Digital repository of Slovenian research organisations

Search the repository
A+ | A- | Help | SLO | ENG

Query: search in
search in
search in
search in

Options:
  Reset


Query: "keywords" (factor analysis) .

1 - 6 / 6
First pagePrevious page1Next pageLast page
1.
Application of multivariate statistical methods for determining geochemical trends of elements on the territory of Slovenia
Robert Šajn, Mateja Gosar, Jasminka Alijagić, Tamara Teršič, 2024, original scientific article

Abstract: The main objective of this study is to map multi-element geochemical anomalies in soil on a regional scale. We aimed to determine and evaluate the baseline geochemical values and main geochemical trends in soil that may serve as reference values against any future changes. A total of 817 topsoil samples (0–10 cm) were collected in a 5 × 5 km grid and analyzed for 35 elements using ICP-ES after multi-acid digestions (HClO4/HNO3/HCl/HF) and 53 elements using ICP-MS after modified aqua regia digestion (HCl/HNO3/H2O). The analytical results for the two different digestion methods (multi-acid digestion vs. aqua regia) were also compared for each chemical element. Multivariate statistical methods were applied to identify the geochemical trends and main sources of trace elements over the territory of Slovenia. Based on these results, seven natural and one mixed natural/anthropogenic geochemical association were established. The contents and trends of the determined factors are presented according to 8 natural units, 4 drainage areas, and geological units characteristic of Slovenia. The identified anthropogenic geochemical association combines toxic elements (Ag, Bi, Cd, Hg, P, Pb, S, Sn, and Zn). Increased values of these elements can be found in mining areas and metallurgic centers, in Quaternary sediments of the Sava River, and Adriatic Basin as the consequence of past mining activities and in the Julian Alps, where their origin could be connected to the atmospheric deposition.
Keywords: soil, geochemical mapping, distribution of geochemical elements, factor analysis, cluster analysis
Published in DiRROS: 04.01.2024; Views: 187; Downloads: 46
.pdf Full text (9,92 MB)

2.
Measurements of bridge dynamic amplification factor using bridge weigh-in-motion data
Jan Kalin, Aleš Žnidarič, Andrej Anžlin, Maja Kreslin, 2022, original scientific article

Abstract: The dynamic component of bridge traffic loading is commonly taken into account with a Dynamic Amplification Factor (DAF)—the ratio between the dynamic and static load effects on a bridge. In the design codes, this factor is generally more conservative than in reality. Recently a new method of cal- culation of this factor had been developed. Data from 15 different bridges have been analysed since then and this paper presents the results of the analyses. The background for Bridge Weigh-in-Motion is given, and the most recent method for DAF calculation is described. The sites from which the data originated are presented, and the selection of data discussed. The results of the analyses are presented and discussed and some examples of DAF calculations are shown. Data from the considered sites have invariably demonstrated a DAF decrease with increasing axle load. This is a significant result, especially for assessment of existing structures, since it is beneficial to use measured structural param- eters to optimise structural analysis.
Keywords: bridge loads, bridge weigh-in-motion, dynamic amplication factor, dynamic analysis, measurement, traffic loading
Published in DiRROS: 14.07.2023; Views: 289; Downloads: 153
.pdf Full text (2,61 MB)
This document has many files! More...

3.
Private forest owner willingness to mobilise wood from dense, small-diameter tree stands
Matevž Triplat, Satu Helenius, Ruben Laina, Nike Krajnc, Thomas Kronholm, Zdenka Ženko, Teppo Hujala, 2023, original scientific article

Abstract: Forests are a source of renewable biomass, and their utilisation will play a vital role in the transition towards a climate-neutral economy. Small-diameter tree management could contribute to this transition via providing renewable biomass for sustainable uses and fostering tree growth towards long-lifecycle bioproducts. The utilisation of small-diameter trees in the EU is still low since new technologies and work models are required to make the operations economically profitable, environmentally sound, and socially attractive. The supply of biomass from small-diameter tree stands is dependent on forest owners with diverse perceptions on their forests and diverse ownership objectives. However, there is scarce research on forest owner perceptions on small-diameter tree management, which encompasses home consumption, self-active work, and commercial forestry services. A survey in four EU countries was designed to identify the main factors affecting the motivation of forest owners to mobilise biomass from small-diameter stands. Factor and clustering analyses were used to identify four forest owner segments: weakly-engaged traders, well-being seekers, self-active profit-seekers, and well-informed service users. The willingness to utilise biomass from small-diameter tree stands and participate in the market was shaped by forest owner knowledge of forestry, economic and socio-cultural motivations, and sensitivity to service offerings. Forest owner preferences for market participation are heterogenous, and thus different policy implementation approaches are needed and proposed.
Keywords: customer profiles, factor analysis, forestry services, management objectives, biomass, communication strategies
Published in DiRROS: 05.01.2023; Views: 630; Downloads: 250
.pdf Full text (1,51 MB)
This document has many files! More...

