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Lomer (L) and Lomer-Cottrell (LC) dislocations have long been considered to be central to work hardening in face-centered cubic (FCC) metals and alloys. These dislocations act as barriers of motion for other dislocations, and can serve as sites for twin nucleation. Recent focus on multicomponent concentrated FCC solid solution alloys has resulted in many reported observations of LC dislocations. While these and L dislocations are expected to have a role in the mechanical behavior of these alloys, little is understood about how variations in composition and associated fault energies change the response of these dislocations under stress. We present atomistic simulations of L and LC dislocations in a model Cu-Ni system and find that changes in composition and applied stress conditions result in a wide variety of responses, including changes in core configuration and (100) glide. The results are compared to and extend previous literature related to the nature of L/LC core structures and how they vary with respect to intrinsic materials properties and stress states. This study also provides insights into mechanisms such as twin nucleation that could have important implications for work hardening in FCC solid-solution alloys.

What are the roles of central and peripheral vision in human scene recognition? Larson and Loschky (2009) showed that peripheral vision contributes more than central vision in obtaining maximum scene recognition accuracy. However, central vision is more efficient for scene recognition than peripheral, based on the amount of visual area needed for accurate recognition. In this study, we model and explain the results of Larson and Loschky (2009) using a neurocomputational modeling approach. We show that the advantage of peripheral vision in scene recognition, as well as the efficiency advantage for central vision, can be replicated using state-of-the-art deep neural network models. In addition, we propose and provide support for the hypothesis that the peripheral advantage comes from the inherent usefulness of peripheral features. This result is consistent with data presented by Thibaut, Tran, Szaffarczyk, and Boucart (2014), who showed that patients with central vision loss can still categorize natural scenes efficiently. Furthermore, by using a deep mixture-of-experts model ("The Deep Model," or TDM) that receives central and peripheral visual information on separate channels simultaneously, we show that the peripheral advantage emerges naturally in the learning process: When trained to categorize scenes, the model weights the peripheral pathway more than the central pathway. As we have seen in our previous modeling work, learning creates a transform that spreads different scene categories into different regions in representational space. Finally, we visualize the features for the two pathways, and find that different preferences for scene categories emerge for the two pathways during the training process.

In this study, we develop a new theoretical model for the quantitative prediction of atomic diffusion in a crystalline material. Concentration of the solute atom is expressed by a probability density function whose time evolution is governed by the Fokker–Planck equation. The stochastic differential equation describes the two competitive processes; drift motion by the stress field and thermal diffusion by the Brownian motion. Non-singular stress field by a lattice defect is obtained from nonlinear elastoplasticity on Riemann–Cartan manifold. Numerical integration is conducted using the finite difference method which satisfies the numerical stability criteria. Present analysis demonstrates the formation of Cottrell atmosphere around a straight edge dislocation. The probability density reaches to an equilibrium distribution and the time evolution satisfies the Cottrell’s theoretical prediction quantitatively. The mean diffusion path is predicted from the streamline which includes the surface effects. We also demonstrate the dislocation pipe diffusion, i.e., accelerated diffusion along a dislocation line.

