Distortion of Dimension under Quasiconformal Mappings

Quasiconformal mappings are natural generalizations of conformal mappings. They are homeomorphisms with 'bounded distortion' of which there exist several approaches. In this work we study dimension distortion properties of quasiconformal mappings both in the plane and in higher dimensional Euclidean setting. The thesis consists of a summary and three research articles. A basic property of quasiconformal mappings is the local Hölder continuity. It has long been conjectured that this regularity holds at the Sobolev level (Gehring's higher integrabilty conjecture). Optimal regularity would also provide sharp bounds for the distortion of Hausdorff dimension. The higher integrability conjecture was solved in the plane by Astala in 1994 and it is still open in higher dimensions. Thus in the plane we have a precise description how Hausdorff dimension changes under quasiconformal deformations for general sets. The first two articles contribute to two remaining issues in the planar theory. The first one concerns distortion of more special sets, for rectifiable sets we expect improved bounds to hold. The second issue consists of understanding distortion of dimension on a finer level, namely on the level of Hausdorff measures. In the third article we study flatness properties of quasiconformal images of spheres in a quantitative way. These also lead to nontrivial bounds for their Hausdorff dimension even in the n-dimensional case.

Non-cellulosic cell wall polysaccharides are subject to genotype × environment effects in sorghum (Sorghum bicolor) grain

Sorghum is a staple food for half a billion people and, through growth on marginal land with minimal inputs, is an important source of feed, forage and increasingly, biofuel feedstock. Here we present information about non-cellulosic cell wall polysaccharides in a diverse set of cultivated and wild Sorghum bicolor grains. Sorghum grain contains predominantly starch (64–76) but is relatively deficient in other polysaccharides present in wheat, oats and barley. Despite overall low quantities, sorghum germplasm exhibited a remarkable range in polysaccharide amount and structure. Total (1,3;1,4)-β-glucan ranged from 0.06 to 0.43 (w/w) whilst internal cellotriose:cellotetraose ratios ranged from 1.8 to 2.9:1. Arabinoxylan amounts fell between 1.5 and 3.6 (w/w) and the arabinose:xylose ratio, denoting arabinoxylan structure, ranged from 0.95 to 1.35. The distribution of these and other cell wall polysaccharides varied across grain tissues as assessed by electron microscopy. When ten genotypes were tested across five environmental sites, genotype (G) was the dominant source of variation for both (1,3;1,4)-β-glucan and arabinoxylan content (69–74), with environment (E) responsible for 5–14. There was a small G × E effect for both polysaccharides. This study defines the amount and spatial distribution of polysaccharides and reveals a significant genetic influence on cell wall composition in sorghum grain.

Genomic deletions and mutations resulting in the loss of eight genes reduce the in vivo replication capacity of Meleagrid herpesvirus 1

Meleagrid herpesvirus 1 (MeHV-1 or turkey herpesvirus) has been widely used as a vaccine in commercial poultry. Initially, these vaccine applications were for the prevention of Marek’s disease resulting from Gallid herpesvirus 2 infections, while more recently MeHV-1 has been used as recombinant vector for other poultry infections. The construction of herpesvirus infectious clones that permit propagation and manipulation of the viral genome in bacterial hosts has advanced the studies of herpesviral genetics. The current study reports the construction of five MeHV-1 infectious clones. The in vitro properties of viruses recovered from these clones were indistinguishable from the parental MeHV-1. In contrast, the rescued MeHV-1 viruses were significantly attenuated when used in vivo. Complete sequencing of the infectious clones identified the absence of two regions of the MeHV-1 genome compared to the MeHV-1 reference sequence. These analyses determined the rescued viruses have seven genes, UL43, UL44, UL45, UL56, HVT071, sorf3 and US2 either partially or completely deleted. In addition, single nucleotide polymorphisms were identified in all clones compared with the MeHV-1 reference sequence. As a consequence of one of the polymorphisms identified in the UL13 gene, four of the rescued viruses were predicted to encode a serine/threonine protein kinase lacking two of three domains required for activity. Thus four of the recovered viruses have a total of eight missing or defective genes. The implications of these findings in the context of herpesvirus biology and infectious clone construction are discussed.

