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31.
Green River oil shale was supercritically treated with methanol and water and then extracted with benzene and methanol to recover approximately 85% of the organic matter in the shale. The spent shale was then extracted with pyridine to recover an additional 2-31% of the organic matter that remained on the shale. The liquid organic material extracted with pyridine contained some of the compound types most difficult to recover from shale. These materials were characterized. High-molecular nitrogen compounds of the pyridine type were found to be a predominant compound class in the pyridine extract. The pyridine-extracted material contained a higher percentage of nitrogen than a Fischer assay oil and a lower percentage of hydrogen than a Fischer assay oil indicating that more aromatic nitrogen compounds were present in the pyridine extract than in Fischer assay oil. Bonding mechanisms between organic and inorganic components of the shale were studied as were spectroscopic data showing the nature of the organic material remaining on spent shale after extraction with pyridine. 相似文献
32.
Roles of Levies for Sustainable Domestic Water Consumption 总被引:1,自引:1,他引:0
Sustainable development is the modern rhetoric to guide environmental or natural resources management. There are many ways
to do this and one is the wider utilization of economic instruments, such as taxes and levies. Although such levies are becoming
common in Australia and worldwide, the role of the taxes or levies is still limited. In many cases, these taxes/levies -although
environmentally related- have a fiscal rather than a purely environmental motive, for example, the Natural Resources Management
(NRM) Levy in South Australia. This study evaluates the NRM levy policy using one NRM region and focussing on the Adelaide
urban community. Data was collected through a web-based survey with 770 respondents who answered 59 questions. The research
found that community strongly prefers a levy calculated on the volume of water consumed. Respondents also indicated that they
would use less water if the levy were calculated on the volume of water consumed. The clear implications of the results suggest
that if a tax or levy aims to change water consumption behaviour then it should be based on the volume of water consumed not
on property value. 相似文献
33.
Mensinger Janell Lynn; Lynch Kevin G.; TenHave Thomas R.; McKay James R. 《Canadian Metallurgical Quarterly》2007,75(5):775
A previous randomized trial with 224 alcohol and/or cocaine addicts who had completed an initial phase of treatment indicated that 12 weeks of telephone-based continuing care yielded higher abstinence rates over 24 months than did group counseling continuing care. The current study examined mediators of this treatment effect. Results suggested that self-help involvement during treatment and self-efficacy and commitment to abstinence 3 months after treatment mediated subsequent abstinence outcomes. These analyses controlled for substance use prior to the assessment of mediators. Conversely, there was no evidence that self-help beliefs or social support mediated the treatment effect. These results are consistent with a model in which treatment effects are first accounted for by changes in behavior, followed by changes in self-efficacy and in commitment to abstinence. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
34.
35.
A M McKay 《International journal of food microbiology》1992,15(3-4):383-388
Permeation of oxygen through polystyrene packaging is a factor in the growth of yeasts in natural yoghurt. Diffusion of oxygen through the packaging material can permit the growth of non-fermentative yeasts in yoghurt stored at refrigeration temperatures. Yarrowia lipolytica, a non-fermentative yeasts which does not utilize lactose was isolated from yoghurt. The growth in natural yoghurt of Yarrowia lipolytica and the lactose-fermenting yeast Kluyveromyces marxianus was investigated. Both yeasts grew in yoghurt with reduced fat content. Storage of yoghurt in an anaerobic atmosphere eliminated growth of Yarrowia lipolytica but permitted fermentative growth of Kluyveromyces marxianus. 相似文献
36.
Lash Steven J.; Timko Christine; Curran Geoffery M.; McKay James R.; Burden Jennifer L. 《Canadian Metallurgical Quarterly》2011,25(2):238
Continuing care following initial substance use disorder treatment often is associated with improved treatment outcomes and evidence-based interventions (EBIs) have been developed in this area. However, rates of patient participation in continuing care treatment and mutual help groups (MHGs) are low and a large gap exists between the existing EBIs and actual clinical care. This paper uses the Consolidated Framework for Implementation Research (CFIR; Damschroder et al., 2009) to review the literature on continuing care treatment and monitoring, and mutual help-group promotion. Although existing research provides implications for implementing EBIs in continuing care, few direct implementation trials have been conducted. This literature indicates that EBIs in continuing care have been successfully modified for different settings, that they can be delivered using different modalities (e.g., individual, group, and telephone-based care), and that low cost options are available. Additionally, much is known about the differential effectiveness of continuing care with different populations that may guide treatment programs and providers in selecting the most effective interventions for their clients. One significant barrier to successful implementation of EBIs for continuing care is the lack of information about incentives for providing continuing care across what in the CFIR terminology is a program's outer setting (i.e., external economic, political, and social setting), and its inner setting (i.e., internal political, structural, and cultural contexts). Implications for implementation of EBIs in substance use disorder continuing care are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
37.
