21 resultados para Intellectual and developmental difficulties


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Plant-virus interactions are very complex in nature and lead to disease and symptom formation by causing various physiological, metabolic and developmental changes in the host plants. These interactions are mainly the outcomes of viral hijacking of host components to complete their infection cycles and of host defensive responses to restrict the viral infections. Viral genomes contain only a small number of genes often encoding for multifunctional proteins, and all are essential in establishing a viral infection. Thus, it is important to understand the specific roles of individual viral genes and their contribution to the viral life cycles. Among the most important viral proteins are the suppressors of RNA silencing (VSRs). These proteins function to suppress host defenses mediated by RNA silencing and can also serve in other functions, e.g. in viral movement, transactivation of host genes, virus replication and protein processing. Thus these proteins are likely to have a significant impact on host physiology and metabolism. In the present study, I have examined the plant-virus interactions and the effects of three different VSRs on host physiology and gene expression levels by microarray analysis of transgenic plants that express these VSR genes. I also studied the gene expression changes related to the expression of the whole genome of Tobacco mosaic virus (TMV) in transgenic tobacco plants. Expression of the VSR genes in the transgenic tobacco plants causes significant changes in the gene expression profiles. HC-Pro gene derived from the Potyvirus Y (PVY) causes alteration of 748 and 332 transcripts, AC2 gene derived from the African cassava mosaic virus (ACMV) causes alteration of 1118 and 251transcripts, and P25 gene derived from the Potyvirus X (PVX) causes alterations of 1355 and 64 transcripts in leaves and flowers, respectively. All three VSRs cause similar up-regulation in defense, hormonally regulated and different stress-related genes and down-regulation in the photosynthesis and starch metabolism related genes. They also induce alterations that are specific to each viral VSR. The phenotype and transcriptome alterations of the HC-Pro expressing transgenic plants are similar to those observed in some Potyvirus-infected plants. The plants show increased protein degradation, which may be due to the HC-Pro cysteine endopeptidase and thioredoxin activities. The AC2-expressing transgenic plants show a similar phenotype and gene expression pattern as HC-Pro-expressing plants, but also alter pathways related to jasmonic acid, ethylene and retrograde signaling. In the P25 expressing transgenic plants, high numbers of genes (total of 1355) were up-regulated in the leaves, compared to a very low number of down-regulated genes (total of 5). Despite of strong induction of the transcripts, only mild growth reduction and no other distinct phenotype was observed in these plants. As an example of whole virus interactions with its host, I also studied gene expression changes caused by Tobacco mosaic virus (TMV) in tobacco host in three different conditions, i.e. in transgenic plants that are first resistant to the virus, and then become susceptible to it and in wild type plants naturally infected with this virus. The microarray analysis revealed up and down-regulation of 1362 and 1422 transcripts in the TMV resistant young transgenic plants, and up and down-regulation of a total of 1150 and 1200 transcripts, respectively, in the older plants, after the resistance break. Natural TMV infections in wild type plants caused up-regulation of 550 transcripts and down-regulation of 480 transcripts. 124 up-regulated and 29 down-regulated transcripts were commonly altered between young and old TMV transgenic plants, and only 6 up-regulated and none of the down-regulated transcripts were commonly altered in all three plants. During the resistant stage, the strong down-regulation in translation-related transcripts (total of 750 genes) was observed. Additionally, transcripts related to the hormones, protein degradation and defense pathways, cell division and stress were distinctly altered. All these alterations may contribute to the TMV resistance in the young transgenic plants, and the resistance may also be related to RNA silencing, despite of the low viral abundance and lack of viral siRNAs or TMV methylation activity in the plants.

