11 resultados para practical diets
em Helda - Digital Repository of University of Helsinki
Resumo:
The present study addressed the epistemology of teachers’ practical knowledge. Drawing from the literature, teachers’ practical knowledge is defined as all teachers’ cognitions (e.g., beliefs, values, motives, procedural knowing, and declarative knowledge) that guide their practice of teaching. The teachers’ reasoning that lies behind their practical knowledge is addressed to gain insight into its epistemic nature. I studied six class teachers’ practical knowledge; they teach in the metropolitan region of Helsinki. Relying on the assumptions of the phenomenographic inquiry, I collected and analyzed the data. I analyzed the data in two stages where the first stage involved an abductive procedure, and the second stage an inductive procedure for interpretation, and thus developed the system of categories. In the end, a quantitative analysis nested into the qualitative findings to study the patterns of the teachers’’ reasoning. The results indicated that teachers justified their practical knowledge based on morality and efficiency of action; efficiency of action was found to be presented in two different ways: authentic efficiency and naïve efficiency. The epistemic weight of morality was embedded in what I call “moral care”. The core intention of teachers in the moral care was the commitment that they felt about the “whole character” of students. From this perspective the “dignity” and the moral character of the students should not replaced for any other “instrumental price”. “Caring pedagogy” was the epistemic value of teachers’ reasoning in the authentic efficiency. The central idea in the caring pedagogy was teachers’ intentions to improve the “intellectual properties” of “all or most” of the students using “flexible” and “diverse” pedagogies. However, “regulating pedagogy” was the epistemic condition of practice in the cases corresponding to naïve efficiency. Teachers argued that an effective practical knowledge should regulate and manage the classroom activities, but the targets of the practical knowledge were mainly other “issues “or a certain percentage of the students. In these cases, the teachers’ arguments were mainly based on the notion of “what worked” regardless of reflecting on “what did not work”. Drawing from the theoretical background and the data, teachers’ practical knowledge calls for “praxial knowledge” when they used the epistemic conditions of “caring pedagogy” and “moral care”. It however calls for “practicable” epistemic status when teachers use the epistemic condition of regulating pedagogy. As such, praxial knowledge with the dimensions of caring pedagogy and moral care represents the “normative” perspective on teachers’ practical knowledge, and thus reflects a higher epistemic status in comparison to “practicable” knowledge, which represents a “descriptive” perception toward teachers’ practical knowledge and teaching.
Resumo:
The first aim of this thesis was to produce data for evaluating, developing and recommending biologically and economically efficient energy and protein feeding strategies for growing and finishing dairy bulls offered grass silage-based diets. The second aim was to calculate the energy and protein supplies of the dairy bulls fed different grass silage-cereal-based diets and, based on this, to estimate the possible need to revise the current Finnish energy and protein recommendations for growing dairy bulls. The third aim was to demonstrate the phosphorus supply of dairy bulls fed grass silage-cereal-based diets with or without protein supplementation in relation to current feeding recommendations for phosphorus. The results indicate that protein supplement is not needed for finishing dairy bulls (live weight more than 250 kg) when they are fed good-quality grass silage (digestible organic matter more than 650 g/kg dry matter, restricted fermentation with low concentrations of fermentation acids and ammonia N) and grain-based concentrate with a moderate (300-700 g/kg dry matter) concentrate level. The results also suggest that with total mixed ration feeding it is possible to use rather high concentrate proportions (700 g/kg dry matter) in feeding dairy bulls. According to this study, barley fibre is a suitable energy supplement with good-quality silage for growing dairy bulls. The results suggest that 50% of barley grain can be replaced with barley fibre without affecting growth. Also oats is a suitable energy supplement for dairy bulls. However, as a consequence of decreased energy intake, the gain and feed conversion of the bulls were slightly reduced in this study when barley grain was replaced by oats in the diet. Ultimately, the rationality of the use of barley fibre and oats in the future will depend on the price in relation to other concentrates. During the feeding experiments the calculated supply of energy was 10% higher than in the Finnish feeding recommendations for the present growth rate. This indicates that there is a need to update the Finnish feeding recommendations for dairy-breed growing bulls, and further calculations are needed for the energy supply of growing dairy bulls. The calculated supply of AAT (amino acids absorbed from the small intestine) was 38% higher than in the Finnish feeding recommendations for the present growth. Possibly, the present AAT-PBV system is not an optimal protein evaluation system for growing dairy bulls more than 250 kg live weight. The calculations based on the feeding experiments and the Finnish feeding recommendations indicate that in most cases the dairy bulls (live weight more than 250 kg) received enough P from the basic grass silage cereal-based diets without additional mineral feeds. Therefore there is no need to add P in the form of mineral mixtures.
