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Late‐life emergence of neuropsychiatric symptoms and risk of cognitive impairment in cognitively unimpaired individuals
Get PDFINTRODUCTION: Neuropsychiatric symptoms (NPS) often precede cognitive impairment. We investigated the longitudinal relationship between emergent, significant NPS and cognitive decline in cognitively unimpaired older adults. We also assessed the combined effect of NPS and Alzheimer's disease (AD) biomarkers on subsequent cognitive impairment.
METHODS: We included 190 cognitively unimpaired participants without NPS at baseline and tracked the emergence of significant NPS and conversion to mild cognitive impairment (MCI).
RESULTS: The average follow-up was 8.1 years, with a maximum of 19 years. Participants with emergent, significant NPS had a 3.92-fold higher risk of cognitive impairment than those without (95% confidence interval 1.51-10.17, P = 0.005). Individuals with NPS and AD biomarkers showed a markedly higher conversion rate to MCI than those with neither risk factor.
DISCUSSION: Our findings emphasize the role of emergent, significant NPS as early clinical indicators of cognitive impairment and suggest the potential benefit of incorporating clinical symptoms and neurobiological markers to better predict cognitive course.
HIGHLIGHTS: We investigated the association between emergent neuropsychiatric symptoms (NPS) and conversion to mild cognitive impairment (MCI). One hundred ninety cognitively unimpaired individuals were followed for an average of 8.1 years. Emergent NPS increased the risk of conversion to MCI > 3-fold. After emergent NPS, cognitive test performance declined. The co-occurrence of NPS and high cerebrospinal fluid phosphorylated tau181 amplified the risk of MCI
Idiomatic Correctness-Checking via Julienne in Fortran 2023
No full textThis paper presents a unified approach to unit testing and runtime assertion checking using Fortran 2023. The paper describes the support for our approach in the Julienne framework. Julienne leverages recent Fortran standards to implement object-oriented design patterns, support testing parallel programs, and implement functional programming patterns in order to craft idioms inspired by natural-language expressions. The presented idioms employ novel operators to write expressions that evaluate to a test-diagnosis object encapsulating two components: (1) the test outcome or assertion outcome and (2) an automatically generated diagnostic string. Two other novel aspects of the approach include (1) the ability to enforce assertions inside pure procedures and (2) the ability to output rich diagnostic information inside pure procedures during error termination when assertions fail. The latter capability mitigates against a reason that Fortran programmers commonly cite for not writing pure procedures: difficulty obtaining useful program output inside pure procedures when debugging code. This paper demonstrates how the adoption of the proposed idioms leads naturally to a unifying theme across two otherwise disparate technologies: unit testing and runtime assertion checking. Finally, this paper describes the usage of the Julienne testing framework for writing unit tests and assertions in the Matcha high-performance computing application and the Fiats deep learning library
Estimating the Momentary Likelihood of Posttraumatic Stress Symptoms During and After Exposure to Potentially Traumatic Events
Get PDFVerbal theories of posttraumatic stress (PTS) symptom development and maintenance—i.e., theories operationalized verbally rather than numerically, such as emotional processing theory and cognitive theory—suggest that PTS symptoms occur in specific sequences within individuals over time and interact to perpetuate and intensify each other. While prior research has leveraged ecological momentary assessment (EMA) data to investigate how PTS symptoms behave within individuals over time, such work has not served as a quantitative evaluation of verbal theories of PTS, due in part to the use of continuous or Likert survey item response types and reliance on the general linear model. These methodological choices result in findings that elucidate how PTS symptoms behave in general over a given period (e.g., an EMA sampling period) but do not shed light on symptom sequences, such as those described in verbal theories. Accordingly, the present study offers a first step towards the quantitative assessment of symptom sequences via a novel probabilistic approach. Within this probabilistic approach, PTS symptom clusters from the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition are first identified as present or absent at each point in time for each person. Next, the marginal probability (i.e., base rate) of each symptom cluster is calculated, which provides information about each point in time: Each symptom cluster base rate indicates the likelihood of the given symptom cluster occurring at each point in time for each person. With information about each point in time rather than about the full sampling period, the sequential relationships described in verbal theories of PTS may then be tested.The present study focuses on the initial step in this probabilistic approach: investigating the base rates of PTS symptom clusters. In so doing, this study offers a map or momentary