Search Results (33)

Accurate determination of the propagation constant ($\gamma$) in uniform microwave lines is critical but challenging due to the requirement for complex calibration and susceptibility to measurement noise. In order to overcome these limitations, a new objective function has been derived for improved propagation constant $\gamma$ measurement of uniform lines with symmetric reflections through calibration-free line–line measurements. Well-known methods in the literature on the determination of propagation constants with reflection asymmetry and non-reciprocal behavior structures are investigated and compared. To this end, mathematical derivations related to theory of microwave networks are validated by measurements in microwave frequency range X-band (8.2–12.4 GHz). Its advantage relies on the fact that it uses a term which is in the product form of determinants of two characteristic terms, whose value is close to unity both in theory and experiments. Eigenfactor (complex exponential) and $\gamma$ measurements of an X-band uniform (empty) waveguide section with symmetric reflections were carried out to validate our proposed formalism. Full article

This paper explores what heritage conservation might become when it listens differently—when it opens itself to relational, situated, and community-led practices of care. Beginning with the provocation “Museums? I don’t think this is for us. Museums are far too clever for us,” voiced in the context of an ecomuseum, I interrogate the assumptions that underpin conventional heritage conservation: expert authority, linear temporality, and the desire to stabilize. Drawing on new materialism theories, I question the disciplinary logics that produce heritage as a human centred practice that look at objects as static and conservation as a neutral act. In contrast, I present ecomuseums not as policy model but as conceptual disruption—territories of care that emerge from entanglements of memory and place, becoming, therefore, an active force that are engaged in sustainable practices. In thinking with ecomuseum practices, I consider how conservation would look if shifted from colonial to liberative practices, from control to attention, from fixity to fluidity. I explore conservation as a field of relations—affective and unfinished. Finally, I offer a call for heritage practitioners to reimagine conservation not as the act of keeping things the same, but as an ongoing negotiation with change in a pluriversal world. Full article

The increasing availability of colloidal silver dietary supplements raises important concerns regarding their safety when used for oral consumption. This study presents the physicochemical characterization of a commercial colloidal silver solution with a high concentration (1000 mg/L), stabilized with pectin in distilled water. The characterization was performed using UV-VIS, XRD, and TEM. The manufacturer did not provide information regarding nanoparticle size or recommended duration of use. The 1000 mg/L sample was also compared with a standard colloidal silver solution provided by Sigma Aldrich to validate nanoparticle size, stability, and spectral profiles. In addition, a comparative theoretical analysis was conducted on other commercially available products containing colloidal silver at concentrations of 15, 30, 55, 80, and 125 mg/L, based solely on the recommended daily intake and the oral reference dose of 0.005 mg/kg/day established by the United States Environmental Protection Agency (EPA). Although no in vivo or in vitro toxicity tests were performed, the results indicate a potential toxicological risk due to estimated intake levels that may exceed safety thresholds, particularly in high-concentration products with insufficient labelling or unclear usage guidelines. These findings emphasize the need for stricter regulatory measures and greater public awareness regarding the internal use of colloidal silver supplements. Full article

Despite the impressive properties of additively manufactured products, their inherent anisotropy is a crucial challenge for polymeric parts made via fused filament fabrication (FFF). This study compared the tensile, thermophysical, smoke density, and toxicity characteristics of Ultem 9085 (a blend of polyetherimide and polycarbonate) for samples printed in various orientations (X, Y, and Z). The results revealed that mechanical properties, such as elastic modulus and tensile strength, significantly differed from the Z printing orientation, particularly in the X and Y printing layer orientations. Thermomechanical analysis revealed that Ultem 9085 had high anisotropic effects in the coefficient of thermal expansion, indicating superior thermal properties along the printing orientation. The smoke density and toxicity test results proved that Ultem 9085 complies with aviation safety standards. Smoke density tests showed that all samples, regardless of print orientation or thickness, stayed well below the regulatory limit, making them suitable for aircraft interiors. Full article

