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1.
Saccharomyces cerevisiae was cultivated in the presence of cis-9,trans-11 or trans-10,cis-12 isomers of free conjugated linoleic acid (CLA), and the effects of the isomers on the regioisomerisms of triacylglycerol (TAG) of the yeast were elucidated. Both isomers constituted about 34% of all fatty acids and increased drastically the number of different TAG species. Nearly all of the species contained CLA in at least one sn-position. In the most abundant species analyzed (20% of total species), the cis-9,trans-11 isomer appeared in combination with monounsaturated fatty acids (C16:1, C:18:1) whereas trans-10,cis-12 isomer was most frequently present with a medium chain fatty acid (C10:0 or C12:0) in the sn-2 position and C16:0 in one of the end positions (14% of total species). With either isomer, the amount of TAG species in which CLA encompassed all sn-positions was ca. 4%. Thus, S. cerevisiae can be used to produce edible single cell oil characterized by very heterogeneous distribution of CLA among the different TAG species.  相似文献   
2.
A microbially safe process for the enrichment of conjugated linoleic acid (CLA) in oats was developed. The process consists of hydrolysis of oat lipids by non-inactivated oat flour, followed by propionibacterium-catalyzed isomerization of the resulting free linoleic acid to CLA. The first stage was performed at water activity (a(w)) 0.7, where hydrolysis of triacylglycerols progressed efficiently without growth of the indigenous microflora of flour. Thereafter, the flour was incubated as a 5% (w/v) aqueous, sterilized slurry with Propionibacterium freudenreichii ssp. shermanii. The amount of CLA produced in 20 h was 11.5 mg/g dry matter corresponding to 116 mg/g lipids or 0.57 mg/mL slurry. The oat flour had also the capability to hydrolyze exogenous oils at a(w) 0.7. Sunflower oil, added to increase linoleic acid content in triacylglycerols 2.7-fold, was hydrolyzed rapidly. Isomerization of this oil-supplemented flour as a 5% slurry gave final CLA content of 22.3 mg/g dry matter after 50 h of fermentation, corresponding to 118 mg/g lipids or 1.14 mg/mL slurry. Storage stability of CLA in fermented oat slurries at 4 degrees C was good.  相似文献   
3.
Total gaseous mercury (TGM) fluxes from the forest floor and a boreal wetland were measured by a flux chamber technique coupled with an automatic mercury vapour analyser. The fluxes were measured at three sampling sites in southern Finland, 61°14′ N, 25°04′ E in summer 2007, with additionally in situ TGM concentrations in the air at one of the sites and mercury bulk deposition at another. Most of the flux data were collected during the daytime. At one of the sites, diurnal flux behaviour was studied, and a clear cycle with an afternoon maximum and a night minimum was observed. The highest emissions (up to 3.5 ng m−2 h−1) were observed at the forest floor site having a moss and grass cover. At the wetland and litter-rich forest floor sites, the emissions were below 1 ng m−2 h−1 and sometimes negative (down to −1.0 ng m−2 h−1), indicating mercury uptake. The measured average fluxes in August were 0.9 ± 1.1 and 0.2 ± 0.3 ng m−2 h−1 for the forest floor sites and wetland sites, respectively. The flux data were compared with the mercury bulk deposition, which proved to be of the same magnitude, but opposite in sign. At the mossy forest floor site, the extrapolated TGM emissions were 130% of the Hg deposition in August 2007. Comparison with other studies showed that the fluxes in background areas are relatively uniform, regardless of measurement site location and method used. Airborne TGM remained at the background level during the study, with an average value of 1.3 ± 0.2 ng m−3; it frequently showed a diurnal cycle pattern.  相似文献   
4.

Tuning participatory processes is often insufficient to achieve transition from authoritative state to democratic and participatory forest governance due to institutional inertia and unwillingness to truly decentralize decision-making power. Social innovations as reconfigurations of relationships between state, market actors, civil society and science can help to meet concerns of local people about forest Ecosystem Services (ES). In Ukraine, the Swiss-Ukrainian Forest Development (FORZA) pilot project initiated a social innovation process complementing regional forest planning with local participatory community development plans in Transcarpathia. This paper examines what kind of changes need to accompany the succession of participatory practices in transition processes from authoritative state to democratic forest governance, and what are the lessons learned for social innovations based on the Ukrainian case study. This paper synthesizes knowledge on the FORZA case analyzed by inductive content analysis, and integrates these local level results with a national survey (N?=?244) on Ukrainian forest governance. Transition processes need to go “beyond participation” by (i) legal reforms to better acknowledge ES important for local people, (ii) a change from an exclusive focus on timber to acknowledging multiple ES, (iii) changed spatial and temporal rationales of state-based governance, and (iv) recognition of local people as credible experts. Social innovations can detect key barriers to the transition during the policy experiments, and need to pay significant attention on how the novel practices can be sustained after the pilot, replicated elsewhere and up-scaled. Without such considerations, social innovation projects may only remain as a marginal curiosity.

  相似文献   
5.
