907 resultados para Third orders
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Consider a finite body of mass m (C1) with moments of inertia A, B and C. This body orbits another one of mass much larger M (C2), which at first will be taken as a point, even if it is not completely spherical. The body C1, when orbit C2, performs a translational motion near a Keplerian. It will not be a Keplerian due to external disturbances. We will use two axes systems: fixed in the center of mass of C1 and other inertial. The C1 attitude, that is, the dynamic rotation of this body is know if we know how to situate mobile system according to inertial axes system. The strong influence exerted by C2 on C1, which is a flattened body, generates torques on C1, what affects its dynamics of rotation. We will obtain the mathematical formulation of this problem assuming C1 as a planet and C2 as the sun. Also applies to case of satellite and planet. In the case of Mercury-Sun system, the disturbing potential that governs rotation dynamics, for theoretical studies, necessarily have to be developed by powers of the eccentricity. As is known, such expansions are delicate because of the convergence issue. Thus, we intend to make a development until the third order (superior orders are not always achievable because of the volume of terms generated in cases of first-order resonances). By defining a modern set of canonical variables (Andoyer), we will assemble a disturbed Hamiltonian problem. The Andoyer's Variables allow to define averages, which enable us to discard short-term effects. Our results for the resonant angle variation of Mercury are in full agreement with those obtained by D'Hoedt & Lemaître (2004) and Rambaux & Bois (2004)
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We study two 3-3-1 models with (i) five (four) charge 2/3 (-1/3) quarks and (ii) four (five) charge 2/3 (-1/3) quarks and a vectorlike third generation. Possibilities beyond these models are also briefly considered.
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Ectopic third molar teeth are those that are impacted in unusual positions, or that have been displaced and are at a distance from their normal anatomic location. Ectopic eruption of a tooth within the oral cavity is common, but rare in other sites. Ectopic eruption can be associated with developmental disturbances, pathologic processes or iatrogenic activity. Male, 19- years old, with an upper left ectopic third molar located in the maxillary sinus-infraorbital region. The patient reported a bad taste and recurrent sinusitis that had been resistant to treatment. Surgical excision was carried out of the third molar tooth using the Caldwell-Luc approach.
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Pós-graduação em Saúde Coletiva - FMB
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Drawing on longitudinal data from the Early Childhood Longitudinal Study, Kindergarten Class of 1998–1999, this study used IRT modeling to operationalize a measure of parental educational investments based on Lareau’s notion of concerted cultivation. It used multilevel piecewise growth models regressing children’s math and reading achievement from entry into kindergarten through the third grade on concerted cultivation and family context variables. The results indicate that educational investments are an important mediator of socioeconomic and racial/ethnic disparities, completely explaining the black-white reading gap at kindergarten entry and consistently explaining 20 percent to 60 percent and 30 percent to 50 percent of the black-white and Hispanic-white disparities in the growth parameters, respectively, and approximately 20 percent of the socioeconomic gradients. Notably, concerted cultivation played a more significant role in explaining racial/ethnic gaps in achievement than expected from Lareau’s discussion, which suggests that after socioeconomic background is controlled, concerted cultivation should not be implicated in racial/ethnic disparities in learning.
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All Latin students eventually have a problem with qui. To solve it, they need a third qui in their quiver. The problem shows up when they advance into third year, transitioning from Caesar to Roman Comedy, or to the poets. The familiar “who” often leads to nonsense, and they are at a loss. There are three qui’s: the relative pronoun, the interrogative adjective, and the old ablative instrumental, e.g. 1. qui dixit, who spoke 2. qui vir, which man 3. illud qui, that thing by means of which It is the third that causes problems. So this article addresses the question “how do you tell qui from qui ?” There are six main ways to tell when to say “how,” “whereby,” or “the way” for qui: 1. The whereby/how qui is usually interrogative. 2. It is often marked further by being paired with a following quia: qui? quia “How . . . ? Because . . .” 3. The most frequent associated idea is of knowing, with a form of scire or gnoscere: qui scis, qui noveris? “How do you know?” 4. Qui followed immediately by an adverb or comparative is whereby/how/the way: qui minus quam . . . “How less than . . .” 5. The obvious noun antecedent is not a person, but a tool: machinas qui, “tools to __ with” (“with which to__”). 6. If the context is of giving or seeking, qui is instrumental, “how,” “a way,” “the means, “ e.g. da mi qui comparem “Give me the means to buy . . .” There is no antecedent.
