4,711 research outputs found
Simultaneous Encoding of Odors by Channels with Diverse Sensitivity to Inhibition
Odorant receptors in the periphery map precisely onto olfactory glomeruli (“coding channels”) in the brain. However, the odor tuning of a glomerulus is not strongly correlated with its spatial position. This raises the question of whether lateral inhibition between glomeruli is specific or nonspecific. Here we show that, in the Drosophila brain, focal activation of even a single glomerulus recruits GABAergic interneurons in all glomeruli. Moreover, the relative level of interneuron activity in different glomeruli is largely odor invariant. Although interneurons are recruited nonspecifically, glomeruli differ dramatically in their sensitivity to interneuron activity, and this is explained by their varying sensitivity to GABA. Interestingly, a stimulus is typically encoded in parallel by channels having high and low sensitivity to inhibition. Because lateral inhibition confers both costs and benefits, the brain might rely preferentially on “high” and “low” channels in different behavioral contexts
A Silvan Tomkins Handbook
An accessible guide to the work of American psychologist and affect theorist Silvan Tomkins The brilliant and complex theories of psychologist Silvan Tomkins (1911–1991) have inspired the turn to affect in the humanities, social sciences, and elsewhere. Nevertheless, these theories are not well understood. A Silvan Tomkins Handbook makes his theories portable across a range of interdisciplinary contexts and accessible to a wide variety of contemporary scholars and students of affect. A Silvan Tomkins Handbook provides readers with a clear outline of Tomkins’s affect theory as he developed it in his four-volume masterwork Affect Imagery Consciousness. It shows how his key terms and conceptual innovations can be used to build robust frameworks for theorizing affect and emotion. In addition to clarifying his affect theory, the Handbook emphasizes Tomkins’s other significant contributions, from his broad theories of imagery and consciousness to more focused concepts of scenes and scripts. With their extensive experience engaging and teaching Tomkins’s work, Adam J. Frank and Elizabeth A. Wilson provide a user-friendly guide for readers who want to know more about the foundations of affect studies
MITOCHONDRIAL CHANGES IN THE LIVER OF ESSENTIAL FATTY ACID-DEFICIENT MICE
Livers of mice on diets deficient in essential fatty acids (EFA) have been studied by light and electron microscopy. The most conspicuous changes occur in the mitochondria. In light microscopy the mitochondria appear very much enlarged in the periportal region of the lobule. In electron micrographs they have additional cristae, sometimes very abundant. ranged in stacks in the central cavity. The matrix may be more electron-opaque than normal. This is in contrast with the enlarged mitochondria appearing under other experimental conditions, where the cristae are reduced in number and the matrix is less electron-opaque. It is known that there is an uncoupling of oxidative phosphorylation in EFA-deficient mitochondria. As a hypothesis it is proposed that the uncoupling may be due to a molecular defect caused by the absence of EFA in the structure that determines the spatial relationship between the electron transport chain and oxidative phosphorylation. It is further tentatively suggested that the changes in mitochondria may be attributed to lack of ATP. The possibility is discussed that the mitochondrial changes are ineffective attempts at compensation for this lack
Going rogue: what scientists can learn about Twitter communication from “alt” government accounts
The inauguration of President Trump in the United States led to the active restriction of science communication from federal agencies, resulting in the creation of many unofficial “alt” Twitter accounts to maintain communication. Alt accounts had many followers (e.g., 15 accounts had \u3e 100,000) and received a large amount of media attention, making them ideal for better understanding how differences in messaging can affect public engagement with science on microblogging platforms. We analyzed tweets produced by alt and corresponding official agency accounts to compare the two groups and determine if specific features of a tweet made them more likely to be retweeted or liked to help the average scientist potentially reach a broader audience on Twitter. We found adding links, images, hashtags, and mentions, as well as expressing angry and annoying sentiments all increased retweets and likes. Evidence-based terms such as “peer-review” had high retweet rates but linking directly to peer-reviewed publications decreased attention compared to popular science websites. Word choice and attention did not reflect official or alt account types, indicating topic is more important than source. The number of tweets generated and attention received by alt accounts has decreased since their creation, demonstrating the importance of timeliness in science communication on social media. Together our results show potential pathways for scientists to increase efficacy in Twitter communications
