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The Influence of Early Cycling Initiation on Active Mobility, Cycling Behaviours and Safety Outcomes
No full textAlthough cycling is widely renowned for its benefits to transport sustainability and individual health, the impact of cycling initiation age on cycling behaviours and safety outcomes remains underexplored in the scientific literature. The present study aimed to investigate the relationship between the age of initiation and self-reported cycling behaviours, safety skills and willingness to increase cycling participation. For this purpose, we used the data provided by 1,741 cyclists from five Balkan countries. Overall, no significant differences in onset ages were found between male and female riders. Regarding self-reported cycling behaviour, individuals who started cycling at an earlier age were less prone to unintentional risky behaviours and consistently reported better knowledge of traffic rules. Notably, earlier starters are those who currently engage in longer and more sustained cycling trips. However, they were also less likely to wear a helmet and more likely to engage with connected devices while cycling. This suggests that while the relationship between cycling onset ages and subsequent riding outcomes is relatively clear, it is neither tautological nor linear, highlighting the ongoing need for safety literacy initiatives. On a practical level, these findings underline the need for strategies that promote early cycling engagement while fostering sustained growth in active mobility and safer cycling practices
Ferrocenium tetrachloromagnesate modified MWCNTs electrode for detection of Bi3+ at the trace level in polluted aqueous solutions
No full textThis study presents the fabrication of a ferrocenium tetrachloromagnesate (FTM) modified multi-walled carbon nanotubes (MWCNTs) electrode for the voltammetric determination of bismuth ions (Bi3+) in aquatic environments. The FTM was synthesized from the reaction of magnesium chloride with ferrocene. The incorporation of FTM, a redox-active species, was shown to markedly improve electron transfer kinetics and overall electrochemical conductivity. Structural and morphological characterizations via Fourier transform infrared spectroscopy, transmission electron microscopy, energy dispersive x-ray, field emission scanning electron microscopy and X-ray diffraction confirmed the successful embedding of FTM within the electrode matrix. Electrochemical assessments using cyclic voltammetry, electrochemical impedance spectroscopy, and chronocoulometry revealed that a 10 wt.% FTM loading provided the most optimal charge transfer and interfacial behaviour. Differential pulse stripping voltammetry further demonstrated the high sensitivity of the developed electrode, achieving an ultralow detection limit of 0.543 nM with two broad linear ranges of 1.0 nM to 0.1 and 1.0 µM to 0.1 mM for Bi3+. The sensor also exhibited remarkable reproducibility (RSD 8.67 %) and stability (RSD 7.77 %). Furthermore, excellent selectivity toward Bi3+ was maintained in the presence of potentially interfering ions such as Mn2+, La3+, Ni2+, Li+, Zn2+, Fe2+, Cd2+, Cu2+, Er2+ and Pb2+. Real water-sample analyses yielded recoveries of 89 to 104 %, confirming the practical feasibility of the electrode for environmental monitoring
Fabrication of iridium-gold nanocomposite for the detection of selective serotonin reuptake inhibitors
No full textA comprehensive study of the development of a novel electrochemical sensor based on iridium-gold nanocomposite (IrAuNPs) modified electrodes for the detection of antidepressants, paroxetine (PRX) and citalopram (CIT) was conducted. The sensing platform, based on a glassy carbon electrode, was modified by drop-casting IrAuNPs, which allowed for enhanced conductivity. IrAuNPs, along with their counterparts iridium nanoparticles (IrNPs) and gold nanoparticles (AuNPs), were synthesized from coffee waste extract (CWE) via complete green chemistry. The physicochemical properties of synthesized nanomaterials were characterized using ultraviolet-visible spectroscopy, dynamic light scattering, high-resolution transmission electron