Management of Insecticide-Resistant Soybean Aphids in the Upper Midwest of the United States

Since the first observation of soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), in North America in 2000, it has become the most economically damaging insect of soybean in the Upper Midwest of the United States. For the last 17 yr, soybean aphid management has relied almost entirely on the use of foliar-applied broad-spectrum insecticides. However, in 2015 in Minnesota, failures of foliar-applied pyrethroid insecticides were reported and pyrethroid resistance was confirmed with laboratory bioassays using lambda-cyhalothrin and bifenthrin. In 2016 and 2017, further reports of failures of pyrethroid insecticides and/or laboratory confirmation of resistance occurred in Iowa, North Dakota, South Dakota, and Manitoba. In response to the challenge posed by insecticide-resistant soybean aphids, we recommend several management strategies for minimizing further development of resistance and subsequent pest-induced crop losses: 1) scout and use the economic threshold to determine when to apply insecticides, 2) apply the insecticides properly, 3) assess efficacy 3–5 d after application, and 4) alternate to a different insecticide group if another application is required. In the long term, soybean aphid management must move beyond insecticide-based management to true integrated pest management by incorporating multiple tactics

Scaled-up expansion of equine cord blood mesenchymal stem cells (MSCs) from stirred suspension bioreactors to 100mL computer controlled stirred suspension bioreactors using computational fluid dynamic modeling

Musculoskeletal injuries are the leading cause of lameness and loss of performance in horses and conventional treatments are often associated with high rates of re-injury. Mesenchymal Stem Cells (MSCs) have shown promise for the treatment of such injuries in horses. Currently, the majority of studies are focused on the use of either bone-marrow derived or adipose-derived MSCs. However, equine cord-blood derived MSCs (eCB-MSCs) also provide a promising alternative, due to their high proliferation potential, ability to differentiate towards the chondrogenic lineage, and comparable immune-modulatory properties. Static adherent culture of eCB-MSCs has limited potential to produce sufficient cell numbers for large-scale research studies and possible commercial distribution. Expansion of cells in stirred suspension bioreactors using microcarriers as a scaffold has the potential to generate a large number of cells, using a significantly smaller space, under highly controlled conditions, with reduced time, labour, and monetary requirements. A robust protocol is required for the expansion of eCB-MSCs for use in large research studies and commercial applications. Initially, the hydrodynamic environment in the 10mL and the 100mL bioreactors was modeled using COMSOL Multiphysics software. The volume distributions of shear stress and energy dissipation rate in the bioreactors were calculated and used to determine the operating conditions that would create similar conditions within both scales of bioreactors. Next, eCB-MSCs were expanded in 10mL stirred suspension bioreactors and run at 60rpm and 80rpm with two different impeller geometries: paddles and rounded edges. The bioreactors were loaded at 4500 cells/cm2, and 2g/L microcarriers. The cells at different operating conditions in the 10mL bioreactors achieved varying population doubling times ranging from 0.8d to 1.1d with an average of 0.9d and initial cell attachment ranging from 5000 cells/cm2 to 7700 cells/cm2. The different speeds and geometries produced varying results with maximum attached cell densities from 35,000 to 50,000 cells/cm2 in the bioreactors, compared to maximum cell densities of 44,000 cells/cm2 achieved instatic growth. The expansion of eCB-MSCs was then scaled up in 100mL stirred suspension bioreactors with no direct pH or dissolved oxygen control, using 4500 cells/cm2 and 2g/L microcarriers, with a speed of 40rpm. At this larger scale, the initial cell attachment was 6900 cells/cm2 compared to 6300 cells/cm2 for the 10mL bioreactor. With respect to initial cell attachment, the 100mL bioreactor at 40rpm was most similar to the condition of 80rpm with round edge impeller geometry. The highest attached cell density in the 100 mL vessel was 70,000 cells/cm2. The 100mL uncontrolled bioreactor at 40rpm achieved the most similar results to the 10mL bioreactor run at 60rpm with paddled geometry, with respect to population doubling time with a doubling time of 0.93d for the 10mL bioreactor compared to 0.92d for the 100mL bioreactor. Finally, the eCB-MSCs were expanded in 100mL stirred suspension bioreactors at 4500 cells/cm2, 2g/L and 40rpm with pH and oxygen controlled at 7.4 and 21% DO, respectively, using the DASGIP bioreactor control system. This series of experiments revealed that eCB-MSCs can be expanded in stirred suspension bioreactors

