San Francisco State University

About: San Francisco State University is a education organization based out in San Francisco, California, United States. It is known for research contribution in the topics: Population & Planet. The organization has 5669 authors who have published 11433 publications receiving 408075 citations. The organization is also known as: San Francisco State & San Francisco State Normal School.

Role of root UV-B sensing in Arabidopsis early seedling development.

Abstract: All sun-exposed organisms are affected by UV-B [(UVB) 280–320 nm], an integral part of sunlight. UVB can cause stresses or act as a developmental signal depending on its fluence levels. In plants, the mechanism by which high-fluence-rate UVB causes damages and activates DNA-repair systems has been extensively studied. However, little is known about how nondamaging low-fluence-rate UVB is perceived to regulate plant morphogenesis and development. Here, we report the identification of an Arabidopsis mutant, root UVB sensitive 1 (rus1), whose primary root is hypersensitive to very low-fluence-rate (VLF) UVB. Under standard growth-chamber fluorescent white light, rus1 displays stunted root growth and fails to form postembryonic leaves. Experiments with different monochromatic light sources showed that rus1 phenotypes can be rescued if the seedlings are allowed to grow in light conditions with minimum UVB. We determined that roots, not other organs, perceive the UVB signal. Genetic and molecular analyses confirmed that the root light-sensitive phenotypes are independent of all other known plant photoreceptors. Three rus1 alleles have been identified and characterized. A map-based approach was used to identify the RUS1 locus. RUS1 encodes a protein that contains DUF647 (domain of unknown function 647), a domain highly conserved in eukaryotes. Our results demonstrate a root VLF UVB-sensing mechanism that is involved in Arabidopsis early seedling morphogenesis and development.

Toward Wider Use of Literature in ESL: Why and How

Abstract: use of literature in ESL can achieve, this article examines literature in terms of current ESL theory (discourse analysis, context and contextualization, schema theory, cross-cultural awareness). This is done to explain not only why literature may be a more satisfying basis for ESL learning than more commonly used texts, but also what current theory suggests about how we should exploit this form in the classroom in order to encourage interactive, communicative classes for mature learners at a variety of levels of proficiency. The article then presents an orderly, four-step approach to any literary text, an approach that obliges students to take responsibility for building their own successively more complex schemata (i.e., levels of understanding), which allow them to explore a text on successively more demanding levels. The theoretical approach is illustrated with reference to Hemingway's short story "Soldier's Home." Almost a decade after Canale and Swain's (1980) seminal article, the concept of communicative competence has found its expression in a wide variety of attitudes and concerns about the active role of the communicating learner in the second language classroom. Disappointingly (a few excellent articles notwithstanding-e.g., McConochie, 1985; Povey, 1979a; Spack, 1985; Widdowson, 1982), literary texts, which have the potential to provide the basis for intensely interactive, content-based ESL classes, have not enjoyed the general resurgence of attention that our commitment to communicative teaching might have predicted. It has been my personal experience that many ESL teachers either consciously or unconsciously feel that "literature is too 'hard' for ESL students." Given the large number of language-teaching

Creating Socially Supportive Environments for Fully Included Students who Experience Multiple Disabilities

Abstract: This investigation analyzed the effectiveness of an intervention designed to facilitate the social inclusion of three students who experienced significant physical and intellectual challenges and, ...

Lightning flashes conducive to the production and escape of gamma radiation to space

Abstract: [1] Gamma radiation observed in space has been associated with lightning flashes in thunderstorms. These special flashes do not appear to be the large and energetic positive ground flashes that also produce sprites. Considerations of gamma ray attenuation in air indicate that such flashes may not produce gamma radiation at sufficient altitude to enable their escape to space. High-altitude intracloud lightning, most prevalent in the tropics where the tropopause is also high, may be a necessary source.