Provable Run Time Safety Assurance for a Non-Linear System

Systems that are modeled by non-linear continuous-time differential equations with uncertain parameters have proven to be exceptionally difficult to formally verify. The past few decades have produced a number of useful verification tools which can be applied to such systems but each is applicable to only a subset of possible verification scenarios. The Level Sets Toolbox (LST) is one such tool which is directly applicable to non-linear systems, however, it is limited to systems of relatively small continuous state space dimension. Other tools such as PHAVer and the SpaceEx invariant of the Le Guernic-Girard (LGG) support function algorithm are specifically designed for hybrid systems with linear dynamics and linear constraints but can accommodate hundreds of continuous states. The application of these linear reachability tools to non-linear models has been achieved by approximating non-linear systems as linear hybrid automata (LHA). Unfortunately, the practical applicability and limitations of this approach are not yet well documented. The purpose of this thesis is to evaluate the performance and dimensionality limitations of PHAVer and the LGG support function algorithm when applied to a LHA approximation of a particular non-linear system. A collision avoidance scenario with autonomous differential drive robots is used as a case study to demonstrate that an over-approximated reachable set boundary can be generated and implemented as a run time safety assurance mechanism

DIRECTIONAL COMPRESSION AND MUSCLE ACTIVITY IN A RETIRED WORLD CUP ALPINE SKIER

The purpose of this study was to identify the effects of directional compression tights on muscle fatigue in alpine skiing as characterized by EMG. A retired world cup skier skied two different full days, one with directional compression tights and one without. In the morning and afternoon a single run of controlled turns was made while EMG, plantar pressure, and accelerometer data were collected. Plantar pressure data was used to divide EMG results into individual turns. Mean amplitude for vastus lateralis, adductor longus, rectus femoris, gluteus medius, and gluteus maximus was assessed by mean RMS amplitude of EMG. For a significance level of 0.01, no significant difference in turn times was determined. No significant differences were seen between morning and afternoon runs. A decreased mean RMS for the compression conditions was observed for rectus femoris (p \u3c 0.001) and vastus lateralis (p = 0.005)

Beyond the Volcanoes: A Community Partnership for Health in Rural Nicaragua

Background: Health inequities related to gender, ethnicity, socioeconomic status, and geography exist in rural Nicaragua. The purpose of this ongoing project is to improve health equity in rural Nicaragua through social transformation using community-based participatory action research. Bronfenbrenner\u27s ecological model of human development, school health, and primary health care theories provided the framework for this research. Methods: Community-based participatory action research involves six phases: partnership, assessment, planning, implementation, evaluation, and dissemination. In the evaluation phase, the goal was to use the data obtained during the assessment, planning, and implementation phases to evaluate the cookstove intervention in its ability to reach the community\u27s health-related goals. Pre- and post-test surveys were used to assess indoor air pollution including: kitchen layout, stove type, fuel usage, and women and children\u27s health. Results: Forty-eight community members participated in the cookstove evaluation. Pre-test surveys indicated that the community members used open fire stoves in closed kitchen spaces with wood being the primary fuel source. Women reported suffering from headaches, eye irritation, and chronic coughing. One year following the implementation phase, post-test surveys indicated a sustainable, significant improvement in women\u27s health (p=.05) but no significant change in the amount of wood used for cooking. Conclusion: Results from the cookstove evaluation were used by community members to guide the re-engineering of the cookstoves\u27 firebox to decrease wood consumption and improve deforestation. Partnership in community health research provides a mechanism to engage community members in social justice through working toward a common goal – sustainable health for all

Investigating ion recombination effects in a liquid‐filled ionization chamber array used for IMRT QA measurements

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134893/1/mp6822.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134893/2/mp6822_am.pd

Injury, Training, Biomechanical, and Physiological Profiles of Professional Breakdancers

# Background Breakdancing or breaking will enter the Olympics in 2024, however, there is a paucity of literature exploring the epidemiology, demands, and performance. # Purpose The purpose of this study was to describe injury and training profiles, along with the results of a short performance test battery, in a group of elite breakers. # Study Design Cross-sectional study (retrospective). # Methods Fourteen breakdancers (breakers) (4 Bgirls, 10 Bboys) participated in an interview regarding their injury and training history, endurance test (cycle VO~2max~ testing), counter movement jump, squat jump, drop jump, isometric hip abduction, adduction, shoulder external and internal rotation strength testing on a fixed-frame dynamometer. Breakers were divided into elite (n=10) and developing (n=4) based on their qualification for a world finals competition; Wilcoxen rank sums were used to compare the two groups, or in the case of strength testing between those with and without an injury history. # Results The breakers had a median 11.0 $$10.0 - 14.0$$ years breaking experience and trained 24.4 $$20.5 - 30.0$$ hours per week. The knee was the most commonly injured body part and most frequently injured joint, with the thigh being the most common site for muscle injuries. There were no differences in endurance testing or jump height testing results between elite and developing breakers. There was no difference in shoulder external or internal rotation strength between athletes with a history of shoulder injury and those without. Similarly, there was no difference in hip abduction or adduction strength in those with a history of hip injury and those without. # Conclusion The results of this study should be viewed with caution due to the small sample size. However, this study is the first to publish functional and physiological descriptives on breakers. The authors hope these results support clinicians treating breakers as well as encourages future research related to breaking. # Level of Evidence 2

