980 resultados para Missing values structures
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The present work involves the use of p-tert-butylcalix[4,6,8]arene carboxylic acid derivatives ((t)Butyl[4,6,8]CH2COOH) for selective extraction of hemoglobin. All three calixarenes extracted hemoglobin into the organic phase, exhibiting extraction parameters higher than 0.90. Evaluation of the solvent accessible positively charged amino acid side chains of hemoglobin (PDB entry 1XZ2) revealed that there are 8 arginine, 44 lysine and 30 histidine residues on the protein surface which may be involved in the interactions with the calixarene molecules. The hemoglobin-(t)Butyl[6]CH2COOH complex had pseudoperoxidase activity which catalysed the oxidation of syringaldazine in the presence of hydrogen peroxide in organic medium containing chloroform. The effect of pH, protein and substrate concentrations on biocatalysis was investigated using the hemoglobin-(t)Butyl[6]CH2COOH complex. This complex exhibited the highest specific activity of 9.92 x 10(-2) U mg protein(-1) at an initial pH of 7.5 in organic medium. Apparent kinetic parameters (V'(max), K'(m), k'(cat) and k'(cat)/K'(m)) for the pseudoperoxidase activity were determined in organic media for different pH values from a Michaelis-Menten plot. Furthermore, the stability of the protein-calixarene complex was investigated for different initial pH values and half-life (t(1/2)) values were obtained in the range of 1.96 and 2.64 days. Hemoglobin-calixarene complex present in organic medium was recovered in fresh aqueous solutions at alkaline pH, with a recovery of pseudoperoxidase activity of over 100%. These results strongly suggest that the use of calixarene derivatives is an alternative technique for protein extraction and solubilisation in organic media for biocatalysis.
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O presente trabalho foi realizado no âmbito do Trabalho Final de Mestrado em Engenharia Civil do Instituto Superior de Engenharia de Lisboa. O trabalho consistiu em realizar um Projecto de Execução de uma Passagem Superior com três tramos em Betão Armado e Pré-Esforçado. Foram tidos em conta os condicionamentos da topografia local, geotécnica e de traçado. O dimensionamento dos elementos estruturais foi efectuado de acordo com a regulamentação portuguesa actualmente em vigor, nomeadamente o Regulamento de Segurança e Acções (RSA) e o Regulamento de Estruturas de Betão Armado e Pré-esforçado (REBAP). A verificação da segurança foi efectuada em relação aos Estados Limites Últimos e de Utilização. Para a análise estrutural foi utilizado o programa de cálculo automático SAP2000.
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Mestrado em Radiações Aplicadas às Tecnologias da Saúde.
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Eastwards / Westwards: Which Direction for Gender Studies in the XXIst Century? is a collection of essays which focus on themes and methods that characterize current research into gender in Asian countries in general. In this collection, ideas derived from Gender Studies elsewhere in the world have been subjected to scrutiny for their utility in helping to describe and understand regional phenomena. But the concepts of Local and Global – with their discoursive productions – have not functioned as a binary opposition: localism and globalism are mutually constitutive and researchers have interrogated those spaces of interaction between the ‘self’ and the ‘other’, bearing in mind their own embeddedness in social and cultural structures and their own historical memory. Contributors to this collection provided a critical transnational perspective on some of the complex effects of the dynamics of cultural globalization, by exploring the relation between gender and development, language, historiography, education and culture. We have also given attention to the ideological and rhetorical processes through which gender identity is constructed, by comparing textual grids and patterns of expectation. Likewise, we have discussed the role of ethnography, anthropology, historiography, sociology, fiction, popular culture and colonial and post-colonial sources in (re)inventing old/new male/female identities, their conversion into concepts and circulation through time and space. This multicultural and trans-disciplinary selection of essays is totally written in English, fully edited and revised, therefore, it has a good potential for an immediate international circulation. This project may trace new paths and issues for discussion on what concerns the life, practices and narratives by and about women in Asia, as well as elsewhere in the present day global experience. Academic readership: Researchers, scholars, educators, graduate and post-graduate students, doctoral students and general non-fiction readers, with a special interest in Gender Studies, Asia, Colonial and Post-Colonial Literature, Anthropology, Cultural Studies, History, Historiography, Politics, Race, Feminism, Language, Linguistics, Power, Political and Feminist Agendas, Popular Culture, Education, Women’s Writing, Religion, Multiculturalism, Globalisation, Migration. Chapter summary: 1. “Social Gender Stereotypes and their Implication in Hindi”, Anjali Pande, Jawaharlal Nehru University, New Delhi, India. This essay looks at the subtle ways in which gender identities are constructed and reinforced in India through social norms