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CHARACTERIZATION OF THE ROLE OF RSD-6, A TUDOR DOMAIN PROTEIN, IN ANTIVIRAL RNAI PATHWAY IN CAENORHABDITIS ELEGANS
No full textRNA interference (RNAi) triggered by virus produced dsRNA intermediate offers robust innate immunity against invading viruses in plants, insects and animals. Caenorhabditis elegans has been extensively used as a model organism to study host virus interaction. Recently, a forward genetic screen identified RNAi spreading deficient-6 (RSD-6), a Tudor domain protein, as a key component in antiviral RNAi pathway against Orsay virus in C. elegans but its contribution in the pathway remained unclear. Here, we generated a rsd-6 null allele using CRISPR-Cas9 genome editing, crossed it with other known RNAi mutants and analyzed Orsay virus replication in them and in combination with results from deep sequencing of small RNAs we show that abundant virus induced primary and secondary small RNAs are produced in rsd-6 mutant animals suggesting that RSD-6 acts downstream of secondary small RNA production in antiviral RNAi pathway in C. elegans. We also used various truncated versions of RSD-6 to rescue replication of FR1gfp in C. elegans and interestingly, our results show that Tudor domain of RSD-6 is not important in conferring antiviral RNAi in C. elegans. Finally, we show that the knock-down of RSD-6 in Caenorhabditis briggsae using feeding RNAi increases Santeuil virus replication suggesting that antiviral function RSD-6 is likely conserved among nematodes
THE INTERACTIVE EFFECTS OF STEREOTYPE ACTIVATION AND MINORITY GROUP BELONGING ON IDENTITY MOBILIZATION TACTICS, CAREER IDENTITY, AND LEADER IDENTITY FOR BLACK WOMEN IN THE WORKPLACE
Get PDFThe purpose of this study was to understand when and how Black women can achieve positive identity outcomes in the workplace when they experience stereotype activation. Despite Black women\u27s increasing presence in the workforce, they continue to face unique challenges at the intersection of race and gender, including negative stereotypes that undermine their credibility and limit career advancement opportunities. This research explored how Black women\u27s sense of belongingness to their minority group influences their use of identity mobilization tactics when stereotypes are activated, and how these factors collectively influence their career and leader identities.
Using a 2 × 2 between-groups experimental design, 262 Black women professionals were randomly assigned to conditions manipulating stereotype activation (high/low) and belongingness (high/low). While the experimental manipulations did not produce significant effects on the combined dependent variables, correlation analyses revealed significant positive relationships between identity mobilization and both leader identity (r = .262, p \u3c .001) and career identity (r = .347, p \u3c .001).
Exploratory analyses revealed a moderation effect of belongingness on the relationship between leader identity and identity mobilization, suggesting that Black women with lower levels of belongingness may rely more heavily on identity mobilization strategies as part of their leadership approach. Additionally, factorial ANOVAs on individual identity mobilization tactics suggested that bridging and challenging tactics may be more responsive to stereotype activation than other tactics.
These findings contribute to our understanding of how Black women navigate workplace dynamics through strategic identity management. They highlight the potential of identity mobilization as a resource for Black women to transform the challenges of their intersectional identities into professional advantages. This research offers insights for organizations seeking to create more inclusive environments and for Black women developing strategies to thrive professionally while maintaining authenticity
INTERNET-WIDE THREAT INTELLIGENCE AND ENTERPRISE LATERAL MOVEMENT DETECTION
No full textCyber threat actors, including state-sponsored groups and other malignant parties, pursue high-profile objectives aimed at fundamentally threatening national security. Their activities range from cyber espionage and data exfiltration to financial fraud, service disruption, botnet orchestration, and other malicious acts. Using established attack playbooks these attackers exploit vulnerabilities across the digital attack surface to infiltrate networks. A primary attack vector involves exploiting existing or emerging zero-day vulnerabilities within the public-facing applications. Once the network perimeter is breached, threat actors move laterally through systems, escalate privileges, and deploy backdoors to maintain persistent and stealthy access. This allows them to remain dormant like cyber sleeper cells akin to covert operatives in the intelligence community. Upon activations, these cyber cells are weaponized to execute targeted attacks within their exploitation scope or transformed into a distributed strike force that uses the victim’s infrastructure as cover to launch operations with near-perfect anonymity.
