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Artificially molding exciton flux is the cornerstone for developing promising excitonic devices. In the emerging hetero/homobilayers, the spatial separated charges prolong exciton lifetimes and create out-plane dipoles, facilitating electrically control exciton flux on a large scale, and the nanoscale periodic moiré potentials arising from twist-angle or/and lattice mismatch can substantially alter exciton dynamics, which are mainly proved in the heterostructures. However, the spatially indirect excitons dynamics in homobilayers without lattice mismatch remain elusive. Here the nonequilibrium dynamics of indirect exciton in homobilayers are systematically investigated. The homobilayers with slightly twist-angle can induce a deep moiré potential (>50 meV) in the energy landscape of indirect excitons, resulting in a strongly localized moiré excitons insulating the transport dynamics from phonons and disorder. These findings provide insights into the exciton dynamics and many-body physics in moiré superlattices modulated energy landscape, with implications for designing excitonic devices operating at room temperature.
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BACKGROUND: Experimental studies have shown that disinfection byproducts (DBPs) induce coagulotoxicity, but human evidence is scarce. OBJECTIVE: This study aimed to explore the relationships of DBP exposures with blood coagulation parameters. METHODS: Among 858 women from the Tongji Reproductive and Environmental (TREE) study, urinary dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) were detected as internal biomarkers of DBP exposures. We measured activated partial thromboplastin time (APTT), fibrinogen (Fbg), international normalized ratio (INR), prothrombin time (PT), and thrombin time (TT) as blood coagulation parameters. Multivariable linear regression models were utilized to estimate the relationships between urinary DCAA and TCAA and blood coagulation parameters. The effect modifications by demographic and lifestyle characteristics were further explored. RESULTS: Elevated tertiles of urinary DCAA concentrations were associated with increased PT and INR (11.29%, 95% CI: 1.66%, 20.92% and 0.99%, 95% CI: 0.08%, 1.90% for the third vs. first tertile, respectively; both P for trends < 0.05). Stratification analysis showed that the positive associations were only observed among younger (< 30 years), leaner (body mass index < 24.0 kg/m2), and non-passive smoking women. Moreover, elevated tertiles of urinary TCAA concentrations in positive associations with PT and INR were observed among younger women (17.89%, 95% CI: 2.50%, 33.29% and 1.82%, 95% CI: 0.34%, 3.30% for the third vs. first tertile, respectively; both P for trends < 0.05) but not among older women (both P for interactions < 0.05). CONCLUSION: Higher levels of urinary DCAA and TCAA are associated with prolonged clotting time among women.
Subject(s)
Disinfection , Reproduction , Humans , Female , Aged , Disinfection/methods , Blood Coagulation , Trichloroacetic Acid/urine , Biomarkers/urine , Dichloroacetic Acid/urineABSTRACT
Additional neural substance for reading in a second language has been reported by prior studies. However, to date, there has been little investigation into whether and how the brain's adaptation to a second language is induced by specific linguistic tasks or is a general effect during reading in a new language. To address this issue, our study investigated Chinese children learning English as a second language by combining cross-sectional and longitudinal Functional Magnetic Resonance Imaging (fMRI) studies. We compared brain activation across four reading tasks, orthographic tasks and phonological tasks in Chinese (the first language, L1) and English (the second language, L2). By comparing the activation pattern across languages, we observed greater activation in the left inferior parietal lobule (LIPL) in English compared to Chinese, suggesting a functional preference of the LIPL to L2. In addition, greater correlation between LIPL-related FC and L2 was mainly observed in the phonological task, indicating that LIPL could be associated with phonological processing. Moreover, a proportion of the children were enrolled in an 8-week phonological-based reading-training program. We observed significant functional plasticity of the LIPL elicited by this training program only in the English phonological task and not in the orthographic task, further substantiating that the additional requirements of the LIPL in L2 are mainly associated with phonological processing. The findings provide new insights into understanding the functional contribution of the LIPL to reading in a second language.
