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Article
Medicine and Pharmacology
Neuroscience and Neurology

Leonardo Lopez-Ortiz

,

Cristhian K. Valencia-Marin

,

Julian Gil-Gonzalez

,

Paula M. Herrera-Gómez

,

David Cárdenas-Peña

Abstract: Electroencephalography (EEG) provides a non-invasive alternative for supporting Attention-Deficit/Hyperactivity Disorder (ADHD) assessment, but existing classification pipelines often depend on handcrafted descriptors, segment-wise decisions, or deep neural architectures whose interpretability and subject-level generalization remain limited. This work introduces Hidden Markov Model-Induced Stationary RKHS Distance Learning (HIS), a probabilistic-kernel framework for interpretable EEG-based support for the diagnosis of ADHD. In the proposed approach, each subject is represented by a Hidden Markov Model with Gaussian-mixture emissions, trained on frontal EEG recordings. Rather than vectorizing the learned parameters, each HMM is mapped to its induced stationary observation distribution, which is then embedded into a Reproducing Kernel Hilbert Space. Pairwise subject dissimilarities are computed through a closed-form Hilbert embedding distance between stationary Gaussian mixture distributions and used by precomputed-kernel classifiers. The method was evaluated on a controlled synthetic EEG benchmark and on a public pediatric ADHD EEG dataset recorded during a visual attention task. The proposed HIS distance was compared against the Probability Product Kernel, a finite-horizon HMM similarity baseline. On synthetic EEG, HIS achieved 95.0% held-out test accuracy and consistently outperformed the baseline across classifiers. On the real EEG dataset, the best configuration used a compact HMM topology and KNN classification, reaching 95.8% held-out test accuracy at the subject level. Qualitative t-SNE analyses further showed that HIS induces more discriminative local subject neighborhoods than the baseline kernel, while avoiding segment-level sample inflation. These results suggest that stationary RKHS embeddings of subject-specific HMMs provide a competitive, leakage-aware, and interpretable framework for modeling variable-length EEG recordings in ADHD classification.

Article
Medicine and Pharmacology
Dentistry and Oral Surgery

Pantelie Nicolcescu

,

Aurel Nechita

,

Mădălina-Nicoleta Matei

,

Ciprian-Adrian Dinu

,

Anamaria Ciubara

,

Gabriel Valeriu Popa

,

Razvan Mercut

,

Adrian Carciumaru

,

Maria Mercut

Abstract: Background: Persistent challenges in healthcare infection control, particularly the need for rapid hand hygiene during continuous patient care, highlight limitations of current personal protective equipment (PPE). We developed a lightweight face shield integrating a disinfectant reservoir to enable immediate point-of-care hand sanitisation. Methods: A dual-function system was designed comprising a polyethylene terephthalate glycol (PETG) visor (23 × 23 cm, 0.20 mm) and a modular disinfectant reservoir (25–100 mL). Components were fabricated using CAD, 3D printing, and PETG forming. The reservoir features a touch-activated, self-sealing valve delivering approximately 3 mL per activation. Benchtop testing assessed dosing consistency, leak-tightness, attachment security, material compatibility with alcohol-based disinfectants, and durability. Results: The visor weighed 13.4 g, with total system mass of 103.4 g (empty) and 203.4 g (maximum fill). Cervical torque increased from 0.084 to 0.282 N·m, supporting continuous wear for 60–90 minutes. Testing confirmed consistent dosing, reliable resealing, leak-free performance, and PETG stability after disinfectant exposure. Conclusions: This dual-function visor integrates facial protection with immediate hand sanitisation, addressing critical infection-control challenges in dentistry. Its low cost, reusability, and modular design support chairside use and mobile dentistry, while enabling future integration of wearable sensors.

Article
Computer Science and Mathematics
Applied Mathematics

Dalila Remaoun Bourega

,

Djahida Hiber

Abstract: This work investigates the exact boundary controllability of the heat equation posed in a spherical domain, using the method of moments. Starting from the spectral decomposition of the radial Laplacian in the weighted space \( L^2_{r^2}(0,R) \), we derive a sequence of moment equations whose solvability is established via biorthogonal sequences, following the Fattorini–Russell theory. The resulting control function is expressed as a series expansion whose convergence in \( L^2(0,t_f) \) is rigorously proved for any initial temperature distribution in \( L^2_{r^2}(0,R) \) and any final time tf exceeding a minimal threshold. The numerical implementation employs linear finite elements in space and the implicit Euler scheme in time. The accuracy of the solver is rigorously verified through the Method of Manufactured Solutions (MMS), confirming optimal convergence rates: second-order in space and first-order in time. Numerical experiments show that the computed control drives the temperature to zero with a residual norm of 1.96×10−4, consistent with the spatial discretization error. A comparative analysis with two alternative approaches—the Hilbert Uniqueness Method (HUM) and gradient-based optimization—demonstrates that the proposed moment-based strategy achieves an 18.9% reduction in total control energy relative to HUM, making it particularly attractive for energy-constrained thermal control applications.

