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Article Robust Inference for Step-Stress Experiments under Interval-Censoring(Springer, 2026) Balakrishnan, Narayanaswamy; Jaenada, María; Pardo, LeandroMany moderns products have a long life before failure. Reliability analyses for such highly reliable devices therefore present a practical challenge as obtaining sufficient failure information to adequately assess lifetime behavior will require extended experimental duration. As an alternative, accelerated life testing (ALT) is commonly used to shorten the time to failure of units under test, with the results subsequently extrapolated to normal operating conditions. This paper provides a comprehensive review of robust inferential methods based on density power divergence for analyzing step-stress ALT data. Point estimates and approximate confidence intervals for model parameters, along with robust estimates of some important lifetime characteristics are developed for general lifetime distributions. Subsequently, explicit expressions are derived for four most prominent parametric lifetime distributions: exponential, Weibull, gamma, and lognormal. A semi-parametric approach based on the proportional hazards model and a competing risks scenario are also discussed as extensions of the proposed model. Throughout the manuscript, several open problems are highlighted, along with significant gaps in the literature, to motivate readers and also to promote further research in this important research area. Moreover, to illustrate the importance of step-stress ALTs and the practical utility of robust estimators, we also present some real data sets used in the literature and analyze one of them using robust methods. By analyzing real data, we demonstrate the stability of the Minimum Density Power Divergence Estimator (MDPDE) for different values of the tuning parameter in the presence of outliers. We also analyze the implications of distributional assumptions on parameter estimation. Confidence intervals, including transformed intervals, are examined, with transformed intervals resulting in confidence levels close to nominal level and also provide better interpretability. Our results highlight the importance of robust estimation techniques in the presence of data contamination and also in a careful selection of parametric models for modeling the lifetime data, as these choices significantly influence predictions of lifetime characteristics under normal operating conditions.Article Performance of Publicly Supported Technology Transfer Offices in Turkiye: A DEA-MPI-GM(1, N) Approach(Springer, 2026) Belgin, Onder; Apaydin Avsar, BasakTechnology transfer plays a critical role in the commercialization of knowledge generated by research organizations, with Technology Transfer Offices (TTOs) serving as key institutional intermediaries in this process. This study evaluates the efficiency, productivity change and influencing factors of efficiency of publicly supported TTOs by The Scientific and Technological Research Council of Turkiye (TuBİTAK) in Turkiye using a relational multi-period Data Envelopment Analysis (DEA), the Malmquist Productivity Index (MPI) and the GM(1,N) model of Grey Theory. The study covers the period between 2020 and 2022. The inputs are the number of staff and the number of research requests from industry; the outputs are the number of spin-offs, the number of start-ups, the number of applied and granted patents. The results reveal that TTOs in Turkiye have an increasing efficiency and productivity growth from 2020 to 2022. Furthermore, the size of TTOs, the number of contracted university-industry collaboration projects, the age of TTOs and the number of matching activities between researchers and firms organized by TTOs have a positive effect on the efficiency of TTOs. To the best of our knowledge, this study is the first to analyze the performance and influencing factors of efficiency of the publicly supported TTOs using DEA, MPI and GM(1,N) model.Article Inhibitory Activity of Silver Nanoparticles on Staphylococcus Aureus Growth and α-Hemolysin Gene Expression(Springer, 2026) Karahan, Zehra Can; Yousif Al-Abayechi, Al-Hasan Ali; AL-Khairo, Mazin Yashkur Zaki; Abood, Meethaq SattarBackground Staphylococcus aureus is a major bacterial pathogen responsible for a wide range of infections in humans. The emergence of antibiotic-resistant strains, such as MRSA, has created an urgent need for alternative therapeutic strategies. Silver nanoparticles (AgNPs) have emerged as promising antimicrobial agents; however, their effects on key virulence factors, such as alpha-hemolysin (Hla), have not been fully characterized. Objective This study aimed to isolate S. aureus from clinical samples, synthesize AgNPs, and evaluate their antibacterial activity and ability to inhibit the expression of Hla