Mit der Einbindung von Fotografien in literarische Texte entstehen multimodale Texte, bei denen sprachliche und nicht-sprachliche Darstellungsmodi zusammenspielen. Die Kombination von Fotografie und Literatur erzeugt so einen intermedialen Spannungsraum; auf den ersten Blick scheint die Fotografie dem fiktionalen Charakter literarischer Texte entgegenzustehen; jedoch können Fotos mit ihren Realitätsbezügen gleichsam spielen, diese als Fiktion entlarven und so Teil der Fiktion selbst werden. Insofern Fotografien Vergangenes festhalten und konservieren, treten sie zudem häufig in literarischen Erinnerungs- und Gedächtnistexten auf. Ein Beispiel dafür ist der Kinderroman Der unvergessene Mantel (2012) von Frank Cottrell Boyce. In das Konstrukt einer fiktiven autobiografischen Erinnerungsgeschichte sind Polaroid-Fotos montiert, die ein gezieltes Verwirrspiel erzeugen und die Leser*innen zu folgenden Fragen veranlassen: Was ist Fakt und was Fiktion? Was ist wahr und was gefaket? Dass der Autor im Nachwort auf ein reales Migrationsschicksal Bezug nimmt, zeigt das Ineinander fiktiver, pseudo-realer und realer Elemente und macht den Roman auch thematisch zu einem geeigneten Gegenstand, um SchülerInnen anzuleiten, die mediale Konstruiertheit im Verhältnis von Fakt, Fake und Fiktion wahrzunehmen und zu reflektieren. Abstract (english): Facts, fakes and fiction. The construction of reality as a combination of photographic images and text in the multimodal novel The unforgotten Coat by Frank Cottrell Boyce Multimodal novels are characterized by word-based storytelling integrating visual images and semiotic languages. Photographic images, however, seem to be the opposite of fictional worlds because they are supposed to be realistic and authentic. But are they really realistic or do they fake reality? The multimodal novel The unforgotten coat by Frank Cottrell Boyce uses over 20 polaroid photos to play hide and seek in the intermediate space between photos and text. By pointing a camera on it, Liverpool is turning into Mongolia and the reader is shown and told the destiny of a young refugee. The stylistic devices between two media reveal the sign of medial constructions and may support students‘ capacity to distinguish between fiction, fake and reality and to reflect their mixing.

Online instructional delivery has always been viewed as beneficial due to its flexibility in settings and times, but the COVID-19 pandemic produced an essential need for the ability to engage in learning without direct contact with others. For students with Autism Spectrum Disorder and Intellectual Disability (ASD and ID) who have extensive support needs, developing the skills required to engage with online content is critical for utilizing and interacting with distance learning platforms and resources. Using a visual task analysis, least-to-most prompting, and reinforcement, students with ASD and ID can be taught to use technological devices for virtual instruction without adult support. By teaching students to access and use point-of-view video modeling for online instructional delivery, teachers can facilitate skills their students need to access evidence-based practices and meet diverse learning goals and objectives.

The author has been asked to respond to Lodge, Hansen, and Cottrell's recent (2015) paper in this journal and they have done a very thorough and scholarly job of dissecting the weaknesses of modality preference theories. They clearly and carefully analyse the nature of the evidence for modality preference and conclude that there is little if any warrant for the use of modality preference, particularly because task appropriateness has a stronger influence. The author wonders, why have they had to write it? Why was--to pick one out of many--the thorough review by Pashler, McDaniel, Rohrer, and Bjork (2009) which formed a special issue of Psychological Science in the Public Interest not sufficient? What is it about learning styles that is so resistant to critique? In this commentary, the author will share some of the intellectual process background to a previous review (Coffield, Moseley, Hall, & Ecclestone, 2004a, 2004b; Hall & Moseley, 2005), consider how the work can be said to have impact in terms of academic conversations through published work, and finally, reflect on the many conversations the author has had with teachers in schools, colleges and universities. The author will conclude with her current working hypothesis about the attraction of learner-centred frameworks compared to the ongoing personal challenge of being an interesting and effective teacher. [For the article that the author is responding to, "Modality Preference and Learning Style Theories: Rethinking the Role of Sensory Modality in Learning," see EJ1186493.]

