960 resultados para 3T MRI


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Conventional invasive coronary angiography is the clinical gold standard for detecting of coronary artery stenoses. Noninvasive multidetector computed tomography (MDCT) in combination with retrospective ECG gating has recently been shown to permit visualization of the coronary artery lumen and detection of coronary artery stenoses. Single photon emission tomography (SPECT) perfusion imaging has been considered the reference method for evaluation of nonviable myocardium, but magnetic resonance imaging (MRI) can accurately depict structure, function, effusion, and myocardial viability, with an overall capacity unmatched by any other single imaging modality. Magnetocardiography (MCG) provides noninvasively information about myocardial excitation propagation and repolarization without the use of electrodes. This evolving technique may be considered the magnetic equivalent to electrocardiography. The aim of the present series of studies was to evaluate changes in the myocardium assessed with SPECT and MRI caused by coronary artery disease, examine the capability of multidetector computed tomography coronary angiography (MDCT-CA) to detect significant stenoses in the coronary arteries, and MCG to assess remote myocardial infarctions. Our study showed that in severe, progressing coronary artery disease laser treatment does not improve global left ventricular function or myocardial perfusion, but it does preserve systolic wall thickening in fixed defects (scar). It also prevents changes from ischemic myocardial regions to scar. The MCG repolarization variables are informative in remote myocardial infarction, and may perform as well as the conventional QRS criteria in detection of healed myocardial infarction. These STT abnormalities are more pronounced in patients with Q-wave infarction than in patients with non-Q-wave infarctions. MDCT-CA had a sensitivity of 82%, a specificity of 94%, a positive predictive value of 79%, and a negative predictive value of 95% for stenoses over 50% in the main coronary arteries as compared with conventional coronary angiography in patients with known coronary artery disease. Left ventricular wall dysfunction, perfusion defects, and infarctions were detected in 50-78% of sectors assigned to calcifications or stenoses, but also in sectors supplied by normally perfused coronary arteries. Our study showed a low sensitivity (sensitivity 63%) in detecting obstructive coronary artery disease assessed by MDCT in patients with severe aortic stenosis. Massive calcifications complicated correct assessment of the lumen of coronary arteries.

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Painful bladder syndrome/interstitial cystitis (PBS/IC) is a chronic urinary bladder disorder of unknown etiology characterized by symptoms of bladder pain and urinary frequency. PBS/IC is a chronic disease in which drug therapy has not led to significant success over the course of time. If the symptoms of PBS/IC are refractory to standard treatments, a possible cure might demand surgical intervention involving cystectomy. The eventual autoimmune etiology in mind, immunosuppressive drug therapy with cyclosporine A (CyA) was started to patients with refractory PBS/IC. CyA is a potent anti-inflammatory drug, a calcineurin inhibitor which inhibits T lymphocyte IL-2 produc-tion. T cells are present in abundance in inflammation of the bladder in PBS/IC. On the basis of a pilot, short-term study with CyA on PBS/IC, use of CyA was continued empirically over the long term. We conducted a prospective, randomized, six-month study in 64 patients comparing the effect of CyA with the FDA approved treatment, pentosan polysulfate sodium (PPS). We measured the drug effect on patient s symptoms, the potassium sensitivity test, and on urinary biomarkers. We further tested the impact of CyA, PPS, DMSO and BCG therapy on a health-related quality of life questionnaire and evaluated the response rate to treatment with these therapies. Long-term use of CyA was safe and effective in PBS/IC patients. The good clinical effect matured individually during the years in which CyA was continued. Cessation of medication led to the reappearance of symptoms, and restarting CyA to renewed alleviation, so that CyA was administered as continuous medication. The response rate to CyA increased during the study period, comprising 75% of CyA patients at six months. 19% of patients responded to PPS therapy. Adverse effects were more common in the CyA group, underlining the importance of monitoring the drug safety and appropriate titration of the dose. The potassium sensitivity test is positive in the majority of PBS/IC patients. Successful therapy of PBS/IC can alter nerve sensitivity to external potassium. This effect was seen more often after CyA therapy. Successful treatment of PBS/IC with CyA resulted to decreasing urinary levels of EGF. IL-6 levels in urine were higher among older patient with a longer history of PBS/IC. In these patients, reduced levels of urinary IL-6 were measured after CyA therapy. Patients who experience the best treatment response have improved quality of life according to the post-treatment health-related quality of life (HRQOL) questionnaire. CyA had more impact on the ma-jority of the aspects of QoL than PPS. Despite DMSO therapy being more successful than BCG in the count of responders, DMSO and BCG had equal effects on the HRQOL questionnaire.

