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Improvement of water quality for mass anopheline rearing: Dynamics of larval tray bacterial communities under different water treatments revealed by 16S ribosomal RNA amplicon sequencingBACKGROUND: Immature anophelines inhabit aquatic environments with diverse physicochemical properties and microorganisms. In insectary settings, ammonia accumulation in larval rearing trays can lead to high larval mortality. Bacterial communities in these trays may influence ammonia levels through nitrification and denitrification. While symbiotic bacteria are known to be crucial for nutrition, digestion, reproduction, and immune responses in anophelines, the microbial communities specifically associated with Anopheles coluzzii larvae have not been characterised. METHODS AND RESULTS: Building on a study examining ammonia-capturing zeolite and water changes for rearing Anopheles coluzzii, this research characterised the bacterial communities using 16S rRNA gene sequencing to identify species linked to larval survival and phenotypic quality. Functional filters were applied to identify bacteria related to ammonia nitrification and their impact on larval development. qPCR was used to validate the sequencing data for the ten most significant bacteria. Water changes significantly reduced bacterial diversity and abundance, improving adult mosquito development and quality. In contrast, untreated trays showed a higher abundance of potentially harmful bacteria, adversely affecting development. Applying zeolite increased nitrifying bacteria presence, benefiting mosquito growth while lowering toxic bacteria levels-trends confirmed by qPCR. CONCLUSIONS: This study offers insights into the bacterial communities in mosquito larval-rearing water, highlighting species that could enhance ammonia nitrification and overall rearing success.
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Strong convergence for efficient full discretization of the stochastic Allen-Cahn equation with multiplicative noiseIn this paper, we study the strong convergence of the full discretization based on a semi-implicit tamed approach in time and the finite element method with truncated noise in space for the stochastic Allen-Cahn equation driven by multiplicative noise. The proposed fully discrete scheme is efficient thanks to its low computational complexity and mean-square unconditional stability. The low regularity of the solution due to the multiplicative infinite-dimensional driving noise and the non-global Lipschitz difficulty intruduced by the cubic nonlinear drift term make the strong convergence analysis of the fully discrete solution considerably complicated. By constructing an appropriate auxiliary procedure, the full discretization error can be cleverly decomposed, and the spatio-temporal strong convergence order is successfully derived under certain weak assumptions. Numerical experiments are finally reported to validate the theoretical result.
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Automorphisms of models of set theory and extensions of NFUIn this paper we exploit the structural properties of standard and non-standard models of set theory to produce models of set theory admitting automorphisms that are well-behaved along an initial segment of their ordinals. NFU is Ronald Jensen's modification of Quine's ‘New Foundations’ Set Theory that allows non-sets (urelements) into the domain of discourse. The axioms AxCount, AxCount≤ and AxCount≥ each extend NFU by placing restrictions on the cardinality of a finite set of singletons relative to the cardinality of its union. Using the results about automorphisms of models of subsystems of set theory we separate the consistency strengths of these three extensions of NFU. More specifically, we show that NFU+AxCount proves the consistency of NFU+AxCount≤, and NFU+AxCount≤ proves the consistency of NFU+AxCount≥.
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EffUnet-SpaGen: An efficient and spatial generative approach to glaucoma detectionCurrent research in automated disease detection focuses on making algorithms "slimmer" reducing the need for large training datasets and accelerating recalibration for new data while achieving high accuracy. The development of slimmer models has become a hot research topic in medical imaging. In this work, we develop a two-phase model for glaucoma detection, identifying and exploiting a redundancy in fundus image data relating particularly to the geometry. We propose a novel algorithm for the cup and disc segmentation "EffUnet" with an efficient convolution block and combine this with an extended spatial generative approach for geometry modelling and classification, termed "SpaGen" We demonstrate the high accuracy achievable by EffUnet in detecting the optic disc and cup boundaries and show how our algorithm can be quickly trained with new data by recalibrating the EffUnet layer only. Our resulting glaucoma detection algorithm, "EffUnet-SpaGen", is optimized to significantly reduce the computational burden while at the same time surpassing the current state-of-art in glaucoma detection algorithms with AUROC 0.997 and 0.969 in the benchmark online datasets ORIGA and DRISHTI, respectively. Our algorithm also allows deformed areas of the optic rim to be displayed and investigated, providing explainability, which is crucial to successful adoption and implementation in clinical settings.
