968 resultados para proximate purposes
Resumo:
This thesis deals with the use of inquiry-based approaches in primary school science. The aim is to investigate the goals and purposes that are constituted by the curriculum and by the teachers in interviews and through their teaching in the classroom. The results are used to develop conceptual tools that can be used by teachers’ in their work to support students’ learning of science when using an inquiry-based approach. The thesis is comprised of four papers. In paper one a comparative analysis is made of five Swedish national curricula for compulsory school regarding what students should learn about scientific inquiry. In paper two 20 teachers were interviewed about their own teaching using inquiry. Classroom interactions were filmed and analyzed in papers three and four, which examine how primary teachers use the various activities and purposes of the inquiry classroom to support learning progressions in science. The results of paper one show how the emphasis within and between the two goals of learning to carry out investigations and learning about the nature of science shifted and changed over time in the different curricula. Paper two describes the selective traditions and qualities that were emphasized in the teachers’ accounts of their own teaching. The results of papers three and four show how students need to be involved in the proximate and ultimate purposes of the teaching activities for progression to happen. The ultimate purposes are the scientific purposes for the lesson (as given by the teacher or by the curriculum), whereas the proximate purposes are the more student-centered purposes that through different activities should allow the students to relate their own experiences and language to the ultimate purpose. The results show the importance of proximate purposes working as ends-in-viewin the sense of John Dewey, meaning that the students see the goal of the activity and that they are able to relate to their experiences and familiar language.
Resumo:
This dissertation was an analysis of the root and proximate causes of the September 2002 civil war in Côte d’Ivoire. The central question of this study was: Why did Côte d’Ivoire, which was relatively stable under President Houphouët-Boigny, suddenly begin to experience political violence in the 1990s and an explosion in 2002? Côte d’Ivoire was an interesting case because it was stable for a long period of time, apparently making it an infertile ground for conflict. It was also interesting for comparative purposes because of the fact that several states in West Africa (for instance, Benin, Togo, and Ghana) have experienced military coups but not have civil wars. Finally, this case was an opportunity to revisit the debate on the causes of civil wars in the African context. Chapter one has outlined the entire dissertation project and contextualized the analysis that follows in the subsequent chapters. Chapter two has reviewed the literature on civil wars in general, identified the different types of civil wars, and the type the Ivoiran war is. Chapter three has examined the domestic and international political economy as a source of the civil violence in Côte d’Ivoire. Chapter four has examined the role of ethnicity and region as identities of the war, while chapter five has analyzed the role of the foreign relations in the civil war, as well as the regional political context. Chapter six has distinguished between the root and proximate causes of the Ivoirian civil war, made judgments about the relative weight of the various causes, and the extent to which the weight of the causes can be measured. The study found that the “Ivoirité” was the most important trigger of the civil war in Côte d’Ivoire. The overall conclusion of my dissertation was that the September 2002 crisis in that country was a political crisis which occured in the context of a political reform. It first started with succession problems in 1993 followed by the controversial elections in 1995 and 2000. Later, this electoral politics spread beyond electoral issues, namely citizenship matters.
Resumo:
This dissertation was an analysis of the root and proximate causes of the September 2002 civil war in Côte d’Ivoire. The central question of this study was: Why did Côte d’Ivoire, which was relatively stable under President Houphouët-Boigny, suddenly begin to experience political violence in the 1990s and an explosion in 2002? Côte d’Ivoire was an interesting case because it was stable for a long period of time, apparently making it an infertile ground for conflict. It was also interesting for comparative purposes because of the fact that several states in West Africa (for instance, Benin, Togo, and Ghana) have experienced military coups but not have civil wars. Finally, this case was an opportunity to revisit the debate on the causes of civil wars in the African context. Chapter one has outlined the entire dissertation project and contextualized the analysis that follows in the subsequent chapters. Chapter two has reviewed the literature on civil wars in general, identified the different types of civil wars, and the type the Ivoiran war is. Chapter three has examined the domestic and international political economy as a source of the civil violence in Côte d’Ivoire. Chapter four has examined the role of ethnicity and region as identities of the war, while chapter five has analyzed the role of the foreign relations in the civil war, as well as the regional political context. Chapter six has distinguished between the root and proximate causes of the Ivoirian civil war, made judgments about the relative weight of the various causes, and the extent to which the weight of the causes can be measured. The study found that the “Ivoirité” was the most important trigger of the civil war in Côte d’Ivoire. The overall conclusion of my dissertation was that the September 2002 crisis in that country was a political crisis which occured in the context of a political reform. It first started with succession problems in 1993 followed by the controversial elections in 1995 and 2000. Later, this electoral politics spread beyond electoral issues, namely citizenship matters.
