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Evaluation of the Effects of Raw Poultry and Cattle Manure Application in the Production of Bell Pepper and Radish Crops with Two Different Land Application Methods (Top Dressed or Incorporated in the Soil) on Productive, Soil Health, Fertility, and Food Safety Indicators
No full textThe use of biological soil amendments of animal origin (BSAAOs), such as raw poultry litter (PL) and cow manure (CM) is a common practice for improving soil fertility and crop productivity. However, the potential for microbial contamination raises concerns about food safety. This study evaluated the effects of PL, CM, and chemical fertilizer control on soil health, crop yields, and food safety risks in radish and bell pepper production over two years. Additionally, the impact of manure application methods (tilled vs. surface-applied) was assessed.
Field trials were conducted at the Louisiana State University Agricultural Center Burden Botanical Gardens using a completely randomized design with six treatment combinations: PL (tilled and surface-applied), CM (tilled and surface-applied), and a chemical fertilizer control (tilled and surface-applied). Soil and produce samples were analyzed for nutrient content, organic matter, pH, microbial contamination (Escherichia coli and total coliforms), and organisms die-off rates.
Results indicated that manure amendments increased soil phosphorus, potassium, and magnesium levels, with PL exhibiting higher nutrient retention but leading to soil pH declines over time. Short-term manure application did not significantly alter soil organic matter content. While BSAAO treatments did not significantly affect bell pepper yields, radish yields were notably higher in PL-treated plots, especially when tilled. However, excessive PL applications led to plant burning caused by high ammonia content in the manure. Bacterial wilt reduced bell pepper yields in the second year.
Microbial analysis revealed that radishes grown in PL-treated plots had higher E. coli levels than those in CM or control plots, indicating increased contamination risks. Bell peppers exhibited lower microbial contamination, and E. coli was undetectable after 13 weeks, supporting the USDA National Organic Program 90-day waiting period for trellised crops. While plastic mulch reduced E. coli risks, total coliforms persisted, suggesting additional mitigation strategies are needed.
This study highlights the need for optimized manure management practices that balance soil fertility benefits with mitigating food safety risks. Findings highlight the importance of application methods, environmental conditions, and regulatory compliance in ensuring sustainable and safe vegetable production systems
Four year practice effects on the RBANS in a longitudinal study of older adults
No full textObjective: The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) is a widely used measure in neuropsychological assessment. Studies of practice effects on the RBANS have typically been assessed over one or two repeated assessments. The aim of the current study is to examine practice effects across four-years after baseline in a longitudinal study of cognitively healthy older adults. Method: 453 Participants from the Louisiana Aging Brain Study (LABrainS) completed the RBANS Form A on up to four annual assessments after baseline. Practice effects were calculated using a modified participants-replacement method where scores of returnees are compared to the baseline scores of matched participants with additional adjustment for attrition effects. Results: Practice effects were observed primarily in the immediate memory, delayed memory, and total score indices. These index scores continued to increase with repeated assessments. Conclusions: These findings extend past work on the RBANS showing the susceptibility of memory measures to practice effects. Given that memory and total score indices of the RBANS have the most robust relationships with pathological cognitive decline, these findings raise concerns about the ability to recruit those at risk for decline from longitudinal studies using the same form of the RBANS for multiple years
Unique relations of avoidant, emotion, and problem focused coping and suicidality in a sample of sexual and gender minorities
No full textIndividuals who identify as a sexual or gender minority experience health related disparities in suicidal ideation, behavior, and attempts. Although past research has demonstrated that specific stressors may be unique to sexual or gender minorities contributing to suicidal ideation (e.g., minority stress), little work has been dedicated to understanding the role specific coping styles play in their associations with suicidal ideation among individuals who identify as a sexual or gender minority. The present study sought to address this gap in research and evaluate the unique associations of avoidant, emotional, and problem focused coping on suicidal ideation after accounting for theoretically relevant covariates. Participants included 372 individuals who identified as either a sexual or gender minority (Mage = 20.76, 83.3 % identified as female, 47.8 % White or Caucasian, 16.1 % Southeast Asian, 7.8 % Black or African American, 7.8 % multi-racial, 7 % other, 4.6 % East Asian, 2.7 % American Indian/ Alaska Native, 0.5 % Native Hawaiian or Other Pacific Islander). Results indicated that avoidant and emotional coping were associated with severity in suicidal ideation and suicidal cognitions, but avoidant coping was the only coping style that statistically significantly predicted greater likelihood of non-zero suicidal ideation/ cognition endorsement. Moreover, problem focused coping was the only style associated with less severe suicidal ideation and cognition. Overall, the present findings are the first to demonstrate unique associations of coping styles with suicidal ideation in the context of individuals who identify as a sexual or gender minority
