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Multiple phenotypic traits often interact with each other to determine an individual's fitness. Behavioral and extended phenotypic traits, such as architectural constructions, can contribute to fitness in an integrated way. The goal of this study was to understand how the interaction between behavioral and extended phenotypic traits can affect foraging success. We tested this question using black widow spiders, where spiders that are aggressive in a foraging context tend to build more gumfooted silk lines that aid in prey capture, while non-aggressive spiders build webs with fewer gumfooted lines. We repeatedly assessed behavior and web structure to quantify relationships between these traits, and then allowed spiders to forage for live prey on their own web or the web of a conspecific that differed in structure. Thus, we assessed how varying combinations of behavior and web structure affect foraging success, and if correlational selection might act on them. We confirmed that aggressiveness and number of gumfooted lines are positively correlated and found that capture success increased with both aggressiveness and the number of gumfooted lines. Yet, we did not find any evidence for correlational selection: aggressiveness and number of gumfooted lines appeared to affect foraging success independently of each other. These findings highlight that a correlation between traits that contribute towards the same ecological function does not necessarily imply correlational selection. Taking advantage of the experimental convenience afforded by extended phenotypic traits can provide insight into the functional consequences of phenotypic variation within and between individuals. [ABSTRACT FROM AUTHOR]

Abstract: A total of 177 naturally contaminated water samples were analyzed by membrane filtration according to the Standard Methods for the Examination of Water and Wastewater published by the American Public Health Association. Filters were incubated in parallel on mHPC-agar and 3M™ Petrifilm™ Aerobic Count Plates (Petrifilm™ AC plates) for heterotrophic counts. Fecal coliforms and Escherichia coli were enumerated on mFC-agar and 3M™ Petrifilm™ E. coli/Coliform Count Plates (Petrifilm™ EC plates). Typical colonies on each media type were confirmed following standard procedures. Heterotrophic counts were between 103 and 104 CFU/mL and the average log10 counts obtained on Petrifilm™ AC plates were about two-fold lower than on mHPC-agar. Counts for fecal coliforms and E. coli were between 102 and 103 CFU/mL. Average log10 counts for confirmed fecal coliforms obtained on Petrifilm™ EC plates were slightly lower than on mFC agar with a correlation coefficient of 0.949. The average log10 counts for confirmed E. coli on Petrifilm™ EC plates and on mFC agar were statistically not different (P=0.126) with a correlation coefficient of 0.879. Specificity of Petrifilm™ EC plates and mFC agar was evaluated by comparing typical colony counts with confirmed counts. On mFC agar, counts for typical colonies were by 2 log10 CFU higher than the actual confirmed counts. In contrast, on Petrifilm™ EC plates typical colony counts were almost identical to confirmed colony counts for both fecal coliforms and E. coli. This comparison illustrates the high specificity of Petrifilm™ EC plates for enumeration of both fecal coliforms and E. coli in water. [Copyright &y& Elsevier]

Abstract: A laboratory-scale submerged anaerobic membrane bioreactor (SAnMBR) was used for thermomechanical pulping whitewater treatment. Sludge cake formation on membrane surfaces was identified as the dominant mechanism of membrane fouling. The spatial distribution of physical, chemical and microbiological structure of cake layers was characterized by various analytical techniques, including micro-tome slicing technique, confocal laser scanning microscopy (CLSM), conventional optical microscopy (COM), scanning electron microscopy (SEM)-energy-dispersive X-ray analyzer (EDX), particle size distribution (PSD) analysis, Fourier transform infrared (FTIR) spectroscopy, extraction and chemical analysis of extracellular polymeric substances (EPS), and polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE). The results showed that the areal porosity decreased from the top layer to the bottom layer. Smaller flocs had a higher tendency to accumulate on membrane surfaces but the consolidation of cake sludge in the bottom layers resulted in larger flocs as compared to the fresh cake sludge formed on the top layers. There was an increase in the bound EPS density (mgEPS/cm3 wet sludge) and a decrease in the ratio of proteins to polysaccharides in bound EPS from the top to bottom layers. PCR-DGGE study showed that there were significant differences in microbial community population density along the cake layer depth. Through the CLSM and COM images, cake layer was found to have a loose outer surface when compared with the cake bottom. The results provide a new insight in cake layer structure and suggest that structures change significantly from the top layer to the bottom layer. [Copyright &y& Elsevier]

Abstract: In this study, a Sphingomonas Strain 264 isolated from pulp and paper biofilms was used for electrochemical studies towards applications in biosensor development based on its high ability to produce extracellular polymeric substances (EPS), along with its rapid growth and tendency to flocculate. The Strain 264 biofilm was directly grown on an Au thin film and was studied with a combination of optical and electrochemical methods. The Strain 264 biofilm is stable in a wide potential range from −0.7V to 1.0V versus SCE; it is partially oxidized when the potential is above 1.0V. In addition, the Strain 264 biofilm was used as an immobilization matrix for biosensor fabrication using horseradish peroxidase (HRP) as a model enzyme. Our electrochemical measurements show that the fabricated biosensor based on immobilized HRP in the Strain 264 biofilm exhibits a wide linear range (1–18mM) and a high sensitivity (90μAmM−1) for H2O2 detection, demonstrating that the formed biofilm provides a favourable microenvironment for enzyme to retain its activity. This study has also shown that direct growth of biofilms is a feasible and effective approach for promising applications of biofilms in electrochemical biosensor development. [Copyright &y& Elsevier]