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LINKING ECONOMIC COMPLEXITY AND THE ENVIRONMENT: THE CASE OF THE EUROPEAN UNION
No full textEnvironmental damage has been a topic of great importance to the European Union since the European Green Deal was approved in 2020, with the goal of Europe becoming the first continent with net-zero emissions by 2050. Economic complexity is a concept that has gained relevance because it explains the productive structure of countries. There is literature that links economic complexity with environmental degradation. There is a gap of knowledge regarding how the productive structure of the European Union member states affects the environment. The paper aims to quantify the effect of economic complexity on the environment at the European Union through a nonlinear function. To achieve this, a panel data model with fixed effects was used, as well as a nonlinear functional model to quantify the effect of the Economic Complexity Index on CO2 emissions. The results show that the relationship between the Economic Complexity Index and CO2 emissions is U-shaped, and the same holds whether fossil fuels or the energy intensity index are used as measures of environmental degradation
A note on the Chebyshev inequality and related inequalities for Fibonacci numbers
No full textSome new results for Fibonacci sequence concerning the Chebyshev type inequalities are proved
Utjecaj botaničkog podrijetla i prerade na antimikrobnu aktivnost pčelinje peludi
No full textBee pollen is a nutrient-rich bee product and natural food supplement that contains proteins, vitamins, minerals and bioactive compounds, offering antioxidant, anti-inflammatory, immunostimulatory and antimicrobial activity. Numerous studies have confirmed the in vitro antimicrobial activity of both polyfloral and monofloral bee pollen. Monofloral bee pollen had a more stable chemical composition and more consistent sensory and biochemical properties, making it more suitable for various applications. This has led to a growing number of studies investigating its antimicrobial potential. Antimicrobial activity of bee pollen is influenced by natural factors such as the botanical and geographical origin, seasonal variation and beekeeping practices. The outcomes of in vitro testing also depend on choices related to extract preparation, solvent type, microbial strains and the method employed to measure antimicrobial activity. Another challenge is the limited bioavailability of bioactive compounds, restricted by the degradation-resistant outer layer of bee pollen, named the exine. The wall can be partially disrupted through processing methods that break it and enhance its nutritional and functional properties. This review provides a comprehensive overview of published studies on the antimicrobial activity of monofloral bee pollen. It summarizes the most frequently investigated botanical species and bacterial strains, highlighting those with the most promising antimicrobial results. Additionally, it examines the processing methods of pollen, comparing their effectiveness and the changes in antimicrobial activity before and after processing. The review identifies the plant species, solvents and methods that yield strong antimicrobial activity, emphasizing their potential in the broader effort to standardize high quality parameters for bee pollen.Pčelinja pelud je hranjivi pčelinji proizvod i prirodni dodatak prehrani koji sadržava proteine, vitamine, minerale i bioaktivne spojeve, te ima antioksidacijski, protuupalni, imunostimulacijski i antimikrobni učinak. Brojna su istraživanja potvrdila antimikrobnu aktivnost poliflorne i monoflorne pčelinje peludi in vitro. Monoflorna pčelinja pelud ima stabilniji kemijski sastav te ujednačenija senzorska i biokemijska svojstva, što ju čini prikladnijom za različite primjene. To je dovelo do porasta broja istraživanja usmjerenih na ispitivanje njezinog antimikrobnog potencijala. Na antimikrobnu aktivnost pčelinje peludi utječu prirodni čimbenici poput botaničkog i geografskog podrijetla, sezonskih varijacija te pčelarskih praksi. Ishodi ispitivanja in vitro također ovise o načinu pripreme ekstrakata, vrsti