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Heavy metal contamination and assessment of radioactivity in coastal sediments: a case study from the El Qulaan area, southern Red Sea, Egypt
No full textThis study investigated the concentrations, spatial distribution, and associated ecological and health risks of nine metals in the sediments of the El Qulaan region along the Red Sea coast in southern Egypt. The levels of barium (Ba), lead (Pb), chromium (Cr), nickel (Ni), and vanadium (V) exceeded both the Canadian soil quality guidelines and the Earth’s average shale composition. Nickel concentrations surpassed the Effect Range Median (ERM), while Pb, Cr, and Ni levels exceeded the Probable Effect Level (PEL), suggesting potential adverse effects on local marine organisms. Factor analysis revealed three main factors: the first factor (F1), accounting for 24% of the variance, included Ba, Co, Cr, V, Fe, pH, and total organic matter (TOM%); the second (F2, 20%) comprised Cu, Ni, and Zn; and the third (F3, 19%) included Pb, Gravel%, Sand%, and Mud%. Contamination factor (CF) values indicated varying degrees of pollution: low for Co and Cu, moderate for Pb, Zn, and Fe, considerable for Cr, Ni, and V, and high for Ba. The geo-accumulation index classified all metals as contributing to extreme contamination. The potential ecological risk index (PERI) ranged from 49 to 81, indicating a low ecological risk (PERI <150). Other indices, including the mean effects range-median quotient, toxic risk index, and modified hazard quotient, pointed to moderate toxicity and contamination severity. Non-carcinogenic risk assessments revealed no long-term health concerns, and cancer risk values remained below internationally accepted safety thresholds. Natural radioactivity levels in the sediments were also mapped and analyzed. The mean activities of 232Th, 226Ra, and 40K were 25.43 ± 7.54, 19.99 ± 6.84, and 294.92 ± 77.86 Bq/kg, respectively, all falling below global safety limits. The findings highlight the pressing need for targeted mitigation efforts and policy measures to manage metal contamination in the region’s coastal environments
Trace element zoning and temperature variation in sphalerite from the giant Nannihu porphyry-skarn-epithermal polymetallic system, central China
No full textThe Nannihu ore field at the southern margin of the North China Craton is a typical magmatic-hydrothermal metallogenic system consisting of the large Nannihu porphyry Mo-W deposit, Luotuoshan skarn Zn-Cu-W deposit, and Lengshuibeigou epithermal Pb-Zn-Ag deposit. Sphalerite is present as a minor to major phase in all these deposits, providing an ideal object to investigate its trace element zoning and temperature variation. The field data and associated mineral assemblages indicate that only one type of sphalerite is present at the Nannihu porphyry deposit, whereas two types of sphalerite are present at both the Luotuoshan skarn deposit and Lengshuibeigou epithermal deposit. Sphalerite from the Nannihu porphyry deposit has Ga, Cd and In concentrations of 0.64–7.26 ppm, 1426–1687 ppm and 291–460 ppm, respectively. In the Luotuoshan skarn deposit, sphalerite contains relatively high In (147–616 ppm) and moderate Cd (1234–1558 ppm), with low Ga (below 43 ppm). Sphalerite from the Lengshuibeigou epithermal deposit has Ga, Cd, and In contents of 3.70–589 ppm, 1453–2673 ppm, and 26.7–308 ppm, respectively. Germanium concentrations are low in sphalerite (< 5 ppm) from all three deposits. Infrared microthermometry of sphalerite-hosted fluid inclusions reveals that the sphalerite in the Luotuoshan deposit precipitated from intermediate- to low-salinity fluids (4.0 ~ 13.7 wt% NaCl equiv) at 398 to 308 ℃, whereas the Lengshuibeigou deposit formed from low-salinity fluids (2.5 ~ 7.4 wt% NaCl equiv) at 305 to 238 ℃. Indium tends to be enriched in sphalerite of the proximal high-temperature Luotuoshan skarn deposit, whereas Ga is more concentrated in sphalerite from the distal lower-temperature Lengshuibeigou deposit. Gallium and In distributions, combined with data collected from other magmatic-hydrothermal ore fields and deposits, reveal that In-enriched sphalerite occurs in proximal skarn deposits of magmatic-hydrothermal systems, and Ga-enriched sphalerite usually occurs in distal and shallow epithermal deposits. Ga/In values of sphalerite are related to the distance between mineralization and the causative intrusion of the magmatic-hydrothermal systems, and can be an indicator for exploration targeting
Model accuracy for the prediction of unreinforced clay brick masonry shear wall resistance
