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141.
Ole Jørgen Hanssen Elling-Olav Rukke Bernt Saugen Jens Kolstad Pål Hafrom Lars von Krogh Hanne Lerche Raadal Anne Rønning Kristin Støren Wigum 《The International Journal of Life Cycle Assessment》2007,12(4):257-265
Scope and Background
The environmental effectiveness of the Norwegian beverage sector has been studied in a Factor 10 perspective. The objective of the study was to identify strategies that could make the beverage sector radically more effective from an environmental and resource perspective, leading to a Factor 10 improvement. Another main purpose of the work was to test the potential for using Life Cycle Assessment (LCA) methodology on an economic sector with a network of product chains, rather than for a single product.Methods
Life Cycle Assessment data from STØ’s own studies and literature studies have been used as a basis for analysis of the environmental status of the beverage sector in Norway. The functional unit was defined as the amount of beverage products consumed per capita in Norway in the year 2000. The study includes raw material production, production of the beverage product, packaging manufacture, distribution, use and waste management of the products. The study has, for practical reasons, been limited to the environmental impact indicators total energy consumption and global warming potential. This was done as other types of data have been difficult to obtain for all of the products that were studied (tap water, coffee, milk, soft drinks, beer, squash, juice and bottled water).Results and Discussion
The study shows differences between the drinking products with respect to energy consumption and emissions that can contribute to global warming. Due to large uncertainties in the data, general conclusions regarding the differentiation of products based on environmental performance should be made with care. Production and distribution of tap water is, however, significantly less energy intensive than the other products. For the impact categories studied, production of raw materials was the most important part of the life cycle for most drinking products.Conclusions and Perspective
The most significant contributions to achieving a Factor 10 development can be made by consuming more water, especially tap water, and through improving raw material production in the agricultural sector. Packaging and distribution is responsible for only a small part of the energy consumption and emissions leading to global warming. Optimal packaging sizes might however reduce loss of products in the user phase, which is important in order to improve the system. A Factor 10 level seems achievable only if the consumption of tap water is increased to a high level.142.
Fredrik Oftung Martinus Løvik Svein Rune Andersen L.Oddvar Frøholm Gunnar Bjune 《FEMS immunology and medical microbiology》1999,26(1):75-82
We have previously developed a mouse model based on transient bacteraemia in normal B10.M mice to evaluate the protective efficacy of outer membrane vesicle vaccines against serogroup B meningococci. To obtain a course of infection similar to that observed in man, we have in this work modified the mouse model by administration of human holo-transferrin upon bacterial challenge. Co-challenge with holo-transferrin induced increasing bacteraemia and subsequent death in normal non-immune mice, but not in vaccinated animals. The model system is dependent on challenge with meningococci expressing the transferrin receptor which is obtained by culturing the bacteria under iron restriction. The modified model system for protection against meningococcal infection presented here makes it possible to measure outer membrane vesicle vaccine induced protection by using bacteraemia as well as survival as parameters. 相似文献
143.
A pressure spray tank was adapted to supply positive pressure for processing water samples for concentrating viruses with microporous filters under field conditions. This low-cost system allows water to be processed in locations where electric current is not readily available or where light-weight portable equipment is required. 相似文献
144.
Garry K. Brown Oddvar Stokke Egil Jellum 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1978,145(2):177-184
The profile of high boiling point organic acids in urine samples from both normal subjects and patients suspected of having some form of metabolic disorder has been determined by combined gas chromatography—mass spectrometry. Fifteen different compounds eluting after hippuric acid have been identified, including two, cinnamoylglycine and acetyltributylcitrate, which have not been recognised previously. Relative retention times and abbreviated mass spectra of the identified compounds are presented. 相似文献
145.
