The magnetic properties of plastically deformed steels.

This study concentrates on low carbon pearlitic steels. Two sets of experiments are carried out, the first on a section of semi-killed gas pipe and the second on specially prepared alloys of iron and carbon with pearlite fractions varying from 0.19% to 100%. Their magnetic properties are studied both in the as received state and after tensile plastic deformation. In addition, four different heat treatments are applied to the low carbon steel. Standard magnetisation and fluxmeter techniques are used to determine the bulk magnetic properties, with further use of a vibrating sample magnetometer for coercivity measurements. The Barkhausen noise of the samples is also recorded and High Voltage Lorentz Electron Microscopy used to directly observe the domain configurations and the interaction of the domain walls with dislocation tangles. The changes in the magnetic properties after tensile deformation are similar to those due to elastic compressive stress, with an additional increase in the coercivity. For the initial magnetisation curve initial permeability (J-Li) and maximum relative permeability both decrease, while the field at which the latter occurs (Hm) increases. The hysteresis curve shears over reducing the maximum differential permeability and the remanence and also increasing the coercivity. These results and the change in the shape of the hysteresis curve, most noticeable in the low carbon steels, are explained in terms of the reduction in easy domain wall movement due to the dislocation tangles, as observed under the electron microscope, and to the magnetostrictive effect of the compressive residual stress. Inter-relationships are found between coercivity and both J-Li and Hm. The coercivity io also found to vary linearly with both Vickers Hardness and Yield Stress. The Kneppo formula for the initial magnetisation curve is found to hold better for the higher carbon content steels with the fit deteriorating with increasing plastic deformation

Web-based Survey Tools

The World Wide Web provides an effective means of supporting survey projects, particularly when data collectors are geographically dispersed. Wireless and wireline communications can be used to integrate the survey team by providing current and consistent supporting materials to all members of the project team. Interactive tutorials, survey instructions and updates, technical support, computer-assisted survey instrument software and updates, text-based and graphic survey management reports, data views for monitoring and editing, and summary reports are some of the tools that can be delivered via Web browsers to data collection staff, survey managers, clients, and the public. We will describe Web-based tools that have been developed to support a national survey of natural resources, and discuss possible extensions of this work

Struggling with the Freshman Fifteen: College Students’ Recollections of Parents’ Memorable Messages about Weight

Considering the college years are considered a critical time in one’s life for changes in diet and exercise behavior and an increase in weight gain, this study explored the significant and impactful communication between college students and their parents during this transitional period. Using open-ended responses to an online questionnaire (N = 222), we explored the Memorable Messages (Knapp, Stohl, & Reardon, 1981) college students recall receiving from their parents about overweight and obesity. Students’ responses demonstrate that not only is weight a difficult topic to talk about, but it is also a difficult issue for people to manage on an individual basis. Students gave examples of messages and conversations referencing their own and their parents’ struggles with weight, and their responses illustrate the complex nature (i.e., emotions, interpretations of compliments versus criticism) of these important communication episodes

Going Remote: Marketing Library Resources and Services

Objectives • Describe the library’s efforts in restructuring marketing strategies strategies to reach out and engage library patrons in a virtual environment • Examine the impact of the efforts on library services and resource acces

Influence of hydroperiod on aquatic food-web structure and energy production in a floodplain wetland:implications for environmental flow management

Context: Environmental water is often used to manage floodplain wetlands that support many taxa, both terrestrial and aquatic. It is important to optimise the managed hydroperiod to maximise the provision of aquatically derived resources from wetlands. Aims: To test the hypothesis that increasing hydroperiod affects food-web structure and energy production in floodplain wetlands. Methods: Fatty acids and stable isotopes of δ13C and δ15N were used to define food-web structure, and estimate total energy production throughout a managed inundation event in a wetland in the northern Murray-Darling Basin. Key results: Food-web complexity increased with an increasing hydroperiod in line with predictable patterns of community assemblage development, before reducing sharply immediately prior to drying. Energy availability increased with an increasing hydroperiod and there was a strong correlation (ρ = 0.669, P = 0.0001) between energy availability and fatty acid concentration, which was in turn related to patterns of taxon occurrence. Conclusions and implications: Hydroperiod exerts a strong influence on aquatic invertebrate community trophic dynamics and energy provision. Planned flows should support maturation and stabilisation of the invertebrate community to optimise energy provision to consumers.</p

Functional Brain Hyperactivations Are Linked to an Electrophysiological Measure of Slow Interhemispheric Transfer Time after Pediatric Moderate/Severe Traumatic Brain Injury.

Increased task-related blood oxygen level dependent (BOLD) activation is commonly observed in functional magnetic resonance imaging (fMRI) studies of moderate/severe traumatic brain injury (msTBI), but the functional relevance of these hyperactivations and how they are linked to more direct measures of neuronal function remain largely unknown. Here, we investigated how working memory load (WML)-dependent BOLD activation was related to an electrophysiological measure of interhemispheric transfer time (IHTT) in a sample of 18 msTBI patients and 26 demographically matched controls from the UCLA RAPBI (Recovery after Pediatric Brain Injury) study. In the context of highly similar fMRI task performance, a subgroup of TBI patients with slow IHTT had greater BOLD activation with higher WML than both healthy control children and a subgroup of msTBI patients with normal IHTT. Slower IHTT treated as a continuous variable was also associated with BOLD hyperactivation in the full TBI sample and in controls. Higher WML-dependent BOLD activation was related to better performance on a clinical cognitive performance index, an association that was more pronounced within the patient group with slow IHTT. Our previous work has shown that a subgroup of children with slow IHTT after pediatric msTBI has increased risk for poor white matter organization, long-term neurodegeneration, and poor cognitive outcome. BOLD hyperactivations after msTBI may reflect neuronal compensatory processes supporting higher-order capacity demanding cognitive functions in the context of inefficient neuronal transfer of information. The link between BOLD hyperactivations and slow IHTT adds to the multi-modal validation of this electrophysiological measure as a promising biomarker

A review of the factors that influence pesticide residues in pollen and nectar: future research requirements for optimising the estimation of pollinator exposure

In recent years, the impact of Plant Protection Products (PPPs) on insect pollinator decline has stimulated significant amounts of research, as well as political and public interest. PPP residues have been found in various bee-related matrices, resulting in governmental bodies worldwide releasing guidance documents on methods for the assessment of the overall risk of PPPs to different bee species. An essential part of these risk assessments are PPP residues found in pollen and nectar, as they represent a key route of exposure. However, PPP residue values in these matrices exhibit large variations and are not available for many PPPs and crop species combinations, which results in inaccurate estimations and uncertainties in risk evaluation. Additionally, residue studies on pollen and nectar are expensive and practically challenging. An extrapolation between different cropping scenarios and PPPs is not yet justified, as the behaviour of PPPs in pollen and nectar is poorly understood. Therefore, this review aims to contribute to a better knowledge and understanding of the fate of PPP residues in pollen and nectar and to outline knowledge gaps and future research needs. The literature suggests that four primary factors, the crop type, the application method, the physicochemical properties of a compound and the environmental conditions have the greatest influence on PPP residues in pollen and nectar. However, these factors consist of many sub-factors and initial effects may be disguised by different sampling methodologies, impeding their exact characterisation. Moreover, knowledge about these factors is ambiguous and restricted to a few compounds and plant species. We propose that future research should concentrate on identifying relationships and common features amongst various PPP applications and crops, as well as an overall quantification of the described parameters; in order to enable a reliable estimation of PPP residues in pollen, nectar and other bee matrices