epidemiology of the frequency with which PTS symptom clusters occur over time in adults with PTS. Six archival data sets of EMA PTS symptom data collected from 612 adults were identified for the present analyses. These six studies varied in four key factors hypothesized to influence the course of PTS: baseline PTS symptom severity, the proximity of EMA data collection to potentially traumatic event (PTE) exposure, EMA sampling rate, and survey item response type. The present study examined patterns of PTS symptom cluster base rates across an analytic subsample of 513 adults, and between subsamples split along these four key factors. All data were either collected via dichotomous item response type or discretized prior to analysis to evaluate frequency separately from severity or distress ratings (see Method).Findings showed that adults with PTS were highly likely to experience one or more PTS symptoms at any given point in time and on any given day, and that hyperarousal symptoms occurred at the highest frequency, followed by negative alterations in cognition and mood (NACM), re-experiencing, and avoidance, in that order. These findings affirm existing theoretical and clinical conceptualizations of PTS symptoms as occurring frequently within each day, with variation in behavior between symptom clusters. These findings were consistent regardless of baseline PTS symptom severity, proximity to PTE, EMA sampling rate, and survey item response type, indicating that these frequency characteristics may be core signatures of PTS.When comparing symptom cluster base rates across baseline PTS symptom severity, proximity to PTE, EMA sampling rate, and survey item response type, three additional central findings emerged. First, symptom cluster base rates were consistent across levels of baseline PTS symptom severity. For example, the frequency of hyperarousal symptoms in individuals with low baseline PTS symptom severity was not significantly different from the frequency of hyperarousal symptoms in individuals with high baseline PTS symptom severity. As baseline PTS symptom severity scores were generated via popular assessment tools—tools that combine symptom frequency and distress into a single severity metric—this finding suggests that distress, not symptom frequency, may have driven baseline PTS symptom severity scores. Measuring symptom frequency and distress separately in future work may lead to a more nuanced understanding of PTS and to increased precision in diagnostic practices. Second, symptom cluster base rates varied as a function of PTE proximity. This finding aligns with research showing the experience of PTS is different when enduring ongoing PTE exposure, within 30 days of PTE exposure, and 31+ days after PTE exposure. This affirms the importance of considering PTE proximity when studying and intervening on PTS. Finally, symptom cluster base rates varied according to both EMA sampling rate and survey item response type. For example, symptom cluster base rates in data collected via continuous items were significantly lower than base rates in data collected via Likert or dichotomous items. Careful follow-up investigations are needed to understand the impact of these methodological choices on existing and future psychological science outcomes.Overall, the present study shows general feasibility for extracting meaningful information from PTS symptom cluster base rates, provides evidence for the rank order of symptom cluster base rates as a relatively stable feature of PTS, demonstrates the utility of isolating symptom frequency from distress ratings, and offers additional nuance to existing work on the impact of PTE proximity, EMA sampling rate, and survey item response type on PTS symptom behavior findings. Future research should build on this work using a probabilistic approach to identify the likelihood of each symptom cluster given the presence of all other symptom clusters at the same time point and the next, and compare findings to symptom sequences outlined in verbal theories of PTS
Application of an obstetric comorbidity index to predict childhood cancer risk: a population based case-control study in Denmark
No full textBackgroundMaternal health during pregnancy appears to impact childhood cancer risk, yet comprehensive studies remain scarce. This study investigates associations between childhood cancer and multiple maternal comorbidities.MethodsA population-based case-control study was conducted using Danish national registers, with maternal health conditions identified from the National Patient Register and Medical Births Registry. We employed the Obstetric Comorbidity Index using ICD-8 and ICD-10 codes. The study population (1977–2013) included 6419 cases and 160484 matched controls. Conditional logistic regression estimated pediatric cancer risk.ResultsA maternal comorbidity score of one or more was linked to acute lymphocytic leukemia (ALL; OR = 1.07, 95%CI: 1.03–1.12), retinoblastoma (OR = 1.08, 95%CI: 0.94–1.23), and rhabdomyosarcoma (OR = 1.11, 95%CI: 0.98–1.26). Pre-existing diabetes (OR = 1.82, 95%CI: 1.28–2.59), previous cesarean delivery (OR = 1.20, 95%CI: 1.02–1.41), and gestational hypertension (OR = 1.27, 95%CI: 1.01–1.59) were associated with increased cancer risks in offspring. Slightly higher risks were noted for non-Hodgkin lymphoma (OR = 1.05, 95%CI: 0.96–1.16) and Burkitt lymphoma (OR = 1.08, 95%CI: 0.92–1.27) among children whose mothers had one or more comorbidities.ConclusionAn obstetric comorbidity index can predict childhood cancer risk. This highlights the need for targeted interventions to reduce adverse health consequences for offspring
