Browse Articles

Hybrid frequency-domain CFAR detectors for cognitive radio interference resilience and the dual-use security paradox

Abstract Cognitive radio networks (CRNs) enable secondary users (SUs) to opportunistically access underutilized licensed spectrum while protecting primary users (PUs). Robust spectrum sensing under heterogeneous interference and heavy jamming remains challenging: conventional approaches either require extensive prior knowledge or degrade significantly under interference, while basic constant false-alarm rate (CFAR) variants remain vulnerable to structured jamming that contaminates only part of the reference window, causing fixed-rule estimators to either include contaminated samples or discard clean ones. Hybrid CFAR architectures address this by first analyzing reference-window contamination patterns and then adaptively selecting or combining estimation strategies. We adapt eleven such hybrid architectures—originally developed in the radar literature—to frequency-domain spectrum sensing in contested CRNs, and evaluate them across four families (adaptive algorithm selection, order-statistic fusion, intelligent censoring, and weighted processing) against classical CR-CFAR baselines via Monte Carlo simulations using APCO Project 25 as the PU waveform and an OFDMA-based SU, under barrage and swept-FM jamming. Results show that First-Order Difference CFAR achieves the best detection performance through global sorting and statistical jump detection ( $$P_{\text{d}} \approx 1$$ at SNR  $$= 3$$  dB under 50% sweep coverage), followed by Smallest-Of and Order-Statistic Smallest-Of variants. However, this resilience creates a dual-use security paradox: unauthorized devices employing these techniques can resist administrative spectrum control. We address this through an algorithm-aware comb-sweep countermeasure that exploits CFAR reference-window dependencies, inducing near-unity false alarms on vacant channels within a 4 dB JSR denial plateau ( $$-5$$ to $$-1$$  dB) while preserving PU detection, demonstrating that algorithm-aware enforcement can restore spectrum governance in contested environments.

Lessons learned from youth-engaged research methods to conduct qualitative analysis with a transgender and gender-diverse youth advisory board

Although community-engaged research is becoming more common, youth-engaged research methods, particularly its application to qualitative analysis, remains rare. The Research on Identity Specific Eating Disorder Symptoms (RISES) Project developed, partnered with, and maintained a youth advisory board of five transgender, non-binary, and gender-diverse youth in all stages of a qualitative study, including qualitative analysis. Youth advisory board members contributed to a codebook, coded two to six transcripts each, provided feedback on themes and supporting quotes, and authored this paper. After one year, we achieved a retention rate of 83.3% of all youth advisory board members, and 100% of youth advisory board members trained in qualitative analysis. This paper describes the lessons learned from partnering with and training a transgender, non-binary, and gender-diverse youth advisory board to conduct qualitative analysis.

Finite-time composite dynamic compensation control for USVs with rotatable thrusters and multi-channel event-triggered inputs under thruster faults

Third- and concerned-party positions in moral dilemmas: Effect of empathy on ethical judgment

The present study proposes a categorization of moral dilemmas into third-party dilemmas in which a judge’s choice affects only the life or death of others, and concerned-party dilemmas in which not only others’ but also the judge’s life or death is altered. While the former requires the judge to make only moral judgments to save others, another rational decision-making process that considers the judge’s life and death may also impact the latter. We examined ethical judgments based on these two types of dilemmas with a focus on empathic concern. Participants in Experiment 1 were more ethically permissive to save the many including him/herself at the expense of one person in the concerned-party dilemma than in the third-party dilemma, but empathic concern in both types of dilemmas consistently suppressed such utilitarian choices derived from “instrumental harm” (IH), which permits sacrificing a few necessary when it saves many. In Experiment 2, we also confirmed the suppressive effect of empathic concern for utilitarian choices derived from IH in the Pareto concerned-party dilemma in which the death of one person remains fixed regardless of the judge’s choice. We discuss the importance of categorizing these two types of dilemmas in moral dilemmas and demonstrates the public goods dilemma as a Pareto concerned-party dilemma in everyday life.

