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Diagnostic Utility of Tracheal Aspirate Cultures in the Neonatal Intensive Care Unit
No full textResearch Question: Are neonatal intensive care unit (NICU) clinicians accurately discriminating between infection and colonization of the upper respiratory tract based on results from endotracheal aspirate cultures (ETAs) of neonates in their evaluation of sepsis? Further, what are the qualitative results of these cultures and how are they related to the antimicrobial treatment method? We hypothesized that the results of the ETAs, regardless of colonization or infection, influence antimicrobial treatment of intubated neonates. The goal of this study is to determine the utility of ETA cultures in routine septic evaluations in the NICU.Background and Significance: Ventilatory?associated pneumonia (VAP) is a serious concern that entails high resource utilization in the NICU. Qualitative tracheal aspirate cultures are commonly utilized in VAP¿s diagnostic work?up. These cultures lack specificity for infection or pathology and have not been shown to differentiate between colonization and infection. The complex microbial community residing in the lungs has been proven to be important for the maintenance of homeostasis. This shift in view of the lungs as a site of colonization calls for new guidelines for interpreting positive ETAs, a routine part of a sepsis work?up in the NICU, and resultant treatment. This study will aid in outlining the microbial characteristics and current practices in treatment of positive ETAs.Materials and Methods: Using data obtained from tracheal aspirates from neonates, we classified patients based on the following: age, sex, EGA at birth, birth weight, EGA at time of culture, tracheal aspirate source, and simultaneous cultures. Cultures were detailed by organisms grown. Treatment was categorized based on the presence antibiotics used empirically at the time of culture, antibiotics used to treat any positive culture for greater than two days, and documented diagnosis. Surveying attending physicians at Cook Children¿s Medical Center, we have elucidated patterns of infection identification and antibiotic prescribing practices for intubated neonates. This was done using a questionnaire that automatically given to physicians of neonates with a positive ETA. The survey inquired about the physician¿s decision to obtain a tracheal culture, whether the results of the culture influenced treatment, their suspected diagnosis at the time of the culture and subsequent diagnosis 48 hours after the culture. The physicians were also asked to describe the factors used to distinguish colonization versus infection. Ultimately, the survey provides insight into determining if physicians¿ decision to treat positive cultures was in accordance with published guidelines and definitions of VAP and tracheitis.Results: We hypothesized that the tracheal aspirate cultures would be characterized by a variety of colonizing organisms and correlated antimicrobial treatment because of the ETA, regardless of diagnosis. More patients with positive ETAs were prescribed antibiotics due to this result than there were cases of true infection, and even those with suspected tracheal colonization.Conclusion: Physicians also overestimated the incidence of true infection, leading to additional unnecessary antibiotic use. It is imperative that the diagnostic utility of tracheal aspirate cultures be refined as antibiotic resistance continues to become more prevalent and the impact of unnecessary antibiotic use is not neutral for these patients and may have lasting effects
QUANTIFYING MULTI STAR SYSTEMS IN STELLAR GROUPS: CALIBRATION OF BINOCS FOR THE GAIA ERA USING SYNTHETIC PHOTOMETRY OF BP/RP SPECTRA
No full textPrecise assessment of binary star formation remains uncertain, yet it wields substantial influence on our understanding of galaxies' concealed dark matter. As it stands now, there are few methods to efficiently detect binary star systems in stellar groups, one of which is the Binary Information from Open Clusters Using Spectral Energy Distributions (BINOCS) fitting algorithm. With the launch of the European Space Agency Gaia spacecraft and its third data release, spectral data is more widely accessible for use. This project?s endeavor involves enhancing the BINOCS software with Gaia spectroscopic data, empowering the identification of binary stars among one million celestial entities. We modified the BINOCS software to perform online data collection, have a built-in Graphical User Interface (GUI), updated for Python3, and implement modern software engineering principles while retaining algorithm accuracy. The intention of this project serves as an interdisciplinary project between my major in computer science and minor in astronomy, where I can leverage my knowledge in computer science and apply it to a real-world problem
Longitudinal Study of Lexical-Semantic Organization as Measured by Repeated Word Associations in Children who are Deaf and Hard of Hearing