otapala, korištenim mikrobnim sojevima i metodi određivanja antimikrobne aktivnosti. Dodatni izazov predstavlja ograničena bioraspoloživost bioaktivnih spojeva, uvjetovana vanjskim slojem peludi otpornim na razgradnju, nazvanim eksina. Stijenka se može djelomično razgraditi postupcima prerade koji ju razbijaju te time poboljšavaju nutritivna i funkcionalna svojstva peludi. Ovaj revijalni prikaz pruža sveobuhvatan pregled objavljenih istraživanja o antimikrobnoj aktivnosti monoflorne pčelinje peludi. Sažima najčešće istraživane biljne vrste i bakterijske sojeve, ističući one vrste peludi koje imaju najbolji antimikrobni učinak. Također, analizira metode prerade peludi, uspoređujući njihovu učinkovitost i promjene u antimikrobnoj aktivnosti peludi prije i nakon prerade. U radu su identificirane biljne vrste, otapala i metode kojima se postiže snažan antimikrobni učinak, te se naglašava njihov potencijal u daljnjoj standardizaciji parametara kakvoće pčelinje peludi
Ekstrakt kore bijele vrbe kao inhibitor korozije bakra
No full textThis study investigates white willow bark extract (WWBE) as a potential corrosion inhibitor for Cu-DHP in a 0.5MNaCl solution, using a non-destructive electrochemical methods, namely electrochemical frequency modulation (EFM), and electrochemical impedance spectroscopy (EIS). Electrolytes consisted of 0.5MNaCl solutions both with and without the addition of WWBE (0.1–0.5gl−1). The 0.5MNaCl solution containing 0.5gl−1 WWBE, both in the presence and absence of a copper plate, was analysed by ultraviolet-visible spectroscopy (UV-Vis). The experiments were conducted at room temperature. The EFM results indicated that WWBE functioned as a cathodic copper corrosion inhibitor, with the highest inhibition efficiency observed for the 0.5MNaCl solution containing 0.5gl−1 WWBE. The EIS results suggested the formation of a protective WWBE inhibitor film. The corrosion process was diffusion-controlled, both with and without the addition of WWBE. Both electrochemical methods demonstrated that WWBE adsorbed onto the copper surface in 0.5MNaCl solution via physisorption, following the Langmuir adsorption isotherm. The Gibbs free energy values of adsorption were similar for EFM and EIS. The UV-Vis results showed that immersion of copper in an electrolyte containing 0.5gl−1 WWBE for 24h led to a change in the absorbance maximum, indicating the formation of a copper–WWBE complex. Overall, the results indicate that WWBE is an effective inhibitor of copper corrosion in chloride conditions. Further research will focus on the identification of compounds and organometallic complexes in WWBE and their individual effects on the corrosion process.Ovo istraživanje ispituje ekstrakt kore bijele vrbe (WWBE) kao potencijalni inhibitor korozije Cu-DHP u otopini 0,5MNaCl, primjenom nedestruktivnih elektrokemijskih metoda, i to elektrokemijske frekvencijske modulacije (EFM) i elektrokemijske impedancijske spektroskopije (EIS). Elektroliti su se sastojali od otopina 0,5MNaCl, s i bez dodatka WWBE (0,1–0,5gl−1). Otopina 0,5MNaCl s dodatkom 0,5gl−1 WWBE, u prisutnosti i bez bakrene ploče, analizirana je ultraljubičasto-vidljivom spektroskopijom (UV-Vis). Eksperimenti su provedeni pri sobnoj temperaturi. Rezultati EFM metode pokazali su da WWBE djeluje kao katodni inhibitor korozije bakra, s najvećom učinkovitošću inhibicije u otopini 0,5MNaCl koja sadrži 0,5gl−1 WWBE. Rezultati EIS metode upućuju na stvaranje zaštitnog filma inhibitora WWBE. Proces korozije bio je kontroliran difuzijom, kako u prisutnosti tako i bez dodatka WWBE. Obje elektrokemijske metode pokazale su da se WWBE adsorbira na površinu bakra u otopini 0,5MNaCl fizisorpcijom, slijedeći Langmuirovu adsorpcijsku izotermu. Vrijednosti Gibbsove slobodne energije adsorpcije bile su slične za EFM i EIS metode. UV-VIS rezultati pokazali su da uranjanje bakra u elektrolit koji sadrži 0,5gl−1 WWBE tijekom 24h dovodi do promjene maksimuma apsorbancije, što ukazuje na stvaranje kompleksa bakar–WWBE. Sveukupno, rezultati pokazuju da je WWBE učinkovit inhibitor korozije bakra u kloridnim uvjetima. Daljnja istraživanja bit će usmjerena na identifikaciju spojeva i organometalnih kompleksa u WWBE te njihov pojedinačni utjecaj na proces korozije
