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Imipramine solubility-pH profiles: self-aggregation vs. common-ion effect
No full textBackground and Purpose: The pH-dependent solubility of imipramine (Imp), a tricyclic antidepressant, was investigated in phosphate buffers and chloride-containing aqueous media using the pH-Ramp shake-flask method. It was reported that aggregation of Imp in acidic media and its partial degradation in alkaline media complicate the determination of its solubility. This was further investigated with modified methods. Experimental Approach: For Imp solubility studies, the computer program pDISOL-X was used to design experiments, process data, and refine the equilibrium constants. Isolated solid precipitates under various conditions were characterized using thermogravimetric analysis, differential scanning calorimetry, powder X-ray diffraction, and elemental analysis. The critical micelle concentration (CMC) of ImpHCl was determined in 0.10 M NaH2PO4 and in 0.15 M NaCl by conductometric titrations. Key Results: Detailed analysis of Imp pH-solubility profiles reveal complex equilibria in the aqueous phase and various solid-phase transformations as well. Intrinsic solubility of Imp, solubility products of Imp hydrochloride and Imp phosphate salts, and aggregation constants (trimer, heptamer, and cationic complex with phosphate ions) were determined. Solid state characterization results are in accordance with pDISOL-X analysis. Conclusion: These findings, along with our previous solubility studies of desipramine and nortriptyline, suggest that even subtle structural variations can lead to significant differences in the aqueous media behavior of tricyclic antidepressants. This type of information can be valuable in the early stages of drug discovery, in formulation optimization experiments, as well as in in vitro and in vivo studies
Injectable hydrogels for bone regeneration: mechanical reinforcement strategies using nanoparticles and nanofibers
No full textBackground and Purpose: The growing demand for bone regeneration following severe injuries highlights the importance of scaffolds in bone tissue engineering (BTE). Injectable hydrogels have emerged as promising candidates because their properties closely mimic the native extracellular matrix (ECM). However, their limited mechanical strength and structural instability restrict their practical application. Approach: This review summarizes recent strategies for reinforcing in situ-forming injectable hydrogels to improve their mechanical performance for bone regeneration. Particular emphasis is placed on nanomaterial-based strategies, including the incorporation of nanoparticles and nanofibers, and their ability to enhance the physical properties of polymeric networks. Key Results: Evidence from recent studies demonstrates that reinforcing hydrogels with nano-scaled materials creates interconnected networks that improve load-bearing capacity, stability, and resistance to deformation. These reinforced systems retain the inherent advantages of injectable hydrogels-biocompatibility, biodegradability, permeability to oxygen and nutrients, and drug delivery capability-while addressing their mechanical shortcomings. Conclusion: Nanomaterial-based reinforcement offers a versatile approach to overcoming the limitations of injectable hydrogels in BTE. By providing improved structural integrity alongside biological functionality, these advanced systems broaden the potential of injectable hydrogels for clinical translation. Future work should focus on optimizing reinforcement strategies to balance mechanical enhancement with safety, manufacturability, and regulatory considerations
Aktualnosti iz projekta “Znanje+Kreativnost = STEM Inspiracija”: Kalendar događanja travanj 2026. (“Znanje+Kreativnost = STEM Inspiracija”)
No full textOsvrti: Projekt “A comprehensive AI powered early warning system for digital management of water supply security, resilience, and sustainability (AquaGuardian)” osigurao financiranje u okviru Challenge programa (DIGIT.2.1.02.)
No full textHigh-mortality outbreak of Yersinia pseudotuberculosis infection in a guinea pig herd: a case report
No full textYersinia pseudotuberculosis caused a fulminant outbreak in a Croatian breeding colony of 84 guinea pigs, in which 80 animals (95%) died within 72 hours after abrupt food refusal and marked lethargy, without diarrhoea. Seven freshly dead animals were examined. At necropsy, 2–5 mm, white-yellow nodules were found distributed in the liver, spleen, lungs, mesenteric lymph nodes and partly also in the small intestine. Aerobic culture of these organs on Columbia blood agar (28°C, 24–48 h) revealed pure growth of Y. pseudotuberculosis. Histology showed well demarcated necro-pyogranulomatous lesions with central bacterial colonies, margins of neutrophils and a peripheral coat of macrophages and few lymphocytes. Immunohistochemistry confirmed abundant lysozyme-positive macrophages and few CD3-positive T and CD79α-positive B cells, indicating a predominantly innate response. This case report emphasises the extreme lethality and rapid progression of guinea pig yersiniosis and highlights its zoonotic potential
OTPORNOST NA KOMPROMITIRANJE POSLOVNE E-POŠTE: STUDIJA SLUČAJA KORPORACIJE