Subject(s)
Multilingualism , Reading , Child , Humans , Brain Mapping , Cross-Sectional Studies , Brain/physiology , Language , Parietal Lobe/diagnostic imaging , Magnetic Resonance ImagingABSTRACT
The process of complex cognition, which includes language processing, is dynamic in nature and involves various network modes or cognitive modes. This dynamic process can be manifested by a set of brain states and transitions between them. Previous neuroimaging studies have shed light on how bilingual brains support native language (L1) and second language (L2) through a shared network. However, the mechanism through which this shared brain network enables L1 and L2 processing remains unknown. This study examined this issue by testing the hypothesis that L1 and L2 processing is associated with distinct brain state dynamics in terms of brain state integration and transition flexibility. A group of late Chinese-English bilinguals was scanned using functional magnetic resonance imaging (fMRI) while listening to eight short narratives in Chinese (L1) and English (L2). Brain state dynamics were modeled using the leading eigenvector dynamic analysis framework. The results show that L1 processing involves more integrated states and frequent transitions between integrated and segregated states, while L2 processing involves more segregated states and fewer transitions. Our work provides insight into the dynamic process of narrative listening comprehension in late bilinguals and sheds new light on the neural representation of language processing and related disorders.
Subject(s)
Brain , Cognition , Multilingualism , Nerve Net , Humans , Asian People , Brain/diagnostic imaging , Brain/physiology , Cognition/physiology , Language , Narration , Comprehension/physiology , China , Nerve Net/diagnostic imaging , Nerve Net/physiology , Listening Effort/physiologyABSTRACT
Sulfur dioxide (SO2) as one kind of air pollution not only causes extreme environmental pollution but also negatively affects human health. Chemiluminescence (CL) methods applied for sulfite analysis with high selectivity based on activating sulfite with oxidants are always implemented in acid media with a high background rise. In this work, we proposed to develop a mild CL system of Fe2+-SO32- to detect sulfite under neutral conditions and provide in situ CL spectral data for deeply studying the CL mechanism of Fe2+-SO32-. Herein, we first synthesized one type of water-soluble supramolecular nanosheets, APDI NSs, which had a strong oxidation potential (+2.9 V) due to a π-conjugated system for activation of sulfite to enhance the generation of SO3Ì- and other active radicals, and strong a CL signal from the APDI NSs-Fe2+-SO32- system was generated. By studying the CL mechanism under acidic and neutral conditions, a new CL reaction pathway (path-1) and a key intermediate, S2O42-, from the reaction of Fe2+ and SO32- were found. The CL signal was emitted by SO2* after oxidation of S2O42- by strong oxidants like SO4â¢- and further amplified by APDI NSs through the CL resonance energy transfer (CRET) process. Based on the APDI NSs-Fe2+-SO32- system under neutral conditions, a CL method for detecting SO32- was established. The detection limit was 2.7 × 10-8 M (S/N = 3), and the recovery rates in spiked water samples were in the range of 87%-101%. This study strengthens the understanding of the CL reaction process of the Fe2+-SO32- system and provides a mild sulfite sensing platform for environmental samples.
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Contactless integrated photonic probes (CLIPPs) have been used as on-chip power monitors with minimum perturbations to optical modes. In this work, we present the experimental measurements and analysis of the noise properties of these types of devices integrated with silicon waveguides. We focus on the study of how circuitry parameters, including the gain of the trans-impedance amplifier, lock-in bandwidth, and amplitude and frequency of the bias voltage, affect the noise properties. Finally, we establish a circuit model and use the Simulation Program with Integrated Circuit Emphasis to model and simulate the noise properties of these devices. Our analysis shows that the thermal noise of the CLIPPs and electrical noise of the trans-impedance amplifier are the dominant sources of noise.
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In the paper, we employ an improved physics-informed neural network (PINN) algorithm to investigate the data-driven nonlinear wave solutions to the nonlocal Davey-Stewartson (DS) I equation with parity-time (PT) symmetry, including the line breather, kink-shaped and W-shaped line rogue wave solutions. Both the PT symmetry and model are introduced into the loss function to strengthen the physical constraint. In addition, since the nonlocal DS I equation is a high-dimensional coupled system, this leads to an increase in the number of output results. The PT symmetry also needs to be learned that is not given in advance, which increases challenges in computing for multi-output neural networks. To address these problems, our objective is to assign various levels of weight to different items in the loss function. The experimental results show that the improved algorithm has better prediction accuracy to a certain extent compared with the original PINN algorithm. This approach is feasible to investigate complex nonlinear waves in a high-dimensional model with PT symmetry.
