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Insect growth and development are precisely controlled by hormone homeostasis. The prothoracicotropic hormone (PTTH) receptor, Torso, is a member of the receptor tyrosine kinase family in insects. Activation of Torso by PTTH triggers biosynthesis and release of the steroid hormone in the prothoracic gland (PG). Although numbers of genes functioning in steroid hormone synthesis and metabolism have been identified in insects, the PTTH transduction pathway via its receptor Torso is poorly understood. In the current study, we describe a loss‐of‐function analysis of Torso in the silkworm, Bombyx mori, by targeted gene disruption using the transgenic CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/RNA‐guided Cas9 nucleases) system. Depletion of B. mori Torso (BmTorso) did not eventually affect larval ecdysis and metamorphosis processes. Instead, BmTorso deficiency resulted in significant extension of developing time during larval and pupal stages with increased pupa and cocoon sizes. The ecdysteriod titers in the hemolymph of BmTorso mutants sharpy declined. Transcriptional levels of genes involved in ecdysone biosynthesis and ecdysteroid signaling pathways were significantly reduced in BmTorso‐deficient animals. Additionally, RNA‐Seq analysis revealed that genes involved in the longevity pathway and protein processing in the endoplasmic reticulum pathway were affected after BmTorso deletion. These results indicate that Torso is critical for maintaining steroid hormone homeostasis in insects. [ABSTRACT FROM AUTHOR]

In a sample of 455 Taiwanese upper‐secondary school students, latent variable structural equation modeling was used to test hypothesized relationships between beliefs about knowledge in science, beliefs about justification for knowing in science, and justification of knowledge claims concerning science encountered on the Internet. Results indicated that participants displayed adaptive beliefs in the tentative and evolving nature of scientific knowledge while their beliefs about justification for knowing in science seemed somewhat less adaptive. Further, their self‐reports of Internet‐specific justification of knowledge claims suggested that they did not strongly believe that science information posted on the Internet needed to be carefully evaluated. The structural equation modeling indicated that beliefs in the tentative and evolving nature of scientific knowledge had direct positive relationships with beliefs in justification by research‐based authority and justification by multiple sources in science, which, in turn, mediated the relationships between beliefs in tentative and evolving knowledge and adaptive beliefs about Internet‐specific justification of knowledge claims. Beliefs in the unambiguous, certain nature of scientific knowledge had a direct positive relationship with beliefs in justification by school‐based authority (i.e., the science teacher and the science textbook), but beliefs in justification by school‐based authority were not related to Internet‐specific justification beliefs. We highlight the unique contributions of this study to the field of epistemic belief and science education research, and its theoretical and educational implications are discussed. [ABSTRACT FROM AUTHOR]

The main goal of this study was to investigate how readers' visual attention distribution during reading of conflicting science information is related to their scientific reasoning behavior. A total of 25 university students voluntarily participated in the study. They were given conflicting science information about earthquake predictions to read while their eye movements during reading were recorded by the FaceLAB eye tracking system. After reading, the participants were interviewed to probe their reasoning performance. Our study showed that when university students were asked to read and reason about conflicting science information, those who paid more cognitive attention and efforts to the text areas related to backing theory, data, and warrants demonstrated better performances in coordinating theory and evidence, identifying evidence, and providing rebuttals, compared to students who paid less attention and made fewer cognitive efforts to these areas. The association between students' background knowledge and performance of scientific reasoning was weak. Compared to those with irrelevant backgrounds, students with relevant background knowledge tended to read more of the facts when the science information involved a simple experimental study, while their attention was directed more to data and claims when the experimental study was complicated or unfamiliar. © 2017 Wiley Periodicals, Inc. J Res Sci Teach 10: 1347-1372, 2017 [ABSTRACT FROM AUTHOR]