Marijan Nečemer

Aluminosilicate materials, known for their high strength, corrosion resistance, and thermal stability, are synthesized through the alkali activation of metakaolin, incorporating Sm₂O₃ to investigate the impact on their physicochemical properties. This study takes a look at the synthesis and physicochemical characterization of aluminosilicate gels doped with samarium(III)-oxide (Sm₂O₃), focusing on their potential as thermal insulators due to their enhanced thermal conductivity and absorption properties. Two samples with 1% and 5% Sm₂O₃ by weight were investigated, referred to as S₁ and S₂, respectively. Characterization techniques such as energy-dispersive X-ray fluorescence spectrometry (EDXRF), diffuse reflectance infrared Fourier transform spectroscopy (DRIFT), scanning electron microscopy (SEM), and photothermal beam deflection (PBD) were employed for the physicochemical characterization of aluminosilicate materials. The structural analysis shows an integration of Sm₂O₃, which did not significantly affect the gel’s density or porosity but enhanced its thermal conductivity. This study shows the potential of Sm₂O₃-doped aluminosilicates in applications requiring improved thermal management and stability, positioning them as potentially suitable materials for insulation.

Podzemelj in Bela Krajina region have long been recognised as one of the key and best-researched Iron Age centres of the Dolenjska Hallstatt culture. The recently excavated large cemetery at Pezdirčeva njiva, situated on the north-western slope beneath the hillfort on Kučar, opens a new chapter in the study of this centre and the wider Dolenjska region. Burials at the site begin only in the 5th century BCE and continue uninterrupted until the early 1st century BCE. This monograph provides the first comprehensive publication of modern excavations of graves belonging to the Vinica cultural sphere, which until now had not been systematically analysed. The volume brings together the results of several years of fieldwork directed by Otmar Kovač and the author, and presents detailed documentation of more than 180 graves with rich assemblages of grave goods. The finds are illustrated on 85 plates, and a large-scale plan of the central part of the cemetery is included as an appendix. Analyses of funerary practices, costume, weaponry, pottery, and jewellery are complemented by a wide array of scientific studies assembled in Chapter 10. The monograph incorporates the results of pedological and geoarchaeological research (A. Prijatelj, H. Grčman, R. Turniški) and conservation–archaeometallurgical examinations of non-ceramic finds (N. Nemeček, M. Petrič, P. Fajfar, B. Šetina Batič, M. Nečemer). Additional contributions address textile remains (M. Gleba), archaeobotanical samples (T. Tolar), lithic finds (R. Brajkovič), and amber (M. Golec, Z. Golec Mírová, L. Kučera, J. Martínek). A particular strength of the monograph lies in its cultural and chronological synthesis, which situates Pezdirčeva njiva within the broader development of the Iron Age centre at Podzemelj and clarifies the structural and temporal differences between Late Hallstatt and Vinica-period graves. This comprehensive and interdisciplinary work significantly advances our understanding of settlement dynamics in Bela Krajina, from Podzemelj to Vinica, and provides new insights into cultural processes unfolding along the southeastern Alpine region during the Early and Late Iron Age.

Jeseni 2022 so iskalci arheoloških najdb z detektorji kovin v Stranicah pri Zrečah odkrili več bronastih predmetov. Našli naj bi jih na petih različnih mikrolokacijah na pobočju vzhodno in zahodno od kamnoloma. Dvesto šestdeset kosov in tri fotografije z bolje ohranjenimi predmeti so bili predani delavcem Koroškega pokrajinskega muzeja. Pregled artefaktov je pokazal, da gre za dele orožja, orodja, nakita, pločevine in ingotov, katerih časovni razpon sega od srednje in začetka mlajše bronaste dobe (Bd C/D) do konca žarnogrobiščnega obdobja oz. začetka starejše železne dobe. Večina predmetov ima primerjave v depojih druge stopnje kulture žarnih grobišč v Karpatski kotlini, na zahodnem delu Balkana, v vzhodnem Sredozemlju in Italiji. Kemijske analize, izvedene z metodo induktivno sklopljene plazme z masnim spektrometrom (ICP-MS), so pokazale na odstopanje v sestavi brona v primerjavi z obema okvirno sočasnima depojema v jugovzhodnih Alpah po višjem deležu niklja med nelegirnimi elementi.

