45 resultados para Hybrid particles
Resumo:
The eucalyptus offers several advantages compared to other forestry species and, by using the irrigation can increase productivity and decrease production time. The objective of the present study was to evaluate two hybrid eucalyptus (Grancam and Urograndis), no irrigation, dripping and micro sprinkler irrigated at 90, 120, 150 and 180 days after transplanting (DAT). The experiment was conducted at the experimental irrigation area in the State University of Mato Grosso do Sul, in the municipality of Aquidauna - State of MS, Brazil. The experimental design was randomized blocks, split plot with four blocks and two replications within each block, and the plots were composed by irrigation treatments (dripping, micro sprinkler irrigate and dry) and the subplots the hybrids (Grancam and Urograndis).The total area of the experiment had 3 hectares, where each plot consisted of 1 ha. It was evaluated plant height, stem diameter and canopy, stem basal area, the relationship between height and stem diameter, the relationship between height and canopy diameter and stem volume. Data were subjected to analysis of variance and compared by Tukey test at 5% probability. Irrigation systems and dripping sprinkle provide greater plant height, stem diameter, canopy diameter, stem basal area and stem volume.
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Objective To compare the diagnostic accuracy of the classic Meisels cytologic criteria and the Schneider secondary criteria relative to the hybrid capture method for diagnosing HPV infection. Methods This was a retrospective study performed at a public university hospital. A total of 41 patients with a cytologic diagnosis of HPV infection and 40 HPV-negative patients were selected for review of the cervical-vaginal smears seeking to classical and secondary criteria. A single pathologist reviewed the slides in search of the criteria. The classical and secondary cytologic criteria were compared with the hybrid capture for diagnosing HPV infection. Bartleti test was applied for the age analysis, and Fisher's exact test was used to compare proportions. The tests were considered significant when the probability of rejecting the null hypothesis was less than 5% (p < 0.05). Results The Meisels criteria were less sensitive (34.0%) than the secondary Schneider criteria (57.5%) when compared with the hybrid capture (p < 0.0001), although the specificity of the former criteria was non-significantly higher (91.2% and 67.7%, respectively). In cases of moderate or intense inflammation, the sensitivity and specificity of the Schneider criteria were decreased, 33.3% and 50.0% respectively (p = 0.0115). Conclusions Compared with hybrid capture for diagnosis of HPV infection, the sensitivity of the secondary Schneider criteria was higher than the classical Meisels criteria.Moderate or intense inflammation reduces the sensitivity and specificity of the secondary Schneider criteria for diagnosing HPV infection using the hybrid capture as the gold standard.
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Hybrids of Sorghum sudanensis (sudangrass) and Sorghum bicolor genotypes can produce high amounts of biomass, sorgoleone (a long chain hydroquinone), and other phytotoxic substances. Shoots and roots of a sorghum-sudangrass hybrid (cv. Trudan 8) were collected 10, 20, 30, 40, and 50 days after emergence. Four concentrations of aqueous extracts from the shoots and roots (0, 0.4, 2, and 10 g L-1, w/v) were used to treat seeds of lettuce (Lactuca sativa), tomato (Lycopersicum sculentum), purslane (Portulaca oleracea), and pigweed (Amaranthus retroflexus). Seed germination of lettuce, tomato, and pigweed was inhibited by extracts from sorghum-sudangrass shoots at 10 g L-1 when made from sorghum-sudangrass plants 20 days or less in age. Seed germination of purslane was not inhibited by any sorghum-sudangrass extract. Growth of the four species evaluated were systematically inhibited when treated with 10 g L-1 extracts from sorghum-sudangrass shoots harvested up to 10 days after emergence.
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The objective of this work was to evaluate the characteristics related to the photosynthetic ability of hybrid and inbred rice varieties, as a way to assess which of the two presented higher potential to stand out under conditions of competition. The trial was set in a greenhouse in completely randomized block design and 2 x 6 factorial scheme with four replications. Factor A consisted of rice varieties (hybrid or inbred) and factor B by competition levels. Treatments consisted in maintaining one plant of either BRS Pelota (inbred) or Inov (hybrid) variety at the center of the plot, under competition with 0, 1, 2, 3, 4 or 5 plants of the variety BRS Pelota at the periphery of the experimental unit, according to the treatment. Fifty days after emergence (DAE), sub-stomatal CO2 concentration (Ci - mmol mol-1), photosynthetic rate (A - mmol m-2 s-1) and CO2 consumed (DC - mmol mol-1) were quantified, as well as shoot dry mass(SDM).Hybrid plants present higher photosynthesis capacity than inbred plants, when competing with up to 3 times its own density. When under the same competitive intensity, hybrid plants surpass the inbred. However, it should be emphasized that, when in farm condition, the lower competitive capacity with weeds often attributed to the hybrid varieties, probably is due to their lower planting density, but if weed competition is kept at low levels, hybrid rice plants may perform in the same way or usually better than inbred plants.