The overall objective of the study was to investigate changes in quantitative parameters of Atlantic halibut (Hippoglossus hippoglossus L.) semen throughout the reproductive season in order to systematize the knowledge about biology of Atlantic halibut spermatozoa. Semen samples were collected from February to May from broodstock males kept under either a natural or 3-month advanced photoperiod regime. Spermatozoa concentration, semen pH and osmolality, as well as spermatozoa motility parameters were investigated. The use of catheterization of sperm was examined. Also, fertilization tests were performed. We found that spermatozoa concentration increases in a linear-like mode towards the end of the spawning season, which correlated with a decrease in a number of spermatozoa motility parameters, including actual percentage of motile spermatozoa (MOT), curvilinear velocity (VCL) and straight-line velocity (VSL) of spermatozoa. A breakpoint in MOT occurred when spermatozoa reached a concentration in the range of 17-20 x 10(9) spermatozoa/mL. The fertilization ability of sperm from males kept under natural photoperiod decreased in April. Survival of embryos at 80 degrees days produced by fertilizing eggs of single female with sperm from natural photoperiod males was 88, 76 and 41% on April 09 and 17, and May 01, respectively, whereas using sperm from 3-month delayed photoperiod males for fertilizing eggs from the same female on April 27 resulted in 80% of surviving embryos, not differing significantly from the data from April 09. Physical decomposition of spermatozoa was observed towards the end of the season and it was related to an increase in the whole semen osmolality. Catheterization of semen did not improve spermatozoa motility parameters, however, it reduced the variation in recorded values, especially in the case of pH, caused by contamination with feces or urine. Post-seasonal decrease in spermatozoa concentration was likely related to intensive ageing processes. Based on the present study and available data by other researchers, a model of changes of quantitative parameters in Atlantic halibut semen throughout the reproductive season is proposed. 相似文献
146.
147.
Development and characterization of an in vitro ovulation model using mouse ovarian follicles. 总被引:2,自引:0,他引:2
To investigate ovulation, an in vitro model with cultured mouse follicles was developed and compared with an in vivo ovulation model. In this model, secondary follicles were grown in vitro with immature mouse serum (5%) and recombinant human FSH. Addition of ascorbic acid and selenium to the medium increased follicular survival (from 29% to 86%) and resulted in the development of healthy preovulatory follicles (> 400 microm) producing estradiol. Depending on the starting size of the follicles, the preovulatory stage was reached after 4-6 days. The ovulatory response to hCG was maximal in follicles exceeding a diameter of 400 microm. The in vitro-ovulated oocytes could be fertilized and were able to develop to the blastocyst stage. Ovulation induced by hCG was dose dependent, reaching a maximum of 80% at 1 IU/ml. Concomitantly, progesterone production increased from 3.6 +/- 0.5 to 29 +/- 2 ng/ml. Both in vivo and in vitro, hCG induced expression of the progesterone receptor and the prostaglandin endoperoxide synthase-2 (PGS-2) gene within 3 h. Ovulation could be completely blocked with the anti-progestogen Org-31710 and partially (50%) with the PGS inhibitor indomethacin in vitro and in vivo. Org-31710 and indomethacin did not affect progesterone production. In summary, a physiologically relevant in vitro ovulation model of cultured mouse follicles that can be used to study the process of follicular rupture has been developed. 相似文献
148.
Sveinn Are Hanssen Jan Ove Bustnes Lisbeth Schnug Sophie Bourgeon Trond Vidar Johnsen Manuel Ballesteros Christian Sonne Dorte Herzke Igor Eulaers Veerle L. B. Jaspers Adrian Covaci Marcel Eens Duncan J. Halley Truls Moum Rolf Anker Ims Kjell Einar Erikstad 《Ecology and evolution》2013,3(16):5157-5166
Parasites are natural stressors that may have multiple negative effects on their host as they usurp energy and nutrients and may lead to costly immune responses that may cause oxidative stress. At early stages, animals may be more sensitive to infectious organisms because of their rapid growth and partly immature immune system. The objective of this study was to explore effects of parasites by treating chicks of two raptor species (northern goshawk Accipiter gentilis and white‐tailed sea eagle Haliaeetus albicilla) against both endoparasites (internal parasites) and ectoparasites (external parasites). Nests were either treated against ectoparasites by spraying with pyrethrin or left unsprayed as control nests. Within each nest, chicks were randomly orally treated with either an antihelminthic medication (fenbendazole) or sterile water as control treatment. We investigated treatment effects on plasma (1) total antioxidant capacity TAC (an index of nonenzymatic circulating antioxidant defenses), (2) total oxidant status TOS (a measure of plasmatic oxidants), and (3) immunoglobulin levels (a measure of humoral immune function). Treatment against ectoparasites led to a reduction in circulating immunoglobulin plasma levels in male chicks. TOS was higher when not receiving any parasite reduction treatment and when receiving both endo‐ and ectoparasitic reduction treatment compared with receiving only one treatment. TAC was higher in all treatment groups, when compared to controls. Despite the relatively low sample size, this experimental study suggests complex but similar relationships between treatment groups and oxidative status and immunoglobulin levels in two raptor species. 相似文献
149.