Poboljšanje digitalnih vještina za održivi inženjering: pristupzasnovanna simulacijama u projektiranju procesa
No full textEngineering education is increasingly focused on developing both digital skills and sustainability awareness. To meet modern workforce demands, engineers must be proficient in using digital tools while designing environmentally responsible processes. The “Process Design” course at the Faculty of Chemistry and Technology integrates COCO (Cape-Open to Cape-Open) and ChemSep simulation software to enhance students’ digital competencies and deepen their understanding of sustainable chemical engineering. These free tools allow simulation of chemical processes, thermodynamic calculations, and optimisation of energy-efficient designs, enabling environmentally conscious decision-making. COCO, built on the CAPE-OPEN standard, includes modules for flowsheeting, unit operations, and reaction modelling, while ChemSep is used for simulating distillation columns. Together, they enable students to assess environmental impacts and design more sustainable processes. For this purpose, a survey was conducted among students to assess the software’s usability and its role in developing technical and soft skills such as creativity, critical thinking, and teamwork. The results showed that students recognised the value of the opportunity to simulate real-world processes, particularly in the context of sustainability. They found the tools accessible and effective in bridging theoretical knowledge with practical application. Students also emphasised the need for increased practical exercises and the incorporation of more complex simulation tasks. The integration of COCO and ChemSep proved beneficial in preparing students to address sustainability challenges through practical and digital competencies in process design, offering a free and accessible alternative to commercial simulation software, which is often limited by high costs and licensing constraints.Inženjersko obrazovanje sve više stavlja naglasak na razvoj digitalnih vještina i svijesti o održivosti. Da bi odgovorili na zahtjeve suvremenog tržišta rada, inženjeri moraju biti vješti u primjeni digitalnih alata te istodobno projektirati procese koji su okolišno prihvatljivi. Na kolegiju “Projektiranje procesa” na Kemijsko-tehnološkom fakultetu integrirani su simulacijski programi COCO (Cape-Open to Cape-Open) i ChemSep da bi se unaprijedile digitalne kompetencije studenata i produbilo razumijevanje održivog kemijskog inženjerstva. Ti besplatni programski alati omogućuju simulaciju kemijskih procesa, termodinamičke proračune i optimizaciju energetski učinkovitih rješenja, omogućujući donošenje odluka koje vode održivosti. COCO, temeljen na CAPE-OPEN standardu, uključuje module za izradu tijeka procesa, jedinične operacije i reakcijsko modeliranje, dok se ChemSep primjenjuje za simulaciju destilacijskih kolona. U kombinaciji omogućuju studentima procjenu utjecaja procesa na okoliš i projektiranje održivijih rješenja. U tu svrhu provedena je anketa među studentima radi procjene upotrebljivosti programskih alata i njihova utjecaja na razvoj tehničkih i mekih vještina poput kreativnosti, kritičkog mišljenja i timskog rada. Rezultati su pokazali da su studenti prepoznali vrijednost mogućnosti simuliranja procesa iz stvarnog svijeta, osobito u kontekstu održivosti. Smatraju programske alate pristupačnima i korisnima za povezivanje teorijskih znanja s praktičnom primjenom. Istaknuli su i potrebu za povećanjem broja praktičnih vježbi te uključivanje složenijih simulacijskih zadataka. Integracija COCO i ChemSep alata pokazala se korisnom u pripremi studenata za suočavanje s izazovima održivosti kroz razvoj praktičnih i digitalnih kompetencija u projektiranju procesa, nudeći besplatnu i dostupnu alternativu komercijalnim simulacijskim alatima, koji su često ograničeni visokim troškovima i licencijama
Isparljivi spojevi u ekstraktu komine vina sorte Merlot dobiveniekstrakcijom superkritičnim fluidom