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Automatic detection of glaucoma via fundus imaging and artificial intelligence: A reviewGlaucoma is a leading cause of irreversible vision impairment globally, and cases are continuously rising worldwide. Early detection is crucial, allowing timely intervention that can prevent further visual field loss. To detect glaucoma an examination of the optic nerve head via fundus imaging can be performed, at the center of which is the assessment of the optic cup and disc boundaries. Fundus imaging is noninvasive and low-cost; however, image examination relies on subjective, time-consuming, and costly expert assessments. A timely question to ask is: "Can artificial intelligence mimic glaucoma assessments made by experts?" Specifically, can artificial intelligence automatically find the boundaries of the optic cup and disc (providing a so-called segmented fundus image) and then use the segmented image to identify glaucoma with high accuracy? We conducted a comprehensive review on artificial intelligence-enabled glaucoma detection frameworks that produce and use segmented fundus images and summarized the advantages and disadvantages of such frameworks. We identified 36 relevant papers from 2011 to 2021 and 2 main approaches: 1) logical rule-based frameworks, based on a set of rules; and 2) machine learning/statistical modeling-based frameworks. We critically evaluated the state-of-art of the 2 approaches, identified gaps in the literature and pointed at areas for future research.
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Decidable fragments of the simple theory of types with infinity and NFWe identify complete fragments of the simple theory of types with infinity (TSTI) and Quine's new foundations (NF) set theory. We show that TSTI decides every sentence φ in the language of type theory that is in one of the following forms: (A) φ = ∀x r11 ⋯ ∀xrkk ∃ys11 ⋯ ∃ys11 θ where the superscripts denote the types of the variables, s1 > ⋯ > s1, and θ is quantifier-free, (B) φ = ∀x r11 ⋯ ∀xrkk ∃ys11 ⋯ ∃ys11 θ where the superscripts denote the types of the variables and θ is quantifier-free. This shows that NF decides every stratified sentence φ in the language of set theory that is in one of the following forms: (A′) φ = ∀x1 ⋯ ∀xk ∃y1 ⋯ ∃yl θ where θ is quantifier-free and φ admits a stratification that assigns distinct values to all of the variables y1,⋯, yl, (B′) φ = ∀x1 ⋯ ∀xk ∃y1 ⋯ ∃yl θ where θ is quantifier-free and <p admits a stratification that assigns the same value to all of the variables y1,⋯, yl.
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On the relative strengths of fragments of collectionLet M be the basic set theory that consists of the axioms of extensionality, emptyset, pair, union, powerset, infinity, transitive containment, Δ0-separation and set foundation. This paper studies the relative strength of set theories obtained by adding fragments of the set-theoretic collection scheme to M. We focus on two common parameterisations of the collection: -collection, which is the usual collection scheme restricted to -formulae, and strong -collection, which is equivalent to -collection plus -separation. The main result of this paper shows that for all , 1. M + proves that there exists a transitive model of Zermelo Set Theory plus -collection, 2. the theory M + is -conservative over the theory M + strong . It is also shown that (2) holds for when the Axiom of Choice is included in the base theory. The final section indicates how the proofs of (1) and (2) can be modified to obtain analogues of these results for theories obtained by adding fragments of collection to a base theory (Kripke-Platek Set Theory with Infinity plus V=L) that does not include the powerset axiom.
