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Filtering Microstrip Patch Antenna Design Using Coupling Matrix Approach for ISM Applications
No full textThis paper presents a novel design approach for a filtering microstrip patch antenna inspired by a bandpass filter (BPF). It is based on the coupling matrix approach, where the magnitudes of the matrix elements are utilized to extract the physical dimensions. Two rectangular microstrip patch resonators (RMPRs) are directly coupled via an air-gap to realize a second-order BPF and a filtering microstrip patch antenna. For the BPF, a 50-Ω microstrip feedline is employed at the input/output ports and extended into the center of the RMPRs to ensure strong impedance matching within the passband of interest. For the filtering antenna, the output feedline port is removed, and the second RMPR is modified to obtain the required radiation quality factor and provide radiation within the passband frequency range. To validate the proposed approach, both designs are fabricated and experimentally tested, showing excellent agreement with the simulation results. The measured 10-dB fractional bandwidth (FBW), passband peak gain, and total efficiency are 4.05%, 6.0 dBi, and 74.0%, respectively. These results demonstrate that the proposed designs offer a compact size, high gain, and high efficiency, making them promising candidates for ISM band applications
SLOVNICA HEBREJSKOG JEZIKA BY JURAJ DOČKAL IN THE CONTEXT OF EUROPEAN HEBREW PHILOLOGICAL MOVEMENTS IN THE 19TH CENTURY
No full textSlovnica hebrejskog jezika Jurja Dočkala objavljena je 1893. godine. Temeljila se na njemačkim udžbenicima i gramatikama koje su se tada smatrale najboljima. Njezina vrijednost leži u činjenici da je napisana na hrvatskom jeziku u vrijeme procvata hebrejskog jezikoslovlja u zapadnoj Europi. Slovnica se sastoji od četiri dijela. Prvi dio bavi se glasovima hebrejskog jezika i njihovim znakovima, drugi dio raspravlja o promjenama glasova u tvorbi riječi i oblika, treći dio predočava oblike zamjenica, glagola, imena i čestica, a četvrti dio obuhvaća osnovna pravila sintakse hebrejskog jezika. Cilj članka je kontekstualizirati Slovnicu hebrejskog jezika unutar europskih, posebice njemačkih, hebreističkih strujanja 19. stoljeća te istaknuti njezino značenje kao pionirskog doprinosa hrvatskoj hebreistici, bez vrednovanja sadržaja i detaljne razrade gramatike.Slovnica hebrejskog jezika (The Grammar of the Hebrew Language) by Juraj Dočkala was published in 1893 and was based on German textbooks and grammars that were considered the best at the time. Its value lies in the fact that it was written in the Croatian language during the peak of Hebrew linguistics in Western Europe. The grammar consists of four parts. The first part deals with the sounds of the Hebrew language and their signs, the second part discusses changes in sounds in word formation and forms, the third part presents the forms of pronouns, verbs, nouns, and particles, while the fourth part covers the basic rules of Hebrew syntax. The aim of this article is to contextualize the Hebrew Grammar within the European, particularly German, Hebrew scholarly movements of the 19th century and to highlight its significance as a pioneering contribution to Croatian Hebraistics, without evaluating the content or providing a detailed analysis of the grammar
JEAN GERSON AND THE FORMATION OF THE DOCTRINE OF ST. JOSEPH: FROM THE PROTECTOR OF NAZARETH TO A MODEL OF CHURCH RENEWAL
No full textIako prisutan u tradiciji, lik svetog Josipa ostaje doktrinarno nedorečen sve do 15. stoljeća i zahvata Jeana Gersona. Cilj je ovoga rada istražiti Gersonovnauk o sv. Josipu kao sustavan projekt, polazeći od hipoteze da on koristi Josipov autoritet kao političko - teološki alat za obnovu Crkve. Gerson napušta prikaz Josipa kao pasivnog svjedoka i uvodi ga u središte ekleziologije kroz trostruki koncept očinstva (pater legalis, moralis, socialis) i doktrinu o savršenoj čistoći (purissimus). Time Josip postaje zemaljska slika božanskog autoriteta, a njegova zemaljska zaštita Svete obitelji teološki temelj za nebeski patronat nad cijelom Crkvom. Ova teološka konstrukcija doseže vrhunac tijekom Velikog zapadnog raskola, kada