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Query: "author" (Polona %C4%8Ci%C5%BEman-%C5%BDagar) .

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31.
Tree rings, wood density and climate–growth relationships of four Douglas-fir provenances in sub-Mediterranean Slovenia
Luka Krajnc, Jožica Gričar, Jernej Jevšenak, Polona Hafner, Robert Brus, 2022, original scientific article

Abstract: Tree rings, wood density and the climate–growth relationship of four Douglas-fir provenances were analysed separately for the juvenile and adult phases. Four provenances were selected from an existing IUFRO provenance trial planted in 1971 based on their diameter at breast height and vitality. Increment cores were extracted from individual trees, on which we measured tree-ring widths (RW), earlywood widths (EWW) and latewood widths (LWW). Wood density was assessed in standing trees using resistance drilling. The climate–growth correlations were calculated between provenance chronologies of RW, EWW, LWW and latewood share, and the day-wise aggregated Standardised Precipitation-Evapotranspiration Index (SPEI). The analysis was done separately for the juvenile and mature phases of growth. Provenances 1064 (Jefferson) and 1080 (Yelm) exhibited larger annual radial increments than provenances 1028 (Merrit) and 1089 (Cathlamet). The two provenances with the highest annual radial increment in the juvenile phase did not exhibit the same trend in the adult phase. In all provenances, RW, and consequently EWW and LWW, were wider in the juvenile than in adult phase. The share of latewood was in all cases higher in juvenile wood than in mature wood. All four provenances had similar wood densities in both analyzed growth phases. Our analysis showed that when selecting the most promising provenance for planting, possible changes in relative growth rate from the juvenile to adult phase need to be considered.
Keywords: Pseudotsuga menziesii, SPEI, juvenile phase, adult phase, latewood share, resistance drilling
Published in DiRROS: 21.11.2022; Views: 522; Downloads: 178
.pdf Full text (3,07 MB)
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32.
Ženske v gozdarstvu
Polona Hafner, Darja Stare, 2021, professional article

Keywords: gozdarstvo, gozdovi, ženske, lastnice gozdov, izobraževanje, zaposlenost
Published in DiRROS: 12.11.2022; Views: 462; Downloads: 155
.pdf Full text (6,52 MB)

33.
Rare earth elements and yttrium in cold mineral and thermal (~30-60 °C) waters from Tertiary aquifers in the Mura Basin, north-eastern Slovenia: a review
Polona Kralj, 2022, review article

Abstract: Cold mineral and thermal waters from Tertiary aquifers in the Mura Basin mainly belong to the Ca-(Mg)-(Na)-HCO3 and Na-HCO3 hydrogeochemical facies, respectively, and the concentrations of yttrium (Y) and lanthanides or rare earth elements (REEs) are far below (10-2 – 10-4) the abundances in the aquifer sediments. Mineral waters are high pCO2, and the plots of concentrations of YREEs normalised to Post Archean Australian Shale (PAAS) show fractionation of Y and heavy REEs (HREEs) over light REEs (LREEs), and a significant positive europium (Eu) anomaly. Thermal water from regionally developed aquifer Thermal I (recently also termed the Mura/Ujfalu Formation aquifer) shows a similar PAAS-normalised pattern with an obvious positive Eu anomaly and the tendency of enrichment with middle REEs (MREEs). The plots of PAAS-normalised YREE concentrations in thermal waters from the underlying low-permeability aquifers with poorly developed fracture porosity and abundant CO2 are flat with insignificant positive Eu anomaly. The abundance and fractionation of YREEs in mineral and thermal waters seems to be mainly controlled by the presence of carbonate complexing ligands, permeability of the aquifers and the related time of water-rock interaction.
Keywords: rare earth elements, Yttrium, mineral waters, thermal waters, well cycling, Mura Basin
Published in DiRROS: 27.07.2022; Views: 713; Downloads: 209
.pdf Full text (2,15 MB)

34.
Using stable isotopes and major ions to identify recharge characteristics of the Alpine groundwater-flow dominated Triglavska Bistrica River
Luka Serianz, Sonja Cerar, Polona Vreča, 2021, original scientific article

