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Lower pre-pulse inhibition in children with the 22q11 deletion syndrome
Full text linkObjective: The 22q11 deletion syndrome is associated with a range of possible physical anomalies, probable ongoing learning disabilities, and a specific constellation of neuropsychological deficits, including impairments in selective and executive visual attention, working memory, and sensorimotor functioning. It has been estimated that 25% of the children with 22q11 deletion syndrome go on to develop schizophrenia in late adolescence or adulthood. This is of urgent concern. Specification of early brain network vulnerabilities may provide a basis for early intervention while indicating critical links between genes and severe psychiatric illness. Neuropsychological studies of children with 22q11 deletion syndrome have implicated an array of potentially aberrant brain pathways. This study was conducted to determine whether preattentive processing (“sensorimotor gating”) deficits are present in this population. Method: The authors administered a test of prepulse inhibition to 25 children with 22q11 deletion syndrome and their 23 sibling comparison subjects, ages 6–13. It was predicted that the children with 22q11 deletion syndrome would have lower prepulse inhibition than the comparison subjects. Results: Prepulse inhibition in the children with 22q11 deletion syndrome (26.06%) was significantly less than that of the sibling comparison subjects (46.41%). Secondary analyses suggested that this decrement did not reflect developmental delay, and lower prepulse inhibition was associated with particular subsyndromal symptoms in some children. Conclusions: Sensorimotor gating is lower in children with 22q11 deletion syndrome. These findings may indicate specific brain circuits that are anomalous in 22q11 deletion syndrome
δ-Aminolevulinic Acid Dehydratase Single Nucleotide Polymorphism 2 and Peptide Transporter 2*2 Haplotype May Differentially Mediate Lead Exposure in Male Children
No full textChild low-level lead (Pb) exposure is an unresolved public health problem and an unaddressed child health disparity. Particularly in cases of low-level exposure, source removal can be impossible to accomplish, and the only practical strategy for reducing risk may be primary prevention. Genetic biomarkers of increased neurotoxic risk could help to identify small subgroups of children for early intervention. Previous studies have suggested that, by way of a distinct mechanism, d-aminolevulinic acid dehydratase single nucleotide polymorphism 2 (ALAD2) and/or peptide transporter 2*2 haplotype (hPEPT2*2) increase Pb blood burden in children. Studies have not yet examined whether sex mediates the effects of genotype on blood Pb burden. Also, previous studies have not included blood iron (Fe) level in their analyses. Blood and cheek cell samples were obtained from 306 minority children, ages 5.1 to 12.9 years. 208Pb and 56Fe levels were determined with inductively coupled plasma–mass spectrometry. General linear model analyses were used to examine differences in Pb blood burden by genotype and sex while controlling for blood Fe level. The sample geometric mean Pb level was 2.75 lg/dl. Pb blood burden was differentially higher in ALAD2 heterozygous boys and hPEPT2*2 homozygous boys. These results suggest that the effect of ALAD2 and hPEPT2*2 on Pb blood burden may be sexually dimorphic. ALAD2 and hPEPT2*2 may be novel biomarkers of health and mental health risks in male children exposed to low levels of Pb
Engaging with AI in a Technical Writing Course: A Collaboration between a Writing Instructor and a Librarian
No full textAfter describing our collaboration (a Technical Writing Instructor and a Librarian) on teaching students how to use artificial intelligence (AI) to strengthen their writing, we will engage attendees by having them reflect and practice with AI. For our workshop presentation, attendees will: Learn how a librarian and a writing instructor collaborated to teach students to use AI effectively and ethically in their writing. Reflect on how they can incorporate AI in their classroom or workplace. Learn how a librarian can help them incorporate AI into their courses. Practice using AI and developing their prompt engineering skills.
