LARGE WOODY DEBRIS IN URBAN STREAM CHANNELS: REDEFINING THE PROBLEM

Large woody debris (LWD) is an important ecological element in rivers and streams. Despite its importance, LWD is often removed from urban stream channels for flood control or road maintenance purposes, an approach with high economic and ecological costs and one that is largely unsuccessful. We propose an approach to conserve LWD in channels by modifying infrastructure (culverts and bridges) to allow LWD passage, maintaining aquatic habitat and reducing flooding and road maintenance costs. In Soquel Creek (California, USA), which has a history of LWD‐related flooding, we compared long‐term LWD management costs of historical, current and a LWD‐passing approach whereby infrastructure is enlarged to accommodate LWD passage downstream. We estimated costs of infrastructure replacement, programmatic flood control (LWD removal), LWD‐related flood damage and lost aquatic habitat. The amount of lost aquatic habitat was determined by comparing LWD loading (pieces m^?1) in Soquel Creek (0.007 pieces m^?1) to nearby unmanaged streams (0.054 to 0.106 pieces m^?1). Estimated costs of infrastructure able to pass LWD were nearly double that of historical costs but comparable to current costs. The LWD‐passing approach was comparable to removal approaches in the short term (1 to 50 years) but much less in the long term (51 to 100 years), as expenditures in infrastructure replacement to accommodate LWD yielded reductions in flooding costs and habitat loss. Given the urgency to maintain and restore aquatic habitat, the proposed approach may be broadly applicable. Copyright © 2011 John Wiley & Sons, Ltd.     

Use of Visual, Acoustic, and Olfactory Information During Embedded Invertebrate Foraging in Brown Capuchins (Cebus apella).

Experiments were conducted to investigate which sensory cues are used by brown capuchins (Cebus apella) in embedded invertebrate foraging. The importance of visual, olfactory, and acoustic cues in such foraging was determined by presenting subjects with a stimulus log modified to block out given sensory cues. Experiment 1 was designed to investigate whether subjects could locate an invertebrate embedded in wood when only visual, acoustic, or olfactory information was available. Experiments 2 and 3 were designed to investigate extractive foraging behavior when two sensory cues were provided. It was hypothesized that the combination of visual and acoustic information would be necessary for subjects to successfully locate embedded invertebrates. Results indicated that subjects' performance was most successful when both visual and acoustic information was available. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of the biomass in the modelling and simulation of the biofiltration of hydrogen sulphide: simulation and experimental validation

BACKGROUND: Several models have been developed to simulate the decay of pollutants concentration along the biofilter and to predict its performance. Despite the evidence, it is common that most models ignore the effect of variable biomass along the biofilter. An equation that represents the variable amount of active biomass along the column was included in the modelling of a biotrickling filter; it was obtained by measuring the active biomass at different heights. Validation of the model was carried out using experimental data obtained at different H₂S loads. RESULTS: The simulation considering the expression for variable active biomass along the column shows better correlation with experimental results. With the diffusion coefficient that shows the best fit with the experimental results; 1.35 × 10^?9 m² s^?1, the value of the Thiele module is 2 × 10^?3, indicating that biooxidation of H₂S is controlled by mass transfer. CONCLUSIONS: A better correlation between experimental results and model prediction is obtained when the expression for variable active biomass along the column is considered in the modelling. Copyright © 2010 Society of Chemical Industry     

A quantitative comparison of the extraction of protein fractions from wheat grain by different solvents,and of the polypeptide and amino acid composition of the alcohol-soluble proteins

Using several cultivars, whole milled wheat grain was first extracted with 0.5M NaCl to remove non-protein N, albumins and globulins: the amount of protein subsequently extractable by either 70% ethanol, 55% propan-2-ol, or 50% propan-1-ol (with or without the addition of acetic acid), was then compared. All solvents were tested at 4, 20 and 60°C both with and without the addition of 2-mercaptoethanol (2-ME) as a reducing agent. Raising the temperature, including a reducing agent, and repeated extractions, all combined to maximise protein extractability; least was extracted by 70% ethanol at 4°C and most by 50% propan-1-ol containing acetic acid and 2-ME at 60°C. The differing polypeptide compositions of these alcohol-soluble fractions illustrated why N solubility alone is not a sufficient guide to protein extraction, e.g. 35% of grain N was extractable by either 70% ethanol at 60°C or 70% ethanol containing 2-ME at 4°C, but high mol. wt polypeptides (>60000) were found only in the 60°C extract. In contrast, the complete range of alcohol-soluble polypeptides was extracted by all solvent mixtures based on propan-1-ol, even at 4°C. Amino acid analyses of these alcohol-soluble fractions confirmed the low levels of lysine in fractions free from high mol. wt polypeptides. More glycine was found in all fractions containing high mol. wt polypeptides, but only those extracted by propan-1-ol mixtures had an increased lysine content, the amount of which increased linearly as the extraction temperature was raised. Defatting the milled grain did not affect the extractability of alcohol-soluble proteins, but the amount of protein soluble in 0.5M NaCl decreased. The protein rendered NaCl-insoluble was not extracted by any of the alcoholic solvents tested, hence the N content of the residual material was increased. The inclusion of this denatured metabolic fraction in the residue will affect its amino composition. The problems arising from the retention of the classical nomenclature for Osborne-type fractions are discussed.     

