606 research outputs found

    The Dynamics of Students' Behaviors and Reasoning during Collaborative Physics Tutorial Sessions

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    We investigate the dynamics of student behaviors (posture, gesture, vocal register, visual focus) and the substance of their reasoning during collaborative work on inquiry-based physics tutorials. Scherr has characterized student activity during tutorials as observable clusters of behaviors separated by sharp transitions, and has argued that these behavioral modes reflect students' epistemological framing of what they are doing, i.e., their sense of what is taking place with respect to knowledge. We analyze students' verbal reasoning during several tutorial sessions using the framework of Russ, and find a strong correlation between certain behavioral modes and the scientific quality of students' explanations. We suggest that this is due to a dynamic coupling of how students behave, how they frame an activity, and how they reason during that activity. This analysis supports the earlier claims of a dynamic between behavior and epistemology. We discuss implications for research and instruction.Comment: 4 pages, PERC 200

    Effect of Alga Bio 1.0 on Reducing Enteric Methane Emission from Cattle

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    An experiment was conducted to determine the effect of Alga Bio 1.0 inclusion on methane and carbon dioxide emissions along with diet digestibility. Three treatments were evaluated with 0, 69, and 103 grams per day Alga Bio 1.0 fed as a top dress in a corn-based diet. Indirect calorimetry headboxes were utilized to evaluate gas production with 12 cows in 4 replicated 3x3 Latin squares. There was a 39% reduction in methane per lb of dry matter intake for cattle fed 69 g of Alga Bio 1.0 and 63% reduction when cattle were fed 103 g of Alga Bio 1.0 daily compared to the control treatment. Both dry matter intake and organic matter intake were reduced by 13% with Alga Bio 1.0 inclusion, but the treatments did not affect the digestibility of dry matter or organic matter. Gross and digestible energy were not affected by Alga Bio 1.0 inclusion. Although this strain of algae is not FDA approved for feeding to cattle, the research shows great potential of Alga Bio 1.0 as a methane mitigation strategy

    In Situ Corrosion Studies on the Battleship USS Arizona

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    U.S. National Park Service Submerged Resources Center archaeologists and University of Nebraska-Lincoln metallurgists are assessing hull corrosion by drilling through accumulated concretions and measuring pH and corrosion potentials. Concretion samples are being analyzed to determine the role of microbes in the corrosion process, identify chemical species, and measure electrical and physical properties. The lowest values of pH and E corr occur at the metal/concretion interface. Analysis suggests a variable corrosion rate supported by hydrogen discharge and/or oxygen reduction inside the concretion

    Corrosion of Steel Shipwreck in the Marine Environment: USS \u3ci\u3eArizona\u3c/i\u3e—Part 1

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    The USS Arizona has remained submerged in Pearl Harbor, Hawaii, since the Japanese attack on December 7, 1941. The ship presents a potential hazard from fuel oil still present in the ship’s hull. As an important factor in management decisions, the effect of corrosion after nearly 65 years is being studied to determine the integrity of the ship’s structure. Coupon samples from the hull revealed decreasing corrosion rates from ~1 to 3 mpy (0.03 to 0.08 mm/y) from just below the water surface to the mudline. This is about one-third of that expected in the absence of biofouling or concretion. Methods of determining the corrosion rate, including correlation of chemistry and properties, are discussed

    Epirubicin With Cyclophosphamide Followed by Docetaxel With Trastuzumab and Bevacizumab as Neoadjuvant Therapy for HER2-Positive Locally Advanced Breast Cancer or as Adjuvant Therapy for HER2-Positive Pathologic Stage III Breast Cancer: A Phase II Trial of the NSABP Foundation Research Group, FB-5

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    Background The purpose of this study was to determine the cardiac safety and clinical activity of trastuzumab and bevacizumab with docetaxel after epirubicin with cyclophosphamide (EC) in patients with HER2-positive locally advanced breast cancer (LABC) or pathologic stage 3 breast cancer (PS3BC). Patients and Methods Patients received every 3 week treatment with 4 cycles of EC (90/600 mg/m2) followed by 4 cycles of docetaxel (100 mg/m2). Targeted therapy with standard-dose trastuzumab with bevacizumab 15 mg/kg was given for a total of 1 year. Coprimary end points were (1) rate of cardiac events (CEs) in all patients defined as clinical congestive heart failure with a significant decrease in left ventricular ejection fraction or cardiac deaths; and (2) pathologic complete response (pCR) in breast and nodes in the neoadjuvant cohort. An independent cardiac review panel determined whether criteria for a CE were met. Results A total of 105 patients were accrued, 76 with LABC treated with neoadjuvant therapy and 29 with PS3BC treated with adjuvant therapy. Median follow-up was 59.2 months. Among 99 evaluable patients for cardiac safety, 4 (4%; 95% confidence interval [CI], 1.1%-10.0%) met CE criteria. The pCR percentage in LABC patients was 46% (95% CI, 34%-59%). Five-year recurrence-free survival (RFS) and overall survival (OS) for all patients was 79.9% and 90.8%, respectively. Conclusion The regimen met predefined criteria for activity of interest with an acceptable rate of CEs. Although the pCR percentage was comparable with chemotherapy regimens with trastuzumab alone the high RFS and OS are of interest in these high-risk populations

    Clustering Attitudes and Behaviors of High/Low Involvement Grocery Shopper

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    The purpose of this exploratory and quantitative study was to examine the attitudes and behaviors of 14,807 grocery shop- pers. These respondents across the US were asked to answer attitudinal, behavioral, and demographic related questions. Shoppers were profiled by analyzing their responses to 16 relevant attitudinal and behavioral questions. A cluster analysis was performed followed by a discriminant analysis to deter- mine attitudinal and behavioral variables explaining cluster membership. A cross-tabulation analysis assessed demo- graphic variables that correlated with cluster membership. Two clusters were identified: high and low involvement grocery shoppers. In an event that has long been perceived as low involvement, a large percentage (53%) can be categorized as high involvement grocery shoppers. These shoppers tend to be younger. They were more likely to enjoy the hunt of finding products/deals, seek the advice of others and perceive that the products they buy reflect upon them. Grocery stores have a significant opportunity to target this high involvement shop- per. Grocery stores will need to create an integrative, engaging online and in-store experience to attract high involvement shoppers and ultimately increase store loyalty. The results of this research has significant communication, branding and digital marketing implications
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