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A low temperature polyol process, based on glycolaldehyde mediated partial reduction of FeCl3 center dot 6H(2)O at 120 degrees C in the presence of sodium acetate as an alkali source and 2,2'-(ethylenedioxy)-bis-(ethylamine) as an electrostatic stabilizer has been used for the gram-scale preparation of biocompatible, water-dispersible, amine functionalized magnetite nanoparticles (MNPs) with an average diameter of 6 +/- 0.75 nm. With a reasonably high magnetization (37.8 e.m.u.) and amine groups on the outer surface of the nanoparticles, we demonstrated the magnetic separation and concentration implications of these ultrasmall particles in immunoassay. MRI studies indicated that these nanoparticles had the desired relaxivity for T-2 contrast enhancement in vivo. In vitro biocompatibility, cell uptake and MR imaging studies established that these nanoparticles were safe in clinical dosages and by virtue of their ultrasmall sizes and positively charged surfaces could be easily internalized by cancer cells. All these positive attributes make these functional nanoparticles a promising platform for further in vitro and in vivo evaluations.

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Heart failure is a common and highly challenging medical disorder. The progressive increase of elderly population is expected to further reflect in heart failure incidence. Recent progress in cell transplantation therapy has provided a conceptual alternative for treatment of heart failure. Despite improved medical treatment and operative possibilities, end-stage coronary artery disease present a great medical challenge. It has been estimated that therapeutic angiogenesis would be the next major advance in the treatment of ischaemic heart disease. Gene transfer to augment neovascularization could be beneficial for such patients. We employed a porcine model to evaluate the angiogenic effect of vascular endothelial growth factor (VEGF)-C gene transfer. Ameroid-generated myocardial ischemia was produced and adenovirus encoding (ad)VEGF-C or β-galactosidase (LacZ) gene therapy was given intramyocardially during progressive coronary stenosis. Angiography, positron emission tomography (PET), single photon emission computed tomography (SPECT) and histology evidenced beneficial affects of the adVEGF-C gene transfer compared to adLacZ. The myocardial deterioration during progressive coronary stenosis seen in the control group was restrained in the treatment group. We observed an uneven occlusion rate of the coronary vessels with Ameroid constrictor. We developed a simple methodological improvement of Ameroid model by ligating of the Ameroid–stenosed coronary vessel. Improvement of the model was seen by a more reliable occlusion rate of the vessel concerned and a formation of a rather constant myocardial infarction. We assessed the spontaneous healing of the left ventricle (LV) in this new model by SPECT, PET, MRI, and angiography. Significant spontaneous improvement of myocardial perfusion and function was seen as well as diminishment of scar volume. Histologically more microvessels were seen in the border area of the lesion. Double staining of the myocytes in mitosis indicated more cardiomyocyte regeneration at the remote area of the lesion. The potential of autologous myoblast transplantation after ischaemia and infarction of porcine heart was evaluated. After ligation of stenosed coronary artery, autologous myoblast transplantation or control medium was directly injected into the myocardium at the lesion area. Assessed by MRI, improvement of diastolic function was seen in the myoblast-transplanted animals, but not in the control animals. Systolic function remained unchanged in both groups.

