979 resultados para Tendência secular


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We investigate the secular dynamics of three-body circumbinary systems under the effect of tides. We use the octupolar non-restricted approximation for the orbital interactions, general relativity corrections, the quadrupolar approximation for the spins, and the viscous linear model for tides. We derive the averaged equations of motion in a simplified vectorial formalism, which is suitable to model the long-term evolution of a wide variety of circumbinary systems in very eccentric and inclined orbits. In particular, this vectorial approach can be used to derive constraints for tidal migration, capture in Cassini states, and stellar spin–orbit misalignment. We show that circumbinary planets with initial arbitrary orbital inclination can become coplanar through a secular resonance between the precession of the orbit and the precession of the spin of one of the stars. We also show that circumbinary systems for which the pericenter of the inner orbit is initially in libration present chaotic motion for the spins and for the eccentricity of the outer orbit. Because our model is valid for the non-restricted problem, it can also be applied to any three-body hierarchical system such as star–planet–satellite systems and triple stellar systems.

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Secular trends in height and weight are reasonably well documented in Europe. Corresponding observations for skeletal maturation are lacking. Aim: To assess secular trends in height, body mass and skeletal maturity of Portuguese children and adolescents and to provide updated reference values for skeletal maturity scores (SMSs). Subjects and methods: Data for 2856 children and adolescents of 4–17 years, 1412 boys and 1444 girls, from The ‘Madeira Growth Study’ (MGS; 1996–1998) and from the‘Healthy Growth of Madeira Children Study’ (CRES; 2006) were used. Height and body mass were measured. Skeletal maturity was assessed with the Tanner-Whitehouse 2 and 3 methods. Results: Children from CRES were taller and heavier than peers from MGS. Differences in height reached 5.8cm in boys and 5.5cm in girls. RUS SMSs did not differ consistently between surveys boys, while higher RUS scores were observed in CRES girls. Adult RUS SMSs for MGS and CRES combined were attained at 15.8 years in boys and 14.8 years in girls. Corresponding ages for adult Carpal SMSs were 14.4 and 14.0, respectively. Conclusion: The short-term trends for height and mass were not entirely consistent with the trends in RUS and Carpal SMSs and SAs.

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Secular trends in height and weight are reasonably well documented in Europe. Corresponding observations for skeletal maturation are lacking. Aim: To assess secular trends in height, body mass and skeletal maturity of Portuguese children and adolescents and to provide updated reference values for skeletal maturity scores (SMSs). Subjects and methods: Data for 2856 children and adolescents of 4–17 years, 1412 boys and 1444 girls, from The ‘Madeira Growth Study’ (MGS; 1996–1998) and from the‘Healthy Growth of Madeira Children Study’ (CRES; 2006) were used. Height and body mass were measured. Skeletal maturity was assessed with the Tanner-Whitehouse 2 and 3 methods. Results: Children from CRES were taller and heavier than peers from MGS. Differences in height reached 5.8cm in boys and 5.5cm in girls. RUS SMSs did not differ consistently between surveys boys, while higher RUS scores were observed in CRES girls. Adult RUS SMSs for MGS and CRES combined were attained at 15.8 years in boys and 14.8 years in girls. Corresponding ages for adult Carpal SMSs were 14.4 and 14.0, respectively. Conclusion: The short-term trends for height and mass were not entirely consistent with the trends in RUS and Carpal SMSs and SAs.

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Foi realizado com o objetivo de avaliar a tendência do uso de fungicida para o controle da brusone (Pyricularia oyrzae Cav.) do arroz, no período de 1967 a 1975, no Brasil.

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Recibido 05 de mayo de 2010 • Aceptado 24 de junio de 2010 • Corregido 05 de agosto de 2010      Resumen. Con base en el aporte del crítico literario y pensador palestino Said (1983), quien acuña el término “crítica secular,” este artículo analiza la posibilidad de aplicar dicho concepto a la enseñanza de la literatura, tanto en niveles de educación primaria y secundaria, como en niveles superiores. Por crítica secular se debe entender el modo de análisis textual que ve a la literatura inherentemente ligada a las experiencias humanas, a las realidades sociales de los contextos en que es producida y a las instituciones de poder que la propician o la reprimen. La principal propuesta será, entonces, el plantear una metodología para abordar, en el salón de clase, los textos literarios desde una perspectiva mundana; es decir, ligándolos al mundo exterior, al que está fuera de las aulas. En este sentido, y utilizando tanto ejemplos textuales primarios como teoría literaria, el artículo propondrá convertir el estudio de la literatura en una herramienta de análisis, cuestionamiento, desafío y cambio de las realidades que la producen.

