Many plants require exposure to low temperature for a certain period during each year. This was determined more than a century ago. Understanding this phenomenon, known as the rest period, is part of a larger problem of understanding the factors which determine the ability of an organism to grow. The property of rest is ultimately a property of the actively growing cells, rather than that of the cells involved with protection and support.

presente pesquisa investiga as representações de conhecimentos químicos e sua relação com a Escola – Básica e Superior. Para tanto, elegemos dois autores como referências teóricas básicas e um conceito químico exaustivamente estudado pelos educadores em química, respectivamente: Gaston Bachelard e Serge Moscovisci e o conceito de Transformações Químicas. Em Gaston Bachelard, buscamos a perspectiva epistemológica sobre ―representação‖, considerando seu trabalho no universo científico – reificado. Em Serge Moscovici investigamos a produtividade de seu conceito de ―representação social‖ para interpelar as dinâmicas do conhecimento científico na Escola. Dessa interação entre os dois entendimentos de ―representação‖ que têm em comum a representação dos conhecimentos em ciência, cunhamos um conceito para uma investigação num universo específico - distante do reificado e do senso comum e correlato a ambos –, o universo escolar. É, então, a partir dessas considerações que esta pesquisa cria inicialmente o conceito das representações escolares e, no seu desenvolvimento, o aplica como ferramenta teórica de análise da constituição de saberes e conhecimentos na Escola investigando as Transformações Químicas. No desenvolvimento do trabalho, ao longo das análises, foram destacadas características das representações escolares, como sua constituição na comunicação entre saberes/conhecimentos de outros universos que buscavam ser recontextualizados ao universo escolar, onde, pautados no conhecimento de referência, se buscavam os conhecimentos preferíveis. Conjuntamente a essa análise, este trabalho destaca a existência de perfis de representações escolares e seu desenvolvimento em diferentes dimensões. Disso, trouxemos as representações escolares como formas de conhecimento inerentes, imanentes e imbricadas à Escola e cujo estudo, que buscaremos aprofundar em pesquisas futuras, tem potencialidades de contribuir com a Escola, a formação inicial e continuada de professores, uma vez que esse conceito/ferramenta teórica nos possibilita discutir seja o modo como os conhecimentos/saberes de outros universos, que não aquele propriamente da Escola, são recontextualizados, modificados, selecionados e incorporados a ela, seja o desenvolvimento de um estudo sobre os efeitos que tais representações têm no processo educacional, escolar. / This research investigates the representations of chemical knowledge and its relationship with the School - Basic and Higher. To this end, we chose two authors as references and a basic theoretical concept thoroughly studied by chemical educators in chemistry, respectively: Gaston Bachelard and Serge Moscovisci and the concept of chemical transformations. In Gaston Bachelard, we seek the epistemological perspective on "representation", considering his work in the scientific world - reified. In Serge Moscovici we investigate the productivity of his concept of "social representation" to question the dynamics of scientific knowledge in school. From this interaction between the two understandings of "representation" that have in common the representation of knowledge in science, a concept is brought to investigate in a specific universe - away from the reified and common sense and correlated to both - the school universe. It is, therefore, from these considerations that this research initially creates the concept of school representations and in their development, applied as a theoretical tool to analyze the constitution of knowledge and expertise in the School investigating the chemical changes. In developing this work over the analysis were highlighted features representations of school, as its constitution in communication between knowledge / skills from other universities who seek to be contextualized to the school, where, guided by the knowledge of reference, if the knowledge sought preferable. Together with this analysis, this paper emphasizes the existence of school representations profiles and their development in different dimensions. In addition, we brought the school representations as forms of knowledge inherent, immanent and intertwined with the School and whose study, which will seek to deepen in future research, has the potential to contribute to the School, the initial and continuing training of teachers, since this concept / theoretical tool enables us to discuss is how the knowledge / knowledge of other universes, other than that the school itself, are recontextualized, modified, selected and incorporated into it, is the development of a study on the effects that these representations are in the process educational school.

Drying with the help of sun and wind is one of the oldest methods of food preservation known to man, but artificial drying, or dehydration, has been developed and used extensively only during the last two decades. The problem in dehydration is that the water content must be decreased sufficiently to maintain the stability of the product by retarding the rates of deteriorative biochemical, microbiological, and enzymatic reactions during subsequent storage. At the same time irreversible changes should not be brought about.

