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101.
Wagner de Souza Tavares Ivan Cruz Fernando Petacci Sebastio Loureno de Assis Júnior Silvia de Sousa Freitas Jos Cola Zanuncio Jos Eduardo Serro 《Industrial Crops and Products》2009,30(3):384-388
Extracts of 12 Asteraceae were tested on Spodoptera frugiperda (Lepidoptera: Noctuidae) and on their parasitoids Telenomus remus (Hymenoptera: Scelionidae) and Trichogramma pretiosum (Hymenoptera: Trichogrammatidae). The plants Lychnophora ericoides and Trichogonia villosa were toxic for 97.7 ± 0.15% of one-day-old eggs of S. frugiperda and Lepidaploa lilacina for 72.0 ± 2.50% for two-day-old eggs of this insect. Extracts of Vernonia holosenicea, Lychnophora ramosissima and Chromolaena chaseae had higher impact on S. frugiperda, while those of Eremanthus elaeagnus and L. ericoides were more selective to T. pretiosum and T. remus. Asteraceae extracts present potential for integrated pest management programs of S. frugiperda. 相似文献
102.
R. M. Simeão G. M. L. Assis D. B. Montagner R. C. U. Ferreira 《Grass and Forage Science》2017,72(2):322-332
Forage peanut improvement for use in grass–legume mixtures is expected to have a great impact on the sustainability of Brazilian livestock production. Eighteen cloned Arachis spp. ecotypes were evaluated under clipping in a Brazilian Cerrado region and results analysed using a mixed model methodology. The objective was to estimate genetic and phenotypic parameters and to select the best ecotypes based on selection index applied on their predicted genotypic value. The traits of total dry‐matter (DM) and leaf DM yield presented moderate (0·30 < < 0·50) to high (>0·50) broad‐sense heritability, in contrast to the low genetic variability in nutritional quality‐associated traits. Ecotypes of Arachis spp. contained average crude protein concentrations of 224 g kg?1 DM in leaves and 138 g kg?1 DM in stems, supporting the potential role of these species to overcome the low protein content in Cerrado pastures. The correlations between yield traits and traits associated with low nutritional value in leaves were consistently significant and positive. Genetic correlations among all the yield traits evaluated during the rainy or dry seasons were significant and positive. The ecotypes were ranked based on selection index. The next step is to validate long‐term selection of grass–Arachis in combination with pastures under competition and adjusted grazing in the Cerrado region. 相似文献
103.
Pierre Auger Collaboration Abraham J Abreu P Aglietta M Aguirre C Allard D Allekotte I Allen J Allison P Alvarez C Alvarez-Muñiz J Ambrosio M Anchordoqui L Andringa S Anzalone A Aramo C Argirò S Arisaka K Armengaud E Arneodo F Arqueros F Asch T Asorey H Assis P Atulugama BS Aublin J Ave M Avila G Bäcker T Badagnani D Barbosa AF Barnhill D Barroso SL Bauleo P Beatty J Beau T Becker BR Becker KH Bellido JA Benzvi S Berat C Bergmann T Bernardini P Bertou X Biermann PL Billoir P Blanch-Bigas O 《Science (New York, N.Y.)》2007,318(5852):938-943
Using data collected at the Pierre Auger Observatory during the past 3.7 years, we demonstrated a correlation between the arrival directions of cosmic rays with energy above 6 x 10(19) electron volts and the positions of active galactic nuclei (AGN) lying within approximately 75 megaparsecs. We rejected the hypothesis of an isotropic distribution of these cosmic rays with at least a 99% confidence level from a prescribed a priori test. The correlation we observed is compatible with the hypothesis that the highest-energy particles originate from nearby extragalactic sources whose flux has not been substantially reduced by interaction with the cosmic background radiation. AGN or objects having a similar spatial distribution are possible sources. 相似文献
104.
