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Genomic structural variation in Barramundi Perch Lates calcarifer and potential roles in speciation and adaptation
No full textAdvancements in genome sequencing and assembly techniques have increased the documentation of structural variants in wild organisms. Of these variants, chromosomal inversions are especially prominent due to their large size and active recombination suppression between alternative homokaryotypes. This suppression enables the 2 forms of the inversion to be maintained and allows the preservation of locally adapted alleles. The Barramundi Perch (BP; Lates calcarifer) is a widespread species complex with 3 main genetic lineages located in the biogeographic regions of Australia and New Guinea (AUS + NG), Southeast Asia (SEA), and the Indian Subcontinent (IND). BP are typically considered to be a protandrous sequential hermaphrodite species that exhibits catadromy. Freshwater occupancy and intraspecific variation in life history (e.g. partially migratory populations) exist and provide opportunities for strongly divergent selection associated with, for example, salinity tolerance, swimming ability, and marine dispersal. Herein, we utilize genomic data generated from all 3 genetic lineages to identify and describe 3 polymorphic candidate chromosomal inversions. These candidate chromosomal inversions appear to be fixed for ancestral variants in the IND lineage and for inverted versions in the AUS + NG lineage and exhibit variation in all 3 inversions in the SEA lineage. BP have a diverse portfolio of life history options that includes migratory strategy as well as sexual system (i.e. hermaphroditism and gonochorism). We propose that the some of the life history variabilities observed in BP may be linked to inversions and, in doing so, we present genetic data that might be useful in enhancing aquaculture production and population management
Using targeted poisoning of red imported fire ants to improve Texas horned lizard habitat
No full textThe spread of red imported fire ants (Solenopsis invicta; RIFA) is often cited as a factor contributing to the decline of the Texas horned lizard (Phrynosoma cornutum; THL). Many studies have attempted broadcast poison application to eradicate RIFA; however, this could have unintended consequences for non-target invertebrates that THL need for food. Using a targeted application method, we sought to reduce RIFA abundance over the summers of 2022 and 2023 at Mason Mountain WMA in central Texas, a locality with an ongoing THL reintroduction program. At treated sites, one teaspoon of ant poison (Amdro®) was applied to bait stations with RIFA present thirty minutes after placement. Effects of each targeted poisoning were evaluated using pitfall traps and bait stations. Pitfall trapping was likely a more accurate estimate of ant abundance and revealed that targeted poisoning decreased RIFA abundance for both years and had variable effects on hatchling THL prey abundance
The effects of a four-week digital mindfulness intervention during a rowing task
No full textMindfulness can be defined as paying attention nonjudgmentally, in the present moment,
and being accepting of thoughts (Kabat-Zinn, 1994). Previous research has highlighted how
mindfulness can be used to build physical activity habits, namely through enjoyment of physical
activity, and utilizing associative attention during an exercise task which contradicts typical
thinking about enjoyment of exercise (Cox et al., 2018; Cox et al., 2020; Yang & Conroy, 2019).
The purpose of the current study was to examine if mainstream mindfulness delivered via
technology could be used to increase the enjoyment of exercise within an active population. A
total of 32 participants between 18 and 37 years of age (21.09 + 3.66) who met World Health
Organization (WHO) physical activity guidelines and had no previous experience with
mindfulness or meditation were included. Participants were either in the mindfulness
intervention (n = 17) or control condition (n = 15). Participants completed ten visits over four
weeks, each visit consisting of watching an episode of either Headspace Guide to Meditation or
Wild Babies on Netflix, followed by a 25-minute rowing task. Results found that the intervention
group exercised at a higher intensity and with associative attention, whereas the control group
exercised at a lower intensity, with dissociative attention, and all participants reported the same
rating of perceived exertion. The mindful exercisers experienced improved forecasted and
remembered pleasure from the intervention, indicating that they had better positive perceptions
of the exercise they completed, leading them to be more optimistic about their next exercise
bout. This research benefits exercise professionals to understand better how mindfulness can be
used to improve enjoyment of exercise, leading future research to investigate if the same results
can be found for inactive populations, who could use the intervention to create and sustain
exercise habits
Barriers and facilitators: The contrasting roles of media and technology in social¿emotional learning