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OBJECTIVE: To evaluate the efficacy and safety of apatinib combined with FOLFIRI in the first-line treatment of advanced metastatic colorectal cancer (mCRC) and explore potential factors of efficacy. METHODS: Twenty mCRC patients treated at Affiliated Cancer Hospital of Shanxi Medical University from March 2017 to March 2019 were included according to the enrolment criteria. They provided informed consent and were treated with apatinib combined with FOLFIRI according to the scheduled regimen until disease progression or unacceptable toxicity occurred. The primary endpoint was OS. The secondary endpoints included PFS, ORR, DCRand safety. OS and PFS were calculated using Kaplan-Meier curves. Univariate and multivariate Cox regression analyses were used to evaluate independent prognostic factors of OS and PFS. R was used to determine cut-off values for biochemical indicators. Forest maps were drawn for Cox univariate results and the relationships between NLR and ECOG, which were significant in univariate analysis, and OS were represented by Kaplan-Meier curves. RESULTS: The median OS and PFS were 16.135 months (95% CI: 9.211-22.929) and 6 months (95% CI: 5.425-6.525). Multivariate Cox analysis showed that NLR and CEA were independent prognostic factors. The most common grade 3-4 adverse events were hypertension, diarrhoea, increased alkaline phosphatase, decreased leukocytes and decreased neutrophils. CONCLUSION: Apatinib combined with FOLFIRI for the first-line treatment of advanced unresectable mCRC showed good efficacy and safety. The baseline NLR was predictive of efficacy, and a low baseline NLR (HR: 0.2895, P = 0.0084) was associated with improved OS.Clinical Research Registration Number: ChiCTR1800015308.
Subject(s)
Colonic Neoplasms , Colorectal Neoplasms , Rectal Neoplasms , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Camptothecin/adverse effects , Colonic Neoplasms/drug therapy , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/pathology , Fluorouracil/adverse effects , Humans , Leucovorin/adverse effects , Pyridines/adverse effects , Rectal Neoplasms/drug therapyABSTRACT
We report on a normal-incidence infrared photoconductor based on surface-state absorption in silicon, featuring broad-spectrum photoresponse, sensitivity of ${-}46\;{\rm dBm} $ enabled by lock-in readouts, CMOS-compatible fabrication process, and near transparency to incident light. Its applications in infrared imaging and measuring the beam profiles are demonstrated and presented. Future extension from this single-pixel element to a many-pixel camera is discussed.
Subject(s)
Colorectal Neoplasms , Humans , Colorectal Neoplasms/immunology , Colorectal Neoplasms/blood , Male , Female , Aged , Middle AgedABSTRACT
BACKGROUD: Widespread endothelial injury contributes to the occurrence of preeclampsia. Maspin, first identified as a tumor suppressor, plays a critical role in cell invasion and angiogenesis. Our previous studies found that the expression of maspin was increased in preeclampsic placenta. In this research, we studied the function of human umbilical vein endothelial cells (HUVECs) to explore the role and possible mechanism of maspin gene in the pathogenesis of preeclampsia. METHODS: HUVECs were treated with different concentration of recombinant human maspin protein (r-maspin) during normoxia and hypoxia, we detected the proliferation, apoptosis, migration and tube formation of HUVECs. We also assessed nitride oxide (NO) synthesis and the expression of matrix metalloproteinase 2 (MMP2) to further explore the underlying molecular mechanism. RESULTS: There was only slight maspin expression at mRNA level in HUVECs. Treated HUVECs with r-maspin, the proliferation of HUVECs was significantly promoted both under normoxia and hypoxia. The tubes formed by HUVECs were significantly inhibited and NO synthesis was significantly reduced by r-maspin. Meantime, r-maspin also inhibited MMP2 expression and activity in HUVECs. However, there was no significant change in the migration and apoptosis of HUVECs. CONCLUSIONS: Maspin may be an important participant for mediating endothelial function and ultimately leads to the occurence of preeclamsia.