With the increasing concern about global warming and future climate change, attention has been drawn to the need to reduce building energy use through improving buildings’ energy efficiency. Existing residential buildings constitute the largest percentage of energy demand and carbon dioxide emissions, and hence, offer significant potential for energy savings and reductions in greenhouse gas emissions. This review aimed to provide an in-depth analysis of current research on improving the energy efficiency of existing residential buildings in Libya and neighbouring Mediterranean countries, with a focus on research methods and tools utilised in this domain. This helped to identify potential areas of intervention to improve the energy efficiency of existing residential stock in Libya. Under identified themes, this study systematically analysed 44 publications of high relevance to the subject area found in Scopus, ScienceDirect, and Google Scholar. The results reveal that while energy retrofitting is a research area of interest in the region considered, studies in the Libyan context are limited. There is also limited attention to achieving net zero energy and embodied carbon reductions, specifically in the Libyan context. Moreover, some weaknesses were identified for most of the studies reviewed, including those in the Libyan context, related to the credibility and reliability of the energy models used in the various literature. Full article

Jinchanshan is a medium-sized, granitoid-hosted gold deposit located in the Kalaqin area of Inner Mongolia. Mineralization predominantly occurs in the contact zone between biotite granites and quartz porphyry rocks, associated with the Jinchanshan minor intrusion, suggesting a genetic link to the granitoid-hosted gold deposit. In this study, the petrography, geochemistry, and LA-ICP-MS zircon U–Pb chronology of these two granitoid samples were studied. The results indicate that the zircon U–Pb age of the biotite granites is 127.9 ± 3.0 Ma, while that of the quartz porphyry is 121.4 ± 1.5 Ma, both dating back to the Early Cretaceous. The average SiO₂ content of the granites is 66.64%, and the rocks have high total alkali (K₂O + Na₂O) content, averaging 9.13%. The average K₂O content is 4.39%, with a K₂O/Na₂O ratio of 0.93. The quartz porphyry rocks are enriched in SiO₂ (74.41%–76.85%) and have high Na₂O + K₂O content (8.67%–9.59%), but are low in MgO (0.03%–0.09%), CaO (0.44%–1.02 %), and TiO₂ (0.08%–0.12%). Most samples of the biotite granite and the quartz porphyry rocks exhibit high-K peraluminous and medium-K calc-alkaline characteristics, respectively. Both rock types are enriched in Rb, Th, U, K, Zr, Hf, and Gd and relatively depleted in Ba, Sr, P, Ti, Nb, Ta, and Eu, with a pronounced negative Eu anomaly. The biotite granites show high ∑LREE/∑HREE ratios (6.1–6.9), while the quartz porphyry rocks exhibit lower ratios (2.0–4.2). Both granitoid types have elevated FeO^T content and FeO^T/(FeO^T + MgO) ratios, indicating that the Jinchanshan granitoids are A-type granites. The zircon U–Pb ages, combined with the regional tectonic settings, suggest that these granitoids formed during large-scale metallogenic events in the Early Cretaceous, within the Yanshanian post-orogenic extensional tectonic regime. This is consistent with the lithospheric thinning and extensional processes in Eastern China during this period. Full article

Transition economies, on the one hand, grapple with a communist legacy; on the other hand, they seek the optimal institutionalization for knowledge generation, dissemination, and commercialization to compete globally. However, the incumbent knowledge of certain aspects of their innovation systems remains very limited. In particular, intra-organizational cultural relics of the past and their inter-organizational and, consequently, systemic implications require research. This study examines how interaction barriers among universities, industry, and government, stemming from intra-organizational cultures, impact structural change in the innovation system of Azerbaijan. Utilizing the TH model, interviews with 59 participants revealed that a “Statist” TH model in Azerbaijan hinders organic cultural development within organizations, leading to interaction issues among TH actors. Moreover, problems in inter-organizational communication pave the way for a systemic failure that necessitates government intervention, strengthening the “Statist” TH model. The findings increase the context sensitivity of the TH framework by exploring an understudied context and provide valuable insights relevant to other transition economies facing similar institutional legacies. Full article

This article examines humanist anecdotes about the turbulent times of the mid-twentieth century by F. C. Weiskopf and Lenka Reinerová. It provides a comparative reading of Weiskopf’s Elend und Größe unserer Tage. Anekdoten 1933–1947 (1950) and Reinerová’s “Tragischer Irrtum und richtige Diagnose” (published in Mandelduft, 1998). The anecdotal form of these texts harks back to the popular Enlightenment (Volksaufklärung) anecdotes of Heinrich von Kleist and Johann Peter Hebel, published in 1810–1811 during the Napoleonic Wars. The anecdote as a literary form is particularly well suited to the representation of wartime and political repression. While Weiskopf’s anecdotes explore cruelty and heroism under the Nazi dictatorship, Reinerová’s autobiographical text juxtaposes crisis points in her own life—her time as a political prisoner in France in 1939 and in Czechoslovakia in 1952–1953; her return to Prague as her family’s sole survivor; and her periodic cancer treatment from 1948 onwards. Reinerová describes how the kindness of ordinary people, and her own optimism and resilience, helped her through the worst times. Her lived experience gives her authority as a storyteller in Walter Benjamin’s sense. Both authors contrast human extremes—the good and the bad—yet both remain optimistic about the human capacity for good. Full article

