102 resultados para arvot


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Diseases caused by the Lancefield group A streptococcus, Streptococcus pyogenes, are amongst the most challenging to clinicians and public health specialists alike. Although severe infections caused by S. pyogenes are relatively uncommon, affecting around 3 per 100,000 of the population per annum in developed countries, the case fatality is high relative to many other infections. Despite a long scientific tradition of studying their occurrence and characteristics, many aspects of their epidemiology remain poorly understood, and potential control measures undefined. Epidemiological studies can play an important role in identifying host, pathogen and environmental factors associated with risk of disease, manifestation of particular syndromes or poor survival. This can be of value in targeting prevention activities, as well directing further basic research, potentially paving the way for the identification of novel therapeutic targets. The formation of a European network, Strep-EURO, provided an opportunity to explore epidemiological patterns across Europe. Funded by the Fifth Framework Programme of the European Commission s Directorate-General for Research (QLK2.CT.2002.01398), the Strep-EURO network was launched in September 2002. Twelve participants across eleven countries took part, led by the University of Lund in Sweden. Cases were defined as patients with S. pyogenes isolated from a normally sterile site, or non-sterile site in combination with clinical signs of streptococcal toxic shock syndrome (STSS). All participating countries undertook prospective enhanced surveillance between 1st January 2003 and 31st December 2004 to identify cases diagnosed during this period. A standardised surveillance dataset was defined, comprising demographic, clinical and risk factor information collected through a questionnaire. Isolates were collected by the national reference laboratories and characterised according to their M protein using conventional serological and emm gene typing. Descriptive statistics and multivariable analyses were undertaken to compare characteristics of cases between countries and identify factors associated with increased risk of death or development of STSS. Crude and age-adjusted rates of infection were calculated for each country where a catchment population could be defined. The project succeeded in establishing the first European surveillance network for severe S. pyogenes infections, with 5522 cases identified over the two years. Analysis of data gathered in the eleven countries yielded important new information on the epidemiology of severe S. pyogenes infections in Europe during the 2000s. Comprehensive epidemiological data on these infections were obtained for the first time from France, Greece and Romania. Incidence estimates identified a general north-south gradient, from high to low. Remarkably similar age-standardised rates were observed among the three Nordic participants, between 2.2 and 2.3 per 100,000 population. Rates in the UK were higher still, 2.9/100,000, elevated by an upsurge in drug injectors. Rates from these northern countries were reasonably close to those observed in the USA and Australia during this period. In contrast, rates of reports in the more central and southern countries (Czech Republic, Romania, Cyprus and Italy) were substantially lower, 0.3 to 1.5 per 100,000 population, a likely reflection of poorer uptake of microbiological diagnostic methods within these countries. Analysis of project data brought some new insights into risk factors for severe S. pyogenes infection, especially the importance of injecting drug users in the UK, with infections in this group fundamentally reshaping the epidemiology of these infections during this period. Several novel findings arose through this work, including the high degree of congruence in seasonal patterns between countries and the seasonal changes in case fatality rates. Elderly patients, those with compromised immune systems, those who developed STSS and those infected with an emm/M78, emm/M5, emm/M3 or emm/M1 were found to be most likely to die as a result of their infection, whereas those diagnosed with cellulitis, septic arthritis, puerperal sepsis or with non-focal infection were associated with low risk of death, as were infections occurring during October. Analysis of augmented data from the UK found use of NSAIDs to be significantly associated with development of STSS, adding further fuel to the debate surrounding the role of NSAIDs in the development of severe disease. As a largely community-acquired infection, occurring sporadically and diffusely throughout the population, opportunities for control of severe infections caused by S. pyogenes remain limited, primarily involving contact chemoprophylaxis where clusters arise. Analysis of UK Strep-EURO data were used to quantify the risk to household contacts of cases, forming the basis of national guidance on the management of infection. Vaccines currently under development could offer a more effective control programme in future. Surveillance of invasive infections caused by S. pyogenes is of considerable public health importance as a means of identifying long and short-term trends in incidence, allowing the need for, or impact of, public health measures to be evaluated. As a dynamic pathogen co-existing among a dynamic population, new opportunities for exploitation of its human host are likely to arise periodically, and as such continued monitoring remains essential.