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Collaboratively advancing our understanding of electromagnetic fields:what do you need to know?
No full textBeyond Classical Diffusion:Fractional Derivatives in Transport and Stochastic Systems
No full textInteger-order differential operators were originally used to describe local and isotropic effects, in both space and time. However, in fields like biology, the modelling of complex phenomena with spatial heterogeneity necessitates more advanced approaches. The fractional calculus framework provides powerful tools for developing models that better capture the intricate dynamics of biological systems. This paper derives fractional reaction-diffusion equations from continuous-time random walks, highlighting the role of heavy-tailed distributions in the process. Both fractional partial differential equations, on the macroscopic level, as well as fractional stochastic differential equations, on the microscopic level, will be derived and simulated from, for simple Riesz-fractional diffusion models. A new numerical scheme that implements periodic boundary conditions is proposed to control the loss of mass density. We highlight the key differences between fractional and classical diffusion
Harmonious colourings of temporal matchings
No full textGraph colouring is a fundamental problem in computer science, with a large body of research dedicated to both the general colouring problem and restricted cases. Harmonious colourings are one such restriction, where each edge must contain a globally unique pair of colours, i.e. if an edge connects a vertex coloured x with a vertex coloured y, then no other pair of connected vertices can be coloured x and y. Finding such a colouring in the traditional graph setting is known to be NP-hard, even in trees. This paper considers the generalisation of harmonious colourings to Temporal Graphs, specifically (k,t)-Temporal matchings, a class of temporal graphs where the underlying graph is a matching (a collection of disconnected components containing pairs of vertices), each edge can appear in at most t timesteps, and each timestep can contain at most k other edges. We provide a complete overview of the complexity landscape of finding temporal harmonious colourings for (k,t)-matchings. We show that finding a Temporal Harmonious Colouring, a colouring that is harmonious in each timestep, is NP-hard for (k,t)-Temporal Matchings when k≥2,t≥4, or when k≥3 and t≥2. We further show that this problem is inapproximable for t≥2 and an unbounded value of k, and that the problem of determining the temporal harmonious chromatic number of a (2,3)-temporal matching can be determined in linear time. Finally, we strengthen this result by a set of upper and lower bounds of the temporal harmonious chromatic number both for individual temporal matchings and for the classes of (k,t)-temporal matchings, paths, and cycles
An account on structure, synthesis and application of polythiophene and swelling behaviour of non-conducting polymers
No full textPolymer matrixes are studied extensively due to their unique chemical and mechanical properties and a wide field of applications. Conducting polymers are utilized as the active materials for solid-state devices viz. batteries, LED and sensors. The present article discusses the application of polythiophene as an active material for energy active devices. In addition, the authors have worked on enhancing the ionic conduction of non-conducting polymers like poly[ethylene oxide]. Solvent diffusion mechanism of non-conducting polymer–salt composite is nonlinear in nature. Swelling tendency of polymer composite can be influenced to physical, chemical and morphological behaviour. Ionic conductivity phenomena of polymer–salt composite are also influenced by the solvent
In-utero exposure to PM<sub>2.5</sub> and adverse birth outcomes in India:geostatistical modelling using remote sensing and demographic health survey data 2019–21
No full textThis study investigates the influence of air quality on birth weight and preterm birth. Utilizing data from the national family health survey and raster images, the study employs various statistical analyses and spatial models to elucidate the connection between in-utero exposure to air pollution and birth outcomes, both at the individual and district levels. It was observed that approximately 13% of children were born prematurely, and 17% were born with low birth weight. Increased ambient particulate matter 2.5 concentrations during pregnancy were associated with higher odds of low birth weight (AOR: 1.4; 95% CI: 1.29–1.45). Mothers exposed to particulate matter 2.5 during pregnancy had a heightened likelihood of delivering prematurely (AOR: 1.7; 95% CI: 1.57–1.77) in comparison to unexposed mothers. Climatic factors such as rainfall and temperature had a greater association with adverse birth outcomes. Children residing in the Northern districts of India appeared to be more susceptible to the adverse effects of ambient air pollution. Employing a distributed spline approach, the study identified a discernible upward trend in the risk of adverse birth outcomes as the level of exposure increased, particularly following an exposure level of 40 particulate matter 2.5 ug/m3. A 10 μg m − 3 increase in particulate matter 2.5 exposure was associated with a 5% increase in the prevalence of low birth weight and a 12% increase in preterm birth. Among the different spatial models used in this study, the multiscale geographically weighted regression spatial model showed the best fit to the actual scenario, effectively capturing the spatial relationships between particulate matter 2.5 exposure and adverse birth outcomes. In addition to addressing immediate determinants such as nutrition and maternal healthcare, it is imperative to collaboratively address distal factors encompassing both indoor and outdoor pollution to attain lasting enhancements in child health
Distinct adaptation and epidemiological success of different genotypes within <i>Salmonella enterica</i> serovar Dublin
