Assessing the long-distance repellency of long-lasting insecticide netting to a suite of post-harvest insects

Insects are our main competitors for food on the planet (1). In fact, growers lose 10-30% of crops during storage, processing, and marketing after harvest each year to stored product insects (2,3). Challenges to current management include increasing insecticide resistance to phosphine (4), which is the most common insect fumigant. Another challenge has been an increasing demand for organic or low insecticide-input products by consumers (5). To meet these challenges we came up with an alternative management approach, a long lasting insecticide netting (LLIN). Insecticide-treated nets have been widely used as a tool for malaria vector control in tropical regions since the early 1990s (6). These nets are typically treated with a pyrethroid insecticide, such as permethrin or deltamethrin, which repel, incapacitate, and kill mosquitoes that land on the nets. Researchers have recently begun exploring the use of LLINs for management of agricultural pests in high value specialty crops (7). More recently, work with LLINs in post-harvest settings has demonstrated that this tool can induce mortality, as well as significantly decrease the movement and dispersal capacity of post-harvest insects (8). Some possible uses for LLIN include being used to line windows, vents, eaves, or other openings into food facilities. However, anecdotal evidence from IPM practitioners has suggested that pyrethroids, which the LLIN contains, may be repellent to specific groups of insects. In order for LLIN to be an effective tool at intercepting and preventing infestation by stored product insects, we must demonstrate that the netting is not repellent to a range of post-harvest insects

Elucidating the behavioral response of stored product insects to fungal volatiles in the wind tunnel and simulated warehouses

Post-harvest pest insects can cause significant amounts of damage to stored products in and around food facilities, reducing quantity and quality of grains. Post-harvest insects have been attributed to billions of dollars in agricultural loss via yield loss and the cost of mitigation measures. Early detection of insect pests is crucial to preventing infestations and losses since some species of stored product pests are becoming resistant to common control options. Numerous detection methods are available, but many are time consuming and ineffective, leading to a need for more effective and practical monitoring methods. Grain oils have been used to induce behavioral responses in the red flour beetle (Triboliumcastaneum) and the lesser grain borer (Rhyzoperthadominica), but fungal volatiles may be an even stronger attractant to these species

Potential repellency of cedarwood oil from a novel extraction method to stored product insects

Producers lose 10-30% of crops during storage, processing, and marketing after harvest each year to stored product insects (1,2). Globally, there has been a rise in insecticide resistance to phosphine, the most common fumigant for these pests (3). As a result, producers need to diversify post-harvest IPM methods to preserve existing tools. One alternative strategy is push-pull, whereby a repellent is used to “push” an insect away from the commodity of interest, while also simultaneously “pulling” the insects to an alternate location away from the commodity using an attractant (4)(Fig. 1). This system notably requires a long-distance repellent. One potential repellent includes cedarwood oil, which has shown repellency to termites and ants (5,6). A novel extraction process for this compound has been developed, which leaves many of its main constituents intact (7). However, to date, this compound has never been assessed for repellency to post-harvest insects

Experimental study of the flow field inside a whirling annular seal

The flow field inside a whirling annular seal was measured using a 3-D Laser Doppler Anemometer (LDA) system. The seal investigated has a clearance of 1.27 mm, a length of 37.3 mm, and is mounted on a drive shaft with a 50 percent eccentricity ratio. This results in the rotor whirling at the same speed as the shaft rotation (whirl ratio = 1.0). The seal is operated at Reynolds number of 12,000 and a Taylor number of 6,300 (3,600 rpm). The 3-D LDA system is equipped with a rotary encoding system which is used to produce phase averaged measurements of the entire mean velocity vector field and Reynolds stress tensor field from 0.13 mm upstream to 0.13 mm downstream of the seal. The mean velocity field reveals a highly three dimensional flow field with large radial velocities near the inlet of the seal as well as a recirculation zone on the rotor surface. The location of maximum mean axial velocity migrates from the pressure side of the rotor at the inlet to the suction side at turbulence kinetic energy. However, turbulence production and dissipation attain equilibrium fairly quickly with remaining relatively constant over the last half of the seal

Turbulence measurements of high shear flow fields in a turbomachine seal configuration

The mean velocity and Reynolds stress tensor throughout a whirling annular seal are presented. The data was collected with a three dimensional laser Doppler velocimeter using phase averaging. Two axial flow conditions (Re = 12,000 and 24,000) were studied at one shaft speed (Ta = 6,600). The eccentricity and whirl ratios were 50 and 100 percent, respectively. There is a region of high axial momentum in this region is higher in the low Reynolds number case due to an axial recirculation zone that occurs on the suction side of the rotor at the inlet. The recirculation zone does not occur in the high Reynolds number case. At both Reynolds numbers, there is a recirculation zone on the rotor surface in the pressure side of the inlet. This recirculation zone extends from 20 to 200 degrees rotor zenith in the tangential direction, and is one third of a clearance wide radially. The high Reynolds number recirculation zone is 1.5 mean clearances long, while the low Reynolds number zone extends 2 mean clearances downstream. When compared to previous studies, it is apparent that the tangential momentum is no greater for a seal with whirl than for one without if other parameters are constant. Areas of high tangential momentum occur in the clearance where the axial momentum is low. Average exit plane tangential velocities in the high Reynolds number case are 1.5 times greater than those in the other flow case. These results are in general agreement with predictions made by other investigators