Parental Attitudes and Predictors of Support for Youth-Directed Social Media Legislation in the United States
Get PDFAcross the United States, there has been an increase in policy initiatives aimed at regulating child and adolescent social media use. While an extensive body of work currently outlines the potential negative outcomes of early social media use, researchers have yet to examine the legislation itself, and more specifically, parents’ attitudes toward this legislation. We collected survey data from parents of 8-17-year-olds (N = 1359) across the United States between August and September 2023. Utilizing an exploratory, cross-sectional study design, we aimed to describe overall awareness of the legislation, as well as predict support for nine major provisions which cut across over 20 states’ bills. Results from hierarchical linear regressions show that parents are somewhat to strongly supportive of most of the legislation, with moral foundation salience (defined as the importance an individual places on five primary foundations of morality including care, fairness, loyalty, authority, and purity) being the most consistent predictor of support. Importantly, parents’ political ideology was not found to be significantly related to support for many of the included provisions. These findings hold important both theoretical and practical implications. First, in identifying moral foundation salience as a consistent predictor of legislative support, we extend our understanding of Moral Foundations Theory (MFT) and the extent to which moral sensibilities influence individuals’ attitudes and opinions. Further, identifying the lack of significance of political ideology offers an informative signal to policymakers of the bipartisan nature of support for social media legislation aimed at protecting minors
The Effects of Recent Federal Immigration Enforcement on California’s Private Sector Employment
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High Temperature Processing of Refractory Materials: Accelerated Methods for Densification and Integration
No full textAdvanced energy technologies, space/aerospace systems, and manufacturing tooling increasingly require operation under extreme temperatures, chemical attack, abrasion, and radiation. Refractory materials are prime candidates to meet these challenges, but their desirable properties make them difficult to process. Thus, there is a concerted effort to discover new refractory materials while simultaneously developing related efficient processing strategies.This dissertation investigates the science, synthesis, and processing of refractory materials using accelerated processing. The first half explores fundamental aspects of refractory compositionally complex alloys (RCCAs) and ceramics (CCCs), while the second examines fast/ultrafast processing of simple and complex refractory systems.Ni-activated sintering of MoNbTaW is presented as the first example of pressureless subsolidus activated sintering of a RCCA. A GB-λ diagram is computed for MoNbTaW-Ni to forecast high-temperature GB disordering and explain sintering trends. Weak Ni segregation in furnace-cooled specimens suggests GB “drying,” consistent with nanoscale GB precipitates. A new class of CCCs - M5Si3 silicides, are synthesized and densified via reactive spark plasma sintering of ball-milled powders. Remarkably, (V1/5Cr1/5Nb1/5Ta1/5W1/5)5Si3 forms a hexagonal γ phase, despite all constituent binary silicides being tetragonal (α or β). Cation ordering is also indicated—representing previously unreported phenomena in CCC’s.Reactive synthesis and ultrafast sintering of RCCA–CCC composites to high (~ 92–95 %) relative densities is demonstrated in ~70 s. Stearic acid supplied carbon is used to form a controlled fraction of hard subcarbide CCC phases, refining grain size and increasing hardness – demonstrating new strategies for microstructural engineering. The ultrafast sintering toolbox is expanded through new induction ultrafast sintering (IUS) schemes, achieving heating rates of 75–450 °C/s and showing rapid densification of Molybdenum (> 90 % density, 120 s) and 3-YSZ (> 96 % , 30 s), with further extension to complex refractory systems.Finally, Current Activated Reactive Ultrafast Joining (CARUJ) is proposed as a novel method enabling rapid SiC–SiC joining using flexible joule-heating elements for localized heating. Dense joints with tunable morphologies form in one step under minimal pressure, without post-infiltration, achieving average apparent shear strengths of ~15 MPa. The approach offers a versatile joining route potentially extendable to on-site component integration
Multiphysics Modeling of the kinetic physics of plasma interactions with neutrals
No full textThis dissertation investigates two distinct topics in kinetic plasma physics: (i) ionization waves, launched by laser-irradiated clustering gas jets, propagate into an ambient neutral gas, and (ii) high-Z impurity assimilation during cryogenic pellet injection for disruption mitigation in tokamaks.
