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The LIM-domain-only protein LMO2 and its binding partner LDB1 are differentially required for class switch recombination

Proceedings of the National Academy of Sciences Beibei Yang, Yao Guo, Lilong Liu et al. Jan 28, 2025 DOI: 10.1073/pnas.2412376122

The LIM-domain-only protein LMO2 interacts with LDB1 in context-dependent multiprotein complexes and plays key roles in erythropoiesis and T cell leukemogenesis, but whether they have any roles in B cells is unclear. Through a CRISPR/Cas9-based loss-of-function screening, we identified LMO2 and LDB1 as factors for class switch recombination (CSR) in murine B cells. LMO2 contributes to CSR at least in part by promoting end joining of DNA double-strand breaks (DSBs) and inhibiting end resection. Although LDB1 stabilizes LMO2 proteins, it is not required for end joining but functions as a positive regulator of AID transcription independent of LMO2, and this function of LDB1 requires its dimerization domain. Moreover, LDB1 directly binds to and promotes the looping of the AID promoter to upstream enhancers through dimerization. Our study revealed the mechanistically separated roles of LMO2 and LDB1 in different steps of CSR for antibody diversification.

Association of preoperative body mass index with postoperative complications and survival for patients with gastric cancer: A systematic review and meta-analysis

PLoS ONE Zhenzhen Li, Lili Cui, Jing Sun et al. Jan 28, 2025 DOI: 10.1371/journal.pone.0317985

Objective The relationship among body mass index (BMI), postoperative complications, and clinical outcomes in patients undergoing gastrectomy for gastric cancer remains unclear. This study aimed to evaluate this association using a meta-analysis. Method We conducted a systematic search of the PubMed, Embase, and Cochrane Library databases up to February 25, 2024. Patients were classified into underweight (<18.5 kg/m2), normal weight (18.5–25.0 kg/m2), and overweight (≥25.0 kg/m2) groups based on BMI categories. Meta-analysis was performed using a random-effects model. Additionally, exploratory sensitivity and subgroup analyses were performed. Results Twenty-two studies involving 41,144 patients with gastric cancer were included for quantitative analysis. Preoperative underweight (odds ratio [OR]: 1.26; 95% confidence interval [CI]: 1.03–1.55; P = 0.024) and overweight (OR: 1.19; 95%CI: 1.09–1.30; P <0.001) were associated with an increased risk of postoperative complications. Furthermore, preoperative underweight was associated with poorer overall survival (hazard ratio [HR]: 1.40; 95%CI: 1.28–1.53; P <0.001), whereas preoperative overweight was associated with better over-survival (HR: 0.82; 95%CI: 0.73–0.91; P <0.001). Furthermore, preoperative underweight was not associated with disease-free survival (HR: 1.48; 95%CI: 0.97–2.26; P = 0.069), whereas preoperative overweight was associated with longer disease-free survival (HR: 0.80; 95%CI: 0.70–0.91; P = 0.001). In terms of specific postoperative complications, preoperative underweight was associated with an increased risk of septic shock (OR: 3.40; 95%CI: 1.26–9.17; P = 0.015) and a reduced risk of fever (OR: 0.39; 95%CI: 0.18–0.83; P = 0.014). Preoperative overweight was associated with an increased risk of wound infections (OR: 1.78; 95%CI: 1.08–2.93; P = 0.023), intestinal fistula (OR: 5.23; 95%CI: 1.93–14.21; P = 0.001), arrhythmia (OR: 6.38; 95%CI: 1.70–24.01; P = 0.006), and pancreatic fistula (OR: 3.37; 95%CI: 1.14–9.96; P = 0.028). Conclusion This study revealed that both preoperative underweight and overweight status were associated with an increased risk of postoperative complications. Moreover, the postoperative survival outcomes were significantly better in overweight compared to that of underweight patients. Trial registration Registration: INPLASY202480004.

