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Cellulose-based nanomaterials are fascinating renewable biosystems, yet low thermal conductivity and dielectric permittivity often limit their potential applications in flexible electronics. We report dielectric properties of composite films prepared by vacuum filtration or solvent casting method from the native (CNF) or carboxylated (TCNF) cellulose nanofibrils and high electrically and thermally conductive 2D titanium carbide (Ti3C2Tx) MXenes. Measurements over broad frequency and temperature ranges revealed the influence of preparation method and type of nanofibrils matrix on the overall dielectric response, as well as a notable impact of absorbed water, particularly on the cellulose’s secondary β and γ relaxations. A detailed investigation of material with the lowest amount of impurities, vacuum-filtered MXene/CNF composites, confirmed that the dielectric response follows the predictions of the percolation theory. The resulting strong enhancement of the dielectric permittivity on increasing MXene content demonstrates the potential of developed composites for applications in eco-friendly dielectric and piezoelectric devices.

Supported lipid bilayers (SLBs) are low-complexity biomimetic membranes, serving as popular experimental platforms to study membrane organization and lipid transfer, membrane uptake of nanoparticles and biomolecules, and many other processes. Quartz crystal microbalance with dissipation monitoring has been utilized to probe the influence of several parameters on the quality of SLBs formed on Au- and SiO2-coated sensors. The influence of the aqueous medium (i.e., buffer type) and the adsorption temperature, above and below the lipid melting point, is neatly explored for SLBs of 1,2-dimyristoyl-sn-glycero-3-phosphocholine and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine formed by a solvent exchange. Below the lipid melting temperature, quality variations are observed upon the formation on Au and SiO2 surfaces, with the SLBs being more homogeneous for the latter. We further investigate how the buffer affects the detection of lipid melting in SLBs, a transition that necessitates high-sensitivity and time-consuming surface-sensitive techniques to be detected.

Development of Soft shape-memory materials is often limited to the synthesis of two-dimensional specimens and rely on bending mechanisms and scaffolding topology to perform three-dimensional morphing. Here, the authors demonstrate a shape-memory composite material made from main-chain liquid crystal elastomer microparticles dispersed in a silicone polymer matrix which enables molding into full-volume objects of any shape or size.

This paper seeks to answer to what extent the city of Vukovar is divided and in which way this division is geographically imagined and embedded in everyday life. Since each case of divided cities is driven by different factors and consists of different manifestations, case study design is the most appropriate one for researching micro-divisions in this post-conflict area. The case study of Vukovar is interesting because war legacy influenced new local policies and politics; open border issues affect bilateral relations on State level; and micro-regional frictions show deep identity-based divisions. Regardless of the lack of physical obstacles in the urban structure of the city, the research presents multilevel divisions that are visible in a form of imagined boundaries. Although Vukovar is an ethnically divided city we presume that division(s) lacks any strong geographical (or territorial) aspect. That is why the method of mental mapping on a random based sample of local population is used to compare imagined divisions in everyday life with administrative, ethnical and political ones.

This paper seeks to answer whether the concept development of education for the Croatian Armed Forces and national security may learn from Portuguese experience. By doing so, it reviewed theoretical notions of defence and security studies, contemporary concepts in education for the armed forces and national security, and it offered a case study of Portugal in this field. The current objectives of the national security in Croatia, as defined in National Security Strategy 2017, point towards the need of establishing an adequate education system, at the state level. The paper offers contemporary Portuguese experience as a potential example for implementation in Croatia.

Electrocaloric (EC) materials are prominent candidates for new generations of scalable and green refrigeration devices. While most often the research on EC materials has been focused on achieving high magnitudes of the EC temperature change, little is known about electrical losses and self-heating effects, despite playing a critical role in the cooling performance of these materials. Here, we analyzed the behavior of a set of ceramic materials under EC-device-like electric-field-driving conditions. The EC temperature response was studied focusing on the contributions to the self-heating in three different compositions: relaxor Pb(Mg1/3Nb2/3)O3 and two different (undoped and Nb-doped) rhombohedral ferroelectric Pb(Zr,Ti)O3 compositions. The specific relaxor and ferroelectric nature of the analyzed materials enabled us to separate the different contributions, such as domain switching and electrical conductivity, to their EC responses. We show that besides having a large EC temperature change, low electrical losses, leading to reduced self-heating effects, are another key parameter to be considered in the engineering of materials for future EC cooling devices.

In this paper, we explore the potential of blockchain technology to enhance public administration efficiency in Bosnia and Herzegovina. Facing challenges in communication and service delivery between the government and its citizens, our research investigates how blockchain can provide solutions. We employed questionnaires to gather citizens’ opinions and conducted a comparative analysis of best practices from countries that have successfully implemented blockchain in public sectors. This approach allows us to identify specific areas where blockchain, particularly through smart contracts and hybrid networks, can improve efficiencies and outcomes. Blockchain technology, known for its decentralization, transparency, and security features, shows promise in several sectors, including finance, cryptocurrency, business support, and law, offering substantial benefits. Our analysis suggests that by adopting similar strategies, Bosnia and Herzegovina can address many current issues undermining public administration effectiveness. Our findings, based on citizens’ feedback and international case studies, indicate that the existing system falls short in efficiency, underscoring the need for innovative solutions like blockchain to enhance public service delivery. We acknowledge potential challenges in implementation, such as technological infrastructure, legal frameworks, and socio-economic considerations. Despite these hurdles, our research presents a compelling case for blockchain technology as a means to facilitate more effective communication and services between the government and its citizens. We conclude with recommendations for adopting blockchain technology in Bosnia and Herzegovina’s public administration, supported by our comparative analysis and questionnaire insights. Additionally, we suggest areas for future research to continue exploring the transformative potential of blockchain in public services.