No full textThe valorisation of grape pomace, a major by-product of winemaking, presents both an environmental challenge and a resource opportunity. This study investigates the volatile compounds present in Merlot grape pomace extracts obtained by supercritical fluid extraction (SFE) using carbon dioxide as solvent. Extracts from whole grape pomace, seeds and skins were analysed. Volatile compounds were collected by headspace solid-phase microextraction (HS-SPME) and analysed using gas chromatography-mass spectrometry (GC-MS). A total of 29 different volatile compounds were identified across the three extracts, of which 11 were common to all fractions. The volatile profiles were dominated by alcohols, followed by esters, while carboxylic acids, ketones, and terpenoids were also detected. Butane-2,3-diol was the major constituent in terms of chromatogram peak area, followed by 2-phenylethanol and various esters. Many of the identified volatile compounds are recognised for their sensory and bioactive properties, possessing proven antioxidant, antimicrobial, and anti-inflammatory effects, making them of interest to the food, cosmetics, and pharmaceutical industries. The results of this study confirm the effectiveness of supercritical fluid extraction in recovering a broad range of volatile compounds from Merlot grape pomace, underscoring its value as a sustainable feedstock rather than agricultural waste. However, due to the limited efficiency of supercritical fluid extraction in mobilising polar compounds when carbon dioxide is used as the sole solvent, additional extraction strategies are required for more comprehensive pomace valorisation. This research supports the potential integration of grape pomace extracts into bio-based industry applications, contributing to the transformation of waste into value-added products.Valorizacija komine grožđa, glavnog nusproizvoda proizvodnje vina, istodobno predstavlja izazov za okoliš i priliku za iskorištavanje resursa. Ovim istraživanjem ispituju se isparljivi spojevi ekstrakata komine grožđa sorte Merlot dobiveni ekstrakcijom superkritičnim fluidom koristeći se ugljikovim dioksidom kao otapalom. Analizirani su ekstrakti dobiveni od cijele komine, sjemenki iz komine i kožice iz komine grožđa. Isparljivi spojevi izdvojeni su mikroekstrakcijom vršnih para na krutoj fazi (HS-SPME), a potom analizirani plinskom kromatografijom spregnutom s masenom spektrometrijom (GC-MS). Ukupno je identificirano 29 isparljivih spojeva u trima ekstraktima, od kojih je 11 zajedničko svim uzorcima. U profilima isparljivih spojeva dominiraju alkoholi, zatim razni esteri te karboksilne kiseline, ketoni i terpenoidi. Najzastupljeniji spoj, kad je u pitanju površina ispod kromatografskog vrha, je butan-2,3-diol te nakon njega 2-feniletanol i različiti esteri. Mnogi od identificiranih spojeva poznati su po senzorskim i bioaktivnim svojstvima te posjeduju dokazane antioksidativne, antimikrobne i protuupalne učinke, od interesa u prehrambenoj, kozmetičkoj i farmaceutskoj industriji. Rezultati istraživanja potvrđuju učinkovitost superkritične ekstrakcije u izdvajanju širokog raspona isparljivih spojeva iz komine grožđa sorte Merlot, naglašavajući vrijednost tog materijala kao održive sirovine umjesto poljoprivrednog otpada. Uslijed slabijeg učinka superkritične ekstrakcije s isključivo ugljikovim dioksidom kao otapalom, kad je u pitanju mobilizacija polarnih spojeva, za potpuniju valorizaciju komine grožđa potrebno je primijeniti dodatne metode ekstrakcije. Ovo istraživanje podržava moguću integraciju ekstrakata komine grožđa u tzv. bio-based industrije, pretvarajući otpad u proizvode s dodanom vrijednosti
Clinical Application of Computational Psychiatry in Non-Pharmacological Therapeutic Interventions for Individuals with Depressive Disorders: a Systematic Review
