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The effect of Seed Priming with Hydrogen Sulfide on Germination and Biochemical Indicators of Drought Stress in Sunflower Seedlings
Get PDFSuncokret (Helianthus annuus L.), kao četvrta najvažnija uljarica u svijetu, osobito je osjetljiv na nedostatak vode tijekom faze klijanja. Razne tehnike i sredstva primiranja sjemena pokazale su se učinkovitima u poboljšanju klijanja i poticanju ujednačenoga rasta klijanaca naročito u uvjetima abiotskoga stresa. Budući da je dokazano da sumporovodik (H2S) sudjeluje u biljnome metabolizmu, ovo istraživanje ispituje njegov učinak na vijabilnost sjemena suncokreta naklijavanoga u uvjetima sušnoga stresa. Istraživanje je provedeno u kontroliranim uvjetima korištenjem sjemena hibrida Apolon, proizvedenoga u Poljoprivrednome institutu Osijek. Cilj studije bio je utvrditi fiziološku ulogu H2S-a u klijancima uzgojenima iz sjemena koje je prethodno bilo tretirano otopinama natrijeva hidrosulfida (NaHS) i naklijavano u uvjetima sušnoga stresa. Rezultati pokazuju da su klijanci suncokreta najosjetljiviji na osmotski stres tijekom početne faze klijanja, osobito tijekom prva četiri dana. Povećanje razine osmotskoga stresa rastućim koncentracijama PEG- 6000 smanjilo je vijabilnost sjemena testiranoga hibrida, dok su najznačajniji pozitivni učinci primiranja sjemena s donorom sumporovodika, zabilježeni pri niskim (2,5 % PEG-a) i umjerenim (5 % PEG-a) razinama osmotskoga stresa. Rezultati ovoga istraživanja mogu poslužiti kao buduće smjernice za korištenje različitih donatora H2S-a kao sredstva za primiranje sjemena s ciljem poboljšanja otpornosti na sušu u ranim fazama rasta, što je ključno za proizvodnju ove strateški važne uljarice suočene s izazovima značajnih klimatskih promjena.As globally the fourth largest oleaginous plant, sunflower (Helianthus annuus L.) is particularly vulnerable to water shortages during the germination phase. Various seed-priming techniques and agents have been proven to enhance germination and promote a uniform seedling growth, especially during the abiotic stress conditions. Since hydrogen sulfide (H2S) has been documented to be involved in plant metabolism, this study investigates its effects on the sunflower seeds’ vigor when germinating in the drought-stress conditions. The research was conducted under the controlled conditions using the Apolon hybrid seeds, developed by the Agricultural Institute in Osijek. This study’s objective was to determine a physiological role of H2S in seedlings grown from the seeds that had been previously primed in sodium hydrosulfide (NaHS) solutions, having germinated under the drought-stress conditions. The results imply that the sunflower seedlings are most sensitive to the osmotic stress during the initial germination phase, particularly in the first four days. An increase in the level of osmotic stress while rising the concentrations of PEG 6000 reduced the seed vigor of the tested hybrid. The most notable positive effects of seed priming with a hydrogen-sulfide donor were observed at the low (2.5% PEG) and moderate (5% PEG) levels of osmotic stress. This study’s results may provide future guidelines for the use of various H2S donors as a priming agent, aimed at an enhancement of drought resistance in early growth phases, which is crucial for the production of this strategically important oilseed faced by a significant climate change
The Influence of Microbial Bioagents’ Application on the selected Soil Properties in acidic Soils
Get PDFČimbenici koji znatno ograničavaju uspješnu poljoprivrednu proizvodnju u svijetu svakako su pristupačnost fosfora, organske tvari u tlu i pH reakcija tla. Iako se značajne količine fosfora nalaze u tlu, većina je prisutna u biljkama nepristupačnim oblicima. Stoga se ulažu sve veći napori u aktiviranje velikih količina biljkama nepristupačnoga fosfora upotrebom mikroorganizama koji otapaju fosfor. Navedena su dva glavna cilja istraživanja. Prvo, utječe li primjena mikrobiološkoga preparata na promatrana svojstva tla (pH, organska tvar, biljci pristupačan P), i drugo, može li primjena mikrobiološkoga preparata utjecati na povećanje razine fosfora u mikrobnoj biomasi tla. Tri neovisna poljska pokusa postavljena su prema principu slučajnoga bloknog rasporeda sa sljedećim tretmanima u četiri ponavljanja: kontrola „C“, kontrola s mikrobiološkim preparatom „CMA“, gnojidba sa smanjenim unosom fosfora uz mikrobiološki preparat „PMA“ i preporučena gnojidba mineralnim gnojivima „RF“. Uzorci tla