996 resultados para Flores - Maturação


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We report measurements of single- and double-spin asymmetries for W^{±} and Z/γ^{*} boson production in longitudinally polarized p+p collisions at sqrt[s]=510  GeV by the STAR experiment at RHIC. The asymmetries for W^{±} were measured as a function of the decay lepton pseudorapidity, which provides a theoretically clean probe of the proton's polarized quark distributions at the scale of the W mass. The results are compared to theoretical predictions, constrained by polarized deep inelastic scattering measurements, and show a preference for a sizable, positive up antiquark polarization in the range 0.05

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We report the first measurements of the moments--mean (M), variance (σ(2)), skewness (S), and kurtosis (κ)--of the net-charge multiplicity distributions at midrapidity in Au+Au collisions at seven energies, ranging from sqrt[sNN]=7.7 to 200 GeV, as a part of the Beam Energy Scan program at RHIC. The moments are related to the thermodynamic susceptibilities of net charge, and are sensitive to the location of the QCD critical point. We compare the products of the moments, σ(2)/M, Sσ, and κσ(2), with the expectations from Poisson and negative binomial distributions (NBDs). The Sσ values deviate from the Poisson baseline and are close to the NBD baseline, while the κσ(2) values tend to lie between the two. Within the present uncertainties, our data do not show nonmonotonic behavior as a function of collision energy. These measurements provide a valuable tool to extract the freeze-out parameters in heavy-ion collisions by comparing with theoretical models.

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We report the first measurement of charmed-hadron (D(0)) production via the hadronic decay channel (D(0) → K(-) + π(+)) in Au+Au collisions at sqrt[s(NN)] = 200 GeV with the STAR experiment. The charm production cross section per nucleon-nucleon collision at midrapidity scales with the number of binary collisions, N(bin), from p+p to central Au+Au collisions. The D(0) meson yields in central Au + Au collisions are strongly suppressed compared to those in p+p scaled by N(bin), for transverse momenta p(T) > 3 GeV/c, demonstrating significant energy loss of charm quarks in the hot and dense medium. An enhancement at intermediate p(T) is also observed. Model calculations including strong charm-medium interactions and coalescence hadronization describe our measurements.

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We present ΛΛ correlation measurements in heavy-ion collisions for Au+Au collisions at sqrt[s_{NN}]=200  GeV using the STAR experiment at the Relativistic Heavy-Ion Collider. The Lednický-Lyuboshitz analytical model has been used to fit the data to obtain a source size, a scattering length and an effective range. Implications of the measurement of the ΛΛ correlation function and interaction parameters for dihyperon searches are discussed.

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The Structural Genomics Consortium (SGC) and its clinical, industry and disease-foundation partners are launching open-source preclinical translational medicine studies.

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Lateral pterygoid muscle (LPM) plays an important role in jaw movement and has been implicated in Temporomandibular disorders (TMDs). Migraine has been described as a common symptom in patients with TMDs and may be related to muscle hyperactivity. This study aimed to compare LPM volume in individuals with and without migraine, using segmentation of the LPM in magnetic resonance (MR) imaging of the TMJ. Twenty patients with migraine and 20 volunteers without migraine underwent a clinical examination of the TMJ, according to the Research Diagnostic Criteria for TMDs. MR imaging was performed and the LPM was segmented using the ITK-SNAP 1.4.1 software, which calculates the volume of each segmented structure in voxels per cubic millimeter. The chi-squared test and the Fisher's exact test were used to relate the TMD variables obtained from the MR images and clinical examinations to the presence of migraine. Logistic binary regression was used to determine the importance of each factor for predicting the presence of a migraine headache. Patients with TMDs and migraine tended to have hypertrophy of the LPM (58.7%). In addition, abnormal mandibular movements (61.2%) and disc displacement (70.0%) were found to be the most common signs in patients with TMDs and migraine. In patients with TMDs and simultaneous migraine, the LPM tends to be hypertrophic. LPM segmentation on MR imaging may be an alternative method to study this muscle in such patients because the hypertrophic LPM is not always palpable.

