Search results for " AI"
showing 10 items of 2441 documents
Autochthonous organic matter promotes DNRA and suppresses N2O production in sediments of the coastal Baltic Sea
2021
Coastal environments are nitrogen (N) removal hot spots, which regulate the amount of land-derived N reaching the open sea. However, mixing between freshwater and seawater creates gradients of inorganic N and bioavailable organic matter, which affect N cycling. In this study, we compare nitrate reduction processes between estuary and offshore archipelago environments in the coastal Baltic Sea. Denitrification rates were similar in both environments, despite lower nitrate and carbon concentrations in the offshore archipelago. However, DNRA (dissimilatory nitrate reduction to ammonium) rates were higher at the offshore archipelago stations, with a higher proportion of autochthonous carbon. Th…
Periphyton as a key diet source of essential fatty acids for macroinvertebrates across a nutrient and dissolved organic carbon gradient in boreal lak…
2022
We studied how physiologically important long-chain polyunsaturated fatty acids (PUFA) in benthic macroinvertebrates (Asellus aquaticus, Chironomidae, and Oligochaeta) were related to those in periphyton and terrestrial organic matter (tree leaves), collected from littoral areas of 17 boreal lakes that differed in their dissolved organic carbon (DOC) and nutrient (phosphorus and nitrogen) concentrations. We also analyzed fatty acid (FA)-specific stable carbon isotopes (δ13CFA) to investigate the dietary origin (periphyton vs. terrestrial organic matter) of PUFA in the consumers. In contrast to periphyton, terrestrial organic matter was deprived of long-chain PUFA, such as eicosapentaenoic a…
Sunlit surface waters : exploring the photochemical reactivity of dissolved organic carbon
2017
In surface waters, solar radiation can photochemically mineralise the dissolved organic carbon (DOC, a measure of dissolved organic matter, DOM) to dissolved inorganic carbon (DIC). This DIC photoproduction constitutes an essential yet vague flux in the aquatic carbon cycling. The present thesis is based on the empirical assessment of the DOC photochemical reactivity, which was determined as the spectral apparent quantum yields (AQY) for DIC photoproduction. First, AQYs were determined in DOM solutions to quantify the impact of pH and DOM-associated iron. Then boreal lake waters were used for assessing the alteration of DOC photoreactivity due to water quality and catchment property. By sim…
Carbon Budget and Molecular Structure of Natural Organic Matter in Bank Infiltrated Groundwater
2021
Groundwater : : journal of the Association of Ground-Water Scientists and Engineers, a division of the National Ground Water Association (2021). doi:10.1111/gwat.13087
Coupling of iron and dissolved organic matter in lakes–selective retention of different size fractions
2023
AbstractIncreasing concentration of iron (Fe) is observed in many boreal lakes, such as for the present study in Oslo Østmark, SE-Norway (1983–2018). As Fe-regulating processes are complex and dynamic, the link between mobilizing and retention processes is still not well understood. A seasonal study (2017–2018) from two headwaters, with medium and high dissolved organic matter (DOM) concentrations, showed that the loading of Fe to the lakes was highly dependent on flow conditions. Significantly higher values of Fe were related to autumn and winter periods with high runoff of highly colored and aromatic DOM compared to a severe drought period with minimum Fe values in the lakes. Compared to …
Lojalitātes karšu izmantošana kopsakarā ar personas datu aizsardzības regulējumu.
2018
Mūsdienu ikdiena nav iedomāja bez lojalitātes programmām. Gandrīz katrs mazumtirdzniecības veikalu tīkls vai pakalpojumu sniedzējs ir ieviesis lojalitātes programmas, kas tiek plaši izmantotas personu vidū. 2018.gada 25. maijā spēkā stājas Eiropas Parlamenta un Padomes Regula (ES) 2016/679 (2016.gada 27.aprīlis) par fizisku personu aizsardzību attiecībā uz personas datu apstrādi un šādu datu brīvu apriti ar ko atceļ Direktīvu 95/46/EK (Vispārīgā datu aizsardzības regula), kas drīzāk traktējama kā datu aizsardzības evolūcija, nevis revolūcija kā tā pašlaik tiek pasniegta publiskajā telpā. Darba gaitā tiks noskaidrots vai lojalitātes programmas, kas ir mūsu ikdienas sastāvdaļa atbilst datu ai…
Preprocessing methods for nodule detection in lung CT
2005
Abstract The use of automatic systems in the analysis of medical images has proven to be very useful to radiologists, especially in the framework of screening programs, in which radiologists make their first diagnosis on the basis of images only, most of those corresponding to healthy patients, and have to distinguish pathological findings from non-pathological ones at an early stage. In particular, we are developing preprocessing methods to be applied for pulmonary nodule Computer Aided Detection in low-dose lung Multi Slice CT (computed tomography) images.
Technical note : Simulation of lung counting applications using Geant4
2023
A Geant4 simulation package has been developed to investigate and test detector configurations for lung counting applications. The objective of this study was to measure radiation emitted from the human body and to make a qualitative comparison of the results of the simulation with an experiment. Experimental data were measured from a plastic phantom with a set of lungs containing 241Am activity. For comparison, simulations in which 241Am activity was uniformly distributed inside the lungs of the ICRP adult reference computational phantom were made. The attenuation of photons by the chest wall was simulated and from this photopeak ef-ficiency and photon transmission were calculated as a fun…
Noninvasive Ventilation in Critically Ill Patients
2015
Since its first application in the late 1980s, noninvasive ventilation (NIV) has been the first-line intervention for certain forms of acute respiratory failure. NIV may be delivered through the patient's mouth, nose, or both using noninvasive intermittent positive pressure ventilation or continuous positive airway pressure. When applied appropriately, NIV may reduce morbidity and mortality and may avert iatrogenic complications and infections associated with invasive mechanical ventilation. This article provides physicians and respiratory therapists with a comprehensive, practical guideline for using NIV in critical care. © 2015 Elsevier Inc.
Līgumsoda piemērošanas prakse: samērīguma novērtējums, efektivitāte un nākotnes izredzes līgumsoda institūta likvidēšanai.
2021
Maģistra darba temats ir “Līgumsoda piemērošanas prakse: samērīguma novērtējums, efektivitāte un nākotnes izredzes līgumsoda institūta likvidēšanai”. Darba izvēle pamatota ar to, ka spēkā esošais līgumsoda regulējums ir nepietiekams, dažkārt, nonākot pretrunā ar civiltiesisko regulējumu kopumā. Darba mērķis ir izpētīt ar līgumsoda institūtu saistītos galvenos jautājumus, atzīmēt galvenās problēmas. Līdz ar to saprast, kādā veidā var uzlabot tiesisko regulējumu un izpētīt citus institūtus, kas spēj efektīvi pildīt līgumsoda funkcijas. Mērķa sasniegšanai tika izvirzīti uzdevumi izpētīt: 1)līgumsoda definīciju un vēsturisko attīstību; 2)funkcijas un samērīguma kritērijus; 3)aprēķināšanas kārtī…