ImportanceMost research to understand postacute sequelae of SARS-CoV-2 infection (PASC), or long COVID, has focused on adults, with less known about this complex condition in children. Research is needed to characterize pediatric PASC to enable studies of underlying mechanisms that will guide future treatment.ObjectiveTo identify the most common prolonged symptoms experienced by children (aged 6 to 17 years) after SARS-CoV-2 infection, how these symptoms differ by age (school-age [6-11 years] vs adolescents [12-17 years]), how they cluster into distinct phenotypes, and what symptoms in combination could be used as an empirically derived index to assist researchers to study the likely presence of PASC.Design, setting, and participantsMulticenter longitudinal observational cohort study with participants recruited from more than 60 US health care and community settings between March 2022 and December 2023, including school-age children and adolescents with and without SARS-CoV-2 infection history.ExposureSARS-CoV-2 infection.Main outcomes and measuresPASC and 89 prolonged symptoms across 9 symptom domains.ResultsA total of 898 school-age children (751 with previous SARS-CoV-2 infection [referred to as infected] and 147 without [referred to as uninfected]; mean age, 8.6 years; 49% female; 11% were Black or African American, 34% were Hispanic, Latino, or Spanish, and 60% were White) and 4469 adolescents (3109 infected and 1360 uninfected; mean age, 14.8 years; 48% female; 13% were Black or African American, 21% were Hispanic, Latino, or Spanish, and 73% were White) were included. Median time between first infection and symptom survey was 506 days for school-age children and 556 days for adolescents. In models adjusted for sex and race and ethnicity, 14 symptoms in both school-age children and adolescents were more common in those with SARS-CoV-2 infection history compared with those without infection history, with 4 additional symptoms in school-age children only and 3 in adolescents only. These symptoms affected almost every organ system. Combinations of symptoms most associated with infection history were identified to form a PASC research index for each age group; these indices correlated with poorer overall health and quality of life. The index emphasizes neurocognitive, pain, and gastrointestinal symptoms in school-age children but change or loss in smell or taste, pain, and fatigue/malaise-related symptoms in adolescents. Clustering analyses identified 4 PASC symptom phenotypes in school-age children and 3 in adolescents.Conclusions and relevanceThis study developed research indices for characterizing PASC in children and adolescents. Symptom patterns were similar but distinguishable between the 2 groups, highlighting the importance of characterizing PASC separately for these age ranges.

Postsecondary chemistry instructors typically have received little pedagogical training as graduate students and postdoctoral research assistants. Moreover, professional development opportunities are often limited at their own institution. This lack of training has resulted in a gap between the instructional strategies enacted in chemistry courses and the results of discipline-based education research. Members of the Cottrell Scholars Collaborative initiated the New Faculty Workshop (CSC NFW) program in 2012 in order to address this gap. This annual, two-day workshop provides newly-hired chemistry assistant professors from research-intensive universities with training on evidence-based instructional practices. This article presents the results of a longitudinal, quasi-experimental design study that evaluates the short and long-term impacts of the workshop. Online surveys were collected immediately before and after the workshop, as well as one year later from CSC NFW participants and a control group that consisted of newly-hired chemistry faculty who did not participate in the workshop. Surveys measured faculty's awareness and use of evidence-based instructional practices, teaching self-efficacy, and beliefs about teaching. Classroom video recordings were also collected during the fall semester following the workshop and two years later. These data were triangulated with the Student Evaluation for Educational Quality (SEEQ) survey, which was collected from students in the observed classrooms. Findings indicate that, in the short-term, the CSC NFW was successful in raising workshop participants' self-efficacy, shifting their teaching beliefs toward student-centered teaching, and increasing their use of interactive teaching. Longitudinal data demonstrate that further pedagogical support is required in order for these impacts to be sustained.

The Cottrell Scholars Collaborative New Faculty Workshop (CSC NFW) is a professional development program that was initiated in 2012 to address absences in the preparation of chemistry faculty at research universities as funded researchers and educators (i.e., teacher-scholars). The primary focus of the workshop is an introduction to evidence-based teaching methods; other topics including mentoring, work-life balance, time management, and grant writing are also addressed. A longer-term aim of the workshop is to develop lifelong teacher-scholars by encouraging workshop participants to engage with teaching-focused faculty learning communities through the CSC NFW and at their institutions. The workshop also provides a platform to investigate the adoption of student-centered pedagogies among new faculty, and a study of that process was initiated concurrently. Thus, the aim of the workshop program is to address professional development needs as well as understand the efficacy of that effort.