The impact of follow-up calls after a pediatric emergency department visit

Pediatric emergency department (ED) visits can be a stressful time for patients and their caregivers. This high stress environment can lead to questions and needed clarifications post-discharge. We implemented a post-discharge callback system to resolve these concerns for a focused subset of patients who historically have provided the most negative comment feedback on ED patient experience surveys. We hypothesized that comment types would shift to more positive than negative and the themes of the comments received would change. We developed a discharge callback process that focused on patients who were triaged as ESI level 4 during their emergency department visit. Over a 6-week period, patients were called the day after discharge and asked if they had questions regarding their recent ED visit in addition to questions regarding current health, post-discharge instructions, prescriptions, or follow-up instructions if applicable. A maximum of 3 discharge calls were made if needed in order to contact the patient or family. Any questions regarding health care needs were followed up by a licensed healthcare provider within 24 hours with a maximum of 3 attempts. At the end of the project timeframe we analyzed comments received from our patient experience surveys to identify if there was a shift in comment types and their themes. In addition, we analyzed ED return rates within 72 hours of discharge. During the 6-week period, 2710 calls were made to contact 1618 patients’ caregivers. Follow up was requested by 149 families with a healthcare provider. There was no significant change in the number of comment types received. Thematic analysis of the patient experience survey comments received during this time period, revealed a reduction in questions regarding the recent ED visit and post discharge needs. There was no significant change in 72-hour ED return rates. The institution of an ED discharge callback system can effectively reduce patients’ and families’ questions regarding post-discharge care by providing an opportunity to clarify care after they have left the emergency department. Experience Framework This article is associated with the Patient, Family & Community Engagement lens of The Beryl Institute Experience Framework (https://www.theberylinstitute.org/ExperienceFramework). Access other PXJ articles related to this lens. Access other resources related to this lens

The use of long-lasting insecticide netting to prevent dispersal of stored product insects: Poster

The lesser grain borer, Rhyzopertha dominica, and red flour beetle, Tribolium castaneum, are two notorious primary and secondary pests of stored products. Extensive research has been done to prevent the establishment and subsequent infestation of the insects in stored product facilities. Long-lasting insecticide netting (LLIN) on mosquitoes has proved effective in controlling the spread of malaria, but little research has been conducted on the LLIN’s behavioral effects of stored product insects. In this study, a movement and dispersal assay were performed. In the movement assay, the video-tracking software, Ethovision, recorded the movement of R. dominica and T. castaneum after 1-10 min exposures to LLIN or control netting and a waiting period of 1 min, 24 hr, 72 hr, or 7 days after netting exposure. In the dispersal assay, R. dominica and T. castaneum were observed after 5 minutes of exposure to LLIN or control netting to measure the insects’ ability to reach new food patches at three different distances. The results from the movement assay showed a significant reduction in horizontal movement and significant increase in angular velocity for beetles exposed to LLINs, indicating that movements were more erratic and less directed. The dispersal assay revealed that exposure to LLIN had a significant effect on the dispersal ability of both R. dominica and T. castaneum with averages of 0-3 from a group of 20 beetles reaching the new food patch. These results indicate that LLINs can be an effective tool for the prevention of stored product insect establishment and colonization.The lesser grain borer, Rhyzopertha dominica, and red flour beetle, Tribolium castaneum, are two notorious primary and secondary pests of stored products. Extensive research has been done to prevent the establishment and subsequent infestation of the insects in stored product facilities. Long-lasting insecticide netting (LLIN) on mosquitoes has proved effective in controlling the spread of malaria, but little research has been conducted on the LLIN’s behavioral effects of stored product insects. In this study, a movement and dispersal assay were performed. In the movement assay, the video-tracking software, Ethovision, recorded the movement of R. dominica and T. castaneum after 1-10 min exposures to LLIN or control netting and a waiting period of 1 min, 24 hr, 72 hr, or 7 days after netting exposure. In the dispersal assay, R. dominica and T. castaneum were observed after 5 minutes of exposure to LLIN or control netting to measure the insects’ ability to reach new food patches at three different distances. The results from the movement assay showed a significant reduction in horizontal movement and significant increase in angular velocity for beetles exposed to LLINs, indicating that movements were more erratic and less directed. The dispersal assay revealed that exposure to LLIN had a significant effect on the dispersal ability of both R. dominica and T. castaneum with averages of 0-3 from a group of 20 beetles reaching the new food patch. These results indicate that LLINs can be an effective tool for the prevention of stored product insect establishment and colonization

Evaluating Multiple Arthropod Taxa as Indicators of Invertebrate Diversity in Old Fields

Biodiversity, often quantified by species richness, is commonly used to evaluate and monitor the health of ecosystems and as a tool for conservation planning. The use of one or more focal taxa as surrogates or indicators of larger taxonomic diversity can greatly expedite the process of biodiversity measurement. This is especially true when studying diverse and abundant invertebrate fauna. Before indicator taxa are employed, however, research into their suitability as indicators of greater taxonomic diversity in an area is needed. We sampled invertebrate diversity in old fields in southern Michigan using pitfall trapping and morphospecies designations after identification to order or family. Correlation analysis was used to assess species richness relationships between focal arthropod taxa and general invertebrate diversity. Relationships were assessed at two fine spatial scales: within sampling patches, and locally across four sampling patches. Cumulative richness of all assessed taxa increased proportionately with cumulative invertebrate richness as sampling intensity increased within patches. At the among-patch scale, we tentatively identified Hemiptera and Coleoptera as effective indicator taxa of greater invertebrate richness. Although Hymenoptera, Araneae and Diptera exhibited high species richness, their total richness within patches was not associated with overall invertebrate richness among patches. Increased sampling throughout the active season and across a greater number of habitat patches should be conducted before adopting Hemiptera and Coleoptera as definitive indicators of general invertebrate richness in the Great Lakes region. Multiple sampling techniques, in addition to pitfall trapping, should also be added to overcome capture biases associated with each technique