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Cardiovascular diseases (CVD) are, in developed countries, the leading cause of mortality. The majority of premature deaths and disability caused by CVD are due to atherosclerosis, a degenerating inflammatory disease affecting arterial walls. Early identification of lesions and initiation of treatment is crucial because the first manifestations quite often are major disabling cardiovascular events. Methods of finding individuals at high risk for these events are under development. Because magnetic resonance imaging (MRI) is an excellent non-invasive tool to study the structure and function of vascular system, we sought to discover whether existing MRI methods are able to show any difference in aortic and intracranial atherosclerotic lesions between patients at high risk for atherosclerosis and healthy controls. Our younger group (age 6-48) comprised 39 symptomless familial hypercholesterolemia (FH) patients and 25 healthy controls. Our older group (age 48-64) comprised 19 FH patients and 18 type 2 diabetes mellitus (DM) patients with coronary heart disease (CHD) and 29 healthy controls. Intracranial and aortic MRI was compared with carotid and femoral ultrasound (US). In neither age-group did MRI reveal any difference in the number of ischemic brain lesions or white matter hyperintensities (WMHIs) - possible signs of intracranial atherosclerosis - between patients and controls. Furthermore, MRI showed no difference in the structure or function of the aorta between FH patients and controls in either group. DM patients had lower compliance of the aorta than did controls, while no difference appeared between DM and FH patients. However, ultrasound showed greater plaque burden and increased thickness of carotid arterial walls in FH and DM patients in both age-groups, suggesting a more advanced atherosclerosis. The mortality of FH patients has decreased substantially after the late 1980´s when statin treatment became available. With statins, the progression of atherosclerotic lesions slows. We think that this, in concert with improvements in treatment of other risk factors, is one reason for the lack of differences between FH patients and controls in MRI measurements of the aorta and brain despite the more advanced disease of the carotid arteries assessed with US. Furthermore, whereas atherosclerotic lesions between different vascular territories correlate, differences might still exist in the extent and location of these lesions among different diseases. Small (<5 mm in diameter) WMHIs are more likely a phenomenon related to aging, but the larger ones may be the ones related to CVD and may be intermediate surrogates of stroke. The image quality in aortic imaging, although constantly improving, is not yet optimal and thus is a source of bias.

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A conventional magnesium alloy, AZ91D, and two creep resistant magnesium alloys, developed for powertrain applications, MRI 153M and MRI 230D, are prepared by high pressure die casting. These alloys are tested for their creep behaviour in the continuous manner, as is the Current practice, and in the interrupted manner, which represents the real life Situation more closely. It is observed that the interrupted creep tests give rise to a primary creep appearing at the beginning of each cycle resulting in a higher average strain rate than that encountered in the continuous creep tests. Further, the shorter the cycle time, higher is the average strain rate in the interrupted creep tests. A higher average strain rate will give rise to a higher strain over the same period. This is attributed to the recovery taking place during the cooling and heating between two cycles. The effect of additional precipitation during interrupted creep tests depends on the nature of the precipitates. The additional precipitation of beta phase during the cooling and heating between two cycles increases the steady state strain rate in the AZ91D and MRI 153M alloys. whereas the additional precipitation of C36 phase during the cooling and heating between two cycles decreases the steady state strain rate in the MRI 230D alloy. (C) 2009 Elsevier B.V. All rights reserved.

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Acute knee injury is a common event throughout life, and it is usually the result of a traffic accident, simple fall, or twisting injury. Over 90% of patients with acute knee injury undergo radiography. An overlooked fracture or delayed diagnosis can lead to poor patient outcome. The major aim of this thesis was retrospectively to study imaging of knee injury with a special focus on tibial plateau fractures in patients referred to a level-one trauma center. Multi-detector computed tomography (MDCT) findings of acute knee trauma were studied and compared to radiography, as well as whether non-contrast MDCT can detect cruciate ligaments with reasonable accuracy. The prevalence, type, and location of meniscal injuries in magnetic resonance imaging (MRI) were evaluated, particularly in order to assess the prevalence of unstable meniscal tears in acute knee trauma with tibial plateau fractures. The possibility to analyze with conventional MRI the signal appearance of menisci repaired with bioabsorbable arrows was also studied. The postoperative use of MDCT was studied in surgically treated tibial plateau fractures: to establish the frequency and indications of MDCT and to assess the common findings and their clinical impact in a level-one trauma hospital. This thesis focused on MDCT and MRI of knee injuries, and radiographs were analyzed when applica-ble. Radiography constitutes the basis for imaging acute knee injury, but MDCT can yield information beyond the capabilities of radiography. Especially in severely injured patients , sufficient radiographs are often difficult to obtain, and in those patients, radiography is unreliable to rule out fractures. MDCT detected intact cruciate ligaments with good specificity, accuracy, and negative predictive value, but the assessment of torn ligaments was unreliable. A total of 36% (14/39) patients with tibial plateau fracture had an unstable meniscal tear in MRI. When a meniscal tear is properly detected preoperatively, treatment can be combined with primary fracture fixation, thus avoiding another operation. The number of meniscal contusions was high. Awareness of the imaging features of this meniscal abnormality can help radiologists increase specificity by avoiding false-positive findings in meniscal tears. Postoperative menisci treated with bioabsorbable arrows showed no difference, among different signal intensities in MRI, among menisci between patients with operated or intact ACL. The highest incidence of menisci with an increased signal intensity extending to the meniscal surface was in patients whose surgery was within the previous 18 months. The results may indicate that a rather long time is necessary for menisci to heal completely after arrow repair. Whether the menisci with an increased signal intensity extending to the meniscal surface represent improper healing or re-tear, or whether this is just the earlier healing feature in the natural process remains unclear, and further prospective studies are needed to clarify this. Postoperative use of MDCT in tibial plateau fractures was rather infrequent even in this large trauma center, but when performed, it revealed clinically significant information, thus benefitting patients in regard to treatment.