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Para avaliar a tendência de consumo, foram considerados os anos compreendidos entre 1990 e 2001, divididos em dois períodos. No primeiro período, o consumo de vinhos de mesa, elaborados a partir de uvas americanas e híbridas, apresentou uma taxa negativa de crescimento. No segundo período, o consumo destes vinhos apresentou uma taxa de crescimento de 6,7 % ao ano. Esta categoria de vinho não sofre a concorrência do importado. Na categoria vinhos finos, somando os nacionais com os importados, houve um decréscimo de 2,7%, no consumo no último período. Enquanto o consumo de vinhos finos nacionais apresentou um decréscimo anual de 6,7 % , o de importados teve um crescimento de 3,5% ao ano. O consumo de vinhos espumantes (nacionais e importados) exibiu uma taxa de crescimento de 17,8% ao ano, no segundo período. Destes, o consumo de espumantes importados cresceu 18,3% e o de espumantes nacionais 17,6%.

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CONTEXT: Intestinal constipation - a common symptom among the general population - is more frequent in women. It may be secondary to an improper diet or organic or functional disturbances, such as dyskinesia of the pelvic floor. This is basically characterized by the absence of relaxation or paradoxical contraction of the pelvic floor and anal sphincter during evacuation. OBJECTIVE: To analyze, by manometric data, the anal pressure variation at rest, during evacuation effort by using the Valsalva maneuver and forced post-expiratory apnea in subjects with secondary constipation. METHODS: Twenty-one patients (19 females - 90.4%) with a mean age of 47.5 years old (23-72) were studied. The diagnosis was performed using anorectal manometry, with a catheter containing eight channels disposed at the axial axis, measuring the proximal (1) and distal (2) portions of the anal orifice. The elevation of the pressure values in relation to the resting with the evacuation effort was present in all patients. The Agachan score was used for clinical evaluation of constipation. The variables studied were: mean anal pressure of the anal orifice for 20 seconds at rest, the effort of evacuation using Valsalva maneuver and the effort of evacuation during apnea after forced expiration, as well as the area under the curve of the manometric tracing at moments Valsalva and apnea. RESULTS: The analysis of the mean values of the anal pressure variation at rest evidenced difference between proximal and distal channels (P = 0.007), independent of the moment and tendency to differ during moments Valsalva and apnea (P = 0.06). The mean of values of the area under the manometric tracing curve showed differences between moments Valsalva and apnea (P = 0.0008), either at the proximal portion or at the distal portion of the anal orifice. CONCLUSION: The effort of evacuation associated with postexpiratory apnea, when compared with the effort associated with the Valsalva maneuver, provides lower elevation of anal pressure at rest by the parameter area under the curve.

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Studies in several countries have shown the occurrence of forest transition, when forest cover increase overcomes the loss by deforestation. In Brazil, although deforestation is still higher than afforestation, this relationship may be inverse in some regions. Recent assessments suggest the tendency of the state of São Paulo towards forest transition. Aiming to analyze forest transition evidence and facilitate the use of existing information, we review data on native vegetation cover variation in São Paulo from four data sources (Instituto Florestal, SOS MataAtlântica/INPE, IBGE and CATI/IEA). Our results indicate that discrepancies among these assessments may be accounted by differences in methodologies and objectives. We highlight their common grounds and discuss possibilities to harmonize their information.

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The field activities are essential for the education of a good taxonomist. The most common problems found in field activities are: a) large number of students, b) heterogeneous educational background and unlevelled knowledge of the participants, c) repetitions and tendency of collecting the more evidents life-forms. The causes and consequences of such problems are discussed herein. The proposed solution is a methodology, based on many years of experience in field courses for undergraduate and graduate courses. Topics about the ideal number of participants, area of coverage, period of activity, division of work and the necessary material and equipment are discussed. According to the number of species collected at the same place, this methodology may result in a list of local species with precise information about the life-forms, habitat, common names, frequency, uses, phenology and further information in this kind of work. The results of the aplication of this metodology in a field course held in the region of Ubatuba-SP are presented.

