931 resultados para Nature of the science
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Within steroid receptor heterocomplexes the large tetraticopeptide repeat-containing immunophilins, cyclophilin 40 (CyP40), FKBP51, and FKBP52, target a common interaction site in heat shock protein 90 (HspSO) and act coordinately with HspSO to modulate receptor activity. The reversible nature of the interaction between the immunophilins and HspSO suggests that relative cellular abundance might be a key determinant of the immunophilin component within steroid receptor complexes. To investigate CyP40 gene regulation, we have isolated a fi-kilobase (kb) 5 ' -flanking region of the human gene and demonstrated that a similar to 50 base pair (bp) sequence adjacent to the transcription start site is essential for CyP40 basal expression. Three tandemly arranged Ets sites within this critical region were identified as binding elements for the multimeric Ets-related transcription factor, GA binding protein (GABP). Functional studies of this proximal promoter sequence, in combination with mutational analysis, confirmed these sites to be crucial for basal promoter function. Furthermore, overexpression of both GABP alpha and GABP beta subunits in Cos1 cells resulted in increased endogenous CyP40 mRNA levels. Significantly, a parallel increase in FKBP52 mRNA expression was not observed, highlighting an important difference in the mode of regulation of the CyP40 and FKBP52 genes. Our results identify GABP as a key regulator of CyP40 expression. GAFF is a common target of mitogen and stress-activated pathways and may integrate these diverse extracellular signals to regulate CyP40 gene expression.
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The general objective of this work was to study the contribution of the ERP for the quality of the managerial accounting information, through the perception of managers of large sized Brazilian companies. The initial principle was that, presently, we live in an enterprise reality characterized by global and competitive worldwide scenery where the information about the enterprise performance and the evaluation of the intangible assets are necessary conditions for the survival, of the companies. The research of the exploratory type is based on a sample of 37 managers of large sized-Brazilian companies. The analysis of the data treated by means of the qualitative method showed that the great majority of the companies of the sample (86%) possess an ERP implanted. It also showed that this system is used in combination with other applicative software. The managers, in its majority, were also satisfied with the information generated in relation to the dimensions Time and Content. However, with regard to the qualitative nature of the information, the ERP made some analysis possible when the Balanced Scorecard was adopted, but information able to provide an estimate of the investments carried through in the intangible assets was not obtained. These results Suggest that in these companies ERP systems are not adequate to support strategic decisions.
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The objective of the present study was to assess the influence of decortication of the posterior elements of the vertebra (recipient bed) and the nature of the bone graft (cortical or cancellous bone) on graft integration and bone, cartilage and fiber neoformation in the interface between the vertebral recipient bed and the bone graft. Seventy-two male Wistar rats were divided into four experimental groups according to the presence or absence of decortication of the posterior vertebral elements and the use of a cortical or cancellous bone graft. Group I-the posterior elements were decorticated and cancellous bone used. Group II-the posterior elements were decorticated and cortical graft was used. Group III-the posterior elements were not decorticated and cancellous graft was used. Group IV-the posterior elements were not decorticated and cortical graft was used. The animals were killed 3, 6 and 9 weeks after surgery and the interface between the posterior elements and the bone graft was subjected to histomorphometric evaluation. Mean percent neoformed bone was 40.8% in group I (decortication and cancellous graft), 39.13% in group II (decortication and cortical graft), 6.13% in group III (non-decorticated and cancellous graft), and 9.27% in group IV (non-decorticated and cortical graft) for animals killed at 3 weeks (P = 0.0005). For animals killed at 6 weeks, the mean percent was 38.53% for group I, 40.40% for group II, 10.27% for group III, and 7.6% for group IV (P = 0.0005), and for animals killed at 9 weeks, the mean was 25.93% for group I, 30.6% for group II, 16.4% for group III, and 18.73% for group IV (P = 0.0026). The mean percent neoformed cartilage tissue was 8.36% for group I, 7.46% for group II, 11.1% for group III, and 9.13% for group IV for the animals killed at 3 weeks (P = 0.6544); 6.6% for group I, 8.07% for group, 7.47% for group III and 6.13% for group IV (P = 0.4889) for animals killed at 6 weeks, and 3.13% for group I, 4.06% for group II, 10.53% for group III and 12.07% for group IV (P = 0.0006) for animals killed at 9 weeks. Mean percent neoformed fibrous tissue was 11% for group I, 6.13% for group II, 26.27% for group III and 21.87% for group IV for animals killed at 3 weeks (P = 0.0008); 7.67% for group I, 7.1% for group II, 9.8% for group III and 10.4% for group IV (P = 0.7880) for animals killed at 6 weeks, and 3.73% for group I, 4.4% for group II, 6.67% for group III and 6.8% for group IV (P = 0.0214) for animals killed at 9 weeks. The statistically significant differences in percent tissue formation were related to decortication of the posterior elements. The use of a cortical or cancellous graft did not influence tissue neoformation. Ossification in the interface of the recipient graft bed was of the intramembranous type in the decorticated animals and endochondral type in the non-decorticated animals.