Optical Spring Tracking for Enhancing Quantum-Limited Interferometers
Get PDFGravitational waves were first predicted by Albert Einstein in 1916. Calculations in the 1970s by Rainer Weiss showed an interferometer of sufficient size could realistically detect gravitational waves, which led to a grant by the National Science Foundation (NSF). With steady progress and over decades of funding by the NSF, the construction of two full scale 4km interferometers was approved and began construction in 1994. This project, coined LIGO the Laser Interferometer Gravitational-wave Observatory, came to be a worldwide collaboration of scientists dedicated to the discovery and study of gravitational waves. In 2015, both LIGO detectors detected a coincident inspiral waveform of two black holes originating 1.3 billion light years away, ushering in the era of gravitational wave astronomy. To maximize the number of gravitational wave detections, we desire the lowest noise in the frequency band which we would expect gravitational waves to appear. Two quantum effects increase the noise for LIGO, shot noise at high frequency and radiation pressure at low frequencies. The experiments throughout this dissertation seek to understand and mitigate this quantum noise within ground-based gravitational wave observatories such as LIGO.
As ground based detectors approach the standard quantum limit, it has become important to investigate techniques to reduce the total noise beyond this limit. Through the optical spring effect, these results demonstrate an interferometric configuration which has been shown to reduce noise below the standard quantum limit by 2.8 dB. This configuration when dynamically tracking a gravitational wave chirp, has also been shown to increase the SNR by up to a factor of 40. This work is presented alongside a passive power stabilization technique, demonstrating a maximum power suppression by a factor of 125. This technique provides a proof of principle how the laser power can be stabilized without the need for a pick-off and active feedback suppression, which may be useful for next generation detectors with higher input powers. Finally, evidence our system should be able to push the upper mass limit of measured macroscopic quantum effects is presented. This is shown though a phonon occupation measurement of 5.2 ± 0.3 in a nano-gram micro-resonator
Desire for death and risk of suicide: Covarying wish to die out of suicidal ideation
No full textQuantitative assessment of a patient\u27s perceived risk for suicidal behavior is commonly included in suicide risk screening and treatment monitoring. Although conceptually similar, no work has examined how one\u27s wish to die (WTD) relates to their perceived risk for suicide, or what constitutes one\u27s belief that suicide is possible beyond their WTD. In the current study, 1168 patients presenting across a hospital system with non-zero risk for suicide completed the Collaborative Assessment and Management of Suicidality-Brief Intervention (CAMS-BI). WTD was covaried out of the overall risk rating, and nonparametric correlations between the remaining residuals and theoretical and clinical risk factors were conducted. The residuals were significantly correlated with wish to live, constructs in theoretical models of suicide (e.g., psychological pain, self-hate), and multiple risk factors and warning signs such as past suicidal behavior, recent suicide planning, and impulsivity. This work highlights the distinct difference between one\u27s self-rated overall risk of suicide and their desire for death. Thus, clinical efforts must work beyond one\u27s desire to die to reduce a patient\u27s belief that suicide is possible in the future. Targeting factors correlated to perceived risk residuals once WTD was covaried such as self-hate, hopelessness, and wish to live may be fruitful
Effects of differential reinforcement and time-out on the unsafe playground behavior of young children
No full textThe purpose of this study was to examine the effects of differential reinforcement of other behavior (DRO) on reducing unsafe playground behavior of young children at school and subsequently, if necessary, the additive effects of a brief time-out. The DRO procedure was effective in eliminating unsafe behavior for one of four participants. The other three participants experienced the addition of a time-out procedure in combination with DRO. The DRO + TO condition nearly eliminated unsafe playground behavior for all three participants who experienced the condition. Additionally, the addition of time-out did not negatively affect social interactions among peers or self-reported recess enjoyment for any participant who experienced time-out. Following experience with all conditions, participants selected the condition they would experience via a concurrent-chains preference assessment. All three participants selected an intervention condition at every opportunity, and two of three participants selected DRO + TO most often
DEVELOPING AI MODELS FOR ANTIBIOTIC RESISTANCE GENE PREDICTION AND A CASE STUDY IN THE MISSISSIPPI RIVER
No full textAntibiotic resistance represents an escalating global health challenge driven by the overuse of antibiotics and the environmental dissemination of antibiotic-resistant bacteria and genes. Rivers act as key conduits and reservoirs for resistance dissemination, receiving continual inputs from wastewater effluents, agricultural runoff, and urban sources. This dissertation integrates a review of ARG detection methods with the development of artificial intelligence-based models for improved identification and classification of resistance genes, followed by an application to the Mississippi River.
