Ursinus College

Latine Americans, the largest racial minority group in the United States, exhibit significant intragroup diversity in physical appearance. Research shows that Latine people are perceived as racially ambiguous, with few facial features used to reliably identify them. Our research examines the role of skin tone in the implicit categorization and stereotyping of Latine Americans. Across three studies (N = 782), we found that Latine individuals with medium skin tones were more likely to be implicitly associated with the Latine category (Studies 1a and 1b) and perceived as foreigners compared to those with lighter skin tones (Study 2). Although all participants associated darker skin with being Latine and foreign, Latine participants did so to a lesser extent than non-Latine participants. These findings suggest that skin tone plays a key role in how both Latine and non-Latine individuals implicitly categorize someone as Latine, with prototypical targets more likely to be associated with negative stereotypes.

Energy expenditure strongly influences an animal’s foraging decisions and activity budgets. Diving animals especially need to be energetically efficient because they exercise while oxygen is limited. By estimating the energetics of behavior, we can better understand the cascading effects of individual responses to disturbance and environmental change. Pacific Coast Feeding Group (PCFG) gray whales use a variety of foraging tactics in shallow habitats (<20 m), which present challenges associated with maneuverability and buoyancy. We use a seven-year dataset of concurrent individual behavior, morphology, and breath-by-breath respiration data collected via drone paired with two years of tri-axial accelerometry tag data to study patterns and correlates of respiration. We assess how several respiration metrics (acting as proxies for oxygen consumption) are associated with individual length, body condition and behavior (forage and travel), and test whether respiration reflects recovery from, or anticipation of, a foraging dive using Bayesian linear mixed effects models. Given model results, we simulated daily field metabolic rate (FMR) to explore how diving costs may affect energetics at a daily scale. We find that respiration reflects recovery from the preceding dive and that dives are more energetically expensive for longer, more buoyant whales. Longer dives and the most common foraging tactics also incur higher energetic costs. FMR simulations show that individual size and dive duration have the largest effects on energy expenditure. Thus, PCFG gray whale foraging success may be limited by the energetic costs associated with size and buoyancy, highlighting the costs of a shallow habitat foraging niche.

The purpose of this study was to assess the effect of a KN95 mask on the performance, physiological response, and perception of high-intensity interval training (HIIT). Twenty college-aged participants (Male: 10, Female: 10) completed a two-visit, crossover, counterbalanced study. The HIIT workout included four 1-minute “all-out” intervals at 3.5% of body mass with 4-minute rest intervals, performed with or without a KN95 mask. Following HIIT, participants remained on the cycle ergometer for a 15-minute recovery period. For each interval, peak power and average power were recorded. Throughout the HIIT workout and recovery, heart rate, blood lactate, muscle oxygenation, perceived exertion, and perceived recovery were measured. All data were assessed using trial×time ANOVAs with post hoc pairwise comparisons. Alpha level was set to p<0.05. All data are presented as mean±standard deviation. No significant interactions were noted for peak power (p=0.432), average power (p=0.674), blood lactate (p=0.533), perceived exertion (p=0.221), perceived recovery (p=0.333), or muscle oxygenation (p=0.991). A significant main effect of trial was noted for heart rate during recovery, with higher heart rate during the masked trial compared to control. A KN95 mask did not affect performance, physiological response, or perception during HIIT, though it led to elevated heart rate during recovery. These results suggest KN95 masks may not impair HIIT performance but can influence short-term post-exercise heart rate recovery.

Stereotypical motor movements (SMM) are a core diagnostic feature of autism that remain difficult to quantify efficiently and validly across individuals and developmental stages. The current paper presents a novel pipeline that leverages Topological Data Analysis to quantify and characterize recurrent movement patterns. Specifically, we use persistent homology to construct low-dimensional, interpretable feature vectors that capture geometric properties associated with autistic SMM by extracting periodic structure from time series derived from pose estimation landmarks in video data and accelerometer signals from wearable sensors. We demonstrate that these features, combined with simple classifiers, enable accurate automated quantification of autistic SMM. Visualization of the learned feature space reveals that extracted features generalize across individuals and are not dominated by person-specific SMM. Our results highlight the potential of using mathematically principled features to support more scalable, interpretable, and person-agnostic characterization of autistic SMM in naturalistic settings.

We have measured the $0_{g.s.}^+ \rightarrow 2_1^+$ transition in the neutron rich $N=28$ isotope $^{42}$Si using the probes of intermediate energy Coulomb excitation and inelastic proton scattering in inverse kinematics at the Facility for Rare Isotope Beams with beam particle rates of $\approx 5$ particles/s. The results of these two measurements allowed us to determine $M_n/M_p$, the ratio of the neutron and proton transition matrix elements for the $0_{g.s.}^+ \rightarrow 2_1^+$ transition. In addition, we have measured the $0_{\mathrm{g.s.}}^+ \rightarrow 2_1^+$ transition in the isotone $^{44}$S using inverse kinematics inelastic proton scattering. By comparing the $^{44}$S proton scattering result with a recent intermediate energy Coulomb excitation result on the same transition, we were able to determine $M_n/M_p$ for the $0_{g.s.}^+ \rightarrow 2_1^+$ transition in this nucleus as well. This work strengthens the evidence that $^{42}$Si has a stable quadrupole deformation in its ground state and that $^{44}$S does not. Both conclusions are further supported by shell model calculations carried out with the FSU interaction.

