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Background: Multiple sclerosis (MS) is the most common non-traumatic disabling disease. Objective: The aim of this study is to investigate the ability of radiomics features for diagnosing active plaques in patients with MS from T2 Fluid Attenuated Inversion Recovery (FLAIR) images. Material and Methods: In this experimental study, images of 82 patients with 122 MS lesions were investigated. Boruta and Relief algorithms were used for feature selection on the train data set (70%). Four different classifier algorithms, including Multi-Layer Perceptron (MLP), Gradient Boosting (GB), Decision Tree (DT), and Extreme Gradient Boosting (XGB) were used as classifiers for modeling. Finally, Performance metrics were obtained on the test data set (30%) with 1000 bootstrap and 95% confidence intervals (95% CIs). Results: A total of 107 radiomics features were extracted for each lesion, of which 7 and 8 features were selected by the Relief method and Boruta method, respectively. DT classifier had the best performance in the two feature selection algorithms. The best performance on the test data set was related to Boruta-DT with an average accuracy of 0.86, sensitivity of 1.00, specificity of 0.84, and Area Under the Curve (AUC) of 0.92 (95% CI: 0.92-0.92). Conclusion: Radiomics features have the potential for diagnosing MS active plaque by T2 FLAIR image features. Additionally, choosing the feature selection and classifier algorithms plays an important role in the diagnosis of active plaque in MS patients. The radiomics-based predictive models predict active lesions accurately and non-invasively.

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A biosensor based on glutamate oxidase (GluOx) was developed to measure glutamate concentration. The main function of this type of biosensor is related to the structure and catalytic activity of GluOx. Since radiofrequency, as the widest spectrum of electromagnetic fields, can affect the catalytic activity and structure of GluOx, in this study, the effect of these fields on the analytical parameters of the fabricated biosensor was investigated. To build the biosensor a sol-gel solution of chitosan and native GluOx were prepared and then immobilized on the surface of the platinum electrode. Similarly, to investigate the effect of radiofrequency fields on the analytical parameters of the biosensor, instead of the native GluOx, irradiated GluOx was used to build the biosensor. To evaluate the biosensor responses, cyclic voltammetry experiments were performed and voltammograms were considered as biosensor responses. To determine the analytical parameters including detection limit, linear range, and saturation region of the responses, calibration curves were drawn for each of the biosensors. Also the long-term stability and selectivity of the fabricated biosensor were evaluated. Thereafter, the optimum pH and temperature for each of these two biosensors were examined. The results showed that radiofrequency waves harmed the detection and response of biosensors in the saturation region, while they had little effect on the linear region. Such results could be due to the effect of radiofrequency waves on the structure and function of glutamate oxidase. In general, the results indicate that when a glutamate oxidase-based biosensor is used to measure glutamate in radiofrequency fields, corrective coefficients for this type of biosensor should be considered to accurately measure glutamate concentration.

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Repetitive transcranial magnetic stimulation (rTMS), often recognized as a safe and tolerable method with promising therapeutic potential for the treatment of a variety of neurological disorders, has been extensively studied by medical engineering scientists in recent decades. Epilepsy has always been one of the vital foci in the therapeutic role of rTMS, especially its low-frequency type. However, various reports, clinical trials, and review articles published in recent years have yielded conflicting results regarding the efficacy and side effects of rTMS in patients. In this review article, reviewing studies published from January 2000 to October 2021, we examined the efficacy and side effects of rTMS with a specific look at its therapeutic applications in epilepsy. Our study indicates promising results in the clinical application of this technique for patients with epilepsy. Among other things, it has the ability to reduce interictal epileptic abnormalities, does not interfere with neuropsychological function in normal people, does not worsen cognitive function and even improves Stroop function, rarely has serious side effects such as seizures and psychotic symptoms, has low risk in children as adults, and has potential for improving suicidal ideation. Despite some limitations in this study, including the small number of studies performed and the heterogeneity among studies, this review article suggests significant rtMS potentials in improving the complications of epilepsy. Our review also showed that the reported side effects of using this technique are not very common. Therefore, we can recommend further use of this technique as a promising tool in clinical research.

