8 resultados para <20 µm

em Helda - Digital Repository of University of Helsinki


Relevância:

20.00% 20.00%

Publicador:

Resumo:

From Arithmetic to Algebra. Changes in the skills in comprehensive school over 20 years. In recent decades we have emphasized the understanding of calculation in mathematics teaching. Many studies have found that better understanding helps to apply skills in new conditions and that the ability to think on an abstract level increases the transfer to new contexts. In my research I take into consideration competence as a matrix where content is in a horizontal line and levels of thinking are in a vertical line. The know-how is intellectual and strategic flexibility and understanding. The resources and limitations of memory have their effects on learning in different ways in different phases. Therefore both flexible conceptual thinking and automatization must be considered in learning. The research questions that I examine are what kind of changes have occurred in mathematical skills in comprehensive school over the last 20 years and what kind of conceptual thinking is demonstrated by students in this decade. The study consists of two parts. The first part is a statistical analysis of the mathematical skills and their changes over the last 20 years in comprehensive school. In the test the pupils did not use calculators. The second part is a qualitative analysis of the conceptual thinking of pupils in comprehensive school in this decade. The study shows significant differences in algebra and in some parts of arithmetic. The largest differences were detected in the calculation skills of fractions. In the 1980s two out of three pupils were able to complete tasks with fractions, but in the 2000s only one out of three pupils were able to do the same tasks. Also remarkable is that out of the students who could complete the tasks with fractions, only one out of three pupils was on the conceptual level in his/her thinking. This means that about 10% of pupils are able to understand the algebraic expression, which has the same isomorphic structure as the arithmetical expression. This finding is important because the ability to think innovatively is created when learning the basic concepts. Keywords: arithmetic, algebra, competence

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Dietary habits have changed during the past decades towards an increasing consumption of processed foods, which has notably increased not only total dietary phosphorus (P) intake, but also intake of P from phosphate additives. While the intake of calcium (Ca) in many Western countries remains below recommended levels (800 mg/d), the usual daily P intake in a typical Western diet exceeds by 2- to 3-fold the dietary guidelines (600 mg/d). The effects of high P intake in healthy humans have been investigated seldom. In this thesis healthy 20- to 43-year-old women were studied. In the first controlled study (n = 14), we examined the effects of P doses, and in a cross-sectional study (n = 147) the associations of habitual P intakes with Ca and bone metabolism. In this same cross-sectional study, we also investigated whether differences exist between dietary P originating from natural P sources and phosphate additives. The second controlled study (n = 12) investigated whether by increasing the Ca intake, the effects of a high P intake could be reduced. The associations of habitual dietary calcium-to-phosphorus ratios (Ca:P ratio) with Ca and bone metabolism were determined in a cross-sectional study design (n = 147). In the controlled study, the oral intake of P doses (495, 745, 1245 and 1995 mg/d) with a low Ca intake (250 mg/d) increased serum parathyroid hormone (S-PTH) concentration in a dose-dependent manner. In addition, the highest P dose decreased serum ionized calcium (S-iCa) concentration and bone formation and increased bone resorption. In the second controlled study with a dietary P intake of 1850 mg/d, by increasing the Ca intake from 480 mg/d to 1080 mg/d and then to 1680 mg/d, the S-PTH concentration decreased, the S-iCa concentration increased and bone resorption decreased dose-dependently. However, not even the highest Ca intake could counteract the effect of high dietary P on bone formation, as indicated by unchanged bone formation activity. In the cross-sectional studies, a higher habitual dietary P intake (>1650 mg/d) was associated with lower S-iCa and higher S-PTH