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The expression dysregulation of microRNAs (miRNA) has been widely reported during cancer development, however, the underling mechanism remains largely unanswered. In the present work, we performed a systematic integrative study for genome-wide DNA methylation, copy number variation and miRNA expression data to identify mechanisms underlying miRNA dysregulation in lower grade glioma. We identify 719 miRNAs whose expression was associated with alterations of copy number variation or promoter methylation. Integrative multi-omics analysis revealed four subtypes with differing prognoses. These glioma subtypes exhibited distinct immune-related characteristics as well as clinical and genetic features. By construction of a miRNA regulatory network, we identified candidate miRNAs associated with immune evasion and response to immunotherapy. Finally, eight prognosis related miRNAs were validated to promote cell migration, invasion and proliferation through in vitro experiments. Our study reveals the crosstalk among DNA methylation, copy number variation and miRNA expression for immune regulation in glioma, and could have important implications for patient stratification and development of biomarkers for immunotherapy approaches. A miRNA multi-omics study reveals not only mechanisms for miRNA dysregulation, but also the tumor heterogeneity and immunological diversity within low grade glioma, and presents better prognostic value than traditional molecular markers. [ABSTRACT FROM AUTHOR]

Objectives: To establish a deep learning (DL) model for predicting tumor grades and expression of pathologic markers of meningioma. Methods: A total of 1192 meningioma patients from two centers who underwent surgical resection between September 2018 and December 2021 were retrospectively included. The pathological data and post-contrast T1-weight images for each patient were collected. The patients from institute I were subdivided into training, validation, and testing sets, while the patients from institute II served as the external testing cohort. The fine-tuned ResNet50 model based on transfer learning was adopted to classify WHO grade in the whole cohort and predict Ki-67 index, H3K27me3, and progesterone receptor (PR) status of grade 1 meningiomas. The predictive performance was evaluated by the accuracy and loss curve, confusion matrix, receiver operating characteristic curve (ROC), and area under curve (AUC). Results: The DL prediction model for each label achieved high predictive performance in two cohorts. For WHO grade prediction, the area under the curve (AUC) was 0.966 (95%CI 0.957–0.975) in the internal testing set and 0.669 (95%CI 0.643–0.695) in the external validation cohort. The AUC in predicting Ki-67 index, H3K27me3, and PR status were 0.905 (95%CI 0.895–0.915), 0.773 (95%CI 0.760–0.786), and 0.771 (95%CI 0.750–0.792) in the internal testing set and 0.591 (95%CI 0.562–0.620), 0.658 (95%CI 0.648–0.668), and 0.703 (95%CI 0.674–0.732) in the external validation cohort, respectively. Conclusion: DL models can preoperatively predict meningioma grades and pathologic marker expression with favorable predictive performance. Clinical relevance statement: Our DL model could predict meningioma grades and expression of pathologic markers and identify high-risk patients with WHO grade 1 meningioma, which would suggest a more aggressive operative intervention preoperatively and a more frequent follow-up schedule postoperatively. Key Points: WHO grades and some pathologic markers of meningioma were associated with therapeutic strategies and clinical outcomes. A deep learning–based approach was employed to develop a model for predicting meningioma grades and the expression of pathologic markers. Preoperative prediction of meningioma grades and the expression of pathologic markers was beneficial for clinical decision-making. [ABSTRACT FROM AUTHOR]