No full textLexical-semantic organization refers to the system of relationships between words and concepts that a child has in their vocabulary. Previous research shows that children who are deaf and hard of hearing (DHH) who use spoken language may have differences in their lexical-semantic organization systems as compared to their peers with typical hearing (TH). However, characterizations of the longitudinal development of lexical-semantic organization systems for children who are DHH compared to children with TH are unclear; the purpose of the present study is to investigate this development. The following research questions guided this paper: Between the ages of four and seven, do children who are DHH and children with TH differ in their growth in semantically-related responses? Between the ages of four and seven, do children who are DHH and children with TH differ in their growth in clang responses? Between the ages of four and seven, do children who are DHH and children with TH differ in their growth in taxonomically-related responses? Between the ages of four and seven, do children who are DHH and children with TH differ in their growth in paradigmatic responses? To answer these questions, results of the repeated word association task were analyzed. Results showed that both children who are DHH and children with TH increase their semantically-related responses over time, but children who are DHH respond, on average, with fewer semantically-related responses than their TH peers over the ages of four to seven. For clang responses, time predicts a decrease in responses for children who are DHH, but not for children with TH. No notable growth was found in the rate of taxonomic-related responses for neither group. Finally, time predicts an increase in paradigmatic responses for children who are DHH but not children with TH. Implications of the results are discussed
Evaluation of Exogenous Estrogen on IUI Success Rates
No full textResearch Question: The research question that drove our research was the following: What effect does estrogen supplementation during the ovulation cycle have on pregnancy outcomes compared to patients not receiving estrogen supplementation in women younger than 35 years of age and women aged 35-39 years who desired to conceive via IUI? By determining the effects of exogenous estrogen supplementation on pregnancy success rates, the utility of IUI may be increased as success rates may improve. This would further improve clinical pregnancy success rates for patients without cost acting as a significant burden.Background and Significance: Patients are often deterred from in vitro fertilization (IVF) for contraception assistance due to the cost and turn towards intrauterine insemination (IUI) before attempting IVF. However, for patients under the age of 35, IUI success rates are lower compared to IVF. It is hypothesized that this may be partly due to too thin of an endometrium. Data has demonstrated that a thin endometrial lining, defined as less than 7 mm, has less favorable outcomes in fertility treatments, especially with IVF. The effects of estrogen supplementation on pregnancy outcomes in relation to thin endometrial thickness have not been as thoroughly evaluated in IUI cycles. Additionally, the common practice of rescuing the endometrium with exogenous estrogen has not been adequately studied.Materials and Methods: 200 patients who underwent IUI between January 19 and September 22 were randomly selected from two categories: patients who utilized estrogen supplementation and controls (ie. no supplementation). Inclusion criteria included normal semen analysis (SA), two patent fallopian tubes, and patients under the age of 40 (stratified into <35 & 35-39). Exclusion criteria include male factor, defined as less than or equal to 5 million motile sperm, BMI greater than 35, smokers, and diminished ovarian reserve (DOR) defined by an anti-Mullerian hormone (AMH) level less than 1. Successful pregnancy was defined as a heartbeat detected (via vaginal ultrasound) at 6.5-7 weeks. For the experimental group, Estrace 2 mg was added (twice per day orally or once per day vaginally) at the initial ultrasound to start the fertility medications or at the follow up ultrasound during the treatment cycle to continue until a heartbeat was detected or a negative pregnancy test resulted. After assessing the normality of distribution of our data, we analyzed the data using an unpaired, two-sample t-test to determine whether estrogen supplementation improved the pregnancy rate associated with IUI.Results: While we initially anticipated that administering estrogen during an IUI cycle when the endometrium was considered thin would improve clinical pregnancy rates, this research surprisingly found that pregnancy rates were not impacted by exogenous estrogen.Conclusion: We understand that this is just one study and that we are limited by a small sample size. However, given the results of this research, it may be appropriate to discontinue the use of exogenous estrogen in this patient population. Continuing to utilize this treatment without success may prove fruitless and cost inefficient. This study should prompt additional research with greater sample sizes to further enhance the value of our findings, and if similar findings our discovered, standards should be updated to refrain from utilizing supplemental estrogen with the aspirations of improving clinical pregnancy rates from IUI
Photophysical Characterization and In Vitro Evaluation of a-Mangostin-Loaded HDL Mimetic Nano-Complex in LN-229 Glioblastoma Spheroid Model