Maturity-based prediction of UHPC early-age strength: systematic assessment and a new piecewise fitting approach

Socioeconomic equity in maternal health services use in Bangladesh: The role of service readiness in health facilities during the period 2001–2016

Background Equity in health service utilization refers to equal treatment for equal health needs, regardless of socioeconomic status. In low- and middle-income countries, inequity in maternal health service use remains a pressing issue in the pursuit of universal health coverage by 2030. This study examines whether socioeconomic equity in the use of key maternal health services—antenatal care (ANC) from a medically trained provider, facility delivery, and management of complications—improved faster in districts with high facility readiness than elsewhere in Bangladesh between 2001 and 2016. Methods and findings We analyzed data from three rounds of the Bangladesh Maternal Mortality and Health Care Survey and corresponding Bangladesh Health Facility Survey rounds. These datasets were linked at the district level and pooled for the years 2001, 2010, and 2016. Using an adaptation of the Difference-in-Differences (DID) model based on linear probability models, we estimated whether poor-nonpoor gaps in maternal health service utilization changed differently over time in districts with high facility readiness than in districts with lower readiness. Bangladesh achieved substantial improvements in overall maternal health service use during the study period. However, these gains were not equitably distributed. Socioeconomic equity improved modestly for ANC and complication management but worsened significantly for facility deliveries. The gap between nonpoor and poor women widened more in high facility readiness districts than in low readiness districts (p < 0.05). Additionally, equity in ANC use improved among women living within one hour of a private facility (p < 0.05). Conclusions This is the first systematic investigation of the role of facility readiness in maternal health equity in Bangladesh using nationally representative data. Despite overall progress, persistent and, in some cases, widening socioeconomic inequities were observed—especially in facility-based delivery. These findings highlight the need for targeted policy action to ensure that improvements in service readiness translate into more equitable maternal healthcare access and outcomes.

Steatotic liver disease and the risk of fertility-related gynecological disorders in reproductive-aged women: a nationwide cohort study

Longitudinal omics study of transcriptional dynamics in Lactobacillus crispatus

Background The vaginal microbiome is an important component of female reproductive health. Community State Type I (CST-I), which is dominated by Lactobacillus crispatus , is generally considered to be closely associated with a healthy vaginal microecological state. Although the taxonomic composition of CST-I communities remains relatively stable, the transcriptional dynamics of Lactobacillus crispatus across different phases of the menstrual cycle remain unclear. Methods A healthy reproductive-age woman with a stable CST-I vaginal microbiome was enrolled in this longitudinal study. Vaginal secretion samples were collected at six non-menstrual time points throughout a menstrual cycle. Third-generation full-length 16S rRNA gene sequencing and metatranscriptomic sequencing were performed. Differential transcript expression analysis, KEGG pathway enrichment analysis, and Mfuzz time-series clustering were applied to systematically characterize the transcriptional dynamics of the vaginal microbiome across different phases. Results Full-length 16S rRNA gene sequencing confirmed that Lactobacillus crispatus remained the dominant species at all six sampling time points, with no substantial changes in overall community composition. However, metatranscriptomic analysis revealed pronounced phase-specific transcriptional reprogramming. During the pre-ovulatory phase, pathways involved in DNA replication, biosynthesis, and central carbon metabolism were upregulated. On the first day after ovulation, pathways associated with carbohydrate utilization, quorum sensing, and redox homeostasis were selectively upregulated. During the mid-to-late luteal phase, pathways related to cell proliferation and growth were generally downregulated, whereas pathways involved in cofactor biosynthesis, the pentose phosphate pathway, and D-amino acid metabolism showed increased expression. Mfuzz clustering further revealed distinct phase-specific functional transitions in L. crispatus that were absent in non- L. crispatus lactobacilli. Conclusion The ecological dominance of Lactobacillus crispatus is maintained not solely through numerical abundance, but also through rhythmic and phase-specific transcriptional regulation. Dynamic functional remodeling and metabolic plasticity may represent important mechanisms underlying its long-term persistence and ecological dominance within healthy CST-I vaginal communities.

Cross-validation optimism undermines hyperparameter optimisation in rare-event predictive maintenance: a leakage-resilient benchmark for urban electric transport

Assessing the investment risk: An empirical analysis of Altman’s Z-score model

Investors can play a significant role in reviving the economy and addressing the national agenda of poverty elimination through job creation. Though foreign and local investment are the backbone of any economy, especially in developing economies like Pakistan, investors face the challenge of assessing investment risk to protect the capital employed and achieve an appropriate return on investment. The aim of this research is to assess investment risk faced by firms in Pakistan using the most suitable approach, and then to develop an economic model for a comprehensive assessment of the factors influencing investors’ risk, focusing on firm-specific characteristics, economic conditions, and political stability. The introduction of the Investment Risk Index based on Altman Z-scores provides a structured diagnostic approach to assessing investment risk in Pakistan. Earlier studies have mainly used financial ratios to explain risk. The estimation results using an analytical approach (the Investment Risk Framework) confirm that firm-specific characteristics and economic, political, and financial stability indicators significantly impact investment risk. The findings, based on 443 firms over the period 2014–2023, reveal that the proportion of firms in the distress zone increased from 4.8% to 8.5% (a doubling) during the study period. Retained earnings relative to total assets emerged as a strongly correlated factor with investment risk, while the market value of equity relative to total liabilities played a significant role in keeping firms (around 88% of the sample) in the safe zone. For the determinants, the GMM results indicate that past values of investment risk strongly predict future risk. A 1% increase in past risk is associated with a 0.395% higher future risk. Additionally, political stability, GDP growth, inflation, current account balance, broad money, dividend premium paid, and growth opportunities are found to have a significant impact on the investment risk. Furthermore, internal factors such as fixed asset accumulation, firm size, and tax expenses also influence risk, with larger firms facing higher risk. This study underscores the importance of understanding investment risk factors for informed decision-making. The findings offer valuable insights for investors and policymakers, with potential applicability to other developing economies.