Modelling Response Properties Across the Orientation Map in Visual Cortex

Stimulus orientation in the primary visual cortex of primates and carnivores is mapped as iso-orientation domains radiating from pinwheel centers, where orientation preferences of neighboring cells change circularly. Whether this orientation map has a function is debated, because many mammals, such as rodents, do not have such maps. Here we model our physiological results that two fundamental properties of visual cortical responses, contrast saturation and cross-orientation suppression, are stronger within iso-orientation domains than at pinwheel centers. Our model expands on a standard thalamic model of cross orientation suppression, and explains differences between orientation domains by intra-cortical excitation (not normalization) from neighboring oriented neurons, balanced by inhibition from un-oriented neurons. The functions of the pinwheel mosaic can be inferred from the model’s outputs: Narrower tuning, greater cross-orientation suppression and higher contrast gain of iso-orientation cells, lead to extraction of extended object contours from images. In contrast, broader tuning, greater linearity and less suppression of pinwheel cells generate selectivity for surface patterns and textures

Construction and Nursing Students, Building a Playground for Bauer Family Services

Poster Sessio

Divergent Switchgrass Cultivars Modify Cereal Aphid Transcriptomes

Schizaphis graminum Rondani (Hemiptera: Aphididae) and Sipha flava Forbes (Hemiptera: Aphididae) are two common pests of bioenergy grasses. Despite the fact that they are both considered generalists, they differ in their ability to colonize Panicum virgatum cultivars. For example, S. flava colonizes both P. virgatum cv. Summer and P. virgatum cv. Kanlow whereas S. graminum can only colonize Summer. To study the molecular responses of these aphids to these two switchgrass cultivars, we generated de novo transcriptome assemblies and compared the expression profiles of aphids feeding on both cultivars to profiles associated with feeding on a highly susceptible sorghum host and a starvation treatment. Transcriptome assemblies yielded 8,428 and 8,866 high-quality unigenes for S. graminum and S. flava, respectively. Overall, S. graminum responded strongly to all three treatments after 12 h with an upregulation of unigenes coding for detoxification enzymes while major transcriptional changes were not observed in S. flava until 24 h. Additionally, while the two aphids responded to the switchgrass feeding treatment by downregulating unigenes linked to growth and development, their responses to Summer and Kanlow diverged significantly. Schizaphis graminum upregulated more unigenes coding for stress-responsive enzymes in the Summer treatment compared to S. flava; however, many of these unigenes were actually downregulated in the Kanlow treatment. In contrast, S. flava appeared capable of overcoming host defenses by upregulating a larger number of unigenes coding for detoxification enzymes in the Kanlow treatment. Overall, these findings are consistent with previous studies on the interactions of these two cereal aphids to divergent switchgrass hosts

Towards an equity competency model for sustainable food systems education programs

Addressing social inequities has been recognized as foundational to transforming food systems. Activists and scholars have critiqued food movements as lacking an orientation towards addressing issues of social justice. To address issues of inequity, sustainable food systems education (SFSE) programs will have to increase students’ equity-related capabilities. Our first objective in this paper is to determine the extent to which SFSE programs in the USA and Canada address equity. We identified 108 programs and reviewed their public facing documents for an explicit focus on equity. We found that roughly 80% of universities with SFSE programs do not provide evidence that they explicitly include equity in their curricula. Our second objective is to propose an equity competency model based on literature from multiple fields and perspectives. This entails dimensions related to knowledge of self; knowledge of others and one’s interactions with them; knowledge of systems of oppression and inequities; and the drive to embrace and create strategies and tactics for dismantling racism and other forms of inequity. Integrating our equity competency model into SFSE curricula can support the development of future professionals capable of dismantling inequity in the food system. We understand that to integrate an equity competency in our curricula will require commitment to build will and skill not only of our students, but our faculty, and entire university communities

Self-Regulation of Emotion, Functional Impairment, and Comorbidity Among Children With AD/HD

Objective: This study investigated the role of self-regulation of emotion in relation to functional impairment and comorbidity among children with and without AD/HD. Method: A total of 358 probands and their siblings participated in the study, with 74% of the sample participants affected by AD/HD. Parent-rated levels of emotional lability served as a marker for self-regulation of emotion. Results: Nearly half of the children affected by AD/HD displayed significantly elevated levels of emotional lability versus 15% of those without this disorder. Children with AD/HD also displayed significantly higher rates of functional impairment, comorbidity, and treatment service utilization. Emotional lability partially mediated the association between AD/HD status and these outcomes. Conclusion: Findings lent support to the notion that deficits in the self-regulation of emotion are evident in a substantial number of children with AD/HD and that these deficits play an important role in determining functional impairment and comorbidity outcomes