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Simultaneous Emergent Phenomena: Leadership and Team Synchrony
No full textEmergent phenomena exhibit interesting dynamics when considered individually. The present article examines two emergent processes that could be occurring simultaneously in an intense team interaction: the emergence of leaders and the emergence of autonomic synchrony within teams making dynamic decisions. In the framework of panarchy theory and related studies on complex systems, autonomic synchrony would be a fast dynamic that is shaped or controlled by leadership emergence, which is a slower dynamic. The present study outlines three distinct statistical distributions—the swallowtail catastrophe model for phase shifts, inverse power laws that indicate fractal processes, and lognormal distributions—that are known to characterize emergent processes of different types. The objective was to determine the extent to which the two emergent processes reflected the same dynamics. Research participants were 136 undergraduates who were organized into teams of three to five members playing the computer-game Counter-Strike while wearing GSR sensors to measure autonomic arousal levels in a steady stream. After approximately two hours of interaction, team members rated each other on leadership behaviors. Autonomic synchrony was analyzed as a driver-empath process that produced individual driver scores (the total influence of one person on the rest of the group) and empath scores (the total influence of the group on one person). Results showed that leadership emergence displayed the swallowtail configuration that was consistent with prior studies. Autonomic synchrony started as a simpler process and unfolded into a swallowtail catastrophe toward the end of the experimental session. Lognormal distributions were second-best representations of all variables. Inverse power laws were least descriptive of any of the research variables. The implications of the temporal dynamics of the co-emerging processes for training and team development are discussed
From AI Chatbot to Brand Support: An Exploration of Perceived Empathy and Ethics in Shaping Trust and Word of Mouth
No full textRecent technological advancements have significantly enhanced AI chatbots’ ability to engage in meaningful conversations and empathic interactions, creating new opportunities for human-AI interaction while also introducing ethical considerations. This study surveyed 789 U.S. users of AI chatbots to examine how their perceptions of empathy and ethics in these chatbots influence trust in the company. The results show that perceived empathy and ethics are strongly linked to users’ trust in the company, which, in turn, affects their intention to continue using the chatbots and their likelihood of providing positive word of mouth. This study highlights the importance of empathy and ethics in AI chatbot usage from the end user’s perspective, with both theoretical and practical implications discussed
ASSESSING THE RELATIONSHIP OF CULTURAL VALUES, AND NEIGHBORHOOD FACTORS IN PRENATAL DEPRESSION AMONGST MEXICAN WOMEN
Get PDFMaternal depression during the perinatal period is a debilitating illness which negatively influences maternal health, child development and family functioning. The rate of maternal depression in Mexican-American mothers is substantially higher than non-Hispanic white populations. Some work has linked maternal depression in the US Mexican population to cultural factors and neighborhood dynamics, but these factors are only beginning to be addressed in perinatal mental health. This study investigates the independent and interactive roles of cultural values and neighborhood factors in predicting perinatal maternal depressive symptoms in women of Mexican descent. The study recruited pregnant women (N= 261) of Mexican descent in Southern California. Depressive symptoms were measured at early, mid and late pregnancy (15-17, 25-27 and 33-35 weeks’ gestation; respectively), using the Center for Epidemiologic Studies Depression Scale (CES-D). Cultural values (familismo and respeto) were assessed in early pregnancy using the Mexican American Cultural Values Scales (MACVS). Neighborhood factors, including systemic neighborhood factors (Area Deprivation Index—ADI), perceived neighborhood quality (Neighborhood Quality Evaluation Scale—NQES), and social cohesion (Neighborhood Environment Questionnaire—NEQ), were evaluated at mid-pregnancy. Linear mixed-effects models analyzed the effect of cultural values and neighborhood factors on depressive symptom trajectories over pregnancy, and moderation analyses tested the interaction effects of cultural values and neighborhood factors on depressive symptoms during mid-pregnancy. The findings showed that higher adherence to the cultural value of respeto was significantly associated with a decrease in depressive symptoms across pregnancy. While familismo alone did not have a significant main effect on depressive symptoms, it moderated the relationship between perceived sense of safety and depressive symptoms during mid-pregnancy, such that lower perceived safety significantly predicted higher depressive symptoms at mean and high levels of familismo. Furthermore, individual perceptions of lower sense of safety and lower social cohesion were associated with increased depressive symptoms over pregnancy, but the systemic measure of neighborhood disadvantage (ADI) did not significantly predict the trajectory of depressive symptoms. The study highlights the importance of cultural values and individual perceptions of the neighborhood environment in understanding perinatal depression among women of Mexican descent
