72 resultados para Liikenne-ennusteet


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Tavoitteena on ollut selvittää Helsingin seudun pääväylien kapasiteetin riittävyys nykytilanteessa ja tulevaisuudessa, miten liikenteen ja kysynnän hallinnan keinoilla voidaan vaikuttaa kapasiteetin riittävyyteen ja mitkä ovat potentiaalisimmat keinot, missä lisäkaistojen tarve näyttää ilmeiseltä näistä keinoista ja joukkoliikenteen kehittämisestä huolimatta ja mitkä ajoneuvotyypit on tarkoituksenmukaista oikeuttaa lisäkaistojen käyttöön. Selvityksen tuloksena ehdotetaan lisäkaistojen rakentamista neljälle säteittäiselle pääväyläjaksolle vuoteen 2020 mennessä. Jaksot ovat kiireellisyysjärjestyksessä kt 51 (Länsiväylä) Piispansilta-Suomenoja (lännen suuntaan), vt 1 (Turunväylä) Tuomarila-Kehä II (molemmat suunnat), vt 3 (Hämeenlinnanväylä) Kaivoksela-Kannelmäki (molemmat suunnat) ja vt 4 (Lahdenväylä) Porvoonväylä- Kehä I (molemmat suunnat) + Porvoonväylän (vt 7) liittymäramppi Helsingin suuntaan. Lisäkaistojen yhteispituus on 12 km ja ne esitetään varattavaksi linja-autojen, kuorma-autojen ja pakettiautojen käyttöön ympärivuorokautisesti. Muilla, vuoteen 2035 ylikuormittuvaksi ennustetuilla pääväyläjaksoilla kapasiteetin riittävyys ehdotetaan varmistettavaksi ensisijaisesti liikenteen ja kysynnän hallinnan keinoin. Näitä ylikuormittuvaksi ennustettuja väyläjaksoja on yhteensä noin 70 ajoratakilometrin verran. Pääväylien liikenteen kasvua hillitään kehittämällä raideliikennettä ja liityntäpysäköintiä sekä liityntäpysäköinnin opastus- ja informaatiojärjestelmien avulla. Merkittävillä uusilla maankäytön kasvualueilla tieliikenteen kasvua hillitään kytkemällä maankäytön ja liikennejärjestelmän kehittäminen toisiinsa ja pyrkimällä liikennekysyntää vähentävään toiminnalliseen yhdyskuntarakenteeseen. Seudun pääväylille ehdotetaan vaihtuvia nopeusrajoituksia. Ruuhkatilanteissa nopeusrajoituksia lasketaan erityisesti liikenneturvallisuuden parantamiseksi, mutta rajoitusten alentaminen myös lieventää liikennevirran shokkiaaltoja ja parantaa siten kriittisesti kuormittuneen väylän välityskykyä. Ruuhkaliikenteen nopeuden alentuminen leikkaa myös tieliikennemelun huippuja. Ensimmäisiksi vaihtuvien nopeusrajoitusten toteutuskohteiksi esitetään Turunväylän (vt 1) ja Lahdenväylän (vt 4) ehdotettuja lisäkaistajaksoja. Vaihtuvaan nopeusrajoitusjärjestelmään ja liityntäpysäköinnin opastus- ja informaatiojärjestelmään ehdotetaan liitettäväksi myös ajoradan yläpuolisten varoitusmerkkien ja tekstiopasteiden yhdistelmiä, joiden avulla voidaan tiedottaa mm. liikenteen häiriöistä.

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ELY-keskuksen laaja yleisesite.

