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This paper investigates the asymmetric behavior of oil price volatility using different types of Asymmetric Power ARCH (APARCH) model. We compare the estimation and forecasting performance of the models estimated from the maximum likelihood estimation (MLE) method and support vector machine (SVM) based regressions. Combining nonparametric SVM method with parametric APARCH model not only enables to keep interpretations of the parametric models but also leads to more precise estimation and forecasting results. Daily or weekly oil price volatility is investigated from March 8, 1991 to September 13, 2019. This whole sample period is split into four sub-periods based on the occurrence of certain economic events, and we examine whether the asymmetric behavior of the volatility exists in each sub-period. Our results indicate that SVM regression generally outperforms the other method with lower estimation and forecasting errors, and it is more robust to the choice of different APARCH models than the MLE counterparts are. Besides, the estimation results of the SVM based regressions in each sub-period show that the ARCH models with asymmetric power generally perform better than the models with symmetric power when the data sub-period includes large swings in oil price. The asymmetric behavior of oil price volatility, however, is not detected when the analysis is done using the whole sample period. This result underscores the importance of identifying the dynamics of the dataset in different periods to improve estimation and forecasting performance in modelling oil price volatility. This paper, therefore, examines volatility behavior of oil price with both methodological and economic underpinnings. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to evaluate the effects of thyroid-stimulating hormone (TSH) suppressive therapy on bone mineral density (BMD) and bone turnover markers (BTMs) in differentiated thyroid cancer (DTC) patients after postoperative 1–2 years in Northeast China. Methods: Five male, sixteen premenopausal, and eight postmenopausal female DTC patients receiving TSH suppressive therapy after thyroidectomy were enrolled. Patients were matched with healthy controls in a ratio of 1:2. All participants completed postoperative 1-year follow-up, and postmenopausal women completed 2-year follow-up. We measured BMD of the lumbar spine (LS), femoral neck (FN), and total hip (TH) using dual-energy X-ray absorptiometry (DXA). Bone formation marker P1NP and bone resorption marker β-CTX were also evaluated. Fracture risks were assessed by FRAX. Results: There was no difference in BMD and BTMs between DTC patients and controls in the male group at 1-year follow-up. In the premenopausal women, the baseline P1NP was significantly lower in DTC patients than in the controls. The LS-BMD, FN-BMD, and TH-BMD in DTC patients were all higher than those in controls at 1-year follow-up. The difference in FN-BMD was not significant after adjusting for baseline P1NP. In the postmenopausal women, no differences in BMD and BTMs were observed between DTC patients and controls at the 1-year and 2-year follow-up. Conclusion: Our study indicated that postoperative 1-year TSH suppressive therapy did not show detrimental effects on BMD and BTMs in men, premenopausal, and postmenopausal DTC patients. The 2-year postoperative TSH suppressive therapy did not lead to additional loss of bone mass in postmenopausal DTC patients. [ABSTRACT FROM AUTHOR]

Hong and Kao (2004) proposed a class of general applicable wavelet-based tests for serial correlation of unknown form in the residuals from a panel regression model. The tests can be applied to both static and dynamic panel models. Their test, however, is computationally difficult to implement, and simulation studies show that the test has poor small-sample properties. In this paper, we extend Gençay's (2010) time-series test for serial correlation to panel data case. Our new test is also wavelet based and maintains the advantages of the Hong and Kao (2004) test, but it is much simpler and easier to implement. Furthermore, simulation results show that our test has quicker convergence rate and hence better small-sample properties, compared to Hong and Kao (2004) test. We also compare our test with several other existing tests for series correlation, and our test has in general better statistical properties in terms of both size and power. [ABSTRACT FROM AUTHOR]

