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Search Results: 1 - 10 of 237 matches for " Mirella Kanerva "
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Variation of Basal EROD Activities in Ten Passerine Bird Species – Relationships with Diet and Migration Status
Miia J. Rainio, Mirella Kanerva, Niklas Wahlberg, Mikko Nikinmaa, Tapio Eeva
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0033926
Abstract: Inter-specific differences in animal defence mechanisms against toxic substances are currently poorly understood. The ethoxyresorufin-O-deethylase (EROD) enzyme plays an important role in defence against toxic chemicals in a wide variety of animals, and it is an important biomarker for environmental contamination. We compared basal hepatic EROD activity levels among ten passerine species to see if there is inter-specific variation in enzyme activity, especially in relation to their diet and migration status. Migratory insectivores showed higher EROD activity compared to granivores. We hypothesize that the variable invertebrate diet of migratory insectivores contains a wider range of natural toxins than the narrower diet of granivores. This may have affected the evolution of mixed function oxidases (MFO) system and enzyme activities. We further tested whether metabolic rates or relative liver size were associated with the variation in detoxification capacity. We found no association between EROD activity and relative (per mass unit) basal metabolic rate (BMR). Instead, EROD activity and relative liver mass (% of body mass) correlated positively, suggesting that a proportionally large liver also functions efficiently. Our results suggest that granivores and non-migratory birds may be more vulnerable to environmental contaminants than insectivores and migratory birds. The diet and migration status, however, are phylogenetically strongly connected to each other, and their roles cannot be fully separated in our analysis with only ten passerine species.
Genome-Wide Scoring of Positive and Negative Epistasis through Decomposition of Quantitative Genetic Interaction Fitness Matrices
Ville-Pekka Eronen,Rolf O. Lindén,Anna Lindroos,Mirella Kanerva,Tero Aittokallio
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0011611
Abstract: Recent technological developments in genetic screening approaches have offered the means to start exploring quantitative genotype-phenotype relationships on a large-scale. What remains unclear is the extent to which the quantitative genetic interaction datasets can distinguish the broad spectrum of interaction classes, as compared to existing information on mutation pairs associated with both positive and negative interactions, and whether the scoring of varying degrees of such epistatic effects could be improved by computational means. To address these questions, we introduce here a computational approach for improving the quantitative discrimination power encoded in the genetic interaction screening data. Our matrix approximation model decomposes the original double-mutant fitness matrix into separate components, representing variability across the array and query mutants, which can be utilized for estimating and correcting the single-mutant fitness effects, respectively. When applied to three large-scale quantitative interaction datasets in yeast, we could improve the accuracy of scoring various interaction classes beyond that obtained with the original fitness data, especially in synthetic genetic array (SGA) and in genetic interaction mapping (GIM) datasets. In addition to the known pairs of interactions used in the evaluation of the computational approach, a number of novel interaction pairs were also predicted, along with underlying biological mechanisms, which remained undetected by the original datasets. It was shown that the optimal choice of the scoring function depends heavily on the screening approach and on the interaction class under analysis. Moreover, a simple preprocessing of the fitness matrix could further enhance the discrimination power of the epistatic miniarray profiling (E-MAP) dataset. These systematic evaluation results provide in-depth information on the optimal analysis of the future, large-scale screening experiments. In general, the modeling framework, enabling accurate identification and classification of genetic interactions, provides a solid basis for completing and mining the genetic interaction networks in yeast and other organisms.
Spray-Dry Agglomerated Nanoparticles in Ordinary Portland Cement Matrix  [PDF]
Tapio Vehmas, Ulla Kanerva, Erika Holt
Materials Sciences and Applications (MSA) , 2014, DOI: 10.4236/msa.2014.512084
Abstract: Nano-sized particles have got a focus of great interest for the past decade. These ultrafine particles can have an effect in multiple ways on concrete technology. Although most of the effects of nanoparticles are desired, a huge surface area introduced by nanoparticles also incorporates negative effects, such as loss of workability and safety aspects. Agglomeration of nano-sized particles by spray-drying is one potential method to overcome the negative effects. In this study, ultra-fine material was dispersed and agglomerated successfully. Agglomerate structure was analyzed and performance was evaluated with mortar samples. Agglomerated nano-sized material had micron-sized inner porosity, which enabled water penetration into the agglomerates. In water exposure, agglomerates did not dissolve although some of binder glue and dispersing agent leaked out. Water penetration and organic material leaking enabled high reactivity and workability of the agglomerated nanoparticles. In spite of the high reactivity of agglomerated nanoparticles, slightly lower final compression strengths were observed with agglomerated ultrafine particles. The results of this study can be used in concrete technology when further developing admixture technologies and recipe designs. The negative side-effects of the agglomerated nanoparticles can be overcome and accounted for within application areas.
Mathematics and Puppet Play as a Method in the Preschool Teacher Education  [PDF]
Mirella Forsberg Ahlcrona, Ann ?stman
Creative Education (CE) , 2018, DOI: 10.4236/ce.2018.910113
Abstract: This study explores students’ perceptions and understanding of mathematics as a subject and using aesthetic expressions in their own mathematics teaching in preschool, more specifically, with puppet play as a method. In all teacher education in Sweden, mathematics in preschool?is?taught in different ways,?which means that the teaching about the aesthetic possibilities as a part of the teaching of mathematics in preschool varies. The main purpose of the study has been to investigate students’ mathematical development in preschool practice based on the changes made in the educational and methodological implications during teacher education. The data collection consists of texts from 73 students. The qualitative content analysis focuses on the students’ descriptions of understanding and meaning of mathematics and aesthetics in their own teaching with the children. The results show that the methodological implications in the courses organization and structure enabled a variation of qualitative changes in the students perceptions and beliefs about mathematics and aesthetics, but also that the conceptual languages?of mathematics could be varied and concretized by new methodological strategies.
