58 resultados para erän vaihto
Resumo:
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 The temporally earlier genotypes had been replaced by a genetically homogenous lineage that has been circulating in Europe since the late 1970s.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.
Resumo:
Double-stranded RNA (dsRNA) viruses encode only a single protein species that contains RNA-dependent RNA polymerase (RdRP) motifs. This protein is a central component in the life cycle of a dsRNA virus, carrying out both RNA transcription and replication. The architecture of viral RdRPs resembles that of a 'cupped right hand' with fingers, palm and thumb domains. Those applying de novo initiation have additional structural features, including a flexible C-terminal domain that constitutes the priming platform. Moreover, viral RdRPs must be able to interact with the incoming 3'-terminus of the template and position it so that a productive binary complex is formed. Bacteriophage phi6 of the Cystoviridae family is to date one of the best studied dsRNA viruses. The purified recombinant phi6 RdRP is highly active in vitro and possesses both RNA replication and transcription activities. The extensive biochemical observations and the atomic level crystal structure of the phi6 RdRP provides an excellent platform for in-depth studies of RNA replication in vitro. In this thesis, targeted structure-based mutagenesis, enzymatic assays and molecular mapping of phi6 RdRP and its RNA were used to elucidate the formation of productive RNA-polymerase binary complexes. The positively charged rim of the template tunnel was shown to have a significant role in the engagement of highly structured ssRNA molecules, whereas specific interactions further down in the template tunnel promote ssRNA entry to the catalytic site. This work demonstrated that by aiding the formation of a stable binary complex with optimized RNA templates, the overall polymerization activity of the phi6 RdRP can be greatly enhanced. Furthermore, proteolyzed phi6 RdRPs that possess a nick in the polypeptide chain at the hinge region, which is part of the extended loop, were better suited for catalysis at higher temperatures whilst favouring back-primed initiation. The clipped C-terminus remains associated with the main body of the polymerase and the hinge region, although structurally disordered, is involved in the control of C-terminal domain displacement. The accumulated knowhow on bacteriophage phi6 was utilized in the development of two technologies for the production of dsRNA: (i) an in vitro system that combines the T7 RNA polymerase and the phi6 RdRP to generate dsRNA molecules of practically unlimited length, and (ii) an in vivo RNA replication system based on restricted infection with phi6 polymerase complexes in bacterial cells to produce virtually unlimited amounts of dsRNA. The pools of small interfering RNAs derived from dsRNA produced by these systems were validated and shown to efficiently decrease the expression of both exogenous and endogenous targets.
Resumo:
Some leucine-rich repeat (LRR) -containing membrane proteins are known regulators of neuronal growth and synapse formation. In this work I characterize two gene families encoding neuronal LRR membrane proteins, namely the LRRTM (leucine-rich repeat, transmembrane neuronal) and NGR (Nogo-66 receptor) families. I studied LRRTM and NGR family member's mRNA tissue distribution by RT-PCR and by in situ hybridization. Subcellular localization of LRRTM1 protein was studied in neurons and in non-neuronal cells. I discovered that LRRTM and NGR family mRNAs are predominantly expressed in the nervous system, and that each gene possesses a specific expression pattern. I also established that LRRTM and NGR family mRNAs are expressed by neurons, and not by glial cells. Within neurons, LRRTM1 protein is not transported to the plasma membrane; rather it localizes to endoplasmic reticulum. Nogo-A (RTN4), MAG, and OMgp are myelin-associated proteins that bind to NgR1 to limit axonal regeneration after central nervous system injury. To better understand the functions of NgR2 and NgR3, and to explore the possible redundancy in the signaling of myelin inhibitors of neurite growth, I mapped the interactions between NgR