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Article
Physical Sciences
Quantum Science and Technology

Sijin Li

,

Wei Wang

Abstract: Quantum metrology exploits quantum states to achieve estimation sensitivity beyond classical limits. In the continuous-variable (CV) regime, the squeezed state has been used to implement deterministic quantum sensing. However, the quantum metrology sensitivity of the squeezed state is significantly affected by losses or detection inefficiencies, which restrict its applications. In this work, quantum distributed sensing is proposed using optical parametric amplified multi-mode entanglement generated from squeezed states. It is found that the sensitivity is robust to loss or detection inefficiency with introduction of optical parametric amplification (OPA), where a two-mode Einstein-Podolsky-Rosen entangled state and a four-mode cluster state are exploited for analysis. The quantum information matrix is calculated for two-mode squeezed state to obtain the optimal bound in comparison with our scheme. It is found that with sufficient OPA gain, the overall sensitivity is robust across a wide range of loss values. This work provides a method for realizing large-scale quantum metrology in real-world applications despite losses or detection inefficiencies.

Article
Computer Science and Mathematics
Artificial Intelligence and Machine Learning

Diego Navarra

Abstract: This paper advances a governance-centred framework for understanding how artificial intelligence contributes to urban sustainability transitions. Drawing on systematic thematic analysis of 250 policy documents across five global cities—Singapore, Amsterdam, Barcelona, Seoul, and Toronto—the paper argues that AI contributes to sustainable outcomes primarily by transforming governance structures rather than through technical optimisation alone. The paper identifies four institutional conditions that determine whether the sustainability dividend of AI deployment is realised: regulatory coherence, multi-stakeholder participation, transparency and auditability of algorithmic decision-making, and adaptive governance capacity. A comparative framework is developed to assess AI governance maturity across urban sustainability domains, including energy management, climate adaptation, mobility, and green public procurement. The paper further examines AI-blockchain integration for climate-responsive governance, drawing on the South Tyrol and Estonia cases as examples of distributed ledger technologies providing the audit trail guarantees that AI systems structurally lack. Findings suggest that governance design—not AI capability—is the primary determinant of sustainable transformation outcomes. The paper contributes to the emerging interdisciplinary literature at the intersection of AI governance, smart city development, and organisational sustainability, offering a practitioner-relevant framework for policymakers, city managers, and business leaders engaged in AI-enabled green transformation.

Concept Paper
Physical Sciences
Biophysics

Ricard Solé

,

Joel Romero-Hernández

,

Guim Aguadé-Gorgorió

,

Manlio De Domenico

Abstract: Complex diseases challenge one of the oldest assumptions in medicine: that illness can be reduced to a single cause. Instead, increasing evidence suggests that many pathologies emerge from the collective dynamics of components interacting across molecular, cellular, physiological, behavioral, and ecological scales. Thus, we revisit the fundamental question of what a disease is through the lens of complex systems theory. In particular, we argue that diseases are better understood as emergent dynamical states of living systems that arise from the breakdown, reorganization, or destabilization of regulatory networks. Within this framework, mathematical models can describe health and disease as alternative attractors in a multidimensional state space, and disease onset often reflects critical transitions driven by stress, perturbation, or loss of resilience. Therefore, concepts from nonlinear dynamics, network theory, ecology, and statistical physics (such as bifurcations, hysteresis, phase transitions, and multistability) provide a unifying language to describe phenomena as diverse as patient comorbidity, psychiatric disorders, cancer progression, epidemic spreading, or neurodegeneration. We also discuss how multiscale models can bridge molecular mechanisms with organism-level behavior to reveal universal principles of complex diseases. This perspective implies that the future of medicine may depend on understanding not only the components of biological systems, but also the laws governing their collective organization, which could open new avenues for prediction, prevention, and control.

