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Synthesis and characterization of catalytically active Ni(II) complexes with bis(phenol)diamine ligands
No full textA novel N,N’-dimethylethylenediamine derivative of substituted bis(phenol)diamine ligands, namely 2-(tert-butyl)-4-methylphenol in HL, was synthesized by a convenient green procedure. Nickel)II) complex [NiL] 1 has been synthesized and characterized by various methods along with crystal structure determined. Ni(II) coordination center in a mononuclear complex is surrounded by two phenolate oxygen atoms and two amine nitrogen atoms of the ligand in a square planar arrangement. The magnetic susceptibility of the title complex indicates a paramagnetic behavior above 150 K, while strong ferromagnetism below 100 K. Furthermore, the cyclic voltammetry studies show two ligand-centered oxidation of the phenolate groups to phenoxyl radical and the metal-centered reduction of Ni(II) to Ni(0). The Glaser coupling reaction of phenylacetylene was also studied. A strong catalytic activity at room T in THF solvent is observed for 1 in the presence of zinc powder as a reducing agent. A full conversion rate was achieved after 7 h at 25 °C. The DFT analysis corroborates with the square-planar NiON chromophore of 1 being reduced in catalytically active Ni(0) by applied Zn. The calculated Gibbs free energy of the reaction leading to the formation of the substrate Ni-complex is favorable endothermic. Most of the data for 1 were obtained also for the very similar previously reported [NiL] 2, with 2,4- di tert-butylphenol in HL, which were than compared
Biologija ježerilca Acanthocephalus anguillae v podzemnih habitatih
No full textThe trophically transmitted acanthocephalan Acanthocephalus anguillae typically cycles between waterlice (Asellus aquaticus) and freshwater fishes. Its presence in the Postojna–Planina Cave System (PPCS), where it infests cave-dwelling waterlice and the olm (Proteus anguinus), provides an exceptional opportunity to explore the ecological flexibility of this parasite while simultaneously raising important conservation considerations. This thesis applied an integrative approach combining parasitological examination of olm collection specimens, assessment of parasite gravidity, molecular analyses, behavioural experiments, and histological examinations. Systematic examination of olms collected between 1968 and 2022 revealed A. anguillae only in PPCS, with records beginning in 1994. The survey also provided the first confirmation of Pomphorhynchus sp. in olms, which predominated prior to the emergence of A. anguillae. Gravidity assessment revealed contrasting evidence of host suitability: while many parasites were extraintestinal and degraded, gravid females were found in recent specimens, indicating that the olm is a partially compatible host capable of supporting parasite reproduction. Genetic analyses showed substantial gene flow between cave and nearby surface populations of A. anguillae, supporting ongoing connectivity rather than long-term isolation. Behavioural experiments detected no novel manipulation of waterlice by A. anguillae adapted to subterranean conditions, as the reduction in photophobia persisted. Histological analyses revealed typical acanthocephalan-induced intestinal lesions in olms, although their impact on host health remains uncertain. Overall, A. anguillae represents a new population in PPCS sustained by surface influx. It appears to have recently gained the ability to reproduce in a cave definitive host, while its manipulation strategies in the intermediate host remain unadapted to subterranean conditions. Severe inflammatory responses and potential sublethal effects highlight the need for continued health monitoring of olm populations and their parasites.Ježerilec vrste Acanthocephalus anguillae običajno kroži med vodnimi oslički (Asellus aquaticus) in sladkovodnimi ribami. Njegova prisotnost v Postojnsko-planinskem jamskem sistemu (PPJS), kjer parazitira jamsko populacijo vodnih osličkov in močerila (Proteus anguinus), predstavlja edinstveno priložnost za preučevanje ekološke prilagodljivosti parazita in odpira pomembna naravovarstvena vprašanja. V doktorski nalogi je bil uporabljen celovit pristop, ki je združeval parazitološki pregled arhivske zbirke močerilov, oceno gravidnosti parazitov, molekularne analize parazita, vedenjske eksperimente in histopatološko analizo