microscopy, Fourier-transform infrared spectroscopy, cyclic voltammetry and square wave voltammetry. Results showed that the CWE could reduce the respective metallic salts to form mostly near-spherical to spherical IrAuNPs, IrNPs and AuNPs with core sizes ranging from 2.02 nm to 13.27 nm. The electrochemical sensor could determine PRX and CIT in the concentration ranges of 20 to 200 nM and 1 to 10 µM, with detection limits of 0.072 nM and 0.085 µM, respectively. The sensor showed a recovery of 86 to 115.1 %. The proposed sensor demonstrated good precision and accuracy, with excellent sensitivity and selectivity for drug identification in a rapid analysis time, which is crucial for applications in biological matrices
Progress in eco-friendly aerospace coatings: the future beyond chromates
No full textAluminium alloys have a good strength-to-weight ratio and low density, but they are not impervious to corrosion. Therefore, it is necessary to evaluate their corrosion performance in the atmospheric environment. Paints are typically used to prevent corrosion on aluminium alloys. A conversion or anodized layer, an inhibitor/metal-doped primer, and a polyurethane topcoat are used as 3-layer coatings for aluminium alloy corrosion protection in the aerospace industry. However, major modifications have been made to the protection of aluminium alloys against corrosion as a result of environmental issues. REACH, a European regulation, has significantly altered some finishing procedures for aluminium alloys by prohibiting or restricting the use of Cr(VI)-based compounds, such as chromate conversion, chromic acid anodizing, and chromate sealing. Searching for alternatives to Cr has yielded intriguing results. For many years, sol-gel-based hybrid coatings have been a promising alternative to pretreatment and primer layers, with promising results. This review discusses the current development and advancement in chrome-free corrosion-resistant layer coating systems for aluminium alloys
Influence of Urban Underground Spiral Ramp Curve Design on Vehicle Running Performance
No full textUrban underground spiral ramps’ continuous curves and the monotonous tunnel environment increase driving safety risks and reduce vehicle stability. To clarify the influence of road geometric alignment parameters on vehicle acceleration in urban underground spiral ramp curves, a real vehicle test was conducted on the Jiefangbei Underground Ring Road - Hongyamen Underground Road in Yuzhong District, Chongqing, China. On-board instruments collected acceleration data from 20 drivers to analyse how curve radius and angle affect the vehicle’s three-axis acceleration. The results show that: (1) The exit acceleration of the spiral ramp curve is positively correlated with the curve radius and negatively correlated with the turning angle, while entrance deceleration exhibits the opposite trend. (2) Lateral acceleration is negatively correlated with curve radius but positively correlated with turning angle. (3) Vertical acceleration increases with curve radius on upward curves and decreases on downward ones; the opposite occurs with turning angle. (4) Vehicle acceleration differs significantly under varying radii and turning angles. The average exit acceleration is higher for ordinary-radius (or small turning angle) curves than for small-radius (or large turning angle) curves, while the average lateral acceleration exhibits the opposite trend. These findings reveal passenger car driving behaviour characteristics on urban underground spiral ramps, supporting future curve geometric design and safety studies
Experimental Study on the Aerodynamics of a Hybrid Dolphin Airfoil
