1531. Contaminant trends in urban groundwater: case study from Ljubljana (central Slovenia)Janja Svetina, Joerg Prestor, Brigita Jamnik, Primož Auersperger, Mihael Brenčič, 2024, original scientific article Abstract: Urban areas can significantly alter the quality status of aquifers if appropriate strategies to prevent and detect groundwater contamination are not implemented in time. The prevention of groundwater contamination should be a priority due to its potential long-term impact on the environment and the high cost of remediation. For effective and sustainable groundwater management, it is crucial to proactively monitor a wide range of compounds to prevent their spread, progression and increasing concentrations. This study is one of the few to analyse the trends of various urban groundwater contaminants (nitrate, sulphate, hexavalent chromium, pesticides, PCE and TCE) from a groundwater management perspective. Characteristic trends are assessed using linear regression and the Mann–Kendall method, while significant changes in trends are determined using the Darken and Pettitt tests. The time span of the analysed trends covers the transition period before and after the implementation of the Water Framework Directive (2000/60/EC) and the Groundwater Directive (2000/60/EC). This study confirms the effectiveness of enforcement measures to protect groundwater quality, as evidenced by several statistically significant decreasing trends. On the other hand, this study emphasises the importance of intervention-targeted sampling campaigns and the reporting of raw analytical values according to the ISO 11843 series of standards. This approach is essential to detect upward trends in emerging contaminants at an early stage and prevent them from reaching levels that could negatively impact the economy or even jeopardise the safety of drinking water supplies. Keywords: groundwater contamination, contaminant trends, groundwater management, urban aquifer, Ljubljansko polje Published in DiRROS: 25.03.2024; Views: 364; Downloads: 159
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1532. Effect of post-treated low-temperature plasma nitriding on the wear and corrosion resistance of 316L stainless steel manufactured by laser powder-bed fusionMatjaž Godec, Črtomir Donik, Aleksandra Kocijan, Bojan Podgornik, Danijela Anica Skobir Balantič, 2020, original scientific article Keywords: austenitic stainless steel, powder bed fusion, low-temperature plasma nitriding, wear and corrosion behaviour, dislocation cell structure Published in DiRROS: 25.03.2024; Views: 343; Downloads: 207
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1533. Međuodnos svojstava rasta i kvalitete drva na pokusnoj plohi arišaMirzeta Memišević Hodžić, Sulejman Sinanović, Dalibor Ballian, 2023, original scientific article Abstract: Larch (Larix decidua) showed good growth and adaptability to ecological conditions in Bosnia and Herzegovina. The research aims to determine the variability of the morphological traits of larch in the seed stand near Kakanj, the variability at the beginning of heartwood formation, and correlations among these properties.In the larch seed stand, established by seedlings 2+0 in 1979, an area of 0,45 hectares was set aside. The heights and breast height diameters of the trees were on that area were measured in 2002 and 2020, and the basal area and volume were calculated. In 2020, the trees were drilled at breast height with a Presler drill to measure the proportion of heartwood. Average values of all properties for 2002 and 2020 were calculated. The ten, five and one best trees were selected according to the properties of breast height diameter, height, basal area, volume, and the intensities of selection for these traits were calculated. The Pearson correlation coefficient among all investigated traits were calculated. The average breast height diameter of 41-year-old trees was 24,6 cm, average height 21,8 m, basal area 0.0499m2 and volume 0.3745 m3 (table 1), while in 2002. the average breast height diameter was 15,5 cm, height 18,2 m, basal area 0,020 m2, and volume 0,128 m3 (table 1). Between 2002 and 2020, there was an overtaking of trees in breast height diameter and height and thus the base and volume (table 2). The average larch tree starts heartwood formation at the age of 14 years (table 1). The earliest heart-wood formation occurs in the sixth year (tree 495) and the latest in the 32nd year (table 4). Pearson coefficient showed a high positive correlation between breast height diameter and height in 2002 (ta-ble 9), which means that trees with a good height increase also have a good thickness increase. As a result, the correlation between breast height diameter and basal area and breast height diameter and volume, height and basal area, height and volume, and basal area and volume are statistically signifi-cant. Pearson’s correlation coefficient for the year 2020 showed a negative correlation between the be-ginning of heartwood formation and all other traits (table 10), i.e., trees that formed heartwood earlier have higher values of growth traits.The results will be used in the selection processes of larch individuals with good height and thickness growth and early heartwood formation. Keywords: European larch, morphological properties, core formation, selection Published in DiRROS: 25.03.2024; Views: 378; Downloads: 245
