ExtraTrees-hidden Markov model based equalizer for mode division multiplexing ring-core fiber communication with non-orthogonal MultiCAP modulation.

This paper presents an orbital angular momentum mode division multiplexing (OAM-MDM) ring-core fiber transmission method based on non-orthogonal multiband carrierless amplitude and phase (NMCAP) modulation with an extremely randomized trees-hidden Markov model (ExtraTrees-HMM)-based equalizer. The ExtraTrees-HMM equalizer uses the statistical characteristics of the received distorted signals to model the nonlinear channel of the system to classify these distorted signals into corresponding constellation classes. Experiments were conducted using a 216 Gbit/s OAM-MDM NMCAP modulation optical fiber communication system with 2 km ring-core fiber transmission and the results show that compared with a conventional Volterra nonlinear equalizer (VNE), the proposed ExtraTrees-HMM equalizer could improve the receiver sensitivity by 1 dB for OAM mode l = + 2, and 0.6 dB for OAM mode l = + 3. In addition, the computational complexity of the proposed equalizer was reduced by 43.94% compared with the VNE. In brief, the ExtraTrees-HMM is a promising equalization candidate for ultra-high-capacity inter-data-center interconnections.

Underlying mechanisms governing on distribution and stratification of DOM during seasonal freeze-thaw cycles.

During the freeze-thaw cycles of ice-covered lakes, DOM undergoes a series of transformations including enrichment, dispersion, and filtration. However, the mechanisms and influence factors on lake pollution processes remain unclear. Therefore, this study investigates the distribution of DOM components and elucidate the role of ice-layer sieving its mechanisms within ice-water-sediments. Study identifies significant variations in the characteristics of DOM, protein-like substances tend to migrate towards the ice layer, while humic-like substances predominantly remain in water. This selective distribution is primarily influenced by the physical and chemical properties of DOM during the freezing process. The ice layer acts as a sieve, allowing smaller molecules such as protein-like substances to pass through more easily, while larger molecules like humic-like substances are retained in the water. Additionally, Temperature plays a pivotal role in affecting the contents of DOM. As the temperature decreases, the solubility of DOM decreases, leading to its precipitation and enrichment in sediments. Conversely, an increase in temperature can facilitate the release of DOM from sediments into the water. Furthermore, high content of total dissolved solids can affect the solubility and stability of DOM, potentially leading to changes in its composition and distribution. These insights provide a deeper understanding of the complex interplay between thermal processes and chemical dynamics within ice-covered aquatic environments. They offered valuable insights into the behavior of organic pollutants in frozen lake systems. The findings have potential implications for environmental management strategies aimed at mitigating the effects of climate.

Genesis and Accumulation Mechanism of Low-Rank CBM: A Case Study in the Jiergalangtu Block of Erlian Basin, Northern China.

