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41.
Application of electrochemical methods for studying steel corrosion in alkali-activated materials
Shishir Mundra, Gabriel Samson, Giulia Masi, Rebecca Achenbach, David M. Bastidas, Susana Bernal, Maria Chiara Bignozzi, Maria Criado, Martin Cyr, Nina Gartner, Stefanie von Greve‐Dierfeld, Andraž Legat, Nikoonasab Ali, John L. Provis, Michael Raupach, Gregor J. G. Gluth, 2023, original scientific article

Abstract: Alkali‐activated materials (AAMs) are binders that can complement and partially substitute the current use of conventional cement. However, the present knowledge about how AAMs protect steel reinforcement in concrete elements is incomplete, and uncertainties exist regarding the application of electrochemical methods to investigate this issue. The present review by EFC WP11‐Task Force ‘Corrosion of steel in alkali‐activated materials’ demonstrates that important differences exist between AAMs and Portland cement, and between different classes of AAMs, which are mainly caused by differing pore solution compositions, and which affect the outcomes of electrochemical measurements. The high sulfide concentrations in blast furnace slag‐based AAMs lead to distinct anodic polarisation curves, unusually low open circuit potentials, and low polarisation resistances, which might be incorrectly interpreted as indicating active corrosion of steel reinforcement. No systematic study of the influence of the steel–concrete interface on the susceptibility of steel to corrosion in AAMs is available. Less common electrochemical methods present an opportunity for future progress in the field.
Keywords: alkali-aktivated materials, alkali‐activated materials, anodic/cathodic polarisation, concrete, linear polarisation resistance, open circuit potential, reinforcement corrosion, resistivity
Published in DiRROS: 29.05.2023; Views: 382; Downloads: 166
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42.
Mode I fracture of beech-adhesive bondline at three different temperatures
Jaka Gašper Pečnik, Andreja Pondelak, Michael David Burnard, Václav Sebera, 2022, original scientific article

Abstract: Single edge-notched three-point bending tests (SEN-TPB) for mode I were utilized to experimentallyevaluate fracture properties of adhesive bondlines in European beech (Fagus SylvaticaL.). Thebondline was examined at two anatomical planes with TR and RT orientation and at control andtwo elevated temperatures (70°C and 140°C). Among epoxy (EPI), melamine-urea formaldehyde (MUF), and polyurethane (PUR) adhesives, the highest average critical energyGcwith 0.80 N/mmand fracture energyGfwith 1079.4 N/mm were obtained for EPI in the TR plane and understandard climate conditions (20°C/65% relative humidity), followed by MUF (Gc= 0.50 N/mm andGf= 620 N/mm) and PUR (Gc= 0.25 N/mm andGf= 290.9 N/mm), respectively. PUR was leasteffected by elevated temperature, and no significant differences forGcandGfbetween TR and RTbondline orientations were found for MUF and PUR treated at 20°C/65% relative humidity whilecomparisons between other factors varied significantly. Treatment of specimens at elevatedtemperatures resulted in reduced fracture performance regardless of wood grain orientation orthe adhesive system.
Keywords: crack, fracture, grain orientation, temperature, European Beech, odprti dostop
Published in DiRROS: 03.05.2023; Views: 533; Downloads: 403
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43.
Multiscale femoral neck imaging and multimodal trabeculae quality characterization in an osteoporotic bone sample
Enrico Soldati, Flavy Roseren, Daphne Guenoun, Lucia Mancini, Emilio Catelli, Silvia Prati, Giorgia Sciutto, Jerome Vicente, Stefano Iotti, David Bendahan, Emil Malucelli, Martine Pithioux, 2022, original scientific article

