37 resultados para Lineage Specification


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This doctoral thesis addresses the macroeconomic effects of real shocks in open economies in flexible exchange rate regimes. The first study of this thesis analyses the welfare effects of fiscal policy in a small open economy, where private and government consumption are substitutes in terms of private utility. The main findings are as follows: fiscal policy raises output, bringing it closer to its efficient level, but is not welfare-improving even though government spending directly affects private utility. The main reason for this is that the introduction of useful government spending implies a larger crowding-out effect on private consumption, when compared with the `pure waste' case. Utility decreases since one unit of government consumption yields less utility than one unit of private consumption. The second study of this thesis analyses the question of how the macroeconomic effects of fiscal policy in a small open economy depend on optimal intertemporal behaviour. The key result is that the effects of fiscal policy depend on the size of the elasticity of substitution between traded and nontraded goods. In particular, the sign of the current account response to fiscal policy depends on the interplay between the intertemporal elasticity of aggregate consumption and the elasticity of substitution between traded and nontraded goods. The third study analyses the consequences of productive government spending on the international transmission of fiscal policy. A standard result in the New Open Economy Macroeconomics literature is that a fiscal shock depreciates the exchange rate. I demonstrate that the response of the exchange rate depends on the productivity of government spending. If productivity is sufficiently high, a fiscal shock appreciates the exchange rate. It is also shown that the introduction of productive government spending increases both domestic and foreign welfare, when compared with the case where government spending is wasted. The fourth study analyses the question of how the international transmission of technology shocks depends on the specification of nominal rigidities. A growing body of empirical evidence suggests that a positive technology shock leads to a temporary decline in employment. In this study, I demonstrate that the open economy dimension can enhance the ability of sticky price models to account for the evidence. The reasoning is as follows. An improvement in technology appreciates the nominal exchange rate. Under producer-currency pricing, the exchange rate appreciation shifts global demand toward foreign goods away from domestic goods. This causes a temporary decline in domestic employment.

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This licentiate's thesis analyzes the macroeconomic effects of fiscal policy in a small open economy under a flexible exchange rate regime, assuming that the government spends exclusively on domestically produced goods. The motivation for this research comes from the observation that the literature on the new open economy macroeconomics (NOEM) has focused almost exclusively on two-country global models and the analyses of the effects of fiscal policy on small economies are almost completely ignored. This thesis aims at filling in the gap in the NOEM literature and illustrates how the macroeconomic effects of fiscal policy in a small open economy depend on the specification of preferences. The research method is to present two theoretical model that are extensions to the model contained in the Appendix to Obstfeld and Rogoff (1995). The first model analyzes the macroeconomic effects of fiscal policy, making use of a model that exploits the idea of modelling private and government consumption as substitutes in private utility. The model offers intuitive predictions on how the effects of fiscal policy depend on the marginal rate of substitution between private and government consumption. The findings illustrate that the higher the substitutability between private and government consumption, (i) the bigger is the crowding out effect on private consumption (ii) and the smaller is the positive effect on output. The welfare analysis shows that the less fiscal policy decreases welfare the higher is the marginal rate of substitution between private and government consumption. The second model of this thesis studies how the macroeconomic effects of fiscal policy depend on the elasticity of substitution between traded and nontraded goods. This model reveals that this elasticity a key variable to explain the exchange rate, current account and output response to a permanent rise in government spending. Finally, the model demonstrates that temporary changes in government spending are an effective stabilization tool when used wisely and timely in response to undesired fluctuations in output. Undesired fluctuations in output can be perfectly offset by an opposite change in government spending without causing any side-effects.