In the first part, fully kinetic simulations are employed to study ionization waves generated by the expansion of laser-produced hot plasma into neutral gas. The expansion produces a GV/m-scale sheath field that ionizes neutrals into generated electrons and ions, and accelerates the generated electrons into the plasma, establishing a trapping field that confines hot electrons near the expanding front. When a MG-scale magnetic field is applied, penetration of the ionization front triggers electromagnetic wave emission, acting as a stopping mechanism. A kinetic model is developed to describe the steady-state front, identifying the key parameters governing ionization wave formation and stability.
The second part examines the assimilation of high-Z impurities from cryogenic pellets injected into fusion-grade plasmas. A self-similar solution describes the inward-moving recession front and outward-moving expansion front, revealing that ambipolar transport dominates the assimilation process. The front velocities scale with the local impurity ion sound speed. At the impurity expansion front, the electron temperature is determined by upstream hot-plasma conditions through a collisionless mechanism. To incorporate atomic physics, a simulation framework is developed that couples the fully kinetic VPIC code with a quasi-static collisional–radiative model (QSCRM), enabling self-consistent treatment of kinetic transport, ionization/recombination, and radiative cooling. This framework provides a first-principles capability for predictive modeling of high-Z impurity assimilation in fusion-grade plasmas, including the impact of radiation losses.
The results advance the understanding of plasma–neutral interactions in HED plasma experiments and plasma–impurity dynamics in high-Z pellet injection. The insights are applicable to optimizing experimental designs for laser-driven plasmas in neutral environments and improving predictive models for high-Z impurity transport in disruption mitigation. The developed simulation tool can be applied to numerical studies where both kinetic effects and radiative cooling of high-Z impurities play critical roles
The World of Care: Managing Disability in Qing China (1644-1911)
No full textHow did the Qing state, local communities, and families manage disability? What were people’s daily experiences, especially those of family members at the forefront of care? My dissertation, “ The World of Care: Managing Disability in Qing China(1644-1911),” answers these questions by arguing that disability was managed through care rather than cure: families bore primary responsibility, while the state and local communities supplemented and regulated care through law, charity, and moral governance. Drawing on Confucian classics, legal codes and casebooks, magistrates’ handbooks, local gazetteers, medical texts, vernacular fictions, and visual materials such as the Dianshizhai Pictorial, the study examines how disability was represented, administered, and lived.The project first argues that disability care sat at the center of Qing political life: the handling of disability formed a significant part of Qing discourse on imperial governance. Managing disability was not merely a technical project of alleviating individual need but a contested arena for the empire and its subjects. The Qing state primarily provided disability care through two institutions: law and charity. This care was selective. Not all disabled people qualified, and strict eligibility rules governed access. Second, the family remained the main provider of care. The kind and intensity of support—its form and its providers—depended on class, gender, age, and social and cultural norms. Arranged marriage often played an important role in enabling disabled individuals to marry and in embedding care within kinship. Shaped by Confucian ideals—female chastity, the growing valuation of male fidelity, filial piety, fraternal affection, and the extended family—people gave and received care in culturally specific ways. Lastly, I explore interactions among state, community, family, and disabled individuals. Disabled people were not passive recipients; they negotiated assistance, used legal and charitable institutions to their advantage, took on caregiving roles, contributed economically, and built self-governing communities. These examples challenge the image of disabled people as dependents, showing capacities for self-reliance and leadership within families and local communities. By tracing these interactions across state projects, community institutions, and family life, this dissertation reframes disability as an object of governance and recovers the living strategies of disabled people. By showing how “care” structured relations among empire, communities, families, and disabled individuals in Qing China, my work addresses a critical gap in global disability studies. It brings the Chinese context into view, offering cross-cultural perspectives that enrich both the study of premodern Chinese disability history and the broader field of disability studies