A lower bound on the number of cosmic ray events required to measure source catalogue correlations

Recent analyses of cosmic ray arrival directions have resulted in evidence for a positive correlation with active galactic nuclei positions that has weak significance against an isotropic source distribution. In this paper, we explore the sample size needed to measure a highly statistically significant correlation to a parent source catalogue. We compare several scenarios for the directional scattering of ultra-high energy cosmic rays given our current knowledge of the galactic and intergalactic magnetic fields. We find significant correlations are possible for a sample of $>$1000 cosmic ray protons with energies above 60 EeV.Comment: 23 pages, 9 figure

Ontogeny of postcranial morphology and locomotor behavior in Propithecus verreauxi coquereli and Lemur catta

Despite living under the same environmental pressures and sympatrically in many cases, Propithecus verreauxi and Lemur catta have evolved very different strategies for survival in stochastic environmental conditions. P. verreauxi show slow somatic growth, low maternal investment, and rapid dental growth while L. catta show faster somatic growth, high maternal investment, and slower dental growth. P. v. coquereli are highly specialized for vertical clinging and leaping (VCL) among lemurs, while L. catta, the most terrestrial of lemurs, use a wider variety of locomotor types including quadrupedalism, climbing, and leaping. P. v. coquereli have unusually long legs and muscular thighs while L. catta have more similar limb lengths and muscular proximal limb segments (Lessertisseur and Jouffroy, 1973; Jouffroy, 1975). Little is known of the ontogenetic trajectories by which these adult forms are acquired. Because selection acts on the entire life cycle of an animal, it is important to investigate the morphological and locomotor changes occurring early in development. These changes might be important components to each species’ survival strategy that allow infant primates to travel with a group of larger adults and survive to adulthood. I examined changes in locomotor behavior and limb morphology from 0-2 years in L. catta and P. v. coquereli. Limb segment lengths, limb segment circumferences, and body mass were recorded every 2 weeks in infants and every 4 weeks in yearlings at the Duke Lemur Center (DLC). Locomotor data were collected on infants transitioning to locomotor independence and yearlings of each species in free-ranging enclosures at the DLC using locomotor bout sampling. Results indicate that both species are born with upper limb lengths similar to lower limb lengths, whereas only P. v. coquereli dissociates upper- and lower limb growth to reach adult limb proportions. P. v. coquereli transitional infants and yearlings use similar overall locomotor behavior and undergo rapid postcranial growth to achieve the limb proportions necessary for VCL by the time of locomotor independence. Relative to upper limb length, lower limb length is even longer in juveniles first leaping independently than in yearlings and adults. Relatively long hindlimbs may allow juveniles to achieve leaping take-off velocity similar to adults despite absolutely smaller size. L. catta transitional infants exhibit a different distribution of locomotor behavior than yearlings despite similarities in limb proportions. Much like P. v. coquereli juveniles are “ecological adults” in terms of their rapid dental development, they seem to also be “ecological adults” in terms of locomotor behavior. Because of the demand for using VCL at a young age, and despite overall slow postcranial growth, P. v. coquereli transitional infants are on a rapid growth trajectory towards achieving the limb proportions necessary for specialized leaping. Lowest IMI values at locomotor independence, increased leap frequency paired with decreased leap distance, and high positive allometric growth of the tail are three key findings that provide evidence as to how P. v. coquereli transitional infants are able to display similar locomotor repertoires as yearlings in order to keep up with the group to survive, despite being absolutely smaller

Narratives of Anatomy: Arranging Identity and Regulating Visibility in the Nineteenth Century Anatomical Museum

During the nineteenth century, museums dedicated to the collection, preservation, and display of human anatomy became familiar institutions in America and Europe. The anatomical museum operated under one of two guises: popular museums run as commercial establishments, or medical museums attached to a professional medical society or college. Over the course of the century, the medical establishment sought to cement its authority over anatomy by legitimating its expertise through specialized training. Doctors criticized commercial anatomical museums, which were eventually closed under accusations of obscenity, yet there was considerable overlap in the types of objects on display at both museums. This paper examines how the medical museum was permitted to supersede its commercial cousin and explores the exhibitionary narratives at the sites of both types of institutions

