Search Results (177,835)

Paralytic shellfish toxins (PSTs), potent neurotoxic alkaloids produced by marine dinoflagellates and cyanobacteria, pose severe risks to human health through contaminated seafood and water after absorption into the bloodstream. Current detection methods are limited by matrix interference or ethical concerns. Here, we report a novel screening approach using vanadium pentoxide as an oxidant to convert PSTs into characteristic oxidation products, followed by high-performance liquid chromatography-tandem mass spectrometry (HPLC‒MS/MS) analysis. Under optimized conditions, vanadium pentoxide oxidizes both hydroxylated and non-hydroxylated toxins into distinct major products (P1‒P7), identified by high-performance liquid chromatography‒tandem high-resolution mass spectrometry (HPLC‒HRMS). Vanadium pentoxide oxidation affords excellent product selectivity and, for most PSTs, superior signal intensities, enabling unambiguous differentiation of toxin subgroups. HPLC‒MS/MS method in MRM mode was developed and yielded detection limits of 0.3‒1.5 ng/mL for a broad spectrum of fourteen PSTs in spiked plasma, accuracy of 89.3‒102.2%, and excellent repeatability with intra- and inter-day relative standard deviations (RSDs) ranging from 0.3% to 10.4%. Application of the method to samples from the First Trial OPCW (the Organisation for the Prohibition of Chemical Weapons) Biotoxin Proficiency Test successfully identified STX/neoSTX, confirming its practical utility for trace PSTs detection in complex biological matrices. Full article

This study aims to quantitatively evaluate bone mineral density (BMD) in women with functional hypothalamic amenorrhea (FHA), determine differences across skeletal sites, and summarise current evidence on the diagnosis and management of impaired bone health in this population. Methods: A systematic search of comparative studies evaluating BMD by dual-energy X-ray absorptiometry (DXA) in women with FHA or anorexia nervosa (AN) and healthy eumenorrhoeic controls was performed. Eleven studies met the eligibility criteria, five of which were included in the meta-analysis. The quantitative synthesis comprised 14 group comparisons, with lumbar spine and hip BMD analysed separately. Effect sizes were pooled using Hedges’ g with 95% confidence intervals (CI) under a random-effects model. Sensitivity analyses using REML estimation with Hartung–Knapp adjustment and leave-one-out analyses were performed to assess the robustness of the pooled estimates. Results: The narrative synthesis of 11 studies generally showed lower BMD in women with FHA or AN compared with healthy controls. In the meta-analysis, among women with FHA, hip BMD was significantly lower than in healthy controls (Hedges’ g = −0.60; 95% CI −1.13 to −0.06; p = 0.030; I² = 63%), while a moderate reduction was observed at the lumbar spine (Hedges’ g = −0.68; 95% CI −1.48 to 0.13; p = 0.101; I² = 83%). In women with AN, substantial reductions were observed at both the lumbar spine (Hedges’ g = −1.66; 95% CI −2.28 to −1.04; p < 0.001; I² = 71%) and the hip (Hedges’ g = −1.37; 95% CI −2.33 to −0.42; p = 0.005; I² = 89%). The lumbar spine reduction in AN remained statistically significant across sensitivity and leave-one-out analyses and was the most robust finding, whereas the statistical significance of hip BMD estimates in both FHA and AN and of lumbar spine BMD in FHA was sensitive to the analytical approach or exclusion of individual studies. The systematic review demonstrated that DXA with interpretation based on Z-scores remains the preferred method for skeletal assessment in premenopausal women with FHA. Bone health assessment is recommended after ≥6 months of amenorrhea or earlier in women with severe energy deficiency or a history of fractures. Restoration of energy availability, weight gain, and recovery of menstrual function remain the cornerstone of treatment. When amenorrhea persists and low BMD is confirmed, physiological transdermal 17β-estradiol combined with cyclic progesterone is the preferred hormonal therapy, whereas combined oral contraceptives, bisphosphonates, and denosumab are not recommended for routine management. Conclusions: Functional hypothalamic amenorrhea is associated with reduced BMD, with substantially greater skeletal deficits observed in the AN subgroup. These findings support early assessment of bone health and timely correction of low energy availability in women with FHA. The considerable between-study heterogeneity and sensitivity of some pooled estimates highlight the need for larger prospective studies using standardized diagnostic criteria and uniform skeletal outcome measures. Full article

