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Agrichemical Surfactant and Pathogen Impacts on the Blue Orchard Bee (\u3ci\u3eOsmia lignaria\u3c/i\u3e Say, Hymenoptera: Megachilidae)
Get PDFPathogens that infect commercially reared bee species, such as honey bees and bumble bees, have been extensively studied within the last several years, and studies that explore pathogen impacts on solitary bee health are significantly fewer. Consistent pesticide exposure methods are limited to honey bees and do not outline exposure routes to solitary bees, including how to test chemical impacts on immature stages. My research investigated blue orchard bee survival, development, and immune response following pathogen exposure while simultaneously studying organosilicone surfactant (OSS) exposure and possible synergisms between these two stressors. In my first research chapter (Chapter 2), I define methods to test OSS and pathogen oral exposure to the blue orchard bee (Osmia lignaria) in a laboratory setting. In Chapter 3, I investigated blue orchard bee development, survival, and immune responses following RNA virus exposure while studying OSS exposure and possible synergisms between these two stressors. Chapter 4 briefly discusses pathogens found in wild blue orchard bee populations and a dosage experiment to investigate how a pathogen inoculate, a filtrate from diseased honey bees, impacts blue orchard bees. In the second study year of Chapter 4, I added an OSS exposure group to evaluate how Apis mellifera filamentous virus (AmFV), a DNA virus, and its combination with OSS impact the development, survival, and immune response to laboratory-reared blue orchard bees. I document the first detection of AmFV in wild blue orchard bees and quantify relative amounts of AmFV from feeding assay and wild-caught bees. In my final research chapter (Chapter 5), I summarize a cautionary narrative from my research experience and define a critical time point in bee development for bee managers that propagate and sell solitary bees for pollination events. My dissertation develops reliable methods to test the impacts of pathogens, agrichemicals, and their interactions starting at the larval stage using an increasingly managed solitary bee. Additionally, I document the first detection of a DNA virus in wild and managed blue orchard bee populations. This finding highlights the urgent need to prevent any potential spread to bee populations during pollination events
Introduction to Drones
Get PDFUnmanned aircraft have advanced so much that they are completing tasks and integrating into all aspects of our lives. They deliver, survey, collect data, and complete assigned tasks with more efficiency and lower cost than many currently used techniques. The Federal Aviation Administration (FAA) completely supports UAS in the National Airspace System (NAS) and continually updates information in this new and exciting field. This fact sheet will help you identify how you can legally fly drones and become an integral part of aviation’s vast and ever-progressing world
Gravity Wave Breaking Over Northern Utah With an Advanced Mesospheric Temperature Mapper and Sodium Lidar
Get PDFConsiderable progress has been made in recent decades in the understanding of gravity wave (GW) dynamics. However, there remain important aspects and effects that are poorly understood. In particular, the coupling and deposition of their energy and momentum into the mesosphere lower thermosphere (MLT) region and the interaction and instability dynamics that are directly associated with GW breaking. Using an Advanced Mesosphere Temperature Mapper (AMTM) several strong wave breaking events were observed in the summer of 2015 at USU’s BLO research station. These events have exhibited high momentum fluxes and associated strong wave breaking, prompting detailed data analyses. Rossby waves, influenced by planetary rotation and Coriolis forces, along with tidal waves, driven by diurnal and semidiurnal solar heating, are analyzed due to their coupling interactions with GWs. However, the primary focus is to investigate the coupling of wave activity between the troposphere and MLT regions of the atmosphere, determine the role of critical layer filtering with the GW breaking events, and to analyze the strength and variation of momentum flux of the GW breaking events.