Philip D. Koblik DVM MS Chi-Kwan Yen MD Jan Komtebedde DVM William J. Hornof DVM MS Peter F. Moore BvSc PhD Paul E. Fisher MS 《Veterinary radiology & ultrasound》1990,31(4):170-174
Shunt fraction was determined using transcolonic 123 I-iodoamphetamine (IMP) and portal vein injection of 99m Tc-macroaggregated albumin (MAA) in a group of eight dogs with chronic cirrhosis and acquired portosystemic shunts subsequent to total common bile duct ligation. Hepatic parenchymal damage was confirmed by alterations in liver function tests and liver histology. Seven of the eight dogs developed portal hypertension and had angiographic evidence of hepatofugal portal blood flow with multiple peripheral portosystemic anastomoses. Shunt fractions determined in the seven dogs with shunts varied from 39 to 100 using IMP and 45 to 93 using MAA. The remaining dog had normal portal pressure, a normal portal angiogram, and normal IMP and MAA scintigraphic studies. There was an excellent correlation between the two methods of shunt fraction calculation (R2 = 0.98) and the line of regression was not significantly different from unity (IMP = 1.09 × MAA - 0.03). 相似文献
105.
Earl F. Calfee III DVM Otto I. Lanz DVM Diplomate ACVS Daniel A. Degner DVM Diplomate ACVS Steven L. Peterson DVM MS MD Diplomate ACVS Robert B. Duncan DVM PhD Diplomate ACVP Richard V. Broadstone DVM PhD Diplomate ACVA Robert A. Martin DVM Diplomate ACVS ABVP Brenda Austin BS 《Veterinary surgery : VS》2002,31(1):32-43
OBJECTIVE: To assess donor-site morbidity and survival of the rectus abdominis muscle with an overlying skin graft after free tissue transfer to a medial femorotibial defect in dogs. STUDY DESIGN: Experimental study. SAMPLE POPULATION: Phase 1: 6 canine cadavers; phase 2: 7 adult mixed-breed dogs. METHODS: Phase 1: The rectus abdominis muscle was removed from canine cadavers, muscular and vascular dimensions were recorded, and angiography was performed. Phase 2: Muscular transfer was performed through anastomosis of the caudal epigastric artery and vein to the saphenous artery and medial saphenous vein. Transferred tissues were evaluated on postoperative days 3, 6, 10, and 13. Animals were examined daily until euthanasia between postoperative days 31 and 42. Postmortem angiograms were performed and tissues collected for histopathologic evaluation. RESULTS: Phase 1: Appropriate vascular dimensions for microvascular anastomosis were confirmed and surgical technique perfected. Phase 2: Muscular excision produced minimal donor-site morbidity. All muscles survived after microvascular transfer and angiography confirmed vascular patency. All of the skin grafts survived, with one graft undergoing partial necrosis. CONCLUSIONS: The rectus abdominis muscle can be successfully transferred to a medial femorotibial defect and can serve as a bed for acute skin grafting. No significant donor-site morbidity is associated with its removal. CLINICAL RELEVANCE: Microvascular free tissue transfer of the canine rectus abdominis muscle has not been previously described. This technique provides a new alternative for repair of appropriate wounds. Additional studies are needed to define its utility in clinical patients. 相似文献
106.
The aim of this work was to evaluate whether metalloporphyrin models could mimic the action of cytochrome P-450 in the oxidation of atrazine, a herbicide. The commercially available second-generation metalloporphyrins 5,10,15,20-tetrakis(2,6-dichlorophenyl)porphyrin metal(III) chloride [M(TDCPP)Cl] and 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin metal(III) chloride [M(TFPP)Cl] (metal = Fe or Mn) and the oxidants iodosylbenzene and metachloroperbenzoic acid were employed in this study. Results showed that the metalloporphyrins used here can oxidize atrazine. Yields as high as 32% were obtained for the Mn(TFPP)Cl/PhIO system, which shows that these catalysts can mimic both the in vivo and the in vitro action of cytochrome P-450, with formation of the metabolites DEA and DIA. The formation of five other unknown products was also detected, but only one of them could be identified, since the other four were present in very low concentrations. The compound COA, identified by mass spectrometry, was the main product in most of the oxidation reactions. 相似文献
107.