črevesa. Sistematični pregled močerilov zbranih med letoma 1968 in 2022, je prisotnost A. anguillae potrdil le v PPJS s prvimi zaznanimi pojavnostmi iz leta 1994. Pred tem je prevladovala okužba z ježerilcem iz rodu Pomphorhynchus, katerega prisotnost je bila v tej nalogi prvič potrjena. Ocena gravidnosti je potrdila prisotnost gravidnih samic A. anguillae v močerilih, kar kljub degradiranim primerkom izven črevesja kaže na primernost močerila kot končnega gostitelja. Genetske analize so pokazale znaten genetski pretok med jamsko in okoliškimi površinskimi populacijami A. anguillae, kar potrjuje povezanost in izključuje dolgotrajno izolacijo v podzemlju. Vedenjski poskusi niso pokazali novih ali okoljsko prilagojenih strategij manipulacije vmesnega gostitelja. Zmanjšanje fotofobije, kot ključne strategije manipulacije v površinskih vodah, se je namreč ohranilo tudi v jamskem okolju. Histopatološke spremembe črevesnega tkiva močerilov s pritjenimi paraziti so pokazale tipične lezije značilne za okužbe z ježerilci, medtem ko njihov vpliv na splošno stanje gostitelja ostaja negotov. A. anguillae predstavlja novo populacijo v PPJS, ki jo vzdržuje dotok jajčec s površja. Rezultati doktorske naloge kažejo, da je vrsta pridobila sposobnost spolnega razmnoževanja v jamskem gostitelju šele nedavno, medtem ko njene manipulacijske strategije v vmesnem gostitelju ostajajo neprilagojene podzemnemu okolju. Izrazit vnetni odziv in možni subletalni učinki poudarjajo potrebo po nadaljnjem spremljanju stanja populacij močerilov in njihovih parazitov
Characterization of sputtered thin films ITO for automotive applications
No full textV podjetju Hella Saturnus Slovenija d.o.o. proizvajajo izdelke za avtomobilsko industrijo, ki pogosto vsebujejo uporovne grelne elemente zabrizgane v polimere.
Uporovni grelci lahko delujejo tudi na osnovi (transparentnih) prevodnih tankih plasti.
V industriji najpogosteje uporabljen material za transparentne prevodne tanke plasti je In2O3–SnO2, indij kositrov oksid (ang. Indium Tin Oxide – ITO).
Cilj tega dela je bil ovrednotiti optične in električne lastnosti tankih plasti ITO, ki bi lahko potencialno nadomestile grelne elemente iz žic.
Z naprševanjem tankih plasti ITO smo izdelali šest šarž vzorcev, od katerih so bile štiri transparentne. Pri tem smo uporabili tri različne tarče – dve kovinski in eno oksidno.
Naprševali smo na podlage iz polikarbonata, stekla in silicija. Transparentnim šaržam smo izmerili debelino tanke plasti ITO po metodi profilometrije, transparentnost v
vidnem spektru po metodi UV-VIS spektroskopije, plastno električno upornost s štiritočkovno metodo in radarske lastnosti z metodama RMS (ang. Radome Measuring
System) ter QAR (ang. Quality Automotive Radome). Z uporabo vrstičnega elektronskega mikroskopa (SEM) smo analizirali mikrostrukturo tankih plasti ITO ter kemijsko sestavo z metodo energijske disperzijske spektroskopije (EDS).
Iz rezultatov, pridobljenih z meritvami in analizami, smo ugotovili, da večja debelina tanke plasti ITO prinese manjšo transparentnost v vidnem spektru in manjšo plastno
električno upornost. V odvisnosti od debeline tanke plasti se spreminja tudi kemijska sestava tanke plasti ITO.The company Hella Saturnus Slovenija d.o.o. manufactures products for the automotive industry that often incorporate resistive heating elements embedded in polymers. Resistive heaters can also be based on (transparent) conductive thin films.
The most used material in industry for transparent conductive thin films is In2O3–SnO2,
indium tin oxide (ITO).
The aim of this work was to evaluate the optical and electrical properties of ITO thin
films that could potentially replace wire-based heating elements. Using sputtering deposition, we prepared six batches of ITO thin film samples, four among them were transparent. We used three different targets – two metal and one oxide. We deposited the films onto polycarbonate, glass, and silicon substrates. For the transparent batches, the ITO film thickness was measured using profilometry, optical transmittance in the visible spectrum by UV–VIS spectroscopy, and layer resistance using the four-point probe method. Radar performance was evaluated using
the RMS (Radome Measuring System) and QAR (Quality Automotive Radome) methods. The microstructure of the ITO thin films was analysed using scanning
electron microscopy (SEM), while their chemical composition was determined by energy-dispersive spectroscopy (EDS).