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During the past ten years, large-scale transcript analysis using microarrays has become a powerful tool to identify and predict functions for new genes. It allows simultaneous monitoring of the expression of thousands of genes and has become a routinely used tool in laboratories worldwide. Microarray analysis will, together with other functional genomics tools, take us closer to understanding the functions of all genes in genomes of living organisms. Flower development is a genetically regulated process which has mostly been studied in the traditional model species Arabidopsis thaliana, Antirrhinum majus and Petunia hybrida. The molecular mechanisms behind flower development in them are partly applicable in other plant systems. However, not all biological phenomena can be approached with just a few model systems. In order to understand and apply the knowledge to ecologically and economically important plants, other species also need to be studied. Sequencing of 17 000 ESTs from nine different cDNA libraries of the ornamental plant Gerbera hybrida made it possible to construct a cDNA microarray with 9000 probes. The probes of the microarray represent all different ESTs in the database. From the gerbera ESTs 20% were unique to gerbera while 373 were specific to the Asteraceae family of flowering plants. Gerbera has composite inflorescences with three different types of flowers that vary from each other morphologically. The marginal ray flowers are large, often pigmented and female, while the central disc flowers are smaller and more radially symmetrical perfect flowers. Intermediate trans flowers are similar to ray flowers but smaller in size. This feature together with the molecular tools applied to gerbera, make gerbera a unique system in comparison to the common model plants with only a single kind of flowers in their inflorescence. In the first part of this thesis, conditions for gerbera microarray analysis were optimised including experimental design, sample preparation and hybridization, as well as data analysis and verification. Moreover, in the first study, the flower and flower organ-specific genes were identified. After the reliability and reproducibility of the method were confirmed, the microarrays were utilized to investigate transcriptional differences between ray and disc flowers. This study revealed novel information about the morphological development as well as the transcriptional regulation of early stages of development in various flower types of gerbera. The most interesting finding was differential expression of MADS-box genes, suggesting the existence of flower type-specific regulatory complexes in the specification of different types of flowers. The gerbera microarray was further used to profile changes in expression during petal development. Gerbera ray flower petals are large, which makes them an ideal model to study organogenesis. Six different stages were compared and specifically analysed. Expression profiles of genes related to cell structure and growth implied that during stage two, cells divide, a process which is marked by expression of histones, cyclins and tubulins. Stage 4 was found to be a transition stage between cell division and expansion and by stage 6 cells had stopped division and instead underwent expansion. Interestingly, at the last analysed stage, stage 9, when cells did not grow any more, the highest number of upregulated genes was detected. The gerbera microarray is a fully-functioning tool for large-scale studies of flower development and correlation with real-time RT-PCR results show that it is also highly sensitive and reliable. Gene expression data presented here will be a source for gene expression mining or marker gene discovery in the future studies that will be performed in the Gerbera Laboratory. The publicly available data will also serve the plant research community world-wide.

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New blood cells are continuously provided by self-renewing multipotent hematopoietic stem cells (HSC). The capacity of HSCs to regenerate the hematopoietic system is utilized in the treatment of patients with hematological malignancies. HSCs can be enriched using an antibody-based recognition of CD34 or CD133 glycoproteins on the cell surface. The CD133+ and CD34+ cells may have partly different roles in hematopoiesis. Furthermore, each cell has a glycome typical for that cell type. Knowledge of HSC glycobiology can be used to design therapeutic cells with improved cell proliferation or homing properties. The present studies characterize the global gene expression profile of human cord blood-derived CD133+ and CD34+ cells, and demonstrate the differences between CD133+ and CD34+ cell populations that may have an impact in transplantation when CD133+ and CD34+ selected cells are used. In addition, these studies unravel the glycome profile of primitive hematopoietic cells and reveal the transcriptional regulation of N-glycan biosynthesis in CD133+ and CD34+ cells. The gene expression profile of CD133+ cells represents 690 differentially expressed transcripts between CD133+ cells and CD133- cells. CD34+ cells have 620 transcripts differentially expressed when compared to CD34- cells. The integrated CD133+/CD34+ cell gene expression profiles proffer novel transcripts to specify HSCs. Furthermore, the differences between the gene expression profiles of CD133+ and CD34+ cells indicate differences in the transcriptional regulation of CD133+ and CD34+ cells. CD133+ cells express a lower number of hematopoietic lineage differentiation marker genes than CD34+ cells. The expression profiles suggest a more primitive nature of CD133+ cells. Moreover, CD133+ cells have characteristic glycome that differ from the glycome of CD133- cells. High mannose-type and biantennary complex-type N-glycans are enriched in CD133+ cells. N-glycosylation-related gene expression pattern of CD133+ cells identify the key genes regulating the CD133+ cell-specific glycosylation including the overexpression of MGAT2 and underexpression of MGAT4. The putative role of MAN1C1 in the increase of unprocessed high mannose-type N-glycans in CD133+ cells is also discussed. These studies provide new information on the characteristics of HSCs. Improved understanding of HSC biology can be used to design therapeutic cells with improved cell proliferation and homing properties. As a result, HSC engineering could further their clinical use.

