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101.
Rafael da S. Messias Carlos A. P. Silveira Vanessa Galli Clenio N. Pillon César V. Rombaldi 《Journal of plant nutrition》2015,38(6):959-972
Pyrolysis of pyrobituminous shale rock to extract products such as fuel oil and gas generate a liquid by-product called shale water (SW). In this study, the physical-chemical characterization of SW was performed and the effects on plant growth, mineral nutrition, and food safety were evaluated when applied via foliar in lettuce crop. Shale water showed a great diversity of organic compounds, minerals, and trace elements. The application of SW in lettuce resulted in no phytotoxic effect or accumulation of toxic elements to human health within the doses tested, and increased yield and the accumulation of several mineral nutrients in the leaves. The absorption and accumulation of zinc, copper, cobalt, molybdenum, and manganese was also improved when these minerals were applied together with SW. These results suggest that SW plays a role as a biostimulant and could be used in agriculture as a safety alternative to increase yield and biofortify crops. 相似文献
102.
Gabriel Ribas Pereira Fernanda Silveira Flores Vogel Rodrigo Camponogara Bohrer Janduí Escarião da Nóbrega Gustavo Freitas Ilha Paulo Roberto Antunes da Rosa Werner Giehl Glanzner Giovana Camillo Patricia Braunig João Francisco Coelho de Oliveira Paulo Bayard Dias Gonçalves 《Veterinary parasitology》2014,199(3-4):129-135
Neosporosis has been considered the main cause of abortion between the first and the second trimester of pregnancy in cattle. Therefore, the objective of this study was to identify the presence of Neospora caninum DNA obtained from experimental models based on the evaluation of different areas of the fetal nervous system and organs from heifers previously inoculated with NC-1 after or before insemination. This study was performed with Hereford × Nelore (n = 29) heifers and all animals were considered free of diseases at the beginning of the experiment. All animals were bred by fixed-time artificial insemination (TAI) and allocated as follows: (a) seronegative heifers subjected to TAI (TAI, n = 9), (b) heifers infected with N. caninun 60 days prior to TAI (NC-1 + TAI, n = 9), and (c) heifers submitted to TAI and infected with N. caninum 60 days later (TAI + NC-1, n = 11). The pregnancy was confirmed by transrectal ultrasonography 35 days after TAI and evaluated every 30 days until the end of gestation. Fetuses were collected surgically at 170 days of gestation, and immediately necropsied to remove tissues aseptically. Samples of the central nervous system (CNS), heart, kidney, lung, liver, skeletal muscle and caruncle were collected for DNA extraction. Days of gestation at abortion and interval from abortion to first insemination were examined by Student's t-test. At 35 days of gestation the pregnancy rates in the group NC-1 + TAI (4/9, 44.4%) was lower than in the control group (8/9, 88.8%, P < 0.05). At 60 days, the pregnancy rates in the NC-1 + TAI group (0/4, 0%) was lower compared to TAI + NC-1 (5/7, 71.4%) and control (6/8, 75.0%) groups (P < 0.05). Animals from the group NC-1 + TAI were re-inseminated 60 days after the first TAI. After pregnancy losses throughout the study, 5 animals (TAI), 3 animals (NC-1 + TAI) and 5 animals (TAI + NC-1) maintained pregnancy until 170 days of gestation. TaqMan RT-PCR demonstrated the presence of N. caninum DNA in the medulla and right posterior cortex in 3 out of 5 fetuses from the TAI + NC-1 group. We concluded that heifers infected after TAI had a higher incidence of the parasite at the fetus CNS. Identification of N. caninum by TaqMan RT-PCR would assist in the investigation of infection and in the evaluation of vaccines or therapeutic drugs to control neosporosis in cattle. 相似文献
103.
