An Empirical Classification Of University Lecturing Styles

The goal of this research was to develop and validate an empirical classification of naturally occurring teaching styles in university undergraduate lecture courses. Teaching style was described in terms of patterns of observable classroom teaching behavior.;In the first study, the classification was developed with reference to an initial sample of 298 university lecturers. Each instructor was observed by student raters, who judged the frequency of occurrence of 100 low-inference behaviours. Student ratings were averaged within classes and eight scale scores were computed. A cluster analysis identified six groups of instructors, with members of each group homogeneous in terms of their classroom teaching behaviour patterns. The replicability of the clusters was assessed within this sample through split-half samples, statistical tests, and a comparison of results based on item and scale scores.;In the second study, the typology was validated by investigating relationships between teaching style and other relevant variables, such as instructor characteristics and attitudes, course characteristics, and global student ratings of teaching effectiveness. For this purpose, a second sample of 135 classes was obtained. Significant differences in the frequencies of the six styles across subject area and course level had been noted in the original sample. These differences in style frequencies were replicated in the second sample with regard to course level but not subject area. Overall elevation of the behavioural scale scores played a major role in determining relationships between teaching style and global student ratings. Instructor characteristics such as years of teaching experience, academic rank, and educational goals and attitudes did not display significant relationships with teaching style.;In the third study, additional validation evidence for the typology was gathered through examination of the stability of teaching styles across courses and across years. It was found that behaviour was relatively stable when courses were at the same academic level (i.e., introductory, general, honours), even if the courses were separated by as much as eight years.;In general there was evidence that the empirical classification approach is a useful method for describing teacher behaviour. It allows a definition of teaching style, or educational treatment, in terms of discrete, observable behaviours

Reduction of speed limit from 110 km/h to 100 km/h on certain roads in South Australia: a preliminary evaluation

In July 2003, the speed limit on approximately 1,100 km of rural arterial roads in South Australia was reduced from 110 km/h to 100 km/h. The crash experience on these roads in the two years before and the two years following the change has been compared with that on other roads where the 100 km/h limit was not changed. It appears that the speed limit reduction has had the effect of reducing casualty crashes by 20 per cent. However, the number of crashes on these roads is small and the time since the change is so short that this estimate is uncertain. It is reasonable to think that in the longer term the change might be anywhere between an increase of 4 per cent and a decrease of 44 per cent. There was a decrease in crashes and casualties on the 100 km/h roads where the speed limit did not change and that has been allowed for in the calculations. At six sites, speed measurements before and after the speed limit reduction were available: an average speed reduction of 2 km/h was foundA.D. Long, C.N. Kloeden, T.P. Hutchinson and A.J. McLea

Rear end crashes

Due to the common occurrence of rear end collisions in South Australia, and the costliness of Compulsory Third Party (CTP) claims associated with them, a study was undertaken into the nature of, and possible countermeasures for, rear end collisions. This study included an analysis of five years of police-reported crash data, an analysis of a sample of rear end crashes investigated as part of the CASR metropolitan in-depth crash study, and a literature review concerned with countermeasures for rear end crashes. The most common factors contributing to these types of crashes are the lack of protection for right turning vehicles and the inadequate allocation of attention by drivers to the driving task. Countermeasures are available for both of these contributing factors. Providing greater protection for right turning vehicles requires road-based countermeasures, while the most promising countermeasure for inadequate allocation of attention is the installation in vehicles of collision avoidance systems. However, the latter countermeasure will only be available after further testing and refinement of current prototype systems.M.R.J. Baldock, A.D. Long, V.L. Lindsay and A.J. McLea

The naturally occurring host defense peptide, LL-37, and its truncated mimetics KE-18 and KR-12 have selected biocidal and antibiofilm activities against Candida albicans, Staphylococcus aureus, and Escherichia coli in vitro

Amongst the recognized classes of naturally occurring antimicrobials, human host defense peptides are an important group with an advantage (given their source) that they should be readily translatable to medicinal products. It is also plausible that truncated versions will display some of the biological activities of the parent peptide, with the benefit that they are less costly to synthesize using solid-phase chemistry. The host defense peptide, LL-37, and two truncated mimetics, KE-18 and KR-12, were tested for their inhibitory effects and antibiofilm properties against Candida albicans, Staphylococcus aureus, and Escherichia coli, microorganisms commonly implicated in biofilm-related infections such as ventilator-associated pneumonia (VAP). Using in silico prediction tools, the truncated peptides KE-18 and KR-12 were selected for minimum inhibitory concentration (MIC) and antibiofilm testing on the basis of their favorable cationicity, hydrophobic ratio, and amphipathicity compared with the parent peptide. Two methods were analyzed for determining peptide efficacy against biofilms; a crystal violet assay and an XTT [2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide] assay. The biocidal activities (measured by MIC) and antibiofilm activities (measured by a crystal violet assay) appeared to be independent. LL-37 had no biocidal action against C. albicans (MIC > 250 μg/ml) but significant effects in both biofilm-prevention and biofilm-inhibition assays. KE-18 and KR-12 yielded superior MIC values against all three microorganisms. Only KE-18 had a significant effect in the biofilm-prevention assay, which persisted even at sub-MICs. Neither of the truncated peptides were active in the biofilm-inhibition assay. KE-18 was shown to bind lipopolysaccharide as effectively as LL-37 and to bind lipoteichoic acid more effectively. None of the peptides showed hemolytic activity against human erythrocytes at the concentrations tested. KE-18 should be considered for further development as a natural peptide-derived therapeutic for prevention of multi-species biofilm-related infections such as VAP