Long noncoding RNAs (lncRNAs) play crucial roles in tumor progression and are dysregulated in glioma. However, the functional roles of lncRNAs in glioma remain largely unknown. In this study, we utilized the TCGA (the Cancer Genome Atlas database) and GEPIA2 (Gene Expression Profiling Interactive Analysis 2) databases and observed the overexpression of lncRNA CHASERR in glioma tissues. We subsequently investigated this phenomenon in glioma cell lines. The effects of lncRNA CHASERR on glioma proliferation, migration, and invasion were analyzed using in vitro and in vivo experiments. Additionally, the regulatory mechanisms among PTEN/p-Akt/mTOR and Wnt/β-catenin, lncRNA CHASERR, Micro-RNA-6893-3p(miR-6893-3p), and tripartite motif containing14 (TRIM14) were investigated via bioinformatics analyses, quantitative real-time PCR (qRT-PCR), western blot (WB), RNA immunoprecipitation (RIP), dual luciferase reporter assay, fluorescence in situ hybridization (FISH), and RNA sequencing assays. RIP and RT-qRCR were used to analyze the regulatory effect of N6-methyladenosine(m6A) on the aberrantly expressed lncRNA CHASERR. High lncRNA CHASERR expression was observed in glioma tissues and was associated with unfavorable prognosis in glioma patients. Further functional assays showed that lncRNA CHASERR regulates glioma growth and metastasis in vitro and in vivo. Mechanistically, lncRNA CHASERR sponged miR-6893-3p to upregulate TRIM14 expression, thereby facilitating glioma progression. Additionally, the activation of PTEN/p-Akt/mTOR and Wnt/β-catenin pathways by lncRNA CHASERR, miR-6893-3p, and TRIM14 was found to regulate glioma progression. Moreover, the upregulation of lncRNA CHASERR was observed in response to N6-methyladenosine modification, which was facilitated by METTL3/YTHDF1-mediated RNA transcripts. This study elucidates the m6A/lncRNACHASERR/miR-6893-3p/TRIM14 pathway that contributes to glioma progression and underscores the potential of lncRNA CHASERR as a novel prognostic indicator and therapeutic target for glioma. [ABSTRACT FROM AUTHOR]

Primary angle closure disease (PACD) is a major cause of blindness worldwide. It has a high prevalence in East Asia, especially in China, which leads to a higher incidence of blindness than open-angle glaucoma. The aim of this study was to directly observe the circumlental space (CLS) in laser peripheral iridotomized eyes with PACD and to determine whether this structure plays a role in the pathogenesis of PACD. Fifty eyes of 50 patients with PACD, who had received laser peripheral iridotomy performed with neodymium:yttrium–aluminum-garnet were recruited from glaucoma clinics from March 2021 to May 2022, including 17 primary angle closure suspect (PACS), 16 primary angle closure (PAC) and 17 primary angle closure glaucoma (PACG). They were classified into two groups based on whether the ciliary process and the crystalline lens equator were in contact using slit-lamp photograph: the attached group and the unattached group. The demographic, clinical characteristics and anterior segment parameters measured from ultrasound biomicroscopy were compared between the attached group and the unattached group. Thirty-three eyes were assigned to the attached group and 17 eyes belonged to the unattached group. In the unattached group, the mean CLS was 0.10 ± 0.07 mm. No significant differences were identified between the different diagnosis groups in age, sex, best-corrected visual acuity, intraocular pressure, white-to-white, axial length, central corneal thickness, anterior chamber depth, flat keratometry, steep keratometry or iridotomy diameter (p > 0.05). The unattached group had shorter trabecular-ciliary process distance (p = 0.021) and larger ciliary process area (p = 0.001) compared with the attached group. Small CLS and its potential effect (partial ciliary block) might be considered as one of the mechanisms of PACD. [ABSTRACT FROM AUTHOR]

Objectives: The first treatment strategy for brain metastases (BM) plays a pivotal role in the prognosis of patients. Among all strategies, stereotactic radiosurgery (SRS) is considered a promising therapy method. Therefore, we developed and validated a radiomics-based prediction pipeline to prospectively identify BM patients who are insensitive to SRS therapy, especially those who are at potential risk of progressive disease. Methods: A total of 337 BM patients (277, 30, and 30 in the training set, internal validation set, and external validation set, respectively) were enrolled in the study. 19,377 radiomics features (3 masks × 3 MRI sequences × 2153 features) extracted from 9 ROIs were filtered through LASSO and Max-Relevance and Min-Redundancy (mRMR) algorithms. The selected radiomics features were combined with 4 clinical features to construct a two-stage cascaded model for the prediction of BM patients' response to SRS therapy using SVM and an ensemble learning classifier. The performance of the model was evaluated by its accuracy, specificity, sensitivity, and AUC curve. Results: Radiomics features were integrated with the clinical features of patients in our optimal model, which showed excellent discriminative performance in the training set (AUC: 0.95, 95% CI: 0.88–0.98). The model was also verified in the internal validation set and external validation set (AUC 0.93, 95% CI: 0.76–0.95 and AUC 0.90, 95% CI: 0.73–0.93, respectively). Conclusions: The proposed prediction pipeline could non-invasively predict the response to SRS therapy in patients with brain metastases thus assisting doctors to precisely designate individualized first treatment decisions. Clinical relevance statement: The proposed prediction pipeline combines the radiomics features of multi-modal MRI with clinical features to construct machine learning models that noninvasively predict the response of patients with brain metastases to stereotactic radiosurgery therapy, assisting neuro-oncologists to develop personalized first treatment plans. Key Points: • The proposed prediction pipeline can non-invasively predict the response to SRS therapy. • The combination of multi-modality and multi-mask contributes significantly to the prediction. • The edema index also shows a certain predictive value. [ABSTRACT FROM AUTHOR]