From the results obtained by measurements and analyses, we concluded that an increase in ITO film thickness leads to a reduced optical transmittance in the visible spectrum and a lower layer electrical resistance. The chemical composition of ITO thin films also changes with film thickness
Fenotypic characterization of black yeast-like fungi isolated from the surface of photovoltaic panels
No full textFotovoltaični paneli so izpostavljeni ekstremnim okoljskim dejavnikom (UV, suša, temperaturna nihanja), kar otežuje vendar ne prepreči rasti mikroorganizmov (gliv, kvasovk, bakterij in arhej) in nastanek biofilmov. Ta biološka obrast skupaj z odlaganjem površinskih delcev zmanjšuje učinkovitost panelov, saj ovira dostop svetlobe do fotovoltaičnih celic. V nalogi smo preučili 28 izolatov, osamljenih s površin fotovoltaičnih panelov. Gojili smo jih na različnih gojiščih (MEA, OA, PDA, PNA in DG-18) in pri različnih temperaturah (4 ‒ 40 °C). S poravnano nukletotidnih zaporedij regije ITS s programom MEGA7, izrisom filogenetskega drevesa in uporabe programa BLAST ter fenotipskih lastnosti smo izolate uvrstili v deblo Ascomycota, v razrede Arthoniomycetes, Eurotiomycetes in Dothiodeomycetes, v rodove Phaeococcomyces, Neophaeococcomyces, Knufia, Trichomerium, Coniosporium, Dothiora, Constantinomyces, Neocatenulostroma, Capnobotryella, Elasticomyces, Neocatenulostroma, Neospissiomyces, med njimi je enajst še nepoimenovanih vrst. Sorodnost med izolati smo ugotavljali tudi z metodo MALDI-TOF MS. Na podlagi mikroskopskih značilnosti smo ugotovili, da so ključne lastnosti preučevanih taksonov, ki vplivajo na razrast in preživetje ekstremnega okolja fotovoltaičnih panelov, melanizacija (ščiti pred UV-sevanjem, deluje kot antioksidant in sodeluje pri termoregulaciji), meristematska/mikrokolonijska rast (boljša temperaturna toleranca, zmanjšano izsuševanje), ovoji iz EPS (olajšana adhezija, zaščitna mreža, ki omogoča preživetje ob temperaturnih in vodnih nihanjih), specifične reproduktivne strukture (endokonidiji in artrokonidiji zmanjšujejo energetski vložek razmnoževanja). Analiza MALDI-TOF MS se je izkazala za dopolnilo analizi regije ITS, saj je potrdila specifičnost proteinskega profila za razlikovanje med vrstami v primerih, ko je bila regija ITS preveč ohranjena za njihovo razlikovanje.Photovoltaic panels are exposed to extreme environmental factors (UV, drought, temperature fluctuations), which complicates but does not prevent the growth of microorganisms (fungi, yeasts, bacteria and archaea) and the formation of biofilms. This biological growth, together with the deposition of surface particles, reduces the efficiency of the panels, as it hinders the access of light to the photovoltaic cells. In this paper, we studied 28 isolates isolated from the surfaces of photovoltaic panels. We cultivated them on different media (MEA, OA, PDA, PNA and DG-18) and at different temperatures (4 ‒ 40 °C). By aligning the nucleotide sequences of the ITS region with the MEGA7 program, constructing the phylogenetic tree and using the BLAST program, and phenotypic characteristics, we classified the isolates among Ascomycota, into the classes Arthoniomycetes, Eurotiomycetes and Dothiodeomycetes, and genera Phaeococcomyces, Neophaeococcomyces, Knufia, Trichomerium, Coniosporium, Dothiora, Constantinomyces, Neocatenulostroma, Capnobotryella, Elasticomyces, Neocatenulostroma, Neospissiomyces, among which eleven species are still unnamed. The relationship among isolates was also determined using the MALDI-TOF MS method. Based on microscopic images, we found that the key features of the studied taxa that affect the growth and survival of the extreme environment of photovoltaic panels are melanization (protects against UV radiation, acts as an antioxidant and participates in thermoregulation), meristematic/microcolonial growth (better temperature tolerance, reduced desiccation), EPS sheaths (facilitated adhesion, a protective network enabling survival during temperature and water fluctuations), specific reproductive structures (endoconidia and arthroconidia reduce the energy input of reproduction). MALDI-TOF MS analysis proved to be a complement to the analysis of the ITS region, as it confirmed the specificity of the protein profile for distinguishing between species in cases where the ITS region was too conserved to distinguish between species
Cervical spine injuries during car collisions with three types of roadside barriers
No full textTraditional methods for assessing vehicle passenger safety in crash tests involving roadside barriers rely on safety indices derived from vehicle kinematic responses. However, this approach may not accurately capture the complex biomechanical stresses exerted on the human body during a collision, raising concerns about the validity and reliability of these indices in accurately evaluating passenger safety. This study investigates the effects of three different types of roadside barriers on vehicle passenger safety using three approaches: (1) assessing compliance with the EN1317 standard based on vehicle kinematics(2) utilizing the Finite Element (FE) Human Body Model (HBM) dummy and Federal Motor Vehicle Safety Standards 208 criteriaand (3) conducting detailed examinations