Article
Computer Science and Mathematics
Probability and Statistics

C.S. Withers

Abstract: I give estimates of low bias for functions of moments. Let \( F(x) \)be a distribution on \( R^s \). Let \( F_n(x) \) be the empirical distribution of a random sample of size \( n \) from\( F(x) \). Given a functional \( F(x) \), \( E\ T(F_n) \)estimates \( T(F) \)with bias \( \sim n^{-1} \). (The bias is zero for a mean, but this is the exception.) The jackknife and bootstrap estimates only reduce this bias to \( \sim n^{-2} \), and are computationally intensive. I review the main two analytic methods to obtain an estimate of \( T(F) \) of bias \( \sim n^{-k} \)for \( k\leq 4 \)in terms of the functional derivatives of \( T(F) \). I give a chain rule for these derivatives when \( T(F)=g(U(F)) \) and \( g:R^q\rightarrow R \)is any given smooth function with finite partial derivatives at \( U(F)\in R^q \). I apply this to give an estimate of \( T(F) \) of bias \( \sim n^{-k} \)for \( k\leq 4 \), in terms of the derivatives of \( g \)and \( U(F) \). Examples include moment estimates and maximum likelihood estimates.

Article
Public Health and Healthcare
Public Health and Health Services

Cruz S. Sebastião

,

Felícia António

,

João Vigário

,

Joana MK Sebastião

,

Michel Machado

,

Eunice Manico

,

Euclides Sacomboio

,

Joana Morais

,

Deodete Machado

Abstract: Background: Anaemia among blood donors threatens both donor health and blood supply adequacy in sub-Saharan Africa, nevertheless data from Angola remain scarce. Understanding the determinants of anaemia in donor populations is essential for developing targeted interventions and ensuring sustainable blood transfusion services. Herein we investigate the prevalence of anaemia and associated factors among blood donation candidates in Luanda, the capital city of Angola. Methods: We conducted a cross-sectional with 189 blood donors at Angolan National Blood Institute from June 2025 to February 2026. Hemoglobin levels were measured using Auto Hematology Analyzer. Anaemia was defined when <12.0 g/dL. Sociodemographic and donation history data were collected, and logistic regression analysis identified factors associated with anaemia. Results: The overall prevalence of anaemia was 66.7%. Mean age was 31.9 ± 8.92 years, with no difference between donors with and without anaemia (31.6 ± 8.53 vs. 32.1 ± 9.67 years, respectively, p=0.381). Donors aged ≥30 years presented a lower probability of anaemia (OR: 0.83, p=0.536). Gender was associated with anaemia (p<0.001), with male donors showing 88% lower odds [OR: 0.12 (95% CI: 0.05–0.29), p<0.001]. Donors with more than two previous donations had a higher likelihood of anaemia (OR: 1.91, p=0.333). No associations were observed for education level, residence, and employment status (p>0.05). Conclusions: Anaemia prevalence among Angolan blood donors is markedly high, with younger, female gender, and previous donation history as the putative risk factor. These findings underscore the urgent need for donor management strategies, including extended inter-donation intervals for women and routine iron supplementation programs, to safeguard donor health and maintain blood supply sustainability in Angola.

Article
Computer Science and Mathematics
Artificial Intelligence and Machine Learning

Vasco L. Carvalho

,

José C. F. Pereira

Abstract: This work systematically compares two state-of-the-art frameworks-Physics-Informed Neural Networks (PINNs) and Optimizing a Discrete Loss (ODIL)-across benchmark elliptic (Poisson), hyperbolic (Wave), and parabolic (2D diffusion-reaction with unknown source term) problems, culminating in a challenging inverse source reconstruction task: inferring a space-time-varying heat source that enforces a prescribed temperature profile along a moving line. PINNs enforce physics via continuous residuals and automatic differentiation, while ODIL discretizes the PDE on a grid and optimizes discrete field values directly. Results show ODIL consistently outperforms PINNs in convergence speed (often 10−50× faster), accuracy (lower L2 errors, especially for oscillatory/high-frequency solutions), and robustness in inverse settings. Multi-scale Fourier Feature Networks (MsFFN) and Spatio-temporal Multi-scale Fourier Features Networks (STMsFFN) significantly improve PINNs performance on multi-scale problems, while ODIL with multigrid decomposition achieves comparable or superior accuracy at lower cost. The findings highlight the advantages of discrete optimization approaches over neural-network-based physics enforcement for many PDE problems, offering practical insights into hyper-parameter selection and optimization strategies. This work provides a rigorous head-to-head evaluation and guidance for choosing or combining these frameworks in computational science and engineering applications.

