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CHANGES IN THE PROPORTION OF FISH SPECIES CAUGHT BY ARTISANAL FISHERS IN THE CROATIAN SECTION OF THE SAVA RIVER
No full textBroj gospodarskih ribara, a posljedično i njihov ulov u rijeci Savi kontinuirano padaju kroz dva desetljeća. Prosječna masa pojedinih vrsta se također značajno promijenila. Stoga je cilj ovoga rada istražiti moguće promjene u udjelu biomase najvažnijih taksona u ulovu. Većina vrsta pokazala je velike varijacije u ulovu iz godine u godinu, bez jasnog trenda (p˃0,05). Najveće oscilacije, s CV većim od 90% utvrđene su kod Acipenser ruthernus, Cyprinus carpio, Leuciscus aspius i alohtonih vrsta. CV između između 41% and 73% su imali Esox lucius, Leuciscus idus, Silurus glanis i Sander lucioperca. Najmanje varijacije udjela u ulovu su utvrđene za Abramis brama (37,77%) i ostale autohtone vrste (najzastupljenija Rutilus virgo), (33,43%). Ova dva taksona su imali značajne suprotne trendove (R2=0,34; p˂0,01), a zajednički su u biomasi ulova zastupljeni s udjelom od 67,03 %.The number of artisanal fishers, and consequently their catch, in the Sava River has declined significantly over the past two decades. The average weight of some species has also changed significantly. Therefore, the aim of this paper is to investigate possible changes in the biomass proportion in the catch of the most important taxa during this period. Most of the investigated species showed considerable variation in catch from year to year, but without a clear trend (p > 0.05). The largest fluctuations, with a coefficient of variation (CV) over 90%, were found in Acipenser ruthenus, Cyprinus carpio, Leuciscus aspius and allochthonous species. Esox lucius, Leuciscus idus, Silurus glanis and Sander lucioperca had CVs between 41% and 73%. The smallest variations in the proportion of catch were recorded for Abramis brama and other autochthonous species (the most abundant being Rutilus virgo), with CVs of 37.77% and 33.43%, respectively. These two taxa also showed significant opposite trends (R² = 0.34; p < 0.01) and had a combined average biomass proportion of 67.03%
Novel stirring method for small-scale dissolution test: Rotating vessel method
No full textBackground and purpose: In the compendial dissolution test, the overhead rotating paddle method (ORP) has been used for stirring, whereas the magnetic stirring bar method (MSB) has been employed for small-scale dissolution tests, such as the μDISS ProfilerTM (μDISS). Previous reports have indicated that differences exist in the precipitation profiles of a drug between ORP and MSB, because the latter causes contact-induced nucleation. However, it has been difficult to use an ORP and an in situ UV probe simultaneously in μDISS. In this study, a novel stirring method, the rotating vessel method (RV), was developed for μDISS. The dissolution and precipitation profiles of model drugs in RV-μDISS were then compared with those in MSB-μDISS, as well as with the results of conventional dissolution tests using an ORP. Experimental approach: In RV-μDISS, a small paddle (approximately 1/4 of the conventional paddle) was fixed to the UV probe, and the glass vessel was rotated to produce a flow pattern similar to that of ORP. The dissolution and bulk-phase precipitation tests were performed for ibuprofen sodium (IBU Na) and carbamazepine (CBZ), respectively, using RV-μDISS and MSB-μDISS, as well as ORP with the conventional vessel (500 mL, for IBU Na) (CV) or the mini-vessel (50 mL, for CBZ) (MV). Key results: The dissolution rate of IBU Na was similar in all methods. Rapid precipitation of crystalline IBU free acid was observed in the MSB-μDISS method. In contrast, no crystalline precipitation was observed in RV-μDISS and ORP-CV, and the drug phase-separated as a liquid (oil) phase (liquid-liquid phase separation). The precipitation rate of CBZ in RV-μDISS was similar to that in ORP-MV, but slower than that in MSB-μDISS. Conclusion: The precipitation profile in RV-μDISS was close to those in ORP-CV and ORP-MV. RV-μDISS would be a useful tool for the assessment of the precipitation profiles of drugs
Aktualnosti iz projekta “Znanje+Kreativnost = STEM Inspiracija”: Obavijest o dobivenom projektu – STEM budućnost počinje sada: Projekt “Znanje + Kreativnost = STEM Inspiracija” dobio potporu Europskog socijalnog fonda plus!
