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We investigate the influence of individual components and synergistic mixtures of the surface-active substances with inorganic passivator on the electrochemical and corrosion behaviors of steel in neutral aqueous salt solutions. T...
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We investigate the influence of individual components and synergistic mixtures of the surface-active substances with inorganic passivator on the electrochemical and corrosion behaviors of steel in neutral aqueous salt solutions. The character of relationship between the ratio of the concentrations of components of the compositions in the corrosive medium and their influence on the electrochemical and corrosion behaviors of the metals (isomolar series) is established. It is also demonstrated that, for the synergistic maxima the inhibition of the anodic reaction of ionization of the metals is especially pronounced the changes in the parameters of their passive state (corrosion potential, current density of complete passivation, and pitting potential) are maximum. In this case, the corrosion protection of steel becomes practically complete.
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This paper is about the construction of a family of centrally synergistic potential functions from a single modified trace function on SO(3). First, we demonstrate that it is possible to complete the construction through angular w...
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This paper is about the construction of a family of centrally synergistic potential functions from a single modified trace function on SO(3). First, we demonstrate that it is possible to complete the construction through angular warping with multiple directions, particularly effective in the unresolved cases in the literature. Second, it can be shown that for each potential function in the family, there exists a subset of the family such that the synergistic gap is positive at the unwanted critical points. This allows the switching condition to be checked within the selected subsets while implementing synergistic hybrid control. Furthermore, the positive lower bound of synergistic gap is explicitly expressed by selecting a traditional warping angle function. Finally, we apply the proposed synergistic potential functions to obtain robust global attitude tracking.
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Growth and Differentiation Factor 1 (GDF-1) has been implicated in left-right patterning of the mouse embryo but has no other known function. Here, we demonstrate a genetic interaction between Gdf1 and Nodal during anterior axis d...
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Growth and Differentiation Factor 1 (GDF-1) has been implicated in left-right patterning of the mouse embryo but has no other known function. Here, we demonstrate a genetic interaction between Gdf1 and Nodal during anterior axis development. Gdf1(-/-);Nodal(+/-) mutants displayed several abnormalities that were not present in either Gdf1(-/-) or Nodal(+/-) single mutants, including absence of notochord and prechordal plate, and malformation of the foregut; organizing centers implicated in the development of the anterior head and branchial arches, respectively. Consistent with these deficits, Gdf1(-/-);Nodal(+/-) mutant embryos displayed a number of axial midline abnormalities, including holoprosencephaly, anterior head truncation, cleft lip, fused nasal cavity, and lack of jaws and tongue. The absence of these defects in single mutants indicated a synergistic interaction between Nodal and GDF-1 in the node, from which the axial mesendoderm that gives rise to the notochord, prechordal plate, and foregut endoderm originates, and where the two factors are co-expressed. This notion was supported by a severe downregulation of FoxA2 and goosecoid in the anterior primitive streak of double mutant embryos. Unlike that in the lateral plate mesoderm, Nodal expression in the node was independent of GDF-1, indicating that both factors act in parallel to control the development of mesendodermal precursors. Receptor reconstitution experiments indicated that GDF-1, like Nodal, can signal through the type I receptors ALK4 and ALK7. However, analysis of compound mutants indicated that ALK4, but not ALK7, was responsible for the effects of GDF-1 and Nodal during anterior axis development. These results indicate that GDF-1 and Nodal converge on ALK4 in the anterior primitive streak to control the formation of organizing centers that are necessary for normal forebrain and branchial arch development. (c) 2006 Elsevier Inc. All rights reserved.
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The presence of root-knot nematode, Meloidogyne incognita was assessed on roots and rhizosphere soil of cock's comb (Celosia argentea L.) planted in 5 lawns located at the campus of University of Agriculture, Faisalabad. The infec...
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The presence of root-knot nematode, Meloidogyne incognita was assessed on roots and rhizosphere soil of cock's comb (Celosia argentea L.) planted in 5 lawns located at the campus of University of Agriculture, Faisalabad. The infected plants were stunted with galled and rotted roots. Four fungal pathogens including Fusarium, Pythium, Rhizoctonia and Sclerotia were isolated from nematode-fungal complex infected roots. Plant parasitic nematodes belonging to eight genera in addition to M. incognita were also found in root and soil samples. The number of root-galling, egg-masses, galling and egg-mass indices and J(2) Population on plants were variable among the lawns. They were highest in samples collected from extension and education division, intermediate in that of club rest house and lowest in that of dean faculty of agriculture, old campus and dean faculty of animal science. The mixed infection of roots by nematodes and fungi suggests that plant damage might be due to synergistic relationship of nematode and fungi, which needs further investigations to prove this relationship.