presente pesquisa investiga as representações de conhecimentos químicos e sua relação com a Escola – Básica e Superior. Para tanto, elegemos dois autores como referências teóricas básicas e um conceito químico exaustivamente estudado pelos educadores em química, respectivamente: Gaston Bachelard e Serge Moscovisci e o conceito de Transformações Químicas. Em Gaston Bachelard, buscamos a perspectiva epistemológica sobre ―representação‖, considerando seu trabalho no universo científico – reificado. Em Serge Moscovici investigamos a produtividade de seu conceito de ―representação social‖ para interpelar as dinâmicas do conhecimento científico na Escola. Dessa interação entre os dois entendimentos de ―representação‖ que têm em comum a representação dos conhecimentos em ciência, cunhamos um conceito para uma investigação num universo específico - distante do reificado e do senso comum e correlato a ambos –, o universo escolar. É, então, a partir dessas considerações que esta pesquisa cria inicialmente o conceito das representações escolares e, no seu desenvolvimento, o aplica como ferramenta teórica de análise da constituição de saberes e conhecimentos na Escola investigando as Transformações Químicas. No desenvolvimento do trabalho, ao longo das análises, foram destacadas características das representações escolares, como sua constituição na comunicação entre saberes/conhecimentos de outros universos que buscavam ser recontextualizados ao universo escolar, onde, pautados no conhecimento de referência, se buscavam os conhecimentos preferíveis. Conjuntamente a essa análise, este trabalho destaca a existência de perfis de representações escolares e seu desenvolvimento em diferentes dimensões. Disso, trouxemos as representações escolares como formas de conhecimento inerentes, imanentes e imbricadas à Escola e cujo estudo, que buscaremos aprofundar em pesquisas futuras, tem potencialidades de contribuir com a Escola, a formação inicial e continuada de professores, uma vez que esse conceito/ferramenta teórica nos possibilita discutir seja o modo como os conhecimentos/saberes de outros universos, que não aquele propriamente da Escola, são recontextualizados, modificados, selecionados e incorporados a ela, seja o desenvolvimento de um estudo sobre os efeitos que tais representações têm no processo educacional, escolar. / This research investigates the representations of chemical knowledge and its relationship with the School - Basic and Higher. To this end, we chose two authors as references and a basic theoretical concept thoroughly studied by chemical educators in chemistry, respectively: Gaston Bachelard and Serge Moscovisci and the concept of chemical transformations. In Gaston Bachelard, we seek the epistemological perspective on "representation", considering his work in the scientific world - reified. In Serge Moscovici we investigate the productivity of his concept of "social representation" to question the dynamics of scientific knowledge in school. From this interaction between the two understandings of "representation" that have in common the representation of knowledge in science, a concept is brought to investigate in a specific universe - away from the reified and common sense and correlated to both - the school universe. It is, therefore, from these considerations that this research initially creates the concept of school representations and in their development, applied as a theoretical tool to analyze the constitution of knowledge and expertise in the School investigating the chemical changes. In developing this work over the analysis were highlighted features representations of school, as its constitution in communication between knowledge / skills from other universities who seek to be contextualized to the school, where, guided by the knowledge of reference, if the knowledge sought preferable. Together with this analysis, this paper emphasizes the existence of school representations profiles and their development in different dimensions. In addition, we brought the school representations as forms of knowledge inherent, immanent and intertwined with the School and whose study, which will seek to deepen in future research, has the potential to contribute to the School, the initial and continuing training of teachers, since this concept / theoretical tool enables us to discuss is how the knowledge / knowledge of other universes, other than that the school itself, are recontextualized, modified, selected and incorporated into it, is the development of a study on the effects that these representations are in the process educational school.