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We investigated the cardiovascular effects of the microinjection of L-proline (L-Pro) into the third ventricle (3V) and its peripheral mechanisms. Different doses of L-Pro into the 3V caused dose-related pressor and bradycardiac responses. The pressor response to L-Pro injected into the 3V was potentiated by intravenous pretreatment with the ganglion blocker pentolinium (5 mg/kg), thus excluding any significant involvement of the sympathetic nervous system. Because the response to the microinjection of L-Pro into the 3V was blocked by intravenous pretreatment with the V1-vasopressin receptor antagonist dTyr(CH2)5(Me)AVP (50 mu g/kg), it is suggested that these cardiovascular responses are mediated by a vasopressin release. The pressor response to the microinjection of L-Pro into the 3V was found to be mediated by circulating vasopressin, so, given that the paraventricular nucleus of the hypothalamus (PVN) is readily accessible from the 3V, we investigated whether the PVN could be a site of action for the L-Pro microinjected in the 3V. The microinjection of L-Pro (0.033 mu moles/0.1 mu l) into the PVN caused cardiovascular responses similar to those of injection of the 3V and were also shown to be mediated by vasopressin release. In conclusion, these results show that the microinjection of L-Pro into the 3V causes pressor and bradycardiac responses that could involve stimulation of the magnocellular cells of the PVN and release of vasopressin into the systemic circulation. Also, because the microinjection of L-Pro into the PVN caused a pressor response, this is the first evidence of cardiovascular effects caused by its injection in a supramedullary structure. (c) 2012 Wiley Periodicals, Inc.
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Purpose: The aim of this study was to verify possible associations between oral health-related quality of life (QoL) and the position of the lower third molar among patients undergoing lower third molar surgery during the first postoperative week. Materials and Methods: We performed an interventional prospective study of 86 patients for whom the preoperative treatment plan included the removal of 2 third molar teeth from the same side in a 1-time procedure. The patients were divided into 2 groups depending on the position of the lower third molar. QoL was evaluated before and after the surgical procedure (during the first 7 days) with the Oral Health Impact Profile (OHIP) 14 questionnaire. Data were treated according to Stata 10.0 (StataCorp, College Station, TX). Variables were evaluated by use of split-plot analysis of variance for the repeated-measures analysis to identify the association between QoL and the position of the lower third molar. Results: Patients can have deterioration in their QoL immediately after surgery, especially during the first and second postoperative days, and subsequently show rapid improvement. The variation in the total OHIP score during the days after surgery was significant, whereas a decrease in QoL was observed immediately after the procedure (P = .001), which returned to initial value (preoperative) levels after the sixth postoperative day. The OHIP domains with higher scores (ie, those that had an impact) were physical pain, psychological discomfort, and physical disability (domains 2, 3, and 4, respectively). Conclusions: Teeth considered to be associated with technical difficulties for extraction based on their position had a higher score on the OHIP-14 questionnaire and worse health-related QoL score. QoL outcomes may be as important as clinical signs in decisions regarding third molar extractions. (C) 2012 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 70:779-786, 2012
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Objectives. This study recorded and evaluated the intra-and inter-group agreement degree by different examiners for the classification of lower third molars according to both the Winter's and Pell & Gregory's systems. Study Design. An observational and cross-sectional study was realized with forty lower third molars analyzed from twenty digital panoramic radiographs. Four examiner groups (undergraduates, maxillofacial surgeons, oral radiologists and clinical dentists) from Aracaju, Sergipe, Brazil, classified them in relation to angulation, class and position. The variance test (ANOVA) was applied in the examiner findings with significance level of p<0.05 and confidence intervals of 95%. Results. Intra- and inter-group agreement was observed in Winter's classification system among all examiners. Pell & Gregory's classification system showed an average intra-group agreement and a statistical significant difference to position variable in inter-group analysis with greater disagreement to the clinical dentists group (p<0.05). Conclusions. High reproducibility was associated to Winter's classification, whereas the system proposed by Pell & Gregory did not demonstrate appropriate levels of reliability.