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This study addressed the large-scale molecular zoogeography in two brackish water bivalve molluscs, Macoma balthica and Cerastoderma glaucum, and genetic signatures of the postglacial colonization of Northern Europe by them. The traditional view poses that M. balthica in the Baltic, White and Barents seas (i.e. marginal seas) represent direct postglacial descendants of the adjacent Northeast Atlantic populations, but this has recently been challenged by observations of close genetic affinities between these marginal populations and those of the Northeast Pacific. The primary aim of the thesis was to verify, quantify and characterize the Pacific genetic contribution across North European populations of M. balthica and to resolve the phylogeographic histories of the two bivalve taxa in range-wide studies using information from mitochondrial DNA (mtDNA) and nuclear allozyme polymorphisms. The presence of recent Pacific genetic influence in M. balthica of the Baltic, White and Barents seas, along with an Atlantic element, was confirmed by mtDNA sequence data. On a broader temporal and geographical scale, altogether four independent trans-Arctic invasions of Macoma from the Pacific since the Miocene seem to have been involved in generating the current North Atlantic lineage diversity. The latest trans-Arctic invasion that affected the current Baltic, White and Barents Sea populations probably took place in the early post-glacial. The nuclear genetic compositions of these marginal sea populations are intermediate between those of pure Pacific and Atlantic subspecies. In the marginal sea populations of mixed ancestry (Barents, White and Northern Baltic seas), the Pacific and Atlantic components are now randomly associated in the genomes of individual clams, which indicates both pervasive historical interbreeding between the previously long-isolated lineages (subspecies), and current isolation of these populations from the adjacent pure Atlantic populations. These mixed populations can be characterized as self-supporting hybrid swarms, and they arguably represent the most extensive marine animal hybrid swarms so far documented. Each of the three swarms still has a distinct genetic composition, and the relative Pacific contributions vary from 30 to 90 % in local populations. This diversity highlights the potential of introgressive hybridization to rapidly give rise to new evolutionarily and ecologically significant units in the marine realm. In the south of the Danish straits and in the Southern Baltic Sea, a broad genetic transition zone links the pure North Sea subspecies M. balthica rubra to the inner Baltic hybrid swarm, which has about 60 % of Pacific contribution in its genome. This transition zone has no regular smooth clinal structure, but its populations show strong genotypic disequilibria typical of a hybrid zone maintained by the interplay of selection and gene flow by dispersing pelagic larvae. The structure of the genetic transition is partly in line with features of Baltic water circulation and salinity stratification, with greater penetration of Atlantic genes on the Baltic south coast and in deeper water populations. In all, the scenarios of historical isolation and secondary contact that arise from the phylogeographic studies of both Macoma and Cerastoderma shed light to the more general but enigmatic patterns seen in marine phylogeography, where deep genetic breaks are often seen in species with high dispersal potential.

