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Exposure to Phthalates and Replacements During Pregnancy in Association with Gestational Blood Pressure and Hypertensive Disorders of Pregnancy
Get PDFExposure to endocrine-disrupting chemicals such as phthalates may increase risk of hypertensive disorders of pregnancy (HDP). Prior studies lack investigation of chemical mixtures, phthalate replacements, or key periods of susceptibility including early pregnancy. In the present study, we used a longitudinal approach to evaluate gestational exposure to phthalates and replacements, as both single-pollutants and mixtures, in association with blood pressure and diagnosis of preeclampsia or any HDP. The Human Placenta and Phthalates prospective pregnancy cohort includes 291 participants recruited from two U.S. clinics. Urinary metabolites of ten phthalates and replacements were quantified at up to 8 time points per individual and averaged to create early (12–15 weeks) and overall (12–38 weeks) pregnancy exposure biomarkers. We collected data on gestational blood pressure (mean = 6.2 measures per participant) and diagnosis of preeclampsia (n = 26 cases) or any HDP (n = 44 cases). Linear mixed effects models estimated associations between exposure biomarkers and repeated blood pressure measures. We estimated exposure biomarker associations with preeclampsia and HDP using Cox proportional hazards or logistic regression models, respectively. Quantile g-computation was used to estimate joint effects of a phthalate or replacement mixture with each outcome. Early pregnancy exposure biomarkers demonstrated greater associations with adverse outcomes compared to overall pregnancy. A one-interquartile range increase in early pregnancy di-isononyl phthalate metabolites (ƩDiNP) was associated with a 1.13 mmHg (95 % confidence interval [CI]: 0.25, 2.37) and 0.90 mmHg (CI: 0.16, 1.65) increase in systolic and diastolic blood pressure, respectively. We also found positive but nonsignificant associations of early pregnancy mono-3-carboxypropyl phthalate, di-2-ethylhexyl terephthalate metabolites, and the high molecular weight phthalate mixture with blood pressure. Early pregnancy ƩDiNP was furthermore associated with increased odds of HDP (odds ratio: 1.37, CI: 1.03, 1.82), but not preeclampsia. In sum, early gestational exposure to DiNP and other high molecular weight phthalates may contribute to HDP
Wind Tunnel Testing of a Novel Quadrotor Design
Get PDFThis study presents the test development and aerodynamic evaluation of the Quadfoil UAV, a novel quadrotor configuration featuring a central lifting body in the form of an airfoil to enhance forward-flight efficiency. Flight tests conducted by Virginia Tech demonstrated a 25% increase in endurance and a 32% improvement in range compared to conventional quadcopters, validating the aerodynamic benefits of this design. To further investigate its performance, a dynamically adjustable angle of attack model support system was developed for wind tunnel testing, enabling precise replication of in-flight conditions. The support system, controlled via LabVIEW, adjusts angle of attack based on real-time tilt sensor feedback, facilitating force and moment testing across various speeds. Wind tunnel experiments included the identification of trim conditions as well as pitch sweeps without propellers, flow visualization, and power consumption measurements. The results not only validate the Quadfoil’s enhanced aerodynamic efficiency but also provide critical performance data, and power requirements, essential for refining flight control laws. These findings further establish the Quadfoil as a suitable solution for energy-efficient, long-range missions
Adjunctive Technologies to Electronic Fetal Monitoring: Promise, Pitfalls, and Lessons Learned
No full textDespite widespread use, electronic fetal monitoring (EFM) has not demonstrably reduced perinatal morbidity or mortality, and likely contributed to the rise in cesarean delivery. To improve its utility, a number of adjunctive approaches have been introduced over the past three decades, including fetal pulse oximetry, ST segment analysis (STAN), and maternal oxygen supplementation. Each intervention was supported by strong physiologic rationale, yet none achieved widespread clinical adoption due to inconsistent evidence of benefit and, in some cases, potential harm. This review critically evaluates landmark studies on EFM adjuncts, highlights the limitations that have impeded progress, and outlines emerging innovations, including artificial intelligence and multimodal surveillance. The persistent challenges in intrapartum fetal assessment underscore the need for high-quality evidence, rigorous implementation strategies, and a patient-centered reframing of EFM goals
Game Hacking & Anti-Cheat Analysis
No full textReverse engineering and analyzing game hacking and anti-cheat mechanisms is a complex and evolving field. This research document explores the history of game hacking, various techniques used in game hacking, and the countermeasures implemented by anti-cheat systems. Through case studies, we illustrate the strategies involved in creating cheats. Specifically, we demonstrate how to hack the open-source game AssaultCube using memory editing and code injection techniques available in Cheat Engine in a step-by-step manner so that the reader can theoretically reproduce the results shown in this paper. We also dissect the game’s anti-cheat mechanisms, identifying their strengths and weaknesses. This document aims to provide insights into the technical aspects of game security, highlighting the importance of robust anti-cheat measures in maintaining fair play in online gaming environments
Athletic Trainers\u27 Perspectives on Resources and Preparation Needed for Successful Salary Negotiation
No full textContext
Many athletic trainers (ATs) work under high stress, long hours, and low pay. These conditions often lead ATs and athletic training students to leave the profession. Previous studies show that over half of ATs do not negotiate salary, often because they feel the offer is fair or fear losing the job. Additional support is needed to help ATs prepare for negotiations, as current resources are limited.
