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61.
F. J. Benitez J. Beltran-Heredia F. J. Real J. L. Acero 《Bioprocess and biosystems engineering》1999,21(5):459-464
The decomposition of the organic substrate present in wine distillery wastewaters (WDW) is studied in batch reactors, by an ozonation process, by an aerobic degradation and by another ozonation of the aerobically pretreated wastewaters. In the ozonation process, the effects on the substrate removal obtained of the temperature, pH and the presence of H2O2 and UV radiation are established, and an approximate kinetic study is conducted which leads to the evaluation of the apparent kinetic constants for the substrate reduction. In the aerobic degradation treatment, the evolution of the substrate, biomass and total phenolic compounds are followed during the process, and a kinetic study is performed by using the Contois model, which applied to the experimental data provides the specific kinetic parameters qmax and K1. Finally, in the ozonation of the pretreated wastewaters, the?influence of the operating variables is established, and the effect of this aerobic pretreatment on the substrate removal and kinetic constants obtained in the ozonation stage is also discussed. 相似文献
62.
Jesús Olivero John E. Fa Miguel A. Farfán Jerome Lewis Barry Hewlett Thomas Breuer Giuseppe M. Carpaneto María Fernández Francesco Germi Shiho Hattori Josephine Head Mitsuo Ichikawa Koichi Kitanaishi Jessica Knights Naoki Matsuura Andrea Migliano Barbara Nese Andrew Noss Dieudonné Ongbwa Ekoumou Pascale Paulin Raimundo Real Mike Riddell Edward G. J. Stevenson Mikako Toda J. Mario Vargas Hirokazu Yasuoka Robert Nasi 《PloS one》2016,11(1)
Pygmy populations occupy a vast territory extending west-to-east along the central African belt from the Congo Basin to Lake Victoria. However, their numbers and actual distribution is not known precisely. Here, we undertake this task by using locational data and population sizes for an unprecedented number of known Pygmy camps and settlements (n = 654) in five of the nine countries where currently distributed. With these data we develop spatial distribution models based on the favourability function, which distinguish areas with favourable environmental conditions from those less suitable for Pygmy presence. Highly favourable areas were significantly explained by presence of tropical forests, and by lower human pressure variables. For documented Pygmy settlements, we use the relationship between observed population sizes and predicted favourability values to estimate the total Pygmy population throughout Central Africa. We estimate that around 920,000 Pygmies (over 60% in DRC) is possible within favourable forest areas in Central Africa. We argue that fragmentation of the existing Pygmy populations, alongside pressure from extractive industries and sometimes conflict with conservation areas, endanger their future. There is an urgent need to inform policies that can mitigate against future external threats to these indigenous peoples’ culture and lifestyles. 相似文献
63.
John E. Fa Jesús Olivero Miguel ángel Farfán Ana Luz Márquez Juan Mario Vargas Raimundo Real Robert Nasi 《PloS one》2014,9(11)
Wild animals are a primary source of protein (bushmeat) for people living in or near tropical forests. Ideally, the effect of bushmeat harvests should be monitored closely by making regular estimates of offtake rate and size of stock available for exploitation. However, in practice, this is possible in very few situations because it requires both of these aspects to be readily measurable, and even in the best case, entails very considerable time and effort. As alternative, in this study, we use high-resolution, environmental favorability models for terrestrial mammals (N = 165) in Central Africa to map areas of high species richness (hot spots) and hunting susceptibility. Favorability models distinguish localities with environmental conditions that favor the species'' existence from those with detrimental characteristics for its presence. We develop an index for assessing Potential Hunting Sustainability (PHS) of each species based on their ecological characteristics (population density, habitat breadth, rarity and vulnerability), weighted according to restrictive and permissive assumptions of how species'' characteristics are combined. Species are classified into five main hunting sustainability classes using fuzzy logic. Using the accumulated favorability values of all species, and their PHS values, we finally identify weak spots, defined as high diversity regions of especial hunting vulnerability for wildlife, as well as strong spots, defined as high diversity areas of high hunting sustainability potential. Our study uses relatively simple models that employ easily obtainable data of a species'' ecological characteristics to assess the impacts of hunting in tropical regions. It provides information for management by charting the geography of where species are more or less likely to be at risk of extinction from hunting. 相似文献
64.
