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Epigenetic mechanisms regulate the multilineage differentiation capacity of hematopoietic stem cells (HSCs) into a variety of blood and immune cells. Mapping the chromatin dynamics of functionally defined cell populations will shed mechanistic insight into 2 major, unanswered questions in stem cell biology: how does epigenetic identity contribute to a cell type's lineage potential, and how do cascades of chromatin remodeling dictate ensuing fate decisions? Our recent work revealed evidence of multilineage gene priming in HSCs, where open cis-regulatory elements (CREs) exclusively shared between HSCs and unipotent lineage cells were enriched for DNA binding motifs of known lineage-specific transcription factors. Oligopotent progenitor populations operating between the HSCs and unipotent cells play essential roles in effecting hematopoietic homeostasis. To test the hypothesis that selective HSC-primed lineage-specific CREs remain accessible throughout differentiation, we used ATAC-seq to map the temporal dynamics of chromatin remodeling during progenitor differentiation. We observed epigenetic-driven clustering of oligopotent and unipotent progenitors into distinct erythromyeloid and lymphoid branches, with multipotent HSCs and MPPs associating with the erythromyeloid lineage. We mapped the dynamics of lineage-primed CREs throughout hematopoiesis and identified both unique and shared CREs as potential lineage reinforcement mechanisms at fate branch points. Additionally, quantification of genome-wide peak count and size revealed overall greater chromatin accessibility in HSCs, allowing us to identify HSC-unique peaks as putative regulators of self-renewal and multilineage potential. Finally, CRISPRi-mediated targeting of ATACseq-identified putative CREs in HSCs allowed us to demonstrate the functional role of selective CREs in lineage-specific gene expression. These findings provide insight into the regulation of stem cell multipotency and lineage commitment throughout hematopoiesis and serve as a resource to test functional drivers of hematopoietic lineage fate.

Based on the vast challenges college students experience, and the current mental health crisis on college campuses, the current study investigated how student-support providers assist and encourage students to enact resilience. We analyzed data from interviews with 25 campus student-support leaders in regard to how they support resilience in college students. Consistent with the communication theory of resilience (Buzzanell, P. M. (2010). Resilience: Talking, resisting, and imagining new normalcies into being. "Journal of Communication," 60(1), 1-14. https://doi.org/10.1111/j.1460-2466.2009.01469.x), participants discussed interactions and programming that aligned with all five communicative processes (crafting normalcy, affirming identity anchors, maintaining and using social networks, finding alternative logics, legitimizing negative feelings while foregrounding productive action). Further analysis led to four themes, which helped us develop a framework for supporting student resilience that included mattering and belonging, mentorship, reframing and reorientation, and reflection and finding strengths. Using this framework, we discuss theoretical and practical ideas for supporting students through the challenges associated with the college environment.

Guided reading questions (GRQs) are a formative assessment activity to facilitate student learning. We conducted four experiments to test if GRQs improved student performance on evaluative assessments. Experiment 1 compared test scores between classes that received GRQs or not. Experiment 2 modeled the impact of multiple formative assessments, including GRQs, on evaluative assessments. Experiment 3 examined how optional GRQs impacted quiz scores. Experiment 4 compared test performance between mandatory or optional GRQs. The overall results found weak evidence for the benefits of GRQs, but significant associations between GRQ and evaluative assessment scores. GRQ scores may better indicate a student's academic habits than provide a unique intervention. Graded GRQs may provide external motivation for textbook reading and access to weekly continuous assessment activity provides benefits for most students.

The Karlsruhe Tritium Neutrino (KATRIN) experiment aims at measuring the effective electron neutrino mass with a sensitivity of 0.2 eV/c2, i.e., improving on previous measurements by an order of magnitude. Neutrino mass data taking with KATRIN commenced in early 2019, and after only a few weeks of data recording, analysis of these data showed the success of KATRIN, improving on the known neutrino mass limit by a factor of about two. This success very much could be ascribed to the fact that most of the system components met, or even surpassed, the required specifications during long-term operation. Here, we report on the performance of the laser Raman (LARA) monitoring system which provides continuous high-precision information on the gas composition injected into the experiment's windowless gaseous tritium source (WGTS), specifically on its isotopic purity of tritium-one of the key parameters required in the derivation of the electron neutrino mass. The concentrations cx for all six hydrogen isotopologues were monitored simultaneously, with a measurement precision for individual components of the order 10-3 or better throughout the complete KATRIN data taking campaigns to date. From these, the tritium purity, εT, is derived with precision of

The determination of the neutrino mass is one of the major challenges in astroparticle physics today. Direct neutrino mass experiments, based solely on the kinematics of β -decay, provide a largely model-independent probe to the neutrino mass scale. The Karlsruhe Tritium Neutrino (KATRIN) experiment is designed to directly measure the effective electron antineutrino mass with a sensitivity of 0.2eV (90 % CL). In this work we report on the first operation of KATRIN with tritium which took place in 2018. During this commissioning phase of the tritium circulation system, excellent agreement of the theoretical prediction with the recorded spectra was found and stable conditions over a time period of 13 days could be established. These results are an essential prerequisite for the subsequent neutrino mass measurements with KATRIN in 2019.

