High School Math Curriculum, Student\u27s Course Selection and Education Outcomes

Twenty-one states are increasing the requirements for a high school diploma so that all students graduate college-ready. The new graduation requirements include completion of Algebra, Geometry and Algebra II. Before this recent set of reforms, states had graduation requirements related to the number of math credits, irrespective of math course content. To quantify the potential impact of requiring Algebra, Geometry and Algebra II for high school graduation on educational attainment and math knowledge, I develop a dynamic, discrete choice model of high school attendance, math course selection and educational attainment. I estimate the parameters of the model using data from NELS:88/2000 under the old policy and simulate behavior under the new graduation requirement. Model simulations show that educational attainment at age 18 is very responsive to the policy change, but college completion by age 25 is less so. The on-time high school graduation rate falls from 84 to 59 percent, and the proportion of students opting for a GED during the four years of high school increases from 2 to 20 percent. The overall proportion of individuals who earn an advanced degree remains roughly constant, moving from 37 to 36 percent

Bayesian estimation of in-game home team win probability for National Basketball Association games

Maddox, et al. (2022) establish a new win probability estimation for college basketball and compared the results with previous methods of Stern (1994), Desphande and Jensen (2016) and Benz (2019). This paper proposes modifications to the approach of Maddox, et al. (2022) for the NBA game and investigates the performance of the model. Enhancements to the model are developed, and the resulting adjusted model is compared with existing methods and to the ESPN counterpart. To illustrate utility, all methods are applied to the November 23, 2019 game between the Chicago Bulls and Charlotte Hornets.Comment: 15 pages, 7 figures, 5 tables. arXiv admin note: text overlap with arXiv:2204.1177

A New Method for Interfacing Unsuited Subjects to Overhead Suspension Partial Gravity Simulators

The purpose of performing unsuited testing as part of a reduced gravity extravehicular (EVA) suited human performance research program is to define baseline performance. These results are then coupled with suited test results to evaluate how the suit system affects human performance at reduced gravity. The primary drawback to this approach is that previous studies used notably different systems to interface suited and unsuited subjects to overhead-suspension, partial-gravity simulators. A spreader bar (SB) assembly previously used for unsuited tests allowed limited pitch and roll of the subject, whereas the gimbal for suited tests allowed more pitch and roll, although the mass distribution led to large moments of inertia in the yaw axis. It is hypothesized that use of the same methods for offload of both unsuited and suited subjects is needed to make meaningful comparisons. A new gimbal (GIM) was designed with the idea that it could function with both suited and unsuited subjects. GIM was designed to minimize mass and moments of inertia and to be adjustable to co-locate the 3 axes of rotation with the subject s center of gravity. OBJECTIVE: To evaluate human performance differences between SB and GIM. METHODS: Ten unsuited subjects were off-loaded to 1/6-g using both interfaces. Subjects completed tasks including overground and treadmill ambulation, picking up objects, shoveling, postural stability, range of motion testing, and recovery from the kneeling and prone positions. Metabolic, biomechanical, and/or subjective data were collected based on task. RESULTS: Initial analyses suggest that subjects completed all tasks with lower levels of compensation and a more terrestrial approach to movement when suspended via GIM. With SB, subjects were not able to fall or get into a prone position and had increased difficulty both retrieving objects off the floor and with overground ambulation, especially at gait initiation, because they were unable to bend their torso. GIM shows promise as a new method

Type six secretion system of Bordetella bronchiseptica and adaptive immune components limit intracellular survival during infection

The Type Six Secretion System (T6SS) is required for Bordetella bronchiseptica cytotoxicity, cytokine modulation, infection, and persistence. However, one-third of recently sequenced Bordetella bronchiseptica strains of the predominantly human-associated Complex IV have lost their T6SS through gene deletion or degradation. Since most human B. bronchiseptica infections occur in immunocompromised patients, we determine here whether loss of Type Six Secretion is beneficial to B. bronchiseptica during infection of immunocompromised mice. Infection of mice lacking adaptive immunity (Rag1-/- mice) with a T6SS-deficient mutant results in a hypervirulent phenotype that is characterized by high numbers of intracellular bacteria in systemic organs. In contrast, wild-type B. bronchiseptica kill their eukaryotic cellular hosts via a T6SS-dependent mechanism that prevents survival in systemic organs. High numbers of intracellular bacteria recovered from immunodeficient mice but only low numbers from wild-type mice demonstrates that B. bronchiseptica survival in an intracellular niche is limited by B and T cell responses. Understanding the nature of intracellular survival during infection, and its effects on the generation and function of the host immune response, are important to contain and control the spread of Bordetella-caused disease.Liron Bendor, Laura S. Weyrich, Bodo Linz, Olivier Y. Rolin, Dawn L. Taylor, Laura L. Goodfield, William E. Smallridge, Mary J. Kennett, Eric T. Harvil

Horizontally acquired divergent O-antigen contributes to escape from cross-immunity in the classical bordetellae