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Populations in developed countries are ageing fast. The elderly have the greatest incidence of de-mentia, and thus the increase in the number of demented individuals, increases the immediate costs for the governments concerning healthcare and hospital treatment. Attention is being paid to disorders behind cognitive impairment with behavioural and psychological symptoms, which are enormous contributors to the hospital care required for the elderly. The highest dreams are in prevention; however, before discovering the tools for preventing dementia, the pathogenesis behind dementia disorders needs to be understood. Dementia with Lewy bodies (DLB), a relatively recently discovered dementia disorder compared to Alzheimer’s disease (AD), is estimated to account for up to one third of primary degenerative dementia, thus being the second most common cause of dementia in the elderly. Nevertheless, the impact of neuropathological and genetic findings on the clinical syndrome of DLB is not fully established. In this present series of studies, the frequency of neuropathological findings of DLB and its relation to the clinical findings was evaluated in a cohort of subjects with primary degenerative dementia and in a population-based prospective cohort study of individuals aged 85 years or older. α-synuclein (αS) immunoreactive pathology classifiable according to the DLB consensus criteria was found in one fourth of the primary degenerative dementia subjects. In the population-based study, the corresponding figure was one third of the population, 38% of the demented and one fifth of the non-demented very elderly Finns. However, in spite of the frequent discovery of αS pathology, its association with the clinical symptoms was quite poor. Indeed, the common clinical features of DLB, hypokinesia and visual hallucinations, associated better with the severe neurofibrillary AD-type pathology than with the extensive (diffuse neocortical) αS pathology when both types of pathology were taken into account. The severity of the neurofibrillary AD-type pathology (Braak stage) associated with the extent of αS pathology in the brain. In addition, the genetic study showed an interaction between tau and αS; common variation in the αS gene (SNCA) associated significantly with the severity of the neurofibrillary AD-type pathology and nominally significantly with the extensive αS pathology. Further, the relevance and temporal course of the substantia nigra (SN) degeneration and of the spinal cord αS pathology were studied in relation to αS pathology in the brain. The linear association between the extent of αS pathology in the brain and the neuron loss in SN suggests that in DLB the degeneration of SN proceeds as the αS pathology extends from SN to the neocortex instead of early destruction of SN seen in Parkinson’s disease (PD). Furthermore, the extent of αS pathology in the brain associated with the severity of αS pathology in the thoracic and sacral autonomic nuclei of the spinal cord. The thoracic αS pathology was more common and more severe compared to sacral cord, suggesting that the progress of αS pathology proceeds downwards from the brainstem towards the sacral spinal cord.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The issue of the usefulness of different prosopis species versus their status as weeds is a matter of hot debate around the world. The tree Prosopis juliflora had until 2000 been proclaimed weedy in its native range in South America and elsewhere in the dry tropics. P. juliflora or mesquite has a 90-year history in Sudan. During the early 1990s a popular opinion in central Sudan and the Sudanese Government had begun to consider prosopis a noxious weed and a problematic tree species due to its aggressive ability to invade farmlands and pastures, especially in and around irrigated agricultural lands. As a consequence prosopis was officially declared an invasive alien species also in Sudan, and in 1995 a presidential decree for its eradication was issued. Using a total economic valuation (TEV) approach, this study analysed the impacts of prosopis on the local livelihoods in two contrasting irrigated agricultural schemes. Primarily a problem-based approach was used in which the derivation of non-market values was captured using ecological economic tools. In the New Halfa Irrigation Scheme in Kassala State, four separate household surveys were conducted due to diversity between the respective population groups. The main aim was here to study the magnitude of environmental economic benefits and costs derived from the invasion of prosopis in a large agricultural irrigation scheme on clay soil. Another study site, the Gandato Irrigation Scheme in River Nile State represented impacts from prosopis that an irrigation scheme was confronted with on sandy soil in the arid and semi-arid ecozones along the main River Nile. The two cases showed distinctly different effects of prosopis but both indicated the benefits to exceed the costs. The valuation on clay soil in New Halfa identified a benefit/cost ratio of 2.1, while this indicator equalled 46 on the sandy soils of Gandato. The valuation results were site-specific and based on local market prices. The most important beneficial impacts of prosopis on local livelihoods were derived from free-grazing forage for livestock, environmental conservation of the native vegetation, wood and non-wood forest products, as well as shelterbelt effects. The main social costs from prosopis were derived from weeding and clearing it from farm lands and from canalsides, from thorn injuries to humans and livestock, as well as from repair expenses vehicle tyre punctures. Of the population groups, the tenants faced most of the detrimental impacts, while the landless population groups (originating from western and eastern Sudan) as well as the nomads were highly dependent on this tree resource. For the Gandato site the monetized benefit-cost ratio of 46 still excluded several additional beneficial impacts of prosopis in the area that were difficult to quantify and monetize credibly. In River Nile State the beneficial impact could thus be seen as completely outweighing the costs of prosopis. The results can contributed to the formulation of national and local forest and agricultural policies related to prosopis in Sudan and also be used in other countries faced with similar impacts caused by this tree.