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251.
Giancarlo Cravotto Stefano Di Carlo Arianna Binello Stefano Mantegna Mariangela Girlanda Alexandra Lazzari 《Water, air, and soil pollution》2008,187(1-4):353-359
Advanced oxidation processes (AOPs) are among the most efficient methods for wastewater treatment. To achieve the degradation of persistent organic pollutants (POPs), AOPs have been developed that employ Fenton reactions promoted by ultrasound (US) or microwaves (MW). Integrated methods combining AOPs with biological treatments are also of great interest. The present paper describes such an integrated approach for the decontamination of water from nonylphenol (NP), a common pollutant that accumulates in aquatic organisms and is quite resistant to biodegradation. Polluted water (containing 1,000 ppm of NP) was sequentially subjected to a sonochemical Fenton reaction and biosorption by the filamentous fungus Paecilomyces lilacinus. Although these methods can be used separately, the sequential approach proved more advantageous. In 1 h the sonochemical oxidation, carried out in a 300 kHz US-reactor equipped with a cooling system, halved NP content in polluted water, as determined by GC-MS analysis. The water was then inoculated with pure cultures of the fungus, whose mycelial biomass further reduced NP content in 7 days. Thus an initial NP concentration of 1,000 ppm was reduced approximately by 90%. 相似文献
252.
Frédéric Simard Diego Ayala Guy Colince Kamdem Marco Pombi Joachim Etouna Kenji Ose Jean-Marie Fotsing Didier Fontenille Nora J Besansky Carlo Costantini 《BMC ecology》2009,9(1):17-24
Background
Speciation among members of the Anopheles gambiae complex is thought to be promoted by disruptive selection and ecological divergence acting on sets of adaptation genes protected from recombination by polymorphic paracentric chromosomal inversions. However, shared chromosomal polymorphisms between the M and S molecular forms of An. gambiae and insufficient information about their relationship with ecological divergence challenge this view. We used Geographic Information Systems, Ecological Niche Factor Analysis, and Bayesian multilocus genetic clustering to explore the nature and extent of ecological and chromosomal differentiation of M and S across all the biogeographic domains of Cameroon in Central Africa, in order to understand the role of chromosomal arrangements in ecological specialisation within and among molecular forms. 相似文献253.
Carlo Costantini Diego Ayala Wamdaogo M Guelbeogo Marco Pombi Corentin Y Some Imael HN Bassole Kenji Ose Jean-Marie Fotsing N'Falé Sagnon Didier Fontenille Nora J Besansky Frédéric Simard 《BMC ecology》2009,9(1):1-27
Background
Ongoing lineage splitting within the African malaria mosquito Anopheles gambiae is compatible with ecological speciation, the evolution of reproductive isolation by divergent natural selection acting on two populations exploiting alternative resources. Divergence between two molecular forms (M and S) identified by fixed differences in rDNA, and characterized by marked, although incomplete, reproductive isolation is occurring in West and Central Africa. To elucidate the role that ecology and geography play in speciation, we carried out a countrywide analysis of An. gambiae M and S habitat requirements, and that of their chromosomal variants, across Burkina Faso.Results
Maps of relative abundance by geostatistical interpolators produced a distinct pattern of distribution: the M-form dominated in the northernmost arid zones, the S-form in the more humid southern regions. Maps of habitat suitability, quantified by Ecological Niche Factor Analysis based on 15 eco-geographical variables revealed less contrast among forms. M was peculiar as it occurred proportionally more in habitat of marginal quality. Measures of ecological niche breadth and overlap confirmed the mismatch between the fundamental and realized patterns of habitat occupation: forms segregated more than expected from the extent of divergence of their environmental envelope – a signature of niche expansion. Classification of chromosomal arm 2R karyotypes by multilocus genetic clustering identified two clusters loosely corresponding to molecular forms, with 'mismatches' representing admixed individuals due to shared ancestral polymorphism and/or residual hybridization. In multivariate ordination space, these karyotypes plotted in habitat of more marginal quality compared to non-admixed, 'typical', karyotypes. The distribution of 'typical' karyotypes along the main eco-climatic gradient followed a consistent pattern within and between forms, indicating an adaptive role of inversions at this geographical scale.Conclusion
Ecological segregation between M and S is consistent with niche expansion into marginal habitats by chromosomal inversion variants during early lineage divergence; presumably, this process is promoted by inter-karyotype competition in the higher-quality core habitat. We propose that the appearance of favourable allelic combinations in other regions of suppressed recombination (e.g. pericentromeric portions defining speciation islands in An. gambiae) fosters development of reproductive isolation to protect linkage between separate chromosomal regions. 相似文献254.