Heme Biosynthetic Pathway is Functionally Linked to Adipogenesis via Mitochondrial Respiratory Activity
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65.
The role of conservative versus innovative nesting behavior on the 25‐year population expansion of an avian predator
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Andreia Dias Luís Palma Filipe Carvalho Dora Neto Joan Real Pedro Beja 《Ecology and evolution》2017,7(12):4241-4253
Species ranges often change in relation to multiple environmental and demographic factors. Innovative behaviors may affect these changes by facilitating the use of novel habitats, although this idea has been little explored. Here, we investigate the importance of behavior during range change, using a 25‐year population expansion of Bonelli's eagle in southern Portugal. This unique population is almost exclusively tree nesting, while all other populations in western Europe are predominantly cliff nesting. During 1991–2014, we surveyed nest sites and estimated the year when each breeding territory was established. We approximated the boundaries of 84 territories using Dirichlet tessellation and mapped topography, land cover, and the density of human infrastructures in buffers (250, 500, and 1,000 m) around nest and random sites. We then compared environmental conditions at matching nest and random sites within territories using conditional logistic regression, and used quantile regression to estimate trends in nesting habitats in relation to the year of territory establishment. Most nests (>85%, n = 197) were in eucalypts, maritime pines, and cork oaks. Nest sites were farther from the nests of neighboring territories than random points, and they were in areas with higher terrain roughness, lower cover by agricultural and built‐up areas, and lower road and powerline densities. Nesting habitat selection varied little with year of territory establishment, although nesting in eucalypts increased, while cliff nesting and cork oak nesting, and terrain roughness declined. Our results suggest that the observed expansion of Bonelli's eagles was facilitated by the tree nesting behavior, which allowed the colonization of areas without cliffs. However, all but a very few breeding pairs settled in habitats comparable to those of the initial population nucleus, suggesting that after an initial trigger possibly facilitated by tree nesting, the habitat selection remained largely conservative. Overall, our study supports recent calls to incorporate information on behavior for understanding and predicting species range shifts. 相似文献
66.
Kemnitzer W Jiang S Zhang H Kasibhatla S Crogan-Grundy C Blais C Attardo G Denis R Lamothe S Gourdeau H Tseng B Drewe J Cai SX 《Bioorganic & medicinal chemistry letters》2008,18(20):5571-5575
As a continuation of our efforts to discover and develop the apoptosis inducing 4-aryl-4H-chromenes as potential anticancer agents, we explored the removal of the chiral center at the 4-position and prepared a series of 4-aryl-2-oxo-2H-chromenes. It was found that, in general, removal of the chiral center and replacement of the 2-amino group with a 2-oxo group were tolerated and 4-aryl-2-oxo-2H-chromenes exhibited SAR similar to 4-aryl-2-amino-4H-chromenes. The 4-aryl-2-oxo-2H-chromenes with a N-methyl pyrrole fused at the 7,8-positions were highly active with compound 2a having an EC(50) value of 13 nM in T47D cells. It was found that an OMe group was preferred at the 7-position. 7-NMe(2), 7-NH(2), 7-Cl and 7,8 fused pyrido analogs all had low potency. These 4-aryl-2-oxo-2H-chromenes are a series of potent apoptosis inducers with potential advantage over the 4-aryl-2-amino-4H-chromenes series via elimination of the chiral center at the 4-position. 相似文献
67.
