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Articles 1 - 11 of 11
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Extension Workers As Orchestrators Of Civic Renewal Through Civic Professionalism, Nancy K. Franz
Extension Workers As Orchestrators Of Civic Renewal Through Civic Professionalism, Nancy K. Franz
Nancy K. Franz
I have a passion and a bias. I am passionate about the important role of the Cooperative Extension System (CES) in civic renewal. My bias is that extension workers (also known as agents or educators) are the key to civic renewal throughout the United States. No other institution has the same ability to reach all of America with education and organizing efforts. With extension workers in every county in the nation, this group of professionals and their work cut across age, race, ethnicity, religion, geography and many other demographic characteristics. Extension has a long history of being active in civic …
Yponomeuta Evonymellus Outbreaks In Southern Finland: Spatial Synchrony But Different Local Magnitudes, Brian J. Wilsey, Conchita Alonso, Timo Vuorisalo, Tuija Honkanen
Yponomeuta Evonymellus Outbreaks In Southern Finland: Spatial Synchrony But Different Local Magnitudes, Brian J. Wilsey, Conchita Alonso, Timo Vuorisalo, Tuija Honkanen
Brian J. Wilsey
Defoliations of Prunus padus by Yponomeuta evonymellus were monitored in two areas in southern Finland. During a long-term study (1980–1995) in the area with high peak defoliations, P. padus trees recorded two defoliation peaks, leading to complete defoliation of many trees. The negative relationship between pupal mass and current year tree defoliation during the peak years suggested shortage of food affected reproductive potential of Y. evonymellus. Furthermore, no delayed induced resistance was observed in these populations. Interannual correlations in degrees of defoliation experienced by individual trees were low, i.e. high defoliation in one year did not predict the degree of …
Avhrr Estimates Of Surface Temperature During The Southern Great Plains 1997 Experiment, Amy L. Kaleita, Praveen Kumar
Avhrr Estimates Of Surface Temperature During The Southern Great Plains 1997 Experiment, Amy L. Kaleita, Praveen Kumar
Amy L. Kaleita
In this study we aim to (1) explore the differences in the accuracy of satellitederived land-surface skin temperature for day and nighttime observations, (2) assess the effects of large solar zenith angles, and (3) develop an understanding of the spatial variability of the observed temperatures. Land-surface skin temperatures are obtained using the split-window technique from observations of the AVHRR instrument aboard the NOAA-12 and NOAA-14 satellites for the SGP97 (Southern Great Plains 1997) hydrology experiment. From the study of several days of observations we find that observed biases with respect to the ground temperature, both during day and night, are …
Countrysides Transformed, Pamela Riney-Kehrberg
Countrysides Transformed, Pamela Riney-Kehrberg
Pamela Riney-Kehrberg
Rural and agricultural history provide their readers different perspectives on the ways in which the countryside has changed over the course of American history. Rural history approaches the question of change from the perspective of communities and families, while agricultural history generally eschews the social perspective for issues of crop production. Such is the case of two recent and important books in rural and agricultural history, Hal Barron's Mixed Harvest: The Second Great Transformationin the Rural North, 1870-1930 and Steven Stoll's The Fruits of Natural Advantage: The Making of the Industrial Countryside in California. While both authors are intimately concerned …
A Buried Spruce Forest Provides Evidence At The Stand And Landscape Scale For The Effects Of Environment On Vegetation At The Pleistocene/Holocene Boundary, Douglas D. Stokke
A Buried Spruce Forest Provides Evidence At The Stand And Landscape Scale For The Effects Of Environment On Vegetation At The Pleistocene/Holocene Boundary, Douglas D. Stokke
Douglas D. Stokke
Due to a unique set of circumstances, we were able to excavate an entire spruce (Picea) forest in Michigan's Upper Peninsula, USA, which was buried in the early Holocene (9928 ± 133 uncalibrated 14C years bp). Trees ranged from < 5 cm to > 50 cm in diameter, and dominants were approximately 9 m tall. The stand was multi-aged, with a maximum tree age of 145 years. Well-preserved stem cross-sections (n = 140) were recovered and the entire stand was mapped. Stand reconstruction combined with pollen and sediment analysis revealed a pure spruce forest in the sandy lowlands surrounded by hills dominated by pine, oak …
Endocrine Responses To Chronic Androstenedione Intake In 30- To 56-Year-Old Men, Gregory A. Brown, Matthew D. Vukovich, Emily R. Martini, Marian L. Kohut, Warren D. Franke, David A. Jackson, Douglas S. King
Endocrine Responses To Chronic Androstenedione Intake In 30- To 56-Year-Old Men, Gregory A. Brown, Matthew D. Vukovich, Emily R. Martini, Marian L. Kohut, Warren D. Franke, David A. Jackson, Douglas S. King
Warren D Franke
In young men, chronic ingestion of 100 mg androstenedione (ASD), three times per day, does not increase serum total testosterone but does increase serum estrogen and ASD concentrations. We investigated the effects of ASD ingestion in healthy 30- to 56-yr-old men. In a double-blind, randomly assigned manner, subjects consumed 100 mg ASD three times daily (n 5 28), or placebo (n 5 27) for 28 days. Serum ASD , dihydrotestosterone (DHT), free and total testosterone, estradiol, prostate-specific antigen (PSA), and lipid concentrations were measured at week 0 and each week throughout the supplementation period. Serum total testosterone and PSA concentrations …