No full textCytotoxic activity has been reported for the xanthone alpha-mangostin (AMN) against Glioblastoma multiforme (GBM), an aggressive malignant brain cancer with a poor prognosis. Recognizing that AMN's high degree of hydrophobicity is likely to limit its systemic administration, we formulated AMN using reconstituted high-density lipoprotein (rHDL) nanoparticles. The photophysical characteristics of the formulation, including fluorescence lifetime and steady-state anisotropy, indicated that AMN was successfully incorporated into the rHDL nanoparticles. To our knowledge, this is the first report on the fluorescent characteristics of AMN with an HDL-based drug carrier. Cytotoxicity studies in a 2D culture and 3D spheroid model of LN-229 GBM cells and normal human astrocytes showed an enhanced therapeutic index with the rHDL-AMN formulation compared to the unincorporated AMN and Temozolomide, a standard GBM chemotherapy agent. Furthermore, treatment with the rHDL-AMN facilitated a dose-dependent upregulation of autophagy and reactive oxygen species generation to a greater extent in LN-229 cells compared to astrocytes, indicating the reduced off-target toxicity of this novel formulation. These studies indicate the potential therapeutic benefits to GBM patients via selective targeting using the rHDL-AMN formulation
Potamological investigation into the fluvial terraces of the quaternary-to-modern Red River of the South: Canyon, Texas to Texarkana, Texas
No full textThe Upper Red River of the South has largely gone understudied by the scientific community. Tributaries and neighboring regions have been observed in some detail, but very little has been done on the Red River itself. In the course of this investigation, 13 discrete fluvial terraces were discovered within and above the Upper Red River Valley, providing a record that potentially spans to the Late Pliocene. Definitive dates spanning between the MIS 5c, some 0.1 Ma, and the Medieval Climatic Anomaly (MCA), 1 ka BP provide an avenue in which formational and degradational events can be assigned to specific climatic cycles, such as the Wisconsinan Glaciations, Last Glacial Maximum (LGM), and their interstadials, the Younger Dryas and its subsequent Collapse (CYD), and the MCA. Utilizing Optically Stimulated Luminescence (OSL) dating in conjunction with a hand auguring campaign, the terraces were drilled, logged, dated, and analyzed to determine architecture and characteristics of the fluvial deposits while pedogenic analysis allowed for the determination of the length of subaerial exposure to which these terraces were subject to prior to later burial. The dates for the terraces allowed for the further correlation of terrace construction, abandonment, and valley incision since the middle Sangamon Interglacial. These deposits record an ancient Red River vastly different to the stream seen today.
Thick assemblages of deposits and broad terraces reflecting a massive aggradational system suggest that this paleo-Red River was significantly larger. Relict deposits of the Lower Red River Valley confirm that the ancient River was similar in discharge and yield to the coeval Mississippi River, indicating that this ancestral Red River was a continent-scale river, thus suggesting a montane source to the west. In reconstructing a distribution model that connects the present Red River drainage basin to the Rocky Mountains, it is apparent that an additional fluvial axis would be required to nourish the ancient Red River. The Canadian River was identified through this study as being the ideal candidate for such a vector. However, this likewise suggests that the eventual pirating of the Canadian River by the Arkansas River became the Red’s downfall, as the Red River became both starved of sediment and discharge, relegating the former continent-scale River to the desert stream that rises atop the Llano Estacado today
Growing, learning, and connecting: Deciphering the complex relationship between government customer concentration and firm performance
No full textThe interplay between a firm's customer portfolio and the firm's performance presents a theoretical conundrum that challenges traditional supply chains. In particular, the role of government customer concentration-how extensively a firm incorporates government entities as part of its customer base-emerges as a pivotal factor with the potential to both bolster and burden firm performance. Analyzing 3,643 firm-year observations from the U.S. Federal Procurement Data System-Next Generation, Compustat, and FactSet Revere reveals an inverse U-shaped relationship between government customer concentration and firm performance. Excessive or insufficient government customer concentration adversely impacts performance, suggesting that a strategic balance is essential. Firm size, absorptive capacity, and network embeddedness are crucial in navigating this complex relationship, guiding a firm toward optimizing its government customer portfolio. This research advances the discourse on customer base management, underscoring the essential strategic considerations for firms interacting with government buyers
Room temperature phosphorescence: investigation into external perturbation of PVA film to enhance spin-orbit coupling
No full textIn this thesis, we present the Room Temperature Phosphorescence (RTP) of 4’-6-diamidino-2-phenylindole (DAPI) and Coumarin 106 (C106) embedded in PVA poly ((vinyl)alcohol) film, respectively.
Our previous studies concluded that chromophores are perturbed significantly enough to exhibit efficient phosphorescence emission when embedded into the PVA film. Furthermore, we observed that for some compounds embedded into the PVA film, we can observe direct triplet state excitation followed by strong phosphorescence emission. We also noticed that phosphorescence efficiency depends on PVA film preparation. So, we want to investigate modifications in PVA preparation/treatment and how the modifications may enhance Spin-Orbit Coupling (SOC). Our long-term project goal is to investigate if external conditions (conditions we can control/change externally, like electromagnetic fields) can affect SOC and lead to RTP emission in liquid solutions.
