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Deterioration of adhesively bonded CFRP/steel systems in salt fog environment, i.e., deicing salts and ocean environments, has to be taken into account in the design of steel strengthened structures. In the present work, monotonic and quasi-static cyclic loading were applied to CFRP-to-steel double strap joints for two kinds of CFRP laminates after being aged for a period of 5000 h to evaluate the bond behavior. The bonded joints exposed to salt fog had a different failure mode than that observed in the control specimens (0 h of exposure). The severe reduction of the maximum bond stress resulted from damage initiation that occurred in the corrosion region of the steel substrate, associated with final partial rupture on the corroded steel substrate around the edge of the bonded area: it was also correlated with reduced load carrying capacity. Results of pseudo-cyclic tests showed that the relationship between a local damage parameter (D) and normalized local dissipated energy (W d /G f) and the normalized slip increment (ΔS/ΔS ult) exhibited almost the same trend in the un-aged and aged bonded joints. The normalized slip increment can be seen as a direct indicator for the local and global damage for the un-aged and aged bonded joints. However, monotonic and quasi-static cyclic tests results revealed that the stress concentration due to local corrosion of steel substrate could lead to brittle rupture or accelerated cumulative damage once the aged bonded interface had become weaker. The bonded joints have exhibited also a smaller relative deformation capacity between CFRP and steel. [ABSTRACT FROM AUTHOR]

The bearing vibration of wind turbines is nonlinear and non-stationary. To effectively extract bearing vibration signal features for fault diagnosis, a method of feature vector extraction based on variational mode decomposition (VMD) and energy entropy is proposed. In addition, the support vector machine (SVM) classifier is used to identify the types of vibration faults. VMD transforms the constrained variational objective function into the unconstrained one to optimize solution. Compared with the VMD and empirical mode decomposition (EMD), the modal decomposition layer of VMD is less than EMD, no found false modality, and truly reflecting signal components. After the Hilbert transformation, double logarithmic coordinates show that the VMD-based spectral characteristics are significant. VMD is performed on the different types of vibration signals of wind turbines. Therefore, VMD is not that affected by noise and has few decomposition levels. The energy entropy of the normalized four modal components is considered the eigenvalue and classified by SVM, and compared with EMD-based and wavelet db4-based energy entropy eigenvalue extraction methods. Experimental results indicate that the accuracy of the method is higher than those based on EMD and wavelet db4, under the limited sample condition. Thus, a referential diagnostic method is provided for practical applications. • A method of feature vector extraction based on variational mode decomposition (VMD) and energy entropy is proposed. • The time-frequency energy spectrum obtained by VMD is compared with that by empirical mode decomposition (EMD). • Different types of bearing vibration signals of wind turbine are analyzed. • The fault diagnostic identification of the proposed method is compared with EMD-based and wavelet db4-based methods. [ABSTRACT FROM AUTHOR]

Abstract The degradation mechanisms of bonded joints between CFRP laminates and steel substrates under severe environmental conditions require more durability data and studies to increase the database and better understand their causes. Studies on bond properties of double-strap CFRP-to-steel bonded joints with two different composite materials as well as adhesive coupons subjected to freeze-thaw cycles for 10,000 h were conducted to reduce that gap. In addition, the equivalent to the number of thermal cycles and their slips induced in the CFRP laminates was replicated by an equivalent (mechanical) loading-unloading history condition imposed by a static tensile machine. The mechanical properties of the adhesive coupons and the strength capacity of the bonded joints were only slightly changed by the artificial aging. It was confirmed that the interfacial bond strength between CFRP and adhesive is critically related to the maximum shear stress and failure mode. The interfacial bond strength between adhesive and steel degraded with the aging. However, the equivalent thermal cyclic bond stress caused no detectable damage on the bond because only the interfacial elastic regime was actually mobilized, which confirmed that pure thermal cycles aging, per se , at the level imposed, have a low impact on the degradation of CFRP-to-steel bonded joints. [ABSTRACT FROM AUTHOR]