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Tutkimuksen tavoitteet Tutkimuksen teoreettinen osa esittelee yhteiskunnallisten hankkeiden arvottamiseen liittyvää koti- ja ulkomaista kirjallisuutta. Empiirinen osa tutkii Savonlinnasta poimitun metsätilaotoksen avulla maiseman- ja luonnonhoidon aiheuttamia taloudellisia vaikutuksia tilojen metsänomistajille sekä vertaa näitä tuloksia haastattelututkimuksesta saatuihin vastauksiin maksuhalukkuudesta monimuotoisuuden hyväksi. Lähdeaineisto Metsämaiseman- ja luonnonhoidon aiheuttamia taloudellisia vaikutuksia tutkittaessa case-aineistona käytettiin keskeisen Saimaan Pihlajaveden saaristoalueen 24 tilaa, joiden omistajat olivat tilanneet Etelä-Savon metsäkeskukselta uudentyyppisen maiseman- ja luonnonhoidon arvot huomioivan metsäsuunnitelman. Samalla aineistolla suoritettiin myös metsänomistajien haastattelu, jonka avulla selvitettiin metsänomistajien maksuhalukkuutta monimuotoisuudesta ja maisemamansuojelusta. Lisäksi kysyttiin mielipiteitä nykyisistä metsänhoitosuosituksista ja alueelle kaavailluista luonnonsuojeluhankkeista. Aineiston käsittely Taloudellisia vaikutuksia tutkittaessa maisema- ja luontoarvoja korostavaa metsäsuunnitelmalaskelmaa verrattiin maksimaaliseen puuntuotantoon tähtäävään metsäsuunnitelmaan. Näiden kahden vaihtoehtoisten laskelman välinen erotus tulkittiin monimuotoisuuden turvaamisen metsälötason puuntuotannolliseksi vaikutukseksi. Vastaavasti haastatteluosuudessa metsänomistajilta kysyttiin, kuinka paljon he olisivat valmiita luopumaan metsätuloistaan monimuotoisuuden edistämiseksi. Maksuhalukkuutta tutkittaessa käytettiin contingent valuation -menetelmää. Tulokset Siirtyminen ns. perinteisestä metsänkäsittelystä maiseman- ja luonnonhoidon huomioivaan metsänkäsittelyyn pienentää metsästä saatavia nettotuloja ensimmäisen kymmenvuotiskauden aikana 36 % eli 289 mk/ha vuosittain. Vastaavasti metsänomistajien maksuhalukkuus monimutoisuuden edistämisestä oli 5,3 % metsätuloista, joka on rahassa 18 mk/ha vuosittain. Nettotulojen merkittävä pieneneminen selittyy kohteen arvokkailla maisema-arvoilla ja ekologisten elinympäristöjen runsaalla lukumäärällä. Tulosten tilastollista luotettavuutta ei otoksen pienuuden vuoksi voitu tarkastella. Avainsanat: metsämaiseman- ja luonnonhoito, metsätulot, maksuhalukkuus, monimuotoisuus, Pihlajaveden saaristo

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Fatty acids, fibre, carotenoids and tocopherols in relation to glucose metabolism in subjects at high risk for type 2 diabetes a cross-sectional analysis Type 2 diabetes (T2D) is a heterogeneous disorder of carbohydrate, lipid and protein metabolism, resulting from genetics, environmental influences and interactions between these. The disease is characterized by insulin resistance, β-cell dysfunction, hepatic glucose overproduction and disordered fat mobilization and storage. The literature on associations between dietary factors and glucose metabolism is inconsistent. One factor behind the discrepant results may be genetic heterogeneity of study populations. Data on nutrient-gene interactions in relation to glucose metabolism are scarce. Thus, investigating high-risk populations and exploring nutrient-gene interactions are essential for improving the understanding of T2D aetiology. Ideally, this information could help to develop prevention programmes that take into account the genetic predisposition to the disease. In this study, associations between measures of glucose metabolism predicting T2D and fatty acids, antioxidative nutrients and fibre were examined in a high-risk population, i.e., in non-diabetic relatives of affected patients. Interactions between the PPARG Pro12Ala polymorphism and fatty acids on glucose metabolism were taken into consideration. This common polymorphism plays an important role in the regulation of glucose metabolism. The inverse associations observed between dietary fibre and insulin resistance are consistent with the prevailing recommendations urging increased intake of fibre to prevent T2D. Beneficial associations observed between the intake of carotenoids and glucose levels stress that a high consumption of vegetables, fruits and berries rich in carotenoids might also play a role in the prevention of T2D. Whether tocopherols have an independent association with glucose metabolism remains questionable. Observed interactions between fatty acids and glucose metabolism suggest that a high intake of palmitic acid is associated with high fasting glucose levels mainly in female Ala allele carriers. Furthermore, the PPARG Pro12Ala polymorphism may modify the metabolic response to dietary marine fat. The beneficial associations of high intake of marine n 3 fatty acids with insulin resistance and glucose levels may be restricted to carriers of the Ala allele. The findings pertain to subjects with a family history of T2D, and the cross-sectional nature of the study precludes inferences about causality. Results nevertheless show that associations of dietary factors with glucose metabolism may be modulated by the genetic makeup of an individual. Additional research is warranted to elucidate the role of probably numerous nutrient-gene interactions, some of which may be sex-specific, in the aetiology of T2D.