IntroductionThe ESA ExoMars Rosalind Franklin (EMRF) rover will launch in 2028, and land in the Oxia Planum region of Mars. The main target is Noachian phyllosilicate-rich deposits [1,2]. This region probably represents the oldest aqueous environments to be explored in situ on Mars. In this study we have investigated extensive secondary craters within the EMRF landing ellipse, to place absolute age markers in the stratigraphic framework of Oxia Planum, and identify the likely primary source crater(s). We pay particular attention to possible secondary craters from Mojave crater, due to its likely recent formation age [3] and importance as a potential source crater for martian meteorites [4]. MethodWe first used the recent Mars catalogue of small impact craters [5, 6] in a small (1 x 105 km2) ‘Oxia Planum study region’. We refined the crater identification through manual crater addition, deletion, movement, and scaling. We produced a final catalogue with an extra 22,209 craters, totalling 381,584 impact craters. We applied the ‘Algorithm for the Secondary Crater Identification’(ASCI) [3] to identify possible primary and secondary impact craters. We then produced a crater size density map of possible secondary craters for the Oxia Planum study region, from which we identified acute triangle-shaped clusters (or ‘cones’) of craters. We carried out crater size-frequency distribution (CSFD) studies of previously-identified units in Oxia Planum [1] to determine model surface ages, both with and without secondary craters removed. We then merged the original catalogue of small impact craters [5, 6], with craters with diameters &gt;1 km [7] in a larger (1.2 x106 km2) ‘context study region’. We used the same methods to identify possible primary and secondary craters, and produced a crater size density map of possible secondary craters. ResultsWe separate our results into (1) the identification and analysis of secondary craters, and (2) the implications for model ages in Oxia Planum.Secondary Craters. Of the impact craters in the smaller Oxia Planum study region, we classified 176,927 (46.4%) as primary craters, with 204,657 (53.6%) classified as secondary craters. The number of possible secondary craters has been revised down from our previous results [8]. We identified at least 13 separate clusters of craters that occur in cone shapes, with each cluster typically up to 40 km long and 20 km wide at the distal ends. These cones are oriented radially away from Mojave crater, with the median direction being 225°, similar to the median direction (222°) to Mojave crater. The cones show a distinctive size distribution of craters, with larger craters limited to the proximal (apex) region, with a gradual transition to smaller craters in the distal zone. The cones in our Oxia Planum study region are located at distances of ~700 to 930 km from Mojave. The larger, context study region contains 2,877,811 impact craters, ranging in size from 29 m to 54.4 km [5-7]. We classified 1,356,995 (47.2%) as primary craters, with 1,520,816 (52.8%) classified as secondary craters. We identify a further 13 cone-shaped clusters of secondary craters in the context study region, with ranges ~275 – 500 km from Mojave.Figure 1. (A) Possible primary (red) and secondary (green) impact craters in our Oxia Planum study region. (B) Secondary crater size density map of same region. EMRF 1s (grey) and 3s (black) ellipse ranges are shown. Model Surface Ages. The removal of secondary craters from CSFD studies does not affect the model surface age of the phyllosilicate units in Oxia Planum. We derive a model surface age of 3.9 Ga for the Noachian layered clay-bearing unit (lNc) of [1] using all our craters, and an identical age when using just our primary craters. This similarity is due to the lack of secondary craters at larger diameters. ImplicationsOur results suggest that there are extensive secondary impact craters in Oxia Planum, with ~4000 secondaries within the EMRF 3s ellipse pattern. It is therefore likely that EMRF will encounter secondary craters during surface operations. The orientation of cone-shaped clusters of small craters indicates that the majority of secondaries are sourced from the Mojave impact crater, although larger, older secondary craters from other sources are also present. Given that the Mojave impact is estimated to have occurred 10.1 Ma [3], these secondaries can be used as absolute stratigraphic markers throughout Oxia Planum, particularly in quantifying the rate of recent and active surface processes. These secondary craters will also be important for target prioritization during in situ studies.

This work presents the assembly of 48 papers, representing74 differentcompounds and blends, into a machine-readable database of nonaqueousproton-conducting materials. SMILES was used to encode the chemicalstructures of the molecules, and we tabulated the reported protonconductivity, proton diffusion coefficient, and material compositionfor a total of 3152 data points. The data spans a broad range of temperaturesranging from −70 to 260 °C. To explore this landscapeof nonaqueous proton conductors, DFT was used to calculate the protonaffinity of 18 unique proton carriers. The results were then comparedto the activation energy derived from fitting experimental data tothe Arrhenius equation. It was found that while the widely recognizedpositive correlation between the activation energy and proton affinitymay hold among closely related molecules, this correlation does notnecessarily apply across a broader range of molecules. This work servesas an example of the potential analyses that can be conducted usingliterature data combined with emerging research tools in computationand data science to address specific materials design problems.

We describe properties of 2-adic valuation trees associated to depressed cubic polynomials. By doing so, we provide a criterion for the solvability of a depressed cubic equation and the number of solutions over some domains of $$\mathbb{Q}_2$$ . This leads to the locality of the solutions of the depressed cubic equation over $$\mathbb{Q}_2$$ . We also present an example illustrating how the dynamics of depressed cubic polynomials with infinite tree branches may fail to be topologically transitive (i.e., dense) over the set $$\mathbb{Z}_2$$ .