974 resultados para WEIGHTED EARLINESS
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Background: Epidemiological evidence of the effects of long-term exposure to air pollu tion on the chronic processes of athero genesis is limited. Objective: We investigated the association of long-term exposure to traffic-related air pollu tion with subclinical atherosclerosis, measured by carotid intima media thickness (IMT) and ankle–brachial index (ABI). Methods: We performed a cross-sectional analysis using data collected during the reexamination (2007–2010) of 2,780 participants in the REGICOR (Registre Gironí del Cor: the Gerona Heart Register) study, a population-based prospective cohort in Girona, Spain. Long-term exposure across residences was calculated as the last 10 years’ time-weighted average of residential nitrogen dioxide (NO2) estimates (based on a local-scale land-use regression model), traffic intensity in the nearest street, and traffic intensity in a 100 m buffer. Associations with IMT and ABI were estimated using linear regression and multinomial logistic regression, respectively, controlling for sex, age, smoking status, education, marital status, and several other potential confounders or intermediates. Results: Exposure contrasts between the 5th and 95th percentiles for NO2 (25 μg/m), traffic intensity in the nearest street (15,000 vehicles/day), and traffic load within 100 m (7,200,000 vehicle-m/day) were associated with differences of 0.56% (95% CI: –1.5, 2.6%), 2.32% (95% CI: 0.48, 4.17%), and 1.91% (95% CI: –0.24, 4.06) percent difference in IMT, respectively. Exposures were positively associated with an ABI of > 1.3, but not an ABI of < 0.9. Stronger associations were observed among those with a high level of education and in men ≥ 60 years of age. Conclusions: Long-term traffic-related exposures were associated with subclinical markers of atherosclerosis. Prospective studies are needed to confirm associations and further examine differences among population subgroups.key words: ankle–brachial index, average daily traffic, cardiovascular disease, exposure assessment, exposure to tailpipe emissions, intima media thickness, land use regression model, Mediterranean diet, nitrogen dioxide
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The identification of biomarkers of vascular cognitive impairment is urgent for its early diagnosis. The aim of this study was to detect and monitor changes in brain structure and connectivity, and to correlate them with the decline in executive function. We examined the feasibility of early diagnostic magnetic resonance imaging (MRI) to predict cognitive impairment before onset in an animal model of chronic hypertension: Spontaneously Hypertensive Rats. Cognitive performance was tested in an operant conditioning paradigm that evaluated learning, memory, and behavioral flexibility skills. Behavioral tests were coupled with longitudinal diffusion weighted imaging acquired with 126 diffusion gradient directions and 0.3 mm(3) isometric resolution at 10, 14, 18, 22, 26, and 40 weeks after birth. Diffusion weighted imaging was analyzed in two different ways, by regional characterization of diffusion tensor imaging (DTI) indices, and by assessing changes in structural brain network organization based on Q-Ball tractography. Already at the first evaluated times, DTI scalar maps revealed significant differences in many regions, suggesting loss of integrity in white and gray matter of spontaneously hypertensive rats when compared to normotensive control rats. In addition, graph theory analysis of the structural brain network demonstrated a significant decrease of hierarchical modularity, global and local efficacy, with predictive value as shown by regional three-fold cross validation study. Moreover, these decreases were significantly correlated with the behavioral performance deficits observed at subsequent time points, suggesting that the diffusion weighted imaging and connectivity studies can unravel neuroimaging alterations even overt signs of cognitive impairment become apparent.
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We've developed a new ambient occlusion technique based on an information-theoretic framework. Essentially, our method computes a weighted visibility from each object polygon to all viewpoints; we then use these visibility values to obtain the information associated with each polygon. So, just as a viewpoint has information about the model's polygons, the polygons gather information on the viewpoints. We therefore have two measures associated with an information channel defined by the set of viewpoints as input and the object's polygons as output, or vice versa. From this polygonal information, we obtain an occlusion map that serves as a classic ambient occlusion technique. Our approach also offers additional applications, including an importance-based viewpoint-selection guide, and a means of enhancing object features and producing nonphotorealistic object visualizations
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The present study builds on a previous proposal for assigning probabilities to the outcomes computed using different primary indicators in single-case studies. These probabilities are obtained comparing the outcome to previously tabulated reference values and reflect the likelihood of the results in case there was no intervention effect. The current study explores how well different metrics are translated into p values in the context of simulation data. Furthermore, two published multiple baseline data sets are used to illustrate how well the probabilities could reflect the intervention effectiveness as assessed by the original authors. Finally, the importance of which primary indicator is used in each data set to be integrated is explored; two ways of combining probabilities are used: a weighted average and a binomial test. The results indicate that the translation into p values works well for the two nonoverlap procedures, with the results for the regression-based procedure diverging due to some undesirable features of its performance. These p values, both when taken individually and when combined, were well-aligned with the effectiveness for the real-life data. The results suggest that assigning probabilities can be useful for translating the primary measure into the same metric, using these probabilities as additional evidence on the importance of behavioral change, complementing visual analysis and professional's judgments.
