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21.
22.
O domorodnosti alpskega kozoroga v Sloveniji
Andreja Nève Repe, Elena Bužan, Borut Toškan, Jernej Javornik, Boštjan Pokorny, Andrej Arih, Lars Zver, Maruša Prostor, Miha Krofel, Matija Stergar, Klemen Jerina, Hubert Potočnik, Rok Černe, Aleš Poljanec, 2023, strokovni članek

Povzetek: Alpski kozorog (Capra ibex) je alpski endemit. Na območju Slovenije naj bi bila vrsta iztrebljena v drugi polovici 17. stoletja, globalno pa je bila zaradi prelova na robu izumrtja konec 19. stoletja. Preživela je le populacija na širšem območju parka Gran Paradiso na skrajnem zahodu Alp v Italiji. Zaradi naselitev in drugih varstvenih programov sedaj alpski kozorog živi v celotnih Alpah, vključno s Slovenijo. Vendar pri nas njegove populacije nazadujejo in so v zelo slabem stanju, kar je lahko rezultat več dejavnikov. Malo izvornih osebkov ob naselitvah, zgodovinska ozka grla in ločenost kolonij so povzročili parjenje v sorodstvu, kar je slabšalo genetsko stanje populacij in lahko negativno vpliva tudi na demografijo. K številčnemu zmanjševanju vrste so lahko prispevale tudi bolezni. Za dolgoročno ohranitev alpskega kozoroga v Sloveniji so nujni takojšnji aktivni ohranitveni ukrepi, pogoj pa je ustrezna opredelitev izvornosti vrste, saj je (bila) zaradi prejšnjih pomanjkljivih podatkov umeščena med tujerodne. V prispevku na podlagi arheo-zooloških, genetskih in preliminarnih habitatnih analiz utemeljujemo, da je v Sloveniji kozorog domorodna vrsta. V raziskavah smo pokazali, da je vrsta živela na ozemlju zdajšnje Slovenije v poznoantičnem in zgodnje srednjeveškem obdobju. Preliminarno smo določili tudi primernost in povezanost habitata kozoroga v slovenskem alpskem svetu ter nakazali verjetne potrebne ukrepe za ohranitev vrste v Sloveniji.
Ključne besede: Capra ibex, izvornost vrste, programi varstva, Alpe, habitat, genetika
Objavljeno v DiRROS: 09.01.2024; Ogledov: 235; Prenosov: 66
.pdf Celotno besedilo (475,48 KB)

23.
Low but significant evolutionary potential for growth, phenology and reproduction traits in European beech
Marjana Westergren, Juliette Archambeau, Marko Bajc, Rok Damjanić, Adélaïde Theraroz, Hojka Kraigher, Sylvie Oddou-Muratorio, Santiago C. González-Martínez, 2023, izvirni znanstveni članek

Povzetek: Local survival of forest tree populations under climate change depends on existing genetic variation and their adaptability to changing environments. Responses to selection were studied in European beech (Fagus sylvatica) under field conditions. A total of 1087 adult trees, seeds, 1-year-old seedlings and established multiyear saplings were genotyped with 16 nuSSRs. Adult trees were assessed for phenotypic traits related to growth, phenology and reproduction. Parentage and paternity analyses were used to estimate effective female and male fecundity as a proxy of fitness and showed that few parents contributed to successful regeneration. Selection gradients were estimated from the relationship between traits and fecundity, while heritability and evolvability were estimated using mixed models and the breeder's equation. Larger trees bearing more fruit and early male flowering had higher total fecundity, while trees with longer growth season had lower total fecundity (directional selection). Stabilizing selection on spring phenology was found for female fecundity, highlighting the role of late frosts as a selection driver. Selection gradients for other traits varied between measurement years and the offspring cohort used to estimate parental fecundity. Compared to other studies in natural populations, we found low to moderate heritability and evolvability for most traits. Response to selection was higher for growth than for budburst, leaf senescence or reproduction traits, reflecting more consistent selection gradients across years and sex functions, and higher phenotypic variability in the population. Our study provides empirical evidence suggesting that populations of long-lived organisms such as forest trees can adapt locally, even at short-time scales.
Ključne besede: climate change, Fagus sylvatica, heritability, in situ adaptation, response to selection, selection gradients
Objavljeno v DiRROS: 12.12.2023; Ogledov: 195; Prenosov: 93
.pdf Celotno besedilo (6,82 MB)
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24.
Evolution of surface functional groups and aromatic ring degradation upon treatment of polystyrene with hydroxyl radicals
Alenka Vesel, Rok Zaplotnik, Gregor Primc, Miran Mozetič, 2023, izvirni znanstveni članek