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Catala-Gregori, P., Mallet, S., Travel, A., Orengo, J. and Lessire, M. 2008. Efficiency of a prebiotic and a plant extract alone or in combination on broiler performance and intestinal physiology. Can. J. Anim. Sci. 88: 623-629. A...
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Catala-Gregori, P., Mallet, S., Travel, A., Orengo, J. and Lessire, M. 2008. Efficiency of a prebiotic and a plant extract alone or in combination on broiler performance and intestinal physiology. Can. J. Anim. Sci. 88: 623-629. A 36-d trial was conducted to evaluate two potential alternatives to antibiotic growth promoters in broilers. The products tested were a prebiotic (PROFEED (R)) and a plant extract (XTRACT (TM)). Ross mate broiler performance and digestive tract function responses were studied. To evaluate the effect of these potential alternatives alone or in combination, seven diets were tested: positive control avilamycin 10 ppm (PC);negative control antibiotic-free (NC); NC+PROFEED (R) 600 ppm (P); NC+XTRACT (TM) 100 ppm (X); NC+PROFEED (R)/XTRACT (TM) 600/100 ppm (XPH); NC+PROFEED (R)/XTRACT (TM) 450/75 ppm (XPM); NC+PROFEED (R)/XTRACT (TM) 300/50 ppm (XPL). From 22 to 36 d of age, body weight gain (BWG) was improved by P, X, and XPM compared with NC (P < 0.05). Throughout the trial, broilers fed PC, P, X and XPL had a better feed conversion ratio (FCR) than those fed NC (P < 0.1). No relevant negative effect was observed for the parameters relative to the digestive tract function:ileal histomorphometry, anaerobic sulphite-reducing bacteria count (ASR), intestinal and caecal pH, caecal volatile fatty acids production (VFA) and litter score (LS). With the higher mixture dose (XPH), no improvement in broiler performance was observed, suggesting no synergistic effect of the two additives.
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In Brazil, Meloidogyne mayaguensis has become a threat to guava production. Approximately a third of the cultivated area is infested, leading almost inevitably to the decimation of the orchards. Because parasitized trees develop r...
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In Brazil, Meloidogyne mayaguensis has become a threat to guava production. Approximately a third of the cultivated area is infested, leading almost inevitably to the decimation of the orchards. Because parasitized trees develop rotten roots as the disease progresses, the possibility that a soil-borne pathogen could be involved was investigated. From several nematode-free or nematode-infested orchards, nearly 2000 root fragments were tested for bacteria and fungi. Positive isolations were obtained from nematode-infested areas only and were predominantly identified as Fusarium sp. In a 5-month microplot experiment, guava seedlings were uninoculated (control) or were inoculated with M. mayaguensis only or with this nematode and 21 days later with one of 11 Fusarium sp. isolates. A Scott-Knot analysis of several vegetative variables and of the extent of root rot allowed the generation of a dissimilarity dendrogram that indicated that four Fusarium sp. isolates were particularly associated with damage to the seedlings. Upon identification of these isolates as Fusarium solani, a 6-month microplot experiment was set up, in which guava seedlings were uninoculated or were inoculated with one of the following: (i) M. mayaguensis only, (ii) four F. solani isolates, separately, (iii) four F. solani isolates separately, combined with physical injury of the roots with a knife, (iv) M. mayaguensis, and 21 days later with four F. solani isolates, separately. No root rot and virtually no effect on all variables were observed in the seedlings inoculated with the fungus isolates, with or without physical injury. Major root rot and a negative effect on all variables were observed in the seedlings inoculated with M. mayaguensis and all four F. solani isolates. This characterizes guava decline as a complex disease caused by the synergistic effect of these organisms, in which parasitism by the nematode predisposes the plants to root decay caused by the fungus.
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In Brazil, Meloidogyne mayaguensis has become a threat to guava production. Approximately a third of the cultivated area is infested, leading almost inevitably to the decimation of the orchards. Because parasitized trees develop r...
