Implementing constructivism in the middle school classroom

This study defines the components of a middle school history curriculum based on a theory of learning consistent with the use of cognitive tools and the tenets of constructivism. Utilizing a comparative analysis of learning theories encompassing developmental and constructivist beliefs and their influence on appropriate instructional design, the research addresses the necessary pairing of instructional planning and learning theory. Additionally, an examination of linguistic tools and their relationship to cultural development and distinctive kinds of comprehension, as well as specifics of the various learning stages, preferences, and skills are used to provide a rationale. This analysis is employed in the development of a middle school history/social studies curriculum premised upon the ideology that students employ intellectual tools at different stages of maturation that support specific types of understanding. The resulting instructional design for students, grade six through eight, contains the fundamental elements of constructivism, how these elements manifest themselves in a curriculum, appropriate activities, projects, and methods for evaluation. The study concludes in a discussion concerning the implications of coupling constructivist theory with linguistic strengths, and the impact this union has on curriculum design

Nutrition of Floricultural Crops: How Far Have We Come?

According to Seeley (1979), even though the Society for Horticultural Science was formed in 1903, it wasn\u27t until the 1930s that research papers on the subject of floriculture were published in our journal. There were, however, numerous college and university bulletins about floricultural crops which included fertilizer studies (for example, Blake, 1915). Despite the sluggish start, in the last 25 years, in the American Society of Horticultural Science\u27s three journals (Journal of the American Society for Horticultural Science, HortScience, and HortTechnology) alone, there have been over 240 publications relating to the nutrition of floricultural crops. Journal such as Scientia Horticulturae, Journal of Plant Nutrition, Agrochemica, Journal of Environmental Horticulture as well as others also publish papers on this topic.Thus, the focus of this article will be on research published in ASHS journals. Even with this narrowed focus, only a sampling of the research that has occurred can be mentioned here. Floriculture in its broadest sense involves growth and development physiology, culture, management and postharvest physiology of cut flowers, potted flowering and foliage plants, cacti and carnivorous plants, bedding plants and herbaceous perennials including forbs and geophytes. Adequate elemental content of these plants is critical at all growth stages to ensure a marketable product

Annual Statice in Nebraska

Annual statice can be successfully grown, harvested, and preserved under Nebraska\u27s climatic conditions. Start plants from seed nine weeks before they are field or garden planted. The earlier in the season that planting occurs, the greater the yield. Apply fertilizer before and after planting. Herbicides are recommended to eliminate hand weeding and allow maximum yield. Flowers should be harvested when all florets are fully open and can be used fresh, or dry stored at 2C (36F). Statice can also be preserved by drying or soaking fresh cut stems in 1:2 or 1:3 glycerine to water solution for 48 hours and then microwaving for 1 minute at 34C (97F) (medium high setting)

Management and Modeling of Winter-time Basil Cultivars Grown with a Cap MAT System

Basil (Ocimum basilicum) is a high value crop, currently grown in the field and greenhouses in Nebraska. Winter-time, greenhouse studies were conducted during 2015 and 2016, focusing on cultivars of basil grown on a Cap MAT II® system with various levels of fertilizer application. The goal was to select high value cultivars that could be grown in Nebraska greenhouses. The studies used water content, electrical conductivity, photosynthetically active radiation (PAR), and relative humidity, air and soil media temperature sensors. Greenhouse systems can be very complex, even though controlled by mechanical heating and cooling. Uncertain or ambiguous environmental and plant growth factors can occur, where growers need to plan, adapt, and react appropriately. Plant harvest weights and electronic sensor data was recorded over time and used for training and internally validating fuzzy logic inference and classification models. Studies showed that GENFIS2 ‘subtractive clustering’ of data, prior to ANFIS training, resulted in good correlations for predicted growth (R2 \u3e 0.85), with small numbers of effective rules and membership functions. Cross-validation and internal validation studies also showed good correlations (R2 \u3e 0.85). Decisions on basil cultivar selection and forecasting as to how quickly a basil crop will reach marketable size will help growers to know when to harvest, for optimal yield and predictable quantity of essential oils. If one can predict reliably how much essential oil will be produced, then the methods and resultant products can be proposed for USP or FDA approval. Currently, most plant medicinal and herbal oils and other supplements vary too widely in composition for approval. The use of fuzzy set theory could be a useful mathematical tool for plant and horticultural production studies

Dynamic Classification of Moisture Stress Using Canopy and Leaf Temperature Responses to a Step Changes of Incident Radiation

Environmental conditions affect plant productivity and understanding how plants respond to drought stress can be measured in different ways. This study focused on measuring leaf response time to induced water stress. Leaf response time to a step increase and step decrease in radiation was computed for four species of well-watered and water-stressed plants in a controlled environment. The canopy temperature was measured with an infrared thermometer and a thermal imaging camera. Thermal images were analyzed to determine the average temperature of a selected single, unobstructed leaf at the top of the canopy. Both the canopy response time and the single leaf response time were computed for this study. The response times to a step change of radiation for well-watered plants were generally longer than the response times of water stressed plants. These results show that response time may be used as an indicator of plant water stress