Dielectric polymers for electrostatic energy storage suffer from low energy density and poor efficiency at elevated temperatures, which constrains their use in the harsh-environment electronic devices, circuits, and systems. Although incorporating insulating, inorganic nanostructures into dielectric polymers promotes the temperature capability, scalable fabrication of high-quality nanocomposite films remains a formidable challenge. Here, we report an all-organic composite comprising dielectric polymers blended with high-electron-affinity molecular semiconductors that exhibits concurrent high energy density (3.0 J cm−3) and high discharge efficiency (90%) up to 200 °C, far outperforming the existing dielectric polymers and polymer nanocomposites. We demonstrate that molecular semiconductors immobilize free electrons via strong electrostatic attraction and impede electric charge injection and transport in dielectric polymers, which leads to the substantial performance improvements. The all-organic composites can be fabricated into large-area and high-quality films with uniform dielectric and capacitive performance, which is crucially important for their successful commercialization and practical application in high-temperature electronics and energy storage devices. Dielectric polymers are widely used in electrostatic energy storage but suffer from low energy density and efficiency at elevated temperatures. Here, the authors show that all-organic composites containing high-electron-affinity molecular semiconductors exhibit excellent capacitive performance at 200 °C. [ABSTRACT FROM AUTHOR]

Inflation targeting is a common monetary policy regime. Inflation targets are often flexible in the sense that the central bank allows inflation to temporarily deviate from the target to avoid causing unnecessary volatility in the real economy. In this paper, we propose modeling the degree of flexibility using an autoregressive fractionally integrated moving average (ARFIMA) model. Assuming that the central bank controls the long-run inflation rate, the fractional integration order becomes a measure of how flexible the inflation target is. A higher integration order implies that inflation deviates from the target for longer periods of time and consequently, that the target is flexible. Several estimators of the fractional integration order have been proposed in the literature. Grassi and Magistris (2014) show that a state-based maximum likelihood estimator is superior to other estimators, but our simulations show that their finding is over-biased for a nearly non-stationary time series. To resolve this issue, we first proposed a Bayesian Monte Carlo Markov Chain (MCMC) estimator for fractional integration parameters. This estimator resolves the problem of over-bias. We estimate the fractional integration order for 6 countries for the period 1993M1 to 2017M9. We found that inflation was integrated to an order of 0.8 to 0.9 indicating that the inflation targets are implemented with a high degree of flexibility. [ABSTRACT FROM AUTHOR]

The flowering transition is a qualitative change in the life cycle of higher plants and an important turning point in the transition from vegetative to reproductive growth. Despite the significant importance, the molecular regulation mechanism of the flowering transition of mei (Prunus mume) remains poorly defined. In this study, RT-PCR was used to clone a LFY (LEAFY)-like gene in P. mume 'Changrui Lve' and functional characterisation of the gene was carried out. The gene showed high homology to the homologous genes of other woody plants, suggesting that PmLFY-like gene exhibits relatively high conservation as flowering-related genes. Expression of PmLFY1 gene in different organs by real-time quantitative PCR showed that this gene was highly expressed in the late stage rather than early stages of flower bud differentiation in P. mume, thereby exhibiting an active regulatory role in flower organ differentiation. Overexpression of LFY1 in Arabidopsis exhibited phenomenal phenotypic changes in transgenic plants, wherein PmLFY-like gene demonstrated the ability to advance the flowering and promoted the transition of inflorescence meristem to floral meristem. Thus, the PmLFY-like gene was not only involved in regulating the duration of flowering and transition to flowering but also played a role during all stages of inflorescence and flower development. These results can be used to conduct a comprehensive and systematic study of the gene functions which can lay the foundation for the molecular research of flowering in mei. [ABSTRACT FROM AUTHOR]