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In Brazil, Meloidogyne mayaguensis has become a threat to guava production. Approximately a third of the cultivated area is infested, leading almost inevitably to the decimation of the orchards. Because parasitized trees develop rotten roots as the disease progresses, the possibility that a soil-borne pathogen could be involved was investigated. From several nematode-free or nematode-infested orchards, nearly 2000 root fragments were tested for bacteria and fungi. Positive isolations were obtained from nematode-infested areas only and were predominantly identified as Fusarium sp. In a 5-month microplot experiment, guava seedlings were uninoculated (control) or were inoculated with M. mayaguensis only or with this nematode and 21 days later with one of 11 Fusarium sp. isolates. A Scott-Knot analysis of several vegetative variables and of the extent of root rot allowed the generation of a dissimilarity dendrogram that indicated that four Fusarium sp. isolates were particularly associated with damage to the seedlings. Upon identification of these isolates as Fusarium solani, a 6-month microplot experiment was set up, in which guava seedlings were uninoculated or were inoculated with one of the following: (i) M. mayaguensis only, (ii) four F. solani isolates, separately, (iii) four F. solani isolates separately, combined with physical injury of the roots with a knife, (iv) M. mayaguensis, and 21 days later with four F. solani isolates, separately. No root rot and virtually no effect on all variables were observed in the seedlings inoculated with the fungus isolates, with or without physical injury. Major root rot and a negative effect on all variables were observed in the seedlings inoculated with M. mayaguensis and all four F. solani isolates. This characterizes guava decline as a complex disease caused by the synergistic effect of these organisms, in which parasitism by the nematode predisposes the plants to root decay caused by the fungus.
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Aim:To select a toxin combination for the management of maize stem borer (Chilo partellus) and to understand possible mechanism of synergism among Bacillus thuringiensis Cry1A toxins tested.Methods and Results:Three Cry1A toxins w...
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Aim:To select a toxin combination for the management of maize stem borer (Chilo partellus) and to understand possible mechanism of synergism among Bacillus thuringiensis Cry1A toxins tested.Methods and Results:Three Cry1A toxins were over expressed in Escherichia coli strain JM105 and used for diet overlay insect bioassay against C. partellus neonate larvae, both alone and in combinations. Probit analysis revealed that the three Cry1A toxins tested have synergistic effect against C. partellus larvae. In vitro binding analysis of fluorescein isothiocyanate (FITC)-labelled Cry1A toxins to midgut brush border membrane vesicle (BBMV) shows that increase in toxicity is directly correlated to an increase in binding of toxin mix.Conclusions:A high Cry1Ac to Cry1Ab ratio leads to an increase in efficacy of these toxins towards C. partellus larvae and this increase in toxicity comes from an increase in toxin binding.Significance and Impact of the Study:Use of Cry1Ab and Cry1Ac combination could be an effective approach to control C. partellus. Furthermore, we show it first time that possible reason behind increase in toxicity of synergistic Cry1A proteins is an increase in toxin binding.
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The survival and infectivity of the infective juveniles of two species of entomopathogenic nematodes, Steinernema feltiae (Rhabditida: Steinernematidae) Heterorhabditis bacteriophora (Rhabditida: Heterorhabditidae), were determine...
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The survival and infectivity of the infective juveniles of two species of entomopathogenic nematodes, Steinernema feltiae (Rhabditida: Steinernematidae) Heterorhabditis bacteriophora (Rhabditida: Heterorhabditidae), were determined after exposure for 72 h to two concentrations of the herbicides glyphosate and MCPA, as well as to the combination of the two herbicides (glyphosate + MCPA). For all herbicide treatments, concentrations and exposure times, S. feltiae was more tolerant to the herbicides than H. bacteriophora. The exposure of entomopathogenic nematodes to glyphosate + MCPA caused significantly higher mortality (26.33-57.33%) than glyphosate (0.67-15%) or MCPA (2.33-19%) alone. These results confirm the synergistic effect of the glyphosate + MCPA combination on the mortality in these nematodes. Nematode infectivity of Galleria mellonella larvae in response to the herbicides presence was evaluated in Petri dish assays containing sterile sand. Nematode infectivity was not significantly reduced by exposure to herbicides in S. feltiae but H. bacteriophora was less tolerant. Synergistic effect was obtained in the nematode mortality test but no synergistic effect was observed in the nematode infectivity assay. Our results suggest that possible synergistic effects of agrochemicals on survival of nematodes should be tested before mixing with entomopathogenic nematodes.
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lndoxacarb was treated to Plutella xylostella for 10 generations to develop a resistant strain and biochemical analysis of indoxacarb resistance in different tissues of P. xylostella was carried out. Biochemical analysis found max...
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lndoxacarb was treated to Plutella xylostella for 10 generations to develop a resistant strain and biochemical analysis of indoxacarb resistance in different tissues of P. xylostella was carried out. Biochemical analysis found maximum esterase activity in gut homogenates of indoxacarb resistant strains followed by whole body and cuticle homogenates. In gut homogenates of indoxacarb resistant strains, maximum increase in esterases was found as compared to the unselected strain. Acetylcholineesterase activity was higher in head homogenates of the resistant strain than in the unselected strain. Glutathione-S-transferase activity was highest in whole body homogenates. However, maximum increase was found in gut homogenates of indoxacarb resistant strains over the unselected. Induced resistance was suppressed using known synergists. Maximum synergism occurred using diethyl-maleate (DEM), followed by triphenyl phosphate (TPP).
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