Search Results (691)

Diacetylene monomers are known to undergo solid-state 1,4-addition polymerization when their crystal packing satisfies strict geometric criteria; however, the influence of bulky terminal protecting groups on the lattice adjustments required for bond formation remains insufficiently understood. Here, we synthesized amide derivatives of 2,4-hexadiyne-1,6-diamine, crystallized them via antisolvent vapor diffusion, and evaluated their thermal and photochemical reactivity. Single-crystal analysis shows that Boc-protected monomers (Boc-DA) form hydrogen-bond-directed parallel stacks that align diyne units in geometries nominally consistent with topochemical polymerization, yet they exhibit negligible photoreactivity under ambient UV irradiation. Structural inspection indicates that steric congestion from the tert-butoxycarbonyl termini restricts the subtle axial contraction and molecular shifts required for bond formation. Reducing steric bulk or applying combined thermal and photochemical activation enables polymerization of these diacetylenes. These findings demonstrate that globally favorable packing arrangements can coexist with local steric barriers that impose kinetic constraints on reactivity. Modulating terminal-group size and applying multimodal activation therefore provide a simple and tunable strategy to control diacetylene polymerization, offering design principles for switchable polydiacetylene materials in crystal engineering. Full article

Power factor correction in transmission networks with nonlinear loads cannot be addressed solely from the viewpoint of reactive compensation because harmonic distortion and resonance may compromise the expected technical benefits. In this context, this study proposes a resonance-aware and decision-oriented methodology that integrates nonlinear-load screening, weighted bus prioritization based on power factor degradation and harmonic severity, and tuned passive-filter design validated through impedance-frequency analysis and IEEE 519 compliance criteria. The methodology was implemented in DIgSILENT PowerFactory using the IEEE 14-bus test system, where nonlinear loads were allocated at buses 9 and 14 to emulate converter-dominated operating conditions. Under this scenario, the power factor decreased to 0.78271 and 0.85875, while total harmonic distortion increased to 22.01% and 20.07%, respectively. After the implementation of tuned passive filters, the power factor improved to 0.83023 at bus 9 and 0.90414 at bus 14, whereas total harmonic distortion was reduced to 4.61% and 5.22%, respectively, thus restoring compliance with IEEE 519. In addition, load currents decreased by approximately 16–19%. These results demonstrate that the proposed framework provides a technically consistent procedure for identifying critical buses, mitigating dominant harmonics, improving power factor, and avoiding adverse resonance conditions within a unified compensation workflow. Full article

The article describes the results of research on the power supply quality of selected fluorescent lamps and solid-state light sources powered by voltage with different waveforms and supply voltage values. The power factor, total harmonic distortion (THD) factor and values of individual harmonics were measured and their compliance with international standards was assessed. The measurement set-up used and the measurement results obtained with it are described. The results of the experimental research showed that the light sources under consideration did not meet the criteria specified in international standards for the THD factor and the values of individual harmonics, regardless of the shape of the supply voltage waveform. Current total harmonic distortion always exceeded 44%, exceeding the upper limit of 23% specified in the IEC 61000-3-2:2018 standard. The third harmonic values far exceeded the 21.6% of the first harmonics, which is the limit specified in this standard as well. However, it was shown that supplying some light sources with a triangular voltage waveform can increase the illuminance value by up to 28%. On the other hand, the use of a rectangular voltage waveform leads to an increase in the power factor and a decrease in reactive power. Full article