Article
Computer Science and Mathematics
Software

Satish Chavali

Abstract: Large language model (LLM)-based coding assistants have achieved adoption rates unprecedented in the history of developer tooling, with over 62% of professional developers reporting active use as of 2024. The dominant narrative frames these tools as straightforward productivity multipliers, citing controlled task completion speedups of 55.8% in the most widely cited study. This paper examines whether that narrative survives contact with longitudinal production evidence and formal mathematical analysis. We present a cost-benefit model that captures both the velocity gain and the quality degradation trajectory of AI-assisted development, deriving a formal break-even expression that predicts when accumulated technical debt erases productivity gains. We then conduct a structured secondary analysis of three published industry cases — a longitudinal code quality study spanning 153 million lines of production code, a large-scale security evaluation of 1,692 AI-generated programs, and enterprise adoption survey evidence from over 2,000 professional developers — to validate the model's predictions against real data. Across all three cases we identify a consistent pattern: measurable short-term velocity gains accompanied by elevated code churn, increased duplication, and reproducible security vulnerability classes specific to LLM-generated code. We term this the AI-assisted productivity paradox and propose a formal governance framework for responsible tool integration. Our central finding is that the productivity case for LLM coding assistants is real but incomplete — standard metrics capture the benefit on a timescale of days to weeks while costs accumulate over months, creating a systematic measurement blind spot in most current adoption programs.

Article
Computer Science and Mathematics
Analysis

Kelly Pearson

,

Tan Zhang

Abstract: We study the extremal behavior of real two-term linear combinations of third-order Zernike modes on the closed unit disk D2. These modes arise naturally in Zernike expansions of optical wavefront aberrations. For each of the six unordered pairwise linear combinations of third-order modes, we classify the interior local extrema in terms of the two real coefficients. The trefoil–trefoil case is treated more generally through linear combinations of primary n-multifoils; harmonicity and the maximum principle show that no interior local extrema occur and that absolute extrema are attained on the boundary circle. For the remaining pairwise combinations, we give analytic conditions for the existence, uniqueness, location, and values of local extrema, including degenerate exceptional cases. We also compare these local extrema with boundary values and describe the associated absolute-extremum problem on the boundary circle. Symbolic computations are included in the appendix to document several algebraic reductions, and numerical illustrations are provided to visualize the resulting classifications.

Review
Computer Science and Mathematics
Artificial Intelligence and Machine Learning

Said Gulyamov

,

Saidakhror Saidakhmedovich Gulyamov

,

Andrey Rodionov

,

Islambek Rustambekov

,

Munavvarkhon Mukhitdinova

Abstract: Modern AI often works as a "black box": it gives an answer, but cannot show why. In high-stakes fields like law, medicine, and government – and under emerging rules such as the EU AI Act – that is a serious problem. Today's most popular explainability tools, such as SHAP and LIME, only approximate a model's reasoning after the fact, and their explanations can be unstable. This review explores a different, often overlooked path: logical systems. We first explain in plain terms what they are and where they come from, then compare the main families – propositional, deontic, and first-order logic paired with modern solvers – by what each can express and guarantee. Our main contribution is a comparative taxonomy organized by explanatory guarantees, which reveals that no existing class simultaneously offers natural-language input, formal verifiability, and reproducibility. We then examine neuro-symbolic systems, illustrated by a representative engine (Causal Logic Engine, CLE), where a language model reads the text but a transparent logical layer makes the decision, checked by a human. The key idea: instead of opening the black box, we move the decision outside it – so the reason behind every answer becomes clear and reproducible.