The narrow edible window period of kiwifruit poses significant challenges for the high-value fresh fruit industry. This study comparatively evaluated the effects of 1-methylcyclopropene (1-MCP), melatonin (MT), and acetylsalicylic acid (ASA) on “Guichang” kiwifruit by analyzing their physiology, energy metabolism, and transcriptomic profiles. The results indicated that 0.5 μL/L 1-MCP, 1.0 mmol/L MT, and 2.0 mmol/L ASA were the optimal concentrations, all of which significantly inhibited ethylene production and respiration intensity. These treatments effectively maintained fruit firmness, vitamin C content, and high energy status by preserving ATP levels and the activities of H⁺-ATPase and Ca²⁺-ATPase while suppressing the activities of CCO, SDH, 6-PGDH, and G-6-PDH. Transcriptomic analysis and RT-qPCR verification revealed that these preservatives re-programmed key respiratory pathways, including glycolysis, the TCA cycle, the pentose phosphate pathway, and oxidative phosphorylation. MT exhibited transcriptomic responses highly similar to 1-MCP (sharing 13 KEGG pathways) and resulted in the lowest decay rate among treatments, whereas 1-MCP showed the strongest maintenance of core firmness. Our findings suggested that MT exhibited promising performance across multiple quality- and energy-related parameters and may serve as a potential alternative treatment for maintaining kiwifruit quality during the edible window period. Future studies should functionally validate the identified candidate genes and evaluate the effects of MT on sensory and flavor attributes under commercial storage and distribution conditions. Full article

Objective. This meta-analysis aimed to assess the effectiveness of stem cell–seeded conduits compared with autografts and empty conduits in preclinical models of peripheral nerve repair. Methods. A systematic review and meta-analysis was conducted of in vivo preclinical studies published between 2013 and 2024. Endpoints included muscle mass ratio, sciatic function index (SFI), nerve conduction velocity (NCV), compound muscle action potential (CMAP) amplitude, and nerve conduction latency. Studies were further classified by stem cell type, graft material, species, and defect length. Results. Across 30 studies, both stem cell–seeded conduits and autografts outperformed controls across functional and electrophysiological measures. Early improvements (0–3 months) in muscle mass ratio were observed with both stem cell grafts (p = 0.014) and autografts (p = 0.027). SFI improved significantly in both groups at early time points, with stem cell grafts maintaining significance beyond 3 months (p = 0.04). CMAP amplitude showed early gains for both stem cell grafts (p < 0.001) and autografts (p < 0.001), with autografts performing slightly better initially (p = 0.033). NCV improved in both groups early, with stem cell grafts maintaining significance beyond 3 months (p = 0.007). Autografts showed early improvements in latency (p = 0.048), whereas stem cell grafts trended toward benefit without reaching significance. Conclusions. These findings suggest that stem cell–seeded grafts may provide functional benefits similar to autografts in peripheral nerve repair compared with empty conduits. Clinically, this method could be valuable when autografts are unavailable or when harvesting is contraindicated. Full article

Asymmetric heat transfer is an intrinsic and defining feature of phase change material (PCM) systems, arising from the nonlinear coupling between conduction, buoyancy-driven convection, interfacial motion, and geometric or operational non-uniformities. This review synthesizes the physical, numerical, and application-specific mechanisms through which asymmetry emerges and shapes the thermal behavior of PCM-based energy systems. We first examine the fundamental origins of asymmetry, highlighting how natural convection, material heterogeneity, and spatially uneven boundary conditions distort temperature fields and melt front evolution even in nominally symmetric enclosures. We then provide a comprehensive assessment of state-of-the-art modeling approaches—including full-domain CFD, advanced interface tracking methods, stability and bifurcation analysis, and reduced-order modeling—emphasizing their capacity to resolve asymmetric flow structures and capture the complex dynamics governing phase transition. Experimental observations from optical, infrared, and flow visualization techniques further validate the prevalence of asymmetric patterns and underscore the need for high-resolution multi-field datasets. Building upon these foundations, the review analyzes the implications of asymmetry across key energy applications such as thermal energy storage, building envelopes, solar receivers, electronics cooling, transportation systems, and industrial heat exchangers. We also provide a literature review on the importance of using multicriteria evaluation as a key tool in the design of multidimensional symmetric and asymmetric PCM systems. In this context, we address and analyze the performance criteria, evaluation metrics, case studies, and optimization strategies to be considered in the design of these systems. Finally, we identify critical research gaps—including multiphysics coupling, uncertainty quantification, CFD–machine learning integration, and the exploration of emerging asymmetric applications—and outline pathways toward next-generation PCM-based technologies that not only accommodate asymmetry but strategically exploit it for enhanced thermal performance. Full article