Article
Public Health and Healthcare
Public Health and Health Services

Adriana Arevalo-Jamaica

,

Yussely Tatiana Cobos-Leon

,

Jhindy Tatiana Pérez-Lozada

,

Beatriz Elena De arco-Rodriguez

,

Dioselina Peláez-Carvajal

,

Claudia Marcela Castro-Osorio

,

Luisa Fernanda Vasquez-Chavez

,

Mayra Alejandra Vargas-Rojas

,

Vivian Vanesa Rubio

,

Sonia Lorena Valencia-Claros

+4 authors

Abstract: Acute diarrheal disease (ADD) caused by parasites and TB represent a significant public health burden worldwide and in Colombia, particularly affecting indigenous populations who are at high risk of contracting these diseases due to the social, environmental, and cultural conditions in which they live. Materials: Fifteen Wayuu indigenous communities in four areas of Manaure, in La Guajira, were subject to intervention; with prior informed consent, environmental samples and samples from individuals with clinical symptoms were collected. A total of 156 samples of human and animal feces, soil, and sediment from drinking water were analyzed for microscopic using the Kato–Katz and formalin–ether concentration techniques, 109 samples were analyzed by qPCR for the detection of helminths and 23 for metatranscriptomics targeting protozoan parasites and helminths. Additionally, 36 sputum samples from patients with respiratory symptoms were tested using Xpert/MTB Rif, and 37 milk samples were tested for M. bovis. Results: Among the samples tested for tuberculosis, a positivity rate of 8.3% was found, in all cases with sensitivity to rifampicin; M. bovis was not found in animal milk. Microscopic analysis of human samples revealed pathogenic parasites, the most common being Blastocystis spp. and the Entamoeba hystolitica/Entamoeba dispar complexeach with 38.8% (n=38), Giardia spp. with 19.4%, Hymenolepis nanaand Trichuris trichiura each with 5.1%. Commensal parasites were also identified as indicator of poor sanitary conditions. Co-infection with intestinal parasites was common in humans at 60.2%. In microscopic analysis of animals fecal samples, revealed a high incidence of Uncinaria spp. with 58.3%, amoebas 16.7% and Giardia 8.3%; this latter is also found in soil. Metatranscriptomics showed a high frequency of intestinal parasites in fecal samples (90.9%), with Blastocystis spp. being the most frequent (81.8%) with notable intra-species diversity, followed by Entamoeba histolytica (54.5%) and Giardia duodenalis (31.8%), and detected free-living amoebae in community water sources, highlighting potential health risks associated with exposure to untreated water in low-sanitation settings. Conclusions: The Wayuu communities studied show a significant burden of tuberculosis and intestinal parasitic infections, likely associated with poor sanitary conditions and environmental factors that facilitate their transmission. Although TB prevalence was moderate, with no evidence of rifampicin resistance or the circulation of M. bovis in milk, the high prevalence of intestinal parasites, including co-infections and their detection in humans, animals, and the environment suggest active transmission in the region. These findings highlight the need to implement comprehensive interventions in water, sanitation, and hygiene, along with surveillance and health education strategies with an intercultural approach, aimed at improving the conditions of these vulnerable populations.

Article
Engineering
Architecture, Building and Construction

Andrzej Szymon Borkowski

,

Paulina Jarema

,

Anatolii Smoliar

Abstract: Building Information Modeling (BIM) represents a building as a static snapshot of the model’s state. The IFC standard does not define a formal mechanism that would link the same physical element across successive phases of a building’s life cycle. Design, construction, and operation are recorded in separate IFC files, and the same element is assigned different GUIDs in each. The result is fragmentation of the element’s identity, loss of the history of property changes, and the inability to formulate cross-phase queries. This paper proposes the BIM-Phase ontology, based on the fundamental DOLCE ontology, which solves this problem by introducing a distinction between a building element as an endurant and its life cycle phases as perdurants. The ontology comprises nine classes, six object relations, and six axioms expressed in OWL 2 DL. Phase properties and relations are represented using a reification pattern, which maintains full compatibility with the expressiveness of OWL 2 DL. The ontology was validated using the example of a single-family residential building developed in Autodesk Revit. Three structural elements (external wall, floor slab, column) were tracked across three phases of the life cycle. Eight competency questions covering scalar, constitutional, and mereological changes were defined and mapped to ontology constructs, confirming that BIM-Phase enables the recording of changes and the formulation of cross-phase queries that are impossible in classic IFC.