family and the known and candidate NgR1 ligands. I identified high-affinity interactions between RTN2-66, RTN3-66 and NgR1. I also demonstrate that Rtn3 mRNA is expressed in the same glial cell population of mouse spinal cord white matter as Nogo-A mRNA, and thus it could have a role in myelin inhibition of axonal growth. To understand how NgR1 interacts with multiple structurally divergent ligands, I aimed first to map in more detail the nature of Nogo-A:NgR1 interactions, and then to systematically map the binding sites of multiple myelin ligands in NgR1 by using a library of NgR1 expression constructs encoding proteins with one or multiple surface residues mutated to alanine. My analysis of the Nogo-A:NgR1 -interactions revealed a novel interaction site between the proteins, suggesting a trivalent Nogo-A:NgR1-interaction. Our analysis also defined a central binding region on the concave side of NgR1's LRR domain that is required for the binding of all known ligands, and a surrounding region critical for binding MAG and OMgp. To better understand the biological role of LRRTMs, I generated Lrrtm1 and Lrrtm3 knock out mice. I show here that reporter genes expressed from the targeted loci can be used for maping the neuronal connections of Lrrtm1 and Lrrtm3 expressing neurons in finer detail. With regard to LRRTM1's role in humans, we found a strong association between a 70 kb-spanning haplotype in the proposed promoter region of LRRTM1 gene and two possibly related phenotypes: left-handedness and schizophrenia. Interestingly, the responsible haplotype was linked to phenotypic variability only when paternally inherited. In summary, I identified two families of neuronal receptor-like proteins, and mapped their expression and certain protein-protein interactions. The identification of a central binding region in NgR1 shared by multiple ligands may facilitate the design and development of small molecule therapeutics blocking binding of all NgR1 ligands. Additionally, the genetic association data suggests that allelic variation upstream of LRRTM1 may play a role in the development of left-right brain asymmetry in humans. Lrrtm1 and Lrrtm3 knock out mice developed as a part of this study will likely be useful for schizophrenia and Alzheimer s disease research.
Resumo:
Kohonneiden kolesterolipitoisuuksien alentamisessa käytettävien statiinien hyödyt sydän- ja verisuonisairauksien estossa on vahvasti osoitettu ja niiden käyttö on niin Suomessa kuin muuallakin maailmassa kasvanut voimakkaasti – Suomessa statiininkäyttäjiä on noin 600 000. Statiinilääkitys on pitkäaikaisessakin käytössä melko hyvin siedetty, mutta yleisimpinä haittavaikutuksina voi ilmetä lihasheikkoutta, -kipua ja -kramppeja, jotka voivat edetä jopa henkeä uhkaavaksi lihasvaurioksi. Lihashaittariski suurenee suhteessa statiiniannokseen ja plasman statiinipitoisuuksiin. Statiinien plasmapitoisuuksissa, tehossa ja haittavaikutusten ilmenemisessä on suuria potilaskohtaisia eroja. SLCO1B1-geenin koodaama OATP1B1-kuljetusproteiini kuljettaa monia elimistön omia aineita ja lääkeaineita verenkierrosta solukalvon läpi maksasoluun, mm. statiineja, joiden kolesterolia alentava vaikutus ja poistuminen elimistöstä tapahtuvat pääosin maksassa. Erään SLCO1B1-geenin nukleotidimuutoksen (c.521T>C) tiedetään heikentävän OATP1B1:n kuljetustehoa. Tässä väitöskirjatyössä selvitettiin SLCO1B1-geenin perinnöllistä muuntelua suomalaisilla ja eri väestöissä maailmanlaajuisesti. Lisäksi selvitettiin SLCO1B1:n muunnosten vaikutusta eri statiinien pitoisuuksiin (farmakokinetiikka) ja vaikutuksiin (farmakodynamiikka) sekä kolesteroliaineenvaihduntaan. Näihin tutkimuksiin valittiin SLCO1B1-genotyypin perusteella terveitä vapaaehtoisia koehenkilöitä, joille annettiin eri päivinä kerta-annos kutakin tutkittavaa statiinia: fluvastatiinia, pravastatiinia, simvastatiinia, rosuvastatiinia ja atorvastatiinia. Verinäytteistä määritettiin plasman statiinien ja niiden aineenvaihduntatuotteiden sekä kolesterolin ja sen muodostumista ja imeytymistä kuvaavien merkkiaineiden pitoisuuksia. Toiminnallisesti merkittävien SLCO1B1-geenimuunnosten esiintyvyydessä todettiin suuria eroja eri väestöjen välillä. Suomalaisilla SLCO1B1 c.521TC-genotyypin (geenimuunnos toisessa vastinkromosomissa) esiintyvyys oli