To further investigate the instabilities associated with these wave breaking events AMTM data is used in conjunction with sodium lidar data. With both the AMTM and lidar data the wind, temperature, and density measurements averaged in time are given from ∼80-105 km. This allows additional wave parameters to be resolved such as the natural frequency, Richardson number, and vertical wave number profiles. These gravity wave parameters are analyzed and reported for GWs exhibiting high momentum flux and energy deposition in the MLT region over northern Utah in 2015
Faculty Senate Executive Committee Minutes January 21, 2025
Get PDFCall to Order University Business Faculty Senate Business Information Report Old Business New Business Adjourn: 4:00 p
Effect of pH and Iron Chelate on the Growth of Basil and Soybean in Soilless Media
Get PDFIron (Fe) deficiencies are common in alkaline root zones and can cause chlorosis and reduce growth. The most common approach to prevent deficiency is using synthetic chelates that keep iron in solution at high pH. Here we report the effects of pH and chelate type on the development of chlorosis and biomass in soybeans and basil. We grew the plants at a pH ranging from 6.0-7.8. Fe was chelated with either a less expensive EDTA chelate or a more expensive EDDHA chelate. There was no significant difference between chelates at pH 6.0 in either soybeans or basil. In soybeans, there was no significant difference in biomass until the pH was increased to 7.8. In basil, there was a steady decrease in biomass as pH increased. Biomass was increased by EDDHA at a pH above 7. The lower cost EDTA can be used when pH is maintained. Fe sensitive species may require the more expensive EDDHA chelate when grown in alkaline conditions
Quantifying the Threshold for Fragmentation of Newtonian and Non-Newtonian Drops
Get PDFThis dissertation investigates how the properties of liquid drops influence the minimum aerodynamic forces needed to cause the drop to fragment (breakup). For this work, we focus only on aerodynamic forces that are applied on a stationary drop by a sudden, uniform flow, a process called impulsive acceleration. Previous studies have largely focused on the fragmentation of spherical drops of Newtonian fluids (liquids with constant viscosity, like water), when impulsively accelerated in air-like ambient medium. Such systems only capture a limited range of drop and ambient properties (described by non-dimensional groups). Many real-world applications, such as aerial fire retardant delivery, involve conditions beyond this typical range. Fire retardants, for instance, can exhibit shear-thinning behavior (their viscosity decreases under stress), and the drops undergoing fragmentation often start with a non-spherical shape. The ambient medium could also be one with much higher densities and viscosities, common in cases where liquid drops fragment in other liquids. Through this dissertation, we aim to utilize computational models, specifically interface-tracking multiphase flow direct numerical simulations (DNS), to systematically examine how various drop properties affect the threshold of secondary fragmentation.
The research is divided into five main parts. First, a model was developed to predict the trajectory and coverage of aerially delivered fire retardants, motivating the need for a deeper understanding of drop fragmentation. Second, we expanded the study of spherical, Newtonian drops beyond existing parameters, identifying a more robust non-dimensional parameter to predict the breakup threshold. Third, we performed the first systematic investigation of how initial drop shape affects fragmentation, quantifying its significant influence. Fourth and Fifth, we characterized the influence of shear-thinning or a viscoplastic nature of the drop fluid
Fact Sheet: Ketamine
Get PDFThis fact sheet discusses ketamine, which has pain-relieving properties and has gained recent attention for its antidepressant effects. However, as a Schedule III substance, it has a risk of strong psychological and physical dependence. Recreational use can lead to short- and long-term effects on health and risk of overdose and death
Characterization and Calibration of the AirHARP2 Suite of Instruments
No full textAirHARP2 is the aircraft version of the orbital Hyper Angular Rainbow Polarimeter (HARP2) on NASA’s Plankton Aerosol Cloud and ocean Ecosystem (PACE) satellite. In September 2024, AirHARP2 participated in the PACE Postlaunch Airborne eXperiment (PAX). This campaign provides a unique opportunity to validate radiometric and polarimetric measurements and derived science products from the PACE satellite by conducting direct cross-platform comparisons using co-located scenes. AirHARP2 is the polarimeter instrument in the AirHARP2 Suite, which also contains a VNIR imaging spectrometer, UV imaging spectrometer, and a SWIR multi-angle imaging radiometer. The companion instruments in the AirHARP2 suite mirror spectral response of the PACE Ocean Color Instrument (OCI). The full AirHARP2 suite underwent spectral calibration using the Goddard Laser for Absolute Measurement of Radiance (GLAMR) laboratory. GLAMR consists of multiple tunable lasers across the solar spectrum. Radiometric calibration for the AirHARP2 suite was performed using a calibrated integrating sphere. This presentation describes the calibration methods used for the AirHARP2 suite and shows the current state of the calibration