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The purpose of this work was to identify some of the genes of the catabolic route of L-rhamnose in the yeast Pichia stipitis. There are at least two distinctly different pathways for L-rhamnose catabolism. The one described in bacteria has phosphorylated intermediates and the enzymes and the genes of this route have been described. The pathway described in yeast does not have phosphorylated intermediates. The intermediates and the enzymes of this pathway are known but none of the genes have been identified. The work was started by purifying the L-rhamnose dehydrogenase, which oxidates L-rhamnose to rhamnonic acid-gamma-lactone. NAD is used as a cofactor in this reaction. A DEAE ion exchange column was used for purification. The active fraction was further purified using a non-denaturing PAGE and the active protein identified by zymogram staining. In the last step the protein was separated in a SDS-PAGE, the protein band trypsinated and analysed by MALDI-TOF MS. This resulted in the identification of the corresponding gene, RHA1, which was then, after a codon change, expressed in Saccharomyces cerevisiae. Also C- or N-terminal histidine tags were added but as the activity of the enzyme was lost or strongly reduced these were not used. The kinetic properties of the protein were analysed in the cell extract. Substrate specifity was tested with different sugars; L-rhamnose, L-lyxose and L-mannose were oxidated by the enzyme. Vmax values were 180 nkat/mg, 160 nkat/mg and 72 nkat/mg, respectively. The highest affinity was towards L-rhamnose, the Km value being 0.9 mM. Lower affinities were obtained with L-lyxose, Km 4.3 mM, and L-mannose Km 25 mM. Northern analysis was done to study the transcription of RHA1 with different carbon sources. Transcription was observed only on L-rhamnose suggesting that RHA1 expression is L-rhamnose induced. A RHA1 deletion cassette for P. stipitis was constructed but the cassette had integrated randomly and not targeted to delete the RHA1 gene. Enzyme assays for L-lactaldehyde dehydrogenase were done similarly to L-rhamnose dehydrogenase assays. NAD is used as a cofactor also in this reaction where L-lactaldehyde is oxidised to L-lactate. The observed enzyme activities were very low and the activity was lost during the purification procedures.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Tutkimuksen tarkoitus on kartoittaa Suomen talviukkosten ominaisuuksia ja klimatologiaa. Tiedot Suomen talviukkosten klimatologista tutkimusta varten kerättiin mm. salamanpaikantimilta ja ihmisten IL:lle tiedottamista havainnoista, SYNOP-kartoilta, rintama-analyyseistä, luotauksista ja luotaustietojen pohjalta piirretyistä salamakartoista sekä sadetutkan kuvista. Tutkimuksessa määriteltiin talviukkoseksi yksi tai useampi salamahavainto säätilanteessa, jossa salamahavaintopaikkaan ja -aikaan nähden lähimmistä synop-havainnoista ainakin yhdessä on havaittu joko ≤ 0 °C lämpötila tai lumi- tai räntäsadetta. Näin rajattuna vuosina 2003-2007 talviukkostapauksia oli 19 kpl. Tapaukset jakaantuivat melko tasaisesti loka-marraskuun vaihteen ja huhtikuun välille, pienet maksimit olivat marras- ja helmikuussa. Tapausten esiintymisajankohtia rajoitti siis vain talviukkosten määritelmän mukaisten sääolosuhteiden esiintyminen. Vuorokaudenajalla ei ollut merkittävää vaikutusta talvisalamoiden esiintymiselle. Alueellisesti talviukkoset painottuivat maan lounaisosaan mutta niitä havaittiin koko maassa Käsivarren Lappia myöten. 16 tapauksessa 19:sta talviukkoset havaittiin okluusiorintamaksi analysoidun rintaman yhteydessä. Yhdessä tapauksessa rintama oli analysoitu kylmäksi ja kahdessa rintama-analyysi oli epäselvä. Matalapaineen keskus sijaitsi iskuhavaintopaikkoihin nähden yleensä lännen puolella. Lännen puolen yleisyyden aiheutti okluusiorintamien kiertosuunta myötäpäivään matalapaineen keskukseen nähden. Pintalämpötila oli lähes kaikissa talviukkostapauksissa lähellä nollaa ja havaintopaikan lähellä olevissa SYNOP-havainnoissa havaittiin useissa tapauksissa sadetta sekä vetenä että kiinteässä olomuodossa. CAPE:n arvot olivat joko nollassa tai hyvin lähellä sitä iskuhavaintoihin nähden lähimmissä luotauksissa. Lämmintä advektiota havaittiin lähes kaikissa tutkituissa luotauksissa, myös sulan meren vaikutus näkyi tuloksissa talviukkosia edistävänä tekijänä. Maasalamoita havaittiin talviukkosten yhteydessä useimmin 1 tai 2 ja iskuja salamaa kohden 1 tai 2. Havaituista maasalamoista positiivisia oli 46 % ja negatiivisia 54 %. Tapaustutkimukset tehtiin kahdesta vuosien 2003-2007 talviukkosia hyvin edustavasta tapauksesta sekä yhdestä salamamäärältään poikkeuksellisen runsaasta tapauksesta.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Tässä Pro Gradu -tutkielmassa oli tarkoitus määrittää ne lämpötilan ääriarvojen maksimi ja minimi arvot, jotka ovat vielä fysikaalisesti mahdollisia Suomen ilmastossa. Työssä käytettiin hyväksi kahta eri yksidimensioista ilmakehämallia, 1D-H634 sekä 1D-RCA3. Ensiksi mainittu pohjaa HIRLAM 6.3.4- malliin. Jälkimmäisessä mallissa HIRLAMin pintaprosessit on korvattu ruotsalaisen Rossby-keskuksen RCA3 -mallin fysiikalla. Tutkimukseen otettiin mukaan kaikki kolme luotausasemaa Suomesta (Jokioinen, Jyväskylä ja Sodankylä). Työ aloitettiin poimimalla Ilmatieteen laitoksen ilmastotietokannasta ne ajankohdat, joina kahden metrin lämpötila on ylittänyt kesällä +30°C ja alittanut talvella -35°C. Seuraavaksi etsittiin näitä ajanjaksoja vastaavat luotaustiedot. Luotauksia tutkimalla pyrittiin selvittämään mitkä tekijät vaikuttivat äärilämpötilojen esiintymiseen. Tämän jälkeen nämä luotaustiedot interpoloitiin vastaamaan mallin 40 vertikaalitasoa. Nämä tiedot syötettiin malleille yhdessä päivämäärän, kellonajan sekä koordinaattien kanssa ja tulokseksi saatiin vuorokauden kahden metrin lämpötilakäyrät. Koska yksidimensioiset mallit eivät ota huomioon lämmön advektiota, laskettiin Euroopan keskipitkien sääennusteiden keskuksen (ECMWF) ERA40-uusanalyysien pohjalta kyseisiä ajanhetkiä vastaavat lämmön advektiot. Lisäksi laskettiin keskimääräiset advektion vuorokausirytmit kesällä (kesä-heinä-elo) ja talvella (tammi-helmi). Suomesta saatujen luotaustietojen pohjalta tehtyjen ajojen kahden metrin lämpötilat eivät kesätilanteessa kyenneet ylittämään Turussa vuonna 1914 mitattua lämpötilaennätystä +35,9°C. Verrattaessa kuitenkin malliajojen tuloksia tehtyihin havaintoihin, voitiin kesätilanteissa todeta mallin antavan jopa 5°C lämpimämpiä arvoja kuin kyseisissä tilanteissa on mitattu. Lopuksi päätettiin tehdä malliajo, jossa luotaus otettiin Tallinnan lentoasemalta elokuulta 1992. Tämän luotaustiedon pohjalta tehdyn ajon tulos (+36,4°C) ylitti Suomessa havaitun lämpötilaennätyksen. Talvitilanteissa 1D-H634-malli ei puolestaan kyennyt saavuttamaan Suomen pakkasennätystä (-51,5°C), joka mitattiin Kittilässä vuonna 1999. Mallitetut pakkaslukemat olivat kuitenkin suurimmassa osassa ajoja kireämpiä kuin mitä kyseisten tilanteiden havainnot kertovat. Käytettäessä 1D-RCA3-mallia päästiin pakkasissa -53,8°C:seen ja pakkaslukemat olivat muutenkin paljon alhaisempia verrattuna 1D-H634- mallin tuloksiin.