Cardiac and Coronary Hemodynamics: Using an Integrated Ex-vivo Beating Heart Experiments and Computational Modeling
Get PDFCardiovascular function arises from the complex interactions among the heart, the arterial system, and the coronary circulation. Questions such as how variations in left ventricular (LV) loading conditions affect LV and aortic functions through LV–aorta interactions; and how coronary artery diseases, such as stenosis, impact cardiac function and myocardial perfusion including left and right coronary perfusion via LV–coronary interactions, remain understudied. To answer these questions, this thesis focuses on two core objectives: (1) investigate the effects of LV loading conditions on LV and aortic functions through LV–aortic interactions by performing ex-vivo beating rat heart experiments, and (2) elucidate the impact of coronary artery stenosis on coronary perfusion in the left and right coronary arteries (LCA and RCA) by developing a Distributive Model and a one-dimensional Navier-Stokes Model. Understanding LV–aorta interaction is essential for revealing how alterations in preload and afterload affect cardiac output and hemodynamic efficiency. To investigate these interactions, we conducted ex-vivo beating heart experiments that allowed independent modulation of preload and afterload to quantify their effects on LV and aortic functions. In the ex-vivo beating heart experiments, LV and aortic functions including LV pressure and volume waveforms, aortic pressure waveforms, aortic flow rate, were measured by independently varying LV preload and afterload. Our results demonstrated that increased afterload led to reduced aortic flow and elevated LV developed pressure (DP), whereas increased preload enhanced aortic flow and was accompanied by a rise in DP. These findings indicate that aortic pressure predominantly governs aortic flow under varying afterload conditions, whereas LV DP plays a dominant role in regulating aortic flow under different preload conditions. In parallel, a Distributive Model and a one-dimensional Navier-Stokes Model were developed to investigate cardiac–coronary interactions, focusing on how coronary artery stenosis impacts myocardial perfusion, in both LCA and RCA. Specifically, a one-dimensional Distributive Model and Navier–Stokes Model, incorporating anatomical LCA and RCA networks, vessel compliance, and fractional flow reserve (FFR), were developed to simulate coronary functions and regional perfusion under varying degrees of stenosis in a closed-loop of systemic circulation. The model predicts that as stenosis severity increased, coronary flow decreased significantly in both the LCA and RCA, demonstrating the nonlinear nature of hemodynamic impairment. Notably, coronary flow reduction in the RCA is more pronounced than that in the LCA, indicating a vessel-specific susceptibility to stenotic effects. These results highlight two key findings: (1) stenosis severity exerts a nonlinear impact on coronary pressure and flow, and (2) the RCA exhibits greater perfusion loss compared to the LCA under equivalent levels of stenotic conditions. Together, the ex-vivo beating heart experiments not only demonstrate mechanistic insights into how ventricular loading and aortic properties collectively shape cardiovascular function but also provide valuable information for computational modeling (e.g., measured hemodynamics serve as boundary conditions and reconstructed contractility-flow relationship) and rigorous model validation. The developed computational modeling can predict detailed hemodynamics in coronary vessels and elucidates how ventricular loading and coronary artery stenosis influence myocardial perfusion and overall cardiovascular performance, which is difficult to measure in experiments, overcoming the limitations in pure experimental studies. These findings have important implications for advancing the diagnosis, monitoring, and management of cardiovascular diseases such as heart failure, aortic stenosis, and coronary artery disease. The developed integrated experimental and computational tools can be applied to understand the underlying mechanisms of a wide range of cardiovascular diseases in future
Leaning on Experience: First-Generation Faculty as Institutional Agents