Lumen is a common anatomical condition in endoscopic therapy or diagnostics. The navigation of autonomous robotic endoscopy usually involves vision techniques such as detection of lumen center or anatomically specific contour features. However, these methods may fail to achieve smooth interventions and result in large conveying force without spatial awareness of the tissue state. In this paper, a novel navigation pipeline based on a spatial-aware monocular vision is proposed. The spatial awareness pipeline starts with a data-driven depth estimation technique for reconstructing real-time approximate tissue surface. The spatial shape of the lumen described by the skeleton is then extracted using digital topology. We modify the skeleton to get a smooth pathway, and design an adaptive autonomous control strategy using geometric information from the pathway. We conduct experiments on a colon phantom and ex vivo pig intestines. We test turning performance of several bending segments with different angles in phantom, as well as the overall performance of a long-range intervention task in the phantom and pig intestines. The results show our navigation scheme achieve smoother intervention with lower conveying force. The proposed navigation method with spatial awareness can effectively improve the fluency of autonomous robotic endoscopy. • Use explicit and implicit geometric consistency for endoscopic depth estimation. • Extract spatial pathway from depth map by digital topology method. • Utilize spatial information in adaptive control of autonomous robotic endoscopy. • Test autonomous endoscopy on digestive tract phantom and ex vivo pig intestines. [ABSTRACT FROM AUTHOR]

Monocular depth estimation is critical for endoscopists to perform spatial perception and 3D navigation of surgical sites. However, most of the existing methods ignore the important geometric structural consistency, which inevitably leads to performance degradation and distortion of 3D reconstruction. To address this issue, we introduce a gradient loss to penalize edge fluctuations ambiguous around stepped edge structures and a normal loss to explicitly express the sensitivity to frequently small structures, and propose a geometric consistency loss to spreads the spatial information across the sample grids to constrain the global geometric anatomy structures. In addition, we develop a synthetic RGB-Depth dataset that captures the anatomical structures under reflections and illumination variations. The proposed method is extensively validated across different datasets and clinical images and achieves mean RMSE values of 0.066 (stomach), 0.029 (small intestine), and 0.139 (colon) on the EndoSLAM dataset. The generalizability of the proposed method achieves mean RMSE values of 12.604 (T1-L1), 9.930 (T2-L2), and 13.893 (T3-L3) on the ColonDepth dataset. The experimental results show that our method exceeds previous state-of-the-art competitors and generates more consistent depth maps and reasonable anatomical structures. The quality of intraoperative 3D structure perception from endoscopic videos of the proposed method meets the accuracy requirements of video-CT registration algorithms for endoscopic navigation. The dataset and the source code will be available at https://github.com/YYM-SIA/LINGMI-MR. [ABSTRACT FROM AUTHOR]

Pseudo-cyclic and cyclic loading were applied to CFRP-to-steel bonded joints built with two different CFRP laminates. In this paper, the strength capacity and bond-slip curves are presented and compared. The modes of failure are also described and associated with the types of material used, and the observed performances are correlated. The analysis of the results showed a threshold value for loading and amplitude level, below which the cyclic loading caused no detectable damage. For cycles above that limit, the region of the joints around the loaded end presented degradation reflected on the bond-slip stiffness and on the increase of residual deformation. It was found that the normalized dissipated energies either obtained from the bond-slip relationship or from the load-slip response had the same trend. The experimental data allowed also to establish a relationship between the damage developed within the interface and the normalized slip. A preliminary estimate of fatigue limit based on those data is suggested. [ABSTRACT FROM AUTHOR]

Highlights • We propose a robust one-shot three-dimensional imaging method based on image processing. • We propose a top to bottom clustering algorithm to cluster the continuous lines robustly. • We propose a phase map computation method based on the clustered lines. Abstract Reconstruction of the object by single-shot is of great importance in many applications, in which the object is moving or its shape is non-rigid and changes irregularly. In this paper, we propose a single-shot structured light 3D imaging technique that calculates the phase map from the distorted line pattern. This technique makes use of the image processing techniques to segment and cluster the projected structured light line pattern from one single captured image. The coordinates of the clustered lines are extracted to form a low-resolution phase matrix which is then transformed to full-resolution phase map by spline interpolation. The 3D shape of the object is computed from the full-resolution phase map and the 2D camera coordinates. Experimental results show that the proposed method was able to reconstruct the three-dimensional shape of the object robustly from one single image. [ABSTRACT FROM AUTHOR]

