-DHAR1), were also induced, with germin-like proteins induced only in the resistant rice genotype O. longistaminata. Energy, metabolism and hypothetical proteins were common among both the genotypes. Further, host defence/stress-related proteins were mostly expressed in resistant genotype O. longistaminata, indicating possible co-evolution of the pathogen and the wild rice, O. longistaminata.

Dudgeodes bharathidasani sp. nov. is described from the Western Ghats of South India. The nymphs of this species were found in the seepage areas of a stream, and they were associated with the nets constructed by trichopteran larvae (Hydropsychidae: Hydropsyche).