Technical Note
Environmental and Earth Sciences
Geophysics and Geology

Tomokazu Konishi

Abstract: Exploratory Data Analysis (EDA) has recently enabled the correction of several long standing misconceptions in geophysics, where a number of erroneous theories had been regarded as fundamental laws. These include revisions to the Gutenberg–Richter law, re evaluation of the Omori formula, improved visualisation of plate boundaries around Japan, and renewed prospects for earthquake prediction. To apply EDA effectively to one’s own data, a basic grounding in statistics and the ability to use a statistical software environment are essential. In this article, we introduce the use of R, an open source statistical computing platform, and demonstrate that conducting such analyses is both accessible and straightforward. Earthquake data were obtained from catalogues published by the Japan Meteorological Agency, and all computations were performed in R. The analyses show that modern statistical methods—particularly EDA combined with computational tools—substantially enhance the accuracy, interpretability, and visualisation of seismic data. Key earthquake related quantities are found to follow distinct statistical behaviours, including normal distributions of magnitudes, log normal distributions of released energy, and first order decay patterns with clear half lives in aftershock sequences. Enhanced three dimensional visualisation further clarifies the structural relationships among plate boundaries and seismic activity. Overall, the findings demonstrate that data driven and statistically rigorous approaches not only deepen our understanding of earthquake processes but also challenge several long standing empirical assumptions. This highlights the need for their re evaluation and provides a stronger foundation for future research, including potential advances in earthquake prediction.

Review
Biology and Life Sciences
Food Science and Technology

Steffen Schwarz

,

Dirk W. Lachenmeier

Abstract: Coffee-shop operators frequently treat green-bean cost as a key target for cost optimization, but evidence accumulating across food chemistry, sensory science, hospitality management, and consumer behaviour suggests this framing is incomplete and may be misleading. This narrative review integrates four bodies of literature that have rarely been synthesized together: (i) extraction science governing in-cup quality through total dissolved solids, extraction yield, particle-size distribution, water mineralization, and roast development; (ii) the chemistry of defective coffee beans and their associations with chlorogenic-acid profile, biogenic amines, ochratoxin A, and process contaminants such as acrylamide, furan, and 5-hydroxymethylfurfural; (iii) evidence on coffee-induced gastric acid secretion, dyspepsia, and the modulating effects of roast level and dewaxing; and (iv) hospitality-management research on satisfaction, revisit intention, brand loyalty, and willingness to pay for quality, certified, and sustainable coffee. We argue that the apparent procurement saving from low-grade coffee is offset by losses across multiple revenue-side channels and is amplified by the technical sensitivity of low-grade coffee to extraction error. We propose a conceptual chain linking bean quality to operating profit and present a Monte Carlo simulation comparing two stationary German café configurations — a “Cheap” strategy (bakery / automatic espresso machine / industrial coffee) against a “Quality” strategy (coffee shop / portafilter / specialty coffee) — with all parameters calibrated to a May 2026 German market and price report. Across 10,000 iterations, the Quality strategy generated a higher annual contribution margin than the Cheap strategy in 98.8% of parameter combinations, with a median advantage of approximately €58,000 per year per café. Sensitivity analysis identifies retail price and customer volume as the dominant economic levers in both strategies, while the bean-procurement cost — the very lever a cheap-coffee strategy is designed to exploit — is consistently the weakest driver of profitability. We further note that the chemistry of defective beans differs from that of sound beans in directions that are mechanistically consistent with several reported gastrointestinal effects of coffee, but emphasise that no controlled human study has tested the link between green-bean quality grade and consumer-reported tolerance, and that the available evidence does not currently support a causal claim.

Article
Engineering
Industrial and Manufacturing Engineering

Sarai Estefany Anaya Jorge

,

Alexandra Celeste Cavero Guerrero

,

Renzo Francisco Cardenas Lino

Abstract: Quality failures in the flexible packaging industry increase production costs, generate material waste, and negatively affect manufacturing sustainability. This study developed an integrated Data Analytics model for quality failure management by combining descriptive, diagnostic, predictive, and prescriptive analytics. A dataset containing 1242 real production records was analyzed using operational variables including material grammage, production speed, ambient humidity, paper type, and reel type. Several ML classification algorithms were evaluated, including Logistic Regression, K-NN, SVM, Naive Bayes, Decision Tree, and Random Forest. Model performance was assessed using Accuracy, Precision, Recall, F1_Score, and AUC-ROC metrics. The results showed that nonlinear models achieved superior performance in defect detection compared with linear approaches. Decision Tree obtained the best balance between predictive performance and interpretability, achieving a Recall of 0.927 and an F1_Score of 0.962, while Random Forest achieved the highest AUC-ROC value (0.995). To assess model robustness and reduce the risk of overfitting, a 5-fold cross-validation procedure was applied, confirming the stability and generalization capability of the selected model. A prescriptive optimization model was subsequently integrated with the Decision Tree classifier to identify process configurations associated with lower defect probabilities and lower expected production costs. The proposed framework supports data-driven quality management, reduces the likelihood of defective production, and contributes to sustainable manufacturing through improved resource utilization, lower waste generation, and more efficient operational decision-making.