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Nucleation is the first step of the process by which gas molecules in the atmosphere condense to form liquid or solid particles. Despite the importance of atmospheric new-particle formation for both climate and health-related issues, little information exists on its precise molecular-level mechanisms. In this thesis, potential nucleation mechanisms involving sulfuric acid together with either water and ammonia or reactive biogenic molecules are studied using quantum chemical methods. Quantum chemistry calculations are based on the numerical solution of Schrödinger's equation for a system of atoms and electrons subject to various sets of approximations, the precise details of which give rise to a large number of model chemistries. A comparison of several different model chemistries indicates that the computational method must be chosen with care if accurate results for sulfuric acid - water - ammonia clusters are desired. Specifically, binding energies are incorrectly predicted by some popular density functionals, and vibrational anharmonicity must be accounted for if quantitatively reliable formation free energies are desired. The calculations reported in this thesis show that a combination of different high-level energy corrections and advanced thermochemical analysis can quantitatively replicate experimental results concerning the hydration of sulfuric acid. The role of ammonia in sulfuric acid - water nucleation was revealed by a series of calculations on molecular clusters of increasing size with respect to all three co-ordinates; sulfuric acid, water and ammonia. As indicated by experimental measurements, ammonia significantly assists the growth of clusters in the sulfuric acid - co-ordinate. The calculations presented in this thesis predict that in atmospheric conditions, this effect becomes important as the number of acid molecules increases from two to three. On the other hand, small molecular clusters are unlikely to contain more than one ammonia molecule per sulfuric acid. This implies that the average NH3:H2SO4 mole ratio of small molecular clusters in atmospheric conditions is likely to be between 1:3 and 1:1. Calculations on charged clusters confirm the experimental result that the HSO4- ion is much more strongly hydrated than neutral sulfuric acid. Preliminary calculations on HSO4- NH3 clusters indicate that ammonia is likely to play at most a minor role in ion-induced nucleation in the sulfuric acid - water system. Calculations of thermodynamic and kinetic parameters for the reaction of stabilized Criegee Intermediates with sulfuric acid demonstrate that quantum chemistry is a powerful tool for investigating chemically complicated nucleation mechanisms. The calculations indicate that if the biogenic Criegee Intermediates have sufficiently long lifetimes in atmospheric conditions, the studied reaction may be an important source of nucleation precursors.

