Integrating emerging trends in upstream process development: Autosampling, nutrient feedback control, and single use tanks

Key to effective upstream development is the presence of resource-efficient systems for examining complex process options. In this presentation, we report the design and characterization of a 3-L rigid single-use bioreactor (SUB), combined with a completely automated sampling and control system capable of evaluating different metabolic-based feed strategies. Considerations in our development of a custom 3-L SUB, targeted to replace current workhorse glass reactors, encompassed proper technical functionality to flexibility and ease of use. Highlights include: vessel configuration details (impeller, sparger, baffles), perfusion readiness, agitation system design (magnetic bottom drive), and extra sensor ports and feed lines. The SUB was developed through multiple iterations to arrive at the final design, which was characterized experimentally for kLa and by CFD for mixing. The final engineering design is able to support cell density above 100x106 cells/mL. In parallel we pursued an automated system capable of investigating feed strategies tailored to real-time cell metabolite measurements, i.e. with feedback control based upon residual metabolite levels. In the end our customized automated sampling and feed control system allows programmed sampling of both cell-free and cell-containing retains from eight bioreactors, delivery to integrated analyzers, and control of nutrient feed pumps (2 per bioreactor). The system is capable of feedback control to implement individualized feed strategies that incorporate data inputs from the integrated analyzers. Implementation of the custom 3-L SUBs and automated sampling and feed control system has enabled enhanced process development capability, by introducing technology to both improve operational efficiency and facilitate experiments of greater complexit

Vacuum Ignition Characteristics of Oxygen Difluoride/diborane and Flox/diborane Final Report, 15 Jan. - 14 Dec. 1969

Vacuum ignition characteristics of oxygen difluoride diborane and FLOX diboran

Electronic Theses and Dissertations: Two Surveys of Editors and Publishers

In two separate surveys, editors and publishers of established academic journals were invited to respond to online questions exploring issues surrounding prior publication in an electronic environment, with particular emphasis on electronic theses and dissertations (ETDs), With response rates of27% and 58% respectively, certain conclusions and patterns could be discerned. The most noticeable pattern was a lack of consensus on the question of electronic dissemination and how it mayor may not contribute to the designation of research as published . The differences in opinion are varied and will be presented in both statistical and narrative format, with results from both surveys being presented

Efficacy of an Acoustic Hailing Device as an Avian Dispersal Tool

Bird strikes are a major safety and financial concern for modern aviation. Audible stimuli are common bird dispersal techniques, but their effectiveness is limited by the saliency and relevance of the stimulus. Furthermore, high ambient sound levels present at airfields might require that effective audible stimuli rely more on total volume (i.e., exceeding physiological tolerances) than ecological relevance. Acoustic hailing devices (AHD) are capable of sound output with a narrow beamwidth and at volumes high enough to cause physical discomfort at long distances. We tested the effectiveness of anAHD as a dispersal tool on freeranging birds recognized as hazardous to aviation safety at the Savannah River Site and Phinizy Swamp Nature Park in South Carolina and Georgia, USA, respectively, between October 2013 and March 2015. Our study design included experimental trials with timed-interval counts of birds directly before and after AHD treatment. For most species, counts of birds associated with treatment periods (use of AHD) and control periods (no use of AHD) occurred on different days. Sound treatments yielded variable success at dispersing birds. Specifically, AHD treatment was effective for dispersing vultures (Coragyps atratus and Cathartes aura) and gulls (Laridae), but ineffective for dispersing blackbirds (Icteridae), diving ducks (Aythya spp., Bucephala spp., Oxyura spp.), and coots (Fulica americana). Trials were conducted in a relatively quiet environment with birds that were unhabituated to excessive noise; thus, we cannot unequivocally recommend an AHD as a universally effective avian dispersing tool. However, future research should consider AHD testing integrated with other methods, as well as investigation of treatments that might be salient to specific target species

Report to the Chicago Park District on Conflicts with Ring-billed Gulls and the 2013 Integrated Ring-billed Gull Damage Management Project

