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Seed Corn Maggot in Spring Melons
No full textThis IPM short provides updated information on the biology, damage potential, and management strategies for seed corn maggot (Delia platura) in spring melon production systems of the desert Southwest. The pest can cause serious injury to germinating seeds and transplants under cool, moist conditions, often exacerbated by high levels of organic matter. The publication outlines risk factors, preventive cultural practices, and effective insecticidal treatments to mitigate early-season losses in melon crops.Documents in the Arizona Pest Management Center collection are made available by the Arizona Pest Management Center (APMC) and the University Libraries at the University of Arizona. For more information about items in this collection, please contact https://acis.cals.arizona.edu/about-us/arizona-pest-management-center
Ore Permittivity and Copper Detection on Leaching Using Radio-Frequency Sensor
No full textThe extraction of copper through leaching has become increasingly important due to the rising demand for this essential mineral to drive global efforts towards decarbonization and electrification. Accurate measurement of variables is crucial for process control, necessitating the development of advanced sensor technologies. This document presents research on state-of-the-art radio-frequency and microwave sensors designed for copper detection, with a focus on copper leaching scenarios. The research begins with a review of the implementation of dielectric permittivity measurements in the mining industry, highlighting their potential to enhance the monitoring and optimization of copper leaching processes. It evaluates the suitability of permittivity-based sensors, examining their benefits and limitations, and discusses their implications for process control and economic optimization. Following this, the document presents the implementation results of a radiofrequency probe aimed at determining the correlation between copper variation in column testing scenarios. Multivariable regressors were integrated to uncover the dynamics and establish regression models for predicting copper concentration in Pregnant Leach Solution (PLS) based on Vector Network Analyzer (VNA) readings at 1 MHz.Release after 07/14/202
Microbial Water Quality Assessment and Molecular Assay Optimization for Vibrio Cholerae Detection
No full textAccess to clean water and adequate sanitation is critical for public health, yet microbial contamination of water sources remains a pervasive challenge, particularly in developing regions like Sub-Saharan Africa. One of the most devastating consequences of this contamination is cholera- a severe diarrheal disease that causes rapid dehydration and is considered one of the fastest fatal infections if not treated immediately. This study investigates the microbial water quality and its associated health risks within various water sources in Dar es Salaam, Tanzania. The objective of this study was to 1) Conduct microbial water quality assessment to identify and quantify the presence of total Coliforms and fecal coliform indicator (E. coli), in water samples collected from various district locations to improve public health; 2) assess risks to diarrhea diseases associated with water sources in these districts; and 3) optimize a molecular assay for the detection of Vibrio cholerae (V. cholerae) and testing primer concentration using SimpliAmp and Bio-Rad Polymerase Chain Reaction (PCR) platforms. A total of 160 water samples were assessed for microbial water quality by testing for the presence of Total Coliform (TC) and Escherichia coli (E. coli) using the Colilert method. E. coli results were used to determine the risk for diarrhea diseases using the World Health Organization (WHO) guidelines. For detection of V. cholerae, four biomarkers, ompW, ctxA, O1 and 0139 genes were targeted for optimization using PCR.
Overall, 66.9% of samples tested positive for Total coliforms while, 37.4% were positive with E. coli contamination. Among the three districts, Kinondoni recorded significantly higher TC compared to both Ilala (Z = -4.73, p < 0.001) and Temeke (Z = 5.06, p < 0.001) respectively. Similarly, significant higher levels of E. coli were recorded in Kinondoni compared to Ilala (Z = -7.93, p < 0.001) and Temeke (Z = 7.99, p < 0.001). All samples from the stream showed an intermediate risk level for disease, followed by 27.9% of open wells samples and 6.7% of public taps. All water samples from closed wells and vendors were in conformity with WHO guidelines and, therefore, considered safe.
Our optimized PCR assay for V. cholerae detection, reduced cycling time for the multiplex assay (ctxA, O1 and O139) from the baseline study by 30 seconds for denaturation and annealing time, while extension time was reduced by 15 seconds. Higher annealing temperature was also achieved for ompW and the multiplex assays from our baseline. Our assay detected clear/strong bands for ompW between 1 µM (baseline concentration) to 0.5 µM and is sensitive enough to detect the presence of V. cholerae with 299 gBlocks copies or bacteria cells. We observed a comparable performance on both thermocycler platforms.