Resumo:
Borututu ( Cochlospermum angolensis Welw.) is a widespread tree in Angola used since antiquity by traditional healers for the prevention and treatment of hepatic diseases and for the prophylaxis of malaria [1]. This plant is mostly consumed as infusions but is also available as dietary supplements, such as piiis, capsules, and syrups, among others. In the present study, the aim was to evaluate the proximate composition and energetic contribution of borututu as weii as its composition in hydrophilic (sugars and organic acids) and lipophilic (fatty acids and tocopherols) compounds, given the fact that this plant is directly introduced in some dietary supplements. Furthermore, the bioactivity (antioxidant, hepatoprotective and antimicrobial activities) of three different formulations of borututu (infusion, pills, and syrup) was assessed and compared, and since plant beneficial properties are often ascribed to phenolic compounds [2], the phenolic profile of the formulations was also analysed. Carbohydrates (88 g/100 g) and fat (2.5 g/100 g) were the major and tl1e minor components of the studied borututu dry barks, respectively, with an energetic contribution of 384 kcal/100 g. Fructose was the most abundant sugar (1.3 g/100 g), foilowed by sucrose, trehalose and glucose (1.1, 0.98 and 0.79 g/100 g, respectively). Oxalic (0.70 g/100 g), malic (0.63 g/100 g) and citric (0.57 g/100 g) acids were present in higher amounts but shikimic and fumaric acids were also detected. Among the fatty acids found in borututu, a prevalence of saturated fatty acids (SF A; 48.2%) was observed, whereas polyunsaturated (PUFA) and monounsaturated (MUFA) fatty acids were detected in relative percentages of 30.9% and 20.8%, respectively. P-tocopherol was the most abundant of the four isoforms found in the sample, foiiowed by o-, a- and y-tocopherol, present in concentrations of 597,43, 3.7 and 2.0 g/100 g, respectively. Borututu infusion revealed the highest antioxidant activity, with EC50 values ranging from 20 to 600 J.lg/mL and was the only formulation inhibiting the growth of an HepG2 ceii line, with a Gl5o value of 146 J.lg/mL. This formulation.also revealed the best antimicrobial capacity and proved to be able to inhibit the growth of Escherichia coli, E. coli ESBL, Staphylococcus aureus and Pseudomonas aeruginosa, with MIC values of 50, 6.2, 1.6 and 25 mg!mL, respectively. Pills revealed activity against some of the studied bacterial strains and the syrup did not reveal antimicrobial activity at the studied concentration. Eilagic acids, methyl ellagic acids, eucaglobulinlglobulusin B and (epi)gaiiocatechin-0-gallate were the compounds present in all the different formulations. The highest concentration of phenolic compounds was found in the infusion extract. Protocatechuic acid was the most abundant phenolic compound in the infusions, the only preparation where it was detected, whereas ( epi)gaiiocatechin- 0-gallate was the main phenolic in the pills and eucaglobulinlglobulusin in the syrup. In a general way, borututu proved to be a good source of phytochemicals such as phenolic compounds, with the infusions revealing the best bioactive properties.
Resumo:
Opuntia spp. flowers have been traditionally used for medical purposes, mostly because of their diversity in bioactive molecules with health promoting properties. The proximate, mineral and volatile compound profiles, together with the cytotoxic and antimicrobial properties were characterized in O. microdasys flowers at different maturity stages, revealing several statistically significant differences. O. microdasys stood out mainly for its high contents of dietary fiber, potassium and camphor, and its high activities against HCT15 cells, Staphylococcus aureus, Aspergillus versicolor and Penicillium funiculosum. The vegetative stage showed the highest cytotoxic and antifungal activities, whilst the full flowering stage was particularly active against bacterial species. The complete dataset has been classified by principal component analysis, achieving clearly identifiable groups for each flowering stage, elucidating also the most distinctive features, and comprehensively profiling each of the assayed stages. The results might be useful to define the best flowering stage considering practical application purposes.
Resumo:
Objective: This study evaluated with histochemical analysis how the number of laser applications can affect the masseter muscle. Background: In dentistry today, the laser is used in patients with temporomandibular disorders (TMDs), mainly for radiating pain in the masticatory muscles, whose origins may be associated with malocclusion, although the laser effects are not well understood on the cellular level. Materials and Methods: Thirty mice (HRS/J lineage) were randomly distributed into groups according to the number of laser applications (three, six, and 10). For each group of laser applications (experimental, n = 5), it was considered the control group (n = 5), which was not irradiated. All animals inhaled halothane (2-bromo-2-chloro-1, 1, 1-trifluoroethane, minimum 99%, Sigma Aldrich, India) before each laser irradiation performed on the left masseter muscle region, on alternate days with 20 J/cm(2), 40mW, for 20 sec. The muscle samples were collected for histochemical analysis with succinate dehydrogenase (SDH) enzyme 72 h after the last application. Results: (a) A decrease in area of light fibers type (35.91% +/- 6.9%; 32.08% +/- 6.3%, and 27.88% +/- 6.3%), according to the increase of laser applications (p < 0.05); (b) significant increase (p < 0.05) in the area of intermediate fibers, with an increase of laser application (11.08% +/- 3.9%; 16.52% +/- 5.7%, and 15.96% +/- 3.9%), although the increase with 10 applications was small; (c) area increase of dark fibers in the group with three laser applications (0.16% +/- 0.3%) (p < 0.05), and in groups with six and 10 laser applications, respectively (9.68% +/- 6.0% and 9.60% +/- 4.0%). Conclusions: The SDH enzyme activity revealed that the number of laser applications increases the metabolic pattern of the muscle fibers. A minimal difference in metabolic activity between six and 10 applications of a laser suggests that further analyses should be done to confirm that six applications are enough to produce the same clinical effects, thereby contributing data to professionals from different fields in regard to the cost-benefit ratio of this therapy.
