Quantification and source characterization of volatile organic compounds from exercising and application of chlorine-based cleaning products in a university athletic center

Humans spend approximately 90% of their time indoors, impacting their own air quality through occupancy and activities. Human VOC emissions indoors from exercise are still relatively uncertain, and questions remain about emissions from chlorine-based cleaners. To investigate these and other issues, the ATHLETic center study of Indoor Chemistry (ATHLETIC) campaign was conducted in the weight room of the Dal Ward Athletic Center at the University of Colorado Boulder. Using a Vocus Proton-Transfer-Reaction Time-of-Flight Mass Spectrometer (Vocus PTR-TOF), an Aerodyne Gas Chromatograph (GC), an Iodide-Chemical Ionization Time-of-Flight Mass Spectrometer (I-CIMS), and Picarro cavity ringdown spectrometers, we alternated measurements between the weight room and supply air, allowing for determination of VOC, NH₃, H₂O, and CO₂ emission rates per person (emission factors). Human-derived emission factors were higher than previous studies of measuring indoor air quality in rooms with individuals at rest and correlated with increased CO₂ emission factors. Emission factors from personal care products (PCPs) were consistent with previous studies and typically decreased throughout the day. In addition, N-chloraldimines were observed in the gas phase after the exercise equipment was cleaned with a dichlor solution. The chloraldimines likely originated from reactions of free amino acids with HOCl on gym surfaces.     

Ansel Adams and Fiat Lux

Abstract

In 1963, Clark Kerr, then President of the University of California, approached Ansel Adams and Nancy Newhall to participate in the centennial celebrations (in 1968) of the founding of the University. Adams's photographic work on the nme campuses in the years following resulted in the production of six thousand negatives, from which six hundred and five were produced as fine prints (placed in the University Archives at the Bancroft Library at Berkeley) and many others reproduced in the book, Fiat Lux (1968), with text by Nancy Newhall. In 1990, an exhibition consisting of one hundred of those photographs (to celebrate the twenty-fifth anniversary of the University of California at Irvine) toured the campuses of the University between January 1991 and May 1992, accompanied by the exhibition catalogue, Ansel Adams: Fiat Lux.     

Oral and intestinal digestion of oligosaccharides as potential sweeteners: A systematic evaluation

The utilisation of oligosaccharides by oral microorganisms and intestinal enzymes are important factors in determining their effectiveness as alternative sweeteners. In this study, classes of naturally occurring sugars were assessed using in vitro models for oral and intestinal digestibility, in order to test the influence of chemical structure on functional properties. Amongst the classes of sucrose isomers, α-glucobioses, β-glucobioses and sucrose-based oligosaccharides, structures were identified that were not utilised by the common oral bacterium Streptococcus mutans, and would therefore contribute to the non-cariogenic potential of a sweetener. Analysis of the rate and products of digestion by a rat glucosidase mixture was used to determine the relative intestinal digestibility. The results showed that oligosaccharides containing a (1 → 6)-β-Glc group, including gentiobiose and gentiobiitol, together with melezitose, a sucrose-derived oligosaccharide containing a α-Glc-(1 → 3)-Fru moiety were resistant to digestion by both S. mutans and mammalian intestinal enzymes, highlighting their potential as dietary sugar substitutes.     

Democracy and non-profit housing. The tensions of residents’ involvement in the Danish non-profit sector

Resident democracy as a special form of participatory democratic set-up is fundamental in the understanding, and self-understanding, of the non-profit housing sector in Denmark. Through a case study, the paper explores how resident democracy is perceived and narrated between residents and employees at a housing association. The study indicates that the meta-story of democracy is disconnected from practice and the lived lives of residents. Three analytical tensions structure the analysis, which relate to the conditions for realizing the democratic ideal embedded in the structure of the sector. The tensions are related to representative versus participatory democracy; collectivity versus individuality; and service versus welfare. The tensions elucidate how resident democracy is squeezed between different logics, which result in an ambiguous setting for practising democracy. Based on the results, the article discusses conditions for prospective democracy in the Danish non-profit housing sector.