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Theory and Application of Linear Regression Models with Box-Cox Transformations
No full textThis thesis investigates the theoretical framework and applied methodology of linear regression models incorporating Box-Cox transformations, with a focus on improving model performance and interpretability in real-world data analysis. It is motivated by the challenge of modeling agricultural outcomes, particularly the relationship between soil nutrient concentrations and corn yield. Traditional linear regression models often struggle with data that violate assumptions of normality, linearity, and homoscedasticity. To address these limitations, Box-Cox transformations are applied to both the response and explanatory variables to stabilize variance, normalize residuals, and improve the linear structure of the data.
The empirical analysis of the thesis is based on a dataset comprising 215 field observations from a geographically distributed agricultural field. The analysis develops and compares several regression models, starting with a baseline model using untransformed variables and progressively incorporating Box-Cox transformed response and predictor variables. Variable selection is guided by stepwise procedures aimed at identifying parsimonious models that balance goodness-of-fit with model simplicity. Model evaluation relies on diagnostic plots and residual analysis to assess assumptions and performance.
This thesis emphasizes the practical value of transformation techniques, particularly the Box-Cox method in enhancing linear regression models for agricultural data. The approach improves adherence to statistical assumptions, enables more reliable inference, and increases predictive accuracy. These findings have broader implications for researchers and practitioners working with complex, non-normal data in applied fields such as agronomy, environmental science, and resource management
An integrative framework to combine migratory connectivity and demographic data
No full textMigratory species experience various conditions and events throughout their annual cycle that influence their spatial and demographic dynamics. To understand these dynamics, it is essential to describe the origin and destination of individuals. Migratory connectivity, which is defined as the geographic linkage between populations across the annual cycle, is increasingly incorporated in population models to relate population trends to environmental variables at different stages of the cycle. However, such information on migratory movements is obtained independently from the study of population dynamics despite the interaction between both processes. Expanding on the growing use of integrated modelling approaches, we developed an integrated framework that allows the sharing of information between migratory connectivity and population data. We first assembled an integrated migratory connectivity model and an integrated population model to join the analysis of GPS, live-reencounter, dead-recovery, capture–mark–recapture, and population count data within a unified framework. Based on simulated data, we assessed the ability of the resulting integrated connectivity and population model to produce unbiased and precise connectivity and demographic estimates. We then applied the same assessment to real data using the Eurasian Curlew (Numenius arquata) as a case study. On simulated data, the integrated connectivity and population model estimated connectivity and survival parameters with no bias and similar precision to the connectivity model alone. However, it outperformed the population model in estimating fecundity in the absence of explicit productivity data. When applied to the Eurasian Curlew, the integrated connectivity and population model produced overall similar migratory connectivity and more accurate demographic estimates than the connectivity model alone, consistent with previous studies. Additionally, the model was able to estimate fecundity, whereas the data were too sparse for the population model alone to disentangle juvenile survival and fecundity. The sharing of information between migratory connectivity and population data improved the estimation of demographic parameters by the population model and improved connectivity parameter estimates when data were scarce. This flexible framework can be generalised to include diverse data on migration movements, population structure, individual heterogeneity or environmental variables, allowing further investigation of the interaction between migration patterns and population dynamics.Peer reviewe
Global Methane Budget 2000–2020
No full textUnderstanding and quantifying the global methane (CH4) budget is important for assessing realistic pathways to mitigate climate change. CH4 is the second most important human-influenced greenhouse gas in terms of climate forcing after carbon dioxide (CO2), and both emissions and atmospheric concentrations of CH4 have continued to increase since 2007 after a temporary pause. The relative importance of CH4 emissions compared to those of CO2 for temperature change is related to its shorter atmospheric lifetime, stronger radiative effect, and acceleration in atmospheric growth rate over the past decade, the causes of which are still debated. Two major challenges in quantifying the factors responsible for the observed atmospheric growth rate arise from diverse, geographically overlapping CH4 sources and from the uncertain magnitude and temporal change in the destruction of CH4 by short-lived and highly variable hydroxyl radicals (OH). To address these challenges, we have established a consortium of multidisciplinary scientists under the umbrella of the Global Carbon Project to improve, synthesise, and update the global CH4 budget regularly and to stimulate new research on the methane cycle. Following Saunois et al. (2016, 2020), we present here the third version of the living review paper dedicated to the decadal CH4 budget, integrating results of top-down CH4 emission estimates (based on in situ and Greenhouse Gases Observing SATellite (GOSAT) atmospheric observations and an ensemble of atmospheric inverse-model results) and bottom-up estimates (based on process-based models for estimating land surface emissions and atmospheric chemistry, inventories of anthropogenic emissions, and data-driven extrapolations). We present a budget for the most recent 2010–2019 calendar decade (the latest period for which full data sets are available), for the previous decade of 2000–2009 and for the year 2020.