A three-stage plasma model based on one-way coupling of plasma dynamics, ionic motion, and fluid flow: Application to DBD plasma actuators

Journal of Applied Physics G. P. Vafakos, P. K. Papadopoulos, P. Svarnas Jan 28, 2025 DOI: 10.1063/5.0242676

The scope of this paper is to present a comprehensive approach for simulating low-temperature atmospheric dielectric barrier discharge plasmas. The proposed methodology categorizes the primary physical phenomena: (i) discharge dynamics, (ii) ionic motion, and (iii) fluid flow, according to their respective time scales and simulates each independently. This allows for the use of distinct solution procedures tailored to each of the three stages of the problem. Such separation offers significant flexibility in choosing appropriate models and numerical schemes for each stage, enabling the simulation of complex geometries and large-scale applications without the excessive computational costs associated with a monolithic approach. As a case study, we apply the proposed algorithm to the surface dielectric barrier discharge plasma actuator for flow control, which is powered by alternating high voltages. The algorithm successfully described the actuator’s behavior while maintaining low computational cost. Additionally, a parametric study is conducted to examine the effect of key input parameters on the generated electrohydrodynamic force and the resulting velocity. Finally, an overall assessment of the three-stage model is provided, highlighting its efficiency and accuracy.

Coding relationship links RNA G-quadruplexes and protein RGG motifs in RNA-binding protein autoregulation

Proceedings of the National Academy of Sciences Marlene Adlhart, Daniel Hoffmann, Anton A. Polyansky et al. Jan 28, 2025 DOI: 10.1073/pnas.2413721122

RNA G-quadruplexes (rG4s), the four-stranded structures formed by guanine-rich RNA sequences, are recognized by regions in RNA-binding proteins (RBPs) that are enriched in arginine-glycine repeats (RGG motifs). Importantly, arginine and glycine are encoded by guanine-rich codons, suggesting that some RGG motifs may both be encoded by and interact with rG4s in autogenous messenger RNAs (mRNAs). By analyzing transcriptome-wide rG4 datasets, we show that hundreds of RGG motifs in humans are at least partly encoded by rG4s, with an increased incidence for longer RGG motifs (~10 or more residues). Using randomized genetic codes, we demonstrate that the rG4/RGG coding relationship derives from the universal genetic code’s structure. Moreover, we show that proteins, which contain RGG motifs encoded by experimentally detected rG4s, are significantly enriched in RNA binding relative to all RGG-containing proteins. Finally, using enhanced crosslinking and immunoprecipitation (eCLIP) data, we identify several prominent RBPs, including FUS, FMRP, and G3BP1, which interact with autogenous mRNAs in regions where RGG motifs are encoded by rG4s. Our results define a physically realistic mechanism behind autogenous mRNA/protein interactions that is hardwired in the genetic code structure and may contribute to the establishment of autoregulatory feedback loops in the cell.

GorillaFACS: The Facial Action Coding System for the Gorilla spp.

PLoS ONE Catia Correia-Caeiro, Raquel Costa, Misato Hayashi et al. Jan 28, 2025 DOI: 10.1371/journal.pone.0308790

The Facial Action Coding System (FACS) is an objective observation tool for measuring human facial behaviour. It avoids subjective attributions of meaning by objectively measuring independent movements linked to facial muscles, called Action Units (AUs). FACS has been adapted to 11 other taxa, including most apes, macaques and domestic animals, but not yet gorillas. To carry out cross species studies of facial expressions within and beyond apes, gorillas need to be included in such studies. Hence, we developed the GorillaFACS for the Gorilla spp. We followed similar methodology as previous FACS: First, we examined the facial muscular plan of the gorilla. Second, we analysed gorilla videos in a wide variety of contexts to identify their spontaneous facial movements. Third, we classified the individual facial movements according to appearance changes produced by the corresponding underlying musculature. A diverse repertoire of 42 facial movements was identified in the gorilla, including 28 AUs and 14 Action Descriptors, with several new movements not identified in the HumanFACS. Although some of the movements in gorillas differ from humans, the total number of AUs is comparable to the HumanFACS (32 AUs). Importantly, the gorilla’s range of facial movements was larger than expected, suggesting a more relevant role in social interactions than what was previously assumed. GorillaFACS is a scientific tool to measure facial movements, and thus, will allow us to better understand the gorilla’s expressions and communication. Furthermore, GorillaFACS has the potential be used as an important tool to evaluate this species welfare, particularly in settings of close proximity to humans.