Placental infection with Ureaplasma species is associated with histologic chorioamnionitis and adverse outcomes in moderately preterm and late-preterm infants

Objective The human Ureaplasma species are the microbes most frequently isolated from placentae of women who deliver preterm. The role of Ureaplasma species has been investigated in pregnancies at <32 weeks of gestation, but currently no studies have determined the prevalence of ureaplasmas in moderately preterm and late-preterm (hereafter, “moderate/late preterm”) infants, the largest cohort of preterm infants. Methods Women delivering moderate/late preterm infants (n = 477) and their infants/placentae (n = 535) were recruited, and swab specimens of chorioamnion tissue, chorioamnion tissue specimens, and cord blood specimens were obtained at delivery. Swab and tissue specimens were cultured and analyzed by 16S ribosomal RNA polymerase chain reaction (PCR) for the presence of microorganisms, while cord blood specimens were analyzed for the presence of cytokines, chemokines, and growth factors. Results We detected microorganisms in 10.6% of 535 placentae (443 were delivered late preterm and 92 were delivered at term). Significantly, Ureaplasma species were the most prevalent microorganisms, and their presence alone was associated with histologically confirmed chorioamnionitis in moderate/late preterm and term placentae (P < .001). The presence of ureaplasmas in the chorioamnion was also associated with elevated levels of granulocyte colony-stimulating factor (P = .02). Conclusions These findings have important implications for infection and adverse pregnancy outcomes throughout gestation and should be of major consideration for obstetricians and neonatologists.

Genomic deletions and mutations resulting in the loss of eight genes reduce the in vivo replication capacity of Meleagrid herpesvirus 1

Meleagrid herpesvirus 1 (MeHV-1 or turkey herpesvirus) has been widely used as a vaccine in commercial poultry. Initially, these vaccine applications were for the prevention of Marek’s disease resulting from Gallid herpesvirus 2 infections, while more recently MeHV-1 has been used as recombinant vector for other poultry infections. The construction of herpesvirus infectious clones that permit propagation and manipulation of the viral genome in bacterial hosts has advanced the studies of herpesviral genetics. The current study reports the construction of five MeHV-1 infectious clones. The in vitro properties of viruses recovered from these clones were indistinguishable from the parental MeHV-1. In contrast, the rescued MeHV-1 viruses were significantly attenuated when used in vivo. Complete sequencing of the infectious clones identified the absence of two regions of the MeHV-1 genome compared to the MeHV-1 reference sequence. These analyses determined the rescued viruses have seven genes, UL43, UL44, UL45, UL56, HVT071, sorf3 and US2 either partially or completely deleted. In addition, single nucleotide polymorphisms were identified in all clones compared with the MeHV-1 reference sequence. As a consequence of one of the polymorphisms identified in the UL13 gene, four of the rescued viruses were predicted to encode a serine/threonine protein kinase lacking two of three domains required for activity. Thus four of the recovered viruses have a total of eight missing or defective genes. The implications of these findings in the context of herpesvirus biology and infectious clone construction are discussed.

Responses of fruit flies (Tephritidae: Dacinae) to novel male attractants in north Queensland, Australia, and improved lures for some pest species

