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The effect of protons on E2V technologies L3Vision CCDs
The effect of different 10 MeV equivalent proton fluences on the performance of E2V Technologies (formerly Marconi applied technologies, formerly EEV) L3Vision Charge Coupled Devices (CCDs) was investigated. The first experimental radiation damage results of the L3Vision device are presented, with emphasis given to the analysis of damage to the gain register of the device. Changes in dark current and generation of bright pixels in the CCD image, store, readout register and gain register as a result of proton irradiation are reported and viewed in light of the potential use of the device in space-based applications
Proton induced leakage current in CCDs
The effect of different proton fluences on the performance of two E2V Technologies CCD47-20 devices was investigated with particular emphasis given to the analysis of 'random telegraph signal' (RTS) generation, bright pixel generation and induced changes in base dark current level. The results show that bright pixel frequency increases as the mean energy of the proton beam is increased, and that the base dark current level after irradiation scales with the level of ionization damage. For the RTS study, 500 pixels on one device were monitored over a twelve hour period. This data set revealed a number of distinct types of pixel change level fluctuation and a system of classification has been devised. Previously published RTS data is discussed and reviewed in light of the new data
Steady heartbeat: Field and laboratory studies indicate unexpected resilience to high temperatures for the ribbed mussel Geukensia demissa
Salt marshes are important ecosystems found along the coast of Georgia. Salt marshes are hosts to diverse organisms that interact with each other to promote many ecosystem services, such as storm buffering and flooding, and absorption of excess nutrients. Among these diverse organisms is the ribbed mussel, Geukensia demissa. Mussels are a foundation species in this intertidal landscape, and without them the whole salt marsh would be negatively affected. The purpose of this investigation was to explore the thermal stress response of G. demissa to rising temperatures. Mussels were collected from three locations that were landlocked, close to a road, and far away from a road on Tybee Island, Georgia. The presence of this road has greatly increased the temperature in the salt marsh. Thus, we hypothesize that mussels will have an increased heart rate with increased temperature. To test this hypothesis, the heartbeat of G. demissawere recorded using an IR sensor in laboratory and field experiments at reduced and elevated temperatures. Results showed that mussels from locations regularly experiencing elevated temperatures do not have an increased heart rate. However, mussels from locations that experience lower temperatures did. These results indicate that mussels are more resilient to higher temperatures than previously expected. This study is significant for marsh conservationists and scientists wishing to preserve and maintain the salt marsh and its ecosystem services
Steady heartbeat: Field and laboratory studies indicate unexpected resilience to high temperatures for the ribbed mussel Geukensia demissa
Salt marshes are important ecosystems found along the coast of Georgia. Salt marshes are hosts to diverse organisms that interact with each other to promote many ecosystem services, such as storm buffering and flooding, and absorption of excess nutrients. Among these diverse organisms is the ribbed mussel, Geukensia demissa. Mussels are a foundation species in this intertidal landscape, and without them the whole salt marsh would be negatively affected. The purpose of this investigation was to explore the thermal stress response of G. demissato rising temperatures. Mussels were collected from three locations that were landlocked, close to a road, and far away from a road on Tybee Island, Georgia. The presence of this road has greatly increased the temperature in the salt marsh. Thus, we hypothesize that mussels will have an increased heart rate with increased temperature. To test this hypothesis, the heartbeat of G. demissawere recorded using an IR sensor in laboratory and field experiments at reduced and elevated temperatures. Results showed that mussels from locations regularly experiencing elevated temperatures do not have an increased heart rate. However, mussels from locations that experience lower temperatures did. These results indicate that mussels are more resilient to higher temperatures than previously expected. This study is significant for marsh conservationists and scientists wishing to preserve and maintain the salt marsh, its ecosystem services
Transitioning to a Master\u27s Degree Granting University: Implications for Librarian Instruction, Outreach, and Collection Development
Athens State University is located in Athens, Alabama in the northern part of Alabama bordering Giles County, Tennessee. It is one of the only upper-level universities serving juniors, seniors, and graduate students in the country. The student body consists primarily of non-traditional and first-generation students. In 2014, Athens State University was approved to offer a graduate program in Global Logistics and Supply Chain Management in the College of Business by the Alabama Commission on Higher Education (ACHE). Since then, Athens State University has expanded its graduate offerings to include five additional fields of study: Strategic Healthcare Management and Administration, Strategic Human Resource Management, Strategic Leadership and Business Analytics, Religious Studies, and Career and Technical Education. Currently, more graduate degrees are in the development stages in all three colleges: Business, Arts and Sciences, and Education. All of the graduate programs are delivered asynchronously online with some classes having additional synchronous components.