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The Orchidaceae is one of the largest flowering plants family and with a great importance to conservation. However, no survey on orchid flowers can be found in Mato Grosso do Sul. Thus, the objective of this work was to make a survey of the Orchidaceae species and of its ecology features in a riparian forest in a fragment of Floresta Estacional Semi-Decidual that belongs to the riparian forest of the Dourados River. The inventory was made by using a sweeping method for collection, and in addition to this the vertical and horizontal position of epiphytes were assessed on the hosts. For characterization of microclimate, it was used a thermohygrometer and luximeter. It was identified 17 species of 13 genera. Of the listed genera, the most abundant ones were: Acianthera, Macradenia and Capanemia. It was also noted a vertical and horizontal distribution of the Orchidaceae in relation to inverse gradient of water and light availability. Some species tended to be sensitive to height level categorization, whereas others seemed to occur with similar frequency along the host. In relation to the cardinal orientation, the apparent preferential response for south and east directions was associated to the low sampling effort and lower water availability, which could occur because the north face is opposed to the water body.

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Annatto seeds do not germinate during early stages of their development because of insufficient reserve substances. In situ analysis showed that the principal reserves are proteins and starch, deposited in endosperm cells. During the early stages of development, the starch grains were elliptic, because amylose was the minor component. During development, these grains became more spherical due to an increase in amylose relative to amylopectin. Endosperm cells do not contain protein bodies, but they accumulate proteins dispersed in the cytoplasm. At the final stage of development the proteins became compacted due to the dehydration of the seeds wich is part of the global process of orthodox seeds maturation. Natural fluorescence revealed aromatic amino acids, principally tryptophan and tyrosine in the proteins. The seeds reached their maximum dry weight after moisture contents had declined to around 60%. At this point the seeds presented maximum germination capacity.

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Annona dioica St. Hil. is a species that grows to approximately 2 m tall and is very widespread in the cerrados. Individual plants of this androdioecious species produce numerous hermaphroditic or male flowers, but few fruits. The aim of this study was to determine the sex ratio among the plants and to compare the frequency of herbivory between male and hermaphroditic flowers. The fieldwork was done by studying flowering plants in grasslands used as pasture for cattle at Fazenda Nhumirim. One hundred and forty-seven male plants and 71 hermaphroditic plants were examined and produced a total of 194 and 94 flowers, respectively, during the study period. The male:hermaphrodite sex ratio was 2.07:1, and was similar to the male:hermaphrodite flower ratio of 2.06:1. The frequency of florivory rate in hermaphrodites was significantly higher than in male flowers (33.0%, n = 31, and 25.7%, n = 50, respectively; G = 14.83; d.f. = 1; p < 0.001). The mean fresh weights of male and hermaphroditic flowers were significantly different (8.38 ± 2.40 g vs. 6.93 ± 2.68 g, respectively; 0 ± SEM; n = 50 each; t = 2.479; d.f. = 49; p = 0.017). These results indicate that the low fruit set in this species can be explained by the sex ratio, the greater herbivory of hermaphroditic flowers and the probable absence of pollinators.

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A study of the tree species of the order Celastrales sensu Cronquist from the Tibagi river basin, Paraná state, Brazil, is presented, based on herbarium material. This basin is subdivided into three zones, from north to south: lower Tibagi (BT), mid Tibagi (MT) and upper Tibagi (AT), each with different environmental conditions and vegetation types. The order Celastrales is represented in the basin by 15 tree species belonging to three families: Aquifoliaceae, Celastraceae and Icacinaceae. Icacinaceae has only two species, Citronella gongonha and C. paniculata. The former is distinguished by a glabrous ovary and leaves that usually bear thorns. Aquifoliaceae has six species: Ilex brasiliensis, I. brevicuspis, I. chamaedryfolia, I. dumosa, I. paraguariensis and I. theezans. These species are found mainly in AT and MT and are distinguished by leaf size, indument, apices and margins, and by sepal features. Celastrales is represented by seven species and two genera; Plenckia populnea, a Brazilian savannah species found only in MT, and six species of Maytenus (M. evonymoides, M. robusta, M. dasyclada, M. salicifolia, M. ilicifolia and M. aquifolia) distinguished by leaf size and margins, branch shape and number of flowers per inflorescence.

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The aim of this work was to describe the morphology and ontogeny of P. riedelii fruits to aid in taxonomic, ecological and phylogenetic studies in Apocynaceae. Fruits were fixed in FAA, embedded in plastic resin, sectioned at 10 ìm and stained with toluidine blue, for structural analysis. The fruit of P. riedelii is a follicarium, with two follicular fruitlets. The epicarp is one-cell-layered, with trichomes and thick cuticle. The mesocarp, originating from fundamental ovary tissue, is parenchymatous with laticifers, non-lignified fibers and vascular bundles. The endocarp sensu lato is two-celllayered of crossed sclereids, originating from the inner ovary epidermis and from a single layer of parenchyma cells of fundamental ovary tissue. Follicle dehiscence is lateral and the dehiscence process involves anatomical characteristics such as a dehiscence zone with thin-walled cells, non-lignified fibers in the mesocarp and crossed sclereids in the endocarp.