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Budget forecasts have become increasingly important as a tool of fiscal management to influence expectations of bond markets and the public at large. The inherent difficulty in projecting macroeconomic variables – together with political bias – thwart the accuracy of budget forecasts. We improve accuracy by combining the forecasts of both private and public agencies for Italy over the period 1993-2012. A weighted combined forecast of the deficit/ ratio is superior to any single forecast. Deficits are hard to predict due to shifting economic conditions and political events. We test and compare predictive accuracy over time and although a weighted combined forecast is robust to breaks, there is no significant improvement over a simple RW model.
Resumo:
Budget forecasts have become increasingly important as a tool of fiscal management to influence expectations of bond markets and the public at large. The inherent difficulty in projecting macroeconomic variables – together with political bias – thwart the accuracy of budget forecasts. We improve accuracy by combining the forecasts of both private and public agencies for Italy over the period 1993-2012. A weighted combined forecast of the deficit/ ratio is superior to any single forecast. Deficits are hard to predict due to shifting economic conditions and political events. We test and compare predictive accuracy over time and although a weighted combined forecast is robust to breaks, there is no significant improvement over a simple RW model.
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Chironomidae spatial distribution was investigated at 63 near-pristine sites in 22 catchments of the Iberian Mediterranean coast. We used partial redundancy analysis to study Chironomidae community responses to a number of environmental factors acting at several spatial scales. The percentage of variation explained by local factors (23.3%) was higher than that explained by geographical (8.5%) or regional factors(8%). Catchment area, longitude, pH, % siliceous rocks in the catchment, and altitude were the best predictors of Chironomidae assemblages. We used a k-means cluster analysis to classified sites into 3 major groups based on Chironomidae assemblages. These groups were explained mainly by longitudinal zonation and geographical position, and were defined as 1) siliceous headwater streams, 2) mid-altitude streams with small catchment areas, and 3) medium-sized calcareous streams. Distinct species assemblages with associated indicator taxa were established for each stream category using IndVal analysis. Species responses to previously identified key environmental variables were determined, and optima and tolerances were established by weighted average regression. Distinct ecological requirements were observed among genera and among species of the same genus. Some genera were restricted to headwater systems (e.g., Diamesa), whereas others (e.g., Eukiefferiella) had wider ecological preferences but with distinct distributions among congenerics. In the present period of climate change, optima and tolerances of species might be a useful tool to predict responses of different species to changes in significant environmental variables, such as temperature and hydrology.
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Interactions of cationic dye methylene blue (MB) with clay particles in aqueous suspension have been extensively studied. As already known, the number of natural negative charges on the clay modifies significantly the particle sizes dispersed in water and therefore the nature of the interaction with the dye. This work evaluated with UV-Vis spectroscopy method how the clay particle sizes weighted on the adsorption and rearrangement of the dye molecules in aqueous system. The results obtained from light-scattering measurements confirmed that larger particles are found in suspensions containing the high-charged clays as the visible absorption band related to the MB aggregates (570 nm) on these suspensions prevailed.
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This thesis presents two graphical user interfaces for the project DigiQ - Fusion of Digital and Visual Print Quality, a project for computationally modeling the subjective human experience of print quality by measuring the image with certain metrics. After presenting the user interfaces, methods for reducing the computation time of several of the metrics and the image registration process required to compute the metrics, and details of their performance are given. The weighted sample method for the image registration process was able to signifigantly decrease the calculation times while resulting in some error. The random sampling method for the metrics greatly reduced calculation time while maintaining excellent accuracy, but worked with only two of the metrics.