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Flying foxes are commonly thought of as highly social mammals, yet little is known about the dynamics of their social interactions at a day roost. The aim of the present study was to examine the nature of the seasonal activities of territoriality and courtship amongst wild flying foxes in Australia. Focal observations were conducted at two permanent roosts of black flying foxes Pteropus alecto during periods of peak social interaction in the summers of 1999 and 2000 in urban Brisbane, Queensland. Observations of male territoriality were conducted at dawn and began eight weeks prior to the commencement of mating. The majority of defense bouts (87%) consisted of ritualised pursuit, while 13% of bouts involved physical contact expressed as either wrestling or hooking. One male with an unusually large territory took significantly longer to defend it than other males with less territory to defend. Observations of courtship revealed repetitive courtship sequences, including pre-copulatory approaches by the males, copulation attempts and grooming/resting periods. Thirty-four complete courtship sequences incorporating 135 copulation attempts were recorded over two seasons. Females actively resisted courtship approaches by males, forcing males to display a continuous determination to mate over time where determination can be considered an indicator of 'fitness'. The courtship bout length of females with suckling young was significantly longer ((x) over bar +/- SE; 230.9 +/- 22.16 s) than that of females unencumbered by large pups (158.5 +/- 9.69 s), although the length of copulations within those courtships was not (45.6 +/- 5.19 versus 36.2 +/- 3.43 s).
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We investigate spectral functions extracted using the maximum entropy method from correlators measured in lattice simulations of the (2+1)-dimensional four-fermion model. This model is particularly interesting because it has both a chirally broken phase with a rich spectrum of mesonic bound states and a symmetric phase where there are only resonances. In the broken phase we study the elementary fermion, pion, sigma, and massive pseudoscalar meson; our results confirm the Goldstone nature of the π and permit an estimate of the meson binding energy. We have, however, seen no signal of σ→ππ decay as the chiral limit is approached. In the symmetric phase we observe a resonance of nonzero width in qualitative agreement with analytic expectations; in addition the ultraviolet behavior of the spectral functions is consistent with the large nonperturbative anomalous dimension for fermion composite operators expected in this model.
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The acidic properties of hexagonal mesoporous aluminosilicates synthesized via a new successful short time synthesis route using leached saponite and a low concentration of surfactant are thoroughly investigated. The resulting aluminosilicate mesoporous materials with high Si/Al ratios of around 11 have a maximal surface area of 1130 m(2)/g, a pore volume of 0.92 cm(3)/g, and a narrow pore size distribution at around 3 nm. The replacement of the sodium ions, present as counterions in the synthesized aluminosilicates, with protons imparts useful catalytic acidity. This acidity is extensively studied with FTIR spectroscopy after adsorption of ammonia and cyclohexylamine, while deuterated acetonitrile differentiates between Bronsted and Lewis acidity. Al-27 NMR spectroscopy determined the coordination of the aluminum in the FSM materials. Simultaneously the effect of an additional Al incorporation, utilizing sodium aluminate, aluminum nitrate, and aluminum isopropoxide is studied. From an acidic point of view, the incorporation with Al(NO3)(3) appears to be the most optimal, as the sample has a very high amount of acid sites (1.3 mmol/g). Investigating the nature of the acid sites it is found that in all samples except the one incorporated with Al(NO3)(3), more Bronsted than Lewis sites are present, both sites being quite acidic as they resist desorption temperatures up to 300 degreesC. Probing the coordination and location of the Al atoms, all the catalysts appeared to have mostly tetrahedral aluminum, up to 95% of the total Al amount for the proton exchanged AI(NO3)(3) incorporated sample.
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The present study, covering students from public schools and a private school on the island of São Miguel (Azores, Portugal), aims to meet the difficulties of the students of the 3rd and 4th years of the primary education in solving tasks involving construction, reading and interpreting tables and statistical graphs, in the context of Organization and Data Handling (ODH). We present the main results obtained from statistical methods, among which we highlight some non-parametric hypothesis tests and the Categorical Principal Component Analysis (CatPCA), given the nature of the variables included in the questionnaire (mostly nominal and ordinal variables).