Resumo:
This article presents a fieldbus simulation platform and its remote access interface that enables a wide range of experiments, where users can configure operation sequences and procedures typical of Foundation Fieldbus systems. The simulation system was developed using LabVIEW, with requisites of deterministic execution, and a course management work frame web server called Moodle. The results were obtained through three different evaluations: schedule table execution, simulator functionality and finally, simulator productivity and achievement. The evaluation attests that this new tool is feasible, and can be applied for fieldbus automation systems training purposes, considering the robustness and stability in tests and the positive feedback from users. (C) 2008 ISA. Published by Elsevier Ltd. All rights reserved.
Resumo:
A geometrical approach of the finite-element analysis applied to electrostatic fields is presented. This approach is particularly well adapted to teaching Finite Elements in Electrical Engineering courses at undergraduate level. The procedure leads to the same system of algebraic equations as that derived by classical approaches, such as variational principle or weighted residuals for nodal elements with plane symmetry. It is shown that the extension of the original procedure to three dimensions is straightforward, provided the domain be meshed in first-order tetrahedral elements. The element matrices are derived by applying Maxwell`s equations in integral form to suitably chosen surfaces in the finite-element mesh.
Resumo:
A technique is described to preserve the pigment found in the bodies and the intestine of some brightly coloured and darkly pigmented benedeniine capsalid monogeneans. Previous studies of these pigmented capsalids have proven difficult because the pigmentation usually disappears when the worms are fixed using preservatives containing concentrations of formalin over 5% and/or ethanol, acetic acid, chromic acid, picric acid and mercuric chloride. The technique developed here uses a fixative comprising glycerol, acetone and formalin (GAF). After fixation under light coverslip compression for three minutes, specimens are transferred to absolute acetone for three minutes and cleared in a mixture of nine parts cedar wood oil and one part absolute acetone before mounting in Canada balsam. Processing must be carried out quickly, as these chemicals will cause the pigments to fade if the specimens are exposed to them for too long. Pigmented benedeniines processed using this technique retain the distribution, intensity and colour observed in live worms. The colour and distribution of pigmentation in monogeneans may be of taxonomic importance and this technique aids preparation of whole-mounts suitable for registration as type-material.
Resumo:
Computer assisted learning has an important role in the teaching of pharmacokinetics to health sciences students because it transfers the emphasis from the purely mathematical domain to an 'experiential' domain in which graphical and symbolic representations of actions and their consequences form the major focus for learning. Basic pharmacokinetic concepts can be taught by experimenting with the interplay between dose and dosage interval with drug absorption (e.g. absorption rate, bioavailability), drug distribution (e.g. volume of distribution, protein binding) and drug elimination (e.g. clearance) on drug concentrations using library ('canned') pharmacokinetic models. Such 'what if' approaches are found in calculator-simulators such as PharmaCalc, Practical Pharmacokinetics and PK Solutions. Others such as SAAM II, ModelMaker, and Stella represent the 'systems dynamics' genre, which requires the user to conceptualise a problem and formulate the model on-screen using symbols, icons, and directional arrows. The choice of software should be determined by the aims of the subject/course, the experience and background of the students in pharmacokinetics, and institutional factors including price and networking capabilities of the package(s). Enhanced learning may result if the computer teaching of pharmacokinetics is supported by tutorials, especially where the techniques are applied to solving problems in which the link with healthcare practices is clearly established.
Resumo:
Cleaning behavior is a popular example of non-kin cooperation. However, quantitative support for this is generally sparse and the alternative, that cleaners are parasitic: has also been proposed. Although the behaviour involves some of the most complex and highly developed interspecific communication signals known, the proximate causal factors for why clients Seek cleaners are controversial. However, this information is essential to understanding the evolution of cleaning. I tested whether clients seek cleaners in response to parasite infection or whether clients seek cleaners for tactile stimulation regardless of parasite load. Parasite loads oil client fish were manipulated and clients exposed to cleaner fish and control fish hehind glass. I found that parasitized client fish spent more time than unparasitized fish next to a cleaner fish. In addition; parasitized clients spent more rime next to cleaners than next to control fish whereas unparasitized fish were not attracted to cleaners. This study shows, I believe for the first time, which is somewhat surprising, that parasite infection alone causes clients to seek cleaning by cleaners and provides insight into how this behaviour evolved.