What Is Old Is New Again: Cooperative Extension\u27s Role in Democracy Building Through Civic Engagement

The early history of the Cooperative Extension Service is rich with examples of the agent\u27s role in building democracy among the citizenry of a young nation. However, the cold war shifted the focus of the public university toward the practice of one-way dissemination of research-based knowledge from the professor to the farmer and homemaker. As public funding continues to diminish for higher education, self-reflection suggests that Extension return to its original focus of building democracy through civic engagement. Suggestions for practice include valuing local knowledge and empowering citizens to solve their problems through action research projects

Impact of Communication Apprehension and Communication Skills Training on Interaction in a Distance Education Course

The importance of providing students with skills necessary for success in distance education classrooms is uncontested; however, few universities have done so. This case study sought to answer two questions: (a) What was the impact of communication apprehension (CA) on distance education students who experience the trait; and (b) What was the impact of a skills training session on interaction in a distance education course? Findings indicate that communication apprehensive students could not be motivated to interact regardless of interventions; however, non-CA students did benefit from the skills training session. An outline for a recommended skills training session based on recommendations from the literature and this study is included along with implications for educational practice

A Survey-Based Model for Collecting Stakeholder Input at a Land-Grant University

The 1998 Farm Bill (AREERA) called for greater engagement of land-grant universities with the public by mandating stakeholder input when setting priorities. The study described here developed a model for collecting and implementing input from stakeholders. The researchers collaborated with the Cooperative Extension Service (CES). Data was collected from a randomly selected group of producers. Findings include data regarding producers\u27 needs for services and preferred information sources. The model gives the CES a methodology for gathering input and stakeholders a voice at the program-planning table, increasing the likelihood that they will use research findings to improve practice

A Comparison of Farmers Who Do and Do Not Use Cooperative Extension Services

Land-grant universities have a historical role of serving Americans through the Cooperative Extension Service (CES); however, not all citizens are equally served by CES. Using a mailed survey, we identified a subpopulation of farmers who did not use CES and compared them to those who did. CES should develop communication systems that reach late adopters using their preferred modes of receiving information such as direct mailings. It is the responsibility of the CES to serve all stakeholders through the mandate of the Morrill Act

Uptake and Accumulation of Pharmaceuticals and Hormones in Vegetables after Irrigation with Reuse Water

The widespread occurrence of pharmaceutical and personal care products (PPCPs) and steroid hormones in watersheds has been recognized as an emerging environmental issue. The potential uptake and accumulation of these emerging contaminants by food plants that are irrigated with contaminated water could be a food safety issue. In the present project, uptake, translocation, accumulation, and depuration of seven PPCPs and three steroid hormones in lettuce and tomato plants were investigated using hydroponic cultures with compound concentrations of 0.5, 50, or 500 μg L-1 and several exposure scenarios. An isotopic dilution method was developed for the analysis of trace levels of PPCPs and hormones in food plants using liquid chromatography-tandem mass spectrometry (LC-MS/MS), combined with ultrasonication-shaking extraction and solid phase extraction (SPE) cleanup. For lettuce plants, all targeted PPCPs and hormones were detected in the roots. The bioaccumulation factors (BAFs) of PPCPs and hormones in lettuce roots were more than 1, indicating these emerging contaminants can be bound to or taken up by the plant roots. In lettuce leaves, only caffeine (CAF), carbamazepine (CBZ), and sulfamethoxazole (SMO) showed very high BAF values compared to other targeted PPCPs and hormones, indicating that these three compounds can easily translocate from lettuce roots to leaves and thereby accumulate in plant leaves. For tomato plants, all PPCPs and hormones were detected in the roots. By contrast, the translocation factor (TF) values of all targeted compounds except CAF and CBZ were very small in tomato plants, implying their poor translocation from roots to above-ground plant parts following uptake. The BAFs of all targeted hormones in tomato fruits were much less than 1, suggesting that hormone contamination of tomato fruits after irrigation with contaminated water could be negligible. In addition, exposure study showed that accumulation of PPCPs and hormones may rapidly reach a steady level (< 1 week) in lettuce plants with exposure through contaminated water. Lettuce plants also appear to have a potential to metabolize accumulated PPCPs, with the exception of triclosan (TCS) in roots and sulfamethoxazole (SMO) in leaves. Hormones did not exhibit any tendency to depurate. Comparing protective estimates of human exposure in lettuce leaves and acceptable daily intake (ADI) values suggests that CBZ and ethinylestradiol (EE2) could exceed their ADIs under some circumstances.Ope

Role of Oxygen Defects on the Magnetic Properties of Ultra-Small Sn\u3csub\u3e1−x\u3c/sub\u3eFe\u3csub\u3ex\u3c/sub\u3eO\u3csub\u3e2\u3c/sub\u3e Nanoparticles