Gerson u spjevu Josephina zaziva Josipa kao „stup“ (columen) koji drži „umorne ruševine“ Crkve. Za Gersona, Josip je idealni Oeconomus (upravitelj) čija vlast nije apsolutističko vlasništvo, već ponizna skrb. Ta vizija izravno je podupirala koncilijarnu ideju Sabora u Konstanzi: Crkva, poput Svete obitelji, treba upravitelja koji teži jedinstvu, a ne dominaciji. Provodeći „liturgijsku diplomaciju“ kroz uvođenje Josipova blagdana, Gerson je težio postizanju „svetog sklada“ (concordia sacra) među zavađenim frakcijama. Gersonov doprinos leži u transformaciji nauka o sv. Josipu iz privatne pobožnosti u javnu ekleziološku doktrinu. On postavlja Josipa kao jamca jedinstva, nudeći njegov model služenja kao „političku medicinu“ za krizu papinstva. Time Gerson ne samo da utemeljuje moderni nauk o svetom Josipu, već ga trajno definira kao nebeski oslonac institucionalne i moralne obnove Crkve.This study explores the christocentric and ecclesiological foundations of Saint Joseph’s role in the theological corpus of Jean Gerson. Far from being a mere object of late medieval piety, Gerson’s Josephology functions as a sophisticated theological system designed to address the institutional and moral crisis of the Great Western Schism. By redefining fatherhood through the categories of legal, moral, and social authority (pater legalis, moralis, et socialis), Gerson elevates Joseph from a marginal biblical figure to a central pillar of ecclesiastical reform. The research highlights Gerson’s innovative conceptualization of Joseph as the Oeconomus (Steward) and Columen (Pillar) of the Church, providing a conciliarist alternative to papal absolutism. Through his monumental epic Josephina and his efforts at the Council of Constance, Gerson utilized Josephology as a form of “political medicine” and liturgical diplomacy, aiming to restore the concordia sacra and ensure the unity of the Mystical Body of Christ. Ultimately, Gerson’s work laid the groundwork for modern Josephology, transforming private devotion into a public theological doctrine essential for the understanding of church governance, service, and universal patronage
ANTUN GUSTAV MATOŠ BETWEEN ZAGREB AND BELGRADE: A CULTURAL PERSPECTIVE
No full textU radu se u kulturološkoj perspektivi obrađuje koncept grada/gradova Zagreba i Beograda u književnom opusu Antuna Gustava Matoša (1873.-1914.). Matoš se shvaća kao interkulturalist u svim vidovima svojega djelovanja; neprestano je poticao i izazivao interkulturna pitanja između Srba i Hrvata, uključujući pitanje identiteta, razlika i mogućnosti dijaloga. U temeljnom odnosu interkulturalizma, Matoš je predstavljao, zastupao i tumačio kulture – hrvatsku i srpsku – što je interkulturna komunikacija prvoga reda. Iz susreta i života u Beogradu, Parizu i Zagrebu nastaju njegove najoriginalnije misli koje djeluju poticajno u pogledu razmatranja razlika i sličnosti etničke, kulturne, religiozne, duhovne naravi, kao i o raspravi o stereotipovima i predrasuda. Matoš je u Beogradu boravio gotovo osam godina koje su ostavile snažan utjecaj na njegovu misao i djelo, osobito na zamisao političkoga Balkana kojem se u konačnici snažno protivio. U Matoševom diskursu posebno mjesto pripada kulturološkim slikama i kulturnim stereotipima Zagreba, kojem posvećuje posebnu pozornost upravo u kontrastnom odnosu prema Beogradu. Tema grada Zagreba/Beograda u interkulturnoj perspektivi pojavljuje se kao prostor i kulturna činjenica uvijek povezana s tkivom nacionalnog identiteta i svih pitanja koje iz njega proizlaze. Percepcija identiteta u sklopu „totalnog fenomena“ grada pobuđuje najveći interes, budući da se dodiri kultura događaju upravo u urbanim kontekstima, te unatoč različitostima i predrasudama, mogu biti poticaj za bolje razumijevanje između ljudi i njihovih nasljeđa. Najzad, tema interkulturalnosti u perspektivi „konstrukcije drugoga“ i „naracije o sebi“, omogućuje stvaranje novih individualnih i društvenih vrijednosti, odnosno, stvara pretpostavke za novu kvalitetu dijaloga identiteta koji će biti iščitani duž analitičkih cjelina u ovom radu.This paper examines, from a cultural perspective, the concept of the cities of Zagreb and Belgrade in the literary oeuvre of Antun Gustav Matoš (1873–1914). Matoš