Abstract: Although multiple structural, mechanical, and molecular factors are definitely involved in osteoporosis, the assessment of subregional bone mineral density remains the most commonly used diagnostic index. In this study, we characterized bone quality in the femoral neck of one osteoporotic patients as compared to an age-matched control subject, and so used a multiscale and multimodal approach including X-ray computed microtomography at different spatial resolutions (pixel size: 51.0, 4.95 and 0.9 µm), microindentation and Fourier transform infrared spectroscopy. Our results showed abnormalities in the osteocytes lacunae volume (358.08 ± 165.00 for the osteoporotic sample vs. 287.10 ± 160.00 for the control), whereas a statistical difference was found neither for shape nor for density. The osteoporotic femoral head and great trochanter reported reduced elastic modulus (Es) and hardness (H) compared to the control reference (−48% (p < 0.0001) and −34% (p < 0.0001), respectively for Es and H in the femoral head and −29% (p < 0.01) and −22% (p < 0.05), respectively for Es and H in the great trochanter), whereas the corresponding values in the femoral neck were in the same range. The spectral analysis could distinguish neither subregional differences in the osteoporotic sample nor between the osteoporotic and healthy samples. Although, infrared spectroscopic measurements were comparable among subregions, and so regardless of the bone osteoporotic status, the trabecular mechanical properties were comparable only in the femoral neck. These results illustrate that bone remodeling in osteoporosis is a non-uniform process with different rates in different bone anatomical regions, hence showing the interest of a clear analysis of the bone microarchitecture in the case of patients’ osteoporotic evaluation
Keywords: synchrotron X-ray microtomography, bone, trabecular struicture, osteons, osteoporosis, phase-contrast imaging, open access
Published in DiRROS: 28.04.2023; Views: 443; Downloads: 215
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44.
Soil contamination in nearby natural areas mirrors that in urban greenspaces worldwide
Yu-Rong Liu, Marcel G. A. van der Heijden, Judith Riedo, Carlos Sanz-Lazaro, David J. Eldridge, Felipe Bastida, Eduardo Moreno-Jiménez, Xin-Quan Zhou, Hang-Wei Hu, Ji-Zheng He, Tine Grebenc, Tina Unuk Nahberger, 2023, original scientific article

Abstract: Soil contamination is one of the main threats to ecosystem health and sustainability. Yet little is known about the extent to which soil contaminants differ between urban greenspaces and natural ecosystems. Here we show that urban greenspaces and adjacent natural areas (i.e., natural/semi-natural ecosystems) shared similar levels of multiple soil contaminants (metal(loid)s, pesticides, microplastics, and antibiotic resistance genes) across the globe. We reveal that human influence explained many forms of soil contamination worldwide. Socio-economic factors were integral to explaining the occurrence of soil contaminants worldwide. We further show that increased levels of multiple soil contaminants were linked with changes in microbial traits including genes associated with environmental stress resistance, nutrient cycling, and pathogenesis. Taken together, our work demonstrates that human-driven soil contamination in nearby natural areas mirrors that in urban greenspaces globally, and highlights that soil contaminants have the potential to cause dire consequences for ecosystem sustainability and human wellbeing.
Keywords: soil contamination, urban greenspaces
Published in DiRROS: 28.03.2023; Views: 707; Downloads: 299
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45.
Ascertaining the knowledge of the general public and stakeholders in the forestry sector to invasive alien species - a Pan-European study
Flavius Balacenoiu, Anže Japelj, Iris Bernardinelli, Bastien Castagneyrol, György Csóka, Milka Glavendekić, Gernot Hoch, Boris Hrašovec, Silvija Krajter Ostoić, Márton Paulin, David Williams, Johan Witters, Maarten De Groot, 2023, original scientific article

Abstract: Against the background of the phenomenon of globalisation, which has increasingly intensified in recent decades, invasive alien species (IAS) have led to biological invasions that have resulted in multiple negative effects on economies, human health, and especially on the environment. In order to control invasive alien species, preventive actions are considered the most effective methods. In this context, society can actively participate in the process of early detection and preventing the spread of these organisms, but there is a need to raise public awareness. In order for this process to take place in the most efficient way, it is necessary to initially evaluate the knowledge of the general public to IAS. Through a questionnaire that was circulated in ten European countries and had over two thousand respondents, this study aimed to investigate the level of knowledge of some stakeholders in the forestry sector regarding IAS. The results showed that a vast majority of respondents who participated in the study had heard about IAS and provided a correct definition of these organisms. Most of the respondents in this study heard for the first time about IAS from school, the Internet, or journal articles. Data analysis also showed that stakeholders in the forestry sector (foresters, forest owners, and members of environmental NGOs) were more likely than the other respondents to be aware of the impact of IAS. The results of this study offer an insight to researchers and decision makers assessing the differences of opinion regarding invasive alien species, and the necessary steps that could be adopted in the process of raising awareness in society.
Keywords: citizen science, online survey, biosecurity
Published in DiRROS: 09.03.2023; Views: 680; Downloads: 282
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46.
Teaching feints to handball beginners, preliminary results
David Henigman, Katarina Ohnjec, 2021, other scientific articles