Alberto C. De Campos Bernardi Quirino A. De Camargo Carmello Sérgio Alves De Carvalho Eduardo Caruso Machado Camilo Lázaro Medina Mara De Menezes De Assis Gomes 《Journal of plant nutrition》2015,38(12):1902-1912
The objective of this research was to evaluate the nitrogen, phosphorus and potassium (NPK) fertilizer effect on the development of ‘Valencia’ sweet orange nursery trees budded on Rangpur lime rootstocks in a greenhouse using containers. The experiment was a complete (1/5) 53 factorial randomized blocks design. Treatments comprised five concentrations (g per plant) of N (1.25; 6.25; 11.25; 16.25; 21.25); K (0.42; 3.75; 6.22; 9.34; 12.45); and P (0.19; 0.89; 1.59; 2.29; 2.99). Carbon dioxide assimilation rate (A), transpiration rate (E), stomata conductance (gs), and internal carbon dioxide (CO2) concentration (Ci) and water use efficiency (WUE). Reducing sugar, sucrose and starch were evaluated. Response functions were adjusted and nutrient rates for maximum yield were presented. The results indicated that the high levels of N (>16.25 g per plant) interferes negatively on photosynthesis. Potassium at intermediate fertilization levels (from 3.75 to 6.22 g per plant) had positive effects on photosynthesis. But P had little interference on photosynthesis. Carbohydrates levels were not related to nutrients fertilized. 相似文献
108.
Adônis Moreira Larissa Alexandra Cardoso Moraes Isabelle Cristina Vilarino Lara Thiago Assis Rodrigues Nogueira 《Archives of Agronomy and Soil Science》2017,63(9):1281-1291
Soybean [Glycine max (L.) Merril] is the leading food crop worldwide, and selection of soybean genotypes for different levels of soil acidity may raise crop yield without the need to increase in planted area. An experiment in greenhouse conditions was conducted to determine the effects of two lime rates on soil chemical properties, grain yield (GY), yield components, nutritional status and physiological components of 15 soybean genotypes adapted to tropical and subtropical conditions. Genotypes BMX Apolo RR, BMX Potência RR, BRS 295RR, BRS 359RR, FPS Solar IPRO and TMG 716 IRR were the least responsive to soil acidity reduction, and BMX Turbo RR and BRS 360RR were the most responsive. Number of pods per pot, shoot dry weight yield, GY, photosynthesis, stomatal conductance, transpiration and chlorophyll increased significantly with increase in lime rate. Cultivar FPS Solar IPRO showed the highest foliar P, K, Ca and Mg concentrations in soybean, which was not observed in the grain, indicating the presence of genetic factors and the dilution effect on nutrient uptake. 相似文献
109.
MD. Rezaul Karim Di Tian Yue-Qiang Zhang Fan-Jun Chen 《Communications in Soil Science and Plant Analysis》2018,49(18):2345-2356
Suitable germplasm and breeding for zinc (Zn)-efficient genotypes has been prioritized to combat Zn deficiency problem. Six maize genotypes were grown in a nutrient solution with or without Zn to identify genotype tolerance to low Zn and its mechanism. Zhongnong 99 was found to be about 2-fold more Zn-efficient than L69 × 178. Young shoot Zn concentration and content was significantly correlated with Zn efficiency (ZE). Furthermore, Zn-efficient genotype as Zhongnong 99 distributed more Zn into young parts of shoot and also developed longer and thinner roots (≤ 0.2 mm) under -Zn conditions than inefficient genotypes. The close relationship (0.82***, 0.88***, 0.90***) between Zn content of young shoots and fine roots indicated that fine roots (≤ 0.2 mm) contributed more efficient Zn uptake into old parts which distributed to young parts. In conclusion, the analysis of young shoots and fine roots (≤ 0.2 mm) represent a suitable screening technique for ZE evaluation of under -Zn conditions. 相似文献
110.
Fábio Luiz Partelli Henrique Duarte Vieira Valério Bertolasse de Carvalho Francisco de Assis Alves Mourão Filho 《Journal of plant nutrition》2013,36(10):1651-1667
ABSTRACT The objective of this work was to establish and compare Diagnosis and Recommendation Integrated System (DRIS) norms with the sufficiency range approach, and apply these methods on nutritional diagnosis of Arabian coffee, in field samples collected in summer and winter in Southern Brazil. DRIS norms and sufficiency range were established in groves with average biennial yield equal or above 3000 kg ha? 1. The “t” test was used to verify the differences between the sufficiency range and the DRIS norms. The foliar concentrations of nitrogen (N), phosphorus (P), and sulfur (S) were higher in summer, and iron (Fe), and manganese (Mn) in winter. The reference values should be specific for the period of the year. There were differences in the foliar nutritional diagnosis, between the DRIS method and the sufficiency range approach. In samples during the summer analyzed with DRIS, copper (Cu), S, potassium (K), and zinc (Zn) were considered more limited nutrients and Mn, S, K, and calcium (Ca) when the sufficiency range was used. 相似文献