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The effect of iron-ore particles on the propagule release and growth of Sargassum vulgare C. Agardh was tested under treatments with different concentrations of iron-ore particles: 0.1, 1.0, 10.0 g.L-1 and a solution of 10.0 g.L-1 of filtered iron-ore. Filtered seawater was used as control. Photosynthesis vs. irradiance (P-I) curves were calculated for S. vulgare in the presence of iron-ore and in seawater. There was no significant difference in the number of propagules released by the receptacles or in the percentage of zygote formation among the treatments. The released propagules acted like aggregation centers for the particles, those more heavily coated with iron (10.0 g.L-1) exhibiting the highest sinking velocity (32.6 ± 9.8 mm.s-1). No difference in the percentage of embryo survival was detected during the first week in culture. After four weeks the embryos grew in all treatments. Maximum frond development (5.3 ± 0.8 mm) was observed in treatment of seawater enriched with Provasoli's medium (PES) while initial filoids did not develop in three treatments without PES and with iron-ore (0.1 g.L-1, 1.0 g.L-1 and 10.0 g.L-1). The values for Pmax, alpha and respiration showed no significant differences between the P-I curves. The calculated value for I K was 106.26 µmol.m-2.s-1 to the control curve and 981.49 µmol.m-2.s-1 to the iron-ore curve. The results indicate that the iron-ore particles in high concentration reduce the growth of S. vulgare as they recovered the embryos, juveniles and young plants. In contrast, the presence of the particles did not affect the release of gametes, percentage of zygote formation or the percentage of embryo survival.
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RAPD-PCR molecular markers were used to identify common bean and soybean hybrid plants derived from crosses between closely related progenitors, with no apparent phenotypic differences. Primers OP-F12 and OP-0O3 were used to identify true hybrids derived from crosses between common bean cultivars Rudá (A 285) and AN 910408, and soybean cultivars Cristalina and Bossier, respectively. Each primer generated one polymorphic DNA band which was present in the male progenitor and absent in the female progenitor. As RAPD bands are normally inherited as dominant characters, the presence of these bands in the F1 plants confirmed their status.
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Genetic distances among cacao cultivars were calculated through multivariate analysis, using the D2 statistic, to examine racial group classification and to assess heterotic hybrids. A 5 x 5 complete diallel was evaluated. Over a five-year period (1986-1990), five cultivars of the S1 generation, pertaining to the Lower Amazon Forastero and Trinitario racial groups and 20 crosses between the corresponding S0 parents were analyzed, based upon five yield components - number of healthy and collected fruits per plant (NHFP and NCFP), wet seed weight per plant and per fruit (WSWP and WSWF), and percentage of diseased fruits per plant (PDFP). The diversity analysis suggested a close relationship between the Trinitario and Lower Amazon Forastero groups. A correlation coefficient (r) was calculated to determine the association between genetic diversity and heterosis. Genetic distance of parents by D2 was found to be linearly related to average performance of hybrids for WSWP and WSWF (r = 0.68, P < 0.05 and r = 0.76, P < 0.05, respectively). The heterotic performance for the same components was also correlated with D2, both with r = 0.66 (P < 0.05). A relationship between genetic divergence and combining ability effects was suggested because the most divergent cultivar exhibited a high general combining ability, generating the best performing hybrids. Results indicated that genetic diversity estimates can be useful in selecting parents for crosses and in assessing relationships among cacao racial groups.