The revision of the bottom-up budget in this 2025 edition benefits from important progress in estimating inland freshwater emissions, with better counting of emissions from lakes and ponds, reservoirs, and streams and rivers. This budget also reduces double counting across freshwater and wetland emissions and, for the first time, includes an estimate of the potential double counting that may exist (average of 23 Tg CH4 yr−1). Bottom-up approaches show that the combined wetland and inland freshwater emissions average 248 [159–369] Tg CH4 yr−1 for the 2010–2019 decade. Natural fluxes are perturbed by human activities through climate, eutrophication, and land use. In this budget, we also estimate, for the first time, this anthropogenic component contributing to wetland and inland freshwater emissions. Newly available gridded products also allowed us to derive an almost complete latitudinal and regional budget based on bottom-up approaches.
For the 2010–2019 decade, global CH4 emissions are estimated by atmospheric inversions (top-down) to be 575 Tg CH4 yr−1 (range 553–586, corresponding to the minimum and maximum estimates of the model ensemble). Of this amount, 369 Tg CH4 yr−1 or ∼ 65 % is attributed to direct anthropogenic sources in the fossil, agriculture, and waste and anthropogenic biomass burning (range 350–391 Tg CH4 yr−1 or 63 %–68 %). For the 2000–2009 period, the atmospheric inversions give a slightly lower total emission than for 2010–2019, by 32 Tg CH4 yr−1 (range 9–40). The 2020 emission rate is the highest of the period and reaches 608 Tg CH4 yr−1 (range 581–627), which is 12 % higher than the average emissions in the 2000s. Since 2012, global direct anthropogenic CH4 emission trends have been tracking scenarios that assume no or minimal climate mitigation policies proposed by the Intergovernmental Panel on Climate Change (shared socio-economic pathways SSP5 and SSP3). Bottom-up methods suggest 16 % (94 Tg CH4 yr−1) larger global emissions (669 Tg CH4 yr−1, range 512–849) than top-down inversion methods for the 2010–2019 period. The discrepancy between the bottom-up and the top-down budgets has been greatly reduced compared to the previous differences (167 and 156 Tg CH4 yr−1 in Saunois et al. (2016, 2020) respectively), and for the first time uncertainties in bottom-up and top-down budgets overlap. Although differences have been reduced between inversions and bottom-up, the most important source of uncertainty in the global CH4 budget is still attributable to natural emissions, especially those from wetlands and inland freshwaters.
The tropospheric loss of methane, as the main contributor to methane lifetime, has been estimated at 563 [510–663] Tg CH4 yr−1 based on chemistry–climate models. These values are slightly larger than for 2000–2009 due to the impact of the rise in atmospheric methane and remaining large uncertainty (∼ 25 %). The total sink of CH4 is estimated at 633 [507–796] Tg CH4 yr−1 by the bottom-up approaches and at 554 [550–567] Tg CH4 yr−1 by top-down approaches. However, most of the top-down models use the same OH distribution, which introduces less uncertainty to the global budget than is likely justified.
For 2010–2019, agriculture and waste contributed an estimated 228 [213–242] Tg CH4 yr−1 in the top-down budget and 211 [195–231] Tg CH4 yr−1 in the bottom-up budget. Fossil fuel emissions contributed 115 [100–124] Tg CH4 yr−1 in the top-down budget and 120 [117–125] Tg CH4 yr−1 in the bottom-up budget. Biomass and biofuel burning contributed 27 [26–27] Tg CH4 yr−1 in the top-down budget and 28 [21–39] Tg CH4 yr−1 in the bottom-up budget.