To evaluate the relationship between smoking and both antithyroperoxidase antibody (TPOAb) and antithyroglobulin antibody (TgAb) positivity in subjects from Panshan, Zhangwu, and Huanghua with mildly deficient, more than adequate, and excessive iodine intake, respectively. Smoking-related data were collected by questionnaire, and laboratory measurements of TPOAb, TgAb, and thyrotropin (TSH) were determined at baseline and follow-up. (1) A 1.48-fold increased risk of TPOAb positivity was found in smokers than in non-smokers after adjusting for confounders (age, sex, and areas) (OR[95% CI] = 1.48[1.12-1.95], p = 0.01). (2) Among female subjects, the prevalence of thyroid autoantibodies in smokers was increased than that in non-smokers in Panshan, Zhangwu, and Huanghua (TPOAb): 16.79 vs. 8.89%, 14.14 vs. 11.09%, 19.53 vs. 9.57%; TgAb 15.32 vs. 9.29%, 12.79 vs. 11.94%, 17.19 vs. 10.55%, respectively). The difference was significant in Panshan after adjusting for age. (3) Female long-term smokers (> 20 years) had an increased frequency of thyroid autoantibody positivity than non-smokers after adjusting for confounders (TPOAb OR[95% CI] = 1.60[1.10-2.34]; TgAb OR[95% CI] = 1.31[0.88-1.94]). (4) There was no difference in the incidence of thyroid autoantibodies among non-smokers, new smokers, and long-term smokers at follow-up. (5) TSH was greater in TPOAb-positive subjects than in seronegative smokers (1.56 vs. 1.20 mU/L, p < 0.001) and non-smokers (1.97 vs. 1.58 mU/L, p < 0.001). However, TSH was also greater in non-smokers than in smokers, regardless of whether subjects were positive (1.97 vs. 1.56 mU/L, p = 0.04) or negative (1.58 vs. 1.20 mU/L, p < 0.001) for TPOAb. Long-term smoking could increase the prevalence of thyroid autoantibodies in a population with mildly deficient iodine intake. TSH levels were lesser in smokers than in non-smokers and greater in subjects with thyroid autoantibody positivity than in seronegative subjects. The influence of smoking on TSH levels was independent of thyroid autoantibody levels. [ABSTRACT FROM AUTHOR]

Apoptosis occurs in many autoimmune diseases. Excess iodine induces thyrocyte apoptosis and increases the incidence and prevalence of autoimmune thyroiditis (AIT). However, the sequence of events between the appearance of thyrocyte apoptosis and the occurrence of thyroiditis remains uncharacterized. Furthermore, few studies have investigated the role of macrophage phagocytosis in the development of AIT. Therefore, we evaluated the relationship between apoptosis and inflammatory infiltration in NOD.H-2h4 mouse thyroids by comparing the sequence of events in tissue samples. We also investigated the role of macrophages by comparing macrophage phagocytosis function in BALB/c, C57BL/6, and NOD.H-2h4 mice treated with different levels of iodine. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assays and thyroid inflammatory scores revealed that apoptosis (2 weeks) occurred before inflammatory infiltration (4 weeks). Phosphatidylserine (PS) expression on the extracellular surface of the cell membrane and double-stranded DNA fragments associated with apoptosis appeared at 2 and 8 weeks, respectively. Additionally, although apoptosis was enhanced in the thyroids of mice supplemented with excess iodine (0.05 ± 0.12 vs 1.63 ± 0.82% for BALB/c, 0.09 ± 0.14 vs 1.51 ± 0.34% for C57BL/6, and 0.07 ± 1.11 vs 4.72 ± 0.62% for NOD.H-2h4 mice), only NOD.H-2h4 mouse thyroids presented with inflammation. Furthermore, macrophages from NOD.H-2h4 mice (44.46 ± 1.79%) exhibited decreased phagocytotic activity relative to that in BALB/c (54.21 ± 4.58%) and C57BL/6 (58.96 ± 4.04%) mice. There were no differences in phagocytosis function between NOD.H-2h4 mice supplemented with excess iodine or left untreated (24.50 ± 2.66 vs 21.71 ± 1.79%, p = 0.06). In conclusion, deficiencies in the apoptosis clearance of macrophages in NOD.H-2h4 mice may constitute an early pathogenic mechanism in AIT that is not influenced by iodine intake. [ABSTRACT FROM AUTHOR]