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Multipotent stem cells can self-renew and give rise to multiple cell types. One type of mammalian multipotent stem cells are neural stem cells (NSC)s, which can generate neurons, astrocytes and oligodendrocytes. NSCs are likely involved in learning and memory, but their exact role in cognitive function in the developing and adult brain is unclear. We have studied properties of NSCs in fragile X syndrome (FXS), which is the most common form of inherited mental retardation. FXS is caused by the lack of functional fragile X mental retardation protein (FMRP). FMRP is involved in the regulation of postsynaptic protein synthesis in a group I metabotropic glutamate receptor 5 (mGluR5)-dependent manner. In the absence of functional FMRP, the formation of functional synapses is impaired in the forebrain which results in alterations in synaptic plasticity. In our studies, we found that FMRP-deficient NSCs generated more neurons and less glia than control NSCs. The newborn neurons derived from FMRP-deficient NSCs showed an abnormally immature morphology. Furthermore, FMRP-deficient NSCs exhibited aberrant oscillatory Ca2+ responses to glutamate, which were specifically abolished by an antagonist of the mGluR5 receptor. The data suggested alterations in glutamatergic differentiation of FMRP-deficient NSCs and were further supported by an accumulation of cells committed to glutamatergic lineage in the subventricular zone of the embryonic Fmr1-knockout (Fmr1-KO) neocortex. Postnatally, the aberrant cells likely contributed to abnormal formation of the neocortex. The findings suggested a defect in the differentiation of distinct glutamatergic mGluR5 responsive cells in the absence of functional FMRP. Furthermore, we found that in the early postnatal Fmr1-KO mouse brain, the expression of mRNA for regulator of G-protein signalling-4 (RGS4) was decreased which was in line with disturbed G-protein signalling in NSCs lacking FMRP. Brain derived neurotrophic factor (BDNF) promotes neuronal differentiation of NSCs as the absence of FMRP was shown to do. This led us to study the effect of impaired BDNF/TrkB receptor signaling on NSCs by overexpression of TrkB.T1 receptor isoform. We showed that changes in the relative expression levels of the full-length and truncated TrkB isoforms influenced the replication capacity of NSCs. After the differentiation, the overexpression of TrkB.T1 increased neuronal turnover. To summarize, FMRP and TrkB signaling are involved in normal differentiation of NSCs in the developing brain. Since NSCs might have potential for therapeutic interventions in a variety of neurological disorders, our findings may be useful in the design of pharmacological interventions in neurological disorders of learning and memory.

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Taxonomic relationships of the liverwort genus Herbertus in Asia were examined. In addition, the phylogeny of the family Herbertaceae and its close relatives was investigated and analyses conducted of higher level relationships within the entire liverwort phylum. Species of Herbertus show great plasticity in various morphological characters, resulted in a large number of described species. This study was the first comprehensive revision of Asian Herbertus, with 12 species recognized for the continent. Eleven names were reduced to synonymy under earlier described species, and one species was excluded from the genus. Herbertus buchii Juslén was described as a new species. Phylogenetic analyses based on both molecular and morphological characters resolved the families Vetaformaceae, Lepicoleaceae, and Herbertaceae (including Mastigophoraceae) as a monophyletic entity. This clade is among the most derived groups within the leafy liverworts and comprises mostly isophyllous plants, all of which have bracteolar antheridia. The relationships of Mastigophoraceae have formerly been controversial. My results confirm the view that this family is closely related to Herbertaceae, Lepicoleaceae, and Vetaformaceae. In the proposed new classification Mastigophoraceae is included in Herbertaceae. Phylogenetic relationships within the liverworts were reconstructed using both chloroplast and nuclear sequences as well as morphological characters. These analyses were the most comprehensive to date at the time of publication. Previously it was believed that liverworts had a common ancestor with an erect, radial gametophyte and a tetrahedral apical cell. The leafy liverworts were arranged based on the assumption that similar structures had repeatedly developed in many different suborders, with evolution proceeding from erect and isophyllous to creeping and anisophyllous plants. The complex thalloid liverworts were assumed to be the most derived group. By contrast, our studies resolved a clade comprising Treubia and Haplomitrium as the earliest extant liverwort lineage. According to our results the complex thalloids are also an early diverging lineage, and the simple thalloids, traditionally classified together, are a paraphyletic group. Within leafy liverworts, the hypothesis of repeated evolution from isophyllous to anisophyllous plants based on the assumption of a basal unresolved polytomy was rejected. Fundamentally, the leafy liverworts can be divided into three groups. In conflict with the earlier hypotheses, the isophyllous liverworts, including Herbertaceae, were resolved as derived lineages within the liverworts.