No full textThis paper presents an experimental study of the aerodynamic characteristics of a new hybrid Dolphin airfoil, designated NA-DEL 2415. This airfoil is part of a novel family of seven hybrid Dolphin airfoils obtained through modification of the leading edge of the original Dolphin airfoils for the assumed standard roughness case. These hybrid airfoils have demonstrated improved aerodynamic characteristics compared with the NACA series and superior characteristics relative to Taposu's original Dolphin airfoils. Experiments presented in this paper were conducted in the subsonic wind tunnel of the University of Belgrade - Faculty of Mechanical Engineering. The NACA 2415, Dolphin 2415, and NA-DEL 2415 airfoils were tested under identical conditions, at the same Reynolds number, with free boundary layer transition. The experimental results confirmed the general NA-DEL aerodynamic advantages previously obtained by CFD investigations at a higher Reynolds number. The development and experimental investigation of the NA-DEL 2415 airfoil represents a novel contribution to the field, offering both scientific innovation and significant potential for operational application in general aviation and unmanned aerial vehicles
Iterative Decoupler Design Method for TITO Processes
No full textIn this paper, possibilities for iterative tuning of the decoupler for TITO (two inputs and two outputs) process are investigated. The developed algorithm is based on getting decouplers terms iteratively, taking into account previously defined limits of response quality indicators. The effectiveness of the designed new method has been presented in four examples using simulations. It enables similar performances as computational methods for decoupler design from the literature, but without knowing of process mathematical model. So, that is a less complicated and less time-consuming method, which can be used for adding a decoupler to an already controlled process during its functioning and also for improving terms of an existing decoupler
Philosophers - Rectors of the University of Zagreb
No full textSveučilište u Zagrebu naše je najstarije i zasigurno najuglednije sveučilište. Utemeljeno je u drugoj polovici 17. stoljeća – točnije 23. rujna 1669. godine, te neprekidno djeluje sve do današnjega dana. 350. obljetnica Sveučilišta u Zagrebu obilježena je 2019. godine. Sveučilište je obnovljeno i kao takvo otvoreno 19. listopada 1874. godine. Istražujući popis rektora Sveučilišta u Zagrebu od 1874. godine pa sve do danas bilo je ukupno osam rektora koji su bili i filozofi. Njih smo u ovom radu predstavili kronološkim redom: Antun Kržan (treći rektor: 1876. – 1877.); Franjo Marković (osmi rektor: 1881. – 1882.); Đuro Arnold (dvadeset i šesti rektor: 1899. – 1900.); Antun Bauer (trideset i treći rektor: 1906. – 1907.); Stjepan Zimmermann (pedeseti rektor: 1923. – 1924.); Albert Bazala (pedeset i peti rektor: 1932. – 1933.); Ivan Supek (sedamdeset i sedmi rektor: 1968. – 1972.) te, konačno, Predrag Vranicki (sedamdeset i osmi rektor: 1972. – 1976.). Uzimajući u obzir sve rektore koji su bili i filozofi, onda možemo reći da su došli s dva fakulteta i to: Mudroslovni/filozofski i Bogoslovni fakultet. Svako Sveučilište, pa tako i Zagrebačko, po svojem temeljnom poslanju treba težiti otvorenosti duha novim znanstvenim spoznajama. Osim toga, potrebno je na Sveučilištu uvažavati i duh različitosti te njegovati uključivost te, uza sve razlike, promicat i nepokolebljivo zastupati međusobno uvažavanje. Zato nam je želja da na časnu rektorsku stolicu Sveučilišta u Zagrebu ponovno zasjednu kako ugledni profesori s Katoličkog bogoslovnog fakulteta, tako i oni s Filozofskog fakulteta te da svojim znanjem i sposobnošću isto to Sveučilište povedu u bolju budućnost.University of Zagreb is our oldest and certainly our most prestigious university. It was founded in the second half of the 17th century—more precisely on September 23, 1669—and has operated continuously up to the present day. The 350th anniversary of the University of Zagreb was celebrated in 2019. The University was restored and reopened on October 19, 1874. By examining the list of rectors of the University of Zagreb from 1874 to the present day, there have been a total of eight rectors who were also philosophers. In this paper, we present them in chronological order: Antun Kržan (third rector: 1876–1877); Franjo Marković (eighth rector: 1881–1882); Đuro Arnold (twenty-sixth rector: 1899–1900); Antun Bauer (thirty-third rector: 1906–1907); Stjepan Zimmermann (fiftieth rector: 1923–1924); Albert Bazala (fifty-fifth rector: 1932–1933); Ivan Supek (seventy-seventh rector: 1968–1972); and finally Predrag Vranicki (seventy-eighth rector: 