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Measurement is the weak link between theory and empirical test. Complex concepts such as ideology, identity, and legitimacy are difficult to measure; yet, without measurement that matches theoretical constructs, careful empirical studies may not be testing that which they had intended. Item response theory (IRT) models offer promise by producing transparent and improvable measures of latent factors thought to underlie behavior. Unfortunately, those factors have no intrinsic substantive interpretations. Prior solutions to the substantive interpretation problem require exogenous information about the units, such as legislators or survey respondents, which make up the data; limit analysis to one latent factor; and/or are difficult to generalize. We propose and validate a solution, IRT-M, that produces multiple, potentially correlated, generalizable, latent dimensions, each with substantive meaning that the analyst specifies before analysis to match theoretical concepts. We offer an R package and step-by-step instructions in its use, via an application to survey data.
In this paper, we explore the applications of Tail Variance (TV) as a measure of tail riskiness and the confidence level of using Tail Conditional Expectation (TCE)-based risk capital. While TCE measures the expected loss of a risk that exceeds a certain threshold, TV measures the variability of risk along its tails. We first derive analytical formulas of TV and TCE for a large variety of probability distributions. These formulas are useful instruments for relevant research works on tail risk measures. We then propose a distribution-free approach utilizing TV to estimate the lower bounds of the confidence level of using TCE-based risk capital. In doing so, we introduce sharpened conditional probability inequalities, which halve the bounds of conventional Markov and Cantelli inequalities. Such an approach is easy to implement. We further investigate the characterization of tail risks by TV through an exploration of TV’s asymptotics. A distribution-free limit formula is derived for the asymptotics of TV. To further investigate the asymptotic properties, we consider two broad distribution families defined on tails, namely, the polynomial-tailed distributions and the exponential-tailed distributions. The two distribution families are found to exhibit an asymptotic equivalence between TV and the reciprocal square of the hazard rate. We also establish asymptotic relationships between TCE and VaR for the two families. Our asymptotic analysis contributes to the existing research by unifying the asymptotic expressions and the convergence rate of TV for Student-t distributions, exponential distributions, and normal distributions, which complements the discussion on the convergence rate of univariate cases in [28]. To show the usefulness of our results, we present two case studies based on real data from the industry. We first show how to use conditional inequalities to assess the confidence of using TCE-based risk capital for different types of insurance businesses. Then, for financial data, we provide alternative evidence for the relationship between the data frequency and the tail categorization by the asymptotics of TV.
In this manuscript, we address open questions raised by Dieker and Yakir (2014), who proposed a novel method of estimating (discrete) Pickands constants $\mathcal{H}^\delta_\alpha$ using a family of estimators $\xi^\delta_\alpha(T)$, $T>0$, where $\alpha\in(0,2]$ is the Hurst parameter, and $\delta\geq0$ is the step size of the regular discretization grid. We derive an upper bound for the discretization error $\mathcal{H}_\alpha^0 - \mathcal{H}_\alpha^\delta$, whose rate of convergence agrees with Conjecture 1 of Dieker and Yakir (2014) in the case $\alpha\in(0,1]$ and agrees up to logarithmic terms for $\alpha\in(1,2)$. Moreover, we show that all moments of $\xi_\alpha^\delta(T)$ are uniformly bounded and the bias of the estimator decays no slower than $\exp\{-\mathcal CT^{\alpha}\}$, as T becomes large.
Candida auris is an emerging fungal pathogen increasingly recognized as a cause of healthcare-associated infections including outbreaks.
Methods:
We performed a mixed-methods study to characterize the emergence of C. auris in the state of Maryland from 2019 to 2022, with a focus on socioeconomic vulnerability and infection prevention opportunities. We describe all case-patients of C. auris among Maryland residents from June 2019 to December 2021 detected by Maryland Department of Health. We compared neighborhood socioeconomic characteristics of skilled nursing facilities (SNFs) with and without C. auris transmission outbreaks using both the social vulnerability index (SVI) and the area deprivation index (ADI). The SVI and the ADI were obtained at the state level, with an SVI ≥ 75th percentile or an ADI ≥ 80th percentile considered severely disadvantaged. We summarized infection control assessments at SNFs with outbreaks using a qualitative analysis.