Jannike M. Andersen Oddvar Myhre Halvor Aarnes Tor Arne Vestad Frode Fonnum 《Free radical research》2013,47(3):269-279
A fragment of the amyloid beta protein, g A(25-35), was investigated for its effect on production of reactive oxygen species (ROS) in human neutrophil granulocytes. The formation and identification of ROS were examined by using a 2',7'-dichlorofluorescin (DCF) fluorescence assay, a luminol chemiluminescence assay, electron paramagnetic resonance (EPR) spectroscopy with DEPMPO as a spin trap, and hydroxylation of 4-hydroxybenzoate (4-HBA). The DCF assay showed that g A(25-35) stimulated formation of ROS in a concentration and time dependent manner. The inverted peptide, g A(35-25), gave no response. Also, luminol-amplified chemiluminescence was stimulated by g A(25-35). Incubation with diethyldithiocarbamate (a superoxide dimustase inhibitor) and salicylhydroxamate (SHA; a myeloperoxidase inhibitor) reduced the chemiluminescence. This indicates that hypochlorous acid (HOCl) is formed after exposure to g A(25-35). The EPR spectra indicated a concentration dependent formation of superoxide ( O 2 ” m ) - and hydroxyl ( ” OH)- radicals. Hydroxylation of 4-HBA to 3,4,-dihydroxybenzoate confirmed production of ” OH. This response was attenuated by SHA, indicating involvement of HOCl in formation of ” OH. The DCF fluorescence was inhibited with U0126 (an extracellular signal regulated protein kinase (ERK) inhibitor). Further analysis with western blot confirmed phosphorylation of ERK1/2 after exposure to g A(25-35). The phospholipase A 2 (PLA 2 ) inhibitor 7,7-dimethyl-(5Z,8Z)-eicosadienoic acid, and diphenyleneiodonium, which inhibits the NADPH oxidase, also led to a reduction of the DCF fluorescence. The present findings indicate that g A(25-35) stimulates the NADPH oxidase by activating the ERK pathway and PLA 2 . Production of O 2 ” m can lead to HOCl and further formation of ” OH, which both have a cytotoxic potential. 相似文献
150.
Gap formation and dynamics after long‐term steady state in an old‐growth Picea abies stand in Norway: Above‐ and belowground interactions
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Stand dynamics and the gap initiation prior to gap formation are not well‐understood because of its long‐term nature and the scarcity of late‐successional stands. Reconstruction of such disturbance is normally based on historical records and dendroecological methods. We investigated gap initiation and formation at the fine‐scale stand level in the old‐growth reserve of Karlshaugen in Norway. Given its long‐term conservation history, and thorough mapping in permanent marked plots with spatially referenced trees, it provides an opportunity to present stand development before, during, and after gap formation. Late‐successional decline in biomass was recorded after more than 50 years of close to steady state. Gaps in the canopy were mainly created by large old trees that had been killed by spruce bark beetles. Snapping by wind was the main reason for treefall. Long‐term dominance of Norway spruce excluded downy birch and Scots pine from the stand. Comparisons of the forest floor soil properties between the gap and nongap area showed significantly higher concentrations of plant available Ca within the gap area. Plant root simulator (PRS?) probes showed significantly higher supply rates for Ca and Mg, but significantly lower K for the gap compared to the nongap area. Soil water from the gap area had significantly higher C:N ratios compared to the nongap area. Fine‐scale variation with increasing distance to logs indicated that CWD is important for leaking of DOC and Ca. Our long‐term study from Karlshaugen documents gap dynamics after more than 50 years of steady state and a multiscale disturbance regime in an old‐growth forest. The observed disturbance dynamic caused higher aboveground and belowground heterogeneity in plots, coarse woody debris, and nutrients. Our study of the nutrient levels of the forest floor suggest that natural gaps of old‐growth forest provide a long‐lasting biogeochemical feedback system particularly with respect to Ca and probably also N. Norway spruce trees near the gap edge responded with high plasticity to reduced competition, showing the importance of the edge zone as hot spots for establishing heterogeneity, but also the potential for carbon sequestration in old‐growth forest. 相似文献