concentrations. The consumption of phosphate additive-containing foods was associated with a higher S-PTH concentration. Moreover, habitual low dietary Ca:P ratios (≤0.50, molar ratio) were associated with higher S-PTH concentrations and 24-h urinary Ca excretions, suggesting that low dietary Ca:P ratios may interfere with homeostasis of Ca metabolism and increase bone resorption. In summary, excessive dietary P intake in healthy Finnish women seems to be detrimental to Ca and bone metabolism, especially when dietary Ca intake is low. The results indicate that by increasing dietary Ca intake to the recommended level, the negative effects of high P intake could be diminished, but not totally prevented. These findings imply that phosphate additives may be more harmful than natural P. Thus, reduction of an excessively high dietary P intake is also beneficial for healthy individuals.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A View into the World of Kitchen: Development and retention of a leading position in the market of kitchen interiors - a case study of 20 years. This study focuses on the development of a kitchen interiors company, presently called Novart Inc., into the leading company of the industry from 1980´s to the present. The objective of the study is to describe the effects of strategic choices, the decisions of the management and the owner´s direction and control to the build up and the retaining of the leading position in the market. From theory point of view, strategic choices refer to com-pany purchases as corporate-level strategies, and business and marketing strategies. The empirical research was carried out in two phases and it is based on various company documents and records, and on the intensive interviews of seven key executives in the company. An abductive research design was utilized. The company gained the leading position in the kitchen market in Finland by company purchases, and the company has been able to retain the position. Firstly the goal was to expand to retail market and, secondly, the company has maintained the balance of supply and demand by closing the purchased production units when needed. The simultaneous use of these two strategic goals is a kind of a new observation, and the strategy may be suitable only for market leaders. During the latter part of the research period the strategy of com-pany purchases has been abandoned and the leading position in the market has been main-tained by developing systematically business and marketing capability. In the business and marketing strategies the distribution channels and the brands have been emphasized. During the research period the company has almost totally abandoned the long distribution channels and started to use its own channels built and named after the main brands. These are A la Carte, Parma and Petra. At the moment, in the beginning of the 21st century, a new distribution channel, the concept of the Kitchen World, is being built in addition to the channels mentioned above. The management´s decision making and the implementation the decisions have been well-considered. The executives emphasized the valuing of the importance of the decisions dif-ferently except the two decisions named the most important ones, i.e., the decisions to start own production of the raw material and to concentrate the business only to one company. The executive staff has also succeeded in managing crisis and threats of bankruptcy, and the company has been managed profitable. During all the four terms of ownership: Puolimatka Corporation, the Hankkija/Novera Corporation, the ownership period of the "bank", and the Nobia Corporate the ownership direction and control has been somewhat different. All the owners have paid attention to economic issues. The direction of cash flows and investments was at its strongest during the Hankkija/Novera term. For the last owner Nobia the production and marketing of the kitchen interiors has been the core business, which thus has strengthened the business and marketing capabilities of the target company of this research. A common denominator during all the four terms of ownership has been owners' trust gained by the professional skills of the management of the target company. This has lead to greater independence of the management of the company and less owners´ direction. Keywords: leading position, marketing strategy, management decisions, acquisition, corporate governance

