Social identity in construction: enactments and outcomes

A social identity lens and theories of self-reinforcement are used to explore identity work and processes of identification at the micro-level in a large construction company. Rich data from a qualitative case study show that a strong collective identification is self-defining for the vast majority of managers in the organization, regardless of their role and function. This collective identification revolved around the trade of ‘being a construction worker’, associated with the traits of being practically oriented and of having a long professional background in construction. This collective identification seems to reinforce itself by a combination of pulling and pushing movements and/or ‘being blind’ vis-à-vis those that stand outside its self-defining core, content, and behaviours. The results of the study suggest that self-defining at the individual and group levels has implications for organizational performance and outcomes. It is also suggested that the use of a social identity lens can help increase understanding of interpersonal relations, collaboration, and change initiatives in the construction industry.     

Forced Relocation in France: How Residential Trajectories Affect Individual Experiences

In France, an urban renewal programme was launched in 2003 with the aim of boosting social mix by diversifying housing in disadvantaged neighbourhoods known as ‘Sensitive Urban Zones’. Drawing on 121 qualitative interviews conducted in seven neighbourhoods in the Paris region, this article focuses on relocation processes triggered by the demolition of social housing. How are these socio-residential changes experienced by those actually being relocated? To answer this question, the paper shows how an analysis of long-term residential trajectories can highlight and nuance the experiences of relocatees. Three broad types of trajectories are defined as an analytical framework for a comprehensive approach of the meaning of relocation and opportunity held by households. It shows how forced relocation can either be a positive step in residential trajectories or merely an adaptation in terms of housing, whether or not the inhabitants actually stay in their neighbourhood or leave it.     

Modellbasierte Berechnung der Abfluss- und Stofftransportprozesse in hierarchisch organisierten Karstnetzwerken

Karst systems fed by an allogenic inflow often show a complex network of interacting conduits that effects groundwater flow and pollutant transport. The combined evaluation of multi-tracer experiments performed at different flow conditions provide information about the hydrodynamic functioning of the karst network. Building on this, a conceptual model to quantify groundwater flow and mass transport has been developed and is presented in this study using the example of the Tanneben Massif, Austria. Within the model, groundwater flow is subdivided into several flow-paths with discrete flow velocity and capacity. As a consequence, model results reveal a dampen but also extended karst response to storm events. Upon exceeding the flow capacity, backwater accumulates at the inflow causing a prolongation of high discharge into the system. Additionally, adjacent karst systems are affected by the activation of interconnecting flow paths at high flow conditions.     

Glycation of caseinate by fructose and fructo‐oligosaccharides during controlled heat treatment in the ‘dry’ state

This paper investigates the controlled heating of caseinate with reducing sugars to produce glycoproteins with improved functionality for use in food. Caseinate was combined with inulin, fructose and a mixture of both inulin and fructose and the lyophilisates heated at a controlled water activity for up to 48 h. Caseinate–glucose and caseinate–lactose glycoconjugates were prepared for comparison. Conjugation between caseinate and fructose occurred readily at 60 °C and 67% relative humidity, modifying up to 75% of the lysine groups of caseinate within 48 h. Moreover, when reconstituted, the caseinate–fructose glycoconjugates showed a dramatic increase in viscosity relative to caseinate ‘dry’‐heated alone. At 80% relative humidity the reaction proceeded so rapidly that gels containing darkly coloured particulate matter were formed. Incorporation of inulin prevented formation of caseinate–fructose gels, and minimised browning development while still producing moderately viscous solutions. Based on ¹³C‐NMR, SDS‐PAGE and electron microscopy techniques, mechanisms by which inulin modified the reaction have been proposed. Copyright © 2005 Society of Chemical Industry     

Chlorine isotope analysis of organic contaminants using GC-qMS: method optimization and comparison of different evaluation schemes