No full textThis paper presents a case study of a Business Email Compromise (BEC) attack and its impact on a company’s operations. The research employed qualitative methods, including semi-structured interviews with corporate stakeholders and a literature review, to examine the state of organizational cybersecurity and identify lessons learned from cyber fraud incidents. The findings show that regular cybersecurity training, external email tagging, and robust internal communication protocols significantly reduce fraud risks. In particular, verification procedures for financial transactions and changes to banking details were identified as critical safeguards. The study highlights that cybersecurity is not merely a technical issue but a strategic business concern requiring a holistic, organization-wide approach. Human factor plays a pivotal role, and organizations must combine technical controls with employee awareness and management oversight. Practical recommendations are provided to enhance resilience against BEC attacks, especially in international contexts where trust between business partners can be exploited.Ovaj rad predstavlja studiju slučaja napada kompromitiranjem poslovne e-pošte (BEC) i njegov utjecaj na poslovanje tvrtke. U istraživanju korištene su kvalitativne metode, uključujući polustrukturirane intervjue s korporativnim dionicima i pregled literature, kako bi se ispitalo stanje organizacijske kibernetičke sigurnosti i identificirale pouke iz incidenata kibernetičkih prijevara. Nalazi pokazuju da redovita obuka o kibernetičkoj sigurnosti, vanjsko označavanje e-pošte i robusni interni komunikacijski protokoli značajno smanjuju rizike od prijevare. Postupci provjere financijskih transakcija i promjene bankovnih podataka prepoznati su kao ključne zaštitne mjere. U istraživanju se naglašava da kibernetička sigurnost nije samo tehničko pitanje, već strateška poslovna briga koja zahtijeva holistički pristup na razini cijele organizacije. Ljudski faktor igra ključnu ulogu, a organizacije moraju kombinirati tehničke kontrole s osviještenošću zaposlenika i nadzorom uprave. Daju se praktične preporuke za poboljšanje otpornosti na BEC napade, posebno u međunarodnim kontekstima, gdje se povjerenje između poslovnih partnera može zloupotrijebiti
Influence of Residual Temperature on Microstructure Evaluation of Cast-Rolled 6061 Sheet
No full textIn this paper, a rolling process at residual temperatures is proposed. Special attention is given to the effects of different process parameters (e.g., residual rolling temperature and residual strain rate) on the microstructural evolution of cast-rolled 6061 aluminum alloy sheet. It was found that excellent grain refinement and a uniform structure (i.e., an average shrinkage cavity size of 13.71 μm and minimal grain size) were achieved at a residual rolling temperature of 390 ℃. With increasing rolling reduction, the grains in the core became more refined, and the grain size difference between the surface and central layers was reduced. Furthermore, the α(AlFeSi) phase was fragmented and dispersed with increasing pressure
ODREDNICE I TRENDOVI SIROMAŠTVA STANOVNIŠTVA U SKANDINAVSKIM I BALTIČKIM ZEMLJAMA
No full textThe "Sustainable Europe by 2030" initiative aligns with the United Nations' Sustainable Development Goals (SDGs) and focuses on various aspects of poverty, including income poverty, social deprivation, and labour market participation. Research on poverty trends in countries with average or above-average incomes is limited, but recent socio-economic changes and the ineffectiveness of anti-poverty programs in these regions highlight the need for such studies. This research employs regression analysis models using panel data, specifically the Ordinary Least Squares and Fixed Effects Models, to estimate the marginal effects of changes in population poverty and the contributing factors. The study found that despite the faster economic growth in the Baltic countries, a decrease in long-term unemployment, and an increasing number of individuals with higher education, these factors did not lead to lower poverty levels than those in Scandinavian countries. Effective poverty reduction in the latter group can be attributed to health and social security policies aimed at reducing poverty, as well as lower income inequality.Inicijativa „Održiva Europa do 2030.“ usklađena je s ciljevima održivog razvoja Ujedinjenih naroda (SDG) i usredotočena je na različite aspekte siromaštva, uključujući siromaštvo zbog nedostatka prihoda, socijalnu deprivaciju i sudjelovanje na tržištu rada. Istraživanja trendova siromaštva u zemljama s prosječnim ili iznadprosječnim prihodima ograničena su, ali nedavne socioekonomske promjene i neučinkovitost programa protiv siromaštva u tim regijama naglašavaju potrebu za njihovom provedbom. Ovo istraživanje koristi se regresijskom analizom panel podataka, konkretno modelima običnih najmanjih kvadrata i modelima fiksnih efekata, kako bi procijenilo granične učinke promjena u siromaštvu stanovništva te čimbenike koji na njega utječu. Istraživanje je pokazalo da, unatoč bržem gospodarskom rastu u baltičkim zemljama, smanjenju dugotrajne nezaposlenosti i rastu udjela visokoobrazovanih osoba, ti čimbenici nisu rezultirali nižim razinama siromaštva u usporedbi sa skandinavskim zemljama. Učinkovito smanjenje siromaštva u potonjoj skupini može se pripisati zdravstvenim i socijalnim politikama usmjerenima na smanjenje siromaštva, kao i manjoj nejednakosti u prihodima