The textile industry faces machinery maintenance challenges due to reactive practices, lack of real-time monitoring, and absent integrated management systems, resulting in unplanned downtime, elevated costs, and quality variability. This study addresses these limitations by proposing a hybrid predictive–prescriptive framework integrating XGBoost 3.2.0 and LSTM models with a multi-objective optimization engine to generate data-driven maintenance recommendations. The framework was validated on four critical components, needles, hooks, needle guides, and thread tensioners, using operational data from a textile plant (November 2024–January 2026). Plant-wide Mean Time Between Failures increased by 38% (15–21 to 24–28 h), while Mean Time To Repair decreased by 15% (5.31 to 4.6 h). These improvements yielded 5.5% lower maintenance costs, 9% less fabric waste, and reduced cost per operating hour from $25 to $23.5. The prescriptive module transformed imperfect predictions into robust decisions by evaluating interventions against production constraints, spare parts availability, and risk criteria. Beyond quantitative gains, the framework enabled sustainable practices including data-driven spare parts policies and condition-based inspections. This work demonstrates that integrating prediction with prescription effectively overcomes structural maintenance challenges in textile manufacturing, providing a replicable methodology for broader industrial adoption. Full article

Phenolic acids and flavonoids remain attractive redox-active scaffolds in medicinal chemistry, where they are widely used for early-stage prioritization and intrinsic reactivity ranking. However, direct comparisons under harmonized conditions remain scarce, limiting structure-based assessment. Here, a structurally diverse panel of hydroxybenzoic acids, hydroxycinnamic acids, flavonoids, a flavanone, and synthetic comparators was profiled using Folin–Ciocalteu response, ABTS radical cation scavenging, DPPH radical scavenging, and reducing power assays. The data reveal pronounced assay dependence alongside clear structure–activity trends. Gallic acid showed the strongest DPPH scavenging (half-maximal inhibitory concentration, IC₅₀ = 4.45 µmol/L) and reducing power (17.26 µmol TE/mg), while quercetin was consistently active across all four endpoints. Eriocitrin (IC₅₀ = 2.47 µmol/L) and rutin (IC₅₀ = 2.66 µmol/L) were particularly effective in the ABTS assay, showing that glycosylation does not abolish cation-radical scavenging. Lipinski’s Rule of Five and Veber oral-bioavailability criteria place these findings within a drug-likeness context. The results also highlight the limitations of the Folin–Ciocalteu assay as a standalone measure of total phenolic content, since its response depends strongly on hydroxylation density. Rather than asserting therapeutic efficacy, this work provides a harmonized comparative dataset identifying phenolic substructures with the strongest and most consistent redox activity, together with the structural drivers underlying these patterns. Full article

Industrial isolated power systems are highly sensitive to load disturbances due to their limited inertia and absence of large-grid support. This article analyzes the dynamic stability of an isolated system with a current available generation contribution of approximately 24 MW, evaluating the integration of a new production plant planned to be integrated in two construction phases of 2 MW each (total 4 MW). The system operates with local generation at 13.8 kV and distribution at 34.5 kV; therefore, demand expansion requires a detailed assessment to maintain safe operating conditions. In addition, the study verifies compliance with spinning reserve requirements for Phase 1 and Phase 2 in accordance with applicable industrial power system criteria, including IEEE 3007.1 and IEEE C37.106, as part of the N−1 security assessment. The developed stability analysis is based on time-domain dynamic simulations using IEEE AC8C excitation models and a UG-8 governor. The results show that, under severe contingencies, the frequency nadir can reach deviations close to 1.5 Hz and RoCoF values above 4 Hz/s. The results indicate that Phase 1 (2 MW) can be incorporated while maintaining acceptable spinning reserve margins, whereas the additional 2 MW corresponding to Phase 2 cannot be integrated under the current operating conditions without violating reserve criteria. However, the system remains stable when generators operate under automatic voltage control, while fixed power factor mode produces less robust responses. Based on this result, the dynamic analysis is focused on the Phase 1 condition under critical contingencies, particularly the sudden outage of the 5 MW and 8 MW generating units, with special emphasis on the outage of the largest generator, mitigated through spinning reserve support and a RoCoF-based load shedding scheme of approximately 4.4 MW. Likewise, the energization of the new plant through the 8 km line requires the evaluation of the available reactive compensation resources, including the use of capacitor banks/reactive support, to prevent underexcitation and maintain acceptable voltage conditions. Full article

