Predicting STEM Achievement with Learning Management System Data: Prediction Modeling and a Test of an Early Warning System

ABSTRACT Learning management systems log users' behaviors, which can be used to predict achievement in a course. This paper examines the implications of data representations (e.g., dichotomous vs. count vs. principled, per learning theory) and applies forward selection algorithms to predict achievement in a biology course. Accuracy is compared across models. The paper closes with a description of an ongoing experiment that employs the prediction model, tests how multiple versions of an early alert message impact students' access of learning resources, and compares the influence of messaging approaches related to personalization and feedback

Multilocus Sequence Typing as a Replacement for Serotyping in Salmonella enterica

Salmonella enterica subspecies enterica is traditionally subdivided into serovars by serological and nutritional characteristics. We used Multilocus Sequence Typing (MLST) to assign 4,257 isolates from 554 serovars to 1092 sequence types (STs). The majority of the isolates and many STs were grouped into 138 genetically closely related clusters called eBurstGroups (eBGs). Many eBGs correspond to a serovar, for example most Typhimurium are in eBG1 and most Enteritidis are in eBG4, but many eBGs contained more than one serovar. Furthermore, most serovars were polyphyletic and are distributed across multiple unrelated eBGs. Thus, serovar designations confounded genetically unrelated isolates and failed to recognize natural evolutionary groupings. An inability of serotyping to correctly group isolates was most apparent for Paratyphi B and its variant Java. Most Paratyphi B were included within a sub-cluster of STs belonging to eBG5, which also encompasses a separate sub-cluster of Java STs. However, diphasic Java variants were also found in two other eBGs and monophasic Java variants were in four other eBGs or STs, one of which is in subspecies salamae and a second of which includes isolates assigned to Enteritidis, Dublin and monophasic Paratyphi B. Similarly, Choleraesuis was found in eBG6 and is closely related to Paratyphi C, which is in eBG20. However, Choleraesuis var. Decatur consists of isolates from seven other, unrelated eBGs or STs. The serological assignment of these Decatur isolates to Choleraesuis likely reflects lateral gene transfer of flagellar genes between unrelated bacteria plus purifying selection. By confounding multiple evolutionary groups, serotyping can be misleading about the disease potential of S. enterica. Unlike serotyping, MLST recognizes evolutionary groupings and we recommend that Salmonella classification by serotyping should be replaced by MLST or its equivalents

Spinoza nella cultura del Novecento. Percorsi attraverso la letteratura e le arti.

Con metodologie e orientamenti interpretativi diversi (alcuni di taglio più storico, o storiografico, altri di impostazione più spiccatamente teoretica) i saggi raccolti in questo volume si propongono di mettere a fuoco in che modo, nel variegato panorama culturale del Novecento, la presenza del pensiero, dell’opera e della vicenda umana di Spinoza abbia inciso nella composizione di un testo letterario o poetico, o sull’ispirazione di una creazione artistica, sia questa di tipo pittorico, teatrale o cinematografico. L’intento che accomuna i contributi qui presentati è quello di indagare quanto risulti profonda, in sostanza, la ricezione (diretta o indiretta) del pensiero dell’autore da parte di letterati, artisti, poeti del XX secolo prendendo le distanze dalle formule stereotipate un tempo tendenti ad appiattire l’immagine di Spinoza su quella tradizionale del filosofo del «metodo geometrico», offrendo spunti, suggestioni, percorsi anche al lettore non specialista

Genomic diversity of Salmonella enterica - The UoWUCC 10K genomes project

Background: Most publicly available genomes of Salmonella enterica are from human disease in the US and the UK, or from domesticated animals in the US. Methods: Here we describe a historical collection of 10,000 strains isolated between 1891-2010 in 73 different countries. They encompass a broad range of sources, ranging from rivers through reptiles to the diversity of all S. enterica isolated on the island of Ireland between 2000 and 2005. Genomic DNA was isolated, and sequenced by Illumina short read sequencing. Results: The short reads are publicly available in the Short Reads Archive. They were also uploaded to EnteroBase, which assembled and annotated draft genomes. 9769 draft genomes which passed quality control were genotyped with multiple levels of multilocus sequence typing, and used to predict serovars. Genomes were assigned to hierarchical clusters on the basis of numbers of pair-wise allelic differences in core genes, which were mapped to genetic Lineages within phylogenetic trees. Conclusions: The University of Warwick/University College Cork (UoWUCC) project greatly extends the geographic sources, dates and core genomic diversity of publicly available S. enterica genomes. We illustrate these features by an overview of core genomic Lineages within 33,000 publicly available Salmonella genomes whose strains were isolated before 2011. We also present detailed examinations of HC400, HC900 and HC2000 hierarchical clusters within exemplar Lineages, including serovars Typhimurium, Enteritidis and Mbandaka. These analyses confirm the polyphyletic nature of multiple serovars while showing that discrete clusters with geographical specificity can be reliably recognized by hierarchical clustering approaches. The results also demonstrate that the genomes sequenced here provide an important counterbalance to the sampling bias which is so dominant in current genomic sequencing