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The first part of this work investigates the molecular epidemiology of a human enterovirus (HEV), echovirus 30 (E-30). This project is part of a series of studies performed in our research team analyzing the molecular epidemiology of HEV-B viruses. A total of 129 virus strains had been isolated in different parts of Europe. The sequence analysis was performed in three different genomic regions: 420 nucleotides (nt) in the VP4/VP2 capsid protein coding region, the entire VP1 capsid protein coding gene of 876 nt, and 150 nt in the VP1/2A junction region. The analysis revealed a succession of dominant sublineages within a major genotype. The temporally earlier genotypes had been replaced by a genetically homogenous lineage that has been circulating in Europe since the late 1970s. The same genotype was found by other research groups in North America and Australia. Globally, other cocirculating genetic lineages also exist. The prevalence of a dominant genotype makes E-30 different from other previously studied HEVs, such as polioviruses and coxsackieviruses B4 and B5, for which several coexisting genetic lineages have been reported. The second part of this work deals with molecular epidemiology of human rhinoviruses (HRVs). A total of 61 field isolates were studied in the 420-nt stretch in the capsid coding region of VP4/VP2. The isolates were collected from children under two years of age in Tampere, Finland. Sequences from the clinical isolates clustered in the two previously known phylogenetic clades. Seasonal clustering was found. Also, several distinct serotype-like clusters were found to co-circulate during the same epidemic season. Reappearance of a cluster after disappearing for a season was observed. The molecular epidemiology of the analyzed strains turned out to be complex, and we decided to continue our studies of HRV. Only five previously published complete genome sequences of HRV prototype strains were available for analysis. Therefore, all designated HRV prototype strains (n=102) were sequenced in the VP4/VP2 region, and the possibility of genetic typing of HRV was evaluated. Seventy-six of the 102 prototype strains clustered in HRV genetic group A (HRV-A) and 25 in group B (HRV-B). Serotype 87 clustered separately from other HRVs with HEV species D. The field strains of HRV represented as many as 19 different genotypes, as judged with an approximate demarcation of a 20% nt difference in the VP4/VP2 region. The interserotypic differences of HRV were generally similar to those reported between different HEV serotypes (i.e. about 20%), but smaller differences, less than 10%, were also observed. Because some HRV serotypes are genetically so closely related, we suggest that the genetic typing be performed using the criterion "the closest prototype strain". This study is the first systematic genetic characterization of all known HRV prototype strains, providing a further taxonomic proposal for classification of HRV. We proposed to divide the genus Human rhinoviruses into HRV-A and HRV-B. The final part of the work comprises a phylogenetic analysis of a subset (48) of HRV prototype strains and field isolates (12) in the nonstructural part of the genome coding for the RNA-dependent RNA polymerase (3D). The proposed division of the HRV strains in the species HRV-A and HRV-B was also supported by 3D region. HRV-B clustered closer to HEV species B, C, and also to polioviruses than to HRV-A. Intraspecies variation within both HRV-A and HRV-B was greater in the 3D coding region than in the VP4/VP2 coding region, in contrast to HEV. Moreover, the diversity of HRV in 3D exceeded that of HEV. One group of HRV-A, designated HRV-A', formed a separate cluster outside other HRV-A in the 3D region. It formed a cluster also in the capsid region, but located within HRV-A. This may reflect a different evolutionary history of distinct genomic regions among HRV-A. Furthermore, the tree topology within HRV-A in the 3D region differed from that in the VP4/VP2, suggesting possible recombination events in the evolution of the strains. No conflicting phylogenies were observed in any of the 12 field isolates. Possible recombination was further studied using the Similarity and Bootscanning analyses of the complete genome sequences of HRV available in public databases. Evidence for recombination among HRV-A was found, as HRV2 and HRV39 showed higher similarity in the nonstructural part of the genome. Whether HRV2 and HRV39 strains - and perhaps also some other HRV-A strains not yet completely sequenced - are recombinants remains to be determined.