As social infrastructure intensively developed during the high economic growth period of the 1970s faces simultaneous aging, there is an urgent need to transition from conventional reactive maintenance to preventive maintenance utilizing various data (data-driven asset management. However, the greatest barrier in practice is that inspection data is unevenly distributed in analog formats such as paper and unstructured files, and heavily relies on the subjective visual evaluation of expert engineers (e.g., discrete graded evaluations from A to D). The intervention of this “Assessor Bias” makes it difficult to ensure the robustness required for direct statistical analysis. This paper serves as a bridge between this analog expert knowledge and quantitative data science. It formulates human cognitive conflicts (true state, peer pressure, avoidance of cognitive load) using the distance-decay model of the Analytic Hierarchy Process (AHP) and the Softmax function, constructing a micro-macro link model accompanied by stochastic variations. Through large-scale multi-agent simulations ($N={10}^7$) validating the model’s convergence, it was demonstrated that in long-tail distributions formed under peer pressure, macroscopic statistical distance metrics such as the Kullback-Leibler (KL) divergence ignore the fact that a small number of true signals are non-linearly suppressed, causing a statistical misinterpretation that “the error is within an acceptable range”. This implies that as long as macroscopic statistical indicators are over-trusted, signs of critical deterioration (minorities) will be structurally marginalized. Returning to the debate on “Homogeneity (Homogenität)” in German social statistics, this paper advocates that in order to realize objective “Micro-segmentation of Homogeneous Statistical Populations,” a paradigm shift from qualitative methods relying on human intuition to quantitative methods incorporating multi-criteria decision making is essential, rather than simply expanding the sample size. Full article

Background: Dietary fibre has been increasingly recognised for its potential role in modulating inflammation, gut-derived uraemic toxins, nutritional status, and kidney-related outcomes in chronic kidney disease (CKD), particularly through mechanisms involving the gut–liver–kidney axis. While nutritional management in CKD has traditionally focused on protein intake, despite growing evidence supporting soluble and insoluble types, the role of dietary fibre remains insufficiently reflected in clinical guidelines. Objective: This systematic review evaluated the effects of dietary fibre intake on inflammatory markers, gut-derived uraemic toxins, nutritional status, kidney function, and mechanistic pathways relevant to gut–liver–kidney axis among CKD patients. Methods: PubMed, Scopus and Medline Complete were searched for observational and interventional human studies. Review articles and animal studies were excluded. A total of 45 met eligibility criteria. Risk-of-bias (RoB) was assessed using domain-based tools, and findings were synthesised narratively across predefined outcome domains. Results: Higher fibre intake was generally associated with reductions in interleukin-6 (IL-6) and selective improvements in inflammatory tone including Tumor Necrosis Factor alpha (TNF-α), while effects on C-reactive protein (CRP) varied. Several fermentable fibres were frequently linked with reduced gut-derived uraemic toxins, including indoxyl sulphate (IS), p-cresyl sulphate (pCS), and less consistently trimethylamine-N-oxide (TMAO). Nutritional markers such as albumin, BMI and overall diet quality were typically maintained or improved. Kidney function was stable across short-term interventions, with suggestions of slower decline in longer studies incorporating fibre-rich dietary patterns. Mechanistic studies frequently reported increased saccharolytic activity and favourable changes in fermentation profiles. Despite growing evidence, soluble fibre remains an underrepresented component in CKD dietary guidelines, warranting further high-quality interventional studies to confirm its therapeutic potential. Full article

Veterinary practice involves frequent interactions with pet owners that may be conflictual, emotionally charged, and ethically complex. These relational demands may contribute to burnout and related distress, but the evidence remains scattered across outcomes and study designs. This scoping review mapped the literature on how veterinarian–client communication and relational experiences are associated with burnout among veterinarians. Five databases were searched, and 17 studies met the inclusion criteria. Most were quantitative, with qualitative and mixed-methods studies also identified. Overall, the findings showed that repeated relational friction with clients, emotionally demanding end-of-life conversations, financial conflicts, and blurred boundaries around availability can contribute to burnout risk. The review also identified mechanisms linking these experiences to distress, particularly emotional reactivity and the effort required to regulate emotions during difficult interactions. Protective factors included supportive teams, autonomy, structured communication training, and interventions such as Acceptance and Commitment Training. These findings suggest that burnout in veterinary practice is shaped not only by workload, but also by the relational demands of client-facing care. Prevention efforts should therefore combine individual support with team-based and organizational strategies that strengthen communication practices and reduce avoidable interpersonal strain. Full article

