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121.
Within the EFORWOOD project, new methodological approaches to assess the sustainability impacts of forestry-wood chains (FWC) were developed by using indicators of environmental, social and economic relevance. This paper introduces and discusses the developed approach and the two main products developed in the EFORWOOD project: the Database Client and the Tool for Sustainability Impact Assessment (ToSIA), which hold, calculate and integrate the extensive information and data collected. Sustainability impact assessment (SIA) of FWCs is based on measuring and analysing environmental, economic and social indicators for all of the production processes along the value chain. The adoption of the method varies between applications and depends on the specification of the FWC in the assessment and what questions are studied. ToSIA is very flexible and can apply forest-, product-, industry- and consumer-defined perspectives. Each perspective influences the focus of the analysis and affects system boundaries. ToSIA can assess forest value chains in different geographical regions covering local, regional, national and up to the continental scale. Potential issues and scenarios can be analysed with the tool including, for example, the impacts of different forest policies on the sustainability of an FWC. This paper presents how ToSIA can be applied to solve such diverse problems and underlines this with examples from different case studies. Differences in chain set-up, system boundaries and data requirements are highlighted and experiences with the implementation of the sustainability impact assessment methods are discussed. The EFORWOOD case studies offer valuable reference data for future sustainability assessments.  相似文献   
122.
Six new triterpene tetra-, penta- and hexaosides, chitonoidosides A (1), A1 (2), B (3), C (4), D (5), and E (6), containing one or two sulfate groups, have been isolated from the Far-Eastern sea cucumber Psolus chitonoides, collected near Bering Island (Commander Islands) from the depth of 100–150 m. Three of the isolated compounds (1, 3 and 6) are characterized by the unusual aglycone of new type having 18(20)-ether bond and lacking a lactone in contrast with wide spread holostane derivatives. Another unexpected finding is 3-O-methylxylose residue as a terminal unit in the carbohydrate chains of chitonoidosides B (3), C (4), and E (6), which has never been found before in the glycosides from holothurians belonging to the Psolidae family. Moreover, this monosaccharide is sulfated in the compound 4 into unprecedented 3-O-methylxylose 4-O-sulfate residue. Chitonoidoside C (4) is characterized by tetrasaccharide moiety lacking a part of the bottom semi-chain, but having disaccharide fragment attached to C-4 of Xyl1. Such architecture is not common in sea cucumber glycosides. Cytotoxic activities of the compounds 1–5 against mouse and human erythrocytes and human cancer cell lines: adenocarcinoma HeLa, colorectal adenocarcinoma DLD-1, and leukemia promyeloblast HL-60 cells were studied. The cytotoxic effect of chitonoidoside d (5) was the most significant in this series due to the presence of pentasaccharide disulfated sugar chain in combination with holostane aglycone. Surprisingly, the glycosides 1 and 3, comprising the new aglycone without γ-lactone, demonstrated similar activity to the known compounds with holostane aglycones. Chitonoidoside C (4) was less cytotoxic due to the different architecture of the carbohydrate chain compared to the other glycosides and probably due to the presence of a sulfate group at C-4 in 3-O-MeXyl4.  相似文献   
123.
A new strain belonging to the genus Collimonas was isolated from the sea surface microlayer off the coast of Trøndelag, Norway. The bacterium, designated Collimonas CT, produced an antibacterial compound active against Micrococcus luteus. Subsequent studies using LC-MS identified this antibacterial compound as violacein, known to be produced by several marine-derived bacteria. Fragments of the violacein biosynthesis genes vioA and vioB were amplified by PCR from the Collimonas CT genome and sequenced. Phylogenetic analysis of these sequences demonstrated close relatedness of the Collimonas CT violacein biosynthetic gene cluster to those in Janthinobacterium lividum and Duganella sp., suggesting relatively recent horizontal gene transfer. Considering diverse biological activities of violacein, Collimonas CT shall be further studied as a potential producer of this compound.  相似文献   
124.
The marine environment represents a largely untapped source for isolation of new microorganisms with potential to produce biologically active secondary metabolites. Among such microorganisms, Gram-positive actinomycete bacteria are of special interest, since they are known to produce chemically diverse compounds with a wide range of biological activities. We have set out to isolate and characterize actinomycete bacteria from the sediments in one of the largest Norwegian fjords, the Trondheim fjord, with respect to diversity and antibiotic-producing potential. Approximately 3,200 actinomycete bacteria were isolated using four different agar media from the sediment samples collected at different locations and depths (4.5 to 450 m). Grouping of the isolates first according to the morphology followed by characterization of isolates chosen as group representatives by molecular taxonomy revealed that Micromonospora was the dominating actinomycete genus isolated from the sediments. The deep water sediments contained a higher relative amount of Micromonospora compared to the shallow water samples. Nine percent of the isolates clearly required sea water for normal growth, suggesting that these strains represent obligate marine organisms. Extensive screening of the extracts from all collected isolates for antibacterial and antifungal activities revealed strong antibiotic-producing potential among them. The latter implies that actinomycetes from marine sediments in Norwegian fjords can be potential sources for the discovery of novel anti-infective agents.  相似文献   
125.