of cervical spine biomechanics. FE simulations, incorporating a biofidelic FE-HBM, are used to evaluate vehicle passenger safety under TB32 impact conditions as specified by the EN1317 standard. The findings reveal that while all barriers effectively contain and redirect the vehicle, the concrete barrier poses the highest risk of occupant injuries, with the highest safety indices and stress levels in the cervical spine, exceeding safe thresholds due to its high lateral stiffness. In contrast, the cable barrier provides the most favorable conditions for vehicle passengers, exhibiting the lowest stress levels and ensuring superior safety performance. The W-beam barrier demonstrates intermediate performance. The analysis also highlights the significance of the tension–flexion loading condition in passenger neck injuries. This condition accounts for 70% of the neck loading intensity for the concrete barrier and 90% for the cable and W-beam barriers, lasting the longest among all neck loading modes. While current safety standards indicate a low risk of occupant injury, detailed FE analysis and cervical spine stress values suggest potential neck injuries, especially with the concrete barrier. These findings emphasize the need to revise current safety standards to include more comprehensive biomechanical evaluations, potentially leading to enhanced road barrier designs and improved road safety standards
Evolution control of cyclic softening of Inconel 718 under isothermal low-cycle fatigue loading by improved calculation of accumulated plastic strain
No full textIn this article, the approach for modelling the stress–strain response of Inconel 718 superalloy under isothermal Low-Cycle Fatigue (LCF) loading using the Prandtl operator approach is improved by introducing an enhanced evolution control of cyclic softening. The proposed improvement consists of an extended calculation of the accumulated plastic strain which now involves an energy conservation step during the calculation. The simulation power of the Prandtl model is especially improved in the area of increasing low plastic strain range magnitudes which are consistently evolving without regard to the variably changing loading regime. The prediction capability of the proposed model is demonstrated especially for block load tests where the highest discrepancies have been observed before the improvement. Evaluation of the agreement between the experimental observations and the simulations shows up to 6 % better agreement using the improved evolution control of cyclic softening
Inverse calibration of out-of-plane shear anisotropy parameters of sheet metal
No full textThe accurate description of sheet metal forming processes such as blanking, riveting, incremental forming, and ironing strongly depends on understanding the material’s through-thickness shear resistance and plastic behavior. A three-dimensional model of plastic anisotropy is required to capture this behavior, but calibrating the out-of-plane shear parameters is often challenging. Researchers frequently assume isotropy or set the in-plane and out-of-plane shear parameters equal. More advanced approaches use a crystal plasticity model, which also requires calibration based on available material texture data. In this work, we introduce an out-of-plane shear test procedure that combines a macromechanical test with digital image correlation to inversely calibrate the shear anisotropy parameters of the YLD2004-18p yield function. This method efficiently characterizes both in- plane and out-of-plane shear anisotropy in medium-thick sheet metals
Transcultural inquiry and the method of philosophical sublation
No full textIn this chapter, I aim to introduce a new method of transcultural philosophical inquiry, tentatively denoted as the method of sublation. It presents an innovative and comprehensive approach to transcultural philosophical analysis. The method offers an innovative framework for engaging with different philosophical traditions, focusing on dynamic interactions and the generation of new insights rather than static comparisons. Applying this method to Chinese and Western philosophies offers a rich avenue for exploration. The name “sublation” itself is derived from Hegelian dialectics, for this method assumes a distinct interpretation rooted in its etymological foundations of elimination, preservation, and elevation. However, it is crucial to note that these three fundamental notions are the sole connections between the post-comparative transcultural sublation and the Hegelian usage of the concept. It is also important to note that the sublation method is rooted in dynamic paradigms of processual philosophy. It veers away from adhering to the formal laws of identity, contradiction, and the excluded third. Unlike the conventional Hegelian model, it does not yield an entirely new, distinct, qualitatively different synthesis as the fusion of two opposing ideas engaged in dialectical interaction. Contrastingly, the zenith of this process manifests in a pivotal stage encompassing a transformative shift that emerges from the tension inherent in the dialectical relation between the two comparata and propels our cognition toward fresh and innovative insights
