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Observation of the Yamaji effect in a cuprate and FL* theory of the pseudogap
No full textPhysicsAuthor's Origina
Implant Stability: A Prospective Clinical Study with a 2-year Follow-up
No full textAbstract
Purpose:
This prospective cohort study investigated the relationship between interproximal contact loss (ICL) and tactile sensitivity around implant-supported single-tooth restorations over an 18-month period.
Materials and Methods:
Twenty partially edentulous participants received posterior single-tooth implants restored with screw-retained monolithic zirconia crowns on custom titanium abutments. Interproximal contact tightness was quantitatively measured using a digital force gauge, and occlusal tactile sensitivity (osseoperception) was evaluated using progressively thicker occlusal foils. Contralateral natural teeth served as controls. Clinical assessments, including peri-implant plaque index, probing depths, and bleeding on probing, were performed at baseline and follow-up visits at 1, 3, 6, 12, and 18 months.
Results:
Only two of 20 implant sites (10%) developed open interproximal contacts, both within six months of crown delivery. Most contacts remained functionally closed, with only modest decreases in contact force over time. Tactile sensitivity thresholds were consistently higher for implant sites compared to control teeth, though differences were not statistically significant (p > 0.05). Peri-implant soft tissue health remained stable across all time points.
Conclusions:
The incidence of interproximal contact loss in this cohort was low, with no adverse effects on peri-implant health. Although implant restorations demonstrated higher tactile thresholds than natural teeth, perceptual function improved over time. These findings highlight the need for continued monitoring of contact stability, particularly in the mandible, and support the potential for limited osseoperception in implant-supported crowns.Prosthodontic
Threat Learning Processes as Mechanisms Linking Childhood Trauma and Psychopathology: Translating Between Environmental Experience, Neurobiology, and Behavior
No full textExposure to childhood trauma is one of our most robust known risk indicators for the development of psychopathology, yet the mechanisms linking childhood trauma with transdiagnostic psychopathology remain incompletely understood. Childhood trauma, defined as exposure to serious forms of interpersonal violence like physical abuse, sexual abuse, and domestic violence, is characterized by an unexpected introduction of danger or threat into the environment. These experiences may fundamentally alter the way individuals learn to detect, interpret, and respond to environmental threat in ways that contribute to trajectories towards psychopathology. Across a series of three studies, this dissertation investigates the ways in which neurobiological, psychophysiological, and behavioral bases of three threat learning processes may serve as mechanisms linking childhood trauma with transdiagnostic psychopathology in developmental populations.
In Study 1 (N = 147, ages 8-16), we examined the temporal dynamics of neural activation and patterns of functional connectivity during threat conditioning in youth with (n = 77) and without (n = 70) exposure to childhood trauma and evaluated whether these patterns mediated the association of childhood trauma and psychopathology in a longitudinal design. Youth with childhood trauma exposure exhibited neural patterns broadly consistent with difficulty discriminating between threat and safety cues and reduced coupling between regions involved in threat learning and contextual processing. These alterations mediated the link between childhood trauma and transdiagnostic psychopathology two years later, suggesting altered threat conditioning is one pathway from childhood trauma to mental health difficulties.
Study 2 (N = 100, ages 9-19) builds upon Study 1 by examining whether neural alterations in threat reversal learning served as a mechanism linking childhood trauma and psychopathology, targeting the ability to flexibly update conditioned threat and safety associations based on changing contextual significance. In this paradigm, where heightened unpredictability is highlighted due to the contingency reversal, youth with childhood trauma demonstrated heightened discrimination between cues in a key threat-learning region and reduced discrimination in safety-learning regions that mediated the link between childhood trauma and lower transdiagnostic anxiety symptoms within the trauma group only. This pattern of results suggests a potential environmental experience-dependent pathway to resilience.
Study 3 (N = 75, ages 13-18) extends a similar line of inquiry to the physiological and behavioral underpinnings of threat generalization in a developmental sample with a wide range of exposure to childhood trauma, measured dimensionally. Using a novel methodological approach to the operationalization of threat generalization employing advanced machine learning techniques and nonlinear modeling, we demonstrate the ability to identify distinctly shaped gradients of generalization across measurement modalities. While we did not find associations of threat generalization with childhood trauma and observed weak evidence for potential associations of threat generalization with psychopathology, this occurred in the context of important limitations related to the sample and power. This study serves as a preliminary proof-of-concept and suggests that the question of whether altered threat generalization mediates the link between childhood trauma and psychopathology merits further investigation.