virulence genes. Methodology Atotal of 250 clinical samples (urine, burns, and sputum) were collected. S. aureus was confirmed by culture, biochemical reactions, the API20 system, Vitek2, and PCR. The morphology and characterization of the AgNPs were prepared using the chemical reduction method and characterized using UV-vis spectroscopy, SEM, XRD, and FT-IR. Results Among the 250 specimens screened, 44 (17.6%) harbored S. aureus, and the isolation rates were similar regardless of the sample type. The antibacterial activity of AgNPs ranged up to 14.41 mm inhibition zone was impressive. The MIC and MBC of AgNPs were determined to be 8 and 64 & micro;g/mL, respectively. The expression of Hla gene was also downregulated in the AgNP group compared to that in the untreated control group, according to real-time PCR data. Conclusion Chemically synthesized AgNPs exhibited potent antibacterial and anti-virulence activities against clinical S. aureus isolates and significantly suppressed Hla gene expression. This dual action highlights their potential as therapeutic agents against S. aureus infections, warranting further investigation of their mechanisms of action.Correction The Evaluation of System Reliability Under Dependent Shock Magnitudes (Vol 28, 22, 2026)(Springer, 2026) Eryilmaz, SerkanIn this article, the statement “Serkan Eryilmaz is a member of the MCAP editorial board” in Competing Interests was inadvertently missed out during production, thus; it was added. The current statement, “The authors declare no competing interests” should have been “Serkan Eryilmaz is a member of the MCAP editorial board”. Competing Interests Serkan Eryilmaz is a member of the MCAP editorial board. The original article has been corrected. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2026.Article Citation - WoS: 1The Evaluation of System Reliability Under Dependent Shock Magnitudes(Springer, 2026) Eryilmaz, SerkanThis paper studies shock models by assuming a certain kind of dependence among shock magnitudes. In particular, discrete time extreme and run shock models are investigated when the shock magnitudes follow discrete autoregressive process of order 1. Exact expressions are obtained for the reliability functions and mean time to failure values under both models. The method for deriving the reliability characteristics is based on the use of probability generating functions. Numerical results are presented when the shocks arrive according to a Binomial process.Article Malignancy in Toxic Thyroid Adenoma: Revisiting Risk Assessment and Identifying Predictors(Springer, 2026) Calapkulu, Murat; Cayir, Derya; Sencar, Muhammed Erkam; Cakal, Erman; Sakiz, Davut; Unsal, Ilknur Ozturk; Tekinyildiz, MerveBackground Toxic adenomas have traditionally been considered benign due to chronic TSH suppression, which is believed to inhibit thyroid tumorigenesis. However, emerging data challenge this dogma, reporting non-negligible malignancy rates even in toxic adenoma. This study aimed to assess thyroid cancer frequency and characteristics in surgically selected patients with toxic adenomas and to compare outcomes with propensity score-matched, surgically treated non-functioning nodules. Methods This retrospective, cross-sectional study included 204 surgically treated patients at a tertiary referral center, comprising 102 surgically selected toxic adenomas and 102 propensity score-matched, surgically treated non-functioning nodules. Clinical, biochemical, sonographic, scintigraphic, and histopathological data were analyzed. Multivariate logistic regression analysis was used to identify independent predictors of malignancy among toxic adenomas. Results In this surgically selected cohort, the malignancy rate was 16.7% for toxic adenomas and 40.2% for non-functioning nodules (p < 0.001). Papillary thyroid carcinoma comprised 82.4% of all cases, making it the leading histotype (82.4%). Among toxic nodules, higher fT4/fT3 ratio (cut-off:2.58, sensitivity:93.3%, specificity:54.2%) and European Thyroid Imaging and Reporting Data System categories 4-5 were independent predictors of malignancy. No significant differences were found between groups in terms of tumor size, invasion, American Thyroid Association risk stratification, or 5-year response rates. Conclusion Among surgically treated patients, the observed malignancy rate in toxic adenomas appears to be higher than traditionally expected. Elevated fT4/fT3 ratio and suspicious ultrasound features warrant closer evaluation. These findings support using ultrasound and biochemical markers in risk assessment of all thyroid nodules, regardless of functional status.Article Evaluation of Cochlear Angular Orientation in Patients with CHARGE Syndrome(Springer, 2026) Kulekci, Cagri; Eroglu, Ergin; Aydin, Canset; Sennaroglu, LeventPurpose This study aimed to evaluate cochlear angulation in