Bedded barite, Fe-Zn-Pb sulfides, carbonates, and cherts within Ediacaran (Dalradian Supergroup) graphitic metasediments near Aberfeldy in Scotland have previously been interpreted as chemical sediments precipitated from hydrothermal fluids episodically exhaled into marine basins filled with organic-rich mud, silt, and sand. Lithological variation and compositional diversity in pyrite and sphalerite reflect varied redox environments and proximity to hydrothermal discharges. Thick beds (>2 m) of barite have relatively uniform δ³⁴S of +36 ± 1.5‰, considered to represent contemporaneous seawater sulfate, as negative Δ¹⁷O indicates incorporation of atmospheric oxygen during precipitation in the water column. However, certain features suggest that diagenetic processes involving microbial sulfate reduction modified the mineralogy and isotopic composition of the mineralization. Barite bed margins show decimeter-scale variation in δ³⁴S (+32 to +41‰) and δ¹⁸O (+8 to +21‰), attributed to fluid-mediated transfer of dissolved barium and sulfate between originally porous barite and adjacent sediments, in which millimetric sulfate crystals grew across sedimentary lamination. Encapsulated micron-sized barium carbonates indicate early diagenetic barite dissolution with incorporation of sulfur into pyrite, elevating pyrite δ³⁴S. Subsequently, sulfidation reactions produced volumetrically minor secondary barite with δ³⁴S of +16 to +22‰. Overall, these processes affected small volumes of the mineralization, which originally formed on the seafloor as a classic SEDEX deposit. Full article

Zn²⁺ has a crucial role both in biology and the environment, while Pb²⁺ presents serious hazards in the same areas due to its toxicity, and the need for their analysis often exceeds available instrumental capacity. We report, herein, a new high-throughput optochemical screening method for Zn²⁺ and Pb²⁺ in various solutions. Moreover, we also introduced a new and generalizable three-step-microplate-modification technique, including plasma treating, linker-docking and photocatalytic copolymerization. The surface of a commercially available 96-well-cycloolefin-microplate was treated with atmospheric plasma, and then, the bottoms of the wells were covered by covalently attaching a methacrylate-containing linker-monolayer. Finally, the preactivated microplate wells were covalently functionalized by immobilizing bis(acridino)-crown ether-type sensor molecules, via photocatalytic copolymerization, to a polymethacrylate backbone. This sensing tool can be used in all microplate readers, is compatible with liquid handling platforms and provides an unprecedently fast monitoring (>1000 samples/hour, extrapolated from the time required for 96 measurements) of dissolved Zn²⁺ and Pb²⁺ among recent alternatives above the detection limits of 8.0 × 10⁻⁹ and 3.0 × 10⁻⁸ mol/L, respectively, while requiring a sample volume of only 20 µL. Full article

There is a strong relationship between heritage-led urban regeneration and the UN initiatives for Sustainable Development (SD). These include the Intangible Cultural Heritage Convention (ICH; 2003) and Historic Urban Landscape (HUL; 2011) under the UNESCO mandate and the Sustainable Development Goals (SDGs; 2015) and the New Urban Agenda (NUA; 2016) under the UN mandate. Despite the presence of those initiatives, regeneration in a World Heritage city often leads to the disappearance of intangible heritage, gentrification, excessive tourism, and social exclusion. Therefore, this paper critically identifies the shortcomings of those initiatives in addressing social and cultural sustainability. It uses the recently inscribed city of As-Salt on the WHL to showcase how the relevant SDGs’ targets and indicators are problematic in monitoring and measuring the sustainability of urban regeneration practices in WH cities. This is achieved by investigating where heritage and culture are embedded within the descriptions of goals and indicators in the three initiatives (SDGs, NUA, and HUL) document. A content analysis, using the NVivo qualitative data analysis tool, was conducted in order to identify complementarity, synergies, and correlations among the goals and indicators related to social and cultural sustainability. This paper concludes by suggesting an integrated approach under the umbrella of the SDGs for a more sustainable heritage-led urban regeneration alternative for cities acquiring UNESCO WH status. Full article