Pena A Pelantova N Lino CM Silveira MI Solich P 《Journal of agricultural and food chemistry》2005,53(10):3784-3788
An analytical method for the determination of OTC and TC residues in honey was developed. Sample treatment involves an extraction in EDTA-McIlvaine buffer, followed by a solid-phase cleanup step. With regard to the cleanup procedure, different SPE cartridges were evaluated and the results presented. The method was validated according to the guidelines laid down by the 2002/657/EC European Decision parameters: decision limit (Cc alpha) and detection capability (CC beta) were 20 and 21 microg/Kg and 49 and 50 microg/Kg for OTC and TC, respectively, and recoveries of OTC and TC from spiked samples, at three fortification levels, were higher than 87% for both compounds. The analytical method was applied to 57 honey samples. 相似文献
104.
Daniel Bernardi Marcos Botton Uemerson Silva da Cunha Oderlei Bernardi Thibaut Malausa Mauro Silveira Garcia Dori Edson Nava 《Pest management science》2013,69(1):75-80
BACKGROUND: The spider mite, Tetranychus urticae, is the major strawberry pest in Brazil. The main strategies for its control comprise synthetic acaricides and predatory mites. The recent register of a commercial formula of azadirachtin (Azamax® 12 g L?1) can be viable for control of T. urticae. In this work, the effects of azadirachtin on T. urticae and its compatibility with predatory mites Neoseiulus californicus and Phytoseiulus macropilis in the strawberry crop were evaluated. RESULTS: Azadirachtin was efficient against T. urticae, with a mortality rate similar to that of abamectin. In addition, the azadirachtin showed lower biological persistence (7 days) than abamectin (21 days). Azadirachtin did not cause significant mortality of adult predatory mites (N. californicus and P. macropilis), but it did reduce fecundity by 50%. However, egg viability of the azadirachtin treatments was similar to that of the control (>80% viability). The use of azadirachtin and predatory mites is a valuable tool for controlling T. urticae in strawberry crop. CONCLUSIONS: Azadirachtin provided effective control of T. urticae and is compatible with the predatory mites N. californicus and P. macropilis. It is an excellent tool to be incorporated into integrated pest management for strawberry crop in Brazil. Copyright © 2012 Society of Chemical Industry 相似文献
105.
Intraerythrocytic protozoan species of the genera Theileria and Babesia are known to infect both wild and domestic animals, and both are transmitted by hard-ticks of the family Ixodidae. The prevalences of hemoprotozoa and ectoparasites in 15 free-living Mazama gouazoubira, two captive M. gouazoubira and four captive Blastocerus dichotomus from the State of Minas Gerais, Brazil, have been determined through the examination of blood smears and the use of nested polymerase chain reaction (nPCR). The cervid population was inspected for the presence of ticks and any specimens encountered were identified alive under the stereomicroscope. Blood samples were collected from all 21 animals, following which blood smears were prepared, subjected to quick Romanowsky staining and examined under the optical microscope. DNA was extracted with the aid of commercial kits from cervid blood samples and from tick salivary glands. The nPCR assay comprised two amplification reactions: the first was conducted using primers specific for a 1700 bp segment of the 18S rRNA gene of Babesia and Theileria species, whilst the second employed primers designed to amplify a common 420 bp Babesia 18S rRNA fragment identified by aligning sequences from Babesia spp. available at GenBank. The ticks Amblyomma cajennense, Rhipicephalus microplus and Dermacentor nitens were identified in various of the cervids examined. Of the animals investigated, 71.4% (15/21) were infected with hemoprotozoa, including Theileria cervi (47.6%), Theileria sp. (14.3%), Babesia bovis (4.8%) and Babesia bigemina (4.8%). However, only one of the infected wild cervids exhibited accentuated anaemia (PCV=17%). This is first report concerning the occurrence of Theileria spp. in Brazilian cervids. 相似文献
106.
When a bubble of air rises to the top of a highly viscous liquid, it forms a dome-shaped protuberance on the free surface. Unlike a soap bubble, it bursts so slowly as to collapse under its own weight simultaneously, and folds into a wavy structure. This rippling effect occurs for both elastic and viscous sheets, and a theory for its onset is formulated. The growth of the corrugation is governed by the competition between gravitational and bending (shearing) forces and is exhibited for a range of densities, stiffnesses (viscosities), and sizes-a result that arises less from dynamics than from geometry, suggesting a wide validity. A quantitative expression for the number of ripples is presented, together with experimental results that support the theoretical predictions. 相似文献
107.