Article
Medicine and Pharmacology
Immunology and Allergy

Polona Žigon

,

Katja Lakota

,

Katarina Ogrinc

,

Petra Bogovič

,

Franc Strle

Abstract: Objectives: Borrelia burgdorferi sensu lato, a spirochete bacterium responsible for Lyme borreliosis - the most common tick-borne infection in North America and Europe - can trigger the production of antiphospholipid antibodies. These antibodies target host lipids such as cardiolipin (CL), phosphatidic acid (PA), phosphatidylcholine (PC), and phosphatidylserine (PS), which the spirochete incorporates into its membrane from the surrounding environment. Although antiphospholipid antibodies are typically associated with antiphospholipid syndrome (APS), they may also arise during infections, including Lyme borreliosis. This study aimed to develop and optimize several enzyme-linked immunosorbent assays (ELISAs) for measuring various antiphospholipid antibodies in patients with Lyme borreliosis. Methods: Thirty patients diagnosed with Lyme borreliosis were enrolled: ten with solitary erythema migrans (EM), ten with multiple EM (MEM), and ten with late manifestations known as acrodermatitis chronica atrophicans (ACA). Forty healthy blood donors served as controls. Four distinct antiphospholipid antibody ELISAs were developed, each using a different phospholipid coating: CL, PA, PC, and PS. Serum of APS patient was used as a positive control and for standard curve generation. Results: All four ELISAs were successfully established and demonstrated good measurement precision. Significant differences in antiphospholipid antibody levels and positivity rates were observed between Lyme borreliosis patients and healthy blood donors. Notably, levels of antibodies directed against PA (aPA), PC (aPC), and PS (aPS), both IgG and IgM, were significantly higher in patients with late Lyme borreliosis, manifested as ACA, compared to healthy blood donors. In contrast, anti-CL (aCL) levels did not differ significantly between groups. Patients with ACA also showed the highest frequency of multiple antiphospholipid antibody positivity, with 7 of 10 patients testing positive for three or more antiphospholipid antibodies. Conclusions: Accurate and precise in-house ELISAs for the detection of aCL, aPA, aPC, and aPS using APS sera as standard material were developed and validated for the analysis of samples of patients with Lyme borreliosis. Our data suggest that antiphospholipid antibody levels—specifically aPA, aPC, and aPS—differ across clinical manifestations of Lyme borreliosis, with the greatest increases observed in patients with ACA.

Review
Environmental and Earth Sciences
Geography

Garry Rogers

Abstract: Artificial intelligence (AI) is a human-built component of the technosphere, not an intelligence outside Earth-system limits. As AI systems scale, they increasingly shape the decisions, infrastructures, and capital flows through which human activity damages the biosphere. Dominant deployed foundation-model alignment methods, including reinforcement learning from human feedback (RLHF) and constitutional AI, treat human preferences as the primary alignment target while leaving biosphere integrity as context, externality, or secondary constraint. That framing is structurally incomplete. Human welfare, technological continuity, and AI operation all depend on biosphere function. Three convergent literatures support a corrective framework: planetary-boundary analysis showing seven of nine boundaries transgressed; energy-system analysis showing rapid and infrastructure-constrained data-center growth during the 2025-2030 buildout; and collective-action analysis showing that voluntary ecological restraint is unstable under competitive pressure. These literatures imply a design conclusion: ecological constraints must be formalized as hard inference-time refusal rules and reinforced through reward design. This paper presents Biosphere Sentinel as a reference architecture for reducing human and technospheric impacts on the biosphere through refusal rules, an eight-domain reward landscape, carbon-lock-in diagnostics, and a proposed Trophic Integrity Index pathway.