Climate change is exerting significant impacts on ecosystems worldwide, with alpine regions being particularly vulnerable. Alpine fauna is relatively poorly understood, particularly in terrain which is difficult for humans to survey. Knowledge of alpine species is further limited by a paucity of survey techniques that are widely applicable in this environment. Drones have potential as a low-impact tool for surveying fauna in remote alpine terrain. New Zealand’s diverse alpine lizards are an ideal system for exploring novel survey techniques. We build on previous research demonstrating the potential of drones for surveying alpine lizards by evaluating (1) how closely a drone can approach different alpine lizard species in scree, talus, and tussock-grassland habitats and (2) the effectiveness of drone surveys compared to traditional systematic visual searches for these species and habitats. The drone (model: DJI Mavic Air 2) was able to approach within 0.1–2.5 m of a lizard (mean = 0.77 m) before triggering a flight response. Systematic visual searches outperformed drone surveys in all habitats accessible to human observers. However, drones were relatively effective in talus habitats, demonstrating their potential utility in inaccessible rocky alpine habitats. Improvements to drone technology may further enhance the utility of drone-based surveys in ecological research. Full article

Polymer materials are increasingly widely used in high-fire-risk applications, such as aviation interior components. This study aimed to compare the tensile, thermal, and flame-retardant properties of test samples made from ultra-performance materials, polyetherimide (PEI) and polyetherketoneketone (PEKK), using the fused filament fabrication process (FFF). The tensile tests were performed for these materials at different raster angles (0, 45, and 90°). The thermomechanical tests were done in the axial, perpendicular, and through-thickness directions to the extruded filaments. The impact of printing parameters on the flame retardancy of 3D-printed samples was investigated in vertical burn tests with varying specimen thicknesses and printing directions. Experimentally, it was testified that PEKK had better isotropic behaviour than PEI for mechanical performance, thermal expansion, and fire-resistant properties, which are essential in fabricating intricately shaped products. Full article

Policymakers are implementing a combination of various travel demand management (TDM) policies to effectively reduce carbon emissions. Widespread acceptance of these policy mixes by residents plays a pivotal role in ensuring their successful implementation. Drawing upon the value–belief–norm (VBN) theory and policy-specific beliefs (perceived freedom, perceived fairness, and perceived effectiveness), this study evaluates the impact of low-carbon travel psychology and policy characteristics on the acceptability of a policy mix formed by the combination of mandatory measures and guiding measures within TDM. The empirical analysis leverages survey data obtained from 839 participants and employs a structural equation model. The results indicate that low-carbon travel willingness, perceived fairness, and perceived effectiveness significantly influence acceptability. Consequently, fostering low-carbon travel willingness among residents is essential for enhancing overall policy acceptability. Moreover, policy mixes that encompass incentives for the development of new energy vehicles (NEVs) are generally considered the most acceptable among residents due to their non-restrictive impact on private car usage. Given this analysis, policymakers should consider designing policy mixes that balance acceptability and effectiveness, such as incorporating policies for the development of NEVs, to address traffic pollution. Full article

(1) Background: Stereological estimations significantly contributed to our understanding of lung anatomy and physiology. Taking stereology fully 3-dimensional facilitates the estimation of novel parameters. (2) Methods: We developed a protocol for the analysis of all airspaces of an entire lung. It includes (i) high-resolution synchrotron radiation-based X-ray tomographic microscopy, (ii) image segmentation using the free machine-learning tool Ilastik and ImageJ, and (iii) calculation of the airspace diameter distribution using a diameter map function. To evaluate the new pipeline, lungs from adult mice with cystic fibrosis (CF)-like lung disease (βENaC-transgenic mice) or mice with elastase-induced emphysema were compared to healthy controls. (3) Results: We were able to show the distribution of airspace diameters throughout the entire lung, as well as separately for the conducting airways and the gas exchange area. In the pathobiological context, we observed an irregular widening of parenchymal airspaces in mice with CF-like lung disease and elastase-induced emphysema. Comparable results were obtained when analyzing lungs imaged with μCT, sugges-ting that our pipeline is applicable to different kinds of imaging modalities. (4) Conclusions: We conclude that the airspace diameter map is well suited for a detailed analysis of unevenly distri-buted structural alterations in chronic muco-obstructive lung diseases such as cystic fibrosis and COPD. Full article