4.
Expression of FGFR1-4 in malignant pleural mesothelioma tissue and corresponding cell lines and its relationship to patient survival and FGFR inhibitor sensitivity
Gregor Vlačić, Mir Alireza Hoda, Thomas Klikovits, Katharina Sinn, Elisabeth Gschwandtner, Katja Mohorčič, Karin Schelch, Christine Pirker, Barbara Peter-Vörösmarty, Jelena Brankovic, Tanja Čufer, Aleš Rozman, Izidor Kern, 2019, original scientific article

Abstract: Malignant pleural mesothelioma (MPM) is a devastating malignancy with limited therapeutic options. Fibroblast growth factor receptors (FGFR) and their ligands were shown to contribute to MPM aggressiveness and it was suggested that subgroups of MPM patients could benefit from FGFR-targeted inhibitors. In the current investigation, we determined the expression of all four FGFRs (FGFR1-FGFR4) by immunohistochemistry in tissue samples from 94 MPM patients. From 13 of these patients, we were able to establish stable cell lines, which were subjected to FGFR1-4 staining, transcript analysis by quantitative RT-PCR, and treatment with the FGFR inhibitor infigratinib. While FGFR1 and FGFR2 were widely expressed in MPM tissue and cell lines, FGFR3 and FGFR4 showed more restricted expression. FGFR1 and FGFR2 showed no correlation with clinicopathologic data or patient survival, but presence of FGFR3 in 42% and of FGFR4 in 7% of patients correlated with shorter overall survival. Immunostaining in cell lines was more homogenous than in the corresponding tissue samples. Neither transcript nor protein expression of FGFR1-4 correlated with response to infigratinib treatment in MPM cell lines. We conclude that FGFR3 and FGFR4, but not FGFR1 or FGFR2, have prognostic significance in MPM and that FGFR expression is not suffcient to predict FGFR inhibitor response in MPM cell lines.
Keywords: malignant pleural mesothelioma, fibroblast growth factor receptors, azbestos, immunotherapy, chemotherapy, genomic analysis, infigratinib
Published in DiRROS: 07.10.2020; Views: 12088; Downloads: 1006
.pdf Full text (1,74 MB)
This document has many files! More...

5.
Multicenter evaluation of the fully automated PCR-based Idylla EGFR Mutation Assay on formalin-fixed, paraffin-embedded Q1 tissue of human lung cancer
Solène M. Evrard, Estelle T. Clermont, Isabelle Rouquette, Samuel Murray, Sebastian Dintner, Yun-Chung Nam-Apostolopoulos, Beatriz Bellosillo, Mar V. Rodriguez, Ernest Nadal, Klaus H. Wiedorn, Mitja Rot, Izidor Kern, 2019, original scientific article

Abstract: Before initiating treatment of advanced nonesmall-cell lung cancer with tyrosine kinase inhibitors (eg, erlotinib, gefitinib, osimertinib, and afatinib), which inhibit the catalytic activity of epidermal growth factor receptor (EGFR), clinical guidelines require determining the EGFR mutational status for activating (EGFR exons 18, 19, 20, or 21) and resistance (EGFR exon 20) mutations. The EGFR resistance mutation T790M should be monitored at cancer progression. The Idylla EGFR Mutation Assay, performed on the Idylla molecular diagnostics platform, is a fully automated (<2.5 hours turnaround time) sample-to-result molecular test to qualitatively detect 51 EGFR oncogene point mutations, deletions, or insertions. In a 15- center evaluation, Idylla results on 449 archived formalin-fixed, paraffin-embedded tissue sections, originating from nonesmall-cell lung cancer biopsies and resection specimens, were compared with data obtained earlier with routine reference methods, including next-generation sequencing, Sanger sequencing, pyrosequencing, mass spectrometry, and PCR-based assays. When results were discordant, a third method of analysis was performed, when possible, to confirm test results. After confirmation testing and excluding invalids/errors and discordant results by design, a concordance of 97.6% was obtained between Idylla and routine test results. Even with <10 mm2 of tissue area, a valid Idylla result was obtained in 98.9% of the cases. The Idylla EGFR Mutation Assay enables sensitive detection of most relevant EGFR mutations in concordance with current guidelines, with minimal molecular expertise or infrastructure.
Keywords: non-small cell lung carconima -- diagnosis -- genetics, ErbB receptors, sequence analysis, tyrosine kinase inhibitors, epidermal growth factor receptor
Published in DiRROS: 07.10.2020; Views: 1361; Downloads: 965
.pdf Full text (714,24 KB)
This document has many files! More...

6.
Trace elements and nitrogen content in naturally growing moss Hypnum cupressiforme in urban and peri-urban forests of the Municipality of Ljubljana (Slovenia)
S. Berisha, Mitja Skudnik, Urša Vilhar, M. Saboljević, Saša Zavadlav, Zvonka Jeran, 2017, original scientific article

Abstract: We monitored trace metals and nitrogen using naturally growing moss Hypnum cupressiforme Hedw. in urban and peri-urban forests of the City Municipality of Ljubljana. The aim of this study was to explore the differences in atmospheric deposition of trace metals and nitrogen between urban and peri-urban forests. Samples were collected at a total of 44 sites in urban forests (forests within the motorway ring road) and peri-urban forests (forests outside the motorway ring road). Mosses collected in urban forests showed increased trace metal concentrations compared to samples collected from peri-urban forests. Higher values were significant for As, Cr, Cu, Hg, Mo, Ni, Pb, Sb, Tl and V. Within the motorway ring road, the notable differences in element concentrations between the two urban forests were significant for Cr, Ni and Mo. Factor analysis showed three groups of elements, highlighting the contribution of traffic emissions, individual heating appliances and the resuspension of contaminated soils and dust as the main sources of trace elements in urban forests.
Keywords: heavy metals, biomonitoring, Ljubljana, ICP-MS, elemental analysis, factor analysis, traffic emissions
Published in DiRROS: 12.07.2017; Views: 3118; Downloads: 1159
.pdf Full text (2,38 MB)
This document has many files! More...

Search done in 0.15 sec.
Back to top