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According to Meno s paradox we cannot inquire into what we do not know because we do not know what we are inquiring into. There are many ways to interpret the paradox but the central issue about our ability to reach truth is a profound one. In the dialogue Meno, Plato presents the paradox and an outline of a solution which enables us to reach knowledge (epistēmē) through philosophical discussion. During the last century Meno has often been considered transitional between Socratic thinking and Plato s own philosophy, and thus the dialogue has not been adequately interpreted as an integrated whole. Therefore the distinctive epistemology of the dialogue has not gained due notice. In this thesis the dialogue is analysed as an integrated whole and the philosophical interpretation also takes into account its dramatic features. The thesis emphasises the role of language and definitions in acquiring knowledge. Among the results concerning these subjects is a new interpretation of Socrates s defintion of shape (schēma). The theory of anamnēsis all learning is recollection in the Meno is argued to answer the paradox philosophically although Plato s presentation also contains playful and ironic elements. The background of the way Plato presents his case is that he appreciated the fact that no argument can plausibly demonstrate that argumentation is able to reach truth. In the Meno, Plato makes the earliest explicit distinction between knowledge and true belief in the history of Western philosophy. He also gives a definition of knowledge which is the basis of the so called classical definition of knowledge as justified true belief. In the Meno, true beliefs become knowledge when someone ties them down by reasoning about the explanation. The analysis of the epistemology of the dialogue from this perspective gives an interpretation which integrates the central concepts of the epistemology in the dialogue elenchos, anamnēsis and hypothetical inquiry into a unified whole which contains a plausible argument according to which the ignorant can reach knowledge through discussion. The conception that emerges by such an analysis is interesting both from the point of view of current interests and that of the history of philosophy. The method of knowledge acquisition in the Meno can, for example, be seen as a predecessor of modern scientific methods. The Meno is the earliest Greek mathematical text that has survived in its original form. The analysis presented in the thesis of the geometric passages in the dialogue provides new results both concerning Socrates s geometry lesson with the slave and the example presenting the hypothetical method. Concerning the latter, a new interpretation is presented. Keywords: anamnēsis, epistēmē, knowledge, Meno s paradox, Plato

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Agriculture’s contribution to climate change is controversial as it is a significant source of greenhouse gases but also a sink of carbon. Hence its economic and technological potential to mitigate climate change have been argued to be noteworthy. However, social profitability of emission mitigation is a result from factors among emission reductions such as surface water quality impact or profit from production. Consequently, to value comprehensive results of agricultural climate emission mitigation practices, these co-effects to environment and economics should be taken into account. The objective of this thesis was to develop an integrated economic and ecological model to analyse the social welfare of crop cultivation in Finland on distinctive cultivation technologies, conventional tillage and conservation tillage (no-till). Further, we ask whether it would be privately or socially profitable to allocate some of barley cultivation for alternative land use, such as green set-aside or afforestation, when production costs, GHG’s and water quality impacts are taken into account. In the theoretical framework we depict the optimal input use and land allocation choices in terms of environmental impacts and profit from production and derive the optimal tax and payment policies for climate and water quality friendly land allocation. The empirical application of the model uses Finnish data about production cost and profit structure and environmental impacts. According to our results, given emission mitigation practices are not self-evidently beneficial for farmers or society. On the contrary, in some cases alternative land allocation could even reduce social welfare, profiting conventional crop cultivation. This is the case regarding mineral soils such as clay and silt soils. On organic agricultural soils, climate mitigation practices, in this case afforestation and green fallow give more promising results, decreasing climate emissions and nutrient runoff to water systems. No-till technology does not seem to profit climate mitigation although it does decrease other environmental impacts. Nevertheless, the data behind climate emission mitigation practices impact to production and climate is limited and partly contradictory. More specific experiment studies on interaction of emission mitigation practices and environment would be needed. Further study would be important. Particularly area specific production and environmental factors and also food security and safety and socio-economic impacts should be taken into account.

