5,952 research outputs found

    Abundance of Insects Inhabiting the Male Strobili of Red Pine

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    (excerpt) Southwood (1973) concluded that pollen feeding was probably the first step in the development of the phytophagous habit in insects, because pollen, compared with plant foliage, is rich in nutrients and low in sewndary defense substances. Surprisingly, little is known about insects that feed mainly on pollen. For example, in a bibliography of insects that feed on reproductive structures of North American conifers (Barcia and Merkel, 1972), less than three per cent of 719 references pertained to pollen feeders. This note reports on the kinds and abundance of insects found inhabiting clusters of fresh staminate or male strobili (MS) of 60- to 65-year-old red pine trees in two seed production areas (SPAs) in northern Minnesota

    Interview with Karl Mattson, August 10, 2011

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    Karl Mattson was interviewed on August 10, 2011 by Michael Birkner about his life starting with his earliest memories. This interview is part 1 of a 2 part interview. Length of Interview: 46 minutes Collection Note: This oral history was selected from the Oral History Collection maintained by Special Collections & College Archives. Transcripts are available for browsing in the Special Collections Reading Room, 4th floor, Musselman Library. GettDigital contains the complete listing of oral histories done from 1978 to the present. To view this list and to access selected digital versions please visit -- http://gettysburg.cdmhost.com/cdm/landingpage/collection/p16274coll

    Degree-Day Summation and Hatching of the Forest Tent Caterpillar, \u3ci\u3eMalacosoma Disstria\u3c/i\u3e (Lepidoptera: Lasiocampidae)

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    (excerpt) The forest tent caterpillar, Malacosoma disstria (Htibner), is a common defoliater of deciduous trees throughout most of the United States and Canada. It is a well known outbreak species, whose populations erupt periodically (every 10 to 16 years) when forest conditions are suitable. Typical outbreaks last three to six years in a given geographic area and then collapse as quickly as they arise. This note documents the relation between forest tent caterpillar egg hatching in the field and heat accumulation (degree-days) leading up to hatch. This information will permit (a) predicting the date on which eggs will hatch by summing degree days during the insect\u27s overwintering period, and (b) comparing with populations in other years and areas. The data came from an outbreak in northern Minnesota that began near International Falls in 1966 and collapsed in 1972 (Witter et al., 1975)

    Learning Style Diversity in Post –Secondary Distance Education

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    During the fall semester of 2005, 153 university graduate students’ preferred learning styles were measured with the Kolb Learning Style Inventory, online version 3.1. The primary findings of the study indicated all of the learning styles and processes described by Kolb were represented in the distance learning population and suggested distance and residential learners uniquely engage the learning process. Biblical references were discussed with respect to the uniqueness displayed by study participants

    Use of Scanning Electron Microscopy to Study Structural-Functional Relationships in Normal and Diseased Platelets

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    This paper reviews the contribution of scanning electron microscopy (SEM) to our understanding of platelet physiology and pathology. Observations of platelet shape changes which accompany activation and the ability to visualize and analyze platelet aggregation and adhesion in three dimensions make this experimental medium an important tool in the evaluation of healthy and diseased platelets. While SEM adds a valuable third dimension to the study of morphology and ultrastructure, its greatest contribution is realized when studies are correlated directly with light and/or transmission electron microscopic observations and with studies of functional capacity
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