Our results show evidence of fecal contamination. While samples purchased from vendors and those from close wells were safe for consumption, other water sources have low to intermediate risk to diarrheal diseases. With fewer reagents and a cost-effective thermocycler, costs will be reduced, and more reagents can be saved to assess other samples, which could enhance more surveillance, outbreak identification, and response to potential cholera outbreaks, thereby potentially preventing widespread transmission, lowering mortality, and lessening the strain on already overburdened health systems.
By monitoring the levels of coliforms and E. coli in these water sources, this study has provided valuable insights into the level of fecal contamination and the potential health risk it poses to individuals in these communities that rely on these water sources both for drinking, cooking, and recreation. There is an urgent need for a concerted effort at the household, community, and government levels to improve access to quality water for all.
Release after 04/27/202
Effectiveness of Evidence-Based Compassion Resilience Intervention on CRNA Perceived Stress
No full textPurpose. This quality improvement project aimed to evaluate an evidence-based wellness
educational program to lower anesthesia providers’ perceived stress and increase compassion
resilience practices.
Background. It is well-documented that chronic and unmanaged stress can lead to psychological
and physiological consequences that negatively impact Certified Registered Nurse
Anesthesiologists’ (CRNA) performance and well-being (Griffen et al., 2017; Jun et al., 2020;
Stillwell et al., 2017). High stress levels are commonly reported among new-graduate and
experienced CRNAs, leading to undesirable adverse effects, such as anxiety, depression, panic
disorders, suicidal thoughts, sleep disturbances, and addictive behaviors (Jun et al., 2020). With
CRNAs being twice as likely to suffer from depression and having a higher suicide rate, a
proactive approach to CRNA and healthcare provider well-being is needed (Davidson et al.,
2021).
Methods. Participants were chosen through convenience sampling. A pre-survey with a
Perceived Stress Scale (PSS) was distributed. Participants then underwent a five-day intervention
that included educational sessions on mindfulness, yoga, and stress management techniques
worth 20 continuing education (CE) credits. Following the intervention, participants completed a
post-survey, including a PSS reassessment. Data analysis was completed using descriptive
statistics and a paired t-test.
Results. When comparing participants’ pre- and post-intervention assessments, 90% (n=18) had
a reduction, 5% (n=1) had no change, and 5% (n=1) had an increase in their perceived stress
scale (PSS) scores. On average, the PSS scores decreased by 12.4 points (44.5%), with many
12
participants’ scores going from moderate or high levels of perceived stress to low levels post-
intervention (p < 0.001).
Conclusions. The five-day retreat in South Casco, Maine, significantly benefited retreat
participants in improving compassion resilience and lowering levels of perceived stress (p <
0.001). This project also sets the stage for future research and sustainable achievements in
CRNA compassion resilience and well-being
Enhancing the Detection of Contamination Events in Water Distribution Systems by Integrating Alternative Sources of Information in Real-Time
No full textWater distribution systems (WDS) are one of the most vulnerable components of water infrastructure systems. After the events of 9/11, there was increased concern regarding the potential for the deliberate introduction of chemical agents that may affect public health. Later, these concerns moved towards accidental water quality incidents produced by, for example, cross-connections and low-pressure events. In either case, Surveillance Response Systems (SRS) were formulated to protect water quality by make prompt detection and confirmation of contamination events. The overall objective of this dissertation is to develop a decision framework capable of making a timely detection, confirmation and forecasting of a contamination event in WDS. The fulfilment of this objective relied on the use of confirmatory sampling locations (CSLs) as a way to overcome the limitations of traditional water quality monitoring, which includes the high cost of sensors and limited detection capabilities due to the lack of contaminant-specific sensors. Based on previous research that provided a foundation to identify the best individual CSL using an entropy metric derived from information theory, this dissertation proposed the Updating Greedy Algorithm (UGA) to identify a set of \emph{multiple} CSLs in real-time. The UGA used an approximation to the entropy metric and a greedy heuristic to identify the set of