Proposta de gestão ambiental para o Instituto Federal de Educação, Ciência e Tecnologia do Piauí, campus Teresina Central

Pós-graduação em Geografia - IGCE

Quais saberes são mobilizados para suprir as lacunas na formação inicial referentes à história da ciência?

Nowadays it is increasingly required insertion History of Science on content to be worked in education, which raises many doubts and difficulties on the teachers did not have that content in their initial training. This work results from a qualitative empirical study aimed to investigate how a teacher of Biology and Science in a public school in the city of Bauru - SP was not in their initial training courses relating to the History of Science, mobilizes their knowledge to enter such an approach in their teaching practice. In the research methodology used as its theme the history of DNA present in the materials and also conduct open interviews and field notes to identify the knowledge involved in teaching practice and was adopted as the theoretical framework of Maurice Tardif’s Docent Knowledge. The results showed that even with difficulties arising from gaps in initial training, the teacher resorted to their experiential knowledge to meet these needs in addition to appropriate knowledge from the programs and textbooks, but its shortcomings make it difficult to analyze more critically. Thus, these data lead us to a reflection on the role of textbooks for these teachers is the process by which the consolidation of the knowledge they constructed.

História e natureza da ciência no ensino de biologia: perfil e concepções de professores em serviço e de materiais didáticos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Rice husk derived waste materials as partial cement replacement in lightweight concrete

In this study rice husk ash (RHA) and broiler bed ash from rice husk (BBA), two agricultural waste materials, have been assessed for use as partial cement replacement materials for application in lightweight concrete. Physical and chemical characteristics of RHA and BBA were first analyzed. Three similar types of lightweight concrete were produced, a control type in which the binder was just CEMI cement (CTL) and two other types with 10% cement replacement with, respectively, RHA and BBA. All types of similar lightweight concrete were prepared to present the same workability by adjusting the amount of superplasticizer. Properties of concrete investigated were compressive and flexural strength at different ages, absorption by capillarity, resistivity and resistance to chloride ion penetration (CTH method) and accelerated carbonation. Test results obtained for 10% cement replacement level in lightweight concrete indicate that although the addition of BBA conducted to lower performance in terms of the degradation indicative tests, RHA led to the enhancement of mechanical properties, especially early strength and also fast ageing related results, further contributing to sustainable construction with energy saver lightweight concrete.

Els instruments científics dels instituts d'ensenyament mitjà: un extraordinari patrimoni cultural que hem de preservar i estudiar

Several important collections of scientific instruments are preserved in secondary schools but just a small group have been properly catalogued and studied. Unfortunately, they are not commonly regarded as a relevant part of the cultural heritage. However, recent trends in history of science offer new perspectives to study these objects from new points of view. We review some recent studies about collections of scientific instruments in secondary schools and we offer preliminary conclusions of our current work on this topic.

Pràctica 2: Anàlisi comparativa dels sistemes educatius japonès i espanyol

El currículum del segon cicle d’educació infantil a la Comunitat Valenciana queda regulat en el Decret 38/2008, que arrepleguen els diversos continguts i les diferents dimensions que cal treballar, com també el sistema d’avaluació més propici per a aquesta etapa evolutiva. El currículum es basa en els principis maduratius, així com en els aspectes que, com a societat, considerem fonamentals per al desenvolupament integral dels xiquets. No obstant això, aquests valors socials no sempre coincideixen entre cultures o països, la qual cosa pot fer variar sensiblement el currículum final. En aquesta pràctica s’analitzaran les similituds i les diferències que hi ha entre els valors i els procediments del nostre sistema educatiu i el sistema educatiu japonès. A través d’aquesta anàlisi, l’alumne podrà reflexionar sobre els diferents aspectes dels sistemes educatius, posar-los en qüestió i valorar críticament els punts forts i dèbils de cadascun.

Pràctica 8: La importància dels afectes en la infància

Un dels aspectes més importants que té rellevància quan tractem amb l’alumnat de segon cicle d’educació infantil és l’afecte, terme dins del qual també se n’engloben d’altres, tals com l’estima, la protecció, la violència o el maltractament. Per tant, es fa necessària dins d’aquesta assignatura una pràctica que faça al·lusió a la importància dels afectes en la infància. Podem disposar de l’entrevista gravada que se li fa a una especialista en el tema, Pepa Horno, psicòloga i consultora independent en infància, afectivitat i protecció des de 2004 fins a 2009 a temps parcial i des de desembre de 2009 fins a l’actualitat a temps complet com a membre del grup Espirales Consultoría de la Infancia. Les paraules de Pepa Horno, a més de les qüestions plantejades a classe, ajudaran que el nostre alumnat reflexione sobre aspectes bàsics dels afectes en la infància.