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Programed cell death (PCD) is a fundamental biological process that is as essential for the development and tissue homeostasis as cell proliferation, differentiation and adaptation. The main mode of PCD - apoptosis - occurs via specifi c pathways, such as mitochondrial or death receptor pathway. In the developing nervous system, programed death broadly occurs, mainly triggered by the defi ciency of different survival-promoting neurotrophic factors, but the respective death pathways are poorly studied. In one of the best-characterized models, sympathetic neurons deprived of nerve growth factor (NGF) die via the classical mitochondrial apoptotic pathway. The main aim of this study was to describe the death programs activated in these and other neuronal populations by using neuronal cultures deprived of other neurotrophic factors. First, this study showed that the cultured sympathetic neurons deprived of glial cell line-derived neurotrophic factor (GDNF) die via a novel non-classical death pathway, in which mitochondria and death receptors are not involved. Indeed, cytochrome c was not released into the cytosol, Bax, caspase-9, and caspase-3 were not involved, and Bcl-xL overexpression did not prevent the death. This pathway involved activation of mixed lineage kinases and c-jun, and crucially requires caspase-2 and -7. Second, it was shown that deprivation of neurotrophin-3 (NT-3) from cultured sensory neurons of the dorsal root ganglia kills them via a dependence receptor pathway, including cleavage of the NT- 3 receptor TrkC and liberation of a pro-apoptotic dependence domain. Indeed, death of NT-3-deprived neurons was blocked by a dominant-negative construct interfering with TrkC cleavage. Also, the uncleavable mutant of TrkC, replacing the siRNA-silenced endogeneous TrkC, was not able to trigger death upon NT-3 removal. Such a pathway was not activated in another subpopulation of sensory neurons deprived of NGF. Third, it was shown that cultured midbrain dopaminergic neurons deprived of GDNF or brainderived neurotrophic factor (BDNF) kills them by still a different pathway, in which death receptors and caspases, but not mitochondria, are activated. Indeed, cytochrome c was not released into the cytosol, Bax was not activated, and Bcl-xL did not block the death, but caspases were necessary for the death of these neurons. Blocking the components of the death receptor pathway - caspase-8, FADD, or Fas - blocked the death, whereas activation of Fas accelerated it. The activity of Fas in the dopaminergic neurons could be controlled by the apoptosis inhibitory molecule FAIML. For these studies we developed a novel assay to study apoptosis in the transfected dopaminergic neurons. Thus, a novel death pathway, characteristic for the dopaminergic neurons was described. The study suggests death receptors as possible targets for the treatment of Parkinson s disease, which is caused by the degeneration of dopaminergic neurons.