Background: Renin is a hypoperfusion marker and a good index of renin–angiotensin–aldosterone system (RAAS) activity. The purpose of this study was to evaluate whether the plasma renin concentration (PRC) can represent a tissue perfusion marker for predicting mortality in patients with circulatory shock in intensive care. Methods: This prospective study included patients aged 18 years or older who were hospitalized in the intensive care unit (ICU). A total of 69 patients were enrolled, of whom 37 had circulatory shock and were all diagnosed with septic shock according to Sepsis-3 criteria, while 32 patients did not have shock. Patient groups were compared, and survival analysis was carried out. Mortality predictions of PRC, lactate and combined tests (including PRC, mottling scores, central venous saturation of oxygen, C-reactive protein, procalcitonin, and lactate) were investigated with ROC analysis. Results: ICU 28-day mortality was 36.2% (n = 25) and was significantly higher in patients with circulatory shock than those without (CS:21, 56.8% vs. NS:4, 12.5%, respectively, p < 0.001). The survival was significantly higher in patients without circulatory shock than those with shock (17 vs. 16 days; p = 0.038). The increase in mottling score (HR: 1.64 [95%CI: 1.15–2.33]; p < 0.01) and PRC (HR = 1.01 [95%CI: 1.00–1.02]; p < 0.05) levels and the decrease in glomerular filtration rate (GFR) (HR = 0.98 [95%CI: 0.96–0.99]; p < 0.05) were associated with decreased survival times in the ICU patients (p < 0.001). Combined tests yielded better prediction of mortality than PRC level alone. Conclusions: PRC may reflect circulatory shock and predict survival in critically ill patients; however, larger prospective studies incorporating serial PRC measurements are needed before it can be recommended as an independent biomarker of mortality. Full article

Background: Oral biofilms are a major etiological factor in dental caries, periodontal disease, peri-implantitis, and endodontic infections. Increasing antimicrobial resistance and the limitations of conventional therapies have intensified interest in antimicrobial photodynamic therapy (aPDT). Hypericin, a natural photosensitizer derived from Hypericum perforatum, demonstrates potent reactive oxygen species generation and broad antimicrobial activity; however, its dental applications remain insufficiently synthesized. Objective: To systematically evaluate the antimicrobial efficacy, treatment parameters, safety, and clinical potential of hypericin-mediated aPDT against oral biofilms and infections in dentistry. Methods: This systematic review was conducted according to PRISMA 2020 and registered in PROSPERO CRD42024617727. Electronic searches of PubMed/MEDLINE, Embase, Scopus, and the Cochrane Library (January 2010 to December 2025) were performed. Studies assessing hypericin-mediated aPDT in oral or dental contexts were included. Methodological quality was evaluated using a predefined nine-domain risk-of-bias tool. Results: Eleven studies met the inclusion criteria. Hypericin-mediated aPDT demonstrated strong antimicrobial effects, achieving up to 99% planktonic inactivation and significant biofilm reduction across bacterial and fungal species. Activity was particularly pronounced against Gram-positive organisms, including Staphylococcus aureus and Enterococcus faecalis. However, efficacy against mature biofilms was variable and often dependent on formulation and irradiation parameters. Most studies showed moderate methodological quality, with frequent deficiencies in reporting light calibration and dosimetry. Advanced delivery systems, including liposomal and nanoparticle formulations, improved photodynamic performance. Conclusions: Hypericin-mediated aPDT shows promising antimicrobial activity against oral pathogens and biofilms, with favorable selectivity and safety profiles. Nevertheless, the evidence remains predominantly preclinical and heterogeneous. Standardized protocols and well-designed clinical trials are required before routine dental implementation can be recommended. Full article