We identify five major priorities for improving the CH4 budget: (i) producing a global, high-resolution map of water-saturated soils and inundated areas emitting CH4 based on a robust classification of different types of emitting ecosystems; (ii) further development of process-based models for inland-water emissions; (iii) intensification of CH4 observations at local (e.g. FLUXNET-CH4 measurements, urban-scale monitoring, satellite imagery with pointing capabilities) to regional scales (surface networks and global remote sensing measurements from satellites) to constrain both bottom-up models and atmospheric inversions; (iv) improvements of transport models and the representation of photochemical sinks in top-down inversions; and (v) integration of 3D variational inversion systems using isotopic and/or co-emitted species such as ethane as well as information in the bottom-up inventories on anthropogenic super-emitters detected by remote sensing (mainly oil and gas sector but also coal, agriculture, and landfills) to improve source partitioning
Kaikkea ei pidä säilyttää ikuisesti – asianajotoimiston arkiston analogisen aineiston seulontaprosessi ja säilytysaikoihin vaikuttavat lait ja asetukset
No full textTämä maisterintutkielma käsittelee hävitettävien ja säilytettävien aineistojen käsittelyä asianajotoimistossa; miten aineistoa kuuluisi hävittää, mitä tässä tulisi ottaa huomioon ja mikä rooli aineiston käsittelijällä prosessissa on. Tarkastelu keskittyy erityisesti asiakirjojen seulontavaiheeseen. Lähestyn kuvattua yksityisorganisaatioita sitovien normien kautta. Tutkimuskohteen on innoittanut opiskeluaikanani suorittamani harjoittelu asianajotoimistossa.
Keskeisinä säännöksinä työssä esiintyy tietosuojalaki, henkilötietolaki ja EU:n yleinen tietosuoja-asetus. Työssä tarkastellaan alan termistöä ja asiakirjojen oikeudellista luonnetta. Käsittelyn oikeaoppisuuden kautta selvennän, mikä merkitys tällä on yksityisorganisaation luotettavuuden yksityisorganisaatioiden toimien todistettavuuden oikeellisuuden kannalta. Tekstissä esittelen asianajotoimistolle laatimani asiakirjahallinnan ja/tai arkistoinnin parissa työskentelevän “ohjekirjan”, joka keskittyy tarkemmin asianajotoimistoissa tyypillisimmin esiintyviin asiakirjojen säilyttämistä koskeviin kysymyksiin.
Lainopillisen puolen lisäksi käsittelen sitä, miten yksityisorganisaatioiden hoitama asiakirjahallintoa käsitellään asiakirjahallinnon ammattilehti Failissa esiintyvissä artikkeleissa, puheenvuoroissa ja kolumneissa. Esittelen kirjoituksia, joissa käsitellään sitä, mitä ongelmakohtia alan ammattilaiset näkevät asiakirjahallinnon nykytilassa ja mitä toimia tämän ongelman ratkaisuksi tulisi tehdä. Peilaan näitä omaan kokemukseeni asiakirjahallinnan seulontaprosessia hoitaneena projektiharjoittelijana. Kokonaisuutena tutkielma muodostaa tekstin, jossa nousee esille asiakirjojen käsittelyn oikeaoppisuuden merkitys niin organisaatioille kuin ihmisille, jotka ovat käsiteltävien aineistojen takana.
Initial Care Pathway in Acute Heart Failure From Home to Hospital
No full textIntroduction: The prognosis of acute heart failure (AHF) remains poor. Studies focusing on the time-sensitivity of early AHF management have reported controversial results. Thus, our aim is to review current studies focusing on AHF patients using emergency medical services (EMS), their early management, and patient outcomes. Methods: We searched the recent literature in PubMed and Scopus for studies comparing AHF patients arriving at the hospital by EMS to those self-presenting (non-EMS) at ED (emergency department) from database inception until November 2022. Results: The literature search found five studies fulfilling our inclusion criteria. The percentage of AHF patients using EMS varied in these studies: 11.5% (100/873) in Finnish FINN-AKVA II, 22.1% (236/1068) in Canadian ASCEND-HF, 35.5% (5129/14454) in a Pakistan Heart Failure-registry study, 52.8% (3224/6106) in Spanish SEMICA, and 61.8% (309/500) in the European EURODEM study. The pre-hospital management differed across the reviewed studies. The use of NIV was rare, ranging from zero to four percent. Vasodilators and diuretics were more commonly used. Although, the differences in the use were obvious (range from 7.1% to 22.0%, and 0.0% to 29.0% accordingly). Three of the studies reported significantly higher 30-day mortality among EMS patients compared to non-EMS patients: ranging from 5.6% versus 3.5%, p < 0.001% to 15.0% versus 6.9%, p < 0.001. Conclusion: The use of EMS, as well as pre-hospital management, varies between the international cohorts and registries. The pre-hospital AHF management is generally limited. Moreover, EMS patients tend to have worse outcomes compared to non-EMS patients.Peer reviewe
Rapid unimolecular reactions of acyl peroxy radicals : extending the structure-activity relationships
No full textAcyl peroxy radicals are especially efficient at forming organic accretion products in the troposphere, but they also have short lifetimes due to rapid unimolecular reactions. For this reason, we find it important to accurately represent the reactions of these species in structure-activity relationships estimating the unimolecular reactivity of atmospheric peroxy radicals. To address this, we performed multi-conformer transition state theory calculations to determine H-shift and ring closure reaction rates for aldehyde-substituted and unsaturated acyl peroxy radicals over a wide temperature range. Similar calculations were performed for enol-substituted peroxy radicals, which are also underrepresented in SAR models. As a results, we found that H-shifts from aldehyde groups are highly competitive, that ring closures are overwhelmingly the major atmospheric fate of unsaturated acyl peroxy radicals, and that H-shifts from Z-enols outcompete all other unimolecular and bimolecular reactions whenever they are possible. In conclusion, in extending the SAR models we have gained valuable insight on some of the most rapid reactions for any peroxy radicals in the atmosphere.Peer reviewe
Elevated levels of lipoprotein(a) and low-density lipoprotein cholesterol in familial hypercholesterolemia patients : is dual primary prevention already in sight?