of language use. Language itself becomes a medium for perpetuating gender stereotypes, forcing its speakers to confirm to socially defined gender roles. Using examples from a classroom discussion about a film, this essay will highlight the underlying rigid male-female stereotypes in Indian society with their more obvious expressions in language. For the urban woman in India globalisation meant increased economic equality and exposure to changed lifestyles. On an individual level it also meant redefining gender relations and changing the hierarchy in man-woman relationships. With the economic independence there is a heightened sense of liberation in all spheres of social life, a confidence to fuzz the rigid boundaries of gender roles. With the new films and media celebrating this liberated woman, who is ready to assert her sexual needs, who is ready to explode those long held notions of morality, one would expect that the changes are not just superficial. But as it soon became obvious in the course of a classroom discussion about relationships and stereotypes related to age, the surface changes can not become part of the common vocabulary, for the obvious reason that there is still a vast gap between the screen image of this new woman and the ground reality. Social considerations define the limits of this assertiveness of women, whereas men are happy to be liberal within the larger frame of social sanctions. The educated urban woman in India speaks in favour of change and the educated urban male supports her, but one just needs to scratch the surface to see the time tested formulae of gender roles firmly in place. The way the urban woman happily balances this emerging promise of independence with her gendered social identity, makes it necessary to rethink some aspects of looking at gender in a gradually changing, traditional society like India. 2. “The Linguistic Dimension of Gender Equality”, Alissa Tolstokorova, Kiev Centre for Gender Information and Education, Ukraine. The subject-matter of this essay is gender justice in language which, as I argue, may be achieved through the development of a gender-related approach to linguistic human rights. The last decades of the 20th century, globally marked by a “gender shift” in attitudes to language policy, gave impetus to the social movement for promoting linguistic gender equality. It was initiated in Western Europe and nowadays is moving eastwards, as ideas of gender democracy progress into developing countries. But, while in western societies gender discrimination through language, or linguistic sexism, was an issue of concern for over three decades, in developing countries efforts to promote gender justice in language are only in their infancy. My argument is that to promote gender justice in language internationally it is necessary to acknowledge the rights of women and men to equal representation of their gender in language and speech and, therefore, raise a question of linguistic rights of the sexes. My understanding is that the adoption of the Universal Declaration of Linguistic Rights in 1996 provided this opportunity to address the problem of gender justice in language as a human rights issue, specifically as a gender dimension of linguistic human rights. 3. “The Rebirth of an Old Language: Issues of Gender Equality in Kazakhstan”, Maria Helena Guimarães, Polytechnic Institute of Porto, Portugal. The existing language situation in Kazakhstan, while peaceful, is not without some tension. We propose to analyze here some questions we consider relevant in the frame of cultural globalization and gender equality, such as: free from Russian imperialism, could Kazakhstan become an easy prey of Turkey’s “imperialist dream”? Could these traditionally Muslim people be soon facing the end of religious tolerance and gender equality, becoming this new old language an easy instrument for the infiltration in the country of fundamentalism (it has already crossed the boarders of Uzbekistan), leading to a gradual deterioration of its rich multicultural relations? The present structure of the language is still very fragile: there are three main dialects and many academics defend the re-introduction of the Latin alphabet, thus enlarging the possibility of cultural “contamination” by making the transmission of fundamentalist ideas still easier through neighbour countries like Azerbaijan, Uzbekistan and Turkmenistan (their languages belong to the same sub-group of Common Turkic), where the Latin alphabet is already in use, and where the ground for such ideas shown itself very fruitful. 4. “Construction of Womanhood in the Bengali Language of Bangladesh”, Raasheed Mahmood; University of New South Wales, Sydney. The present essay attempts to explore the role of gender-based language differences and of certain markers that reveal the status accorded to women in Bangladesh. Discrimination against women, in its various forms, is endemic in communities and countries around the world, cutting across class, race, age, and religious and national boundaries. One cannot understand the problems of gender discrimination solely by referring to the relationship of power or authority between men and women. Rather one needs to consider the problem by relating it to the specific social formation in which the image of masculinity and femininity is constructed and reconstructed. Following such line of reasoning this essay will examine the nature of gender bias in the Bengali language of Bangladesh, holding the conviction that as a product of social reality language reflects the socio-cultural behaviour of the community who speaks it. This essay will also attempt to shed some light on the processes through which gender based language differences produce actual consequences for women, who become exposed to low self-esteem, depression and systematic exclusion from public discourse. 