Taken together, this series of studies highlights the myriad of ways that learning about threat may be altered following exposure to childhood trauma in ways that are relevant to mental health. Elucidating the underpinnings of these mechanisms aims to provide valuable insight towards the etiology of psychopathology, ultimately aiming to inform the optimization and innovation of clinical interventions.Psycholog
What Board-level Control Mechanisms Changed in Banks Following the 2008 Financial Crisis? A Descriptive Study
No full textFollowing the 2008 financial crisis, the Financial Crisis Inquiry Commission (FCIC) identified major shortcomings in bank board governance, contributing to systemic risk management failures. This study adapts a management control framework and empirically examines changes in board-level “process control” and “input control” mechanisms in 95 large U.S. bank holding companies (2000–2015) and contrasts these with 1,452 nonbanks. Our findings indicate that most post-2008 improvements occurred in "process controls," e.g. Chief Risk Officer (CRO) appointments increased from 53% pre-crisis to 91% post-crisis, with significantly more banks establishing a dedicated risk committee and identifying the committee responsible for reputation management. We also find progress in "input control” related to domain knowledge with an increase of 16% in new bank directors with prior risk management experience, and significant increase in directors with other relevant domain knowledge. We observed limited or no change in control mechanisms related to improving the board members’ ability to voice different perspectives or commit more time to their role. Our results show that improvements in certain types of controls seem to have taken precedence over others which have implications for explaining and implementing changes in corporate governance and control mechanisms.Author's Origina
The Geopolitics of Surveillance Capitalism
Get PDFSurveillance capitalism is a new form of capitalism that turns human behavior into data to be tracked, analyzed, and monetized. However, this narrow framing obscures the deeper architecture that allows surveillance capitalism to thrive. Surveillance capitalism is not just a business model. It is a geopolitical system with institutional scaffolding. It is grounded in regulation (or lack of), legitimized by economic theory, promoted by trade rules, and protected by powerful countries. Its sustainability depends on more than market incentives; it is built on a distributed architecture of norms, institutions, actors, and governance failures.
At its core, surveillance capitalism is an extractive political economy built on the systematic capture and monetization of human experience. As Shoshana Zuboff argues, this system represents an “epistemic coup,” in which corporations unilaterally assert ownership over behavioral data, undermining both privacy and democratic legitimacy. This is not only the privatization of information, it is also the expropriation of the very condition of self-knowledge and collective autonomy. This coup did not occur by accident. It was made possible by deliberate political choices, neoliberal market ideologies, legal loopholes, and the strategic retreat of the democratic state (Zuboff 2022a).
The surveillance capitalist order extends far beyond tech companies. It is built on a set of foundational assumptions about markets, innovation, and governance. It draws on economic theories that treat data as a neutral input and surveillance as the price of personalization. It is reinforced by legal doctrines, from trade secret protections to arbitration rules, that prioritize corporate control over democratic oversight. And it is institutionalized through international organizations, development finance institutions, and standard-setting bodies that diffuse and normalize extractive data practices as a form of modernity and progress. While the United States is often seen as the chief architect and promoter of surveillance capitalism, the system it anchors is far from national. Regional and bilateral trade agreements protect cross-border data flows while restricting the ability of other governments to regulate. Development institutions promote digital infrastructure projects that deepen surveillance logics in the Global South, often under the banner of inclusion. Multilateral forums and technical standards bodies entrench the norms of “trustworthy AI” and “data free flows with trust,” offering legitimacy without transparency. All these are geopolitical strategies embedded in regulation, code, and economics.
