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421.
Richard Roth Paul R. Marques Robert B. VoasAuthor vitae 《Journal of Safety Research》2009,40(6):437-441
Introduction
The effectiveness of ignition interlocks at reducing drunk driving has been limited by the ability of driving-while-intoxicated (DWI) offenders to avoid court orders to install the devices.Methods
In a pilot program in New Mexico, four Santa Fe County judges imposed home confinement (via electronic monitoring bracelets) on offenders who claimed to have no car or no intention to drive. Interlock installation rates for Santa Fe County were compared with all other counties in New Mexico over a 2-year program and 2-year post-program period.Results
During the two program years, 70% of the drivers convicted of DWI in Santa Fe County installed interlocks, compared to only 17% in the other counties, but when the program was terminated, the Santa Fe installation rate fell by 18.8 percentage points.Summary
Mandating the alternative sanction of house arrest led to the highest reported interlock installation rate for DWI offenders.Impact on Industry
Impaired driving is a substantial expense to employers, particularly when it bars driving that interferes with employment. Interlocks provide a method of protecting the public while permitting the offender to drive sober. This study was directed at increasing interlock use by DWI offenders. 相似文献422.
Mario C.R. Vidal Paulo V.R. Carvalho Marcello S. Santos Isaac J.L. dos Santos 《Journal of Loss Prevention in the Process Industries》2009,22(4):516-527
This article aims to describe the characteristics of collective working situations in complex systems – especially those in nuclear power plants – related to common forms of cooperation, in order to improve systems resilience. In addition, we will try to detail some aspects of collective working situations, emphasizing the differences between various forms of control. The similarities between work activities (multi-addressed messages, linkage to regulation, central and peripheral information) are nonetheless exposed. We conclude by proposing a contribution to support systems design, thus facilitating cooperation in teamwork activities. 相似文献
423.
424.
Stacey R. Kessler 《组织行为杂志》2019,40(9-10):1046-1054
A definitional component of organizational climate is the focus on employees' shared perceptions of the focal climate domain. To operationalize the notion of sharedness, researchers typically aggregate employees' domain‐specific climate perceptions to a higher level and justify this aggregation using quantitative indices of agreement. In the current paper, I argue that although accounting for sharedness among employees can provide some valuable insight, our overreliance on sharedness obscures some of the very organizational phenomena of interest. I discuss this issue by focusing on four costs of making unfounded assumptions regarding sharedness: (a) Aggregation assumes individual differences are a function of random error; (b) aggregation assumes that social situations are uniform across employees; (c) aggregation assumes that the unit of analysis is clear‐cut; and (d) aggregation assumes the group mean is meaningful. I argue that researchers carefully need to weigh the costs of violating these assumptions against the expected benefits of aggregating employees' climate perceptions, recognizing that sometimes employees' perceptions (i.e., psychological climate) might provide greater insight into phenomena of interest. Although I discuss these costs within the context of organizational climate research, these arguments apply to other research areas where individual perceptions are aggregated (e.g., research on leadership and teams). 相似文献
425.
Methylotrophic bacteria inhabit the surface of plant organs, but the interaction between these microbes and their host cells is largely unknown. Protonemata (gametophytes) of the moss Funaria hygrometrica were cultivated in vitro under axenic conditions and the growth of the protonemal filaments recorded. In the presence of methylobacteria (different strains of Methylobacterium), average cell length and the number of cells per filament were both enhanced. We tested the hypothesis that auxin (indole-3-acetic acid, IAA), secreted by the epiphytic bacteria and taken up by the plant cells, may in part be responsible for this promotion of protonema development. The antiauxin parachlorophenoxyisobutyric acid (PCIB) was used as a tool to analyze the role of IAA and methylobacteria in the regulation of cell growth. In the presence of PCIB, cell elongation and protonema differentiation were both inhibited. This effect was compensated for by the addition of different Methylobacterium strains to the culture medium. Biosynthesis and secretion of IAA by methylobacteria maintained in liquid culture was documented via a colorimetric assay and thin layer chromatography. Our results support the hypothesis that the development of Funaria protonemata is promoted by beneficial phytohormone-producing methylobacteria, which can be classified as phytosymbionts. 相似文献
426.