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Asiakkaat ovat pääosin tyytyväisiä ELY-keskusten tarjoamaan palveluun ja annettuja arvosanoja voidaan pitää erittäin hyvinä. ELY-keskusten valtakunnalliset keskimääräiset tyytyväisyysarvosanat ovat pysyneet käytännössä ennallaan edellisvuoden tutkimukseen nähden. Tätä voidaan pitää erittäin positiivisena huomioiden ELY-keskuksiin kohdistuneet sopeuttamistoimet ja niiden toimintaympä-ristössä tapahtuneet muutokset vuoden 2015 Vuoden 2015 palvelutyytyväisyystutkimuksessa oli mukana ELY-keskusten rahoitus-, maksatus-, lupa- ja valvontapalvelut. Lisäksi erillisenä tutkimuskohteena mukana oli ensimmäistä kertaa yritysten kehittämispalvelut (analyysi-, konsultointi- sekä koulutuspalvelut). Tutkimukseen osallistui kaikki ELY-keskukset lukuun ottamatta Lapin ja Pohjois-Pohjanmaan ELY-keskuksia, joiden osalta palvelutyy-tyväisyyskyselyitä ei tehty vuoden 2015 aikana. Vastauksia tutkimukseen saatiin yhteensä lähes 3500 kappaletta. ELY-keskusten asiakkailta saamien ”palvelu kokonaisuudessaan” tyytyväisyysarvosanojen valtakunnallinen keskiarvo on kaikkien pal-veluiden osalta yli neljä (4,10) eli tyytyväisyys oli laskenut hienoisesti vuoden 2014 tuloksista (4,13). Asiakkaat ovat antaneet korkeim-mat tyytyväisyysarvosanat ”asiantuntemuksesta” sekä ”ystävällisyydestä”. Muita tekijöitä alhaisemmat arvosanat on annettu ”asian käsittelynopeudelle”. Rahoituspalveluiden osalta kokonaisarvosana (3,98) on laskenut hivenen. Koettu palvelun ystävällisyys on pysynyt korkealla tasolla, mutta tyytyväisyys käsittelynopeuteen on laskenut. Maksatuspalveluiden osalta kokonaisarvosana (4,16) on pysynyt ennallaan ja tyyty-väisyys käsittelynopeuteen on parantunut. Lupapalveluiden osalta kokonaisarvosana (4,17) on pysynyt ennallaan. Sen sijaan asiakkai-den tyytyväisyys asiantuntemukseen, ystävällisyyteen ja päätösten perusteluihin on laskenut selvästi. Lupapalveluiden muutokset nä-kyvät kaikkien vastaajien kokonaistuloksessa. Valvontapalveluiden osalta kokonaisarvosana (3,99) on laskenut hivenen. Yrityspalvelujen analyysi- ja konsultointipalveluissa parhaaksi koettiin mm. palvelun nopea ja vaivaton saatavuus sekä suora hyöty liiketoimintaan. Koulutuspalvelut taas saivat kiitosta sisällöistä ja koulutusten läpiviennistä. Sekä konsultointipalvelut että avainhenki-löille suunnatut koulutusohjelmat koettiin tehokkaaksi tavaksi kehittää yrityksen toimintaa. Asiakkaat odottavat sujuvaa asiointia ELY-keskuksen kanssa. Yhä useammalle asiakkaalle tämä tarkoittaa hyvin toimivia sähköisiä palveluita. Keskeiset asiakkaiden esille nostamat kehityskohteet liittyivät asioinnin koettuun työläyteen, prosessin monimutkaisuuteen tai vaikeuteen. Lisäksi hitaaksi koettu asian käsittelynopeus sai osakseen kritiikkiä. Nopeasti kasvava sähköinen asiointi tarvitsee tuek-seen hyvin saavutettavan monikanavaisen asiakaspalvelun, jonka edelleen kehittämiseen tulee panostaa. Lisätietoja tutkimuksen koordinointiin liittyvissä asioista saa Teija Junttilalta KEHA-keskuksesta.

