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141.
Biomonitoring and assessment of toxic element contamination in floodplain sediments and soils using fluorescein diacetate (FDA) enzymatic activity measurements: evaluation of possibilities and limitations through the case study of the Drava River floodplain
Péter Szabó, Gyozo Jordan, Tamás Kocsis, Katalin Posta, Levente Kardos, Robert Šajn, Jasminka Alijagić, 2022, original scientific article

Abstract: The EU Water Framework Directive requires the monitoring and evaluation of surface water sediment quality based on the assessment of risk posed by contamination on the biotic receptors. Floodplain sediments are important receptors of potentially toxic element (PTE) contamination from the upstream catchment areas, and floodplains host climate-sensitive riverine ecosystems and fertile agricultural areas at the same time. This study investigates the effect of PTE contamination on microbial communities in floodplain sediments and soils using the fast, inexpensive and reliable fluorescein diacetate (FDA) method in order to estimate its applicability for sediment quality monitoring and preliminary toxicity-based risk assessment. Sediment and soil samples were collected from the actively flooded alluvial plain and the river terrace areas along a 130-km stretch of the large Drava River floodplain known to be widely contaminated by historical mining, smelting and the associated industry in the upstream Alpine region. Results of detailed data analysis show that the total microbial activity represented by the measured FDA values is related to PTE (As, Cu, Zn, Cd, Pb) concentrations, but this relationship shows significant heterogeneity and depends on the spatial location and on the soil properties such as organic matter content, dissolved salt and nutrient content, and it is specific to the toxic elements. Results show that some microbe species appear to be able to adapt to the elevated PTE concentrations in toxic soil micro-environments, over time. Despite the observed heterogeneity of microbial activity, the results revealed a breakpoint in the FDA dataset around the FDA = 3 FC (fluorescein concentration) value suggesting that microbial activity is controlled by thresholds.
Keywords: potentially toxic elements, fluorescein diacetate activity, heavy metals, contamination, biological activity
Published in DiRROS: 25.08.2022; Views: 677; Downloads: 209
.pdf Full text (6,23 MB)

142.
143.
Letošnje februarske cene žaganega lesa iglavcev za več kot polovico višje od lanskih februarskih cen
Špela Ščap, Peter Prislan, 2022, professional article

Keywords: žagan les, iglavci, cene
Published in DiRROS: 01.08.2022; Views: 708; Downloads: 217
.pdf Full text (2,76 MB)

144.
Different wood anatomical and growth responses in European beech (Fagus sylvatica L.) at three forest sites in Slovenia
Domen Arnič, Jožica Gričar, Jernej Jevšenak, Gregor Božič, Georg von Arx, Peter Prislan, 2021, original scientific article

Abstract: European beech (Fagus sylvatica L.) adapts to local growing conditions to enhance its performance. In response to variations in climatic conditions, beech trees adjust leaf phenology, cambial phenology, and wood formation patterns, which result in different treering widths (TRWs) and wood anatomy. Chronologies of tree ring width and vessel features [i.e., mean vessel area (MVA), vessel density (VD), and relative conductive area (RCTA)] were produced for the 1960%2016 period for three sites that differ in climatic regimes and spring leaf phenology (two early- and one late-flushing populations). These data were used to investigate long-term relationships between climatic conditions and anatomical features of four quarters of tree-rings at annual and intra-annual scales. In addition, we investigated how TRW and vessel features adjust in response to extreme weather events (i.e., summer drought). We found significant differences in TRW, VD, and RCTA among the selected sites. Precipitation and maximum temperature before and during the growing season were the most important climatic factors affecting TRW and vessel characteristics. We confirmed differences in climate-growth relationships between the selected sites, late flushing beech population at Idrija showing the least pronounced response to climate. MVA was the only vessel trait that showed no relationship with TRW or other vessel features. The relationship between MVA and climatic factors evaluated at intra-annual scale indicated that vessel area in the first quarter of tree-ring were mainly influenced by climatic conditions in the previous growing season, while vessel area in the second to fourth quarters of tree ring width was mainly influenced by maximum temperature and precipitation in the current growing season. When comparing wet and dry years, beech from all sites showed a similar response, with reduced TRW and changes in intra-annual variation in vessel area. Our findings suggest that changes in temperature and precipitation regimes as predicted by most climate change scenarios will affect tree-ring increments and wood structure in beech, yet the response between sites or populations may differ.
Keywords: Fagus sylvatica, wood anatomy, tracheograms, dendrochronology, intra specific plasticity
Published in DiRROS: 22.07.2022; Views: 587; Downloads: 388
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145.
Modelling seasonal dynamics of secondary growth in R
Jernej Jevšenak, Jožica Gričar, Sergio Rossi, Peter Prislan, 2022, original scientific article