Carbon Capture and Sequestration: Identifying and Managing Risks
Carbon capture and geologic sequestration (CCS) technology promises to provide deep emissions cuts, particularly from coal power generation, but deploying CCS creates risks of its own. This article first considers the risks associated with CCS, which involves capturing CO{sub 2} emissions from industrial sources and power plants, transporting the CO{sub 2} by pipeline, and injecting it underground for permanent sequestration. The article then suggests ways in which these risks can be minimized and managed and considers more broadly when or if CCS should be deployed or whether its use should be limited or rejected in favor of other solutions
Energy Consumption Data: The Key to Improved Energy Efficiency
This Article explores recent efforts that federal, state, and local governments have taken to create regulatory frameworks to collect energy consumption data and make it available to consumers and, in some cases, to the public. Part II explains the nature of energy consumption data, the problems with not having such data readily available to consumers and policymakers, and the benefits associated with making it available to a wider range of potential users. Part III explores developing federal, state, and local policies governing energy consumption data, including how policymakers have attempted to address some of the privacy and other concerns associated with such data. Part IV evaluates these efforts and attempts to provide guidance to policymakers on how to develop more robust regulatory frameworks to help capitalize on the potential energy efficiency benefits associated with increased collection, evaluation, and disclosure of energy consumption data
An expert system for configuring a network for a Milstar terminal
This paper describes a rule-based expert system which assists the user in configuring a network for Air Force terminals using the Milstar satellite system. The network configuration expert system approach uses CLIPS. The complexity of network configuration is discussed, and the methods used to model it are described
OPTIMAL CRANK ARM LENGTH AND BODY POSITION FOR ROAD SPRINT CYCLING PERFORMANCE
The purpose of the current study was to examine the effects of body position and crank arm length (CAL) on power production in road sprint cycling. Six well trained male cyclists were tested in the standing and seated positions, and with three CALs of 18, 20 and 22 % of leg length whilst out of the saddle. A modified six second Wingate test on a Velotron ergometer was used to measure power (Watts) and cadence (rpm), and a Vicon MX system was used to measure the hip and lower limb kinematics of the pedal cycle. A 4% increase in power was observed when riding out of the saddle and a CAL set at 18- 20% of leg length was superior for this task. The coordination pattern employed was consistent between postures and with different CALs
Merging Nitrogen Management and Renewable Energy Needs
The ARBRE (ARable Biomass Renewable Energy) project, the first large-scale wood-fueled electricity generating plant in the U.K., represents a significant development in realising British and European policy objectives on renewable energy. The plant is fueled by a mix of wood from short rotation coppice (SRC) and forest residues. Where feasible, composted/conditioned sewage sludge is applied to coppice sites to increase yields and improve soil structure. In the Yorkshire Water region, typical total N:P:K composition of composted/conditioned sludge is 2.9:3.8:0.3, respectively. Sludge application is calculated on the basis of total nitrogen (N) content to achieve 750 kg N ha-1, for 3 years’ requirement. Willow coppice forms a dense, widely spaced, root network, which, with its long growing season, makes it an effective user of nutrients. This, in combination with willow’s use as a nonfood, nonfodder crop, makes it an attractive route for the recycling of sewage sludge in the absence of sea disposal, banned under the EC Urban Waste Water Treatment Directive (UWWTD). Further work is required on the nutritional requirements of SRC in order to understand better the quantities of sludge that can be applied to SRC without having a detrimental impact on the environment. This paper suggests the source of N rerouting under the UWWTD and suggests the likely expansion of SRC as an alternative recycling pathway
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