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OBJECTIVES: To employ different automated convolutional neural network (CNN)-based transfer learning (TL) methods for both binary and multiclass classification of Alzheimer's disease (AD) using brain MRI. METHODS: Herein, we applied three popular pre-trained CNN models (ResNet101, Xception, and InceptionV3) using a fine-tuned approach of TL on 3D T1-weighted brain MRI from a subset of ADNI dataset (n = 305 subjects). To evaluate power of TL, the aforementioned networks were also trained from scratch for performance comparison. Initially, Unet network segmentedthe MRI scans into characteristic components of gray matter (GM), white matter (WM), and cerebrospinal fluid (CSF). The proposed networks were trained and tested over the pre-processed and augmented segmented and whole images for both binary (NC/AD + progressive mild cognitive impairment (pMCI)+stable MCI (sMCI)) and 4-class (AD/pMCI/sMCI/NC) classification. Also, two independent test sets from the OASIS (n = 30) and AIBL (n = 60) datasets were used to externally assess the performance of the proposed algorithms. RESULTS: The proposed TL-based CNN models achieved better performance compared to the training CNN models from scratch. On the ADNI test set, InceptionV3-TL achieved the highest accuracy of 93.75% and AUC of 92.0% for binary classification, as well as the highest accuracy of 93.75% and AUC of 96.0% for multiclass classification of AD on the whole images. On the OASIS test set, InceptionV3-TL outperformed two other models by achieving 93.33% accuracy with 93.0% AUC in binary classification of AD on the whole images. On the AIBL test set, InceptionV3-TL also outperformed two other models in both binary and multiclass classification tasks on the whole MR images and achieved accuracy/AUC of 93.33%/95.0% and 90.0%/93.0%, respectively. The GM segment as input provided the highest performance in both binary and multiclass classification of AD, as compared to the WM and CSF segments. CONCLUSION: This study demonstrates the potential of applying deep TL approach for automated detection and classification of AD using brain MRI with high accuracy and robustness across internal and external test data, suggesting that these models can possibly be used as a supportive tool to assist clinicians in creating objective opinion and correct diagnosis. ADVANCES IN KNOWLEDGE: We used CNN-based TL approaches and the augmentation techniques to overcome the insufficient data problem. Our study provides evidence that deep TL algorithms can be used for both binary and multiclass classification of AD with high accuracy.

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Introduction: Today, humans live in a world surrounded by electromagnetic fields. Numerous studies have been conducted to discover the biological, physiological, and behavioral effects of electromagnetic fields on humans and animals. Given the biological similarities between monkeys and humans, The present research aimed to examine Visual Memory (VM), hormonal, genomic, and anatomic changes, in the male rhesus macaques exposed to an Extremely Low-Frequency Magnetic Field (ELF-MF). Methods: Four male rhesus macaques (Macaca mulatta) were used. For the behavioral tests, the animals should be fasting for 17 hours. For the tests such as visual memory, the animal's cooperation was necessary. Using the radiation protocol, we exposed two monkeys to a 12-Hz electromagnetic field with a magnitude of 0.7 µT (electromagnetic radiation) four hours a day for a month. Before and after the exposure, a visual memory test was conducted using a coated device (visible reward) on a movable stand. Ten milliliters of blood was obtained from the femoral artery of each monkey, and half of it was used to examine cortisol serum levels using the MyBioSource kit (made in the USA). The other half of the blood was used to extract lymphocytes for assaying expressions of Glucocorticoid Receptor (GR) genes before and after radiation using the PCR method. Anatomic studies of the amygdala were carried out based on pre- and post-radiation Magnetic Resonance Imaging (MRI). Results: Research results indicated that visual memory in male primates increased significantly after exposure to the 12-Hz frequency. Hormonal analysis at the 12-Hz frequency showed a decrease in cortisol serum levels. However, visual memory and serum cortisol levels did not change considerably in male primates in the control group. There was no considerable amygdala volumetric difference after exposure to the 12-Hz frequency. The expression of the GR genes decreased in the 12-Hz group compared to the control group. Conclusion: In short, these results indicated that ELF might benefit memory enhancement because exposure to the 12-HZ ELF can enhance visual memory. This outcome may be due to a decrease in plasma cortisol and or expression of GR genes. Moreover, direct amygdala involvement in this regard cannot be recommended. Highlights: The effects of Extremely Low-Frequency Electromagnetic Fields (ELF-EMF) of 12 Hz on monkeys were studied.The results showed a reduction in the serum cortisol levels and the expression of GR genes.The amygdala anatomical area changes were not significant in the experimental group.In the experimental group, visual memory (delay of 30- and 60-s evaluation) improved after exposure to a frequency of 12 Hz. Plain Language Summary: Extremely low-frequency electromagnetic fields are among the most important factors affecting humans. This study aimed to determine the fields of 12-Hz frequency on the visual memory changes of male monkeys. The importance of research is due to the cognitive similarity of monkeys to humans. The findings of the research can be attributed to humans. Behavioral, hormonal, genetic, and anatomical studies indicated improvement in visual memory (test monkeys versus control monkeys). This study demonstrates the effect of the 12-Hz frequency on the monkey's visual memory. Researchers can study 12-Hz frequency in other cognitive indices.