5. “Marriage in China as an expression of a changing society”, Elisabetta Rosado David, University of Porto, Portugal, and Università Ca’Foscari, Venezia, Italy. In 29 April 2001, the new Marriage Law was promulgated in China. The first law on marriage was proclaimed in 1950 with the objective of freeing women from the feudal matrimonial system. With the second law, in 1981, values and conditions that had been distorted by the Cultural Revolution were recovered. Twenty years later, a new reform was started, intending to update marriage in the view of the social and cultural changes that occurred with Deng Xiaoping’s “open policy”. But the legal reform is only the starting point for this case-study. The rituals that are followed in the wedding ceremony are often hard to understand and very difficult to standardize, especially because China is a vast country, densely populated and characterized by several ethnic minorities. Two key words emerge from this issue: syncretism and continuity. On this basis, we can understand tradition in a better way, and analyse whether or not marriage, as every social manifestation, has evolved in harmony with Chinese culture. 6. “The Other Woman in the Portuguese Colonial Empire: The Case of Portuguese India”, Maria de Deus Manso, University of Évora, Portugal. This essay researches the social, cultural and symbolic history of local women in the Portuguese Indian colonial enclaves. The normative Portuguese overseas history has not paid any attention to the “indigenous” female populations in colonial Portuguese territories, albeit the large social importance of these social segments largely used in matrimonial and even catholic missionary strategies. The first attempt to open fresh windows in the history of this new field was the publication of Charles Boxer’s referential study about Women in lberian Overseas Expansion, edited in Portugal only after the Revolution of 1975. After this research we can only quote some other fragmentary efforts. In fact, research about the social, cultural, religious, political and symbolic situation of women in the Portuguese colonial territories, from the XVI to the XX century, is still a minor historiographic field. In this essay we discuss this problem and we study colonial representations of women in the Portuguese Indian enclaves, mainly in the territory of Goa, using case studies methodologies. 7. “Heading East this Time: Critical Readings on Gender in Southeast Asia”, Clara Sarmento, Polytechnic Institute of Porto, Portugal. This essay intends to discuss some critical readings of fictional and theoretical texts on gender condition in Southeast Asian countries. Nowadays, many texts about women in Southeast Asia apply concepts of power in unusual areas. Traditional forms of gender hegemony have been replaced by other powerful, if somewhat more covert, forms. We will discuss some universal values concerning conventional female roles as well as the strategies used to recognize women in political fields traditionally characterized by male dominance. Female empowerment will mean different things at different times in history, as a result of culture, local geography and individual circumstances. Empowerment needs to be perceived as an individual attitude, but it also has to be facilitated at the macrolevel by society and the State. Gender is very much at the heart of all these dynamics, strongly related to specificities of historical, cultural, ethnic and class situatedness, requiring an interdisciplinary transnational approach.
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Characteristics of tunable wavelength filters based on a-SiC:H multi-layered stacked cells are studied both theoretically and experimentally. Results show that the light-activated photonic device combines the demultiplexing operation with the simultaneous photodetection and self amplification of an optical signal. The sensor is a bias wavelength current-controlled device that make use of changes in the wavelength of the background to control the power delivered to the load, acting a photonic active filter. Its gain depends on the background wavelength that controls the electrical field profile across the device.
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Characteristics of tunable wavelength pi'n/pin filters based on a-SiC:H multilayered stacked cells are studied both experimental and theoretically. Results show that the device combines the demultiplexing operation with the simultaneous photodetection and self amplification of the signal. An algorithm to decode the multiplex signal is established. A capacitive active band-pass filter model is presented and supported by an electrical simulation of the state variable filter circuit. Experimental and simulated results show that the device acts as a state variable filter. It combines the properties of active high-pass and low-pass filter sections into a capacitive active band-pass filter using a changing photo capacitance to control the power delivered to the load.