Edward Gorey’s works are commonly set within a hybrid Victorian/ Edwardian period and often elicit further confusion by containing comically anachronistic details and a nonsensical approach to time, all of which leads to Gorey’s characteristic “bewildering temporality” (Shortsleeve 2018: 104). As this paper shows with examples from The Broken Spoke (1976), The Object- Lesson (1958), and The Water Flowers (1976), Gorey employs manipulations of temporal boundaries within the framework of nonsense, such as simultaneity, digression, and repetition, which suggest timelessness and infinity. These are devices that necessarily draw the reader’s attention to the form, structure, and pattern of Gorey’s works, and the same is true of his intertextual quotation and nonsensical rearrangement of time-related motifs from other texts, as in the case of his parodic transplantation of Charles Dickens’ device of time-traveling ghosts (The Haunted Tea-Cosy, 1997). Nevertheless, despite a self-referential flaunting of form, Gorey’s works frequently accomplish a seriocomic confusion of tone that complicates any simplified reading of his tales as exclusively humorous. This effect, which has elicited descriptions of Gorey’s work as “radiat[ing] a melancholy and an existential unease” (Kindley 2018), is to some extent accomplished by his relatively frequent depiction of ghosts and apparitions, which inherently point toward the question of time, indicating both the past and the future. The paper concludes by exploring what implications such a bidirectional movement can have on the reader’s experience when encountering Gorey’s mysterious spectres.

In Edward Gorey’s numerous scenes of breakfasts, lunches, dinners, and afternoon teas, food and drink often feature with more or less prominence and are sometimes even found in the titles of his books, such as in The Fatal Lozenge (1960) or The Unknown Vegetable (1995). Their seemingly innocent appearance is often tied to violence or death: a head is discovered in a breadbox, a woman murders her husband by lacing his tea with atropine, a boy dies of exposure after being punished for “splashing his soup”, and several characters are consumed by more or less fantastic creatures. And yet, throughout all such gruesome events, Gorey’s characteristically playful and absurd humour adds levity to scenes of food-related death, misery, downfall, and even murder. Whether much attention is drawn to such events (such as in The Unknown Vegetable, where the entire story revolves around the discovery of a giant turnip-like vegetable that leads to a woman being buried alive) or whether they are merely mentioned in offhanded comments, Gorey couches them in a frame of the ridiculous and the nonsensical. It is therefore the aim of this paper to explore how Gorey achieves this curious combination of the grotesque and the humorous in scenes revolving around food, and how this approach extends to a general confusion of tone in his darkly funny, seriocomic creations in which any manner of horror may be lurking in peaches, cakes, crackers, boiled turnips, a recipe for fudge, a family picnic, or under a haunted tea cosy.

This article focuses on land use changes in the area of interest in the southern part of the Czech Republic (South Bohemia Region). Land use changes have been assessed at several time levels over nearly two centuries. Unlike similar studies, two types of materials were used as source data and compared. Specifically, these are historical maps or aerial photographs and the Corine Land Cover database. The evolution of land use was examined on a representative set of sixty cadastral areas, which evenly cover the territory of three different production areas of the South Bohemia Region. Each production area was then evaluated both as a whole and separately. The paper’s results confirm the trend of decreasing the share of intensively used agricultural land (arable land), especially in worse natural conditions, like in other countries of the Central European region. An essential result of the publication was also the demonstration of the unique development of the post-1948 period when there was a significant difference in land use development between the border forage production areas and the rest of the agriculturally used parts of the region.

An approach to various metal hydrides based on electronic principles is presented. The effective medium theory (EMT) is used to illustrate fundamental aspects of metal-hydrogen interaction and clarify the most important processes taking place during the interaction. The elaboration is extended using the numerous existing results of experiment and calculations, as well as using some new material. In particular, the absorption/desorption of H in the Mg/MgH2 system is analyzed in detail, and all relevant initial structures and processes explained. Reasons for the high stability and slow sorption in this system are noted, and possible solutions proposed. The role of the transition-metal impurities in MgH2 is briefly discussed, and some interesting phenomena, observed in complex intermetallic compounds, are mentioned. The principle mechanism governing the Li-amide/imide transformation is also discussed. Latterly, some perspectives for the metal-hydrides investigation from the electronic point of view are elucidated.

The piezotronic effect gained considerable interest during the last decade. It utilizes the interaction of stress-induced piezoelectric charges and the electronic band structure in piezoelectric semiconductors. This could lead to new applications like strain-triggered transistors or transparent strain/stress sensors. Apart from single Schottky barriers, double Schottky barriers in varistor boundaries in ZnO can be modified extensively by the application of stress. The gauge factors obtained by this method far exceed values for commercial strain sensors. The determination of the underlying physical mechanisms is therefore of utmost importance for applications in strain sensing. In this work, the experimental results of the influence of mechanical stress on the current–voltage characteristics of ZnO-based varistor ceramics are contrasted to simulations. It is verified that a recently introduced simplified physical model based on parallel conductive regions is capable of explaining the stress sensitivity of varistor ceramics and the evolution of the gauge factor as a function of mechanical stress. At electric fields below the breakdown voltage, small percolating pathways through the microstructure determine the current response of the ceramic. This current localization effect becomes even more pronounced when the material is mechanically stressed with an externally applied uniaxial compressive load. Considering application in stress sensors, current localization in the material could possibly lead to local heating effects and degradation of the material. [ABSTRACT FROM AUTHOR]