No full textAssessment of the accuracy of the predictive models of ultimate load resistance provisioned in design standards is essential to ensuring a minimum level of safety-in-design is maintained. Failure to apply accurate models may lead to overly conservative and non-economical designs, or structures that are unsafe at their intended ultimate limit state. This paper compares the predictive in-plane shear resistance models specified by the European, Canadian, Australian and U.S. masonry design standards, CSA S304-14 (CSA S304-14: Design of masonry structures. Canadian Standards Association, Mississauga, 2014), AS 3700 (AS3700: Masonry structures, Standards Australia, Sydney, 2018), EN 1996-1-1 (EN1996-1-1: Eurocode 6: design of masonry structures—Part 1–1:general rules for reinforced and unreinforced masonry structures, European Committee for Standardization, Brussels, 2022), and TMS 402/602-22 (TMS 402/602-22 Building code requirements and specification for masonry structures, The Masonry Society, Colorado, 2022) to the shear capacities determined experimentally from 72 full-scale cyclic shear tests on fully bedded, unreinforced clay-brick masonry walls. From these comparisons, the predictive capability of these design provisions has been assessed, and the model uncertainty has been derived in probabilistic terms to facilitate future reliability-based investigations
Exploring environmentally friendly localised corrosion inhibitors through local electrochemical measurements using multielectrode arrays
No full textLocalised corrosion is the result of complex heterogeneous electrochemical processes occurring on metal surfaces. Localised corrosion control is one of the most difficult issues in corrosion science and engineering. This study reports a new approach to exploring effective and environmentally friendly localised corrosion inhibitors through local electrochemical measurements using multielectrode array probes. Local galvanic current, local polarisation, and local electrochemical impedance spectroscopy (EIS) measurements were performed on an electrode array probe exposed to waterline corrosion conditions, with and without the presence of rare earth metal (REM) inhibitors that are known to be effective for inhibiting general corrosion. The results revealed significant differences in the behaviour of two REM inhibitors, with La(4OHcin)3·5H2O exacerbating localised corrosion by generating intense anodic sites with high local corrosion current densities, while [Y(mbp)3.H2O] showing the ability of inhibiting localised corrosion. Such localised corrosion inhibition ability by [Y(mbp)3.H2O] was found to be associated with the formation of an inhomogeneous surface film that allows the existence of minor anodes randomly distributing over the surface, leading to low anodic current densities and insignificant general corrosion rather than severe localised corrosion. These results demonstrate a new approach to discovering localised corrosion inhibitors through local electrochemical measurements using electrode arrays
Exploring sustainability oriented innovations in tourism: insights from ecological modernization, diffusion of innovations, and the triple bottom line
No full textSustainability-oriented innovations (SOIs) are reshaping the tourism industry by addressing environmental, economic, and social challenges. This study synthesises existing research on the impacts of SOIs in tourism through a bibliometric analysis of 88 studies from Scopus. Using Ecological Modernisation Theory (EMT), Diffusion of Innovations (DoI) Theory, and Triple Bottom Line (TBL) Theory, the research highlights the contribution of SOIs to sustainable tourism development. The findings indicate that SOIs enhance environmental sustainability by promoting resource conservation and pollution reduction via green technologies. Economically, SOIs improve financial performance, operational efficiency, and competitiveness while generating revenue through green certifications and eco-labels. Socially, they foster community involvement, customer satisfaction, and social equity. Quantitative methods, such as surveys and regression analysis, are predominant in existing research, complemented by qualitative and mixed-method approaches. This study also identifies critical gaps in the literature, including the long-term impacts of SOIs, the role of technology and green finance, and the effectiveness of green certifications. Addressing these gaps could guide policymakers, tourism practitioners, and stakeholders in advancing sustainable practices and policies. The findings underscore the potential of SOIs to drive sustainable development in tourism and offer valuable insights for future research directions
Unpacking tourism blind boxes: consumer experiences and purchase drivers?