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Eukaryotic Cell, Vol.7, Nº6
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The structure and nature of the crust underlying the Santos Basin-São Paulo Plateau System (SSPS), in the SE Brazilian margin, are discussed based on five wide-angle seismic profiles acquired during the Santos Basin (SanBa) experiment in 2011. Velocity models allow us to precisely divide the SSPS in six domains from unthinned continental crust (Domain CC) to normal oceanic crust (Domain OC). A seventh domain (Domain D), a triangular shape region in the SE of the SSPS, is discussed by Klingelhoefer et al. (2014). Beneath the continental shelf, a similar to 100km wide necking zone (Domain N) is imaged where the continental crust thins abruptly from similar to 40km to less than 15km. Toward the ocean, most of the SSPS (Domains A and C) shows velocity ranges, velocity gradients, and a Moho interface characteristic of the thinned continental crust. The central domain (Domain B) has, however, a very heterogeneous structure. While its southwestern part still exhibits extremely thinned (7km) continental crust, its northeastern part depicts a 2-4km thick upper layer (6.0-6.5km/s) overlying an anomalous velocity layer (7.0-7.8km/s) and no evidence of a Moho interface. This structure is interpreted as atypical oceanic crust, exhumed lower crust, or upper continental crust intruded by mafic material, overlying either altered mantle in the first two cases or intruded lower continental crust in the last case. The deep structure and v-shaped segmentation of the SSPS confirm that an initial episode of rifting occurred there obliquely to the general opening direction of the South Atlantic Central Segment.
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BACKGROUND: Bladder cancer is a significant health problem in rural areas of Africa and the Middle East where Schistosoma haematobium is prevalent, supporting an association between malignant transformation and infection by this blood fluke. Nevertheless, the molecular mechanisms linking these events are poorly understood. Bladder cancers in infected populations are generally diagnosed at a late stage since there is a lack of non-invasive diagnostic tools, hence enforcing the need for early carcinogenesis markers. METHODOLOGY/PRINCIPAL FINDINGS: Forty-three formalin-fixed paraffin-embedded bladder biopsies of S. haematobium-infected patients, consisting of bladder tumours, tumour adjacent mucosa and pre-malignant/malignant urothelial lesions, were screened for bladder cancer biomarkers. These included the oncoprotein p53, the tumour proliferation rate (Ki-67>17%), cell-surface cancer-associated glycan sialyl-Tn (sTn) and sialyl-Lewisa/x (sLea/sLex), involved in immune escape and metastasis. Bladder tumours of non-S. haematobium etiology and normal urothelium were used as controls. S. haematobium-associated benign/pre-malignant lesions present alterations in p53 and sLex that were also found in bladder tumors. Similar results were observed in non-S. haematobium associated tumours, irrespectively of their histological nature, denoting some common molecular pathways. In addition, most benign/pre-malignant lesions also expressed sLea. However, proliferative phenotypes were more prevalent in lesions adjacent to bladder tumors while sLea was characteristic of sole benign/pre-malignant lesions, suggesting it may be a biomarker of early carcionogenesis associated with the parasite. A correlation was observed between the frequency of the biomarkers in the tumor and adjacent mucosa, with the exception of Ki-67. Most S. haematobium eggs embedded in the urothelium were also positive for sLea and sLex. Reinforcing the pathologic nature of the studied biomarkers, none was observed in the healthy urothelium. CONCLUSION/SIGNIFICANCE: This preliminary study suggests that p53 and sialylated glycans are surrogate biomarkers of bladder cancerization associated with S. haematobium, highlighting a missing link between infection and cancer development. Eggs of S. haematobium express sLea and sLex antigens in mimicry of human leukocytes glycosylation, which may play a role in the colonization and disease dissemination. These observations may help the early identification of infected patients at a higher risk of developing bladder cancer and guide the future development of non-invasive diagnostic tests.