Povzetek: The surface properties of hydrocarbon polymers are inadequate for numerous applications. Hence, they require alteration via functionalisation with desired functional groups. Hydroxyl groups are often preferred, since they enable appropriate polarity for the irreversible grafting of desired molecules. In this study, the surface kinetics resulting from the treatment of polystyrene with hydroxyl (OH) radicals from the gas phase was fundamentally investigated through a precisely-designed experiment. Polystyrene samples were exposed to various known fluences of OH radicals, and the evolution of surface functional groups versus the OH fluence was monitored using high-resolution X-ray photoelectron spectroscopy (XPS). The fluences of OH radicals varied between 1 × 1018 and 4 × 1023 m−2 in the process of finding a threshold fluence for the formation of specific groups. The surface concentration of carbonyl (C=O) groups could be measured using XPS at a fluence of approximately 5 × 1020 m−2. The C=O groups became measurable at a fluence of approximately 1.5 × 1021 m−2, and carboxyl (COOH)/ester groups at approximately 4 × 1021 m−2. As deduced from the XPS, a concentration of C=O groups at approximately 5 % occurred before the degradation of the aromatic ring. The formation of other oxygen-functional groups required opening of the aromatic ring. The results have been explained using a two-step process, considering available theories vis-a-vis initial stages in the functionalisation of PS with polar functional groups.
Ključne besede: polistiren, kinetika površinske funkcionalizacije, OH radikali, vpliv doze radikalov, časovni razvoj, polystyrene, surface functionalisation kinetics, OH radicals
Objavljeno v DiRROS: 09.11.2023; Ogledov: 254; Prenosov: 110
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25.
Models for forecasting the traffic flow within the city of Ljubljana
Gašper Petelin, Rok Hribar, Gregor Papa, 2023, izvirni znanstveni članek

Povzetek: Efficient traffic management is essential in modern urban areas. The development of intelligent traffic flow prediction systems can help to reduce travel times and maximize road capacity utilization. However, accurately modeling complex spatiotemporal dependencies can be a difficult task, especially when real-time data collection is not possible. This study aims to tackle this challenge by proposing a solution that incorporates extensive feature engineering to combine historical traffic patterns with covariates such as weather data and public holidays. The proposed approach is assessed using a new real-world data set of traffic patterns collected in Ljubljana, Slovenia. The constructed models are evaluated for their accuracy and hyperparameter sensitivity, providing insights into their performance. By providing practical solutions for real-world scenarios, the proposed approach offers an effective means to improve traffic flow prediction without relying on real-time data.
Ključne besede: traffic modeling, time-series forecasting, traffic-count data set, machine learning, model comparison
Objavljeno v DiRROS: 28.09.2023; Ogledov: 320; Prenosov: 134
.pdf Celotno besedilo (5,05 MB)
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26.
27.
Recombination of oxygen atoms on the surface of oxidized polycrystalline nickel—temperature and pressure dependences
Domen Paul, Miran Mozetič, Rok Zaplotnik, Jernej Ekar, Alenka Vesel, Gregor Primc, Denis Đonlagić, 2023, izvirni znanstveni članek

Povzetek: The recombination of neutral oxygen atoms in the ground state on the oxidized nickel samples was studied experimentally in the range of pressures where the maximum density occurs in weakly ionized low-pressure oxygen plasma, i.e. between 40 and 200 Pa. The recombination coefficient was determined in the flowing afterglow. The source of oxygen atoms was plasma sustained in a quartz tube of inner diameter 4.7 mm by a microwave discharge in the surfatron mode. The recombination coefficient was determined in the afterglow chamber, which was a Pyrex tube with an inner diameter of 36 mm. The density of oxygen atoms in the afterglow chamber was varied by adjusting the discharge power, the gas flow, the pressure, and the position of a recombinator. Such flexibility of the experimental system enabled adjustment of the temperature of the oxidized nickel samples independently from the O-atom density in its vicinity or other parameters. The density of oxygen atoms in the afterglow chamber at various system parameters was determined by the Šorli method, which is reliable, and has an accuracy of about 20%. The recombination coefficient was determined by calorimetry. The coefficient was inversely proportional to the square root of the pressure and exponentially to the sample temperature. Systematic measurements performed at various pressures and temperatures enabled empirical formula, which were explained qualitatively by recombination kinetics.
Ključne besede: heterogenous surface recombination, recombination coefficient, nickel, nickel oxide, temperature
Objavljeno v DiRROS: 30.08.2023; Ogledov: 324; Prenosov: 190
.pdf Celotno besedilo (2,44 MB)
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28.
Loss of oxygen atoms on well-oxidized cobalt by heterogeneous surface recombination
Domen Paul, Miran Mozetič, Rok Zaplotnik, Jernej Ekar, Alenka Vesel, Gregor Primc, Denis Đonlagić, 2023, izvirni znanstveni članek