Key message: Expression analyses revealed that floral transition of Rosa odorata var. gigantea is mainly regulated by VRN1, COLs, DELLA and KSN, with contributions by the effects of phytohormone and starch metabolism.Abstract: Seasonal plants utilize changing environmental and developmental cues to control the transition from vegetative growth to flowering at the correct time of year. This study investigated global gene expression profiles at different developmental stages of Rosa odorata var. gigantea by RNA-sequencing, combined with phenotypic characterization and physiological changes. Gene ontology enrichment analysis of the differentially expressed genes (DEGs) between four different developmental stages (vegetative meristem, pre-floral meristem, floral meristem and secondary axillary buds) indicated that DNA methylation and the light reaction played a large role in inducing the rose floral transition. The expression of SUF and FLC, which are known to play a role in delaying flowering until vernalization, was down-regulated from the vegetative to the pre-floral meristem stage. In contrast, the expression of VRN1, which promotes flowering by repressing FLC expression, increased. The expression of DELLA proteins, which function as central nodes in hormone signaling pathways, and probably involve interactions between GA, auxin, and ABA to promote the floral transition, was well correlated with the expression of floral integrators, such as AGL24, COL4. We also identified DEGs associated with starch metabolism correlated with SOC1, AGL15, SPL3, AGL24, respectively. Taken together, our results suggest that vernalization and photoperiod are prominent cues to induce the rose floral transition, and that DELLA proteins also act as key regulators. The results summarized in the study on the floral transition of the seasonal rose lay a foundation for further functional demonstration, and have profound economic and ornamental values. [ABSTRACT FROM AUTHOR]

Purpose:: MicroRNA-326 (miR-326), as a member of the microRNA (miRNA) family, which includes endogenous single-stranded, conserved, noncoding small RNAs, has been reported to play important roles in autoimmune diseases such as multiple sclerosis and systemic lupus erythematosus. However, few studies of the role of miR-326 in autoimmune thyroiditis (AIT) have been published. Here, we explored the roles of miR-326 and the involved pathway in iodine-induced AIT. Methods:: NOD.H-2 mice, which are a model of human AIT, were randomly divided into a normal water control group and a high-iodine group. Mice in the high-iodine group were administered 0.05% NaI (~1000 times the normal daily iodine intake), and mice in the control group received sterile water. Furthermore, we evaluated small interfering RNA (siRNA) interference in spleen mononuclear cell experiments in vitro. Results:: In this study, we found that Th17 cells were significantly increased with a high expression of miR-326 in an iodine-induced thyroiditis NOD.H-2 mouse model. In addition, the expression of Ets-1 protein, a negative regulator of Th17 differentiation, was significantly decreased. Intriguingly, our analysis showed that Ets-1 protein expression was negatively correlated with miR-326 levels in AIT mice ( r = −0.814, p < 0.01). Our study indicated that miR-326 inhibited Ets-1 protein expression and promoted the differentiation of Th17 cells during the onset and development of AIT. The addition of a miR-326 inhibitor reversed Th17 cell production and Ets-1 protein expression, supporting this hypothesis. Conclusions:: The results of our study suggest that miR-326 may target the Ets-1 protein to contribute to iodide-induced thyroiditis, providing a new theoretical basis for the use of miRNA targeting therapy for the treatment of autoimmune diseases. [ABSTRACT FROM AUTHOR]