R. Scaffaro N. Tz. Dintcheva R. Marino F. P. La Mantia 《Journal of Polymers and the Environment》2012,20(2):267-272
In this paper, the processability and the performance of a biodegradable polymer, Mater-Bi, and of its blends with either a sample of poly (hydroxy alkanoates) (PHA) or with bacterial biomass containing PHAs were compared. Adding PHA or directly the biomass containing it allows improving the processability of the matrix. Moreover, the mechanical behaviour of the systems was compared considering two different preparation methods, namely compression and injection moulding. The injection moulded samples show poorer mechanical performances than those of the compression moulded systems. The impact strength significantly improves when PHA is added while it reduces when bacterial biomass is used instead. In this latter case this was likely due to the easier propagation of micro-cracks during the impact tests. 相似文献
427.
A. Chiumenti F. da Borso R. Chiumenti F. Teri P. Segantin 《Waste management (New York, N.Y.)》2013,33(6):1339-1344
Vacuum evaporation consists in the boiling of a liquid substrate at negative pressure, at a temperature lower than typical boiling temperature at atmospheric conditions. Condensed vapor represents the so called condensate, while the remaining substrate represents the concentrate.This technology is derived from other sectors and is mainly dedicated to the recovery of chemicals from industrial by-products, while it has not been widely implemented yet in the field of agricultural digestate treatment. The present paper relates on experimental tests performed in pilot-scale vacuum evaporation plants (0.100 and 0.025 m3), treating filtered digestate (liquid fraction of digestate filtered by a screw-press separator). Digestate was produced by a 1 MWe anaerobic digestion plant fed with swine manure, corn silage and other biomasses. Different system and process configurations were tested (single-stage and two-stage, with and without acidification) with the main objectives of assessing the technical feasibility and of optimizing process parameters for an eventual technology transfer to full scale systems.The inputs and outputs of the process were subject to characterization and mass and nutrients balances were determined.The vacuum evaporation process determined a relevant mass reduction of digestate.The single stage configuration determined the production of a concentrate, still in liquid phase, with a total solid (TS) mean concentration of 15.0%, representing, in terms of mass, 20.2% of the input; the remaining 79.8% was represented by condensate. The introduction of the second stage allowed to obtain a solid concentrate, characterized by a content of TS of 59.0% and representing 5.6% of initial mass.Nitrogen balance was influenced by digestate pH: in order to limit the stripping of ammonia and its transfer to condensate it was necessary to reduce the pH. At pH 5, 97.5% of total nitrogen remained in the concentrate. This product was characterized by very high concentrations of total Kjeldhal nitrogen (TKN), 55,000 mg/kg as average.Condensate, instead, represented 94.4% of input mass, containing 2.5% of TKN. This fraction could be discharged into surface water, after purification to meet the criteria imposed by Italian regulation. Most likely, condensate could be used as dilution water for digestion input, for cleaning floor and surfaces of animal housings or for crop irrigation.The research showed the great effectiveness of the vacuum evaporation process, especially in the two stage configuration with acidification. In fact, the concentration of nutrients in a small volume determines easier transportation and reduction of related management costs. In full scale plants energy consumption is estimated to be 5–8 kWhe/m3 of digestate and 350 kWht/m3 of evaporated water. 相似文献
428.