Juguem a definir la ciència: recursos per treballar el lèxic acadèmic col·laborativament

El coneixement de la ciència i la tècnica es representa i es transfereix a través de paraules que tenen un significat especialitzat, precís i concís. L’accés al coneixement especialitzat permet l’ús adequat de la terminologia. Treballar el llenguatge juntament amb el coneixement científic des dels inicis és crucial. En el projecte «Jugant a definir la ciència» (I i II) partim del supòsit que les bases del coneixement especialitzat es comencen a adquirir en els primers anys de vida d’una persona. El nostre objecte d’estudi és presentar recursos per treballar col·laborativament paraules bàsiques de la ciència a l’escola com ara aigua, espai, estrella, cervell, gel, mort, sol, calor, velocitat, aire, vida, etc. Enguany, el projecte ha saltat a la xarxa. En aquest article presentem, a més, la plataforma digital, «El club lèxic», que fomenta el treball col·laboratiu.

Ciències socials i la seua didàctica

Aquest quadern ha sorgit amb l'objectiu de facilitar el material didàctic necessari per al seguiment de l'assignatura de Ciències socials i la seua didàctica, ubicada en el segon curs de Magisteri, especialitat Educació Primària. Els alumnes d'aquesta titulació tenen un pla d'estudi molt dens, i una simple observació posa de manifest la falta de temps per atendre la seua formació. Al mateix temps els avanços tant en la didàctica com en les ciències de referència, difosos en revistes especialitzades, llibres de congressos, o temàtics, ens aconsellen realitzar una selecció i presentar una síntesi, que servesca de punt de partida per tot l'alumnat que tinga una mínima inquietud. Per aquesta raó dins dels primers capítols i activitats d'aula es presenten les principals fonts d'informació com bibliografia, hemeroteca o direccions d'Internet. La Universitat d'Alacant, conscient que molts alumnes volen estudiar en valencià, ofereix al professors, a través del Secretariat de Promoció del Valencià, l'oportunitat d'elaborar materials docents en aquesta llengua. Per tant l'objectiu d'aquest quadern també és atendre la demanda social existent i proporcionar el material didàctic bàsic pel seguiment de l'assignatura de Ciències socials i la seua didàctica. Els continguts seleccionats per al quadern estan definits pel descriptor que marca la normativa i els principis de la ciència, que el docent a presentat als seus alumnes i que han sigut avaluats a classe al llarg de cinc cursos.

Inércia e Natureza da Ciência no Ensino de Física: uma sequência didática centrada no desenvolvimento histórico do conceito de inércia

During the last decades the area of science education has discussed issues related to the inclusion of the History and Philosophy of Science (HFS) in the practice of science teaching. Among the arguments put forward in favour of this approach, it is pointed out the possible enhancement of scientific content learning and the understanding of the nature of Science (NoS). In spite of such considerations, we still have a very small number of research papers reporting results of practical interventions that utilize the historical approach, moreover, there is a lack of teaching materials in this perspective. Our work has sought to contribute to this area with regard to two aspects: on the one hand, with the production of didactic material, by drawing up texts on the history of inertia for graduate students. On the other hand, we investigate whether the arguments mentioned above in relation to the didactic use of HFS sustain themselves, in a particular context. We developed and applied a didactic sequence, using the texts that we built, to teach the concept of inertia and discuss selected contents of NoS. The didactic sequence was applied in two graduate classes, one from a course of Geophysics (BSc.) and another from the Physics (teaching formation), both from the Federal University of Rio Grande do Norte (UFRN). An initial survey exposed that students, even having approached the concept of inertia in basic education, presented conceptions of common sense regarding the relationship between force and motion. The questionnaire also allowed us to identify the existence of elements of concepts considered inadequate as regards to NoS. At the end of our research, our data indicated a greater number of positive hits on the issues concerning the concept of inertia. Regarding the aspects of NoS, we were able to identify, in a few cases, a move towards a more appropriate understanding, however, certain distortions persisted, highlighting the limitations of the approach used

Cova dels Jurats at Calescoves (Alaior, Minorca). A Cave Shrine in the Talayotic context?

Excavations carried out in the Cova dels Jurats between 2010 and 2012 served to establish that, unlike the rest of the caves Calescoves, this one functioned as a sanctuary, with two different phases. The first one corresponds to the Final Talayotic Period, as the first cave shrine documented in the Talayotic culture. In Roman times, the place was still used as a sanctuary, but with a totally different ritual, linked to the inscriptions discovered at the entrance of the cave.

