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991.
Willian Rogers Ferreira de Camargo Nícholas Ferreira de Camargo Danilo do Carmo Vieira Corrêa Amabílio J. Aires de Camargo Ivone Rezende Diniz 《Journal of insect science (Online)》2015,15(1)
Sexual dimorphism is a pronounced pattern of intraspecific variation in Lepidoptera. However, moths of the family Sphingidae (Lepidoptera: Bombycoidea) are considered exceptions to this rule. We used geometric morphometric techniques to detect shape and size sexual dimorphism in the fore and hindwings of seven hawkmoth species. The shape variables produced were then subjected to a discriminant analysis. The allometric effects were measured with a simple regression between the canonical variables and the centroid size. We also used the normalized residuals to assess the nonallometric component of shape variation with a t-test. The deformations in wing shape between sexes per species were assessed with a regression between the nonreduced shape variables and the residuals. We found sexual dimorphism in both wings in all analyzed species, and that the allometric effects were responsible for much of the wing shape variation between the sexes. However, when we removed the size effects, we observed shape sexual dimorphism. It is very common for females to be larger than males in Lepidoptera, so it is expected that the shape of structures such as wings suffers deformations in order to preserve their function. However, sources of variation other than allometry could be a reflection of different reproductive flight behavior (long flights in search for sexual mates in males, and flight in search for host plants in females). 相似文献
992.
Diana E. Adame-Castro Deb R. Aryal Gilberto Villanueva-López Jorge O. López-Martínez Alfonso J. Chay-Canul Fernando Casanova-Lugo 《Soil Use and Management》2020,36(4):671-681
This study aimed to quantify the dynamics of soil CO2 fluxes in two silvopastoral systems based on Leucaena leucocephala, one associated with Panicum maximum (L + P) and another with Cynodon plectostachyus (L + C). We measured CO2 fluxes fortnightly during the dry and rainy seasons in the morning and the afternoon, with an infrared gas analyzer. Simultaneously, we measured soil temperature, soil moisture, ambient temperature, and relative humidity. Soil CO2 fluxes ranged from 6.0 ± 0.14 to 6.1 ± 0.12 µmol CO2/m2/s but no statistical differences were observed between systems. Soil CO2 flux in the L + P was 12.5% higher in the rainy season compared with the dry season but the season did not affect the fluxes in L + C. Regarding the diurnal variation, CO2 fluxes were 17.6%–34.8% higher in the morning compared with afternoon measurements. Soil moisture and temperature were higher in L + C, but the ambient temperature and relative humidity showed no statistical differences between systems. In both systems, soil temperature was greater in the afternoon, while the soil moisture and relative humidity were greater in the morning. The diurnal variation of soil CO2 fluxes in silvopastoral systems correlated positively with soil temperature and ambient temperature, but negatively with relative humidity. We concluded that soil CO2 fluxes did not vary between silvopastoral systems but respond differently to the seasons. The results have important implications on the establishment and management of Leucaena-based silvopastoral systems for the mitigation of soil CO2 fluxes from extensive livestock production lands. 相似文献
993.
Dietary Oil Sources on the Innate Immunity and Resistance of Nile Tilapia,Oreochromis niloticus,to Streptococcus agalactiae Challenge
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Milena W. Ferreira Diego V. da Costa Carlos A. G. Leal Henrique C. P. Figueiredo Priscila V. Rosa 《Journal of the World Aquaculture Society》2015,46(3):252-262
The effect of different dietary oil sources on the innate immunity and resistance of Nile tilapia, Oreochromis niloticus, to Streptococcus agalactiae infection were evaluated. Fish were fed with diets containing different lipid sources (soybean oil [SO], corn oil, linseed oil [LO], fish oil [FO], and olive oil [OO]). Fish fed SO presented the highest (P < 0.05) hematocrit and serum protein. LO and FO diets increased (P < 0.05) the erythrocyte resistance to osmotic lysis in comparison with other treatments. Fish fed OO showed the highest (P < 0.05) iron‐binding capacity and the lowest serum lysozyme and bactericidal activities (P < 0.05). No difference (P > 0.05) was found between diets in alternative complement activity. Fish fed the SO diet had the highest (P < 0.05) survival rate against S. agalactiae challenge. In conclusion, diets with LO oil and FO, rich in ω‐3 fatty acids, and OO, rich in ω‐9 fatty acids, have an immunomodulatory effect in Nile tilapia juveniles. The use of SO in the Nile tilapia diet improved immune function and resistance against S. agalactiae. 相似文献
994.