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Työssä tarkasteltiin ilmakehän yleisen kiertoliikkeen mallin, ECHAM5:n, ja Euroopan keskipitkien sääennusteiden keskuksen uudelleenanalyysijärjestelmän, ERA-40:n, lumen vesiarvon ja lumisten alueiden pinnan albedon mallintamista. Tarkoituksena oli selvittää näiden välisiä eroja sekä sitä, kuinka hyvin ECHAM5 kuvaa nykyilmaston lumioloja. Esimerkinomaisesti tarkasteltiin myös Rossby-keskuksen alueellisen ilmastomallin, RCA3:n, lumen mallintamistapaa. ECHAM5-simulaatioissa käytetty pakote oli havaintojen mukainen meriveden pintalämpötilan ja merijään jakauma. ECHAM5:n ja ERA-40:n aineistoja vertailtiin jaksolla 1986-1990 Pohjois-Euraasian alueella. ERA-40:n lumen vesiarvoja verrattiin lisäksi INTAS-SCCONE-hankkeen havaintoaineistoon. Saatujen tulosten mukaan ECHAM5:n lumen vesiarvo oli monilla alueilla ERA-40:n lumen vesiarvoa pienempi. Suurimmillaan erot olivat vesiarvon maksimialueilla Euraasian keskiosissa. ECHAM5:ssä myös eri vuosien välinen vaihtelu oli pienempää kuin ERA-40:ssä. Varsinkin tarkastelujakson viimeisinä vuosina, 1989 ja 1990, lumen vesiarvo sai Pohjois-Euroopan alueella ERA-40:n mukaan hyvin matalia arvoja, jotka selittyvät NAO-indeksin korkeilla arvoilla. NAO-ilmiön voimakkuus 1980-luvun lopulla ei kuitenkaan erotu ECHAM5:n lumen vesiarvossa. ERA-40:n lumianalyysissä on mukana lumensyvyyshavaintoja, mikä on suurin tuloksiin eroa aiheuttava tekijä. Lienee myös mahdollista, että ECHAM5-simulaatioissa käytetty pakote ei ole riittävän voimakas tuottamaan kaikilta osin realistista lumen vesiarvon jakaumaa. ERA-40:n ja INTAS-SCCONE-aineiston välillä ei ollut kovin suuria eroja. Lumisten alueiden pinnan albedon osana käytetty lumialbedo on ERA-40:ssä ennustettava muuttuja, ECHAM5:ssä se parametrisoidaan. Saatujen tulosten mukaan pinnan albedon arvot ovat ECHAM5:ssä laajalti suurempia kuin ERA-40:ssä. Erot aiheutuvat albedojen erilaisesta laskentatavasta sekä mallien erilaisista kasvillisuusjakaumista. ECHAM5 aliarvioi kasvillisuuden albedoa pienentävän vaikutuksen varsinkin pohjoisen havumetsävyöhykkeen alueella. ERA-40:n pinnan albedo lieneekin realistisempi kuin ECHAM5:n.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The driving force behind this study has been the need to develop and apply methods for investigating the hydrogeochemical processes of significance to water management and artificial groundwater recharge. Isotope partitioning of elements in the course of physicochemical processes produces isotopic variations to their natural reservoirs. Tracer property of the stable isotope abundances of oxygen, hydrogen and carbon has been applied to investigate hydrogeological processes in Finland. The work described here has initiated the use of stable isotope methods to achieve a better understanding of these processes in the shallow glacigenic formations of Finland. In addition, the regional precipitation and groundwater records will supplement the data of global precipitation, but as importantly, provide primary background data for hydrological studies. The isotopic composition of oxygen and hydrogen in Finnish groundwaters and atmospheric precipitation was determined in water samples collected during 1995 2005. Prior to this study, no detailed records existed on the spatial or annual variability of the isotopic composition of precipitation or groundwaters in Finland. Groundwaters and precipitation in Finland display a distinct spatial distribution of the isotopic ratios of oxygen and hydrogen. The depletion of the heavier isotopes as a function of increasing latitude is closely related to the local mean surface temperature. No significant differences were observed between the mean annual isotope ratios of oxygen and hydrogen in precipitation and those in local groundwaters. These results suggest that the link between the spatial variability in the isotopic composition of precipitation and local temperature is preserved in groundwaters. Artificial groundwater recharge to glaciogenic sedimentary formations offers many possibilities to apply the isotopic ratios of oxygen, hydrogen and carbon as natural isotopic tracers. In this study the systematics of dissolved carbon have been investigated in two geochemically different glacigenic groundwater formations: a typical esker aquifer at Tuusula, in southern Finland and a carbonate-bearing aquifer with a complex internal structure at Virttaankangas, in southwest Finland. Reducing the concentration of dissolved organic carbon (DOC) in water is a primary challenge in the process of artificial groundwater recharge. The carbon isotope method was used to as a tool to trace the role of redox processes in the decomposition of DOC. At the Tuusula site, artificial recharge leads to a significant decrease in the organic matter content of the infiltrated water. In total, 81% of the initial DOC present in the infiltrated water was removed in three successive stages of subsurface processes. Three distinct processes in the reduction of the DOC content were traced: The decomposition of dissolved organic carbon in the first stage of subsurface flow appeared to be the most significant part in DOC removal, whereas further decrease in DOC has been attributed to adsorption and finally to dilution with local groundwater. Here, isotope methods were used for the first time to quantify the processes of DOC removal in an artificial groundwater recharge. Groundwaters in the Virttaankangas aquifer are characterized by high pH values exceeding 9, which are exceptional