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141.
Friederike Ziegler Evelyne A. Groen Sara Hornborg Eddie A. M. Bokkers Kine M. Karlsen Imke J. M. de Boer 《The International Journal of Life Cycle Assessment》2018,23(7):1357-1367
Purpose
Capture fisheries are the only industrial-scale harvesting of a wild resource for food. Temporal variability in environmental performance of fisheries has only recently begun to be explored, but only between years, not within a year. Our aim was to better understand the causes of temporal variability within and between years and to identify improvement options through management at a company level and in fisheries management.Methods
We analyzed the variability in broad environmental impacts of a demersal freeze trawler targeting cod, haddock, saithe, and shrimp, mainly in the Norwegian Sea and in the Barents Sea. The analysis was based on daily data for fishing activities between 2011 and 2014 and the functional unit was a kilo of landing from one fishing trip. We used biological indicators in a novel hierarchic approach, depending on data availability, to quantify biotic impacts. Landings were categorized as target (having defined target reference points) or bycatch species (classified as threatened or as data-limited). Indicators for target and bycatch impacts were quantified for each fishing trip, as was the seafloor area swept.Results and discussion
No significant difference in fuel use was found between years, but variability was considerable within a year, i.e., between fishing trips. Trips targeting shrimp were more fuel intensive than those targeting fish, due to a lower catch rate. Steaming to and from port was less important for fuel efficiency than steaming between fishing locations. A tradeoff was identified between biotic and abiotic impacts. Landings classified as main target species generally followed the maximum sustainable yield (MSY) framework, and proportions of threatened species were low, while proportions of data-limited bycatch were larger. This improved considerably when reference points were defined for saithe in 2014.Conclusions
The variability between fishing trips shows that there is room for improvement through management. Fuel use per landing was strongly influenced by target species, fishing pattern, and fisheries management. Increased awareness about the importance of onboard decision-making can lead to improved performance. This approach could serve to document performance over time helping fishing companies to better understand the effect of their daily and more long-term decision-making on the environmental performance of their products.Recommendations
Fishing companies should document their resource use and production on a detailed level. Fuel use should be monitored as part of the management system. Managing authorities should ensure that sufficient data is available to evaluate the sustainability of exploitation levels of all harvested species.142.
Gammaherpesvirus infection is associated with an increased incidence of lymphoproliferative disease in immunocompromised hosts. Murine gammaherpesvirus 68 (γHV68) infection of BALB β2-microglobulin-deficient (BALB β2m−/−) mice provides an animal model for analysis of the mechanisms responsible for the induction of a lymphoproliferative disease, atypical lymphoid hyperplasia (ALH), that is pathologically similar to posttransplant lymphoproliferative disease associated with Epstein-Barr virus infection. Here we report that the γHV68 v-cyclin and v-bcl-2 genes are required for the efficient induction of γHV68-associated ALH in BALB β2m−/− mice, while the v-GPCR gene is dispensable for ALH induction. In contrast to these findings, deletion of the viral M1 gene enhanced ALH. Thus, γHV68 genes can either inhibit or enhance the induction of lymphoproliferative disease in immunocompromised mice. 相似文献
143.
144.
Friederike Mengel 《PloS one》2014,9(4)
We relate different self-reported measures of computer use to individuals'' propensity to cooperate in the Prisoner''s dilemma. The average cooperation rate is positively related to the self-reported amount participants spend playing computer games. None of the other computer time use variables (including time spent on social media, browsing internet, working etc.) are significantly related to cooperation rates. 相似文献
145.
Pegah Varamini Wei Huang Goh Friederike M. Mansfeld Joanne T. Blanchfield Bruce D. Wyse Maree T. Smith Istvan Toth 《Bioorganic & medicinal chemistry》2013,21(7):1898-1904
We previously described two novel analogues of endomorphin-1 (Tyr-Pro-Trp-Phe-NH2, 1), modified with an 8-carbon lipoamino acid (C8LAA) with or without replacement of Tyr1 with 2,6-dimethyltyrosine (Dmt) at the N-terminus of the peptide (compounds 3 and 4, respectively). They were shown to be more stable and permeable, and acted as potent μ-opioid receptor agonists. In this study we report that the C8LAA modification resulted in successful systemic delivery of both analogues. They produced potent dose-dependent pain relief in a chronic constriction injury-rat model of neuropathic pain after intravenous administration with ED50 values obtained at 6.58 (±1.22) μmol/kg for 3 and 6.18 (±1.17) μmol/kg for 4. Using two different rat models of constipation that assess the effects of μ-opioid receptor agonists on stool hydration and gastro-intestinal motility, compound 3 produced insignificant constipation at 16 μmol/kg, whereas morphine elicited significant constipation at 2 μmol/kg. Compound 3 in contrast to morphine, did not attenuate the hypercapnic ventilatory response at 5 μmol/kg, a dose that fully alleviated hindpaw sensitivity at the time of peak effect in CCI-rats. This finding revealed the lack of respiratory depression effect at antinociceptive dose. 相似文献
146.