In this paper, an application of open-ended textual feedback is presented as a tool to evaluate the perceptions and needs of teachers tasked with implementing computational thinking in the K-12 curriculum. Semantic analysis tools, including sentiment analysis and thematic analysis, facilitated the identification of common themes in openended textual feedback. Results show that semantic analysis techniques can be useful in evaluating formative assessment data or open-ended feedback to discover response patterns, which may aid in determining actionable insights related to adult learner perceptions, interests, and self-efficacy. Formative assessment data were collected from a unique professional development workshop to promote computational thinking and curriculum integration in core subjects, including writing, math, science, and social studies, with the goal of discovering the barriers that rural teachers face in developing and implementing lesson plans for grades 3-8 teachers in a rural midwestern state in the USA to promote computational thinking and curriculum integration in core subjects, including writing, math, science, and social studies, with the goal of discovering the barriers that rural teachers face in developing and implementing lesson plans.

Many machine learning techniques are used as drug discovery tools with the intent to speed characterization by determining relationships between compound structure and biological function. However, particularly in anticancer drug discovery, these models often make only binary decisions about the biological activity for a narrow scope of drug targets. We present a feed-forward neural network, PECAN (Prediction Engine for the Cytostatic Activity of Natural product-like compounds), that simultaneously classifies the potential antiproliferative activity of compounds against 59 cancer cell lines. It predicts the activity to be one of six categories, indicating not only if activity is present but the degree of activity. Using an independent subset of NCI data as a test set, we show that PECAN can reach 60.1% accuracy in a six-way classification and present further evidence that it classifies based on useful structural features of compounds using a within-one measure that reaches 93.0% accuracy.

This study assesses the impact of secondary orientations on the tensile deformation behavior of single-crystal superalloys at mid-temperature of 760 °C. Tensile tests and stress-strain analyses were performed on specimens with primary orientation [001] and secondary orientations [100], [410], and [110]. Stress distributions were modeled using Abaqus software, while fracture behavior, slip system activation, oxidation, lattice rotation, and micro-dislocation movements were investigated using optical microscopy (OM), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), electron backscatter diffraction (EBSD), and transmission electron microscopy (TEM). Findings reveal that the [100] orientation, due to the activation of coplanar dual slip systems, underwent significant strain hardening, exhibiting the highest strength and lowest ductility due to restricted lattice rotation. In contrast, the [410] and [110] orientations, each with a single primary slip system, showed reduced strength. The [410] orientation demonstrated enhanced ductility due to extensive lattice rotation, whereas the [110] orientation displayed the lowest strength, primarily due to premature cracking aligned with slip lines on the surface oxide film. Dominant deformation microstructures involved isolated stacking faults (SFs) shearing into γ′ precipitates, with the formation of immobile dual Lomer-Cottrell (L-C) locks at intersecting slip planes significantly contributing to microstructural strengthening.

The PI3K enzymes modify phospholipids to regulate cell growth and differentiation. Somatic variants in PI3K are recurrent in cancer and drive a proliferative phenotype. Somatic mosaicism of PIK3R1 and PIK3CA are associated with vascular anomalies and overgrowth syndromes. Germline PIK3R1 variants are associated with varying phenotypes, including immunodeficiency or facial dysmorphism with growth delay, lipoatrophy, and insulin resistance associated with SHORT syndrome. There has been limited study of the molecular mechanism to unify our understanding of how variants in PIK3R1 drive both undergrowth and overgrowth phenotypes. Thus, we compiled genomic variants from cancer and rare vascular anomalies and sought to interpret their effects using an unbiased physics-based simulation approach for the protein complex. We applied molecular dynamics simulations to mechanistically understand how genetic variants affect PIK3R1 and its interactions with PIK3CA. Notably, iSH2 genetic variants associated with undergrowth destabilize molecular interactions with the PIK3CA receptor binding domain in simulations, which is expected to decrease activity. On the other hand, overgrowth and cancer variants lead to loss of inhibitory interactions in simulations, which is expected to increase activity. We find that all disease variants display dysfunctions on either structural characteristics or intermolecular interaction energy. Thus, this comprehensive characterization of novel mosaic somatic variants associated with two opposing phenotypes has mechanistic importance and biomedical relevance and may aid in future therapeutic developments.