Male fruit fly attractants, cue-lure and methyl eugenol (ME), have been successfully used for the last 50 years in the monitoring and control of Dacini fruit flies (Bactrocera and Dacus species). However, over 50% of Dacini are non-responsive to either lure, including some pest species. A new lure, zingerone, has been found to weakly attract cue- and ME-responsive species in Malaysia. In Australia it attracted a weakly cue-responsive minor pest Bactrocera jarvisi (Tryon) and three non-responsive' species. Similar compounds were tested in Queensland and attracted cue- and ME-responsive species and two non-responsive' species. In this study, 14 novel compounds, including raspberry ketone formate (RKF) (Melolure) and zingerone, were field tested in comparison with cue-lure and ME at 17 sites in north Queensland. The most attractive novel lures were isoeugenol, methyl-isoeugenol, dihydroeugenol and zingerone. Several non-responsive' species responded to the new lures: Bactrocera halfordiae (Tryon), a species of some market access concern, was most attracted to isoeugenol; B.barringtoniae (Tryon), B.bidentata (May) and B.murrayi (Perkins) responded to isoeugenol, methyl-isoeugenol and dihydroeugenol; two new species of Dacus responded to zingerone. Bactrocera kraussi (Hardy), a cue-responsive minor pest in north Queensland, was significantly more attracted to isoeugenol than cue-lure. The cue-responsive D.absonifacies (May) and D.secamoneaeDrew were significantly more attracted to zingerone than cue-lure. Bactrocera yorkensisDrew & Hancock, a ME-responsive species was significantly more attracted to isoeugenol, methyl-isoeugenol and dihydroeugenol than ME. The preferential response to RKF or cue-lure was species specific. Six species were significantly more attracted to RKF, including the pests B.tryoni (Froggatt), B.frauenfeldi (Schiner) and minor pest B.bryoniae (Tryon); eight species were significantly more attracted to cue-lure including the pest B.neohumeralis (Hardy). These findings have significance in the search for optimal male lures for pest species elsewhere in the world.

Viivesietoisten verkkojen nykytila ja tulevaisuuden haasteet

Delay and disruption tolerant networks (DTNs) are computer networks where round trip delays and error rates are high and disconnections frequent. Examples of these extreme networks are space communications, sensor networks, connecting rural villages to the Internet and even interconnecting commodity portable wireless devices and mobile phones. Basic elements of delay tolerant networks are a store-and-forward message transfer resembling traditional mail delivery, an opportunistic and intermittent routing, and an extensible cross-region resource naming service. Individual nodes of the network take an active part in routing the traffic and provide in-network data storage for application data that flows through the network. Application architecture for delay tolerant networks differs also from those used in traditional networks. It has become feasible to design applications that are network-aware and opportunistic, taking an advantage of different network connection speeds and capabilities. This might change some of the basic paradigms of network application design. DTN protocols will also support in designing applications which depend on processes to be persistent over reboots and power failures. DTN protocols could also be applicable to traditional networks in cases where high tolerance to delays or errors would be desired. It is apparent that challenged networks also challenge the traditional strictly layered model of network application design. This thesis provides an extensive introduction to delay tolerant networking concepts and applications. Most attention is given to challenging problems of routing and application architecture. Finally, future prospects of DTN applications and implementations are envisioned through recent research results and an interview with an active researcher of DTN networks.

"Politiikka on kirkossa" : Keskustapuolueen kirkkopoliittisten tavoitteiden muotoutuminen vuosina 1966–1978

This study in church history deals with the formation of aims in the church politics of the Centre Party during a period of extensive politicisation in Finnish society – 1966 to 1978. The focus is on the processes of creating political input within the party organisation. The most important source material consists of the records of the highest party organs as well as material from the party office and the party’s committee for church politics. In the late 1960s, at a time of leftist radicalism in Finnish society, issues concerning the Church were seldom dealt with in the highest party organs, even though informal discussion took place within the party. This phase was followed by a conservative reaction in society during the 1970s. The rightist trend as well as the ongoing politicisation process substantially strengthened the role of church politics in the party. An aim of great importance was to prevent those supporters who belonged to the Lutheran revival movements from moving into the Finnish Christian League. Therefore it became increasingly important to prove that the Centre Party was defending the Church as well as so-called Christian values in state politics, e.g., by advocating religious instruction in schools. The Centre Party also defended the independence and legal status of the Church, at the same time positioning itself against Finland’s Social Democratic Party. Many party members were of the opinion that the church politics should have been about defending the Church and Christian values in state politics instead of defending the proportional share of the party’s seats in the ecclesiastical decision-making system. Nevertheless, the struggle for hegemony between the Centre Party and the Social Democrats was reflected in the Evangelical Lutheran Church particularly since 1973. Thus the aims of church politics were increasingly directed towards ecclesiastical elections and appointments in the 1970s. To justify its activities in church elections, the party stressed that it was not politicising the Church. To the contrary, it was asserted that the church leaders themselves had politicised the Church by favouring the Social Democrats. These alleged efforts to affiliate the Church with one political party were strictly condemned in the Centre Party. But when it came to the political parties’ activity in church elections, opinions diverged. Generally, the issues of church politics resembled those of the party’s trade union politics in the 1970s.