Our workshop presentation will be highly interactive and will show how AI in the writing classroom can enhance students\u27 communication, confidence, critical thinking, and problem-solving skills. Attendees will leave with ideas on how AI can be used effectively and ethically in writing. With a deeper understanding of AI-assisted writing, attendees will reflect on the advantages (and possible challenges) that come with using AI as writers and instructors
Yield Prediction Of PV Solar Energy Systems And Its Application In The Energy Grid For Operational Efficiency
No full textThe generation of power from photovoltaic (PV) solar panels is influenced by a multitude of factors. These include the tilt and orientation of the solar panels, the latitude of their location, and the prevailing climate and weather conditions. Additionally, shading at specific locations, particularly if the panels are not part of a solar facility, can significantly impact their efficiency. The quality and efficiency of the panels themselves, along with the preventive maintenance of both the solar panels and associated components such as inverters and trackers, are also critical. Finally, the overall system design and installation play a vital role in determining the power output. Understanding these factors and their influence is essential for accurately predicting the load that PV systems might impose on the grid and for maximizing their energy production. Independent studies are necessary to assess the dramatic effects of solar irradiance on production and its variance from the production specifications of the solar panels. This paper aims to examine various algorithmic approaches to better predict solar generation in the El Paso, Texas region and the Logan, Utah region, home to Utah State University. The data utilized in this study is sourced from the Texas Community Solar Facility, owned by El Paso Electric, and the Solar Car-Park located at Utah State University. To accurately predict solar generation and determine whether grid load needs to be alleviated with alternative resources or if energy should be sold at a higher rate, a comprehensive study of different predictive processes is conducted. This research is crucial as it can enhance grid stability and reliability, improve economic efficiency, and inform the development of more robust government policies with significant positive environmental impact
A Study Of Air Voids And Effective Air Voids In Hot Mix Asphalt (hma)
No full textAir voids are a fundamental parameter in the mix design of Hot Mix Asphalt (HMA), as they directly influence performance characteristics such as durability, permeability, and aging. Typically estimated using bulk and maximum specific gravity measurements, accurate determination of air voids is critical, given that laboratory samples are compacted to target void levels. This study investigates the influence of aggregate gradation and asphalt content on air voids, effective air voids, and specific gravity parameters - including bulk, apparent, and maximum specific gravities - in both fine- and coarse-graded HMA mixtures. Experimental testing included the determination of bulk, apparent, and maximum specific gravities, as well as performance metrics such as the Rutting Tolerance Index (RTIndex) and Cracking Tolerance Index (CTIndex). The findings reveal significant discrepancies between air voids calculated using different methods and effective air voids, with greater variability observed in coarse-graded mixes. Apparent specific gravity values exhibited considerable sample-to-sample variation, diverging notably from assumed generic maximum specific gravity values, thereby affecting the accuracy of air void estimations. A strong correlation was found between the ratio of effective air voids to total air voids. Given the demonstrated relationship between effective air voids and key durability indicators, this study recommends incorporating effective air voids into routine HMA mix design practices for improved performance prediction and quality control
Restoring Balance: Choctaw Policy And The Environment In New Spain\u27s Eighteenth-Century Frontier
No full textDuring the colonial period, Indigenous peoples in the Lower Mississippi Valley used their deep ecological knowledge to respond to imperial pressures. Eighteenth-century Louisiana was a contested borderland where Spain, France, and England vied for expansion through alliances, warfare, and trade with Native tribes. As European powers vied for control of the region, Native groups devised strategies to assert sovereignty over their territories and livelihoods. My dissertation examines the ecological history of the Choctaw and Spanish Louisiana from 1763 until the United States Indian Removal Act in the 1830s. It argues that imperial disputes over Indigenous lands compelled the Choctaw to restore balance to their symbolic and physical worlds. Central to this effort was Hina Hanta (the Bright Path), a sacred way of life that encompasses spiritual, cultural, and ecological relationships with the land. The environment was a key aspect of Choctaw diplomacy, influencing their alliances and negotiations with colonial powers. For example, seasonal cycles of hunting, farming, and trade shaped their engagement in diplomatic congresses and gift exchanges. This work demonstrates that ecological considerations were fundamental to Choctaw diplomacy and resistance. By examining Choctaw diplomacy through an environmental lens, my research highlights the centrality of Indigenous ecological knowledge in shaping power dynamics. To reconstruct this environmental history, I employ an interdisciplinary approach that integrates written sources - such as decrees, military correspondence, travel journals, and maps - with oral traditions, archaeological findings, and natural archives. Ultimately, this dissertation challenges the prevailing narrative that Indigenous diplomacy was primarily driven by trade. Instead, it demonstrates that environmental management was foundational to Choctaw strategies of survival, autonomy, and identity. By bridging imperial archives with Indigenous ecological frameworks, this study contributes to a deeper understanding of Native agency and resilience in colonial Louisiana, highlighting the enduring significance of Indigenous environmental knowledge in shaping historical power dynamics.
Keywords: Choctaw history, environmental history, frontier, borderlands, land management, Spanish Louisiana, tree-ring analysis, colonial archives, diplomacy
Advancing Additive Manufacturing For Extreme Environments Through Simulated Microgravity Printing
No full textAdditive Manufacturing (AM) holds significant potential for space exploration by enabling on-demand fabrication of components, reducing payload costs, and enhancing mission adaptability. However, microgravity introduces challenges in thermal regulation, material deposition, and structural integrity. This research explores the feasibility of submerged AM using neutral buoyancy in silicone oil to simulate microgravity conditions on Earth. A 3D printer was modified for submerged operation, with samples printed under three conditions: no oil (ambient air), submerged in oil, and simulated microgravity at varying temperatures. Mechanical tests, fracture surface analysis, and density measurements were performed to evaluate tensile strength, surface adhesion, and dimensional stability. Results indicate that air-printed samples exhibited superior layer adhesion and elongation, while submerged prints displayed quasi-brittle fracture due to rapid cooling in oil. Prints at 5 mm/s in oil showed improved bonding over 20 mm/s prints, attributed to extended heat exposure during deposition. Thermal analysis identified 100°C as the optimal oil temperature for submerged printing, minimizing warping and enhancing structural stability. This study demonstrates the potential of neutral buoyancy as an effective simulation method for space-based AM, revealing critical parameters for optimizing submerged printing. These findings contribute to the development of sustainable, in-situ manufacturing solutions for space missions