The large ring-billed gull (Larus delawarensis) population in the City of Chicago has caused various conflicts including general nuisance, property damage, economic losses, and threats to human health and safety. Several studies have shown a relationship between ring-billed gulls and increased levels of fecal indicator bacteria (FIB) such as Escherichia coli (E. coli) in nearshore waters. Results of tests for E. coli have led to the issuance of swim advisories at Chicago beaches. The objectives of the Chicago Ring-billed Gull Damage Management Project were to (1) reduce the local production of ring-billed gulls, (2) reduce the severity of conflicts with gulls including the issuance of swim advisories, and (3) evaluate how limiting the production of gulls affects gull use of Chicago’s beaches. Since the beginning of the Chicago Ring-billed Gull Damage Management Project in 2007, USDA-WS established that oiling eggs with food-grade corn oil was a successful method in reducing gull production. Between 2007 and 2013, 89,278 ring-billed gull nests were rendered inviable. It is estimated that between 71,422 and 169,628 hatch-year ring-billed gulls have been prevented since the initiation of this project. Management of ring-billed gull nests has contributed to a significant reduction in hatch-year gull use of Chicago beaches. Since 2007, hatch-year gull use of beaches has declined by 85%, with all analyzed beaches showing a significant reduction. The combined observations of hatch-year and after hatch-year gull use of beaches illustrated a reduction in gulls compared to 2007 observation totals. Conflicts with landowners and land managers have been reduced as a result of our efforts to limit production of young gulls. The connection between ring-billed gulls and water quality is becoming more evident. It has been demonstrated that a relationship exists between gulls and the concentration of E. coli at beaches. During our seven treatment years and the prior (pretreatment) year, the Chicago Park District has routinely sampled for E. coli as a FIB to assess water quality. During the 2013 swim season the proportion of tests resulting in a swim advisory compared to 2006 (baseline year) declined at 13 of 14 beaches

Investigations into Earthworm Control on Airports

Earthworms, though generally considered beneficial for soil conditioning, can become a hazard at airports. When found in large numbers on runways or taxiways after heavy rainfall, they create slippery conditions for aircraft rolling over them. Additionally, earthworms attract birds, especially gulls, thereby increasing the risk of bird strikes to aircraft that are landing or taking off. For example, during a 35-minute period on 3 September 2004 at Calgary International Airport (YYC), a B737 of Westjet and an A319 of Air Canada aborted takeoffs after multiple strikes with gulls attracted to the runways to feed on earthworms. The B737 had strikes and damage to both engines and the A319 had damage (apparently an uncontained failure) to one engine. In the Netherlands, they build concrete moats to keep worms off of runways. There are no pesticides registered for earthworm control. Consequently any application of a pesticide to kill worms would be illegal. Researchers in England, Oregon, and Washington found that incorporating abrasive material into soil reduced the number of worms coming to the surface. We are conducting trials at the USDA\u27s National Wildlife Research Center Ohio Field Station to develop simple procedures to reduce earthworm numbers on runways and taxiways. In lab trials, night crawlers (Lumbricus terrestris) have been initially repelled from areas containing phosphate fertilizer, high nitrate fertilizer or a mustard byproduct. Ground mustard mixed with diatomaceous earth also shows promise in reducing the number of earthworms in treated plots. Additionally, when placed on recycled coal slag, the worms have not burrowed into the material but tried to leave the test site. We anticipate field trials to investigate an integrated approach involving products that present both chemical and physical irritants. If a successful combination of products is determined, the number of earthworms crawling onto taxiways and runways could be significantly reduced

Can experience reduce collisions between birds and vehicles?

Bird collisions with vehicles cause serious safety, financial and conservation concerns worldwide, but the causes of such collisions are poorly described. We investigated how experience with vehicles influenced avian avoidance responses. We trained three groups of vehicle-naiıve rock pigeons Columba livia with 32 near-miss vehicle approaches over 4 weeks at 60 and 120 km h-1, and also included individuals that heard but did not see the approaches (control group). We subsequently measured flight initiation distance (FID) and whether individuals ‘collided’ with a virtual vehicle directly approaching at 120 or 240 km h-1 using video playback. We found that inexperienced individuals (i.e. the control group) had longer FIDs than experienced birds, although only one of 90 individuals across groups successfully avoided virtual collision. Vehicle approach speed during video playback and the interaction of approach speed and training group did not influence FID. Our results suggest that a habituation-like effect based on repeated observations of passing vehicles could contribute to ineffective vehicle avoidance responses by birds when collisions are imminent. Novel strategies should be developed to enhance avoidance responses to high-speed vehicles to minimize bird mortality

Individual variation in avian avoidance behaviours in response to repeated, simulated vehicle approach