Abstract: The monitoring of seasonal radial growth of woody plants addresses the ultimate question of when, how and why trees grow. Assessing the growth dynamics is important to quantify the effect of environmental drivers and understand how woody species will deal with the ongoing climatic changes. One of the crucial steps in the analyses of seasonal radial growth is to model the dynamics of xylem and phloem formation based on increment measurements on samples taken at relatively short intervals during the growing season. The most common approach is the use of the Gompertz equation, while other approaches, such as general additive models (GAMs) and generalised linear models (GLMs), have also been tested in recent years. For the first time, we explored artificial neural networks with Bayesian regularisation algorithm (BRNNs) and show that this method is easy to use, resistant to overfitting, tends to yield s-shaped curves and is therefore suitable for deriving temporal dynamics of secondary tree growth. We propose two data processing algorithms that allow more flexible fits. The main result of our work is the XPSgrowth() function implemented in the radial Tree Growth (rTG) R package, that can be used to evaluate and compare three modelling approaches: BRNN, GAM and the Gompertz function. The newly developed function, tested on intra-seasonal xylem and phloem formation data, has potential applications in many ecological and environmental disciplines where growth is expressed as a function of time. Different approaches were evaluated in terms of prediction error, while fitted curves were visually compared to derive their main characteristics. Our results suggest that there is no single best fitting method, therefore we recommend testing different fitting methods and selection of the optimal one.
Keywords: artificial neural networks, cambium, generalized additive model, Gompertz function, growing season, intra-annual time series
Published in DiRROS: 21.07.2022; Views: 519; Downloads: 338
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146.
Priporočila za zobozdravstveno obravnavo odraslih bolnikov z rakom glave in vratu v Sloveniji, zdravljenih z obsevanjem
Aleš Fidler, Aleksandar Aničin, Vojislav Didanovič, Tadej Dovšak, Boris Gašpirc, Aleš Grošelj, Andrej Kansky, Matic Koren, Jana Krapež, Hojka Kuralt, Marko Kuralt, Boštjan Lanišnik, Romana Mance Kristan, Jošt Pavčič, Luka Prodnik, Peter Pukl, Tadej Ostrc, Milan Kuhar, Eva Skalerič, Robert Šifrer, Valerija Skopec, Primož Strojan, 2022, original scientific article

Abstract: Priporočila za zobozdravstveno obravnavo bolnikov z rakom glave in vratu (RGV) v Sloveniji, zdravljenih z obsevanjem sledijo priporočilom The Royal College of Surgeons of England v sodelovanju z The British Society for Disability and Oral Health, dopolnjujejo Priporočila za obravnavo bolnikov z rakom glave in vratu v Sloveniji in hkrati upoštevajo obstoječe zmožnosti slovenskega zdravstvenega sistema. Namen priporočil je prepre-čevanje oz. zmanjšanje zapletov v ustni votlini, ki nastanejo zaradi obsevanja. Opredeljujejo način zobozdravstvene oskrbe pred, med in po zdravljenju raka na vseh treh nivojih zobozdra-vstvene oskrbe, kar zagotavlja njeno pravočasnost in dostopnost. Priporočila predstavljajo poenoteno mnenje vseh deležnikov na področju zobozdravstvene obravnave bolnikov z RGV v državi.
Keywords: onkologija, zobozdravstvena obravnava, obsevanje, ustna votlina, priporočila
Published in DiRROS: 14.07.2022; Views: 626; Downloads: 215
.pdf Full text (1,45 MB)

147.
148.
Patch testing with the European baseline series and 10 added allergens : single centre study of 748 patients
Mojca Bizjak, Katja Adamič, Nisera Bajrović, Renato Eržen, Maja Jošt, Peter Kopač, Mitja Košnik, Nika Lalek, Mihaela Zidarn, Dejan Dinevski, 2022, original scientific article