Results:
A total of 140 individuals tested positive for C. auris in the study period in Maryland; 46 (33%) had a positive clinical culture. Sixty (43%) were associated with a SNF, 37 (26%) were ventilated, and 87 (62%) had a documented wound. Separate facility-level neighborhood analysis showed SNFs with likely C. auris transmission were disproportionately located in neighborhoods in the top quartile of deprivation by the SVI, characterized by low socioeconomic status and high proportion of racial/ethnic minorities. Multiple infection control deficiencies were noted at these SNFs.
Conclusion:
Neighborhood socioeconomic vulnerability may contribute to the emergence and transmission of C. auris in a community.
Shock–droplet interaction in the early stage involves intricate wave structures. Investigating this phenomenon is inherently challenging due to the fine spatial and temporal scales involved. Past research has suggested that the occurrence of cavitation, marked by a negative peak pressure, is linked to the focus of the reflected expansion wave. In this study, a high-fidelity compressible numerical approach is utilized to replicate the initial phase of shock–droplet interactions. The location of the negative peak pressure is meticulously documented and compared with experimental measurement and numerical results. Results indicate a strong alignment between the negative peak pressure positions identified through numerical simulations and the focal points identified in theoretical models for low gas–liquid wave velocity ratios. However, this alignment is notably disrupted when dealing with higher gas–liquid wave velocity ratios. Further enhancements are made to the theoretical model, enabling a more precise depiction of internal wave structures and focus points, particularly under conditions of high gas–liquid wave velocity ratios. The study delves into the various factors influencing internal pressure fluctuations within the liquid droplet, categorizing them into four phases: the shock wave effect, relaxation effect, fluctuation effect, and expansion wave effect. Analysing the pressure decrease portion reveals that while the converging of the reflected expansion wave leads to a substantial pressure drop, it accounts for only a fraction of the total pressure variation. Consequently, any model predicting negative peak pressure positions must comprehensively consider all contributing factors.
The large volume of seemingly conflicting guidance on the management of borderline personality disorder (BPD), combined with the ongoing shortage of specialised resources, can make the task feel like an exclusive undertaking that the general psychiatrist is underprepared for. In this article, we distil current evidence to submit that sound psychiatric management principles used to treat all serious and enduring mental disorders (diagnostics, comorbidity management, rational pharmacotherapy and dynamic risk management) are readily applicable and particularly therapeutic for BPD. We offer actionable practice guidance that we hope will render the clinical management experience a more lucid and rewarding one for both practitioner and patient.
Anxiety disorders are a major public health burden with limited treatment options.
Aims
We investigated the long-term safety and efficacy of lysergic acid diethylamide (LSD)-assisted therapy in patients with anxiety with or without life-threatening illness.
Method
This study was an a priori-planned long-term follow-up of an investigator-initiated, two-centre trial that used a double-blind, placebo-controlled, two-period, random-order, crossover design with two sessions with either oral LSD (200 μg) or placebo per period. Participants (n = 39) were followed up 1 year after the end-of-study visit to assess symptoms of anxiety, depression and long-term effects of psychedelics using Spielberger's State-Trait Anxiety Inventory–Global (STAI-G), the Beck Depression Inventory (BDI), the Persisting Effects Questionnaire and measures of personality traits using the NEO-Five-Factor Inventory.
Results
Participants reported a sustained reduction of STAI-G scores compared with baseline (least square means (95% CI) = −21.6 (−32.7, −10.4), d = 1.04, P < 0.001, for those who received LSD in the first period (94 weeks after the last LSD treatment) and −16.5 (−26.2, −6.8), d = 1.02, P < 0.05, for those who received LSD in the second period (68 weeks after the last LSD treatment)). Similar effects were observed for comorbid depression with change from baseline BDI scores of −8.1 (−13.2, −3.1), d = 0.71, P < 0.01, and −8.9 (−12.9, −4.9), d = 1.21, P < 0.01, for the LSD-first and placebo-first groups, respectively. Personality trait neuroticism decreased (P < 0.0001) and trait extraversion increased (P < 0.01) compared with study inclusion. Individuals attributed positive long-term effects to the psychedelic experience.
Conclusions
Patients reported sustained long-term effects of LSD-assisted therapy for anxiety.