Compound-specific online chlorine isotope analysis of chlorinated hydrocarbons was evaluated and validated using gas chromatography coupled to a regular quadrupole mass spectrometer (GC-qMS). This technique avoids tedious off-line sample pretreatments, but requires mathematical data analysis to derive chlorine isotope ratios from mass spectra. We compared existing evaluation schemes to calculate chlorine isotope ratios with those that we modified or newly proposed. We also tested systematically important experimental procedures such as external vs. internal referencing schemes, and instrumental settings including split ratio, ionization energy, and dwell times. To this end, headspace samples of tetrachloroethene (PCE), trichloroethene (TCE), and cis-dichloroethene (cDCE) at aqueous concentrations in the range of 20-500 μg/L (amount on-column range: 3.2-115 pmol) were analyzed using GC-qMS. The results (3?Cl/3?Cl ratios) showed satisfying to good precisions with relative standard deviations (n = 5) between 0.4‰ and 2.1‰. However, we found that the achievable precision considerably varies depending on the applied data evaluation scheme, the instrumental settings, and the analyte. A systematic evaluation of these factors allowed us to optimize the GC-qMS technique to determine chlorine isotope ratios of chlorinated organic contaminants.     

Salivary cotinine concentration versus self-reported cigarette smoking: Three patterns of inconsistency in adolescence.

The present study examined the extent and sources of discrepancies between self-reported cigarette smoking and salivary cotinine concentration among adolescents. The data are from household interviews with a cohort of 1,024 adolescents from an urban school system. Histories of tobacco use in the last 7 days and saliva samples were obtained. Logistic regressions identified correlates of three inconsistent patterns: (a) Pattern 1-self-reported nonsmoking among adolescents with cotinine concentration above the 11.4 ng/mg cutpoint (n = 176), (b) Pattern 2-low cotinine concentration (below cutpoint) among adolescents reporting having smoked within the last 3 days (n = 155), and (c) Pattern 3-high cotinine concentration (above cutpoint) among adolescents reporting not having smoked within the last 3 days (n = 869). Rates of inconsistency were high among smokers defined by cotinine levels or self-reports (Pattern 1 = 49.1%; Pattern 2 = 42.0%). Controlling for other covariates, we found that reports of nonsmoking among those with high cotinine (Pattern 1) were associated with younger age, having few friends smoking, little recent exposure to smokers, and being interviewed by the same interviewer as the parent and on the same day. Low cotinine concentration among self-reported smokers (Pattern 2) was negatively associated with older age, being African American, number of cigarettes smoked, depth of inhalation, and exposure to passive smoke but positively associated with less recent smoking and depressive symptoms. High cotinine concentrations among self-reported nonsmokers was positively associated with exposure to passive smoke (Pattern 3). The data are consonant with laboratory findings regarding ethnic differences in nicotine metabolism rate. The inverse relationship of cotinine concentration with depressive symptoms has not previously been reported. Depressed adolescent smokers may take in smaller doses of nicotine than nondepressed smokers; alternatively, depressed adolescents may metabolize nicotine more rapidly.     

Complex Microwave Permittivity of Secondary High Explosives

We aim to understand how microwaves interact with high explosives by studying the complex permittivity from 1–18 GHz of HMX, RDX, TNT, TATB, PETN, Octol, Comp B, 95 % RDX/5 % Viton A (PBX‐RDX), PBX 9404, PBXN‐5, PBXN‐7, PBXW‐14, PBX 9501, and PBX 9502. The combination of a resonant cavity perturbation technique for determining the room‐temperature complex dielectric constant at discrete frequencies and a wide band open circuit method (1–18 GHz) provides an accurate, broadband measurement that describes the dielectric properties in the frequency range of interest. While the values of the real and imaginary permittivity components did not vary significantly as a function of frequency, we found the real part of the permittivity to be highly dependent on relatively small changes in the material density. We used dielectric mixing theory, specifically the linear‐law approximation, to compare the predicted values based on the dielectric properties of individual components with those of the resulting formulation measured experimentally for a select number of samples; the prediction agrees well within the observed variability of the experimentally measured values.     