No full textAim: This systematic review aimed to explore whether knowledge gained through computational psychiatry can be applied in non-pharmacological therapeutic interventions for individuals with depressive disorders and to identify which non-pharmacological approaches utilize this knowledge. Materials and Methods: This systematic review was conducted according to the PRISMA guidelines. PubMed and Scopus databases were searched for articles published in the last ten years using the terms “computational psychiatry” and “depression.” The study protocol was registered on the Open Science Framework. Results: Out of 777 articles, 15 were included in the review. The studies were divided into two groups: those investigating various brain stimulation techniques (direct current stimulation, electroconvulsive therapy, deep brain stimulation, and transcranial magnetic stimulation) and those examining behavioral and neurofeedback techniques. Findings indicate that computational psychiatry can optimize existing therapeutic approaches, including specific methodological aspects. Conclusion: This review indicates the potential for applying computational psychiatry methods in the non-pharmacological treatment of depressive disorders. These approaches enable the optimization of therapeutic strategies and the personalization of treatment to individual patients, enhancing the effectiveness of existing therapies
The Croatian chamber of economy quality marks “Croatian quality” and “Croatian creation” as instruments of the competitiveness of croatian products and services
No full textU dinamičnom poslovnom svijetu u kojem se poduzeća neprestano natječu za povjerenje potrošača, kvaliteta postaje ključni imperativ i direktno utječe na održivost, uspjeh i prepoznatljivost proizvoda kod potrošača. U prepoznavanju proizvoda i usluga koji zadovoljavaju visoke standarde kvalitete, važnu ulogu imaju znakovi kvalitete Hrvatske gospodarske komore (HGK) „Hrvatska kvaliteta“ i „Izvorno hrvatsko“. Znakovi kvalitete HGK nisu samo marketinški alati, već predstavljaju jamstvo da su proizvodi i usluge prošli neovisnu provjeru, ispunjavaju definirane kriterije izvrsnosti i pouzdana su potvrda kvalitete. Znakovi kvalitete HGK doprinose izgradnji povjerenja kod potrošača i promicanju hrvatske kvalitete na domaćem i međunarodnom tržištu te predstavljaju investiciju u budućnost hrvatskih gospodarskih subjekata i cjelokupnog hrvatskog gospodarstva. Cilj rada bio je analizirati utjecaj proizvoda i usluga koji su brendirani znakovima „Hrvatska kvaliteta“ i „Izvorno hrvatsko“ na njihovu konkurentnost i brendiranje na otvorenom tržištu. U radu je prikazan postupak dodjele znakova kvalitete HGK te opseg njihove uporabe. Metodologija rada temelji se na analizi rezultata empirijskog istraživanja koje je, na zahtjev HGK, provela neovisna specijalizirana agencija, uz primjenu metoda analize, sinteze, indukcije, dedukcije, deskripcije i ankete. Rezultati provedenog empirijskog istraživanja potvrdili su da znakovi kvalitete HGK značajno jačaju konkurentnost, brendiranje i prepoznatljivost hrvatskih proizvoda te zahtijevaju snažniju promociju kao dugoročnu investiciju.In a dynamic business environment in which organizations continuously compete for consumer trust, quality becomes a key imperative and directly affects sustainability, success, product recognition among consumers. In identifying products and services that meet high quality standards, the quality marks of the Croatian Chamber of Economy (CCE), Croatian Quality and Croatian Creation, play an important role. CCE quality marks are not merely marketing tools, they represent a guarantee that products and services have undergone independent verification, meet defined excellence criteria, and provide reliable confirmation of quality. These quality marks contribute to building consumer trust and promoting Croatian quality in both domestic and international markets, representing an investment in the future of Croatian businesses and the national economy as a whole. The aim of this paper was to analyze the impact of products and services branded with the Croatian Quality and Croatian Creation quality marks on their competitiveness and branding in an open market. The paper presents the procedure for awarding CCE quality marks and the scope of their use. The methodology is based on an analysis of the results of conducted empirical study, at the request of the CCE, by an independent specialized organization, using the methods of analysis, synthesis, induction, deduction, description, and survey research. The results of the empirical study confirmed that CCE quality marks significantly enhance the competitiveness, branding, and recognition of Croatian products and require stronger promotion as a long-term investment