Multiple and Consecutive Genome Editing Using i-GONAD and Breeding Enrichment Facilitates the Production of Genetically Modified Mice

Genetically modified (GM) mice are essential tools in biomedical research. Traditional methods for generating GM mice are expensive and require specialized personnel and equipment. The use of clustered regularly interspaced short palindromic repeats (CRISPR) coupled with improved-Genome editing via Oviductal Nucleic Acids Delivery (i-GONAD) has highly increased the feasibility of producing GM mice in research laboratories. However, genetic modification in inbred mouse strains of interest such as C57BL/6 (B6) is still challenging because of their low fertility and embryo fragility. We have successfully generated multiple novel GM mouse strains in the B6 background while attempting to optimize i-GONAD. We found that i-GONAD reduced the litter size in superovulated pregnant females but did not impact pregnancy rates. Natural mating or low-hormone dose did not increase the low fertility rate observed in superovulated B6 females. However, diet enrichment had a positive effect on pregnancy success. We also optimized breeding conditions to increase the survival of small litters by co-housing i-GONAD-treated pregnant B6 females with synchronized pregnant FVB/NJ companion mothers. Thus, GM mice generation was increased by an enriched diet and shared pup rearing with highly fertile females such as FVB/NJ. In the present study, we generated 16 GM mice using a CRISPR/Cas system to target individual and multiple loci simultaneously or consecutively. We also compared homology-directed repair efficiency using different methods for LoxP insertion for conditional knockout mouse production. We found that a two-step serial LoxP insertion, in which each LoxP sequence was inserted individually in different i-GONAD procedures, was a low-risk high-efficiency method for generating floxed mice

Trends in Gender Authorship and Collaborations: A 30-Year Comparative Bibliometric Analysis of Manuscripts from The Journal of Bone and Joint Surgery and The Bone and Joint Journal

Publishing original peer-reviewed research is essential for advancement through all career stages. Fewer women than men hold senior-level positions in academic medicine and, therefore, examining publication trends relative to gender is important. The goal of this study was to examine and compare publication trends in The Journal of Bone and Joint Surgery (JBJS) and The Bone and Joint Journal (BJJ) with a particular emphasis on trends regarding author gender. Data was collected and analyzed for manuscripts published in JBJS and BJJ over the past 30 years. For manuscripts published in 1986, 1996, 2006, and 2016, we recorded the numbers of authors, manuscript pages, references, collaborating institutions, the position in the byline of the corresponding author, the country of the corresponding author, and the names of the first and corresponding author. We also calculated the normalized number of citations and corresponding author position. The number of authors, institutions, and countries collaborating on manuscripts published in both JBJS and BJJ increased over time. JBJS published more manuscripts from North America and BJJ published more manuscripts from Europe. In both journals, the percentage of women as first and/or corresponding author increased over time. Trends over the past 30 years have shown increased collaborations with greater citations in manuscripts published in JBJS and BJJ. In the same time period, both journals demonstrated a rise in the percentage of manuscripts with women first and/or corresponding authors, suggesting a decrease in the gender gap

Meta-Analysis of the Alzheimer\u27s Disease Human Brain Transcriptome and Functional Dissection in Mouse Models.

We present a consensus atlas of the human brain transcriptome in Alzheimer\u27s disease (AD), based on meta-analysis of differential gene expression in 2,114 postmortem samples. We discover 30 brain coexpression modules from seven regions as the major source of AD transcriptional perturbations. We next examine overlap with 251 brain differentially expressed gene sets from mouse models of AD and other neurodegenerative disorders. Human-mouse overlaps highlight responses to amyloid versus tau pathology and reveal age- and sex-dependent expression signatures for disease progression. Human coexpression modules enriched for neuronal and/or microglial genes broadly overlap with mouse models of AD, Huntington\u27s disease, amyotrophic lateral sclerosis, and aging. Other human coexpression modules, including those implicated in proteostasis, are not activated in AD models but rather following other, unexpected genetic manipulations. Our results comprise a cross-species resource, highlighting transcriptional networks altered by human brain pathophysiology and identifying correspondences with mouse models for AD preclinical studies