Although the role of oxygen defects in the magnetism of metal oxide semiconductors has been widely discussed, it is been difficult to directly measure the oxygen defect concentration of samples to verify this. This work demonstrates a direct correlation between the photocatalytic activity of Sn1−xFexO2 nanoparticles and their magnetic properties. For this, a series of ~2.6 nm sized, well characterized, single-phase Sn1−xFexO2 crystallites with x = 0−0.20 were synthesized using tin acetate, urea, and appropriate amounts of iron acetate. X-ray photoelectron spectroscopy confirmed the concentration and 3+ oxidation state of the doped Fe ions. The maximum magnetic moment/Fe ion, μ, of 1.6 × 10−4 μB observed for the 0.1% Fe doped sample is smaller than the expected spin-only contribution from either high or low spin Fe3+ ions, and μ decreases with increasing Fe concentration. This behavior cannot be explained by the existing models of magnetic exchange. Photocatalytic studies of pure and Fe-doped SnO2 were used to understand the roles of doped Fe3+ ions and of the oxygen vacancies and defects. The photocatalytic rate constant k also showed an increase when SnO2 nanoparticles were doped with low concentrations of Fe3+, reaching a maximum at 0.1% Fe, followed by a rapid decrease of k for further increase in Fe%. Fe doping presumably increases the concentration of oxygen vacancies, and both Fe3+ ions and oxygen vacancies act as electron acceptors to reduce e−-h+ recombination and promote transfer of electrons (and/or holes) to the nanoparticle surface, where they participate in redox reactions. This electron transfer from the Fe3+ ions to local defect density of states at the nanoparticle surface could develop a magnetic moment at the surface states and leads to spontaneous ferromagnetic ordering of the surface shell under favorable conditions. However, at higher doping levels, the same Fe3+ ions might act as recombination centers causing a decrease of both k and magnetic moment μ

Unusual Crystallite Growth and Modification of Ferromagnetism Due to Aging in Pure and Doped Zno Nanoparticles

We report the unusual growth of pure and Fe-doped ZnO nanoparticles prepared by forced hydrolysis and the weakening of ferromagnetism due to aging in ambient conditions. More than four dozen nanoparticle samples in the size range of 4–20 nm were studied over 1 to 4 years. The as-prepared samples had significant changes in their crystallite sizes and magnetization as they aged in ambient conditions. Detailed studies using x ray diffraction and transmission electron microscopy (TEM) demonstrated that the crystallite size increased by as much as 1.4 times. Lattice parameters and strain also showed interesting changes. Magnetometry studies of Zn1−xFexO with x = 0–0.2 showed ferromagnetism at room temperature; however, keeping the samples in ambient conditions for one year resulted in modifications in the crystallite size and magnetization. For the Zn0.95Fe0.05O sample, the size changed from 7.9 nm to 9.0 nm, while the magnetization decreased from 1×10–3emu/g (memu/g) to 0.2 memu/g. Both magnetic and structural changes due to aging varied with the environment in which they were stored, indicating that these changes are related to the aging conditions

Dopant Spin States and Magnetism of Sn\u3csub\u3e1−x\u3c/sub\u3eFe\u3csub\u3ex\u3c/sub\u3eO\u3csub\u3e2\u3c/sub\u3e Nanoparticles

This work reports detailed investigations of a series of ∼2.6 nm sized, Sn1−xFexO2 crystallites with x = 0–0.10 using Mossbauer spectroscopy, x-ray photoelectron spectroscopy (XPS), electron paramagnetic resonance spectroscopy (EPR), and magnetometry to determine the oxidation state of Fe dopants and their role in the observed magnetic properties. The magnetic moment per Fe ion μ was the largest ∼6.48 × 10−3 μB for the sample with the lowest (0.001%) Fe doping, and it showed a rapid downward trend with increasing Fe doping. Majority of the Fe ions are in 3+ oxidation state occupying octahedral sites. Another significant fraction of Fe dopant ions is in 4+ oxidation state and a still smaller fraction might be existing as Fe2+ ions, both occupying distorted sites, presumably in the surface regions of the nanocrystals, near oxygen vacancies. These studies also suggest that the observed magnetism is not due to exchange coupling between Fe3+ spins. A more probable role for the multi-valent Fe ions may be to act as charge reservoirs, leading to charge transfer ferromagnetism

Resilience in moving water : effects of turbulence on the predatory impact of the lobate ctenophore Mnemiopsis leidyi

© The Author(s), 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Limnology and Oceanography 63 (2018): 445–458, doi:10.1002/lno.10642.Despite its delicate morphology, the lobate ctenophore Mnemiopsis leidyi thrives in coastal ecosystems as an influential zooplankton predator. Coastal ecosystems are often characterized as energetic systems with high levels of natural turbulence in the water column. To understand how natural wind-driven turbulence affects the feeding ecology of M. leidyi, we used a combination of approaches to quantify how naturally and laboratory generated turbulence affects the behavior, feeding processes and feeding impact of M. leidyi. Experiments using laboratory generated turbulence demonstrated that turbulence can reduce M. leidyi feeding rates on copepods and Artemia nauplii by > 50%. However, detailed feeding data from the field, collected during highly variable surface conditions, showed that wind-driven turbulence did not affect the feeding rates or prey selection of M. leidyi. Additional laboratory experiments and field observations suggest that the feeding process of M. leidyi is resilient to wind-driven turbulence because M. leidyi shows a behavioral response to turbulence by moving deeper in the water column. Seeking refuge in deeper waters enables M. leidyi to maintain high feeding rates even under high turbulence conditions generated by wind driven mixing. As a result, M. leidyi exerted a consistently high predatory impact on prey populations during highly variable and often energetic wind-driven mixing conditions. This resilience adds to our understanding of how M. leidyi can thrive in a wide spectrum of environments around the world. The limits to this resilience also set boundaries to its range expansion into novel areas.Seventh Framework Programme Grant Number: 600207; Division of Ocean Sciences Grant Number: 106118