Raico E Laria Lamela Raquel Silveira Coffigny Yanis Cruz Quintana Mercedes Martínez 《Aquaculture Research》2005,36(13):1293-1297
Phenoloxidase and peroxidase activity were analysed in haemolymph of juvenile shrimp, Litopenaeus schmitti, exposed to different salinity levels (35%, 18%, 8%) for 48 h. A significant reduction (P<0.05) in total glucose and phenoloxidase activity in animals exposed to lower salinities (18% and 8%) was recorded, while peroxidase activity and total protein concentration did not vary. Histology revealed the occurrence of oedema in gills in shrimp exposed to 8%. The work demonstrates for the first time that in L. schmitti, low salinities can decrease glucose levels in haemolymph and create an immunosuppressive state by reducing phenoloxidase activity. 相似文献
108.
Camila Tangari Meira MD Rogério Abdallah Curi Josineudson Augusto II Vasconcelos Silva Marcio José Monteiro CorrêaMarcilio Dias Silveira da Mota PhD 《Journal of Equine Veterinary Science》2013
To investigate morphological and genomic differences between cutting and racing lines of Quarter Horses, 120 racing and 68 cutting animals of both sexes, registered at the Brazilian Association of Quarter Horse Breeders, were used. Blood samples were collected, and the following physical traits were measured: weight; height at withers; body length; length of the shank, pastern, rump, head, and neck; and chest, shank, and hoof circumference. For analysis of genomic differences, 54,602 single-nucleotide polymorphisms (SNPs) were genotyped using the Equine SNP50 BeadChip, and the quality of individual and SNP genotype data were evaluated. The fixation index, FST, was used to identify genome regions that were altered in the lines by selection. The results showed significant differences between the lines in all physical traits. Quality control led to the exclusion of four cutting animals with a call rate of <0.95. After filtering, 12,544, 13,815, and 13,370 SNPs were excluded for the whole population (n = 184), the 120 racing animals, and the 64 cutting animals, respectively. The number of informative polymorphisms detected in each line and in the whole population indicated that the Equine SNP50 BeadChip can be used in genetic studies of Quarter Horses. The fixation index, FST, identified 2,558 genome regions that may have been modified by divergent selection. 相似文献
109.
Deciduous trees with high-density wood that occur in dry seasonal tropical regions respond to rainfall seasonality with synchrony in phenophases. However, they may exhibit interannual differences in sy... 相似文献
110.
Argenta JS Alves SH Silveira F Maboni G Zanette RA Cavalheiro AS Pereira PL Pereira DI Sallis ES Pötter L Santurio JM Ferreiro L 《Veterinary microbiology》2012,157(1-2):137-142
The present study investigated the in vitro inhibitory activity of terbinafine, itraconazole, caspofungin, fluvastatin and ibuprofen against 15 isolates of Pythium insidiosum in double and triple combinations and determined in vivo correlations using rabbits with experimental pythiosis. The minimal inhibitory concentration (MIC) was determined in accordance with the Clinical and Laboratory Standards Institute M 38-A2 protocol (2008), and the in vitro interactions were evaluated using a checkerboard microdilution method. For the in vivo study, 20 rabbits inoculated with P. insidiosum zoospores were divided into four groups: group 1 was treated with terbinafine and itraconazole; group 2 was treated with terbinafine, itraconazole and fluvastatin; group 3 was treated with terbinafine and caspofungin; and group 4 was the control group. Combinations of terbinafine with caspofungin or ibuprofen were synergistic for 47% of the isolates, and antagonism was not observed in any of the double combinations. The triple combinations were mostly indifferent, but synergism and antagonism were also observed. In the in vivo study, the histological aspect of the lesions was similar among the groups, but group 2 showed the lowest amount of hyphae and differed significantly from the other groups. 相似文献