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Tämän pro gradu -työn tarkoituksena on selvittää tekstin Jer 20:7-13 jumalakuvaa ja muita ”tekstin puhujan” ilmaisemia vuorovaikutussuhteita ja vaihtelevia tunteita. On kuitenkin epäselvää, missä määrin Jeremian kirja tai sen yksittäiset jaksot kuvaavat profeetan persoonaa ja historiallista taustaa. Tekstit voivat kuvata myös muita myöhempiä tilanteita ja asenteita. Tämän tutkimuksen pääasiallinen eksegeettinen metodi on syvyyspsykologinen. Se saattaa pystyä kertomaan jotakin siitä, miten tutkittava teksti peilaa menneisyyden kokemuksellisia kaavoja. Samaan tapaan kuten psykohistoriassa, tutkimus ei yritä tutkia, tulkita tai rekonstruoida tradition tai historian Jeremiaa. Syvyyspsykologinen eksegeesi on tunnistettu jo aiemmin, mutta suomalaisessa tutkimuksessa sitä ei vielä ole sovellettu yksittäisiin teksteihin. Tämän tutkimuksen tutkimusasetelma avaa tekstin sisäisiä ja vaihtelevia vuorovaikutussuhteita eli objektisuhteita. Tutkimus nimittää tätä vuorovaikutussuhteiden analyysiä objektisuhdeanalyysiksi. Se perustuu teologian tohtori, psykoanalyytikko Matti Hyrckin psykoanalyyttiseen suhteessaolon perusmielikuvien teoriaan (SPT), jonka hän esittelee väitöskirjassaan Mielen kuvat Jumalasta (1995). Tekstin Jahve-kuvat on nähtävä objektirepresentaatioina. Nämä vahvasti värittyneet representaatiot ja kuvat kertovat enemmän kokijasta itsestään kuin niistä objekteista, joiden kuviksi ne ovat syntyneet. Käsitys objektien sisäsyntyisyydestä mahdollistaa Hyrckillä objektisuhteiden systematisoinnin ja SPT:n luomisen. Siten emotionaaliset silmälasit on tämän tutkimuksen tekijän mielestä mahdollista valjastaa myös tutkijan käyttöön. Tutkimuksen laaja näkökulmia hakeva teoriaosuus varmistaa tämän. Hermeneuttinen ”kolmen maailman malli” on lukijakeskeisyyteen ja kulttuurihyppyyn arvokas työväline. Jeremian kirja sisältää useita osin runomuotoisia valituksia, joista tutkittava teksti on viimeinen. Valituslaulujen sarja päättyy tutkittavaa tekstiä seuraavaan syntymäpäivän kiroamiseen jakeissa 14-18. Valituksen edellä kontekstina on joitakin kertomuksia Jeremiasta, mutta vasta jakeessa 20:2 Jeremia nimetään profeetaksi. Muuten valittaja on nimetön. Jeremia-kertomusten kehys on tässä toimituksellinen ja valituksen jälkeen seuraa deuteronomistista saarnaa Juudaa ja Jerusalemia vastaan. Tutkimus selvittää jakeiden 7-13 rakennetta, sisältöä ja tulkintaa ensin lähinnä laji- ja kirjallisuus- kriittisesti. Tutkimus osoittaa, että Jeremian valitus noudattaa yksilön valituslaulun kaavaa, mutta ei kuitenkaan yksiselitteisesti taivu lajin usein stereotyyppisiin tarkoituksiin. Suurin syy tähän on tekstin proosa- ja runomuodon vaihtelu ja sisällön hajanaisuus. Edes valituksen ydintä ei voi varmistaa, vaikka valituslaulun nuorimpina osina on tyypillisesti helppo pitää loppupuolen kollektiivisia lisiä. Varsinainen valitus on jakeissa 7-9 ja jakeet 10-13 ovat todennäköisimmin monivaiheinen päätössarja. Tutkimuksen keskeiset objektisuhdeteoreettiset peruskäsitteet sisäinen subjekti ja sisäinen objekti ovat ihmisen tiedostamattoman tason mielikuvia. Varhaisen tilan vuorovaikutusmielikuvien sisäisinä subjekteina ovat Riippuvainen ja Itseriittoinen. Ne ovat vaihtelevissa suhteissa Houkuttajan ja Hallitsijan muotoisia sisäisiä objekteja kohtaan. Myöhäisessä tilassa objekteille on syytä antaa uudet nimet: Vetäytyjä, Vaatija ja Parantaja. Tutkimus etenee osoittamalla tekstin ja SPT:n mukaisen mallin samankaltaisuuksia. Samalla on ollut mahdollista ottaa kantaa myös tekstin saumoihin ja tekstin syntyprosessiin. Tekstin objekti osoittautuu pääosin Hallitsijaksi, sillä Houkuttajan muotoisista jumaluuksista on kollektiivisesti pyritty tekemään pesäeroa Jerusalemin temppelin hävityksestä lähtien. Silti muistoista ja Houkuttajaksikin värittyneistä kaipuun ja pelon muodoista ei päästä eroon. Valituksen alkujakeita 7-9 leimaa Riippuvaisen masennus ja Itseriittoisen häpeä. Jakeissa 11-13 Hallitsijan muotoinen Jahve Sebaot tarjoaa hierarkkista symbioosia. Myöhäistä Vaatijaa ei tutkittavassa tekstissä ole kuin vanhurskaan käsitteenä, joka deuteronomistisessa teologiassa perustuu Jahven sanan kuulemiseen ja lain noudattamiseen. Tutkimus pyrkii osoittamaan, että kaikilla kokemuksilla on jollakin tavalla sekä yhteisöä että yksilöä eheyttäviä tarkoituksia. Kun valitus päättyy sarjaan vakuutuksia ja huipentuu kollektiiviseen ylistyskehotukseen, myös niillä on tarkoitus. Yksi osa tutkimustehtävää on ollut testata psykoanalyyttisen objektisuhdeteoreettisen metodin toimivuutta eksegeettisessä tutkimuksessa. Vaikka tulokset ovat suuntaa antavia, metodi on osoittautunut toimivaksi.