Imbrica??es entre Goethe e Kant: Arte, Natureza e Sublime
Guidotti, Mirella;
Pandaemonium Germanicum , 2011, DOI: 10.1590/S1982-88372011000100008
Abstract: this article approaches affinities between johann wolfgang von goethe (1749-1832) and immanuel kant (1724-1804), especially regarding kant's critique of judgment. herein, this study investigates the theoretical dialogue that implicitly or explicitly permeates goethe's thought and the work of the philosopher of k?nigsberg involving concepts such as art, nature and the sublime.
A constru??o do olhar: a Viagem à Itália, de Goethe
Guidotti, Mirella;
Pandaemonium Germanicum , 2012, DOI: 10.1590/S1982-88372012000100007
Abstract: this article investigates johann wolfgang von goethe's italian journey, published in 1816-1817, which reports his travels through the italian peninsula from 1786 to 1788. more than a reconstruction of his traveling through memories and diaries, the journey stands out as a narrative of a different look towards a piece of art, as a construction of goethe's aesthetics.
Questions of Mediation in the Translation of Tourist Texts
Mirella Agorni
Altre Modernità , 2012,
Abstract: The notion of “mediation” - meant as a symbolic space for interplay and negotiation - is one on the main characteristic of the language of tourism. The force of tourism communication lies in its capacity to develop a language capable of coping with the functions and needs of the extremely diverse components of this field. Hence, a variety of discursive strategies and linguistic features are exploited and textually organised into hybrid text genres, in order to meet the needs of professionals working in several areas (transport, tourist information, tourist accommodation etc). Not only is tourism communication subject to a high degree of negotiation at textual level, but the concept of “mediation” surfaces also at the ideational level of language. The purpose of tourism is to negotiate the encounter with the Other, and in doing so identities are very often re-arranged and distorted. The object of this paper is to analyse what happens when tourism-fashioned identities are transported across linguistic, social and cultural barriers.
Language Recognition using Random Indexing
Aditya Joshi,Johan Halseth,Pentti Kanerva
Computer Science , 2014,
Abstract: Random Indexing is a simple implementation of Random Projections with a wide range of applications. It can solve a variety of problems with good accuracy without introducing much complexity. Here we use it for identifying the language of text samples. We present a novel method of generating language representation vectors using letter blocks. Further, we show that the method is easily implemented and requires little computational power and space. Experiments on a number of model parameters illustrate certain properties about high dimensional sparse vector representations of data. Proof of statistically relevant language vectors are shown through the extremely high success of various language recognition tasks. On a difficult data set of 21,000 short sentences from 21 different languages, our model performs a language recognition task and achieves 97.8% accuracy, comparable to state-of-the-art methods.
Mathematics in Preschool and Problem Solving: Visualizing Abstraction of Balance  [PDF]
Mirella Forsberg Ahlcrona, Ingrid Pramling Samuelsson
Creative Education (CE) , 2014, DOI: 10.4236/ce.2014.56052
Abstract:

This article describes how children learn to distinguish variations of the concept balance when they have different kinds of experiences of feeling, making and creating balance. The focus of the study is how children in preschool develop the ability to think logically and creative by exploring balance as phenomena in everyday life. Empirical data were collected in two preschool groups with children that were 3 - 5 years old. By following the process the results show that children and teachers increased their awareness and developed an understanding of balance, its meaning and significance, through creative teaching—by playing different games, drawing, constructing and building. The results also show that creative framework in performing activities seems to enrich the collective learning process as well as using mathematical concepts to describe the abstraction of balance.

Lysosomal storage disorders: Molecular basis and laboratory testing
Mirella Filocamo, Amelia Morrone
Human Genomics , 2011, DOI: 10.1186/1479-7364-5-3-156
Abstract: Although the first clinical descriptions of patients with lysosomal storage disorders (LSDs) were reported at the end of the nineteenth century by Warren Tay (1881)[1] and Bernard Sachs (1887; Tay-Sachs disease),[2] and by Phillipe Gaucher (1882) (Gaucher disease),[3] the biochemical nature of the accumulated products was only elucidated some 50 years later (1934) in the latter, as glucocerebroside [4]. Considerably more time was then required for the demonstration by Hers (1963) that there was a link between an enzyme deficiency and a storage disorder (Pompe disease) [5]. In the following years, the elucidation of several enzyme defects led to the initial classification of the various types of LSDs according to their clinical pictures, pathological manifestations and the biochemical nature of the undegraded substrates. Although part of this classification is still maintained, it is continually updated on the basis of newly acquired knowledge on the underlying molecular pathology.At present, more than 50 LSDs are known. The majority of these result from a deficiency of specific lysosomal enzymes. In a few cases, non-enzymatic lysosomal proteins or non-lysosomal proteins involved in lysosomal biogenesis are deficient.The common biochemical hallmark of these diseases is the accumulation of undigested metabolites in the lysosome. This can arise through several mechanisms as a result of defects in any aspect of lysosomal biology that hampers the catabolism of molecules in the lysosome, or the egress of naturally occurring molecules from the lysosome. Lysosomal accumulation activates a variety of pathogenetic cascades that result in complex clinical pictures characterised by multi-systemic involvement [6-10]. Phenotypic expression is extremely variable, as it depends on the specific macromolecule accumulated, the site of production and degradation of the specific metabolites, the residual enzymatic expression and the general genetic background of the patient. Many LSDs h
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