Acceleration of powder-bed-size thermal simulation considering scanning-path-scale through a pseudo-layer-wise equivalent heat flux model
No full textPart-scale modeling of the temperature field in metal powder bed additive manufacturing (AM) is critical for predicting mechanical properties of the AM-ed parts. Track-by-track heat transfer analysis is impractical due to the extensive number of layers and the intricate design of scan strategies for the heat source, particularly in the fabrication of specimen clusters or parts with complex geometry, where multiple regions in the powder bed are manufactured simultaneously. Many part-scale modeling approaches only focus on the thermal behavior of a single part without considering the thermal interaction from the surrounding parts to reduce computational cost. However, experimental observations have revealed that the temperature distribution along the building direction can vary among samples with identical local geometries. This discrepancy can be attributed to the heating effects from neighboring samples. In this study, we propose an integrated part-scale modeling framework that combines layer-wise equivalent heat flux attribution with layer-wise element activation. Before the layer-wise attribution, we justify the equivalent heat flux of individual layers through high-fidelity track-scale simulations. Unlike traditional heat transfer analysis for single parts, our analysis incorporates heat conduction effects through the powder bed between different fusion zones. The temperature data obtained from each equivalent layer using our approach shows consistency when compared to the experimental observations. This research presents an efficient, physically grounded method for modeling the thermal behavior of large AM specimen clusters, enhancing our understanding of temperature field evolution in AM and supporting the design of optimized scanning path strategies for large samples
Architectural, morphological and contractile parameters of lower limb muscles in older adults
No full textPodatkovni niz vsebuje anonimizirane presečne podatke, zbrane pri 51 starejših odraslih (≥ 60 let) iz Slovenije. Podatki so bili pridobljeni v okviru presečne raziskave, usmerjene v razvrščanje sarkopenije in analizo mišičnih značilnosti.
V podatkovni niz so vključeni demografski podatki (starost, spol), antropometrične meritve ter rezultati meritev mišične jakosti, telesne zmogljivosti, telesne sestave, mišične arhitekture, mišične sestave in kontraktilnih lastnosti mišic. Mišična jakost je bila ocenjena z merjenjem jakosti stiska pesti in testom petkratnega vstajanja s stola. Telesna zmogljivost je bila ocenjena s hitrostjo hoje in testom vstani in pojdi. Podatki o telesni sestavi in mišični masi so bili pridobljeni z električno bioimpedančno analizo in vključujejo pusto telesno maso, skeletno mišično maso, apendikularno skeletno mišično maso ter indekse, prilagojene telesni višini.
Mišična arhitektura je bila izmerjena z ultrazvokom, kjer smo izmerili parametre mišične debeline, kota penacije in dolžine fascikla. Z magnetno resonanco smo pridobili podatke o mišični sestavi in sicer mišični volumen in delež maščobe znotraj mišice. Kontraktilne lastnosti skeletnih mišic so bile ocenjene s tenziomiografijo treh mišic spodnjih okončin, pri čemer so bili zabeleženi parametri zakasnitvenega časa, časa kontrakcije, radialnega premika in hitrosti kontrakcije.
Preiskovanci so bili razvrščeni v skupine sarkopenije po EWGSOP2 in SDOC. Podatki so bili zbrani po standardiziranih protokolih, anonimizirani in opremljeni z metapodatki, kar omogoča njihovo ponovno uporabo v skladu z načeli FAIR.The dataset contains anonymized cross-sectional data collected from 51 older adults (≥ 60 years) from Slovenia. The data were obtained within a cross-sectional study aimed at sarcopenia classification and the analysis of muscle characteristics.
The dataset includes demographic information (age, sex), anthropometric measurements, and results of assessments of muscle strength, physical performance, body composition, muscle architecture, muscle composition, and muscle contractile properties. Muscle strength was assessed using handgrip strength measurement and the five-times sit-to-stand test. Physical performance was evaluated by gait speed and the Timed Up and Go test. Data on body composition and muscle mass were obtained using electrical bioimpedance analysis and include lean body mass, skeletal muscle mass, appendicular skeletal muscle mass, and indices adjusted for body height.
Muscle architecture was assessed using ultrasound, measuring parameters of muscle thickness, pennation angle, and fascicle length. Magnetic resonance imaging provided data on muscle composition, specifically muscle volume and intramuscular fat fraction. Contractile properties of skeletal muscles were evaluated using tensiomyography of three lower-limb muscles, with recorded parameters including delay time, contraction time, radial displacement, and contraction velocity.
Participants were classified into sarcopenia groups according to the EWGSOP2 and SDOC criteria. Data were collected following standardized protocols, anonymized, and accompanied by metadata, enabling reuse in accordance with the FAIR principles