Purpose: Neuroplasticity can partially compensate for the neurological deficits caused by brain tumors. However, the structural plasticity of the brain caused by brain tumors is not fully understood. This study aimed to assess the structural plasticity of the contralesional hemisphere in patients with frontal low-grade gliomas (LGGs). Methods: A total of 25 patients with left frontal LGGs (LFLGGs), 19 patients with right frontal LGGs (RFLGGs), and 25 healthy controls (HCs) were enrolled in this study. High-resolution structural T1-weighted imaging and fluid attenuation inversion recovery were performed on all participants. Voxel-based morphometry (VBM) analysis was used to detect differences in the brain structural plasticity between patients with unilateral LGGs and HCs. Results: VBM analysis revealed that compared with HCs, the gray matter volume (GMV) of the contralesional putamen and amygdala was significantly smaller and larger in the patients with RFLGGs and LFLGGs, respectively, while the GMVs of the contralesional cuneus and superior temporal gyrus (STG) were significantly larger in the patients with LFLGGs. The surviving clusters of the right hemisphere included 1357 voxels in the amygdala, 1680 voxels in the cuneus, 384 voxels in the STG, and 410 voxels in the putamen. The surviving clusters of the left hemisphere were 522 voxels in the amygdala and 320 voxels in the putamen. Conclusion: The unilateral frontal LGGs are accompanied by structural plasticity in the contralesional cortex and vary with tumor laterality. Contralesional structural reorganization may be one of the physiological basis for functional reorganization or compensation in the frontal LGGs. [ABSTRACT FROM AUTHOR]

This study aimed to explore and impart understanding of bone remodelling in children with intracapsular fractures treated conservatively. Records of children (less than 12 years), who sustained intracapsular fractures and treated conservatively, were retrieved consecutively for the period of March 2011 to February 2016. Data about age, gender, date of injury, dates of admission and discharge, mechanism of trauma, location and pattern of fracture, other mandibular fractures, treatment methods and time of review were recorded and analysed. Image dates of pre- and post-treatments, including date of review, were also recorded. A total of 22 patients complete their follow-up and show bone remodelling process. During their follow-up, all the displaced condylar fragments fused with the ramus stump at the displaced position. Regardless of the type of conservative procedure, both treatments cannot promote the spontaneous fracture reduction in patients with intracapsular condylar fractures. During follow-up, the absorption of the lateral process of the condyle after the closed treatment becomes close to the 'horizontal absorption', until the height (or articular surface) of the lateral condylar process dropped and aligned to the articular surface of the medial process. In children with intracapsular condylar fractures, the fracture fragment of the condyle determines the ramus height of the mandible. Closed treatment cannot restore the fracture fragment. If the height of the fracture fragments dropped remarkably, then open reduction and rigid internal fixation become more suitable. [ABSTRACT FROM AUTHOR]