Kertomuksia kirkon työntekijäksi kasvamisesta : Kirkon nuorisotyötä opiskelevien spiritualiteetin ja ammatillisen identiteetin muotoutuminen

The aim of the study was to analyse Church Youth Work Leader students different processes of developing their spirituality and professional identity. The study was carried out in connection with the church-orientated education at the Diaconia University of Applied Sciences (Diak). The method of the study was narrative analysis. The data consisted of stories written (N=46) and told (N=10) by students, that were collected over three years in two units of Diak. The data was analysed in two ways: first with categorical-content analysis, and then with holistic-content analysis and holistic-form reading in order to establish the comprehensive views of complete narratives. The theoretical starting-point was to regard spirituality widely, including religion and faith. In the first data analysis, this theory was focused so that spirituality was namely Christian spirituality including personal faith and worship, membership in the Christian community and persons values and ideas about the meaning of life. The results of the investigation were presented in five model narratives. The story of a social care worker represents the process of a student orientating to social work. In this story spirituality manifested as a part of social and personal identity but not as a part of professional identity. The vocation for helping people led the student to social care work. In the story of a counselor, students good connection to their home parish took a central role. They had good experiences working as young Christian volunteers, and during their studies this volunteer role became professional role. Spirituality was strongly joined to professional identity. The story of an educator represents a vocation for spiritual work and youth work in the church. In this story students also had good connections to their home parishes. Spirituality manifested as a part of personal, social and professional identity. In the story of a spiritual worker or preacher, each person s spiritual vocation was remarkable. Spirituality was extremely individual and it defined the personal, social and professional identity. Spiritual devotion caused a change in students orientation from the church to social services. The story of a searcher tells about a student who is still looking for her or his own profession. The focus of the story was on personal growth and considering one s values and the meaning of life. Spirituality was manifested in personal identity. The results indicate that the practical placements in the second academic year have an important effect on students professional orientation and professional identity. The connection to the local parish has also significant meaning for students spiritual formation and development into church professions.

Elements of Volatility at High Frequency

Volatility is central in options pricing and risk management. It reflects the uncertainty of investors and the inherent instability of the economy. Time series methods are among the most widely applied scientific methods to analyze and predict volatility. Very frequently sampled data contain much valuable information about the different elements of volatility and may ultimately reveal the reasons for time varying volatility. The use of such ultra-high-frequency data is common to all three essays of the dissertation. The dissertation belongs to the field of financial econometrics. The first essay uses wavelet methods to study the time-varying behavior of scaling laws and long-memory in the five-minute volatility series of Nokia on the Helsinki Stock Exchange around the burst of the IT-bubble. The essay is motivated by earlier findings which suggest that different scaling laws may apply to intraday time-scales and to larger time-scales, implying that the so-called annualized volatility depends on the data sampling frequency. The empirical results confirm the appearance of time varying long-memory and different scaling laws that, for a significant part, can be attributed to investor irrationality and to an intraday volatility periodicity called the New York effect. The findings have potentially important consequences for options pricing and risk management that commonly assume constant memory and scaling. The second essay investigates modelling the duration between trades in stock markets. Durations convoy information about investor intentions and provide an alternative view at volatility. Generalizations of standard autoregressive conditional duration (ACD) models are developed to meet needs observed in previous applications of the standard models. According to the empirical results based on data of actively traded stocks on the New York Stock Exchange and the Helsinki Stock Exchange the proposed generalization clearly outperforms the standard models and also performs well in comparison to another recently proposed alternative to the standard models. The distribution used to derive the generalization may also prove valuable in other areas of risk management. The third essay studies empirically the effect of decimalization on volatility and market microstructure noise. Decimalization refers to the change from fractional pricing to decimal pricing and it was carried out on the New York Stock Exchange in January, 2001. The methods used here are more accurate than in the earlier studies and put more weight on market microstructure. The main result is that decimalization decreased observed volatility by reducing noise variance especially for the highly active stocks. The results help risk management and market mechanism designing.