A-type mold flow analyses were performed to examine the effects of the feedstock flow behavior on the powder particle distribution in the weld zone following the forward collision of two flow fronts during metal powder injection molding. Although the A-type mold cavity and the two converging feedstock flow paths are geometrically symmetric about the central weld plane, the present numerical results indicate that the coupled shear-heating and viscosity variation during flow-front collision break this symmetry, resulting in an asymmetric powder concentration and temperature field at the weld zone. This local departure from mirror symmetry was quantified using a proposed Mirror Asymmetry Index (MAI). The complex rheological characteristics of the weld zone result in a separation of the particles and the binder, which leads to changes in the powder concentration distribution. Such predicted concentration non-uniformity may be relevant to local density variation after de-binding and sintering; however, the present study does not simulate sintering or experimentally measure density or mechanical properties. Thus, to enhance the powder concentration in the weld zone and ensure a uniform distribution of the particles, mold flow analysis simulations, combined with the Taguchi experimental method, were performed to identify the optimal material and processing parameters for the metal powder injection molding process. The results indicate that regions of the weld zone with higher shear rates exhibit lower powder concentrations. In addition, local stagnation occurs at the intersection of the two flow fronts, which causes radial flow and phase-separation effects in the weld zone. Among the four factors examined (melt temperature, mold temperature, particle diameter, and injection flow rate), particle diameter was found to exert the dominant effect on weld-plane powder concentration, while the injection flow rate had the least influence. The optimal material and processing conditions (a melt temperature of 220 °C, a mold temperature of 60 °C, a particle diameter of 5 micron, and a filling rate of 10 cm³/s) improved the powder concentration in the weld zone and achieved a more uniform distribution, raising the mean particle concentration by 63.3% and reducing its standard deviation by 74.2% relative to the default settings. These findings show that geometric symmetry alone does not necessarily guarantee perfectly mirror-symmetric predicted process fields under the numerical assumptions used here. Physical confirmation of the predicted asymmetry remains necessary. Full article

Waste cooking oil (WCO) represents both a growing environmental burden and a promising low-cost feedstock for sustainable biodiesel production. This review critically examines recent advances in the conversion of WCO into biodiesel, with particular emphasis on heterogeneous catalysts derived from waste resources and their integration within a circular bioeconomy. Waste-derived catalysts obtained from eggshells, snail shells, spent coffee grounds, fish and animal bones, chicken waste, and mineral residues such as marble are comparatively assessed in terms of biodiesel yield, reaction severity, recyclability, feedstock tolerance, and sustainability. Several Ca-rich waste-derived catalysts achieve biodiesel yields approaching 90–98%, demonstrating their potential to replace conventional homogeneous catalysts while simultaneously valorizing secondary waste streams. However, the analysis shows that maximum biodiesel yield alone is insufficient for identifying the most sustainable catalyst, because high-temperature calcination, alcohol demand, catalyst deactivation, and limited recyclability can offset apparent performance advantages. Particular attention is therefore given to catalyst recovery and reuse, free-fatty-acid-dependent process selection, and the integration of esterification and transesterification routes for variable WCO feedstocks. The review further evaluates biodiesel performance and emissions and critically examines life-cycle assessment (LCA) and techno-economic assessment (TEA). Available LCA evidence indicates that WCO-derived biodiesel can exhibit substantially lower carbon and cumulative energy burdens than first-generation biodiesel, although outcomes remain strongly dependent on system boundaries, allocation procedures, energy sources, catalyst preparation, and avoided-waste credits. By integrating feedstock pretreatment, waste-derived catalyst selection, biodiesel conversion, engine performance, LCA, and TEA within a unified framework, this review identifies the major research gaps and provides a pathway toward scalable, low-carbon, and economically viable WCO valorization. Full article