No full textFirst-generation faculty (FGF), who were the first in their families to graduate from college, are often hailed as resources for first-generation students. Despite a wealth of narratives written by FGF, limited systematic empirical inquiry investigates if FGF pursue student success and how. Drawing on open-ended interviews with a racially diverse, purposeful sample of FGF employed in the United States (n = 19), this narrative analysis leverages Stanton-Salazar’s institutional agent framework to explore how, if at all, FGF employ their experiences and resources on behalf of students, particularly those from marginalized backgrounds. I found that these FGF enact agentic strategies that rely on one-on-one interactions with students (i.e., direct support, interpersonal engagement, and instructional support), which manifested in three primary ways: (a) philosophical belief in the inherent link between teaching and mentorship; (b) strategic and authentic disclosure of their identities, backgrounds, and challenges; and (c) facilitating success by “demystifying” the academy. The influence of first-generation status was evident throughout. This study demonstrates the significance of shared background between institutional agents and students, extends previous scholarship on faculty’s unique role in student success, and underscores the value of storying as an agentic tool—all related to a population that receives limited scholarly attention. Although FGF can meaningfully leverage shared experience to influence student success, colleges and universities must assume responsibility for interrupting and eradicating the obstacles the academy presents to first-generation students and FGF. Given the diversity among FGF, future research should investigate variation by social identity in student success dispositions and approaches
Physiology of Ageing Skeletal Muscle and the Protective Effects of Exercise
No full textIn 2020, the United Nations (UN) General Assembly declared 2021–2030 the ‘Decade of Healthy Ageing’, a global collaborative call to action for governments, clinicians, scientists and society to work together to improve the lives of the ageing population. One important area of scientific inquiry for this initiative is understanding why advancing age leads to a progressive loss of skeletal muscle mass (sarcopenia) and function (strength and power). This is a critically important problem because skeletal muscle health is not only essential for maintaining the mobility and physical function required for independent living but is also important for systemic health. For example, skeletal muscle helps with the regulation of glucose metabolism and insulin resistance and maintains the plasma amino acid concentrations necessary for hepatic gluconeogenesis and tissue regeneration and repair in response to injury and disease. While the importance to society is eminently clear, the physio-logical mechanisms underlying the ageing skeletal muscle phenotype remain poorly understood
Frequency-Dependent Assembly Processes Determine the Coexistence and Relative Abundance of Tropical Plant Species
Get PDFTesting the extent to which ecological communities are structured by deterministic (niche-based) assembly processes, resulting in predictable species abundance and composition, is a fundamental goal of ecology. Here we use a 10-year dataset of 55,156 lianas comprising 86 species in an old-growth tropical forest in Panama to test whether community assembly is consistent with niche-based assembly processes. We find that species diversity and community composition was maintained because species conformed to four general requirements of coexistence theory: (1) species have negative conspecific frequency-dependent feedback that control their local population size; (2) species have a stronger negative effect on their own population than that of heterospecifics; (3) the equilibrium frequencies of species correspond to their relative abundance; and (4) species have positive invasibility. These results indicate that coexistence through deterministic niche-based processes controls local population sizes and prevents any one species from displacing others. Rare species persisted because particularly strong negative feedbacks maintained them at their relatively low equilibrium abundances, thus preventing them from going extinct. Furthermore, we show that it is necessary to use population demography to test coexistence theory because stem mortality alone does not reflect species demography. These findings have broad implications for species coexistence and diversity maintenance in tropical forests and possibly other ecosystems
Natural Health Community Program and Well-Being: An Uncontrolled Study of Women Survivors of Domestic Violence
Get PDFThe purpose of this study was to evaluate a local natural healing service program and to explore how engagement in natural healing services related to the well-being of survivors of domestic violence. Using longitudinal secondary data, we conducted t-tests, regression, and correlation analysis on three measures (hope, distress, and empowerment) that were completed by the participants (N = 31). We provided evidence of the positive impact of a community-based natural healing services program on the well-being of survivors of domestic violence, specifically their sense of hope. This research represents the potential for natural healing services provided at the community level