AN EXAMINATION OF FACTORS THAT INFLUENCE FRIENDSHIPS IN YOUNG ADULTS FROM INTACT AND DIVORCED FAMILIES

Specific factors affecting young adult friendship development have been identified by the literature with little focus on which are most influential in determining friendship composition.. Hierarchical regression was used to examine such factors. Participants included 400 undergraduate Psychology students at a state university in the mid-Atlantic region. Findings indicated parental relationships were the strongest predictor of friendship quality. Parent-child bonds, conflict between parents, and emotion regulation skills best predicted levels of intimacy. Parent-child bond-especially with mother-best predicted satisfaction with friendship network as did conflict between parents. In addition, parent-child bond with mother and conflict between parents were found more important than emotion regulation skills although such skills were still found significant. Contrary to predictions life events were not significant to all outcome variables. Instead life events were found significant only to satisfaction with friendship networks. Finally, parental marital status was found significant, but minimally, only for friendship intimacy

Psycholinguistic changes in the communication of adolescent users in a suicidal ideation online community during the COVID-19 pandemic

Since the outbreak of the COVID-19 pandemic, increases in suicidal ideation and suicide attempts in adolescents have been registered. Many adolescents experiencing suicidal ideation turn to online communities for social support. In this retrospective observational study, we investigated the communication—language style, contents and user activity—in 7975 unique posts and 51,119 comments by N = 2862 active adolescent users in a large suicidal ideation support community (SISC) on the social media website reddit.com in the onset period of the COVID-19 pandemic. We found significant relative changes in language style markers for hopelessness such as negative emotion words (+ 10.00%) and positive emotion words (− 3.45%) as well as for social disengagement such as social references (− 8.63%) and 2nd person pronouns (− 33.97%) since the outbreak of the pandemic. Using topic modeling with Latent Dirichlet Allocation (LDA), we identified significant changes in content for the topics Hopelessness (+ 23.98%), Suicide Methods (+ 17.11%), Social Support (− 14.91%), and Reaching Out to users (− 28.97%). Changes in user activity point to an increased expression of mental health issues and decreased engagement with other users. The results indicate a potential shift in communication patterns with more adolescent users expressing their suicidal ideation rather than relating with or supporting other users during the COVID-19 pandemic

Releasing the Brake: Targeting Cbl-b to Enhance Lymphocyte Effector Functions

The E3 ubiquitin ligase Cbl-b is an established nonredundant negative regulator of T-cell activation. Cbl-b fine-tunes the activation threshold of T cells and uncouples T cells from their vital need of a costimulatory signal to mount a productive immune response. Accordingly, mice deficient in cblb are prone to autoimmunity and reject tumors. The latter has been described to be mediated via CD8+ T cells, which are hyperactive and more abundant in shrinking tumors of cblb-deficient animals. This might at least also in part be mediated by resistance of cblb-deficient T cells to negative cues exerted by tumor-associated immuno-suppressive factors, such as TGF-β and regulatory T cells (Treg). Experiments using cblb-deficient T cells either alone or in combination with vaccines validate the therapeutic concept of enhancing the efficacy of adoptively transferred lymphocytes to treat malignant tumors. This paper summarizes the current knowledge about the negative regulatory role of Cbl-b in T-cell activation and its potential therapeutic implications for cancer immunotherapy

Mobile Devices for Early Literacy Intervention and Research with Global Reach

Extensive work focuses on the uses of technology at scale for post-literate populations (e.g., MOOC, Learning Games, LMS’s). Little attention is afforded to non-literate populations, particularly in the developing world. This paper presents an approach using mobile devices with the ultimate goal to reach 770 million people. We developed a novel platform with a cloud backend to deliver educational content to over a thousand marginalized children in different countries:specifically, in remote villages without schools, urban slums with overcrowded schools, and at-risk, rural schools. Here we describe the theoretical basis of our system and results from case studies in three educational contexts. This model will help researchers and designers understand how mobile devices can help children acquire basic skills and aid each other’s learning when the benefit of teachers is limited or non-existent.Italian Development CouncilMRP FoundationRoanoke County School

