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1.
Atmospheric black carbon in the metropolitan area of La Paz and El Alto, Bolivia: concentration levels and emission sources
Valeria Mardoñez-Balderrama, Griša Močnik, Marco Pandolfi, Robin L. Modini, Fernando Velarde, Laura Renzi, Angela Marinoni, Jean-Luc Jaffrezo, Isabel Moreno R., Diego Aliaga, 2024, original scientific article

Abstract: Abstract. Black carbon (BC) is a major component of submicron particulate matter (PM), with significant health and climate impacts. Many cities in emerging countries lack comprehensive knowledge about BC emissions and exposure levels. This study investigates BC concentration levels, identifies its emission sources, and characterizes the optical properties of BC at urban background sites of the two largest high-altitude Bolivian cities: La Paz (LP) (3600 m above sea level) and El Alto (EA) (4050 m a.s.l.), where atmospheric oxygen levels and intense radiation may affect BC production. The study relies on concurrent measurements of equivalent black carbon (eBC), elemental carbon (EC), and refractory black carbon (rBC) and their comparison with analogous data collected at the nearby Chacaltaya Global Atmosphere Watch Station (5240 m a.s.l). The performance of two independent source apportionment techniques was compared: a bilinear model and a least-squares multilinear regression (MLR). Maximum eBC concentrations were observed during the local dry season (LP: eBC = 1.5 ± 1.6 µg m−3; EA: 1.9±2.0 µg m−3). While eBC concentrations are lower at the mountain station, daily transport from urban areas is evident. Average mass absorption cross sections of 6.6–8.2 m2 g−1 were found in the urban area at 637 nm. Both source apportionment methods exhibited a reasonable level of agreement in the contribution of biomass burning (BB) to absorption. The MLR method allowed the estimation of the contribution and the source-specific optical properties for multiple sources, including open waste burning.
Keywords: black carbon, aerosol absorption, source apportionment, mass absorption cross-section
Published in RUNG: 29.10.2024; Views: 327; Downloads: 0
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2.
Negative pragmatic transfer in bilinguals : cross‑linguistic influence in the acquisition of quantifiers
Greta Mazzaggio, Penka Stateva, 2024, original scientific article

Abstract: Building on the cross-linguistic variability in the meaning of vague quantifiers, this study explores the potential for negative transfer in Italian-Slovenian bilinguals concerning the use of quantificational determiners, specifically the translational equivalents of the English “many”, that is the Slovenian "precej" and "veliko". The aim is to identify relevant aspects of pragmatic knowledge for cross-linguistic influence. The study presents the results of a sentence-picture verification task in which Slovenian native speakers and Italian-Slovenian bilinguals evaluated sentences of the form "Quantifier X are Y" in relation to visual contexts. The results suggest that Italian learners of Slovenian, unlike Slovenian native speakers, fail to distinguish between "precej" and "veliko". This finding aligns with the negative transfer hypothesis. The study highlights the potential role of pragmatic knowledge in cross-linguistic transfer, particularly in the context of vague quantifiers.
Keywords: quantification, cross-linguistic differences, pragmatics, semantics, negative transfer
Published in RUNG: 20.08.2024; Views: 800; Downloads: 6
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3.
Recommendations for reporting equivalent black carbon (eBC) mass concentrations based on long-term pan-European in-situ observations
Marjan Savadkoohi, Marco Pandolfi, Olivier Favez, Jean-Philippe Putaud, Konstantinos Eleftheriadis, Markus Fiebig, Philip Hopke, Paolo Laj, A. Wiedensohler, Griša Močnik, 2024, original scientific article

