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"Simulation-based inference" is often considered a pedagogical strategy for helping students develop inferential reasoning, for example, giving them a visual and concrete reference for deciding whether the observed statistic is unlikely to happen by chance alone when the null hypothesis is true. In this article, we highlight for teachers some implications of different simulation strategies when analyzing two variables. In particular, does it matter whether the simulation models random sampling or random assignment? We present examples from comparing two means and simple linear regression, highlighting the impact on the standard deviation of the null distribution. We also highlight some possible extensions that simulation-based inference easily allows. for this article are available online. [ABSTRACT FROM AUTHOR]

The first complete mitochondrial genome sequencing of Asiatic Water snake or Checkered Keelback or Fowlea piscator (=Xenochrophis piscator) was carried out using Next-Generation Sequencing technology. The complete mitochondrial genome of Asiatic Water snake is 16,999bp long with a base composition of 33% A, 28% T, 12% G and 27% C, with a GC content of 39%. Like the typical snake mitochondrial genome, F. piscator also shows relatively similar mitogenome arrangement comprising 37 genes including 13 protein-coding genes, 22 tRNA genes, two rRNA genes and two non-coding regions or a duplicated control region (D-Loop) along with an origin of replication. Nine genes including eight tRNAs and NAD6 were encoded on the Light or L-strand. Phylogenetic analyses using the complete mitochondrial genome of F. piscator demonstrate a close relationship with the family Colubridae and sub family Natricinae. [ABSTRACT FROM AUTHOR]

The recent simulation-based inference (SBI) movement in algebra-based introductory statistics courses (Stat 101) has provided preliminary evidence of improved student conceptual understanding and retention. However, little is known about whether these positive effects are preferentially distributed across types of students entering the course. We consider how two metrics of Stat 101 student preparation (precourse performance on concept inventory and math ACT score) may or may not be associated with end of course student performance on conceptual inventories. Students across all preparation levels tended to show improvement in Stat 101, but more improvement was observed across all student preparation levels in early versions of a SBI course. Furthermore, students' gains tended to be similar regardless of whether students entered the course with more preparation or less. Recent data on a sample of students using a current version of an SBI course showed similar results, though direct comparison with non-SBI students was not possible. Overall, our analysis provides additional evidence that SBI curricula are effective at improving students' conceptual understanding of statistical ideas postcourse regardless student preparation. Further work is needed to better understand nuances of student improvement based on other student demographics, prior coursework as well as instructor and institutional variables. [ABSTRACT FROM AUTHOR]

An interview with Soma Roy, an associate professor in the Department of Statistics at Cal Poly in San Luis Obispo, California, is presented. She discusses her classroom teaching experience at the Ohio State University as well as the improvement of her teaching style. She also mentions that she is currently teaching introductory statistics.

The article focuses on a research related to anti-carcinogenic activity of Litchi chinensis leaf extract (LCLE) against Ehrlich's ascites carcinoma (EAC) in mice. Topics discussed include potent antileukemic activity against human leukemic cell lines showed by LCLE; detection of apoptosis by flow cytometric analysis; and an increase in cytochrome c oxidase activity for treatment in EAC cells.

The use of simulation-based methods for introducing inferen-ce is growing in popularity for the Stat 101 course, due in part to increasing evidence of the methods ability to improve studen-ts’ statistical thinking. This impact comes from simulation-based methods (a) clearly presenting the overarching logic of inference, (b) strengthening ties between statistics and probability/mathematical concepts, (c) encouraging a focus on the entire research process, (d) facilitating student thinking about advanced statistical concepts, (e) allowing more time to explore, do, and talk about real research and messy data, and (f) acting as a firm-er foundation on which to build statistical intuition. Thus, we argue that simulation-based inference should be an entry point to an undergraduate statistics program for all students, and that simulation-based inference should be used throughout all under-graduate statistics courses. To achieve this goal and fully recognize the benefits of simulation-based inference on the undergraduate statistics program, we will need to break free of historical forces tying undergraduate statistics curricula to mathematics, consider radical and innovative new pedagogical approaches in our courses, fully implement assessment-driven content innovations, and embrace computation throughout the curriculum. [Received December 2014. Revised July 2015] [ABSTRACT FROM PUBLISHER]

Ultrafine nickel oxide nanoparticles were prepared by sol–gel method using a solution of nickel nitrate hexahydrate and ammonium hydroxide and subsequently annealed in air at different temperatures in the range 200–275 °C for different hours to vary the particle sizes. They were characterised for phase, purity, structure and sizes by X-ray diffraction and high-resolution transmission electron microscopy. They were found polycrystalline in nature and possessed face-centred cubic (NaCl-type) structure with lattice parameter varying with annealing temperature. The ultrafine structure clearly revealed the formation of hexagons with average diameter about 5 nm. Ultraviolet–visible absorption spectroscopy was carried out to study the optical properties and for the estimation of the bandgap. The nanoparticles exhibited weak and strong quantum confinement in the size ranges of 10.47–8.47 and 6.57–5 nm. The samples were then investigated through positron annihilation spectroscopy to characterise and closely monitor the evolution of vacancy-type defects and defect clusters during particle growth in the samples. The positron lifetime drastically increased at very low particle sizes, supporting the confinement effects demonstrated by optical absorption studies. The results from coincidence Doppler broadening measurements were consistent and indicated changes also in the electron momentum distribution during the occurrence of these finite size effects in the nanoparticles. [ABSTRACT FROM PUBLISHER]

Purpose: To describe the clinical profile and surgical management of patients with lacrimal sac rhinosporidiosis. Methods: This is a retrospective interventional case series. Eighteen patients, who were clinically diagnosed as isolated lacrimal sac rhinosporidiosis between October 2009 to January 2012, were included in the study. Detailed history, including whether there was exposure to stagnant bathing water, was noted. All patients underwent modified dacryocystorhinostomy (DCR) under general anaesthesia. Result: Out of 18 patients, 14 were male and 4 were female. Rhinosporidiosis was more prevalent in the 25 to 34 years age group. The most common clinical presentation was a doughy swelling over the lacrimal sac area, present in all cases. Twelve patients (66.67%) had a history of bathing in stagnant water. After modified DCR operation, all patients were followed for one year and only two patients had recurrence of their disease. Conclusion: Patients with lacrimal sac rhinosporidiosis usually present with a soft, doughy swelling in the lacrimal sac area. Bathing in stagnant water is a common risk factor. A modified DCR yields excellent outcomes. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses various reports within the issue on topics including an interview with statistics professor Richard De Veaux, statistics education and research.

An introduction is presented in which the editor discusses various reports within the issue on topics including teaching, learning and statistics.