An explanation of the behavioral origin of moderation in the use of natural resources: a meta-synthesis study

Environment Systems and Decisions - Natural resources are a type of good whose individual utility maximization is not desirable, as it could lead to their depletion. This problem, raised several...     

Fetal renal anomalies and genetic syndromes

Renal abnormalities are some of the commonest and most easily detectable anomalies on ultrasound. Many are an isolated finding but the prognosis may be altered considerably by the detection of other anomalies which could indicate a genetic disorder or syndrome. It is often easier to detect presupposed anomalies and the purpose of this article is to introduce and discuss those syndromes that may present with a renal abnormality on ultrasound. Common renal findings are presented with the range of additional anomalies that should be sought and suggested diagnostic tests. It should be remembered that although for many genetic conditions specific mutation analysis is now available, this usually requires pre‒pregnancy investigations. Furthermore, in some cases the definitive diagnosis may not be suspected until post mortem. By this time it may be too late to establish a cell line to confirm the suspicion using laboratory methods. It is therefore important to take tissue samples antenatally where possible, or at delivery, as postnatal samples may have a high culture failure rate. Copyright © 2001 John Wiley & Sons, Ltd.     

Enantiomeric separation of metolachlor and its metabolites using LC-MS and CZE

The stereoisomers of metolachlor and its two polar metabolites [ethane sulfonic acid (ESA) and oxanilic acid (OXA)] were separated using liquid chromatography-mass spectrometry (LC-MS) and capillary zone electrophoresis (CZE), respectively. The separation of metolachlor enantiomers was achieved using a LC-MS equipped with a chiral stationary phase based on cellulose tris(3,5-dimethylphenyl carbamate) and an atmospheric pressure chemical ionization source operated under positive ion mode. The enantiomers of ESA and OXA were separated using CZE with gamma-cyclodextrin (gamma-CD) as chiral selector. Various CZE conditions were investigated to achieve the best resolution of the ESA and OXA enantiomers. The optimum background CZE electrolyte was found to consist of borate buffer (pH=9) containing 20% methanol (v/v) and 2.5% gamma-CD (w/v). Maximum resolution of ESA and OXA enantiomers was achieved using a capillary temperature of 15 degrees C and applied voltage of 30 kV. The applicability of the LC-MS and CZE methods was demonstrated successfully on the enantiomeric analysis of metolachlor and its metabolites in samples from a soil and water degradation study that was set up to probe the stereoselectivity of metolachlor biodegradation. These techniques allow the enantiomeric ratios of the target analytes to be followed over time during the degradation process and thus will prove useful in determining the role of chirality in pesticide degradation and metabolite formation.     

Teil 1: PCDD/F in Böden,Vegetation und Kuhmilch

Soil samples were taken from residential gardens, grasslands and forests at 22 locations in Marsberg, North Rhine-Westphalia, and analyzed for PCDD/F. Sampling was concentrated on the vicinity of a former copper smelter where copper waste material (calledKieselrot) was deposited and emissions from former stacks contaminated a large land area. Maximum PCDD/F-concentrations were 407 ng TE GBA/kg dm in garden soil (0–30 cm depth), 98 ng TE BGA/kg dm in agricultural grassland (0–10 cm depth), 227 ng TE BGA/kg dm in wasteland, and up to 8073 ng TE BGA/kg dm in forest soils. PCDD/F-levels in soil decreased with increasing distance from the former sources providing a large historic emission problem, apart from the still existing kieselrot waste site. Ash residues from former flue gas duct showed up to 2,4 mg TE BGA/kg dm. PCDD/F-concentrations in vegetable samples from highly contaminated garden soils and grass from agricultural grassland were found to be relatively low in relation to soil values. PCDD/F-levels in salad showed a mean of 2,2 ng TE BGA/kg dm while grass concentrations were <6 ng TE BGA/kg dm. Thus, no correlation was found between soil and vegetation values with the exception for carrot roots where obviously a small transfer of PCDD/F between the two media took place. PCDD/F-content in grass taken over the vegetation period showed a tendency to increase toward the end of the growing season, which is probably related to changes in the dry matter yield over the season. No correlation was found in general between soil, grass and milk PCDD/F contents when all samples were taken from the same grassland. PCDD/F-concentrations in milk ranged between 0,6 and 1,1 pg TE BGA/g milkfat and were thus in the same range as consumer milk in the Federal Republic of Germany. PCDD/F in needles from conifers showed a clear relationship with respect to distance from the former waste site. The relatively high levels in conifer needles [36 ng TE BGA/kg dm] were obviously due to sporting activities (i.e. motocross racing where contaminated material was resuspended and deposited on surrounding trees).     

Atrazine induction of a family 4 cytochrome P450 gene in Chironomus tentans (Diptera: Chironomidae)

Cytochrome P450-dependent microsomal monooxygenase (P450) activity was measured in control and atrazine-exposed third instar midge larvae, Chironomus tentans. Significantly elevated O-demethylase activity was observed in gut homogenates taken from midges exposed to atrazine concentrations from 1 to 10 ppm for 90 h. No significant induction was observed at atrazine concentrations below 1 ppm. A region of a cytochrome P450 family 4 gene was amplified and sequenced from C. tentans larvae. Alignments of inferred amino acid sequences with other insect CYP4 gene homologues indicate a high degree of similarity. Northern blot analysis employing the CYP4 gene fragment as a probe showed an over-expression in C. tentans exposed to atrazine. The results support the previously identified inducibility of cytochrome P450-dependent activity and provide insight into the potential consequences of atrazine exposure to aquatic organisms.     

Double-conscious professional self-expression of racial minority scientists-in-training

Double-consciousness pervades the workplace experiences of minority professionals. Prior research captures various manifestations of double-consciousness in the workplace, yet much of what we know comes from understanding the experiences of minority professionals in predominantly White workplaces. Inherent in conceptions of double-consciousness is the sense of twoness in one's self concept that arises from seeing oneself through the eyes of both the predominantly White profession and one's own racial community. In this study, we examine contrasts as well as commonalities in experiences of double-consciousness across different social contexts in the socialization of minority scientists-in-training. We draw from qualitative data collected from 64 individuals (including 39 underrepresented minority doctoral students, and 25 faculty, staff, and administrators) in science, technology, engineering, and mathematics (STEM) doctoral programs in both predominantly White and historically Black institutions to examine and compare the factors across different contexts that influence how minority scientists-in-training are able to express their emerging professional identity. Our findings reveal how minority scientists-in-training experience twoness as both a struggle and a strength, and we develop an inductive model of how different socializations influence the double-conscious professional self-expressions of minority scientists in training.