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231.
Ilie S. Racotta Elena Palacios Ana M. Ibarra José Luis Ramírez Fabiola Arcos Olivia Arjona 《Marine Biology》2008,153(6):1245-1256
Induction of triploidy in aquatic organisms has increased worldwide in the last two decades, mostly because triploids have
better growth than diploids. According to a physiological hypothesis, partial or total sterility of triploids allows the accumulation
of reserves in muscle and other tissues instead of being transferred to the gonad. The present study analyzes lipid, protein,
carbohydrate, and fatty acid levels in muscle and gonads of Nodipecten subnodosus triploids and diploids over 18 months from June 2001 to December 2002. An important increase in gonadosomatic index of diploids
scallops was observed from May to June 2002 reaching the highest values in August. Such increase was not observed in triploid
scallops. Changes in biochemical composition in female gonad were in general related to the accumulation of reserves during
gonad development of diploid scallops. This accumulation was lower for triploid scallops, in accordance to their sterility,
especially for carbohydrates and acylglycerides. Adductor muscle index as well as protein and carbohydrate levels in muscle
increased in both ploidy groups during the reproductive period indicating no mobilization of reserves to sustain gonad development
in both ploidy groups. These results partially support the physiological hypothesis on the advantage of triploids: in a rich
food locality no mobilization of reserves is needed to sustain gametogenesis. This, together with a possible lower efficiency
of energy assimilation at high food concentration for triploids, may be the reason for an apparent lack of superiority of
N. subnodosus triploids in terms of adductor muscle growth. Only the levels of particular highly unsaturated fatty acids levels (namely
20:4n-6 and 20:5n-3) in muscle of diploid and triploid decreased during the reproductive period, indicating a possible transfer of selected
fatty acids to gonads, even in triploids. The muscle of triploids has a slightly but significantly higher proportion of 22:6n-3 compared to diploids, which can have implications for the nutritional and commercial value of triploid adductor muscle. 相似文献
232.
233.
Elizabeth A. Langridge Ana B. Sendova-Franks Nigel R. Franks 《Behavioral ecology and sociobiology》2008,62(12):1851-1861
Colonies of the ant Temnothorax albipennis improve their collective performance over successive emigrations (Langridge et al. Behav Ecol Sociobiol 56:523–529, 2004,
Behav Ecol Sociobiol 62:447–456, 2008). Here, by analysing the performance of individual transporters (workers that carry
the brood, queen and a proportion of adults), we investigate whether they spend less time at the old and new nests during
repeated emigrations. Transporters expedited choosing and picking up brood items at the old nest and depositing them in the
new nest. Such improvements were not associated with adult transport. Generally, when carrying brood items, but not when carrying
adults, transporters visited several locations in the new nest before depositing them. Transporters did not interact with
other adults when depositing brood items. Consequently, reductions in depositing times are the sum of time savings made by
individual transporters. By contrast, transporters spent most time interacting with other adults before picking up brood items
at the old nest. As the frequency of these interactions did not decline, we suggest the behaviours of interacting adults were
modified in a way that hastened their completion. Thus, reductions in picking-up times probably occur because of time saved
during interactions. 相似文献
234.
The Power of Innovation and Strategic Sustainability Positioning: A Survey of the Mining Sector in Brazil
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Luciana Aparecida Barbieri da Rosa Clandia Maffini Gomes Jordana Marques Kneipp Ana Paula Perlin 《环境质量管理》2015,25(2):47-62
This study investigates the relationship between the power of innovation and the sustainability strategies of companies involved in the minerals extraction sector in Brazil. The study included companies associated with the Brazilian Mining Institute, and it used research surveys to gather data. Analysis of the survey data revealed that companies with highly intensive characteristics in regard to innovation and environmental activities (environmental management activities) also display offensive, or proactive, strategies for pursuing sustainability. 相似文献
235.