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1534. Can a forest tree species progeny trial serve as an ex situ collection? : A case study on Alnus glutinosaRita Verbylaite, Filipos Aravanopoulos, Virgilijus Baliuckas, Aušra Juškauskaite, Dalibor Ballian, 2023, original scientific article Abstract: Scientifically informed decisions for the long-term conservation of extant genetic diversity should combine in situ and ex situ conservation methods. The aim of the present study was to assess if a progeny plantation consisting of several open pollinated (OP) families and established for breeding purposes can also serve as an ex situ conservation plantation, using the case study of a Lithuanian progeny trial of Alnus glutinosa, a keystone species of riparian ecosystems that warrants priority conservation actions. We employed 17 nuclear microsatellite (Simple Sequence Repeat) markers and compared the genetic diversity and copy number of the captured alleles of 22 OP progeny families from this plantation, with 10 wild A. glutinosa populations, originating from the two provenance regions of the species in Lithuania. We conclude that the progeny plantation could be used as an ex situ plantation for the A. glutinosa populations from the first provenance region (represented by eight genetic conservation units (GCU)). Based on the present study’s results, we can expect that the A. glutinosa progeny plantation harbors enough genetic diversity of wild A. glutinosa populations from the first provenance region. This progeny plantation can serve as a robust ex situ collection containing local alleles present in at least one wild population with at least 0.05 frequency with 25 replications. Keywords: black alder, genetic diversity, allele pattern, microsatellite genotypes, ex situ collection Published in DiRROS: 25.03.2024; Views: 375; Downloads: 163
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1535. Use of plasma nitriding to improve the wear and corrosion resistance of 18Ni-300 maraging steel manufactured by selective laser meltingMatjaž Godec, Bojan Podgornik, Aleksandra Kocijan, Črtomir Donik, Danijela Anica Skobir Balantič, 2021, original scientific article Keywords: selective laser melting, 18Ni-300 maraging steel, heat treatment, plasma nitriding, retained and reverted austenite, wear and corrosion behaviour Published in DiRROS: 25.03.2024; Views: 365; Downloads: 159
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1536. Pedunculate oak (Quercus robur L.) in Bosnia and Herzegovina - state and perspectivesMirzeta Memišević Hodžić, Dalibor Ballian, 2023, original scientific article Abstract: Bosnia and Herzegovina is located in Southeast Europe, and more than half its area of 51.129 km² belongs to forests and forest lands. 93% of the forests of Bosnia and Herzegovina are natural forests and have many plant species, many of which are endemic. There are eight oak species growing in Bosnia and Herzegovina. The most important ones are Quercus robur (despite being almost extinct due to overexploitation during the late XIX and early XX century), and Quercus petraea. Pedunculate oak in Bosnia and Herzegovina is found in mixed stands with common hornbeam and in pure stands under exceptional conditions, with a total area of about 30,000 ha. In this paper, the data of the studies carried out in the pedunculate oak forests of Bosnia and Herzegovina were compiled and a general evaluation was made. The results of phenological observation in pedunculate oak provenance test in Bosnia and Herzegovina through the years showed statistically significant differences among provenances in the beginning, end and duration of individual phenological phases. Researches on growth showed overtaking of provenances through the years, and best results in provenance Jelah for the most of investigated years. The research results on showed a significant positive correlation between the height and root collar diameter in provenance test and most of the investigated .The remaining pedunculate oak populations in Bosnia and Herzegovina have a good genetic structure and can be used as a seed stands for collecting seed material and producing seedlings for afforestation with this species Keywords: Pedunculate oak, Bosnia and Herzegovina, afforestation Published in DiRROS: 25.03.2024; Views: 343; Downloads: 207
