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111.
Andre Freire Cruz Bruno Ferreira de Oliveira Marcio de Carvalho Pires 《International Journal of Fruit Science》2017,17(3):259-268
An experiment under greenhouse conditions was carried out to evaluate the best level of nitrogen (N) and phosphorus (P), which promote the growth of papaya (Carica papaya L. var. Solo) seedlings without affecting the arbuscular mycorrhizal fungi (AMF) activity. Seedlings of papaya were transplanted to pots inoculated or not with Gigaspora margarita spores at four levels of N (0, 50, 100, and 200 ppm) and P (0, 25, 50, and 100 ppm). P was amended at the same time of pot filling up with substrate but N was applied weekly. The experiment was harvested after 100 days and plant dry weight together with AMF colonization was measured. The major response on the plant dry weight and height was from the fertilizers (N and P) where it proportionally increased. For the dry weight, at low amounts of nutrients the effects of AMF were greater, but as much as the fertilizer level in soil increased this response decreased. The colonization decreased as the nutrient levels increased, especially the P. The best combination of N and P for plant growth and AMF colonization could be at 50 and 25 ppm, equivalent to 5 and 2.5 kg/10a, respectively. 相似文献
112.
Takaaki Ishii Atsushi Matsumura Sachie Horii Hino Motosugi Andre Freire Cruz 《Biology and Fertility of Soils》2007,44(1):217-222
A greenhouse experiment was conducted to examine the favorable effects of sod culture system with bahiagrass (Paspalum notatum Flügge.) and Vulpia myuros (L.) C. C. Gmel. intercropped with citrus trees on the establishment of the network of arbuscular mycorrhizal (AM) fungus
hyphae in their rhizospheres. Special acrylic root boxes with three compartments were used for the experiment. Four types
of citrus rootstock seedlings, trifoliate orange (Poncirus trifoliata Raf.), sour orange (Citrus aurantium L.), rough lemon (Citrus jambhiri Lush.), and Citrus natsudaidai Hayata, were separately transplanted into one outer compartment in each box, and the seedlings of bahiagrass and V.myuros were separately transplanted into the other outer compartment. An AM fungus, Gigaspora margarita Becker and Hall, was inoculated in the center compartment of each box. Some boxes with both outer compartments without plants
and with some plants in only one outer compartment were also prepared. The box with bare × bare had very low density of AM
hyphae. There were a few hyphae in bare compartments in the boxes of trifoliate orange × bare, sour orange × bare, rough lemon
× bare, and C. natsudaidai × bare. The density of hyphae in the compartments with citrus seedlings and grasses, however, was significantly higher than
in every bare compartment, and the hyphae in the compartments with plants penetrated deeply into the sand. In particular,
the density in the compartments of citrus seedlings increased when bahiagrass or V. myuros was transplanted as a neighboring plant. The percentage of AM fungus colonization in every plant root was high. New spore
formation was observed in compartments with plants, whereas there were few spores in every bare compartment. In particular,
the spore formation in bahiagrass compartments was superior to that in other compartments with plants. Our results suggest
that the network system by AM hyphae is easily discernible in the rhizospheres between citrus rootstocks and bahiagrass or
V. myuros, but bare ground severely inhibits the formation and development of AM hyphal network and reduces the number of AM spores
in the soil. 相似文献
113.