1972–1976). Taking into account all rectors who were also philosophers, we can say that they came from two faculties: the Faculty of Philosophy (Mudroslovni/Filozofski) and the Faculty of Theology (Bogoslovni). Every university, including the University of Zagreb, by its fundamental mission should strive for openness of spirit toward new scientific insights. Moreover, it is necessary at the University to respect the spirit of diversity and to cultivate inclusiveness, and—despite all differences—to promote and firmly uphold mutual respect Therefore, it is our wish that the honorable rector’s chair of the University of Zagreb once again be occupied both by distinguished professors from the Catholic Faculty of Theology and by those from the Faculty of Philosophy, so that with their knowledge and abilities they may lead this University toward a better future
SPECIES-SPECIFIC EVIDENCE OF STRUCTURAL CHANGE IN PORTUGUESE FISHERIES: A 30-YEAR ANALYSIS OF CFP REFORM INFLUENCE
No full textOva studija pruža prvu nacionalnu, po vrstama razvrstanu kvantitativnu procjenu strukturnih promjena u portugalskom morskom ribarstvu tijekom tri desetljeća (1995. – 2024.), što se podudara s velikim reformama Zajedničke ribarstvene politike (ZRP) Europske unije. Koristeći godišnje podatke o iskrcaju za 47 vrsta, primijenjena je Spearmanova korelacija rangova za otkrivanje dugoročnih monotonih trendova između godine i volumena iskrcaja. Rezultati otkrivaju sveprisutni pad: 26 vrsta (55,3%) pokazalo je značajne negativne trendove (ρ i do -0,953, pThis study provides the first national, species disaggregated quantitative assessment of structural changes in Portuguese marine fisheries over three decades (1995–2024), coinciding with major reforms of the European Union’s Common Fisheries Policy (CFP). Using annual landings data for 47 species, Spearman rank correlation was applied to detect long term monotonic trends between year and landing volume, a non parametric approach robust to non normality, zeros, and outliers. Results reveal a pervasive decline: 26 species (55.3%) exhibited significant negative trends (ρ as low as −0.953, p
Anti-inflammatory potential of plant-derived extracellular vesicles from Solanum nigrum L. integrated in gelatine-dopamine hydrogel on RAW 264.7 and MC3T3 cells
No full textBackground and purpose: Plant-derived extracellular vesicles (PDEV) from Solanum nigrum L. fruit show promise as a cell-free regenerative and inflammatory therapy for bone defects due to their anti-inflammatory properties. However, challenges such as storage stability and targeted delivery efficiency remain in PDEV's applications. Strategies such as lyophilization and injectable hydrogel delivery systems offer potential solutions. Experimental approach: In this study, lyophilized PDEVs derived from Solanum nigrum L. berries were incorporated into a thermosensitive injectable gelatine-dopamine (Gel-Dop) hydrogel and evaluated by in vitro for their anti-inflammatory potential using MC3T3 pre-osteoblast cells and RAW 264.7 macrophage cells. Key results: The isolated PDEVs show a spherical morphology, an average size of approximately 132.6 nm, a polydispersity index of 0.197, and a protein concentration of 509 μg mL-1. These PDEVs were efficiently internalized by MC3T3 and RAW 264.7 cells after 12 hours of incubation and showed no cytotoxic effects at concentrations up to 10 μg mL-1. The release profile confirmed that the hydrogel effectively released the PDEVs, which remained non-toxic and were internalized by cells after 12 hours of incubation. Subsequently, treatment of lipopolysaccharide (LPS) stimulated MC3T3 and RAW 264.7 cells with PDEVs led to a reduction in IL-6 protein expression. Conclusion: These findings suggest that lyophilized PDEVs from Solanum nigrum L. berries, when incorporated into Gel-Dop hydrogel, hold promise for future development as an anti-inflammatory agent in bone therapy. This study is the first to characterize and incorporate lyophilized PDEVs from Solanum nigrum L. into thermosensitive injectable Gel-Dop hydrogel and demonstrate their anti-inflammatory potential through the suppression IL-6 expression in LPS-stimulated MC3T3 and RAW 264.7 cells