Birds exhibit variation in alert and flight behaviours in response to vehicles within and between species, but it is unclear how properties inherent to individuals influence variation in avoidance responses over time. We examined individual variation in avoidance behaviours of Brown-headed Cowbirds (Molothrus ater (Boddaert, 1783)) in response to repeated presentation of a simulated vehicle approach in a video playback scenario. Wemodeled temporal alert and flight behaviours to determine whether overall behavioural variation resulted primarily from variation within individuals (i.e., intraindividual variation) or between individuals (i.e., interindividual variation). We examined reaction norms (individual × treatment day) and whether birds showed plasticity in responses via habituation or sensitization. Repeatability in the response metrics for individuals was low (~0.22 for alert and flight), indicating that model variation was due primarily to within-individual variation rather than between-individual variation. We observed sensitization in alert responses over time, but no sensitization or habituation in flight responses. Our results indicate that individuals learned to anticipate the vehicle approach but did not vary their escape behaviour, suggesting that alert and flight behaviours might be affected differently by cues associated with oncoming objects or experience with them. We consider our findings in light of the ongoing development of strategies to reduce animal–vehicle collisions. Si les oiseaux présentent des variations intraspécifiques et interspécifiques des comportements d’alerte et de fuite en réaction aux véhicules, l’influence des propriétés individuelles sur les variations des réactions d’évitement avec le temps n’est pas bien établie. Nous avons examiné les variations individuelles des comportements d’évitement de vachers à tête brune (Molothrus ater (Boddaert, 1783)) en réponse à la présentation répétée d’une approche de véhicule simulée dans un scénario de reprise vidéo. Nous avons modélisé les comportements d’alerte et de fuite dans le temps afin de déterminer si les variations comportementales globales résultaient principalement de variations intraindividuelles ou interindividuelles. Nous avons examiné les normes de réaction (individu × jour du traitement) et si les réactions des oiseaux présentaient une plasticité sous forme d’accoutumance ou de sensibilisation. La répétabilité des mesures de réaction pour les individus était faible (~0,22 pour l’alerte et la fuite), ce qui indique que les variations modélisées étaient principalement dues à des variations intraindividuelles plutôt qu’interindividuelles. Nous avons noté une sensibilisation dans les réactions d’alerte avec le temps, mais aucune sensibilisation ou accoutumance dans les réactions de fuite. Nos résultats indiquent que les individus ont appris à anticiper l’approche d’un véhicule, mais n’ont pas modifié leur comportement d’échappement, ce qui porte à croire que les comportements d’alerte et de fuite des oiseaux pourraient être influencés différemment par des signaux associés à des objets se dirigeant vers eux ou par leur expérience individuelle de tels signaux. Nous discutons de nos constatations dans le contexte de l’élaboration de stratégies pour réduire les collisions entre animaux et véhicules. [Traduit par la Rédaction

Electrophysiological Heterogeneity of Fast-Spiking Interneurons: Chandelier versus Basket Cells

In the prefrontal cortex, parvalbumin-positive inhibitory neurons play a prominent role in the neural circuitry that subserves working memory, and alterations in these neurons contribute to the pathophysiology of schizophrenia. Two morphologically distinct classes of parvalbumin neurons that target the perisomatic region of pyramidal neurons, chandelier cells (ChCs) and basket cells (BCs), are generally thought to have the same "fast-spiking" phenotype, which is characterized by a short action potential and high frequency firing without adaptation. However, findings from studies in different species suggest that certain electrophysiological membrane properties might differ between these two cell classes. In this study, we assessed the physiological heterogeneity of fast-spiking interneurons as a function of two factors: species (macaque monkey vs. rat) and morphology (chandelier vs. basket). We showed previously that electrophysiological membrane properties of BCs differ between these two species. Here, for the first time, we report differences in ChCs membrane properties between monkey and rat. We also found that a number of membrane properties differentiate ChCs from BCs. Some of these differences were species-independent (e.g., fast and medium afterhyperpolarization, firing frequency, and depolarizing sag), whereas the differences in the first spike latency between ChCs and BCs were species-specific. Our findings indicate that different combinations of electrophysiological membrane properties distinguish ChCs from BCs in rodents and primates. Such electrophysiological differences between ChCs and BCs likely contribute to their distinctive roles in cortical circuitry in each species. © 2013 Povysheva et al