Evaluation of Digital Development Indexes Using MEREC and Hybrid MCDM Methods
No full textThe use of relevant and structured instruments for measuring digital development is essential for policy-making in digitalization. The aim of the research is to compare structural adequacy of the global digital development indexes by means of multicriteria decision-making (MCDM). Theoretical contribution is to develop an evaluation framework and propose a novel methodological integration. Nine criteria were used to quantify six indexes: the Network Readiness Index (NRI), the E-Government Development Index (EGDI), the Digital Economy and Society Index (DESI), the ICT Development Index (IDI), the IMD World Digital Competitiveness Ranking (IMD) and the Global Digital Index (GDI). The criteria's objective weights were evaluated using the Method based on the Removal Effects of Criteria (MEREC) and the weights alterations effect was considered using the Shannon entropy method. The final prioritization was consolidated using five MCDMs scores: Combined Compromise Solution (CoCoSo), Measurement Alternatives and Ranking according to the Compromise Solution (MARCOS), Additive Ratio Assessment (ARAS), COmbinative Distance-based ASsessment (CODAS) and Evaluation based on Distance from Average Solution (EDAS). Practical contribution and originality are presented by proposing first time evaluation framework of digital development indexes based on a recently proposed MEREC and selecting the most appropriate index (NRI) in a neutral MCDM context
EMOCIONALNA INTELIGENCIJA MENADŽERA I POTENCIJAL RAZVOJA KARIJERE ZAPOSLENIKA: DISKRIMINANTNA ANALIZA
No full textThis study examines the extent to which managers’ emotional intelligence, operationalized through empathic behavioural patterns, differentiates employees with respect to their career development potential. Data were collected through two online questionnaires administered to managers (n = 97) and employees (n = 480) from 37 organizations in Croatia, with hierarchically linked samples (employees evaluated their immediate supervisors). Managers’ emotional intelligence was measured through four empathic constructs, while employees’ career development potential was assessed using five constructs: career decision determination, career planning capability, motivation for career realization, career-related beliefs, and career-related competencies and professional values. Linear discriminant analysis was applied to 24 employee subgroups. The results indicate that the set of career development variables clearly differentiates the groups: in the group with non-empathetic managers, three subgroups were reclassified into the group with emotionally intelligent managers, while no reclassifications occurred in the opposite direction. The findings confirm the importance of managers’ emotional intelligence in shaping employees’ developmental resources.Ovaj rad istražuje u kojoj mjeri emocionalna inteligencija menadžera, operacionalizirana na temelju empatičnih obrazaca ponašanja, razlikuje zaposlenike s obzirom na njihov karijerni razvojni potencijal. Podaci su prikupljeni s pomoću dvaju online upitnika: menadžeri (n = 97) i zaposlenici (n = 480) iz 37 organizacija u Hrvatskoj, pri čemu su uzorci hijerarhijski povezani (zaposlenici su procjenjivali odnos prema svom neposrednom nadređenom). Emocionalna inteligencija menadžera mjerena je na temelju četiriju empatičnih konstrukata, a karijerni razvojni potencijal zaposlenika na temelju pet konstrukata: odlučnost, planiranje, motivaciju, karijerna uvjerenja te kompetencije i profesionalne vrijednosti. Primijenjena je linearna diskriminantna analiza na 24 podskupine zaposlenika. Rezultati pokazuju da skup varijabli karijernog potencijala jasno razlikuje skupine: u skupini s neempatičnim menadžerima tri su podskupine reklasificirane u skupinu s emocionalno inteligentnim menadžerima, dok u suprotnom smjeru nema reklasifikacija. Nalazi potvrđuju važnost emocionalne inteligencije menadžera u oblikovanju razvojnih resursa zaposlenika