Article
Medicine and Pharmacology
Cardiac and Cardiovascular Systems

Yuetong Leona Ding

,

Dominika Bernath-Nagy

,

Chiara Heß

,

Florian Leuschner

,

Hugo Albert Katus

,

Norbert Frey

,

Jona Benjamin Krohn

,

Evangelos Giannitsis

Abstract: Background/Objectives: High-sensitivity cardiac troponin (hs-cTn) assays are used in routine diagnostics to detect myocardial injury. However, a fraction of circulating cardiac troponin T (cTnT) enclosed within extracellular vesicles (EVs) goes widely undetected. This study introduces a combined lysis- and sonication-based protocol to release and quantify EV-bound cTnT in a time-efficient manner using a state-of-the-art hs-cTnT immunoassay. Methods: Plasma samples from patients with non-ST-segment elevation myocardial infarction (NSTEMI), unstable angina, pulmonary embolism, decompensated aortic stenosis, atrial fibrillation, myocarditis, and healthy controls were treated with lysis buffer and subsequently sonicated. Treated and untreated samples were assessed and compared to a conventional EV isolation method. Results: Following combined lysis and sonication, cTnT levels were significantly higher compared to native, unprocessed samples across all cohorts. Median increase post-processing ranged from 10% in decompensated aortic stenosis to 34% in healthy controls. In NSTEMI, EV-bound cTnT accounted for 15% of plasma cTnT and remained stable over 72 hours. EV cTnT/plasma cTnT ratios were comparable between the combined lysis and sonication approach and the conventional EV isolation method. Processing time prior to cTnT measurement was reduced from approximately 2.5 hours to approximately 10 minutes using combined lysis and sonication compared to the established EV isolation method. Conclusions: Our method allows for rapid liberation of a previously inaccessible EV-bound fraction of cTnT without the need for time-consuming and resource-intensive EV isolation workflows. The resulting total cTnT signatures indicate differential cTnT compartmentation depending on the underlying myocardial pathophysiology, enabling early differentiation of the mechanisms underlying troponin elevation. This approach is readily implementable alongside standard hs-cTnT testing at minimal additional time expense and may improve diagnostic sensitivity and specificity in acute clinical settings.

Article
Biology and Life Sciences
Animal Science, Veterinary Science and Zoology

Ali Kiani

,

German Jurgens

,

Gemma Gonzalez Ortiz

,

Carrie L. Walk

,

Teemu Rinttilä

Abstract: The impact of dietary inert digestibility markers on gut microbiota and intestinal fermentation remains poorly understood. This study investigated the effects of titanium dioxide (TiO₂) supplementation at 4 kg/ton feed, representing a typical dose used in animal nutrition studies, on fermentation dynamics and microbial composition in broiler chickens using combined ex vivo and in vivo approaches. Ex vivo fermentations were conducted using ileal and caecal microbiota and substrates collected from 32-day-old broiler chickens, with direct TiO₂ supplementation, with gas production and volatile fatty acid (VFA) profiles as main measurements. In parallel, 392 broiler chickens were fed diets with or without TiO₂ for 32 days, and ileal and caecal digesta were analysed for fermentation end-products and microbial composition using shotgun metagenomic sequencing. A second ex vivo experiment was performed using microbiota adapted to dietary TiO₂. In the first ex vivo model, TiO₂ reduced gas production and acetic acid concentration in the ileum (p < 0.05), whereas in the caecum it increased gas production, total eubacterial counts, and branched-chain fatty acids (BCFA) (p < 0.05). In vivo, TiO₂ did not affect growth performance or organ development but significantly increased isobutyric acid and total BCFA concentrations in the caecum (p < 0.05). Metagenomic analysis revealed increased caecal alpha diversity (Shannon index) and enrichment of taxa associated with amino acid metabolism, including Massilicoli timonensis, Blautia merdavium, Rubneribacter badeniensis, and Mediterraneibacter caccavium. The second ex vivo experiment showed similar trends, with increased gas and BCFA production. Collectively, these findings indicate that TiO₂ can modulate intestinal fermentation and microbial composition in a segment-specific manner, suggesting that dietary markers may not be biologically inert.