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Prolyl oligopeptidase (POP, prolyl endopeptidase, EC 3.4.21.26) is a serine-type peptidase (family S9 of clan SC) hydrolyzing peptides shorter than 30 amino acids. POP has been found in various mammalian and bacterial sources and it is widely distributed throughout different organisms. In human and rat, POP enzyme activity has been detected in most tissues, with the highest activity found mostly in the brain. POP has gained scientific interest as being involved in the hydrolyzis of many bioactive peptides connected with learning and memory functions, and also with neurodegenerative disorders. In drug or lesion induced amnesia models and in aged rodents, POP inhibitors have been able to revert memory loss. POP may have a fuction in IP3 signaling and it may be a possible target of mood stabilizing substances. POP may also have a role in protein trafficking, sorting and secretion. The role of POP during ontogeny has not yet been resolved. POP enzyme activity and expression have shown fluctuation during development. Specially high enzyme activities have been measured in the brain during early development. Reduced neuronal proliferation and differentation in presence of POP inhibitor have been reported. Nuclear POP has been observed in proliferating peripheral tissues and in cell cultures at the early stage of development. Also, POP coding mRNA is abundantly expressed during brain ontogeny and the highest levels of expression are associated with proliferative germinal matrices. This observation indicates a special role for POP in the regulation of neurogenesis during development. For the experimental part, the study was undertaken to investigate the expression and distribution of POP protein and enzymatic activity of POP in developing rat brain (from embryonic day 14 to post natal day 7) using immunohistochemistry, POP enzyme activity measurements and western blot-analysis. The aim was also to find in vivo confirmation of the nuclear colocalization of POP during early brain ontogeny. For immunohistochemistry, cryosections from the brains of the fetuses/rats were made and stained using specific antibody for POP and fluorescent markers for POP and nuclei. The enzyme activity assay was based on the fluorescence of 7- amino-4-methylcoumarin (AMC) generated from the fluorogenic substrate succinyl-glycyl-prolyl-7-amino-4-methylcoumarin (Suc-Gly-Pro-AMC) by POP. The amounts of POP protein and the specifity of POP antibody in rat embryos was confirmed by western blot analysis. We observed that enzymatic activity of POP is highest at embryonic day 18 while the protein amounts reach their peak at birth. POP was widely present throughout the developmental stages from embryonic day 14 to parturition day, although the POP-immunoreactivity varied abundantly. At embryonic days 14 and 18 notably amounts of POP was distributed at proliferative germinal zones. Furthermore, POP was located in the nucleus early in the development but is transferred to cytosol before birth. At P0 and P7 the POP-immunoreactivity was also widely observed, but the amount of POP was notably reduced at P7. POP was present in cytosol and in intercellular space, but no nuclear POP was observed. These findings support the idea of POP being involved in specific brain functions, such as neuronal proliferation and differentation. Our results in vivo confirm the previous cell culture results supporting the role of POP in neurogenesis. Moreover, an inconsistency of POP protein amounts and enzymatic activity late in the development suggests a strong regulation of POP activity and a possible non-hydrolytic role at that stage.