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This is a study of crises caused by HIV/AIDS among the Akan of Ghana. It creates more awareness about the epidemic and has indicated other possible paths for campaign strategies. The pandemic has many devastating consequences; yet new infections are recorded daily despite campaigns against the disease. The search for therapy often sees the use of multiple outlets, which expresses Ghana's pluralistic medical system based on Kleinman's sector analytical model involving Western medicine, self-therapy, and folk healing. But it also leaves individuals and kin members in financial quandary. The fieldwork for this study is mainly through participant observation lasting 13 months (February 2003 to March 2004) among the Akan; in addition, some archival materials have been used. The Akan people live in the coastal south and forest zone of Ghana. Every Akan village or town is made up of corporate lineages, and social organisation is based on matrilineal descent. The society is holistic because the matrilineages seek the welfare of all their members. Meyer Fortes, R. S. Rattray and others on the Akan noticed this encompassing nature in the lineage organisation; but they did not make it salient (or failed to notice it) during illness, efforts for healing, and the care of the sick member. HIV/AIDS is an illness which shows the encompassing nature of the Akan matrilineage. It also reveals many contradictions in the group, viz. stigmatisation, abandonment, and attitudes that do not express altruism in a group expected to be closely-knit based on members' belief that they are of the 'same blood'. The crises have been analyzed in the total social system because the disease creates breaches at various levels of social interaction. An analysis of crises in a group is not far-fetched; Victor Turner has shown the way among the Ndembu and has revealed the contraditions in the seemingly uneventful life in the group. This study has identified that in dealing with HIV/AIDS patients and crises about the disease we are dealing with 'holistic' patients. Their cases produce many changes in the matrilineal structure--many orphans are being created and the care of patients is increasingly falling on the elderly. HIV/AIDS also challenges Akan cosmology because, for example, an AIDS death in local notions is a 'bad' demise which fails to produce ancestors who reproduce the society through reincarnation. Campaigns could emphasize this notion. The study begins with a description of the holistic nature of Akan matriliny, and the patients have been described as 'holistic' because their crises affect other people in the holistic society. Chapter 2 discusses the importance of ancestors as the starting points for social order who are constantly revered (in rites invoving the chief, Chapter 4). Chapter 3 focuses on funerals as an important social performance for the welfare of the dead and the living. Chapter 5 concentrates on HIV/AIDS as an illness threat marked by dominant discourses such as poverty, sexuality, migration, and condom use. Chapter 6 analyzes the attempts for therapy, and traditional healers' claims to have a cure. The efforts for therapy continues with spiritual church healing in Chapter 7, and chapter 8 is devoted to care of the patients and its inherent crises. Chapter 9 analyzes the effects of HIV/AIDS afflictions and AIDS deaths on the matrilineal group and in society. The study ends with a short part, devoted to Recommendations based on the findings in this investigation.

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"The genetic diversity of Puumala hantavirus (PUUV) was studied in a local population of its natural host, the bank vole (Myodes glareolus). The trapping area (2.5x2.5 km) at Konnevesi, Central Finland, included 14 trapping sites, at least 500 m apart; altogether, 147 voles were captured during May and October 2005. Partial sequences of the S, M and L viral genome segments were recovered from 40 animals. Seven, 12 and 17 variants were detected for the S, M and L sequences, respectively; these represent new wild-type PUUV strains that belong to the Finnish genetic lineage. The genetic diversity of PUUV strains from Konnevesi was 0.2-4.9% for the S segment, 0.2-4.8% for the M segment and 0.2-9.7% for the L segment. Most nucleotide substitutions were synonymous and most deduced amino acid substitutions were conservative, probably due to strong stabilizing selection operating at the protein level. Based on both sequence markers and phylogenetic clustering, the S, M and L sequences could be assigned to two groups, 'A' and 'B'. Notably, not all bank voles carried S, M and L sequences belonging to the same group, i.e. SAMALA or SBMBLB.. A substantial proportion (8/40, 20%) of the newly characterized PUUV strains possessed reassortant genomes such as SBMALA, SAMBLB or SBMALB. These results suggest that at least some of the PUUV reassortants are viable and can survive in the presence of their parental strains."

