Safety impacts due to the incompatibility of SUVs, minivans, and pickup trucks in two-vehicle collisions

This research sets out to estimate the effects of vehicle incompatibility on the risk of death or major injury to drivers involved in two-vehicle collisions.Based on data for 2,999,395 drivers, logistic regression was used to model the risk of driver death or major injury (defined has being hospitalized). Our analyses show that pickup trucks, minivans and sport utility vehicles (SUVs) are more aggressive than cars for the driver of the other vehicle and more protective for their own drivers. The effect of the pickups is more pronounced in terms of aggressivity. The point estimates are comparable to those in the Toy and Hammitt study [Toy, E.L., Hammitt, J.K., 2003. Safety impacts of SUVs, minivans, and pickup trucks in two-vehicle crashes. Risk Analysis 23, 641–650], but, in contrast to that study, we are now able to establish that a greater number of these effects are statistically significant with a larger sample size.Like vehicle mass and type, other characteristics of drivers and the circumstances of the collision influence the driver’s condition after impact. Male drivers, older drivers, drivers who are not wearing safety belts, collisions occurring in a higher speed zone and head-on collisions significantly increase the risk of death. Except for the driver’s sex, all of these categories are also associated with an increased risk of death or of being hospitalized after being involved in a two-vehicle collision. For this risk, a significant increase is associated with female drivers.     

Geothermal contribution to greenhouse heating

Plant freezing and plant-growth inhibition are among the major problems in greenhouse cultivation in the central part of Argentina. The possibility of using a constant temperature underground geothermal water source, which flows naturally, has been studied as an economic option to solve these problems. A system of heating by means of geothermal energy, with energy-conservation measures, was designed and evaluated for typical production greenhouses in the southern part of Córdoba, Argentina. The results of tests carried out during 3 years are presented. These results are really promising, taking into account the high benefit/cost relation of the design and the availability of similar geothermal resources in many farms of this region.     

Determination of the adequate minimum model complexity required in anaerobic bioprocesses using experimental data

BACKGROUND: Modelling of anaerobic bioprocesses requires adequate conciliation between model accuracy and complexity. Anaerobic digestion is a highly complex biocatalysed process in which organic (waste) materials are converted into biogas. Complex mathematical models of the process can be difficult to manage, while too simplistic models may be insufficient for specific applications. RESULTS: A technique based on principal component analysis (PCA) is presented to assess the most adequate complexity in anaerobic bioprocess models using preliminary data. The technique is applied to experimental data from a continuously operated pilot‐scale anaerobic digestion process treating diluted wine and to process simulation data generated by a highly complex model (ADM1). The results obtained suggest that models incorporating only four reactions can describe most of the experimental data variability. Similarly, a simplification of the highly complex modified ADM1 used to a four‐reaction model could attain equivalent simulation accuracy. A set of possible four‐reaction networks was evaluated using the PCA information and a best candidate network of reactions is obtained. CONCLUSION: The developed PCA‐based tool allows for the assessment of the adequate complexity in mathematical models of anaerobic digestion of ethanol, a process that appears describable with a high level of accuracy by considering only four biological reactions. Copyright © 2008 Society of Chemical Industry     

Rat bile as a convenient source of secretory IgA and free secretory component

Rat hepatic bile contains three proteins as major constituents: secretory IgA (SIgA), free secretory component (FSC) and albumin. Traces of alpha-macroglobulin, transferrin, IgG and IgM are also detectable. The bile duct daily pours between 5-12 mg each of SIgA and FSC into the rat duodenum. The origin and function of these proteins in bile may represent important clues in the understanding of the SIgA system.     

Biodegradation of a polymeric dye in a pulsed bed bioreactor by immobilised phanerochaete chrysosporium

An immobilised fungal bioreactor operated with pulsation of the gas-phase is proposed and operated at variable conditions for the continuous biological degradation of complex structures. In order to test the system, a hardly biodegradable dye (Poly R-478) was selected as a model compound and Phanerochaete chrysosporium as the ligninolytic fungus. High percentages of decolourisation--between 65% and 80%--under optimal conditions were achieved. Moreover, the system proved to have high stability with long operational periods (at least, 90 days). During the operation Manganese Peroxidase was the sole ligninolytic enzyme detected which points out this enzyme as the main substance responsible for decolourisation. The optimal conditions established were the following: temperature of 37 degrees C, use of oxygen, Mn2+ concentrations between 33 and 330 microM and exogenous H2O2 added in periodical pulses (as chemical reagent, 1 microM or as H2O2 enzymatically generated by 0.6 U L(-1) glucose oxidase and residual glucose).     

A buffer value index to evaluate effects of buffers on ruminal milieu in cows fed high or low concentrate, silage, or hay diets.

Our objective was to develop a buffer value index that would incorporate alterations in both ruminal fluid pH and buffering capacity as indicators of the influence of dietary buffering and alkalinizing agents on ruminal acid-base status. This index was evaluated using ruminal fluid from four lactating Holstein cows fed either sorghum silage or alfalfa hay in high or low concentrate diets. Ruminal fluid was incubated in vitro for 1, 2, 3, 4, or 5 h with no buffer or with 7.1 g of either NaHCO3, sodium sesquicarbonate, or a multielement buffer added per liter of ruminal fluid. Ruminal fluid pH was lower for diets based on high concentrate or alfalfa; buffering capacity between pH 5 and 7 was greater for high concentrate diets but was not affected by forage type. Ruminal fluid pH was higher for sesquicarbonate than for NaHCO3, the multielement buffer, or the control; however, ruminal fluid H+ concentration was similar between sesquicarbonate and NaHCO3, and both were lower than for the multielement buffer. Hydrogen ion concentration for the multielement buffer was lower than for the control. Buffering capacity was highest for NaHCO3, followed by sesquicarbonate, the multielement buffer, and the control. The buffer value index, which accounted for alterations in both H+ concentration and buffering capacity, was highest for NaCHO3, followed by sesquicarbonate, the multielement buffer, and the control. The poor response to the multielement buffer may be attributable to our relatively short incubation interval (less than 5 h). Dietary buffers increase both ruminal fluid pH and buffering capacity; both of these responses are beneficial.(ABSTRACT TRUNCATED AT 250 WORDS)