Management and Modeling of Winter-time Basil Cultivars Grown with a Cap MAT System

Basil (Ocimum basilicum) is a high value crop, currently grown in the field and greenhouses in Nebraska. Winter-time, greenhouse studies were conducted during 2015 and 2016, focusing on cultivars of basil grown on a Cap MAT II® system with various levels of fertilizer application. The goal was to select high value cultivars that could be grown in Nebraska greenhouses. The studies used water content, electrical conductivity, photosynthetically active radiation (PAR), and relative humidity, air and soil media temperature sensors. Greenhouse systems can be very complex, even though controlled by mechanical heating and cooling. Uncertain or ambiguous environmental and plant growth factors can occur, where growers need to plan, adapt, and react appropriately. Plant harvest weights and electronic sensor data was recorded over time and used for training and internally validating fuzzy logic inference and classification models. Studies showed that GENFIS2 ‘subtractive clustering’ of data, prior to ANFIS training, resulted in good correlations for predicted growth (R2 \u3e 0.85), with small numbers of effective rules and membership functions. Cross-validation and internal validation studies also showed good correlations (R2 \u3e 0.85). Decisions on basil cultivar selection and forecasting as to how quickly a basil crop will reach marketable size will help growers to know when to harvest, for optimal yield and predictable quantity of essential oils. If one can predict reliably how much essential oil will be produced, then the methods and resultant products can be proposed for USP or FDA approval. Currently, most plant medicinal and herbal oils and other supplements vary too widely in composition for approval. The use of fuzzy set theory could be a useful mathematical tool for plant and horticultural production studies

Incorporating Chokeberry (Aronia) into a Home Landscape

Chokeberry (Aronia) is an ornamental plant that has found use in the home landscape, providing colorful displays and annually producing berries for the enjoyment of the homeowner and wildlife alike. With careful placement, this durable plant needs minimal care and has few pest problems. It is gaining attention for its timeless beauty

Dynamic Classification of Moisture Stress Using Canopy and Leaf Temperature Responses to a Step Changes of Incident Radiation

Environmental conditions affect plant productivity and understanding how plants respond to drought stress can be measured in different ways. This study focused on measuring leaf response time to induced water stress. Leaf response time to a step increase and step decrease in radiation was computed for four species of well-watered and water-stressed plants in a controlled environment. The canopy temperature was measured with an infrared thermometer and a thermal imaging camera. Thermal images were analyzed to determine the average temperature of a selected single, unobstructed leaf at the top of the canopy. Both the canopy response time and the single leaf response time were computed for this study. The response times to a step change of radiation for well-watered plants were generally longer than the response times of water stressed plants. These results show that response time may be used as an indicator of plant water stress

AFTER FURTHER REVIEW: AN UPDATE ON MODELING AND DESIGN STRATEGIES FOR AGRICULTURAL DOSE-RESPONSE EXPERIMENTS

Research investigating dose-response relationships is common in agricultural science. This paper is an expansion on previous work by Guo, et al. (2006) motivated by plant nutrition research in horticulture. Plant response to level of nutrient applied is typically sigmoidal, i.e. no response at very low levels, observable response at mid-levels, point-of-diminishing returns and plateau at high levels. Plant scientists need accurate estimates of these response relationships for many reasons, including determining the lower threshold below which plants show deficiency symptoms and the point of diminishing returns, above which excessive doses are economically and environmentally costly. Guo et al. presented models and designs that address these requirements and a simulation study to assess and compare the small-sample behavior of these models and designs. This paper expands on that simulation study. In addition, a simulation study based procedure for exploring designs for experimental scenarios fitting this description is presented. This simulation study approach utilizes simulation based fit statistics in conjunction with various lack-of-fit plots to produce a design robust to multiple candidate models

A COMPARISON OF MODELS AND DESIGNS FOR EXPERIMENTS WITH NONLINEAR DOSE-RESPONSE RELATIONSHIPS

Research investigating dose-response relationship is common in agricultural science. Animal response to drug dose and plant response to amount of irrigation, pesticide, or fertilizer are familiar examples. This paper is motivated by plant nutrition research in horticulture. Plant response to level of nutrient applied is typically sigmoidal, i.e. no response at very low levels, observable response at mid-levels, point-of-diminishing returns and plateau at high levels. Plant scientists need accurate estimates of these response relationships 1) to determine lower threshold below which plants show deficiency symptoms and 2) to determine upper point-of-diminishing returns, above which excessive doses are economically and environmentally costly. Landes, at al. (1999 and Olson et al. (2001) did initial work identifying potentially useful models. Paparozzi, et al. (2005) investigated dose (micro- and macro-nutrient) response (elemental leaf and stem concentration) relationships in Poinsettia. They found that 1) nutrients must be considered as a system, hence multifactor experiments are essential, 2) resources are limited, meaning that experiments must use response-surface principles, and 3) nutrient-response relationships are rarely modeled adequately by 2nd order polynomial regression models, so standard response surface methods are inadequate. This paper presents models and designs that address these requirements and a simulation study to assess and compare the small-sample behavior of these models and designs