Dietary Long-Chain Omega-3 Fatty Acids Are Related to Impulse Control and Anterior Cingulate Function in Adolescents

Impulse control, an emergent function modulated by the prefrontal cortex (PFC), helps to dampen risky behaviors during adolescence. Influences on PFC maturation during this period may contribute to variations in impulse control. Availability of omega-3 fatty acids, an essential dietary nutrient integral to neuronal structure and function, may be one such influence. This study examined whether intake of energy-adjusted long-chain omega-3 fatty acids [eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA)] was related to variation in impulse control and PFC activity during performance of an inhibitory task in adolescents (n = 87; 51.7% female, mean age 13.3 ± 1.1 years) enrolled in a longitudinal neuroimaging study. Intake of DHA + EPA was assessed using a food frequency questionnaire and adjusted for total energy intake. Inhibitory control was assessed using caregiver rating scale (BRIEF Inhibit subscale) and task performance (false alarm rate) on a Go/No-Go task performed during functional MRI. Reported intake of long-chain omega-3 was positively associated with caregiver ratings of adolescent ability to control impulses (p = 0.017) and there was a trend for an association between intake and task-based impulse control (p = 0.072). Furthermore, a regression of BOLD response within PFC during successful impulse control (Correct No-Go versus Incorrect No-Go) with energy-adjusted DHA + EPA intake revealed that adolescents reporting lower intakes display greater activation in the dorsal anterior cingulate, potentially suggestive of a possible lag in cortical development. The present results suggest that dietary omega-3 fatty acids are related to development of both impulse control and function of the dorsal anterior cingulate gyrus in normative adolescent development. Insufficiency of dietary omega-3 fatty acids during this developmental period may be a factor which hinders development of behavioral control

Estuary-associated syndrome in North Carolina: an occupational prevalence study.

Atlantic coast estuaries recently have experienced fish kills and fish with lesions attributed to Pfiesteria piscicida and related dinoflagellates. Human health effects have been reported from laboratory exposure and from a 1997 Maryland fish kill. North Carolina has recorded Pfiesteria-related fish kill events over the past decade, but human health effects from environmental exposure have not been systematically investigated or documented here. At the request of the state health agency, comprehensive examinations were conducted in a cross-sectional prevalence study of watermen working where Pfiesteria exposure may occur: waters where diseased or stressed fish were reported from June to September 1997, and where Pfiesteria had been identified in the past. Controls worked on unaffected waterways. The study was conducted 3 months after the last documented Pfiesteria-related fish kill. The goal was to document any persistent health effects from recent or remote contact with fish kills, fish with lesions, or affected waterways, using the 1997 U.S. Centers for Disease Control and Prevention case description for estuary-associated syndrome (EAS). Examinations included comprehensive medical, occupational, and environmental history, general medical, dermatologic, and neurologic examinations, vision testing, and neuropsychologic evaluations. Seventeen of 22 watermen working in affected waters and 11 of 21 in unaffected waters reported exposure to a fish kill or to fish with lesions. We found no pattern of abnormalities on medical, neurologic, neuropsychologic, or NES-2 evaluation. By history, one subject in each group met the EAS criteria, neither of whom had significant neuropsychological impairment when examined. Watermen from affected waterways had a significant reduction in visual contrast sensitivity (VCS) at the midspatial frequencies, but we did not identify a specific factor or exposure associated with this reduction. The cohorts did not differ in reported occupational exposure to solvents (qualitative) or to other neurotoxicants; however, exposure history was not sufficiently detailed to measure or control for solvent exposure. This small prevalence study in watermen, conducted 3 months after the last documented fish kill related to Pfiesteria, did not identify an increased risk of estuary-associated syndrome in those working on affected waterways. A significant difference between the estuary and ocean watermen was found on VCS, which could not be attributed to any specific factor or exposure. VCS may be affected by chemicals, drugs, alcohol, and several developmental and degenerative conditions; it has not been validated as being affected by known exposure to dinoflagellate secretions. VCS should be considered for inclusion in further studies, together with documentation or quantification of its potential confounders, to assess whether it has utility in relationship to dinoflagellate exposure