A história da ciência como subsídio para a construção do conhecimento do conceito da dupla hélice

Acompanha: Dupla-hélice: a construção de um conhecimento

Hybrid materials for biomedical applications

The increased longevity of humans and the demand for a better quality of life have led to a continuous search for new implant materials. Scientific development coupled with a growing multidisciplinarity between materials science and life sciences has given rise to new approaches such as regenerative medicine and tissue engineering. The search for a material with mechanical properties close to those of human bone produced a new family of hybrid materials that take advantage of the synergy between inorganic silica (SiO4) domains, based on sol-gel bioactive glass compositions, and organic polydimethylsiloxane, PDMS ((CH3)2.SiO2)n, domains. Several studies have shown that hybrid materials based on the system PDMS-SiO2 constitute a promising group of biomaterials with several potential applications from bone tissue regeneration to brain tissue recovery, passing by bioactive coatings and drug delivery systems. The objective of the present work was to prepare hybrid materials for biomedical applications based on the PDMS-SiO2 system and to achieve a better understanding of the relationship among the sol-gel processing conditions, the chemical structures, the microstructure and the macroscopic properties. For that, different characterization techniques were used: Fourier transform infrared spectrometry, liquid and solid state nuclear magnetic resonance techniques, X-ray diffraction, small-angle X-ray scattering, smallangle neutron scattering, surface area analysis by Brunauer–Emmett–Teller method, scanning electron microscopy and transmission electron microscopy. Surface roughness and wettability were analyzed by 3D optical profilometry and by contact angle measurements respectively. Bioactivity was evaluated in vitro by immersion of the materials in Kokubos’s simulated body fluid and posterior surface analysis by different techniques as well as supernatant liquid analysis by inductively coupled plasma spectroscopy. Biocompatibility was assessed using MG63 osteoblastic cells. PDMS-SiO2-CaO materials were first prepared using nitrate as a calcium source. To avoid the presence of nitrate residues in the final product due to its potential toxicity, a heat-treatment step (above 400 °C) is required. In order to enhance the thermal stability of the materials subjected to high temperatures titanium was added to the hybrid system, and a material containing calcium, with no traces of nitrate and the preservation of a significant amount of methyl groups was successfully obtained. The difficulty in eliminating all nitrates from bulk PDMS-SiO2-CaO samples obtained by sol-gel synthesis and subsequent heat-treatment created a new goal which was the search for alternative sources of calcium. New calcium sources were evaluated in order to substitute the nitrate and calcium acetate was chosen due to its good solubility in water. Preparation solgel protocols were tested and homogeneous monolithic samples were obtained. Besides their ability to improve the bioactivity, titanium and zirconium influence the structural and microstructural features of the SiO2-TiO2 and SiO2-ZrO2 binary systems, and also of the PDMS-TiO2 and PDMS-ZrO2 systems. Detailed studies with different sol-gel conditions allowed the understanding of the roles of titanium and zirconium as additives in the PDMS-SiO2 system. It was concluded that titanium and zirconium influence the kinetics of the sol-gel process due to their different alkoxide reactivity leading to hybrid xerogels with dissimilar characteristics and morphologies. Titanium isopropoxide, less reactive than zirconium propoxide, was chosen as source of titanium, used as an additive to the system PDMS-SiO2-CaO. Two different sol-gel preparation routes were followed, using the same base composition and calcium acetate as calcium source. Different microstructures with high hydrophobicit were obtained and both proved to be biocompatible after tested with MG63 osteoblastic cells. Finally, the role of strontium (typically known in bioglasses to promote bone formation and reduce bone resorption) was studied in the PDMS-SiO2-CaOTiO2 hybrid system. A biocompatible material, tested with MG63 osteoblastic cells, was obtained with the ability to release strontium within the values reported as suitable for bone tissue regeneration.

Hydric behavior of earth materials and the effects of their stabilization with cement or lime: study on repair mortars for historical rammed earth structures

Earthen building materials bear interesting environmental advantages and are the most appropriate to conserve historical earth constructions. To improve mechanical properties, these materials are often stabilized with cement or lime, but the impact of the stabilizers on the water transport properties, which are also critical, has been very rarely evaluated. We have tested four earth-based repair mortars applied on three distinct and representative rammed earth surfaces. Three mortars are based on earth collected from rammed earth buildings in south of Portugal and the fourth mortar is based on a commercial clayish earth. The main objective of the work was over the commercial earth mortar, applied stabilized and not stabilized on the three rammed earth surfaces to repair, to assess the influence of the stabilizers. The other three earth mortars (not stabilized) were applied on each type of rammed earth, representing the repair only made with local materials. The four unstabilized earth materials depicted nonlinear dependence on t1/2 during capillary suction. This behaviour was probably due to clay swelling. Stabilization with any of the four tested binders enabled the linear dependence of t1/2 expected from Washburn's equation, probably because the swelling did not take place in this case. However, the stabilizers also increased significantly the capillary suction and the capillary porosity of the materials. This means that, in addition to increasing the carbon footprint, stabilizers like cement and lime have functional disadvantages that discourage its use in repair mortars for raw earth construction.