How drivers decide whether to get a fuel cell vehicle: An ethnographic decision model

This article develops and tests an ethnographic decision model (EDM) of hydrogen fuel cell vehicle (FCV) adoption using interviews with California residents that either actually adopted an FCV or “seriously considered” doing so before deciding against it. We developed an initial model from 25 semi-structured interviews in which respondents self-described their decision-making processes. We iteratively tested and refined the model in a second round of 53 structured interviews. The final model consists of a first stage that assesses FCV adoption feasibility and a second stage that compares FCVs to other vehicle types. The model ultimately correctly predicts 86.8% of cases in the sample. In the first stage, respondents preferred to satisfy their need for a primary refueling station near home but a substantial number were willing to rely on a station near or on the way to work or other destination. Most drivers required a convenient backup station and a means of managing long-distance trips. Vehicle size options eliminated a few respondents. None rejected FCV adoption due to insufficient driving range. In the second stage, nearly all drivers engaged in some kind of cost comparison, though the factors considered varied greatly. Most opted for what they viewed as the less costly option, although a few FCV adopters and non-adopters were willing to pay more for their more preferred option. EDM is a promising qualitative research method for generating insights into how people navigate the decision whether or not to get an alternative-fuel vehicle.     

Contingency management and levodopa-carbidopa for cocaine treatment: A comparison of three behavioral targets.

New data support use of levodopa pharmacotherapy with behavioral contingency management (CM) as one efficacious combination in cocaine dependence disorder treatment. A potential mechanism of the combined treatment effects may be related to dopamine-induced enhancement of the saliency of contingently delivered reinforcers. Evidence to support this mechanism was sought by evaluating levodopa-enhancing effects across distinct CM conditions that varied in behavioral targets. A total of 136 treatment-seeking, cocaine dependent subjects participated in this 12-week, randomized, placebo-controlled trial of levodopa (vs. placebo) administered in combination with one of three behavioral CM conditions. In the CM-URINE condition, subjects received cash-valued vouchers contingent on cocaine-negative urine toxicology results. In the CM-ATTEND condition, the same voucher schedule was contingent on attending thrice weekly clinic visits. In the CM-MEDICATION condition, the same voucher schedule was contingent on Medication Event Monitoring Systems- and riboflavin-based evidence of pill-taking behavior. Primary outcomes associated with each CM target behavior were analyzed using generalized linear mixed models for repeated outcomes. CM responding in the CM-ATTEND and CM-MEDICATION conditions showed orderly effects, with each condition producing corresponding changes in targeted behaviors, regardless of medication condition. In contrast, CM responding in the CM-URINE condition was moderated by medication, with levodopa-treated subjects more likely to submit cocaine-negative urines. These findings specify the optimal target behavior for CM when used in combination with levodopa pharmacotherapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Postpartum return to smoking: Staging a "suspended" behavior.

Two hundred fifty-six pregnant women who had quit smoking were classified into the precontemplation (PC), contemplation (C), preparation (PA), or action (A) stages of change for postpartum smoking cessation based on a 3-item algorithm assessing personal goals, self-efficacy, and smoking behavior. Logistic regression and event history analyses indicated group differences in return to smoking at 6 weeks and 3, 6, and 12 months postpartum. The percentage of women who returned to postpartum smoking was highest in the precontemplation stage and decreased with each subsequent stage, that is, at 6 weeks 83% of PCs, 64% of Cs, 35% of PAs, and 24% of As had returned to smoking. Results lend support for the stages of change for postpartum smoking abstinence. Stage-based interventions may be developed to assist women in maintaining abstinence postpartum. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Acoustic Emission in Composite Laminates

The response of a laminated plate to internal acoustic emission events is examined in detail. The plate consists of four layers of a unidirectional fiber composite material arranged in a cross-ply configuration. The sources considered include a vertical line couple, a horizontal line couple and a line double couple without moment. The latter is produced by the combination of two equal and opposite line couples and may be associated with a shear dislocation in the plane of the laminate. The particular response presented here is that of the normal upper surface displacement. Four different orientations of the line sources relative to the core fiber direction are considered. The sources may be located at any depth within the plate and results are shown for three locations, namely, the upper interface, the midplane and the lower interface. The receiver is positioned on the upper surface at a known distance from the line of action of the source. When this distance is small relative to the depth of the plate, it is possible to associate some of the peaks and troughs present in the response with the arrival of individual rays. At larger distances, the disturbance arises from the propagating Rayleigh Lamb modes.     