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Tutkimus on jatkoa Ruralia-instituutin syksyllä 2008 julkaisemalle metsäteollisuuden mahdollisen supistumisen aluetaloudellisia vaikutuksia selvittäneelle työlle. Päivitetty tutkimus on edellistä kattavampi, sillä selvitys ulottuu nyt kaikkiin Suomen massa- ja paperiteollisuuden yrityksiin. Massa- ja paperiteollisuuden vuoden 2007 alusta syksyyn 2009 ilmoittamat pysyvät kapasiteetin leikkaukset ovat yhteensä lähes 19,0 % vuoden 2007 tasoon verrattuna. Massan valmistuksessa menetykset ovat yli 20 % ja paperin/kartongin valmistuksessa noin 17 %. Supistamispäätökset merkitsevät kerroinvaikutuksineen yhteensä 1,4 miljardin euron ja 8 800 henkilötyövuoden menetystä. Kun vähennykset suhteutetaan menetyksiä kärsineiden maakuntien yhteenlaskettuun BKT:n ja työllisten määrään, toimenpiteet vastaavat 2,0 % laskua taloudellisessa kasvussa ja 0,8 % menetystä työllisyydessä. Vuoden 2008 lopulla vastaavat menetykset olivat 0,9 miljardia euroa ja 6 000 henkilötyövuotta. Vaikeudet keskittyvät itäiseen Suomeen. Kymenlaakso on kärsinyt suurimmat menetykset rahallisesti ja työllisten määrässä. Suhteellisesti eniten on menettänyt Kainuu. Pohjois-Savo nousee menettäjänä kolmen kärkeen, jos Stora Enson Varkauden tehtaiden sulkeminen toteutuu vuoden 2010 lopussa. Myös Keski-Suomessa, Lapissa ja Pohjanmaalla on suljettu kokonaisia tehtaita ja tästä on tullut selviä vaurioita. Pienemmillä tappioilla ovat selvinneet Etelä-Karjala, Pohjois-Karjala, Pohjois-Pohjanmaa ja Satakunta, joissa on ollut vain tuotannon seisokkeja ja/tai yksittäisiä tuotantolinjojen sulkemisia. Alueet, joiden elinkeinorakenne on monipuolinen, sopeutuvat nopeammin metsäteollisuuden supistumiseen. Tämä näkyy muun muassa pienempinä työllisyysmenetyksinä. Lisäksi aluetalouden koolla on merkitystä. Pienille aluetalouksille vaikutukset ovat voimakkaammat. Tutkimuksessa tarkasteltiin myös metsäteollisuuden rakennemuutoksen etenemisen vaikutuksia. Jos kehitys jatkuu negatiivisena, kuten Metla esitti keväällä 2009 tai pelätty kauhuskenaario alan tuotannon puoliintumisesta toteutuisi, kansantalouden menetykset olisivat merkittävät. Metlan skenaariossa BKT:n vähentyminen olisi kumulatiivisesti laskettuna suurimmillaan vuosien 2009 ja 2013 aikana, noin 450 miljoonaa euroa. Vastaavasti kauhuskenaariossa summa olisi lähes 700 miljoonaa euroa. Menetystä korostaa talouslama, minkä vuoksi muut alat eivät pysty täysin kompensoimaan massa- ja paperiteollisuuden vaikeuksia. Kokonaistuotanto näyttäisi kuitenkin toipuvan, mikäli nykyinen lama jäisi lyhyeksi. Työllisyys kärsisi huomattavasti kummassakin negatiivisessa skenaariossa. Vastapainoksi tutkittiin myös ns. sisäisen devalvaation sekä paperimarkkinoiden elpymisen vaikutusta. Sisäinen devalvaatio toteutuisi massa- ja paperiteollisuuden maltillisen palkkaratkaisun ja Ruotsin kruunun devalvoitumista vastaavan kustannusedun kautta. Kansainvälisten paperimarkkinoiden elpymisen vaikutusta tutkittiin vientihintoja ja -määriä nostamalla. Näistä tehokkaimmaksi osoittautui vientihintojen nousu. Myönteisten skenaarioiden vaikutusten ja nykyisten päätösten aiheuttamien aluetaloudellisten menetysten vertaaminen kuitenkin paljastaa, että vieläkin parempaa kehitystä vaaditaan. Kymenlaakso ja Pohjois-Savo jäisivät edelleen miinukselle.

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Listening to music involves a widely distributed bilateral network of brain regions that controls many auditory perceptual, cognitive, emotional, and motor functions. Exposure to music can also temporarily improve mood, reduce stress, and enhance cognitive performance as well as promote neural plasticity. However, very little is currently known about the relationship between music perception and auditory and cognitive processes or about the potential therapeutic effects of listening to music after neural damage. This thesis explores the interplay of auditory, cognitive, and emotional factors related to music processing after a middle cerebral artery (MCA) stroke. In the acute recovery phase, 60 MCA stroke patients were randomly assigned to a music listening group, an audio book listening group, or a control group. All patients underwent neuropsychological assessments, magnetoencephalography (MEG) measurements, and magnetic resonance imaging (MRI) scans repeatedly during a six-month post-stroke period. The results revealed that amusia, a deficit of music perception, is a common and persistent deficit after a stroke, especially if the stroke affects the frontal and temporal brain areas in the right hemisphere. Amusia is clearly associated with deficits in both auditory encoding, as indicated by the magnetic mismatch negativity (MMNm) response, and domain-general cognitive processes, such as attention, working memory, and executive functions. Furthermore, both music and audio book listening increased the MMNm, whereas only music listening improved the recovery of verbal memory and focused attention as well as prevented a depressed and confused mood during the first post-stroke months. These findings indicate a close link between musical, auditory, and cognitive processes in the brain. Importantly, they also encourage the use of listening to music as a rehabilitative leisure activity after a stroke and suggest that the auditory environment can induce long-term plastic changes in the recovering brain.