Pollyanna de Moraes Frana Ferreira Lidiane da Silva Nascimento Devlynn Coelho Dias Diogo Magalhes da Veiga Moreira Ana Lúcia Salaro Mariella Bontempo Duca de Freitas Antonio Policarpo Souza Carneiro Jener Alexandre Sampaio Zuanon 《Journal of the World Aquaculture Society》2014,45(1):28-34
This study aimed to evaluate the potential of oregano oil as a growth promoter for the yellowtail tetra, Astyanax altiparanae. The fish (1.46 ± 0.09 g) were distributed into twenty‐four 60‐L aquaria at a stocking density of 0.5 fish/L. Six isonitrogenous (350 g crude protein/kg) and isocaloric (4272 kcal gross energy/kg) diets containing 0.0, 0.5, 1.0, 1.5, 2.0 and 2.5 g/kg of oregano oil were evaluated. At the end of 90 d there was a quadratic effect of oregano oil levels for weight gain, specific growth rate, protein efficiency ratio and carcass weight, and the estimated values to maximize these variables were between 0.2 and 0.6 g/kg. There was also a quadratic effect on the feed conversion ratio, and the estimated value to improve this variable was 0.62 g/kg. A positive linear effect of the treatments was observed for muscle glycogen. With increased levels of oregano oil in the diet, there was a reduction in dry matter and ether extract and an increase in the protein content of the carcass. Thus, it can be concluded that oregano oil, at the level of 0.5 g/kg, acts as a growth promoter for A. altiparanae by improving growth performance and carcass composition. 相似文献
995.
996.
Verza SG Silveira F Cibulski S Kaiser S Ferreira F Gosmann G Roehe PM Ortega GG 《Journal of agricultural and food chemistry》2012,60(12):3113-3118
The adjuvant activity of Chenopodium quinoa (quinoa) saponins on the humoral and cellular immune responses of mice subcutaneously immunized with ovalbumin (OVA) was evaluated. Two quinoa saponin fractions were obtained, FQ70 and FQ90, and 10 saponins were determined by UPLC/Q-TOF-MS. Mice were immunized subcutaneously with OVA alone or adjuvanted with Quil A (adjuvant control), FQ70, or FQ90. FQ70 and FQ90 significantly enhanced the amount of anti-OVA-specific antibodies in serum (IgG, IgG1, and IgG2b) in immunized mice. The adjuvant effect of FQ70 was significantly greater than that of FQ90. However, delayed type hypersensitivity responses were higher in mice immunized with OVA adjuvanted with FQ90 than mice treated with FQ70. Concanavalin A (Con A)-, lipopolysaccharide-, and OVA-stimulated splenocyte proliferation were measured, and FQ90 significantly enhanced the Con A-induced splenocyte proliferation. The results suggested that the two quinoa saponin fractions enhanced significantly the production of humoral and cellular immune responses to OVA in mice. 相似文献
997.
Sánchez-Patán F Tabasco R Monagas M Requena T Peláez C Moreno-Arribas MV Bartolomé B 《Journal of agricultural and food chemistry》2012,60(29):7142-7151
Lactobacillus plantarum IFPL935 was incubated with individual monomeric flavan-3-ols and dimeric A- and B-type procyanidins to identify new metabolites and to determine the effect of compound structural features on bacterial growth and catabolism. Complex extracts rich in A-type proanthocyanidins and phenolic acids from cranberry were also tested. The results showed that L. plantarum IFPL935 exhibited higher resistance to nongalloylated monomeric flavan-3-ols, A-type dimeric procyanidins, and cranberry extract than to (-)-epicatechin-3-O-gallate and B-type dimeric procyanidins. Despite these findings, the strain was capable of rapidly degrading (-)-epicatechin-3-O-gallate, but not A- or B-type dimeric procyanidins. However, it was able to produce large changes in the phenolic profile of the cranberry extract mainly due to the catabolism of hydroxycinnamic and hydroxybenzoic acids. Of most relevance was the fact that L. plantarum IFPL935 cleaved the heterocyclic ring of monomeric flavan-3-ols, giving rise to 1-(3',4'-dihydroxyphenyl)-3-(2″,4″,6″-trihydroxyphenyl)propan-2-ol, activity exhibited by only a few human intestinal bacteria. 相似文献
998.