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PURPOSE: Radiofrequency (RF) ablation therapy is of great interest in cancer therapy as it is non-ionizing radiation and can effectively penetrate into the tissue. However, the current RF ablation technique is invasive that requires RF probe insertion into the tissue and generates a non-specific heating. Recently, RF-responsive nanomaterials such as gold nanoparticles (AuNPs) and iron oxide nanoparticles (IONPs) have led to tremendous progress in this area. They have been found to be able to absorb the RF field and induce a localized heating within the target, thereby affording a non-invasive and tumor-specific RF ablation strategy. In the present study, for the first time, we used a hybrid core-shell nanostructure comprising IONPs as the core and AuNPs as the shell (IO@Au) for targeted RF ablation therapy. Due to the magnetic core, the nanohybrid can be directed toward the tumor through a magnet. Moreover, IONPs enable the nanohybrid to be used as a magnetic resonance imaging (MRI) contrast agent. RESULTS: In vitro cytotoxicity experiment showed that the combination of IO@Au and 13.56-MHz RF field significantly reduced the viability of cancer cells. Next, during an in vivo experiment, we demonstrated that magnetically targeting of IO@Au to the tumor and subsequent RF exposure dramatically suppressed the tumor growth. CONCLUSION: Therefore, the integration of targeting, imaging, and therapeutic performances into IO@Au nanohybrid could afford the promise to improve the effectiveness of RF ablation therapy.

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BACKGROUND: Traumatic diaphragmatic injury is known to present with the spectrum of symptoms, and most patients would have some symptoms due to abdominal organ herniation. Majority of injuries tend to present on the left hemidiaphragm but right-sided injuries also occur mostly with subtle, delayed presentation due to the buffering effect of the liver. CASE PRESENTATION: A 65-year-old male presented to the emergency department with a complaint of nausea and vomiting and reported no bowel movement or passing of flatus for 5 days. Upon further questioning, he recalled that he fell from a tractor while working in his farm 2 months earlier and sustained blunt trauma to his abdomen. Both chest and abdominal X-rays revealed the niveau formation of the small intestine on the right side above the liver and right hemidiaphragm. Further evaluation with CT scan confirmed the presence of a few small intestinal loops behind the liver and also in the chest through a rupture in the right hemidiaphragm. Exploratory laparotomy was performed. Some small intestine loops had gone behind the liver and through 4 cm rupture in the posterior aspect of the diaphragm into the chest. Displaced intestinal loops were relocated and no sign of ischemia or necrosis was observed. The patient was symptom-free within 2 days and he was discharged after 4 days. CONCLUSION: Traumatic injuries of the diaphragm are rare, yet underestimated; therefore, they need a high index of suspicion for timely diagnosis and neglected diagnosis may present with a range of symptoms such as herniation months to years later.