Background: Schizophrenia is frequently underdiagnosed or diagnosed late due to the lack of objective diagnostic markers. This study aimed to develop and validate a machine learning model using routine hematological parameters for the auxiliary diagnosis of schizophrenia. Methods: A total of 150 first-episode drug-naïve schizophrenia patients and 150 healthy controls were enrolled. Study parameters included routine hematological parameters and its derived inflammatory markers. Feature selection was performed using Elastic Net regression, followed by the construction of an L2-regularized logistic regression model. Model discriminative performance, calibration, and clinical utility were assessed through internal validation, area under the receiver operating characteristic curve (AUC), calibration curves, and decision curve analysis. An independent cohort of 50 schizophrenia patients and 50 patients with major depressive disorder (MDD) was used for exploratory differential diagnostic evaluation. Results: The final model incorporated 12 features: neutrophil count (NEUT), eosinophil count (EO), mean platelet volume (MPV), hematocrit (HCT), hemoglobin (HGB), neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), systemic immune-inflammation index (SII), systemic inflammation response index (SIRI), neutrophil-to-platelet ratio (NPR), along with age and sex. The model achieved an AUC of 0.859 (95% CI: 0.780–0.937) on the test set, with an accuracy of 0.767, sensitivity of 0.711, and specificity of 0.822. Calibration curves confirmed good calibration, and decision curve analysis further verified its clinical utility. In the exploratory differential diagnostic analysis, the model showed limited performance in distinguishing schizophrenia from MDD. Conclusions: The model based on routine hematological parameters and L2-regularized logistic regression can effectively differentiate first-episode drug-naïve schizophrenia patients from healthy controls, providing a low-cost and easily accessible auxiliary diagnostic tool for clinical practice. Full article

The growing emphasis on environmental, social, and governance (ESG) performance has increased the need for structured decision-support approaches that can assess sustainability maturity while accounting for both operational efficiency and broader sustainability priorities. However, existing sustainability maturity models are often static, sector-specific, or limited in their ability to integrate expert knowledge with data-driven analytical support. In this study, sustainability maturity refers to the extent to which ESG principles and practices are systematically embedded in organizational processes and decision-making, rather than merely reflecting current ESG performance or an aggregate ESG score. This study proposes an integrated sustainability maturity assessment framework that combines lean–green sustainability principles, ESG criteria, Fuzzy Analytic Hierarchy Process (Fuzzy AHP), and exploratory Random Forest analysis, linking expert-based criterion weighting with maturity assessment and feature-level interpretation within a common decision-support architecture. The framework evaluates sustainability maturity across ten industrial sectors using 33 ESG-oriented sub-criteria structured under environmental, social, and governance dimensions, derived from the sustainability literature and relevant standards and frameworks and refined through expert consultation. Twenty-four experienced professionals contributed to the assessment across the ten sectors, which were selected to reflect diverse sustainability practices and sector-specific conditions. Fuzzy AHP is employed to derive the relative importance of the criteria from expert judgments, while the resulting weighted assessment structure is used to determine sector-level sustainability maturity. Random Forest analysis is subsequently applied to the same weighted ESG criteria, using the resulting maturity classifications as target classes, to explore maturity-related patterns and identify influential criteria based on Gini impurity-based feature importance. The results show clear cross-sector variation: Information Technology (0.87) and Energy (0.84) achieved Level 5 maturity, whereas Food (0.55), Textile (0.48), and Logistics (0.46) were classified at Level 3. Regulatory Compliance Initiatives (0.109) and Certification Continuity (0.098) showed the highest feature importance. By integrating expert-based weighting, ESG maturity assessment, cross-sector benchmarking (i.e., comparison of sectors using the same weighted ESG assessment structure), and exploratory machine-learning-based feature prioritization within a single decision-support architecture, the proposed framework enables organizations to identify maturity gaps and prioritize sustainability improvement areas. Rather than serving as a deterministic predictive model, the framework is intended as an adaptable analytical and managerial decision-support tool for sustainability assessment and strategic planning across diverse industrial contexts. Full article

