A stable genetic polymorphism underpinning microbial syntrophy

Syntrophies are metabolic cooperations, whereby two organisms co-metabolize a substrate in an interdependent manner. Many of the observed natural syntrophic interactions are mandatory in the absence of strong electron acceptors, such that one species in the syntrophy has to assume the role of electron sink for the other. While this presents an ecological setting for syntrophy to be beneficial, the potential genetic drivers of syntrophy remain unknown to date. Here, we show that the syntrophic sulfate-reducing species Desulfovibrio vulgaris displays a stable genetic polymorphism, where only a specific genotype is able to engage in syntrophy with the hydrogenotrophic methanogen Methanococcus maripaludis. This 'syntrophic' genotype is characterized by two genetic alterations, one of which is an in-frame deletion in the gene encoding for the ion-translocating subunit cooK of the membrane-bound COO hydrogenase. We show that this genotype presents a specific physiology, in which reshaping of energy conservation in the lactate oxidation pathway enables it to produce sufficient intermediate hydrogen for sustained M. maripaludis growth and thus, syntrophy. To our knowledge, these findings provide for the first time a genetic basis for syntrophy in nature and bring us closer to the rational engineering of syntrophy in synthetic microbial communities

Bifactor analysis of motivation for charity sport event participation

The purpose of this study was to examine the utility of the existing subscales of charity sport events (CSEs) participation motivation by adopting both a second-order modeling and a bifactor modeling approaches. The results with 488 college students revealed that the bifactor model provided a better interpretation of the data compared to second-order model. The five-factor CSE motivation significantly predict the intention to participate in CSEs along with two domain-specific motivations, namely ‘sport and event’ and ‘cause’ while other three domain-specific motivations including ‘philanthropic’, ‘social interaction’, and ‘reference group’ are not statistically significant predictors. The results suggest that the bifactor model is more useful in predicting this group’s participation in charity sport events. © 2015, Springer-Verlag Berlin Heidelberg

Road agency practices. Part B., External consultation for road strategy development

http://trove.nla.gov.au/work/2486660

Willingness to pay : Australian consumers and “on the farm” welfare

The success of welfare legislation for nonhuman animals rests upon primary producer compliance that, in turn, is affected by public willingness to pay (WTP)for such initiatives. Although the topic of the welfare of animals on farms (and relevant legislation) is becoming increasingly important to the Australian public, there remain relatively few recent assessments of the variables that may affect WTP and, therefore, support initiatives aimed at improving the welfare of animals living on farms. This study surveyed 1,224 community members in Queensland, Australia. The study assessed respondents’ self-rated knowledge of, and concern regarding, farm animal welfare. In addition, the survey asked respondents how much more they would be prepared to pay for animal-based products to ensure that they came from a source where the Five Freedoms were met. Although self-rated knowledge and level of concern were found to affect WTP, the study found only concern for farm animal welfare actually predicted consumer behavior. Further analyses showed a potential confound between knowledge levels and locality. Thisarticle discusses the implications of this for future initiatives to increase WTP