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OBJECTIVES: In the present study the effect of stress on monkeys that had learned to retrieve food from a five-chamber receptacle, as well as the relationship between their behavior and the serum cortisol and epinephrine levels and relative size of the amygdala was evaluated. MATERIALS AND METHODS: Six male rhesus monkeys were individually given access to the food reward orderly. They could easily retrieve the rewards from all chambers except for the chamber 4, which a brief, mild electric shock (3 V) was delivered to them upon touching the chamber's interior. The coping behaviors were video-recorded and analyzed offline. Baseline serum cortisol and epinephrine levels were measured before the experiments using monkey enzyme-linked immunosorbent assay kit. One week after the behavioral experiment, the monkeys' brains were scanned using magnetic resonance imaging under general anesthesia. The cross-sectional area of the left amygdala in sagittal plane relative to the area of the whole brain in the same slice was evaluated by the planimetric method using ImageJ software. RESULTS: Exposure to the distressing condition caused different behavioral responses. Monkeys with higher baseline levels of serum cortisol and epinephrine and larger amygdala behaved more violently in the face of stress, indicating adopting emotion-focused stress-coping strategies. Conversely, those with low plasma epinephrine, moderate cortisol, and smaller amygdala showed perseverative behavior, indicating a problem-focused coping style. CONCLUSION: In dealing with the same stress, different responses might be observed from nonhuman primates according to their cortisol and epinephrine levels as well as their amygdala dimensions.

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H2O2 generated during water radiolysis was measured electrochemically as an alternative dosimetry method. A biosensor was fabricated by immobilising modified horseradish peroxidase (HRP) on a glassy carbon electrode (GCE) followed by evaluation of its analytical parameters. Anthraquinone 2-carboxylic acid was used to modify HRP. To assess sensor performance, phosphate buffer solutions were irradiated with 0.510 Gy of gamma ray emitted from (60)Co. The results showed that this sensor can detect low quantities of hydrogen peroxide in water radiolysis. Sensitivity, detection limit and linear range of the biosensor were 260 nA/Gy, 0.392 Gy and 0.5-5 Gy, respectively. Long term stability studies showed that sensor responses were stable for at least a month. The cathodic peak current, as biosensor response, subsequently decreased to 20% of its initial value.

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Studies have demonstrated that electromagnetic waves, as the one of the most important physical factors, may alter cognitive and non-cognitive behaviors, depending on the frequency and energy. Moreover, non-ionizing radiation of low energy waves e.g. very low frequency waves could alter this phenomenon via alterations in neurotransmitters and neurohormones. In this study, short, medium, and long-term exposure to the extremely low frequency electromagnetic field (ELF-EMF) (1 and 5 Hz radiation) on behavioral, hormonal, and metabolic changes in male Wistar rats (250 g) were studied. In addition, changes in plasma concentrations for two main stress hormones, noradrenaline and adrenocorticotropic hormone (ACTH) were evaluated. ELF-EMF exposure did not alter body weight, and food and water intake. Plasma glucose level was increased and decreased in the groups which exposed to the 5 and 1Hz wave, respectively. Plasma ACTH concentration increased in both using frequencies, whereas nor-adrenaline concentration showed overall reduction. At last, numbers of rearing, sniffing, locomotor activity was increased in group receiving 5 Hz wave over the time. In conclusions, these data showed that the effects of 1 and 5 Hz on the hormonal, metabolic and stress-like behaviors may be different. Moreover, the influence of waves on stress system is depending on time of exposure.