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A population-based early detection program for breast cancer has been in progress in Finland since 1987. According to regulations during the study period 1987-2001, free of charge mammography screening was offered every second year to women aged 50-59 years. Recently, the screening service was decided to be extended to age group 50-69. However, the scope of the program is still frequently discussed in public and information about potential impacts of mass-screening practice changes on future breast cancer burden is required. The aim of this doctoral thesis is to present methodologies for taking into account the mass-screening invitation information in breast cancer burden predictions, and to present alternative breast cancer incidence and mortality predictions up to 2012 based on scenarios of the future screening policy. The focus of this work is not on assessing the absolute efficacy but the effectiveness of mass-screening, and, by utilizing the data on invitations, on showing the estimated impacts of changes in an existing screening program on the short-term predictions. The breast cancer mortality predictions are calculated using a model that combines incidence, cause-specific and other cause survival on individual level. The screening invitation data are incorporated into modeling of breast cancer incidence and survival by dividing the program into separate components (first and subsequent rounds and years within them, breaks, and post screening period) and defining a variable that gives the component of the screening program. The incidence is modeled using a Poisson regression approach and the breast cancer survival by applying a parametric mixture cure model, where the patient population is allowed to be a combination of cured and uncured patients. The patients risk to die from other causes than breast cancer is allowed to differ from that of a corresponding general population group and to depend on age and follow-up time. As a result, the effects of separate components of the screening program on incidence, proportion of cured and the survival of the uncured are quantified. According to the predictions, the impacts of policy changes, like extending the program from age group 50-59 to 50-69, are clearly visible on incidence while the effects on mortality in age group 40-74 are minor. Extending the screening service would increase the incidence of localized breast cancers but decrease the rates of non-localized breast cancer. There were no major differences between mortality predictions yielded by alternative future scenarios of the screening policy: Any policy change would have at the most a 3.0% reduction on overall breast cancer mortality compared to continuing the current practice in the near future.

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Tässä työssä selvitetään lentosääennusteiden käyttöä lennon suunnittelun ja toteutuksen perusteena. Tuodaan esille määräyksiä ja lentosäätietojen käyttöä kaikissa lennon vaiheissa. Perehdytään ennustettujen olosuhteiden ja ennusteiden laadun merkitykseen lentojen toteutuksessa. Selvitetään lentosääennusteisiin liittyviä lentoliikenteen kustannuksia. Työn aineistona käytettiin joulukuu 2006 - heinäkuu 2007 välisenä aikana eri pituisina jaksoina kerättyä 185 liikennelennon lennonsuunnittelumateriaalia ja 126 satunnaisella otoksella otettuja Suomen GAFOR -ennusteita. Liikennelennot toteutettiin Suomen ja Euroopan alueella. Työssä todennettiin METAR –lentopaikkasanoman avulla TAF -lentopaikka-, TREND -laskeutumis-, GAFOR -yleisilmailuennusteita. Yleisestä sääpalvelusta saatua materiaalia käsiteltiin EXCEL –taulukkolaskentaohjelmalla Lentosääennusteita käsiteltiin usean eri käyttäjäryhmän kannalta. Reittilentomittauksilla tutkittiin SIGMET –varoituspalvelun, SWC –merkitsevän sään ja yläilmakehän tuulen sekä lämpötilan ennusteita. TAF –pilvikorkeusennusteiden keskimääräinen hyvyysluku oli lähes sama pilvikorkeudesta riippumatta. Suhteellisen hyvissä olosuhteissa toimivat käyttäjät saivat ennusteista paljon hyötyä. Vaakanäkyvyysennusteiden keskimääräinen hyvyysluku oli suurempi hyvissä kuin huonoissa olosuhteissa. Huonojen olosuhteiden ennusteet olivat lentotoiminnalle enemmän harmillisia kuin hyödyllisiä. Ennustustyö olisi tarvinnut apuvälinettä. Tutkittiin TREND –ennusteiden ominaista osuvuutta. NOSIG –ennuste oli suhteellisen usein julkaistu vaikka sitä seurasi olosuhteen muutos. BECMG -ennuste toteutui pääsääntöisesti ennusteajan alkupuolella. Ajoittaisten olosuhdemuutosten aikana TEMPO -ennusteita julkaistiin hyvin, mutta ennusteen osuvuus vaihteli. Tässä muodossa jaettu ennustetieto ei palvele kovin hyvin päätöstilannetta, jossa on arvioitava polttoaineen riittävyys lennon loppuosalle. GAFOR -pintatuuliennusteet olivat onnistuneita kuten TAF -ennusteissa. Vaakanäkyvyys- ja pilvikorkeusolosuhteissa vertailupisteissä oli 10% havainnoista ennustettua huonompaa olosuhdetta, jos käytettiin vain GAFOR –ennusteen perusosaa lennonsuunnittelussa ja 6% havainnoista, jos käytettiin koko ennustetta. Ilma-aluksen päällikön on valvottava näkölento-olosuhteiden kehitystä lennon aikana ja varmistettava aina näkölento-olosuhteinen lentoreitti laskupaikalle. Lentosääennusteet ovat osa lentotoimintaa mahdollistavaa järjestelmää. Ennusteet hallitsevat vaihtelevasti olosuhteita ja luonnollisesti aiheuttavat ongelmallisia tilanteita. Käyttäjiä sitovat määräykset on luotu, jotta toiminta olisi turvallista. Laadukkaita ennusteita tarvitaan isoilla liikennepaikoilla lentoliikenteen kapasiteetin hallintaan. Pienillä lentopaikoilla laitevarustus ei vielä takaa lentotoimintaa kaikissa olosuhteissa. Näkölentotoimintaa harjoitetaan jatkuvasti sekä hyvissä että kohtalaisen huonoissa olosuhteissa.