Antibacterial activity and surface fractal properties of Ag/CuO-doped hardystonite nanocomposites against bacteria

Mechanistic evaluation of NSC 57774 as a SHP2 inhibitor in gastric cancer: Multi-pathway signaling modulation in vitro

Gastric cancer (GC) remains a leading cause of cancer-related mortality worldwide, driven by late-stage diagnosis, metastatic progression, and therapeutic resistance. Src homology region 2 domain-containing phosphatase 2 (SHP2) has emerged as a critical regulator of oncogenic signaling in gastric tumorigenesis, yet its therapeutic targeting remains underexplored. In this study, we evaluated the anti-cancer efficacy of NSC 57774, a novel SHP2 inhibitor, using integrated bioinformatics and functional assays in AGS gastric cancer cells. Analysis of The Cancer Genome Atlas (TCGA) and UALCAN datasets revealed marked upregulation of SHP2 and multiple receptor tyrosine kinases in gastric cancer tissues. NSC 57774 potently inhibited cell proliferation and migration, demonstrating selective cytotoxicity towards cancer cells over non-cancerous fibroblasts. Mechanistically, NSC 57774 disrupted key oncogenic pathways including MAPK/ERK, AKT and STAT3 in a concentration- and time-dependent manner, with higher doses achieving more sustained pathway suppression. NSC 57774 suppressed NF-κB inflammatory signaling at early timepoints and induced cleaved caspase-3 across all treatment groups at 72 hours, indicative of pro-apoptotic activity. A paradoxical late-phase increase in phospho-p38 was observed at 72 hours, consistent with a compensatory pro-apoptotic stress response. Comparative analysis revealed that NSC 57774 outperformed the commercial SHP2 inhibitor NSC 87877 and doxorubicin in reducing viability and migration of gastric cancer cells. Collectively, these findings position NSC 57774 as a promising candidate for targeted gastric cancer therapy, capable of disrupting multiple signaling pathways involved in tumor progression, metastasis, and inflammation, warranting further preclinical and clinical investigation.

Features of the fatty acid profile of down and guard fibers of felted wool of the Ukrainian Carpathian Mountain sheep breed

Field evaluation of 3-(N-acetyl-n-butyl) aminopropionic acid ethyl ester - IR3535 as a spatial repellent to control malaria: A Randomised, Before-After-Control-Intervention trial

Background Malaria remains a major public health challenge in sub-Saharan Africa. Increasing mosquito resistance to insecticides can significantly limit current vector control strategies. Spatial repellents represent a promising complementary tool by disrupting mosquito human-seeking behaviour. This trial aimed to evaluate the efficacy of IR3535 as a spatial repellent in Tambai, a high-transmission rural area in central Mozambique. Methods This was a randomised, Before-After-Control-Intervention trial. Four Tambai blocks were randomly selected, with 40 households randomly assigned to receive IR3535 spraying and 40 assigned to as a no-repellent control group. Plasmodium falciparum malaria prevalence was estimated in children under 5 years of age using polymerase chain reaction, before, at year one and at year two. Data were first analysed using frequentist methods and subsequently using spatiotemporal Bayesian models, incorporating INLA-based models to assess the impact of repellent intervention on mosquito density and diversity, sporozoite rates, and malaria prevalence in the repellent and control groups. Results A total of 5716 mosquitoes were collected, 57.2% were Anopheles and 42.7% were Culex sp. . An. funestus s.l. females, were the most prevalent mosquito both indoor (92.7%) and outdoor (82.5%), followed by An. gambiae and An. tenebrosus . The total number of An. funestus s.l. females was lower in the repellent group compared with the control group [indoors: 765 vs 1,432; outdoors: 175 vs 293], as was the average number of mosquitoes collected per household [indoors: 18.6 vs 35.0; outdoors: 4.3 vs 7.1]. Spatiotemporal analysis revealed evidence of repellent-associated reduction in mosquito densities, with species-specific and indoor-outdoor differences, highlighting An. funestus s.l. dominance and spatial-temporal clustering patterns. P. falciparum prevalence among children under five declined from 72.6% (95% CI = 64.1–80.2) at baseline to 51.3% (95% CI = 43.5–59.1) at year one and 43.3% (95% CI = 35.7–51.1) at the end of the study, with similar reductions in both repellent and control groups. Sporozoite rates were slightly lower in the repellent group, particularly outdoors, however, these differences could not be directedly attributed to the repellent. Conclusion Our findings indicate that the use of IR3535 as a spatial repellent reduces indoor and outdoor malaria vector densities, which may contribute to reduced malaria transmission. Trial registration ClinicalTrials.gov NCT04419766