ISTRAŽIVANJE POVEZANOSTI IZMEĐU EMISIJA, GOSPODARSKOG RASTA I ZAPOSLENOSTI: DOKAZI IZ AZERBAJDŽANA
No full textThis paper explores the dynamic relationship between Azerbaijan’s green economy and employment by analyzing GDP per capita, CO₂ emissions, and employment rates using the Toda-Yamamoto causality method on annual data from 1990 to 2023. The empirical results reveal two key findings: (1) a statistically significant bidirectional causality between the employment rate and GDP per capita, indicating mutual reinforcement between economic growth and labor market performance; and (2) a statistically significant unidirectional causality from CO₂ emissions per capita to employment at the 1% significance level, underscoring the role of environmental factors in shaping employment dynamics. Our findings reveal a unidirectional positive relationship between CO₂ emissions and employment, suggesting that increased emissions are associated with rising employment levels. This paper contributes by providing the first time-series evidence from Azerbaijan on the causal links between CO₂ emissions, GDP per capita, and employment, using the Toda-Yamamoto approach.Ovaj rad istražuje dinamički odnos između zelenoga gospodarstva Azerbajdžana i zaposlenosti analizirajući BDP po glavi stanovnika, emisije CO₂ i stope zaposlenosti primjenom Toda-Yamamotove metode kauzalnosti na godišnjim podacima od 1990. do 2023. godine. Empirijski rezultati otkrivaju dva ključna nalaza: (1) statistički značajnu dvosmjernu kauzalnost između stope zaposlenosti i BDP-a po stanovniku, što ukazuje na uzajamni utjecaj gospodarskog rasta i učinka tržišta rada; (2) statistički značajnu jednosmjernu kauzalnost između emisija CO₂ po stanovniku i zaposlenosti na razini značajnosti od 1%, što naglašava ulogu okolišnih čimbenika u oblikovanju dinamike zaposlenosti. Naši nalazi otkrivaju jednosmjerni pozitivan odnos između emisija CO₂ i zaposlenosti, što sugerira da su povećane emisije povezane s rastućom razinom zaposlenosti. Doprinos ovog rada jest pružanje prvih vremenskih serija dokaza iz Azerbajdžana o uzročno-posljedičnim vezama između emisija CO₂, BDP-a po glavi stanovnika i zaposlenosti koristeći se Toda-Yamamotovim pristupom
Croatian Philosopher Đuro Gračanin on Bergson’s Conception of Christianity
No full textHrvatski filozof, teolog apologet i svećenik Đuro Gračanin (1899.–1973.) zadnjih
dvadesetak godina sve se više tematizira na području istraživanja hrvatskoga filozofskoga
i teološkoga nasljeđa. Doktorirao je 1935. na Bogoslovnom fakultetu
u Zagrebu tezom Moderni filozof branitelj kršćanstva?: Omogućuju li Bergsonove
koncepcije kršćanstva ispravno poimanje naravnog i nadnaravnog reda? U
prvom poglavlju članka iznesena je kratka Gračaninova biografija. U drugom
poglavlju tematiziran je Gračaninov doktorski rad s ciljem pronalaska njegovih
argumenata za i protiv pojedinih Bergsonovih filozofskih stajališta. U trećem
poglavlju članka taksativno je nabrojana percepcija Bergsonove filozofske misli
kod nas.Over the past twenty years the Croatian philosopher, theologian, apologist and priest
Đuro Gračanin (1899–1973) has been the subject of an increasing number of studies
in the field of Croatian philosophical and theological heritage. The initial chapter of
the paper presents a concise biographical account of Gračanin, providing an overview
of his life and work. Gračanin was born in 1899 in Gacko, and he pursued his studies in Paris and Zagreb. He was awarded his doctoral degree on the strength of
his studies in both Paris and Zagreb. At the Faculty of Theology in Zagreb, he was
awarded his doctorate for a thesis entitled ‘Modern Philosopher Defender of Christianity?’.
It deals with the question: Does Bergson’s conceptualisation of Christianity
facilitate an accurate comprehension of the natural and supernatural realms?
He held the position of Professor of Theology at the Faculty of Theology in Zagreb
for a considerable period of time, in addition to which he also served as Dean. He
passed away in Zagreb in 1973. The second chapter of the paper analyses Gračanin’s
doctoral thesis with the objective of identifying the arguments he presents in favour
of and in opposition to specific philosophical positions put forth by Bergson. On
the one hand, Gračanin acknowledges Bergson’s contributions to the affirmation of
Christianity and Christian teaching. Nevertheless, he also identifies certain deficiencies
in the philosophy being examined. These include an erroneous understanding of
God (pantheism), an inability to distinguish between nature and the supernatural,
and an insufficient grasp of the role of grace in the lives of Christian mystics. The
third chapter of the work presents a previously unnoticed perception of Bergson’s
philosophical thought in our country Croatia, as it relates to research that has been
previously published. It can be concluded that Gračanin’s doctoral thesis on Bergson
did not contribute to the advancement of Bergson’s philosophy in our country.
Nevertheless, recent developments have demonstrated that Gračanin’s philosophical
thought is increasingly being recognized and examined which indicates a growing
interest in his work