Quantifying species turnover is an important aspect of biodiversity monitoring. Turnover measures are usually based on species presence/absence data, reflecting the rate at which species are replaced. However, measures that reflect the rate at which individuals of a species are replaced by individuals of another species are far more sensitive to change. In this paper, we propose families of turnover measures that reflect changes in species proportions. We study the properties of our measures, and use simulation to assess their success in detecting turnover. Using data on the British farmland bird community from the breeding bird survey, we evaluate our measures to quantify temporal turnover and how it varies across the British mainland.  相似文献   
126.
The results of EFIMOD simulations for black spruce (Picea mariana [Miller]) forests in Central Canada show that climate warming, fire, harvesting and insects significantly influence net primary productivity (NPP), soil respiration (Rs), net ecosystem production (NEP) and pools of tree biomass and soil organic matter (SOM). The effects of six climate change scenarios demonstrated similar increasing trends of NPP and stand productivity. The disturbances led to a strong decrease in NPP, stand productivity, soil organic matter (SOM) and nitrogen (N) pools with an increase in CO2 emission to the atmosphere. However the accumulated NEP for 150 years under harvest and fire fluctuated around zero. It becames negative only at a more frequent disturbance regime with four forest fires during the period of simulation. The results from this study show that changes in climate and disturbance regimes might substantially change the NPP as well as the C and N balance, resulting in major changes in the C pools of the vegetation and soil under black spruce forests.  相似文献   
127.
128.
Mortality associated with gastric ulceration in swine   总被引:1,自引:0,他引:1       下载免费PDF全文
On a large swine operation, necropsy revealed that 39 of 146 (27%) pigs during one week in April and 37 of 137 (27%) pigs during one week in June died from hemorrhage due to gastric ulceration. Contributory factors may have been feed withdrawal one day per week and feeding finely ground pellets.  相似文献   
129.
In female heterogamous (ZW) species, sex-linked genes coding for maternal products that are packaged into the egg open a unique arena for genetic conflict that does not occur in male heterogamous (XY) species. Z-linked maternal-effect alleles that help sons and harm daughters are expected to go to fixation, as are W-linked alleles that help daughters and harm sons. This conflict differs from known cases of meiotic drive, because sex-specific ontogeny, physiology, and gene expression greatly simplify the genetic interactions that lead to sexual conflict. Selection on maternal-effect genes may substantially alter the evolution of ZW compared with XY systems.  相似文献   
130.
This paper presents a comparative study of the roles of Cl? and HCO3 ? in the functioning of the GABAAR-associated Cl?/HCO3 ?-ATPase of the plasma membranes of the olfactory sensory neurons (OSNs) and mature brain neurons (MBNs) of fish. The ATPase activity of OSNs and its dephosphorylation were increased twofold by Cl?(15–30 mmol l?1), whereas the enzyme from MBNs was not significantly affected by Cl?. By contrast, HCO3 ?(15–30 mmol l?1) significantly activated the MBN enzyme and its dephosphorylation, but had no effect on the OSN ATPase. The maximum ATPase activity and protein dephosphorylation was observed in the presence of both Cl?(15 mmol l?1)/HCO3 ?(27 mmol l?1) and these activities were inhibited in the presence of picrotoxin (100 μmol l?1), bumetanide (150 μmol l?1), and DIDS (1000 μmol l?1). SDS-PAGE revealed that ATPases purified from the neuronal membrane have a subunit with molecular mass of ~?56 kDa that binds [3H]muscimol and [3H]flunitrazepam. Direct phosphorylation of the enzymes in the presence of ATP-γ-32P and Mg2+, as well as Cl?/HCO3 ? sensitive dephosphorylation, is also associated with this 56 kDa peptide. Both preparations also showed one subunit with molecular mass 56 kDa that was immunoreactive with GABAAR β3 subunit. The use of a fluorescent dye for Cl? demonstrated that HCO3 ?(27 mmol l?1) causes a twofold increase in Cl? influx into proteoliposomes containing reconstituted ATPases from MBNs, but HCO3 ? had no effect on the reconstituted enzyme from OSNs. These data are the first to demonstrate a differential effect of Cl? and HCO3 ? in the regulation of the Cl?/HCO3 ?-ATPases functioning in neurons with different specializations.  相似文献   
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