Review
Public Health and Healthcare
Public, Environmental and Occupational Health

Alex O. Okaru

,

Dirk W. Lachenmeier

Abstract: The African esophageal squamous cell carcinoma (ESCC) corridor extends from Ethiopia to the Eastern Cape and contains some of the highest age-standardised ESCC incidence rates reported anywhere, with five-year survival below 5%. The corridor's heterogeneous incidence (sex ratios from 1:1 to 7:1; tenfold variation between adjacent populations) has resisted single-factor explanation through more than half a century of investigation. We synthesise the multicentre evidence accumulated since the IARC 2018 Group 2A classification of very hot beverages (> 65°C), with particular attention to the African Esophageal Cancer Consortium (ESCCAPE) outputs and to whole-genome sequencing. We argue, on the convergent evidence of animal toxicology, human in vitro mucosa, and population genomics, that thermal exposure acts as a tumour promoter rather than initiator, and that the corridor's heterogeneous burden reflects heterogeneous chemical co-exposure profiles operating against a shared thermal-promoter substrate. Extending the comparative margin-of-exposure (MOE) methodology to oesophageal squamous carcinogenesis, we present an MOE framework distinguishing genotoxic compounds (within-mode-of-action additive) from thermal exposure (separate companion figure), and apply it to two corridor scenarios. The framework supports a four-lever prevention strategy combining tobacco control, alcoholic-strength reduction in unrecorded spirits, clean-cookstove deployment, and graduated thermal-exposure reduction.

Article
Engineering
Mining and Mineral Processing

Samil Hoşkan

,

Bayram Kahraman

Abstract: In open-pit optimization software, metallurgical recovery is commonly treated as a constant for every block, although it varies with ore type and grade. Here, recovery is modelled as a block-grade-dependent variable using 24 laboratory flotation tests on the sulfide ore of a copper deposit in eastern Türkiye, and its effect on net present value (NPV) and the cut-off grade decision is examined. The deposit is split by sulfur content into two routes: sulfide ore (S ≥ 9%) to flotation and oxide ore (S < 9%) to heap leaching. Across a feed grade of 0.22–6.99% Cu, the measured recovery increases with feed grade from about 61% to 94%; the linear correlation is only moderate (r = 0.60), but the relationship is well described by a bounded, saturating recovery–grade curve (R(g) = R_max•g/(g + k); R_max = 0.95, k = 0.12; R² = 0.87). For the leach route, where no test data are available, a fixed 80% recovery is retained throughout. Optimization I (fixed recovery) and Optimization II (variable recovery on the sulfide route) are compared over ten scenarios, using a slope-constrained ultimate pit (50° overall slope, 5% discount rate). Because the deposit's copper is concentrated in high-grade sulfide blocks with measured recovery of about 90–93%, the metal-weighted recovery of the sulfide ore is 88.9%, and the fixed 80% assumption underestimates both recoverable copper and NPV. Under a fixed pit and cut-off, variable recovery yields roughly 8% higher NPV and about 2.9 kt more copper. When the cut-off grade is instead determined economically, variable recovery reclassifies the marginal low-grade sulfide ore (~0.05 Mt, measured recovery below 80%) as uneconomic; even so, total copper output rises from 40.2 kt (fixed) to 43.0 kt (variable) — a slightly smaller gain, because this marginal ore is excluded. Grade-dependent recovery derived from laboratory data thus determines both the recoverable metal and the marginal-ore boundary more realistically than a fixed assumption, and materially affects NPV for this deposit.

