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91.
Overall development of a bioprocess for the outdoor production of Nannochloropsis gaditana for aquaculture
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Karina Riveros Claudia Sepulveda Jazmín Bazaes Paola Marticorena Carlos Riquelme Gabriel Acién 《Aquaculture Research》2018,49(1):165-176
In this paper, a systematic methodology is shown for the scaling‐up of Nannochloropsis gaditana production for aquaculture uses. First, an adequate culture medium was developed, prepared using fertilizers instead of pure chemicals. Subsequently, the performance of N. gaditana was modelled as a function of average irradiance; this model being validated in continuous culture experiments. The model was used to determine the optimal dilution rate as well as the expected biomass concentration and productivity at optimal conditions. Finally, outdoor experiments were performed to confirm the model's validity and to determine optimal conditions at real production step. Biomass productivity values of up to 0.08 g L?1 day?1 were obtained at an optimal dilution rate of 0.25 per day in 0.2 m wide flat‐panel reactors using culture medium containing 0.4 g/L NO?3 and 0.034 g/L·PO4?3. Fish trials with Atlantic Salmon demonstrated that the inclusion of produced biomass into fed increase the final weight up to 5%, thus confirming the adequacy of the biomass produced for aquaculture uses. The growth model and the scaling‐up strategy proposed here are necessary to develop real industrial‐scale processes capable of supplying microalgal biomass to the aquaculture markets, which in turn require a guaranteed supply and quality of the raw materials provided. 相似文献
92.
Ghasem Ali Parad Masoud Tabari Kouchaksaraei Gustavo Gabriel Striker Seyed Ehsan Sadati Kazem Nourmohammadi 《Scandinavian Journal of Forest Research》2016,31(5):458-466
Tolerance to flooding is crucial when thinking in promissory species for restoration of ecosystems prone to suffer soil water excess. In this study, we tested the flooding tolerance of two-years-old seedlings of Chestnut-leaved oak (Quercus castaneifolia C.A.Mey.) to determine whether it can be recommended for use in wetland restoration programs. Seedlings of Q. castaneifolia were subjected to three treatments: (1) control (C), (2) flooding for 60 days followed by a 42-day recovery period (F?+?R) and (3) continuous flooding for 102 days (F). Physiological performance, plant morphological changes and biomass accumulation were assessed. Results showed that, although net photosynthetic rates, stomatal conductance and transpiration decreased with prolonged flooding, when flood waters were removed, plants were able to recover their physiological activity (49–80% compared to controls). By contrast, when plants were continually flooded, their physiological activity decreased as well as the leaves experienced precocious senescence and wilting. Biomass responses paralleled physiological responses: leaf and root biomass were 42–49% higher under F?+?R treatment than under continuous flooding, and all plants under the F?+?R survived. Therefore, Q. castaneifolia appears as a promising species to be further studied when thinking re-vegetation of riverine areas and other temporarily flooded wetlands. 相似文献
93.
Raissa Rachel Salustriano da Silva-Matos Gabriel Barbosa da Silva Jr Adenaelson de Souza Marques Maciel Lima Monteiro Josy Anteveli Osajima 《Archives of Agronomy and Soil Science》2016,62(3):445-455
The identification of alternative substrates suitable for seedling production is very important, while boron nutrition is also relevant due to plant requirement and its difficult management. Thus, four experiments were carried out from October 2012 to April 2013 to evaluate the effect of substrates using decomposed buriti (Mauritia vinifera Mart.) stem (DBS) and boron fertilizing for seedling production of yellow passion fruit (Passiflora edulis Sims). The experimental design was completely randomized in factorial scheme 6 × 2 + 1, referring to the substrates [S1: DBS, S2: soil and sand 1:1 (20%) + DBS (80%), S3: soil and sand 1:1 (40%) + DBS (60%), S4: soil and sand 1:1 (60%) + DBS (40%), S5: soil and sand 1:1 (80%) + DBS (20%), S6: commercial substrate (additional treatment) and S7: soil, sand and manure 1:1:2] with and without boron. The seedling emergence, emergence rate, plant height, stem diameter, root length, root volume and dry mass of roots and shoots were recorded. The substrates S2 (without B fertilizing) and S4 (B fertilized with 0.5 mg dm?3) produced seedlings with more than 3.0 g of shoot dry mass and at least 30 cm in height, and can be used for production of high-quality yellow passion fruit seedlings. 相似文献
94.
95.
P. Gabriel A. Pfeil E. Ludewig P. Böttcher G. Oechtering 《The Journal of small animal practice》2009,50(2):92-94
Clinical signs, radiological, arthroscopic findings and magnetic resonance imaging features of a male German shepherd dog with incomplete ossification of the humeral condyle are described. The dog showed recurrent left forelimb lameness and pain on elbow palpation. In routine radiographs, the lesion was obscured. In oblique radiographs, a radiolucent line was detected, and magnetic resonance imaging clearly demonstrated a defect in the humeral condyle. However, arthroscopy showed no changes or discontinuity of the humeral cartilage. Incomplete ossification of the humeral condyle may be underrepresented in conventional, routine studies because if there is concurrent additional elbow pathology (for example fragmented coronoid process), treatment may lead to clinical improvement and further diagnostic techniques may not be performed. The benefit of magnetic resonance imaging in this case is demonstrated. 相似文献
96.