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In technicolor theories the scalar sector of the Standard Model is replaced by a strongly interacting sector. Although the Standard Model has been exceptionally successful, the scalar sector causes theoretical problems that make these theories seem an attractive alternative. I begin my thesis by considering QCD, which is the known example of strong interactions. The theory exhibits two phenomena: confinement and chiral symmetry breaking. I find the low-energy dynamics to be similar to that of the sigma models. Then I analyze the problems of the Standard Model Higgs sector, mainly the unnaturalness and triviality. Motivated by the example of QCD, I introduce the minimal technicolor model to resolve these problems. I demonstrate the minimal model to be free of anomalies and then deduce the main elements of its low-energy particle spectrum. I find the particle spectrum contains massless or very light technipions, and also technibaryons and techni-vector mesons with a high mass of over 1 TeV. Standard Model fermions remain strictly massless at this stage. Thus I introduce the technicolor companion theory of flavor, called extended technicolor. I show that the Standard Model fermions and technihadrons receive masses, but that they remain too light. I also discuss flavor-changing neutral currents and precision electroweak measurements. I then show that walking technicolor models partly solve these problems. In these models, contrary to QCD, the coupling evolves slowly over a large energy scale. This behavior adds to the masses so that even the light technihadrons are too heavy to be detected at current particle accelerators. Also all observed masses of the Standard Model particles can be generated, except for the bottom and top quarks. Thus it is shown in this thesis that, excluding the masses of third generation quarks, theories based on walking technicolor can in principle produce the observed particle spectrum.

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Noble gases are mostly known as inert monatomic gases due to their limited reactivity with other elements. However, the first predictions of noble-gas compounds were suggested by Kossel in 1916, by von Antropoff in 1924, and by Pauling in 1930. It took many decades until the first noble-gas compound, XePtF6, was synthesized by Neil Bartlett in 1962. This was followed by gradual development of the field and many noble-gas compounds have been prepared. In 1995, a family of noble-gas hydride molecules was discovered at the University of Helsinki. These molecules have the general formula of HNgY, where H is a hydrogen atom, Ng is a noble-gas atom (Ar, Kr, or Xe), and Y is an electronegative fragment. The first molecular species made include HXeI, HXeBr, HXeCl, HKrCl and HXeH. Nowadays the total number of prepared HNgY molecules is 23 including both inorganic and organic compounds. The first and only neutral ground-state argon compound, HArF, was synthetized in 2000. Helium and neon are the only elements in the periodic table that do not form neutral, ground-state molecules. In this Thesis, experimental preparation of eight novel xenon- and krypton-containing organo-noble-gas hydrides made from acetylene (HCCH), diacetylene (HCCCCH) and cyanoacetylene (HCCCN) are presented. These novel species include the first organic krypton compound, HKrCCH, as well as the first noble-gas hydride molecule containing two Xe atoms, HXeCCXeH. Other new compounds are HXeCCH, HXeCC, HXeC4H, HKrC4H, HXeC3N, and HKrC3N. These molecules are prepared in noble-gas matrices (krypton or xenon) using ultraviolet photolysis of the precursor molecule and thermal mobilization of the photogenerated H atoms. The molecules were identified using infrared spectroscopy and ab initio calculations. The formation mechanisms of the organo-noble-gas molecules are studied and discussed in this context. The focus is to evidence experimentally the neutral formation mechanisms of HNgY molecules upon global mobility of H atoms. The formation of HXeCCXeH from another noble-gas compound (HXeCC) is demonstrated and discussed. Interactions with the surrounding matrix and molecular complexes of the HXeCCH molecule are studied. HXeCCH was prepared in argon and krypton solids in addition to a Xe matrix. The weak HXeCCH∙∙∙CO2 complex is prepared and identified. Preparation of the HXeCCH∙∙∙CO2 complex demonstrates an advanced approach to studies of HNgY complexes where the precursor complex (HCCH∙∙∙CO2) is obtained using photolysis of a larger molecule (propiolic acid).