This study investigates the nexus between the rise of female leaders and the appointment of women to cabinets and how family ties, crucial for women’s political ascendance, impact these appointments. Using a unique dataset across 160 countries from 1966 to 2021, we find that female leaders generally appoint more women to their cabinets and key cabinet roles. However, this effect is significantly moderated by the “Goldilocks” principle, defined by the nature of a leader’s family ties. Specifically, female leaders with moderate family ties are most likely to appoint women. In contrast, their counterparts from political dynasties and those without familial political ties are less inclined to do so. The exploratory analysis suggests potential mechanisms driving this dynamic: female leaders with a “just-right” degree of political lineage are more likely to have advanced degrees and Western education, potentially aligning them more closely with liberal and feminist values.
Diabetes and depression have a bidirectional relationship, but some antidepressants (such as the tricyclics) may have detrimental effects in diabetes that are exacerbated by behavioural changes associated with depression. This month's Cochrane Review evaluated the efficacy of psychological and pharmacological treatments of comorbid depression in diabetes and found that such interventions have a moderate and clinically significant effect on depression outcomes in people with diabetes. However, conclusions were limited by significant heterogeneity within examined populations and interventions, and significant risk of bias within trials. This commentary critically appraises the review and aims to contextualise its findings.
Persistent gender inequalities in internal political efficacy have traditionally been attributed to gender differences in resources. This article complements the resource model by focusing on how gendered political socialization occurs during citizenship education and how citizenship education might mitigate, reproduce, or intensify inequalities. Based on multilevel models on a 2016 survey dataset (3898 students across 150 schools) of Belgian senior high school students, we show that citizenship education increases internal political efficacy for both male and female students. However, we also find that citizenship education intensifies inequalities since male students gain more from it than female students, especially in schools with a conservative gender role culture. Our results indicate that the influence of citizenship education depends on the gendered school context in which it is offered. In this respect, citizenship education risks intensifying rather than mitigating gender inequalities.
We investigated how environmental conditions translate into reproductive success or failure in Aurelia aurita from the medusa to the polyp life stage. This study examined how: (i) settlement success and development of planula larvae and polyps vary across the year, (ii) the role of temperature in determining the successful settlement of larvae and growth of polyps, and (iii) the influence of maternal provisioning in the successful settlement of larvae and growth of polyps. Medusae were collected monthly from February to December 2019 from Horsea Lake, UK. Planula larvae were settled in conditions mimicking the in situ temperature and salinity of collection. For the individual treatments, planula collected in August settled most rapidly. Early development rates (<8 tentacles) were significantly higher than later growth rates (>8 tentacles) and were positively correlated with temperature, unlike later growth rates. Planula length, used as an indicator of maternal provisioning, varied significantly across the year. In July 2019, a high temperature anomaly coincided with an increased time spent by planula larvae in the water column. Increasing temperatures past thermal limits through the increasing occurrence of temperature anomalies is likely to be detrimental to larval settlement and indirectly to the replenishment of temperate polyp populations.
Researchers are increasingly reliant on online, opt-in surveys. But prior benchmarking exercises employ national samples, making it unclear whether such surveys can effectively represent Black respondents and other minorities nationwide. This paper presents the results of uncompensated online and in-person surveys administered chiefly in one racially diverse American city—Philadelphia—during its 2023 mayoral primary. The participation rate for online surveys promoted via Facebook and Instagram was .4%, with White residents and those with college degrees more likely to respond. Such biases help explain why neither our surveys nor public polls correctly identified the Democratic primary’s winner, an establishment-backed Black Democrat. Even weighted, geographically stratified online surveys typically underestimate the winner’s support, although an in-person exit poll does not. We identify some similar patterns in Chicago. These results indicate important gaps in the populations represented in contemporary opt-in surveys and suggest that alternative survey modes help reduce them.
Egg masses from an unknown mollusc have been found in South-West Iceland since 2020, but it was not until September 2023 that the adult organism was collected. Morphological analysis of both adults and egg masses pointed towards the identification of the species as Melanochlamys diomedea. This was further confirmed through DNA analyses using COI, H3, and 16S rRNA markers, which established the presence of a new non-indigenous species in the North Atlantic. Members of the genus Melanochlamys have predominantly been found in the Indo-Pacific basin and the Pacific Ocean, with only one species known to exist across the Madeira Islands, Canary Islands, and Cape Verde in the Atlantic. The known distribution range of M. diomedea extends from Alaska to California on the Pacific side of North America, where it typically inhabits sandy-muddy areas of the littoral in the tidal zone and below. It is not known how the species arrived in Iceland. However, maritime transport through either ballast water or biofouling is being considered as the most likely mode of dispersal.