is understood as an interculturalist in all aspects of his work; he constantly encouraged and provoked intercultural questions between Serbs and Croats, including issues of identity, differences and the possibility of dialogue. In the fundamental relationship of interculturalism, Matoš represented, promoted and interpreted cultures – Croatian and Serbian – which constitutes intercultural communication of the first order. From his encounters and life in Belgrade, Paris and Zagreb, his most original thoughts emerged, which serve as a stimulus for considering differences and similarities of an ethnic, cultural, religious and spiritual nature, as well as for the debate on stereotypes and prejudice. Matoš lived in Belgrade for almost eight years, a period which had a profound influence on his thought and work, particularly on his imagination of a political Balkan region which he ultimately strongly opposed. In Matoš’s discourse, a special place is given to the cultural images and stereotypes of Zagreb, to which he devotes particular attention in contrast to Belgrade. The theme of Zagreb/Belgrade in an intercultural perspective emerges as a space and cultural fact, always connected to the fabric of national identity and all the questions that arise from it. The perception of identity within the “total phenomenon” of the city is of the greatest interest, as encounters between cultures occur precisely in urban contexts and, despite differences and prejudices, can be a catalyst for a better understanding between people and their heritage. Finally, the theme of interculturality, in the perspective of the “construction of the other” and the “narrative of the self”, enables the creation of new individual and social values; in other words, it creates the prerequisites for a new quality of identity dialogue, which will be examined throughout the analytical sections of this paper
Liposome-mediated gene delivery: A comprehensive review of biophysical parameters, lipid composition and targeting strategies
No full textBackground and purpose: Gene therapy has emerged as a transformative strategy for treating genetic and acquired disorders, but its clinical success relies heavily on the development of safe, efficient, and target-specific delivery vectors. Experimental approach: The paper systematically analysed published evidence on liposome composition, physicochemical behaviour, targeting strategies, and their applications in delivering diverse nucleic acids, with emphasis on the structure-function relationships of lipid components and the impact of biophysical parameters on transfection efficiency. Key results: Current findings demonstrate that the molecular architecture of cationic, neutral, and anionic lipids, particularly variations in head groups, linkers, and hydrophobic tails, strongly dictates liposome stability, cellular uptake, and cargo release. Biophysical attributes such as vesicle size, zeta potential, membrane fluidity, fusion capacity, and PEGylation were identified as major determinants of in vivo fate. Active targeting through ligands, including antibodies, peptides, folate, and aptamers, enhances cell-specific delivery, while combinatorial approaches with physical enhancement techniques such as sonoporation and electroporation further improve nucleic acid transport. Conclusion: By integrating structural, functional, and application-based insights, this review highlights key design principles for optimizing next-generation liposomal vectors, although challenges remain in achieving consistent in vivo performance and clinical translation. The work advances the field by offering a unified framework to guide rational engineering of liposomal platforms for gene therapy
Intranasal carvacrol nanoemulsion: Stroke imaging and neuroprotective study
No full textBackground and purpose: Cerebral ischemia causes neuronal damage due to restricted blood flow and presents significant challenges for brain-targeted drug delivery because of the blood-brain barrier. The purpose of this study is to formulate and evaluate an intranasal oil-in-water nanoemulsion of carvacrol, a neuroprotective agent, for direct nose-to-brain delivery in treating cerebral ischemia. Experimental approach: Nanoemulsions were developed using high-pressure homogenization and optimized by adjusting surfactant mixture ratios and homogenization cycles. Characterization included droplet size