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Tämä diplomityö on tehty IMMU-hankkeeseen, jossa selvitetään konkreettisia keinoja ilmastonmuutoksen hillintään Lahden seudulla. Diplomityössä tarkastellaan mahdollisuuksia lisätä biopolttoaineita pienen kokoluokan kaukolämmön tuotantolaitoksissa. Teoria osuuden pohjalta luodaan skenaariot Nastolaan ja Vääksyyn (Asikkala). Skenaarioissa tarkastellaan biopolttoaineiden lisäämisen vaikutuksia kasvihuonekaasu- ja hiukkaspäästöihin käyttämällä elinkaariarviointimenetelmää. Taloudellisia seikkoja tarkastellaan laskemalla takaisinmaksuaikoja eri biolaitosratkaisuille nettonykyarvomenetelmällä. Tutkimuksen tuloksena saatiin, että kasvihuonekaasupäästöt tuotannon elinkaaren ajalta vähenevät eniten tuottamalla kaukolämmön perustuotanto Nastolassa ja Vääksyssä bio-CHP-laitoksella haketta polttamalla. Kiinteitä biopolttoaineita poltettaessa tulevat kuitenkin suurimmat hiukkaspäästöt, mikä vaikuttaa asuinympäristön viihtyvyyteen tuotantolaitoksen läheisyydessä. Bio-CHP-laitoksen investointikustannukset ovat suurimmat ja takaisinmaksuaika pisin. Nastolan kulutusperusteisiä päästöjä pystytään vähentämään eniten investoimalla biolämpölaitokseen tai bio-CHP-laitokseen. Päästöjä Nastolassa pystyttäisiin kyseisillä investoinneilla vähentämään enimmillään 6,4 %. Lahti energian kokonaispäästöjä pystyttäisiin enimmillään vähentämään noin 1,6 %. Johtopäätöksenä tutkimuksesta voidaan sanoa, että kasvihuonekaasupäästöjä pystytään vähentämään investointien avulla. Toiset ratkaisut ovat vain kalliimpia kuin toiset. Lisäksi kiinteitä biopolttoaineita käytettäessä jotkut poltto-ominaisuudet voivat heiketä esim. verrattuna maakaasun polttoon. Biopolttoaineiden lisäämisellä kuitenkin päästään irti riippuvuudesta fossiilisiin polttoaineisiin kuten öljyyn ja maakaasuun. Investointeja tehdessä on vaikea sanoa suoraan, mikä vaihtoehto on paras tapa tuottaa kaukolämpöä. Investointipäätöksiä tehdessä päätökseen vaikuttaa se, mitä tuotannon ominaispiirteitä painotetaan eniten.
Resumo:
Tietotekniikan käyttö on tärkeää mikroyrityksen kasvun kannalta. Tutkielmassa pyrittiin toimintatutkimuksen keinoin löytämään kosmetiikan suoramyyntiä harjoittavan toiminimen KaunisSinä taustalla olevan osa-aikaisen yrittäjän asettamien tavoitteiden ja rajoitteiden mukaan paras ohjelmisto tukemaan asiakkuuden hallintaa. Ohjelmiston valintaa varten tutkittiin ohjelmistohankinnan menetelmiä kaupallisten valmisohjelmistojen, avoimen lähdekoodin ohjelmistojen ja räätälöityjen ohjelmistojen osalta. Yrittäjän toimintatapojen kartoituksen perusteella muodostettiin kriteerit ohjelmistojen vertailua ja valintaa varten. Vertailussa käytettiin painotetun keskiarvon menetelmää. Markkinoilla on saatavilla ominaisuuksiltaan sopivia avoimen lähdekoodin asiakkuuden hallintaohjelmistoja. Valinta on kompromissi ohjelmiston tarjoaman toiminnallisuuden sekä ominaisuuksien ja yritykselle muodostuneiden toimintatapojen välillä. Yrityksen on siis osittain mukautettava toimintatapojaan ohjelmiston mukaiseksi.