A conserved protein, BcmA, mediates motility, biofilm formation, and host colonisation in Adherent Invasive Escherichia coli

Adherent Invasive Escherichia coli (AIEC) is a non-diarrhoeagenic intestinal E. coli pathotype associated with Crohn’s Disease. AIEC pathogenesis is characterised by biofilm formation, adhesion to and invasion of intestinal epithelial cells, and intracellular replication within epithelial cells and macrophages. Here, we identify and characterise a protein in the prototypical AIEC strain LF82 which is required for efficient biofilm formation and dispersal – LF82_p314. LF82 ΔLF82_314 have defective swimming and swarming motility, indicating LF82_p314 is important for flagellar-mediated motility, and thus surface colonisation and biofilm dispersal. Flagellar morphology and chemotaxis in liquid appear unaffected by deletion of LF82_314, suggesting LF82_p314 does not elicit an effect on flagella biogenesis or environmental sensing. Flagellar motility has been implicated in AIEC virulence, therefore we assessed the role of LF82_p314 in host colonisation using a Caenorhabditis elegans model. We found that LF82 ΔLF82_314 have an impaired ability to colonise the C. elegans compared to wild-type LF82. Phylogenetic analysis showed that LF82_314 is conserved in several major enterobacterial pathogens, and suggests the gene may have been acquired horizontally in several genera. Our data suggests LF82_p314 may be a novel component in the flagellar motility pathway and is a novel determinant of AIEC colonisation. Our findings have potential implications not only for the pathogenesis of Crohn’s Disease, but also for the course of infection in several major bacterial pathogens. We propose a new designation for LF82_314, biofilm coupled to motility A, or bcmA

Venatorbacter cucullus gen. nov sp. nov a novel bacterial predator

A novel Gram-stain negative, aerobic, halotolerant, motile, rod-shaped, predatory bacterium ASxL5T, was isolated from a bovine slurry tank in Nottinghamshire, UK using Campylobacter hyointestinalis as prey. Other Campylobacter species and members of the Enterobacteriaceae were subsequently found to serve as prey. Weak axenic growth on Brain Heart Infusion agar was achieved upon subculture without host cells. The optimal growth conditions were 37°C, at pH 7. Transmission electron microscopy revealed some highly unusual morphological characteristics related to prey availability. Phylogenetic analyses using 16S rRNA gene sequences showed that the isolate was related to members of the Oceanospirillaceae family but could not be classified clearly as a member of any known genus. Whole genome sequencing of ASxL5T confirmed the relationship to members the Oceanospirillaceae. Database searches revealed that several ASxL5T share 16S rRNA gene sequences with several uncultured bacteria from marine, and terrestrial surface and subsurface water. We propose that strain ASxL5T represents a novel species in a new genus. We propose the name Venatorbacter cucullus gen. nov., sp. nov. with ASxL5T as the type strain

Motor Vehicle Collision-Related Emergency Department Visits by Older Adults in the United States

Motor vehicle collisions (MVCs) are the second most common cause of non-fatal injury among U.S. adults age 65 years and older. However, the frequency of emergency department (ED) visits, disposition, pain locations, and pain severity for older adults experiencing MVCs have not previously been described. The authors sought to determine these characteristics using information from two nationally representative data sets

Genetic diversity and selection signatures in maize landraces compared across 50 years of in situ and ex situ conservation

Genomics-based, longitudinal comparisons between ex situ and in situ agrobiodiversity conservation strategies can contribute to a better understanding of their underlying effects. However, landrace designations, ambiguous common names, and gaps in sampling information complicate the identification of matching ex situ and in situ seed lots. Here we report a 50- year longitudinal comparison of the genetic diversity of a set of 13 accessions from the state of Morelos, Mexico, conserved ex situ since 1967 and retrieved in situ from the same donor families in 2017. We interviewed farmer families who donated in situ landraces to understand their germplasm selection criteria. Samples were genotyped by sequencing, producing 74,739 SNPs. Comparing the two sample groups, we show that ex situ and in situ genome-wide diversity was similar. In situ samples had 3.1% fewer SNPs and lower pairwise genetic distances (Fst 0.008–0.113) than ex situ samples (Fst 0.031–0.128), but displayed the same heterozygosity. Despite genome-wide similarities across samples, we could identify several loci under selection when comparing in situ and ex situ seed lots, suggesting ongoing evolution in farmer fields. Eight loci in chromosomes 3, 5, 6, and 10 showed evidence of selection in situ that could be related with farmers’ selection criteria surveyed with focus groups and interviews at the sampling site in 2017, including wider kernels and larger ear size. Our results have implications for ex situ collection resampling strategies and the in situ conservation of threatened landraces

Older US Emergency Department Patients Are Less Likely to Receive Pain Medication Than Younger Patients: Results From a National Survey

The purpose of this study is to determine whether older adults presenting to the Emergency Department (ED) with pain are less likely to receive pain medication than younger adults