Three machine learning frameworks, Trans-ARG, GNN-ARG, and ESM-ARG, were developed using transformer networks, graph neural architectures, and protein language model embeddings to capture structural and functional information within protein sequences. The ESM-ARG model, leveraging embeddings from Meta’s ESM-2, achieved higher predictive accuracy than existing models such as DeepARG, ARGNet, and ARG-SHINE. The framework was applied to metagenomic assemblies from the Mississippi River to assess the riverine resistome. Fewer than 1 percent of open reading frames (ORFs) were classified as ARGs, dominated by beta-lactam, aminoglycoside, multidrug and tetracycline resistance classes. Collectively, this research demonstrates that protein embedding-based deep learning substantially enhances ARG prediction and provides scalable, alignment-free tools for environmental resistome monitoring in complex aquatic ecosystems
Advancing Cell-free Systems for Production of Multiple Disulfide containing Proteins
No full textE. coli is widely used for recombinant protein production due to its rapid growth rate, simple cultivation, and genetic tractability. However, producing large (\u3e85 kDa) proteins with multiple disulfide bonds remains challenging. Endogenous oxidative folding enzymes in E. coli are often insufficient for eukaryotic protein synthesis and disulfide formation, which have more numerous and complex disulfide bonds than prokaryotic proteins. The CyDisCo system (cytoplasmic disulfide bond formation in E. coli), developed in 2011, enables efficient disulfide formation in E. coli using the catalysts human PDI and yeast Erv1p, producing high yields of proteins with up to 44 disulfide bonds. Despite this advancement, CyDisCo is most effective for smaller proteins, as larger disulfide-rich proteins remain difficult to produce. C-terminal agrin, a large proteoglycan containing 14 non-sequential disulfides, exemplifies this challenge. Agrin promotes CM proliferation and shows preclinical promise for heart regeneration; however, improving delivery to infarcted myocardium may enhance its therapeutic efficacy.
This work aims to develop a CFPS platform that can produce complex, disulfide-rich proteins such as agrin and engineer agrin for improved therapeutic outcomes for cardiac regeneration. Disulfide model proteins of increasing complexity (AppA, gLuc, BPTI, uPA, vtPA) were produced in CFPS supplemented with disulfide catalysts (DsbC/DsbA and PDI/Erv1p). PDI/Erv1p efficiently folded proteins with ≤5 disulfides, whereas proteins with ≥6 disulfides exhibited low solubility and activity. To address this, we developed autoinduced PDI/Erv1p-enriched extracts and combined CFPS with chaperone-rich (GroEL/GroES) extracts or an MBP fusion tag, increasing vtPA solubility and activity ~9.7-fold. Applying this optimized CFPS system to agrin yielded predominantly soluble disulfide-bonded protein. Initial results identified a region on agrin containing the EGF4 and LG3 domains as the cause of agrin insolubility; therefore, a truncated C-terminal construct lacking this region was produced in CFPS. Due to limited high-purity yields, commercial agrin (R&D Systems) was used for downstream testing. The PIGF-2123-144 [PJ1] peptide, with high affinity for ECM, was conjugated to agrin; ELISA results showed that PIGF-2123-144 conjugation significantly enhanced agrin binding to ECM.