No full textAktualnosti iz projekta “Znanje+Kreativnost = STEM Inspiracija”: Poziv na sudjelovanje na stručnom skupu “Inovacije u STEM-u: Ključevi napretka kroz zečenu tranziciju i digitalizaciju"
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Cortisol as a biomarker for stress: A review of sampling methods in small ruminants
No full textCortisol is a key biomarker of stress and hypothalamic-pituitary-adrenal (HPA) axis activity in an organism. Different biological samples are used for measuring cortisol levels, such as blood, saliva, milk, urine, faeces, and hair. Blood plasma or serum cortisol measurements are widely applied to quantify acute stress response in farm animals, but stress sampling and rapid hormonal changes can undermine accuracy in results. Saliva has proven to be a reliable alternative sample for assessing free cortisol, offering a less stressful approach with minimal triggering of the stress response. Cortisol determination in milk is a non-invasive method of limited applicability for lactating ruminants, though physiological parameters such as milk yield and stage of lactation can influence its interpretation. Concentrations of cortisol in urine reflect the cumulative cortisol secretion over time, making it a valuable indicator of chronic stress, though research on small ruminants remains limited. Similarly, faecal cortisol metabolites offer a non-invasive means of assessing adrenal activity with delayed but integrated hormonal fluctuations. Hair and wool analysis provide insight into long-term stress exposure, though factors such as seasonal variation and local synthesis complicate its application. This review highlights the strengths and challenges associated with different cortisol sampling methods, emphasising the importance of multiple biological sample approaches for accurate welfare assessments in ruminants
UTJECAJ ZELENIH OBVEZNICA NA SMANJENJE EMISIJE UGLJIKA: ANALIZA PANEL PODATAKA
No full textThe main goal of governments is to achieve economic stability as well as meeting development objectives through using fiscal policy tools. In this direction, many countries have turned to alternative renewable resources to meet their growing energy needs and reduce the level of carbon (CO₂) emissions that cause air pollution and climate change. In this context, green bonds fund projects and investments aimed at environmental protection and climate change mitigation. This paper focuses on investigating the relationship between CO₂ emissions and green bond issuances. In this context, panel data regression analysis was applied. In this method, collective data, regarding green bond issuance of 31 different countries throughout 2014-2022 period, were utilized. The analyses reveal that green bond issuances have an impact on CO₂ emissions, and this impact is significant and negative, while the effects of urbanization and GDP growth rate are significant and positive.Temeljni cilj vlada jest postizanje ekonomske stabilnosti i ispunjavanje razvojnih ciljeva primjenom instrumenata fiskalne politike. U tom smislu, mnoge su se zemlje okrenule obnovljivim izvorima kako bi zadovoljile svoje rastuće energetske potrebe i smanjile razinu emisija ugljika (CO₂) koje doprinose onečišćenju okoliša i klimatskim promjenama. U tom kontekstu, zelene obveznice služe financiraju projekata i ulaganja usmjerenih na zaštitu okoliša i ublažavanje klimatskih promjena. Glavna svrha ovog rada jest ispitati odnos između izdavanja zelenih obveznica i emisija CO₂. U tu svrhu primijenjena je regresijska analiza panel podataka na uzorku od 31 zemlje u razdoblju od 2014. do 2022. godine. Rezultati analize pokazuju da izdavanje zelenih obveznica ima negativan i statistički značajan utjecaj na emisije CO₂, dok su utjecaji urbanizacije i stope rasta BDP-a pozitivni i statistički značajni
Application of Photogrammetry in Agriculture with an Emphasis on Close-Range