Correlation between ferroelectricity and torsional motion of acetyl groups in tris(4-acetylphenyl)amine observed by muon spin relaxation

Journal of Applied Physics J. G. Nakamura, M. Hiraishi, H. Okabe et al. Jan 28, 2025 DOI: 10.1063/5.0247652

It is demonstrated by muon spin relaxation and resonance experiments that the switchable spontaneous polarization of the organic ferroelectric compound tris(4-acetylphenyl)amine is governed by the local molecular dynamics of the acetyl group. The implanted muon forms paramagnetic states, which exhibit longitudinal spin relaxation due to the fluctuation of hyperfine fields exerted from unpaired electrons. The first-principle density functional theory calculations indicate that these states are muonated radicals localized at the phenyl group and on the carbon/oxygen of the acetyl group, thereby suggesting that the spin relaxation is dominated by the random torsional motion of an acetyl group around the C–C bond to the phenyl group. The stepwise change in the relative yield of radicals at T0≈350 K and the gradual increase in the spin relaxation rate with temperature (T) indicate that the torsional motion is significantly enhanced by thermal excitation above T0. This occurs concomitantly with the strong enhancement in the atomic displacement parameter of oxygen in the acetyl group (which is non-linear in T), indicating that it is the local molecular motion of the acetyl groups that drives the structural transition.

Expert navigators deploy rational complexity–based decision precaching for large-scale real-world planning

Proceedings of the National Academy of Sciences Pablo Fernandez Velasco, Eva-Maria Griesbauer, Iva K. Brunec et al. Jan 28, 2025 DOI: 10.1073/pnas.2407814122

Efficient planning is a distinctive hallmark of intelligence in humans, who routinely make rapid inferences over complex world contexts. However, studies investigating how humans accomplish this tend to focus on naive participants engaged in simplistic tasks with small state spaces, which do not reflect the intricacy, ecological validity, and human specialization in real-world planning. In this study, we examine the street-by-street route planning of London taxi drivers navigating across more than 26,000 streets in London (United Kingdom). We explore how planning unfolded dynamically over different phases of journey construction and identify theoretic principles by which these expert human planners rationally precache decisions at prioritized environment states in an early phase of the planning process. In particular, we find that measures of path complexity predict human mental sampling prioritization dynamics independent of alternative measures derived from the real spatial context being navigated. Our data provide real-world evidence for complexity-driven remote state access within internal models and precaching during human expert route planning in very large structured spaces.

Electroconvulsive shock and transcranial magnetic stimulation do not alter the survival or spine density of adult-born striatal neurons

PLoS ONE Tara Gaertner, Tian Rui Zhang, Baran Askari et al. Jan 28, 2025 DOI: 10.1371/journal.pone.0316717

Adult neurogenesis has most often been studied in the hippocampus and subventricular zone-olfactory bulb, where newborn neurons contribute to a variety of behaviors. A handful of studies have also investigated adult neurogenesis in other brain regions, but relatively little is known about the properties of neurons added to non-canonical areas. One such region is the striatum. Adult-born striatal neurons have been described in both rodents and humans, but the regulation of these neurons is poorly understood. Since striatal dysfunction occurs in Parkinson’s disease, which is amenable to neurostimulation therapies, we investigated whether electroconvulsive shock (ECS) or transcranial magnetic stimulation (rTMS) modulate neuroplasticity of adult-born striatal neurons. Adult-born cells were labelled in transgenic mice and 8 days later mice were given 10 stimulations over the course of 3 weeks. Adult-born striatal neurons were consistently observed in all groups. Their dendritic morphology and expression of DARPP32 and NeuN indicated a medium spiny neuron phenotype. However, neither ECS nor rTMS altered the number of new neurons, and both treatments also had no effect on the density of dendritic spines compared to unstimulated controls. These results suggest that neither ECS nor rTMS alter early neuronal survival or morphological plasticity at postsynaptic sites in the striatum.

Influence of substrate orientation and pre-annealing treatment on the metal–insulator transition in V2O3 films: Insights from Al2O3<i>r</i>, <i>a</i>, <i>c</i>, and <i>m</i>-plane substrates

Journal of Applied Physics Muhammad Taha Sultan, Kristina Ignatova, Snorri T. Ingvarsson et al. Jan 28, 2025 DOI: 10.1063/5.0245429

We investigate the structural and metal–insulator transition (MIT) behavior of epitaxial V2O3 films fabricated by reactive direct current magnetron sputtering on r, a, c, and m-plane Al2O3 substrates, in both as-received and annealed states. Characterization of MIT of the V2O3 films grown on annealed substrates demonstrated significant changes in observed MIT properties, i.e., r-plane films showed ≈2 order increase in transition magnitude, m-plane ≈6 orders, and c-plane films exhibited a reduction of ≈3 orders, compared to un-annealed substrates, whereas for V2O3 on annealed a-plane, it revealed a shift in the transition to higher values, with reduction in hysteresis width. Structural characterization conducted via x-ray diffraction and atomic force microscopy revealed a reduction in out-of-plane compressive strain for annealed substrates, along with decreased lateral grain size. Additionally, the correlation between the V2O3 MIT and its underlying structural phase transition was verified by temperature-dependent x-ray diffraction analysis. These findings highlight the role of substrate orientation and pre-annealing in tuning the MIT behavior of V2O3 films grown on the Al2O3 substrate.