Andre Shih DVM DACVA Herbert W. Maisenbacher DVM DACVIM Carsten Bandt DVM DACVECC Carolina Ricco DVM MS DACVA James Bailey DVM DACVA Jess Rivera BS Amara Estrada DVM DACVIM 《Journal of Veterinary Emergency and Critical Care》2011,21(4):321-327
Objective – To determine if metatarsal artery pressure (COmet) is comparable to femoral artery pressure (COfem) as the input for transpulmonary pulse contour analysis (PiCCO) in anesthetized dogs, using the lithium dilution method (LiDCO) as a standard for cardiac output (CO) measurement. Design – Prospective randomized study. Setting – University research laboratory. Animals – Ten healthy purpose‐bred mixed breed dogs were anesthetized and instrumented to measure direct blood pressure, heart rate, arterial blood gases, and CO. Interventions – The CO was measured using LiDCO and PiCCO techniques. Animals had their right femoral and left distal metatarsal artery catheterized for proximal (COfem) and distal (COmet) PiCCO analysis, respectively. Measurements were obtained from each animal during low, normal, and high CO states by changing amount of inhalant anesthetics and heart rate. Measurements were converted to CO indexed to body weigh (CIBW=CO/kg) for statistical analysis. Agreement was determined using Bland and Altman analysis and concordance correlation coefficients. Measurements and Main Results – Thirty paired measurements were taken. The LiDCO CIBW (± SD) was 68.7 ± 30.3, 176.0 ± 53.0, and 211.1 ± 76.5 mL/kg/min during low, normal, and high CO states, respectively. There was a significant effect of CIBW state on bias and relative bias with COmet (P<0.001 and P=0.003, respectively). Bias of the COmet method (± SD) was ?116.6 (70.5), 20.1(76.4), and 91.3 (92.0) mL/kg/min at low, normal, and high CIBW, respectively. Bias of the COfem (± SD) was ?20.3 (19.0), 8.6 (70.9), and ?2.9 (83.0) mL/kg/min at low, normal, and high CIBW, respectively. The mean relative bias for COfem was ?6.7 ± 44% (limits of agreements: ?81.2 to 67.9%). Conclusion – Compared with lithium dilution, the pulse contour analysis provides a good estimation of CO, but requires femoral artery catheterization in anesthetized dogs. 相似文献
114.
115.
Zhang K Wong JW Yang P Tech K Dibenedetto AL Lee NS Hayward DG Makovi CM Krynitsky AJ Banerjee K Jao L Dasgupta S Smoker MS Simonds R Schreiber A 《Journal of agricultural and food chemistry》2011,59(14):7636-7646
A multiresidue method analyzing 209 pesticides in 24 agricultural commodities has been developed and validated using the original Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) procedure and high performance liquid chromatography-positive electrospray ionization-tandem mass spectrometry (LC-MS/MS) analysis. Using solvent-only calibration standards (SOCSs) and matrix-matched calibration standards (MMCSs), it was demonstrated that a minimal concentration of 5-10 μg/kg (part per billion, ppb) of analytes in matrix is required for the consistent identification of targeted pesticides with two MRM transitions. Method performance was validated by the precision and accuracy results obtained from fortification studies at 10, 25, 100, and 500 ppb and MMCSs. The method was demonstrated to achieve an average recovery of 100 ± 20% (n = 4) for >75% of evaluated pesticides at the low fortification level (10 ppb) and improved to >84% at the higher fortification concentrations in all 24 matrices. Matrix effects in LC-MS/MS analysis were studied by evaluating the slope ratios of calibration curves (1.0-100 ng/mL) obtained from the SOCSs and MMCSs. Principal component analysis (PCA) of LC-MS/MS and method validation data confirmed that each matrix exerts its specific effect during the sample preparation and LC-MS/MS analysis. The matrix effect is primarily dependent on the matrix type, pesticide type and concentration. Some caution is warranted when using matrix matched calibration curves for the quantitation of pesticides to alleviate concerns on matrix effects. The QuEChERS method with LC-MS/MS was used to identify and quantitate pesticides residues, with concentrations ranging from 2.5 to >1000 ppb in a variety of agricultural samples, demonstrating fitness for screening and surveillance applications. 相似文献
116.