Iis Siti Jahro Djulia Onggo Susanto Imam Rahayu M. Carmen Muñoz Ana B. Gaspar Maksym Seredyuk Philipp Gütlich José Antonio Real 《Inorganica chimica acta》2008,361(14-15):4047-4054
Three new compounds formulated (ClO4)2[Fe(pq)3] (1), (BF4)2[Fe(pq)3] · EtOH (2) and {(ClO4)[MnCr(C2O4)3][Fe(pq)2(H2O)2]} (3), where pq is 2,2′-pyridylquinoline, have been synthesised and characterised. Despite the different crystal packing exhibited by 1 and 2, the cationic species [Fe(pq)3]2+ are structurally quite similar. At 293 K, the Fe–N bond lengths are characteristic of the iron(II) in the high-spin state. In contrast to 1, 2 undergoes a continuous spin transition. Indeed, at 95 K its structure experiences a noticeable change in the Fe–N bonds and angles, i.e. the Fe–N bonds shorten by 0.194 Å on the average. The magnetic behaviour confirms that 1 is fully high-spin in the 4–300 K temperature range while 2 shows a spin transition centred at T1/2 = 150 K. The corresponding enthalpy, entropy and interaction parameter are ΔH = 7.49 kJ mol?1, ΔS = 50 J K?1 mol?1and Γ = 1.35 kJ mol?1. Compound 3 has been obtained as a microcrystalline powder. The magnetic properties of 3 point at the occurrence of ferromagnetic coupling below 100 K and the onset of a ferromagnetic ordering below 10 K (Weiss constant equal to 6.8 K). The Mössbauer spectra of 3 show the occurrence of a magnetic order at T ? 4.2 K. 相似文献
68.
Miriam Perez Rebeca Real Julio G. Prieto Ana I. Alvarez 《Chemico-biological interactions》2009,180(1):106-166
The study characterizes the interaction between BCRP/ABCG2 and moxidectin by means of cellular transport, and pharmacokinetic studies in Bcrp1 (−/−) and wild-type mice. Milbemycin moxidectin ([3H]-moxidectin) was tested for its ability to be transported across MCDK-II epithelial monolayer cultures transfected with BCRP. In a second approach, accumulation assays by BCRP-expressing Xenopus laevis oocytes were carried out. Finally, pharmacokinetic studies were performed in order to establish the role of the transporter in milk secretion and tissue distribution. The efflux was negligible in polarized cells but moxidectin was efficiently transported in BCRP-expressing X. laevis oocytes. The transport was blocked by an acridone derivative, a novel BCRP inhibitor. Moxidectin secretion into breast milk was decreased in Bcrp1-knockout mice and the milk to plasma ratio was 2-fold higher in wild-type mice after i.v. administration. Drug accumulation in intestinal content, bile, and intestine was higher in wild-type mice but the plasma concentration was not different.Moxidectin is identified as a BCRP substrate since its Bcrp1-mediated secretion into breast milk and the involvement of Bcrp1 in intestinal and bile secretion has been demonstrated. This interaction has pharmacokinetic and toxicological consequences. The most important toxicological consequences of the interaction between BCRP and moxidectin may be related with the presence of drug residues in milk. 相似文献
69.
70.
Anaïs Baudot Francisco X. Real José M. G. Izarzugaza Alfonso Valencia 《EMBO reports》2009,10(4):359-366
Cancer genome projects are now being expanded in an attempt to provide complete landscapes of the mutations that exist in tumours. Although the importance of cataloguing genome variations is well recognized, there are obvious difficulties in bridging the gaps between high‐throughput resequencing information and the molecular mechanisms of cancer evolution. Here, we describe the current status of the high‐throughput genomic technologies, and the current limitations of the associated computational analysis and experimental validation of cancer genetic variants. We emphasize how the current cancer‐evolution models will be influenced by the high‐throughput approaches, in particular through efforts devoted to monitoring tumour progression, and how, in turn, the integration of data and models will be translated into mechanistic knowledge and clinical applications. 相似文献