Governing in the face of a global crisis: When do voters punish and reward incumbent governments?

Proceedings of the National Academy of Sciences Raymond M. Duch, Peter Loewen, Thomas S. Robinson et al. Jan 28, 2025 DOI: 10.1073/pnas.2405021122

The recent COVID-19 pandemic offers a rare opportunity to understand how citizens attribute responsibility for governments’ responses to unanticipated negative—and in this case, systemic—exogenous shocks. Classical accounts of responsibility are complicated when crises are pervasive, involve multiple valence dimensions, and where individuals can make relative assessments of performance. We fielded a conjoint experiment in 16 countries with 22,147 respondents. In this experiment, subjects made re-election decisions regarding 178,184 randomly assigned incumbent profiles. We find that incumbents’ performance along both health and economic dimensions drives these hypothetical reelection decisions. Using machine learning techniques, we find only muted heterogeneity in the magnitude and distribution of these treatment effects. This result suggests that these widely reported performance signals have consistent political effects across countries. In a complementary analysis, we also find that subjects’ intentions to vote for incumbent governments are positively correlated with subjective and relative evaluations of the government’s pandemic performance, along both health and economic dimensions. These results provide consistent evidence that evaluations of pandemic performance matter politically.

The liminal space between hope and grief: The phenomenon of uncertainty as experienced by people living with relapsing-remitting multiple sclerosis

PLoS ONE Eva C. van Reenen, Inge A. M. van Nistelrooij, Leo H. Visser et al. Jan 28, 2025 DOI: 10.1371/journal.pone.0315501

Background People with the chronic disease Multiple Sclerosis are subjected to different degrees of profound uncertainty. Uncertainty has been linked to adverse psychological effects such as feelings of heightened vulnerability, avoidance of decision-making, fear, worry, anxiety disorders, and even depression. Research into Multiple Sclerosis has a predominant focus on the scientific, practical, and psychosocial issues of uncertainty. In comparison, existential uncertainty has been under-researched, even though it might pose a greater burden to those experiencing it. Objective To understand the lived experience of uncertainty for people living with relapsing-remitting Multiple Sclerosis. Methods This study followed a phenomenological research design, employing elements of both the Reflective Lifeworld Approach and Phenomenology of Practice. Seventeen people with a recent (&lt;1 year) diagnosis of relapsing-remitting Multiple Sclerosis were included. In-depth interviews were conducted immediately after inclusion. Results The lived experience of uncertainty can be described as a stumbling motion across the liminal space between hope and grief while dealing with oscillating feelings of unrest concerning the body, self, and others. The following four constituents further illuminate the meaning of the phenomenon: Having to constantly (re)define unfamiliar and intangible bodily changes on one’s own; Unsteady navigating amidst a destabilization of the imagined life; Relating to others as a source of, mirror or buffer for uncertainty; Going through overwhelming fears and worries while clinging to one’s own logic. Conclusion Adding to existing qualitative and phenomenological research into MS and theories on uncertainty, this study portrays uncertainty as a multifaceted experience. The findings imply the need for a continuous attunement of healthcare practitioners to the expectations, fears, avoidance techniques, and other uniquely personal circumstances of people with Multiple Sclerosis.

Fine texture Lambertian electromagnetic metasurface generates background blending stealth effect in radar vision

Journal of Applied Physics Honglin Yuan, Yingjian Sun, Yixing Huang et al. Jan 28, 2025 DOI: 10.1063/5.0246822

The emergence of diffuse scattering metasurfaces offers the electromagnetic scattering stealth mechanism. However, the background blending stealth effect in radar vision induced by diffuse scattering metasurface has not been specially investigated. Here, a background blending Lambertian diffusive reflective metasurface for imaging radar stealth is designed by electromagnetic dispersion engineering. Compared to a conventional metasurface, the Lambertian metasurface achieves more uniform beam dispersion over a broad frequency range without significant main lobe formation at any frequency point, which provides ways for background fusion stealth. For conceptual validation, a metallic flat plate, coded metasurface, and Lambertian metasurface are fabricated and their radar images are obtained by two-dimensional imaging scanning measurement. As anticipated, the Lambertian metasurface notably alters the imaging edge characteristics in the radar images, effectively concealing the contours of the covered area. This work provides a wideband design method of the coded metasurface, which provides a new idea for designing stealth material and structures from the perspective of radar imaging and is immensely helpful for practical application in jamming recognition stealth of coding metasurfaces.