Unmethylated CpG oligodeoxynucleotides activate head kidney leukocytes of Atlantic cod, <Emphasis Type="Italic">Gadus morhua</Emphasis> 总被引:1,自引:1,他引:0
Christopher Marlowe A. Caipang Sanchala Gallage Carlo C. Lazado Monica F. Brinchmann Viswanath Kiron 《Fish physiology and biochemistry》2010,36(4):1151-1158
Bacterial DNA and synthetic oligodeoxynucleotides (ODNs) that contain unmethylated CpG motifs are strong inducers of immune
response in most mammalian organisms. The use of these synthetic CpG motifs in fish, particularly in salmonids and carp, resulted
in the modulation of their immune system. However, much less is known in other species of fish such as gadoids including Atlantic
cod, Gadus morhua. Using head kidney (HK) leukocytes of cod in an in vitro study, we determined the effects of some established CpG-ODNs on
the cellular responses of the fish immunocytes. Incubation of the HK leukocytes with 2 μM concentration of the CpG-ODNs resulted
in enhanced respiratory burst. There were differential effects on the activities of acid phosphatase and cellular myeloperoxidase.
Only CpG-ODN 1826 triggered a significant increase in the level of both enzymes. On the other hand, the supernatants derived
from the HK leukocytes after incubation with different CpG-ODNs did not possess bactericidal activity against Vibrio anguillarum and Aeromonas salmonicida. This study has shown that CpG-ODNs at low concentrations are able to stimulate respiratory burst in cod but have minimal
effects on cellular enzymatic activities and antibacterial action. 相似文献
255.
Elisabetta B. Morello Bruno Antolini Maria Emilia Gramitto R. James A. Atkinson Carlo Froglia 《Fisheries Research》2009,95(2-3):325-331
The Norway lobster, Nephrops norvegicus, is mainly targeted by bottom trawlers whose selectivity (mesh size = 40 mm stretch) with respect to this species is poor producing large quantities of discards both in terms of demersal fish species and undersized Nephrops. The Pomo pit (central Adriatic Sea) is a very important nursery area for European hake, Merluccius merluccius, but is also the main trawling ground for the Adriatic fleet exploiting Nephrops. The use of baited creels may constitute an alternative to bottom trawling. This paper summarises experimental data collected from the western Pomo pit in order to compare bottom trawl and baited creel catches with the aim of evaluating the ecological consequences of creeling. Because of high scavenger activity in the area, the effect of this on the creel fishery was also investigated.A large fraction of the trawl catch was composed of juvenile undersized individuals of commercial species, the same was not true for creels. Composition of Nephrops catches differed markedly between creels and the bottom trawl. Scavenger activity was very high. The results indicate that ecologically the use of baited creels appears to be a valid alternative to bottom trawling but, unfortunately, may not comprise an economically viable solution in the investigated area, which is 30 nautical miles offshore. 相似文献
256.
257.
This study investigated the influences of two algal derivatives, alginic acid and fucoidan (FUC) on the activities of the intestinal epithelial cells (IEC) of Atlantic cod. The cells were isolated from three regions of the intestines, and primary cultures were incubated with the derivatives followed by temporal analysis of cellular activities. Epithelial cell survival in the fore and hind intestine was not significantly affected by the algal derivatives at both time points (3 and 24 h postincubation, hpi). Cellular survival in the mid‐intestine decreased significantly at 3 hpi. Stimulation of myeloperoxidase (MPO) activity of IEC induced by the algal derivatives was observed to be region dependent. Myeloperoxidase activity in the cells from fore‐ and mid‐intestines was not significantly affected by the two algal derivatives. Both algal derivatives significantly stimulated the activity at 3 hpi in the hind intestinal cells, and FUC‐exposed cells remained significantly elevated until 24 hpi. The results showed that algal derivatives could be applied as potential immunostimulants in cod with stimulatory action of MPO activity in the mucosal immune cells of the hind intestine. 相似文献
258.