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"In this study, for the first time, two distinct genetic lineages of Puumala virus (PUUV) were found within a small sampling area and within a single host genetic lineage (Ural mtDNA) at Pallasjarvi, northern Finland. Lung tissue samples of 171 bank voles (Myodes glareolus) trapped in September 1998 were screened for the presence of PUUV nucleocapsid antigen and 25 were found to be positive. Partial sequences of the PUUV small (S), medium (M) and large (L) genome segments were recovered from these samples using RT-PCR. Phylogenetic analysis revealed two genetic groups of PUUV sequences that belonged to the Finnish and north Scandinavian lineages. This presented a unique opportunity to study inter-lineage reassortment in PUUV; indeed, 32% of the studied bank voles appeared to carry reassortant virus genomes. Thus, the frequency of inter-lineage reassortment in PUUV was comparable to that of intra-lineage reassortment observed previously (Razzauti, M., Plyusnina, A., Henttonen, H. & Plyusnin, A. (2008). J Gen Virol 89, 1649-1660). Of six possible reassortant S/M/L combinations, only two were found at Pallasjarvi and, notably, in all reassortants, both S and L segments originated from the same genetic lineage, suggesting a non-random pattern for the reassortment. These findings are discussed in connection to PUUV evolution in Fermoscandia."

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This paper is concerned with using the bootstrap to obtain improved critical values for the error correction model (ECM) cointegration test in dynamic models. In the paper we investigate the effects of dynamic specification on the size and power of the ECM cointegration test with bootstrap critical values. The results from a Monte Carlo study show that the size of the bootstrap ECM cointegration test is close to the nominal significance level. We find that overspecification of the lag length results in a loss of power. Underspecification of the lag length results in size distortion. The performance of the bootstrap ECM cointegration test deteriorates if the correct lag length is not used in the ECM. The bootstrap ECM cointegration test is therefore not robust to model misspecification.

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This paper investigates the effect of income inequality on health status. A model of health status was specified in which the main variables were income level, income inequality, the level of savings and the level of education. The model was estimated using a panel data set for 44 countries covering six time periods. The results indicate that income inequality (measured by the Gini coefficient) has a significant effect on health status when we control for the levels of income, savings and education. The relationship is consistent regardless of the specification of health status and income. Thus, the study results provide some empirical support for the income inequality hypothesis.

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Over the years, a wide range of methods to verify identity have been developed. Molecular markers have been used for identification since the 1920s, commencing with blood types and culminating with the advent of DNA techniques in the 1980s. Identification is required by authorities in many occasions, e.g. in disputed paternity cases, identification of deceased, or crime investigation. To clarify maternal and paternal lineages, uniparental DNA markers in mtDNA and Y-chromosome can be utilized. These markers have several advantages: male specific Y-chromosome can be used to identify a male from a mixture of male and female cells, e.g. in rape cases. MtDNA is durable and has a high copy number, allowing analyses even from old or degraded samples. However, both markers are lineage-specific, not individualizing, and susceptible to genetic drift. Prior to the application of any DNA marker in forensic casework, it is of utmost importance to investigate its qualities and peculiarities in the target population. Earlier studies on the Finnish population have shown reduced variation in the Y-chromosome, but in mtDNA results have been ambiguous. The obtained results confirmed the low diversity in Y-chromosome in Finland. Detailed population analysis revealed large regional differences, and extremely reduced diversity especially in East Finland. Analysis of the qualities affecting Y-chromosomal short tandem repeat (Y-STR) variation and mutation frequencies, and search of new polymorphic markers resulted a set of Y-STRs with especially high diversity in Finland. Contrary to Y-chromosome, neither reduced diversity nor regional differences were found in mtDNA within Finland. In fact, mtDNA diversity was found similar to other European populations. The revealed peculiarities in the uniparental markers are a legacy of the Finnish population history. The obtained results challenge the traditional explanation which emphasizes relatively recent founder effects creating the observed east-west patterns. Uniparentally inherited markers, both mtDNA and Y-chromosome, are applicable for identification purposes in Finland. By adjusting the analysed Y marker set to meet the characteristics of Finnish population, Y-chromosomal diversity increases and the regional differentiation decreases, resulting increase in discrimination power and thus usefulness of Y-chromosomal analysis in forensic casework.