Complex multiphase waste system purification, as one of the major challenges in many industrial fields, urgently needs an efficient one-step purification method to remove several pollutants simultaneously and efficiently. Multi-functionalized magnetic nanoparticles, FeO@SiO-MPS-AM-DMC-AMPS, were facilely prepared via a one-pot in situ polymerization of three different functional monomers, AM, DMC, and AMPS, on a FeO@SiO-MPS core-shell structure. The multi-functionalized magnetic nanoparticles (MNPs) are proven to be a highly effective purification agent for oilfield wastewater, an ideal example of industrial complex multiphase waste system containing cations, anions, and organic pollutants. Excellent overall removal efficiencies for both cations, including K, Ca, Na, and Mg of 80.68 %, and anions, namely Cl and SO, of 85.18 % along with oil of 97.4 % were shown. The high removal efficiencies are attributed to the effective binding of the functional groups from the selected monomers with cations, anions, and oil emulsions. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of the present study was to design and fabricate endosomal pH-sensitive dual-ligand-modified micellar nanoparticles to achieve enhanced drug delivery to tumor cells and facilitated intracellular drug release. Methods: End-group-carboxylated poly(2-ethyl-2-oxazoline)-poly(D,L-lactide) and cyclic Arg-Gly-Asp-Tyr-Lys- and anti-prostate specific membrane antigen antibody-modified diblock copolymer poly(2-ethyl-2-oxazoline)-poly(D,L-lactide) were synthesized and characterized by H NMR and gel permeation chromatography, and self-assembled into micelles. Paclitaxel-loaded dual-ligand-modified micelles were prepared by thin-film hydration method, and characterized by dynamic light scattering, transmission electron microscope, pH-dependent in vitro release and stability. Intracellular paclitaxel delivery was measured by flow cytometry and imaged by confocal microscopy. In vitro cytotoxicity was studied in the 22Rv1 xenograft prostate tumor cell lines. Results: The prepared dual-ligand-modified micelles with about 30 nm in diameter and rapid intracellular drug release behavior at endo/lysosomal pH were very effective in enhancing the cytotoxicity of paclitaxel against 22Rv1 cells by increasing the cellular uptake, which was verified the correlation with the expression of integrin αβ and prostate specific membrane antigen in tumor cells by flow cytometric analysis and confocal microscopy, compared with single ligand-modified micelles. Conclusion: These findings provided valuable information that the application of combining of dual-ligand modifications with pH-sensitivity to polymeric micelles may be a promising approach in the efficient delivery of anticancer drugs for treatment of integrin αβ and prostate specific membrane antigen expressing prostate cancers. [ABSTRACT FROM AUTHOR]

The traditional causality relationship proposed by Granger (Econometrica 37(3):424-438, ) assumes the relationships between variables are short range dependence with the same integrated order.Chen (J Forecast 25(3):193-200, , J Forecast 27:607-620, ) proposed a bivariate model which can catch the long-range dependence among the two variables and the series do not need to be fractionally co-integrated. A fractional integrated transfer function is introduced to catch the long-range dependence in this bivariate causality model and a pseudo spectrum based estimator is proposed to estimate the long memory parameter in the transfer function. In recent years, a wavelet domain-based method has gained popularity in estimations of long memory parameter in unit series. No extension to bi-series or multi-series has been made and this paper aims to fill this gap. We will construct an estimator for the long memory parameter in the bi-variable causality model in the wavelet domain. The theoretical background is derived and Monte Carlo simulation is used to investigate the performance of the estimator. [ABSTRACT FROM AUTHOR]

The hidden Markov model (HMM) has been widely used in regime classification and turning point detection for econometric series after the decisive paper by Hamilton (Econometrica 57(2):357-384, ). The present paper will show that when using HMM to detect the turning point in cyclical series, the accuracy of the detection will be influenced when the data are exposed to high volatilities or combine multiple types of cycles that have different frequency bands. Moreover, outliers will be frequently misidentified as turning points. The present paper shows that these issues can be resolved by wavelet multi-resolution analysis based methods. By providing both frequency and time resolutions, the wavelet power spectrum can identify the process dynamics at various resolution levels. We apply a Monte Carlo experiment to show that the detection accuracy of HMMs is highly improved when combined with the wavelet approach. Further simulations demonstrate the excellent accuracy of this improved HMM method relative to another two change point detection algorithms. Two empirical examples illustrate how the wavelet method can be applied to improve turning point detection in practice. [ABSTRACT FROM AUTHOR]