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Seismic ambient noise tomography is applied to central and southern Mozambique, located in the tip of the East African Rift (EAR). The deployment of MOZART seismic network, with a total of 30 broad-band stations continuously recording for 26 months, allowed us to carry out the first tomographic study of the crust under this region, which until now remained largely unexplored at this scale. From cross-correlations extracted from coherent noise we obtained Rayleigh wave group velocity dispersion curves for the period range 5–40 s. These dispersion relations were inverted to produce group velocity maps, and 1-D shear wave velocity profiles at selected points. High group velocities are observed at all periods on the eastern edge of the Kaapvaal and Zimbabwe cratons, in agreement with the findings of previous studies. Further east, a pronounced slow anomaly is observed in central and southern Mozambique, where the rifting between southern Africa and Antarctica created a passive margin in the Mesozoic, and further rifting is currently happening as a result of the southward propagation of the EAR. In this study, we also addressed the question concerning the nature of the crust (continental versus oceanic) in the Mozambique Coastal Plains (MCP), still in debate. Our data do not support previous suggestions that the MCP are floored by oceanic crust since a shallow Moho could not be detected, and we discuss an alternative explanation for its ocean-like magnetic signature. Our velocity maps suggest that the crystalline basement of the Zimbabwe craton may extend further east well into Mozambique underneath the sediment cover, contrary to what is usually assumed, while further south the Kaapval craton passes into slow rifted crust at the Lebombo monocline as expected. The sharp passage from fast crust to slow crust on the northern part of the study area coincides with the seismically active NNE-SSW Urema rift, while further south the Mazenga graben adopts an N-S direction parallel to the eastern limit of the Kaapvaal craton. We conclude that these two extensional structures herald the southward continuation of the EAR, and infer a structural control of the transition between the two types of crust on the ongoing deformation.
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We report a case of an inflammatory pseudotumor of the urinary bladder in a 31 year-old woman. She presented at the emergency room with low abdominal pain and urinary symptoms. Abdominal ultrasound, computed tomography and magnetic resonance imaging were performed and revealed asymmetric thickening of the urinary bladder wall. Cystoscopy with urinary cytology revealed a benign nature of the process. The patient underwent partial cystectomy and the pathologic examination of the specimen revealed an inflammatory pseudotumor. We reviewed the clinical, imaging and pathological features of the inflammatory pseudotumor of the urinary bladder and discussed its differential diagnosis.
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This dissertation focuses on a rare 15th century commemorative programme that has thus far received little scholarly attention: the collective monument erected in the Founder’s Chapel, at the Monastery of Santa Maria da Vitória, Batalha, to house the remains of four Avis princes, members of what would become known as ‘the Illustrious Generation’. A patron is proposed for the commission of this erudite monument - the princes’ eldest brother, king Duarte I - arguing its integration into a broader propaganda programme to glorify the memory of the Avis dynasty founder, king João I. The dissertation then proceeds to discuss various highly innovative features of the monument, such as its pseudo-architectural character, its use of sophisticated heraldry and personal badges, the apparent absence of religious iconography on the tombs and, importantly, the collective nature of the programme, key to its interpretation. Using a semiotic approach, a discussion is also offered on the way the various formal, iconographic and conceptual novelties of the princes’ monument impacted on the 15th century monumental landscape in Portugal. Finally, the monument and the chapel housing it are looked at through the prism of the various readings that successive generations of viewers have projected onto it, from the time of its creation to the turn of the 20th century, in order to offer a more comprehensive understanding of the object as it stands today.
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Esta propuesta de investigación se enmarca en los encuentros y discusiones que se están realizando en la Escuela de Artes de la Facultad de Filosofía y Humanidades (CEPIA, CIFFyH y SeCyT, de la U.N.C), en relación a las problemáticas de la investigación en Artes. Los encuentros llevados a cabo en diversas ocasiones y a lo largo de 2009, demuestran la necesidad de establecer un campo particular de la investigación y su relación con la práctica artística. Este proyecto nace de estas inquietudes y establece ciertos ejes de trabajo que permiten poner en práctica ciertos esbozos imaginados. En este sentido, nuestra propuesta se centra en definir la misma construcción escénica como objeto de estudio, delimitando sobre éste la problemática de lo real en el trabajo de la ficción, proponiendo además un equipo que permita investigar en su propio desarrollo creativo las diversas variables que entran en juego. De este modo, se trabajará en una propuesta de laboratorio escénico donde los planteos de orden teórico atraviesen la práctica y, a su vez, la observación de ésta permita una reelaboración y profundización del pensamiento contemporáneo sobre la problemática ejecución/representación, desde los diversos órdenes en que ésta interviene. La idea de representación teatral que planteaba Aristóteles señala que las acciones devienen necesariamente en la definición del carácter