Night Moment and Spring

Poems include: Night Moment , by Robert Schalk and Spring , by Wyoming Robinso

Activity Level-Predation Risk Tradeoff in a Tadpole Guild: Implications for Community Organization Along the Hydroperiod Gradient

Increasing activity levels permit greater food intake for use towards growth and reproduction, consequently increasing predation risk via increased detection. Larval anurans are models to examine activity level-predation risk tradeoffs, as they occupy a variety of lentic habitats that impose constraints on the distribution and abundance of species. Ephemeral ponds have a low abundance and diversity of predators and as a result tadpole species tend to have high foraging rates for rapid development. Permanent ponds generally possess a greater diversity and abundance of predators and tadpoles inhabiting these locations tend to have low activity rates or chemical defenses to minimize predation risk. The objective of this research was to examine how interspecific variation in activity level and response to predation risk, corresponds to the distributions of tadpole species along the hydroperiod gradient. Furthermore, we examined the intraspecific variation in activity level among the species. We conducted a series of laboratory experiments in which we quantified baseline activity patterns and the change in activity after the addition of a predator or exposure to alarm cues, for 12 species of larval anurans native to East Texas. Species that maintained a high activity level generally occupied ephemeral ponds and species that maintained low activity levels generally occupied permanent ponds. Only one species (Gastrophryne carolinensis) decreased their activity level in the presence of predator cues or conspecific alarm cues. These results highlight this tradeoff can have consequences on the life histories of multiple species, providing insight into how it affects the organization of ecological communities

The Sketcher: Reverend John Eagles, His Poetical Shelter from the World and the 1812 Collection

...Since identifying Eagles as at least one of the artists of the 1812 Collection, I have discovered that his specific tour of the Lakes, the route he followed and the scenery conveyed in his images, deviated from the conventional tours in that Eagles was in search of what he regarded as a poetical landscape rather than a traditionally picturesque one. In other words, Eagles sought to capture more than an aesthetically pleasing scene as a picturesque image would, he endeavored to capture the soul of the scene and the 1812 Collection is evidence that Eagles practiced the artistic principles he so often espoused. As such, the 1812 Collection offers further implications for Eagles\u27s body of work, his aesthetic, and his strong criticisms of the changes he witnessed in landscape art during his lifetime. In this essay, I therefore propose demonstrate not only how the 1812 Collection is in critical conversation with the picturesque tradition, but also how Eagles\u27s sketches, like his writings and criticisms, expressed his own guiding aesthetic on discovering the poetry of nature instead of a strictly picturesque aesthetic. In doing so, I hope to restore Eagles\u27s reputation as an artist and art critic as well as reveal the historical importance of the recently rediscovered 1812 Collection

Nonuniform high-gamma (60-500 Hz) power changes dissociate cognitive task and anatomy in human cortex

High-gamma-band (\u3e60 Hz) power changes in cortical electrophysiology are a reliable indicator of focal, event-related cortical activity. Despite discoveries of oscillatory subthreshold and synchronous suprathreshold activity at the cellular level, there is an increasingly popular view that high-gamma-band amplitude changes recorded from cellular ensembles are the result of asynchronous firing activity that yields wideband and uniform power increases. Others have demonstrated independence of power changes in the low- and high-gamma bands, but to date, no studies have shown evidence of any such independence above 60 Hz. Based on nonuniformities in time-frequency analyses of electrocorticographic (ECoG) signals, we hypothesized that induced high-gamma-band (60-500 Hz) power changes are more heterogeneous than currently understood. Using single-word repetition tasks in six human subjects, we showed that functional responsiveness of different ECoG high-gamma sub-bands can discriminate cognitive task (e.g., hearing, reading, speaking) and cortical locations. Power changes in these sub-bands of the high-gamma range are consistently present within single trials and have statistically different time courses within the trial structure. Moreover, when consolidated across all subjects within three task-relevant anatomic regions (sensorimotor, Broca\u27s area, and superior temporal gyrus), these behavior- and location-dependent power changes evidenced nonuniform trends across the population. Together, the independence and nonuniformity of power changes across a broad range of frequencies suggest that a new approach to evaluating high-gamma-band cortical activity is necessary. These findings show that in addition to time and location, frequency is another fundamental dimension of high-gamma dynamics

The swing adsorption reactor cluster for post-combustion CO2 capture from cement plants