Background: Trans-resveratrol (3,5,4′-trihydroxystilbene) is a natural polyphenolic antioxidant widely used in anti-aging dermocosmetics for its strong radical-scavenging capacity and its activation of cell-protective pathways such as sirtuin 1 (SIRT1). However, its poor aqueous solubility, photochemical lability, and low bioavailability limit its incorporation into topical formulations and its delivery into the skin. Objective: In this study, ethosomal nanocarriers were designed as a phospholipid–ethanol vesicular system to solubilize, stabilize, and control the release of trans-resveratrol for dermocosmetic applications. Microfluidization is not a commonly used method; however, circulating the formulation through the interaction chamber under optimized pressure can produce ethosomes with desirable colloidal stability by this simple process. Methods: Resveratrol-loaded ethosomes were prepared with synthetic phosphatidylcholine (Lipoid P75), ethanol, and vitamin E. Microfluidization was optimized by varying the number of high-pressure homogenization cycles and the applied pressure. Vesicle size, size distribution and distribution uniformity, zeta potential, pH, conductivity, density, and long-term stability were monitored for up to 180 days; morphology was examined by cryogenic scanning electron microscopy (cryo-SEM) and molecular compatibility by Fourier-transform infrared (FTIR) spectroscopy. A trans-resveratrol high-performance liquid chromatography (HPLC) assay was developed and validated according to International Council for Harmonisation (ICH) Q2 guidelines for quantitative analysis. Encapsulation efficiency was determined by HPLC after ultracentrifugation, cytotoxicity was assessed in human keratinocytes (HaCaT), and in vitro release was evaluated using Franz diffusion cells with two different membranes. Results: All ethosome formulations yielded a nanoscale size distribution (median diameter around 190 nm for loaded and around 90 nm for unloaded) and good colloidal stability, with absolute zeta potentials above the 30 mV threshold at early time points and a skin-compatible pH (around 6.5). The optimized formulation (T16; 1.5% w/w trans-resveratrol, 5% w/w phosphatidylcholine (Lipoid P75), 0.3% w/w vitamin E and 30% w/w ethanol, processed with seven microfluidization cycles) achieved a high encapsulation efficiency (EE) of 95.5% on day 1. 84.2% EE was retained after 180 days, consistent with strong partitioning of the lipophilic active into the ethanol–phospholipid bilayer. FTIR confirmed preservation of the phospholipid bilayer and indicated non-covalent loading, with the resveratrol bands largely masked by the dominant lipid signals. Cryogenic Scanning Electron Microscopy (Cryo-SEM) confirmed near-spherical vesicles with narrow size distribution. In vitro release showed a sustained, controlled release profile relative to a 1.5% w/w resveratrol solution. Slower diffusion across the skin-mimicking Strat-M membrane was observed compared to cellulose acetate membrane. Conclusions: Optimized trans-resveratrol-loaded ethosomes represent a stable, efficient vesicular system enabling formulation stability and controlled topical release. The antioxidant and photoprotective efficacy of the loaded system was not assessed in this study and is identified as a topic for future work. Full article

Complex and semi-refractory gold–silver ores pose significant challenges for efficient metal recovery using conventional cyanidation methods. This study investigates the effect of roasting thermal pretreatment on the leaching performance and mineralogical structure of a polymetallic gold–silver ore from northeastern Türkiye. The samples were roasted at 220 °C, 420 °C, and 620 °C prior to cyanidation to evaluate roasting-induced mineralogical transformations and their effects on metal recovery. High-temperature roasting markedly improved both gold and silver recovery. Gold recovery increased from 75% for the untreated ore to 95.84%, while silver recovery increased from 69.72% to 86.12% after roasting at 620 °C. XRD analysis indicated the transformation of pyrite to hematite, while the characteristic reflections of kaolinite and sphalerite were no longer detected at 620 °C. Moreover, the lowest cyanide consumption (6.5 kg NaCN/t ore) was observed after roasting at 620 °C, coinciding with the highest Au and Ag recovery. These results indicate that roasting-induced mineralogical transformations enhance the accessibility of precious-metal-bearing phases during subsequent cyanidation. Overall, controlled high-temperature roasting shows potential for improving Au and Ag recovery while reducing cyanide consumption in complex semi-refractory ores. Full article

A solar air–water heater (SAWH) is a solar collector capable of heating air and water simultaneously. Although many studies have examined the performance and applicability of SAWHs, the effects of operating conditions, weather conditions, and design parameters on their thermal behavior remain unclear. In this study, the thermal behavior of an SAWH operating in simultaneous air-heating and water-heating mode was investigated under various conditions. A numerical model based on energy balance equations was developed and validated against experimental data. The validated model was then used to determine the effects of inlet air and water temperatures, air and water mass flow rates, weather conditions, fin height, and number of fins. The air-side and water-side thermal efficiencies ranged from −18.2% to 83.19% and from −14.58% to 98.87%, respectively, which indicates that improper operating conditions may cause heat loss. The total thermal efficiency ranged from 63.37% to 85.81%. Among the investigated parameters, the inlet fluid temperature, air mass flow rate, solar irradiance, and fin height considerably influenced thermal efficiency, whereas the effects of the other parameters were relatively limited. These findings are expected to provide valuable guidance for predicting SAWH performance and selecting appropriate operating and design conditions, thereby promoting the wider adoption and application of this type of solar collector. Full article