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The uptake of lipids and lipoprotein particles by macrophages undergoes phagocytic activation and the formation of foam cells are key events in atherosclerosis. In this study we determined how intact high density lipoproteins (HDL) and apolipoproteins-HDL (removal of the lipid component from HDL, i.e., apoHDL) influence the phagocytosis of zymosan by mouse peritoneal macrophages. Zymosan particles preincubated together with lipoproteins or alone (control) were incubated with the macrophages. Phagocytosis activity was reported as the percent of macrophages that internalized three or more zymosan particles. HDL co-incubated with zymosan did not influence the over-all uptake of zymosan particles compared to apoHDL, which greatly enhanced the ability of the particle to be phagocytized (P<0.001). Part of this effect might be related to a greater binding of apoHDL to the particles compared to that of HDL (P<0.05). We conclude that this can be a useful method to study the ability of lipoproteins, including modified lipoproteins obtained from subjects with genetic forms of hyperlipidemia, to opsonize particles such as red blood cells and thus to investigate the processes that control the formation of foam cells and the mechanisms of atherogenesis.
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We developed an efficient method to prepare a hybrid inorganic-organic composite based on polyvinyl alcohol (PVA) and polysiloxane using the sol-gel disc technique. Antigen obtained from Yersinia pestis was covalently immobilized onto these discs with glutaraldehyde and used as solid phase in ELISA for antibody detection in serum of rabbits experimentally immunized with plague. Using 1.25 µg antigen per disc, a peroxidase conjugate dilution of 1:4,000 and a serum dilution of 1:200 were adequate for the establishment of the procedure. These values are similar to those used for PVA-glutaraldehyde discs, plasticized filter paper discs and the polyaniline-Dacron composite discs. This procedure is comparable to that which utilizes the adsorption of the antigen to conventional PVC plates, with the amount of antigen being one fourth that employed in conventional PVC plates (5 µg/well). In addition to the performance of the polysiloxane/PVA-glutaraldehyde disc as a matrix for immunodetection, its easy synthesis and low cost are additional advantages for commercial application.
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The molecular basis for RHD pseudogene or RHDpsi is a 37-bp insertion in exon 4 of RHD. This insertion, found in two-thirds of D-negative Africans, appears to introduce a stop codon at position 210. The hybrid RHD-CE-Ds, where the 3' end of exon 3 and exons 4 to 8 are derived from RHCE, is associated with the VS+V- phenotype, and leads to a D-negative phenotype in people of African origin. We determined whether Brazilian blood donors of heterogeneous ethnic origin had RHDpsi and RHD-CE-Ds. DNA from 206 blood donors were tested for RHDpsi by a multiplex PCR that detects RHD, RHDpsi and the C and c alleles of RHCE. The RHD genotype was determined by comparison of size of amplified products associated with the RHD gene in both intron 4 and exon 10/3'-UTR. VS was determined by amplification of exon 5 of RHCE, and sequencing of PCR products was used to analyze C733G (Leu245Val). Twenty-two (11%) of the 206 D-negative Brazilians studied had the RHDpsi, 5 (2%) had the RHD-CE-Ds hybrid gene associated with the VS+V- phenotype, and 179 (87%) entirely lacked RHD. As expected, RHD was deleted in all the 50 individuals of Caucasian descent. Among the 156 individuals of African descent, 22 (14%) had inactive RHD and 3% had the RHD-CE-Ds hybrid gene. These data confirm that the inclusion of two different multiplex PCR for RHD is essential to test the D-negative Brazilian population in order to avoid false-positive typing of polytransfused patients and fetuses.
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Electro-rotation can be used to determine the dielectric properties of cells, as well as to observe dynamic changes in both dielectric and morphological properties. Suspended biological cells and particles respond to alternating-field polarization by moving, deforming or rotating. While in linearly polarized alternating fields the particles are oriented along their axis of highest polarizability, in circularly polarized fields the axis of lowest polarizability aligns perpendicular to the plane of field rotation. Ellipsoidal models for cells are frequently applied, which include, beside sphere-shaped cells, also the limiting cases of rods and disks. Human erythrocyte cells, due to their particular shape, hardly resemble an ellipsoid. The additional effect of rouleaux formation with different numbers of aggregations suggests a model of circular cylinders of variable length. In the present study, the induced dipole moment of short cylinders was calculated and applied to rouleaux of human erythrocytes, which move freely in a suspending conductive medium under the effect of a rotating external field. Electro-rotation torque spectra are calculated for such aggregations of different length. Both the maximum rotation speeds and the peak frequencies of the torque are found to depend clearly on the size of the rouleaux. While the rotation speed grows with rouleaux length, the field frequency nup is lowest for the largest cell aggregations where the torque shows a maximum.