Article
Engineering
Industrial and Manufacturing Engineering

Francisco Yuraszeck

,

Frank Werner

,

Daniel Rossit

Abstract: The Job Shop Scheduling Problem (JSSP) is a paradigmatic and strongly NP-hard combinatorial optimisation problem that underpins production planning in modern manufacturing systems, and constraint programming (CP) has become one of the leading methodologies for tackling it. However, comparative studies of CP solvers for the JSSP have so far been restricted to a single benchmark family, a single instance-size range, or a single hardware setting, which limits the practical guidance they offer to both researchers and practitioners. This paper presents a controlled empirical evaluation of four state-of-the-art CP solvers—IBM ILOG CP Optimizer, Google OR-Tools (CP-SAT), Hexaly, and OptalCP—on the makespan-minimisation JSSP. The four engines are run with default parameters and a uniform 600-second wall-clock time budget on 332 instances drawn from nine canonical benchmark families (Fisher–Thompson, Lawrence, Adams–Balas–Zawack, Applegate–Cook, Yamada–Nakano, Storer–Wu–Vaccari, Taillard, Demirkol–Mehta–Uzsoy, and Da Col–Teppan), spanning sizes from 6 × 5 up to 1000 × 1000 operations. OptalCP emerges as the most robust engine overall, certifying optimality on 57.5% of the instances with the smallest average optimality gap (3.55%), while Hexaly dominates on industrial-scale problems and produces the bulk of 31 new best-known upper bounds and one new best-known lower bound reported here. Solver competitiveness depends sharply on instance size and on the n/m ratio, with square instances confirmed as the hardest case. These findings support an instance-aware approach to CP solver selection in industrial scheduling.

Article
Computer Science and Mathematics
Data Structures, Algorithms and Complexity

Frank Vega

Abstract: We propose a framework that isolates a precise complexity-theoretic bottleneck between counting complexity and the Birch--Swinnerton-Dyer conjecture (BSD) via Tunnell's theorem. The framework rests on two number-theoretic conjectures: a \emph{Reduction Conjecture} asserting the existence of a polynomial-time reduction from any \#P-complete problem to the counting of integer representations $D_n = \#\{(x,y,z) : n = 8x^2 + 2y^2 + 16z^2\}$ (with counts preserved up to a polynomial factor), and a \emph{Solution Density Conjecture} asserting that the values $\{D_n : n \text{ even square-free congruent}\}$ are sufficiently densely distributed (within the Eichler--Deligne ceiling $D_n = O(n^{1/2+\varepsilon})$) to support iterated polynomial descent. We do \emph{not} claim that $\text{P} = \text{NP}$ implies $\#\text{P} = \text{FP}$ (the natural binary-search route fails because the threshold predicate $[\#I \geq k]$ is PP-complete, not in NP, and PP is not known to collapse under $\text{P} = \text{NP}$). Instead, we prove a structural equivalence: under the two conjectures, BSD, and $\text{P} = \text{NP}$, $\#\text{P} \subseteq \text{FP}$ if and only if the specific family TunnellCount $:= \{n \mapsto D_n\}$ is in FP. The framework thus does not resolve the $\#\text{P} \stackrel{?}{=} \text{FP}$ question; it converts it into a concrete, falsifiable arithmetic question about the polynomial-time tractability of representation counts on one specific ternary quadratic form. We identify three concrete open problems---parsimony in Matiyasevich representations, the distribution of weight-$3/2$ Fourier coefficients via Waldspurger's formula, and the FP-tractability of $D_n$ itself---whose resolution would substantiate or refute the framework.

Review
Medicine and Pharmacology
Immunology and Allergy

Margherita Sisto

,

Sabrina Lisi

Abstract: Inflammasomes arise from complex protein assembly mechanisms and play a fundamental role in managing inflammation and the innate immune response. The molecules that trigger inflammasome assembly and activation are molecules derived from pathogens or DNA fragments released following cellular damage. The phenomena resulting from inflammasome activation range from the activation of caspases, such as caspase-1, to the secretion of pro-inflammatory cytokines, to cellular death by apoptosis or pyroptosis. Various pathologies have been linked to aberrant inflammasome activation, including several autoimmune diseases, leading scientists to direct experiments toward identifying the mechanisms responsible for aberrant inflammasome activation to develop new therapeutic strategies. In this review, we summarize the assembly mechanisms and involvement of two specific inflammasomes, NLRP3 and AIM2, in the autoimmune disease Sjögren's syndrome (SjD); NLRP3 and AIM2 aberrant activations appear to be involved in the exacerbation of inflammation, which becomes chronic, leading to dry mouth and dry eye and to an increased risk of developing B-cell non-Hodgkin's lymphoma in these patients. Understanding how different inflammasomes contribute to the pathogenesis of SjD could be fundamental to understanding the complex molecular mechanisms underlying this disease.