No full textMedia and technology have come to play a ubiquitous role in children¿s lives. In response, researchers continue to explore the impact of media and technology on children¿s overall health and development. Since the COVID-19 pandemic, our paradigms have increasingly shifted from asking whether technology is influencing children¿s experiences to how technology is influencing child development. Accordingly, numerous studies using varied theoretical frameworks document how context, content, and amount of media and technology use influence children¿s social¿emotional skill development. This perspectives paper collates and synthesizes theoretical frameworks and empirical evidence relevant to children ages 0-12 years to address the question, ¿What are the ways, positive and negative, that media and technology use impact children¿s social and emotional learning (SEL)?¿ Our findings point toward opportunities to mitigate barriers and leverage facilitators to support children¿s social¿emotional learning and development as we progress into a technology-driven future
Comparative Analysis of Cemented vs Press-fit Fixation in Total Hip Arthroplasty
No full textResearch Question: In patients undergoing hip arthroplasty, does the restricted access of the Direct Anterior (DA) approach negatively impact the cementing technique compared to cemented arthroplasty with press-fit fixation, and does this cementing technique decrease the occurrence of loosening and fractures when compared to press-fit fixation utilizing the same surgical approach?Background and Significance: The purpose of this study was to use a combination of the direct anterior (DA) approach and the cemented replacement technique to achieve the functional benefits of the DA approach as well as the fixation benefits of cemented replacement. The limited access to the hip of the DA approach may have a negative impact on the cement technique. Additionally, does the use of such a cementing technique minimize the proportion of patients who experience difficulties that are not caused by cement?Materials and Methods: We conducted a retrospective analysis of 341 patients (360 hips) who underwent the DA total hip arthroplasty (THA) approach between 2016 and 2018. The total number of press-fit stems was 203, while the number of cemented stems was 157. The average age in the press-fit group was 75 years (ranging from 70 to 86), while in the cemented group it was 76 years (ranging from 52 to 94). Of the 341 patients, 239 individuals (70%) were females. The occurrence of femoral complications was compared between the two groups. The average duration of follow-up was 1.5 years (ranging from 0.1 to 4.4 years) for patients in the press-fit group, and 1.3 years (ranging from 0.0 to 3.9 years) for patients in the cemented group.Results: The press-fit group had a greater incidence of complications related to the femur (8 vs 0; p = 0.011). There were a total of two stems with failure of fixation and six instances of bone fractures, all of which necessitated further examination and correction. Fractures were observed at an average of 14.5 days (ranging from 2 to 31) after the surgery, while loosening occurred at 189 and 422 days after the surgery. The femoral cementing procedure can be safely performed using the DA approach, resulting in a lower incidence of complications compared to a contemporary series that does not involve the use of cement.Conclusion: Press-fit stems exhibited a greater incidence of early fractures and loosening. A similar rate of complication was not observed in our group of patients who received cemented stems. The process of cementing was successfully carried out using the DA approach without any complications. Femoral cementing during THA using the DA approach does not contribute
to surgical intricacy or duration, exhibits fewer initial femoral complications, and represents a safer alternative for elderly patients when compared to press-fit femoral arthroplasties
Risk Factors for False?Negative Covid?19 Testing in the Emergency Department: A Retrospective Cohort Study
No full textResearch Question: In adults who present to the emergency department for Covid?19 testing, what clinical characteristics are associated with false?negative Covid?19 test results?Background and Significance: Covid?19 has made enormous impacts on human health and society. Prior to Covid?19 vaccines and effective treatment strategies, medical and public health officials focused on reducing the morbidity and mortality of infections through early detection and social isolation. These strategies relied on dependable tests that could accurately confirm or exclude the disease. Early in the pandemic, important testing parameters were poorly understood. The lack of complete information on test accuracy had tremendous consequences. Covid?19 test results influence behavior, as those with a positive test result are more likely to socially isolate and cancel in?person plans, thereby limiting disease spread. Negative test results, however, often cause people to participate in their daily activities, like going to work or school