For testing unit root in single time series, most tests concentrate on the time domain. Recently, Fan and Gençay (Econom Theory 26:1305-1331, ) proposed a wavelet ratio test which took advantage of the information from the frequency domain by using a wavelet spectrum methodology. This test shows a better power than many time domain based unit root tests including the Dickey-Fuller (J Am Stat Assoc 74:427-431, ) type of test in the univariate time series case. On the other hand, various unit root tests in multivariate time series have appeared since the pioneering work of Levin and Lin (Unit root test in panel data: new results, University of California at San Diego, Discussion Paper, ). Among them, the Im-Pesaran-Shin (IPS) (J Econ 115(1):53-74, ) test is widely used for its straightforward implementation and robustness to heterogeneity. The IPS test is a group mean test which uses the average of the test statistics for each single series. As the test statistics in each series can be flexible, this paper will apply the wavelet ratio statistic to give a comparison with the test by using Dickey-Fuller t statistic in the single series. Simulation results show a gain in power by employing the wavelet ratio test instead of the Dickey-Fuller t statistic in the panel data case. As the IPS test is sensitive to cross sectional dependence, we further compare the robustness of both test statistics when there exists cross correctional dependence among the units in the panel data. Finally we apply a residual based wavestrapping methodology to reduce the over biased size problem brought up by the cross correlation for both test statistics. [ABSTRACT FROM AUTHOR]

Graves' disease (GD) involves auto-immunity against thyroid cell antigens, but the reasons for the induction of auto-immunity are uncertain. We wished to investigate the role of T helper 17 (Th17) and regulatory T cells (Treg) in a mouse model of Graves' hyperthyroidism. The model was generated by immunizing mice with adenovirus expressing the autoantigen thyroid-stimulating hormone receptor (Ad-TSHR289). The frequencies of splenic Th17 and Treg were determined by flow cytometry. The levels of interleukin-17(IL-17), forkhead box P3 (Foxp3), and orphan retinoic acid nuclear receptor (RORγt) mRNA were determined by real-time PCR. The number of CD4CD25Foxp3 T lymphocyte was significantly reduced in the Ad-TSHR289 group compared with the Ad-control ( P < 0.05). mRNA level for Foxp3 was less abundant in Ad-TSHR289 group compared with Ad-control ( P < 0.05). However, CD4IL-17 T-cell subpopulation and expression of RORγt mRNA did not differ significantly between Ad-TSHR289 and Ad-control groups ( P > 0.05). Nevertheless, in Ad-TSHR289 group, a profound increase in the Th17/Treg ratios was found. The present study demonstrates that Th17 is not involved in promoting Graves' hyperthyroidism, while Treg and the ratio of Th17/Treg might play a role in the pathogenesis of Graves' hyperthyroidism. [ABSTRACT FROM AUTHOR]

Iodine is an essential trace element for thyroid hormone synthesis and metabolism, either low or high intake may lead to thyroid disease, but the pathogenetic mechanisms by which iodine interacts with the thyroid autoimmune are poorly understood. We investigated the dynamic changes of CD4CD25 regulatory T cells in NOD.H-2 mice with iodine-induced autoimmune thyroiditis (AIT), and explore potential immune mechanism of AIT induced by iodine. NOD.H-2 mice were randomly divided into two groups, and received plain water or water containing 0.005% sodium iodide. Eight weeks after iodine provision, the incidences of thyroiditis, relative weights of thyroids, and serum thyroglobulin antibody titers in the iodine-supplied groups were significantly increased compared to the control groups ( p < 0.05). The AIT mice had fewer CD4CD25Foxp3 T cells and reduced Foxp3 mRNA expression in splenocytes compared with the controls ( p < 0.01), and maintained relatively low levels during the development of thyroiditis. The changes described above aggravated gradually with the extension of iodine treatment. These data suggest that CD4CD25 regulatory T cells may be involved in the pathogenesis and development of AIT induced by iodine. [ABSTRACT FROM AUTHOR]