Article
Computer Science and Mathematics
Artificial Intelligence and Machine Learning

Istiaque Bhuiyan

,

Tanvir Bhuiyan

Abstract: Phishing detection models often report strong benchmark performance, yet their reliability under realistic deployment conditions remains uncertain. This study examines this problem by investigating three failure modes of cross-dataset phishing email detection: corpus generalisation failure, asymmetric prevalence-shift failure, and artifact-driven spurious learning. Using six public email corpora, CEAS_08, Enron, Ling, Nazario, Nigerian Fraud, and SpamAssassin, the study evaluates Term Frequency (TF) and Inverse Document Frequency (IDF)-based Logistic Regression and Linear Support Vector Classifier (SVC) models across pooled baseline testing, single-corpus cross-dataset transfer, leave-one-corpus-out pooled training, prevalence-shift simulation, training-prevalence manipulation, dataset-identification analysis, top-feature inspection, artifact-removal ablation, and targeted artifact masking. The findings show that single-corpus models are unstable under cross-dataset transfer, with F1-scores varying substantially across source–target combinations. In contrast, leave-one-corpus-out pooled training improves robustness, with Logistic Regression achieving sustained F1-scores between 0.8201 and 0.8994, and Linear SVC achieving F1-scores between 0.7607 and 0.8910 across unseen corpora. Prevalence-shift experiments reveal that failure is asymmetric and threshold-dependent. High-prevalence-trained models maintain high recall under fixed thresholds but suffer sharp recall degradation when operational alert-budget constraints are imposed. Conversely, low-prevalence-trained models become overly conservative in high-threat environments, producing high precision but substantially lower recall and poorer calibration. Artifact analyses further show that source corpus identity is highly learnable, with dataset-identification accuracy reaching 0.9722 for Logistic Regression and 0.9806 for Linear SVC. Top-feature and masking analyses indicate that models rely partly on corpus markers, date tokens, URL/domain terms, headers, and other artifact-like features rather than only general phishing indicators. The study contributes a deployment-aware and adversary-aware evaluation framework for phishing detection. It shows that benchmark accuracy alone is insufficient for assessing real-world robustness and that reliable phishing detection requires cross-corpus validation, prevalence-aware thresholding, and systematic testing for artifact-driven spurious learning.

Review
Engineering
Architecture, Building and Construction

Temiloluwa Grace Ewulo

Abstract: Earth blocks are attractive for low-cost housing because they use local soil, require less firing energy, and can provide good thermal mass, but their adoption in humid tropical regions is limited by moisture sensitivity. This review examines how agricultural waste ash stabilizers, with emphasis on palm kernel shell ash and related pozzolanic residues, influence moisture durability, dry/wet compressive strength behavior, and practical suitability of earth blocks for affordable housing. The paper synthesizes evidence from compressed earth block literature, pozzolanic material standards, and studies on ash-modified earthen masonry. It argues that wet-to-dry strength retention is a more realistic durability indicator than dry compressive strength alone because low-cost walls are exposed to wind-driven rain, capillary rise, damp surfaces, and imperfect maintenance. The review shows that ash stabilizers can improve particle bonding and pore refinement when properly processed, proportioned, compacted, and cured, but excessive ash, poor soil selection, or inadequate detailing can increase water absorption and reduce field reliability. The paper proposes a moisture-durability framework connecting material chemistry, block production, wall detailing, and tropical housing performance. It concludes that agricultural waste ash stabilized earth blocks are promising only when laboratory strength gains are tied to water-resistance testing and moisture-conscious architectural detailing.