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This revision of Leptolobium Vogel includes an identification key, descriptions, illustrations, and distribution maps for the taxa. Leptolobium comprises 12 species, and is characterized by its arboreal or shrubby habit, flowers with white, actinomorphic or slightly zygomorphic corollas, 10 free stamens, a stipitate ovary with many ovules, indehiscent (samara-like or nut-like) fruits, compressed seeds, and a bulbose hypocotyl-radicle axis. Leptolobium is a neotropical genus that occurs from Mexico to northern Argentina. Eleven species are found in Brazil, seven of which are endemic to the country. The lectotype of Sweetia glazioviana Harms is designated in this paper. In addition, information about uses, common names, geographical distribution, and habitats are provided.

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The durability and postharvest quality of cut flowers are fundamental attributes in value along the production chain and in consumer satisfaction. The objective of this study was to evaluate the effect of chemical inhibitors of ethylene action on maintaining the postharvest quality of chrysanthemum stems (Chrysanthemum morifolium Ramat cv. Dragon). The experiment tested maintenance solutions with silver thiosulfate (STS) under five levels (distilled water, a 0.2 mM STS, the STS 0.2 mM + sucrose at 50 g L-1, STS at 0.4 mM; STS at 0.4 mM + sucrose at 50 g L-1), and date of sampling, for three levels (0, 3, 6 days). Three replications with two flower stems in each treatment were used in the experiment. Physical assessments were made: color, fresh mass and relative water content; chemical evaluations: reducing sugars and pigments, and qualitative assessments: turgidity, flower color, and number of buds, open flowers and partially open flowers. Treatment with 0.2 mM STS resulted in better maintenance of fresh mass of stems. The concentration of pigments and reducing sugar was higher in those treatments in which sucrose was associated. The color and relative water content were favored in treatments STS 0.2 mM and 0.4 mM. The concentration of 0.2 mM STS obtained the best results, prolonging the vase life the stems. The quality of these stems was higher, with the best assessments of water content, color and turgidity.

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The development and use of techniques that extend the life vase of the flowers, maintaining the quality of the product, is essential for reducing postharvest losses. The objective of this work was to evaluate different solutions for maintenance, associated or not to sucrose, in maintaining the postharvest quality of chrysanthemum stems. The treatments used distilled water, 8-HQC to 100 mg L-1, 8-HQC to 100 mg L-1 + sucrose 50 g L-1, 8-HQC to 200 mg L-1, 8-HQC to 200 mg L-1 + sucrose 50 g L-1. Physical assessments were made: color, fresh mass and relative water content; chemical evaluations: reducing sugars and pigments, and qualitative assessments: turgidity, color of the flowers, and number of buttons, open flowers and partially open flowers. The combination of 8-HQC 200 mg L-1 + sucrose 50 g L-1 was the best performance that made for maintaining the quality of flower stems, favoring the opening of buttons and turgidity of petals. Sucrose contributed to better maintenance of the reserve substances in the shaft, which had increased the flower vase life.

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PURPOSE: To determine the main causes of penetrating keratoplasty indications at Hospital das Clínicas-UNICAMP (January, 1999 to December, 2003). METHODS: A non-comparative, retrospective series of case studies. The authors reviewed the files of 857 patients who underwent penetrating keratoplasty at Hospital das Clínicas-UNICAMP between 1999-2003 and classified them into different categories according to diagnostic indication for surgery. RESULTS: The age range was between 0-88 years (average 44 years ±1.2). The main causes of penetrating keratoplasty were: keratoconus in 427 cases (49.82%); 152 cases (17.74%) of corneal ulceration (perforated or not); corneal graft failure in 87 cases (10.15%); bullous keratopathy, 72 cases (8.40%); Fuchs dystrophy in 59 cases (6.88%); trachoma complications in 28 cases (3.27%); other causes, 32 (3.74%). In children under 10 years of age, the main cause of penetrating keratoplasty indications was infectious ulcer (77.78%) and between 11-50 years of age, keratoconus was the main cause (71.65%). CONCLUSION: This study was composed of a young population, and the main causes of penetrating keratoplasty were keratoconus and therapeutic keratoplasty.