Resumo:
The deterioration of surface waters is one of the most important issues in the environmental management of the European Union. Thus, the EU Water Framework Directive 2000/60/EC (WFD) requires “good ecological and chemical status” of surface waters by 2015 allowing only a slight departure from ecological reference conditions characterized by the biological communities typical for the conditions of minimal anthropogenic impact. The WFD requires the determination of ecological reference conditions and the present ecological status of surface waters. To meet this legislative demand, sedimentary diatom assemblages were used in these studies with various methods 1) to assess natural and human activity induced environmental changes, 2) to characterize background conditions 3) to evaluate the present ecological status and 4) to predict the future of the water bodies in the light of palaeolimnological data. As the WFD refers to all surface waters, both coastal and inland sites were included. Two long and two short sediment cores from the Archipelago Sea in the northern Baltic Sea were examined for their siliceous microfossils in order to assess (1) the Holocene palaeoenvironmental history and (2) the recent eutrophication of the area. The diatom record was divided into local diatom assemblage zones (LDAZ, long cores) and diatom assemblage zones (DAZ, short cores). Locally weighted weighted averaging regression and calibration (LWWA) was applied for the quantitative reconstruction of past TN concentrations (short cores). An age model for the long cores was constructed by using independent palaeomagnetic and AMS-14C methods. The short cores were dated using radiometric (210Pb, 226Ra and 137Cs) methods. The long cores date back to the early history of the Archipelago Sea, which was freshwater – no salinity increase referable to the brackish phase of the Yoldia Sea is recognized. The nutrient status of the lacustrine phase was slightly higher in the Archipelago Sea than in the Baltic Proper. Initial brackish-water influence is observed at 8 150 ±80 cal. BP (LDAZ4), but fully brackish conditions were established at 7 700 ±80 cal. BP (LDAZ5). The diatom assemblages indicate increasing salinity, warming climate and possible eutrophic conditions during the lacustrine to brackish-water transition. The decreasing abundance of Pseudosolenia calcar-avis (Schultze) Sundström and the increasing abundance of the ice-cover indicator species Pauliella taeniata (Grunow) Round and Basson indicate decreasing salinity and climatic cooling after ca. 5 000 cal. BP. Signs of eutrophication are visible in the most recent diatom assemblage zones of both short cores. Diatom-inferred total nitrogen (DI-TN) reconstructions partially fail to trace the actual measured total nitrogen concentrations especially from the late 1980s to the mid 1990s. This is most likely due to the dominating diatom species Pauliella taeniata, Thalassiosira levanderi Van Goor and Fragilariopsis cylindrus (Grunow) W. Krieger being more influenced by factors such as the length of the ice-season rather than nutrient concentrations. It is concluded that the diatom assemblages of the study sites are principally governed by climate fluctuations, with a slight influence of eutrophication visible in the most recent sediments. There are indications that global warming, with reduced ice cover, could impact the spring blooming diatom species composition in the Archipelago Sea. In addition, increased sediment accumulation in the early 90s coincides with the short ice-seasons suggesting that warming climate with decreasing ice-cover may increase sedimentation in the study area. The diverse diatom assemblages dominated by benthic species (54 %) in DAZ1 in the Käldö Fjärd core can be taken as background diatom assemblages for the Archipelago Sea. Since then turbidity has increased and the diatom assemblages have been dominated by planktonic diatoms from around the mid 1800s onwards. The reconstructed reference conditions for the total nitrogen concentrations fluctuate around 400 μg l-1. Altogether two short sediment cores and eight short cores for top-bottom analysis were retrieved from Lake Orijärvi and Lake Määrjärvi to assess the impact of the acid mine drainage (AMD) derived metals from the Orijärvi mine tailings on the diatom communities of the lakes. The Cu (Pb, Zn) mine of Orijärvi (1757 – 1956) was the first one in Finland where flotation techniques (1911 – 1955) were used to enrich ore and large quantities of tailings were produced. The AMD derived metal impact to the lakes was found to be among the heaviest thus far recorded in Finland. Concentrations of Cu, Pb and Zn in Lake Orijärvi sediments are two to three orders of magnitude higher than background values. The metal inputs have affected Lake Orijärvi and Lake Määrjärvi diatom communities at the community levels through shifts in dominant taxa (both lakes) and at the individual level through alteration in frustule morphology (Lake Orijärvi). At present, lake water still has elevated heavy metal levels, indicating that the impact from the tailings area continues to affect both lakes. Lake Orijärvi diatom assemblages are completely dominated by benthic species and are lacking planktonic diatoms. In Lake Määrjärvi the proportion of benthic and tychoplanktonic diatoms has increased and the planktonic taxa have decreased in abundance. Achnanthidium minutissimum Kützing and Brachysira vitrea (Grun.) R. Ross in Hartley were the most tolerant species to increased metal concentrations. Planktonic diatoms are more sensitive to metal contamination than benthic taxa, especially species in the genus Cyclotella (Kützing) Brébisson. The ecological reference conditions assessed in this study for Lake Orijärvi and Lake Määrjärvi comprise diverse planktonic and benthic communitites typical of circumneutral oligotrophic lakes, where the planktonic diatoms belonging to genera Cyclotella , Aulacoseira Thwaites, Tabellaria Ehrenberg and Asterionella Hassall dominate in relative abundances up to ca. 70%. The benthic communities are more diverse than the planktonic consisting of diatoms belonging to the genera Achnanthes Bory, Fragilaria Lyngbye and Navicula St. Vincent. This study clearly demonstrates that palaeolimnological methods, especially diatom analysis, provide a powerful tool for the EU Water Frame Work Directive for defining reference conditions, natural variability and current status of surface waters. The top/bottom approach is a very useful tool in larger-scale studies needed for management purposes. This “before and after” type of sediment sampling method can provide a very time and cost effective assessment of ecological reference conditions of surface waters.