Federica Bini Klaus Geider Carlo Bazzi 《European journal of plant pathology / European Foundation for Plant Pathology》2008,122(3):403-411
Tumour tissue samples were collected from vines grown in various regions of Italy and other parts of Europe and extracted
for detection of Agrobacterium vitis. Fifty strains were isolated on agar plates and screened by PCR with consensus primers from the virD2 gene. They were confirmed as A. vitis with a species-specific monoclonal antibody. The isolates were further analyzed by PCR for their opine synthase genes and
ordered into octopine, nopaline and vitopine strains. Primers designed on the octopine synthase gene did not detect octopine
strains of Agrobacterium tumefaciens. For quantitative PCR, virD2 fragments were sequenced: two classes of virD2 genes were found and two primer sets designed, which detected octopine and nopaline strains or only vitopine strains. For
simultaneous identification of all opine-type strains, multiplex real-time PCR with either primer pair and SYBR Green was
performed: the combined sets of primers gave signals with DNA from any A. vitis strain. Specificity of the new primers for real-time PCR was evaluated using several unidentified bacterial isolates from
grapevines and other plant species. An elevated level of non-specific background was observed when the combined primer sets
were used in multiplex PCR assays. The real-time PCR protocol was also used to detect A. vitis cells directly from grapevine tumours; avoiding direct isolation procedures a sensitivity in the range of one to ten cells
per assay was found. Inhibition of the PCR reaction by plant material was overcome by treating tumour extracts with a DNA
purification kit as a step for the isolation of nucleic acids. 相似文献
259.
Christopher Marlowe A. Caipang Effrosyni Fatira Carlo C. Lazado Michail Pavlidis 《Aquaculture International》2014,22(4):1283-1293
Juveniles of Atlantic cod, Gadus morhua L., weighing 30–50 g were subjected to short-term handling stress by exposing them to air for 3 min and immediately placing in the rearing tank for recovery. Indices for the primary stress response as well as selected immune- and metabolism-related parameters were measured in the plasma before the application of the stressor and at 1-h, 24-h and 7-day post-stress. Plasma cortisol significantly increased at 1-h post-stress then returned to the prestress levels at 24-h post-exposure. Plasma glucose and total antioxidant capacity had two peaks at 1 h and 7 days after handling stress. Alkaline phosphatase significantly increased at 24-h post-exposure, while no significant changes in myeloperoxidase activity was observed. Lysozyme and antiprotease activities were significantly downregulated at 1- and 24-h post-exposure, respectively. These findings showed that short-term handling stress in Atlantic cod juveniles resulted in temporal elevation of the primary stress response and metabolism with a corresponding decrease in its defense against bacterial pathogens. 相似文献
260.
Carlo L. Seifert Florian Bodner Gunnar Brehm Konrad Fiedler 《Journal of insect science (Online)》2015,15(1)
The very species-rich tropical moth genus Eois Hübner (Lepidoptera: Geometridae) is a promising model group for studying host plant specialization and adaptive radiation. While most Eois species are assumed to be specialized herbivores on Piper L. species, records on other plant taxa such as Peperomia Ruiz & Pavón (Piperaceae) are still relatively scarce. Moreover, little is known about life history traits of most species, and only a few caterpillars have been described so far. We collected caterpillars associated with Peperomia (Piperaceae) host plants from June 2012 to January 2013 in three elevational bands of montane and elfin rainforests on the eastern slopes of the Andes in southern Ecuador. Caterpillars were systematically searched and reared to the adult stage. We were able to delimitate ten species of Eois on Peperomia by comparison of larval and adult morphology and by using 658 bp fragments of the mitochondrial COI gene (barcode sequences). Three of these species, Eois albosignata (Dognin), Eois bolana (Dognin), and Eois chasca (Dognin), are validly described whereas the other seven taxa represent interim morphospecies, recognized unequivocally by their DNA barcodes, and their larval and adult morphology. We provide information about their host plants, degree of parasitism, and describe the larval stages in their last instar. Additionally, caterpillars and moths are illustrated in color plates. This is the first comparative study dealing with Eois moths whose caterpillars feed on Peperomia hosts. 相似文献