Article
Medicine and Pharmacology
Pulmonary and Respiratory Medicine

Anna Janina Höink

,

Simon Tom Scherfeld

,

Anna Movlilishvili

,

Hagen Vorwerk

,

Michel Eisenblätter

,

Johann Philip Addicks

,

Eugen Neumann

Abstract: Background/Objectives: Investigation of whether visual and AI-based assessments of the severity of COVID-19 pneumonia using an established semi-quantitative chest CT scoring system (Pan score) correlate with laboratory parameters as well as pulmonary function, and of the score’s diagnostic value in predicting the patients’ clinical outcome. Methods: This retrospective analysis comprises patients with PCR-confirmed COVID-19, who received a chest CT scan (not more than three days prior to or after the positive PCR test) between March 21, 2020, and December 27, 2021. Each of the five lung lobes was assessed separately using a scoring system ranging from 0 (no pulmonary involvement) to 5 (> 75% pulmonary involvement) by a radiology specialist, an experienced resident physician, a medical student, and a dedicated AI-based chest CT software tool. In addition, pulmonary function and laboratory parameters, the duration of ICU stays and of any required mechanical ventilation, as well as the clinical outcome (discharge vs. death) were recorded, and their correlation with the obtained CT score was analysed. Statistical analyses comprised descriptive baseline comparisons using non-parametric tests, bivariate correlation matrices, and ROC curves to assess diagnostic accuracy. Furthermore, multivariable logistic, ordinal, and age-adjusted spline regression models were constructed to calculate odds ratios and estimate predicted probabilities for cumulative ICU and mechanical ventilation duration thresholds. Results: In total, 351 consecutive patients with confirmed COVID-19 (223 males [63.5%], 128 females [36.5%]; mean age 67.0 years) were included, all of whom underwent at least one chest CT scan. Compared with patients who were discharged, deceased patients had a significantly (p &lt; 0.05) higher mean Pan score (11.7 ± 6.0 vs. 8.8 ± 5.0), higher rates of mechanical ventilation (56.0 vs. 32.1 %), and both a higher incidence (42.7 vs. 25.4 %) and longer duration (10.5 [6.0–20.0] vs. 6.0 [3.0–10.0] days) of ICU stays. The Pan score showed a strong and consistent association with the requirement for mechanical ventilation (r = 0.54; p &lt; 0.01) and the duration of the ICU stay (r = 0.39; p &lt; 0.01). Conclusions: The investigated semi-quantitative CT score is a simple, reliable tool for assessing the extent of COVID-19 pneumonia and can be evaluated both by radiologists and fully automated AI software. While its predictive value for all-cause mortality was only moderate, it showed good performance in predicting the need for and duration of mechanical ventilation, as well as intensive care requirement.

Review
Chemistry and Materials Science
Organic Chemistry

Emiliya V. Nosova

,

Galina N. Lipunova

,

Valery N. Charushin

Abstract: This review covers published data (mostly from 2019–2025) on the synthesis and biological activity of azolo[a]quinoxalines, including pyrazolo-, imidazo- and triazolo-annelated systems. We highlight that most research efforts are directed toward the design of anticancer agents, with additional applications as Toll like receptor antagonists, monoamine oxidase inhibitors, opioid receptor modulators, PI3Kα inhibitors, tubulin polymerization inhibitors, GABAᴀ receptor modulators, VEGFR 2 kinase inhibitors, BRD9 binders, and anti inflammatory, antimicrobial, and antifungal agents. Recent synthetic strategies include Cu catalyzed oxidative annulations, I₂ mediated C–H functionalization, metal free cascade cyclization, and multicomponent reactions, often employing eco friendly catalysts and reductants. A growing number of studies integrate virtual screening, molecular docking, and pharmacophore based in silico approaches to guide lead discovery and optimization. Innovative drug delivery systems, such as nanogels, and hybrid molecules combining azoloquinoxalines with pharmacophores like thalidomide have also been explored. This review emphasizes both the medicinal chemistry aspects of azolo[a]quinoxalines and the synthetic methodologies for their preparation, in the perspective of drug development and discovery.