Enhancing drug solubility through competitive adsorption on silica nanosurfaces with ultrahigh silanol densities

Proceedings of the National Academy of Sciences Zhuo Xu, Changliang Zhu, Hongchuan Shen et al. Jan 28, 2025 DOI: 10.1073/pnas.2423426122

We develop a technology based on competitive adsorption between drug molecules and water, specifically designed to address the critical issue of poor drug solubility. By specially engineering silica nanosurfaces with ultrahigh densities of silanol, we significantly enhance their affinity for both drug molecules and water, with a notably greater increase in water affinity. Such surfaces can effectively adsorb a variety of drug molecules under dry conditions. Upon exposure to water, these surfaces preferentially bind to water molecules, initiating a competitive adsorption process with the drug molecules. This competitive process turns water molecules from obstacles into catalysts for drug dissolution by actively displacing drug molecules from the surface, causing their rapid desorption and potentially enhancing their solubility by two to three orders of magnitude. The method is general, applicable to a wide array of drugs, stable for long-time storage, cost-effective, and scalable for mass production. Consequently, it has the potential to emerge as a next-generation platform for drug formulation and delivery.

Evidence that flocking behavior is rewarded by singing, flock mates, and mu opioid receptors in the nucleus accumbens

PLoS ONE Alyse N. Maksimoski, Taviah A. Levenson, Changjiu Zhao et al. Jan 28, 2025 DOI: 10.1371/journal.pone.0318340

It has been proposed that social groups are maintained both by reward resulting from positive social interactions and by the reduction of a negative state that would otherwise be caused by social separation. European starlings, Sturnus vulgaris, develop strong conditioned place preferences for places associated with the production of song in flocks outside the breeding season (gregarious song) and singers are motivated to rejoin the flock following removal. This indicates that the act of singing in flocks is associated with a positive affective state and raises the possibility that reward induced by song in flocks may play a role in flock maintenance. The goal of this study was to begin to test this hypothesis. We found that birds that sang full songs developed stronger conditioned place preferences than non-singing birds for places associated with flock mates, indicating that singers find the presence of flock mates to be rewarding. Regardless of song rate, the presence of flock mates also induced analgesia (a reflection of the reduction of a negative state). This form of analgesia has been shown to be an indirect measure of opioid release, suggesting that the presence of flock mates may induce opioid-mediated reward. Consistent with this possibility, the numbers of mu opioid receptor immunolabeled cells in the nucleus accumbens correlated positively with measurements of gregarious song and other social behaviors. Results suggest that both gregarious song and social contact promote flock cohesion and that opioids released onto mu opioid receptors in the nucleus accumbens may play an important role.

Outer space cultivated regular eutectic cells with anomalous internal microstructures for rapidly solidifying Zr50V50 hypereutectic alloy

Journal of Applied Physics Haipeng Wang, Chenhui Zheng, Liang Hu et al. Jan 28, 2025 DOI: 10.1063/5.0245520

The special type of regular eutectic cells with anomalous internal microstructures may improve advanced alloy performances but is difficult to cultivate on the ground because of the coupled effect between cell growth dynamics and strong natural convection. Here, outer space experiments aboard the China Space Station were designed to explore and cultivate this kind of special eutectic cells in the Zr50V50 hypereutectic alloy. It was found that the space environment under 10−5 g0 microgravity brought in much more and smaller eutectic cells on the alloy surface, in particular, the alloy droplet solidified at 160 K undercooling displayed priority growth of eutectic cells with anomalous internal microstructures. This was controlled by the more nuclei within the floating droplet resulting from much lower flow velocity, much weaker convection, and less uniform temperature distribution, as revealed by the thermophysical properties measured via space-based electrostatic technique. Furthermore, a critical anomalous eutectic transition undercooling range of 102–110 K was ascertained by the space interface migration dynamics. Our findings contribute to the method and principle of how to apply the outer space environment to cultivate extraordinary microstructures within eutectic alloys.