noin 32 % ja SLCO1B1 c.521CC-genotyypin (geenimuunnos molemmissa vastinkromosomeissa) esiintyvyys noin 4 %. Globaalisti geenimuunnosten esiintyvyys korreloi maapallon leveyspiirien kanssa siten, että matalaan transportteriaktiivisuuteen johtavat muunnokset olivat yleisimpiä pohjoisessa ja korkeaan aktiivisuuteen johtavat päiväntasaajan lähellä asuvilla väestöillä. SLCO1B1-genotyypillä oli merkittävä vaikutus statiinien plasmapitoisuksiin lukuun ottamatta fluvastatiinia. Simvastatiinihapon plasmapitoisuudet olivat keskimäärin 220 %, atorvastatiinin 140 %, pravastatiinin 90 % ja rosuvastatiinin 70 % suuremmat c.521CC-genotyypin omaavilla koehenkilöillä verrattuna normaalin c.521TT-genotyypin omaaviin. Genotyypillä ei ollut merkittävää vaikutusta minkään statiinin tehoon tässä kerta-annostutkimuksessa, mutta geenimuunnoksen kantajilla perustason kolesterolisynteesinopeus oli suurempi. Tulokset osoittavat, että SLCO1B1 c.521T>C geenimuunnos on varsin yleinen suomalaisilla ja muilla ei-afrikkalaisilla väestöillä. Tämä geenimuunnos voi altistaa erityisesti simvastatiinin, mutta myös atorvastatiinin, pravastatiinin ja rosuvastatiinin, aiheuttamille lihashaitoille suurentamalla niiden plasmapitoisuuksia. SLCO1B1:n geenimuunnoksen testaamista voidaan tulevaisuudessa käyttää apuna valittaessa sopivaa statiinilääkitystä ja -annosta potilaalle, ja näin parantaa sekä statiinihoidon turvallisuutta että tehoa.
Resumo:
An HIV outbreak among Finnish injecting drug users (IDUs) occurred in 1998. By the end of 2005, 282 IDUs were in-fected, most of them by recombinant virus CRF01_AE of HIV. After a rapid spread, the outbreak subsided, and the prevalence of HIV among IDUs remained low (<2%). The purpose of the study was to describe the outbreak in order to recognise factors that have influenced the spread and restriction of the outbreak, and thus to find tools for HIV preven-tion. Data on Finnish IDUs newly diagnosed HIV-positive between 1998 and 2005 was collected through interviews and patient documents. Study I compared markers of disease progression between 93 Finnish IDUs and 63 Dutch IDUs. In study II, geographical spread of the HIV outbreak was examined and compared with the spatial distribution of employed males. In study III, risk behaviour data from interviews of 89 HIV-positive and 207 HIV-negative IDUs was linked, and prevalence and risk factors for unprotected sex were evaluated. In study IV, data on 238 newly diagnosed IDUs was combined with data on 675 sexually transmitted HIV cases, and risk factors for late HIV diagnosis (CD4 cell count <200/µL, or AIDS at HIV diagnosis) were analysed. Finnish IDUs infected with CRF01_AE exhibited higher viral loads than did Amsterdam IDUs infected with subtype B, but there was no difference in CD4 development. The Finnish IDU outbreak spread and was restricted socially in a marginalised IDU population and geographically in areas characterised by low proportions of employed males. Up to 40% of the cases in the two clusters outside the city centre had no contact with the centre, where needle exchange services were available since 1997. Up to 63% of HIV-positive and 80% of HIV-negative sexually active IDUs reported inconsistent condom use, which was associated with steady relationships and recent inpatient addiction care. Com-pared to other transmission groups, HIV-positive IDUs were diagnosed earlier in their infection. The proportion of late diagnosed HIV cases in all transmission groups was 23%, but was only 6% among IDUs diagnosed during the first four years of the epidemic. The high viral load in early HIV infection may have contributed to the rapid spread of recombinant virus in the Finnish outbreak. The outbreak was restricted to a marginalised IDU population, and limited spatially to local pockets of pov-erty. To prevent HIV among IDUs, these pockets should be recognised and reached early through outreach work and the distribution of needle exchange and other prevention activities. To prevent the sexual transmission of HIV among IDUs, prevention programmes should be combined with addiction care services and targeted at every IDU. The early detection of the outbreak and early implementation of needle exchange programmes likely played a crucial role in re-versing the IDU outbreak.