We found that an efficient room temperature phosphorescence (RTP) of DAPI has been observed with UV and blue light excitations. For C106, we also found an efficient RTP. We observed C106 directly excited phosphorescence at 465 nm, well outside the absorption band.
Then, we used C106 samples to study the effects of external modifications to the PVA treatments.
We found that the PVA polymer films change their optical properties after annealing at higher temperatures. Whereas the fluorescence intensity of C106 in PVA films modestly decreases with annealing, the phosphorescence depends dramatically and progressively increases by many folds. We believe this increase in the phosphorescence intensities results from increased intersystem crossing (ISC), which also decreases fluorescence. The phosphorescence lifetime decreases with annealing while the phosphorescence intensity increases.
We could not confirm the validity of investigating any external conditions that can affect SOC. However, we feel confident in our initial findings with annealing to say that it is possible to manipulate the PVA film preparation/treatment to enhance SOC
The Shape of Relations to Come: Multidimensional Analyses of Complex Human Behavior
No full textScience, understood to be the behavior of scientists, falls within the purview of behavior analysis. All scientists use scientific instruments to study a natural phenomenon, and for the behavior analyst, perhaps no tool is more important than the graph used to show changes in level, trend, and variability, and upon which behavior analysts make data-based decisions. Modern behaviorism as we know it dates back to the development of the cumulative recorder first developed in the 1930s. Though revolutionary to the science of behavior, two-dimensional graphs may be limited in application for analyzing complex human behavior. In the current article, we conceptualize verbal behavior as a multidimensional field of environmental relations, and introduce the use of multi-axial radar charts for its visual and quantitative analysis. From there, we survey the use of radar charts toward advancing a behavior-analytic understanding of human language and cognition. We demonstrate the use of radar charts for calculating simple shape descriptors as a quantitative measure of dynamic interactants, and show how they can be used to measure change over time
Investigating the Relationship Between Atopic Dermatitis and Irritable Bowel Syndrome
No full textResearch Question: In a cohort of patients with atopic dermatitis (AD), is there an increased prevalence of irritable bowel syndrome (IBS) compared to the general population and if so, what might be the contributing factors in this relationship?Background and Significance: AD is a chronic, recurrent inflammatory skin condition affecting 15-20% of children and 1-3% of adults worldwide.1 The hygiene hypothesis proposes that the rise in atopic disorders since the 1970s in developed countries is due to reduced “infectious pressure” from a Westernized lifestyle. Modern urban environments lack the microbial exposure which supports a diverse mucosal microbiome and promotes immunologic “priming.” For this reason, studies suggest a potential link between the microbiome and the development of atopic disorders, including asthma, allergic rhinitis, and AD. Although IBS affects an estimated 11.8% of the North American population2, the pathogenesis of IBS remains poorly understood. Evidence suggests a certain subtype of IBS may result from an imbalance in the microbial diversity in the gut, known as dysbiosis. Data strongly suggest that dysbiosis can signal an immune-related cascade in IBS. To our knowledge, no research has been done to evaluate the correlation between clinically diagnosed AD and IBS or the involvement of the microbiome in the development of both conditions. In this study, we investigated the relationship between IBS and AD in a cohort of subjects at board-certified dermatology offices. We also examined potential associations with selected covariates (e.g. demographic data, elements of past medical history, food intolerances) to further probe several secondary hypotheses.Materials and Methods: Participants over the age of 12 were recruited and consented based on inclusion criteria, including a clinical diagnosis of AD made by a board-certified dermatologist. Study participants were surveyed for the presence of IBS and IBS-related symptoms according to the Rome IV Criteria. They were also asked about other predictors and aspects of the past medical history.Results: The prevalence of IBS in our cohort of AD patients is 7.7%, compared to the estimated prevalence of IBS in the general population of 11.8%. However, we observed that a majority of individuals with AD experience regular abdominal discomfort (9/13, 69.2%) and food allergies, intolerances, and/or sensitivities (8/13, 61.5%). Among those with adult-onset AD, we observed all patients with adult-onset AD (3/3, 100%) also had lactose intolerance. Among those with childhood-onset AD, we observed 40% (4/10) patients also had nut allergies. There was no association with consumption of probiotic-rich foods or supplements, environment of upbringing, or mode of delivery at birth with the development of IBS in AD patients.Conclusion: There was no association between AD and IBS as hypothesized when compared to the prevalence of IBS in the general population. However, a majority of patients with AD in this cohort develop gastrointestinal symptoms on a regular basis and a majority also develop food allergies, intolerances, and/or sensitivities. The data also supports that lactose intolerance is associated with adult-onset AD, and nut allergies are associated with childhood-onset AD