Transformer is an important equipment for power energy transmission. The vibration and noise of transformer have always been a serious issue of people concern. Transformer body vibration and noise are mainly caused by the global magnetization of limbs and yokes and magnetic forces of transformer core. However, the process of vibration transfer from core to body is a key factor for monitoring the transformer condition. In this paper, a transformer model for vibration transmission is presented based on motion transmission and it can be used to analyze the vibration relation between core and shell of transformer. Considering strain of silicon steel as the vibration source, the motion equations whichexpress the relations of transformer core and shell are derived. And then, the test system is built to analyze the vibrations of a 5 kVA three phase transformer. A 3D real model simulation used COMSOL finite element software is performed for analyzing the deformation characteristic of transformer. The locations of test points which reflect the vibration more efficiently are determined through the deformation simulation results. Lastly, the vibration signals of two directions have been measured considering DC magnetic bias or not. The experimental results reveal that vibration relations between core and shell are satisfied with the theoretical derivation. Therefore, the Vibration Transmission is significant and it can provide valid method for the DC magnetic bias analysis and core diagnosis of transformer. [ABSTRACT FROM AUTHOR]

Partial discharge (PD) is one of the main diagnosis methods for the insulation aging of large motors. A data compression denoising method based on the empirical mode decomposition (EMD) algorithm is proposed according to the weak and large disturbances of large motor PD signals. A simulation model is constructed to verify the effectiveness of the proposed algorithm. Furthermore, the denoising effect of the proposed algorithm is compared with that of the db2 and db8 wavelets in the experiments. The simulation and experimental results show that a data compression denoising algorithm based on EMD can achieve the same denoising effect with those based on db2 and db8 wavelets. The proposed algorithm is even better in terms of relative error and mean square error. For actual signal processing, the data compression denoising algorithm is better than the other algorithms and does not lose the original signal energy. The PD ultrasonic signals are spectrally analyzed by using HHT, and signal energy distribution in time and frequency can be clearly described. The main PD ultrasonic signal characteristics can be extracted currently from the marginal and Hilbert spectra. The results of this study will be helpful for the diagnosis of PD faults in large motors. [ABSTRACT FROM AUTHOR]

Carbon Fiber Reinforced Polymer (CFRP) composites have a large potential for strengthening and retrofitting steel parts but due to their premature debonding from steel, further data and research are still required for wider application in such situations. In the present paper, the bond characteristics of CFRP-to-steel joints in pull-pull loaded conditions were studied. Monotonic loading of the double strap joints with different bond lengths was applied and the failure modes and interfacial bond-slip curves were obtained. A tri-linear bond-slip model is proposed and it was derived from the experimental data. A closed-form solution approach is also proposed based on the tri-linear bond-slip model. The strength of the CFRP-to-steel interface, the distribution of the relative displacements between bonded materials, the strains developed in the CFRP laminate and the bond stresses along the interface are reported and the closed-form solution is compared with the experimental results. Two cases are selected for presentation: (i) one with the bond length greater than the effective bond length; and, inversely, (ii) one with bond length which is shorter than the effective bond length. The results predicted by the closed-form solutions are shown to be accurate enough when compared to the experiments. [ABSTRACT FROM AUTHOR]

A series of triaxial compression and microfocus CT scanning tests of tight reservoir sandstone were implemented to investigate its three-dimensional (3D) crack propagation behavior. The 3D geometric morphology and distribution characteristics of the cracks under various triaxial stresses were studied. Three-dimensional reconstruction models of the crack morphology were established and the influences of confining pressures on crack propagation were probed. The fractal theory was used to describe the rough morphology of the crack surfaces. The energy mechanism that governs crack growth was analyzed using the energy theories and principles. Energy dissipation and energy release laws were proposed to characterize crack growth under various triaxial stresses. The results indicate that triaxial stress has a great effect on the quantity, geometry and spatial distribution features of cracks. In the fractured sandstone sample, a lower confining pressure induces numerous macroscopic cracks accompanied by microcracks; they interconnect to form an intricate crack network. In contrast, a higher confining pressure results in a small number of macroscopic cracks whose surfaces present a simple geometry, similar to a plane surface. The fractal dimension of crack surfaces decreases linearly with the increase in confining pressure. Meanwhile, the releasable elastic strain energy rises and the dissipated energy density decreases linearly when increasing the confining pressure. [ABSTRACT FROM AUTHOR]