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The Standard Model of particle physics consists of the quantum electrodynamics (QED) and the weak and strong nuclear interactions. The QED is the basis for molecular properties, and thus it defines much of the world we see. The weak nuclear interaction is responsible for decays of nuclei, among other things, and in principle, it should also effects at the molecular scale. The strong nuclear interaction is hidden in interactions inside nuclei. From the high-energy and atomic experiments it is known that the weak interaction does not conserve parity. Consequently, the weak interaction and specifically the exchange of the Z^0 boson between a nucleon and an electron induces small energy shifts of different sign for mirror image molecules. This in turn will make the other enantiomer of a molecule energetically favorable than the other and also shifts the spectral lines of the mirror image pair of molecules into different directions creating a split. Parity violation (PV) in molecules, however, has not been observed. The topic of this thesis is how the weak interaction affects certain molecular magnetic properties, namely certain parameters of nuclear magnetic resonance (NMR) and electron spin resonance (ESR) spectroscopies. The thesis consists of numerical estimates of NMR and ESR spectral parameters and investigations of the effects of different aspects of quantum chemical computations to them. PV contributions to the NMR shielding and spin-spin coupling constants are investigated from the computational point of view. All the aspects of quantum chemical electronic structure computations are found to be very important, which makes accurate computations challenging. Effects of molecular geometry are also investigated using a model system of polysilyene chains. PV contribution to the NMR shielding constant is found to saturate after the chain reaches a certain length, but the effects of local geometry can be large. Rigorous vibrational averaging is also performed for a relatively small and rigid molecule. Vibrational corrections to the PV contribution are found to be only a couple of per cents. PV contributions to the ESR g-tensor are also evaluated using a series of molecules. Unfortunately, all the estimates are below the experimental limits, but PV in some of the heavier molecules comes close to the present day experimental resolution.

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Recent epidemiological studies have shown a consistent association of the mass concentration of urban air thoracic (PM10) and fine (PM2.5) particles with mortality and morbidity among cardiorespiratory patients. However, the chemical characteristics of different particulate size ranges and the biological mechanisms responsible for these adverse health effects are not well known. The principal aims of this thesis were to validate a high volume cascade impactor (HVCI) for the collection of particulate matter for physicochemical and toxicological studies, and to make an in-depth chemical and source characterisation of samples collected during different pollution situations. The particulate samples were collected with the HVCI, virtual impactors and a Berner low pressure impactor in six European cities: Helsinki, Duisburg, Prague, Amsterdam, Barcelona and Athens. The samples were analysed for particle mass, common ions, total and water-soluble elements as well as elemental and organic carbon. Laboratory calibration and field comparisons indicated that the HVCI can provide a unique large capacity, high efficiency sampling of size-segregated aerosol particles. The cutoff sizes of the recommended HVCI configuration were 2.4, 0.9 and 0.2 μm. The HVCI mass concentrations were in a good agreement with the reference methods, but the chemical composition of especially the fine particulate samples showed some differences. This implies that the chemical characterization of the exposure variable in toxicological studies needs to be done from the same HVCI samples as used in cell and animal studies. The data from parallel, low volume reference samplers provide valuable additional information for chemical mass closure and source assessment. The major components of PM2.5 in the virtual impactor samples were carbonaceous compounds, secondary inorganic ions and sea salt, whereas those of coarse particles (PM2.5-10) were soil-derived compounds, carbonaceous compounds, sea salt and nitrate. The major and minor components together accounted for 77-106% and 77-96% of the gravimetrically-measured masses of fine and coarse particles, respectively. Relatively large differences between sampling campaigns were observed in the organic carbon content of the PM2.5 samples as well as the mineral composition of the PM2.5-10 samples. A source assessment based on chemical tracers suggested clear differences in the dominant sources (e.g. traffic, residential heating with solid fuels, metal industry plants, regional or long-range transport) between the sampling campaigns. In summary, the field campaigns exhibited different profiles with regard to particulate sources, size distribution and chemical composition, thus, providing a highly useful setup for toxicological studies on the size-segregated HVCI samples.