for shallow aquifers on glaciated crystalline bedrock. The Virttaankangas sediments were discovered to contain trace amounts of fine grained, dispersed calcite, which has a high tendency to increase the pH of local groundwaters. Understanding the origin of the unusual geochemistry of the Virttaankangas groundwaters is an important issue for constraining the operation of the future artificial groundwater plant. The isotope ratios of oxygen and carbon in sedimentary carbonate minerals have been successfully applied to constrain the origin of the dispersed calcite in the Virttaankangas sediments. The isotopic and chemical characteristics of the groundwater in the distinct units of aquifer were observed to vary depending on the aquifer mineralogy, groundwater residence time and the openness of the system to soil CO2. The high pH values of > 9 have been related to dissolution of calcite into groundwater under closed or nearly closed system conditions relative to soil CO2, at a low partial pressure of CO2.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The importance of supercontinents in our understanding of the geological evolution of the planet Earth has been recently emphasized. The role of paleomagnetism in reconstructing lithospheric blocks in their ancient paleopositions is vital. Paleomagnetism is the only quantitative tool for providing ancient latitudes and azimuthal orientations of continents. It also yields information of content of the geomagnetic field in the past. In order to obtain a continuous record on the positions of continents, dated intrusive rocks are required in temporal progression. This is not always possible due to pulse-like occurrences of dykes. In this work we demonstrate that studies of meteorite impact-related rocks may fill some gaps in the paleomagnetic record. This dissertation is based on paleomagnetic and rock magnetic data obtained from samples of the Jänisjärvi impact structure (Russian Karelia, most recent 40Ar-39Ar age of 682 Ma), the Salla diabase dyke (North Finland, U-Pb 1122 Ma), the Valaam monzodioritic sill (Russian Karelia, U-Pb 1458 Ma), and the Vredefort impact structure (South Africa, 2023 Ma). The paleomagnetic study of Jänisjärvi samples was made in order to obtain a pole for Baltica, which lacks paleomagnetic data from 750 to ca. 600 Ma. The position of Baltica at ca. 700 Ma is relevant in order to verify whether the supercontinent Rodinia was already fragmented. The paleomagnetic study of the Salla dyke was conducted to examine the position of Baltica at the onset of supercontinent Rodinia's formation. The virtual geomagnetic pole (VGP) from Salla dyke provides hints that the Mesoproterozoic Baltica - Laurentia unity in the Hudsonland (Columbia, Nuna) supercontinent assembly may have lasted until 1.12 Ga. Moreover, the new VGP of Salla dyke provides new constraint on the timing of the rotation of Baltica relative to Laurentia (e.g. Gower et al., 1990). A paleomagnetic study of the Valaam sill was carried out in order to shed light into the question of existence of Baltica-Laurentia unity in the supercontinent Hudsonland. Combined with results from dyke complex of the Lake Ladoga region (Schehrbakova et al., 2008) a new robust paleomagnetic pole for Baltica is obtained. This pole places Baltica on a latitude of 10°. This low latitude location is supported also by Mesoproterozoic 1.5 1.3 Ga red-bed sedimentation (for example the Satakunta sandstone). The Vredefort impactite samples provide a well dated (2.02 Ga) pole for the Kaapvaal Craton. Rock magnetic data reveal unusually high Koenigsberger ratios (Q values) in all studied lithologies of the Vredefort dome. The high Q values are now first time also seen in samples from the Johannesburg Dome (ca. 120 km away) where there is no impact evidence. Thus, a direct causative link of high Q values to the Vredefort impact event can be ruled out.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The object of this dissertation is to study globally defined bounded p-harmonic functions on Cartan-Hadamard manifolds and Gromov hyperbolic metric measure spaces. Such functions are constructed by solving the so called Dirichlet problem at infinity. This problem is to find a p-harmonic function on the space that extends continuously to the boundary at inifinity and obtains given boundary values there. The dissertation consists of an overview and three published research articles. In the first article the Dirichlet problem at infinity is considered for more general A-harmonic functions on Cartan-Hadamard manifolds. In the special case of two dimensions the Dirichlet problem at infinity is solved by only assuming that the sectional curvature has a certain upper bound. A sharpness result is proved for this upper bound. In the second article the Dirichlet problem at infinity is solved for p-harmonic functions on Cartan-Hadamard manifolds under the assumption that the sectional curvature is bounded outside a compact set from above and from below by functions that depend on the distance to a fixed point. The curvature bounds allow examples of quadratic decay and examples of exponential growth. In the final article a generalization of the Dirichlet problem at infinity for p-harmonic functions is considered on Gromov hyperbolic metric measure spaces. Existence and uniqueness results are proved and Cartan-Hadamard manifolds are considered as an application.