Tackling Teaching: Understanding Commonalities among Chemistry, Mathematics, and Physics Classroom Practices.

Abstract: Education research in chemistry, mathematics, and physics tends to focus on issues inherent to the discipline, most notably content. At this time, little literature evidence exists that documents fruitful collaborations between education specialists across the STEM disciplines. This work seeks to unite the disciplines by investigating a common task: teaching. This study explores how discipline-specific practices influence the common act of reformed teaching pedagogy with a focus on the use of inquiry. We seek to identify commonalities among classroom teaching practices in these disciplines and contribute to the development of analytical tools to study STEM teaching

Investigating episodic-memory predictors of early-stage Alzheimer’s disease

A rapid increase in Alzheimer’s disease (AD) patients is expected over the next 30 years. Accordingly, there is a critical need for early-stage AD detection methods that can enable professionals to treat the disease adequately. The present study considers the ability of episodic-memory measures to predict mild cognitive impairment (MCI) to AD conversion and thus, detect early-stage AD. Using a binary logistic regression, episodic-memory tests were compared to each other and to prominent neuroimaging methods in MCI converter (MCI participants who developed AD) and MCI non-converter groups (MCI participants who did not develop AD). Standard tests for AD (e.g., MMSE) were also compared to specific episodic-memory tests—using a principal component analysis—to test if standard tests can measure episodic memory. Our study acquired all data from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) and tested participants over four years. Our results indicate that individual episodic-memory measures could predict MCI to AD conversion better than episodic memory, neuroimaging, and mixed models. We theorised that mixed models were worse than individual tests, as mixed episodic-memory models increase multicollinearity and neuroimaging measures had poor accuracy. Specifically, the most accurate predictors were the ADNI memory score in year one (56.4%), the RAVLT percent forgetting measure in year two (71.7%), and the logical memory test in years three (76.9%) and four (77.2%). Our results also indicated that standard tests could be used to measure episodic memory. In conclusion, our study highlighted the ability of episodic-memory tests to predict disease conversion and thus detect early-stage AD

Estimating Evolutionary Volatility in a Maximum-Likelihood Framework

Evolutionary volatility is a trait that encompasses a clade’s combined capacity for origination and extinction. High volatility increases extinction risk, and declining global extinction rates are thought to be linked to declining volatility. Despite volatility’s scientific importance, there is no standardized way of measuring it. This study provides a new method, derived from a stochastic birth-death model, of estimating evolutionary volatility from fossil data. Simulations indicate that the method produces accurate and precise estimates for large fossil datasets. Analysis of fossil data for five bivalve families (Lucinidae, Mytilidae, Pectinidae, Pholadomyidae, and Veneridae) indicates that diversity projections made from the estimates lack precision and do not capture important aspects of the data. However, this method of estimating volatility serves as a simple and computationally efficient null model for comparisons against more complex hypotheses

Hydroponic and Soilless Culture Systems and Transplant Practices Influence Production of Basil (Omicum basilicum L.)

Two controlled-environment greenhouse experiments evaluated (1) plant growth and morphology of basil (Omicum basilicum L.) grown in three different hydroponic and soilless substrate systems and (2) seedling tray cell-count and transplant date into hydroponic culture effects on basil growth and yield at harvest. For the first experiment, four basil cultivars (‘Genovese’, ‘Mrs. Burns Lemon’, ‘Sweet Thai’, and ‘Cinnamon’) were grown in deep flow technique (DFT) hydroponics, nutrient film technique (NFT) hydroponics, and a novel shallow aggregate ebb-and-flood (SAEF) soilless substrate system and were harvested after 21 d. Plant yield and morphological characteristics measured at harvest included shoot fresh mass, shoot dry mass, leaf SPAD chlorophyll content, total leaf area per plant, plant height, node number, and internode length. For the second experiment, seedlings of ‘Genovese’ basil were germinated in a soilless peat-based substrate and grown in trays with cell-counts of 32, 50, 72, 105, and 162 and corresponding root volumes of (in cm3) of 98.1, 50.2, 38.5, 19.6, and 16.3, respectively. Basil seedlings for each tray type were transplanted in NFT hydroponic systems at 14 d, 21 d, and 28 d after sowing seed. Plants were harvested from NFT systems 35 d after sowing seed, and collected data at harvest included shoot fresh mass, shoot dry mass, plant height, and substrate pH and electrical conductivity (EC). Plant growth and morphology of basil cultivars differed between hydroponic and soilless culture systems, and harvested yields were overall greater for basil produced in DFT hydroponics compared to NFT hydroponics and SAEF soilless substrate systems. Basil seedlings grown in low cell-count trays and transplanted at earlier dates into NFT systems had greater yields compared to basil grown in high cell-count trays and transplanted at later dates. The combination of growing seedlings in trays with low cell-counts and early transplant into hydroponics likely increased yield by reducing potential for root restriction, increasing nutrient and water availability per plant, and increasing individual plant spacing for greater accumulation of photosynthetic light

Energy cost of horizontal walking cattle and horses of various ages and body weights.

Publication authorized May 17, 1934."Taken in part from a thesis by W.C. Hall"--P. [3].Digitized 2007 AES.Includes bibliographical references (page 16)

Energy increment of standing over lying and the cost of getting up and lying down in growing ruminants (cattle and sheep) : comparison of pulse rate, respiration rate, tidal air, and minute volume of pulmonary ventilation during lying and standing.

Publication authorized November 22, 1932."This bulletin contains parts of the data included in a dissertation by Warren C. Hall"--P. [5].Digitized 2007 AES.Includes bibliographical references (page 23)