Kentucky, as with many regions around the globe, has a relatively long growing season with significant rainfall that could produce sizeable quantities of perennial herbaceous and woody biomass on land that does not compete with food crops. Additionally, there are limited options for renewable power production from low carbon sources such as solarphotovoltaic, wind and hydroelectric. Recent studies have shown that producing renewable energy from perennial cellulosic crops, as opposed to starch-based biofuel crops, will have a carbon-mitigating outcome. Currently, there is a lack of data regarding regionally suitable genotypes. Herein, we establish baseline values for multiple entry selections of three native C4 grass species, switchgrass (SW) (Panicum virgatum L.), eastern gamagrass (EG) (Trispicum dactyloides L.) and big bluestem (BB) (Andropogon gerardii Vitman). Yield potential examined over 7 years showed that environment, species and entries had a significant impact on yield, but EG had higher total yield over the duration of the study. Cellulosic biofuel potential was examined by measurement of saccharification efficiency, relative lignocellulosic energy density, cellulose content and lignin content during three growing seasons. EG had significantly higher digestibility rate than SW and BB. Underlying this was a negative correlation between lignification and saccharification efficiency. However, higher lignin content and higher cellulose content among SW entries resulted in higher energy density relative to EG and BB. These data reveal that locally bred EG varieties were most suited to cellulosic ethanol production under the growing conditions of central Kentucky, USA, compared with SW and BB and suggest the importance of regional examination. Nomenclature:NREL 5 national renewable energy laboratory FPU 5 filter paper unit DF 5 degrees of freedom EG 5 eastern gamagrass SW 5 switchgrass BB 5 big bluestem ANOVA 5 analysis of variance

The Brookings Institute analysis rate both Lexington and Louisville, Kentucky (USA) as two of the nation's largest carbon emitters. This high carbon footprint is largely due to the fact that 95% of electricity is produced from coal. Kentucky has limited options for electric power production from low carbon sources such as solar, wind, geothermal, and hydroelectric. Other states (TN, IN, OH, WV, and IL) in this region are similarly limited in renewable energy capacity. Bioenergy agriculture could account for a proportion of renewable energy needs, but to what extent is unclear. Herein, we found that abandoned agricultural land, not including land that is in fallow or crop rotation, aquatic ecosystems, nor plant-life that had passed through secondary ecological succession totaled 1.9 Mha and abandoned mine-land totaled 0.3 Mha, which combined accounted for 21% of Kentucky's land mass. A life cycle assessment was performed based on local yield and agronomic data for native grass bioenergy agriculture. These data showed that utilizing Kentucky's marginal land to grow native C 4 grasses for cellulosic ethanol and bioelectricity may account for up to 13.3% and 17.2% of the states 2 trillion MJ energy consumption and reduce green house gas emissions by 68% relative to gasoline.

Three children whose eardrums appeared normal upon previous examinations, one with the otomicroscope, apparently developed tympanic membrane cholesteatomas that penetrated the fibrous layer of the pars tensa. Their histories all included episodes of acute otitis media, but no otorrhea. No otologic surgical procedures, including myringotomy, had been performed. These cases are thought to provide clinical support for the basal epithelial migration theory of cholesteatoma genesis. Rüedi's experiments suggest that cholesteatomas resulting from basal epithelial migration may not be visible for 18 to 30 days; thus, follow-up evaluations after acute otitis media should probably include examinations one and two months after the infection. Pediatricians and family physicians should be urged to seek otologic consultation for patients with even minor eardrum abnormalities, particularly those following infection.

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