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Initial self-embeddings of models of set theoryBy a classical theorem of Harvey Friedman (1973), every countable nonstandard model MM of a sufficiently strong fragment of ZF has a proper rank-initial self-embedding j, i.e., j is a self-embedding of MM such that j[M]⊊Mj[M]⊊M , and the ordinal rank of each member of j[M]j[M] is less than the ordinal rank of each element of M∖j[M]M∖j[M] . Here, we investigate the larger family of proper initial-embeddings j of models MM of fragments of set theory, where the image of j is a transitive submodel of MM . Our results include the following three theorems. In what follows, ZF−ZF− is ZFZF without the power set axiom; WOWO is the axiom stating that every set can be well-ordered; WF(M)WF(M) is the well-founded part of MM ; and Π1∞-DCαΠ∞1-DCα is the full scheme of dependent choice of length αα . Theorem A. There is an ωω -standard countable nonstandard model MM of ZF−+WOZF−+WO that carries no initial self-embedding j:M⟶Mj:M⟶M other than the identity embedding. Theorem B. Every countable ωω -nonstandard model MM of ZF ZF is isomorphic to a transitive submodel of the hereditarily countable sets of its own constructible universe LMLM . Theorem C. The following three conditions are equivalent for a countable nonstandard model MM of ZF−+WO+∀α Π1∞-DCαZF−+WO+∀α Π∞1-DCα . 1. (I) There is a cardinal in MM that is a strict upper bound for the cardinality of each member of WF(M)WF(M) . 2. (II) WF(M)WF(M) satisfies the powerset axiom. 3. (III) For all n∈ωn∈ω and for all b∈Mb∈M , there exists a proper initial self-embedding j:M⟶Mj:M⟶M such that b∈rng(j)b∈rng(j) and j[M]≺nMj[M]≺nM .
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End extending models of set theory via power admissible coversMotivated by problems involving end extensions of models of set theory, we develop the rudiments of the power admissible cover construction (over ill-founded models of set theory), an extension of the machinery of admissible covers invented by Barwise as a versatile tool for generalising model-theoretic results about countable well-founded models of set theory to countable ill-founded ones. Our development of the power admissible machinery allows us to obtain new results concerning powerset-preserving end extensions and rank extensions of countable models of subsystems of ZFC . The canonical extension KP P of Kripke-Platek set theory KP plays a key role in our work; one of our results refines a theorem of Rathjen by showing that Σ 1 P -Foundation is provable in KP P (without invoking the axiom of choice).
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On the strength of a weak variant of the axiom of countingIn this paper NFU-AC is used to denote Jensen's modification of Quine's ‘new foundations’ set theory (NF) fortified with a type-level pairing function but without the axiom of choice. The axiom AxCount>_ is the variant of the axiom of counting which asserts that no finite set is smaller than its own set of singletons. This paper shows that NFU-AC + AxCount>_ proves the consistency of the simple theory of types with infinity (TSTI). This result implies that NF + AxCount>_ proves that consistency of TSTI, and that NFU-AC + AxCount>_ proves the consistency of NFU-AC.
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Largest initial segments pointwise fixed by automorphisms of models of set theoryGiven a model M of set theory, and a nontrivial automorphism j of M, let Ifix(j) be the submodel of M whose universe consists of elements m of M such that j(x)=x for every x in the transitive closure of m (where the transitive closure of m is computed within M). Here we study the class C of structures of the form Ifix(j), where the ambient model M satisfies a frugal yet robust fragment of ZFC known as MOST, and j(m)=m whenever m is a finite ordinal in the sense of M. Our main achievement is the calculation of the theory of C as precisely MOST+Δ0P Collection. The following theorems encapsulate our principal results: Theorem A. Every structure inC satisfies MOST+Δ0P Collection. Theorem B. Each of the following three conditions is sufficient for a countable structure (a) N is a transitive model of MOST+Δ0P Collection. (b) N is a recursively saturated model of MOST+Δ0P Collection. (c) N is a model of ZFC. Theorem C. Suppose M is a countable recursively saturated model of ZFC and I is a proper initial segment of OrdM that is closed under exponentiation and contains ωM. There is a group embedding j⟼j from Aut(Q) into Aut(M) such that I is the longest initial segment of OrdM that is pointwise fixed by jˇ for every nontrivial j∈Aut(Q). In Theorem C, Aut(X) is the group of automorphisms of the structure X, and Q is the ordered set of rationals.
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Feferman’s forays into the foundations of category theoryThis paper is primarily concerned with assessing a set-theoretical system, S*, for the foundations of category theory suggested by Solomon Feferman. S* is an extension of NFU, and may be seen as an attempt to accommodate unrestricted categories such as the category of all groups (without any small/large restrictions), while still obtaining the benefits of ZFC on part of the domain. A substantial part of the paper is devoted to establishing an improved upper bound on the consistency strength of S*. The assessment of S* as a foundation of category theory is framed by the following general desiderata (R) and (S). (R) asks for the unrestricted existence of the category of all groups, the category of all categories, the category of all functors between two categories, etc., along with natural implementability of ordinary mathematics and category theory. (S) asks for a certain relative distinction between large and small sets, and the requirement that they both enjoy the full benefits of the ZFC axioms. S* satisfies (R) simply because it is an extension of NFU. By means of a recursive construction utilizing the notion of strongly cantorian sets, we argue that it also satisfies (S). Moreover, this construction yields a lower bound on the consistency strength of S*. We also exhibit a basic positive result for category theory internal to NFU that provides motivation for studying NFU-based foundations of category theory.
