998 resultados para Rosas, Sergio Eduardo
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The present paper describes the one-pot procedure for the formation of self-assembled thin films of two silanes on the model oxidized silicon wafer, SiO2/Si. SiO2/Si is a model system for other surfaces, such as glass, quartz, aerosol, and silica gel. MALDI-TOF MS with and without a matrix, XPS, and AFM have confirmed the formation of self-assembled thin films of both 3-imidazolylpropyltrimethoxysilane (3-IPTS) and 4-(N- propyltriethoxysilane-imino)pyridine (4-PTSIP) on the SiO2/Si surface after 30 min. Longer adsorption times lead to the deposition of nonreacted 3-IPTS precursors and the formation of agglomerates on the 3-IPTS monolayer. The formation of 4-PTSIP self-assembled layers on SiO2/Si is also demonstrated. The present results for the flat SiO2/Si surface can lead to a better understanding of the formation of a stationary phase for affinity chromatography as well as transition-metal-supported catalysts on silica and their relationship with surface roughness and ordering. The 3-IPTS and 4-PTSIP modified SiO2/Si wafers can also be envisaged as possible built-on-silicon thin-layer chromatography (TLC) extraction devices for metal determination or N-heterocycle analytes, such as histidine and histamine, with on-spot MALDI-TOF MS detection. © 2005 Elsevier Inc. All rights reserved.
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In this article we rewiewed the indications of the low-dose hormone replacement therapy in post menopausal women. We evaluate the effects of this therapy on menopausal symptoms bone metabolism, cardiovascular risk and endometrial cancer. The low-dose hormone replacement therapy is satisfactory to relief menopausal symptoms and improves lipid profile preventing atherosclerosis. It does not increase the risk of hyperplasia or endometrial cancer when is associate with progestagens. The low dose hormone replacement therapy is also associate to improve bone mineral density but to have better comprehension about the effective action of the low dose hormone replacement therapy on bone, more studies evaluating the risk of fractures are necessary.
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To know the origin of the ischiatic nerve in mocos (Kerodon rupestris Wied,1820) near by intervertebral forames and the muscling belonging to its routes were used 10 adult animals, from CEMAS-ESAM. After natural obit, they were fixed in formol (10%) and dissected to exposition and to singt of the ischiatic nerve. The results were indicated in percentage. Variations in the quantity of the lumber and sacral vertebras nere observed, five animals (50,00%) reveled seven lumbar vertebras and three sacral ones; two animals recrealed seven lumbar vertebras and four sacral ones, and two animals reveled six lumbar vertebras and three sacral ones. An animal (10,00%) revealed six lumbar vertebras and four ones. Therefore, the origin of the nerve was differentiated five animals (50,00%) had the participation of L 7,S 1,S 2; two animals (20,00%) with L 7,S 1; and a little part of S 2. Two animals (20,00%) with L 6,S 1,S 2, and an animal (10,00%) with L 6,S 1, and a little part of S 2. The last root of the ischiatic nerve in all its origins, contribute to the constitution of the first root of pudental nerve. It was verified that in all its route, the ischiatic nerves (100,00%) ceded branches to the muscles: medial gluteus, deep gluteus, superficial gluteus, emiting muscular branches to the femoral biceps or to thigh, and to the semimembranous and semi-tendinous muscles, that is continuous with a high calibre trunk, originating the fibular nerve(sideways), the tibial nerve(medial) and the lateral plantar sural cutaneous nerve (caudal).
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Brazil has an important role in the biomass burning aerosol activity. During the Dry Season (June-September) of 2009 an aerosol profiling campaign was carried out using a backscattering and Raman lidar system in Rio Claro-SP, Brazil (22°23'S and 47°32'W). The main goal of this campaign was to observe the biomass burning aerosol load due to sugarcane crops and also study the air dispersion conditions, planetary boundary and mixed layer daily evolution. In this paper we aim to present the preliminary results of the influence of this type of aerosol over the city of Rio Claro-SP, Brazil and one case study to evaluate the aerosol profile in a biomass burning episode that occurred in July, 2009. On July 15 an intense burning was observed about 300 m away from the lidar location. Throughout the measurements it was observed that the plumes reached up to 900 m, and that there was a time gap between the plumes. The gas analyzers showed a strong influence of this burning as it was noticed in the measurements of CO, NO x and nephelometer, whereas the PM10 did not have due to this burning, possibly because the particulate was deposited further from the emission source, not being detected by the equipment. © Sociedad Española de Óptica.