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OBJECTIVE: To establish reference values for hippuric acid (HA) excreted in the urine, and to evaluate the impact of age, gender, alcohol, and tobacco, on these levels in a population nonexposed to toluene. METHODS: Reference values for hippuric acid in urine were determined in 115 toluene nonexposed healthy volunteers, from Alfenas city, Southeastern Brazil. A questionnaire was applied to each volunteer and data on occupational and personal habits were collected. Biochemical and hematological analyses were used to confirm the volunteers' good health condition. Reference values were expressed in g HA/g urine creatinine, as mean ± standard deviation (x ± SD), median, 95% confidence interval (95%CI), 95th percentile, and upper reference value (URV, mean +2 SD). RESULTS: Reference values of hippuric acid in urine were: mean ± standard deviation =0.18±0.10; median =0.15; 95% confidence interval =0.16±0.20; 95th percentile = 0.36 and upper reference value (URV, mean +2 SD) =0.38. Statistically significant differences in urinary HA (Wilcoxon - Mann/Whitney, p<0.05) were observed for different genders and age groups. Alcohol ingestion and smoking habit did not significantly affect the results. CONCLUSIONS: The reference values of hippuric acid in urine can be used in biomonitoring programs of workers occupationally exposed to toluene, especially in the southern region of the state of Minas Gerais. Age and gender may affect the HA reference values.
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OBJECTIVE: To evaluate the discriminative and diagnostic values of neuropsychological tests for identifying schizophrenia patients. METHODS: A cross-sectional study with 36 male schizophrenia outpatients and 72 healthy matched volunteers was carried out. Participants underwent the following neuropsychological tests: Wisconsin Card Sorting test, Verbal Fluency, Stroop test, Mini Mental State Examination, and Spatial Recognition Span. Sensitivity and specificity estimated the diagnostic value of tests with cutoffs obtained using Receiver Operating Characteristic curves. The latent class model (diagnosis of schizophrenia) was used as gold standard. RESULTS: Although patients presented lower scores in most tests, the highest canonical function for the discriminant analysis was 0.57 (Verbal Fluency M). The best sensitivity and specificity were obtained in the Verbal Fluency M test (75 and 65, respectively). CONCLUSIONS: The neuropsychological tests showed moderate diagnostic value for the identification of schizophrenia patients. These findings suggested that the cognitive impairment measured by these tests might not be homogeneous among schizophrenia patients.
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Novel [Ru(eta(6)-p-cymene)(kappa(2)-L)X] and [Ru(eta(6)-p-cymene)(kappa(3)-L)]X center dot nH(2)O complexes (L = bis-, tris-, or tetrakis-pyrazolylborate; X = Cl, N-3, PF6, or CF3SO3) are prepared by treatment of [Ru(eta(6)-p-cymene)Cl-2](2) with poly-(pyrazolyl)borate derivatives [M(L)] (L in general; in detail L = Ph(2)Bp = diphenylbis-(pyrazol-1-yl)borate; L = Tp = hydrotris(pyrazol-1-yl)borate; L = pzTp = tetrakis(pyrazol-1-yl)borate; L = Tp(4Bo) = hydrotris(indazol-1-yl)borate, L = T-p4Bo,T-5Me = (5-methylindazol-1-yl)borate; L = Tp(Bn,4Ph) = hydrotris(3-benzyl-4-phenylpyrazol-1-yl)borate; M = Na, K, or TI) and characterized by analytical and spectral data (IR, ESIMS, H-1 and C-13 NMR). The structures of [Ru(eta(6)-p-cymene)(Ph(2)Bp)Cl] (1) and [Ru(eta(6)-p-cymene)(Tp)Cl] (3) have been established by single-crystal X-ray diffraction analysis. Electrochemical studies allowed comparing the electron-donor characters of Tp and related ligands and estimating the corresponding values of the Lever E-L ligand parameter. The complexes [Ru(eta(6)-p-cymene)-(kappa(2)-L)X] and [Ru(eta(6)-p-cymene)(kappa(3)-L)]X center dot nH(2)O act as catalyst precursors for the diastereoselective nitroaldol reaction of benzaldehyde and nitroethane to the corresponding beta-nitroalkanol (up to 82% yield, at room temperature) with diastereoselectivity toward the formation of the threo isomer.
