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Multi-index and multivariate assessment of heavy metal contamination and ecological risks in the largest deltaic Estuary of South Asia
No full textDespite the ecological and socio-economic significance of the deltaic Meghna River Estuary, comprehensive assessments of heavy metal contamination and associated ecological risks remain limited. This study aims to: (i) quantify ten heavy metals in surface sediments across three main estuarine zones (Chandpur, Hatiya and Bhola); (ii) assess contamination levels and ecological risks using integrated pollution indices; and (iii) identify pollution sources through multivariate analyses. ICP-MS analysis of sediments from Hatiya, Chandpur, and Bhola revealed spatial variation, with Hatiya showing comparatively elevated metal accumulation. The enrichment factor and geoaccumulation index (Igeo) data revealed moderate to severe pollution by arsenic, selenium, and mercury, especially in Hatiya and Chandpur. Igeo assessed Hg in Chandpur (5.49) as highly polluted, whereas Se surpassed Igeo >4 in Hatiya. The contamination factor values for arsenic indicated significant contamination, whereas the pollution load indices in Hatiya and Chandpur >1, affirming anthropogenic impact. Ecological risk assessment classified the estuary as facing moderate ecological risk, with Hatiya and Chandpur more impacted than Bhola. The Nemerow Pollution Index similarly identified Hatiya and Chandpur as pollution hotspots, likely influenced by agricultural runoff and upstream industrial effluents. Bhola showed comparatively low contamination, reflecting predominantly natural sources. Cluster analysis distinguished lithogenic from anthropogenic contributions, with arsenic, cadmium, and mercury emerging as the main pollutants of concern.No Full Tex
Deriving physically-based continuous functions for soil particle size distribution considering fragmentation and transport processes
No full textThe particle size distribution (PSD) is one of fundamental physical properties of soil. Compared with the conventional graphic parameters, the continuous function description has obvious advantages for characterizing the mathematical relationship of the PSD. In this study, unlike previous phenomenological and statistical studies, continuous functions were derived by directly developing physical and mathematical models of the key processes responsible for soil formation. The logarithmic gamma distribution was analytically derived as the solution of the fragmentation model, and a function with 5 parameters was derived as the unified distribution of real soil considering fragmentation and transport processes. Then, the proposed continuous functions were verified through a Lunar soil PSD database and the UNSODA2.0 database. The proposed functions can be used to replace the graphic parameters in soil mechanics and engineering practice to take advantage of its clear physical background and strict verification based on a large amount of data.No Full Tex
Associations of smoking, infections, early-life exposures, and concussion with progressive-onset versus relapse-onset multiple sclerosis: A case-control study
No full textBackground: Among environmental factors associated with multiple sclerosis (MS) susceptibility, few studies have examined different onset types. It remains unclear whether risk factors for primary progressive MS (PPMS) are comparable to those for relapse-onset MS (RMS). This study aimed to explore the association between selected environmental factors and PPMS risk, and compare their effect sizes with RMS. Methods: We used a case-control design with participants from two datasets: the Primary-Progressive MS Study (2015–2021) and the Australian Multi-center Study of Environment and Immune Function (2003–2006). Questionnaires collected data on smoking, infectious and concussion history before MS onset, supplement intake before age 15, and breastfeeding history. Unconditional, conditional, and weighted multivariable logistic regression evaluated associations with PPMS and RMS onset risk. Results: A significant positive association was observed between tobacco smoking prior to onset (≥20 pack-years: odds ratio (OR)=1.75, 95% confidence interval (CI)=0.96–3.20, P for trend=0.03) and history of infectious mononucleosis before MS onset (OR=1.74, 95% CI=1.05–2.88) in PPMS. Having vitamin supplements before age 15 (OR=0.52, 95% CI=0.31–0.87) and being breastfed during infancy (>6 months vs. never: OR=0.52, 95% CI=0.27–0.98) were associated with reduced PPMS risk. For RMS, tobacco smoking prior to onset (ever smoker OR=1.62, 95% CI=1.15–2.30; ≥20 pack-years: OR=2.17, 95% CI=1.20–3.80, P for trend=0.007) and infectious mononucleosis (OR=1.76, 95% CI=1.19–2.61) were also significantly associated with increased risk, with no difference in effect sizes compared to PPMS. Other infections, supplement intake, and being breastfed were not associated with RMS risk. Marijuana smoking and concussion history were not associated with either PPMS or RMS. Conclusions: PPMS shares some common risk factors with RMS, such as tobacco smoking and infectious mononucleosis, with similar effect sizes. This suggests PPMS and RMS may share underlying disease mechanisms. Further studies are needed to validate the role of other factors associated with PPMS onset.No Full Tex
The Quaternary fossil assemblage of Layang Mawas Cave (Merapoh, Pahang) in Peninsular Malaysia: context, formation, composition and age constraints