Visual discrimination by heifers (Bos taurus) of their own species.

Species discrimination has been described in several taxa but rarely in domestic animals. In contrast to wild species, domestic species present a great phenotypic variety. This study investigated whether 10 Prim'Holstein heifers (Bos taurus) could discriminate images of cows from images of other domestic animals. The experiment was based on simultaneous discrimination. Responses were obtained through instrumental conditioning using a food reward. In Experiment 1, the reward was associated with a cow face and, in the reversal learning task, with faces of other domestic species. The results showed that in both tasks, cows were able to reach the criterion in few sessions. Therefore, despite great phenotypic variety (a cognitive challenge) cows were able to visually discriminate their own species from other domestic species. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Alterations of the phylloepiphytic bacterial community associated with interactions of Escherichia coli O157:H7 during storage of packaged spinach at refrigeration temperatures

This study investigated the effects of packaging and storage temperature on the spinach phylloepiphytic bacterial community and fate of Escherichia coli O157:H7. Freshly harvested spinach was rinsed and/or disinfected, packaged and stored under typical retail conditions (4 °C) or under temperature abuse conditions (10 °C) for a period of 15 days. The final population size of culturable epiphytic bacteria after 15 days of storage was not affected by the temperature of storage or the presence of E. coli O157:H7. However, analysis of the bacterial community using denaturing gradient gel electrophoresis of 16s rDNA revealed changes with time of storage and the presence of E. coli O157:H7. Excision and sequencing of prominent DGGE bands identified that the majority of sequences belonged to the phyla Actinobacteria, Bacteroidetes, Firmicutes and Alphaprotebacteria. After 10 days of storage at 4 °C or 10 °C the population became more dominated by psychrotrophic bacteria. Removal of the epiphytic bacteria resulted in significant increases in numbers of E coli O157:H7 at 10 °C and was associated with decreased expression of E. coli O157:H7 virulence (stxA, curli, eaeA) and stress response (rpoS, sodB) genes. In conclusion, storage temperature and time of storage of packaged spinach affected the diversity of the epiphytic spinach microbiota which influenced the growth, establishment, physiology and potentially virulence of E. coli O157:H7.     

Self-system therapy as an intervention for self-regulatory dysfunction in depression: A randomized comparison with cognitive therapy.

Self-system therapy (SST) is a new therapy based on regulatory focus theory (E. T. Higgins, 1997) for depressed individuals unable to pursue promotion goals effectively. The authors conducted a randomized trial comparing SST with cognitive therapy (CT) in a sample of 45 patients with a range of depressive symptoms to test 2 hypotheses: that SST would be more efficacious for depressed individuals characterized by inadequate socialization toward pursuing promotion goals and that SST would lead to greater reduction in dysphoric responses to priming of promotion goals. There was no overall difference in efficacy between treatments, but patients whose socialization history lacked an emphasis on promotion goals showed significantly greater improvement with SST. In addition, SST patients showed a greater reduction in dysphoric responses to promotion goal priming than did CT patients. The results illustrate the value of a theory-based translational approach to treatment design and selection. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Derivation and prediction of temperamental types among preschoolers.

The number and nature of temperamental types in 488 children aged 3 years 6 months was examined on the basis of a broad set of temperamental characteristics, including positive and negative emotionality and the attentional and behavioral control domains. Configural frequency analysis methods showed clear support for two temperament types: controlled–nonexpressive and noncontrolled–expressive. These types showed meaningful differences against external criteria related to a wide range of problem behaviors from the emotional, social, and attentional domains. The reports of problem behaviors were obtained contemporaneously from fathers and caregivers. These findings replicated a year later when children were aged 4 years 6 months. Furthermore, the findings showed that infant and toddler-age temperamental characteristics differentiated these preschool-aged types. The authors discuss the implications of the results for a categorical view of temperament–personality. (PsycINFO Database Record (c) 2010 APA, all rights reserved)