Travel Reservation Strategy (TRS) provides a capacity-constrained approach for managing recurrent congestion by regulating access to selected urban road links. This study develops a Multidimensional Traffic Split and Assignment (MDTSA) model to evaluate TRS within a heterogeneous multimodal transportation system. The model integrates traveler heterogeneity in value of time, five travel alternatives, non-separable car–bus road impedance, reservation-access constraints, and joint mode–route choice under stochastic user equilibrium. A variational inequality formulation is solved using the Method of Successive Weighted Averages. Numerical experiments on the Sioux Falls network show that TRS increases average network speed by 8.1%, reduces average road saturation by 12.5%, decreases total generalized travel cost by 2.3%, and lowers vehicle-hours traveled by 6.5%. The strategy also shifts travel demand away from private cars, whose modal share decreases by 2.48 percentage points, while bus and metro shares increase by 1.91 percentage points in total. Model-comparison results indicate that neglecting traveler heterogeneity or combined travel modes weakens the estimated effects of TRS, while sensitivity analysis shows that the main performance improvements remain stable across the tested reservation-capacity ratios and demand levels. These findings demonstrate the value of multidimensional equilibrium modeling for evaluating reservation-based urban traffic management. Full article

This study evaluated the baseline performance of unmodified Moringa oleifera seeds and crustacean-derived chitosan for uranium removal from aqueous solutions relevant to naturally occurring radioactive material (NORM) contamination. Batch adsorption experiments were conducted using uranium-spiked solutions with nominal concentrations of 10, 50, and 500 µg/L (measured baseline concentrations of 8, 38, and 484 μg/L). A Taguchi L27 fractional factorial design was applied to optimize uranium biosorption parameters for M. oleifera seeds, while chitosan was assessed through baseline comparative batch trials. All batch experiments, including biosorbent-free controls, were conducted in triplicate to evaluate their reproducibility. Chitosan exhibited limited uranium removal, with a maximum of 34.68% at 8 μg/L. It also formed viscous suspensions that hindered filtration. In contrast, M. oleifera seeds demonstrated superior adsorption performance, achieving a maximum removal efficiency of 99.32% and a maximum adsorption capacity of 0.93 mg/g (932 µg/g). Analysis of means (ANOM) and analysis of variance (ANOVA) identified initial pH and initial uranium concentration as the co-dominant factors governing removal efficiency. The highest removal efficiency was obtained at 484 µg/L, pH 4, 25 °C, 2.0 g/L adsorbent dosage, and 90 min contact time. Adsorption isotherm modeling derived from dedicated equilibrium trials showed strong agreement with the Freundlich model (R² > 0.95), consistent with sorption onto energetically heterogeneous surface sites. Overall, unmodified M. oleifera seeds show high baseline efficacy for dilute uranium removal. However, the optimum conditions identified here are more acidic than the near-neutral pH of most NORM-impacted waters; thus, practical implementation must also account for competing carbonate speciation. Full article

Digital twin (DT) technology is increasingly mobilized to improve the efficiency and operational performance of renewable energy (RE) systems. This study maps the efficiency-oriented segment of DT research in RE through a bibliometric analysis of 383 documents indexed in Web of Science and Scopus (2018–September 2026), obtained after screening out records in which the acronym DT denotes another concept, and compares the results with two earlier versions of the corpus. Research gaps are derived through a three-level triangulation of keyword prevalence, co-occurrence cluster composition, and position on the strategic diagram; they are tested across keyword thresholds, clustering algorithms, corpus subsets, and 246 runs of the strategic diagram, and are interpreted as gaps in salience within the analyzed corpus rather than as proof of absence from the wider literature. Annual output roughly doubled each year from 2021 to 2025 under every growth estimator, with China being the leading contributor. Machine learning and energy management form the most developed themes, whereas economic appraisal remains marginal: no economic term reaches the keyword core, no theme is organized around an economic construct in any run, and the two economic magnitudes reported by the most cited documents never set the cost of the twin against its benefit. Three gaps are retained—the absence of standardized appraisal frameworks for the twin itself, the weak consolidation of interoperability research, and the scarcity of work at the integrated, multi-energy scale—together with the peripheral coverage of hydropower and retrofit. Four stakeholder-specific recommendations follow, each linked to its evidence and to an existing practical precedent. Full article