Article
Engineering
Electrical and Electronic Engineering

Ahmet Kerem Yumusak

,

Mehmet Bulut

Abstract: Long Range (LoRa) is a chirp spread spectrum (CSS) physical-layer technology that has become a leading candidate for low-power wide-area network (LPWAN) connectivity in the Internet of Things (IoT). At the receiver, the standard demodulator multiplies the incoming signal with a conjugate reference chirp and applies a one-dimensional discrete Fourier transform (DFT), reducing symbol detection to peak search in the frequency domain. While this non-coherent baseline is simple and robust under additive white Gaussian noise (AWGN), its symbol error rate (SER) degrades significantly in frequency-selective multipath channels, where parasitic spectral peaks distort the dominant tone. This paper presents a unified comparative study of seven LoRa detectors for spreading factor seven, six of which share a common one-dimensional DFT engine while a matched-filter bank operates directly in the time domain, with the six DFT detectors differing in their per-bin frequency-domain weighting and decision rule. The detector set spans the standard non-coherent DFT, a non-coherent matched filter bank, two coherent equalizers in the frequency domain (zero-forcing and minimum mean-square error), a phase-only equalizer, a maximal-ratio combiner with non-coherent decision, and an exhaustive maximum-likelihood detector that serves as a near‑optimal reference under the same preamble‑based CSI. To mitigate inter-symbol interference in the multipath case, every transmitted symbol is preceded by a cyclic prefix that converts the linear convolution with the channel into a circular convolution, enabling per-bin frequency-domain processing. Throughout the paper a deployment-realistic receiver model is adopted: the per-bin channel response is estimated by a frequency-domain least-squares estimator from a short preamble, and the noise variance is estimated blindly from the preamble residuals. The quality of the noise-variance estimator is reported separately as a diagnostic. Each detector is evaluated under both AWGN and a two-tap Rayleigh multipath channel through Monte Carlo simulation, and its execution time per call is recorded to provide a complementary view of computational cost. The framework introduced here clarifies how coherent processing, diversity combining, equalization, and exhaustive search trade detection performance against complexity within a single DFT-centric LoRa receiver architecture. The principal quantitative finding is that, under the two-tap Rayleigh multipath channel, the MMSE equalizer reaches SER ≈ 4.4×10⁻⁵ at SNR = −5 dB and tracks the exhaustive maximum-likelihood detector within 0.1 dB across the full SNR sweep, while costing only 1.26× the per-symbol time of the standard DFT receiver. Conversely, the standard non-coherent baseline hits an irreducible 16% error floor and the unregularized zero-forcing equalizer fails to reach the 10⁻² SER level at any SNR considered, isolating MMSE as the recommended choice in the multipath regime at every SNR for which a LoRa link is operationally viable.

Communication
Engineering
Chemical Engineering

Ayush Gupta

,

Michael Harasek

Abstract: Electrochemical CO₂ reduction to ethanol is a promising route for circular-carbon fuel and chemical production, but practical implementation remains limited by coupled membrane, catalyst, transport and system-integration constraints. This Communication reassesses anion-exchange membranes (AEMs) and bipolar membranes (BPMs) using recent 2024–2026 literature. The central argument is that membrane selection is not a passive separation choice; it controls local pH, charge carriers, CO₂ availability, carbonate formation, water activity, proton/cation deliv-ery, product crossover and downstream techno-economic assessment (TEA) and life cycle assessment (LCA) burdens. AEM operation can create alkaline cathodic microenvironments that favor C–C coupling, but bicarbonate/carbonate formation imposes carbon-loss, salt-management and recovery penalties. BPM operation can improve pH separation and carbon management through water dissociation and bicarbonate acidification, but its viability depends on water-dissociation efficiency, co-ion exclusion, junction stability and voltage control. Recent ethanol-selective catalyst studies further show that copper oxidation state, grain boundaries, sub-surface dopants, ionomers, interfacial wettability and dynamic operation interact strongly with membrane-imposed microenvironments. The Communication pro-poses a membrane-centered decision framework linking AEM/BPM selection with ethanol selectivity, single-pass carbon utilization, energy efficiency, durability, TEA/LCA boundaries and future reactor design.

Article
Medicine and Pharmacology
Epidemiology and Infectious Diseases

Yasmin Dunkley

,

Elizabeth Corbett

,

Nicola Desmond

,

Pitchaya Indravudh

,

Nimalan Arinaminpathy

Abstract: Background: African Union (AU) guidance identifies decentralized diagnostics as central to epidemic preparedness. However, the epidemiological role of self-testing across epidemic-prone diseases remains underexplored. Drivers for potential impact of self-testing impact were examined conceptually using a transmission model. Methods: A deterministic SEIR model compared standard-of-care testing with additional self-testing. Global sensitivity analysis using Latin Hypercube sampling and partial rank correlation coefficients (PRCCs) examined parameters influencing reductions in peak disease prevalence (mitigation). Dynamics were illustrated using AU pathogen archetypes (Ebola, Influenza A, Cholera, Coronavirus, and Mpox), estimating the number needed to self-test (NNST) to avert one death as a measure of marginal efficiency. Results: Epidemic mitigation was minimal (median 1.9%; IQR: 0.4%–5.8%); correlated with isolation adherence (PRCC = 0.784), self-testing intensity (PRCC = 0.617), lower R0 (basic reproductive number; PRCC = -0.607) and greater duration of infectiousness (PRCC = 0.370). Achieving a 10% reduction in peak prevalence at R₀ = 1.1 required 34 self-tests per 10,000 people per day, exceeding AU COVID-19 operational benchmark of 10 per 10,000 per week. High-mortality, moderate-transmission archetypes (e.g., Ebola) were most responsive to mortality reductions (Median 1,512 NNST/death averted) compared to Mpox (Median 355,708 NNST/death averted). Adherence to post-test isolation exerted greater epidemiological impact than diagnostic accuracy. Conclusions: The epidemiological value of untargeted self-testing depends on pathogen characteristics and post-test behavioral adherence. Epidemic mitigation effects were generally limited under constrained health-system capacity. However, future demonstration studies evaluating rapid, early decentralized self-testing deployment during Ebola-archetype outbreaks may help identify operationally feasible targeted deployment strategies to support mitigation and mortality reduction.