Resumo:
Tutkimuksen aiheena on toimittaja-arvioinnin kehittäminen. Tutkimuksen tavoitteena oli kehittää Nokian Renkaat Oyj:n käyttöön tarkoituksenmukainen menetelmä toimittaja-arviointiin. Tutkimuksessa käsitellään toimittaja-arvioinnin roolia hankintatoimessa, keskeisiä arviointikriteerejä, arviointimenetelmiä sekä arvioinnin kehittämisessä huomioitavia tekijöitä. Empiirisessä osiossa määritetään kohdeyrityksen toimittajien arviointikriteerit, luokitellaan toimittajat sekä kehitetään menetelmä toimittaja-arviointiin. Tutkimuksen lopputuloksena kehitettiin työkalu toimittaja-arviointiin kohdeyrityksen käyttöön. Työkalu koostuu kahdesta erillisestä osasta, jotka ovat toteutuneen suorituskyvyn arviointi sekä toimittaja-auditointi. Auditointia varten laadittiin kysymyskaavake. Molemmat arvioinnin osa-alueet sisältävät painotetun pisteytyksen.
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Tutkimuksen tavoitteena oli arvioida, miten tuottavuustietoa voidaan hyödyntää johtamisen tukena ja kuinka tuottavuustietoa tällä hetkellä hyödynnetään Etelä-Karjalan keskussairaalassa (EKKS). Tuottavuuden mittaamisessa hyödynnetään Terveyden- ja hyvinvoinnin laitoksen (THL) vuosittain julkaisemassa Hoito-toiminnan tuottavuus -tilastossa käytettävää tuottavuuden mittaamismenetelmää, jossa panoksina ovat sairaalan tai erikoisalan hoitotoiminnasta aiheutuneet kustannukset ja tuotoksina NordDRG-ryhmittelijän avulla painotetut hoitojaksot ja käynnit. Tutkimuksessa arvioitiin tuottavuuden mittaamiseen liittyvien mahdollisten virhetekijöiden vaikutusta sairaalan tuottavuuteen EKKS:n tapauksessa ja tämän perusteella tunnistettiin, miten THL:n julkaisemaa tuottavuustilastoa ja sisäistä tuottavuustietoa voidaan hyödyntää sairaalan johtamisen tukena. Pääasiallisena aineistona työssä käytettiin EKKS:n henkilöstön haastatteluja ja sairaalan taloudellisia raportteja sekä THL:n julkista ja julkaisematonta aineistoa. THL:n kehittämän hoitotoiminnan tuottavuuden mittaamismenetelmän havaittiin soveltuvan yksittäisen sairaalan käyttöön tietyin muutoksin. Vaadittavien muutosten lisäksi tutkimuksessa tunnistettiin taustatekijät, jotka THL:n tuottavuustilaston ja sisäisen tuottavuustiedon tulkitsijan tulee ottaa huomioon. EKKS:n tuottavuustietojen keruussa havaittiin kehittämiskohteita, joita paran-tamalla tuottavuustiedon luotettavuutta ja hyödynnettävyyttä voidaan edelleen kehittää. Tuottavuustiedon hyödyntämistä voidaan niin ikään edelleen kehittää EKKS:ssa.