Background: Recently, there has been a burgeoning interest in radiofrequency ablation combined with stent (RFA + Stent) for unresectable malignant biliary obstruction (MBO). This study aimed to perform a meta-analysis to evaluate the efficacy and safety of RFA + Stent compared with biliary stent alone. Methods: We searched PubMed, Cochrane Library, Embase, and Web of Science databases from their inception dates to June 20, 2021, for studies that compared RFA + Stent and stent alone for unresectable MBO. The main outcomes were survival, patency, and adverse effects. All meta-analyses were calculated using the random-effects model. Results: A total of 19 studies involving 1946 patients were included in this study. Compared with stent alone, RFA + Stent was significantly associated with better overall survival (HR 0.55; 95% CI 0.48, 0.63; P < 0.00001), longer mean survival time (SMD 2.20; 95% CI 1.17, 3.22; P < 0.0001), longer mean stent patency time (SMD 1.37; 95% CI 0.47, 2.26; P = 0.003), higher stent patency at 6 months (OR 2.82; 95% CI 1.54, 5.18; P = 0.0008). The two interventions had similar incidence of postoperative abdominal pain (OR 1.29; 95% CI 0.94, 1.78; P = 0.11), mild bleeding (OR 1.28; 95% CI 0.65, 2.54; P = 0.48), cholangitis (OR 1.09; 95% CI 0.76, 1.55; P = 0.65), pancreatitis (OR 1.39; 95% CI 0.82, 2.38; P = 0.22). Furthermore, the serum bilirubin levels and stricture diameter after operations were significantly alleviated than before operations, but the degree of alleviation between the two groups were not significantly different (all P > 0.05). Conclusion: Although the alleviation of serum bilirubin and stricture diameter did not differ between the two interventions, RFA + Stent can significantly improve the survival and stent patency with comparable procedure-related adverse events than stent alone. Thus, RFA + Stent should be recommended as an attractive alternative to biliary stent alone for patients with unresectable MBO. [ABSTRACT FROM AUTHOR]

Aiming at the deformation and failure of roadway surrounding rock and its control problems under goaf in upper and lower coal seam mining of Buertai Coal Mine, the distribution characteristics of surrounding rock stress in different mining stages of goaf were analyzed, the evolution law of plastic zone of roadway surrounding rock under goaf was analyzed, and the failure mechanism of roadway surrounding rock was revealed by theoretical calculation and numerical simulation.The results show that: the principal stress of the mining roadway under the goaf is smaller than that of the original rock stress. The plastic zone of surrounding rock is small during excavation. Affected by the first mining, the maximum principal stress is 1.24 times of the original rock stress, and the minimum principal stress is 1.49 times of the original rock stress. Affected by the secondary mining, the maximum principal stress is 1.52 times of the original rock stress, and the minimum principal stress is 1.74 times of the original rock stress. In order to control the malignant development of surrounding rock plastic zone, the staged support technology in different mining stages is proposed, and the stress environment of surrounding rock is improved by hydraulic fracturing, so as to reduce the plastic zone of surrounding rock and maintain the safety and stability of surrounding rock. [ABSTRACT FROM AUTHOR]