Ubeda C San-Juan F Concejero B Callejón RM Troncoso AM Morales ML Ferreira V Hernández-Orte P 《Journal of agricultural and food chemistry》2012,60(24):6095-6102
This paper reports the determination of glycosidically bound aroma compounds and the olfactometric analysis in four strawberry varieties (Fuentepina, Camarosa, Candonga and Sabrina). Different hydrolytic strategies were also studied. The results showed significant differences between acid and enzymatic hydrolysis. In general terms, the greater the duration of acid hydrolysis, the higher was the content of norisoprenoids, volatile phenols, benzenes, lactones, Furaneol, and mesifurane. A total of 51 aglycones were identified, 38 of them unreported in strawberry. Olfactometric analyses revealed that the odorants with higher modified frequencies were Furaneol, γ-decalactone, ethyl butanoate, ethyl hexanoate, ethyl 3-methylbutanoate, diacetyl, hexanoic acid, and (Z)-1,5-octadien-3-one. This last compound, described as geranium/green/pepper/lettuce (linear retention index = 1378), was identified for the first time. Differences with regard to fruity, sweet, floral, and green aroma characters were observed among varieties. In Candonga and Fuentepina, the green character overpowered the sweet. In the other two strawberry varieties sweet attributes were stronger than the rest. 相似文献
999.
Iñiguez-Franco F Soto-Valdez H Peralta E Ayala-Zavala JF Auras R Gámez-Meza N 《Journal of agricultural and food chemistry》2012,60(26):6515-6523
Active membranes and food packaging containing antioxidants like catechin and epicatechin, combined with the use of materials made of biopolymers obtained from renewable sources, could create a novel alternative to reduce oxidation in food, pharmaceutical, and cosmetic products. Poly(94% L-lactic acid) films containing 1.28% catechin and 1.50% epicatechin were extruded in a pilot plant-scale extrusion machine. The diffusion kinetics of catechin and epicatechin into 95% ethanol at 20, 30, 40, and 50 °C and 50% ethanol at 40 °C displayed Fickian release behavior and diffusion coefficients between 0.5 and 50 × 10(-11) cm(2)/s. According to the Arrhenius equation, the energy of activation for the diffusion of catechin and epicatechin in the films was 110.43 and 98.92 kJ/mol, respectively. The antioxidant activity of the films was measured in methanol extracts containing 46.42 μg/mL of catechin and 57.52 μg/mL of epicatechin as 32.90 and 36.68% of scavenging the 2,2-diphenyl-1-picrylhydrazyl radical, respectively. 相似文献
1000.
M Carocho JC Barreira AL Antonio A Bento I Kaluska IC Ferreira 《Journal of agricultural and food chemistry》2012,60(31):7754-7760
Chestnuts are a widely consumed fruit around the world, with Portugal being the fourth biggest producer in Europe. Storage of these nuts is an important step during processing, and the most widely used fumigant was banned in the European Union under the Montreal Protocol because of its toxicity. Recently, radiation has been introduced as a cheap and clean conservation method. Previous studies of our research group proved that γ radiation had no negative effect on the nutritional value of chestnuts; in fact, storage time had a much bigger influence on the chestnut quality. In the present study, we report the effect of a less ionizing radiation, electron beam, with doses of 0, 0.5, 1, 3, and 6 kGy in the nutritional value of chestnuts (ash, energy, fatty acids, sugars, and tocopherols), previously stored at 4 °C for 0, 30, and 60 days. The storage time seemed to reduce fat and energetic values but reported a tendency for higher values of dry matter. With regard to fatty acids, there was a higher detected quantity of C20:2 in non-irradiated samples and four fatty acids were only detected in trace quantities (C6:0, C8:0, C10:0, and C12:0). γ-Tocopherol decreased during storage time but did not alter its quantity for all of the radiation doses (as like α-, β-, and δ-tocopherol); in fact, these compounds were present in higher concentrations in the irradiated samples. Sucrose and total sugars were lower in non-irradiated samples, and raffinose was only detected in irradiated samples. Electron-beam irradiation seems to be a suitable methodology, because the effects on chemical and nutritional composition are very low, while storage time seems to be quite important in chestnut deterioration. 相似文献