In order to elucidate the origin of coalbed methane (CBM) in the Jiergalangtu block of Erlian Basin, Inner Mongolia of China, gas components, stable isotope tests of 22 gas samples, radioisotope dating measurements, and water quality analysis of 15 coproduced water samples were evaluated. On account of the geochemical data and genetic indicators, including C1/C1-n, C1/(C2 + C3), and CO2/(CO2 + CH4) (CDMI) values, δ13C(CO2), Δδ13C(CO2-CH4), δ15N, and 3He/4He combined with vitrinite reflectance (Ro) (0.29-0.48%, avg. 0.35%) of Saihantala formation, the results indicate that methane in the Jiergalangtu block is mostly dominated by primary and secondary biological gas, 40.91% of the gas samples are secondary biogas and primary biogas accounts for 59.19%. Among them, methyl-type fermentation accounts for 31.82%, and carbon dioxide (CO2) reduction makes up 68.18%. CO2 reduction generally occurs region-wide but is mainly associated with the central part of the block, where CO2 depletion and 13C enrichment take place correspondingly. Methane and CO2 δ13C almost tend to isotopically light along the margin of the block, indicating that gas generation is significantly affected by the methyl-type fermentation pathway. Meanwhile, the genesis analysis of other gas components in CBM is also investigated, CO2 is mainly the associated product of microbial methanogenesis, and nitrogen (N2) is primarily from the atmosphere with a little amount from the earth's crust. Furthermore, the formation time of coalbed water has been dissected based on the hydrogeochemical properties of the coproduced water samples. The coalbed water exhibit a Na-HCO3 and Na-HCO3-Cl type and have a total dissolved solid (TDS) value ranging from 2458.58 to 5579.1 mg/L, with an average of 3440.55 mg/L. Moreover, comprehensive analysis of δD(H2O), δ18O(H2O), δ13CDIC, and the radioisotope dating index [3H, 14C(Fm) and 14C(BP)] indicates that the coalbed water was formed in the Quaternary Pleistocene and rarely replenished by the present surface water. The mechanism of CBM accumulation is basically sorted out by synthesizing the history of burial, heat, and hydrocarbon generation. The CBM formation can be divided into four stages. That is, microbial gas production approximately began at the beginning of the Early Cretaceous and reached the peak of thermogenic gas production in the middle and late Early Cretaceous. At the end of the Early Cretaceous, strata possibly began to uplift, and denudation led to gas escape. From Neogene to Pleistocene, glacial meltwater tended to penetrate into coalbed on a large scale, and N2 and CO2 also entered the coal seams, stimulating abundant secondary biological gas generation. Since Holocene, geological conditions including temperature and TDS have become hostile to biogas generation, and biogas generation tends to stop. Therefore, the Jiergalangtu block mainly represents sealed primary biological gas and secondary biological gas in CBM reservoirs.

Ultra-low complexity random forest for optical fiber communications.

In this paper, we present an efficient equalizer based on random forest for channel equalization in optical fiber communication systems. The results are experimentally demonstrated in a 120 Gb/s, 375 km, dual-polarization 64-quadrature magnitude modulation (QAM) optical fiber communication platform. Based on the optimal parameters, we choose a series of deep learning algorithms for comparison. We find that random forest has the same level of equalization performance as deep neural networks as well as lower computational complexity. Moreover, we propose a two-step classification mechanism. We first divide the constellation points into two regions and then use different random forest equalizers to compensate the points in different regions. Based on this strategy, the system complexity and performance can be further reduced and improved. Furthermore, due to the plurality voting mechanism and two-stage classification strategy, the random forest-based equalizer can be applied to actual optical fiber communication systems.

Nε-(carboxymethyl)lysine promotes lipid uptake of macrophage via cluster of differentiation 36 and receptor for advanced glycation end products.

BACKGROUND: Advanced glycation end products (AGEs) are diabetic metabolic toxic products that cannot be ignored. Nε-(carboxymethyl)lysine (CML), a component of AGEs, could increase macrophage lipid uptake, promote foam cell formation, and thereby accelerate atherosclerosis. The receptor for AGEs (RAGE) and cluster of differentiation 36 (CD36) were the receptors of CML. However, it is still unknown whether RAGE and CD36 play key roles in CML-promoted lipid uptake. AIM: Our study aimed to explore the role of RAGE and CD36 in CML-induced mac-rophage lipid uptake. METHODS: In this study, we examined the effect of CML on lipid uptake by Raw264.7 macrophages. After adding 10 mmol/L CML, the lipid accumulation in macro-phages was confirmed by oil red O staining. Expression changes of CD36 and RAGE were detected with immunoblotting and quantitative real-time polymerase chain reaction. The interaction between CML with CD36 and RAGE was verified by immunoprecipitation. We synthesized a novel N-succinimidyl-4-18F-fluorobenzoate-CML radioactive probe. Radioactive receptor-ligand binding assays were performed to test the binding affinity between CML with CD36 and RAGE. The effects of blocking CD36 or RAGE on CML-promoting lipid uptake were also detected. RESULTS: The study revealed that CML significantly promoted lipid uptake by macro-phages. Immunoprecipitation and radioactive receptor-ligand binding assays indicated that CML could specifically bind to both CD36 and RAGE. CML had a higher affinity for CD36 than RAGE. ARG82, ASN71, and THR70 were the potential interacting amino acids that CD36 binds to CML Anti-CD36 and anti-RAGE could block the uptake of CML by macrophages. The lipid uptake promotion effect of CML was significantly attenuated after blocking CD36 or RAGE. CONCLUSION: Our results suggest that the binding of CML with CD36 and RAGE promotes macrophage lipid uptake.