inperson. False?negative Covid?19 test results can lead to devastating repercussions, as people with active Covid?19 infection may unknowingly infect others and to forgo other strategies to treat their own disease. The purpose of this study was to identify risk factors for potential false?negative Covid?19 tests. This information could be used to inform patient management, preserve limited resources, and educate patients to reduce the burden of Covid?19.Materials and Methods: This was a multi?center retrospective cohort study of patients who presented to the emergency department at one of 12 study hospitals in Texas, USA from June 1 to August 31, 2020 who were tested for Covid?19. Eligible patients received an initial negative Covid?19 test by reverse transcriptase chain reaction (RT?PCR), followed by a second, positive Covid?19 RT?PCR test within 30 days. We used Wilcoxon signed?rank testing (for categorical variables) and paired t?testing (for continuous variables) to examine clinical factors that were different between the first and second visits.Results: After screening 23,687 emergency department patient encounters, a total of 88 patients were included in the study. Patient?reported symptom duration was shorter for the first ED visit compared to the second (2.6 ¿ 0.3 days versus 3.6 ¿ 0.4 days, p?value=0.02). The findings from the first ED encounter that were most commonly associated with Covid?19 in our sample were increased lymphocyte count (35.2%), increased body temperature (32.6%), feeling nauseous (29.5%), and difficulty breathing (27.9%). Compared to the first visit to the ED, patients in our sample had differences in the second ED visit, which included the following: hypoxia (13.6% in the second visit versus 4.6% in the first, p?value: 0.005), abnormal infiltrates on chest radiography (59.7% in the second visit versus 25.9% in the first visit, p?value < 0.001), and elevated aspartate aminotransferase (29.1% in the second visit compared to 9.1% in the first visit, p?value <0.001).Conclusion: Healthcare providers in the emergency department should understand the factors that may be associated with false negative Covid?19 tests. In our analysis, the biggest factor was a short duration of symptoms (symptoms for less than 3 days). During this window period, the main clinical features were fever, nausea, and difficulty breathing. Additionally, laboratory investigations showing an increased white blood cell count, especially lymphocytes, was also associated with a false?negative result. This information could be used to guide patient management by re?testing in the ED, encouraging patients to re?test at home or another healthcare facility in 1?2 days, and urging patients to social distance while awaiting repeat testing and diagnostic confirmation
Synthesis and characterization of RPy2N2 pyridinophane ligands and transition metal complexes as therapeutics and catalysts
No full textThe pyridinophane family of macrocycles has been studied for decades as ligand
scaffolds for metals towards a wide variety of applications including biological mimics,
catalysts, and therapeutics A newer ligand scaffold to join the library, RPy2N2, introduces a
second pyridine ring to the long-standing PyN3 scaffold. This work explores the effect of 4
position modification of the two pyridine rings of RPy2N2 on the characteristics of the ligand
and the complexes of Cu(II) and Fe(III) for application as a SOD1 mimic and catalyst
respectively.
This work found that the modulation of the electronics of the 4-position substitution
tuned the electronics of the ligand overall, as evidenced in 1H NMR shifts and protonation
constants. This mirrored the trends seen with the 4-position substituted RPyN3 series, but
beyond that the exchange of one secondary nitrogen atom for a pyridine ring vastly changed
the behavior of the ligand scaffold, more than the electronics of the 4-position did. The pyridine
ring is less electron-rich than a secondary amine nitrogen atom, the effects of which can be
seen throughout the rest of this work.
When metalated with Cu(II), the RPy2N2 series vastly outperformed the previously
studied RPyN3 series as functional SOD1 mimics, resulting in the most active copper-based
small molecule functional SOD mimic to date. The electron-withdrawing groups improved the
activity, but the change in the ligand scaffold allowed for more drastic changes that greatly
increased the activity of the [CuII(RPy2N2)]2+ complexes as SOD1 mimics.
Similarly, the RPy2N2 ligand scaffold had such a great effect on the catalytic yields of
the complex formed in situ between FeIII(OTf)3 and RPy2N2, that no difference could be seen
between the different electronic substitutions. The ligand scaffold change increased the
catalytic yield to the maximum possible yield for the model reaction in use, an improvement
of at least 10% over the RPyN3 series. Additionally, it was seen that the RPy2N2 ligand series
is capable of forming two distict species in solution with Fe(III), posited to be the monomeric
and µ-oxo dimeric complexes, and that these complexes can interchange with each other with
simple pH control.