CSLs. When tested on a small network, the UGA results were almost identical to the solutions achieved by a Genetic Algorithm using an exact formulation of the entropy metric, but in orders of magnitude less time. As the number of CSLs increased, the placements were spatially very similar (similar hydraulic paths), which may lead to a potential overlap of information across the CSL. To enable the implementation of the UGA in real-sized networks, the UGA was extended into a cluster-based optimization approach in order to reduce the solution space. The clustering algorithm grouped the network nodes based upon similarities in hydraulic connectivity. Each cluster was then assigned a representative sampling unit within each cluster to be used as a potential CSL. Two types of sampling units were used: i) the centroids of the cluster and ii) the location within the cluster that maximized information gain. The use of the clusters and sampling units were proposed to reduce the computational burden of the algorithm while maintaining a similar set of spatially distributed potential CSL. Ultimately, this approach was tested on a large network, and was shown capable of generating optimal solutions within an amount of time consistent with real-time application (1 hour). Finally, the reduction of information overlap was investigated through the introduction of the Multi-Objective Updating Greedy Algorithm (MUGA). The MUGA incorporated D-optimality, a correlation metric, to increase the spatial distribution of CSLs across the network while maximizing the amount of information gained from the samples. The trade-off between Information Gain and D-Optimality showed that the information gain tended to place CSLs along similar hydraulic paths, reinforcing existing connections, whereas the maximization of D-Optimality placed CSLs in unexplored hydraulic paths, creating new connections. The MUGA was tested in a large network using the clustering approach previously developed. The MUGA approach was shown to be computational efficient, and able to achieve good results (relative to Genetic Algorithm solutions). Overall, the addition of the D-optimality was capable of spatially distribution the CSLs and, at lower weights, was able to help avoid some local minima when using the Information Gain as a single objective. Overall, the deployment of CSLs provides useful information to characterize a contamination event, that enhances detection, confirmation and forecasting capabilities of SRS. These methodologies must be efficient enough to provide good solutions in at a time frame useful for real-time application. This research developed an approximation to the exact solution for information gain, a clustering approach to reduce the solution space of large networks, a greedy heuristic placement algorithm, and a multi-objective placement algorithm that that were shown capable of generating good CSL solutions in less than an hour -- often in seconds for the single objective placement. Further research may explore the response of the proposed approaches under diverse characteristics of a contamination event (varying injection locations and times), as well as considering demand uncertainty. Finally, as some contaminants may remain undetected, the inclusion of alternate data sources (e.g., public health data) may be integrated to enhance detection capabilities of SRS
THE LAMBERT PROBLEM OF ORBITAL DYNAMICS
No full textWhen considering space travel between two celestial bodies under a gravitational potential, Lambert's problem asks if there exists a way to free fall between the two bodies. Keplerian dynamics ensures that this free fall trajectory describes a conical arc. The Lambert equation provides a solution to this problem that relates travel time and the energy necessary for this fall to occur. We will introduce the physical concepts of motion under a gravitational potential and a characterization of conic sections in terms of a parameter known as eccentricity. Using conservation properties, we will show that free fall under a gravitational potential must follow a conical trajectory. Therefore, Lambert's problem can be rephrased as determining the energy required to place the vessel on the desired conical orbit connecting the two bodies. We will then show Lagrange's solution algorithm which yields the required energy as a function of the departure and arrival dates. We conclude by showing how this is a relevant problem in orbital mission planning
UNDERGRADUATE STUDENT EXPERIENCE WITH POLYCYSTIC OVARIAN SYNDROME