Abstract: Triglavska Bistrica is a typical Alpine river in the north-western part of Slovenia. Its recharge area includes some of the highest peaks in the Julian Alps. The hydrogeological conditions and flow of the river depend largely on groundwater exchange between the karstified aquifer in the carbonate rocks and the intergranular aquifer in the glaciofluvial deposits. The average volume of the river flow is up to several m3/s. In this study, water samples from different locations along the river were analysed for stable isotope ratios of oxygen and hydrogen, major ions, and concentration of tritium activity. The correlation of major ions suggests that the recharge area consists of both limestone and dolomite rocks. The δ18O and δ2H values decrease downstream, implying that the average recharge elevation increases. At the downstream sampling site V-5, located approx. 300 m upstream from the confluence of the Sava Dolinka River, the calculated mean recharge altitude is estimated to be 1,996 m.
Keywords: groundwater, oxygen and hydrogen isotopes, hydrogeochemistry, recharge area, Alpine aquifer, Slovenia
Published in DiRROS: 09.03.2022; Views: 953; Downloads: 306
.pdf Full text (3,01 MB)

35.
36.
Trajnostno gospodarjenje z gozdovi in trajnostna oskrba lesnopredelovalnih podjetij z lesom
Mitja Skudnik, Polona Hafner, 2021, preface, editorial, afterword

Published in DiRROS: 18.12.2021; Views: 862; Downloads: 256
.pdf Full text (46,36 KB)

37.
Robust saliva-based RNA extraction-free one-step nucleic acid amplification test for mass SARS-CoV-2 monitoring
Eva Rajh, Tina Šket, Arne Praznik, Petra Sušjan, Alenka Šmid, Dunja Urbančič, Irena Mlinarič-Raščan, Polona Kogovšek, Tina Demšar, Mojca Milavec, Katarina Prosenc, Žiga Jensterle, Mihaela Zidarn, Viktorija Tomič, Gabriele Turel, Tatjana Lejko-Zupanc, Roman Jerala, Mojca Benčina, 2021, original scientific article

Abstract: Early diagnosis with rapid detection of the virus plays a key role in preventing the spread of infection and in treating patients effectively. In order to address the need for a straightforward detection of SARS-CoV-2 infection and assessment of viral spread, we developed rapid, sensitive, extraction-free one-step reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and reverse transcription loop-mediated isothermal amplification (RT-LAMP) tests for detecting SARS-CoV-2 in saliva. We analyzed over 700 matched pairs of saliva and nasopharyngeal swab (NSB) specimens from asymptomatic and symptomatic individuals. Saliva, as either an oral cavity swab or passive drool, was collected in an RNA stabilization buffer. The stabilized saliva specimens were heat-treated and directly analyzed without RNA extraction. The diagnostic sensitivity of saliva-based RT-qPCR was at least 95% in individuals with subclinical infection and outperformed RT-LAMP, which had at least 70% sensitivity when compared to NSBs analyzed with a clinical RT-qPCR test. The diagnostic sensitivity for passive drool saliva was higher than that of oral cavity swab specimens (95% and 87%, respectively). A rapid, sensitive one-step extraction-free RT-qPCR test for detecting SARS-CoV-2 in passive drool saliva is operationally simple and can be easily implemented using existing testing sites, thus allowing high-throughput, rapid, and repeated testing of large populations. Furthermore, saliva testing is adequate to detect individuals in an asymptomatic screening program and can help improve voluntary screening compliance for those individuals averse to various forms of nasal collections.
Keywords: SARS-CoV-2, COVID-19, COVID-19 serological testing, real-time polymerase chain reaction, saliva, oral cavity swab, passive drool, pooling
Published in DiRROS: 09.11.2021; Views: 1168; Downloads: 563
URL Link to full text

38.
Stabilni izotopi v gozdnem ekosistemu - analizne metode in uporaba
Saša Zavadlav, Grega E. Voglar, Polona Hafner, Mitja Ferlan, Tom Levanič, 2016, published scientific conference contribution abstract

Keywords: stabilni izotopi, masna spektrometrija, laserska absorpcijska spektroskopija, EA-IRMS, OA-ICOS
Published in DiRROS: 03.11.2021; Views: 817; Downloads: 277
.pdf Full text (1,29 MB)

39.
Environmental signals in Quercus robur L. tree-ring widths and [delta]13C
Polona Hafner, Jožica Gričar, Mitja Skudnik, Tom Levanič, 2015, published scientific conference contribution abstract

Published in DiRROS: 03.11.2021; Views: 581; Downloads: 201
.pdf Full text (1,05 MB)

40.
Ocena poškodovanosti dreves z elektronsko paramagnetno resonanco Mn2+ ionov
Zorka Stolič, Franc Batič, Polona Kalan, Marjanca Nemec, Milan Valter Schara, 1998, original scientific article

Abstract: Ocena poškodovanosti dreves z elektronsko paramagnetno resonanco Mn2+ ionov
Keywords: elektronska paramagnetna resonanca, EPR Mn2+, smreka, iglica, poškodovanost drevesa, zdravstveno stanje
Published in DiRROS: 03.11.2021; Views: 918; Downloads: 271
.pdf Full text (565,85 KB)

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