This work establishes a simplified CFPS platform for producing large disulfide-rich proteins, better enabling the future development of therapeutic biomolecules. Additionally, PIGF-2123-144 mediated targeting of agrin to infarcted myocardium may enhance CM proliferation and improve functional regeneration
Identity And Arranged Marriage: Perspectives Of Potential Bengali Muslim Brides In Higher Education
No full textThis qualitative study examines how four single Bengali Muslim women pursuing doctoral degrees in STEM fields in the United States construct their identities as prospective brides within the arranged marriage process. While prior research has explored married women’s identities in higher education and women’s negotiations of singlehood, limited attention has been given to how unmarried Bengali Muslim women in higher education navigate searching for a partner while balancing career aspirations with social and religious expectations. Addressing this gap, the study focuses on four never-married Bengali Muslim doctoral students who are actively participating in arranged marriage negotiations.
Guided by Symbolic Interactionism as the theoretical framework and Interpretive Interactionism as the methodological approach, the study explores how meanings around marriage, singlehood, religion, and higher education are produced, negotiated, and revised through interaction. Data were collected through semi-structured interviews and participant-written open letters. In vivo and descriptive coding (Saldana, 2016) were used in a two-cycle analytic process, followed by cross-case analysis to identify shared patterns while honoring each woman’s situated narrative.
The findings of this research demonstrate that higher education operates as a powerful symbolic and material resource, providing participants with a voice, mobility, and a sense of strength and independence. All four women prioritize career and financial autonomy as non-negotiable while respecting the boundary of marriage as an institution. They also have been seen to resist cultural scripts that confine women to domestic roles or subordinate work to marriage. At the same time, strong family support, particularly from parents and siblings, emerges as a critical element that enables them to pursue advanced degrees and marriage delay despite social pressure.
Across cases, participants articulate fears of divorce, unequal power dynamics, and the fear of loss of educational and professional opportunities that fuel cautious and selective approaches to partner choice. All express a preference for educationally homogamous marriage, seeking spouses who match and share their educational level to some extent and share their religious and moral values, as a strategy to secure respect, equality, and mutual support. The study concludes that these women’s identity work is an ongoing, interactional process in which higher education, family relationships, and religious commitments intersect to reshape cultural expectations around gender, marriage, and Muslim womanhood
EFFECTS OF PHOTO-OXIDIZED CRUDE OIL ON GULF KILLIFISH EARLY LIFE STAGES
No full textPhoto-oxidation of spilled crude oil generates polar compounds that can heighten toxicity to marine fish embryos. We investigated the effects of photo-oxidized crude oil on early life stages of Gulf killifish (Fundulus grandis) by exposing embryos under flow-through conditions to water-accommodated fractions of four oil treatments: fresh oil unexposed to either sunlight or weathering referred to as dark control (DC), a UV-light oxidized whole oil (LT), the polar fraction extracted from LT (Pol) and the remnants after extracting the Pol from LT (NP). Oil loadings of 0.38–3.00 g oil/kg water were tested. Total PAH concentrations and chemical profiles of WAFs were determined via SPME-GC/MS, and embryo hatch success, heart rate, developmental abnormalities, and survival were monitored. Photo-oxidized WAFs (Pol and LT) yielded higher dissolved ΣPAH concentrations than non-oxidized oils (up to 4 times higher at 3 g/kg) after normalizing to carbon, although a Kruskal–Wallis test indicated no significant difference in ΣPAH among oil types at six hours after dilutions (p \u3e 0.25). Compositionally, Pol and LT WAFs were overwhelmingly dominated by oxygenated fluorenone derivatives (~95% of ΣPAH), whereas DC and NP WAFs contained mostly low molecular weight parent PAHs such as alkyl naphthalenes. Hatch success remained high (89–100%) in DC, NP, and LT exposures, but was significantly reduced in the 3g/kg Pol fraction (84%) compared to 98% in controls). This indicated that polar photoproducts primarily drove hatching failure. No significant effects on embryo survival, hatch rate or heart rate were observed in any oil treatment. However, embryos in the LT and Pol groups exhibited more frequent sublethal cardiotoxic effects and developmental abnormalities (e.g., pericardial edema, unlooped heart tube) than those in DC or NP. These findings demonstrate that UV-driven oxidation substantially alters the toxicity profile of crude oil by enriching PAHs that impair fish embryo development. The effects of photo-oxidation should therefore be incorporated into future environmental risk assessment studies