Posttreatment with eicosatetraynoic acid decreases lung edema in guinea pigs exposed to phosgene: the role of leukotrienes

Acetylenic acids such as 5,8,11,14-eicosatetraynoic acid (ETYA), have been shown to be effective in preventing pulmonary edema formation (PEF). In phosgene-exposed guinea pigs, we examined the effects of ETYA on PEF, measured as real time lung weight gain (lwg). Pulmonary artery pressure (Ppa), airway pressure (Paw), perfusate leukotrienes (LT) C4/D4/E4/B4, and lung tissue lipid peroxidation (TBARS) were measured using the isolated, buffer-perfused lung model. Guinea pigs were challenged to 175 mg/m3 (44 ppm) phosgene for 10 minutes giving a concentration x time product of 1750 mg.min/m3 (437 ppm.min). Five minutes after removal from the exposure chamber, guinea pigs were treated, i.p., with 200 microL of 100 microM ETYA. 200 microL of 50 microM ETYA was added to the perfusate every 40 minutes, beginning at 60 minutes after start of exposure (t = 0). There were four groups in this study: air-treated, phosgene-exposed, ETYA-posttreated + phosgene, and ETYA-posttreated + air ETYA-posttreated + phosgene guinea pigs had significantly lower Ppa (P = .006), Paw (P = .009), and lwg (P = .016) compared with phosgene-exposed animals. Phosgene exposure reduced LTB4 compared with air-treated controls (P = .09). ETYA-posttreatment + phosgene had significantly increased perfusate LTB4 (P = .0006) compared with phosgene exposure only group. Total perfusate, LTC4 + LTD4 + LTE4, was not different between phosgene-exposed, air-treated or ETYA-posttreatment + phosgene over time. Posttreatment with ETYA significantly lowered TBARS formation, 206 +/- 13 versus 285 +/- 23 nmol/mg protein (P = .016), compared with phosgene-exposed lungs. Paradoxically, ETYA posttreatment decreased PEF and lipid peroxidation, but increased sulfidopeptide LT release from the lung during perfusion. We conclude that LTC4/D4/E4, and B4, may play different roles than previously thought for PEF in the isolated perfused lung model.     

Distribution of tritiated dihydromicrocystin in swine

The distribution of tritiated dihydromicrocystin [3H]2H-MCLR was studied in anesthetized specific-pathogen-free pigs. Two doses were administered i.m. and one dose was given via an isolated ileal loop. At 4 hr after i.v. administration of the toxin at 25 micrograms/kg, 64.6% of the total dose (%TD) was located in the liver, with smaller amounts distributed to the kidneys (1.2% TD), lungs (1.75% TD), heart (0.22% TD), ileum (0.13% TD) and spleen (0.04% TD). A similar distribution was found at 4 hr postdosing in pigs given 75 micrograms/kg, although the liver contained a lower fraction of the total dose, at 46.99% TD, and the kidneys had somewhat more, at 2.19% TD, than the low dose. At the high dose, the fractions of the amount given accounted for by the lungs (0.55% TD), heart (0.23% TD), ileum (0.20% TD) and spleen (0.07% TD) were similar to those at the low dose. The livers of the pigs given 75 micrograms/kg via the ileal loop, at 5 hr postdosing, contained 49.5% TD and the ileum had 33.94% TD. Smaller amounts were distributed to kidneys (1.04% TD), lungs (0.65% TD), heart (0.81% TD) and spleen (0.16% TD). The livers of both groups dosed at 75 micrograms/kg contained higher concentrations of toxin, but lower percentages of the total dose, than the livers of pigs dosed at 25 micrograms/kg. Larger increases in serum arginase in the two 75 micrograms/kg groups were associated with histological evidence of more severe liver damage than at the 25 micrograms/kg dose. Analysis of radiolabeled compounds from hepatic tissue using fast atom bombardment mass spectrometry determined that the primary constituent was [3H]2H-MCLR, but two minor radioactive components were also isolated. These findings indicate that [3H]2H-MCLR is rapidly concentrated in the liver of swine, whether given i.v. or via an isolated ileal loop, that at extremely toxic doses uptake is slowed, and that it is as toxicologically active as the parent compound.     

Sky-radiance gradient measurements at narrow bands in the visible

Accurate calibrated measurements of the radiance of the daytime sky were made in narrow bands in the visible portion of the spectrum. These measurements were made over several months and were tabulated in a sun-referenced coordinate system. The radiance as a function of wavelength at angles ranging from 5 to 90 deg was plotted. A best-fit inverse power-law fit shows inversely linear behavior of the radiance versus wavelength near the Sun (5 deg) and a slope approaching inverse fourth power far from the Sun (60 deg). This behavior fits a Mie-scattering interpretation near the Sun and a Rayleigh-scattering interpretation away from the Sun. The results are also compared with LOWTRAN models.     

SIMULATION AND COMPARISON OF PASSIVE SOLAR HEATING SYSTEMS

A computer model was developed to simulate direct gain, indirect gain, isolated gain and natural passive solar heating systems. The simulation sales were verified using test data from the passive test cells at the National Center for Appropriate Technology. A 139 m² home with standard insulation levels was used lo compare the different passive solar healing techniques. Collector area and storage mass were identified for the direct gain, indirect gain and isolated gain. The natural passive system, which incorporates only south-facing windows for collector area and the mass of the house for storage, used several total window areas on the south side, the maximum of which was approximately 50 percent of the collector area for the other passive heating methods. Inside air temperatures and make-up energy requirements were compared for several different weather patterns.