A carnitine transporter at the blood–brain barrier modulates sleep via glial lipid metabolism in <i>Drosophila</i>

Proceedings of the National Academy of Sciences Ashley Avila, Ava S. Lewandowski, Yongjun Li et al. Jan 28, 2025 DOI: 10.1073/pnas.2421178122

To regulate brain function, peripheral compounds must traverse the blood–brain barrier (BBB), an interface between the brain and the circulatory system. To determine whether specific transport mechanisms are relevant for sleep, we conducted a BBB-specific inducible RNAi knockdown (iKD) screen for genes affecting sleep in Drosophila . We observed reduced sleep with knockdown of solute carrier CG6126 , a carnitine transporter, as determined by isotope flux. Our findings suggest that CG6126 regulation of sleep is through the role of the carnitine shuttle in regulating fatty acid metabolism as lipid droplets accumulate in the brains of CG6126 BBB iKD flies. Knocking down mitochondrial carnitine transferases in non-BBB glial cells mimicked the reduced sleep of the CG6126 BBB iKD flies, while bypassing the necessity of carnitine transport with dietary medium-chain fatty acids or palmitoylcarnitine rescued sleep. We propose that carnitine transport via CG6126 promotes brain fatty acid metabolism necessary for maintaining sleep.

The international trial of nasal oxygen therapy after cardiac surgery (NOTACS) in patients at high risk of postoperative pulmonary complications: Economic evaluation protocol and analysis plan

PLoS ONE Siddesh Shetty, Melissa Duckworth, Richard Norman et al. Jan 28, 2025 DOI: 10.1371/journal.pone.0311861

Introduction High-Flow Nasal Therapy (HFNT) is an innovative non-invasive form of respiratory support. Compared to standard oxygen therapy (SOT), there is an equipoise regarding the effect of HFNT on patient-centred outcomes among those at high risk of developing postoperative pulmonary complications after undergoing cardiac surgery. The NOTACS trial aims to determine the clinical and cost-effectiveness of HFNT compared to SOT within 90 days of surgery in the United Kingdom, Australia, and New Zealand. This protocol describes the methods and analyses planned for economic evaluation embedded within the ongoing NOTACS trial. Methods and analysis The economic evaluation will identify, measure and value resources and health outcomes in both trial arms and compare changes in costs with ‘days alive and at home’ and EQ-5D-5L quality adjusted life years (QALYs) from the perspective most relevant to the decision-making country. Results from pooling data across the trial will use health and social care sector perspective. All patient-specific data including hospital/community care and health outcomes will be collected prospectively. Unit costs will be sourced from national, published or local data. Missing data will be assessed, with values replaced depending on assumed mechanism of missingness, and impact of replacement on cost-effectiveness assessed. Costs and outcomes by trial arm will be presented as components and totals per patient using a range of descriptive statistics. Regression models for costs and effects will account for patient characteristics, quality of life and health service utilization at baseline. Uncertainty in parameters, sampling and heterogeneity will be addressed through deterministic, probabilistic and subgroup analyses to assess the impact of varying methods and assumptions for costs, outcomes and approaches used in base-case analysis. Results will be interpreted using recommended national cost-effectiveness thresholds. Registration details The study is registered with ISRCTN (ISRCTN14092678) on 13/05/2020. ISRCTN is a primary registry of the WHO ICTRP network and includes all items from the WHO Trial Registration data set.

Investigation of (mis-)orientation in zincblende GaN grown on micro-patterned Si(001) using electron backscatter diffraction

Journal of Applied Physics Dale M. Waters, Bethany Thompson, Gergely Ferenczi et al. Jan 28, 2025 DOI: 10.1063/5.0244438