Resumo:
Emissions of coal combustion fly ash through real scale ElectroStatic Precipitators (ESP) were studied in different coal combustion and operation conditions. Sub-micron fly-ash aerosol emission from a power plant boiler and the ESP were determined and consequently the aerosol penetration, as based on electrical mobility measurements, thus giving thereby an indication for an estimate on the size and the maximum extent that the small particles can escape. The experimentals indicate a maximum penetration of 4% to 20 % of the small particles, as counted on number basis instead of the normally used mass basis, while simultaneously the ESP is operating at a nearly 100% collection efficiency on mass basis. Although the size range as such seems to appear independent of the coal, of the boiler or even of the device used for the emission control, the maximum penetration level on the number basis depends on the ESP operating parameters. The measured emissions were stable during stable boiler operation for a fired coal, and the emissions seemed each to be different indicating that the sub-micron size distribution of the fly-ash could be used as a specific characteristics for recognition, for instance for authenticity, provided with an indication of known stable operation. Consequently, the results on the emissions suggest an optimum particle size range for environmental monitoring in respect to the probability of finding traces from the samples. The current work embodies also an authentication system for aerosol samples for post-inspection from any macroscopic sample piece. The system can comprise newly introduced new devices, for mutually independent use, or, for use in a combination with each other, as arranged in order to promote the sampling operation length and/or the tag selection diversity. The tag for the samples can be based on naturally occurring measures and/or added measures of authenticity in a suitable combination. The method involves not only military related applications but those in civil industries as well. Alternatively to the samples, the system can be applied to ink for note printing or other monetary valued papers, but also in a filter manufacturing for marking fibrous filters.
Resumo:
There is a growing need to understand the exchange processes of momentum, heat and mass between an urban surface and the atmosphere as they affect our quality of life. Understanding the source/sink strengths as well as the mixing mechanisms of air pollutants is particularly important due to their effects on human health and climate. This work aims to improve our understanding of these surface-atmosphere interactions based on the analysis of measurements carried out in Helsinki, Finland. The vertical exchange of momentum, heat, carbon dioxide (CO2) and aerosol particle number was measured with the eddy covariance technique at the urban measurement station SMEAR III, where the concentrations of ultrafine, accumulation mode and coarse particle numbers, nitrogen oxides (NOx), carbon monoxide (CO), ozone (O3) and sulphur dioxide (SO2) were also measured. These measurements were carried out over varying measurement periods between 2004 and 2008. In addition, black carbon mass concentration was measured at the Helsinki Metropolitan Area Council site during three campaigns in 1996-2005. Thus, the analyzed dataset covered far, the most comprehensive long-term measurements of turbulent fluxes reported in the literature from urban areas. Moreover, simultaneously measured urban air pollution concentrations and turbulent fluxes were examined for the first time. The complex measurement surrounding enabled us to study the effect of different urban covers on the exchange processes from a single point of measurement. The sensible and latent heat fluxes closely followed the intensity of solar radiation, and the sensible heat flux always exceeded the latent heat flux due to anthropogenic heat emissions and the conversion of solar radiation to direct heat in urban structures. This urban heat island effect was most evident during winter nights. The effect of land use cover was seen as increased sensible heat fluxes in more built-up areas than in areas with high vegetation cover. Both aerosol particle and CO2 exchanges were largely affected by road traffic, and the highest diurnal fluxes reached 109 m-2 s-1 and 20 µmol m-2 s-1, respectively, in the direction of the road. Local road traffic had the greatest effect on ultrafine particle concentrations, whereas meteorological variables were more important for accumulation mode and coarse particle concentrations. The measurement surroundings of the SMEAR III station served as a source for both particles and CO2, except in summer, when the vegetation uptake of CO2 exceeded the anthropogenic sources in the vegetation sector in daytime, and we observed a downward median flux of 8 µmol m-2 s-1. This work improved our understanding of the interactions between an urban surface and the atmosphere in a city located at high latitudes in a semi-continental climate. The results can be utilised in urban planning, as the fraction of vegetation cover and vehicular activity were found to be the major environmental drivers affecting most of the exchange processes. However, in order to understand these exchange and mixing processes on a city scale, more measurements above various urban surfaces accompanied by numerical modelling are required.