Superantigens (SAgs) are extremely potent stimulants of T cell activity that have been implicated in the etiopathophysiology of inflammatory disease. Here, we tested the hypothesis that Staphylococcus aureus enterotoxin B (SEB), a model SAg, can alter epithelial transport and/or barrier functions via immune stimulation. Confluent monolayers of the human colonic T84 epithelial cell line, grown on filter supports, were cocultured with SEB +/- PBMC. Subsequently, T84 transport (consisting of baseline short-circuit current (Isc, indicates net ion transport) and secretory responses to carbachol and forskolin) and barrier functions (consisting of transepithelial resistance and fluxes of 3H-labeled mannitol and 51Cr-EDTA) were examined in Ussing chambers. T84 monolayers cocultured with SEB-activated PBMC displayed a time- and dose-dependent decrease in secretory responses to carbachol and forskolin and a significant increase in permeability. These dramatic changes in epithelial function were not due to reduced epithelial viability. Neutralizing Abs to IFN-gamma partially prevented the transport abnormalities, and Abs to TNF-alpha inhibited the increase in epithelial permeability. Abs to IL-1beta and IL-6 did not modulate the SEB-activated PBMC-induced T84 pathophysiology. Addition of TGF-beta2 to conditioned medium from SEB-activated PBMC partially inhibited the increase in T84 permeability but did not affect the transport abnormalities. We conclude that SAgs can elicit epithelial irregularities characteristic of enteric inflammation and that IFN-gamma and TNF-alpha are key mediators in this coculture model of epithelial dysfunction. Additionally, we would highlight the role that TGF-beta2 may play in preventing prolonged increases in epithelial permeability. 相似文献
38.
39.
Schedulers' decisions in real factories deal with perceived risks and impacts. They proactively anticipate and reactively mitigate risky events by altering what would be considered a normal schedule to minimize associated impacts. These risk mitigation concepts are called aversion dynamics (AD). Aversion dynamics describes the aversion that jobs exhibit to impacts resulting from risky events in dynamic and unstable production environments. The aversion manifests itself in either advancing or delaying the work to avoid the risky period. This paper extends the first AD heuristic, Averse-1, to capture additional real-world dynamics and to make the heuristic predictive (proactive) as to when the perceived risky event may happen. In particular, predictive and stochastic elements are incorporated within a dynamic job arrival framework to create an extended heuristic called Averse-2. 相似文献
40.
Fluorescent in situ hybridisation (FISH) is a powerful tool for the evaluation of chromosomal alterations in formalin fixed paraffin wax embedded sections of colorectal cancer. However, initial experiments using a two-step detection system for digoxigenin labelled chromosome specific centromeric probes resulted in a complete lack of hybridisation signal from a number of colorectal tumour sections. This was due to high levels of background autofluorescence observed in this tissue, which masked any relatively weak hybridisations present. To overcome this problem, a biotinylated tyramide mediated amplification system was incorporated into the FISH detection protocol. This involves the use of horseradish peroxidase to activate the biotinylated tyramide, resulting in the deposition of a large number of biotin molecules at the site of bound peroxidase, which corresponds directly to the location of hybridised probe. Final detection was by means of a streptavidin-FITC conjugate. Using this technique, a panel of 11 colorectal tumour samples studied to date have shown strong, specific hybridisation signals to the nucleus of tumour cells. Amplification of FISH signals by biotinylated tyramide has the potential to improve weak hybridisation signals in cells from numerous sources, using a variety of probe types, including single copy gene probes as well as centromere specific probes. 相似文献