Optical Power Scale Realization at NIST Using the Primary Optical Watt Radiometer (POWR)
No full textThe Primary Optical Watt Radiometer (POWR) [1] at NIST realizes and maintains the unit of optical power (watt). POWR is an absolute cryogenic radiometer which uses the principle of electrical substitution to obtain the total power of input optical radiation. It serves as the basis for many radiometric and photometric units and scales realized at NIST, providing optical power measurements with uncertainties as low as 0.02% (k = 1) for continuous wave laser inputs. Currently, a continuously tunable and computer controlled supercontinuum light source is routinely utilized for efficient data collection between 500 nm and 1700 nm (5 nm step size), and a system with a Ti:Sapphire laser/ harmonic generation can produce specific wavelengths in the ultraviolet regime. These measurements are then used to calibrate the optical power responsivity of photodetectors (e.g. Si and InGaAs photodiodes) which serve as standards at NIST and beyond. This talk will introduce electrical substitution and absolute cryogenic radiometers and discuss the role POWR plays in the optical power calibration chain. Case data and lessons learned will be presented for the diverse radiation sources (ultraviolet to near infrared) available for use with POWR. Research in the POWR lab aims to lower the uncertainties in optical power measurements and calibrations whilst streamlining the data collection; future improvements to further this goal will be discussed and include incorporating a closed-cycle cryostat and continuous and automated wavelength coverage between 190 nm and 2300 nm.
1. J. M. Houston and J. P. Rice 2006 Metrologia 43 S31 DOI: 10.1088/0026-1394/43/2/S0
CNES Participation to the Sentinel-2 C Commissioning Phase, Leveraging Synergies Between Vicarious Calibration Methods
No full textThe 5th September 2024, Sentinel-2 C has successfully joined its orbit where Sentinel-2 A and B were already in operation since 2015 and 2017 respectively. The Sentinel-2 mission is part of the European Copernicus program, a wide Earth observation program dedicated to the environment monitoring, the mitigation of climate change effects and a support to emergency services. Sentinel-2 handles the high-resolution optical component with an acquisition of the Earth surface in 13 different spectral bands, every 5 days with a spatial resolution between 10 m and 60 m (depending on the band).
The French space agency (CNES) was in charge of the commissioning phase for the first two Sentinel-2 units. For Sentinel-2 C, the European Space Agency (ESA) has led the commissioning phase and CNES has brought its support with an independent radiometric validation. The main goal in a multi-satellite constellation remains the radiometric cross-calibration of every instrument so that users can process data regardless of the instrument. A tandem phase acquisition between Sentinel-2 C and Sentinel-2 A has helped a lot to align the radiometry of the two satellites. The presentation will go through the 5 vicarious calibration methods applied by CNES and the associated results.
The cross-calibration among the Sentinel-2 family as well as between Sentinel-2 C and other reference sensors such as Landsat 8, Landsat 9, Sentinel-3, MERIS is studied on Pseudo-Invariant Calibration Sites (PICS), both hot and cold deserts. The absolute calibration is evaluated with the Rayleigh scattering and the instrumented sites measurements. The inter-band calibration is measured with the Deep Convective Clouds (DCC) approach. And, for the first time in the Sentinel-2 family, several Moon images were acquired with Sentinel-2 C. CNES has applied the techniques developed in the frame of the Pleiades mission to these images and shown the radiometric coherence of Sentinel-2 with the Moon irradiance model. The presentation will help to understand the various radiometric validation methods at stake but also the reason for combining them during a commissioning phase: validity domain of each method, data availability, sensibility to error sources (especially the spectral aspects which were particularly well characterised on-ground for the Sentinel-2 C instrument). Besides, the presented results will help users who may want to build consistent time series, combining data from various reference sensors, including Sentinel-2 satellites.
The commissioning phase is always a thrilling period with a lot of in-depth studies, numerous exchanges with the various actors and a combination of results to tune the satellite. Sharing this experience with the community participates to improve the radiometric calibration methods as well as to enable the users to better understand the data. Sentinel-2 C is now aligned within 1 % with the two others Sentinel-2