The Deglaciation of Maine, USA

The glacial geology of Maine records the northward recession of the Late Wisconsinan Laurentide Ice Sheet, followed by development of a residual ice cap in the Maine-Québec border region due to marine transgression of the St. Lawrence Lowland in Canada. The pattern of deglaciation across southern Maine has been reconstructed from numerous end moraines, deltas and submarine fans deposited during marine transgression of the coastal lowland. Inland from the marine limit, a less-detailed sequence of deglaciation is recorded by striation patterns, meltwater channels, scattered moraines and waterlain deposits that constrain the trend of the ice margin. There is no evidence that the northern Maine ice cap extended as far south-west as the Boundary Mountains and New Hampshire border. Newly-obtained radiocarbon ages from marine and terrestrial ice-proximal environments have improved the chronology of glacial recession in Maine. Many of these ages were obtained by coring late-glacial sediments beneath ponds and lakes. Data from this study show that the state was deglaciated between about 14.5 and 11.0 ka BP (14C years). The coastal moraine belt in southern Maine was deposited by oscillatory ice-margin retreat during the cold pre-Bølling time. Rapid ice recession to northern Maine then occurred between 13 and 11 ka BP, during the warmer Bølling/Allerød chronozones. Radiocarbon-dated pond sediments in western and northern Maine show lithologic evidence of Younger Dryas climatic cooling and persistence of the northern ice cap into Younger Dryas time. A large discrepancy still exists between radiocarbon ages of deglaciation in coastal south-western Maine and the timing of ice retreat indicated by New England varve records in areas to the west. Part of this problem may stem from the uncertainty of reservoir corrections applied to the radiocarbon ages of marine organics

One size does not fit all: advanced practice provider considerations for the antimicrobial steward

Advanced practice providers are a diverse and established group of antimicrobial prescribers in both ambulatory and inpatient settings. We outline important considerations for antimicrobial stewardship programs and stewards to consider when engaging this important group of providers

Exposure to Sublethal Doses of Fipronil and Thiacloprid Highly Increases Mortality of Honeybees Previously Infected by Nosema ceranae

International audienceBACKGROUND: The honeybee, Apis mellifera, is undergoing a worldwide decline whose origin is still in debate. Studies performed for twenty years suggest that this decline may involve both infectious diseases and exposure to pesticides. Joint action of pathogens and chemicals are known to threaten several organisms but the combined effects of these stressors were poorly investigated in honeybees. Our study was designed to explore the effect of Nosema ceranae infection on honeybee sensitivity to sublethal doses of the insecticides fipronil and thiacloprid. METHODOLOGY/FINDING: Five days after their emergence, honeybees were divided in 6 experimental groups: (i) uninfected controls, (ii) infected with N. ceranae, (iii) uninfected and exposed to fipronil, (iv) uninfected and exposed to thiacloprid, (v) infected with N. ceranae and exposed 10 days post-infection (p.i.) to fipronil, and (vi) infected with N. ceranae and exposed 10 days p.i. to thiacloprid. Honeybee mortality and insecticide consumption were analyzed daily and the intestinal spore content was evaluated 20 days after infection. A significant increase in honeybee mortality was observed when N. ceranae-infected honeybees were exposed to sublethal doses of insecticides. Surprisingly, exposures to fipronil and thiacloprid had opposite effects on microsporidian spore production. Analysis of the honeybee detoxification system 10 days p.i. showed that N. ceranae infection induced an increase in glutathione-S-transferase activity in midgut and fat body but not in 7-ethoxycoumarin-O-deethylase activity. CONCLUSIONS/SIGNIFICANCE: After exposure to sublethal doses of fipronil or thiacloprid a higher mortality was observed in N. ceranae-infected honeybees than in uninfected ones. The synergistic effect of N. ceranae and insecticide on honeybee mortality, however, did not appear strongly linked to a decrease of the insect detoxification system. These data support the hypothesis that the combination of the increasing prevalence of N. ceranae with high pesticide content in beehives may contribute to colony depopulation

Establishing a method to support academic and professional competence throughout an undergraduate radiography programme

Purpose: Radiography degree programmes are coming under increasing pressurefrom the community to ensure that graduates have not only the necessary academic developmentbut also the practice-based skills. This study aims to establish a method of monitoringstudents’ progress towards, and ability to meet, academic and professional competencesthroughout a radiography programme.Methods: Questionnaires were designed for students and academic staff to determine thestages and standards of progress of competence development, and to inform the review processof the current assessment tools throughout the programme. A literature search identifiedthe appropriate pedagogy as a basis for devising the method. Another questionnaire was distributedto overseas radiography institutions to gain insights into other assessment practicesto validate the framework.Results and discussion: It was established that years of study rather than semester periodswere appropriate to allow students to meet the standards. Discrepancies were noted in theexpectations between academic staff (higher expectations) and students (more realistic) interms of the pace of development expected. As students progress at different rates, and donot experience the same clinical exposure, their ability to meet expectations may differand so both sets of expectations were combined as a range of criteria. A multi-dimensionalassessment approach should be adequate to gauge students’ progress but time and resourceeffectiveness has not yet been addressed. The portfolio was identified as the pedagogy capableof integrating all the competence assessment tools, linked by reflective writing, to gatherindividual outcomes into a whole, and form a holistic framework.Outcome: The portfolio framework will initially run as a voluntary activity and standards ofprogress corresponding to the students’ stages will be delivered to participants in advance.Participants will be required to select materials and reflect on these, as evidence of development.Faculty members will provide support and feedback to students and oversee the wholeprocess

Ion gun generated electromagnetic interference on the SCATHA satellite.

http://archive.org/details/iongungeneratede00weddNAN