Tan K Yang MX Radloff SE Hepburn HR Zhang ZY Luo LJ Li H 《Die Naturwissenschaften》2008,95(12):1165-1168
Although the structure of the dance language is very similar among species of honeybees, communication of the distance component
of the message varies both intraspecifically and interspecifically. However, it is not known whether different honeybee species
would attend interspecific waggle dances and, if so, whether they can decipher such dances. Using mixed-species colonies of
Apis cerana and Apis mellifera, we show that, despite internal differences in the structure of the waggle dances of foragers, both species attend, and act
on the information encoded in each other’s waggle dances but with limited accuracy. These observations indicate that direction
and distance communication pre-date speciation in honeybees. 相似文献
429.
Jesús R. Rodríguez-Núñez Tomás J. Madera-Santana Dalia I. Sánchez-Machado Jaime López-Cervantes Herlinda Soto Valdez 《Journal of Polymers and the Environment》2014,22(1):41-51
The addition of plasticizers to biopolymer films is a good method for improving their physicochemical properties. The aim of this study was to evaluate the effect of chitosan (CHI) blended with two hydrophilic plasticizers glycerol (GLY) and sorbitol (SOR), at two concentrations (20 and 40 wt%) on their mechanical, thermal, barrier, structural, morphological and antimicrobial properties. The chitosan was prepared through the alkaline deacetylation of chitin obtained from fermented lactic from shrimp heads. The obtained chitosan had a degree of deacetylation (DA) of 84 ± 2.7 and a molecular weight of 136 kDa, which indicated that a good film had formed. The films composed of CHI and GLY (20 wt%) exhibited the best mechanical properties compared to the neat chitosan film. The percentage of elongation at break increase to over 700 % in the films that contained 40 % GLY, and these films also exhibited the highest values for the water vapor transmission rate (WVTR) of 79.6 ± 1.9 g m2 h?1 and a yellow color (b o = 17.9 ± 2.0) compared to the neat chitosan films (b o = 8.8 ± 0.8). For the structural properties, the Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction analyses revealed an interaction in the acetamide group and changes in the crystallinity of plasticized films. The scanning electron micrographs revealed that all formulations of the chitosan films were smooth, and that they did not contain aggregations, pores or microphase separation. The thermal analysis using differential scanning calorimetry (DSC) revealed a glass transition temperature (Tg) of 130 °C for neat chitosan film, but the addition of SOR or GLY elicited a decrease in the temperature of the peak (120 °C). In addition, the antimicrobial activity of the chitosan films was evaluated against Listeria monocytogenes, and reached a reduction of 2 log after 24 h. The plasticizer concentration of 20 % GLY is sufficient for obtaining flexible chitosan films with good mechanical properties, and it could serve as an alternative as a packaging material to reduce environmental problems associated with synthetic packaging films. 相似文献
430.
Elizabeth Guthrie Nichols Rachel L. Cook James E. Landmeyer Brad Atkinson Donald R. Malone George Shaw Leilani Woods 《补救:环境净化治理成本、技术与工艺杂志》2014,24(2):29-46
A former bulk fuel terminal in North Carolina is a groundwater phytoremediation demonstration site where 3,250 hybrid poplars, willows, and pine trees were planted from 2006 to 2008 over approximately 579,000 L of residual gasoline, diesel, and jet fuel. Since 2011, the groundwater altitude is lower in the area with trees than outside the planted area. Soil‐gas analyses showed a 95 percent mass loss for total petroleum hydrocarbons (TPH) and a 99 percent mass loss for benzene, toluene, ethylbenzene, and xylenes (BTEX). BTEX and methyl tert‐butyl ether concentrations have decreased in groundwater. Interpolations of free‐phase, fuel product gauging data show reduced thicknesses across the site and pooling of fuel product where poplar biomass is greatest. Isolated clusters of tree mortalities have persisted in areas with high TPH and BTEX mass. Toxicity assays showed impaired water use for willows and poplars exposed to the site's fuel product, but Populus survival was higher than the willows or pines on‐site, even in a noncontaminated control area. All four Populus clones survived well at the site. © 2014 Wiley Periodicals, Inc.* 相似文献