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171.
Ignacio?HernándezEmail author M.?Angeles?Fernández-Engo J.?Lucas?Pérez-Lloréns Juan?J.?Vergara 《Journal of applied phycology》2005,17(6):557-567
An integrated outdoor cultivation of two macroalgal species: Ulva rotundata (Chlorophyta) and Gracilariopsis longissima (Rhodophyta) was designed. The macroalgae were cultured in effluents from an intensive marine culture (growout phase) of
gilthead seabream Sparus aurata. The biomass evolution of the algal tanks followed a logistic curve, where the approach to the maximum stocking density of
seaweeds was governed by thalli self-shading, as nutrient limitation in the cultivation tank was unlikely. The maximum stocking
density of the system was approximately 27.8 g U. rotundata L−1 (16.7 Kg m−2) and 11.9 g G. longissima L−1 (7.12 Kg m−2). Yield was more than 3 times higher in U. rotundata than in G. longissima. Overall, U. rotundata removed a greater percentage of phosphate (8.9%) and total dissolved inorganic nitrogen (54%) flowing into the algal tanks
than G. longissima. The latter species biofiltered approximately 3.2% of phosphate and 17% of the total dissolved inorganic nitrogen input.
However, mean nutrient uptake rates on wet weight basis were usually higher in G. longissima than in U. rotundata. The production of total oxidised nitrogen in the algal tanks, considered as being the nitrification rate occurring on the
algal fronds by nitrifying bacteria, was less than half of the ammonium uptake by the macroalgae, suggesting that seaweeds
competed efficiently for ammonia against the nitrifyers. The biofiltration during a diel cycle showed that mean phosphate
biofiltration was lower than 4.5% in the two species whereas ammonium was biofiltered efficiently (up to 67%), especially
in U. rotundata. The metal and heavy metal content in the algal tissue at the end of the monitoring period suggested no metal contamination
of tissues so that both macroalgal species could be used in the food industry. The study reveals the value of ecological engineering
techniques in reducing the dissolved nutrient content in effluents from the fish farm, with the prospect of a better management
practises, based on integrated mariculture designs, being developed by the local farmers. 相似文献
172.
Lessons from crystals grown in the Advanced Protein Crystallisation Facility for conventional crystallisation applied to structural biology 总被引:1,自引:0,他引:1
The crystallographic quality of protein crystals that were grown in microgravity has been compared to that of crystals that were grown in parallel on earth gravity under otherwise identical conditions. A goal of this comparison was to assess if a more accurate 3D-structure can be derived from crystallographic analysis of the former crystals. Therefore, the properties of crystals prepared with the Advanced Protein Crystallisation Facility (APCF) on earth and in orbit during the last decade were evaluated. A statistical analysis reveals that about half of the crystals produced under microgravity had a superior X-ray diffraction limit with respect of terrestrial controls. Eleven protein structures could be determined at previously unachieved resolutions using crystals obtained in the APCF. Microgravity induced features of the most relevant structures are reported. A second goal of this study was to identify the cause of the crystal quality enhancement useful for structure determination. No correlations between the effect of microgravity and other system-dependent parameters, such as isoelectric point or crystal solvent content, were found except the reduced convection during the crystallisation process. Thus, crystal growth under diffusive regime appears to be the key parameter explaining the beneficial effect of microgravity on crystal quality. The mimicry of these effects on earth in gels or in capillary tubes is discussed and the practical consequences for structural biology highlighted. 相似文献
173.
Intersexual segregation in foraging microhabitat use by Magellanic Woodpeckers (Campephilus magellanicus): Seasonal and habitat effects at the world's southernmost forests
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Quiterie Duron Jaime E. Jiménez Pablo M. Vergara Gerardo E. Soto Marlene Lizama Ricardo Rozzi 《Austral ecology》2018,43(1):25-34
Animals facing seasonal food shortage and habitat degradation may adjust their foraging behaviour to reduce intraspecific competition. In the harsh environment of the world's southernmost forests in the Magellanic sub‐Antarctic ecoregion in Chile, we studied intersexual foraging differences in the largest South American woodpecker species, the Magellanic Woodpecker (Campephilus magellanicus). We assessed whether niche overlap between males and females decrease when food resources are less abundant or accessible, that is, during winter and in secondary forests, compared to summer and in old‐growth forests, respectively. We analysed 421 foraging microhabitat observations from six males and six females during 2011 and 2012. As predicted, the amount of niche overlap between males and females decreased during winter, when provisioning is more difficult. During winter, males and females (i) used trees with different diameter at breast height (DBH); (ii) fed in trunk sections with different diameters; and (iii) fed at different heights on tree trunks or branches. Vertical niche partitioning between sexes was found in both old‐growth and secondary forests. Such a niche partitioning during winter may be a seasonal strategy to avoid competition between sexes when prey resources are less abundant or accessible. Our results suggest that the conservation of this forest specialist, dimorphic and charismatic woodpecker species requires considering differences in habitat use between males and females. 相似文献
174.
175.