IMPORTANCE: The prevalence, pathophysiology, and long-term outcomes of COVID-19 (post-acute sequelae of SARS-CoV-2 [PASC] or Long COVID) in children and young adults remain unknown. Studies must address the urgent need to define PASC, its mechanisms, and potential treatment targets in children and young adults. OBSERVATIONS: We describe the protocol for the Pediatric Observational Cohort Study of the NIHs REsearching COVID to Enhance Recovery (RECOVER) Initiative. RECOVER-Pediatrics is an observational meta-cohort study of caregiver-child pairs (birth through 17 years) and young adults (18 through 25 years), recruited from more than 100 sites across the US. This report focuses on two of four cohorts that comprise RECOVER-Pediatrics: 1) a de novo RECOVER prospective cohort of children and young adults with and without previous or current infection; and 2) an extant cohort derived from the Adolescent Brain Cognitive Development (ABCD) study (n = 10,000). The de novo cohort incorporates three tiers of data collection: 1) remote baseline assessments (Tier 1, n = 6000); 2) longitudinal follow-up for up to 4 years (Tier 2, n = 6000); and 3) a subset of participants, primarily the most severely affected by PASC, who will undergo deep phenotyping to explore PASC pathophysiology (Tier 3, n = 600). Youth enrolled in the ABCD study participate in Tier 1. The pediatric protocol was developed as a collaborative partnership of investigators, patients, researchers, clinicians, community partners, and federal partners, intentionally promoting inclusivity and diversity. The protocol is adaptive to facilitate responses to emerging science. CONCLUSIONS AND RELEVANCE: RECOVER-Pediatrics seeks to characterize the clinical course, underlying mechanisms, and long-term effects of PASC from birth through 25 years old. RECOVER-Pediatrics is designed to elucidate the epidemiology, four-year clinical course, and sociodemographic correlates of pediatric PASC. The data and biosamples will allow examination of mechanistic hypotheses and biomarkers, thus providing insights into potential therapeutic interventions. CLINICAL TRIALS.GOV IDENTIFIER: Clinical Trial Registration: http://www.clinicaltrials.gov. Unique identifier: NCT05172011.

Abstract PIK3CA-related overgrowth spectrum (PROS) disorders are caused by somatic mosaic variants that result in constitutive activation of the phosphatidylinositol-3-kinase/AKT/mTOR pathway. Promising responses to molecularly targeted therapy have been reported, although identification of an appropriate agent can be hampered by the mosaic nature and corresponding low variant allele frequency of the causal variant. Moreover, our understanding of the molecular consequences of these variants—for example how they affect gene expression profiles—remains limited. Here we describe in vitro expansion of a human capillary malformation followed by molecular characterization using exome sequencing, single cell gene expression, and targeted long-read single cell RNA-sequencing in a patient with clinical features consistent with Megalencephaly-Capillary Malformation Syndrome (MCAP, a PROS condition). These approaches identified a targetable PIK3CA variant with expression restricted to PAX3+ fibroblast and undifferentiated keratinocyte populations. This study highlights the innovative combination of next-generation single cell sequencing methods to better understand unique transcriptomic profiles and cell types associated with MCAP, revealing molecular intricacies of this genetic syndrome.

Abstract Recognition of viral infection often relies on the detection of double-stranded RNA (dsRNA), a process that is conserved in many different organisms. In mammals, proteins such as MDA5, RIG-I, OAS, and PKR detect viral dsRNA, but struggle to differentiate between viral and endogenous dsRNA. This study investigates an shRNA targeting DDX54’s potential to activate PKR, a key player in the immune response to dsRNA. Knockdown of DDX54 by a specific shRNA induced robust PKR activation in human cells, even when DDX54 is overexpressed, suggesting an off-target mechanism. Activation of PKR by the shRNA was enhanced by knockdown of ADAR1, a dsRNA binding protein that suppresses PKR activation, indicating a dsRNA-mediated mechanism. In vitro assays confirmed direct PKR activation by the shRNA. These findings emphasize the need for rigorous controls and alternative methods to validate gene function and minimize unintended immune pathway activation.