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Iterated ultrapowers for the massesWe present a novel, perspicuous framework for building iterated ultrapowers. Furthermore, our framework naturally lends itself to the construction of a certain type of order indiscernibles, here dubbed tight indiscernibles, which are shown to provide smooth proofs of several results in general model theory.
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Relationships between structure and properties in commercial lead zirconate titanate (PZT) piezoceramicsLead zirconate titanate (PZT) ceramics are the most widely used commercial piezoelectric ceramics. However, the relationships between structure and properties are still not completely clarified. In this work, a broad investigation is carried out on commercial PZT 5A, 5H and 4D ceramics. X-ray diffraction revealed that these compounds mainly contain a mixture of P4mm and C1m1 phases at room temperature, and poling induces an increased unit cell distortion in both phases and a higher content of the monoclinic phase. In the poled samples, the Curie point shifts towards lower temperatures, contradicting the Abrahams-Kurtz-Jamieson (AKJ) relation for distorted displacive ferroelectrics. The discordance in the phase transition behavior can be attributed to the decreased domain wall density in the PZT systems. Furthermore, the observed increase of the dielectric permittivity from radiofrequency to the THz range is explained by the increase of the ferroelectric distortion associated with the field-induced transitions and decreased domain wall density. A parameter ψ was introduced to characterize the asymmetry of ferroelectric hysteresis loops. The higher ψ value of the hard PZT 4D ceramic compared to that of soft PZT 5A and 5H is attributed to the pinning effect of oxygen vacancies on domain walls.
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Does measuring social attention lead to changes in behavior? A preliminary investigation into the implications of attention bias trials on behavior in Rhesus MacaquesA welfare assessment tool in development must satisfy several criteria before it is considered ready for general use. Some tools that meet many of these criteria have been criticized for their negative effect on welfare. We conducted a preliminary assessment of the impact of attention bias (AB) trials using threat-neutral conspecific face pairs followed by presumed neutral-positive filler stimuli on the behavior of 21 rhesus macaques (Macaca mulatta; 15 female). Behavioral observations were conducted following AB trials and repeated two weeks later when no AB trials had occurred (no trial: NT). The association between observation period and behavior was assessed using linear mixed-effects models in R. Trials did not impact any observed behavior except for fear, which was displayed by five monkeys over six trials (four NT). For this sample, there was a significant reduction in fear behavior following AB trials. We, therefore, found no evidence suggesting that AB trials negatively affect behaviour. AB protocols may be suitable for continued development for primate welfare assessment and we encourage researchers to include assessing test impact on welfare in their AB protocols.
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The recent development of protection coordination schemes based on inverse of AC microgrid: A reviewIntegration of distributed generation systems and diversity of microgrid operations led to a change in the structure of the power system. Due to this conversion, new challenges have arisen when employing traditional overcurrent protection schemes. As a consequence, non‐classical protection schemes have attracted significant attention in the last few years. Engineers and scholars have proposed different non‐standard methods to increase the power protection system and ensure the highly selectivity performance. Although the non‐standard characteristics and their requirements, in general, have been outlined and analyzed in the available literature, protection coordination based on voltage current–time inverse, as a branch of non‐standard optimization methods, has not yet been thoroughly discussed, compared, or debated in detail. To close this gap, this review introduces a broad overview of recent research and developments of the voltage current–time inverse based protection coordination. Focuses on assessing the potential advantages and disadvantages of related studies and provide a classification and analysis of these studies. The future trends and some recommendations have been included in this review for improving fault detection sensitivity and coordination reliability.