Resumo:
For achieving efficient fusion energy production, the plasma-facing wall materials of the fusion reactor should ensure long time operation. In the next step fusion device, ITER, the first wall region facing the highest heat and particle load, i.e. the divertor area, will mainly consist of tiles based on tungsten. During the reactor operation, the tungsten material is slowly but inevitably saturated with tritium. Tritium is the relatively short-lived hydrogen isotope used in the fusion reaction. The amount of tritium retained in the wall materials should be minimized and its recycling back to the plasma must be unrestrained, otherwise it cannot be used for fueling the plasma. A very expensive and thus economically not viable solution is to replace the first walls quite often. A better solution is to heat the walls to temperatures where tritium is released. Unfortunately, the exact mechanisms of hydrogen release in tungsten are not known. In this thesis both experimental and computational methods have been used for studying the release and retention of hydrogen in tungsten. The experimental work consists of hydrogen implantations into pure polycrystalline tungsten, the determination of the hydrogen concentrations using ion beam analyses (IBA) and monitoring the out-diffused hydrogen gas with thermodesorption spectrometry (TDS) as the tungsten samples are heated at elevated temperatures. Combining IBA methods with TDS, the retained amount of hydrogen is obtained as well as the temperatures needed for the hydrogen release. With computational methods the hydrogen-defect interactions and implantation-induced irradiation damage can be examined at the atomic level. The method of multiscale modelling combines the results obtained from computational methodologies applicable at different length and time scales. Electron density functional theory calculations were used for determining the energetics of the elementary processes of hydrogen in tungsten, such as diffusivity and trapping to vacancies and surfaces. Results from the energetics of pure tungsten defects were used in the development of an classical bond-order potential for describing the tungsten defects to be used in molecular dynamics simulations. The developed potential was utilized in determination of the defect clustering and annihilation properties. These results were further employed in binary collision and rate theory calculations to determine the evolution of large defect clusters that trap hydrogen in the course of implantation. The computational results for the defect and trapped hydrogen concentrations were successfully compared with the experimental results. With the aforedescribed multiscale analysis the experimental results within this thesis and found in the literature were explained both quantitatively and qualitatively.
Resumo:
The first quarter of the 20th century witnessed a rebirth of cosmology, study of our Universe, as a field of scientific research with testable theoretical predictions. The amount of available cosmological data grew slowly from a few galaxy redshift measurements, rotation curves and local light element abundances into the first detection of the cos- mic microwave background (CMB) in 1965. By the turn of the century the amount of data exploded incorporating fields of new, exciting cosmological observables such as lensing, Lyman alpha forests, type Ia supernovae, baryon acoustic oscillations and Sunyaev-Zeldovich regions to name a few. -- CMB, the ubiquitous afterglow of the Big Bang, carries with it a wealth of cosmological information. Unfortunately, that information, delicate intensity variations, turned out hard to extract from the overall temperature. Since the first detection, it took nearly 30 years before first evidence of fluctuations on the microwave background were presented. At present, high precision cosmology is solidly based on precise measurements of the CMB anisotropy making it possible to pinpoint cosmological parameters to one-in-a-hundred level precision. The progress has made it possible to build and test models of the Universe that differ in the way the cosmos evolved some fraction of the first second since the Big Bang. -- This thesis is concerned with the high precision CMB observations. It presents three selected topics along a CMB experiment analysis pipeline. Map-making and residual noise estimation are studied using an approach called destriping. The studied approximate methods are invaluable for the large datasets of any modern CMB experiment and will undoubtedly become even more so when the next generation of experiments reach the operational stage. -- We begin with a brief overview of cosmological observations and describe the general relativistic perturbation theory. Next we discuss the map-making problem of a CMB experiment and the characterization of residual noise present in the maps. In the end, the use of modern cosmological data is presented in the study of an extended cosmological model, the correlated isocurvature fluctuations. Current available data is shown to indicate that future experiments are certainly needed to provide more information on these extra degrees of freedom. Any solid evidence of the isocurvature modes would have a considerable impact due to their power in model selection.