Background. Cardiometabolic diseases (CMDs) have become a major health concern among adults living with HIV (ALWH) as antiretroviral therapy (ART) extends life expectancy. Metabolic syndrome (MetS)—a cluster of abdominal obesity, hypertension, hyperglycemia, hypertriglyceridemia, and hypoalphalipoproteinemia—is a key predictor of CMD risk. Despite high HIV prevalence in Panama, data on MetS among ALWH are scarce. Thus, the Colón C3 Study aimed to estimate the prevalence of MetS and its criteria in a large cohort of ALWH in Colón, Panama. Methods. Between April–December 2024, 659 ALWH aged ≥18 years were enrolled at the province’s sole ART Clinic (78.1% of active patients). Participants completed a computer-assisted survey on demographics and social determinants of health (SDoH), underwent anthropometry and body composition assessment, and provided ≥8 h fasting blood samples for glucose, lipid profiles, HbA1c, and high-sensitivity C-reactive protein (hsCRP). MetS was defined using NCEP-R ATP-III criteria, and analyses were stratified by sex. Results. Mean age was 43.9 (range 18–79) years; 55% were female, and 51% identified as Black/Afro-Caribbean. The overall prevalence of MetS was 38.6% (binomial 95% CI 34.5%, 42.9%), exceeding pooled estimates for ALWH in the Americas (30.4%). Among individual criteria, hypoalphalipoproteinemia (59.6%) and hypertension (52.6%) were most prevalent, followed by abdominal obesity (45.2%), hyperglycemia (33.5%), and hypertriglyceridemia (22.5%). Women exhibited significantly higher body fat mass and BMI than men. Mean hsCRP was 7.2 mg/L, indicating persistent inflammation despite virologic suppression. Socioeconomic vulnerabilities, food insecurity (30%), and housing instability (>40%) were common. Conclusions. Findings reveal a substantial cardiometabolic burden among ALWH in Colón and underscore the need for integrated HIV–CMD care models, earlier screening, and natal sex–responsive interventions. The results provide foundational evidence for improving long-term, equitable cardiometabolic outcomes in HIV care across Panama and the broader Latin American region. Full article

As wildfires intensify globally due to climate change, accurate wildfire danger forecasting systems have become essential for effective disaster management and early warning. Fuel Moisture Content (FMC), defined as the ratio of water mass to dry fuel mass, plays a critical role in determining ignition probability and fire spread dynamics. This study conducts a comparative analysis of five major national wildfire danger rating systems: the National Fire Danger Rating System (NFDRS, USA), Canadian Forest Fire Danger Rating System (CFFDRS), European Forest Fire Information System (EFFIS), Australian Fire Danger Rating System (AFDRS), and the Korean Forest Fire Danger Rating System (KFDRS). Using a multi-criteria comparative framework, the systems were evaluated based on fuel classification structure, input variables, modeling approach, and spatiotemporal prediction resolution. The results reveal substantial disparities in spatial resolution (100 m to district-level), temporal resolution (hourly vs. daily), and fuel moisture modeling approaches (physics-based, index-based, and hybrid systems). Specifically, NFDRS and AFDRS provide high-frequency forecasting with hourly temporal resolution, operating at spatial resolutions of 1 km and 100 m, respectively, and incorporating dynamic fuel moisture modeling. In contrast, CFFDRS and KFDRS primarily rely on daily index-based predictions. Furthermore, while many global systems increasingly leverage remote sensing and machine learning for real-time FMC estimation, South Korea’s KFDRS remains predominantly empirical and weather-driven. The analysis identifies critical limitations in the KFDRS, including coarse spatial resolution (district-level), limited integration of Live Fuel Moisture Content (LFMC) modeling, and the lack of AI-augmented hybrid approaches. Accordingly, this study proposes a phased three-stage policy roadmap (2026–2035), emphasizing sensor-network expansion, AI–physics fusion modeling, and high-resolution (10 m) FMC mapping to enhance forecasting accuracy in complex terrains. These findings provide strategic insights for improving wildfire risk management and supporting the transition from reactive response to predictive wildfire forecasting under increasing climate variability. Full article