Synthases of cellulose, chitin, hyaluronan, and all other polymers containing (1-->4)beta-linked glucosyl, mannosyl and xylosyl units have overcome a substrate orientation problem in catalysis because the (1-->4)beta-linkage requires that each of these sugar units be inverted nearly 180 degrees with respect to its neighbors. We and others have proposed that this problem is solved by two modes of glycosyl transfer within a single catalytic subunit to generate disaccharide units, which, when linked processively, maintain the proper orientation without rotation or re-orientation of the synthetic machinery in 3-dimensional space. A variant of the strict (1-->4)beta-D-linkage structure is the mixed-linkage (1-->3),(1-->4)beta-D-glucan, a growth-specific cell wall polysaccharide found in grasses and cereals. beta-Glucan is composed primarily of cellotriosyl and cellotetraosyl units linked by single (1-->3)beta-D-linkages. In reactions in vitro at high substrate concentration, a polymer composed of almost entirely cellotriosyl and cellopentosyl units is made. These results support a model in which three modes of glycosyl transfer occur within the synthase complex instead of just two. The generation of odd numbered units demands that they are connected by (1-->3)beta-linkages and not (1-->4)beta-. In this short review of beta-glucan synthesis in maize, we show how such a model not only provides simple mechanisms of synthesis for all (1-->4)beta-D-glycans but also explains how the synthesis of callose, or strictly (1-->3)beta-D-glucans, occurs upon loss of the multiple modes of glycosyl transfer to a single one. 相似文献
176.
Proteomic expression profile of injured rat peripheral nerves revealed biological networks and processes associated with nerve regeneration
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Daniele Vergara Alessandro Romano Eleonora Stanca Velia La Pesa Laura Aloisi Stefania De Domenico Julien Franck Ilaria Cicalini Anna Giudetti Elisa Storelli Damiana Pieragostino Isabelle Fournier Alessandro Sannino Michel Salzet Federica Cerri Angelo Quattrini Michele Maffia 《Journal of cellular physiology》2018,233(8):6207-6223
177.
Stuart J. Corr Sabeel Shamsudeen Leoncio A. Vergara Jason Chak-Shing Ho Matthew J. Ware Vazrik Keshishian Kenji Yokoi David J. Savage Ismail M. Meraz Warna Kaluarachchi Brandon T. Cisneros Mustafa Raoof Duy Trac Nguyen Yingchun Zhang Lon J. Wilson Huw Summers Paul Rees Steven A. Curley Rita E. Serda 《PloS one》2015,10(8)
Herein, we present a novel imaging platform to study the biological effects of non-invasive radiofrequency (RF) electric field cancer hyperthermia. This system allows for real-time in vivo intravital microscopy (IVM) imaging of radiofrequency-induced biological alterations such as changes in vessel structure and drug perfusion. Our results indicate that the IVM system is able to handle exposure to high-power electric-fields without inducing significant hardware damage or imaging artifacts. Furthermore, short durations of low-power (< 200 W) radiofrequency exposure increased transport and perfusion of fluorescent tracers into the tumors at temperatures below 41°C. Vessel deformations and blood coagulation were seen for tumor temperatures around 44°C. These results highlight the use of our integrated IVM-RF imaging platform as a powerful new tool to visualize the dynamics and interplay between radiofrequency energy and biological tissues, organs, and tumors. 相似文献
178.
Jose Luis Araus Shawn Carlisle Kefauver Omar Vergara‐Díaz Adrian Gracia‐Romero Fatima Zahra Rezzouk Joel Segarra Maria Luisa Buchaillot Melissa Chang‐Espino Thomas Vatter Rut Sanchez‐Bragado José Armando Fernandez‐Gallego Maria Dolores Serret Jordi Bort 《植物学报(英文版)》2022,64(2):592-618
High-throughput crop phenotyping, particularly under field conditions, is nowadays perceived as a key factor limiting crop genetic advance. Phenotyping not only facilitates conventional breeding, but it is necessary to fully exploit the capabilities of molecular breeding, and it can be exploited to predict breeding targets for the years ahead at the regional level through more advanced simulation models and decision support systems. In terms of phenotyping, it is necessary to determined which selection traits are relevant in each situation, and which phenotyping tools/methods are available to assess such traits. Remote sensing methodologies are currently the most popular approaches, even when lab-based analyses are still relevant in many circumstances. On top of that, data processing and automation, together with machine learning/deep learning are contributing to the wide range of applications for phenotyping. This review addresses spectral and red–green–blue sensing as the most popular remote sensing approaches, alongside stable isotope composition as an example of a lab-based tool, and root phenotyping, which represents one of the frontiers for field phenotyping. Further, we consider the two most promising forms of aerial platforms (unmanned aerial vehicle and satellites) and some of the emerging data-processing techniques. The review includes three Boxes that examine specific case studies. 相似文献
179.
180.
In the agricultural areas near Santiago, Chile,ca. 780 kg N ha?1 yr?1 are added to vegetable cropsvia irrigation with untreated sewage effluent draining from the metropolitan area. Nitrate levels in surface wells in the area, from which drinking water is derived, often exceed established limits for human consumption. Of the 779 kg N ha?1 added to crops in one year, 161–287 kg N ha?1 yr?1 were removed by crop harvest and much of the remainder apparently eventually leached to the 1–15 m deep water table. 相似文献