Abstract: A reliable determination of equivalent black carbon (eBC) mass concentrations derived from filter absorption photometers (FAPs) measurements depends on the appropriate quantification of the mass absorption cross-section (MAC) for converting the absorption coefficient (babs) to eBC. This study investigates the spatial–temporal variability of the MAC obtained from simultaneous elemental carbon (EC) and babs measurements performed at 22 sites. We compared different methodologies for retrieving eBC integrating different options for calculating MAC including: locally derived, median value calculated from 22 sites, and site-specific rolling regression MAC. The eBC concentrations that underwent correction using these methods were identified as LeBC (local MAC), MeBC (median MAC), and ReBC (Rolling MAC) respectively. Pronounced differences (up to more than 50 %) were observed between eBC as directly provided by FAPs (NeBC; Nominal instrumental MAC) and ReBC due to the differences observed between the experimental and nominal MAC values. The median MAC was 7.8 ± 3.4 m2/g from 12 aethalometers at 880 nm, and 10.6 ± 4.7 m2/g from 10 MAAPs at 637 nm. The experimental MAC showed significant site and seasonal dependencies, with heterogeneous patterns between summer and winter in different regions. In addition, long-term trend analysis revealed statistically significant (s.s.) decreasing trends in EC. Interestingly, we showed that the corresponding corrected eBC trends are not independent of the way eBC is calculated due to the variability of MAC. NeBC and EC decreasing trends were consistent at sites with no significant trend in experimental MAC. Conversely, where MAC showed s.s. trend, the NeBC and EC trends were not consistent while ReBC concentration followed the same pattern as EC. These results underscore the importance of accounting for MAC variations when deriving eBC measurements from FAPs and emphasizes the necessity of incorporating EC observations to constrain the uncertainty associated with eBC.
Keywords: equivalent black carbon, mass absorption cross-section, filter absorption photometers, elemental carbon, absorption, site specific MAC, rolling MAC
Published in RUNG: 04.03.2024; Views: 1439; Downloads: 10
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4.
Studies of the mass composition of cosmic rays and proton-proton interaction cross-sections at ultra-high energies with the Pierre Auger Observatory
Olena Tkachenko, Andrej Filipčič, Jon Paul Lundquist, Shima Ujjani Shivashankara, Samo Stanič, Serguei Vorobiov, Danilo Zavrtanik, Marko Zavrtanik, 2023, published scientific conference contribution

Abstract: In this work, we present an estimate of the cosmic-ray mass composition from the distributions of the depth of the shower maximum (�max) measured by the fluorescence detector of the Pierre Auger Observatory. We discuss the sensitivity of the mass composition measurements to the uncertainties in the properties of the hadronic interactions, particularly in the predictions of the particle interaction cross-sections. For this purpose, we adjust the fractions of cosmic-ray mass groups to fit the data with �max distributions from air shower simulations. We modify the proton-proton cross-sections at ultra-high energies, and the corresponding air shower simulations with rescaled nucleus-air cross-sections are obtained via Glauber theory. We compare the energydependent composition of ultra-high-energy cosmic rays obtained for the different extrapolations of the proton-proton cross-sections from low-energy accelerator data.
Keywords: Pierre Auger Observatory, ultra-high energy cosmic rays, extensive air shower, hadronic interactions, cross-section, Xmax
Published in RUNG: 23.01.2024; Views: 2081; Downloads: 6
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5.
Measurement of the Proton-Air Cross Section with Telescope Arrays Black Rock, Long Ridge, and Surface Array in Hybrid Mode.
R. Abbasi, Jon Paul Lundquist, 2022, published scientific conference contribution

Abstract: Ultra High Energy Cosmic Ray (UHECR) detectors have been reporting on the proton-air cross section measurement beyond the capability of particle accelerators since 1984. The knowledge of this fundamental particle property is vital for our understanding of high energy particle interactions and could possibly hold the key to new physics. The data used in this work was collected over eight years using the hybrid events of Black Rock (BR) and Long Ridge (LR) fluorescence detectors as well as the Telescope Array Surface Detector (TASD). The proton-air cross section is determined at s√=73~TeV by fitting the exponential tail of the Xmax distribution of these events. The proton-air cross section is then inferred from the exponential tail fit and from the most updated high energy interaction models. σ^inel_p−air is observed to be 520.1±35.8 [Stat.] +25.3−42.9 [Sys.] mb. This is the second proton-air cross section work reported by the Telescope Array collaboration.
Keywords: Telescope Array, indirect detection, hybrid detection, ground array, fluorescence detection, ultra-high energy, cosmic rays, Xmax, proton-air cross-section, high energy particle interaction
Published in RUNG: 04.10.2023; Views: 1660; Downloads: 5
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6.
The ultra-high-energy cosmic-ray sky above 32 EeV viewed from the Pierre Auger Observatory
J. Biteau, Andrej Filipčič, Jon Paul Lundquist, Samo Stanič, Serguei Vorobiov, Danilo Zavrtanik, Marko Zavrtanik, Lukas Zehrer, 2022, published scientific conference contribution

Abstract: The region of the toe in the cosmic-ray spectrum, located at about 45 EeV by the Pierre Auger Collaboration, is of primary interest in the search for the origin of ultra-high energy cosmic rays (UHECRs). The suppression of the flux with increasing energy can be explained by the interaction of UHECRs with intergalactic photons, resulting in a shrinking of the observable universe, and/or by cut-offs in acceleration potential at the astrophysical sources, yielding a high-rigidity sample of single (or few) UHECR species around the toe. The predominance of foreground sources combined with reduced deflections could thus offer a path towards localizing ultra-high energy accelerators, through the study of UHECR arrival directions. In this contribution, we present the results of blind and astrophysically-motivated searches for anisotropies with data collected above 32 EeV during the first phase of the Pierre Auger Observatory, i.e. prior to the AugerPrime upgrade, for an exposure of over 120,000 km^2 yr sr. We have conducted model-independent searches for overdensities at small and intermediate angular scales, correlation studies with several astrophysical structures, and cross-correlation analyses with catalogs of candidate extragalactic sources. These analyses provide the most important evidence to date for anisotropy in UHECR arrival directions around the toe as measured from a single observatory.
Keywords: Pierre Auger Observatory, indirect detection, surface detection, ground array, ultra-high energy, cosmic rays, anisotropy, overdensities, hotspot, source correlation, cross-correlation
Published in RUNG: 04.10.2023; Views: 1504; Downloads: 7
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7.
Two ʺmanyʺ- words in Italian? : on molto-tanto and cross-linguistic differences in quantification
Greta Mazzaggio, Penka Stateva, 2023, original scientific article