CHILDREN WHO HAVE EXPERIENCED TRAUMA: AN EXAMINATION OF THE ROLE OF RACE, ETHNICITY, AND CULTURAL FACTORS IN PRESENTING SYMPTOMS AND AT THREE MONTH (OR FIRST RECORDED) FOLLOW UP

Child traumatic stress is a pervasive problem that affects the well-being and healthy development of children from all races, ethnicities, and cultures. Major factors known to affect trauma symptoms include type of trauma, level or severity of trauma exposure, and age and gender of children. Utilizing Bronfenbrenner’s ecological model, this study measured the additional influence of children’s race, ethnicity, and cultural factors on symptoms after trauma. A dataset of children in treatment after experiencing trauma (0-21 years, N = 10,115) from The National Child Traumatic Stress Network (NCTSN), a federally funded initiative that collected longitudinal data across 56 research and treatment centers in the US, was examined, looking at clinical symptoms at baseline and at three month (or first recorded) follow-up. Predictors for symptoms included number of trauma types, age, gender, race, ethnicity (Latino/non-Latino), and three cultural markers, born outside the United States, English as the primary language not spoken at home, and refugee/immigrant status. Results (hierarchical regressions, logistic regressions) confirmed that age, gender, and number of trauma types predict the scores and clinical level of eight validated outcomes (e.g., CBCL externalizing, internalizing; PTSD measures) as well as the total numbers of functional problems and clinical problems. Results also demonstrated that race, ethnicity, and culture affect symptoms but to a very small extent (i.e., these accounted for little variance) and in varying directions. For example, Black/African American children had lower internalizing scores compared to White/Caucasian children, while being Latino was associated with lower externalizing and higher internalizing scores than non-Latinos. Children with differing cultures sometimes scored better, sometimes worse, than their counterparts. For example, children who spoke English at home and were born in the United States had more functional problems, though fewer clinical problems. At three month (or first recorded) follow up, results demonstrated all children’s scores improving. No differences at three month (or first recorded follow up) were found between our predictors in clinical rates except for children with more types of trauma who continued to show a greater likelihood of falling into the clinical range for externalizing and internalizing. Discussion focuses on the possible protective effects of cultural factors and the importance of an ecological model in understanding trauma symptoms in diverse populations

Digital Casebooks: Case-Based Self-Learning Environments

Die steigende Heterogenität der Studierenden geht mit unterschiedlichen Anforderungen an Lehr-Lern-Materialien einher. Aber auch die in unterschiedlichen Transformations­prozessen eingebundene Lebenswelt und die damit verbundenen neuen Themenfelder erfordern eine erhöhte Adaptivität universitärer Curricula. Der vorliegende Beitrag stellt das Projekt «Digital Casebooks» vor und geht der Frage nach, wie die Konzeption und digitale Umsetzung fallzentrierter Selbstlernangebote zur individualisierten Verknüpfung von Theorie und Praxis im Lehramtsstudium erfolgen können. Neben konzeptionellen Überlegungen wird auch die hochschuldidaktische Herausforderung der barrierefreien Gestaltung von Lehr-Lern-Angeboten als ein Aspekt des proaktiven Umgangs mit der Heterogenität der Studierenden beleuchtet.The increasing heterogeneity of students is intertwined with different challenges for teaching and learning. Among other things, there is a need for more adaptivity of university curricula. This article provides an insight into the project “Digital Casebooks”. Presented are the conception and digital implementation of case-based self-learning environments with the aim of linking theory and practice in teacher education. In addition to conceptual considerations, the challenge of barrier-free learning in online learning environments is highlighted

Effects of muscle fatigue on gait characteristics under single and dual-task conditions in young and older adults

Muscle fatigue and dual-task walking (e.g., concurrent performance of a cognitive interference (CI) while walking) represent major fall risk factors in young and older adults. Thus, the objectives of this study were to examine the effects of muscle fatigue on gait characteristics under single and dual-task conditions in young and older adults and to determine the impact of muscle fatigue on dual-task costs while walking