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In this paper, I argue against the contemporary tendency to confine ideology to the sphere of subjectivity and point of view, as defended by Paul Simpson (1993) in his book Language, Ideology, and Point of View. My principal criticism against the view is that it simply amounts to a re-affirmation of certain of the conceptual categories with which we have for long been accustomed to think. Rather, I contend, we ought to try to interrogate those very categories with a view to teasing out the instabilities that characterise them. I argue that there is an urgent need to deconstruct the very opposition between ideology, point of view etc. on the one hand, and science, theory, or whatever that one might wish to posit on the other.

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One of the effects of the globalized world is a strong tendency to eliminate differences, promoting a planetary culture. Education systems are particularly affected, undergoing strong pressure from international studies and evaluations, inevitably comparative, and sadly competitive. As a result, one observes the gradual elimination of cultural components in the definition of education systems. The constitution of new social imaginaries becomes clear; imaginaries empty of historical, geographical and temporal referents, characterized by a strong presence of the culture of the image. The criteria of classification establish an inappropriate reference that has as its consequence the definition of practices and even of education systems. On the other hand, resistance mechanisms, often unconscious, are activated seeking to safeguard and recover the identifying features of a culture, such as its traditions, cuisine, languages, artistic manifestations in general, and, in doing so, to contribute to cultural diversity, an essential factor to encourage creativity. In this article, the sociocultural basis of mathematics and of its teaching are examined, and also the consequences of globalization and its effects on multicultural education. The concept of culture is discussed, as well as issues related to culture dynamics, resulting in the proposition of a theory of transdisciplinar and transcultural knowledge. Upon such basis the Ethnomathematics Program is presented. A critique is also made of the curriculum presently used, which is in its conception and detailing, obsolete, uninteresting and of little use. A different concept of curriculum is proposed, based on the communicative (literacy), analytical (matheracy), and material (technoracy) instruments.

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Quality traits of boneless rib cut (L. dorsi muscle) from Nelore young bulls. To study the meat quality traits of Nelore breed young bulls, and the effect of age (690-780 days) on them, 113 animals were slaughtered after 109 days of intensive feeding with 20% concentrate and 80% roughage. All the carcasses were graded at the slaughter floor by the Federal Inspection and chilled for 24 hours (Tinitial=5°C, Tfinal=2°C). Fifty one half carcasses (right side), type B - B R A S I L `s grading system - from animals of 23 to 26 months were boned and separated into commercial cuts. Two steaks (2.5cm thick) were removed from each boneless rib cut (m. L. dorsi), vacuum packaged and aged for 7 days (0-2°C). The pH varied from 5.44 to 5.83 and only two samples had pH ³ 5.70. The L* (brightness) average value was 34.85. The water and fat content were 75.65% and 1.71%, respectively. The average WB shear force was 6.70kg, and it was not affected by age (690-734 days), but presented a trend (t test, p=0.22) for increasing values between 735 and 780 days. Animal age did not affect other quality traits (t test, p>0.20). It was concluded that the rib cut from Nelore young bulls may not have a good acceptability in exigent markets, and that carcasses graded B, presumed to be the best grade, do not necessarily present the best meat quality characteristics.

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INTRODUCTION:proctocolectomy with ileal pouch-anal anastomosis (IPAA) is the standard surgical procedure for the treatment of ulcerative colitis (UC) and is associated with the prospect of cure. Experience gained over the years has demonstrated the occurrence of a high number of complications as well as bowel disorders that can compromise quality of life (QoL).OBJECTIVE:evaluate QoL in patients with IPAA for ulcerative colitis.PATIENTS AND METHODS:the Inflammatory Bowel Disease Questionnaire (IBDQ) was used to assess QoL in patients with IPAA after its validation in Portuguese.RESULTS:thirty-one patients submitted to IPAA by the same group of professionals were evaluated. QoL was classified as regular in all domains evaluated (intestinal and systemic symptoms and emotional and social aspects). There were no differences in relation to gender, type of pouch or postoperative time. However, elderly patients showed a tendency toward lower scores. Having a professional activity was associated with higher scores in systemic symptoms and social aspects (p < 0.05). Patients with ileostomy showed lower values in the domains of systemic symptoms, emotional and social aspects (p <0.05).CONCLUSION:in all domains assessed, patients with IPAA for UC had QoL classified as regular. Ileostomy and lack of professional activity negatively influenced QoL.