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Growth arrest DNA damage-inducible 45a gene (Gadd45a) and immediate early response gene 5 (Ier5) have been emphasised as ideal radiation biomarkers in several reports. However, some aspects of radiation-induced transcriptional alterations of these genes are unknown. In this study, gender-dependency and dose-dependency as two factors that may affect radiation-induced transcription of Gadd45a and Ier5 genes were investigated. Human lymphocyte cells from six healthy voluntary blood donors (three women and three men) were irradiated in vitro with doses of 0.5-4.0 Gy from a (60)Co source and RNA isolated 4 h later using the High Pure RNA Isolation Kit. Dose and gender dependency of radiation-induced transcriptional alterations of Gadd45a and Ier5 genes were studied by quantitative real-time polymerase chain reaction. The results showed that as a whole, Gadd45a and Ier5 gave responses to gamma rays, while the responses were independent of radiation doses. Therefore, regardless of radiation dose, Gadd45a and Ier5 can be considered potential radiation biomarkers. Besides, although radiation-induced transcriptional alterations of Gadd45a in female and male lymphocyte samples were insignificant at 0.5 Gy, at other doses, their quantities in female samples were at a significantly higher level than in male samples. Radiation-induced transcription of Ier5 of females samples had a reduction in comparison with male samples at 1 and 2 Gy, but at doses of 0.5 and 4 Gy, females were significantly more susceptible to radiation-induced transcriptional alteration of Ier5.

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The Iranian Registry of Clinical Trials (IRCT) was established as a primary registry on December 4 2008 and has registered over 1350 trials by June 2011. Many researchers are still unaware of the need for registration of trials before recruiting the first patient and the proportion of retrospectively registered trials is likely to grow until this awareness increases. We sought to investigate the timing of the registrations in IRCT and to explore strategies to overcome this. We used all data in the IRCT database and extracted the date of registration, as well as the dates for the start and the end of recruitment. We categorized trials into 4 groups: those registered before the start of patient enrolment, within 30 days of enrolment, after 30 days but before the end of recruitment, and after the end of recruitment. The proportion of trials in each category was calculated by calendar year. The number of registered trials increased from 26 in the 3 months leading to 2009 to 181 in 2009, 772 in 2010 and 376 in the first 5 months of 2011 (estimate by end of year = 947). The proportions of trials registered after the end of patient recruitment were 55%, 58% and 62% in 2009, 2010 and 2011 respectively. On average, 6.4% of trials were registered within 30 days from the start of patient recruitment and 27% in the time between then and the end of recruitment. The rapid increase in the number of registered trials is an indication of strong implementation of the registration policy. This comes partly at the expense of an increased proportion of retrospective registrations. While this may be understandable at the beginning, it is clearly not acceptable and measures should be adopted to increase the proportion of prospectively registered trials and to make trial registration an integral part of the research culture.

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BACKGROUND: Fireworks are the leading cause of injuries such as burns and amputations during the Persian Wednesday Eve Festival (Chaharshanbeh Soori). OBJECTIVES: This study was designed to explore the age of the high-risk population, the type of fireworks most frequently causing injury, the pattern of injury, and the frequency of permanent disabilities. METHODS: This cohort study was performed by Tehran Emergency Medical Services at different medical centers all around Tehran, Iran, in individuals referred due to firework-related injuries during 1 month surrounding the festival in the year 2007. The following information was extracted from the patients' medical records: demographic data, the type of fireworks causing injury, the pattern and severity of the injury, the pre-hospital and hospital care provided for the patient, and the patient's condition at the time of discharge. In addition, information on the severity of the remaining disability was recorded 8 months after the injury. RESULTS: There were 197 patients enrolled in the study with a mean age of 20.94 ± 11.31 years; the majority of them were male. Fuse-detonated noisemakers and homemade grenades were the most frequent causes of injury. Hand injury was reported in 39.8% of the cases. Amputation and long-term disability were found in 6 and 12 cases, respectively. None of the patients died during the study period. CONCLUSION: The fireworks used during a Chaharshanbe Soori ceremony were responsible for a considerable number of injuries to different parts of the body, and some of them led to permanent disabilities.