Pablo Resco Ana Iglesias Isabel Bardají Vicente Sotés 《Regional Environmental Change》2016,16(4):979-993
Our aim was to explore the adaptation choices to climate change in the grapevine regions of Spain from two points of view. First, what are the main reasons for concern? Second, how large is the adaptation effort in each region? We address the first question by measuring sensitivity to climate change with Huglin, Cold Night and Dryness Indices over the entire territory, providing information on the adaptation type (e.g. varieties, zoning, water allocation). We then estimate probabilistic projections across scenario, zone and sensitivity indices in the 56 Protected Designation of Origin areas to inform on the magnitude of the adaptation effort. Second, we propose an adaptation effort measure that is framed according to the local environmental context. Results suggest that most areas urgently need an adaptation plan due to the deterioration of production and quality indices as a result of climate change. Potential opportunities in many climate regions might be limited by current policy. The production objectives of quality and quantity trade-offs will probably need to be revised by analysing the sustainability of grapevine production. 相似文献
236.
Maria Elisabete F. Silva Luís Teixeira de Lemos Olga C. Nunes Ana Cristina Cunha-Queda 《Waste management (New York, N.Y.)》2014,34(1):21-27
The influence of the proportion of C- and N-rich raw materials (initial C/N ratio) and bulking agent on the chemical functional groups composition, humic-like substances (HS-like) content and physicochemical properties of composts was assessed. To achieve these goals, seven initial mixtures (BA1–6 and C1) of dog food (N-rich raw material) were composted with wheat flour (C-rich raw material). Composts were analyzed in terms of chemical functional groups, physicochemical, maturity and stability parameters.The C-rich raw material favored the formation of oxidized organic matter (OM) during the composting process, as suggested by the variation of the ratios of the peaks intensity of FT-IR spectra, corresponding to a decrease of the polysaccharides and an increase of aromatic and carboxyl-containing compounds. However, although with high proportion of C-rich raw material, mixtures with low initial C/N seems to have favored the accumulation of partially oxidized OM, which may have contributed to high electrical conductivity values in the final composts. Therefore, although favoring the partial transformation of OM into stabilized HS-like, initial mixtures with high proportion of C-rich raw material but with low initial C/N led to unstable composts.On the other hand, as long as a high percentage of bulking agent was used to promote the structure of biomass and consequently improve of the aeration conditions, low initial C/N was not a limiting factor of OM oxidation into extractable stabilized humic-like acids. 相似文献
237.
Bigliardi Ana Paula Fernandes Caroline Lopes Feijo Pinto Edlaine Acosta dos Santos Marina Garcia Edariane Menestrino Baisch Paulo Roberto Martins Soares Maria Cristina Flores Muccillo-Baisch Ana Luíza da Silva Júnior Flavio Manoel Rodrigues 《Environmental science and pollution research international》2021,28(2):1409-1416
Environmental Science and Pollution Research - Coal extraction and processing generate environmental contamination, which has several negative impacts on human health. Hematological and biochemical... 相似文献
238.
Oliveira Maria Roniele Félix do Vale Abreu Katiany Romão Ana Lúcia Eufrázio Davi Dalila Maria Barbosa de Carvalho Magalhães Carlos Emanuel Carrilho Elma Neide Vasconcelos Martins Alves Carlucio Roberto 《Environmental science and pollution research international》2021,28(15):18941-18952
Environmental Science and Pollution Research - Plant-based biomass (CFB (carnauba fruit biomass)) obtained from the fruit exocarp of the species Copernicia prunifera (Mill.) H.E. Moore (carnauba)... 相似文献
239.
Osajima Josy A. Sá Alexandro S. Honorio Luzia M. C. Trigueiro Pollyana Pinto Lucas I. F. Oliveira Joziel A. Furtini Marcelo B. Bezerra Roosevelt D. S. Alcantara Ana C. S. Silva-Filho Edson C. 《Environmental science and pollution research international》2021,28(19):23995-24007
Environmental Science and Pollution Research - Herbicides are hazardous organic pollutants that contribute to the risk of environmental contamination. The aim of this work was to investigate the... 相似文献
240.
Testolin Renan C. Feuzer-Matos Ana Júlia Cotelle Sylvie Adani Fabrizio Janke Leandro Poyer-Radetski Gabriel Pereira Antonio C. Ariente-Neto Rafael Somensi Cleder A. Radetski Claudemir M. 《Environmental science and pollution research international》2021,28(36):49642-49650
Environmental Science and Pollution Research - Recalcitrant dyes found in textile wastewater represent a threat for sustainable textile production due to their resistance to conventional... 相似文献