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Four ruthenium(II) complexes with the formula [Ru(eta(5)-C(5)H(5))(PP)L][CF(3)SO(3)], being (PP = two triphenylphosphine molecules), L = 1-benzylimidazole, 1; (PP = two triphenylphosphine molecules), L = 2,2'bipyridine, 2; (PP = two triphenylphosphine molecules), L = 4-Methylpyridine, 3; (PP = 1,2-bis(diphenylphosphine) ethane), L = 4-Methylpyridine, 4, were prepared, in view to evaluate their potentialities as antitumor agents. The compounds were completely characterized by NMR spectroscopy and their crystal and molecular structures were determined by X-ray diffraction. Electrochemical studies were carried out giving for all the compounds quasi-reversible processes. The images obtained by atomic force microscopy (AFM) suggest interaction with pBR322 plasmid DNA. Measurements of the viscosity of solutions of free DNA and DNA incubated with different concentrations of the compounds confirmed this interaction. The cytotoxicity of compounds 1234 was much higher than that of cisplatin against human leukemia cancer cells (HL-60 cells). IC(50) values for all the compounds are in the range of submicromolar amounts. Apoptotic death percentage was also studied resulting similar than that of cisplatin. (C) 2010 Elsevier Inc. All rights reserved.
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Novel [Ru(L)(Tpms)]Cl and [Ru(L)(Tpms(Ph))]Cl complexes (L = p-cymene, benzene, or hexamethylbenzene, Tpms = tris(pyrazolyl)-methanesulfonate, Tpms(Ph) = tris(3-phenylpyrazoly)methanesulfonate) have been prepared by reaction of [Ru(L)(mu-Cl)(2)](2) with Li[Tpms] and Li[Tpms(Ph)], respectively. [Ru(p-cymene)(Tpms)]BF4 has been synthesized through a metathetic reaction of [Ru(p-cymene)(Tpms)]Cl with AgBF4. [RuCl(cod)(Tpms)] (cod = 1,5-cyclooctadiene) and [RuCl(cod)(Tpms(Ph))] are also reported, being obtained by reaction of [RuCl2(cod)(MeCN)(2)] with Li[Tpms] and Li[Tpms(Ph)], respectively. The structures of the complexes and the coordination modes of the ligands have been established by IR, NMR, and single-crystal X-ray diffraction (for [RuL(Tpms)]X (L = p-cymene or HMB, X = Cl; L = p-cymene, X = BF4)) studies. Electrochemical studies showed that each complex undergoes a single-electron R-II -> R-III oxidation at a potential measured by cyclic voltammetry, allowing to compare the electron-donor characters of the tris(pyrazolyl)methanesulfonate and arene ligands, and to estimate, for the first time, the values of the Lever E-L ligand parameter for Tmps(Ph), HMB, and cod.
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This paper, reports experimental work on the use of new heterogeneous solid basic catalysts for biodiesel production: double oxides of Mg and Al, produced by calcination, at high temperature, of MgAl lamellar structures, the hydrotalcites (HT). The most suitable catalyst system studied are hydrotalcite Mg:Al 2:1 calcinated at 507 degrees C and 700 degrees C, leading to higher values of FAME also in the second reaction stage. One of the prepared catalysts resulted in 97.1% Fatty acids methyl esters (FAME) in the 1st reaction step, 92.2% FAME in the 2nd reaction step and 34% FAME in the 3rd reaction step. The biodiesel obtained in the transesterification reaction showed composition and quality parameters within the limits specified by the European Standard EN 14214. 2.5% wt catalyst/oil and a molar ratio methanol:oil of 9:1 or 12:1 at 60 -65 degrees C and 4 h of reaction time are the best operating conditions achieved in this study. This study showed the potential of Mg/Al hydrotalcites as heterogeneous catalysts for biodiesel production. (C) 2011 Elsevier Ltd. All rights reserved.