presente pesquisa investiga as representações de conhecimentos químicos e sua relação com a Escola – Básica e Superior. Para tanto, elegemos dois autores como referências teóricas básicas e um conceito químico exaustivamente estudado pelos educadores em química, respectivamente: Gaston Bachelard e Serge Moscovisci e o conceito de Transformações Químicas. Em Gaston Bachelard, buscamos a perspectiva epistemológica sobre ―representação‖, considerando seu trabalho no universo científico – reificado. Em Serge Moscovici investigamos a produtividade de seu conceito de ―representação social‖ para interpelar as dinâmicas do conhecimento científico na Escola. Dessa interação entre os dois entendimentos de ―representação‖ que têm em comum a representação dos conhecimentos em ciência, cunhamos um conceito para uma investigação num universo específico - distante do reificado e do senso comum e correlato a ambos –, o universo escolar. É, então, a partir dessas considerações que esta pesquisa cria inicialmente o conceito das representações escolares e, no seu desenvolvimento, o aplica como ferramenta teórica de análise da constituição de saberes e conhecimentos na Escola investigando as Transformações Químicas. No desenvolvimento do trabalho, ao longo das análises, foram destacadas características das representações escolares, como sua constituição na comunicação entre saberes/conhecimentos de outros universos que buscavam ser recontextualizados ao universo escolar, onde, pautados no conhecimento de referência, se buscavam os conhecimentos preferíveis. Conjuntamente a essa análise, este trabalho destaca a existência de perfis de representações escolares e seu desenvolvimento em diferentes dimensões. Disso, trouxemos as representações escolares como formas de conhecimento inerentes, imanentes e imbricadas à Escola e cujo estudo, que buscaremos aprofundar em pesquisas futuras, tem potencialidades de contribuir com a Escola, a formação inicial e continuada de professores, uma vez que esse conceito/ferramenta teórica nos possibilita discutir seja o modo como os conhecimentos/saberes de outros universos, que não aquele propriamente da Escola, são recontextualizados, modificados, selecionados e incorporados a ela, seja o desenvolvimento de um estudo sobre os efeitos que tais representações têm no processo educacional, escolar. / This research investigates the representations of chemical knowledge and its relationship with the School - Basic and Higher. To this end, we chose two authors as references and a basic theoretical concept thoroughly studied by chemical educators in chemistry, respectively: Gaston Bachelard and Serge Moscovisci and the concept of chemical transformations. In Gaston Bachelard, we seek the epistemological perspective on "representation", considering his work in the scientific world - reified. In Serge Moscovici we investigate the productivity of his concept of "social representation" to question the dynamics of scientific knowledge in school. From this interaction between the two understandings of "representation" that have in common the representation of knowledge in science, a concept is brought to investigate in a specific universe - away from the reified and common sense and correlated to both - the school universe. It is, therefore, from these considerations that this research initially creates the concept of school representations and in their development, applied as a theoretical tool to analyze the constitution of knowledge and expertise in the School investigating the chemical changes. In developing this work over the analysis were highlighted features representations of school, as its constitution in communication between knowledge / skills from other universities who seek to be contextualized to the school, where, guided by the knowledge of reference, if the knowledge sought preferable. Together with this analysis, this paper emphasizes the existence of school representations profiles and their development in different dimensions. In addition, we brought the school representations as forms of knowledge inherent, immanent and intertwined with the School and whose study, which will seek to deepen in future research, has the potential to contribute to the School, the initial and continuing training of teachers, since this concept / theoretical tool enables us to discuss is how the knowledge / knowledge of other universes, other than that the school itself, are recontextualized, modified, selected and incorporated into it, is the development of a study on the effects that these representations are in the process educational school.

No description available.

Carrots (Daucus carota L. cv. Royal Chantenay) and sweet corn vi (Zea mays L. cv. Iochief) were grown rm the Utah State University's Greenville farm in 1969 and 1970. The soil was fumigated with Telone (a mixture of 1, 3-dichloropropene and other chlorinated hydrocarbons) at the rates of 10, 20, and 30 gal/acre and Nemagon (1, 2-dibromo-3-chloropropane) at the rates of 1, 2, and 3 gal/acre one week before planting. Samples of uniformly mature carrot roots were taken for the studies of total carotenes, β-carotene, total and reducing sugars, respiration, and ultrastructural changes; and those of sweet corn seeds for the studies of total carotenoids , starch, total sugar, and total nitrogen changes. Compared to the controls, carrots grown on fumigated soil had a significantly higher content of total carotenes, β-carotene, and total sugars, and a lower rate of respiration. The electron microscopic study indicated that the carrots from Telone (30 gal/acre) and Nemagon (3 gal/acre) fumigated soil had larger chromoplasts that contained more globuli and crystals than those of the controls. The soil fumigations with Telone and Nemagon also brought about the increase in total carotenoid content in sweet corn seeds.

