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Psychometrics of rating scales for externalizing disorders in Japanese outpatients
No full textObjectives This study validated the Japanese version of the Attention‐Deficit/Hyperactivity Disorder‐Rating Scale‐5 (ADHD‐RS‐5) and the Disruptive Behavior Disorders Rating Scale. We extended the ADHD‐RS‐5 by adding the oppositional defiant disorder and conduct disorder subscales to compare the two rating scales psychometrically. Methods We examined the internal consistency, test‐retest reliability, construct validity and criterion validity of the two rating scales in 135 Japanese outpatients aged 6–18 years. Results The internal consistency and test‐retest reliability were good for all the subscales of the two rating scales except for the conduct disorder subscale of the ADHD‐RS‐5 extended. Good construct validity was revealed by expected correlational patterns between subscales from the two rating scales and the Children Behavior Checklist. The criterion validity was good for all the subscales of the two rating scales rated by parents, while teacher‐ratings revealed substantially lower predictive ability for all the subscales. Agreement between parent‐ and teacher‐ratings of the two rating scales was generally moderate and using predictive ratings alone of both ratings showed the best predictive ability among the integration methods examined. Conclusion The two rating scales have sound psychometric properties and will aid in screening and severity assessment of externalizing disorders in Japanese clinical settings
Developing Al & Hf Based Hybrid Molecular and Atomic Layer Deposited Films for Low-k Etch Stop Applications
No full textModern devices, including calculators, sensors, and computers, rely heavily on integrated circuits (ICs). For the advancement of semiconductors in the modern era, progress entails shrinking the size of components within ICs to accommodate more elements in the same space. Nevertheless, this pursuit has encountered challenges, as reducing component dimensions has led to resistance and capacitance delays.This work primarily focuses on addressing capacitance delays, which are linked to dielectric constant and density of a material. To mitigate net capacitance delays in ICs, it is crucial to reduce the dielectric constant and density of etch stops and interlayers. Achieving this necessitates etch stops that can accommodate miniaturization of components while remaining chemically robust to decrease capacitance delays and sustain functionality. To tackle this challenge, there is a demand for new materials that yield in thin etch stops with low capacitance. Atomic layer deposition (ALD) and molecular layer deposition (MLD) are promising techniques for this purpose since they produce conformal thin films with precise control over thickness and conformality. ALD films form a continuous network of inorganic moieties while MLD films integrate organic components which impart tunability to the films. ALD and MLD can produce in-organic, organic hybrid films with tunable density and other parameters. MLD alucone films are created using trimethylaluminum (TMA) and ethylene glycol at 120 ºC, while hafnicone films are generated via MLD using tetrakis(dimethylamido) hafnium (TDMAH) and ethylene glycol at the same temperature. ALD alumina and hafnia films with terpineol inclusions are grown using TMA and TDMAH as metal precursors, water as an oxygen source, and Terpineol inserted between the metal precursor and water doses. The terpineol doped ALD films are grown at temperatures of 100 and 120 ºC. The as-deposited MLD and ALD films undergo annealing from 150-350 ºC in an inert vacuum environment. The thermal behavior of these hybrid films is studied through techniques such as FT-IR, in-situ XRR, in-situ XRD, spectroscopic ellipsometry, and capacitance-voltage and current-voltage measurements, and is compared against ALD films without organic inclusions. Ex-situ FT-IR confirms the incorporation and subsequent removal of organic elements in hybrid films during annealing. In-situ XRR measures changes in thickness and density of the hybrid films. MLD films exhibit significant decreases (80%) in thickness and density increases, surpassing terpineol doped ALD films (<40%) and plain ALD (<10%) films although the hybrid ALD, MLD films density is lower than ALD films after annealing at higher temperatures (800 ºC). The relatively smaller changes in density and thickness observed in terpineol doped ALD films are attributed to their higher structural stability. Notably, hafnium-based hybrid films display delayed crystallization compared to plain ALD films. Hf MLD films crystallize at 600 ºC, terpineol doped Hf ALD films at 450 ºC, while plain ALD films crystallize at 300-350 ºC. The dielectric constant of Al based hybrid ALD and MLD films, including terpineol, ranges from 3.5 to 6, whereas plain ALD alumina hovers around 6.5-7.5. Hybrid Hf based ALD and MLD films exhibit dielectric constants between 6-10, compared to plain ALD hafnia with a range of 10-14. When subjected to a CF4/O2 plasma, the etch rate of hybrid films is similar to that of plain ALD films (1 nm/min) after annealing at 350 ºC. These findings demonstrate that hybrid ALD and MLD films offer significant tunability, positioning them as potential candidates for low-k etch stop applications
The Evaluation of High School Mentorships and STEM Careers