Objective
This study explored ATs’ views on the resources need to prepare for salary negotiations during the hiring process.
Design
Consensual qualitative research.
Setting
Individual video interviews.
Patients or Other Participants
Twenty-eight participants from a prior study volunteered for qualitative follow-up (age = 37.8 ± 8.9 years; gender = 10 men, 17 women, 1 nonbinary; experience = 15.1 ± 8.3 years). Of the participants, 18 had previously negotiated salary and 10 had not.
Data Collection and Analysis
Participants were interviewed via individual video conference. Interviews were transcribed and data were analyzed into themes and categories following the consensual qualitative research approach. Member checks, multianalyst triangulation, and an external auditor were used to ensure trustworthiness of the findings.
Results
Two main themes emerged: desired resources and advice for others. Participants described resources they believed would be helpful for successfully negotiating salary and provided insight they believed could be helpful for others preparing to negotiate salary.
Conclusions
Both negotiators and nonnegotiators expressed a need for access to detailed data and continuing education on negotiation skills. Individuals entering a new employment opportunity should do their research before applying for the job and should understand the value they bring to a given place of employment
Behavioral Detection Methods for Automated MCP Server Vulnerability Assessment
No full textThe Model Context Protocol (MCP) has emerged as a critical standard for connecting AI agents to external data sources and tools. Still, its adoption has introduced significant security vulnerabilities across multiple attack surfaces. While recent research has catalogued extensive vulnerability taxonomies and attack implementations, automated detection methodologies remain limited. Current detection tools primarily employ static code analysis, which fails to identify behavioral vulnerabilities that only manifest during runtime server interactions. This study explores behavioral detection approaches for identifying MCP server vulnerabilities through systematic query-based testing, with particular emphasis on context manipulation techniques. Preliminary analysis of existing vulnerability research reveals 48 distinct attack types across four primary attack surfaces. The proposed methodology employs context-varied querying where identical requests are framed differently to expose inconsistent security behaviors. Using existing MCP security frameworks (MCPLIB and MCPSECBENCH), this research will evaluate the types of vulnerabilities that can be detected through behavioral analysis and assess the feasibility of automating these detection methods. This research addresses a critical gap in MCP security by developing systematic approaches to proactive vulnerability identification in deployed MCP server environments
Sara Ryan
No full textImage for Virginia Poets Databasehttps://digitalcommons.odu.edu/vapoets-images/1113/thumbnail.jp
Coming Back Differently: An Exploratory Case Study of Near Death Experiences of Webpages
No full textIn this case study, we use web archives to analyze 8,824 webpages that were taken offline and subsequently put back online, thus experiencing a “near death experience.” We enumerate the stages of a webpage’s near death experience, including the change from a successful HTTP status code to non-successful and back, the intermediate stage with markers such as an under construction banner, and an analysis of how the pages came back differently
The Interacting Roles of Attention Allocation and Trust in Highly Automated AAM Environments
No full text[First slide]
Mechanisms of attentive visual processing Attention control Visual search Eye movement Aging and individual differences
Limits of human performance in applied environment Complex displays Machine operation Surface transportation Advanced air mobility Nuclear operation
Methods to ameliorate human cognitive performance Human-machine interface Human autonomy/AI teaming Human-systems integration Trainin
Preservation of Genetic Diversity and Selection Over a Century in a Coral Reef Fish (\u3ci\u3eTaeniamia zosterophora\u3c/i\u3e) in the Philippines
No full textEvaluating the evolutionary impacts of anthropogenic activity on populations is key to understanding species resiliency and to designing effective conservation strategies. Sequencing DNA from historical specimens provides the opportunity to establish a historical baseline and empirically assess changes in genetic diversity, changes in effective population size, and selection over time. Here, we sequenced historical and contemporary samples of the cardinalfish Taeniamia zosterophora collected in 1908 and in 2021-2022 across two sites with differing human impact in the Philippines. At both sites, genetic diversity increased over time, with contemporary samples having significantly higher Watterson\u27s Θ than historical samples. This diversity increase was primarily attributable to positive selection on low-frequency alleles such that they increased toward intermediate frequencies through time. For the putatively neutral fraction of the genome, in contrast, there was a slight but significant decline in Watterson\u27s Θ at both low and high human impact sites, suggesting that drift strengthened and effective population sizes declined through time. There was more evidence for selection and greater loss of neutral diversity at the site with higher human impact. Our results provide empirical evidence for the surprising preservation of genetic diversity through the action of natural selection in the face of anthropogenic impacts