Boysenberry and blackcurrant drinks increased the plasma antioxidant capacity in an elderly population but had little effect on other markers of oxidative stress

BACKGROUND: The consumption of fruit and vegetables promotes good health by protecting against various degenerative diseases. Even though the constituents responsible are not known, some evidence indicates that the antioxidant properties of fruit and vegetable phytochemicals are responsible. Previous studies have shown that blackcurrant and Boysenberry reduce oxidative stress using in vitro cell systems. The aim of this study was to determine if blackcurrant or Boysenberry drinks could improve measures of oxidative stress and inflammation in an elderly population with below‐average memory abilities. The intervention parallel study was fully blinded with a placebo control. RESULTS: Of the six measures of oxidative stress assessed, only plasma antioxidant capacity significantly increased for both the Boysenberry and blackcurrant treatments compared with the placebo. Plasma malondialdehyde decreased in both the Boysenberry and blackcurrant treatments although the decrease was not statistically significant. Measures of oxidative stress for protein oxidation and lipid peroxidation improved for the berryfruit treatments during the study but were not statistically different from the placebo. CONCLUSION: Long‐term consumption of both the Boysenberry and blackcurrant drinks raised the plasma total antioxidant capacity of the study participants suggesting that Boysenberry and blackcurrant may help protect against oxidative stress‐related health conditions. Copyright © 2007 Society of Chemical Industry     

Effects of processing and storage on juice colour and betacyanin stability of purple pitaya (<Emphasis Type="Italic">Hylocereus polyrhizus</Emphasis>) juice

Purple pitaya (Hylocereus polyrhizus) fruits have been recently proposed as a promising source of betalains. In the present study, purple pitaya juice processing at pilot-plant scale is reported for the first time. Each processing step was examined in terms of juice colour and betacyanin retention. Lightness (L ^*) and hue angle (h°) values were strongly influenced by juice filtration, while chroma (C ^*) and betacyanin retention were most strongly altered by pasteurisation. Three systems of juice pasteurisation were evaluated. Betacyanin loss and colour alteration were minimal upon pasteurisation in an HTST system and a standard tubular heat exchanger, respectively. Additionally, storage experiments using mucilage-free purple pitaya juice were conducted. Whereas light exposure of unsupplemented samples resulted in significant pigment degradation, detrimental effects of light exposition were completely prevented by the addition of 1% ascorbic acid prior to storage. After 6 months, about 70% of the initial betacyanin content was retained in the presence of ascorbic acid, irrespective of illumination.     

Comparison of the 2,2'-azinobis-3-ethylbenzotiazo-line-6-sulfonic acid (ABTS) and ferric reducing anti-oxidant power (FRAP) methods to asses the total antioxidant capacity in extracts of fruit and vegetables

A comparison was made on the use of two spectrophotometric methods, the ferric reducing antioxidant power (FRAP) method and the 2,2'-azinobis-3-ethylbenzotiazoline-6-sulfonic acid (ABTS) method, for the measurement of the total antioxidant capacity (TAC) of plant foods. The correlations of TAC measured by the two methods were highly significant in both water-soluble (r2= 0.90) and water-insoluble extracts (r2= 0.98) from 13 strawberry samples. Also a corresponding comparison of TAC in extracts from 14 plant species showed high correlation coefficients, r2= 0.98 for water-soluble extracts and r2= 0.88 for water-insoluble extracts. The ratio of TAC values obtained with the two methods (ABTS/FRAP) varied between 0.7 and 3.3 for different plant extracts indicating that they contained antioxidants with varying reactivity in the two methods. TACs in six pure antioxidant substances were ranked in the following order by both methods: quercetin > ferulic acid > catechin > rutin > caffeic acid > Trolox = chlorogenic acid. The two methods showed similar TAC values for quercetin, rutin, caffeic acid and chlorogenic acid while ferulic acid and catechin gave higher results with the ABTS method than with the FRAP method, and such differences probably explain the varying ratios of ABTS/FRAP obtained in foods. Regarding storage TAC in water-soluble strawberry extracts stored at -20 or -80 degrees C was stable for at least five months while storage at 4 degrees C decreased the TAC value with 40% during five weeks of storage. The study showed that both the ABTS and FRAP methods can be used for convenient monitoring of the antioxidant capacities in fruit and vegetables, and that different antioxidants had varying reactivity in the two methods.