analizirani su na pH reakciju, biljci pristupačan fosfor, organsku tvar tla i razinu fosfora u mikrobnoj biomasi tla. Vidljiva povećanja s 3,45 na 5,02 mg P u 100 g tla i s 0,53 na 3,42 mg P u 100 g tla zbog primijene mineralnoga gnojiva utvrđena su na dvije lokacije. Nije zabilježen negativan utjecaj primijenjenoga mikrobiološkog preparata na svojstva tla. Međutim, zabilježena je vrlo snažna korelacija (r = 0,9213 u 2016. i r = 0,9508 u 2017.) između biljci pristupačnoga P i razine P u mikrobnoj biomasi tla. Rezultati ukazuju na činjenicu da su unos fosfora i primjena mikrobiološkoga preparata zajedno s količinom biljci pristupačnoga fosfora u tlu utjecali na razinu fosfora u mikrobnoj biomasi tla.The factors limiting a successful agricultural production worldwide are certainly the availability of phosphorus (P), the soil’s organic matter, and a pH reaction in the agricultural soils. The significant amounts of phosphorus are found in the soils, but approximately 95–99% is present as the insoluble phosphates and cannot be utilized by the plants. Therefore, the increasing efforts are invested to activate the large amounts of plant-unavailable phosphorus by improving a crop’s P use efficiency through the use of phosphorus-solubilizing microorganisms (PSM). The two primary research objectives were stated, as follows: first, to assess whether the applied microbial bioagent impacts the observed soil properties (pH, organic matter, and the available P level), and second, to assess whether a microbial bioagent applied enhances the microbial biomass phosphorus (MBP). The three independent field trials were set up as a randomized blok design, with the following treatments in four replicates: a control, “C“; a control with a microbial bioagent, “CMA“; a reduced P fertilizer with a microbial bioagent, ”PMA“; and a recommended fertilization, “RF.“ The soil samples were analyzed concerning a pH reaction, plant-available phosphorus, soil organic matter, and the microbial biomass P. A visible increase from 3.45 to 5.02 mg P and from 0.53 to 3.42 mg P due to an applied mineral fertilizer was noticed at two locations. No negative impact from applied bioagents was recorded regarding the analyzed soil properties. Very strong relationships (r = 0.9213 in 2016 and r = 0.9508 in 2017) between the available P and the microbial biomass P were stated. The results indicate a fact that the P input and the application of microbial bioagent together with the content of the plant-available phosphorus in the soil influenced the MBP pool
Shopping on a Social Planet: The Mediating Role of Trust
Get PDFPurpose – The purpose of this study is to investigate the factors that influence social commerce (s-commerce) shopping intention employing the Theory of Planned Behavior (TPB). The determinants such social influence, electronic word of mouth (eWOM), and trust on the intention, and social influence and eWOM on trust, as well as the role of trust as a mediator, are examined.
Design/Methodology/Approach – This study makes use of a dataset containing 233 responses from an online survey, selected through non-probability sampling. The partial least squares structural equation modelling (PLS-SEM) with SmartPLS 4.0 was employed to analyze the data and confirm the hypotheses proposed.
Findings and implications – The findings demonstrated empirically that social influence and eWOM significantly contribute to enhancing s-commerce shopping intention. Social influence and eWOM were also found to significantly influence trust. Also, trust was revealed to successfully mediate the association between social influence and intention, as well as between eWOM and intention.
Limitation – The study focuses on shopping intentions in s-commerce but lacks an assessment of actual purchasing behavior, suggesting future research should explore the correlation between these intentions and actual shopping behavior.
Originality – The study substantiated the extension of the TPB framework by enhancing its predictive power in predicting consumer shopping intentions in s-commerce
Enchancing Point of Sale Materials for Consumer Engagement: A Neuromarketing Approach
Get PDFPurpose – In today’s retail environment, shopping is a multi-sensory experience, making it crucial to understand how consumers perceive retail spaces. Retailers can influence consumers’ purchasing decisions by manipulating sensory stimuli. Thus, creating effective advertising materials that enhance shopping intent is vital for both manufacturers and retailers.