BACKGROUND: Horizontal gene transfer (HGT) allows for rapid spread of genetic material between species, increasing genetic and phenotypic diversity. Although HGT contributes to adaptation and is widespread in many bacteria, others show little HGT. This study builds on previous work to analyze the evolutionary mechanisms contributing to variation within the locus encoding a prominent antigen of the classical bordetellae. RESULTS: We observed amongst classical bordetellae discrete regions of the lipopolysaccharide O-antigen locus with higher sequence diversity than the genome average. Regions of this locus had less than 50% sequence similarity, low dN/dS ratios and lower GC content compared to the genome average. Additionally, phylogenetic tree topologies based on genome-wide SNPs were incongruent with those based on genes within these variable regions, suggesting portions of the O-antigen locus may have been horizontally transferred. Furthermore, several predicted recombination breakpoints correspond with the ends of these variable regions. To examine the evolutionary forces that might have selected for this rare example of HGT in bordetellae, we compared in vitro and in vivo phenotypes associated with different O-antigen types. Antibodies against O1- and O2-serotypes were poorly cross-reactive, and did not efficiently kill or mediate clearance of alternative O-type bacteria, while a distinct and poorly immunogenic O-antigen offered no protection against colonization. CONCLUSIONS: This study suggests that O-antigen variation was introduced to the classical bordetellae via HGT through recombination. Additionally, genetic variation may be maintained within the O-antigen locus because it can provide escape from immunity to different O-antigen types, potentially allowing for the circulation of different Bordetella strains within the same host population

Effects of Noise on Ecological Invasion Processes: Bacteriophage-mediated Competition in Bacteria

Pathogen-mediated competition, through which an invasive species carrying and transmitting a pathogen can be a superior competitor to a more vulnerable resident species, is one of the principle driving forces influencing biodiversity in nature. Using an experimental system of bacteriophage-mediated competition in bacterial populations and a deterministic model, we have shown in [Joo et al 2005] that the competitive advantage conferred by the phage depends only on the relative phage pathology and is independent of the initial phage concentration and other phage and host parameters such as the infection-causing contact rate, the spontaneous and infection-induced lysis rates, and the phage burst size. Here we investigate the effects of stochastic fluctuations on bacterial invasion facilitated by bacteriophage, and examine the validity of the deterministic approach. We use both numerical and analytical methods of stochastic processes to identify the source of noise and assess its magnitude. We show that the conclusions obtained from the deterministic model are robust against stochastic fluctuations, yet deviations become prominently large when the phage are more pathological to the invading bacterial strain.Comment: 39 pages, 7 figure

Blood or Serum Exposure Induce Global Transcriptional Changes, Altered Antigenic Profile, and Increased Cytotoxicity by Classical Bordetellae

The classical bordetellae sense and respond to a variety of environments outside and within their mammalian hosts. By causing inflammation and tissue damage, we reasoned that bordetellae are likely to encounter components of blood and/or serum during the course of a respiratory infection, and that detecting and responding to these would be advantageous. Therefore, we hypothesized that classical bordetellae have the ability to sense and respond to blood or serum. Blood or serum exposure resulted in substantial transcriptional changes in Bordetella bronchiseptica, including enhanced expression of many virulence-associated genes. Exposure to blood or serum additionally elicited production of multiple antigens not otherwise detectable, and led to increased bacterial cytotoxicity against macrophages. Transcriptional responses to blood/serum were observed in a Bvg− phase-locked mutant, indicating that the response is not solely dependent on a functional BvgAS system. Similar transcriptional responses to blood/serum were observed for the other classical bordetellae, Bordetella pertussis and Bordetella parapertussis. These data suggest the classical bordetellae respond to signals present in blood and serum by changing their behavior in ways that likely contribute to their remarkable success, via effects on pathogenesis, persistence and/or transmission between hosts

Boolean network simulations for life scientists

Modern life sciences research increasingly relies on computational solutions, from large scale data analyses to theoretical modeling. Within the theoretical models Boolean networks occupy an increasing role as they are eminently suited at mapping biological observations and hypotheses into a mathematical formalism. The conceptual underpinnings of Boolean modeling are very accessible even without a background in quantitative sciences, yet it allows life scientists to describe and explore a wide range of surprisingly complex phenomena. In this paper we provide a clear overview of the concepts used in Boolean simulations, present a software library that can perform these simulations based on simple text inputs and give three case studies. The large scale simulations in these case studies demonstrate the Boolean paradigms and their applicability as well as the advanced features and complex use cases that our software package allows. Our software is distributed via a liberal Open Source license and is freely accessible fro

O Antigen Allows B. parapertussis to Evade B. pertussis Vaccine–Induced Immunity by Blocking Binding and Functions of Cross-Reactive Antibodies

Although the prevalence of Bordetella parapertussis varies dramatically among studies in different populations with different vaccination regimens, there is broad agreement that whooping cough vaccines, composed only of B. pertussis antigens, provide little if any protection against B. parapertussis. In C57BL/6 mice, a B. pertussis whole-cell vaccine (wP) provided modest protection against B. parapertussis, which was dependent on IFN-γ. The wP was much more protective against an isogenic B. parapertussis strain lacking O-antigen than its wild-type counterpart. O-antigen inhibited binding of wP–induced antibodies to B. parapertussis, as well as antibody-mediated opsonophagocytosis in vitro and clearance in vivo. aP–induced antibodies also bound better in vitro to the O-antigen mutant than to wild-type B. parapertussis, but aP failed to confer protection against wild-type or O antigen–deficient B. parapertussis in mice. Interestingly, B. parapertussis–specific antibodies provided in addition to either wP or aP were sufficient to very rapidly reduce B. parapertussis numbers in mouse lungs. This study identifies a mechanism by which one pathogen escapes immunity induced by vaccination against a closely related pathogen and may explain why B. parapertussis prevalence varies substantially between populations with different vaccination strategies