The main purpose of this study was to compare the effectiveness of the cooperative learning based on conceptual change conditions and traditionally designed science instruction on 7th grade students&rsquo / understanding of chemical and physical changes and classification of matter concepts and attitudes toward science as a school subject. In this study 102 seventh grade students from four classes of a Science Course instructed by the two teachers from ODT&Uuml / G.V. &Ouml / zel ilk&ouml / gretim Okulu took part. One of the classes of each teacher was randomly assigned as experimental group, which were instructed with cooperative learning based on conceptual change conditions and the other classes were assigned as control group, which were instructed traditionally. This study was conducted during the 2004-2005 fall semester over a period of four weeks. In this study, to examine the effect of the treatment on dependent variables / science achievement related to chemical and physical changes and classification of matter concepts measured with Classification and Changes of Matter Concepts Test, and science attitude scores measured with Attitude Scale Toward Science as a school subject. Science Process Skills Test was used at the beginning of the study to determine students&rsquo / science process skills. ANCOVA and ANOVA were used testing the hypotheses of the study. The results showed that the cooperative learning based on conceptual change conditions group had a significantly higher scores with respect to achievement related to chemical and physical changes and classification of matter concepts than the traditionally designed science instruction group. However, there is no significant difference between the mean scores of cooperative learning based on conceptual change conditions group and traditionally designed science instruction group with respect to attitudes toward science as a school subject. Science process skills were a strong predictor for the achievement related to chemical and physical changes and classification of matter concepts. It may be useful to use the results of this study and instruments and strategies developed for this study for classroom teachers in order to help students to reduce or eliminate their misconceptions.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2017-02-08T10:12:21Z No. of bitstreams: 2 Dissertação - Gustavo de Melo Oliveira Gonçalves - 2016.pdf: 1630959 bytes, checksum: 90d5f7c22407381803a1e520c265c080 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-02-08T10:12:49Z (GMT) No. of bitstreams: 2 Dissertação - Gustavo de Melo Oliveira Gonçalves - 2016.pdf: 1630959 bytes, checksum: 90d5f7c22407381803a1e520c265c080 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-02-08T10:12:49Z (GMT). No. of bitstreams: 2 Dissertação - Gustavo de Melo Oliveira Gonçalves - 2016.pdf: 1630959 bytes, checksum: 90d5f7c22407381803a1e520c265c080 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-07-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In the last years, due to the government effort, especially in the Tocantins State, there have been significante increase on flooded rice production areas. However, there are few studies about nitrogen sources and doses in that region, which could improve the nitrogen efficiency use and provide higher incomes for farmers. This study aimed to determine the effects of different sources and doses of nitrogen in flooded lowland soils in the pH, redox potential and the concentration of ions in the soil solution in order to obtain the economicallyand environmentally best mineral nitrogen source and dose. The samples were collected in the 2014/2015 season at the Embrapa Rice and Beans Experimental Field - Palmital Farm-, in a Dystric Gleysol. The design was a complete randomized blocks, with four replications, two sources of nitrogen (common urea and slow release urea), three nitrogen rates (30, 70, 150 kg ha-1), and a control, without any N application.Soil solution samples were collected weekly, during the flooded period in rice cultivation, BRS Catiana genotype. The pH analysis and Eh (redoxpotential) were immediately read, just after the soil solution sampling, in the field, and thenHCl (2M) acidified,, and immediately frozen for later analysis of the following ions: Ca, Mg, K, Fe, Zn, Mn, MOS, NO3- and NH4+. The sources used did not affect the release of nutrients dynamics to the soil solution. The anaerobic condition caused changes in the Eh and ions solubility in the soil solution. The doses applied changed Ca and MOS concentrations in solution, and the dose of 150 kg ha-1 N showed the highest values for both. / Nos últimos anos, devido incentivos do governo, especialmente no Estado do Tocantins, houve significante aumento em áreas de produção de arroz irrigado. No entanto, existem poucos estudos sobre fontes de nitrogênio e doses naquela região, o que poderia melhorar a eficiência de uso de nitrogênio e proporcionar maiores rendimentos para os produtores rurais. O presente trabalho teve como objetivo determinar os efeitos de diferentes fontes e doses de nitrogênio em solos de várzea inundados no pH, potencial redox e na concentração de íons da solução do solo, visando a obtenção da fonte e dose de fertilizante economicamente viável e ambientalmente sustentável. As amostras foram coletadas na safra 2014/2015 no Campo Experimental da Fazenda Palmital, da Embrapa Arroz e Feijão, em Gleissolo Háplico. O delineamento utilizado foi o de blocos casualizados com quatro repetições, sendo duas fontes de nitrogênio (ureia comum e ureia de liberação lenta), três doses de N aplicadas em cobertura (30, 70, 150 kg ha-1), e a testemunha absoluta, sem aplicação alguma de N. Foram coletadas amostras de solução do solo, semanalmente, durante o período de inundação no cultivo do arroz, cultivar BRS Catiana. As análises de pH e Eh (potencial de oxirredução) foram feitas logo após a coleta da solução do solo no campo, e então, acidificadas com HCl (2M), e imediatamente congeladas para posterior análise dos seguintes elementos: Ca, Mg, K, Fe, Zn, Mn, MOS, NO3- e NH4+. As fontes utilizadas não interferiram na dinâmica de liberação dos nutrientes para solução do solo. A condição de anaerobiose causou modificações no estado de oxirredução e alterou a solubilidade dos nutrientes na solução do solo. As doses aplicadas alteraram as concentrações de Ca e MOS na solução, sendo a dose de 150 kg ha-1 de N a dose que apresentou os maiores valores para ambos.