Fiber reinforced polymer (FRP) composites with anhydride cured epoxy resin matrices are widely used in civil engineering (e.g., pultruded FRP plates and bars), and their thermal aging behavior is a concern when they are subjected to elevated temperatures (e.g., FRP chimney). In the present article, thermal aging of an epoxy resin matrix at 130 °C–160 °C for 30 days was performed, and the effects on the flexural properties, molecular structures, free volume fraction, and mechanical properties were investigated. FTIR spectroscopy indicated that oxidation and molecular rearrangement occurred in the skin of the epoxy samples during thermal aging. Dynamic mechanical thermal analysis (DMTA) further illustrates the dominant effect of the molecular rearrangement in the sample skin with a thickness less than 100 μm, leading to a new high temperature tan δ peak. The free volume fraction of the skin and the bulk epoxy sample was characterized by positron annihilation lifetime spectroscopy (PALS). The results indicate that a noticeable reduction of the apparent free volume fraction occurred in the sample skin, while the bulk sample was only slightly affected. The flexural results indicate that thermal aging obviously reduced the break strain, while the flexural strength was only slightly affected and the modulus increased. [ABSTRACT FROM AUTHOR]

In this paper, the influence of salt fog and ambient condition exposure on CFRP-to-steel bonded joints (CSJs) with a near end mechanical anchorage was studied. The tests of the CSJs were carried out with a monotonic loading history respectively with and without a near end mechanical anchorage both unaged and after being exposed to the ageing conditions. The results revealed failures in the adhesive for some CSJs with a near end mechanical anchorage, among which also exhibited the best bond performance both in aged and unaged specimens. Due to the high state of degradation after ageing exposure, local damage of the CFRP located at the gap position of the CSJs was induced by a torsion action during the fixation of the specimen in the tensile machine even prior to the testing, which caused, although locally, severe delamination of the CFRP of the aged CSJs. From the torsion test results, a decrease in the torsional capacity of the CFRP after aging revealed the degradation of the carbon fiber-to-matrix interface. Additional results reflected that a drop in the initial stiffness of the load vs. slip relationship can be observed, caused by a pre-crack with a length of 30 mm in the CSJs. [ABSTRACT FROM AUTHOR]

Abstract: We describe ultrasound-guided establishment of hip arthroscopy portals. The surface projections of anatomic structures around the hip joint (including the nerve, vessels, femoral neck, and acetabulum) were marked. The entry points were then planned for the anterolateral and anterior portals and, if necessary, the posterolateral portal. The anterolateral portal was first placed. Through the use of real-time ultrasound guidance, a pin was inserted into the hip joint and 20 mL of normal saline solution was injected. A K-wire was then inserted into the joint space over the needle. The arthroscopic trocar was introduced along the K-wire, and the arthroscope was inserted to confirm the establishment. The anterior portal was then established. The hip joint was flexed slightly. The previous procedure was duplicated to insert the K-wire. The path of the pin was confirmed by viewing from the arthroscope in the anterolateral portal. If necessary, the posterolateral portal was established by the same procedure. [Copyright &y& Elsevier]

Mechanical anchorage devices have the potential to efficiently improve the bond behavior of Carbon Fiber-Reinforced Polymers (CFRP) Externally Bonded (EB) onto steel with an adhesive. Existing relevant studies, however, have been very limited. Against this background, experimental and numerical studies on the double overlapped CFRP-to-steel bonded joints with an end mechanical anchorage were carried out in the present study. Two types of CFRP laminates (i.e. , SIKA CFRP and the other type made in Harbin Institute of Technology – HIT) were used in the bond tests, with or without end mechanical anchorage devices. The test results showed that the end mechanical anchorage had marginal effect on the bond-slip relationship between EB CFRP and steel as well as debonding load, but could increase the ultimate load. It was also found that CFRP laminate from HIT had a better bond performance than that from SIKA, in terms of both debonding load and ultimate load. Using ABAQUS, Finite Element (FE) model was established on such bonded joints and the accuracy was verified with test results. The verified FE model was adopted in a parametric study to further clarify the effect of key parameters on the bond behavior of such bonded joints. [ABSTRACT FROM AUTHOR]

