Motivating Students by Active Learning in the History Classroom

The highest challenge we face as classroom teachers is to motivate our students to love history as we do, and to be joyously involved with the texts, themes, issues, and questions of history that interest and excite us. Although our students may seem less well motivated or prepared these days, ultimately the responsibility for their motivation rests with us. The purpose of this article is to suggest several practical strategies for involving students more actively in our history classrooms as a way of instilling in them more responsibility for their own learning, and, therefore, a greater love of history

Impact of the wasting disease pathogen, Labryrinthula on the photobiology of eelgrass Zostera marina

Labyrinthula zosterae is clearly shown to be a primary pathogen of eelgrass Zostera marina L., not merely a secondary infection of senescent leaves or an indication of decomposition. The results of this investigation using a Diving-PAM fluorometer indicate that the regions of tissue photosynthetically compromised by Labyrinthula are substantially larger than previously thought. Labyrinthula moves through Zostera marina tissue at a rate of up to 0.8 mm h–1 during daylight periods. The photosynthetic efficiency of apparently healthy green leaf tissue can be reduced by almost 50% in areas up to 3 mm from a necrotic region infected with Labyrinthula. Once a necrotic spot expands to bisect the eelgrass leaf, the condition of all acropetal tissue is diminished; leaf tissue up to 5 cm away has severely reduced photosynthetic activity

Doppler Probe of Accretion onto a T Tauri star

The YY Ori stars are T Tauri stars with prominent time-variable redshifted absorption components that flank certain emission lines. One of the brightest in this class is S CrA, a visual double star. We have obtained a series of high-resolution spectra of the two components during four nights with the UVES spectrograph at the Very Large Telescope. We followed the spectral changes occurring in S CrA to derive the physical structure of the accreting gas. We found that both stars are very similar with regard to surface temperature, radius, and mass. Variable redshifted absorption components are particularly prominent in the SE component. During one night, this star developed a spectrum unique among the T Tauri stars: extremely strong and broad redshifted absorption components appeared in many lines of neutral and ionized metals, in addition to those of hydrogen and helium. The absorption depths of cooler, low ionization lines peak at low velocities - while more highly ionized lines have peak absorption depths at high velocities. The different line profiles indicate that the temperature and density of the accretion stream increase as material approaches the star. We derive the physical conditions of the flow at several points along the accretion funnel directly from the spectrum of the infalling gas. We estimated mass accretion rates of about 10^(-7) solar masses per year, which is similar to that derived from the relation based on the strength of H alpha emission line. This is the first time the density and temperature distributions in accretion flows around a T Tauri star have been inferred from observations. Compared with predictions from standard models of accretion in T Tauri stars, which assume a dipole stellar magnetic field, we obtained higher densities and a steeper temperature rise toward the star.Comment: Replaces 1408.1846 4 pages, 4 figures. Appears in Astronomy and Astrophysics, 201

Genomic plasticity and rapid host switching can promote the evolution of generalism : a case study in the zoonotic pathogen Campylobacter

This work was supported by the Biotechnology and Biological Sciences Research Council (BBSRC) grant BB/I02464X/1, the Medical Research Council (MRC) grants MR/M501608/1 and MR/L015080/1, and the Wellcome Trust grant 088786/C/09/Z. GM was supported by a NISCHR Health Research Fellowship (HF-14–13).Peer reviewedPublisher PD

Combining the Performance Strengths of the Logistic Regression and Neural Network Models: A Medical Outcomes Approach

The assessment of medical outcomes is important in the effort to contain costs, streamline patient management, and codify medical practices. As such, it is necessary to develop predictive models that will make accurate predictions of these outcomes. The neural network methodology has often been shown to perform as well, if not better, than the logistic regression methodology in terms of sample predictive performance. However, the logistic regression method is capable of providing an explanation regarding the relationship(s) between variables. This explanation is often crucial to understanding the clinical underpinnings of the disease process. Given the respective strengths of the methodologies in question, the combined use of a statistical (i.e., logistic regression) and machine learning (i.e., neural network) technology in the classification of medical outcomes is warranted under appropriate conditions. The study discusses these conditions and describes an approach for combining the strengths of the models

Customer-oriented NPD models for entrepreneurial firms

New Product Development (NPD) is an underutilised methodology in New Zealand. In this paper the authors review the literature on New Product Development, NPD theory and methods for early stage product design and development to make it better understood to SMEs.<br /

The Value of Native Plants and Local Production in an Era of Global Agriculture

For addressing potential food shortages, a fundamental tradeoff exists between investing more resources to increasing productivity of existing crops, as opposed to increasing crop diversity by incorporating more species. We explore ways to use local plants as food resources and the potential to promote food diversity and agricultural resilience. We discuss how use of local plants and the practice of local agriculture can contribute to ongoing adaptability in times of global change. Most food crops are now produced, transported, and consumed long distances from their homelands of origin. At the same time, research and practices are directed primarily at improving the productivity of a small number of existing crops that form the cornerstone of a global food economy, rather than to increasing crop diversity. The result is a loss of agro-biodiversity, leading to a food industry that is more susceptible to abiotic and biotic stressors, and more at risk of catastrophic losses. Humans cultivate only about 150 of an estimated 30,000 edible plant species worldwide, with only 30 plant species comprising the vast majority of our diets. To some extent, these practices explain the food disparity among human populations, where nearly 1 billion people suffer insufficient nutrition and 2 billion people are obese or overweight. Commercial uses of new crops and wild plants of local origin have the potential to diversify global food production and better enable local adaptation to the diverse environments humans inhabit. We discuss the advantages, obstacles, and risks of using local plants. We also describe a case study—the missed opportunity to produce pine nuts commercially in the Western United States. We discuss the potential consequences of using local pine nuts rather than importing them overseas. Finally, we provide a list of edible native plants, and synthesize the state of research concerning the potential and challenges in using them for food production. The goal of our synthesis is to support more local food production using native plants in an ecologically sustainable manner

Lethal Parasites in Oysters from Coastal Georgia with Discussion of Disease and Management Implications

Extensive mortalities of oysters, Crassostrea virginica, occurred from 1985 through 1987 in coastal waters of Georgia. Fluid thioglycolate cultures of oysters collected from 16 of 17 locations revealed infections by the apicomplexan parasite Perkinsus marinus. An ascetosporan parasite, Haplosporidium nelsoni, was also observed in histopathological examination of oysters from 4 of the locations. While the range of H. nelsoni currently is recognized as the east coast of the United States from Maine to Florida, this is the first report of the parasite in Georgia waters. This paper documents the occurrence of these two lethal parasites in oysters from coastal waters of Georgia, along with potential disease and management implications. Results of an earlier independent and previously unpublished survey are also discussed which document the presence of P. marinus in Georgia as early as 1966