No full textPeer reviewe
Gerontologian alan tutkimusartikkelisi lähdössä tieteelliseen lehteen? ‒ Pohdi näitä vielä hetki!
No full textWidespread trace bromine and iodine in remote tropospheric non-sea-salt aerosols
No full textReactive halogens catalytically destroy O3 and therefore affect (1) stratospheric O3 depletion and (2) the oxidative capacity of the troposphere. Reactive halogens also partition into the aerosol phase, but what governs halogen-aerosol partitioning is poorly constrained in models. In this work, we present global-scale measurements of non-sea-salt aerosol (nSSA) bromine and iodine taken during the NASA Atmospheric Tomography Mission (ATom). Using the Particle Analysis by Laser Mass Spectrometry instrument, we found that bromine and iodine are present in 8 %–26 % (interquartile range, IQR) and 12 %–44 % (IQR) of accumulation-mode nSSA, respectively. Despite being commonly found in nSSA, the concentrations of bromine and iodine in nSSA were low but potentially important, at 0.11–0.57 pmol mol−1 (IQR) and 0.04–0.24 pmol mol−1 (IQR), respectively. In the troposphere, we find two distinct sources of bromine and iodine for nSSA: (1) a primary source from biomass burning and (2) a pervasive secondary source. In the stratosphere, nSSA bromine and iodine concentrations increased with increasing O3 concentrations; however, higher concentrations of stratospheric nSSA bromine and iodine were found in organic-rich particles that originated in the troposphere. Finally, we compared our ATom nSSA iodine measurements to the global chemical transport model GEOS-Chem (Goddard Earth Observing System); nSSA bromine concentrations could not be compared because they were not tracked in the model. We found that the model compared well to our ATom nSSA iodine measurements in the background atmosphere but not in the marine boundary layer, biomass burning plumes, or stratosphere
Temporal Beta Diversity of Bacteria in Streams: Network Position Matters But Differently for Bacterioplankton and Biofilm Communities
No full textConcern about biodiversity loss has yielded a surge of studies on temporal change in α-diversity, whereas temporal β-diversity has gained less interest. We sampled bacterioplankton, biofilm, and riparian soil bacteria repeatedly across the open-water season in a pristine stream network to determine the level of temporal β-diversity in relation to stream network position and environmental variability. We tested the hypothesis that aquatic bacterial communities in isolated and environmentally heterogenous headwaters exhibit high temporal β-diversity while the better-connected and environmentally more stable mainstem sections support more stable communities, and soil communities bear no relationship to network position. As expected, temporal β-diversity decreased from headwaters toward mainstems for bacterioplankton. Against expectations, an opposite pattern was observed for biofilm. For bacterioplankton, temporal β-diversity was positively related to temporal variability in water chemistry. For biofilm bacteria, temporal variability was negatively related to variability in temperature. Temporal β-diversity of soil communities did not show any response to stream network position, but was strongly related to variability in the soil environment. The two aquatic habitats and riparian soils supported distinctly different bacterial communities. The number of ASVs shared between the soil and the aquatic communities decreased along the network, and more so for bacterioplankton. The higher temporal variability of bacterial communities in the headwaters likely results from temporally variable input of propagules from riparian soil, emphasizing the role of land–water connection and network position to bacterioplankton community composition. Overall, bacterial communities exhibited high temporal variability, highlighting the importance of temporal replication to fully capture their network-scale biodiversity