Resumo:
The main objective of this thesis was to elucidate the effects of regrowth grass silage and red clover silage on nutrient supply and milk production of dairy cows as compared with primary growth grass silages. In the first experiment (publication I), two primary growth and four regrowth grass silages were harvested at two stages of growth. These six silages were fed to 24 lactating dairy cows with two levels of concentrate allowance. Silage intake and energy corrected milk yield (ECM) responses, and the range in these response variables between the diets, were smaller when regrowth silages rather than primary growth silages were fed. Milk production of dairy cows reflected the intake of metabolizable energy (ME), and no differences in the ME utilization were found between the diets based on silages harvested from primary growth and regrowth. The ECM response to increased concentrate allowance was, on average, greater when regrowth rather than primary growth silages were fed. In the second experiment (publication II), two silages from primary growth and two from regrowth used in I were fed to rumen cannulated lactating dairy cows. Cows consumed less feed dry matter (DM), energy and protein, and produced less milk, when fed diets based on regrowth silages rather than primary growth silages. Lower milk production responses of regrowth grass silage diets were mainly due to the lower silage DM intake, and could not be accounted for by differences in energy or protein utilization. Regrowth grass silage intake was not limited due to neutral detergent fibre (NDF) digestion or rumen fill or passage kinetics. However, lower intake may be at least partly attributable to plant diseases such as leaf spot infections, dead deteriorating material or abundance of weeds, which are all higher in regrowth compared with primary growth, and increase with advancing regrowth. In the third experiment (publications III and IV), red clover silages and grass silages harvested at two stages of growth, and a mixed diet of red clover and grass silages, were fed to five rumen cannulated lactating dairy cows. In spite of the lower average ME intake for red clover diets, the ECM production remained unchanged suggesting more efficient utilisation of ME for red clover diets compared with grass diets. Intake of N, and omasal canal flows of total non-ammonia N (NAN), microbial and non-microbial NAN were higher for red clover than for grass silage diets, but were not affected by forage maturity. Delaying the harvest tended to decrease DM intake of grass silage and increase that of red clover silage. The digestion rate of potentially digestible NDF was faster for red clover diets than for grass silage diets. Delaying the harvest decreased the digestion rate for grass but increased it for red clover silage diets. The low intake of early-cut red clover silage could not be explained by silage digestibility, fermentation quality, or rumen fill but was most likely related to the nutritionally suboptimal diet composition because inclusion of moderate quality grass silage in mixed diet increased silage DM intake. Despite the higher total amino acid supply of cows fed red clover versus grass silage diets, further milk production responses on red clover diets were possibly compromised by an inadequate supply of methionine as evidenced by lower methionine concentration in the amino acid profile of omasal digesta and plasma. Increasing the maturity of ensiled red clover does not seem to affect silage DM intake as consistently as that of grasses. The efficiency of N utilization for milk protein synthesis was lower for red clover diets than for grass diets. It was negatively related to diet crude protein concentration similarly to grass silage diets.
Resumo:
Cardiovascular diseases (CVDs) are the leading cause of mortality in the world. Studies of the impact of single nutrients on the risk for CVD have often provided inconclusive results, and recent research in nutritional epidemiology with a more holistic whole-diet approach has proven fruitful. Moreover, dietary habits in childhood and adolescence may play a role in later health and disease, either independently or by tracking into adulthood. The main aims of this study were to find childhood and adulthood determinants of adulthood diet, to identify dietary patterns present among the study population and to study the associations between long-term food choices and cardiovascular health in young Finnish adults. The study is a part of the multidisciplinary Cardiovascular Risk in Young Finns study, which is an ongoing, prospective cohort study with a 21-year follow-up. At baseline in 1980, the subjects were children and adolescents aged 3 to 18 years (n included in this study = 1768), and young adults aged 24 to 39 years at the latest follow-up study in 2001 (n = 1037). Food consumption and nutrient intakes were assessed with repeated 48-hour dietary recalls. Other determinations have included comprehensive risk factor assessments using blood tests, physical measurements and questionnaires. In the latest follow-up, ultrasound examinations were performed to study early atherosclerotic vascular changes. The average intakes showed substantial changes since 1980. Intakes of fat and saturated fat had decreased, whereas the consumption of fruits and vegetables had increased. Intake of fat and consumption of vegetables in childhood and physical activity in adulthood were important health behavioural determinants of adult diet. Additionally, a principal component analysis was conducted to identify major dietary patterns at each study point. A similar set of two major patterns was recognised throughout the study. The traditional dietary pattern positively correlated with the consumption of traditional Finnish foods, such as rye, potatoes, milk, butter, sausages and coffee, and negatively correlated with fruit, berries and dairy products other than milk. This type of diet was independently associated with several risk factors of CVD, such as total and low-density lipoprotein cholesterol, apolipoprotein B and C-reactive protein concentrations among both genders, as well as with systolic blood pressure and insulin levels among women. The traditional pattern was also independently associated with intima media thickness (IMT), a subclinical predictor of CVD, in men but not in women. The health-conscious pattern, predominant among female subjects, non-smokers and urbanites, was characterised by more health-conscious food choices such as vegetables, legumes and nuts, tea, rye, fish, cheese and other dairy products, as well as by the consumption of alcoholic beverages. This pattern was inversely, but less strongly, associated with cardiovascular risk factors. Tracking of the dietary pattern scores was observed, particularly among subjects who were adolescents at baseline. Moreover, a long-term high intake of protein concurrent with a low intake of fat was positively associated with IMT. These findings suggest that food behaviour and food choices are to some extent established as early as in childhood or adolescence and may significantly track into adulthood. Long-term adherence to traditional food choices seems to increase the risk for developing CVD, especially among men. Those with intentional or unintentional low fat diets, but with high intake of protein may also be at increased risk for CVD. The findings offer practical, food-based information on the relationship between diet and CVD and encourage further use of the whole-diet approach in epidemiological research. The results support earlier findings that long-term food choices play a role in the development of CVD. The apparent influence of childhood habits is important to bear in mind when planning educational strategies for the primary prevention of CVD. Further studies on food choices over the entire lifespan are needed.