No full textLayang Mawas Cave represents the first numerically-dated Middle to Late Pleistocene fossil site in the eastern part of Peninsular Malaysia. Previous research mostly focused on the Quaternary fossil sites located in the western part of the peninsula that is distinctly separated from the east by the granitic Main Range batholith. A survey of the fossil-bearing breccia in Layang Mawas Cave yielded 21 remains, mostly tooth fragments and isolated teeth, from at least eight taxa. Stratigraphic and sedimentological evidence suggest that all the fossils found in different areas of the cave relate to the same breccia formation event. The faunal assemblage is comparable with those from five other Middle and Late Pleistocene West Malaysian sites. It also includes a new biogeographic record for Pleistocene orangutan and the first directly-dated occurrence of a Proboscidea in the region. The polymictic nature of both allochthonous and autochthonous clasts with large grain size difference in the breccia indicates an intense mixing of fauna through successive episodes of deposition and post-depositional erosion. Our study suggest that the fossils were deposited as part of natural sedimentary processes over a long history of hydraulic or gravitational transportation and reworking, possibly after being accumulated by rodents. Direct dating of a few selected teeth from the fossil assemblage using U-series and ESR methods was quite challenging given the existing uncertainty around the dose rate evaluation. Despite some apparent scatter possibly partly resulting from this intrinsic uncertainty, our results nevertheless return a Late Pleistocene (MIS 5 to 4) age for most of the fossil teeth, while a last tooth coming from another area within the chamber most likely shows an older Middle Pleistocene age (MIS 7 or older). Although all dated specimens may be in first instance related to the same breccia formation event, we cannot reasonably exclude that some of them may have been reworked from significantly older deposits or correspond to various phases of fossil accumulation.No Full Tex
The voice or the script? Unlocking AI agent persuasion through modality and mental imagery
No full textAI agents are increasingly used in marketing to deliver personalized product recommendations through text- or voice-based interactions. While prior research has focused on content characteristics, the influence of communication modality remains underexplored. This research investigates how the modality of AI agent communication (text vs. voice) shapes consumers’ recommendation adoption behavior and how this effect varies across message contexts. We first conducted a field experiment in collaboration with a local mobile phone retailer, which provided initial behavioral evidence that text-based AI recommendations lead to higher engagement than voice-based recommendations. Building on this real-world pattern, three controlled experimental studies further unpack the underlying psychological mechanism and boundary conditions. Across these studies, we show that text-based recommendations generally elicit stronger recommendation adoption behavior by facilitating vivid mental imagery. However, when embodied cognition cues are present, voice-based recommendations become more persuasive due to their alignment with sensory simulation. This pattern is further moderated by temporal framing: under near-future framing, voice with embodied cues evokes stronger imagery and engagement, whereas under distant-future framing, text remains more effective. Together, these findings position mental imagery as a core explanatory mechanism through which AI agent modality translates into consumer response, and demonstrate how aligning modality with sensory and temporal contexts can enhance the effectiveness of AI-mediated recommendations.No Full Tex
VeriFuzzy: A Dynamic Verifiable Fuzzy Search Service Framework for Encrypted Cloud Data
Full text linkEnabling search over encrypted cloud data is essential for privacy-preserving data outsourcing. While searchable encryption has evolved to support individual requirements like fuzzy matching (tolerance to typos and variants in query keywords), dynamic updates, and result verification, designing a service that supports Dynamic Verifiable Fuzzy Search (DVFS) over encrypted cloud data remains a fundamental challenge due to inherent conflicts between underlying technologies. Existing approaches struggle with simultaneously achieving efficiency, functionality, and security, often forcing impractical trade-offs. This paper presents VeriFuzzy, a novel DVFS service framework that cohesively integrates three innovations: an Enhanced Virtual Binary Tree (EVBTree) that decouples fuzzy semantics from index logic to support O(log n) search/updates; a blockchain-reconstructed verification mechanism that ensures result integrity with logarithmic complexity; and a dual-repository state management scheme that achieves IND-CKA2 security by neutralizing branch leakage. Extensive evaluation on 3,500+ documents shows VeriFuzzy achieves 41% faster search, 5× more efficient verification, and constant-time index updates compared to state-of-the-art alternatives. Our code and dataset are now open source, hoping to inspire future DVFS research.Full Tex
Implementing the design cues of dissociation dynamics and transmetalation in gallium(III) complexes to promote the anti-proliferative activity of ligands targeting intracellular iron(II) trafficking