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Reports have shown that a growing number of students are leaving school without adequate reading and writing skills. At the same time, finnish children have improved in reading lit-eracy over the past decade. The school´s primary mission is to support student´s reading and writing development and follow it over time. Not only individual students´development has to be followd over time, as seen in this study, to be able to plan interventions. The purpose of this licentiate thesis is to study how the results in grades 1–6 exhibit in reading compre-hension and spelling over time in a school for the Swedish-speaking minority in Finland. Even gender differences in reading comprehension and spelling are being examined, as well as students with low performance. The data collection has been done during a period of twelwe years, 1997–2009, where data from practically every two years has been used for this study. Results are reported for the years 1997, 2000, 2001, 2003, 2007 and 2009. The measuring instruments are standardized and normative tests in reading comprehension and spelling. The same instruments were used all of the years. The number of students was 1 037 and when possible, students partici-pated more than once. There was a minimal loss of data. The groups of students mostly came from urban districts, and a smaller number came from rural districts. Students with special needs were included in the group, but none of the students in special units participat-ed. The results show that the skills in reading comprehension and spelling haven´t changed appreciably over time. The trend shows slightly positive or unchanged direction except in spelling in grade 1 and reading comprehension in grade 5 where the trend is slightly nega-tive. The most obvious change can be noticed over time in reading comprehension in grade 2, where performance has improved significantly. Significant differences between boys´and girls´performances occur some years and in favor of the girls, but more often in spelling than in reading comprehension. In grade 4, there are no differences in results between boys and girls in any year, neither in reading comprehension nor in spelling, nor in grade 2 in reading comprehension. When the results shows gender differences, there are always differ-ences in both reading comprehension and spelling. Poor performances are also analyzed over time. Isolated reading comprehension difficulties were common for those who was performing poorly. In grade 2, as the only grade, most common was a double deficit in both reading comprehension and spelling, and in grade 4, most students who performed poorly had isolated difficulties in spelling. The amount of poor results varies over time, and no particular trend can be discerned. In grade 2, however, the poor results decreased over time, especially for the boys. Even in reading comprehension for grade 6 the amount of poor results, especially for the boys (10th percentile), has decreased over time, at least in the later years, while the poor results in-creased in spelling generally. In grade 4 the amount of poor results in spelling (10th perc.) seems to be reduced for the girls.

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This applied linguistic study in the field of second language acquisition investigated the assessment practices of class teachers as well as the challenges and visions of language assessment in bilingual content instruction (CLIL) at primary level in Finnish basic education. Furthermore, pupils’ and their parents’ perceptions of language assessment and LangPerform computer simulations as an alternative, modern assessment method in CLIL contexts were examined. The study was conducted for descriptive and developmental purposes in three phases: 1) a CLIL assessment survey; 2) simulation 1; and 3) simulation 2. All phases had a varying number of participants. The population of this mixed methods study were CLIL class teachers, their pupils and the pupils’ parents. The sampling was multi-staged and based on probability and random sampling. The data were triangulated. Altogether 42 CLIL class teachers nationwide, 109 pupils from the 3rd, 4th and 5th grade as well as 99 parents from two research schools in South-Western Finland participated in the CLIL assessment survey followed by an audio-recorded theme interview of volunteers (10 teachers, 20 pupils and 7 parents). The simulation experimentations 1 and 2 produced 146 pupil and 39 parental questionnaires as well as video interviews of volunteered pupils. The data were analysed both quantitatively using percentages and numerical frequencies and qualitatively employing thematic content analysis. Based on the data, language assessment in primary CLIL is not an established practice. It largely appears to be infrequent, incidental, implicit and based on impressions rather than evidence or the curriculum. The most used assessment methods were teacher observation, bilingual tests and dialogic interaction, and the least used were portfolios, simulations and peer assessment. Although language assessment was generally perceived as important by teachers, a fifth of them did not gather assessment information systematically, and 38% scarcely gave linguistic feedback to pupils. Both pupils and parents wished to receive more information on CLIL language issues; 91% of pupils claimed to receive feedback rarely or occasionally, and 63% of them wished to get more information on their linguistic coping in CLIL subjects. Of the parents, 76% wished to receive more information on the English proficiency of their children and their linguistic development. This may be a response to indirect feedback practices identified in this study. There are several challenges related to assessment; the most notable is the lack of a CLIL curriculum, language objectives and common ground principles of assessment. Three diverse approaches to language in CLIL that appear to affect teachers’ views on language assessment were identified: instrumental (language as a tool), dual (language as a tool and object of learning) and eclectic (miscellaneous views, e.g. affective factors prioritised). LangPerform computer simulations seem to be perceived as an appropriate alternative assessment method in CLIL. It is strongly recommended that the fundamentals for assessment (curricula and language objectives) and a mutual assessment scheme should be determined and stakeholders’ knowledge base of CLIL strengthened. The principles of adequate assessment in primary CLIL are identified as well as several appropriate assessment methods suggested.