Povzetek: Calorimetry is a commonly used method in plasma characterization, but the accuracy of the method is tied to the accuracy of the recombination coefficient, which in turn depends on a number of surface effects. Surface effects also govern the kinetics in advanced methods such as atomic layer oxidation of inorganic materials and functionalization of organic materials. The flux of the reactive oxygen atoms for the controlled oxidation of such materials depends on the recombination coefficient of materials placed into the reaction chamber, which in turn depends on the surface morphology, temperature, and pressure in the processing chamber. The recombination coefficient of a well-oxidized cobalt surface was studied systematically in a range of temperatures from 300 to 800 K and pressures from 40 to 200 Pa. The coefficient increased monotonously with decreasing pressure and increasing temperature. The lowest value was about 0.05, and the highest was about 0.30. These values were measured for cobalt foils previously oxidized with oxygen plasma at the temperature of 1300 K. The oxidation caused a rich morphology with an average roughness as deduced from atomic force images of 0.9 µm. The results were compared with literature data, and the discrepancy between results reported by different authors was explained by taking into account the peculiarities of their experimental conditions.
Objavljeno v DiRROS: 25.08.2023; Ogledov: 311; Prenosov: 150
.pdf Celotno besedilo (3,59 MB)
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29.
Priporočila za obravnavo bolnikov s pljučnim rakom
Martina Vrankar, Nina Boc, Izidor Kern, Aleš Rozman, Karmen Stanič, Tomaž Štupnik, Mojca Unk, Maja Ebert Moltara, Vesna Zadnik, Katja Adamič, Jernej Benedik, Marko Bitenc, Jasna But-Hadžić, Anton Crnjac, Marina Čakš, Dominik Časar, Eva Ćirić, Tanja Čufer, Ana Demšar, Rok Devjak, Goran Gačevski, Marta Globočnik Kukovica, Kristina Gornik-Kramberger, Maja Ivanetič Pantar, Marija Ivanović, Urška Janžič, Staša Jelerčič, Veronika Kloboves-Prevodnik, Mile Kovačević, Luka Ležaič, Mateja Marc-Malovrh, Katja Mohorčič, Loredana Mrak, Igor Požek, Nina Turnšek, Bogdan Vidmar, Dušanka Vidovič, Gregor Vlačić, Ana Lina Vodušek, Rok Zbačnik, Ivana Žagar, 2023, strokovni članek

Povzetek: Leta 2019 so bila objavljena Priporočila za obravnavo bolnikov s pljučnim rakom, ki so v slovenski prostor vnesla prepotrebno poenotenje diagnostike in zdravljenja z namenom izboljšanja preživetja bolnikov s pljučnim rakom. Posodobitev Priporočil tri leta po izidu izvirnika prinaša največ novosti v poglavju o sistemskem zdravljenju bolnikov s pljučnim rakom. To kaže na izjemen napredek na področju razumevanja onkogeneze in biologije pljučnega raka ter s tem razvoja novih zdravil. Breme pljučnega raka ostaja veliko, saj je pljučni rak pri nas in v svetu še vedno najpogostejši vzrok smrti zaradi raka. Za vsako peto smrt zaradi raka je odgovoren pljučni rak. Skoraj tretjina bolnikov s pljučnim rakom ne prejme specifičnega onkološkega zdravljenja, bodisi zaradi slabega stanja zmogljivosti, spremljajočih bolezni ali obsega bolezni. Polovica bolnikov ima ob diagnozi razsejano bolezen, zaradi česar izboljšanje preživetja z malimi koraki sledi napredku v zdravljenju bolnikov s pljučnim rakom. Ti podatki nas opominjajo, da se bomo morali za velike premike v obravnavi bolnikov s pljučnim rakom lotiti drugačnih pristopov. Kot najbolj obetavno se ponuja zgodnje odkrivanje bolezni, ko so možnosti ozdravitve pljučnega raka najboljše. Zapisana Priporočila so usmeritev za obravnavo bolnikov s pljučnim rakom. Le s sodobnim multidisciplinarnim pristopom obravnave lahko bolniku ponudimo zdravljenje, ki mu omogoča najboljši izhod prognostično neugodne bolezni.
Ključne besede: pljučni rak, priporočila
Objavljeno v DiRROS: 27.07.2023; Ogledov: 380; Prenosov: 136
.pdf Celotno besedilo (708,18 KB)
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30.
Digital twins and road construction using secondary raw materials
Sebastjan Meža, Alenka Mauko Pranjić, Rok Vezočnik, Igor Osmokrović, Stanislav Lenart, 2021, izvirni znanstveni članek

Povzetek: Secondary raw materials (SRMs) tend to be a valuable replacement for finite virgin materials especially since construction works (i.e., building and civil engineering work such as road construction) require vast quantities of raw materials. Using SRM originating from recycling a broad range of inorganic waste materials (e.g., mining waste, different industrial wastes, construction, and demolition waste) has been recognized as a promising, generally more cost-efficient, and environmentally friendly alternative to the exploitation of natural resources. Despite the benefits of using SRM, several challenges need to be addressed before using SRM even more. One of them is the long-term durability and little-known response of construction works built using such alternative materials. In this paper, we present the activities to establish a fully functioning digital twin (DT) of a road constructed using SRM. The first part of the paper is devoted to the theoretical justification of efforts and ways of establishing the monitoring systems, followed by a DT case study where an integrated data environment synthesizing a Building Information Model and monitored data is presented. Although the paper builds upon a small scale, the case study is methodologically designed to allow parallels to be drawn with much larger construction projects.
Ključne besede: digital twins, road construction, circular economy
Objavljeno v DiRROS: 19.07.2023; Ogledov: 279; Prenosov: 189
.pdf Celotno besedilo (4,36 MB)
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