This study attempts to clarify the effect of canopy position on the physico-chemical parameters of apples cv. Braeburn. The experiments were carried out on fruit from the inner and outer part of the canopy in two growing seasons and at two harvest dates. Light measurements revealed that the average value of photo active radiation (PAR) for the inside and outside canopy amounted to 30.3 μmol/m²/s and 133.7 μmol/m²/s, respectively. Production year and canopy position significantly influenced ground color parameters a*, b*, C*, and h°, while the harvest date influenced all color parameters studied. For additional (red blush) coloration, the production year significantly influenced only the L* parameter, harvest date influenced all color parameters, and canopy position influenced L, a*, and C*. Only the fruits of the second harvest date showed more intense additional (red blush) coloration. The production year significantly affected fruit mass, firmness, total soluble solids (SSC), titratable acidity (TA), SSC/TA ratio, DPPH radical scavenging assay (AOP), total phenolic content (TPC), and total flavonoid content (TFC). The harvest date significantly influenced fruit mass, SSC, TA, SSC/TA, AOP, TPC, and TFC. The canopy position significantly influenced SSC, TA, AOP, TPC, and TFC. Regarding mineral content, the production year significantly affected the content of Fe, Ni, Cu, and Ca and the K/Ca ratio. The harvest date significantly affected Fe, Cu, Sr, K and K/Ca. The canopy position affected Fe, Ni, Zn, Sr, Ca, and K/Ca ratio, with a clear significant trend regarding the effect of canopy position only for Ca content (first and second year of the second harvest date) and K/Ca ratio (first year of both harvest dates). PCA analyses identified distinguishing features between apples, with differences defined specifically by AOP, TPC, TFC, Rb, Sr, Ca, and K/Ca on the PC 1 and Mn, Fe, Ni, Cu, and Zn on PC 2.

While the demand for Spirulina dietary supplements continues to grow, product inspection in terms of authenticity and safety remains limited. This study used the stable isotope ratios of light elements (C, N, S, H, and O) and the elemental composition to characterize Spirulina dietary supplements available on the Slovenian market. Forty-six samples were labelled as originating from the EU (1), non-EU (6), Hawaii (2), Italy (2), Japan (1), Portugal (2), Taiwan (3), India (4), and China (16), and nine products were without a declared origin. Stable isotope ratio median values were –23.9‰ (–26.0 to –21.8‰) for δ¹³C, 4.80‰ (1.30–8.02‰) for δ¹⁵N, 11.0‰ (6.79–12.7‰) for δ³⁴S, –173‰ (– 190 to –158‰) for δ²H, and 17.2‰ (15.8–18.8‰) for δ¹⁸O. Multivariate statistical analyses achieved a reliable differentiation of Hawaiian, Italian, and Portuguese (100%) samples and a good separation of Chinese samples, while the separation of Indian and Taiwanese samples was less successful, but still notable. The study showed that differences in isotopic and elemental composition are indicative of sample origins, cultivation and processing methods, and environmental conditions such that, when combined, they provide a promising tool for determining the authenticity of Spirulina products.

The microalgae Spirulina may be a popular dietary supplement rich in essential nutrients and vitamins, but oversight of the supplement industry, in general, remains limited, and increasing incidents of adulteration, misbranding, and undeclared ingredients together with misleading claims create potential risks. In response, this study characterized the elemental, amino acid and fatty acid content of commercially available Spirulina supplements in Slovenia using EDXRF, ICP-MS and GC-MS and compared the results with their nutritional declaration. The gathered data confirm that Spirulina supplements are a good source of calcium (0.15 to 29.5% of RDA), phosphorous (3.36–26.7% of RDA), potassium (0.5 to 7.69% of RDA) and selenium (0.01 to 38.6% of RDA) when consumed within recommended amounts. However, although iron contents were relatively high (7.64 to 316% of RDA), the actual bioavailability of iron was much lower since it was mainly present as the ferric cation. This study also confirms that pure Spirulina supplements are a good source of essential and non-essential amino acids, and ω-6 but not ω-3 polyunsaturated fatty acids. The presence of additives resulted in significant variation in nutrient content and, in some instances, lower product quality. Moreover, a high proportion (86.7%) of inappropriate declarations regarding the elemental content was observed. Overall, the study conclusions underline the need for a stricter control system for Spirulina-based supplements.

We appreciate Dr Horacek’s interest in our paper and his feedback