Improved multivariate portmanteau test

A new portmanteau diagnostic test for vector autoregressive moving average (VARMA) models that is based on the determinant of the standardized multivariate residual autocorrelations is derived. The new test statistic may be considered an extension of the univariate portmanteau test statistic suggested by Peňa and Rodríguez (2002) . The asymptotic distribution of the test statistic is derived as well as a chi‐square approximation. However, the Monte–Carlo test is recommended unless the series is very long. Extensive simulation experiments demonstrate the usefulness of this test as well as its improved power performance compared to widely used previous multivariate portmanteau diagnostic check. Two illustrative applications are given.     

Optimization of 4-Substituted Benzenesulfonamide Scaffold To Reverse Acinetobacter baumannii Serum-Adaptive Efflux Associated Antibiotic Tolerance

Acinetobacter baumannii is a nosocomial pathogen of urgent concern for public health due to rising rates of multidrug and pandrug resistance. In the context of environmental cues such as growth in human serum, A. baumannii is known to display adaptive efflux, in which a multitude of efflux-associated genes are upregulated, resulting in efflux-mediated drug tolerance in strains that are otherwise susceptible to antibiotic therapy. Previously, we identified a sulfonamide-containing scaffold molecule (ABEPI1) that reversed serum-associated antibiotic tolerance in A. baumannii. Herein, we present structure-activity relationship studies on 29 newly synthesized analogues. These molecules were characterized for their ability to potentiate multiple antibiotics in serum, reduce serum-associated ethidium bromide efflux and depolarize bacterial cell membranes. In addition, they were assessed for toxicity to mammalian cells. Collectively, these molecules may represent promising potential adjuvants for use in combination with new and existing antibiotics to treat A. baumannii bacterial infections.     

Lost at sea: genetic,oceanographic and meteorological evidence for storm-forced dispersal

For many species, there is broad-scale dispersal of juvenile stages and/or long-distance migration of individuals and hence the processes that drive these various wide-ranging movements have important life-history consequences. Sea turtles are one of these paradigmatic long-distance travellers, with hatchlings thought to be dispersed by ocean currents and adults often shuttling between distant breeding and foraging grounds. Here, we use multi-disciplinary oceanographic, atmospheric and genetic mixed stock analyses to show that juvenile turtles are encountered ‘downstream’ at sites predicted by currents. However, in some cases, unusual occurrences of juveniles are more readily explained by storm events and we show that juvenile turtles may be displaced thousands of kilometres from their expected dispersal based on prevailing ocean currents. As such, storms may be a route by which unexpected areas are encountered by juveniles which may in turn shape adult migrations. Increased stormy weather predicted under climate change scenarios suggests an increasing role of storms in dispersal of sea turtles and other marine groups with life-stages near the ocean surface.     

Topological model of alkali germanate glasses and exploration of the germanate anomaly

Germanate glasses are of particular interest for their excellent optical properties as well as their abnormal structural changes that appear with the addition of modifiers, giving rise to the so-called germanate anomaly. This anomaly refers to the nonmonotonic compositional scaling of properties exhibited by alkali germanate glasses and has been studied with various spectroscopy techniques. However, it has been difficult to understand its atomic scale origin, especially since the germanium nucleus is not easily observed by nuclear magnetic resonance. To gain insights into the mechanisms of the germanate anomaly, we have constructed a structural model using statistical mechanics and topological constraint theory to provide an accurate prediction of alkali germanate glass properties. The temperature onsets for the rigid bond constraints are deduced from in situ Brillouin light scattering, and the number of constraints is shown to be accurately calculable using statistical methods. The alkali germanate model accurately captures the effect of the germanate anomaly on glass transition temperature, liquid fragility, and Young's modulus. We also reveal that compositional variations in the glass transition temperature and Young's modulus are governed by the O–Ge–O angular constraints, whereas the variations in fragility are governed by the Ge–O radial constraints.     

A home among the gum trees: the Victorian Sanatorium for consumptives,Echuca and Mount Macedon

The history of the treatment of tuberculosis in Australia has largely been focused on the development of medical treatments, the architectural features of custom-built sanatoria and the human impact of the disease in the nineteenth and early twentieth centuries. These discussions often mention contemporary debates amongst medical men and the laity regarding the best treatment, but the influence of medical climatology in deciding where medical facilities should be placed is often overlooked. The first sanatorium in the Colony of Victoria had two branches: Echuca and Mount Macedon. These two locations differ in terms of altitude, the surrounding forest and meteorological variation. Yet, both sites were considered suitable at the time for the location of a sanatorium, possibly due to the health-promoting and aesthetic aspects of nearby eucalypt forests. This article explores why they may at first modernly appear to be substantially different locations, but contemporary medical climatology emphasised their similarities.     

ERP Simulation Effects on Knowledge and Attitudes of Experienced Users

ABSTRACT

Best-in-class organizations recognize that knowledge management provides a competitive advantage. Opportunities to share knowledge enhance knowledge sharing attitudes. Organizations use training to facilitate knowledge and acclimate novice employees to Enterprise Resource Planning (ERP) systems. Most ERP functional training leverages explicit codified knowledge. Without collaborative opportunities between departments, allowing users to interact and exchange internalized knowledge and skills, information remains untapped. Prior research explored the impact of ERPsim on knowledge, skills, and attitudes, but failed to model construct relationships. This work assesses if a business simulation can be used to mimic Social Cognition Theory and enhance knowledge and attitude among experienced employees. Paired sample T-tests confirmed significant differences in means across constructs. Additionally, PLS Path Modeling investigated and confirmed a relationship between knowledge and skills constructs with attitude. Findings suggest ERPsim might be beneficial to diffuse knowledge and skills among experienced users in the workplace, while positively influencing attitudes.     

The effects of multimedia-enhanced instruction on the vocabulary of English-language learners and non-English-language learners in pre-kindergarten through second grade.

This study compared traditional and multimedia-enhanced read-aloud vocabulary instruction and investigated whether the effects differed for English-language learners (ELLs) and non-English-language learners (non-ELLs). Results indicate that although there was no added benefit of multimedia-enhanced instruction for non-ELLs, there was a positive effect for ELLs on a researcher-designed measure and on a measure of general vocabulary knowledge. Furthermore, for children in the multimedia-enhanced condition, the gap between non-ELLs and ELLs in knowledge of instructional words was closed, and the gap in general vocabulary knowledge was narrowed. The multimedia support did not negatively impact non-ELLs, indicating the potential of multimedia-enhanced vocabulary instruction for ELLs in inclusive settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)