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OBJECTIVES: Pre-hospital care plays a vital role in the management of trauma patients. The present study was designed to evaluate the efficacy of the pre-hospital care performed by the Tehran Emergency Medical Service (EMS) in trauma patients. METHODS: The prospective study was performed on trauma patients referred to the emergency department of a teaching hospital by the Tehran EMS from September 2004 until 2005. Considering the lack of scientific observation-based protocols on pre-hospital care, certain protocols were developed based on the available up-to-date protocols in the emergency medicine text books and were used as the gold standard for comparing the provided care by EMSs. RESULTS: The effectiveness of pre-hospital care performed by Tehran emergency technicians, compatible with the patients' condition, was evaluated in 994 patients. Wound bandaging and haemostasis were done correctly in 80% of the indicated cases. Splint was applied correctly in 50% of patients in need for such a device, whereas collar and spinal bed were not performed in 80% of the indicated cases. CONCLUSIONS: Tehran's EMS is not capable of providing trauma patients with effective and accurate pre-hospital care, indicating that major changes are needed to improve this.

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A simple mono-enzyme biosensor has been developed for specific determination of paraoxon (POX). In this biosensor, choline oxidase (ChOx) was introduced and used as a new recognition element. Besides, by application of Prussian blue (PB), as an electron mediator, the necessity of applying oxygen or hydrogen peroxide sensor, as the internal transducer, was abated. The method was based on PB chemically modified screen-printed electrode coupled with ChOx for detection of POX as inhibitor. The concentration of H(2)O(2) produced by ChOx was electrochemically determined by the PB modified electrode at -50 mV versus the internal screen-printed Ag pseudo-reference electrode. The decrease in current caused by the addition of inhibitor was used for evaluation of POX concentration. The experimental parameters such as the quantity of enzyme, substrate concentration and incubation time were optimized for ChOx inhibition. At the incubation time of 5 min, the biosensor response was linear from 0.1 to 1 microM of POX with a detection limit of 0.1 microM.

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BACKGROUND: Laparoscopic techniques for placement of peritoneal dialysis catheters are becoming increasingly popular. In this paper, we report the results of one-port laparoscopic placement of Tenckhoff catheters in 79 patients in our center. METHOD: Videoscopic monitoring was performed via a port inserted in the left upper quadrant and the catheter was placed via a pull-apart sheath through an incision near the umbilicus. The tip and the deep cuff of the catheter were placed into the true pelvis (on the urinary bladder) and into the rectus sheath respectively. A subcutaneous tunnel was created and a point midway on the umbilico-crestal line was selected as the exit site of the catheter. Catheters were capped for 2 weeks before initiation of peritoneal dialysis. Mean duration of the operation was 25 minutes. RESULTS: Four patients died during the follow-up period, all due to other medical problems, and 4 patients underwent renal transplantation. During a 48-month follow-up, catheter-related complications were catheter migration (1.3%; month 1), dialysate leakage (1.3%; month 1), portsite hernia (3.8%; after 6 months), exit-site infection (2.5%; months 1 and 9), and bacterial peritonitis (2.5%; after 6 months). Catheter survival was 97.2% in our series. CONCLUSION: We obtained a low complication rate and a high catheter survival rate with this one-port laparoscopic technique.

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BACKGROUND: Gastroesophageal reflux, by exposing the pharynx to Helicobacter pylori (H. pylori), is a potential risk factor for laryngo-hypopharyngeal carcinoma. Its possible association has been inconsistent. In this case-control study, we investigated the relationship between H. pylori seropositivity and laryngo-hypopharyngeal carcinoma in Iran. METHODS: We had 105 healthy controls (group A), 70 cases of laryngeal carcinoma (group B), and 28 cases of hypopharyngeal carcinoma group (group C). Age, sex, smoking habit, alcohol use, and H. pylori serology were determined for all subjects. RESULTS: Groups were matched in age and alcohol use. Smoking and H. pylori seropositivity were more common in groups B and C, and male sex was more common in group B (compared with group A). In multivariate regression, the effect of smoking (p <.01, odds ratio [OR] = 2.92) and H. pylori seropositivity (p <.01, OR = 11.49) remained highly significant. CONCLUSION: H. pylori is an independent risk factor for laryngo-hypopharyngeal carcinoma.

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