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Tämän tutkielman tavoitteena oli selvittää, mitä mahdollisuuksia ja haasteita sähköinen taloushallinto tuo tilitoimistoille ja miten ne vaikuttavat työskentelyyn. Vaikka sähköisiä taloushallinnon järjestelmiä on tutkittu paljon jo aiemmin, vielä ei kovin laajasti ole tarkasteltu sitä, miten ne käytännössä vaikuttavat tilitoimistoihin. Tutkielma on luonteeltaan kvalitatiivinen ja se on toteutettu case-tutkimuksena lappeenrantalaisesta tilitoimistosta. Tutkimuksen teoria rakentuu aihetta käsittelevän kirjallisuuden perusteella ja empiria on kerätty puolistrukturoiduilla teemahaastatteluilla. Haastatteluista saatuja tuloksia on verrattu kirjallisuudessa esitettyihin näkemyksiin sähköisen taloushallinnon mahdollisuuksista ja haasteista sekä sähköisen taloushallinnon vaikutuksista työskentelyyn. Tutkimuksessa selvisi, että kirjallisuudessa ja käytännössä sähköisen taloushallinnon tarjoamat mahdollisuudet ja haasteet sekä niiden vaikutukset työskentelyyn eroavat toisistaan. Suurimpia mahdollisuuksia olivat työskentelyn parantunut tehokkuus, kustannussäästöt sekä saadun informaation parempi laatu. Teoriassa haasteiksi koettiin koulutuksen puute ja työntekijöiden sekä asiakkaiden muutosvastarinta. Käytännössä suurimman haasteen sähköisen taloushallinnon käytettävyydelle kuitenkin aiheuttavat ohjelmistot ja niiden mukanaan tuomat ongelmat. Sähköistymisen myötä kirjanpitäjistä tulee teoriassa enemmänkin konsultteja ja tilitoimistoissakin työskentelee erikseen esimerkiksi reskontranhoitajia. Tosiasiassa roolien muuttuminen ei kuitenkaan ole aivan itsestään selvää ja sähköisiin järjestelmiin siirtymisen odotetaan kestävän vielä kauan.

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This study is based on a large survey study of over 1500 Finnish companies’ usage, needs and implementation difficulties of management accounting systems. The study uses quantitative, qualitative and mixed methods to answer the research questions. The empirical data used in the study was gathered through structured interviews with randomly selected companies of varying sizes and industries. The study answers the three research questions by analyzing the characteristics and behaviors of companies working in Finland. The study found five distinctive groups of companies according to the characteristics of their cost information and management accounting system use. The study also showed that the state of cost information and management accounting systems depends on the industry and size of the companies. It was found that over 50% of the companies either did not know how their systems could be updated or saw systems as inadequate. The qualitative side also highlighted the needs for tailored and integrated management accounting systems for creating more value to the managers of companies. The major inhibitors of new system implementation were the lack of both monetary and human resources. Through the use of mixed methods and design science a new and improved sophistication model is created based on previous research results combined with the information gathered from previous literature. The sophistication model shows the different stages of management accounting systems in use and what companies can achieve with the implementation and upgrading of their systems.

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This study aims to extend prior knowledge on the learning and developmental outcomes of the experiential learning cycle of David Kolb by the analysis of its practical realization at Team Academy. The study is based on the constructivist approach to learning and considers, among others, the concepts of autonomy support, Nonaka and Takeuchi's knowledge creation model, Luft and Ingham's Johari Window and Deci and Ryan's Self-determination theory. For the investigation deep interviews were carried out with the participants of Team Academy, both learners and coaches. Taking the interview results and the above described theories into consideration this study concludes that experiential learning results not only in effective learning, but also in a remarkable soft skill acquisition, self-development and increase in motivation with an internal locus of causality. Real-life projects permit the learners to experience real challenges. By the practical activities and teamwork they also get the possibility to find out their personal strengths, weaknesses and unique capacities.