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Tutkielmassa on vertailtu tuomarin roolia siviiliprosessin dispositiivisissa asioissa ja hallintoprosessissa. Vertailussa käytetään apuna kahta ratkaisumallia, jotka ovat peräisin Carol Gilliganin kehittelemästä sukupuolten moraalikehityspsykologiasta. Siten naisen moraalisissa ratkaisuissa käytetään arvoja, jotka ovat muotoutuneet samaistumisen kokemuksena hoivaajaan ja joissa ihmissuhteiden ja vastuun merkitys on korostunut. Naisen eettisenä ratkaisumallina on vastuun etiikka, jossa painottuvat tilannekohtaisen oikeudenmukaisuuden arvot, vastuu, kohtuus ja joustavuus. Vastuun oikeuden heikko kohta on se, että heikompi ei vaadi oikeuksiaan ja hänen asemansa voi heikentyä edelleen. Vastuun etiikka liitetään tutkielmassa hallintoprosessin tuomarin rooliin, koska hallintoprosessin tuomari toimii virallisperiaatteen alaisena ja on selvitysvastuussa joustavassa prosessissa. Miehen moraalikehitys kumpuaa erillisyyden tunteesta hoivaajaansa ja siinä korostuu yksilöllisyys ja oikeuksien painottuminen. Eettinen ratkaisumalli on oikeuden etiikka, jolle on tyypillistä reilun pelin säännöt, tasapuolisuus, ongelmien abstrahoituminen ja muodollisuus. Oikeuden etiikan heikko kohta on tilannekohtainen kohtuuttomuus oikeuksien korostamisen vuoksi. Tämä ratkaisumalli liitetään siviiliprosessin dispositiiviseen menettelyyn. Tutkielman näkökulmana on yksityisen asianosaisen asema ja kokemus prosessissa. Asianosainen on eri asemassa prosesseissa siinä suhteessa, että siviiliprosessiin osallistuminen edellyttää käytännössä asianajajan apuun turvautumista. Hallintoprosessissa on pyrkimys siihen, että yksityinen pärjää ilman avustajaa. Syynä on pidetty heikkoa kaksiasianosaissuhdetta ja sitä, että yksityisen asemaa on tasapainotettava suhteessa viranomaistahoon. Silti siviiliprosessissa asetelma saattaa yhtä hyvin olla epätasapainossa siten, että yksityinen on tiedollisesti ja taidollisesti heikommassa asemassa kuin vastapuolensa. Tuomarin roolia vertaillaan prosesseissa menettelyperiaatteiden ja vastuun jakautumisen sääntöjen avulla. Asianosaiset ovat siviiliprosessissa vastuussa asian oikeudellistamisesta. Myös totuuden käsite muodostuu erilaiseksi, koska selvitysvastuullinen hallintotuomari on lopulta vastuussa selvityksen riittävyydestä, kun taas siviiliprosessissa asianosaisen oikeussuojapyyntö rajaa totuuden. Siviiliprosessia on moitittu liiasta muodollisuudesta varsinkin sovittelukeskustelussa. Muodollisuus vaikeuttaa asianosaisen osallistumismahdollisuuksia ja etäännyttää häntä oikeusjutun käsittelystä. Muodollisuus edistää kuitenkin oikeusvarmuutta. Tuomioistuinsovittelussa on sanouduttu irti muodollisuudesta ja siinä sivussa myös aineellisesta oikeudesta. Sovittelussa on olemassa vaara siitä, että heikomman asema heikkenee entisestään. Joustava prosessi nähdään asianosaisen osallistumisen kannalta suotavampana menettelynä. Joustavuuden syynä on hallintoprosessissa käsiteltävien asioiden monimuotoisuus. Joustavuus ilmenee käytännössä virallisperiaatteen noudattamisena. Tuomarin toiminnan on oltava puolueetonta, mutta heikko asianosaissuhde ja yksityisen heikompi asema vaikuttavat siten, että tuomarin toiminta on tasapainottavaa paitsi yksityisen suuntaan, mutta myös yleisen edun suuntaan. Joustavuuden vuoksi asianosaisen luottamus saattaa vaarantua sen vuoksi, että prosessi ei ole ennakoitavaa ja prosessiasetelmaa on vaikea hahmottaa. Siten hallintoprosessissa onkin paineita oikeudellistamisen suuntaa. Joustavuuden rajana on puolueettomuuden vaatimus. Siviiliprosessissa puolueettomuus on kaksiasianosaissuhteen vuoksi korostuneempi kuin hallintoprosessissa. Puolueettomuuden vaatimus saattaa kuitenkin vaikuttaa siten, että tuomari ei voi auttaa heikompaa osapuolta riidan oikeudellistamisessa. Siten puolueettomuudella legitimoidaan vahvemman prosessiosapuolen asemaa. Olisiko virallisperiaatteesta apua siviiliprosessin muodollisuuden ongelmaan ja tasapainottamaan epätasapainoista suhdetta prosessiosapuolten välillä? Siviiliprosessi ja hallintoprosessi ovat lähentyneet toisiaan ja oikeuskirjallisuudessa on ennustettu tämän kehityksen jatkuvan. Myös oikeuden ja vastuun etiikka lähentyvät aikuisiässä toisiaan siten, että vastuun etiikka vahvistuu oikeuksien tärkeyden hahmottamisella ja oikeuden etiikassa kehittyy käsitys kohtuudesta. Prosessien kehityksessä olisi toivottavaa, että otettaisiin oppia toisen prosessilajin kehityksestä ja kokemuksista.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This study addresses the following question: How to think about ethics in a technological world? The question is treated first thematically by framing central issues in the relationship between ethics and technology. This relationship has three distinct facets: i) technological advance poses new challenges for ethics, ii) traditional ethics may become poorly applicable in a technologically transformed world, and iii) the progress in science and technology has altered the concept of rationality in ways that undermine ethical thinking itself. The thematic treatment is followed by the description and analysis of three approaches to the questions framed. First, Hans Jonas s thinking on the ontology of life and the imperative of responsibility is studied. In Jonas s analysis modern culture is found to be nihilistic because it is unable to understand organic life, to find meaning in reality, and to justify morals. At the root of nihilism Jonas finds dualism, the traditional Western way of seeing consciousness as radically separate from the material world. Jonas attempts to create a metaphysical grounding for an ethic that would take the technologically increased human powers into account and make the responsibility for future generations meaningful and justified. The second approach is Albert Borgmann s philosophy of technology that mainly assesses the ways in which technological development has affected everyday life. Borgmann admits that modern technology has liberated humans from toil, disease, danger, and sickness. Furthermore, liberal democracy, possibilities for self-realization, and many of the freedoms we now enjoy would not be possible on a large scale without technology. Borgmann, however, argues that modern technology in itself does not provide a whole and meaningful life. In fact, technological conditions are often detrimental to the good life. Integrity in life, according to him, is to be sought among things and practices that evade technoscientific objectification and commodification. Larry Hickman s Deweyan philosophy of technology is the third