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We determined the influence of fasting (FAST) and feeding (FED) on cholesteryl ester (CE) flow between high-density lipoproteins (HDL) and plasma apoB-lipoprotein and triacylglycerol (TG)-rich emulsions (EM) prepared with TG-fatty acids (FAs). TG-FAs of varying chain lengths and degrees of unsaturation were tested in the presence of a plasma fraction at d > 1.21 g/mL as the source of CE transfer protein. The transfer of CE from HDL to FED was greater than to FAST TG-rich acceptor lipoproteins, 18% and 14%, respectively. However, percent CE transfer from HDL to apoB-containing lipoproteins was similar for FED and FAST HDL. The CE transfer from HDL to EM depended on the EM TG-FA chain length. Furthermore, the chain length of the monounsaturated TG-containing EM showed a significant positive correlation of the CE transfer from HDL to EM (r = 0.81, P < 0.0001) and a negative correlation from EM to HDL (r = -041, P = 0.0088). Regarding the degree of EM TG-FAs unsaturation, among EMs containing C18, the CE transfer was lower from HDL to C18:2 compared to C18:1 and C18:3, 17.7%, 20.7%, and 20%, respectively. However, the CE transfer from EMs to HDL was higher to C18:2 than to C18:1 and C18:3, 83.7%, 51.2%, and 46.3%, respectively. Thus, the EM FA composition was found to be the rate-limiting factor regulating the transfer of CE from HDL. Consequently, the net transfer of CE between HDL and TG-rich particles depends on the specific arrangement of the TG acyl chains in the lipoprotein particle core.
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A previous study showed that BMP-2 (bone morphogenetic protein-2) and wear debris can separately support osteoclast formation induced by the receptor activator of NF-κB ligand (RANKL). However, the effect of BMP-2 on wear debris-induced osteoclast formation is unclear. In this study, we show that neither titanium particles nor BMP-2 can induce osteoclast formation in RAW 264.7 mouse leukemic monocyte macrophage cells but that BMP-2 synergizes with titanium particles to enhance osteoclast formation in the presence of RANKL, and that at a low concentration, BMP-2 has an optimal effect to stimulate the size and number of multinuclear osteoclasts, expression of osteoclast genes, and resorption area. Our data also clarify that the effects caused by the increase in BMP-2 on phosphorylated SMAD levels such as c-Fos expression increased throughout the early stages of osteoclastogenesis. BMP-2 and titanium particles stimulate the expression of p-JNK, p-P38, p-IkB, and P50 compared with the titanium group. These data suggested that BMP-2 may be a crucial factor in titanium particle-mediated osteoclast formation.
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This work presents the results of a Hybrid Neural Network (HNN) technique as applied to modeling SCFE curves obtained from two Brazilian vegetable matrices. A series Hybrid Neural Network was employed to estimate the parameters of the phenomenological model. A small set of SCFE data of each vegetable was used to generate an extended data set, sufficient to train the network. Afterwards, other sets of experimental data, not used in the network training, were used to validate the present approach. The series HNN correlates well the experimental data and it is shown that the predictions accomplished with this technique may be promising for SCFE purposes.
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One of the main features that confer high quality to the seed is its genetic purity, in which one of the major causes of contamination is the self-pollination of the female parent. Up to date, there is no accurate and fast methods for detecting such contamination. Thus, this work was carried out to certify the genetic purity in seeds of hybrid maize using different biochemical and DNA-based markers. Two single-cross hybrids and their parental lines derived from the maize breeding program at UFLA were evaluated by isoenzymatic pattern of alcohol dehydrogenase (ADH), esterase (EST), acid phosphatase (ACP), glutamate-oxaloacetate transaminase (GOT), malate dehydrogenase (MDH), isocitrate dehydrogenase (IDH), phosphoglucomutase (PGM), 6-phosphoglucomate dehydrogenase (PGDH), catalase (CAT) and ß-glucosidade (ßGLU) and by microsatellites markers. The enzymatic systems that were able to distinguish the hybrids from their parental line were the catalase, the isocitrate dehydrogenase and the esterase. The esterase showed a Mendelian segregation pattern for UFLA 8/3 hybrid, that enables a safer genetic purity certificate. Microsatellites were able to differentiate the hybrid lines and the respective parental lines. Moreover, this technique was fast, precise and without environment effects. For microsatellites, the amplification pattern was identical when young leaves or seeds were used as DNA source. The possibility of using seeds as DNA source would accelerate and facilitate the role process of the genetic purity analysis.