In this doctoral dissertation, we tackle these challenges using data-driven approaches focused on (i) analyzing diverse threat vectors targeting the digital attack surface of IT systems and (ii) inferring traces of lateral movement that compromise the network core. First, we address the pressing cybersecurity challenges at the Internet perimeter by operationalizing Cyber Threat Intelligence (CTI) from network telescopes extended with advanced deception techniques and coupled with UDP amplification and honeypot sensors. Our analyzed intelligence profiles concealed yet evolving cyberwarfare intentions amid global events, reveal nefarious activities unfolding in the wild, and uncover emerging vulnerabilities. This ultimately enable actionable insights to safeguard critical infrastructure and backbone systems. Second, we target the core of large and dynamic networks by analyzing authentication logs to uncover stealthy attack paths and malevolent activities. Our detection framework models networks as continuous-time dynamic graphs using a Temporal Graph Neural Network (TGNN)-based approach with inductive reasoning that enables the prediction of lateral movement paths even in incomplete or unseen network states. Such capabilities equip security analysts with tools to detect and triage covert network threats from cyber sleeper cells before escalation. Finally, this dissertation highlights the impact of its findings and lays the foundation for future research opportunities and directions
Revalidation of the Child Routines Questionnaire: Preschool
No full textThe implementation of consistent, structured routines is considered a positive parenting practice that enhances child development and is a protective factor for developing externalizing behavior problems, particularly for preschool-age children as they learn to regulate their behavior. In recent years, electronic media consumption has increased among children of all ages, and excessive use is related to negative outcomes for children. Thus, a measure assessing routines of preschool children with items related to electronic media routines is important to further understand how routines affect children’s emotional and behavioral regulation and their interactions with their parents. The purpose of the current study was to determine whether including items related to electronic media routines to items from the CRQ: P, a parent-report measure for assessing routines of preschool age children developed by Wittig (2005), would enhance the measure’s psychometric properties as well as its associations with children’s behavior problems and positive parenting practices. Participants included 203 adults (85.7% female; 85.2% white/Caucasian) with children between the ages of one and five. The results of an exploratory factor analysis resulted in two factors. The first factor included items pertaining to child-related routines in the home (e.g., sleep, mealtimes, and hygiene) as well as items related to positive parenting practices (e.g., developmentally appropriate activities, family interaction, and parents employing consistent household rules). The second factor included items pertaining to child-related responsibilities in the home, discipline, and items related to electronic media routines. In testing the validity of these factors, the first factor with items related to daily living routines for preschool children was positively associated with positive parenting practices and negatively associated with externalizing behavior. However, the second factor with items pertaining to electronic media routines was positively associated with externalizing behavior problems and negative parenting practices (i.e., inconsistent and punitive parenting practices). These results highlight the need to further investigate the construct of electronic media routines and identify strategies for including rules for their use that are associated with more positive parenting practices and fewer externalizing behavior problems
Quasistatic peridynamics, existence of unique solution in the presence of damage
Get PDFA mathematical model for damage propagation based on nonlocal potentials is developed within the framework of peridynamics. This model is applied to simulate damage evolution in cyclically loaded structures. By neglecting inertial effects, a well-posed quasistatic formulation for cyclic loading is obtained.\\ The resulting equation is expressed as a nonlocal and nonlinear integral operator that couples damage evolution to the deformation field.\\ This coupling occurs through the product of a damage factor and the derivative of a force potential. The damage factor ranges between zero and one, where one represents undamaged material and zero indicates complete damage.\\ It serves to reduce the internal force contribution as damage accumulates, making it well-suited for modeling fatigue behavior.
The existence of a unique solution to the quasistatic evolution along load paths is established under the assumption that the Fréchet derivative of the integral operator is invertible. Although invertibility is ensured when the displacement lies within the strength domain, we show that this requirement can be relaxed by identifying more general sufficient conditions. Building on this, an iterative method for bond breaking is developed using the Newton–Kantorovich theorem
TENSE AND AGREEMENT MEASURES IN YOUNG AFRICAN AMERICAN ENGLISH-SPEAKING CHILDREN
Get PDFThe Tense Marker Total (TMT) and the Tense and Agreement Productivity (TAP) score are two ways of measuring children’s tense and agreement systems, and studies have shown that both measures track developmental growth across different ages in General American English (GAE)-speaking children. This dissertation examined the feasibility and validity of using these measures for children learning African American English (AAE).
The data were cross-sectional archival language samples from 38 AAE-speaking children who ranged in age from three to five years (11 at 3 years, 12 at 4 years, 15 at 5 years). The language samples were coded and scored for TMT and TAP using GAE-based protocols from the original authors of these measures.
Results showed that the samples contained a sufficient number of obligatory contexts for calculating the two measures for all five morphemes for all the age groups except contexts for past tense -ed for the three-year olds. The AAE-speaking children earned TMT and TAP scores that were lower than scores reported for same age GAE-speaking children but they increased across ages similar to scores reported in the literature for GAE child speakers. Also, among the participants, copula BE emerged before the other structures, which was also similar to some previous studies of GAE-speaking children. The TMT and TAP had age effects between the 3- and 4-year-olds and 3- and 5-year-olds but no age effects between 4- and 5-year-olds after language sample length was controlled.