Multicomponent reactions with isocyanides (IMCRs) enable the one-step assembly of complex molecules and remain a powerful strategy for accessing bioactive scaffolds. Here, we report the first synthesis of an abietane diterpene isocyanide derived from aminoimide methyl maleopimarate 1, a levopimaric acid-maleic anhydride adduct. This isocyanide was further engaged in Passerini, Ugi, and azido-Ugi reactions to provide a series of α-acyloxy- and α-acylaminocarboxamides, as well as tetrazoles, in high yields under optimized conditions. The structures of all products were confirmed by comprehensive physicochemical analysis. In silico ADME, drug-likeness, target prediction, and toxicity studies (SwissADME, ProTox-III) revealed moderate lipophilicity with favorable membrane permeability and solubility, high gastrointestinal absorption, and selective CYP3A4 inhibition with no significant effects on other CYP450 isoforms. The compounds fulfill major drug-likeness criteria, lacking undesirable reactive fragments, with only acceptable deviations in molecular weight and flexibility typical for MCR-derived products. The modifications broaden the spectrum of predicted biological targets while maintaining low overall toxicity and absence of predicted hepato- or carcinogenicity. These results demonstrate that diterpene isocyanide is a valuable building block for chemical libraries of structurally diverse abietane derivatives with peptide-like termini and highlight its potential as a source of cytotoxic, antiviral, and anti-inflammatory candidates. Full article

Background and Objectives: Autologous stem cell transplantation (ASCT) remains the standard of care for relapsed or refractory Hodgkin lymphoma (R/R HL), and an increasing proportion of patients receive programmed cell death protein 1 (PD-1) inhibitors prior to transplantation. Engraftment syndrome (ES) is a noninfectious inflammatory complication classically associated with neutrophil recovery; however, early peri-transplant inflammatory manifestations remain poorly characterized and may mimic infectious complications. We aimed to evaluate peri-transplant inflammatory events after ASCT, with particular emphasis on ES-compatible manifestations occurring before neutrophil engraftment and their association with prior PD-1 inhibitor exposure. Materials and Methods: In this single-center retrospective cohort study, 64 consecutive adult patients with HL undergoing ASCT between 2018 and 2025 were analyzed. ES was defined according to Spitzer and Maiolino criteria. Inflammatory manifestations fulfilling these criteria but occurring prior to neutrophil recovery were classified as pre-engraftment syndrome (pre-ES). Clinically significant events were defined by the requirement for systemic corticosteroid therapy. Clinical and laboratory parameters were compared using non-parametric statistical analyses. Results: No cases fulfilled the Spitzer criteria for classical ES, while three patients (4.7%) met the Maiolino criteria, none requiring corticosteroid therapy. Using the broader Maiolino definition, pre-ES was observed in 34 patients (53.1%) when the conventional engraftment time window was disregarded; however, only three patients required systemic corticosteroid therapy. Importantly, all three cases also fulfilled the Spitzer criteria outside the conventional time window, whereas the remaining Maiolino-defined pre-ES cases were self-limiting. All steroid-requiring pre-ES cases occurred exclusively in PD-1-exposed patients, and prior PD-1 therapy was significantly associated with severe pre-ES (p = 0.0007), although this finding is based on a very small number of events. These patients also demonstrated significantly higher early C-reactive protein (CRP) levels. Conclusions: While classical ES after ASCT was uncommon, clinically significant pre-ES occurred exclusively in PD-1-exposed patients. These early inflammatory events may represent a distinct phenotype and require prompt recognition and timely corticosteroid therapy after exclusion of infection. Prospective studies are warranted to validate these findings and refine risk stratification and monitoring strategies. Full article