Changes in Diatom Biodiversity in Lake Sinclair, Baldwin County, Georgia, USA

The effects of increased water temperature on algal community composition were investigated in Lake Sinclair, Baldwin County, Georgia, USA. The lake received waste cooling water from a coal burning power plant. Discharges of recycled lake water were, on average, 15°C ± 1.5°C (and up to 23°C) warmer than typical ambient temperatures. Seasonal changes in algal composition were observed, and the warmer sample site had a greater diversity of diatom species year round independent of changes in temperature. Thermal pollution created a high percent dissimilarity between diatoms at the warmer site and the remainder of the lake. Species turnover observed in natural samples was not detected for the warmer site. Anthropogenic thermal pollution was implicated as the factor inducing changes in the natural algal community composition, which may impact other trophic levels and ultimately the overall ecology of Lake Sinclair.

Detection of <i>Stx</i>2 Gene of <i>Escherichia coli</i>and Elevated Levels of Fecal Bacteria in the Cattle Farming Regions of Lake Oconee

The presence of Total coliform, Eschericha coli and enterococci were enumerated in the cattle farming areas of the Oconee Watershed using colilertTM and enterolertTM IDEXX plates, respectively. Microbial Source Tracking (MST) using Bacteroidales molecular markers for ruminant (RuBac) and human (HuBac) specific bacterial groups were used to determine the source of the fecal pollution in the watershed. In the cattle farming regions of the watershed higher levels of fecal bacteria were detected compared to the levels of fecal bacteria at the forested and residential sites. MST indicated that the cattle farming regions (except DC2) of the lake was impacted by fecal pollution from a ruminant source such as cattle. In addition, qPCR for the tuf gene of E. coli and the Stx2 gene that is commonly found in enterohemorragic E. coli O157:H7 were used to evaluate the presence of these bacteria in the study area. E. coli O157:H7 (Stx2 gene) was detected only in the beef cattle regions of the watershed. The presences of E. coli and Stx2 gene in the Oconee Watershed represent a potential public health risk because Lake Oconee and its tributaries are used for recreational activities as well as crop irrigation.

The Application of BBCH Scale for Codification and Illustrations of the Floral Stages of Caribbean Fine Cacao Theobroma cacao L.

Cocoa （Theobroma cacao L.） is the major input into the chocolate manufacturing industry, particularly the fine or flavor of the indigenous variety Trinitario, which is the hybrid of Crillo and Forastero. One key problem encountered by researchers is the inability to differentiate the various phenological stages of the cocoa reproductive cycle and to assess or predict the yield. This study sets out to map the various stages of the reproductive biology of cacao and to develop a set of photographic illustrations that appropriately describe the floral biology and development stages of Caribbean free cocoa as a tool for agronomist and farmers. It used a modified version of the codification of the ＂extended BBCH＂ scale （Biologische Bundesantalt, Bundessortenamt and Chemische Industrie, Germany）, which is a numerical system that differentiates between principal, secondary and tertiary growth stages. The phases and all floral stages to fruit development are described and illustrated in a set of photographs, which can now be used for training and referencing purposes. This is the first attempt to undertake and document this study.

Development of ZnTe film with high copper doping efficiency for solar cells

Since a hole barrier was formed in back contact due to mismatch of work function, the back contact material for CdTe cell has been a significant research direction. The ZnTe:Cu is an ideal back contact material, which reduces the valence band discontinuity and can be used as the electron back reflection layer to inhibit interface recombination. The conductivity of ZnTe:Cu film is improved by applying RF-coupled DC sputtering and post-deposition heat treatment. The doping efficiency is computed as the ratio of free hole density and copper concentration, which can be correlated with performance for CdTe-based solar cell. The higher doping efficiency means that more copper atoms substitute for Zn sites in ZnTe lattices and less mobilized copper atoms remain which can enter into the CdTe absorber layer. Copper atoms are suspected as dominant element for CdTe-based cell degradation. After optimizing the ZnTe:Cu films, a systematic study is carried out to incorporate ZnTe:Cu film into CdTe solar cell. The EQE spectrum is kept relatively stable over the long wavelength range without decreasing. It is proved that the conduction band barrier of device with ZnTe:Cu/Au contact material has an effect on the EQE response, which works as free electron barrier and reduces the recombination rate of free carrier. According to the dark J-V data or the light J-V data in the linear region, the current indicates that the intercept gives the diode reverse saturation current. The results of ideality factor indicate that the dominant recombination occurs in the space charge region. In addition, the space charge density and depletion width of solar cell can be estimated by C-V profiling.

Changes in Epipelic Diatom Diversity from the Savannah River Estuary

Littoral zones can be characterized with temporal exposure of algae to diurnal desiccation at low tides. Combinations of diverse freshwater, marine, and brackish diatoms dominate exposed mud samples. With enlargement of the delta of the Savannah River, Georgia and other anthropogenic influences, changes in the rich epipelic community will not be estimated accurately without baseline data. In the current study, mud samples were taken from the Savannah River estuary along with physicochemical characteristics every two months throughout 2011. Live algal communities were assessed in every sample and live to dead diatom proportions in the communities were calculated. Cleaned diatoms were analyzed following standard protocols. Community indices were compared between sampling events and with literature reports from similar habitats in the Southeastern USA diverse diatom community of 241 species was documented and 39 of those species should be described as new to science. Decrease in species richness and diversity was due to dominance of representatives of the genera Cymatosira and Minidiscus during the summer months.

The Failure of the Cross Correlation Measurement Technique

The experiment involves creating a sound wave that propagates down a pipe with 8 transducers attached at equally spaced intervals of 0.01016 m. The numerical method—the Cross Correlation Method, used to solve for the phase component, creates a high correlation value, but the speed of sound varies immensely. The method involves a Fast Fourier Transform (FFT) of the collected data, which is used to find the phase of the sound wave, and the slope of the position versus time graph, which is used to calculate the speed of sound. This high correlation value shows that the data are correct, but the numerical method for analyzing the data is incorrect.

Corporate Financial Policies under Heterogeneous Beliefs

This study investigates a firm's financing,investment,and payout policies through a rational expectation equilibrium based on which managers and outside investors have heterogeneous prior beliefs.The proposed model demonstrates that managers tend to overinvest(underinvest)if the extent of heterogeneousness is above(below)a threshold,which differs under distinct circumstances.Moreover,a price bubble is positively related to overinvestment,and the model shows that a firm's optimal financing choices and payout policies vary with the assumption of heterogeneous beliefs.