Since the UNCED in 1992, National Forest Programmes (NFP) have been widely acknowledged as a means to implement internationally agreed upon sustainability goals for forest management. However, national forest programmes are prepared and implemented in national political, social and ecological contexts, which vary significantly between countries. Finland has a long tradition of “forest programming”, starting from the 1950s, which has contributed to the institutions and culture of preparing such programmes. These programmes have traditionally been prepared in governmentally facilitated committees and working groups in close collaboration with interest groups and representatives of research and administration.In this paper, we develop goals for participation in a policy decision-making process. These goals, based on sustainable development definitions and policies, include: (1) generating new relevant information, (2) incorporating all relevant interests, and (3) contributing to reaching public agreement.Demands for increasing public awareness, inclusion of different views as well as respect for procedural citizen rights were obvious expectations also behind Finland's National Forest Programme 2010 that was made in 1999. The new forms of participation applied in the already well-developed interest-group-integrating policy preparation system provided an opportunity to take the participation goals more seriously. According to our analysis, the arguments arising from the new forms of participation were strongly in line with those already previously present in Finnish forest policy discourse, and the new forms of participation functioned merely as legitimating and awareness raising systems.  相似文献   
6.
Fisheries management aims to ensure that the fishing activities are environmentally sustainable in the long term, while also achieving the economic, social and food security related management objectives. To facilitate this, both the ecological and human dimensions of sustainability need to be included in fisheries assessment. In addition, assessing long‐term sustainability calls for taking into account plausible changes in the surrounding societal conditions that shape the characteristics of the fisheries governance system, as well as the ecological conditions. The paper uses a combination of qualitative exploratory scenario storylines (ESS) and Bayesian belief networks (BBN) to integrate the environmental, economic, social and food security dimensions in an interdisciplinary assessment of the future sustainability of Baltic herring (Clupea harengus membras, Clupeidae) and salmon (Salmo salar, Salmonidae) fisheries. First, four alternative ESS were created based on plausible changes in societal drivers. The ESS were then formulated into a BBN to (a) visualize the assumed causalities, and (b) examine quantitatively how changes in the societal drivers affect the social‐ecological fisheries system and ultimately the fisheries management objectives. This type of probabilistic scenario synthesis can help in thinking qualitative scenarios in a quantitative way. Moreover, it can increase understanding on the causal links between societal driving forces and the complex fisheries system and on how the management objectives can be achieved, thereby providing valuable information for strategic decision‐making under uncertainty.  相似文献   
7.
We tested here a plant-soil system to separate recent, plant-derived and native, soil-derived carbon in soil respiration. The approach uses a perennial crop cultivated on an organic soil where upper soil layers have been removed as a result of peat extraction. There, the 14C signal from native organic matter is highly depleted compared to that in vegetation established at the site after peat extraction ceased. Radiocarbon was analyzed in carbon dioxide respired from soil over one growing season, and a two-pool isotope mixing model was applied to calculate the relative contribution of old vs. new carbon sources. The analysis showed that the approach is reliable for source partitioning with isotopes. After six years of cultivation, old peat decomposition contributed less to total soil respiration than respiration of recent plant material (30% vs. 70% on average, respectively), but the relative proportions were highly variable over the growing season. The approach offers a new possibility to follow the fate of old, native soil organic matter in highly organic soils.  相似文献   
8.
9.
A method for microbial isomerization of oat linoleic acid to conjugated linoleic acid (CLA) was developed. The method includes hydrolysis of oat lipids in aqueous flour slurries by the endogenous oat lipase. Then, the flour slurry containing free linoleic acid is utilized as a substrate for the isomerization reaction carried out by resting cells of Propionibacterium freudenreichii ssp. shermanii. The isomerization reaction progressed most effectively when, after the lipid hydrolysis period, the pH of the slightly acidic oat slurry was elevated to 8.0-8.5 and maintained at this range. With slurries containing 5% (w/v) oat flour, the amounts of CLA formed per dry matter were up to 10.1 mg/g corresponding to 102 mg/g lipids or 0.44 mg/mL slurry. Increments in the flour content up to 15% increased the volumetric production of CLA to 0.85 mg/mL. The proportion of the cis-9,trans-11 isomer was 80% of the total CLA formed. CLA could be concentrated into the solid material of the oat slurry by acidification.  相似文献   
10.
The aim of the study was to examine how the thickness and species of softwood influence cupping during cyclic conditions. The study was conducted with full-scale test walls in laboratory conditions. On the basis of the results, the thickness and species of softwood both have a significant influence on cupping of the cladding board. The boards made of Norway spruce were considerably more resistant to cupping than those made of Scots pine sapwood. Boards made of Scots pine sapwood were more likely to remain curved after each drying period. It appears probable that the cupping sensitivity of Scots pine sapwood affects the durability of the cladding, e.g., causing cracking formation on the surface and peeling of the coating. From the curving results, it is possible to estimate surface elongation and durability of the wood surface and of the coating in cyclic conditions.  相似文献   
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