No full textThis convergent mixed-methods study aimed to evaluate the mentorships in a high school with well-established student mentorship opportunities. Examining the characteristics and role of mentorships for students interested in Science, Technology, Engineering, and Math (STEM) careers determined how mentorships impact STEM career decisions. Quantitative analyses through binary logistic regression, chi-square tests, and independent t-tests uncovered characteristics of mentorship completers and completers interested in STEM careers. Completers were more likely to be female, did not have an Individualized Education Plan (IEP), were not enrolled in the Free and Reduced Lunch Program (FRLP), and finished more math and science courses than non-completers. Completers who expressed interest in STEM careers were more likely to be male, and finished more math and science courses compared to those who did not express interest in STEM careers. Qualitative data analyzed from 15 interviewees interested in STEM careers showed that completers were more likely to use resources, had greater career specificity, and had stronger STEM self-efficacy than non-completers.The results from this study can help STEM educators and school districts find methods to support students pursuing STEM careers. Potential mentorship program improvements included enhancing the accessibility and completion rate of student mentorships, enriching the meaningfulness of mentorship experiences, and simplifying the mentorship obtainment process. Implementing the changes above to mentorship programs aids in developing future STEM workers
Development of antibiotic-encapsulated Escherichia coli outer membrane vesicles as novel antibiotic agent to overcome resistance mechanism
No full textDevelopment of novel antimicrobial agents against Gram-negative bacteria is hindered by the intrinsic and acquired resistance mechanisms, such as the presence of dual membranes and downregulated expression of outer membrane porins to prevent drug entry into bacteria. Identifying a new method to improve delivery could therefore enhance the activity of existing antibiotics. We were inspired by outer membrane vesicles (OMVs), lipid nanoparticles actively released by Gram-negative bacteria, due to their capability to facilitate interspecies communication and genetic materialexchange among bacteria.With their demonstrated ability to deliver encapsulated content across bacterial membranes, we propose that OMVs can be used as nanocarriers for antibiotics to traverse the dual membranes of antibiotic-resistant Gram-negative bacteria. However, the ability for OMVs to encapsulate small drug molecules and the antibacterial efficacy of antibiotic-loaded OMVs (aOMVs) have yet to be explored. In this study, we focused on maximizing antibiotic encapsulation to facilitate successful and consistent aOMV synthesis and delivery to bacteria. OMVs were isolated from Escherichia coli JC8031, a hypervesiculating strain, using differential centrifugation and membrane separation. Fluoroquinolones were used to assess the antibiotic loading into OMVs, and the encapsulation efficiency was determined using UV-Vis spectroscopy. Four methods of loading were evaluated: passive loading, which included in vivo and in vitro non-destructive co-incubation approaches, and active loading, including sonication and electroporation. Our results show that active loading techniques resulted in a high encapsulation efficiency, with optimal loading observed with low voltage electroporation (200 and 400 V) and high consistency observed with sonication.The antimicrobial spectrum and bactericidal effectiveness of the aOMVs were then studied by treating laboratory and clinical antibiotic-resistant isolates of various bacterial species with the aOMVs. We observed that aOMVs can effectively inhibit the growth of both Gram-negative and Gram-positive bacteria, including multidrug resistant clinical isolates that acquired one or more resistance mechanisms. By comparing against free antibiotics at the same concentration, results reflected that aOMVs significantly lowered the bacterial population.We were further inspired to explore the mechanism of delivery for aOMVs. We chose to load aOMVs with imipenem and ciprofloxacin, the two antibiotics that utilize outer membrane proteins to gain entry into bacteria. aOMVs and free antibiotics were delivered to E. coli mutants with single-gene deletion and its wild type. Our results confirmed the essential pathway for the uptake of small hydrophilic antibiotics, and in the absence of the porin, aOMVs inhibited the growth of mutant more effectively than free antibiotics, indicating that aOMVs utilizes a porin-independent pathway while free-antibiotics are porin-dependent. In addition, we have provided insight into the intercorrelation between protein expressions. We have demonstrated that while some outer membrane proteins did not play an essential role in facilitating antibiotictransport across the outer membrane layer, the downregulation or the deletion of such proteins can affect the bacterial susceptibility.Together, these results demonstrated the potential of aOMVs as novel antibacterial agents to treat antibiotic-resistant bacterial infections. Furthermore, our study has contributed to the exploration and characterization of OMVs and their potential in drug delivery
How to Develop Data Science Projects for Production Deployments - Project Summary
No full textThe most common sources of user errors with data science models and how to prevent themThis project outlines the most common sources of errors users face with data science models, which includes when a model returns wrong outputs, varies output by release, crashes, misses the latest features, and doesn\u27t run in a new environment. Solutions to these issues are demonstrated with coding examples