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Fish farming introduces nutrients, microbes and a wide variety of chemicals such as heavy metals, antifoulants and antibiotics to the surrounding environment. Introduction of antibiotics has been linked with the increased incidence of antibiotic resistant pathogenic bacteria in the farm vicinities. In this thesis molecular methods such as quantitative PCR and DNA sequencing were applied to analyze bacterial communities in sediments from fish farms and pristine locations. Altogether four farms and four pristine sites were sampled in the Baltic Sea. Two farm and two pristine locations were sampled over a surveillance period of four years. Furthermore, a new methodology was developed as a part of the study that permits amplifying single microbial genomes and capturing them according to any genetic traits, including antibiotic resistance genes. The study revealed that several resistance genes for tetracycline were found at the sediment underneath the aquaculture farms. The copy number of these genes remained elevated even at a farm that had not used any antibiotics since year 2000, six years before this study started. Similarly, an increase in the amount of mercury resistance gene merA was observed at the aquaculture sediment. The persistence of the resistance genes in absence of any selection pressure from antibiotics or heavy metals suggests that the genes may be introduced to the sediment by the farming process. This is also supported by the diversity pattern of the merA gene between farm and pristine sediments. The bacterial community-level changes in response to fish farming were very complex and no single phylogenetic groups were found that would be typical to fish farm sediments. However, the community structures had some correlation with the exposure to fish farming. Our studies suggest that the established approaches to deal with antibiotic resistance at the aquaculture, such as antibiotic cycling, are fundamentally flawed because they cannot prevent the introduction of the resistance genes and resistant bacteria to the farm area by the farming process. Further studies are required to study the entire fish farming process to identify the sources of the resistance genes and the resistant bacteria. The results also suggest that in order to prevent major microbiological changes in the surrounding aquatic environment, the farms should not be founded in shallow water where currents do not transport sedimenting matter from the farms. Finally, the technique to amplify and select microbial genomes will potentially have a considerable impact in microbial ecology and genomics.

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Bacteria growing in paper machines can cause several problems. Biofilms detaching from paper machine surfaces may lead to holes and spots in the end product or even break the paper web leading to expensive delays in production. Heat stable endospores will remain viable through the drying section of paper machine, increasing the microbial contamination of paper and board. Of the bacterial species regularly found in the end products, Bacillus cereus is the only one classified as a pathogen. Certain B. cereus strains produce cereulide, the toxin that causes vomiting disease in food poisonings connected to B. cereus. The first aim of this thesis was to identify harmful bacterial species colonizing paper machines and to assess the role of bacteria in the formation of end product defects. We developed quantitative PCR methods for detecting Meiothermus spp. and Pseudoxanthomonas taiwanensis. Using these methods I showed that Meiothermus spp. and Psx. taiwanensis are major biofoulers in paper machines. I was the first to be able to show the connection between end product defects and biofilms in the wet-end of paper machines. I isolated 48 strains of primary-biofilm forming bacteria from paper machines. Based on one of them, strain K4.1T, I described a novel bacterial genus Deinobacterium with Deinobacterium chartae as the type species. I measured the transfer of Bacillus cereus spores from packaging paper into food. To do this, we constructed a green fluorescent protein (GFP) labelled derivative of Bacillus thuringiensis and prepared paper containing spores of this strain. Chocolate and rice were the recipient foods when transfer of the labelled spores from the packaging paper to food was examined. I showed that only minority of the Bacillus cereus spores transferred into food from packaging paper and that this amount is very low compared to the amount of B. cereus naturally occurring in foods. Thus the microbiological risk caused by packaging papers is very low. Until now, the biological function of cereulide for the producer cell has remained unknown. I showed that B. cereus can use cereulide to take up K+ from environment where K+ is scarce: cereulide binds K+ ions outside the cell with high affinity and transports these ions across cell membrane into the cytoplasm. Externally added cereulide increased the growth rate of cereulide producing strains in medium where potassium was growth limiting. In addition, cereulide producing strains outcompeted cereulide non-producing B. cereus in potassium deficient environment, but not when the potassium concentration was high. I also showed that cereulide enhances biofilm formation of B. cereus.