Design/Methodology/Approach – This study employed electroencephalography (EEG) to measure unconscious responses to visual marketing stimuli. We assessed emotional valence through prefrontal alpha asymmetry, attention via the alpha/beta activation ratio in the occipital lobe, and cognitive load through theta/beta and alpha activation in the parietal lobe.
Findings and Implications – Our findings indicate that for static advertisements (e.g., posters, floor stickers, wobblers), the most engaging combination of elements includes a headline, a person’s photo, an aesthetically pleasing food image, product packaging, and supporting text. This contradicts prior research suggesting that ads with minimal text and a sleek design have a greater impact. Additionally, promotional pricing displayed in bold had a notable effect on participants.
Limitations – The study adhered to GDPR standards by anonymizing data and using averaged metrics. However, it was conducted in an artificial setting, which may not fully reflect real retail environments. Additionally, the small sample size of 30 participants limits the generalizability of the findings. Technical challenges, such as those associated with EEG usage and participant selection criteria, were effectively addressed.
Originality – This research study stands out by integrating EEG to objectively measure unconscious shopper responses, as opposed to traditional self-reported data. It identifies specific advertisement elements that effectively increase consumer engagement, offering valuable insights into the ways in which to optimize advertising strategies to boost shopper engagement and purchasing intent
Technical and economic aspects in the development of additive technology
Get PDFThis paper studies the importance and development of additive technology through technical and economic
aspects. The technical aspect includes research about the infl uence of surface inclination and layer thickness
on the surface roughness of the produced test samples. Two AM technologies or processes (FDM and SLS)
were used, with the use of three diff erent materials (PLA, PETG and PA12) and two subsequent treatments
(compressed air and glass bead blasting). Surface roughness parameters (Ra, Rz and Rmax) were measured and
analyzed after diff erent manufacturing conditions. Their variability and statistical analysis are presented.
From the obtained results, it is evident that with increasing slope (from 0° to 90°) the values increase to a
maximum (between 10° and 40°), after which they decrease (from 50° to 90°), while increasing the thickness
of the layer causes higher values of roughness parameters. Also, the aim of the paper is to determine the
economic profi tability of the used procedures, that is, the impact of the manufacturing procedures on the price
of the product. Modern and innovative materials and technologies are used in the research. By using innovative
technologies, we infl uence on sustainable development, which speaks of the fact that we need to meet our
needs with quality, while taking care that the generations that come after us also have this opportunity
Aminopyridine Schiff bases as eco-friendly corrosion inhibitors for carbon steel in acidic media: experimental and quantum chemical insights
Get PDFMaterial degradation has received a lot of attention from the scientific community as a serious problem. However, a major barrier to the application of effective corrosion treatment is the ban on the use of inhibitors containing dangerous substances. In addition to being efficient corrosion inhibitors, Schiff bases offer pharmacological, anti-inflammatory, antibacterial, anti-cancer, and antioxidant qualities. In this experiment, two types of aminopyridine Schiff bases were used to investigate the corrosion resistance of carbon steel (C-steel) in an environment containing 1 mol L-1 HCl. The study used weight loss and electrochemical assays to assess the corrosion-inhibiting effectiveness of two Schiff base derivatives (HAPT and HHTA). It was found that the inhibitory efficiency rises with increasing HAPT and HHTA dosages and falls with increasing temperature. HAPT and HHTA showed impressive corrosion inhibition rates of 93.4 and 95.2 %, respectively. The enhanced inhibitory efficiency results from the significant adsorption of HAPT and HHTA molecules on the C-steel surface through chemisorption and physisorption in compliance with the Langmuir adsorption isotherm. The production of an inhibitory film on the C-steel substrate was confirmed by the results of the scanning electron microscope. Density functional theory and molecular dynamics computations in quantum chemistry were used to identify the adsorption of HAPT and HHTA at the steel/solution interface
Solid State Characterization of Croatian Wine Grape Pomace by NMR and ATR-FTIR
