The impact of mutation and gene conversion on the local diversification of antigen genes in African trypanosomes

Patterns of genetic diversity in parasite antigen gene families hold important information about their potential to generate antigenic variation within and between hosts. The evolution of such gene families is typically driven by gene duplication, followed by point mutation and gene conversion. There is great interest in estimating the rates of these processes from molecular sequences for understanding the evolution of the pathogen and its significance for infection processes. In this study, a series of models are constructed to investigate hypotheses about the nucleotide diversity patterns between closely related gene sequences from the antigen gene archive of the African trypanosome, the protozoan parasite causative of human sleeping sickness in Equatorial Africa. We use a hidden Markov model approach to identify two scales of diversification: clustering of sequence mismatches, a putative indicator of gene conversion events with other lower-identity donor genes in the archive, and at a sparser scale, isolated mismatches, likely arising from independent point mutations. In addition to quantifying the respective probabilities of occurrence of these two processes, our approach yields estimates for the gene conversion tract length distribution and the average diversity contributed locally by conversion events. Model fitting is conducted using a Bayesian framework. We find that diversifying gene conversion events with lower-identity partners occur at least five times less frequently than point mutations on variant surface glycoprotein (VSG) pairs, and the average imported conversion tract is between 14 and 25 nucleotides long. However, because of the high diversity introduced by gene conversion, the two processes have almost equal impact on the per-nucleotide rate of sequence diversification between VSG subfamily members. We are able to disentangle the most likely locations of point mutations and conversions on each aligned gene pair

Consensus statement on improving the mental health of high performance athletes

This consensus statement is the product of an international Think Tank on the initiative of the International Society of Sport Psychology. The purpose of the Think Tank was to unify major sport psychology organizations in a discussion of the current status and future challenges of applied and research aspects of athlete mental health. The contributors present six propositions and recommendations to inspire sport organizations and researchers. The propositions are: Mental health is a core component of a culture of excellence; Mental health in a sport context should be better defined; Research on mental health in sport should broaden the scope of assessment; Athlete mental health is a major resource for the whole athletic career and life post-athletic career; The environment can nourish or malnourish athlete mental health; and Mental health is everybody’s business but should be overseen by one or a few specified members. It is recommended that researchers unite to develop a more contextualized definition of athlete mental health and more comprehensive strategies of assessment, as well as join forces with sporting organizations to investigate sustainable elite sport environments and the role of the mental health officer. Sport organizations are advised to recognize athlete mental health as a core component of a healthy elite sport system and a key indicator of their effectiveness, support research initiatives, and to promote the mental health literacy of all their staff while engaging a mental health officer with the responsibility to oversee a support system

Component Hiding Using Identification and Boundary Blurring Techniques

Protecting software from adversarial attacks is extremely important for DoD technologies. When systems are compromised, the possibility exists for recovery costing millions of dollars and countless labor hours. Circuits implemented on embedded systems utilizing FPGA technology are the result of downloading software for instantiating circuits with specific functions or components. We consider the problem of component hiding a form of software protection. Component identification is a well studied problem. However, we use component identification as a metric for driving the cost of reverse engineering to an unreasonable level. We contribute to protection of software and circuitry by implementing a Java based component identification tool. With this tool, we can characterize time required for carrying out adversarial attacks on unaltered boolean circuitry. To counter component identification methods we utilize boundary blurring techniques which are either semantic preserving or semantic changing in order to prevent component identification methods. Furthermore, we will show these techniques can drive adversarial cost to unreasonable levels preventing compromise of critical systems

Mortarboard Review: Montessori-Related Dissertations 2022 – 2023

This article is the first in a series of planned reviews to be published annually that highlight a selection of dissertations. Some aspects of the selection and review methodology may be adjusted in coming issues as the process is refined to maximize the value to the field. Twenty-three Montessori-related dissertations completed during 2021 and 2022 were identified that represented five broad categories based on topic or subject matter. Two dissertations were selected for inclusion in this review because they represent high-quality research in areas that are of particular relevance and value to the field at this time: (a) public Montessori education and issues of equity and intercultural competence and (b) teacher perspectives and technology

Productivity in the mining industry: measurement and interpretation

The measurement and interpretation of productivity frequently presents significantchallenges, especially when conducted at the industry level. In this regard themining industry is no exception. This report identifies measurement andinterpretation issues of relevance to productivity estimates for the mining industryin Australia. Quantitative evidence is presented regarding the effect on miningindustry productivity growth of two important factors: systematic changes in theunderlying quality of natural resource inputs used in mining; and production lags inresponse to increases in capital investment

Feasibility study of the solar scientific instruments for Spacelab/Orbiter

The feasibility and economics of mounting and operating a set of solar scientific instruments in the backup Skylab Apollo Telescope Mount (ATM) hardware was evaluated. The instruments used as the study test payload and integrated into the ATM were: the Solar EUV Telescope/Spectrometer; the Solar Active Region Observing Telescope; and the Lyman Alpha White Light Coronagraph. The backup ATM hardware consists of a central cruciform structure, called the "SPAR', a "Sun End Canister' and a "Multiple Docking Adapter End Canister'. Basically, the ATM hardware and software provides a structural interface for the instruments; a closely controlled thermal environment; and a very accurate attitude and pointing control capability. The hardware is an identical set to the hardware that flow on Skylab

UC-316 Recipe For Disaster

Sugar, Spice, and everything nice or naughty, using the ingredients available to you, you must battle your way out of the bizarre world of chefs and cooks as they attempt to flambe and tenderize you. Whisk, Boil, and Cook your way out of the endless kitchen to secure your way as a true MasterChe