Subject(s)
Human Umbilical Vein Endothelial Cells/physiology , Pre-Eclampsia/genetics , Serpins/physiology , Apoptosis/genetics , Cell Movement/genetics , Cell Proliferation/genetics , Cells, Cultured , Female , Humans , Hypoxia/metabolism , Matrix Metalloproteinase 2/metabolism , Nitric Oxide/biosynthesis , Placenta/metabolism , PregnancyABSTRACT
A novel and highly efficient heterogeneous palladium-catalyzed carbonylative cross-coupling of aryl iodides with triarylbismuths has been developed that proceeds smoothly at atmospheric CO pressure and provides a general and powerful tool for the preparation of various valuable biaryl ketones with high atom economy, good to excellent yield, and recyclability of the catalyst. The reaction is the first example of Pd-catalyzed carbonylative cross-coupling for the construction of biaryl ketones using triarylbismuths as substrates.
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A kinetics-based method is proposed to quantitatively characterize the collective magnetization of colloidal magnetic nanoparticles. The method is based on the relationship between the magnetic force on a colloidal droplet and the movement of the droplet under a gradient magnetic field. Through computational analysis of the kinetic parameters, such as displacement, velocity, and acceleration, the magnetization of colloidal magnetic nanoparticles can be calculated. In our experiments, the values measured by using our method exhibited a better linear correlation with magnetothermal heating, than those obtained by using a vibrating sample magnetometer and magnetic balance. This finding indicates that this method may be more suitable to evaluate the collective magnetism of colloidal magnetic nanoparticles under low magnetic fields than the commonly used methods. Accurate evaluation of the magnetic properties of colloidal nanoparticles is of great importance for the standardization of magnetic nanomaterials and for their practical application in biomedicine.
Subject(s)
Chemistry Techniques, Analytical/methods , Colloids/chemistry , Magnetite Nanoparticles/chemistry , Chemical Phenomena , Kinetics , MagneticsABSTRACT
Tomato is a popular vegetable worldwide; its production is highly threatened by infection with the potato spindle tuber viroid (PSTVd). We obtained the full-length genome sequence of previously conserved PSTVd and inoculated it on four genotypes of semi-cultivated tomatoes selected from a local tomato germplasm resource. SC-5, which is a PSTVd-resistant genotype, and SC-96, which is a PSTVd-sensitive genotype, were identified by detecting the fruit yield, plant growth, biomass accumulation, physiological indices, and PSTVd genome titer after PSTVd inoculation. A non-target metabolomics study was conducted on PSTVd-infected and control SC-5 to identify potential anti-PSTVd metabolites. The platform of liquid chromatography-mass spectrometry detected 158 or 123 differential regulated metabolites in modes of positive ion or negative ion. Principal component analysis revealed a clear separation of the global metabolite profile between PSTVd-infected leaves and control regardless of the detection mode. The potential anti-PSTVd compounds, xanthohumol, oxalicine B, indole-3-carbinol, and rosmarinic acid were significantly upregulated in positive ion mode, whereas echinocystic acid, chlorogenic acid, and 5-acetylsalicylic acid were upregulated in negative ion mode. Xanthohumol and echinocystic acid were detected as the most upregulated metabolites and were exogenously applied on PSTVd-diseased SC-96 seedlings. Both xanthohumol and echinocystic acid had instant and long-term inhibition effect on PSTVd titer. The highest reduction of disease symptom was induced by 2.6 mg/L of xanthohumol and 2.0 mg/L of echinocystic acid after 10 days of leaf spraying, respectively. A superior effect was seen on echinocystic acid than on xanthohumol. Our study provides a statistical basis for breeding anti-viroid tomato genotypes and creating plant-originating chemical preparations to prevent viroid disease.