Get PDFGrape pomace (GP), the solid residues remained after production of the continental and coastal Croatian red wines, has been studied by solid-state NMR and ATR-FTIR methods. After collection, drying and milling, GP samples have been analysed by IR spectroscopy and characteristic vibrational bands have been assigned. The observed differences in some functional group vibrations have been detected for continental and coastal GPs as well as for different vintages. ¹³C cross-polarization magic angle spinning (CP MAS) NMR experiments provided further information on chemical composition of GPs and percentages of different compounds present in the samples such as polysaccharides and phenolic compounds. ³¹P MAS spectra gave valuable quantitative information on the phosphorus content. The GPs from the continental varieties contain much larger portion of phosphorus compared to coastal ones, which is important for their potential use as an attractive raw material and value-added compounds for industrial applications
Independence of the Judiciary Versus Uniformity of Case Law in the Legal System of the Republic of Croatia
No full textUjednačena sudska praksa, u smislu pravne predvidivosti sudskih odluka, sastavni je dio pravne sigurnosti kao jednog od ključnih izraza vladavine prava. Vladavina prava predstavlja jednu od temeljnih vrijednosti Europske unije te čini dio ustavnog identiteta Republike Hrvatske. Ipak, ovaj ideal pravnog sustava ne smije ugroziti drugo temeljno načelo vladavine prava – neovisnost sudstva. U tom kontekstu, u ovom se radu istražuju i ocjenjuju postojeći i donedavno primjenjivani mehanizmi ujednačavanja sudske prakse u pravnom sustavu Republike Hrvatske, s posebnim osvrtom na njihov utjecaj na neovisnost sudstva.Uniform case law, as an element of legal predictability, constitutes a part of legal certainty, which reflects the rule of law. The rule of law is one of the fundamental values of the European Union and forms part of the constitutional identity of the Republic of Croatia. However, this ideal of any legal system must not jeopardize another essential aspect of the rule of law – the independence of the judiciary. This paper explores and evaluates both current and recently discontinued mechanisms for the unification of case law within the legal system of the Republic of Croatia, with a particular focus on their impact on judicial independence
YOLOv7-Driven Visual Inspection System for Edge Banding Defects in Panel Furniture
Get PDFCurrent quality inspection of edge banding in panel furniture heavily relies on manual screening, which is labor-intensive, subjective, and inefficient. To address this challenge, we propose a YOLOv7-based visual inspection system by integrating machine vision and deep learning. A dataset containing 1,887 images of six defect types (e.g., open glue, chipping, uneven trimming) was constructed, with annotations generated via LabelImg. Data augmentation strategies (rotation, scaling, cropping) were applied to enhance model robustness. The YOLOv7-Tiny model achieved a mean average precision (mAP) of 74.8 % at 57.63 FPS, outperforming traditionalmethods and demonstrating superior speed-accuracy trade-offs. Experimental results on real-time industrial camera data validated the system’s capability to detect defects with high precision (82.1 %) and recall (75.4 %). This framework significantly reduces production costs and provides a scalable solution for automated quality control in furniture manufacturing
Associations between physical fitness and mental toughness in competitive adolescent dance sport athletes
Get PDFMental toughness (MT) is considered a major contributing factor for performing at high level in competitive sporting events. Despite its importance, few studies have examined probable correlations between MT and physical fitness (PF). Since both constructs are equally important in sport, it is necessary to establish whether MT may be correlated with PF. Two-hundred and nineteen competitive adolescent dancers took part in the study (mean age: 16.8±1.4 years; height: 169.5±8.7 cm; body mass: 61.4±9.2 kg; 58% girls). PF was assessed by the body mass index (body composition), standing broad jump (muscular fitness), sit-ups in 30 seconds (repetitive strength), 10x5 shuttle run (agility), sit-and-reach test (flexibility), and the 20-m shuttle run test (cardiorespiratory fitness). The Sports Mental Toughness Questionnaire (SMTQ) was used to evaluate MT. In boys, MT was positively correlated with standing broad jump (r = 0.54), sit-ups in 30 seconds (r = 0.56), the 20-m shuttle run test (r = 0.61) and the sit-and-reach test (r = 0.34) and negatively correlated with the 10x5 shuttle run test (r = -0.43). In girls, MT was also positively correlated with standing broad jump (r = 0.48), sit-ups in 30 seconds (r = 0.46), the 20-m shuttle run test (r = 0.53) and the sit-and-reach test (r = 0.30) and negatively correlated with the 10x5 shuttle run test (r = -0.32). Regardless of sex, no significant correlations between MT and body composition were observed (r = 0.12 in boys and r = 0.10 in girls). This study shows that PF parameters are correlated well with MT. This would suggest that both physical and psychological components need to be investigated to examine potential co-existence between them. Also, interventions aiming to enhance MT throughout PF are warranted