Bayesian chronological modeling of SunWatch, a fort ancient village in Dayton, Ohio

Radiocarbon results from houses, pits, and burials at the SunWatch site, Dayton, Ohio, are presented within an interpretative Bayesian statistical framework. The primary model incorporates dates from archaeological features in an unordered phase and uses charcoal outlier modeling (Bronk Ramsey 2009b) to account for issues of wood charcoal 14C dates predating their context. The results of the primary model estimate occupation lasted for 1–245 yr (95% probability), starting in cal AD 1175–1385 (95% probability) and ending in cal AD 1330–1470 (95% probability). An alternative model was created by placing the 14C dates into two unordered phases corresponding with horizontal stratigraphic relationships or distinct groups of artifacts thought to be temporally diagnostic. The results of the alternative model further suggest that there is some temporal separation between Group 1 and Group 2, which seems more likely in the event of a multicomponent occupation. Overall, the modeling results provide chronology estimates for SunWatch that are more accurate and precise than that provided in earlier studies. While it is difficult to determine with certainty if SunWatch had a single-component or multicomponent occupation, it is clear that SunWatch’s occupation lasted until the second half of the AD 1300s

Proving Termination Starting from the End

We present a novel technique for proving program termination which introduces a new dimension of modularity. Existing techniques use the program to incrementally construct a termination proof. While the proof keeps changing, the program remains the same. Our technique goes a step further. We show how to use the current partial proof to partition the transition relation into those behaviors known to be terminating from the current proof, and those whose status (terminating or not) is not known yet. This partition enables a new and unexplored dimension of incremental reasoning on the program side. In addition, we show that our approach naturally applies to conditional termination which searches for a precondition ensuring termination. We further report on a prototype implementation that advances the state-of-the-art on the grounds of termination and conditional termination.Comment: 16 page

Ranking Templates for Linear Loops

We present a new method for the constraint-based synthesis of termination arguments for linear loop programs based on linear ranking templates. Linear ranking templates are parametrized, well-founded relations such that an assignment to the parameters gives rise to a ranking function. This approach generalizes existing methods and enables us to use templates for many different ranking functions with affine-linear components. We discuss templates for multiphase, piecewise, and lexicographic ranking functions. Because these ranking templates require both strict and non-strict inequalities, we use Motzkin's Transposition Theorem instead of Farkas Lemma to transform the generated $\exists\forall$-constraint into an $\exists$-constraint.Comment: TACAS 201

Long range absorption in the scattering of 6He on 208Pb and 197Au at 27 MeV

Quasi-elastic scattering of 6He at E_lab=27 MeV from 197Au has been measured in the angular range of 6-72 degrees in the laboratory system employing LEDA and LAMP detection systems. These data, along with previously analysed data of 6He + 208Pb at the same energy, are analyzed using Optical Model calculations. The role of Coulomb dipole polarizability has been investigated. Large imaginary diffuseness parameters are required to fit the data. This result is an evidence for long range absorption mechanisms in 6He induced reactions.Comment: 10 pages, 10 figures, minor corrections. To appear in Nucl. Phys.

A flexible approach to introductory programming : engaging and motivating students

© 2019 Copyright is held by the owner/author(s). In this paper, we consider an approach to supporting students of Computer Science as they embark upon their university studies. The transition to Computer Science can be challenging for students, and equally challenging for those teaching them. Issues that are unusual – if not unique – to teaching computing at this level include • the wide variety in students background, varying from no prior experience to extensive development practice; • the positives and negatives of dealing with self-taught hobbyists who may developed buggy mental models of the task in hand and are not aware of the problem; • the challenge of getting students to engage with material that includes extensive practical element; • the atypical profile of a computing cohort, with typically 80%+ male students. The variation in background includes the style of prior academic experience, with some students coming from traditional level 3 (i.e. A-levels), some through more vocational routes (e.g. B-Tech, though these have changed in recent years), through to those from experiential (work based) learning. Technical background varies from science, mathematical and computing experience, to no direct advanced technical or scientific experience. A further issue is students’ attainment and progression within higher education, where the success and outcomes in computer science has been identified as particularly problematic. Computer Science has one the worst records for retention (i.e. students leaving with no award, or a lower award than that originally applied for), and the second worst for attainment (i.e. achieving a good degree, that being defined as a first or a 2:1). One way to attempt to improve these outcomes is by identifying effective ways to improve student engagement. This can be through appropriate motivators – though then the balance of extrinsic versus intrinsic motivation becomes critical. In this paper, we consider how to utilize assessment – combining the formative and summative aspects - as a substitute for coarser approaches based on attendance monitoring