Abstract: The aim of this preliminary research was the evaluation of a two-month program for improvement of the single forward feint to the left with passage to the right, and single forward feint to the right with passage to the left by “shifting” the opponent’s hand. Six-teen young male handball players aged 9.64 ± 0.87 years participated in this study. The program was implemented over two months, during which 18 training sessions (35%) were conducted for the improvement of feint skills, from 52 training sessions overall. An initial video recording was made at the beginning of the period, and a final one at the end. Videos were analyzed by three experts, using a grading list and detailed grad-ing criteria. The basic parameters of descriptive statistics were determined for both variables. The metric characteristics of the expert estimation contribution were ana-lyzed through measures of reliability (Cronbach’s α) and homogeneity (average item inter-correlation). The non-parametric (Wilcoxon t-test) method was used to analyze changes in the levels of feint performance at different times. The results indicate satis-factory reliability and homogeneity of the tests (α1=0.90; r1=0.80; α2 =0.86; r2=0.87). Through insight into the results, a significant difference was spotted between the initial and final states of both motor skills acquisitions (T1 = 114.5, p= 0.01; T2 =7.00; p= 0.01). The limiting factors of the study may be the sample size, as well as the absence of a control group and of a validated evaluation of the instrument
Keywords: handball, handball players, teaching methods, motor skills, work program, single feint
Published in DiRROS: 02.03.2023; Views: 431; Downloads: 194
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47.
First report of Erysiphe corylacearum on Corylus avellana and C. colurna in Slovenia
Janja Zajc, Mojca Rot, David Snoj, Metka Žerjav, Hans-Josef Schroers, Barbara Piškur, Nikica Ogris, Ana Brglez, 2023, other scientific articles

Keywords: common hazel, Turkish hazel, powdery mildew
Published in DiRROS: 28.02.2023; Views: 583; Downloads: 235
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48.
49.
CitieS-Health : Ljubliteljska znanost za zdravje v mestnem okolju
David Kocman, Uroš Kunaver, 2022, professional film, videorecordings or sound recordings

Keywords: občanska znanost, projekt Horizon 2020, okoljska znanost, Projekt Cities-Health, zdravje na delovnem mestu
Published in DiRROS: 31.01.2023; Views: 422; Downloads: 198
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50.
A glimpse of the lost Upper Triassic to Middle Jurassic architecture of the Dinaric Carbonate Platform margin and slope
Boštjan Rožič, Luka Gale, Primož Oprčkal, Astrid Švara, Tomislav Popit, Lara Kunst, Dragica Turnšek, Tea Kolar-Jurkovšek, Andrej Šmuc, Aljaž Iveković, Jan Udovč, David Gerčar, 2022, original scientific article

Abstract: In the southernmost outcrops of the Slovenian Basin the Middle Jurassic coarse-grained limestone breccia (mega)beds are interstratified within a succession that is otherwise dominated by hemipelagites and distal turbidites. In this paper, these beds are described as the Ponikve Breccia Member of the Tolmin Formation. We provide descriptions of the studied sections with detailed geological maps and analysis of the breccia lithoclasts. From the latter, a non-outcropping margin of the Dinaric Carbonate Platform is reconstructed. In the Late Triassic the platform margin was characterized by a Dachstein-type marginal reef. After the end-Triassic extinction event, the platform architecture remained, but the reefs were replaced by sand shoals characterized by ooids. In the late Early Jurassic and/or early Middle Jurassic a slope area might have been dissected by normal faults and a step-like paleotopography was formed. In the Bajocian, during a period of major regional geodynamic perturbations, extensional or transtensional tectonic activity intensified and triggered the large-scale collapses of the Dinaric Carbonate Platform margin producing the limestone breccias described herein. This may in turn have caused a backstepping of the platform margin, as is evident from the occurrence of Late Jurassic marginal reefs that are installed directly above the Upper Triassic and Lower Jurassic inner platform successions.
Keywords: Slovenian Basin, Dinaric Carbonate Platform, Middle Jurassic, limestone breccia, debris-flow, stratigraphy, Ponikve breccia
Published in DiRROS: 18.01.2023; Views: 610; Downloads: 437
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