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Volatile organic compounds (VOCs) have a great influence on tropospheric chemistry; they affect ozone formation and they or their reaction products are able to take part in secondary organic aerosol formation; some of the VOCs are themselves toxic. Knowing the concentrations and sources of different reactive volatile organic compounds is essential for the development of ozone control strategies and for studies of secondary organic aerosol formation. The objective of this work was to study volatile organic compounds in urban air, develop and validate determination methods for them, characterize their concentrations and estimate the contributions of different VOC sources. Of the different compound groups detected in the urban air of Helsinki, alkanes were found to have the highest concentrations, but when the concentrations were scaled against the reactivity with hydroxyl radicals (OH), aromatic hydrocarbons and alkenes were found to have the greatest effect on local chemistry. Comparisons with rural sites showed that concentrations at Utö and Hyytiälä were generally lower than those in Helsinki, especially for the alkenes and aromatic hydrocarbons, but concentrations of halogenated hydrocarbons at Utö and carbonyls at Hyytiälä were at the same level as in Helsinki. Most halogenated hydrocarbons do not have any significant sources in Helsinki, and carbonyls are formed in the atmosphere in the reactions of other VOCs, and are therefore also produced in other than urban areas. At Hyytiälä carbonyls were found to have an important role in the local chemistry. The contribution of carbonyls as an OH sink was higher than that of the monoterpenes and aromatic hydrocarbons. Based on the emission profile and concentration measurements, the contributions of different sources were estimated at urban (Helsinki) and residential (Järvenpää) sites using a chemical mass balance (CMB) receptor model. It was shown that it is possible to apply CMB in the case of a large number of different compounds with different properties. According to the CMB analysis, the major sources for these VOCs in Helsinki were traffic and distant sources. At the residential site in Järvenpää, the contribution due to traffic was minor, while distant sources, liquid gasoline and wood combustion made higher contributions. It was also shown that wood combustion can be an important source at some locations of VOCs usually considered as traffic-related compounds (e.g., benzene).

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In this thesis, the kinetics of several alkyl, halogenated alkyl, and alkenyl free radical reactions with NO2, O2, Cl2, and HCl reactants were studied over a wide temperature range in time resolved conditions. Laser photolysis photoionisation mass spectrometer coupled to a flow reactor was the experimental method employed and this thesis present the first measurements performed with the experimental system constructed. During this thesis a great amount of work was devoted to the designing, building, testing, and improving the experimental apparatus. Carbon-centred free radicals were generated by the pulsed 193 or 248 nm photolysis of suitable precursors along the tubular reactor. The kinetics was studied under pseudo-first-order conditions using either He or N2 buffer gas. The temperature and pressure ranges employed were between 190 and 500 K, and 0.5 45 torr, respectively. The possible role of heterogeneous wall reactions was investigated employing reactor tubes with different sizes, i.e. to significantly vary the surface to volume ratio. In this thesis, significant new contributions to the kinetics of carbon-centred free radical reactions with nitrogen dioxide were obtained. Altogether eight substituted alkyl (CH2Cl, CHCl2, CCl3, CH2I, CH2Br, CHBr2, CHBrCl, and CHBrCH3) and two alkenyl (C2H3, C3H3) free radical reactions with NO2 were investigated as a function of temperature. The bimolecular rate coefficients of all these reactions were observed to possess negative temperature dependencies, while pressure dependencies were not noticed for any of these reactions. Halogen substitution was observed to moderately reduce the reactivity of substituted alkyl radicals in the reaction with NO2, while the resonance stabilisation of the alkenyl radical lowers its reactivity with respect to NO2 only slightly. Two reactions relevant to atmospheric chemistry, CH2Br + O2 and CH2I + O2, were also investigated. It was noticed that while CH2Br + O2 reaction shows pronounced pressure dependence, characteristic of peroxy radical formation, no such dependence was observed for the CH2I + O2 reaction. Observed primary products of the CH2I + O2 reaction were the I-atom and the IO radical. Kinetics of CH3 + HCl, CD3 + HCl, CH3 + DCl, and CD3 + DCl reactions were also studied. While all these reactions possess positive activation energies, in contrast to the other systems investigated in this thesis, the CH3 + HCl and CD3 + HCl reactions show a non-linear temperature dependency on the Arrhenius plot. The reactivity of substituted methyl radicals toward NO2 was observed to increase with decreasing electron affinity of the radical. The same trend was observed for the reactions of substituted methyl radicals with Cl2. It is proposed that interactions of frontier orbitals are responsible to these observations and Frontier Orbital Theory could be used to explain the observed reactivity trends of these highly exothermic reactions having reactant-like transition states.