Graves’ disease (GD) was believed to be a polygenic disease. Several chromosomal regions were linked to GD, and the 5q31 chromosome regions containing several interleukin genes cluster were worth observing. In this study, IL4, IL13, IRF1 and UGRP1 genes were sequenced, and 5, 3, 7 and 7 polymorphisms respectively were discovered. Then an extended association study for the attracting polymorphisms was performed with 146 sporadic Graves’ patients, 142 unrelated controls and the 54 multiplex Graves’ families. However, the genotype and allele frequency distribution of these polymorphisms had similar distribution between the Graves’ patients and unrelated controls, and transmission disequilibrium tests indicated that none of them showed dominant transmission from heterozygous parents to the affected offsprings. Comparison of the clinical variables of the Graves’ patients indicated that the onset ages of the patients carrying TT at IRF1 6477 T/G locus were younger than those having variant allele (TG, GG); the difference was of statistical significance ( P=0.005, Pc=0.020). Our association study revealed that, IL4, IL13, IRF1 and UGRP1 genes in chromosomal 5q31 regions might not confer susceptibility to Chinese GD. But those individuals who were TT homozygous at IRF1 6477 T/G locus seemed to be attacked by GD much earlier than others. [ABSTRACT FROM AUTHOR]

It is widely accepted that the design of morphological filters, which are optimal in some sense, is a difficult task. In this paper a novel method for optimal learning of morphological filtering parameters (Genetic training algorithm for morphological filters, GTAMF) is presented. GTAMF adopts new crossover and mutation operators called the curved cylinder crossover and master-slave mutation to achieve optimal filtering parameters in a global searching. Experimental results show that this method is practical, easy to extend, and markedly improves the performances of morphological filters. The operation of a morphological filter can be divided into two basic problems including morphological operation and structuring element (SE) selection. The rules for morphological operations are predefined so that the filter's properties depend merely on the selection of SE. By means of adaptive optimization training, structuring elements possess the shape and structural characteristics of image targets, and give specific information to SE. Morphological filters formed in this way become certainly intelligent and can provide good filtering results and robust adaptability to image targets with clutter background. [ABSTRACT FROM AUTHOR]

This study investigates the intricate interplay of hydraulic coupling, creep damage, and permeability evolution mechanisms in phyllite, focusing on their relevance to tunnel engineering design and long-term stability in soft rock formations. To achieve this, conventional triaxial tests were conducted on saturated phyllite specimens under creep-seepage acoustic emission conditions. The results were systematically analyzed to unveil the inherent characteristics of creep deformation, seepage rate evolution, and damage progression in phyllite when subjected to stress–seepage coupling. Furthermore, a permeability model for representative volume element (RVE) was developed based on meso-mechanics principles, considering the distinctive attributes of low-permeability non-Darcy’s flow in rock. Consequently, a novel relationship between effective damage and permeability was established. We determined that seepage pressure induces three key effects on the creep damage mechanism of phyllite samples: (1) It adds to the existing stress through the superposition of osmotic pressure and axial load, (2) it induces tensile expansion stress because of pore water pressure, and (3) it softens the fracture surfaces to some extent. More importantly, this study validates the relationship between effective damage and permeability through the fitting of creep and damage parameters, which were obtained from the test results, and it reveals a square relationship between subsequent damage and permeability under stress conditions. The findings of this study provide a robust theoretical foundation for comprehending the evolution of damage and permeability characteristics during the creep process of rock under seepage conditions. We obtained essential insights and quantitative analyses for comprehending the damage mechanisms in rock creep under hydraulic coupling, which has significant implications for tunnel engineering and long-term rock stability assessments in soft rock environments. [ABSTRACT FROM AUTHOR]