Variance components for weight and type traits in a multiracial population of meat sheep in eastern Antioquia
No full textThe objective of genetic evaluation is to provide a tool to identify and select genetically superior animals that transmit desirable traits to their offspring, improving flock productivity over generations. This study aimed to evaluate genetic and phenotypic parameters for weight and type traits in a multiracial meat sheep population in eastern Antioquia, using Bayesian inference analysis. The study was conducted at two farms: “Ovinos de la Sierra” in La Ceja del Tambo, and “El Charrascal” in Copacabana, Antioquia, Colombia. Animals from various racial groups were evaluated, focusing on productive traits, namely birth weight (BW) and adjusted weaning weight at 90 days (AW90), together with twelve phenotypic traits. A single-trait animal model was applied, incorporating the fixed effects of breed type, calving type, sex, and live weight. Variance components and genetic parameters and expected breeding values were estimated. The mean (± standard deviation) for BW and AW90 were 3.655 ± 0.806 kg and 19.610 ± 5.181 kg, respectively. Direct and maternal heritability estimates for BW were 0.6734 and 0.2963, and for AW90 were 0.9323 and 0.0670. Among phenotypic traits, thoracic perimeter showed the highest heritability, followed by rump length, while the lowest heritability estimates were for withers width and rump width. All estimates were convergent, except maternal and phenotypic estimates for BW. Proper data recording is essential for evaluating genetic and phenotypic parameters, and Bayesian analysis provides reliable variability through posterior distributions, supporting the grouping of animals by age and production group for uniform data
Detailed dynamic thermal-hydraulic network model: Application to liquid-immersed power transformers – Part I
Get PDFThe paper presents the concept of temperature calculation in oil-immersed power transformers based on a detailed Thermal-Hydraulic Network Model (THNM). The THNM is deeply rooted in physics, incorporating detailed construction, material properties, and cooling equipment characteristics. Software tools based on a steady-state version of detailed THNM are becoming prevalent as design tools. However, a detailed dynamic THNM has not yet reached that level of technology readiness. Its practical application lies in operational decision-making, grid planning, and investment planning, as well as monitoring, where the detailed dynamic THNM can be used to simulate transformer thermal behavior during grid operation under variable loading conditions
Spurious correlations…
Get PDFThis article explores how convincing correlations can be misleading, especially when amplified by modern AI tools that confidently present weak or false causal links. Using examples from outside and inside the power sector, it highlights why correlation should never be mistaken for understanding
Towards Decarbonization of the Maritime Transport Sector: A Review of Hydrogen as an Alternative Marine Fuel
Get PDFThis review examines the current landscape of hydrogen production technologies, including thermochemical, electrochemical, and biological methods, highlighting their efficiencies, feedstock requirements, and environmental implications. Furthermore, the paper explores the challenges and advancements in hydrogen storage technologies, primarily on compressed gas, liquefied hydrogen, and solid-state storage. Hydrogen technology across industries, from transportation, to grid energy storage and industrial processes are discussed, with a focus on maritime sector applications, showcasing hydrogen’s versatility and decarbonization potential. Despite its promise, large-scale hydrogen adoption is constrained by high costs, infrastructure limitations, and energy efficiency concerns. This review aims to provide a foundational understanding for researchers and policymakers to support the advancement of hydrogen as a key component in future energy systems