Structural Characteristics of Tree Cover and the Association with Cardiovascular and Respiratory Health in Tampa, FL.

Urban tree cover can provide several ecological and public health benefits. Secondary datasets for Tampa, FL, including sociodemographic variables (e.g., race/ethnicity), health data, and interpolated values for features of tree cover (e.g., percent canopy and leaf area index) were analyzed using correlation and regression. Percent canopy cover and leaf area index were inversely correlated to respiratory and cardiovascular outcomes, yet only leaf area index displayed a significant association with respiratory conditions in the logistic regression model. Percent racial/ethnic minority residents at the block group level was significantly negatively correlated with median income and tree density. Leaf area index was also significantly lower in block groups with more African-American residents. The percentage of African Americans (p = 0.101) and Hispanics (p < 0.001) were positively associated with respiratory outcomes while population density (p < 0.001), percent canopy (p < 0.01), and leaf area index (p < 0.01) were negatively associated. In multivariate models, higher tree density, leaf area index, and median income were significantly negatively associated with respiratory cases. Block groups with a higher proportion of African Americans had a higher odds of displaying respiratory admissions above the median rate. Tree density and median income were also negatively associated with cardiovascular cases. Home ownership and tree condition were significantly positively associated with cardiovascular cases.

Assessment of chlorophyll-a variations in high- and low-flow seasons in Apalachicola Bay by MODIS 250-m remote sensing.

Chlorophyll-a (chl-a) is considered as a primary indicator for water quality and foods for oyster growth in Apalachicola estuarine ecosystem. Assessment of chl-a concentration variation in response to river inflow is important for estuarine environmental research and management. In this study, remote sensing analysis has been conducted to evaluate the effects of river inflow on chlorophyll concentrations in Apalachicola Bay of Florida in the northeast Gulf of Mexico. A remote sensing model for chl-a was improved and applied to map spatial distributions of chl-a by using Moderate Resolution Imaging Spectroradiometer (MODIS) 250-m resolution imageries in high-flow and low-flow seasons in 2001 and 2008. Chl-a values approximately ranged from the minimum 6 µg/l to the maximum 29 µg/l in the study period. Maximum chl-a concentration in high-flow season was almost twice above that in low-flow season. The averaged mean and minimum chl-a level in the high-flow season were approximately 42 and 28 % higher than those in low-flow season, respectively. The remote sensing mapping of chl-a was able to show spatial variations of chl-a in the entire bay under different flow conditions, which indicated its advantage over the traditional field data sampling for monitoring water quality over a large area of estuary. The MODIS 250-m remote sensing regression model presented from this study can be used to support monitoring and assessment of the spatial chl-a distribution in the bay for environmental research and management in Apalachicola Bay.

Thiamethoxam soil contaminations reduce fertility of soil-dwelling beetles, Aethina tumida.

There in increasing evidence for recent global insect declines. This is of major concern as insects play a critical role in ecosystem functionality and human food security. Even though environmental pollutants are known to reduce insect fertility, their potential effects on insect fitness remain poorly understood - especially for soil-dwelling species. Here, we show that fertility of soil-dwelling beetles, Aethina tumida, is reduced, on average, by half due to field-realistic neonicotinoid soil contaminations. In the laboratory, pupating beetles were exposed via soil to concentrations of the neonicotinoid thiamethoxam that reflect global pollution of agricultural and natural habitats. Emerged adult phenotypes and reproduction were measured, and even the lowest concentration reported from natural habitats reduced subsequent reproduction by 50%. The data are most likely a conservative estimate as the beetles were only exposed during pupation. Since the tested concentrations reflect ubiquitous soil pollution, the data reveal a plausible mechanism for ongoing insect declines. An immediate reduction in environmental pollutants is urgently required if our aim is to mitigate the prevailing loss of species biodiversity.

Biosensors Show Promise as a Measure of Student Engagement in a Large Introductory Biology Course.

This study measured student engagement in real time through the use of skin biosensors, specifically galvanic skin response (GSR), in a large undergraduate lecture classroom. The study was conducted during an intervention in an introductory-level biology course (N = 420) in which one section of the course was taught with active-learning approaches and the other with traditional didactic teaching. GSR results were aligned and correlated with the Classroom Observation Protocol for Undergraduate STEM, or COPUS, and student self-reflections on their own engagement. Results showed that the active-learning section spent more time working in groups, resulting in GSR measures that trended higher and self-reported engagement, while showing indications of higher content learning gains compared with the traditional lecture section. Comparisons between COPUS scores and GSR readings indicate that engagement increased during group work and decreased during listening activities. Throughout a class period, GSR activity of the active-learning group showed increased trends compared with baseline measures, while the traditional lecture group showed decreased trends. Results indicate that GSR is a promising measure of real-time student engagement in the undergraduate classroom, bringing a new technique to discipline-based education researchers who aim to better measure student engagement; however, some limitations exist for broad-scale implementation.

Molecular cloning and biochemical characterization of a family-9 endoglucanase with an unusual structure from the gliding bacteria Cytophaga hutchinsonii.

Cytophaga hutchinsonii was originally isolated from sugarcane piles. This microorganism therefore probably produces an array of enzymes allowing it to digest cellulosic substrates. C. hutchinsonii thus represents a rich source of potentially effective cellulase enzymes that can be harnessed for conversion of biomass to simple sugars. These sugars can then be used as feedstock for ethanol production or other chemical syntheses. In this study, we report the PCR cloning of an endoglucanase gene (Cel9A) from C. hutchinsonii using degenerated primers directed at the catalytic domain. Alignment of the amino acids sequence revealed that Cel9A has a gene structure totally different from the other known cellulose degraders. The most striking feature of this cloned protein is the absence of a cellulose-binding domain (CBD), which to date was believed to be imperative in cellulose hydrolysis. Consequently, the Cel9A gene, encoding beta-1,4 endoglucanase from C. hutchinsonii was overexpressed in Escherichia coli with a His-Tag based expression vector. The resulting polypeptide, with a molecular mass of 105 KDa, was purified from cell extracts by affinity chromatography on cellulose. Mature Cel9A was optimally active at pH 5.0 and 45 degrees C. The enzyme efficiently hydrolyzes carboxymethyl- cellulose (CMC). Analysis of CMC and filter paper hydrolysis suggests that Cel9A is a nonprocessive enzyme with endo-cellulase activities.