How have library instruction, outreach, and collection development evolved to meet the needs of the graduate student population? How do librarians best serve graduate students in a strictly online environment? How do librarians promote active learning techniques such as providing micro-lectures, including welcome and orientation videos, planning effective discussions with prompts, and increasing motivation in an online environment? What are some effective and reflective techniques and tools to promote inclusivity such as signaling ally-ship and assessing online learning objects for accessibility and ADA compliance?
Athens State University librarians hold faculty status and serve both undergraduate and graduate students as subject liaisons. This presentation will share the librariansâ experiences of transitioning from a library serving exclusively undergraduates to one serving both undergraduate and graduate students. Given that the programs are offered solely online, librarians will also discuss the challenges and successes encountered along the way. Future areas of discussion include quantitative and qualitative assessment plans. Participant takeaways include the following: Adjusting collection assessment for budget allocation Adapting collection development for graduate programs Building working relationships with graduate teaching faculty Providing support to graduate students in an online environment Promoting inclusivity and accessibilit
An Evaluation of the Efficacy of Selected Nonpharmacologic Pain Interventions in Infants
Infants subjected to painful stimuli respond with deleterious physiologic and metabolic effects, behavioral changes, and potentially long term effects on painful stimuli processing and response. There are few studies that address effective pain interventions for infants, particularly those interventions that staff nurses can implement independently. Interventions must be identified and their effectiveness must be validated for this vulnerable population. Pharmacologic management of pain may cause deleterious side effects and needs to be ordered by physicians or nurse practitioners. Nonpharmacologic methods to manage pain can usually be implemented by staff nurses independently. This study evaluated the efficacy of two nonpharmacologic pain management interventions, sucking and sucrose, and their ability to potentiate each other. This study is based on the Gate Control Theory of pain which posits that benign stimuli, such as sucking, send messages to the central nervous system that compete with painful stimuli to decrease the amount of pain perceived. Sucrose is thought to be mediated through opioid pathways. A sucrose coated pacifier may reduce pain via two pathways, thus being more effective than uni-modal techniques. A randomized, complete block, experimental design was used to evaluate the pain reduction efficacy of a: sucrose coated pacifier, oral sucrose solution, water moistened pacifier, and no intervention. Eighty-four neonates undergoing the painful procedure of heelstick were studied. Pain measures were duration of cry, vagal tone, and salivary cortisol. MANOVA revealed that the sucrose coated pacifier group cried significantly less than the water moistened pacifier and control groups. ANCOVA demonstrated significant covariation of birth weight with cortisol and procedure length with cry, neither covariate impacted treatment main effects. Repeated measures ANOVA revealed that the sucrose coated pacifier group demonstrated significantly lower vagal tone during heelstick than did the oral sucrose solution and no intervention groups. This significant difference persisted for 15 minutes post heelstick between the sucrose coated pacifier and no intervention groups. In summary, this study demonstrated the clinical efficacy of offering a sucrose coated pacifier to manage pain during heelstick in healthy neonates
Decadal Evolution of Ocean Thermal Anomalies in the North Atlantic: The Effects of Ekman, Overturning, and Horizontal Transport
Basin-scale thermal anomalies in the North Atlantic, extending to depths of 1â2 km, are more pronounced than the background warming over the last 60 years. A dynamical analysis based on reanalyses of historical data from 1965 to 2000 suggests that these thermal anomalies are formed by ocean heat convergences, augmented by the poorly known airâsea fluxes. The heat convergence is separated into contributions from the horizontal circulation and the meridional overturning circulation (MOC), the latter further separated into Ekman and MOC transport minus Ekman transport (MOC-Ekman) cells. The subtropical thermal anomalies are mainly controlled by wind-induced changes in the Ekman heat convergence, while the subpolar thermal anomalies are controlled by the MOC-Ekman heat convergence; the horizontal heat convergence is generally weaker, only becoming significant within the subpolar gyre. These thermal anomalies often have an opposing sign between the subtropical and subpolar gyres, associated with opposing changes in the meridional volume transport driving the Ekman and MOC-Ekman heat convergences. These changes in gyre-scale convergences in heat transport are probably induced by the winds, as they correlate with the zonal wind stress at gyre boundaries
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