Purpose: Gliomas are the most common primary brain tumor. Currently, topological alterations of whole-brain functional network caused by gliomas are not fully understood. The work here clarified the topological reorganization of the functional network in patients with unilateral frontal low-grade gliomas (LGGs).A total of 45 patients with left frontal LGGs, 19 with right frontal LGGs, and 25 healthy controls (HCs) were enrolled. All the resting-state functional MRI (rs-fMRI) images of the subjects were preprocessed to construct the functional network matrix, which was used for graph theoretical analysis. A two-sample t-test was conducted to clarify the differences in global and nodal network metrics between patients and HCs. A network-based statistic approach was used to identify the altered specific pairs of regions in which functional connectivity in patients with LGGs.The local efficiency, clustering coefficient, characteristic path length, and normalized characteristic path length of patients with unilateral frontal LGGs were significantly lower than HCs, while there were no significant differences of global efficiency and small-worldness between patients and HCs. Compared with the HCs, betweenness centrality, degree centrality, and nodal efficiency of several brain nodes were changed significantly in patients. Around the tumor and its adjacent areas, the inter- and intra-hemispheric connections were significantly decreased in patients with left frontal LGGs.The patients with unilateral frontal LGGs have altered global and nodal network metrics and decreased inter- and intra-hemispheric connectivity. These topological alterations may be involved in functional impairment and compensation of patients.Methods: Gliomas are the most common primary brain tumor. Currently, topological alterations of whole-brain functional network caused by gliomas are not fully understood. The work here clarified the topological reorganization of the functional network in patients with unilateral frontal low-grade gliomas (LGGs).A total of 45 patients with left frontal LGGs, 19 with right frontal LGGs, and 25 healthy controls (HCs) were enrolled. All the resting-state functional MRI (rs-fMRI) images of the subjects were preprocessed to construct the functional network matrix, which was used for graph theoretical analysis. A two-sample t-test was conducted to clarify the differences in global and nodal network metrics between patients and HCs. A network-based statistic approach was used to identify the altered specific pairs of regions in which functional connectivity in patients with LGGs.The local efficiency, clustering coefficient, characteristic path length, and normalized characteristic path length of patients with unilateral frontal LGGs were significantly lower than HCs, while there were no significant differences of global efficiency and small-worldness between patients and HCs. Compared with the HCs, betweenness centrality, degree centrality, and nodal efficiency of several brain nodes were changed significantly in patients. Around the tumor and its adjacent areas, the inter- and intra-hemispheric connections were significantly decreased in patients with left frontal LGGs.The patients with unilateral frontal LGGs have altered global and nodal network metrics and decreased inter- and intra-hemispheric connectivity. These topological alterations may be involved in functional impairment and compensation of patients.Results: Gliomas are the most common primary brain tumor. Currently, topological alterations of whole-brain functional network caused by gliomas are not fully understood. The work here clarified the topological reorganization of the functional network in patients with unilateral frontal low-grade gliomas (LGGs).A total of 45 patients with left frontal LGGs, 19 with right frontal LGGs, and 25 healthy controls (HCs) were enrolled. All the resting-state functional MRI (rs-fMRI) images of the subjects were preprocessed to construct the functional network matrix, which was used for graph theoretical analysis. A two-sample t-test was conducted to clarify the differences in global and nodal network metrics between patients and HCs. A network-based statistic approach was used to identify the altered specific pairs of regions in which functional connectivity in patients with LGGs.The local efficiency, clustering coefficient, characteristic path length, and normalized characteristic path length of patients with unilateral frontal LGGs were significantly lower than HCs, while there were no significant differences of global efficiency and small-worldness between patients and HCs. Compared with the HCs, betweenness centrality, degree centrality, and nodal efficiency of several brain nodes were changed significantly in patients. Around the tumor and its adjacent areas, the inter- and intra-hemispheric connections were significantly decreased in patients with left frontal LGGs.The patients with unilateral frontal LGGs have altered global and nodal network metrics and decreased inter- and intra-hemispheric connectivity. These topological alterations may be involved in functional impairment and compensation of patients.Conclusion: Gliomas are the most common primary brain tumor. Currently, topological alterations of whole-brain functional network caused by gliomas are not fully understood. The work here clarified the topological reorganization of the functional network in patients with unilateral frontal low-grade gliomas (LGGs).A total of 45 patients with left frontal LGGs, 19 with right frontal LGGs, and 25 healthy controls (HCs) were enrolled. All the resting-state functional MRI (rs-fMRI) images of the subjects were preprocessed to construct the functional network matrix, which was used for graph theoretical analysis. A two-sample t-test was conducted to clarify the differences in global and nodal network metrics between patients and HCs. A network-based statistic approach was used to identify the altered specific pairs of regions in which functional connectivity in patients with LGGs.The local efficiency, clustering coefficient, characteristic path length, and normalized characteristic path length of patients with unilateral frontal LGGs were significantly lower than HCs, while there were no significant differences of global efficiency and small-worldness between patients and HCs. Compared with the HCs, betweenness centrality, degree centrality, and nodal efficiency of several brain nodes were changed significantly in patients. Around the tumor and its adjacent areas, the inter- and intra-hemispheric connections were significantly decreased in patients with left frontal LGGs.The patients with unilateral frontal LGGs have altered global and nodal network metrics and decreased inter- and intra-hemispheric connectivity. These topological alterations may be involved in functional impairment and compensation of patients. [ABSTRACT FROM AUTHOR]

Ezrin is overexpressed in a variety of neoplastic cells and involved in the later stages of tumor progression and metastasis. Ezrin expression can be regulated at both the transcriptional and post-transcriptional levels. We used a combination of bioinformatics and experimental techniques to demonstrate that the miR-204 is a direct negative regulator of ezrin. Overexpression of miR-204 mimics decreased the activity of a luciferase reporter containing the ezrin 3′ UTR and led to repression of ezrin protein. In contrast, ectopic expression of miR-204 inhibitor elevated ezrin expression. We also show that miR-204 is down-regulated in a panel of glioma tissues and in high invasive glioma cell lines we examined. Moreover, miR-204 mimics significantly reduced glioma cell migration and invasion, while miR-204 inhibitor generated the opposite results. Finally, overexpression of miR-204 and knockdown of ezrin reduced glioma cell invasion, and these effects could be rescued by re-expression of ezrin. These findings reveal that miR-204 could be partly due to its inhibitory effects on glioma cell migration and invasion through regulating ezrin expression. [ABSTRACT FROM AUTHOR]