Abstract: This article investigates the variability in the meaning of vague quantifiers across different languages, focusing on Italian’s m(any)-words molto and tanto. The aim was to replicate a previous analysis conducted on Slovenian m-words – precej and veliko – examining whether the Italian ones exhibit a similar pragmatic strengthening effect. Using a sentence-picture verification task, we tested 88 Italian monolingual participants on their evaluation of sentences of the form “Quantifier X are Y”. Our results showed that, unlike Slovenian speakers, Italian speakers do not exhibit a difference in the evaluation of molto and tanto, suggesting that the two words have the same numerical bound and are interchangeable as amount modifiers. Our analysis suggests that there are underlying semantic distinctions between molto and tanto that require further investigation. These findings contribute to our understanding of the variability in the use of quantifiers across languages and highlight the importance of examining subtle differences in meaning when studying vague quantifiers.
Keywords: cross-linguistic differences, pragmatics, quantification, semantics, vague quantifiers
Published in RUNG: 03.10.2023; Views: 1921; Downloads: 10
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8.
Crossing Art, Science and Technology for Innovations through Maker Culture and Education
Kristina Pranjić, Peter Purg, Jernej Čuček Gerbec, 2022, published scientific conference contribution

Keywords: Cross-innovation, art thinking, making, interdisciplinary, embodiment, art practice, crafting, innovation, art-sci-tech
Published in RUNG: 06.03.2023; Views: 2019; Downloads: 0
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9.
Speckle interferometric investigation of argon pressure-induced surface roughness modifications in RF-sputtered MoO[sub]3 film
S. Soumya, R. Arun Kumar, S. Sreejyothi, Vimal Raj, Mohanachandran Nair Sindhu Swapna, Sankaranarayana Iyer Sankararaman, 2021, original scientific article

Abstract: Film quality analysis is of more considerable signifcance due to its diversifed applications in various felds of technology. The present work reports the speckle interferometric analysis of the argon pressure-induced surface roughness modifcations of RF sputtered MoO3 flms. The paper suggests a new method of surface quality analysis of thin flms through a parameter δ, which is the diference between the initial and fnal inertia moment values in the study of the thermal-induced dynamic speckle pattern. The limitations of root mean square surface roughness analysis of the atomic force microscopic image of the flms is also exemplifed. The research suggests that argon pressure plays a vital role in the surface property of RF sputtered flms and also that the dynamic speckle analysis can give precise information about the quality of flms. The contour plot of particle displacement vector under thermal stress, suggests the degree of uniformity in the distribution of particles in the flm.
Keywords: speckle pattern interferometry, time history of speckle pattern, cross correlation, inertia moment
Published in RUNG: 04.07.2022; Views: 1954; Downloads: 0
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10.
Fractal and inertia moment analyses for thin film quality monitoring
Mohanachandran Nair Sindhu Swapna, 2022, original scientific article

Abstract: The widespread applications of thin films in optronics demand innovative techniques for its characterizations. The work reported here proposes electronic speckle pattern interferometry and fractal-based methods for assessing the quality of thin films taking the industrially relevant molybdenum oxide (MoO3) incorporated niobium oxide (Nb2O5) films. The films with different levels of MoO3 incorporation (1, 2, 3, 5, and 10 wt. %) are prepared by radio frequency sputtering. The study reveals the structure modifications of Nb2O5 from the orthorhombic to monoclinic phases with an associated morphological variation revealed through atomic force microscopy and field-emission scanning electron microscopy analyses. The films’ specklegrams are recorded under thermal stress; the inertia moment (IM) and fractal analyses are computed and compared with the root-mean-square surface roughness of the films. The lacunarity analysis of the AFM films agrees well with the specklegrams. Thus, the lower IM and lacunarity values of the specklegrams can be regarded as indicators of the good quality of thin films.
Keywords: cross-correlation, fractal dimension, inertia moment, lacunarity, speckle, surface roughness.
Published in RUNG: 30.06.2022; Views: 2081; Downloads: 0
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