Biochar-biostimulant combinations enhance nodulation, yield, and antioxidant defense in mungbean under reduced NPK fertilization

Abstract Reducing mineral fertilizer inputs while maintaining crop productivity is a central challenge for sustainable grain legume production. This study evaluated whether biochar–biostimulant combinations could improve mungbean ( Vigna radiata L.) performance under reduced NPK fertilization. A polytunnel pot experiment was conducted using a completely randomized 2 × 4 factorial design with two NPK levels, 100% and 50% of the recommended dose, and four treatments: biochar alone, biochar + humic acid, biochar +  Bacillus amyloliquefaciens , and biochar +  Pseudomonas fluorescens . Biostimulant addition to biochar improved plant growth, pigment status, and antioxidant response, with the strongest responses observed under reduced NPK supply. Under 50% NPK, biochar +  P. fluorescens increased grain yield by approximately 90% compared with biochar alone and maintained grain yield (4.00 g plant⁻¹) comparable to the 100% NPK biochar-only control (3.85 g plant⁻¹). It also enhanced nodulation, increased total chlorophyll by approximately 60%, and reduced malondialdehyde by approximately 50%. Grain weight was positively associated with nodule number and ascorbic acid content and negatively associated with H₂O₂ content. These findings support biochar-assisted P. fluorescens supplementation as a promising strategy for sustaining mungbean productivity under reduced NPK input, warranting further field validation for broader applicability.

Leveraging expression quantitative trait loci information in single-cell resolution to identify cell-specific genes for gestational diabetes

Background Gestational diabetes mellitus (GDM) is a common pregnancy complication with long-term metabolic consequences for both mother and offspring. While genome-wide association studies (GWAS) have identified risk loci, the cell-type-specific genetic architecture remains poorly characterized due to the limitations of bulk-tissue analyses. Methods We integrated GWAS summary statistics from FinnGen (12,332 cases, 131,109 controls) with single-cell expression quantitative trait loci (sc-eQTL) data from 12 immune cell types in the OneK1K cohort. Using the OTTERS framework and ACAT-O omnibus testing, we performed single-cell transcriptome-wide association studies (scTWAS) to identify GDM-associated genes. We performed bulk-level TWAS as a sensitivity analysis. To investigate the function of significant genes, we performed functional enrichment. Results We detected 14 unique genes significantly associated with GDM across immune cell types (FDR < 0.05), with the strongest signals in CD4 + T cells and monocytes. Notably, ERAP1 and ERAP2 showed associations in 10 of 12 cell types (ACAT. P  = 2.17 × 10 −5 ), and RIOK2 emerged as a shared regulator. Gene Ontology analysis consistently highlighted “antigen processing and presentation via MHC class I” as the top enriched pathway (FDR < 10 −5 ). In contrast, traditional bulk TWAS using GTEx whole blood identified only two genes with nominal associations. Conclusion Our sc-TWAS identifies cell-type-specific GDM-associated genes that are not detected in bulk tissue, highlighting dysregulated antigen presentation in peripheral immune cells. Colocalization prioritizes monocytic LNPEP as the primary causal candidate, while associations for ERAP1 , ERAP2 , and RIOK2 likely reflect complex LD or tissue-specific effects.