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BACKGROUND: Colorectal cancer (CRC) metachronous liver metastasis is a significant clinical challenge, largely attributable to the late detection and the intricate molecular mechanisms that remain poorly understood. This study aims to elucidate the role of Solute Carrier Family 14 Member 1 (SLC14A1) in the pathogenesis and progression of CRC metachronous liver metastasis. METHODS: We conducted a comprehensive analysis of CRC patient data from The Cancer Genome Atlas and GSE40967 databases, focusing on the differential expression of genes associated with non-metachronous liver metastasis and metachronous liver metastasis. Functional assays, both in vitro and in vivo, were performed to assess the biological impact of SLC14A1 modulation in CRC cells. Gene set enrichment analysis, molecular assays and immunohistochemical analyses on clinical specimens were employed to unravel the underlying mechanisms through which SLC14A1 exerts its effects. RESULTS: SLC14A1 was identified as a differentially expressed gene, with its overexpression significantly correlating with poor relapse-free and overall survival. Mechanistically, elevated SLC14A1 levels enhanced CRC cell invasiveness and migratory abilities, corroborated by upregulated TGF-ß/Smad signaling and Epithelial-Mesenchymal Transition. SLC14A1 interacted with TßRII and stabilized TßRII protein, impeding its Smurf1-mediated K48-linked ubiquitination and degradation, amplifying TGF-ß/Smad signaling. Furthermore, TGF-ß1 reciprocally elevated SLC14A1 mRNA expression, with Snail identified as a transcriptional regulator, binding downstream of SLC14A1's transcription start site, establishing a positive feedback loop. Clinically, SLC14A1, phosphorylated Smad2, and Snail were markedly upregulated in CRC patients with metachronous liver metastasis, underscoring their potential as prognostic markers. CONCLUSIONS: Our findings unveil SLC14A1 as a critical regulator in CRC metachronous liver metastasis, providing novel insights into the molecular crosstalk between SLC14A1 and TGF-ß/Smad signaling. These discoveries not only enhance our understanding of CRC metachronous liver metastasis pathogenesis, but also highlight SLC14A1 as a promising target for therapeutic intervention and predictive marker.
Subject(s)
Colorectal Neoplasms , Epithelial-Mesenchymal Transition , Liver Neoplasms , Signal Transduction , Transforming Growth Factor beta , Animals , Female , Humans , Male , Mice , Cell Line, Tumor , Colorectal Neoplasms/pathology , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/genetics , Gene Expression Regulation, Neoplastic , Liver Neoplasms/secondary , Liver Neoplasms/metabolism , Liver Neoplasms/genetics , Liver Neoplasms/pathology , Prognosis , Transforming Growth Factor beta/metabolismABSTRACT
BACKGROUND: Although adjuvant chemotherapy (ACT) is widely used to treat patients with Stage II/III colorectal cancer (CRC), administering ACT to specific patients remains a challenge. The decision to ACT requires an accurate assessment of recurrence risk and absolute treatment benefit. However, the traditional TNM staging system does not accurately assess a patient's individual risk of recurrence. METHODS: To identify recurrence risk-related genetic factors for Stage II/III CRC patients after radical surgery, we conducted an analysis of whole-exome sequencing of 47 patients with Stage II/III CRC who underwent radical surgery at five institutions. Patients were grouped into non-recurrence group (NR, n = 24, recurrence-free survival [RFS] > 5 years) and recurrence group (R, n = 23, RFS <2 years). The TCGA-COAD/READ cohort was employed as the validation dataset. RESULTS: A recurrence-predictive model (G8plus score) based on eight gene (CUL9, PCDHA12, HECTD3, DCX, SMARCA2, FAM193A, AATK, and SORCS2) mutations and tumor mutation burden/microsatellite instability (TMB/MSI) status was constructed, with 97.87% accuracy in our data and 100% negative predictive value in the TCGA-COAD/READ cohort. For the TCGA-COAD/READ cohort, the G8plus-high group had better RFS (HR = 0.22, p = 0.024); the G8plus-high tumors had significantly more infiltrated immune cell types, higher tertiary lymphoid structure signature scores, and higher immunological signature scores. The G8plus score was also a predict biomarker for immunotherapeutic in advanced CRC in the PUCH cohort. CONCLUSIONS: In conclusion, the G8plus score is a powerful biomarker for predicting the risk of recurrence in patients with stage II/III CRC. It can be used to stratify patients who benefit from ACT and immunotherapy.
