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Some evidence suggests that the written production of single words involves not only the ordered retrieval of individual letters, but that abstract, higher-level linguistic properties of the words also influence responses. We report five experiments using the "implicit priming" task adopted from the spoken domain to investigate response preparation of written responses. The first three experiments demonstrate a priming effect due to shared graphemes which is independent of phonological overlap. Two further experiments show that the priming effect is largely immune to allographic variation, but that it disappears when overlapping word-initial letters are embedded within different graphemes. In combination, the results suggest that preparation of handwritten word production involves an abstract graphemic level of representation, mediating between the retrieval of orthographic word forms and individual letters. (Contains 1 table and 1 figure.)

When people read temporarily ambiguous sentences, there is often an increased prevalence of regressive eye-movements launched from the word that resolves the ambiguity. Traditionally, such regressions have been interpreted at least in part as reflecting readers' efforts to re-read and reconfigure earlier material, as exemplified by the Selective Reanalysis hypothesis [Frazier, L., & Rayner, K. (1982). Making and correcting errors during sentence comprehension: Eye movements in the analysis of structurally ambiguous sentences. "Cognitive Psychology", 14, 178-210]. Within such frameworks it is assumed that the selection of saccadic landing-sites is "linguistically supervised". As an alternative to this proposal, we consider the possibility (dubbed the Time Out hypothesis) that regression control is partly decoupled from linguistic operations and that landing-sites are instead selected on the basis of low-level spatial properties such as their proximity to the point from which the regressive saccade was launched. Two eye-tracking experiments were conducted to compare the explanatory potential of these two accounts. Experiment 1 manipulated the formatting of linguistically identical sentences and showed, contrary to purely linguistic supervision, that the landing site of the first regression from a critical word was reliably influenced by the physical layout of the text. Experiment 2 used a fixed physical format but manipulated the position in the display at which reanalysis-relevant material was located. Here the results showed a highly reliable linguistic influence on the overall distribution of regression landing sites (though with few effects being apparent on the very first regression). These results are interpreted as reflecting mutually exclusive forms of regression control with fixation sequences being influenced both by spatially constrained, partially decoupled supervision systems as well as by some kind of linguistic guidance. The findings are discussed in relation to existing computational models of eye-movements in reading. (Contains 6 figures and 2 tables.)

Diapause is an important characteristic of insects used to adapt to extreme changes in environmental conditions. Embryonic diapause of the bivoltine silkworm (Bombyx mori) is determined by environmental conditions experienced by the mother while in the embryo stage. If they are incubated at 25°C with natural light, their progenies will be diapause‐destined. If they are incubated at 17°C in darkness, their progenies will be non‐diapause‐destined. The molecular mechanism of diapause remains unknown. In the present study, we analyzed two downregulated genes (BGIBMGA003835, BGIBMGA012335) and two upregulated genes (BGIBMG012996, BGIBMG002426) related to carbohydrate metabolism, verified differentially expressed in ovaries and heads of 1‐day‐old fifth‐instar larvae to 6‐day pupae by quantitative real‐time reverse transcription polymerase chain reaction (qRT‐PCR). In line with published data, the expression level of these genes in larvae were generally lower than in pupae. We further analyzed the expression levels of the four genes in BmN cells that had been treated with various concentrations of diapause hormone (DH). It demonstrated that the expression of these genes was affected by DH. Knockdown of the selected genes in non‐diapause‐destined female pupae changed the fate of the progeny from non‐diapause‐ to daipause‐destined, as seen by the appearance of diapause eggs. Our study provides insight into the molecular mechanism of diapause in B. mori. The expression levels of BGIBMGA003835, BGIBMGA012335, BGIBMG012996 and BGIBMG002426 were different at diverse developmental stages. They can also be influenced by Bmo‐DH. RNAi if several genes can turn over the fate of non‐diapause eggs. [ABSTRACT FROM AUTHOR]

Molting is an important physiological process in the larval stage of Bombyx mori and is controlled by various hormones and peptides. The silkworm mutant that exhibits the phenotype of non-molting in the 2nd instar (nm2) is incapable of molting in the 2nd instar and dies after seven or more days. The ecdysone titer in the nm2 mutant is lower than that in the wildtype, and the mutant can be rescued by feeding with 20E and cholesterol. The results of positional cloning indicated that structural alteration of BmCPG10 is responsible for the phenotype of the nm2 mutant. To explore the possible relationship between BmCPG10 and the ecdysone titer as well as the genes affected by BmCPG10, digital gene expression (DGE) profile analysis was conducted in the nm2 mutant, with the wildtype strain C603 serving as the control. The results revealed 1727 differentially expressed genes, among which 651 genes were upregulated and 1076 were downregulated in nm2. BLASTGO analysis showed that these differentially expressed genes were involved in various biological processes, cellular components and molecular functions. KEGG analysis indicated an enrichment of these differentially expressed genes in 240 pathways, including metabolic pathways, pancreatic secretion, protein digestion and absorption, fat digestion and absorption and glycerolipid metabolism. To verify the accuracy of the DGE results, quantitative reverse transcription PCR (qRT-PCR) was performed, focusing on key genes in several related pathways, and the results were highly consistent with the DGE results. Our findings indicated significant differences in cuticular protein genes, ecdysone biosynthesis genes and ecdysone-related nuclear receptors genes, but no significant difference in juvenile hormone and chitin biosynthesis genes was detected. Our research findings lay the foundation for further research on the formation mechanism of the nm2 mutant. [ABSTRACT FROM AUTHOR]

A new purple quail-like (q-lp) mutant found from the plain silkworm strain 932VR has pigment dots on the epidermis similar to the pigment mutant quail (q). In addition, q-lp mutant larvae are inactive, consume little and grow slowly, with a high death rate and other developmental abnormalities. Pigmentation of the silkworm epidermis consists of melanin, ommochrome and pteridine. Silkworm development is regulated by ecdysone and juvenile hormone. In this study, we performed RNA-Seq on the epidermis of the q-lp mutant in the 4th instar during molting, with 932VR serving as the control. The results showed 515 differentially expressed genes, of which 234 were upregulated and 281 downregulated in q-lp. BLASTGO analysis indicated that the downregulated genes mainly encode protein-binding proteins, membrane components, oxidation/reduction enzymes, and proteolytic enzymes, whereas the upregulated genes largely encode cuticle structural constituents, membrane components, transport related proteins, and protein-binding proteins. Quantitative reverse transcription PCR was used to verify the accuracy of the RNA-Seq data, focusing on key genes for biosynthesis of the three pigments and chitin as well as genes encoding cuticular proteins and several related nuclear receptors, which are thought to play key roles in the q-lp mutant. We drew three conclusions based on the results: 1) melanin, ommochrome and pteridine pigments are all increased in the q-lp mutant; 2) more cuticle proteins are expressed in q-lp than in 932VR, and the number of upregulated cuticular genes is significantly greater than downregulated genes; 3) the downstream pathway regulated by ecdysone is blocked in the q-lp mutant. Our research findings lay the foundation for further research on the developmental changes responsible for the q-lp mutant. [ABSTRACT FROM AUTHOR]