Effects of salt fog on CFRP-steel bonded joints were studied via simulation by accelerated cycles. CFRP-to-steel double strap joints made of two different types of laminates were subjected to salt fog cycles for 5000 h and Mode-II tests conducted to assess the degradation of their bond capacity at selected time stages of the process. Different mechanisms causing strength losses were found and analyzed. Results showed that the bond capacity of joints increased initially but was reduced at later stages. Corrosion debonding took place in the chamber between 5,000 h and 10,000 h prior to the application of external loading. Combined Attenuated Total Reflectance-Fourier transform infrared (FTIR) spectroscopy and Dynamic Mechanical Analysis (DMA) results showed that severe degradation at the interface of carbon fibers and resin only took place for one type of laminate. Galvanic corrosion was also analyzed and coupling between CFRP and steel developed due to the corrosion product depositions over the components leading to the degradation of the same type of laminate. [ABSTRACT FROM AUTHOR]

Utilizing ductile adhesive on CFRP-reinforced steel structures makes the bonded interface with good resistance to dynamic and fatigue loading, which is suitable for the rehabilitation of steel bridges. Currently, considerable studies on the aspect of the CFRP–steel interface are focused only on mode-II loading, ignoring the effects of mode-I loading which could lead to a catastrophic collapse of the retrofitted structures. In the present paper, modified CFRP-to-steel bonded double overlapped joints with various initial peeling angles (θ) were manufactured in order to consider mode-I loading and study the bond behavior of CFRP-to-steel joints under mixed mode-I&II loading. The results showed that the bonded side with weaker adhesion between CFRP and adhesive debonded first and presented a CFRP-adhesive interfacial debonding mode, while the debonding of the other side was delayed and showed a cohesive failure mode in the adhesive. The bond shear stress vs. slip relationship of the debonded side showed to have a bi-linear trend in which the bond strength and interfacial fracture energy were low whilst the other side showed a trapezoidal relationship with a constant plastic plateau and with higher interfacial fracture energy. It was found that sudden debonding caused a quick propagation in the CFRP strain as well as on the global interfacial slip of the joints. It was also found that the peeling angle had significantly deteriorated the local bond response in mode-II, i.e. the trapezoidal bond shear stress vs. slip relationship in the joints with θ = 0 ° shifted to a bi-linear relationship in the joints with θ = 1 ° , θ = 2 ° and with θ = 3 ° in which the bond strength, slip and fracture energy, all decreased very much. Moreover, with θ = 4 ° was experimentally determined as the threshold angle from which the associated mode-I loading can, per se , separate the CFRP from steel. • A review of the bond behavior of CFRP-to-steel joints subjected to mode-I, mode-II and mixed mode-I&II loading is presented. • Modified CFRP-to-steel bonded joints were conceived, allowing assessment of the bond behavior considering mode-I loading. • Different bond qualities in both sides of the CFRP-to-steel double overlapped joints were identified. • Influences of the initial peeling angles on the bond performance of the CFRP-to-steel joints were analyzed thoroughly. • Degradation of bond shear stress vs. slip response due to mode-I loading was experimentally observed. [ABSTRACT FROM AUTHOR]

A quantification method for evaluation of the fracability of shale is essential for optimizing hydraulic fracturing of shale gas reservoirs and enhancing shale gas recovery. To quantitatively evaluate the fracability, seven sets of shale cores are drilled from the reservoirs at different depths of an oilfield in the east of China. The influences of six fracability-related mechanical and physical characteristics of shale, i.e. brittleness, brittle mineral content, clay mineral content, cohesion, angle of internal friction, and unconfined compressive strength, are analyzed. A mathematical model taking account of significance of the influencing factors is proposed based on analytic hierarchy process (AHP) to evaluate the fracability according to their different effects on shale fracability. The analysis indicates that the fracability decreases with the increase of reservoir depths. The hydraulic fracturing tests of the shale cores are conducted to verify the accuracy of the quantification method. The fractal geometry is used to characterize the fracture degree of the shale. It is shown that a larger fractal dimension of the fracture network corresponds to a better fracability of shale. The more complex the fractures are, the larger the fracability of shale is. The experimental data coincide with the results of the proposed evaluation model. [ABSTRACT FROM AUTHOR]