This paper takes a bird’s-eye view of the global surveillance eco-
system. It maps the institutional foundations and geopolitical dy-
namics that sustain it. It traces the actors, alliances, and narratives
that normalize mass corporate surveillance and promote the glob-
al surveillance capitalist economy. It goes beyond a Big Tech cri-
tique and traces how power is produced, distributed, and enforced
across this global order. Surveillance capitalism is a geopolitical
system, and dismantling it requires more than privacy reforms or
antitrust action. It requires structural transformation of the polit-
ical, legal, and epistemic arrangements that have enabled it. This
paper aims to lay the groundwork for coordinated action.Author's Origina
Managed Expectations Theory: Ex Ante Likelihoods Influence Ex Post Utilities
Get PDFDaniel Kahneman, often in collaboration with Amos Tversky, developed foundational frameworks for understanding human decision-making. Building on that tradition, this article proposes that individuals’ ex ante assessments of the likelihood of good and bad outcomes serve as reference points that shape the ex post utility of lottery outcomes. In prospect theory, prior holdings act as reference points for evaluating outcomes—but probabilities themselves play no such role. This article introduces Managed Expectations Theory, which rests on two core hypotheses: 1. Reference Point Hypothesis: Ex ante probabilities serve as reference points for ex post utility. Specifically, more pessimistic expectations about uncertain outcomes enhance ex post utility, regardless of whether the outcome turns out to be good or bad. Four experiments, using a nationally representative adult sample of over 1,000 participants, strongly support this hypothesis. Lower [higher] ex ante likelihoods are associated with greater ex post utility for good [bad] outcomes. 2. Created Likelihoods Hypothesis: Recognizing that likelihood assessments act as reference points, individuals deliberately manage these assessments to be more pessimistic than an objective or statistical “outside view”—in order to boost their ex post utilities. Supporting this conjecture, the good outcomes participants labeled as “likely” occurred far more often than the bad outcomes they labeled as “likely.” These created likelihoods help explain a central feature of prospect theory’s probability weighting function: the underestimation of high-probability good events and the overestimation of low-probability bad events.Version of Recor
Exploring the Role of Physical and Virtual Manipulatives in Elementary Mixed Fractions Learning
No full textUnderstanding how different types of manipulatives influence children’s learning of mixed fractions can provide insight into effective instructional strategies and inform educational interventions. While both physical and virtual manipulatives are widely used in mathematics education, research comparing their relative effectiveness—particularly in relation to sequencing and retention—is still limited (Moyer-Packenham & Westenskow, 2013; Westenskow, 2013).
The present study investigated whether sequencing physical and virtual manipulatives across two weeks influences children’s ability to identify, compare, and add mixed fractions. Twenty children were assigned to one of four groups: two groups used the same manipulative type across both weeks (physical or virtual), while the remaining two groups switched manipulative types between weeks. Pre- and post-tests were administered in Weeks 1 and 2 to assess performance across the three mixed fraction skills and to evaluate the effects of sequencing and retention.
Although results were not statistically significant, descriptive analyses indicated that all groups improved in all skill areas using manipulatives. Non-sequencing groups generally achieving greater learning gains, while groups using virtual manipulatives demonstrated higher retention from Week 1 to Week 2.
This study contributes to the growing literature on manipulative-based learning and highlights the need for further research on how sequencing and manipulative type affect children’s acquisition and retention of mathematical concepts.Extension Studie
Scientific distinctions between coca and cocaine support policy reform
No full textCoca is not cocaine—it is an ancient, safe, and culturally vital crop now under renewed scrutiny by the World Health Organization, whose review could prompt revision of United Nations drug policy rooted in colonialist bias and begin to repair decades of social injustice, while affirming scientific evidence and cultural sovereignty.Organismic and Evolutionary BiologyAccepted Manuscrip
An Insider’s Perspective on How to Reduce Fraud in the Social Sciences
No full textI will describe how a fraudulent paper developed and offer insights into the institutional changes that are needed. I was a co-author on a paper described as a “clusterfake” due to at least two frauds allegedly occurring in the same paper. I will use my knowledge of behavioral ethics and my experience as a co-author on a fraudulent paper to explore changes that are needed to improve research integrity.Accepted Manuscrip
Communicating Common Goal Knowledge Improves Trust-Calibration in Human-AI Collaboration
No full textIn Human-AI collaboration, human agents often have a clear goal in mind and the AI Assistant tries to help users achieve their goals more efficiently. However, inferring users’ goals is non-trivial based on noisy user behavior and there is often mismatch in agent’s belief about each other’s knowledge of the ground-truth goal, leading to coordination failure. In this study, we propose that building common goal knowledge through communication improves human user’s mental model of the AI Assistant and leads to more efficient and effective human-AI collaboration. To test this hypothesis, we design an experiment where an AI assistant helps a human user shop for recipes on a grocery platform. We compare the user behavior and team performance under three experimental conditions: AI providing no information over its knowledge over human goals, AI expressing its belief over human’s goal through verbal communication(“Show”) and AI indicating its confidence in its belief over human’s goal (“Tell”). We find that communicating goal knowledge (in “Show” and “Tell”) increases user’s tendency to use AI when AI is indeed correct and improves user’s subjective ratings of the AI assistant.Proo