936 resultados para paleogeographical and paleoecological significance


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Regression analyses of a long series of light-trap catches at Narrabri, Australia, were used to describe the seasonal dynamics of Helicoverpa armigera (Hubner). The size of the second generation was significantly related to the size of the first generation, to winter rainfall, which had a positive effect, and to spring rainfall which had a negative effect. These variables accounted for up to 96% of the variation in size of the second generation from year to year. Rainfall and crop hosts were also important for the size of the third generation. The area and tonnage of many potential host crops were significantly correlated with winter rain. When winter rain was omitted from the analysis, the sizes of both the second and third generations could be expressed as a function of the size of the previous generation and of the areas planted to lucerne, sorghum and maize. Lucerne and maize always had positive coefficients and sorghum a negative one. We extended our analysis to catches of H. punctigera (Wallengren), which declines in abundance after the second generation. Winter rain had a positive effect on the sizes of the second and third generations, and rain in spring or early summer had a negative effect. Only the area grown to lucerne had a positive effect on abundance. Forecasts of pest levels from a few months to a few weeks in advance are discussed, along with the improved understanding of the seasonal dynamics of both species and the significance of crops in the management of insecticide resistance for H. armigera.

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Visual pigments, the molecules in photoreceptors that initiate the process of vision, are inherently dichroic, differentially absorbing light according to its axis of polarization. Many animals have taken advantage of this property to build receptor systems capable of analyzing the polarization of incoming light, as polarized light is abundant in natural scenes (commonly being produced by scattering or reflection). Such polarization sensitivity has long been associated with behavioral tasks like orientation or navigation. However, only recently have we become aware that it can be incorporated into a high-level visual perception akin to color vision, permitting segmentation of a viewed scene into regions that differ in their polarization. By analogy to color vision, we call this capacity polarization vision. It is apparently used for tasks like those that color vision specializes in: contrast enhancement, camouflage breaking, object recognition, and signal detection and discrimination. While color is very useful in terrestrial or shallow-water environments, it is an unreliable cue deeper in water due to the spectral modification of light as it travels through water of various depths or of varying optical quality. Here, polarization vision has special utility and consequently has evolved in numerous marine species, as well as at least one terrestrial animal. In this review, we consider recent findings concerning polarization vision and its significance in biological signaling.

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Purpose: To evaluate overall and relapse-free survival (RFS) in patients with nonmycosis fungoides (non-MF) primary cutaneous lymphoma (PCL). Methods: Thirty-eight patients with PCL excluding cases of MF treated between 1993 and 2006 were analyzed retrospectively. Survival statistics were estimated by the methods of Kaplan and Meier, and univariate and multivariate significance testing were performed by Cox regression analysis. Results: The median follow-up was 34.6 months (range, 2-138.3 months). The overall survival for the entire study population, at 5 and 10 years, was 97% and 78%, respectively. The RFS for the entire study population, at 5 and 10 years, was 30% and 22%, respectively. For those who received radiotherapy (RT) as a component of their initial therapy, the RFS at 5 and 10 years was 48% and 36%, respectively. Among those receiving RT who relapsed, the site of relapse was out-of-field in 82% of the cases. In our multivariate analysis, only RT as a component of the initial therapy and the absence of bulky disease had a statistically significant improvement in RFS (P = 0.01 and < 0.01, respectively). Conclusion: RT improves the local control and RFS of patients with non-MF PCL.

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The aim of this study was to create an adaptation of the Revised Knox Preschool Play Scale (RKPPS) for the Brazilian population, as well as to apply the instrument with statistical analysis to verify the preliminary intra-rater and inter-rater reliability and repeatability of the instrument. The instructions presented by Beaton et al. regarding adaptation of instruments were followed to perform a cross-cultural adaptation of the RKPPS. A preliminary test of the Portuguese version was performed on 18 children with no motor, cognitive or sensory impairment. The video recordings of this administration were analysed on two separate occasions by two examiners within a 5-month interval, using the scores suggested by Pfeifer. The Spearman`s test was used in the statistical analysis of the obtained data. The author of the RKPPS agreed with the small necessary cultural adaptations. The Spearman test revealed a high correlation coefficient and good significance levels for both intra- and inter-raters values. This study demonstrated the reliability and repeatability of the Brazilian version of the RKPPS. This is a preliminary study and further studies are needed in order to validate the scale to be administered in the Brazilian population. Copyright (C) 2010 John Wiley & Sons, Ltd.

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Oral squamous cell carcinoma (OSCC) accounts for more than 95% of all malignant neoplasms in the oral cavity. Although several studies have shown the epidemiology of this cancer in Brazil, there do not seem to be any studies that describe the prognostic factors related to OSCC in the Amazon region. Therefore, the aim of this study was to determine the survival rate and prognostic significance of different factors in patients from this region affected by OSCC. Data from 85 patients with histologically confirmed squamous cell carcinoma of the tongue and floor of the mouth identified from the Ofir Loyola Hospital archives were collected and analyzed using univariate (log-rank test) and multivariate (Cox proportional hazard model) tests. The overall 5-year survival rate was found to be 27%. Univariate analysis showed that the 5-year survival rate was significantly higher for younger (<= 45 y) female patients, patients with T1-2 tumors and clinically clear neck nodes (N0), patients with early stage cancers (AJCC stage I-II), and patients treated with surgical procedures. However, multivariate analysis showed that the 5-year survival rate was significantly higher only in the younger patients and those who underwent surgical treatment. The age of the patient at the moment of diagnosis and treatment with surgical procedures were the only independent prognostic factors that affected the 5-year survival rate of the patients in this region.

