YouTube,Social Norms and Perceived Salience of Climate Change in the American Mind

This online experiment explored how contextual information embedded in new media channels such as YouTube may serve as normative social cues to users. Specifically, we examined whether the number of views listed under a YouTube video about climate change would elicit inferences regarding how “others” feel about the climate issue and, consequently, might influence perceptions of issue salience. Participants in this experiment were exposed to a YouTube video about climate change using two experimental conditions, one providing a small number of views under the video and the second listing a large number of views. Results suggest that the “number of views” cue did, indeed, influence participant perceptions of the importance assigned by other Americans to the issue of climate change. Further, compared to low self-monitoring participants, high self-monitoring participants registered an increase in their own judgment of issue importance.     

Modeling organizational processes across hierarchical levels: climate,leadership, and group process in work groups

Perceptions of organizational climate, leadership, and group processes were aggregated within hierarchically nested work groups. Relationships across hierarchical boundaries were examined for two samples at different hierarchical levels in a military organization. Perceptions of climate were positively related across levels in both samples. There was evidence that the pattern of relationship among the other constructs was different in the two samples. The results have implications for the process which organizational interventions can be expected to flow through hierarchical levels of an organization. © 1997 John Wiley & Sons, Ltd.     

The simultaneous modelling of metal ion and humic substance transport in column experiments

Pulsed column experiments using Co, fulvic acid and porous sediment packing, along with up/down-flooding experiments using Eu, humic acid and intact sandstone blocks have been performed. The elution of metal and humic and their distribution along the sandstone columns have been measured. A mixed equilibrium and kinetic coupled chemical transport model has been used to simulate the results. In both cases, one exchangeable and one non-exchangeable component have been used to simulate the interaction of metal and humic substance. For the pulsed experiments, a simple equilibrium approach was used to model humic sorption, while a two component, kinetic model was required for the sandstone columns.     

AN INTERDISCIPLINARY APPROACH TO VALUING WATER FROM BRUSH CONTROL1

ABSTRACT: An analytic methodology utilizing models from three disciplines is developed to assess the viability of brush control for water yield in the Frio River basin, Texas. Ecological, hydrologic, and economic models are used to portray changes in forage production and water supply resulting from brush control, and to value supplemental water produced through brush control. Site‐specific biophysical characteristics are used to simulate water yields from brush control across the watershed. Economic benefits from increased animal production for ranchers undertaking brush control are assessed. Benefits to Corpus Christi residential water consumers from ranchers' brush control activities are evaluated using the change in consumer surplus resulting from supplemental water produced through brush control. Results indicate an increase in water yield with brush control on 35 percent of the land area in the basin. However, the cost of brush control is more than the increase in returns it fosters on most range sites. Consumer surplus change for Corpus Christi residents over 25 years is zero under baseline conditions, implying subsidies for brush control in the Frio basin are not worthwhile at this time.     

Cytotoxic activity of spark‐decomposed sulfur hexafluoride and analysis of cytotoxic contributions of individual spark decomposition products†

Sulfur hexafluoride decomposed by electrical sparks has been found to by cytotoxic to hamster cells when tested in an in vitro cell survival assay, while SF₆ shows no cytotoxic activity. Chemical analysis of spark‐decomposed SF₆ has identified and quantified the following compounds: SOF₂, SO₂F₂, SF₄, SOF₄, SiF₄, SO₂ and HF. Each of these gases, at concentration ranges expected in spark‐decomposed SF₆, were tested for cytotoxic activity toward hamster cells. Of the gases showing cytotoxic activity, SO₂F₂ and SOF₄ were similar in activity, as were SOF₂ and SF₄, while the behavior of SiF₄ was different from the rest. None of these individual gases, at concentrations expected in spark‐decomposed SF₆, has sufficient cytotoxic activity to account for the cytotoxic effect of spark‐decomposed SF₆ observed in our assay system. A four‐component mixture of some of the gases enumerated above (at concentrations overestimating their abundance in spark‐decomposed SF₆) was much less cytotoxic than the spark‐decomposed SF₆ gas. A mathematical simulation of the cytotoxic activity of a mixture of gases at concentrations found in spark‐decomposed SF₆ was made, assuming independent cytotoxic effects from each component. The simulated cytotoxic effect thus computed was less than that seen in spark‐decomposed SF₆. Since individual components or mixtures of the major decomposition products do not account for the observed biological activity of spark‐decomposed SF₆, this suggests there may be one or more components, present in the spark‐decomposed gas at very low concentrations, which may have a very strong cytotoxic activity.     

Adsorptive separation of phosphate oxyanion from aqueous solution using an inorganic adsorbent

Phosphate removal from aqueous solution was explored using granular ferric hydroxide (GFH) as an inorganic adsorbent. Adsorption, desorption and kinetic studies were conducted on laboratory scale to evaluate the performance of GFH as an adsorbent for low concentrations of phosphate solution. The effect of pH on adsorption was investigated, and phosphate uptake was shown to decrease with an increase in solution pH, with maximum removal seen to occur at pH 3. The experimental data best fit the Temkin isotherm at both pH 3 and 4. Uptake of phosphate by GFH follows second-order kinetics, with the small particle range (76–200 μm) removing phosphate from the solution more rapidly than the larger particle range (710–850 μm). The kinetic results suggest that intra-particle diffusion is an important factor in phosphate adsorption onto GFH. Thermodynamic parameters (ΔG°, ΔH°, ΔS°) were evaluated, and the results indicated that the adsorption process was endothermic and spontaneous. This study demonstrates that GFH has potential to be used as a cost-effective adsorbent for phosphate removal from aqueous solution.