The swing adsorption reactor cluster is a promising new method for post-combustion CO2 capture using a synergistic combination of temperature and pressure swings. The pressure swing is carried out by a vacuum pump and allows for 90% CO2 capture using only a small temperature swing, which is carried out by a heat pump. The small temperature swing allows the heat pump to transfer heat from carbonation to regeneration at a very high efficiency, minimizing the energy penalty. When applied to a cement plant, the energy penalty reduces further relative to a coal power plant that has a lower CO2 content in the flue gas. Higher CO2 concentrations allow a given CO2 capture ratio to be achieved with a smaller temperature swing, thus further improving the heat pump efficiency. As a result of the high heat pump efficiency and of the limited amount of waste heat available, heat integration with the cement plant yielded negligible efficiency gains. A swing adsorption reactor cluster post-combustion CO2 capture facility can therefore be constructed independently from the cement plant, making it attractive for retrofits. The specific energy consumption for CO2 avoidance of the process was determined as 2.04 MJLHV/kgCO2 when using electricity from the average European power mix, which is lower than all competing technologies recently assessed in the literature aside from oxyfuel CO2 capture. Primary energy consumption will continue to decline as the electricity sector decarbonizes, increasing the attractiveness of the swing adsorption reactor cluster over coming decades.publishedVersio

Economic assessment of the swing adsorption reactor cluster for CO2 capture from cement production

Cement production is responsible for about 8% of global CO2 emissions. Most of these emissions originate from the process itself and thus cannot be avoided via clean energy, leaving CO2 capture as the only viable solution. This study investigates the prospects of decarbonizing the cement industry via the swing adsorption reactor cluster (SARC) – a new post-combustion CO2 capture technology that requires no integration with the host process, consumes only electrical energy and shows a competitive energy penalty. SARC operates by synergistically combining a temperature swing using a heat pump and a vacuum swing using a vacuum pump. In the present study, the SARC concept is evaluated economically and compared to several benchmarks. SARC achieves CO2 avoidance costs of €52/ton in the base case, which is higher than oxyfuel combustion, similar to calcium looping and lower than four other technology options. SARC can approach the cost of oxyfuel combustion with more optimistic assumptions regarding economies of scale, particularly for the vacuum pump. The local electricity mix is another important factor because SARC, as an electricity consumer, becomes more attractive when the price and CO2 intensity of electricity is low. Furthermore, the simplicity of retrofitting existing cement plants with the SARC process becomes increasingly valuable when rapid CO2 emissions reductions are targeted. SARC is therefore well positioned for a global decarbonization effort aiming to limit global warming well below 2 °C.publishedVersio

Assessment of Biosignals for Managing a Virtual Keyboard

In this paper we propose an assessment of biosignals for handling an application based on virtual keyboard and automatic scanning. The aim of this work is to measure the effect of using such application, through different interfaces based on electromyography and electrooculography, on cardiac and electrodermal activities. Five people without disabilities have been tested. Each subject wrote twice the same text using an electromyography interface in first test and electrooculography in the second one. Each test was divided into four parts: instruction, initial relax, writing and final relax. The results of the tests show important differences in the electrocardiogram and electrodermal activity among the parts of tests.Junta de Andalucía p08-TIC-363

The behaviour of a reinforced soil mattress spanning a cavity modelled in a geotechnical centrifuge

Sinkholes can occur on land underlain by dolomite and cause substantial damage to buildings and even loss of life. More than four million people work or reside on dolomite land in South Africa and it is therefore important to be able to construct safely on dolomite land and to minimise the risk of damage to infrastructure and loss of life. Compacted soil mattresses are often used to found structures on areas underlain by dolomite. This study investigated the effect of tensile reinforcement on the behaviour of a soil mattress spanning an underlying water filled cavity designed to impose a cover subsidence sinkhole. Three small-scale models, each consisting of a soil mattress with a cover subsidence sinkhole forming underneath, were constructed and tested in a geotechnical centrifuge. In the first test, an unreinforced soil mattress was tested and in two more tests, reinforced soil mattresses with different reinforcement strengths were tested. The settlement of the unreinforced soil mattress was initially less than that of the reinforced soil mattresses up to the point at which it failed suddenly. Neither of the reinforced soil mattresses failed suddenly, but both experienced large surface settlements that would have led to substantial damage to an overhead structure.http://link.springer.com/journal/107062017-10-30hb2016Civil Engineerin