Data-driven Advanced Computational Materials Modeling - Project Summary
No full textDeveloping scalable, interpretable AI tools integrating generative models to revolutionize computational materials discovery and enhance STEM education.This project addresses challenges in computational materials modeling by creating scalable, interpretable AI tools. Current machine learning (ML) models face high computational costs, difficulty handling complex crystal symmetries, and a "black box" nature that limits interpretability. To address these issues, we aim to integrate nonnegative matrix factorization (NMF) with generative AI. NMF offers structure-aware capabilities, reducing computational costs and incorporating material symmetries, while generative AI produces high-fidelity synthetic datasets to augment limited data. Additionally, uncertainty quantification is included to enhance model reliability. This hybrid approach aims to develop efficient tools for high-throughput materials discovery and property prediction. The project outcomes include scalable algorithms, enhanced interpretability for clearer insights into materials, and advanced methodologies for materials discovery. Open-source tools, user-friendly interfaces, and educational materials will ensure broader accessibility, supporting AI literacy and fostering collaboration. This effort benefits both Lehigh\u27s research community and broader STEM fields by advancing materials modeling and empowering diverse students through accessible AI tools and resources
Titanocene Redox Catalysis: A Sustainable System for Organic Radical Transformations
No full textTitanium (Ti) is non-toxic and is the second most abundant transition metal in the earth\u27s crustmaking it an attractive metal for the synthesis of inexpensive and environmentally friendly organotitanium
complexes. In the low valent form, Ti complexes have high reducing character and an open site to
coordinate to ligands and solvents, enabling inner-sphere single electron transfer processes. The most
common of these complexes is titanocene dichloride (Cp2TiCl2). Cp2TiCl2 has been implicated in a variety
of transformations involving epoxides and carbonyl functional groups with Cp2TiCl2 acting as a pre-catalyst
requiring the need for metal reductants to generate the active catalyst. In this dissertation mechanistic
investigations into the first application of titanocenes as photocatalyst in epoxide transformation that
avoids the necessity of stoichiometric metal reductants are detailed. The information obtained from the
mechanistic studies including the influence of amines, anions, light source, and hydrogen atom transfer
catalyst on the reactivity of the system was further probed to propose a mechanism for both reductive
arylation and cyclization of epoxides. Also, the development of a method for the synthesis of N-heterocycles by titanocene-mediated N-O bond cleavage in oxime substrates is described. This method,
while expanding the chemistry of titanocene redox catalysis, also addressed the challenges prevalent in
other systems that facilitated the formation of N-heterocycles via N-O bond cleavage in oximes.
Mechanistic insights into the mode of N-O bond cleavage and product formation are also detailed.
Furthermore, an overview of low-valent titanocene-induced bond weakening in small molecules through
coordination to the metal center is described. This insight is used to develop a titanocene-amine system
to facilitate proton-coupled electron transfer (PCET) transformations. These titanocene-amine complexes
are characterized using electrochemical and theoretical approaches and the associated bond dissociation
free energies (BDFE) of the various reactive intermediates are determined. The future direction of this
work is described including the potential application of the titanocene-amine system in dinitrogen
reduction.</p
Not So Unalterable: The Fluidity of Female Personhood
No full textThe complicated and connected modes of power relations which shape societal understandings of women have long been explicitly linked to traditional Victorian gender roles. Christina Rosetti\u27s "Goblin Market" has long been considered in terms of sexuality and gender, quite frequently in terms of queer sexuality of the two young women. Deemed a "textual crux for feminist critics" (Gilbert and Gubar 566), many have explained Rosetti\u27s work in light of a push against male authority. However, I argue "Goblin Market" reaffirms traditional gender roles by offering a parable of the dangers threatening young, single women: prostitution, the market, and the foreign.While many scholars have examined consumerism and sexual transgression in Victorian England, the aim of this paper is to examine the multiple and intersecting domains of power impacting the dynamic nature of social relations and gendered identities through the lens of Imani Perry\u27s concept of non-personhood, the foreign, and illness. I argue Christina Rosetti\u27s "Goblin Market" is a cautionary tale reinforcing proper gender roles for women in Victorian society, by establishing a socially constituted female biocitizen who is a wife and mother through economic and sexual threats. By framing the poem as a narrative told by the women to their children, there is an emphasis on the importance of storytelling in the crafting of cultural identities. </p