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The development and changes in the distribution of herbivorous mammal communities during the Neogene is complex. The Eurasian scale environmental patterns reflect the large scale geographical and climatic patterns. The reorganization of these affect the biome distribution throughout the continent. The distribution of mammal taxa was closely associated with the distribution of biomes. In Eurasia the Neogene development of environments was twofold. The early and middle Miocene that seemed to have been advantageous for mammals was followed by drying of environments during the late Neogene. The mid-latitude drying was the main trend, and it is the combined result of the retreat of Paratethys, the uplift of Tibetan Plateau and changes in the ocean currents and temperatures. The common mammals were "driving" the evolution of mammalian communities. During the late Miocene we see the drying affecting more and more regions, and we see changes in the composition of mammalian communities.

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The tackling of coastal eutrophication requires water protection measures based on status assessments of water quality. The main purpose of this thesis was to evaluate whether it is possible both scientifically and within the terms of the European Union Water Framework Directive (WFD) to assess the status of coastal marine waters reliably by using phytoplankton biomass (ww) and chlorophyll a (Chl) as indicators of eutrophication in Finnish coastal waters. Empirical approaches were used to study whether the criteria, established for determining an indicator, are fulfilled. The first criterion (i) was that an indicator should respond to anthropogenic stresses in a predictable manner and has low variability in its response. Summertime Chl could be predicted accurately by nutrient concentrations, but not from the external annual loads alone, because of the rapid affect of primary production and sedimentation close to the loading sources in summer. The most accurate predictions were achieved in the Archipelago Sea, where total phosphorus (TP) and total nitrogen (TN) alone accounted for 87% and 78% of the variation in Chl, respectively. In river estuaries, the TP mass-balance regression model predicted Chl most accurately when nutrients originated from point-sources, whereas land-use regression models were most accurate in cases when nutrients originated mainly from diffuse sources. The inclusion of morphometry (e.g. mean depth) into nutrient models improved accuracy of the predictions. The second criterion (ii) was associated with the WFD. It requires that an indicator should have type-specific reference conditions, which are defined as "conditions where the values of the biological quality elements are at high ecological status". In establishing reference conditions, the empirical approach could only be used in the outer coastal water types, where historical observations of Secchi depth of the early 1900s are available. The most accurate prediction was achieved in the Quark. In the inner coastal water types, reference Chl, estimated from present monitoring data, are imprecise - not only because of the less accurate estimation method but also because the intrinsic characteristics, described for instance by morphometry, vary considerably inside these extensive inner coastal types. As for phytoplankton biomass, the reference values were less accurate than in the case of Chl, because it was possible to estimate reference conditions for biomass only by using the reconstructed Chl values, not the historical Secchi observations. An paleoecological approach was also applied to estimate annual average reference conditions for Chl. In Laajalahti, an urban embayment off Helsinki, strongly loaded by municipal waste waters in the 1960s and 1970s, reference conditions prevailed in the mid- and late 1800s. The recovery of the bay from pollution has been delayed as a consequence of benthic release of nutrients. Laajalahti will probably not achieve the good quality objectives of the WFD on time.    The third criterion (iii) was associated with coastal management including the resources it has available. Analyses of Chl are cheap and fast to carry out compared to the analyses of phytoplankton biomass and species composition; the fact which has an effect on number of samples to be taken and thereby on the reliability of assessments. However, analyses on phytoplankton biomass and species composition provide more metrics for ecological classification, the metrics which reveal various aspects of eutrophication contrary to what Chl alone does.