No full textIn contemporary agricultural practices and technological advancements, the paramount focus is on enhancing productivity and operational efficiency. This entails the effective management of digital resources like obtained from photos while minimizing costs. Through the application of close-range photogrammetry and various specialized software (Agisoft Metashape, CloudCompare, MicMac, Pix4Dmapper and OpenDroneMap), farmers can effectively and accurately monitor vegetation indices and generate three-dimensional models, thereby enhancing the optimization of their agricultural practices. Photogrammetric softwares enable creating 3D models, their interaction with the processing procedure, production of point clouds, image mergin from drone photos and an automatic extraction of DEMs. The emphasis of the paper is on the great potential of photogrammetry with the main goal to improve modern agriculture such as cost reduction, precision and accuracy, data collection and similar to. Paper is based on examples of practice and field work in the agricultural sector around the world
Development of Solar-Powered Herbicide Spraying Robot Controlled Using a Mobile Application
No full textThe evolution of digital agriculture is significantly influenced by agricultural robots, which contribute uniquely and present numerous benefits to the efficiency of farming operations. The trend of population explosion that the world is experiencing mandates the need to provide an adequate food supply. Hence, a conscious effort must be taken to eradicate weeds on the farmland. This research explored the use of technology to implement a weed elimination system by combining IOT and wireless navigation while also implementing solar energy which encourages green energy initiatives. The research encompasses an unmanned ground vehicle driven by four wheels and controlled by a mobile application that establishes a Bluetooth connection with the system. The ground vehicle was tested to establish the solar charging efficiency, the mobile application connection and operation and the ground vehicle spraying action. The result obtained at the end of the research showed that remote controlled operation of agricultural robots can help improve production efficiency while also reducing environmental pollution with solar charging systems
Ultrasound-enhanced water electrolysis for hydrogen production: Mechanisms, metrology and energy metrics
No full textUltrasound intensifies hydrogen production in water electrolysis cells by thinning boundary layers, accelerating bubble detachment, and, in tuned windows, modulating cavitation chemistry, yet cross-study claims remain difficult to compare. Focusing on ultrasound-enhanced water electrolysis (sono-electrolysis), this review aligns reporting with IEC 61161 (radiation-force acoustic power) and IEC 62127-2:2025 (hydrophone calibration); requires delivered acoustic intensity at the electrode, Idel / W·cm⁻², with stated traceability; pairs isothermal control with uncertainty budgets; and benchmarks performance using Δ-metrics: Δj (current-density gain at fixed cell voltage), Δη (cell voltage/overpotential reduction at fixed current density) and ΔHPR (hydrogen production rate gain at matched electrical input), together with specific energy consumption (SEC,kWh·kg⁻¹ H₂). A window-based synthesis indicates that, under isothermal operation, 20 to 40 kHz with delivered intensity ≈0.2 to 1.0 W·cm⁻² reproducibly yields Δj ≈ 15 to 30%, Δη ≈ 40 to 120mV, ΔHPR ≈ 10 to 30 %, and net SEC improvements of ~8 to 12 % when auxiliary loads are included, whereas at higher dose (Idel ≈ 1.0 to 1.6 W·cm⁻²) non-uniform fields, cloud shielding, and heating can saturate or reverse benefits. To prevent metric conflation, hybrid sono-hydrogen routes are reviewed separately. The review concludes by proposing a minimum reporting set-frequency, waveform/duty and pulse repetition frequency, Idel (traceability/uncertainty), geometry/stand-off, electrolyte and dissolved gas, bulk temperature and runtime, gas metrology with temperature/pressure corrections, SEC boundaries and replicates/statistics, and by outlining priorities for operando cavitation-electrochemistry co-registration, geometry/void-fraction-aware scale-up, and durability under combined fields, to support reproducible, energy-accounted, and comparable studies across laboratories