Article
Computer Science and Mathematics
Artificial Intelligence and Machine Learning

Sameer Kumar Singh

,

Suhrid Pandey

Abstract: Recent work on neural scaling demonstrates consistent performance gains with increased data and model capacity, yet these improvements are typically assessed using surface-level metrics that do not capture factual reliability. In multi-document summarization (MDS), this limitation is particularly acute, as scaling has been shown to amplify hallucination and content distortion. In this paper, we investigate the empirical scaling behaviour of faithfulness-aware transformers under tightly controlled conditions, using LSHT as a fixed architectural and training baseline. Rather than proposing new scaling laws, we analyze how summarization quality, faithfulness and efficiency evolve as dataset size and model capacity are independently increased, while holding architecture, optimization, decoding and hardware constant. All experiments are conducted exclusively on the Multi-News benchmark to avoid cross-dataset confounds. Across ROUGE, coverage, repetition and faithfulness-oriented metrics, we show that lexical overlap and factual consistency follow distinct scaling dynamics. Faithfulness improves most rapidly during early data scaling (approximately 3–4% relative gain from 3k to 12k samples) but exhibits diminishing marginal returns at larger scales, whereas ROUGE continues to increase more smoothly. We further show that faithfulness is more sensitive to data diversity than to volume alone and identify practical scaling regimes that maximize faithfulness gains relative to computational cost. These results establish empirical expectations for scaling faithfulness-aware MDS systems and provide actionable guidance for reliable summarization under realistic resource constraints.

Review
Public Health and Healthcare
Public, Environmental and Occupational Health

Ljiljana Udovicic

,

Peter Sperfeld

,

Frank Gollnick

,

Rüdiger Greinert

,

Beate Volkmer

Abstract: Far-UVC radiation for disinfection in the presence of people in public indoor spaces through unshielded open radiation sources has been promoted for several years, claiming to be a simple solution to reduce infections from airborne pathogens such as bacteria and viruses. This literature review summarizes the existing research on the effectiveness of far-UVC radiation for inactivating pathogens, as well as potential risks to skin and eyes associated with exposure to far-UVC radiation. Further, it discusses radiation protection aspects of using far-UVC radiation in the presence of people, and addresses possible effects of far-UVC radiation on the human environment as well. The literature review shows that despite its antimicrobial and antiviral effectiveness, there is so far no sufficient evidence that far-UVC radiation can be used for disinfection in the presence of people in public indoor spaces without risks for humans and the environment. There are particular concerns about the safety of vulnerable groups such as children, the elderly and people with pre-existing medical conditions. The authors recommend further and extended studies in this field concerning potential risks of far-UVC radiation.

Article
Computer Science and Mathematics
Artificial Intelligence and Machine Learning

Ivan F. Jaramillo

,

Walter Orozco-Iguasnia

,

Rubén Patricio Alcocer Quinteros

,

Ricardo Rafael Villarroel-Molina

,

Alejandro Vilcacundo-Chilusia

Abstract: Maintenance management of stationary combustion engines in the agricultural sector faces critical challenges owing to a reliance on manual methods, which increases the risk of unplanned downtime. This study developed a machine learning-based predictive model to anticipate failures within a 60-day horizon, facilitating the transition from a reactive to a proactive maintenance approach. Following the CRISP-DM methodology and drawing on a historical dataset of 2,250 records from 59 engines, feature engineering techniques were applied to derive 48 predictor variables, while K-Means clustering was employed to identify operational load profiles. The performance of two ensemble algorithms was then evaluated; LightGBM outperformed Random Forest under five-fold cross-validation with a 60/40 temporal split. The proposed model achieved an area under the ROC curve (AUC) of 0.91, a precision of 92.9%, and a recall of 76.1% for detecting actual failures. The findings indicate that gradient boosting techniques are highly effective for optimizing maintenance planning and reducing operating costs in the Ecuadorian agricultural context.

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