147.
Ferwerda G Meyer-Wentrup F Kullberg BJ Netea MG Adema GJ 《Cellular microbiology》2008,10(10):2058-2066
The beta-glucan receptor dectin-1 and Toll-like receptors TLR2 and TLR4 are the main receptors for recognition of Candida albicans by the innate immune system. It has been reported that dectin-1 amplifies TLR2-dependent induction of cytokines in mouse models. In the present study we hypothesized that dectin-1 has potent synergistic effects with both TLR2 and TLR4 in human PBMCs and macrophages. Human PBMCs and monocyte-derived macrophages were stimulated with curdlan, a linear beta-1,3-glucan-polymer derived from Alcaligenes faecalis with specific ligand affinity for dectin-1, in combination with the synthetic TLR2 ligand Pam3Cys and the ultrapure TLR4 ligand LPS. TNF-alpha and IL-10 production was measured in the supernatants with ELISA. Curdlan is a specific dectin-1 ligand without TLR2- or TLR4-stimulating properties. Human primary monocytes and macrophages express dectin-1 on the cell membrane. Stimulation of human PBMCs with curdlan in combination with Pam3Cys or LPS leads to synergistic increase in TNF-alpha production that was inhibited by GE2, a neutralizing dectin-1 antibody. Dectin-1-dependent synergy between curdlan and TLR agonists was also apparent in human monocyte-derived macrophages. Conclusively, dectin-1 synergizes with both TLR2 and TLR4 pathways for the production of TNF-alpha in human primary PBMCs and in monocyte-derived macrophages. 相似文献
148.
Julian Fennessy Friederike Bock Andy Tutchings Rick Brenneman Axel Janke 《African Journal of Ecology》2013,51(4):635-640
Thornicroft's giraffe, Giraffa camelopardalis thornicrofti, is a geographically isolated subspecies of giraffe found only in north‐east Zambia. The population only occurs in Zambia's South Luangwa Valley, an area which interestingly places it between the current distribution of Masai (G. c. tippelskirchi) giraffe to the north, and the Angolan (G. c. angolensis) and South African (G. c. giraffa) giraffe in the south‐west and south, respectively. Specific studies have been undertaken on the ecology of this subspecies, but their population genetics remains unknown. We studied 34 individuals from the South Luangwa National Park and adjacent Lupande Game Management Area and seven individuals from northern Botswana. The complete cytochrome b and control region sequences of the mitochondrial genome were sequenced and analysed together with database data by maximum likelihood tree reconstruction and maximum parsimony network analyses. The giraffe from Zambia's South Luangwa Valley are most closely related to the subspecies G. c. tippelskirchi and part of their radiation. However, they form a unique population that would benefit from increased research and conservation management. 相似文献
149.
Quantitative and dynamic analysis of metabolites and signalling molecules is limited by technical challenges in obtaining temporally resolved information at the cellular and compartmental level. Real-time information on signalling and metabolite levels with subcellular granularity can be obtained with the help of genetically encoded FRET (F?rster resonance energy transfer) nanosensors. FRET nanosensors represent powerful tools for gene discovery, and analysis of regulatory networks, for example by screening mutants. However, RNA silencing has impaired our ability to express FRET nanosensors functionally in Arabidopsis plants. This drawback was overcome here by expressing the nanosensors in RNA silencing mutants. However, the use of silencing mutants requires the generation of homozygous lines deficient in RNA silencing as well as the mutation of interest and co-expression of the nanosensor. Here it is shown that dynamic changes in cytosolic glucose levels can readily be quantified in wild-type Arabidopsis plants at early stages of development (7-15 d) before silencing had a major effect on fluorescence intensity. A detailed protocol for screening 10-20 mutant seedlings per day is provided. The detailed imaging protocol provided here is suitable for analysing sugar flux in young wild-type plants as well as mutants affected in sugar signalling, metabolism, or transport using a wide spectrum of FRET nanosensors. 相似文献
150.
The ability to coordinate with others' head and eye orientation to look in the same direction is considered a key step towards an understanding of others mental states like attention and intention. Here, we investigated the ontogeny and habituation patterns of gaze following into distant space and behind barriers in nine hand-raised wolves. We found that these wolves could use conspecific as well as human gaze cues even in the barrier task, which is thought to be more cognitively advanced than gazing into distant space. Moreover, while gaze following into distant space was already present at the age of 14 weeks and subjects did not habituate to repeated cues, gazing around a barrier developed considerably later and animals quickly habituated, supporting the hypothesis that different cognitive mechanisms may underlie the two gaze following modalities. More importantly, this study demonstrated that following another individuals' gaze around a barrier is not restricted to primates and corvids but is also present in canines, with remarkable between-group similarities in the ontogeny of this behaviour. This sheds new light on the evolutionary origins of and selective pressures on gaze following abilities as well as on the sensitivity of domestic dogs towards human communicative cues. 相似文献