Resumo:
The increase in drug use and related harms in the late 1990s in Finland has come to be referred to as the second drug wave. In addition to using criminal justice as a basis of drug policy, new kinds of drug regulation were introduced. Some of the new regulation strategies were referred to as "harm reduction". The most widely known practices of harm reduction include needle and syringe exchange programmes for intravenous drug users and medicinal substitution and maintenance treatment programmes for opiate users. The purpose of the study is to examine the change of drug policy in Finland and particularly the political struggle surrounding harm reduction in the context of this change. The aim is, first, to analyse the content of harm reduction policy and the dynamics of its emergence and, second, to assess to what extent harm reduction undermines or threatens traditional drug policy. The concept of harm reduction is typically associated with a drug policy strategy that employs the public health approach and where the principal focus of regulation is on drug-related health harms and risks. On the other hand, harm reduction policy has also been given other interpretations, relating, in particular, to human rights and social equality. In Finland, harm reduction can also be seen to have its roots in criminal policy. The general conclusion of the study is that rather than posing a threat to a prohibitionist drug policy, harm reduction has come to form part of it. The implementation of harm reduction by setting up health counselling centres for drug users with the main focus on needle exchange and by extending substitution treatment has implied the creation of specialised services based on medical expertise and an increasing involvement of the medical profession in addressing drug problems. At the same time the criminal justice control of drug use has been intensified. Accordingly, harm reduction has not entailed a shift to a more liberal drug policy nor has it undermined the traditional policy with its emphasis on total drug prohibition. Instead, harm reduction in combination with a prohibitionist penal policy constitutes a new dual-track drug policy paradigm. The study draws on the constructionist tradition of research on social problems and movements, where the analysis centres on claims made about social problems, claim-makers, ways of making claims and related social mobilisation. The research material mainly consists of administrative documents and interviews with key stakeholders. The doctoral study consists of five original articles and a summary article. The first article gives an overview of the strained process of change of drug policy and policy trends around the turn of the millennium. The second article focuses on the concept of harm reduction and the international organisations and groupings involved in defining it. The third article describes the process that in 1996 97 led to the creation of the first Finnish national drug policy strategy by reconciling mutually contradictory views of addressing the drug problem, at the same as the way was paved for harm reduction measures. The fourth article seeks to explain the relatively rapid diffusion of needle exchange programmes after 1996. The fifth article assesses substitution treatment as a harm reduction measure from the viewpoint of the associations of opioid users and their family members.
Resumo:
My doctoral dissertation in sociology and Russian studies, Social Networks and Everyday Practices in Russia, employs a "micro" or "grassroots" perspective on the transition. The study is a collection of articles detailing social networks in five different contexts. The first article examines Russian birthdays from a network perspective. The second takes a look at health care to see whether networks have become obsolete in a sector that is still overwhelmingly public, but increasingly being monetarised. The third article investigates neighbourhood relations. The fourth details relationships at work, particularly from the vantage point of internal migration. The fifth explores housing and the role of networks and money both in the Soviet and post-Soviet era. The study is based on qualitative social network and interview data gathered among three groups, teachers, doctors and factory workers, in St. Petersburg during 1993-2000. Methodologically it builds on a qualitative social network approach. The study adds a critical element to the discussion on networks in post-socialism. A considerable consensus exists that social networks were vital in state socialist societies and were used to bypass various difficulties caused by endemic shortages and bureaucratic rigidities, but a more debated issue has been their role in post-socialism. Some scholars have argued that the importance of networks has been dramatically reduced in the new market economy, whereas others have stressed their continuing importance. If a common denominator in both has been a focus on networks in relation to the past, a more overlooked aspect has been the question of inequality. To what extent is access to networks unequally distributed? What are the limits and consequences of networks, for those who have access, those outside networks or society at large? My study provides some evidence about inequalities. It shows that some groups are privileged over others, for instance, middle-class people in informal access to health care. Moreover, analysing the formation of networks sheds additional light on inequalities, as it highlights the importance of migration as a mechanism of inequality, for example. The five articles focus on how networks are actually used in everyday life. The article on health care, for instance, shows that personal connections are still important and popular in post-Soviet Russia, despite the growing importance of money and the emergence of "fee for service" medicine. Fifteen of twenty teachers were involved in informal medical exchange during a two-week study period, so that they used their networks to bypass the formal market mechanisms or official procedures. Medicines were obtained through personal connections because some were unavailable at local pharmacies or because these connections could provide medicines for a cheaper price or even for free. The article on neighbours shows that "mutual help" was the central feature of neighbouring, so that the exchange of goods, services and information covered almost half the contacts with neighbours reported. Neighbours did not provide merely small-scale help but were often exchange partners because they possessed important professional qualities, had access to workplace resources, or knew somebody useful. The article on the Russian work collective details workplace-related relationships in a tractor factory and shows that interaction with and assistance from one's co-workers remains important. The most interesting finding was that co-workers were even more important to those who had migrated to the city than to those who were born there, which is explained by the specifics of Soviet migration. As a result, the workplace heavily influenced or absorbed contexts for the worker migrants to establish relationships whereas many meeting-places commonly available in Western countries were largely absent or at least did not function as trusted public meeting places to initiate relationships. More results are to be found from my dissertation: Anna-Maria Salmi: Social Networks and Everyday Practices in Russia, Kikimora Publications, 2006, see www.kikimora-publications.com.