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The organotin(IV) compounds [Me2Sn(L)(2)] (1), [Et(2)sn(L)(2)] (2), [(Bu2Sn)-Bu-n(L)(2)] (3), [(n)Oct(2)Sn(L)(2)] (4), [Ph2Sn(L)(2)] (5), and [PhOSnL](6) (6) have been synthesized from the reactions of 1-(4-chlorophenyl)-1-cyclopentanecarboxylic acid (HL) with the corresponding diorganotin(IV) oxide or dichloride. They were characterized by IR and multinuclear NMR spectroscopies, elemental analysis, cyclic voltammetry, and, for 2, 3, 4 and 6, single crystal X-ray diffraction analysis. While 1-5 are mononuclear diorganotin (IV) compounds, the X-ray diffraction of 6 discloses a hexameric drumlike structure with a prismatic Sn6O6 core. All these complexes undergo irreversible reductions and were screened for their in vitro antitumor activities toward HL-60, BGC-823, Bel-7402, and KB human cancer cell lines. Within the mononuclear compounds, the most active ones (3, 5) are easiest to reduce (least cathodic reduction potentials), while the least active ones (1, 4) are the most difficult to reduce. Structural rearrangements (i.e., Sn-O bond cleavages and trans-to-cis isomerization) induced by reduction, which eventually can favor the bioactivity, are disclosed by theoretical/electrochemical studies.
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Tendo em conta o aumento do número de estruturas de apoio à primeira infância, particularmente, a expansão da creche, a investigação tem-se debruçado sobre as questões da qualidade. A generalidade dos estudos centra-se na discriminação das dimensões de qualidade e o seu impacto no desenvolvimento das crianças. Contudo, raramente a representação dos pais tem sido alvo de estudo. Partindo do pressuposto que a discussão sobre a qualidade da creche deve ser baseado na evidência empírica mas é, também, um conceito social baseado nos valores e representações dos seus atores, fomos ouvir os pais. Assim, quisemos conhecer: Como escolhiam a creche do seu filho(a)? Qual o seu conceito de qualidade? Que valor atribuem às experiências vividas pelo seus filhos ou filhas na creche? Que representação têm do papel do profissional de educação? Para o efeito, planificámos uma investigação em duas fases correspondendo a dois estudos empíricos. O primeiro estudo tinha como objetivo aferir livremente as Representações dos Pais acerca da Creche numa abordagem qualitativa, com recurso a entrevistas. Das entrevistas procurámos conhecer a opinião de um pequeno grupo de 20 pais com objetivo de aferir indicadores para a construção de um questionário que daria lugar ao segundo estudo - quantitativo. O primeiro estudo daria-nos a noção da opinião e o segundo estudo a noção da sua representação numa amostra de 180 participantes. Tanto quanto conhecemos (pesquisando as bases nacionais) estudos desta natureza sobre as representação dos pais sobre a creche, ainda, não tinham sido realizados em Portugal. De modo geral, os dois estudos revelaram que os pais valorizam a creche como espaço de promoção do desenvolvimento da criança; valorizam a dimensão afetiva do trabalho em creche; as educadoras como profissionais qualificados de educação e o desejo de uma relação estreita, aberta e respeitosa entre a creche e a família. Estes resultados abrem caminho para uma reflexão mais aprofundada acerca das representações, convicções e valores da família em relação à creche. - ABSTRACT Associated with an increased number of support structures for early childhood, we have witnessed a growing interest in studying the quality of these listed structures due to the impact that this will have on the quality development of children. Parents, as primary educators and educational agents privileged child, assume a key role in this regard. Through this study is to evaluate which representations and concept of parents about the quality of daycare. We performed a literature search in order to fit theoretically the main concepts covered in this study. We analyzed investigations already carried out on Nursery and Regulations and Guidelines for National Nursery. In terms of empirical studies we conducted two studies on the Representations about the Parent Nursery: A Qualitative Analysis using interviews with 20 parents and a Quantitative Study applying questionnaires to 180 parents. The main results of both studies revealed that parents value the nursery as a space to promote child development; value the affective dimension of work in nursery; qualified educators and desire for a good and respectful relationship between nursery and the family. These results pave the way for a deeper reflection about the representations, beliefs and values from the family about nursery.
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