Washington State University

About: Washington State University is a education organization based out in Pullman, Washington, United States. It is known for research contribution in the topics: Population & Gene. The organization has 26947 authors who have published 57736 publications receiving 2341509 citations. The organization is also known as: WSU & Wazzu.

Winter cover crop effects on soil organic carbon and carbohydrate in soil

Abstract: Winter cover crops may increase soil organic carbon (SOC) levels or reduce their rate of depletion. Selection of appropriate cover crops to increase SOC requires an adequate knowledge of the quality and quantity of plant biomass produced and its rate of decomposition in soil. This study examined the SOC and carbohydrate concentrations in soil as affected by several leguminous and nonleguminous cover crops after 6 yr of a corn (Zea mays L.) cover crop double cropping system in a temperate, humid region. The vegetation in the control treatment without cover crops was primarily shepherd's-purse [Capsella bursa-pastoris (L.) Medikus]. The cover crops had a variable effect on SOC and soil carbohydrate concentrations due to a significant difference in total organic C and carbohydrate produced by the cover crops. The buried bag technique showed that the biomass C from the aboveground biomass of the cover crops decomposed rapidly in the soil with a half-life averaging 30.9 ± 9.4 (SD) d in 1992 and 55.2 ± 7.8 (SD) d in 1993. The decomposition of carbohydrate in the aboveground biomass in the soil was also rapid with an average half-life of 40.0 ± 13.1 (SD) d in 1992 and 50.5 ± 11.8 (SD) d in 1993. The overriding cover crop effect on SOC and carbohydrate was due to the magnitude of the C inputs from the cover crops. With more than 4 Mg ha -1 of top biomass, cereal rye (Secale cereale L.) and annual ryegrass (Lolium multijlorum Lam.) were better suited as winter cover crops for building SOC levels in this region than Austrian winter pea (Lathyrus hirsutus L.), hairy vetch (Vicia villosa Roth), and canola (Brassica napus L.).

ERM is required for transcriptional control of the spermatogonial stem cell niche

Abstract: Division of spermatogonial stem cells1 produces daughter cells that either maintain their stem cell identity or undergo differentiation to form mature sperm. The Sertoli cell, the only somatic cell within seminiferous tubules, provides the stem cell niche through physical support and expression of surface proteins and soluble factors2,3. Here we show that the Ets related molecule4 (ERM) is expressed exclusively within Sertoli cells in the testis and is required for spermatogonial stem cell self-renewal. Mice with targeted disruption of ERM have a loss of maintenance of spermatogonial stem cell self-renewal without a block in normal spermatogenic differentiation and thus have progressive germ-cell depletion and a Sertoli-cell-only syndrome. Microarray analysis of primary Sertoli cells from ERM-deficient mice showed alterations in secreted factors known to regulate the haematopoietic stem cell niche. These results identify a new function for the Ets family transcription factors in spermatogenesis and provide an example of transcriptional control of a vertebrate stem cell niche.

The Effects of Emotional Arousal and Valence on Television Viewers' Cognitive Capacity and Memory.

Abstract: This study examines the combined effects of arousal and valence on viewers’ capacity allocation to and memory for television messages. Results show that when valence (how positive or negative a message is) is controlled, arousing messages are remembered better than calm messages. When arousal is controlled, positive messages are remembered better than negative messages. Reaction time results suggest that capacity allocation is a function of both valence and arousal. Viewers allocate the most capacity to positive arousing messages and the least capacity to negative arousing messages. The calm messages (both positive and negative) fall between these two.