Subject(s)
Colorectal Neoplasms , Microsatellite Instability , Humans , Prognosis , Colorectal Neoplasms/therapy , Colorectal Neoplasms/drug therapy , Neoplasm Staging , Biomarkers, Tumor/geneticsABSTRACT
Utilizing statistical information from the Seventh National Population Census, statistical yearbook and sampling dynamic survey data, this study examines the distribution characteristics of the floating population in Beijing, Tianjin and Hebei Region as well as the growth trend of the floating population in each region. It also makes assessments using floating population concentration and The Moran Index Computing Methods. According to the study, the spatial distribution of the floating population has a clear clustering pattern in Beijing, Tianjin and Hebei region. Beijing, Tianjin and Hebei region's mobile population growth patterns differ substantially, and the region's inflow population is mostly made up of migrant inhabitants of domestic provinces and inflow of people from nearby regions. Most of the mobile population resides in Beijing and Tianjin, whereas the outflow of people originates in Hebei province. The diffusion impact and the spatial features of the floating population in the Beijing, Tianjin and Hebei area have a constant, positive association, according to the timeline between 2014 and 2020.
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A meaningful topic that needs to be explored in the field of nonlinear waves is whether a neural network can reveal the phase transition of different types of waves and novel dynamical properties. In this paper, a physics-informed neural network (PINN) with parameters is used to explore the phase transition and time-varying dynamics of nonlinear waves of the (2+1)-dimensional Boussinesq equation describing the propagation of gravity waves on the surface of water. We embed the physical parameters into the neural network for this purpose. Via such algorithm, we find the exact boundary of the phase transition that distinguishes the periodic lump chain and transformed wave, and the inexact boundaries of the phase transition for various transformed waves are detected through PINNs with phase domain decomposition. In particular, based only on the simple soliton solution, we discover types of nonlinear waves as well as their interesting time-varying properties for the (2+1)-dimensional Boussinesq equation. We further investigate the stability by adding noise to the initial data. Finally, we perform the parameters discovery of the equation in the case of data with and without noise, respectively. Our paper introduces deep learning into the study of the phase transition of nonlinear waves and paves the way for intelligent explorations of the unknown properties of waves by means of the PINN technique with a simple solution and small data set.
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OBJECTIVE: To investigate the changes and functions of Sox2 gene expression and promoter methylation during induced differentiation of bone marrow mesenchymal stem cells (BMSCs) into hepatocytes (HCs). METHODS: Rat bone marrow Thy-1+Lin- cells were prepared and divided into control group (directed induction of differentiation into HCs) and experimental group (5-azacytidine intervention induced differentiation). The mRNA expression levels of ALB and Sox2 were detected by fluorescence quantitative polymerase chain reaction (PCR), and the Sox2 gene promoter methylation level was determined by Bisulfite sequencing PCR (BSP). RESULTS: Sox mRNA expression level was significantly increased in experimental group compared to the control group at 0, 7, and 14 days, respectively (all P<0.05). The Sox2 promoter methylation level was gradually increased after 0, 7 and 14 days induction in both groups, accompanied by an increase in methylated loci (all P<0.05). Statistical significance was present in CpG methylated loci between groups (all P<0.05). CONCLUSIONS: The expression of Sox2 gene increased first and then decreased in the process of inducing rat BMSCs into stem cells, and the methylation level of CpG loci in the promoter region changed dynamically, with an increased overall methylation level. After 5-aza treatment, the Sox2 promoter was in a non-methylated state, and its mRNA expression increased, which hindered the cell differentiation.
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Deep-subwavelength features have a minimal impact on wave transport in all dielectric systems; thus the homogenization approach was commonly adopted. Recently, the breakdown of effective medium theory (EMT) for the incident wave near the total reflection (TR) angle was demonstrated in a deep-subwavelength dielectric multilayer. Additionally, anomalous transmission was reported at angles exceeding the TR angle when introducing disorder and was attributed to Anderson localization. Here we firstly demonstrated that the alleged anomalous transmission also occurs in the disorder-free case, illustrating that attributing anomalous transmission to Anderson localization deserves a more in-depth study. To clarify the underlying physics of this asserted anomalous transmission, Anderson localization and broken EMT, the incident angle dependent reflectivity and modes for ordered and disordered deep-subwavelength multilayers were investigated systematically. Actually, the EMT is still convincing and the anomalous transmission is reasonable after a simple correction. However, the anomalous transmission is more accessible and the permittivity correction is more imperative in the disordered system due to the Anderson localization. These findings can be expanded to other wave systems such as acoustic waves and matter waves, providing insight into EMT and deepening our understanding of the intriguing transport phenomena in deep subwavelength systems.