patients with CHARGE syndrome and compare it with indi-viduals with normal cochlear anatomy. Methods Eighteen patients with CHARGE syndrome followed for sensorineural hearing loss were retrospectively reviewed and compared with 18 age-matched controls with normal cochlear anatomy. Temporal bone computed tomography (CT) and magnetic resonance imaging were analyzed to assess inner ear malformations and cochlear nerve status. Cochlear angula-tion was measured on axial CT images by calculating the angle formed between lines passing through the basal turns of both cochleae at the level of the round window. Statistical analyses were performed using chi-square and independent samples t-tests. Results Cochlear hypoplasia type III was the most common anomaly in the CHARGE group. Cochlear nerves were fre-quently hypoplastic or absent, whereas all control ears were normal. Mean cochlear angulation was significantly narrower in the CHARGE group compared with controls (94.49 degrees +/- 10.02 degrees vs. 114.02 degrees +/- 8.17 degrees, p < 0.001). Conclusion CHARGE syndrome is associated with significantly altered cochlear angulation, which may contribute to surgi-cal challenges during cochlear implantation. Preoperative recognition of this feature may facilitate safer and more effective surgical planningArticle Circular One/Two/Three-Dimensional Consecutive k-Type Systems(Springer, 2026) Yi, He; Balakrishnan, Narayanaswamy; Li, XiangIn this paper, several circular one/two/three-dimensional consecutive k-type systems are studied, including circular consecutive-k-out-of-n: F systems, circular l-consecutivek-out-of-n: F systems without/with overlapping, circular connected-(k(1), k(2))-outof-(n(1), n(2)): F systems, circular l-connected-(k(1), k(2))-out-of-(n(1), n(2)): F systems without/ with overlapping, circular connected-(k(1), k(2), k(3))-out-of-(n(1), n(2), n(3)): F systems, and circular l-connected-(k(1), k(2), k(3))-out-of-(n(1), n(2), n(3)): F systems without/with overlapping. Reliability functions of these systems are studied using finite Markov chain imbedding approach (FMCIA). Some illustrative examples are provided, and possible applications and generalizations of the established results are also mentioned.Article A Flexible Methodological Approach for Deriving Asymptotic Distributions in Nonlinear Unit Root Tests(Springer, 2026) Omay, TolgaThis paper examines the challenges associated with deriving asymptotic distributions for nonlinear unit root tests. Although the prevalence of non-linear models has increased in recent years, such complex functions make deriving analytical solutions for ergodicity conditions and asymptotic distributions more challenging. The common practice of approximating nonlinear unit root tests with linear functions results in a significant loss of information. This study proposes a novel approach that utilizes the augmented Fourier transformation of the Arctan function to overcome these limitations. The fast convergence properties of the Arctan function within the Fourier framework allow for the derivation of asymptotic distributions for nonlinear unit root tests. The effectiveness of this method is demonstrated by obtaining previously elusive asymptotic distributions for the (existing nonlinear unit root tests) Leybourne et al., in Journal of Time Series Analysis, 19(1), 83-97 (1998) test and achieving improved approximations for the Kapetanios et al., in Journal of Econometrics, 112(2), 359-379 (2003) test. Furthermore, we develop a new unrestricted ESTAR unit root test and demonstrate how previously unattainable asymptotic distributions can be readily derived for this novel test. An empirical application to real exchange rates, incorporating this new test alongside the existing KSS and Kılıç inft tests, reveals that our unrestricted version captures the data generating process more effectively than its restricted counterparts and demonstrates the superior performance of high-power tests that would otherwise be analytically intractable. Therefore, this approach offers a more accurate and robust way to understand the behavior of non-linear unit root tests.Article A General Type of Linear Consecutive-K Systems(Springer, 2026) Yi, He; Balakrishnan, Narayanaswamy; Li, XiangIn this paper, some well-known consecutive k-type systems, including linear consecutive-k-out-of-n: F systems and linear l-consecutive-k-out-of-n: F systems without/with overlapping, are generalized by using more general failure patterns. Finite Markov chain imbedding approach (FMCIA) is applied in a new way for evaluating reliabilities of these generalized new systems. Some illustrative examples are provided for demonstrating the theoretical results established here and also for showing the efficiency of the computational process. Finally, some possible applications and generalizations are mentioned.