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1537. How does day-to-day stress appraisal relate to coping among office workers in academia? : an ecological momentary assessment studyStephanie Hulin, Larissa Bolliger, Junoš Lukan, Anneleen Caluwaerts, Rosalie De Neve, Mitja Luštrek, Dirk De Bacquer, Els Clays, 2023, original scientific article Abstract: Existing literature indicates that academic staff experience increasing levels of work stress. This study investigated associations between day-to-day threat and challenge appraisal and day-to-day problem-focused coping, emotion-focused coping, and seeking social support among academic office workers. This study is based on an Ecological Momentary Assessment (EMA) design with a 15-working day data collection period utilising our self-developed STRAW smartphone application. A total of 55 office workers from academic institutions in Belgium (n = 29) and Slovenia (n = 26) were included and 3665 item measurements were analysed. Participants were asked approximately every 90 min about their appraisal of stressful events (experienced during the working day) and their coping styles. For data analysis, we used an unstructured covariance matrix in our linear mixed models. Challenge appraisal predicted problem-focused coping and threat appraisal predicted emotion-focused coping. Our findings suggest an association between threat appraisal as well as challenge appraisal and seeking social support. Younger and female workers chose social support more often as a coping style. While working from home, participants were less likely to seek social support. The findings of our EMA study confirm previous research on the relationship between stress appraisal and coping with stress. Participants reported seeking social support less while working from home compared to working at the office, making the work location an aspect that deserves further research. Keywords: academic setting, coping, work stress Published in DiRROS: 25.03.2024; Views: 313; Downloads: 51
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1538. Hardware–software co-design of an audio feature extraction pipeline for machine learning applicationsJure Vreča, Ratko Pilipović, Anton Biasizzo, 2024, original scientific article Abstract: Keyword spotting is an important part of modern speech recognition pipelines. Typical contemporary keyword-spotting systems are based on Mel-Frequency Cepstral Coefficient (MFCC) audio features, which are relatively complex to compute. Considering the always-on nature of many keyword-spotting systems, it is prudent to optimize this part of the detection pipeline. We explore the simplifications of the MFCC audio features and derive a simplified version that can be more easily used in embedded applications. Additionally, we implement a hardware generator that generates an appropriate hardware pipeline for the simplified audio feature extraction. Using Chisel4ml framework, we integrate hardware generators into Python-based Keras framework, which facilitates the training process of the machine learning models using our simplified audio features. Keywords: FPGA, MFCC, keyword spotting, chisel Published in DiRROS: 25.03.2024; Views: 470; Downloads: 454
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1540. MicroRNAs and long non-coding RNAs : prospects in diagnostics and therapy of cancerNina Hauptman, Damjan Glavač, 2013, published scientific conference contribution Abstract: Background. Non-coding RNAs (ncRNAs) are key regulatory molecules in cellular processes, and are potentialbiomarkers in many diseases. Currently, microRNAs and long non-coding RNAs are being pursued as diagnostic andprognostic biomarkers, and as therapeutic tools in cancer, since their expression profiling is able to distinguish differentcancer types and classify their sub-types.Conclusions. There are numerous studies confirming involvement of ncRNAs in cancer initiation, development andprogression, but have only been recently identified as new diagnostic and prognostic tools. This can be beneficialin future medical cancer treatment options, since ncRNAs are natural antisense interactors included in regulationof many genes connected to survival and proliferation. Research is directed in development of useful markers fordiagnosis and prognosis in cancer and in developing new RNA-based cancer therapies, of which some are alreadyin clinical trials. Keywords: microRNAs, long non-coding RNAs, biomarker Published in DiRROS: 22.03.2024; Views: 336; Downloads: 213
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