Collaborative International Research in Clinical and Longitudinal Experience Study in NMOSD

Objective To develop a resource of systematically collected, longitudinal clinical data and biospecimens for assisting in the investigation into neuromyelitis optica spectrum disorder (NMOSD) epidemiology, pathogenesis, and treatment. Methods To illustrate its research-enabling purpose, epidemiologic patterns and disease phenotypes were assessed among enrolled subjects, including age at disease onset, annualized relapse rate (ARR), and time between the first and second attacks. Results As of December 2017, the Collaborative International Research in Clinical and Longitudinal Experience Study (CIRCLES) had enrolled more than 1,000 participants, of whom 77.5% of the NMOSD cases and 71.7% of the controls continue in active follow-up. Consanguineous relatives of patients with NMOSD represented 43.6% of the control cohort. Of the 599 active cases with complete data, 84% were female, and 76% were anti-AQP4 seropositive. The majority were white/Caucasian (52.6%), whereas blacks/African Americans accounted for 23.5%, Hispanics/ Latinos 12.4%, and Asians accounted for 9.0%. The median age at disease onset was 38.4 years, with a median ARR of 0.5. Seropositive cases were older at disease onset, more likely to be black/African American or Hispanic/Latino, and more likely to be female. Conclusions Collectively, the CIRCLES experience to date demonstrates this study to be a useful and readily accessible resource to facilitate accelerating solutions for patients with NMOSD

A flexible approach to introductory programming : engaging and motivating students

© 2019 Copyright is held by the owner/author(s). In this paper, we consider an approach to supporting students of Computer Science as they embark upon their university studies. The transition to Computer Science can be challenging for students, and equally challenging for those teaching them. Issues that are unusual – if not unique – to teaching computing at this level include • the wide variety in students background, varying from no prior experience to extensive development practice; • the positives and negatives of dealing with self-taught hobbyists who may developed buggy mental models of the task in hand and are not aware of the problem; • the challenge of getting students to engage with material that includes extensive practical element; • the atypical profile of a computing cohort, with typically 80%+ male students. The variation in background includes the style of prior academic experience, with some students coming from traditional level 3 (i.e. A-levels), some through more vocational routes (e.g. B-Tech, though these have changed in recent years), through to those from experiential (work based) learning. Technical background varies from science, mathematical and computing experience, to no direct advanced technical or scientific experience. A further issue is students’ attainment and progression within higher education, where the success and outcomes in computer science has been identified as particularly problematic. Computer Science has one the worst records for retention (i.e. students leaving with no award, or a lower award than that originally applied for), and the second worst for attainment (i.e. achieving a good degree, that being defined as a first or a 2:1). One way to attempt to improve these outcomes is by identifying effective ways to improve student engagement. This can be through appropriate motivators – though then the balance of extrinsic versus intrinsic motivation becomes critical. In this paper, we consider how to utilize assessment – combining the formative and summative aspects - as a substitute for coarser approaches based on attendance monitoring