Le traitement thermique est basé sur la modification chimique des biopolymères par thermodégradation, en évitant l'ajout de produits chimiques. Ce traitement améliore la stabilité dimensionnelle et la durabilité fongique du bois. Ces améliorations se font au détriment des propriétés mécaniques qui ont tendance à s'affaiblir. Aujourd'hui, plusieurs types de procédés sont utilisés. Ils se distinguent entre autre par la nature du milieu dans lequelle se déroule le traitement. La durabilité de ce nouveau matériau bois est liée au degré de thermodégradation, dépendant des conditions et de l'intensité du traitement. Un pilote de traitement par conduction, travaillant sous vide ou sous azote, mesurant la masse en dynamique est utilisé afin de mieux comprendre l'influence de l'atmosphère. Les résultats obtenus montrent que l'utilisation du vide permet d'éliminer, de l'enceinte de traitement, les produits volatils formées au cours du traitement conduisant à des taux de lignine de Klason plus faibles du fait de la non recondensation des produits de dégradation. Cette limitation de recondensation des produits volatiles engendre des pertes de masse, pour une même intensité de traitement plus faibles, confirmés par des taux de polysaccharides plus élevés pour un traitement sous vide. Des études de cinétiques des réactions de thermodégradation ont confirmé la plus grande sensibilité des feuillus vis-à-vis de la thermodégradation (comparé aux résineux). De plus, ces analyses ont permis d'identifier les principaux produits de thermodégradation du bois qui varient en fonction de l'intensité du traitement et a permis de montrer une thermosensibilité plus importante de la lignine que de l'holocelluloses pour la gamme de températures utilisée. Le fruit de ces travaux est donc une progression significative des connaissances de bases sur les mécanismes de thermodégradation et leurs relations avec les paramètres de traitement / Thermal treatment is based on biopolymer chemical degradation by heat transfer, without additional chemical products impregnation. This process improves the dimensional stability and the decay resistance of wood. These improvements come at the expense of wood mechanical properties of wood which weak. Several types of heating processes exist currently differing mainly by the nature of the inert atmosphere used during treatment. The durability of this new wood material is correlated to the degree of polymers thermal degradation depending on the conditions and the treatment intensity. A conducting heat treatment pilot using nitrogen or vacuum and allowing dynamic record of mass loss is used to understand better the atmosphere influence. The results show that utilization of vacuum permit the elimination of volatile products formed during heat treatment and accumulated in oven, leading to lower extractives and Klason lignin contents due to the non recondensation of thermal degradation products. Limitation of the formation of recondensation products generates a lower mass loss for same treatment intensity and explains the lower polysaccharides degradation during a vacuum process. Fine chemical analyses and the study about thermal degradation reaction kinetics have allowed confirming the higher sensibility of hardwood than softwood to thermal degradation. In addition, these analyses have permitted the volatile thermal degradation products identification related to the treatment intensity. Subsequently, results have shown a higher thermal sensibility of lignin than holocelluloses for temperatures below 230°C. This work is a significant increase in basic knowledge about the mechanisms of wood thermal degradation and their relations with the processing parameters