No full textTourism blind boxes represent tourism products–typically hotel, airline, and package tours–that are purchased without knowing their exact nature or details. Despite its continuous expansion in size and scope worldwide, little is understood about the overall experiences of consuming tourism blind boxes. This study adopted a qualitative design, combining online comments and in-depth interviews, to obtain a comprehensive understanding. The analysis suggests five features of the consumer experience, including uncertainty, scarcity, functionality, aesthetics, and symbolic meanings. Tourism blind boxes are different from physical blind boxes in terms of functionality-oriented, higher requests for consumer deliberations, and delayed uncertainty resolution. Accordingly, four propositions were presented to explain the mental journey of purchasing tourism blind boxes. Specifically, the expectation for hedonic and utilitarian outcomes enhances purchase intention, whereas the delays in uncertainty resolution exert a negative impact. Trust, perceived control, and embodiment can modulate the effect. Practical implications of implementing the blind box selling strategy in the tourism area were discussed
Experiences with AI-Generated Pornography: A Quantitative Content Analysis of Reddit Posts
No full textWith the rise of generative artificial intelligence (AI), a new form of pornography has emerged: AI-generated pornography (AI pornography, AI adult content, synthetic pornography). This phenomenon encompasses both entirely fictional content and deepfake pornography, which involves non-consensual depictions of celebrities and private individuals. While non-consensual deepfake pornography has sparked widespread concern, the broader range of experiences associated with AI pornography remains under-researched. This study aimed to address this gap by examining the spectrum of AI pornography experiences as shared on Reddit, adopting a communication process perspective. Specifically, it explored the following research questions (RQ): How do Reddit users address the production (RQ1), content (RQ2), use (RQ3), effects (RQ4), and ethical–legal implications (RQ5) of AI pornography in their posts? A total of 390 English-language public Reddit posts related to AI pornography were collected in August 2024 and analyzed using a manual quantitative content analysis guided by a reliability-tested codebook (mean Cohen’s kappa=0.88). The analysis revealed that the production (RQ1: 59.5%) and content (RQ2: 60.8%) of AI pornography were the most frequently discussed topics, while use experiences (RQ3: 12.8%) were the least represented. Effects (RQ4: 37.2%) and ethical–legal implications (RQ5: 35.1%) were addressed in approximately one-third of posts. The AI pornography experiences addressed in Reddit posts ranged from outrage and concern regarding its actual and potential harms to curiosity, enjoyment, and economic benefits, underscoring the need for a nuanced response from policymakers, technology developers, educators, and mental health professional
Assessing Child Maintenance Cases in Ghana: What Do Social Workers Consider?
No full textWhile one of the key responsibilities of social services in Ghana is to conduct maintenance arrangements so that the nonresident parent is committed to making financial contributions to the well-being of the child, little is known about what informs social workers’ assessments in child maintenance cases. The aim of this study was to determine what social workers consider when undertaking child maintenance assessments. A qualitative practice research study was conducted with 13 social workers and 12 parents involved in a child maintenance case with three agencies of the Department of Social Welfare and Community Development in Ghana. The study showed that corroborating the existence of nonpayment for maintenance in the family is the first step in assessing other factors, such as the parent’s income, occupational status and maintenance amount. Even after the maintenance amount was decided upon, social workers were often unable to follow-up on nonresident parents to ensure that they complied with the maintenance arrangements. Given that no assessment instrument exists in Ghana for addressing child maintenance cases, the study’s findings can provide useful information that can aid in the development of an instrument or framework to assist social workers in their assessments
ScIsoX: a multidimensional framework for measuring isoform-level transcriptomic complexity in single cells
No full textSingle-cell isoform analysis enables high-resolution characterization of transcript expression, yet analytical frameworks to systematically measure transcriptomic complexity are lacking. Here, we introduce ScIsoX, a computational framework that integrates a novel hierarchical data structure, a suite of complexity metrics, and dedicated visualization tools for isoform-level analysis. ScIsoX supports systematic exploration of global and cell-type-specific isoform expression patterns arising from alternative splicing, revealing multidimensional complexity signatures across diverse datasets—insights often missed by conventional gene-level approaches. We demonstrate the utility of ScIsoX across multiple real-world single-cell isoform sequencing datasets, showcasing its potential as a general framework for transcriptomic complexity analysis
Electrochemical Biosensing for Antibiotic-Resistant Bacteria: Advances, Challenges, and Future Directions
No full textThe rapid rise of antibiotic-resistant bacteria (ABR) presents an urgent global health challenge, necessitating the development of efficient and scalable diagnostic technologies. Electrochemical biosensors have emerged as a promising solution, offering high sensitivity, specificity, and adaptability for point-of-care applications. These innovative platforms utilize bio-recognition elements, advanced electrode materials, microbial enzymes, and redox-active metabolites to identify antibiotic resistance profiles at a molecular level. Recent progress in microfluidics and lab-on-a-chip systems has enabled real-time, high-throughput antimicrobial susceptibility testing, significantly improving diagnostic precision and speed. This review aims to critically evaluate recent advances in electrochemical biosensing strategies for detecting ABR, identify key challenges, and propose future directions to enhance clinical applicability. Key developments include bio-receptor-based detection strategies, novel electrode surfaces, and multiplexed platforms integrated with microfluidic systems. Additionally, this review examines essential biomarkers for detecting antibiotic resistance and explores key challenges, including variability in biomarker expression and sensor reproducibility. It also highlights practical barriers to clinical implementation, such as cost constraints and scalability concerns. By presenting innovative approaches, such as cost-effective material alternatives, advanced analytical techniques, and portable biosensing systems, this review outlines a strategic pathway for enhancing the accessibility and effectiveness of electrochemical biosensors in antibiotic resistance management