There is a lack of data on mental health service utilisation and outcomes for people with experience of forced migration living in the UK. Details about migration experiences documented in free-text fields in electronic health records might be harnessed using novel data science methods; however, there are potential limitations and ethical concerns.
Polynesia is a hotspot for marine biodiversity in the South Pacific Ocean, yet the distribution of many invertebrate taxa in this region is still often poorly assessed. Information on the diversity and phylogeography of sponges in particular remains limited in spite of their importance for coral reef ecosystems. Recent expeditions to the island group of Wallis and Futuna enabled the first larger-scale assessment of the Wallis Island sponge fauna, resulting in the molecular identification of 82 unique Molecular Operational Taxonomic Units (MOTUs) from 339 sponge samples based on 28S C-region rDNA and CO1 mtDNA data. Faunal comparisons with both adjacent archipelagos and more distant Indo-Pacific regions were predominantly based on the MOTUs obtained from Wallis Island ecoregions, and suggest high levels of endemism of sponges in Wallis and Futuna, corroborating previous data on the biodiversity of sponges and other marine phyla in the South Pacific. The results of this molecular taxonomic survey of the Wallis and Futuna sponge fauna aim to lay solid foundations for a sustainable ‘Blue Economy’ in Wallis and Futuna for the conservation of their local coral reefs.
The influence of free-stream conicity on the various aspects of the flow over a spherical test model is examined using both analytical and numerical methods. For the analytical method, a simple closed-form analytical model is assembled. Six different free-stream conditions with different Mach numbers, Reynolds numbers and thermochemistry are tested at four different degrees of conicity corresponding to those which can realistically be encountered in experiments. It is found that the results around the stagnation point are mostly insensitive to the flow condition and gas type, except for some mild non-equilibrium effects, and excellent agreement between the analytical and numerical results exists. The shock stand-off distance on the stagnation streamline is shown to decrease with increasing conicity. This decrease increases the tangential velocity gradient at the stagnation point, increasing the stagnation point heat flux and decreasing the stagnation point boundary layer thickness. The free-stream conicity is also found to alter the normalized distributions of the shock stand-off distance, heat flux, surface pressure and boundary layer thickness with the angle from the stagnation point. In general, increasing the conicity magnifies the slope of these distributions. Regarding the boundary layer transition, it is found that, if it occurs in a uniform free stream, it would also occur in a conical free stream, albeit with the transition point shifted upstream closer to the stagnation point due to the increase in the boundary layer edge tangential velocity. Overall, considering the relevant experimental uncertainties, corrections for free-stream conicity are generally recommended when larger test models are used.
Particle segregation in dense flowing size-disperse granular mixtures is driven by gravity and shear, but predicting the associated segregation force due to both effects has remained an unresolved challenge. Here, a model of the combined gravity- and kinematics-induced segregation force on a single intruder particle is integrated with a model of the concentration dependence of the gravity-induced segregation force. The result is a general model of the net particle segregation force in flowing size-bidisperse granular mixtures. Using discrete element method simulations for comparison, the model correctly predicts the segregation force for a variety of mixture concentrations and flow conditions in both idealized and natural shear flows.
To date, a growing body of literature has documented the existence and impacts of coherent structures known as large- and very-large-scale motions within wall-bounded turbulent flows under neutral and unstable thermal stratification. These coherent structures can account for a considerable fraction of the overall turbulent transport and have been found to modulate small-scale turbulent fluctuations near the wall. In the context of stably stratified flows, however, the examination of such coherent structures has garnered relatively little attention. Stable stratification limits vertical transport and turbulent mixing within flows, which makes it unclear the extent to which previous findings on coherent structures under unstable and neutral stratification are applicable to stably stratified flows. In this study, we investigate the existence and characteristics of coherent structures under stable stratification with a wide range of statistical and spectral analyses. Outer peaks in premultiplied spectrograms under weak stability indicate the presence of large-scale motions, but these peaks become weaker and eventually vanish with increasing stability. Quadrant analysis of turbulent transport efficiencies (the ratio of net fluxes to their respective downgradient components) demonstrates dependencies on both stability and height above ground, which is evidence of morphological differences in the coherent structures under increasing stability. Amplitude modulation by large-scale streamwise velocity was found to decrease with increasing gradient Richardson number, whereas modulation by large-scale vertical velocity was approximately zero across all stability ranges. For sufficiently stable stratification, large eddies are suppressed enough to limit any inner–outer scale interactions.