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Nannochloropsis salina was grown on a mixture of standard growth media and pre-gasified industrial process water representing effluent from a local biogas plant. The study aimed to investigate the effects of enriched growth media and cultivation time on nutritional composition of Nannochloropsis salina biomass, with a focus on eicosapentaenoic acid (EPA). Variations in fatty acid composition, lipids, protein, amino acids, tocopherols and pigments were studied and results compared to algae cultivated on F/2 media as reference. Mixed growth media and process water enhanced the nutritional quality of Nannochloropsis salina in laboratory scale when compared to algae cultivated in standard F/2 medium. Data from laboratory scale translated to the large scale using a 4000 L flat panel photo-bioreactor system. The algae growth rate in winter conditions in Denmark was slow, but results revealed that large-scale cultivation of Nannochloropsis salina at these conditions could improve the nutritional properties such as EPA, tocopherol, protein and carotenoids compared to laboratory-scale cultivated microalgae. EPA reached 44.2% ± 2.30% of total fatty acids, and α-tocopherol reached 431 ± 28 µg/g of biomass dry weight after 21 days of cultivation. Variations in chemical compositions of Nannochloropsis salina were studied during the course of cultivation. Nannochloropsis salina can be presented as a good candidate for winter time cultivation in Denmark. The resulting biomass is a rich source of EPA and also a good source of protein (amino acids), tocopherols and carotenoids for potential use in aquaculture feed industry. 相似文献
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Charlotte Descamps Laura Moquet Marc Migon Anne-Laure Jacquemart 《Journal of insect science (Online)》2015,15(1)
As part of an ongoing research project on the pollination networks in European heathlands, the objective of this study was to assess the insect visitor guild on Calluna vulgaris (L.) Hull (Ericaceae). We focused the study on a region renowned for its largely well-preserved heathlands, the Cévennes National Park, Southern France. In 2013, flower visitors were observed over 3 d per site, in four heathland sites at mont Lozère. Honeybees (Apis mellifera L.) were the main visitors (62–88% of total visitors). Besides honeybees, a high diversity of visitors was detected with 57 different species identified (42 Diptera and 15 Hymenoptera). Hoverflies (Syrphidae, Diptera) visitors were abundant and diverse, especially individuals belonging to the genera Eristalis and Episyrphus. The reported diversity of visitors was probably due to the preservation of large heathland areas at mont Lozère and to the generalist pollination system of C. vulgaris.RESUME. Cette étude fait partie d’un projet de recherche en cours sur les réseaux de pollinisation dans les landes européennes. Son objectif est d’évaluer la guilde des insectes visiteurs de Calluna vulgaris (L.) Hull (Ericaceae). Cette étude se déroule dans une région réputée pour ses landes globalement bien préservées: le Parc natinal des Cévennes, situé dans le sud de la France. En 2013, les insectes visiteurs ont été observés durant trois jours par site, dans quatre sites au mont Lozère. Les abeilles domestiques (A. mellifera L.) sont les visiteurs principaux (62–88% du nombre total de visiteurs). Outre les abeilles domestiques, une diversité importante de visiteurs est constatée: 57 espèces ont été identifiées (42 appartenant à l''ordre des Diptères et 15 à l''ordre des Hyménoptères). Les syrphes (Syrphidae, Diptera) sont abondants et diversifiés, en particulier les genres Eristalis et Episyrphus. La diversité de visiteurs observée peut certainement s’expliquer par la préservation de grandes étendues de landes au mont Lozère et par le caractère généraliste de la pollinisation de la callune. 相似文献
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Gon?alo S. Marinho Susan L. Holdt Charlotte Jacobsen Irini Angelidaki 《Marine drugs》2015,13(7):4357-4374
This study is evaluating the seasonal lipid and fatty acid composition of the brown seaweed Saccharina latissima. Biomass was sampled throughout the year (bi-monthly) at the commercial cultivation site near a fish farm in an integrated multi-trophic aquaculture (IMTA) and at a reference site in Denmark (2013–2014). Generally, there was no difference in the biomass composition between sites; however, significant seasonal changes were found. The lipid concentration varied from 0.62%–0.88% dry weight (DW) in July to 3.33%–3.35% DW in November (p < 0.05) in both sites. The fatty acid composition in January was significantly different from all the other sampling months. The dissimilarities were mainly explained by changes in the relative abundance of 20:5n-3 (13.12%–33.35%), 14:0 (11.07%–29.37%) and 18:1n-9 (10.15%–16.94%). Polyunsaturated fatty acids (PUFA’s) made up more than half of the fatty acids with a maximum in July (52.3%–54.0% fatty acid methyl esters; FAME). This including the most appreciated health beneficial PUFA’s, eicosapentaenoic (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3), but also arachidonic (ARA) and stearidonic acid (SDA), which are not found in land vegetables such as cabbage and lettuce. Compared to fat (salmon) and lean fish (cod) this seaweed species contains higher proportions of ARA and SDA, but lower EPA (only cod) and DHA. Conclusively, the season of harvest is important for the choice of lipid quantity and quality, but the marine vegetables provide better sources of EPA, DHA and long-chain (LC)-PUFA’s in general compared to traditional vegetables. 相似文献
