18525 research outputs found
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Photosensitive insecticides for mosquito control
No full textInsecticides reduce the spread of mosquito-borne disease. Over the past century, mosquito control has mostly relied on neurotoxic chemicals–such as pyrethroids, neonicotinoids, chlorinated hydrocarbons, carbamates and organophosphates–that target adults. However, their persistent use has selected for insecticide resistance. This has led to the application of progressively higher amounts of insecticides–known as the pesticide treadmill–and negative consequences for ecosystems. Comparatively less attention has been paid to larvae, even though larval death eliminates a mosquito’s potential to transmit disease and reproduce. Larvae have been targeted by source reduction, biological control, growth regulators and neurotoxins, but hurdles remain. Here, we review methods of mosquito control and argue that photoactive molecules that target larvae–called photosensitive insecticides or PSIs–are an environmentally friendly addition to our mosquitocidal arsenal. PSIs are ingested by larvae and produce reactive oxygen species (ROS) when activated by light. ROS then damage macromolecules resulting in larval death. PSIs are degraded by light, eliminating environmental accumulation. Moreover, PSIs only harm small translucent organisms, and their broad mechanism of action that relies on oxidative damage means that resistance is less likely to evolve. Therefore, PSIs are a promising alternative for controlling mosquitoes in an environmentally sustainable manner
Software tools to enable 3D bladder reconstruction from clinical white light cystoscopy videos
No full textBladder cancer is the tenth most common cancer in the world and has a 31-78% five-year recurrence rate. This high recurrence rate drives the need for individuals diagnosed with bladder cancer to receive cystoscopies every three months to one year for the rest of their lives. White light cystoscopies are the gold standard for diagnosis and follow-up in the bladder; during a cystoscopy, the clinician views the inside of the bladder with a camera passed through the urethra and into the bladder. Clinicians often use cystoscopy data to inform surgery and treatment; however, cystoscopy videos are cumbersome to review, so clinicians currently save a few notes and frames then discard the rest of the video. This video data can instead be saved in the form of a 3D bladder reconstruction, which preserves the texture and shape of the bladder in a form that is informative and convenient-to-review. Reconstructions, however, are inherently limited by the quality of their underlying data. This dissertation aims to improve reconstruction quality by improving the quality of the underlying video. We first improved reconstruction quality by removing a honeycomb-like artifact associated with equipment often used in clinical settings. Next, we developed a real-time pipeline to detect frames likely to inhibit reconstruction and give the clinician the opportunity to recollect the past few seconds of data. Finally, we developed a cystoscopy simulator to serve as a platform for testing and development of new clinical tools. In summary, this dissertation helps to improve reconstructions from clinical cystoscopies and aids development of future tools, which helps to enable the use of 3D bladder reconstructions in clinical settings to improve patient care
Predicting Mental Health Adverse Events from Clinical Notes – Can AI Make a Difference?
No full textPredicting mental health adverse events from clinical notes – can AI make a difference?
Ioana Danciu
Dissertation under the direction of Dr. Colin Walsh
Suicide is the third leading cause of death among young people aged 15-24 years old. In 2021 this age group experienced the highest statistically significant percentage increase among all other age groups. A plethora of information is contained in notes that is not well captured in structured data.