Drought trends in the Arabian Peninsula using SPEI and SPEDI indices and their implications for climate adaptation

Predicting medication non-adherence using machine learning: Incorporating Complementary and Alternative Medicine (CAM) beliefs in Malaysian chronic disease patients

Medication non-adherence among chronic disease patients remains a major contributor to poor health outcomes and medication wastage, particularly in multi-ethnic populations such as Malaysia where cultural and religious beliefs strongly influence health behaviours. This study aimed to develop and evaluate machine learning models that integrate demographic, clinical, and complementary and alternative medicine (CAM) belief factors to predict medication non-adherence among patients with type 2 diabetes mellitus, hypertension, and dyslipidaemia. A cross-sectional survey was conducted using a structured questionnaire comprising demographic and clinical data, history of CAM use, the 17-item Complementary and Alternative Medicine Beliefs Inventory (CAMBI), and the Malaysian Medication Adherence Scale (MALMAS). Twelve conventional machine learning algorithms and three stacked ensemble models were utilised using both balanced and unbalanced datasets with all variables as well as feature-selected variables. The best-performing model was a stacked ensemble using logistic regression-selected variables with the unbalanced dataset, achieving the highest AUC of 0.816. Feature selection identified significant variables including CAM beliefs (natural and holistic), race, number of daily doses, number of medications prescribed, religion, educational level, treatment duration, and hypertension status which were later interpreted using SHapley Additive exPlanations (SHAP) analysis. Model performance was further evaluated using the Youden Index and Decision Curve Analysis (DCA) to stratify patients into lower- and higher-risk groups, with a suitable cutoff identified at 0.4. These findings show that incorporating cultural and belief-related factors into machine learning models provides a novel, population-specific approach to predict better non-adherence and guide targeted interventions to reduce medication wastage in chronic disease management.

Temporal-sequential modeling for remaining useful life estimation of turbofan engine

Abstract Accurate prediction of Remaining Useful Life (RUL) is essential for predictive maintenance of turbofan engines, as it helps reduce unexpected failures and maintenance costs while improving system reliability. The objective of this study is to develop an accurate and robust deep learning framework for RUL prediction using multivariate time-series sensor data and to investigate the influence of different optimization algorithms on prediction performance. A hybrid Convolutional Neural Network–Long Short-Term Memory (CNN–LSTM) model is proposed, where convolutional layers extract local degradation features and LSTM layers learn the long-term temporal relationships present in engine degradation data. A sliding-window strategy together with early RUL capping is employed to improve training stability and model generalization. The proposed model is evaluated on all four subsets (FD001–FD004) of the Commercial Modular Aero-Propulsion System Simulation (C-MAPSS) dataset and achieves RMSE values of 12.79, 21.94, 15.09, and 33.71, respectively. Among the evaluated subsets, the model delivers the best performance on FD001 and outperforms several existing deep learning approaches reported in the literature. In addition, five optimization algorithms are systematically compared under the same experimental settings. The results show that Stochastic Gradient Descent (SGD) provides the best convergence behaviour and prediction accuracy for the proposed architecture. Overall, the study demonstrates that combining CNN–LSTM with an appropriate optimization strategy improves the reliability and accuracy of RUL prediction for turbofan engines.

Methicillin-resistant Staphylococcus aureus (MRSA) infection in hospitalized patients is dominated by community-acquired strains: genomic epidemiological evidence

Objective This study aimed to systematically investigate the molecular epidemiological characteristics of methicillin-resistant Staphylococcus aureus (MRSA) in Ningxia hospitals, to elucidate their genetic evolutionary relationships, and to delineate the genomic and phenotypic profiles of the dominant lineages. Methods Clinical isolates of MRSA strains collected between 01/01/2024 and 30/06/2024 were analyzed, employing second-generation gene sequencing technology, combined with MLST and SCC mec typing, along with evaluation of drug resistance and virulence genes. A phylogenetic tree was constructed to analyze strain homology. Results A total of 74 non-duplicate Staphylococcus aureus strains (67 MRSA and 7 MSSA) were collected. The most common clonal strain was ST59-IVa, accounting for 46.27%. This strain exhibited a high prevalence of resistance genes mecA and blaZ , at 91.04%. All five ST22-IVa strains were found to lack mecA and erm genes but showed β-lactam resistance, while possessing both lukS/F-PV ( PVL ) and tsst-1 virulence genes, indicating a significant toxicity risk. Genetic evolution analysis revealed that ST3355, ST4513, and ST59 were closely related, all belonging to SCC mec types IVa; the other ST types exhibited mutations at various loci, with ST5 as the central node, resulting in a wider array of ST and SCC mec typing. Conclusion The ST59-IVa clone is the predominant MRSA strain in Ningxia hospitals, exhibiting multidrug resistance and virulence gene profiles consistent with national trends. However, the emergence of hypervirulent ST22-IVa strains with atypical resistance mechanisms warrants increased vigilance. We recommend enhancing the rational use of antibiotics in hospitals and implementing molecular surveillance for these highly virulent strains.