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This study investigated the immunodetection of PTCH in epithelial components of dental follicles associated with impacted third molars without radiographic signs of pathosis. One hundred and five specimens of dental follicles associated with impacted third molars with incomplete rhizogenesis (between Nolla's stage 6 and 9) were surgically removed from 56 patients. Epithelial cell proliferation was determined by using immunohistochemical labeling. Statistical analysis was performed using Fisher exact test and a level of significance of 5%. Of the 105 dental follicles collected, 3 were PTCH-positive. The specimens with squamous metaplasia and epithelial hyperplasia had higher rates of positivity for PTCH, as well as those with active remnants of odontogenic epithelium. This study suggests that the odontogenic cells of the dental follicle might be proliferating during the rhizogenesis, while the squamous metaplasia and hyperplasia of the epithelial lining and proliferative odontogenic epithelial rests show the differentiation potential of dental follicles.
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This work reports on the spectral dependence of both nonlinear refraction and absorption in lead-germanium oxide glasses (PbO-GeO2) containing silver nanoparticles. We have found that this material is suitable for all-optical switching at telecom wavelengths but at the visible range it behaves either as a saturable absorber or as an optical limiter. (C) 2012 Optical Society of America
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Third harmonic generation (THG) has been studied in europium selenide EuSe in the vicinity of the band gap at 2.1-2.6 eV and at higher energies up to 3.7 eV. EuSe is amagnetic semiconductor crystalizing in centrosymmetric structure of rock-salt type with the point group m3m. For this symmetry the crystallographic and magnetic-field-induced THG nonlinearities are allowed in the electric-dipole approximation. Using temperature, magnetic field, and rotational anisotropy measurements, the crystallographic and magnetic-field-induced contributions to THG were unambiguously separated. Strong resonant magnetic-field-induced THG signals were measured at energies in the range of 2.1-2.6 eV and 3.1-3.6 eV for which we assign to transitions from 4 f(7) to 4 f(6)5d(1) bands, namely involving 5d(t(2g)) and 5d(e(g)) states.
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Forensic age estimation is an important element of anthropological research, as it produces one of the primary sources of data that researchers use to establish the identity of a person living or the identity of unknown bodily remains. The aim of this study was to determine if the chronology of third molar mineralization could be an accurate indicator of estimated age in a sample Brazilian population. If so, mineralization could determine the probability of an individual being 18 years or older. The study evaluated 407 panoramic radiographs of males and females from the past 5 years in order to assess the mineralization status of the mandibular third molars. The evaluation was carried out using an adaptation of Demirjian's system. The results indicated a strong correlation between chronological age and the mineralization of the mandibular third molars. The results indicated that modern Brazilian generation tends to demonstrate an earlier mandibular third molar mineralization than older Brazilian generation and people of other nationalities. Males reached developmental stages slightly earlier than females, but statistically significant differences between the sex were not found. The probability that an individual with third molar mineralization stage H had reached an age of 18 years or older was 96.8-98.6% for males and females, respectively. (C) 2011 Elsevier Ireland Ltd. All rights reserved.
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Fetal tissues are frequently discarded before (amniocentesis) or after birth, which both facilitates stem cell access and helps to overcome ethical concerns. In the present study, we aimed to isolate and characterize stem cells from the allantoic and amniotic fluids (ALF; AMF) of third trimester canine fetuses. This gestation age has not been previously explored for stem cells isolation. The gestational age, cell culture conditions and method of isolation used in this study allowed for the establishment and efficient expansion of ALF and AMF cells. We showed that the majority of ALF and ALF cells express the stem cell markers, such as vimentin, nestin and cytokeratin 18 (CK18). Under appropriate culture conditions AMF derived cells can undergo differentiation into osteogenic, adipogenic, chondrogenic and neuron-like lineages. ALF derived cells showed adipogenic, and chondrogenic potential. Therefore, ALF and AMF cells derived at the third gestation trimester can be qualified as progenitor stem cells, accordingly referred as (alantoic fluid progenitor/stem) ALF PS cells and (amniotic fluid progenitor/stem) AMF PS cells. (C) 2012 Elsevier Ltd. All rights reserved.