Despite the rapid technical advancement of augmented reality (AR) and mixed reality (MR) in minimally invasive surgery (MIS) in recent years, monocular-based 2D/3D reconstruction still remains technically challenging in AR/MR guided surgery navigation nowadays. In principle, soft tissue surface is smooth and watery with sparse texture, specular reflection, and frequent deformation. As a result, we frequently obtain only sparse feature points that give rise to incorrect matching results with conventional image processing methods. To ameliorate, in this paper we enunciate an accurate and robust description and matching method for dense feature points in endoscopic videos. Our new method first extracts contours of the low-rank image sequences based on the adaptive robust principal component analysis (RPCA) decomposition. Then we propose a multi-scale dense geometric feature description approach, which simultaneously extracts dense feature descriptors of the contours in the original Euclidean coordinate space, the accompanying 3D color coordinate space, and the derived curvature-gradient coordinate space. Finally, we devise a new algorithm for both global and local point-wise matching based on feature fusion. For global matching, we employ the fast Fourier transform (FFT) to reduce the dimension of the dense feature descriptors. For local feature point matching, in order to enhance the robustness and accuracy of the matching, we cluster multiple contour points to form "super-point" based on dense feature descriptors and their spatio-temporal continuity. The comprehensive experimental results confirm that our novel approach can overcome the highlight influence, and robustly describe contours from image sequences of soft tissue surfaces. Compared with the state-of-the-art feature point description and matching methods, our analysis framework shows the key advantages of both robustness and accuracy in dense point-wise matching, even when the severe soft tissue deformation occurs. Our new approach is expected to have high potential in 2D/3D reconstruction in endoscopy. [Display omitted] • Accurate and robust contour description for soft tissue. • Multi-scale, dense, and hybrid geometric feature descriptors in endoscopic images. • Global and local point-wise feature point matching. • Our method overcomes the problems of highlight and sparse texture in feature extraction, and demonstrates its potential applications in 2D/3D reconstruction for endoscopy. [ABSTRACT FROM AUTHOR]

• A passively mode-locked EDF laser using an Sb 2 S 3 -PVA SA. • Evolution of multiple pulses from onefold to sixfold pulses. • Pump hysteresis phenomenon. • Relationship of RF modulation period and pulse interval of multi-pulse bunch. The evolution of multiple pulses and the pump hysteresis phenomenon were observed in a passively mode-locked Er-doped fiber laser using an Sb 2 S 3 -PVA saturable absorber. As the pump power was increased, the generations of onefold, twofold and threefold pulses were meticulously documented. When the pump power was decreased, the evolution of fivefold and sixfold pulses was carefully recorded, accompanied by a clear pump hysteresis phenomenon. A thorough analysis was conducted to examine and reveal the inversely proportional relationship between the RF spectrum modulation periods and the total pulse intervals of the multi-pulse bunches including from onefold to sixfold pulses. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the therapeutic effect of Cordyceps sinensis -derived fungus Isaria felina on experimental autoimmune thyroiditis (EAT). A NaI-induced EAT mouse model was established. The mice received oral administration of vehicle, low-dose Isaria felina (300 mg/kg), or high-dose Isaria felina (600 mg/kg) once a day for four weeks before euthanasia. Enzyme-linked immunosorbent assays (ELISA) was performed to measure serum thyroid-stimulating hormone (TSH) levels, thyroid antibodies, and cytokines. Hematoxylin and eosin (H&E) staining was conducted to assess histopathological changes in the thyroid tissue samples of mice. TUNEL and Bcl-2 immunohistochemistry (IHC) were performed to evaluate cell apoptosis, and cleaved caspase-3 IHC was performed to detect the relative expression in the thyroid tissue samples. Compared with KIO 3 and KI water, NaI water consumption successfully induced EAT in mice, as evidenced by significantly increased circulating TSH and thyroid antibody levels, along with typical histopathological abnormalities of autoimmune thyroiditis (AIT) in the thyroid tissue samples. Compared with vehicle or low-dose Isaria felina , high-dose Isaria felina treatment resulted in significant reductions in white cell counts and circulating TSH, thyroid antibody, and cytokine levels of EAT mice. High-dose Isaria felina also alleviated histopathological abnormalities and attenuated TUNEL staining, Bcl-2 protein expression, and cleaved caspase-3 expression in the thyroid tissue samples. High-dose Isaria felina treatment alleviates thyroid inflammation and cell apoptosis in EAT, serving as a novel, promising therapeutic agent for AIT. • Isaria felina treatment alleviates thyroid inflammation and cell apoptosis in EAT. • Isaria felina ameliorates experimental autoimmune thyroiditis in mice. • Excess NaI for the long-term leads to an autoimmune thyroiditis model in mice. [ABSTRACT FROM AUTHOR]