Alternative underground ore transport systems for the Jaguar Base metal deposit

Jabiru Metals completed a feasibility study on the Jaguar Base Metal Project in July 2005. The study was based on conventional truck haulage via a decline. Conveyor haulage was considered but not in sufficient detail to provide a meaningful comparison. The current study investigates the cost and productivity of alternative ore transport systems for the Jaguar project. The options considered are conventional underground truck, conveyor, road train, rigid frame truck, monorail haulage and shaft hoisting. Shaft hoisting was not considered in detail due to the high capital outlay for such a relatively short mine life of less than six years. This study goes beyond the common approach of evaluating haulage systems in isolation; it includes development costs, timing of ore production and costs associated with mine services as well as administration and milling costs. The results of this study indicate that the best haulage option for the Jaguar project is conventional truck using the Hitachi AH400 trucks. The net present value (NPV) for this option is A$8.13 million higher than the next best option namely the Kiruna E635 electric truck. The conveyor option has the lowest operating cost per tonne of ore but the longer development time negatively impacts on its NPV. The monorail option is considered impractical due to the number and length of trains required to achieve production targets.W P Darcey, E K Chanda and M D Kuruppuhttp://www.ausimm.com.au/undergroundoperators2011

Application of electro-monorail mine haulage systems in underground decline development

This study compares the electrical monorail transport system (EMTS) with the conventional truck haulage system in decline development. The study examines decline geometry, cycle times and cost and productivity in relation to the two haulage systems. Results show that productivity of the monorail is affected by loader cycle time to fill the monorail containers. Hence, to increase the productivity of the monorail a continuous loading system has been proposed in this paper. The operating costs of the monorail were found to be the same as the truck haulage system. However, if the cost of electricity is lower than 30¢ (Australian) per kilowatt hour, the operating cost for the monorail would be significantly lower than that of a comparable truck haulage system. The capital costs for the monorail are slightly higher than a comparable truck. However, the monorail’s lower operating costs plus environmental benefits make it more attractive than truck haulage

Developing a web-based system for coordinating school-based care for students with social, emotional, and behavioral problems

Many students with social, emotional, and behavioral problems receive school-based services. Multi-Tiered System of Support (MTSS) is the one most frequently referenced systems for coordinating services. The goal of this framework is to effectively match assessment and services to the needs of individual students. In many schools this process is limited by a lack of an overall coordinating system. As a result, many students receive services for social, emotional and behavioral problems that are unlikely to be effective, are not guided by progress monitoring, and not adequately informed by current and historical data. The Beacon System is a web-based tool created to enhance the quality of service provision for students with social, emotional, and behavioral problems by supporting continuous progress monitoring, helping educators know what services are likely to be helpful for a particular student according to their age and presenting problems, and providing educators and school mental health professionals with information to help them implement both familiar and unfamiliar interventions. Additionally, the Beacon system will enhance educators’ abilities to coordinate with a student’s entire intervention team and allow for continuity as a child changes grades, teachers, or schools. Enhancing these parts of the overall process can improve educators’ efforts to achieve the goals of MTSS to provide effective interventions matched to the students’ needs. The purpose of this manuscript is to describe the iterative development process used to create Beacon and highlight specific examples of some of the methods. In addition, we will describe how feedback from stakeholders (e.g., teachers, school mental health professionals) was used to inform decisions about design. Finally, we will describe the final development steps taken prior to pilot implementation studies and our plans for additional data collection to inform continued development of Beacon. This includes the strategies being used to measure outcomes at multiple levels including assessing a variety of behaviors of the professionals in the schools as well as student outcomes. These data will inform continuous development work that will keep us moving toward our goal of enhancing the outcomes of students with social, emotional and behavioral problems