High-Pressure Effects On Lysosome Integrity And Lysosomal Enzyme Activity In Bovine Muscle, Stéphanie Jung, Marie De Lamballerie-Anton, Richard G. Taylor, Mohamed Ghoul
High-Pressure Effects On Lysosome Integrity And Lysosomal Enzyme Activity In Bovine Muscle, Stéphanie Jung, Marie De Lamballerie-Anton, Richard G. Taylor, Mohamed Ghoul
Stéphanie Jung
This study was conducted to determine whether the application of high hydrostatic pressure could modify the enzymatic activity and membrane integrity of lysosomes in muscle. Several combinations of pressure (0-600 MPa) and time (0-300 s) were applied to two types of samples: purified enzymes (cathepsin D and acid phosphatase) in buffer solution and intact muscle (biceps femoris). The enzymes studied showed varying degrees of susceptibility depending on the level of pressure, holding time, and environment. Acid phosphatase activity was minimally affected by pressure in buffer solution, whereas cathepsin D was modulated significantly by the pressure and time applied. The activities …
Biodiversity And Ecosystem Functioning: Importance Of Species Evenness In An Old Field, Brian J. Wilsey, Catherine Potvin
Biodiversity And Ecosystem Functioning: Importance Of Species Evenness In An Old Field, Brian J. Wilsey, Catherine Potvin
Brian J. Wilsey
Changes in land use, habitat fragmentation, nutrient enrichment, and environmental stress often lead to reduced plant diversity in ecosystems. However, it remains controversial whether these reductions in diversity will affect energy flow and nutrient cycling. Diversity has two components: species richness, or the number of plant species in a given area, and species evenness, or how well distributed abundance or biomass is among species within a community. We experimentally varied species evenness and the identity of the dominant plant species in an old field of Quebec to test whether plant productivity would increase with increasing levels of evenness, and whether …
Effects Of Resource Availability On Carbon Allocation And Developmental Instability In Cloned Birch Seedlings, Brian J. Wilsey, Janne H. Lappalainen, Jocelyn Martel, Kyösti Lempa, Vladimir Ossipov
Effects Of Resource Availability On Carbon Allocation And Developmental Instability In Cloned Birch Seedlings, Brian J. Wilsey, Janne H. Lappalainen, Jocelyn Martel, Kyösti Lempa, Vladimir Ossipov
Brian J. Wilsey
Abundant nitrogen improves seedling growth and establishment. Vigorous growth brings about changes in rates and patterns of plant development and changes in the relationship between primary and secondary metabolism, which may make seedlings more susceptible to herbivores and pathogens than are slow-growing seedlings. We studied how nitrogen fertilization and manual defoliation of source leaves affect growth, carbon allocation, and developmental instability in cloned seedlings of white birch (Betula pubescens Ehrh.). Biomass was higher, whereas concentrations of most classes of phenolic compounds were lower in the nitrogen-rich environment. Interestingly, fertilization did not change the concentrations of cell wall–bound proanthocyanidins, which represent …
A Computationally Based Identification Algorithm For Estrogen Receptor Ligands: Part 2. Evaluation Of A Herα Binding Affinity Model, Steven P. Bradbury, O. G. Mekenyan, V. Kamenska, P. K. Schmieder, G. T. Ankley
A Computationally Based Identification Algorithm For Estrogen Receptor Ligands: Part 2. Evaluation Of A Herα Binding Affinity Model, Steven P. Bradbury, O. G. Mekenyan, V. Kamenska, P. K. Schmieder, G. T. Ankley
Steven P. Bradbury
The objective of this study was to evaluate the capability of an expert system described in the previous paper (S. Bradbury et al., Toxicol. Sci. 58, 253–269) to identify the potential for chemicals to act as ligands of mammalian estrogen receptors (ERs). The basis of the expert system was a structure activity relationship (SAR) model, based on relative binding affinity (RBA) values for steroidal and nonsteroidal chemicals derived from human ERa (hERa) competitive binding assays. The expert system enables categorization of chemicals into (RBA ranges of < 0.1, 0.1 to 1, 1 to 10, 10 to 100, and >150% relative to 17b-estradiol. In the current analysis, the algorithm was evaluated with respect …
A Computationally Based Identification Algorithm For Estrogen Receptor Ligands: Part 1. Predicting Herα Binding Affinity, Steven P. Bradbury, V. Kamenska, P. Schmieder, G. Ankley, O. Mekenyan
A Computationally Based Identification Algorithm For Estrogen Receptor Ligands: Part 1. Predicting Herα Binding Affinity, Steven P. Bradbury, V. Kamenska, P. Schmieder, G. Ankley, O. Mekenyan
Steven P. Bradbury
The common reactivity pattern (COREPA) approach is a 3-dimensional, quantitative structure activity relationship (3-D QSAR) technique that permits identification and quantification of specific global and local stereoelectronic characteristics associated with a chemical’s biological activity. It goes beyond conventional 3-D QSAR approaches by incorporating dynamic chemical conformational flexibility in ligand-receptor interactions. The approach provides flexibility in screening chemical data sets in that it helps establish criteria for identifying false positives and false negatives, and is not dependent upon a predetermined and specified toxicophore or an alignment of conformers to a lead compound. The algorithm was recently used to screen chemical data …