In this study we explored the effects of microRNA let-7a on Con A-induced hepatitis and its possible mechanisms involved. We demonstrated that IL-6 and IL-17 expression were significantly upregulated in the liver following Con A treatment and IL-6 level was correlated with the IL-17 expression. To explore whether let-7a may have therapeutic effect on Con A-induced hepatitis, mice was infected with a lentiviral vector containing the let-7a sequence 7 days before Con A treatment. Significantly reduced Th17 cells and remarkably increased regulatory T cells frequency in the liver tissue were found as compared to control mice. It was accompanied by a significant decreased level of inflammatory cytokines as TNF-α, IL-6 and IFN-γ in the serum, and an decreased level of Th17 lineage-specific genes such as Il17a, Il17f, Il21 and Il23r. let-7a was further found to inhibit Th17 differentiation by downregulating IL-6 secretion. It may represent as a novel therapeutic strategy in treating immune-mediated inflammatory hepatitis. [ABSTRACT FROM AUTHOR]

Elymus nutans is an herbaceous plant that can be used to restore degraded alpine and subalpine ecosystems. Here, we evaluated how sowing density affects soil reinforcement and slope stabilization properties of vegetation–concrete structures. To investigate the optimal sowing density of E. nutans in vegetation–concrete applications for slope protection, six experimental treatments were established with different plant densities: control, I (1100 seeds/m2), II (2200 seeds/m2), III (3300 seeds/m2), IV (4400 seeds/m2), and V (5500 seeds/m2). Several parameters of plant growth in addition to soil reinforcement and slope stabilization properties were measured in each treatment, as well as the associations among parameters. As density increased, aboveground biomass continually increased, and plant heights, root surface areas, root lengths, and underground biomass all first increased and then decreased. In contrast, tiller numbers and the average root diameter gradually decreased with increasing density. Increased density also resulted in increased maximum water interception levels by aboveground stems and leaves. The maximum water interception by the aboveground stems and leaves was 41.75% greater in the highest density treatment (V) compared to the lowest density treatment (I). However, the enhancement of erosion resistance and soil shear strength first increased and then decreased as density increased, with maximal values observed in the medium-high density treatment (IV). Sowing density was highly correlated with aboveground biomass, plant heights, tiller numbers, and the maximum level of water interception by stems and leaves. Thus, sowing density directly influenced soil reinforcement and slope stabilization properties of aboveground plant components. However, density was not significantly correlated with belowground biomass, root lengths, root surface areas, the enhancement of erosion resistance, and soil shear strengths. Therefore, sowing density indirectly influenced soil reinforcement and slope stabilization of belowground plant components. Following from these results, we suggest that the optimal sowing density of E. nutans is approximately 4400 plants/m2 in their application within vegetation–concrete structures used for slope protection. [ABSTRACT FROM AUTHOR]

An ultrathin and flexible metamaterial absorber (MA) with triple absorption peaks is presented in this paper. The proposed absorber has been designed in such a way that three absorption peaks are located at 8.5, 13.5, and 17 GHz (X and Ku bands) with absorption of 99.9%, 99.5%, and 99.9%, respectively. The proposed structure is only 0.4 mm thick, which is approximately 1/88, 1/55, and 1/44 for the respective free space wavelengths of absorption frequency in various bands. The MA is also insensitive due to its symmetric geometry. In addition, the proposed structure exhibits minimum 86% absorption (TE incidence) within 60° angle of incidence. For TM incidence, the proposed absorber exhibits more than 99% absorptivity up to 60° incidence. Surface current and electric field distributions were investigated to analyze the mechanism governing absorption. Parameter analyses were performed for absorption optimization. Moreover, the performance of the MA was experimentally demonstrated in free space on a sample under test with 20 × 30 unit cells fabricated on a flexible dielectric. Under normal incidence, the fabricated MA exhibits near perfect absorption at each absorption peak for all polarization angles, and the experimental results were found to be consistent with simulation results. Due to its advantages of high-efficiency absorption over a broad range of incidence angles, the proposed absorber can be used in energy harvesting and electromagnetic shielding. [ABSTRACT FROM AUTHOR]