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Atopy-related allergic diseases, i.e. allergic rhinoconjunctivitis, atopic dermatitis and asthma, have increased in frequency in the industrialized countries. In order to reverse this trend, effective preventive strategies need to be developed. This requires a better understanding of the early-life events leading to the expression of the atopic phenotype. The present study has aimed at defining early-life factors and markers associated with the subsequent development of allergic diseases in a cohort of 200 healthy, unselected Finnish newborns prospectively followed up from birth to age 20 years. Their mothers were encouraged to start and maintain exclusive breastfeeding as long as it was nutritionally sufficient for the infant. Consequently, all the infants received some duration of exclusive breastfeeding, 58% of the infants were on exclusive breastfeeding for the first 6 months of life, and 18% received this feeding at least for the first 9 months. Of the infants, 42% had a family history of allergy. After the first year of follow-up, the children were re-assessed at ages 5, 11 and 20 years with clinical examination, skin prick testing, and parental and personal interviews. Exclusive breastfeeding for over 9 months was associated with atopic dermatitis and symptoms of food hypersensitivity at age 5 years, and with symptoms of food hypersensitivity at age 11 years in the children with a familial allergy. Subjects with allergic symptoms or a positive skin prick test in childhood or adolescence had lower retinol concentrations during their infancy and childhood than others. An elevated cord serum immunoglobulin E concentration predicted subsequent atopic manifestations though with modest sensitivity. Children and adolescents with allergic symptoms, skin prick test positivity and an elevated IgE had lower total cholesterol levels in infancy and childhood than the nonatopic subjects. In conclusion, prolonging strictly exclusive breastfeeding for over 9 months of age was not of help in prevention of allergic symptoms; instead, it was associated with increased atopic dermatitis and food hypersensitivity symptoms in childhood. Due to the modest sensitivity, cord serum IgE is not an effective screening method for atopic predisposition in the general population. Retinol and cholesterol concentrations in infancy were inversely associated with the subsequent development of allergic symptoms. Based on these findings, it is proposed that there may be differences in the inborn regulation of retinol and cholesterol levels in children with and without a genetic susceptibility to atopy, and these may play a role in the development of atopic sensitization and allergic diseases.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Alaviisaudenhampaiden poistojen harvinaisiin komplikaatioihin kuuluu alaleuanhermon vaurioituminen. Ennen poistoa panoraamakuvasta määritetään hampaan ja hermokanavan välinen etäisyys: rakenteiden kuvautuessa erilleen ei hermovaurion vaaraa katsota olevan. Tutkielman tarkoituksena oli selvittää, kuinka usein alaviisaudenhammas ja hermokanava kuvautuvat panoraamakuvassa päällekkäin, erilleen tai sivuavat toisiaan. Tutkimusaineiston panoraamakuvat on otettu Ylioppilaiden Terveydenhoitosäätiöllä Helsingissä osana normaalia hammashoitoa 20-vuotiaista (20,3±0,6 vuotta) Helsingin yliopiston opiskelijoista (N=137, naisia 71 %). Mukaan otetuissa kuvissa näkyi molemmat alaviisaudenhampaat. Panoraamakuvista mitattiin alaviisaudenhampaan etäisyys hermokanavasta millimetreinä. Tilastollisena menetelmänä käytettiin Khin-neliötestiä ja merkitsevänä erona P<0,05. Tulosten mukaan vain viidennes (19 %) alaviisaudenhampaista kuvautui erilleen hermokanavasta. Sivuavia oli 21 % ja päällekkäin kuvautuvia 60 %. Naisilla hermokanavan kanssa päällekkäin kuvautuvia hampaita oli huomattavasti enemmän kuin miehillä (65 % ja 46 %, P=0,003). Johtopäätöksenä oli, että ennen poistoa lähes kaikkien kohdalla (4/5) on pohdittava hermovaurion mahdollisuutta ja otettava potilas mukaan hoitopäätöksen tekoon. Tutkimuksen tulos on tärkeä, sillä alaviisaudenhampaita poistetaan paljon ja panoraamakuvaus on yleisin tutkimus ennen poistoja.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Julkaistu Silva Fennica Vol. 20(4) -numeron liitteenä.