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Evaluating the severity of trust to Identity-Management-as-a-ServiceThe benefits of a c loud service have been well documented as reduced cost in both staff and computing infrastructure, rapid deployment, and scalabilit y and location independence. Despite all these benefits, Identity-management-as- a-Service's (IdMaaS) is struggling to gain a market presence due to an array of factors one of which is trust. In IdMaaS, trust may either be borne within the relationships amongst the actors (relying party, identity manager, identity owner, or end user) or may be actor specific. This paper will focus on trust between the identity owner and the identi ty manager within the context of third party identity management. A great effort in identifying trust issues by other researchers is acknowledged, however they did not go to the ext ent of measuring th e severity of t rust specifically related to I dMaaS. Our research shows that availability of the identity management system and security of identities are more critical concerns when compared to the cost of managing identities and fear of vendor lock-in. Above all, the research revealed that trust in IdMaaS is less than 40% at a 95% level of con fidence. Establishing the severity of tru st and its trusting factors is a more valuable input to the refinement of the IdMaaS approach. The success of IdMaaS will add to the domain of anything-as-a-service (XaaS) at the same time opening up an additional entrepreneurial avenue.
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A unique ternary Ce(III)-quercetin-phenanthroline assembly with antioxidant and anti-inflammatory propertiesQuercetin is one of the most bioactive and common dietary flavonoids, with a significant repertoire of biological and pharmacological properties. The biological activity of quercetin, however, is influenced by its limited solubility and bioavailability. Driven by the need to enhance quercetin bioavailability and bioactivity through metal ion complexation, synthetic efforts led to a unique ternary Ce(III)-quercetin-(1,10-phenanthroline) ( 1 ) compound. Physicochemical characterization (elemental analysis, FT-IR, Thermogravimetric analysis (TGA), UV-Visible, NMR, Electron Spray Ionization-Mass Spectrometry (ESI-MS), Fluorescence, X-rays) revealed its solid-state and solution properties, with significant information emanating from the coordination sphere composition of Ce(III). The experimental data justified further entry of 1 in biological studies involving toxicity, ROS-suppressing potential, cell metabolism inhibition in Saccharomyces cerevisiae (S. cerevisiae) cultures, and plasmid DNA degradation. DFT calculations revealed its electronic structure profile, with in silico studies showing binding to DNA, DNA gyrase, and glutathione S-transferase, thus providing useful complementary insight into the elucidation of the mechanism of action of 1 at the molecular level and interpretation of its bio-activity. The collective work projects the importance of physicochemically supported bio-activity profile of well-defined Ce(III)-flavonoid compounds, thereby justifying focused pursuit of new hybrid metal-organic materials, effectively enhancing the role of naturally-occurring flavonoids in physiology and disease.
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L1 scheme for semilinear stochastic subdiffusion with integrated fractional Gaussian noiseThis paper considers a numerical method for solving the stochastic semilinear subdiffusion equation which is driven by integrated fractional Gaussian noise and the Hurst parameter H∈(1/2,1). The finite element method is employed for spatial discretization, while the L1 scheme and Lubich’s first-order convolution quadrature formula are used to approximate the Caputo time-fractional derivative of order α∈(0,1) and the Riemann–Liouville time-fractional integral of order γ∈(0,1), respectively. Using the semigroup approach, we establish the temporal and spatial regularity of the mild solution to the problem. The fully discrete solution is expressed as a convolution of a piecewise constant function with the inverse Laplace transform of a resolvent-related function. Based on the Laplace transform method and resolvent estimates, we prove that the proposed numerical scheme has the optimal convergence order O(τmin{H+α+γ−1−ε,α}),ε>0. Numerical experiments are presented to validate these theoretical convergence orders and demonstrate the effectiveness of this method.
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IoT embedded software manipulationThe Internet of Things (IoT) has raised cybersecurity and privacy issues, notably about altering embedded software. This poster investigates the feasibility of using Read-Only Memory (ROM) at a low level to modify IoT devices while remaining undetectable to users and security systems. The study explores the vulnerabilities in embedded code and firmware, which are frequently proprietary and inaccessible, making them challenging to safeguard efficiently. The methodology uses a black-box forensic technique to acquire software, identify functions, and create test cases to assess potential alterations. The findings aim to contribute to a better understanding of IoT security concerns, emphasising the importance of upgraded firmware protection methods. This research highlights the challenges of detecting low-level attacks on IoT devices and provides insights into improving embedded system security.