Participation in youth sport is positively associated with physical fitness and performance. The purpose of the current study was to examine if physical fitness measures during childhood and early adolescence predicted high school sport participation. Participants included youth in the Michigan State University Motor Performance Study. Measures consisted of the endurance shuttle run, Wells sit-and-reach, jump and reach, standing long jump, agility shuttle run and 30-yard dash. Individual, generalized estimating equation models were used to estimate the association between each measure and the odds of participating in high school sport. For both sexes, the endurance shuttle run and agility shuttle run were related to sport participation. For boys only, the long jump and 30-yard dash were also associated with sport participation. Better physical fitness and performance across several dimensions in childhood, including those related to motor skills, enhanced the likelihood of sport participation in high school.

The Michigan State University Motor Performance Study (MPS) was initiated in 1967 and lasted 32 years. Three central components existed: 1) Educational component, in which students experienced applied work with youth; 2) Instructional component, whereby enrolled youth received sport-specific skill instruction; and 3) Research component. The primary goals of the research component of the MPS were to examine: 1) the changes over time that occur in the physical growth, biological maturity, and motor skill acquisition of children and youth; 2) the processes involved in the attainment of basic and complex motor skills; and 3) the influence of changes in the learners' environment on their rates of motor skill acquisition. Several growth and maturation, motor competence, and physical performance/fitness variables were collected, and a follow-up study examined participants' adult physical activity, sport participation, and health outcomes. This manuscript describes methods used in the research component of the MPS and the follow-up.

Research tracking sport participation from youth to adulthood is relatively rare, as is research that tracks youth sport participation with regard to adult physical activity (PA) levels, especially in the United States. Aims of this study were: 1) To investigate the degree to which sport participation tracked across youth, adolescence, and early adulthood in a sample of participants from the Michigan State University Motor Performance Study (MPS), and 2) Determine if differences existed in their levels of adult PA relative to prior sport participation. In total, 256 (60.8%) former participants from the MPS completed follow-up surveys regarding routine sport participation and PA across the previous year. Sport participation tracked consistently from youth to college. Further, regardless of the level of youth sport participation, adult leisure time PA was relatively consistent among groups. Although the study did not directly test the influence of the MPS on subsequent adult outcomes, our findings suggest that participants' past sport participation was not a good predictor of adult PA for those who were involved in a program that emphasized fundamental motor skills in youth. Further investigation of such programs can help to better inform their influence on adult PA.

Internships are considered high-impact practices in higher education. However, to date, such programs to prepare kinesiology students for careers as strength and conditioning (S&C) coaches have rarely been studied for impact. The purpose of this study was to qualitatively assess interns' perceived benefits of interning as S&C coaches. Five interns completed an average of 36 hours of coaching over a 12-week S&C program for a university rugby team. Interns rated themselves on key areas and wrote a self-reflection on how the internship contributed to their professional development. Key themes to emerge were skill development, especially in the areas of monitoring and providing feedback to athletes; learning how to work as a team of coaches; and being more aware and critical of their own knowledge skills and abilities and how much more professional development they will need throughout their career.

Hematopoiesis is arguably one of the best understood stem cell systems; however, significant challenges remain to reach a consensus understanding of the lineage potential, heterogeneity, and relationships of hematopoietic stem and progenitor cell populations. To gain new insights, we performed quantitative analyses of mature cell production from hematopoietic stem cells (HSCs) and multiple hematopoietic progenitor populations. Assessment of the absolute numbers of mature cell types produced by each progenitor cell revealed a striking erythroid dominance of all myeloid-competent progenitors assessed, accompanied by strong platelet reconstitution. All populations with myeloid potential also produced robust numbers of red blood cells and platelets in vivo. Clonal analysis by single-cell transplantation and by spleen colony assays revealed that a significant fraction of HSCs and multipotent progenitors have multilineage potential at the single-cell level. These new insights prompt an erythroid-focused model of hematopoietic differentiation.