No full textThis thesis investigates college-aged women enrolled at the University of Arizona and their experiences with Polycystic Ovarian Syndrome (PCOS), focusing on their awareness of the condition and lifestyle habits. PCOS is a very common endocrine disorder which can lead to long-term health complications if left undiagnosed and unmanaged. Through a survey, data was gathered on student knowledge of PCOS, physical activity levels, and experiences with PCOS symptoms. Results revealed that a significant portion of students, both diagnosed and undiagnosed, exhibit symptoms of PCOS, but 81% reported feeling uninformed about the PCOS. The analysis also showed that while many students engage in some form of physical activity, a lack of awareness may contribute to suboptimal health behaviors. This thesis underscores the need for increased education on PCOS and highlights the importance of lifestyle interventions like exercise and diet in managing the condition. The findings suggest that improving awareness and support within the college environment could lead to better health outcomes for students with PCOS
ROTATIONALLY RESOLVED VISIBLE AND NEAR-INFRARED SPECTROSCOPIC CHARACTERIZATION OF ASTEROID (223) ROSA
No full textWe present the results of our April, 2023 spectroscopic observation campaign in the form of four quarter-phase visible and near-infrared rotationally resolved spectra of the asteroid (223) Rosa as well as a rotationally combined median spectrum. (223) Rosa was confirmed to be an X-type asteroid under the Bus-DeMeo taxonomic system with a ~7.7%/𠜇m hemispherical variation caused by potential grain size or topological differences. Rosa's closest meteorite analog was found to be a weighted linear spectral mixture between 2 primitive meteorite types: a <125 𠜇m, relatively fresh sample of the meteorite Tagish Lake (10 %), and a 45-90 𠜇m sample of the meteorite Tarda (90 %) through chi-squared analysis. Similarities were found with both spectra, but albedo and density measurements favor Tagish Lake
MONITORING THE XANTHOPHYLL PIGMENT CYCLE IN EGG-LAYING HENS
Get PDFXanthophylls, oxidized carotenes, give some plants and animals their yellow pigmentation. In fowl, xanthophylls accumulate in the skin and egg yolks, with deposition influenced by the hen's egg production cycle and diet. This correlation makes pigmentation patterns a predictive tool for laying activity, allowing poultry producers to non-invasively monitor hen productivity. As hens lay eggs, xanthophylls deplete from pigmentation areas in a defined 30-week sequence. Bleaching occurs as xanthophylls transfer from a hen's skin to egg yolks. Bleaching begins at the vent, followed by the eye ring and earlobes (~15 eggs laid/3 weeks), the beak (15"“35 eggs/8 weeks), the bottom of the paws (65"“70 eggs/12 weeks), the shanks (155"“160 eggs/20 weeks), and concludes at the hocks and top of the toes (180 eggs/30 weeks). At peak egg production, full bleaching is observed, lasting ~52 weeks. Then, a 10-week molting period begins, during which egg production slows and pigmentation returns in the same order it was lost. Xanthophylls appear yellow due to their conjugated systems absorption properties. Visual inspection systems have been used extensively to assess yolk color, and high-performance liquid chromatography (HPLC) has been used to quantify carotenoids in blood and tissue samples. However, visual systems are subjective, and HPLC methods are invasive, requiring blood sampling or bird euthanasia. Raman spectroscopy is proposed as a non-invasive, in situ technique to quantify xanthophylls in hen's skin. Reflectance spectroscopy and corresponding established carotenoid quantification methods are also viable alternatives. Nutritional variability of xanthophyll intake affects deposition and thus potential quantification methods. A proposed two-point flock calibration scale addresses this by using the hens in a flock with the lowest (peak laying) and highest (end molting) pigment levels as endpoints on a scale that other hens would fall within. The proposed method would enable real-time monitoring of xanthophylls in live hens and assignment of hens to a specific stage in their productivity cycle
PARALLEL-KINETIC PERPENDICULAR-MOMENT SIMULATION OF MAGNETIC MIRROR PLASMA CONFINEMENT USING GKEYLL: EARLY TESTING OF A NEW COMPUTATIONAL MODEL
Get PDFAs demand for fusion power grows, increased focus has been placed on computational methods for simulating plasma dynamics in fusion reactor systems. This thesis tests a novel plasma simulation model currently being developed by researchers at the Princeton Plasma Physics Laboratory. In particular, this model was applied to a simple double Lorentzian magnetic mirror. Results were compared with currently favored gyrokinetic simulation models used in literature, showing rough agreement, however more research is needed to concretely verify accuracy. Computational performance was investigated, showing that this model has the potential outperform current gyrokinetic implementations once issues with parallelization and stability are addressed. Additionally, directions for future research with this model have been proposed