Abstract: Background. The European baseline series (EBS) of contact allergens is subject to change. An allergen is considered for inclusion when routine patch testing of patients with suspected contact dermatitis results in ≥ 0.5% prevalence rate. Objectives. We aimed to determine the frequency of sensitizations to 30 EBS allergens and 10 locally added allergens. Additionally, we assessed the strength and evolution of reactions to all tested allergens and co-reactivity of additional allergens. Methods. Patch testing with our baseline series of 40 allergens was done in 748 consecutive adults. Tests were applied to the upper back and removed by patients after 48 hours. Readings were done on day 3 (D3) and D6 or D7 (D6/7). Positive reactions fulfilled the criteria of at least one plus (+) reaction. Retrospective analysis was done. Results. Eight allergens not listed in the EBS had ≥ 0.5% prevalence rate (i.e., cocamidopropyl betaine, thiomersal, disperse blue mix 106/124, 2-bromo-2-nitropropane-1,3-diol, diazolidinyl urea, propylene glycol, Compositae mix II, and dexamethasone-21-phosphate), and 16.6% of positive reactions would have been missed without D6/7 readings. Conclusion. We propose further studies to evaluate whether cocamidopropyl betaine, disperse blue mix 106/124, 2-bromo-2-nitropropane-1,3-diol, diazolidinyl urea, and Compositae mix II need to be added to the EBS.
Keywords: allergy and immunology -- diagnosis, hypersensitivity -- diagnosis, skin tests, clinical epidemiology, baseline series, contact sensitization, patch tests, simultaneous reactivity
Published in DiRROS: 24.06.2022; Views: 612; Downloads: 220
URL Link to file

149.
Solid cancer patients achieve adequate immunogenicity and low rate of severe adverse events after SARS-CoV-2 vaccination
Urška Janžič, Urška Bidovec, Katja Mohorčič, Loredana Mrak, Nina Fokter Dovnik, Marija Ivanović, Maja Ravnik, Marina Čakš, Erik Škof, Jerneja Debeljak, Peter Korošec, Matija Rijavec, 2022, original scientific article

Abstract: Background: SARS-CoV-2 vaccination in cancer patients is crucial to prevent severe COVID-19 disease course. Methods: This study assessed immunogenicity of cancer patients on active treatment receiving mRNA-based SARS-CoV-2 vaccine by detection of anti-SARS-CoV-2 S1 IgG antibodies in serum, before, after the first and second doses and 3 months after a complete primary course of vaccination. Results were compared with healthy controls. Results: Of 112 patients, the seroconversion rate was 96%. A significant reduction in antibody levels was observed 3 months after vaccination in patients receiving immune checkpoint inhibitors versus control participants (p < 0.001). Adverse events were mostly mild. Conclusion: Immunogenicity after mRNA-based vaccine in cancer patients is adequate but influenced by the type of anticancer therapy. Antibody levels decline after 3 months, and thus a third vaccination is warranted.
Keywords: onkološko zdravljenje, imunogenost, osnovno cepljenje mRNA, čvrsti tumorji, anticancer treatment, immunogenicity, mRNA-based vaccination, solid cancer
Published in DiRROS: 24.06.2022; Views: 863; Downloads: 345
.pdf Full text (2,03 MB)

150.
Effect of hydroxychloroquine in hospitalized patients with Covid-19
Peter Horby, Marion Mafham, Martin J. Landray, 2020, original scientific article

Abstract: Background: Hydroxychloroquine and chloroquine have been proposed as treatments for coronavirus disease 2019 (Covid-19) on the basis of in vitro activity and data from uncontrolled studies and small, randomized trials. Methods: In this randomized, controlled, open-label platform trial comparing a range of possible treatments with usual care in patients hospitalized with Covid-19, we randomly assigned 1561 patients to receive hydroxychloroquine and 3155 to receive usual care. The primary outcome was 28-day mortality. Results: The enrollment of patients in the hydroxychloroquine group was closed on June 5, 2020, after an interim analysis determined that there was a lack of efficacy. Death within 28 days occurred in 421 patients (27.0%) in the hydroxychloroquine group and in 790 (25.0%) in the usual-care group (rate ratio, 1.09; 95% confidence interval [CI], 0.97 to 1.23; P = 0.15). Consistent results were seen in all prespecified subgroups of patients. The results suggest that patients in the hydroxychloroquine group were less likely to be discharged from the hospital alive within 28 days than those in the usual-care group (59.6% vs. 62.9%; rate ratio, 0.90; 95% CI, 0.83 to 0.98). Among the patients who were not undergoing mechanical ventilation at baseline, those in the hydroxychloroquine group had a higher frequency of invasive mechanical ventilation or death (30.7% vs. 26.9%; risk ratio, 1.14; 95% CI, 1.03 to 1.27). There was a small numerical excess of cardiac deaths (0.4 percentage points) but no difference in the incidence of new major cardiac arrhythmia among the patients who received hydroxychloroquine. Conclusions: Among patients hospitalized with Covid-19, those who received hydroxychloroquine did not have a lower incidence of death at 28 days than those who received usual care. (Funded by UK Research and Innovation and National Institute for Health Research and others; RECOVERY ISRCTN number, ISRCTN50189673; ClinicalTrials.gov number, NCT04381936.).
Keywords: Covid-19 -- drug therapy, hydroxychloroquine, chloroquine
Published in DiRROS: 30.05.2022; Views: 541; Downloads: 306
URL Link to file
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