No full textDesigning ligands for cancer has traditionally overlooked complex dissociation and transmetalation in enhancing efficacy. Another neglected criterion is the ligands' ability to intercept the labile Fe(ii) pool released after transferrin endocytosis and reduction of transferrin-bound Fe(iii). Given iron's essential role in cancer proliferation, disrupting metal homeostasis offers a promising therapeutic strategy. Herein, we introduce a new class of Fe(ii)-selective ligands and their Ga(iii) complexes for cancer therapy, guided by insights into their dissociative dynamics and transmetalation behavior. Unlike prior approaches focused on static metal coordination, this work integrates dissociation and transmetalation as design features, enabling selective interception of intracellular Fe(ii) trafficking. Relative to the ligand, Ga(iii) complexation led to a pronounced (p < 0.001-0.0001) enhancement in anti-proliferative activity, with up to a 70-fold increase in potency. This result was in contrast to the modest increase in potency (up to 2.4-fold) observed for the Cu(ii) or Zn(ii) complexes. Mechanistic dissection demonstrated that, unlike the complete dissociation of the Ga(iii) complexes, the relative Zn(ii) and Cu(ii) complexes underwent only partial dissociation. This difference facilitates complete ligand and Ga(iii) release from the complex and may account for the superior cytotoxicity of the Ga(iii) complexes versus their Zn(ii) and Cu(ii) counterparts. Furthermore, their potency was linked to Fe(ii) ligation rather than Fe(iii), despite electronic similarity to Ga(iii). This study introduces three underexplored design principles for anti-cancer ligand engineering: (i) dynamic complex dissociation; (ii) selective intracellular transmetalation using NNO-containing ligands; and (iii) interception of labile Fe(ii) generated after endosomal Fe(iii) reduction.Full Tex
Improving care in pregnancies after perinatal loss: A national survey of maternity services in Australia
No full textProblem Pregnancy following perinatal loss is associated with significant parental anxiety and potential increased risks of adverse perinatal outcomes. Background Standard antenatal care often fails to meet the needs of these families. As care provision varies widely across services, the most effective care model remains unclear. Aim To gain an overview of current pregnancy after perinatal loss practice across Australian maternity services. Methods National web-based survey administered to hospital-based maternity services, completed by a senior clinician or administrator from each service. Data were analysed descriptively. Findings Sixty-one maternity services responded. Obstetrician involvement was the most consistent element of care, reported “always” by 83 % of services and “sometimes” by 17 %. Specialist midwives were absent in 51 % of services, and 70 % did not offer antenatal classes for pregnancy after loss. While 44 % of services had a written policy/guideline for pregnancy after loss care – which appeared to emphasise medical over psychosocial care – 77 % lacked a dedicated model or specialised service. The most common barrier to providing pregnancy after loss care was the absence of a specialist bereavement role (52 %), with only 7 % reporting a lack of support from clinical staff. Discussion Despite high levels of clinician support for better meeting the needs of women during pregnancies after perinatal loss, dedicated services were infrequently reported and appeared to focus on medical components of care over psychosocial support. Conclusion Addressing policy, administrative, and workforce barriers may be an important step towards improving care for women and families during pregnancies after perinatal loss.Full Tex
How Patients Shape Healthcare: Then, Now and What's to Come?
No full textHistorically, healthcare has been paternalistic; patients were expected to be passive participants in their own healthcare, complying with healthcare professional orders without question (Longtin et al. 2010). Today, there are calls for patients to be more active participants, who partner with healthcare professionals, evaluate the care provided, and join health research teams (Ocloo and Matthews 2016). This transformation has occurred through a series of pivotal moments in industry, culture, and technology. In this commentary, I explore how patients have come to shape hospital care at every level, from the bedside to the boardroom, and challenge readers to imagine how central their voice will be to the future of nursing and hospitals.Full Tex
The impact of educational leadership on student learning practices: tracing the flow of influence
No full textThis article examines the dynamic flow of influence from leading to student’s learning practices in schools, reconceptualising leadership as a multifaceted complex of interrelated and ecologically integrated practices. Rather than privileging any single leadership role, it conceptualises leading as a coordinated social ensemble in which leaders work interdependently to shape the professional and educational conditions that support teaching and learning. Qualitative analysis of two in-depth ethnographic case studies conducted as part of a national Australian research focused on studying the influence of middle leadership aiming to show how leading practices reach learners in classrooms. It traces how practices travel from policy to principals to middle leaders to teachers, subsequently influencing student′s practices. Drawing on practice theory, findings illustrate ways leading practices create practice architectures which influence teachers′ and students′ learning. By tracing the ‘trail of evidence’ concerning specific school development initiatives being implemented in school sites, results reorient debates about the efficacy of leading school-based change towards understanding how a composite of leading practices emerges relationally and temporally through shared language, activity and responsiveness to local contexts. Findings offer an ecological interpretation of educational leadership influence, illuminating how coordinated leading practices contribute to professional learning, teaching, and student learning practices.Full Tex