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Charlotte Sonne Kristensen Poul Bkbo Vivi Bille-Hansen Anette Btner Hkan Vigre Claes Ene Lars Erik Larsen 《Veterinary microbiology》2009,138(3-4):244-250
In this paper we present the results from two experimental studies (I and II) investigating whether post-weaning multisystemic wasting syndrome (PMWS) can be induced in pigs from PMWS unaffected herds by mingling with pigs from PMWS-affected herds and to observe whether transportation and/or mingling of healthy pigs from unaffected herds could induce PMWS.The studies comprised pigs from 12 different herds. Eight herds had PMWS while four were unaffected. All 12 herds were found to be infected with PCV2. Pigs from PMWS-affected herds were mingled with pigs from unaffected herds in four separate compartments in both study I and study II. In addition, in study II, four groups of pigs from unaffected herds were included. Two groups with pigs transported and mingled from unaffected herds and two groups with pigs which were only transported. The PMWS diagnoses on the individual pigs were based on lymphoid depletion, histiocytic proliferation and the presence of giant cells or inclusion bodies together with the demonstration of PCV2 in lymphoid tissue.Healthy pigs, in both studies, developed PMWS 4–5 weeks after mingling with pigs clinically affected with PMWS. None of the pigs from unaffected herds which had no contact with pigs from PMWS-affected herds developed clinical signs of PMWS. Transportation and mingling of pigs from PMWS unaffected herds in combination or alone was insufficient to provoke PMWS. 相似文献
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Charlotte Sandersen Kathleen McEntee Stefan Deleuze Johanne Detilleux Hélène Amory 《Journal of Equine Veterinary Science》2009
Although echocardiography has greatly improved the diagnostic possibilities in equine medicine, determining the prognosis remains a difficult task. In humans, maximal cardiac power output (CPO) has been described as a powerful indicator of exercise capability and outcome in heart disease. The aim of the study is to describe the measurement of CPO by echocardiography and by thermodilution in healthy horses. Six healthy horses were studied. Cardiac output (CO) was measured by thermodilution and Doppler echocardiography at rest and during a pharmacologic stress test consisting of 35 μg/kg atropine followed by incremental steps 2, 4, 6, and 8 μg/kg/min of dobutamine infusion. Mean arterial pressure (MAP) was measured invasively by a catheter introduced into the transverse facial artery. CPO was calculated as the product of CO and MAP. Baseline CPO measured by thermodilution and by Doppler echocardiography was 10.7 ± 3.3 and 13.7 ± 4.5 watts, respectively. CPO increased significantly with pharmacologic stimulation and reached maximal CPO of 66.4 ± 3.6 and 60.4 ± 5.1 watts when measured by thermodilution and Doppler echocardiography, respectively. This study describes an estimation of CPO in horses. Further studies should demonstrate the usefulness of CPO as a predictive indicator in horses suffering from cardiac disease. 相似文献
70.
A methodology and apparatus have been proposed to indirectly evaluate twist liveliness of spun yarns by measuring the number
of snarl turns formed of a yarn submerged in a water bath. A comparative study was carried out to evaluate the effectiveness
of water in the measurement of yarn snarls. T tests showed that water has a significant effect in the snarl forming and testing
results. Systematic studies were then carried out in the intra and inter laboratories to evaluate the feasibility and accuracy
of the proposed measurement system. The analysis of variance (ANOVA) for the studies showed that there is no significant difference
in measuring twist liveliness between the operators in the same laboratory and between the operators from different laboratories,
respectively. The largest variance in the tests is attributed to the expected variation in the level of snarl turns in different
yarn specimens. The experimental results showed that the developed yarn snarling apparatus has made accurate and repeatable
measurements of twist liveliness over a range of 100 % cotton ring spun yarn counts. 相似文献