de los personajes. Este concepto es clave en el desarrollo del teatro occidental y por ende en las diferentes concepciones de actor. La definición de acción dada por Aristóteles es problemática para parte del teatro contemporáneo ya que supone que toda acción es mimética. También da por supuesto que en el teatro se conforman personajes, y que la unidad narrativa está dada por una programática, que es definida por la acción.La presente investigación se propone indagar en la relación entre la ejecución de la acción y su representación en el desarrollo de un laboratorio teatral. Esto implica que necesariamente es aplicada al trabajo escénico. Nuestra hipótesis de partida es que la relación conflictiva entre acción, ejecución de la misma y representación, se produce a partir de la operación material sobre lo real . Estas intersecciones podrían ser pensadas como una teoría del montaje donde la corporalidad es el principio necesario e irreductible de la construcción. La intersección de lo real es una problemática que permite ahondar sobre los procedimientos por los cuales se construye la escena. La idea de un teatro material, obliga a pensar con qué procedimientos se construye ficción. Un teatro que intenta recalar en lo “real” como modo de señalar la cosa misma, se propone, desde la perspectiva de la realización, indagar en los mecanismos de su construcción (procedimientos), por lo cual supone que la actividad teatral puede dar cuenta de los procesos por los cuales se realiza. La realización de una acción, puede remitir a sí misma y genera una relación “extraña” y ambigua con el mundo de referencia. La acción en sí misma, pone en cuestión la idea de modelo y da cuenta de una crisis en la representación. La teoría ha intentado dividir y sistematizar de manera binaria la manifestación teatral: Teatro de Representación/ Teatro Performático, para distinguir un teatro vinculado a la creación de personajes o para relacionarlo a un teatro de ejecución. Sin embargo, pensamos que es posible encontrar en la producción escénica, intersecciones de lo real que median el mundo de la representación y el de la performance para la construcción de ficción. Nuestra hipótesis de base es que si intervenimos el plano de la ejecución en el actor, la representación varía sustancialmente sus mecanismos de producción de sentido. Este primer planteo no es conflictivo hasta que se pone de manifiesto lo real. This research’s proposal is framed into the meetings and discussions that have been taking place in the School of Arts of the Faculty of Philosophy and Humanities (CEPIA, CIFFyH y SeCyT, of the National University of Cordoba), concerning the difficulties of research in Arts. The meetings carried out along 2009, demonstrate the need to establish a particular field of research and its relation to the practice of arts. This project is born from these concerns and it establishes central axis for the work, that enables us to put on practice some sketches imagined. In this regard, our proposal focuses on defining the construction of the scene as object of study, in itself, delimiting the issue of “the real” in the work of fiction. Proposing, furthermore, a team for researching the many variables that comes into play, in their own creative development. Consequently, the work will be developed in the method of a scenic laboratory, where the theoretical proposals cross over the practice and, in turn, these observations allow a reworking and deepen of contemporary thinking about the problematic of performance / representation, from the diverse orders in which it intervene. The idea of theatrical performance proposed by Aristotle, indicate that actions necessarily turn into the definition of the nature of the characters. This concept is key to the development of Western theaterand consequently on the different conceptions of actor. The definition of action given by Aristotle is problematic for a part of the contemporary theater, because it assumes that every action is mimetic. Also presumes that in the theatre the characters are formed, and narrative unit is given by a programmatic, which is defined by the action. This research proposes to explore the relationship between implementation of the action and its representation in the development of a theatrical laboratory. This implies that it is applied necessarily to the scenic practice. Our preliminary hypothesis is that the co.
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Tourism education in Ireland has witnessed a transformation within the last four decades since CERT introduced the first fundamentals of training in the 1960’s. An analysis of the provision of tourism education in Ireland, focusing on the needs of the public, private and voluntary sectors was the main focus of this study and concentrates mainly on third level provision of tourism education within the island of Ireland. The study examines the role of tourism education in Ireland, establishing any current or emerging trends in third level tourism provision. It identifies and analyses the main stakeholders in the public, private and voluntary sectors and investigates if any requirements exist in the provision of third level education. The multi-faceted nature of the tourism industry has resulted in the provision of a diverse range of educational courses. As a result of this diversity, a question hangs over the status of tourism as a professional discipline within itself. Other issues identified through this study are the over provision of tourism courses and the current and future disparity within tourism education. The qualitative nature of the research involved questioning of major stakeholders and educators who influence tourism education provision and developing an overview of the current status of tourism education provision in Ireland identifying the present needs of each sector. Finally several strategies are suggested which may enhance third level tourism education in the future.