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Incluye Bibliografía
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The invasive fire ant Solenopsis invicta is medically important because its venom is highly potent. However, almost nothing is known about fire ant venom proteins because obtaining even milligram-amounts of these proteins has been prohibitively challenging. We present a simple and fast method of obtaining whole venom compounds from large quantities of fire ants. For this, we separate the ants are from the nest soil, immerse them in dual-phase mixture of apolar organic solvent and water, and evaporate each solvent phase in separate. The remaining extract from the aqueous phase is largely made up of ant venom proteins. We confirmed this by using 2D gel electrophoresis while also demonstrating that our new approach yields the same proteins obtained by other authors using less efficient traditional methods. © 2013 Elsevier Ltd.
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In this study, we aimed to determine the prevalence and risk factors associated to Toxoplasma gondii infection in sheep from northeastern Brazil. A total of 932 ovine serum samples from 54 properties in 19 municipalities of the state of Sergipe were collected and assayed using indirect fluorescent antibody test. The assay used antibodies against Toxoplasma gondii (IFAT-IgG) with a cutoff point of 1:64. We observed that 28.22% (263/932) of the ovine samples were serum-reactive. In a logistic regression, factors such as consumption of water directly from the source, consumption of water from a deep well, and age below 12 months were associated with protection; whereas factors such as presence of cats on the property, presence of slatted floor, and use of exchanged or borrowed breeding males were associated with infection. The studied area can be considered endemic for toxoplasmosis, so it is necessary to adopt preventive and control measures because this zoonotic infection poses risks to public health.
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This paper describes a computational model based on lumped elements for the mutual coupling between phases in transmission lines without the explicit use of modal transformation matrices. The self and mutual parameters and the coupling between phases are modeled using modal transformation techniques. The modal representation is developed from the intrinsic consideration of the modal transformation matrix and the resulting system of time-domain differential equations is described as state equations. Thus, a detailed profile ofthe currents and the voltages through the line can be easily calculated using numerical or analytical integration methods. However, the original contribution of the article is the proposal of a time-domain model without the successive phase/mode transformations and a practical implementation based on conventional electrical circuits, without the use of electromagnetic theory to model the coupling between phases. © 2003-2012 IEEE.
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A retrospective study of tumors in dogs was carried out in the School Veterinary Hospital (HVE), Eduardo Mondlane University, Mozambique, between January 2004 and January 2009. Data from clinical-surgical records of tumor samples surgically removed, necropsy and cytological exams were used and sent for histopathology exams. During the study 210 tumors and about 27 different types of tumors were identified. Skin tumors (61.0%) were the most frequent, followed by mammary gland tumors (27.60%), reproductive system tumors (11.90%) and bone system tumors. The mammary gland tumors were observed only in females, with high prevalence in bitches which were not spayed or spayed after two years old. It was concluded that the neoplasia prevalence increase was correlated to the higher longevity of dogs, and breed also contributed for the development of determined tumors due to high incidence of mastocitomas in Boxer and German Shepherd breeds. The 100 % incidence of mammary gland neoplasia in females confirmed the higher predisposition for mammary gland neoplasia in females.
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Noradrenergic neurons in the caudal ventrolateral medulla (CVLM; A1 group) contribute to cardiovascular regulation. The present study assessed whether specific lesions in the A1 group altered the cardiovascular responses that were evoked by hypertonic saline (HS) infusion in non-anesthetized rats. Male Wistar rats (280-340 g) received nanoinjections of antidopamine-β-hydroxylase-saporin (A1 lesion, 0.105 ng.nL-1) or free saporin (sham, 0.021 ng.nL-1) into their CVLMs. Two weeks later, the rats were anesthetized (2% halothane in O2) and their femoral artery and vein were catheterized and led to exit subcutaneously between the scapulae. On the following day, the animals were submitted to HS infusion (3 M NaCl, 1.8 ml • kg-1, b.wt., for longer than 1 min). In the sham-group (n = 8), HS induced a sustained pressor response (ΔMAP: 35±3.6 and 11±1.8 mmHg, for 10 and 90 min after HS infusion, respectively; P<0.05 vs. baseline). Ten min after HS infusion, the pressor responses of the anti-DβH-saporin-treated rats (n = 11)were significantly smaller(ΔMAP: 18±1.4 mmHg; P<0.05 vs. baseline and vs. sham group), and at 90 min, their blood pressures reached baseline values (2±1.6 mmHg). Compared to the sham group, the natriuresis that was induced by HS was reduced in the lesioned group 60 min after the challenge (196±5.5 mM vs. 262±7.6 mM, respectively; P<0.05). In addition, A1-lesioned rats excreted only 47% of their sodium 90 min after HS infusion, while sham animals excreted 80% of their sodium. Immunohistochemical analysis confirmed a substantial destruction of the A1 cell group in the CVLM of rats that had been nanoinjected withanti-DβH-saporin. These results suggest that medullary noradrenergic A1 neurons are involved in the excitatory neural pathway that regulates hypertensive and natriuretic responses to acute changes in the composition of body fluid. © 2013 da Silva et al.
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