Article
Computer Science and Mathematics
Artificial Intelligence and Machine Learning

Harris Wang

Abstract: Modern enterprise systems must be both secure and adaptive—able to enforce strict access policies while responding intelligently to changing conditions. Yet the theories that explain intelligent behaviour and the engineering methodologies that build reliable systems have evolved separately, leaving a gap that forces designers to choose between formal guarantees and adaptive intelligence. This paper introduces the Constrained Zoned‑Object Architecture (CZOA), a unified formalism that bridges this gap. CZOA integrates the mathematical rigour of Constrained Object Hierarchies (COH) with the practical, validated structure of the Zoned Role‑Based (ZRB) framework. We show that enterprise systems are a natural species of intelligent systems, and that the combined framework preserves minimality while enabling new capabilities: neural‑enhanced permission mining, semantic embeddings for cross‑zone understanding, adaptive access control, and continuous daemon‑based enforcement. A complete Python implementation (CZOI toolkit) and a logic language (UniLang) make the formalism accessible to engineers. Five case studies across healthcare, finance, traffic, education, and supply chain demonstrate that CZOA delivers sub‑millisecond permission checks, up to 23% improvement in operational metrics, and high‑accuracy anomaly detection (94% precision) while maintaining rigorous security constraints. The paper concludes with a discussion of limitations, threats to validity, and future research directions.

Article
Computer Science and Mathematics
Discrete Mathematics and Combinatorics

Deep Bhattacharjee

,

Ushashi Bhattacharya

,

Shounak Bhattacharya

Abstract: We present a Fourier-analytic treatment of the sphere packing problem in dimension $7$ centred on the scaled root lattice $E_7/\sqrt{2}$. The argument constructs a radial Schwartz function from a weakly holomorphic modular form of weight $7/2$ for $\Gamma_0(2)$ and verifies the Cohn--Elkies sign conditions through the Hauptmodul value $h_2((1+i)/2)=-64$, the Atkin--Lehner eigenvalue of $\theta_{E_7}$, and positivity of the Fourier coefficients of the auxiliary form. These ingredients give the density bound $\Delta_7\le \pi^3/105$, while $E_7/\sqrt{2}$ attains equality.

Article
Computer Science and Mathematics
Discrete Mathematics and Combinatorics

Deep Bhattacharjee

,

Ushashi Bhattacharya

,

Shounak Bhattacharya

Abstract: We prove that the optimal sphere packing density in $\mathbb{R}^4$ is $\Delta_4=\pi^2/16$, achieved uniquely (up to isometry) by $\sqrt{2}\,D_4$, for all packings including non-periodic ones. The proof reduces to a Voronoi-cell lower bound $\mathrm{vol}(V)\ge 8$ via shell localisation, support-function containment for root-aligned configurations, and a coordinatewise-monotonicity reduction to a finite atlas of $176$ Weyl-orbit chambers.
All $176$ Gram-spectral sum-of-squares certificates are confirmed by exact rational arithmetic.

Review
Medicine and Pharmacology
Emergency Medicine

Antonia Socias

,

Rafael Blancas

Abstract: Abstract Background: Caffeine toxicity represents a growing public health challenge due to the widespread availability of highly potent formulations. Ingestions of 3–10 grams can be fatal, with serious toxicity occurring at plasma concentrations 15 mg/L or greater. This review provides a framework explaining its diverse clinical consequences. Methods: A comprehensive literature search was conducted across PubMed, Scopus, and Google Scholar using AI-assisted tools, prioritizing clinical, forensic, toxicokinetic, and molecular mechanism studies while excluding chronic moderate consumption. Results: Caffeine toxicity is dose-dependent, progressing from adenosine receptor antagonism to phosphodiesterase inhibition, intracellular calcium release, and GABA-A antagonism. In overdose, these mechanisms interact synergistically to cause severe neurological, cardiovascular, and metabolic complications. Furthermore, the CYP1A2 metabolic system becomes saturated, prolonging the elimination half-life up to 27 hours and causing a disproportionate rise in plasma concentrations. Interactions with drugs like mexiletine drastically reduce clearance. Conclusions: Severe poisoning stems from complex, synergistic molecular interactions. Hypokalemia serves as a promising, actionable clinical biomarker for severity assessment. When massive ingestions saturate endogenous detoxification, hemodialysis becomes essential for survival. Unregulated markets for pure caffeine require stricter regulatory interventions and intensified clinical surveillance.

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