Natural language processing (NLP) using deep learning techniques intrinsically captures relationships between features, leading to models that more accurately represent the data. These models, belonging to a class of generically termed artificial intelligence (AI) methods, are very complex, with many parameters and are not immediately transparent to humans. To address these gaps, we developed predictive models of suicide attempts and adverse psychiatric outcomes using deep learning NLP methods and investigated the interpretability of these algorithms in three steps: First we created NLP models to predict mental health adverse events within 90 days of an emergency department (ED) stay using clinical notes. In step 2 we developed and evaluated a qualitative framework for model interpretability using expert-informed literature review and a survey instrument. Lastly, we developed and evaluated two commonly used interpretability visualizations. Our study found that models that predict suicide attempts and psychiatric adverse outcomes in a general population can perform above a threshold that justifies intervention. An AI model performance above a preset threshold is no guarantee this tool will be adopted and implemented in clinical care. As evidenced by the results of our survey, informaticians want to understand how AI models make recommendations. Previous experiences with AI tools, the types of risk involved, the degree of trust in the model’s prediction, the alignment with clinician’s assessment of the case all affect the utility of interpretable AI tools. The type of practice, the timing in providers’ workflows, and type of display also play a big role in adoption. Our results indicate that more work needs to be done to visualize AI model explanations in ways that fit into clinical workflows
Three Essays in Financial Economics and Economic History
No full textAmerica’s financial system has evolved through innovation, regulation, and economic shocks. This dissertation explores two economically important events, one historical and one modern, impacted the banking system. The first chapter analyzes banks' responses to labor market disruptions following the passage of Permanent Normal Trade Relations with China in 2000. Using call reports and local surveys of banks’ deposit footprints in various difference-in-difference regressions, I show that banks exposed to local labor market disruptions through their deposit bases faced asset quality and deposit supply shocks. Impacted banks reduced small business lending and increased mortgage securitization, especially outside their home markets. The second chapter examines the early impact of the Second Bank of the United States, a quasi-central bank chartered from 1816 to 1836, on state-chartered banks. The data show that public deposit withdrawals mandated by the Treasury weakened these banks and hindered later development. The final chapter digitizes late 18th-century postal road networks, revealing how their expansion fostered growth in banks and insurance firms. This chapter connects the growth of information networks with the expansion of firms reliant on information flows. Together, these essays demonstrate banks' vulnerability to funding shocks and the benefits of enhanced information dissemination
Creating Pediatric Mental Health Access in a School-Based Health Center
No full textSchool of Nursing Doctor of Nursing Practice Program ProjectPURPOSE:
This quality improvement project aimed to decrease the appointment wait time for a new mental health concern from two months or more to less than two weeks in 80% of children enrolled in an elementary school-based health center (SBHC).
METHODS:
This project analyzed wait times for a requested behavioral health (BH) appointment in the SBHCs from August 2023- December 2023 using a referral tracker. As children were referred, they were added to the tracker, and BH providers would initiate the appointments. When the BH providers schedules filled, a wait list would result, at which time the advanced practice nurses (APN) would then provide BH assessments for the children and create a BH plan.
RESULTS:
Of 112 children requesting a BH appointment at the SBHC during the project’s timeframe, 66.7% seen by an APN and 79.7% seen by a BH provider were assessed within 2 weeks. APRNs could fill an appointment request within an average of 19 days, while BH providers took an average of 18.6 days.
IMPLICATIONS FOR PRACTICE:
Results indicate that children can be seen faster in a SBHC than regional estimated averages for community BH providers.
Future studies can focus on determining exact averages for community wait times and analyzing an entire school year.
Additional considerations should explore a system for utilizing SBHCs to create BH access for pediatric primary care offices or the main hospital network
Staff Perceptions of Q15 Minute Patient Safety Observations in Inpatient Psychiatric Settings
No full textLicense accepted 05/07/2024Purpose:
While patient observations have been a mainstay for maintaining safety in behavioral health environments, little is known about how staff perceive the practice. The purpose of this project was to evaluate staff perceptions of every 15-minute patient safety observations in inpatient psychiatric units.
Methods:
A mixed-methods survey was developed that involved demographic questions, eight Likert-like questions, and three free response items. The survey was constructed within REDcap and distributed as a link in an email that was sent to all RN, BHS, and ABHS employees at Vanderbilt Psychiatric Hospital. Data were collected over 3 weeks.
Results:
Participants (n= 26) mostly had a bachelor’s (n=14) or master’s degree (n=11) and were mostly RNs (n=19). Nearly half of participants (n=12) reported 10+ years of experience. Participants expressed neutral to slightly agreeable views of Q15 minute observations. Overwhelmingly, participants agreed or strongly agreed that observations improve patient and unit safety (n=22 [84.6%]). Participants disagreed or strongly disagreed that observations negatively impact care quality (n=18 [69.2%]). Qualitative analysis resulted in the generation of “Promotion of Safety” as a major theme and “Harm reduction” and “Tailoring Patient Care” as subthemes for the purpose of observations. Respondents reported physically ensuring patient safety as an important aspect of safety checks and recognized poor quality task performance as a factor making checks unimportant. Suggestions for improvement included increasing the use of technology, increasing flexibility of checks, and selecting more observant staff.