Altogether, this work focused on the functionalization of pyridine rings in RPy2N2
ligands and studying the effect of that functionalization on the activity of the ligands and the
metal complexes
Health?Related Quality of Life in Youth with Hypercholesterolemia
No full textResearch Question: Is the perceived quality of life different in youth <18 years?of?age with familial hypercholesterolemia (FH) compared to healthy peers?Background and Significance: In the U.S. and developed countries, cardiovascular disease (CVD) is the #1 cause of death in adults. Children with FH, a genetic disorder of dysregulated low?density lipoprotein cholesterol (LDL?C) metabolism, have the highest risk of developing premature CVD. Over the past 25 years, there has been an increased awareness of the need to assess and, whenever possible, optimize an individual¿s quality of life. This is particularly compelling in children, who encounter medical conditions during a vulnerable time of cognitive and emotional development. The Pediatric Quality of Life Inventory (PedsQL®) has been shown to reliably measure Health Related Quality of Life (HRQOL) in healthy youth, and in youth with a wide variety of medical conditions, such as obesity, congenital heart and kidney disease. The PedsQL® questionnaire is a comprehensive and multidimensional instrument capable of quantitating physical, emotional and social well?being, as well as school functioning. Completion of the PedsQL® is validated in both written and electronic formats, and several languages, including English and Spanish. While previous research has shown that youth with medical conditions often score significantly lower on the PedsQL® than their healthy peers, no prior studies have evaluated HRQOL in youth with FH.Materials and Methods: The PedsQL® 4.0 Generic Core Scales are multidimensional child self?report and parent proxy?report scales developed as the generic core measure to be integrated with the PedsQL® Disease?Specific Modules. The PedsQL® 4.0 Generic Core Scales consist of 23 items applicable for healthy school and community populations, as well as pediatric populations with acute and chronic health conditions. The scales measure physical, emotional, social, and school functioning. The R.E.A.C.H. (Risk Evaluation to Assess Cardiovascular Health) Clinic was established by Cook Children¿s Medical Center to better understand the cause(s) of premature CVD, including genetic and acquired forms of abnormal blood fats, elevated blood pressure, and weight?related health risks; developing effective means of prevention through health education, early detection of those at risk and timely treatment. The REACH clinic has a robust screening program, which has identified youth with FH. We compared the child self?report questionnaires of this population to published data of healthy peers.Results: Children with hypercholesterolemia demonstrated a significant difference in their perceived HRQOL compared healthy peers; and similar to children with chronic illness. Additionally, the average parent?proxy scores in children with hypercholesterolemia were lower when compared to a healthy population.Conclusion: Because the HRQOL assesses multidimensional well?being, an evaluation of these scores provide a comprehensive assessment of this vulnerable population. Although data are limited, an impaired HRQOL may be a risk factor for comorbid conditions. Furthermore, these data will help identify unmet needs beyond current recommendations for clinical care of youth with FH
AI Induced Anxiety: Analyzing the Effects of Prompt Engineering on Anxiety Levels
No full textThis study focused on AI induced anxiety, specifically how anxiety levels are affected when interacting with AI that employs prompt engineering techniques. Most of the research being done with AI is conducted to determine what prompt engineering techniques produce more accurate results, reduce hallucinations, and minimize misinformation. For that reason, it is necessary to study the effects of prompt engineering on users.
This research examined how prompt engineering, neuroticism, and contextual setting influence the user's anxiety levels in each AI interaction. I studied different prompt engineering techniques and language that affects interactions with neurotic individuals to determine the methods that would be most impactful in altering anxiety levels of neurotic individuals. To employ the prompt engineering techniques described in my hypotheses, I wrote custom code to assist with the generation of different prompts: each with different personas, contexts, and instructions that were then fed into an LLM to produce responses. Responses were then used in a survey of 996 TCU students to determine if anxiety levels changed based on the AI interaction.
Most of the hypotheses concerning the effects of different prompt engineering techniques on anxiety levels were supported; however, the vast majority of respondents, regardless of neuroticism levels, felt more anxious when faced with responses from bad prompt engineering techniques. This study concluded that neuroticism does not solely affect users' anxiety levels when interacting with AI, it revealed that prompt engineering techniques and contextual settings have a stronger influence over AI-anxiety than neuroticism. The next step would be to conduct research on the levels of anxiety normally felt with a human interaction in the same contexts as were used in this study's AI interaction to determine how influential AI is over anxiety levels
Associations Between Power Dynamics and Relationship Satisfaction in Couples Raising Autistic Children
No full textThe goal of this study was to examine the associations of marital satisfaction and power dynamics in couples raising autistic children compared to couples raising non-autistic children. Marital satisfaction is important to the longevity of a marriage, and the quality of a marriage can affect children's outcomes as well. Although prior research has established associations between power imbalances and low levels of marital satisfaction, there is no research examining these associations among parents raising children on the autism spectrum . To examine this question, couples with and without autistic children completed surveys and engaged in video recorded conflict discussions. The results indicated that wives raising autistic children reported significantly higher power than wives with non-autistic children at low and mean levels of satisfaction. Furthermore, levels of power observed during the conflict discussions were significantly associated with marital satisfaction. Using these results, it is important for clinicians to use therapeutic techniques that specifically target power imbalances in these couples and work to diminish them