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This article represents the proceedings of a workshop at the 2000 ISBRA Meeting in Yokohama, Japan. The chairs were Geoffrey M. Thiele and Simon Worrall. The presentations were (1) The chemistry of malondialdehyde-acetaldehyde (MAA) adducts, by Dean J. Tuma; (2) The formation and clearance of MAA adducts in ethanol-fed rats, by Simon Worrall; (3) Immune responses to MAA adducts may play a role in the development of alcoholic liver disease, by Lynell W. Klassen; (4) Unique biological responses to MAA-modifled proteins that may play a role in the development and/or progression of alcoholic liver disease, by Geoffrey M. Thiele; (5) MAA-adducted bovine serum albumin activates protein kinase C and stimulates interleukin-8 release in bovine bronchial epithelial cells, by Todd A. Wyatt; and (6) An enzyme immune assay for serum antiacetaldehyde adduct antibody using low-density lipoprotein-adduct and its significance in alcoholic liver injury and ALDH2 heterozygotes, by Naruhiko Nagata.

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For most of us, the modern city is somewhat unintelligible, both in terms of its structure and its significance. As an urbanised population, the city should be our natural territory, but the pace and scope of its change leads to an illegibility of its form and character. There is infinite, seemingly significant, activity - demolition, building and makeover - but there is little sense of the city as a site of meaning.

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Protease-activated receptors type 2 (PAR2) are activated by serine proteases like trypsin and mast cell tryptase. The function and physiological significance of PAR2 receptors is poorly understood, but recent studies suggest a role during inflammatory processes in both airways and intestine. PAR2 receptors are also likely to participate in the control of ion transport in these tissues. We demonstrate that stimulation of PAR2 in airways and intestine significantly enhanced ion transport. Trypsin induced CI- secretion in both airways and intestine when added to the basolateral but not to the luminal side of these tissues. In both airways and intestine, stimulation of ion transport was largely dependent on the increase in intracellular Ca2+. Effects of trypsin were largely reduced by basolateral bumetanide and barium and by trypsin inhibitor. Thrombin, an activator of proteinase-activated receptors types 1, 3, and 4 had no effects on equivalent short-circuit current in either airways or intestine. Expression of PAR2 in colon and airways was further confirmed by reverse transcription-polymerase chain reaction. We postulate that these receptors play a significant role in the regulation of electrolyte transport, which might be important during inflammatory diseases of airways and intestine.

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Because of the distance in time and the lack of testifying documents, one should be extremely careful when labelling portraits in medieval books of hours as donor portraits or owner portraits. There are, however, manuscripts that reveal their first owner within their decorative programme, and the Lamoignon Hours (Lisbon, Gulbenkian, ms LA 237) is one of these. This article aims to discuss the iconography of the three portraits found on f.165v, f.202v and f.286v, as well as the relevance of portraiture and heraldic insignia in books of hours and the significance of such content to the original owner and to those who possessed the book afterwards.

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ABSTRACT Nodal glands are found in one third of the Polygalaceae genera and have valuable taxonomic, ecological and evolutionary significance. In Brazil, they occur in five of the eleven genera already registered. However, there is still a controversy regarding the origin of these structures. The objective of this study was to characterize the morphology and the origin of nodal glands inCaamembeca spectabilis, in order to increase the structural and functional knowledge of these glands in the genera. Samples of nodal regions were collected, fixed and processed according to the methods of light microscopy and electron scanning. Ants were observed and identified along the stem axis. The glucose in exudate allows us to classify these glands as extrafloral nectaries. They are located in pairs on the nodal region. However, its origin is in the leaf trace. In the longitudinal section, the nectaries were present in the apex of cells with anticlinal walls impregnated with suberin, which represents the first record for the family. In this region there is also the formation of a hole by lysis. The secretory tissue is surrounded by phloem. Xylem vessels were observed only on the basis of the nectary, where there are also idioblasts with crystals in druse type. We have studied the ontogeny of the glands nodal in Caamembeca spectabilis and unveiled that these glands are linked to the leaves as stipular nectaries. In addition, the new findings presented here may add support for the understanding of morphology and anatomy of nodal glands in Caamembeca.