Gordon A Jungfer E da Silva BA Maia JG Marx F 《Journal of agricultural and food chemistry》2011,59(14):7688-7699
The Amazon region comprises a plethora of fruit-bearing species of which a large number are still agriculturally unimportant. Because fruit consumption has been attributed to an enhanced physical well-being, interest in the knowledge of the chemical composition of underexplored exotic fruits has increased during recent years. This paper provides a comprehensive identification of the polyphenolic constituents of four underutilized fruits from the Amazon region by HPLC/DAD-ESI-MS(n). Arac?a? ( Psidium guineense ), jambola?o ( Syzygium cumini ), muruci ( Byrsonima crassifolia ), and cutite ( Pouteria macrophylla ) turned out to be primarily good sources of hydrolyzable tannins and/or flavonols. Additionally, different flavanonols and proanthocyanidins were identified in some fruits. The antioxidant capacity was determined by using the total oxidant scavenging capacity (TOSC) assay. Cutite showed the highest antioxidant capacity followed by jambola?o, arac?a?, and muruci. 相似文献
117.
Kasparian J Rodriguez M Méjean G Yu J Salmon E Wille H Bourayou R Frey S Andre YB Mysyrowicz A Sauerbrey R Wolf JP Wöste L 《Science (New York, N.Y.)》2003,301(5629):61-64
Most long-path remote spectroscopic studies of the atmosphere rely on ambient light or narrow-band lasers. High-power femtosecond laser pulses have been found to propagate in the atmosphere as dynamically self-guided filaments that emit in a continuum from the ultraviolet to the infrared. This white light exhibits a directional behavior with enhanced backward scattering and was detected from an altitude of more than 20 kilometers. This light source opens the way to white-light and nonlinear light detection and ranging applications for atmospheric trace-gas remote sensing or remote identification of aerosols. Air ionization inside the filaments also opens promising perspectives for laser-induced condensation and lightning control. The mobile femtosecond-terawatt laser system, Teramobile, has been constructed to study these applications. 相似文献
118.
Yu F Hill RS Schaffner SF Sabeti PC Wang ET Mignault AA Ferland RJ Moyzis RK Walsh CA Reich D 《Science (New York, N.Y.)》2007,316(5823):370
Mekel-Bobrov et al. (Reports, 9 September 2005, p. 1720) suggested that ASPM, a gene associated with microcephaly, underwent natural selection within the last 500 to 14,100 years. Their analyses based on comparison with computer simulations indicated that ASPM had an unusual pattern of variation. However, when we compare ASPM empirically to a large number of other loci, its variation is not unusual and does not support selection. 相似文献
119.
120.
Sophie St-Hilaire Craig Sheppard Jeffery K . Tomberlin Stephen Irving Larry Newton Mark A . McGuire Erin E . Mosley Ronald W . Hardy Wendy Sealey 《Journal of the World Aquaculture Society》2007,38(1):59-67
Fly larvae may provide an effective method to mitigate two large and growing global concerns: the use of fish meal derived from capture fisheries in aquaculture diets and manure management in livestock and poultry facilities. A 9‐wk feed trial was conducted to determine whether fly larvae could be used as a partial fish meal and fish oil replacement in rainbow trout, Oncorhynchus mykiss, diets. A trout diet was formulated to contain 40% crude protein and 15% fat. Sixty‐seven percent of the protein in the control diet was derived from fish meal, and all the fat was derived from fish oil. Two of the test diets included using the black soldier fly, Hermetia illucens, prepupae, which are 40% protein and 30% fat, as 25 and 50% replacement for the fish meal component of the control diet. The total protein derived from black soldier fly prepupae in these two test diets was 15 and 34%, respectively. A third test diet included using housefly, Musca domestica, pupae, which is 70% protein and 16% fat, as 25% replacement for the fish meal component of the control diet. Data suggest that a rainbow trout diet where black soldier fly prepupae or housefly pupae constitute 15% of the total protein has no adverse effect on the feed conversion ratio of fish over a 9‐wk feeding period. In addition, the diet with black soldier fly prepupae permitted a 38% reduction in fish oil (i.e., from 13 to 8%); however, fish fed black soldier fly diets low in fish oil had reduced levels of omega‐3 fatty acids in their muscle fillets. The findings from this study suggest that either the black soldier fly or the housefly may be a suitable feedstuff for rainbow trout diets. 相似文献