No full textSalmonella Dublin is a host-adapted, invasive nontyphoidal Salmonella (iNTS) serovar that causes bloodstream infections in humans and demonstrates increasing prevalence of antimicrobial resistance (AMR). Using a global dataset of 1303 genomes, coupled with in vitro assays, we examined the evolutionary, resistance, and virulence characteristics of S. Dublin. Our analysis revealed strong geographical associations between AMR profiles and plasmid types, with highly resistant isolates confined predominantly to North America, linked to IncC plasmids co-encoding AMR and heavy metal resistance. By contrast, Australian isolates were largely antimicrobial-susceptible, reflecting differing AMR pressures. We identified two phylogenetically distinct Australian lineages, ST10 and ST74, with a small number of ST10 isolates harbouring a novel hybrid plasmid encoding both AMR and mercuric resistance. Whereas the ST10 lineage remains globally dominant, the ST74 lineage was less prevalent. ST74 exhibited unique genomic features including a larger pan genome compared to ST10 and the absence of key virulence loci, including Salmonella pathogenicity island (SPI)-19 which encodes a type VI secretion system (T6SS). Despite these genomic differences, the ST74 lineage displayed enhanced intracellular replication in human macrophages and induced less pro-inflammatory responses compared with ST10, suggesting alternative virulence strategies that may support systemic dissemination of ST74. The Vi antigen was absent in all ST10 and ST74 genomes, highlighting challenges for serotyping and vaccine development, and has implications for current diagnostic and control strategies for S. Dublin infections. Collectively, this study represents the most comprehensive investigation of S. Dublin to date and, importantly, has revealed distinct adaptations of two genotypes within the same serovar, leading to different epidemiological success. The regional emergence and evolution of distinct S. Dublin lineages highlight the need to understand the divergence of intra-serovar virulence mechanisms which may impact the development of effective control measures against this important global pathogen
Paraglacial geomorphology
No full textParaglacial geomorphology is the study of the ways in which nonglacial earth-surface processes conditioned by glaciation and deglaciation affect glaciated landscapes during and after ice retreat. Paraglacial landscape modification encompasses rockfalls and rock-slope failures, mass movement on sediment-mantled slopes, modification of glacier forelands, adjustments of fluvial systems to changing discharge and sediment flux, lacustrine and fjord sedimentation, and the sediment budget and associated landforms of barrier coasts. Most paraglacial processes peak in intensity soon after deglaciation, but may be rejuvenated by extreme climatic events, changes in base level, seismicity and anthropogenic activity. The duration of paraglacial effects ranges from decades on some recently deglaciated terrain to >105 years in large catchments and along some barrier coastlines
Hexosamine biosynthesis disruption impairs GPI production and arrests <i>Plasmodium</i> <i>falciparum</i> growth at schizont stages
No full textUDP-N-acetylglucosamine (UDP-GlcNAc) is a crucial sugar nucleotide for glycan synthesis in eukaryotes. In the malaria parasite Plasmodium falciparum, UDP-GlcNAc is synthesized via the hexosamine biosynthetic pathway (HBP) and is essential for glycosylphosphatidylinositol (GPI) anchor production, the most prominent form of protein glycosylation in the parasite. In this study, we explore a conditional knockout of glucosamine-6-phosphate N-acetyltransferase (PfGNA1), a key HBP enzyme. PfGNA1 depletion led to significant disruptions in HBP metabolites, impairing GPI biosynthesis and causing mislocalization of the merozoite surface protein 1 (MSP1), the most abundant GPI-anchored protein in the parasite. Furthermore, parasites were arrested at the schizont stage, exhibiting severe segmentation defects and an incomplete rupture of the parasitophorous vacuole membrane (PVM), preventing egress from host red blood cells. Our findings demonstrate the critical role of HBP and GPI biosynthesis in P. falciparum asexual blood stage development and underscore the potential of targeting these pathways as a therapeutic strategy against malaria
Defining terminology and outcome measures for evaluating overdose response technology:an international Delphi study
No full textIntroduction: Various novel harm reduction services leverage technology to reduce the rising number of drug poisoning deaths, particularly among those who use drugs alone. There is significant variability in terminology and outcome measures in reporting these interventions, complicating efforts to build a comprehensive knowledge base. Thus, we conducted a Delphi study to establish consensus and heterogeneity in these metrics. Methods: Panellists from three stakeholder groups (people who use drugs, virtual harm reduction service operators and academics) participated in a multi-round Delphi study. The first round included open-ended questions to propose items in three categories: terminology, demographic information and outcomes. Subsequent rounds included options from a previously conducted scoping review for consideration. Likert ratings were used to achieve consensus, with a 70% threshold. Final rounds involved ranking terminology that reached a consensus. Results: Of 23 initial participants, 14 completed the fourth survey round. ?Overdose response technology? was identified as the most appropriate term for these harm reduction technologies. This definition includes drug contamination alerts, overdose response hotlines and applications, wearable overdose detection technology and overdose detection tools. Fourteen demographic outcomes reached a consensus for data collection, including name or handle, neighbourhood, age, gender, past overdose experience, substance used, amount and route of use. Six service use outcomes were recommended: response type, service outcomes, morbidity and mortality, overdose events, responder arrival time and post-rescue care. Discussion and Conclusions: The study results are recommended to standardise terminology and guide future research and knowledge dissemination in the field, ensuring clear communication with a shared language