Hoop conjecture for colliding black holes : non-time-symmetric initial data

The hoop conjecture is well confirmed in momentarily static spaces, but it has not been investigated systematically for the system with relativistic motion. To confirm the hoop conjecture for non-time-symmetric initial data, we consider the initial data of two colliding black holes with momentum and search an apparent horizon that encloses two black holes. In testing the hoop conjecture, we use two definitions of gravitational mass : one is the ADM mass and the other is the quasi-local mass defined by Hawking. Although both definitions of gravitational mass give fairly consistent picture of the hoop conjecture, the hoop conjecture with the Hawking mass can judge the existence of an apparent horizon for wider range of parameters of the initial data compared to the ADM mass.Comment: 15pages, 4 figure

Disease-specific, neurosphere-derived cells as models for brain disorders

There is a pressing need for patient-derived cell models of brain diseases that are relevant and robust enough to produce the large quantities of cells required for molecular and functional analyses. We describe here a new cell model based on patient-derived cells from the human olfactory mucosa, the organ of smell, which regenerates throughout life from neural stem cells. Olfactory mucosa biopsies were obtained from healthy controls and patients with either schizophrenia, a neurodevelopmental psychiatric disorder, or Parkinson's disease, a neurodegenerative disease. Biopsies were dissociated and grown as neurospheres in defined medium. Neurosphere-derived cell lines were grown in serum-containing medium as adherent monolayers and stored frozen. By comparing 42 patient and control cell lines we demonstrated significant disease-specific alterations in gene expression, protein expression and cell function, including dysregulated neurodevelopmental pathways in schizophrenia and dysregulated mitochondrial function, oxidative stress and xenobiotic metabolism in Parkinson's disease. The study has identified new candidate genes and cell pathways for future investigation. Fibroblasts from schizophrenia patients did not show these differences. Olfactory neurosphere-derived cells have many advantages over embryonic stem cells and induced pluripotent stem cells as models for brain diseases. They do not require genetic reprogramming and they can be obtained from adults with complex genetic diseases. They will be useful for understanding disease aetiology, for diagnostics and for drug discovery

An Up-to-date Assessment of US Prostate Cancer Incidence Rates by Stage and Race: A Novel Approach Combining Multiple Imputation with Age and Delay Adjustment

Background: In the USA, it is unknown whether metastatic prostate cancer incidence has continued to increase and whether racial differences have persisted. Objective: Combining multiple imputation with age and delay adjustment, we provide an up-to-date, comprehensive assessment of US prostate cancer incidence trends by stage and race. Design, setting, and participants: From Surveillance Epidemiology and End Results (SEER)-18, 774 240 prostate cancer cases were diagnosed during 2004–2017. Outcome measurements and statistical analysis: Multiple imputation assigned prostate cancer stage to the 4.7% of cases with missing stage, which varied by year and race-ethnicity. SEER delay factors adjusted case counts to anticipated future data corrections. Twenty datasets were imputed, and Rubin's rules were used for summary estimation. Overall and stage-specific rates were estimated and stratified by race and age group. Joinpoint software identified significant temporal changes and estimated annual percentage changes. We compared these estimates without multiple imputation and delay adjustment. Results and limitations: Metastatic prostate cancer incidence increased during 2011–2017, with an annual percentage change of 5.5. This was followed by increases in localized and regional disease since 2014. Non-Hispanic black men continued to have the highest incidence, especially for metastatic disease. The increasing rate of metastatic prostate cancer in non-Hispanic white men aged 50–74 yr accelerated recently, and the incidence was 56% higher in 2017 than in 2004. Rates without multiple imputation and delay adjustment were quantitatively and qualitatively different. This observational study is unable to assign causes to observed changes in prostate cancer incidence. Conclusions: Multiple imputation and delay adjustment are essential for portraying accurately stage- and race-specific prostate cancer incidence as clinical practice evolves. Patient summary: In the USA, diagnosis of prostate cancer that has spread to distant sites (metastatic disease) continues to increase. Black men continue to have higher risks of being diagnosed with metastatic prostate cancer than other race-ethnicities. In the USA, metastatic prostate cancer incidence rates have continued to increase through 2017, and local and regional disease rates have also increased since 2014. Racial differences persist, with non-Hispanic Black men being at the highest risk