approach under scrutiny. Central in Hickman s thinking is a broad definition of technology that is nearly equal to Deweyan inquiry. Inquiry refers to the reflective and experiential way humans adapt to their environment by modifying their habits and beliefs. In Hickman s work, technology consists of all kinds of activities that through experimentation and/or reflection aim at improving human techniques and habits. Thus, in addition to research and development, many arts and political reforms are technological for Hickman. He argues for recasting such distinctions as fact/value, poiesis/praxis/theoria, and individual/society. Finally, Hickman does not admit a categorical difference between ethics and technology: moral values and norms need to be submitted to experiential inquiry as well as all the other notions. This study mainly argues for an interdisciplinary approach to the ethics of technology. This approach should make use of the potentialities of the research traditions in applied ethics, the philosophy of technology, and the social studies on science and technology and attempt to overcome their limitations. This study also advocates an endorsement of mid-level ethics that concentrate on the practices, institutions, and policies of temporal human life. Mid-level describes the realm between the instantaneous and individualistic micro-level and the universal and global macro level.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

PROFESSION, PERSON AND WORLDVIEW AT A TURNING POINT A Study of University Libraries and Library Staff in the Information Age 1970 - 2005 The incongruity between commonly held ideas of libraries and librarians and the changes that have occurred in libraries since 2000 provided the impulse for this work. The object is to find out if the changes of the last few decades have penetrated to a deeper level, that is, if they have caused changes in the values and world views of library staff and management. The study focuses on Finnish university libraries and the people who work in them. The theoretical framework is provided by the concepts of world view (values, the concept of time, man and self, the experience of the supernatural and the holy, community and leadership). The viewpoint, framework and methods of the study place it in the area of Comparative Religion by applying the world view framework. The time frame is the information age, which has deeply affected Finnish society and scholarly communication from 1970 to 2005. The source material of the study comprises 30 life stories; somewhat more than half of the stories come from the University of Helsinki, and the rest from the other eight universities. Written sources include library journals, planning documents and historical accounts of libraries. The experiences and research diaries of the research worker are also used as source material. The world view questions are discussed on different levels: 1) recognition of the differences and similarities in the values of the library sphere and the university sphere, 2) examination of the world view elements, community and leadership based on the life stories, and 3) the three phases of the effects of information technology on the university libraries and those who work in them. In comparing the values of the library sphere and the university sphere, the appreciation of creative work and culture as well as the founding principles of science and research are jointly held values. The main difference between the values in the university and library spheres concerns competition and service. Competition is part of the university as an institution of research work. The core value of the library sphere is service, which creates the essential ethos of library work. The ethical principles of the library sphere also include the values of democracy and equality as well as the value of intellectual freedom. There is also a difference between an essential value in the university sphere, the value of autonomy and academic freedom on the one hand, and the global value of the library sphere - organizing operations in a practical and efficient way on the other hand. Implementing this value can also create tension between the research community and the library. Based on the life stories, similarities can be found in the values of the library staff members. The value of service seems to be of primary importance for all who are committed to library work and who find it interesting and rewarding. The service role of the library staff can be extended from information services provider to include the roles of teacher, listener and even therapist, all needed in a competitive research community. The values of democracy and equality also emerge fairly strongly. The information age development has progressed in three phases in the libraries from the 1960s onward. In the third phase beginning in the mid 1990s, the increased usage of electronic resources has set fundamental changes in motion. The changes have affected basic values and the concept of time as well as the hierarchies and valuations within the library community. In addition to and as a replacement for the library possessing a local identity and operational model, a networked, global library is emerging. The changes have brought tension both to the library communities and to the relationship between the university community and the library. Future orientation can be said to be the key concept for change; it affects where the ideals and models for operations are taken from. Future orientation manifests itself as changes in metaphors, changes in the model of a good librarian and as communal valuations. Tension between the libraries and research communities can arise if the research community pictures the library primarily as a traditional library building with a local identity, whereas the 21st century library staff and directors are affected by future orientation and membership in a networked library sphere, working proactively to develop their libraries.