Resumo:
Women and Marital Breakdown in South India: Reconstructing Homes, Bonds and Persons is an ethnographic analysis of the situation of divorced and separated women and their families in the South Indian city of Bangalore. The study is based on 16 months of anthropological fieldwork, i.e., participant observation and life history interviews among 50 divorced and separated women from different socio-religious backgrounds in their homes, in the women s organisations and in the Family Court. The study follows the divorced and separated women from their natal homes to their affinal homes through homelessness and legal battles to their reconstructed natal, affinal or single homes in order to find out what it means to be a person within hierarchical gender and kinship relations in South India. Marital breakdown impacts on kin relations and discloses the existing gender relations and power structure through its consequences. It makes the transformability of relational personhood as well as the transformability of relational society and culture visible. Although the study reveals the painful history of women s ill-treatment in marriage, family and kinship systems, it also demonstrates the women s rejection of the domination; and shows their ability to re-negotiate and promote changes not only to their own positions but to the whole hierarchical system as well. The study explores the divorced and separated women s manifold dilemmas, complicated legal battles, and endless arrangements when they have to struggle with the very practical problems of supporting themselves financially, finding and making a new home for themselves, and re-arranging relationships with their kin and friends. As marital breakdown fundamentally transforms the women s relational field, it forces them to recreate substitutive relations in a flexible way and, simultaneously, to re-construct themselves and their lives without a ready or positive cultural or behavioural template. This process reveals the agency of the divorced and separated women as well as shedding light on issues of gender and the cultural construction of the person in South India. This topical study explores the previously neglected subject of marital breakdown in India and shows the new meaning of kinship in South India.
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Interaction between forests and the atmosphere occurs by radiative and turbulent transport. The fluxes of energy and mass between surface and the atmosphere directly influence the properties of the lower atmosphere and in longer time scales the global climate. Boreal forest ecosystems are central in the global climate system, and its responses to human activities, because they are significant sources and sinks of greenhouse gases and of aerosol particles. The aim of the present work was to improve our understanding on the existing interplay between biologically active canopy, microenvironment and turbulent flow and quantify. In specific, the aim was to quantify the contribution of different canopy layers to whole forest fluxes. For this purpose, long-term micrometeorological and ecological measurements made in a Scots pine (Pinus sylvestris) forest at SMEAR II research station in Southern Finland were used. The properties of turbulent flow are strongly modified by the interaction between the canopy elements: momentum is efficiently absorbed in the upper layers of the canopy, mean wind speed and turbulence intensities decrease rapidly towards the forest floor and power spectra is modulated by spectral short-cut . In the relative open forest, diabatic stability above the canopy explained much of the changes in velocity statistics within the canopy except in strongly stable stratification. Large eddies, ranging from tens to hundred meters in size, were responsible for the major fraction of turbulent transport between a forest and the atmosphere. Because of this, the eddy-covariance (EC) method proved to be successful for measuring energy and mass exchange inside a forest canopy with exception of strongly stable conditions. Vertical variations of within canopy microclimate, light attenuation in particular, affect strongly the assimilation and transpiration rates. According to model simulations, assimilation rate decreases with height more rapidly than stomatal conductance (gs) and transpiration and, consequently, the vertical source-sink distributions for carbon dioxide (CO2) and water vapor (H2O) diverge. Upscaling from a shoot scale to canopy scale was found to be sensitive to chosen stomatal control description. The upscaled canopy level CO2 fluxes can vary as much as 15 % and H2O fluxes 30 % even if the gs models are calibrated against same leaf-level dataset. A pine forest has distinct overstory and understory layers, which both contribute significantly to canopy scale fluxes. The forest floor vegetation and soil accounted between 18 and 25 % of evapotranspiration and between 10 and 20 % of sensible heat exchange. Forest floor was also an important deposition surface for aerosol particles; between 10 and 35 % of dry deposition of particles within size range 10 30 nm occurred there. Because of the northern latitudes, seasonal cycle of climatic factors strongly influence the surface fluxes. Besides the seasonal constraints, partitioning of available energy to sensible and latent heat depends, through stomatal control, on the physiological state of the vegetation. In spring, available energy is consumed mainly as sensible heat and latent heat flux peaked about two months later, in July August. On the other hand, annual evapotranspiration remains rather stable over range of environmental conditions and thus any increase of accumulated radiation affects primarily the sensible heat exchange. Finally, autumn temperature had strong effect on ecosystem respiration but its influence on photosynthetic CO2 uptake was restricted by low radiation levels. Therefore, the projected autumn warming in the coming decades will presumably reduce the positive effects of earlier spring recovery in terms of carbon uptake potential of boreal forests.