We present the application of electron backscatter diffraction (EBSD) as a technique for characterizing wurtzite (wz) and zincblende (zb) polytypes of GaN grown upon micropatterned Si (001) substrates. The Si substrate is etched to create parallel V-shaped grooves with opposing {111} facets before the deposition of GaN. EBSD revealed that wz-GaN growth fronts initially form on the {111} Si facets before undergoing a transition from a wurtzite to zincblende structure as the two growth fronts meet. Orientation analysis of the GaN structures revealed that the wz-GaN growth fronts had different growth orientations but shared the same crystallographic relationship with the zb-GaN such that ⊥{303¯8}wz∥⟨110⟩zb, ⟨112¯0⟩wz∥⟨110⟩zb, and ⊥{303¯4}wz∥⟨001⟩zb. Furthermore, the crystallographic relationship, {0001}wz-GaN∥{111}zb-GaN∥{111}Si, and alignment of the wz- and zb-GaN with respect to the Si substrate was investigated. The two wz-GaN ⟨0001⟩ growth directions were expected to coalesce at an angle of 109.5°; however, measurements revealed an angle of 108°. The resultant misalignment of 1.5° induces misorientation in the zb-GaN crystal lattice. While the degree of misorientation within the zb-GaN lattice is low, &amp;lt;1°, the zb-GaN lattice is deformed and bends toward the wz-GaN interfaces about the specimen direction parallel to the length of the V-groove. Further EBSD measurements over larger areas of the sample revealed that these results were consistent across the sample. However, it was also revealed that additional factors induce changes in the orientation of the zb-GaN lattice, which may relate to the initial growth conditions of the zb-GaN.

Behavioral nudges prevent loan delinquencies at scale: A 13-million-person field experiment

Proceedings of the National Academy of Sciences Robert Kuan, Kristin Blagg, Benjamin L. Castleman et al. Jan 28, 2025 DOI: 10.1073/pnas.2416708122

Americans collectively hold over $1.6 trillion in student loan debt, and over the last decade millions of borrowers have defaulted on loans, with serious consequences for their financial health. In a 13-million-person field experiment with the U.S. Department of Education, we tested the effectiveness of different email interventions to inform borrowers about alternative repayment options after a missed loan payment. Our interventions tested whether sending monthly behaviorally-informed emails, providing follow-up reminders, framing benefits in percentage (vs. dollar) terms, and providing just one recommended action step at a time (vs. two) affected borrower outcomes. We find that i) behaviorally-informed emails reduce estimated 60-d delinquencies by 0.42 pp, ii) reminders boost the efficacy of such emails by 0.57 pp, iii) describing potential savings in percentage terms is more effective than describing these benefits in dollar terms, reducing estimated delinquencies by 0.14 pp, and iv) encouraging two actions (i.e., enrollment in income-driven repayment plans and auto debit programs) repeatedly across two emails is marginally more effective than encouraging one action at-a-time across two emails, reducing estimated delinquencies by 0.05 pp. Overall, if scaled to all 13-million borrowers in our experiment, we estimate that our best-performing intervention would have averted approximately 79,800 60-d delinquencies. Our findings i) highlight the benefits of describing potential savings in percentage terms, which may magnify perceived savings for recipients, ii) underscore the risks of oversimplification, and iii) demonstrate that nudges can be an effective, low-cost complement to other policies for reducing delinquencies and supporting borrowers with student loan debt.

Smart home technology to support engagement in everyday activities while ageing: A focus group study with current and future generations of older adults

PLoS ONE William Son Galanza, Jens Offerman, Sofi Fristedt et al. Jan 28, 2025 DOI: 10.1371/journal.pone.0317352

Despite the potential of smart home technologies (SHT) to support everyday activities, the implementation rate of such technology in the homes of older adults remains low. The overall aim of this study was to explore factors involved in the decision-making process in adopting SHT among current and future generations of older adults. We also aimed to identify and understand barriers and facilitators that can better support older adults’ engagement in everyday activities. Focus group discussions were used to explore the perspectives of people from diverse age groups (30–39, 50–59, and 70-79-year-olds). Three focus groups met twice at a lab designed as a two-room home equipped with SHT. Our findings revealed that the participants’ decision-making process for adopting SHT involved designs that must be adapted to the changing physical abilities and diverse needs of users. Some conditions, such as ideas for re-invention, were identified after the integration of SHT. Concerns about reliability, complicated interfaces, and value to the user influenced the decision to adopt SHT, highlighting the importance of these factors for successful implementation. Some participants did not fully understand what SHT is nor perceive its benefits, but they expressed a desire to acquire the skills and knowledge to operate SHT. Furthermore, participants desired SHT that can support an active lifestyle. The perceived advantages of SHT include enhancing the sense of security and safety, which can facilitate engagement in everyday activity. Some participants experienced a positive impact on quality of life, related to comfortable living with the implementation of SHT. Adults across age groups perceive that SHT can enhance engagement in everyday activity and the sense of safety and security. However, it is essential to identify solutions for better usability. More collaborative efforts involving diverse stakeholders are vital to bridge the disconnect between SHT design and users’ needs and preferences.