Seminal fluid extracellular vesicles (SFEVs) have previously been shown to interact with spermatozoa and influence their fertilisation capacity. Here, we sought to extend these studies by exploring the functional consequences of SFEV interactions with human spermatozoa. SFEVs were isolated from the seminal fluid of normozoospermic donors prior to assessing the kinetics of sperm-SFEV binding in vitro, as well as the effects of these interactions on sperm capacitation, acrosomal exocytosis, and motility profile. Biotin-labelled SFEV proteins were transferred primarily to the flagellum of spermatozoa within minutes of co-incubation, although additional foci of SFEV biotinylated proteins also labelled the mid-piece and head domain. Functional analyses of high-quality spermatozoa collected following liquefaction revealed that SFEVs did not influence sperm motility during incubation at pH 5, yet SFEVs induced subtle increases in total and progressive motility in sperm incubated with SFEVs at pH 7. Additional investigation of sperm motility kinematic parameters revealed that SFEVs significantly decreased beat cross frequency and increased distance straight line, linearity, straightness, straight line velocity, and wobble. SFEVs did not influence sperm capacitation status or the ability of sperm to undergo acrosomal exocytosis. Functional assessment of both high- and low-quality spermatozoa collected prior to liquefaction showed limited SFEV influence, with these vesicles inducing only subtle decreases in beat cross frequency in spermatozoa of both groups. These findings raise the prospect that, aside from subtle effects on sperm motility, the encapsulated SFEV cargo may be destined for physiological targets other than the male germline, notably the female reproductive tract. Lay Summary A male’s influence over the biological processes of pregnancy extends beyond the provision of sperm. Molecular signals present in the ejaculate can influence the likelihood of pregnancy and healthy pregnancy progression, but the identity and function of these signals remain unclear. In this study, we wanted to understand if nano-sized particles present in the male ejaculate, called seminal fluid extracellular vesicles, can assist sperm in traversing the female reproductive tract to access the egg. To explore this, we isolated seminal fluid extracellular vesicles from human semen and incubated them with sperm. Our data showed that seminal fluid extracellular vesicles act to transfer molecular information to sperm, but this resulted in only subtle changes to the movement of sperm.

Abstract Single crystal paleointensity (SCP) reveals that the Moon lacked a long-lived core dynamo, though mysteries remain. An episodic dynamo, seemingly recorded by some Apollo basalts, is temporally and energetically problematic. We evaluate this enigma through study of ~3.7 billion-year-old (Ga) Apollo basalts 70035 and 75035. Whole rock analyses show unrealistically high nominal magnetizations, whereas SCP indicate null fields, illustrating that the former do not record an episodic dynamo. However, deep crustal magnetic anomalies might record an early lunar dynamo. SCP studies of 3.97 Ga Apollo breccia 61016 and 4.36 Ga ferroan anorthosite 60025 also yield null values, constraining any core dynamo to the Moon’s first 140 million years. These findings suggest that traces of Earth’s Hadean atmosphere, transferred to the Moon lacking a magnetosphere, could be trapped in the buried lunar regolith, presenting an exceptional target for future exploration.

In England and Wales, diocesan inspectors are charged with assessing the overall quality of Catholic education provided by Catholic schools. As part of this assessment, inspectors are required to give an account of the liturgical life of the school. Often the reports which result from these inspections refer to the degree of students' "active participation" in liturgy. This terminology has its roots in Biblical and patristic theological literature. Its meaning has evolved over time and has been used to describe a wide range of seemingly diffuse human behaviours. This article casts light on the meaning of "active participation" in the context of Diocesan inspectors and offers some reflections on how this term could be refined in order to make diocesan inspections more informative.

A brief introduction to the use of digital simulations in electrochemistry is given by a detailed description of the simulation of Cottrell’s experiment in the LabVIEW programming language. A step-by-step approach is followed and different simulation techniques (explicit and implicit Euler, Runge–Kutta and Crank–Nicolson methods) are applied. The applied techniques are introduced and discussed on the basis of Padé approximants. The paper might be found useful by undergraduate and graduate students familiarizing themselves with the digital simulation of electrochemical problems, as well as by university lecturers involved with the teaching of theoretical electrochemistry.