Implications For Practice:
Behavioral health staff seem to have positive to neutral views of current Q15 minute safety observation practices and assert that observations promote safety. Staff support the idea of increasing technology supports to completing observations. Future research should focus on investigating ways to optimize and support current safety observation practices through uses of technological resources
Improving the Retention of First-Term Enlistees in the United States Marine Corps
No full textLeadership and Learning in Organizations capstone projectSuccessfully meeting its mission requires the United States Marine Corps to maintain a ready force composed of the correct mix of occupational specialties and military ranks. Currently, the Marine Corps lacks sufficient Marines in grades E-5 and E-6 to meet operational needs across the force. To test the organizational hypothesis that attrited Marines experience frequent buyer’s remorse, this study assessed perceptions, experiences, and affinity for service after the Marine has been separated for a year or longer using a newly developed survey instrument. The study yielded five central findings that informed four recommendations to the Marine Corps to improve retention, drive personnel satisfaction, and encourage interested attrited Marines to return to active duty service
Quantifying Microelectronics Reliability Under Cumulative Radiation Damage: Stress-Strength Inference with Type-I Censored Data for Failure Probability Estimation
No full textThe reliability of microelectronics in harsh environments is a vital yet difficult metric for engineers to quantify. While radiation-hardened parts may satisfy reliability requirements within space environments, other computational needs for the mission may suffer. As such, having a framework with which to analyze limited data from radiation tests on commercial off-the-shelf (COTS) parts is highly desirable. Such data may be limited due to the cost of performing the test or obtaining the part. Furthermore, as space has become more accessible to low-cost missions, risk aversion postures towards device qualification have given way to risk-acceptance out of necessity. With standard piece part hardness assurance methods, overconservative design margins and overtest requirements result in hefty testing requirements and arbitrary reliability metrics based on static environment models. In the ever-evolving landscape of space environment modeling, radiation hardness assurance has changed to accommodate new, probabilistic radiation models within an Earth-bound orbit by utilizing stress-strength statistics and confidence contours on the failure parameter space. In this thesis, a probabilistic radiation hardness assurance framework is presented which capitalizes on type-I censored data to bound failure probability estimates to desired confidence levels. By using type-I censored likelihood ratios, the failure distribution parameter space is bounded based on both failure and survivor data obtained during total dose part testing. By masking the failure probability space with the confidence contour and an upper parameter space bound, a worst-case failure probability can be obtained to the designated confidence level, even if failure data was not recorded before the conclusion of the part test. Examples are given using various orbits and part test data, and a comparison of standard hardness assurance techniques to the probabilistic method is provided
Calcium isotopes record changes in prior calcite precipitation (PCP) in coeval speleothems from Lake Shasta Caverns, CA during the Late Pleistocene.
No full textTraditional speleothem proxies, such as oxygen and carbon isotopes (δ18O, δ13C), and trace element to calcium ratios (i.e., Mg/Ca, Sr/Ca, P/Ca), can respond to multiple climatic and environmental processes, which often makes their signals challenging to interpret. Calcium isotope ratios (δ44/40Ca) are uniquely sensitive to a process called prior calcite precipitation (PCP). Two coeval δ44/40Ca speleothem records from Lake Shasta Caverns reveal dynamic changes in the amounts of PCP that occurred before speleothem precipitation, and these changes coincide with climatic shifts recorded during the Late Pleistocene. The δ44/40Ca records generated agree with traditional LSC speleothem proxy interpretations that indicate wetter-than-modern conditions during DO interstadials 2-7 and Heinrich Stadial 1 and drier-than-modern conditions during the Last Glacial Maximum. The similarity among the coeval δ44/40Ca records suggests that the same climatic and/or environmental processes influenced the preserved stalagmite signals, strengthening speleothem δ44/40Ca as a reliable hydroclimate proxy. The similarity between the LSC δ44/40Ca records with the LSC speleothem δ18O and δ13C records indicates that PCP influences these signals at LSC. Given that trace elemental ratios often serve as proxies for PCP, the lack of similarity between the δ44/40Ca records with the trace elemental ratio proxy records and monitoring data suggests that trace elements should be carefully evaluated as proxies for PCP in each cave system. The Rayleigh fractionation model allowed for the estimation of relative amounts of PCP preserved in the coeval speleothems. Many speleothem f values calculated were greater than 1, suggesting that δ44/40Ca may serve as a better proxy for aridity. Furthermore, calcium isotopes can be used to elucidate traditional speleothem proxies and show promise as a reliable hydroclimate speleothem proxy