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In recent years research explored different acupuncture stimulation techniques but interest has focused primarily on somatic acupuncture and on a limited number of acupoints. As regards ear Acupuncture (EA) there is still some criticism about the clinical specificity of auricular points/areas representing organs or structures of the body. The aim of this study was to verify through (Functional magnetic resonance imaging) fMRI the hypothesis of EA point specificity using two auricular points having different topographical locations and clinical significance. Six healthy volunteers underwent two experimental fMRI sessions: the first was dedicated to the stimulation of Thumb Auricular Acupoint (TAA) and the second to the stimulation of Brain Stem Auricular Acupoint (BSAA). The stimulation of the needle placed in the TAA of the left ear produced an increase in activation bilaterally in the parietal operculum, region of the secondary somatosensory area SII. Stimulation of the needle placed in the BSAA of the left ear showed a pattern that largely overlapped regions belonging to the pain matrix, as shown to be involved in previous somatic acupuncture studies but with local differences in the left amygdala, anterior cingulate cortex, and cerebellum. The differences in activation patterns between TAA and BSAA stimulation support the specificity of the two acupoints. Moreover, the peculiarity of the regions involved in BSAA stimulation compared to those involved in the pain matrix, is in accordance with the therapeutic indications of this acupoint that include head pain, dizziness and vertigo. Our results provide preliminary evidence on the specificity of two auricular acupoints; further research is warranted by means of fMRI both in healthy volunteers and in patients carrying neurological/psychiatric syndromes.

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This paper forms part of a wider project to show the significance of archival material on distinguished economists, in this case Lauchlin Currie (1902-93), who studied and taught at Harvard before entering government service at the US Treasury and Federal Reserve Board as the intellectual leader of Roosevelt’s New Deal, 1934-39, as FDR’s White House economic adviser in peace and war, 1939-45, and as a post-war development economist. It discusses the uses made of the written and oral material available when the author was writing his intellectual biography of Currie (Duke University Press 1990) while Currie was still alive, and the significance of the material that has come to light after Currie’s death.

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Background: The metabolic syndrome (MS) represents a cluster of metabolic disorders that predicts diabetes and cardiovascular disease. Several definitions exist and further descriptive and prospective data are needed to compare these definitions and their significance in different populations. Objective: We examined, in a country of the African region, i) the prevalence of MS according to three major definitions (ATP, IDF, WHO); ii) the contribution of individual MS components; and iii) the agreement between the three considered definitions. We also examined the prevalence among diabetics and non-diabetics. Methods: We conducted an examination survey in a sample representative of the general population aged 25-64 of the Seychelles (Indian Ocean, African region), attended by 1255 persons (participation rate of 80.2%). Results: The prevalence of MS was similar with either definition of MS in men (24%--25%) but differed in women (WHO: 25%, ATP: 32%; IDF: 35%). Upon exclusion of diabetic persons, the prevalence was 5-10% lower for all three MS definitions: most diabetic persons had MS although a substantial proportion of diabetic men aged 45--64 did not have MS. The following components were found most often among persons with MS: 90% had high blood pressure (HBP) and 78% had obesity (ATP); 95% had obesity and 84% had HBP (WHO), and 89% had HBP and 75% had impaired glucose regulation (IDF) - not considering impaired glucose regulation and obesity that are compulsory components of the WHO and IDF definitions, respectively. Among persons with MS based on either of the three definitions (37% of total population), less than 80% met both ATP and IDF criteria, 67% both WHO and IDF criteria, 54% both WHO and ATP criteria and only 37% met all three definitions. Conclusion: We found a fairly high prevalence of MS in an African population. However, because there was only poor agreement between the 3 MS definitions, the fairly similar proportions of MS based on ATP, IDF or WHO definitions identified, to a substantial extent, different subjects as having MS.

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BACKGROUND: Drusen of the optic disc are associated with slowly progressive optic neuropathy, characterized by accumulation of acellular laminated concretions in the prelaminar portion of the optic nerve. Papillary hemorrhages and vascular shunts have been reported with disc drusen but their frequency and clinical significance is not well known. METHODS: Retrospective study of fundus photographs of 116 patients with disc drusen referred to the National Hospital for Neurology and Neurosurgery, London, between 1965 and 1991. RESULTS: Hemorrhages were found in 23 eyes from 16/116 (13.8%) patients. Most cases (68.8%, 11/16 cases) occurred in patients with buried drusen, and most hemorrhages were deeply located. Vascular shunts were present in 6.9% (8/116 cases), most frequently in patients with exposed drusen (6/8 cases), most being of the venous type (7/8 cases). DISCUSSION: Vascular anomalies are not rare in disc drusen, as 20.7% (24/116 cases) of our patients presented either disc hemorrhages or shunt vessels. Their presence supports the hypothesis of the slowly progressive nature of disc drusen and the more advanced stage of optic neuropathy in such eyes.

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The lengths of the male genital filaments and female spermathecal ducts were measured in phlebotomine sand flies of the Lutzomyia intermedia species complex and the ratios between these characters calculated. Ratios for L. intermedia s. s. from Northeast vs Southeast Brazil (Espírito Santo and Minas Gerais), Espírito Santo/Minas Gerais vs Rio de Janeiro/São Paulo and L. intermedia vs L. neivai were significantly different at P < 0.1, 0.05 and 0.01 respectively when compared using ANOVA. The spermathecal ducts and genital filaments of L. intermedia were significantly longer than those of L. neivai (P < 0.01) and could be used to differentiate these species. The taxonomic and biological significance of these differences is discussed.