Effects of commuting and mode of transportation on performance, affect, cardiovascular activity, and frustration tolerance

It was hypothesized that making a commute elevates blood pressure, causes negative affect, reduces frustration tolerance, and impairs performance on simple and complex cognitive tasks. This hypothesis was tested by varying choice and type of commute in an experiment in which 168 volunteers were randomly assigned to one of six experimental conditions. The behavior of subjects who drove 30 miles or rode on a bus for the same distance were compared with the reactions of students who did not commute. Multivariate analyses of variance indicated that subjects who made the commute showed lower frustration tolerance and deficits on complex cognitive task performance. Commuting also raised pulse and systolic blood pressure. Multivariate analyses of covariance (MANCOVA) were performed in an effort to identify physiological and emotional reactions that may mediate these relations. No mediational relationships were uncovered. ^

Flanerie: A post -reflexive mode of urban research inquiry

Urban ethnographic studies in social science usually proceed from within a pre-figured research framework that guides field activity and filters what is considered see-worthy and study-worthy to those phenomena which are in some way necessary for the fulfillment of specific research agendas. Reliance on formalized ethnographic research methods to explore the city, and the reflex to intellectualize that which is observed by using them, frequently leads to the neglect of much of what comprises the ethnographic richness of city-life through an overly-contemplative intellectuocentrism. ^ Flânerie, an avocational, proto-sociological ethnographic mode of urban exploration and observation originating in early-nineteenth-century Paris, is representative of an alternate approach to exploration and study of the city—one less subject to a compressed horizon of ethnographic experience. It affords insight into a broad range of phenomena taking place in interstitial urban space and time which often escape the instrumentally overly-determined gaze of professionalist research inquiry. ^ The present work addressed the fact that the concept of flânerie , though occasionally invoked in discussions of methodology in urban sociology and cultural studies, had not been subjected to a systematic attempt to relate it to the research methods of these disciplines. Though as a typological figure the flâneur is thought to have disappeared long ago, practices represented by the concept continue to be engaged in by persons inside and outside of academia who approach city life and social science with a perspective somewhat transcending the reified dichotomies of private-professional and art-and-science. This study transferred aspects of the experience of the city embodied in the flâneur to the realm of ethnographic urban studies and the building of grounded social theory, finding flânerie to be crucial to the development of a refined knowledge of urban life, and an important means by which previously overlooked social phenomena and silenced avenues of research inquiry might be exposed. ^ The conclusions reached found a “flâneuristic” approach to the city as being beneficial to research practice and the vitalization of urban ethnographic inquiry, by affording opportunities for exposure to, and immersion within, an expanded range of quotidian social phenomena that have frequently escaped the academicist gaze. ^

Contribution of lipophilic secondary metabolites to the toxicity of strains of freshwater cyanobacterial harmful algal blooms, identified using the zebrafish (Danio rerio) embryo as a model for vertebrate development

Cyanobacteria ("blue-green algae") are known to produce a diverse repertoire of biologically active secondary metabolites. When associated with so-called "harmful algal blooms", particularly in freshwater systems, a number of these metabolites have been associated—as "toxins", or commonly "cyanotoxins"—with human and animal health concerns. In addition to the known water-soluble toxins from these genera (i.e. microcystins, cylindrospermopsin, and saxitoxins), our studies have shown that there are metabolites within the lipophilic extracts of these strains that inhibit vertebrate development in zebrafish embryos. Following these studies, the zebrafish embryo model was implemented in the bioassay-guided purification of four isolates of cyanobacterial harmful algal blooms, namely Aphanizomenon, two isolates of Cylindrospermopsis, and Microcystis, in order to identify and chemically characterize the bioactive lipophilic metabolites in these isolates. ^ We have recently isolated a group of polymethoxy-1-alkenes (PMAs), as potential toxins, based on the bioactivity observed in the zebrafish embryos. Although PMAs have been previously isolated from diverse cyanobacteria, they have not previously been associated with relevant toxicity. These compounds seem to be widespread across the different genera of cyanobacteria, and, according to our studies, suggested to be derived from the polyketide biosynthetic pathway which is a common synthetic route for cyanobacterial and other algal toxins. Thus, it can be argued that these metabolites are perhaps important contributors to the toxicity of cyanobacterial blooms. In addition to the PMAs, a set of bioactive glycosidic carotenoids were also isolated because of their inhibition of zebrafish embryonic development. These pigmented organic molecules are found in many photosynthetic organisms, including cyanobacteria, and they have been largely associated with the prevention of photooxidative damage. This is the first indication of these compounds as toxic metabolites and the hypothesized mode of action is via their biotransformation to retinoids, some of which are known to be teratogenic. Additional fractions within all four isolates have been shown to contain other uncharacterized lipophilic toxic metabolites. This apparent repertoire of lipophilic compounds may contribute to the toxicity of these cyanobacterial harmful algal blooms, which were previously attributed primarily to the presence of the known water-soluble toxins.^