Resumo:
Taking the appropriation of objects as a theoretical starting point, this study makes a distinction between a conceptual and practical level of adopting new objects and products in everyday life. The study applies the concept of appropriation in social food research and examines consumers appropriation of functional foods, i.e., foods developed to improve health and well-being or reduce the risk of disease beyond the usual nutritional effects of foods. The study uses the concept of appropriation to understand the adoption and the process of making functional foods our own . First, the study focuses on the conceptual appropriation by analysing consumers interpretations and opinions on functional foods. Second, it analyses the use of functional foods and examines the role of sociodemographic and food- and health-related background factors in the use of functional foods. Both quantitative and qualitative data were used in the study. Altogether 1210 Finns representative of the population took part in a survey carried out in 2002 as computer-assisted telephone interviews (CATI). The survey examined the acceptability and use of functional foods in Finland. In 2004, eight focus group discussions were organised for 45 users and non-users of cholesterol-lowering spreads. The qualitative study focused on consumers interpretative perspectives on healthy eating and functional foods. The findings are reported in four original articles and a summary article. The results show that the appropriation of functional foods is a multifaceted phenomenon. The conceptual appropriation is related to consumers interpretations of functional foods in the context of healthy foods and healthy eating; their trust in the products, their manufacturers, research and control; and the relationship of functional foods and the ideal of natural foods. The analysis of the practical appropriation of four different types of foods marketed as functional showed that there are sociodemographic differences between users and non-users of the products, but more importantly, the differences are related to consumers food- and health-related views and practices. Consumers ways of appropriating functional foods in the conceptual and practical sense take shape in a complex web of ideas and everyday practices concerning food, health and eating as a whole. The results also indicate that the conceptual and practical appropriation are not necessarily uniform or coherent processes. Consumers interpret healthy eating and functional foods from a variety of perspectives and there is a multiplicity of rationales of using functional foods. Appropriation embraces many opposing dimensions simultaneously: good experiences and doubts, approval and criticism, expectations and things taken for granted.
Resumo:
The purpose of this study is to examine how transformation is defining feminist bioethics and to determine the nature of this transformation. Behind the quest for transformation is core feminism and its political implications, namely, that women and other marginalized groups have been given unequal consideration in society and the sciences and that this situation is unacceptable and should be remedied. The goal of the dissertation is to determine how feminist bioethicists integrate the transformation into their respective fields and how they apply the potential of feminism to bioethical theories and practice. On a theoretical level, feminist bioethicists wish to reveal how current ways of knowing are based on inequality. Feminists pay special attention especially to communal and political contexts and to the power relations endorsed by each community. In addition, feminist bioethicists endorse relational ethics, a relational account of the self in which the interconnectedness of persons is important. On the conceptual level, feminist bioethicists work with beliefs, concepts, and practices that give us our world. As an example, I examine how feminist bioethicists have criticized and redefined the concept of autonomy. Feminist bioethicists emphasize relational autonomy, which is based on the conviction that social relationships shape moral identities and values. On the practical level, I discuss stem cell research as a test case for feminist bioethics and its ability to employ its methodologies. Analyzing these perspectives allowed me first, to compare non-feminist and feminist accounts of stem cell ethics and, second, to analyze feminist perspectives on the novel biotechnology. Along with offering a critical evaluation of the stem cell debate, the study shows that sustainable stem cell policies should be grounded on empirical knowledge about how donors perceive stem cell research and the donation process. The study indicates that feminist bioethics should develop the use of empirical bioethics, which takes the nature of ethics seriously: ethical decisions are provisional and open for further consideration. In addition, the study shows that there is another area of development in feminist bioethics: the understanding of (moral) agency. I argue that agency should be understood to mean that actions create desires.
Resumo:
In this article we introduce and evaluate testing procedures for specifying the number k of nearest neighbours in the weights matrix of spatial econometric models. The spatial J-test is used for specification search. Two testing procedures are suggested: an increasing neighbours testing procedure and a decreasing neighbours testing procedure. Simulations show that the increasing neighbours testing procedures can be used in large samples to determine k. The decreasing neighbours testing procedure is found to have low power, and is not recommended for use in practice. An empirical example involving house price data is provided to show how to use the testing procedures with real data.