Finally, statistical analysis showed no association between the children’s Dialect-specific Form (DSF) Densities and their TMT and TAP scores. However, DSF Density was significantly higher in the 5-year-olds compared to both the 3-year-olds and 4-year-olds, which is unlike some previous studies of older children that show DSF Densities to decrease with age.
The findings support the use of TMT and TAP for measuring tense and agreement (T/A) in AAE. This supports the Disorder within Dialects framework that encourages the inclusion of T/A forms in assessment of children who speak non-GAE dialects of English such as AAE. However, the TMT and TAP scores for many participants in the current study showed typically developing (TD) cutoff scores lower than reported for same age GAE-speaking children reported in the literature. This indicates that the TMT and TAP measures as developed by GAE should not be considered as culturally appropriate for AAE-speaking children
Willingness to Accept to Reduce Animal Welfare by Removing the Ban on Caged Eggs in California, Massachusetts, and Nevada
No full textA recent outbreak of avian influenza increased egg prices nationwide. One combating proposal to reducing the cost of eggs is to remove the ban on caged eggs. However, it would decrease the welfare of laying hens. Using an incentive compatible elicitation, we investigate Willingness to Accept (WTA), a rarely examined concept in the context of animal welfare, defined as the level of savings required among consumers in California, Massachusetts, and Nevada to support the removal of the ban on caged eggs, potentially reducing animal welfare. We find the average WTA is 1.07, and $1.27 per dozen eggs (26.4%, 25.2%, and 27.7% of average reported price paid) in California, Massachusetts, and Nevada, respectively. It implies that shoppers from these states need a substantial decrease in egg prices to support the removal of the ban. Based on industry cost estimates, this required level of savings exceeds expected cost savings to farmers resulted from using cages, suggesting that the ban on cage-free eggs should be maintained in all three states
Designing a data collection and visualization toolkit for scalable tensor algebra in quantum chemistry applications
Get PDFLarge-scale quantum chemistry computations, such as those executed with the Tensor Algebra for Many-body Methods (TAMM) framework, require careful configuration of runtime parameters to achieve high performance and cost efficiency in high-performance computing (HPC) and cloud environments. Without effective performance analysis tools, researchers risk inefficient use of computational resources, leading to longer runtimes and higher costs.
To address this challenge, this thesis presents the design and implementation of a performance profiling and visualization toolkit for TAMM, developed as part of the DOE TEC4 project in collaboration with Pacific Northwest National Laboratory, Microsoft, and Louisiana State University. The toolkit collects detailed runtime data from TAMM-based quantum chemistry computations, enabling the analysis of tensor contraction performance, visualization of dependency graphs, and estimation of compute costs through machine learning models. A user-facing dashboard provides interactive performance views and supports optimization of configuration parameters such as tile size and node allocation.
The toolkit is evaluated using Coupled Cluster Singles and Double (CCSD) workloads on both LSU HPC systems and Microsoft Azure HPC cloud nodes. Results show that the machine learning models achieve accurate runtime prediction (Mean Absolute Percentage Error as low as 2.3% in certain test cases) and that the visual analytics effectively reveal performance bottlenecks. These capabilities make exascale-level simulations more accessible,interpretable, and resource-efficient for chemists and computational scientists
Twists of graded Poisson algebras and related properties
No full textWe introduce a Poisson version of the graded twist of a graded associative algebra and prove that every graded Poisson structure on a connected graded polynomial ring A:=k[x1,…,xn] is a graded twist of a unimodular Poisson structure on A, namely, if π is a graded Poisson structure on A, then π has a decomposition [Formula presented] where E is the Euler derivation, πunim is the unimodular graded Poisson structure on A corresponding to π, and m is the modular derivation of (A,π). This result is a generalization of the same one in the quadratic setting. The rigidity of graded twisting, PH1-minimality, and H-ozoneness are studied. As an application, we compute the Poisson cohomologies of the quadratic Poisson structures on the polynomial ring of three variables when the potential is irreducible, but not necessarily having an isolated singularity
Maximum spread of Ks,t-minor-free graphs
Get PDFThe spread of a graph G is the difference between the largest and smallest eigenvalue of the adjacency matrix of G. In this paper, we consider the family of graphs which contain no Ks,t-minor. We show that for any t ≥ s ≥ 2 and sufficiently large n, there is an integer ξt such that the extremal n-vertex Ks,t-minor-free graph attaining the maximum spread is the graph obtained by joining a graph L on (s −1) vertices to the disjoint union of (Formula Presented) copies of Kt and (Formula Presented) isolated vertices. Furthermore, we give an explicit formula for ξt and an explicit description for the graph (Formula Presented)