Organizational affordances: A structuration theory approach to affordances

Affordance is an important concept in the field of human–computer interaction. There are various interpretations of affordances, often extending the original notion of James J. Gibson. Often the treatment of affordances in the current human–computer interaction literature has been a one-to-one relationship between a user and an artefact. We believe that the social and cultural contexts within which an artefact is situated affect the way in which the artefact is used and the notion of affordance needs to be seen as a dynamic, always emerging relationship between people and their environment. Using a Structuration Theory approach, we conceptualize the notion of affordance at a much broader level, encompassing social and cultural aspects. We suggest that affordances should be seen at three levels: single user, organizational (or work group) and societal. Focusing on the organizational level affordances, we provide details of several important factors that affect the emergence of affordances. - This article provides a new perspective on the discourse of affordance with the use of Structuration Theory. - It shows how affordance can be understood as ‘use’ in situated practices (i.e. ‘technology-in-practice’) - The Structuration Theory approach to affordances is showcased using two case studies.

Nitrous oxide emissions from selected natural and managed northern ecosystems

Microbial activity in soils is the main source of nitrous oxide (N2O) to the atmosphere. Nitrous oxide is a strong greenhouse gas in the troposphere and participates in ozone destructive reactions in the stratosphere. The constant increase in the atmospheric concentration, as well as uncertainties in the known sources and sinks of N2O underline the need to better understand the processes and pathways of N2O in terrestrial ecosystems. This study aimed at quantifying N2O emissions from soils in northern Europe and at investigating the processes and pathways of N2O from agricultural and forest ecosystems. Emissions were measured in forest ecosystems, agricultural soils and a landfill, using the soil gradient, chamber and eddy covariance methods. Processes responsible for N2O production, and the pathways of N2O from the soil to the atmosphere, were studied in the laboratory and in the field. These ecosystems were chosen for their potential importance to the national and global budget of N2O. Laboratory experiments with boreal agricultural soils revealed that N2O production increases drastically with soil moisture content, and that the contribution of the nitrification and denitrification processes to N2O emissions depends on soil type. Laboratory study with beech (Fagus sylvatica) seedlings demonstrated that trees can serve as conduits for N2O from the soil to the atmosphere. If this mechanism is important in forest ecosystems, the current emission estimates from forest soils may underestimate the total N2O emissions from forest ecosystems. Further field and laboratory studies are needed to evaluate the importance of this mechanism in forest ecosystems. The emissions of N2O from northern forest ecosystems and a municipal landfill were highly variable in time and space. The emissions of N2O from boreal upland forest soil were among the smallest reported in the world. Despite the low emission rates, the soil gradient method revealed a clear seasonal variation in N2O production. The organic topsoil was responsible for most of the N2O production and consumption in this forest soil. Emissions from the municipal landfill were one to two orders of magnitude higher than those from agricultural soils, which are the most important source of N2O to the atmosphere. Due to their small areal coverage, landfills only contribute minimally to national N2O emissions in Finland. The eddy covariance technique was demonstrated to be useful for measuring ecosystem-scale emissions of N2O in forest and landfill ecosystems. Overall, more measurements and integration between different measurement techniques are needed to capture the large variability in N2O emissions from natural and managed northern ecosystems.

Market access and welfare: Is there a conflict?

Well known tariff reform rules that are guaranteed to increase welfare will not necessarily increase market access, while rules that are guaranteed to increase market access will not necessarily increase welfare. The present paper proposes a new set of tariff reforms that can achieve both objectives at the same time.

Measuring tax efficiency: A tax optimality index

This paper introduces an index of tax optimality that measures the distance of some current tax structure from the optimal tax structure in the presence of public goods. This index is defined on the [0, 1] interval and measures the proportion of the optimal tax rates that will achieve the same welfare outcome as some arbitrarily given initial tax structure. We call this number the Tax Optimality Index. We also show how the basic methodology can be altered to derive a revenue equivalent uniform tax, which measures the tax burden implied by the public sector. A numerical example is used to illustrate the method developed, and extensions of the analysis to handle models with multiple households and nonlinear taxation structures are undertaken.