López-Hurtado M Arteaga-Troncoso G Escobedo-Guerra MR Guerra-Infante FM 《Veterinary immunology and immunopathology》2009,127(1-2):181-185
Endocytic activity of phagocytic cells from armadillos infected with viruses, parasites or bacteria is unknown. This report shows that eosinophils from armadillos infected with microfilaria act against these helmintic parasites but have deficiencies in their oxygen-dependent bacteriocidal mechanisms and also in endocytic capacity against yeast. 相似文献
97.
Neil R Smalheiser Vetle I Torvik Amanda Bischoff-Grethe Lauren B Burhans Michael Gabriel Ramin Homayouni Alireza Kashef Maryann E Martone Guy A Perkins Diana L Price Andrew C Talk Ruth West 《Journal of Biomedical Discovery and Collaboration》2006,1(1):8
Arrowsmith is a unique computer-assisted strategy designed to assist investigators in detecting biologically-relevant connections between two disparate sets of articles in Medline. This paper describes how an inter-institutional consortium of neuroscientists used the UIC Arrowsmith web interface http://arrowsmith.psych.uic.edu in their daily work and guided the development, refinement and expansion of the system into a suite of tools intended for use by the wider scientific community. 相似文献
98.
In the contemporary Amazon, ‘discourse’ is increasingly a new means of exercising power, influencing local society and the ways in which natural resources are managed. As society becomes ever more complex, direct means of exercising power no longer enjoy the same legitimacy and efficacy. Discourses are instead now assuming a dominant role in defining governance regimes; the sense of what is correct and socially acceptable, and what is not. This is particularly relevant for the rapidly advancing development frontiers in the Amazon region, where local communities are coming into contact with external players highly interested in their forest resources. This study focuses on understanding how external discourses can restrict the Amazonian communities' options for using their forests, but also how communities can harness these discourses to achieve their own claims and objectives. Empirical evidence from four study areas in the Bolivian, Brazilian and Peruvian Amazon regions is used to show how discourses on sustainable forest management are moulding forestry governance. The conclusion shows that while the discourses used by loggers and development organisations are strongly influencing the way communities manage their forests, some communities are also successfully using these discourses in alliances with environmental organisations to achieve acknowledgment of their demands. 相似文献
99.
N Ferretti G Pompozzi S Copperi F Pérez-Miles A González 《Journal of insect science (Online)》2012,12(31):1-16
Abstract The diversity, abundance, spatial distribution, and phenology of the mygalomorph spider community in the "Ernesto Tornquist" Strict Nature Reserve were analyzed in this study. Located in southwestern Buenos Aires, Argentina, the Reserve is representative of the Ventania system, which is a sigmoidal mountain belt 180 km in length. This exceptional hilly ecosystem is home for many endemic species and rich native fauna and flora. Spider abundance was sampled monthly from October 2009 to October 2010 by hand capture and pitfall traps on grassland slopes. The species recorded in the study area were: Actinopus sp.1 (Actinopodidae); Grammostola vachoni and Plesiopelma longisternale (Theraphosidae); Acanthogonatus centralis (Nemesiidae); and Mecicobothrium thorelli (Mecicobothriidae). Grammostola vachoni and Acanthogonatus centralis were the dominant species in hand capture and pitfall traps, respectively. The seasonal variation, diversity, and abundance of the mygalomorph community are analyzed and discussed here. The Mygalomorphae of the Ventania system comprises an important group of sedentary and cryptozoic spiders that seem to be highly dependent on habitat type and environmental factors. 相似文献
100.
S. R. Sánchez-Peña M. R. Sánchez-Ovalle Gabriel Gallegos-Morales Abiel Sánchez-Arizpe 《Phytoparasitica》2008,36(4):322-325
Fungus-growing ants have been found recently to be symbiotic with actinomycetes living on the ant’s cuticle; these bacteria
are inhibitory to soil fungi that are detrimental to the ants’ fungus gardens. In order to investigate whether actinomycetes
found on the cuticle of attine ants also had inhibitory properties against plant pathogenic fungi, we isolated 32 strains
of actinomycetes from fungus-growing ants (Atta, Trachymyrmex, andCyphomyrmex), from the Mexican states of Coahuila, Nuevo León and Tamaulipas. Of the actinomycetes tested against selected plant pathogenic
fungi (Alternaria solani, Aspergillus flavus, Colletotrichum lindemuthianum, Rhizoctonia solani, Sclerotium sp.) on Czapek-Dox agar medium, 13 isolates inhibited at least one of the fungi.C. lindemuthianum was inhibited by 11 actinomycetes, andRhizoctonia by three. An actinomycete strain isolated fromCyphomyrmex rimosus inhibited all five fungi tested.
http://www.phytoparasitica.org posting July 30, 2008. 相似文献