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The aim of this study is to explore trust at school and its meaning for 9th grade students. The intent is to investigate students views about trust and mistrust in school relationships. Three research questions are posed: 1) what meanings do students give to their experiences of trust and mistrust at school and how do they evaluate connection of these experiences to their well-being and enjoyment in the classroom? 2) what and how important, is the teacher s role according to the students writings, and 3) what might the different pedagogical and administrative structures of schools reveal about trust and mistrust in a particular school culture? The data consists of 134 writings of 9th grade students (secondary school) from three schools in one of the biggest cities in Finland. The schools differ from others in terms of their pedagogical or structural backgrounds. The study is restricted to the micro-level of, disposition of Educational Sociology, focusing on trust in schools relationships. The theoretical framework of the study is trust, as a part of social capital; however trust is also approached from the sociological, the psychological and philosophical perspective. The methodological approach is narrative research concerning school practice . Analysis of narrative consist mostly content analysis, but also some elements of holistic-content reading, thematic reading and categorical content. The analysis found three main themes: 1) individual stories of trust, 2) the teachers role in making trust possible in the classroom, and 3) school as a community of trust. According to the study trust at school (1) is a complex phenomenon consisting of people s ability to work together and to recognize the demands that different situations present. Trust at school is often taken for granted. In the students experiences trust is strongly connected to friendship, and the teacher s ability to connect with students. Students experiences of mistrust stem from bulling, school violence, lack of respect as well as teachers lacking basic professional behavior. School relationships are important for some students as source of enjoyment, but some feel that it is difficult to evaluate the connection between trust and enjoyment. The study found that students trust of teachers (2) is linked to the teacher s professional role as a teacher, a caring human being open to dialogue. In other words, the students describe teachers abilities to create a sense of trust in terms of three expectations: the teacher was better, the same or worse than expected. Better than expected, means the teacher engender a high degree of trust and has excellent communication skills. Same as expected means the teacher comes across as familiar and secure, while lower than expected means the teacher creates no trust and has poor communication skills. Finally, it was shown that trust at school (3) should not only exist between some individuals, but between (all) members of the school community. In other words, according to the study there is some evidence that trust is strongly committed to school culture. Further, trust seems to depend on (school-) cultural background, values, beliefs, expectations, norms as well as staff behaviour. The basic elements of an optimum level of trust at school are favourable school structure and pedagogical background; however, good relationships between teachers and students as well as high professional skills are also needed. Trust at school is built by good communication, working together and getting to know each other.
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The purpose of this research was to study the bilingual class students attitudes toward schoolwork, studying in English and their attitudes toward ethnic diversity. Bilingualism has been shown to promote a person s cultural knowledge and to increase one s cultural tolerance. Also, it has been proven that young people are among the most receptive toward ethnic diversity. Students in bilingual classes have often lived abroad, travelled extensively, or have had contacts with different cultures through their parents work. This thesis seeks to clarify whether bilingualism has an effect on lower and upper graders intercultural competence. Also, it seeks to determine what the students think about their English language skills and what their abilities are to tolerate cultural differences. The research was carried out in one of Espoo Finland schools grades 4 to 9 in December 2008. One hundred fourteen (114) students participated in the research. Students answered the questions on a form where they were asked to submit their background information and answer which language they prefer in studying the school subjects. Students were also asked to choose from 18 pictures with ethnically different persons, telling which ones could be their friends and which ones they wished not to meet, as well as stating the reasons why. Also, the students answered to Likert-scale questions concerning their English studies and interculturalism. The data has been processed with qualitative and quantitative methods. The results show that the study language is not significant. Most of the students experienced studying in a bilingual class as a positive thing, and thought highly about their English skills. The students positive attitudes toward ethnic diversity and intercultural sensitivity were present in their answers. Tolerance and intercultural competence was especially noticeable in the written explanations by the older students.