Coalbed Methane Enrichment Characteristics and Exploration Target Selection in the Zhuozishan Coalfield of the Western Ordos Basin, China.

The Zhuozishan coalfield at the western margin of the Ordos Basin is one of the main coal-mining areas in China, and recent explorations have revealed the great potential for coalbed methane (CBM) resources in its Carboniferous and Permian strata. In this paper, the controlling factors of CBM enrichment of the major coals are studied in this coalfield and the CBM resources are estimated based on the analysis of the coal petrology and compilation of literature data on the gas content. The result of the coal petrology analysis of 10 samples shows that the vitrinite content of No. 16 coal (71.9-77.3%) is higher than that of No. 9 coal (59.1-65.1%), and the inertinite content of No. 16 coal (18.9-23.5%) is lower than that of No. 9 coal (30.1-34.9%). The R o,max value of No. 16 coal (1.18-1.35%) is higher than that of No. 9 coal (1.04-1.13%), and both coals are of medium rank. Due to greater thickness, deeper burial depth, and better coal petrology characteristics, the No. 16 coal seam of the Taiyuan Formation is selected as the major coal seam for CBM resource estimation, which has a thickness of 1-6 m and a present-day burial depth of 200-1100 m. The gas content of this coal seam varies mostly between 4 and 10 m3/t. Positive correlation between the coal seam thickness as well as present-day burial depth and the gas content suggests that the thick and deeply buried coal seams are favorable for CBM preservation. The ash yield shows an insignificant negative correlation with the gas content, indicating that ash yield is not an important factor for CBM enrichment. The syncline hinges located below the thrust zones show higher gas content due to greater burial depths. In contrast, the anticline hinges at shallower depths tend to have lower gas contents. Based on the combined information about sedimentary environments, structural patterns, and hydrogeology, two CBM accumulation models are put forward in the study area that include syncline-hydraulic plugging below thrust nappe and fault-confined aquifer plugging. The volumetric method is used to estimate the CBM resources, and results indicate that the CBM resource in the whole coalfield is 428.78 × 108 m3, and the total resource abundance is 0.74 × 108 m3/km2. Two favorable areas for the CBM exploration are optimized based on the resource amount and resource abundance. One of the favorable areas is the Kabuqi area in the northern part of the coalfield, and another is the Baiyunwusu area in the central part of the coalfield. These two areas will be the CBM priority exploration areas at the western margin of the Ordos Basin.

Relationship Between the Triglyceride-Glucose Index and Type 2 Diabetic Macroangiopathy: A Single-Center Retrospective Analysis.

Purpose: The research explores the relationship between the triglyceride-glucose index (TyG index) and the macroangiopathy risk in single-center hospitalized type 2 diabetes mellitus (T2DM) patients and develops a risk prediction nomogram model. Patients and Methods: A total of 858 patients with T2DM were studied retrospectively. Lasso regression was used to eliminate unimportant factors, and multivariate logistic regression analysis was used to investigate the association between the TyG index and macrovascular disease in T2DM. A nomogram model was constructed to predict macrovascular disease in T2DM and tested using the bootstrap technique, and the efficacy of the nomogram model was investigated using ROC curves. The multivariate Cox proportional hazards model estimated the association between the TyG index and all-cause mortality. Results: TyG index, high-density lipoprotein, red blood cell count, hypertension, history of taking ACEI/ARB drugs, and aortic calcification were closely related to macrovascular complications. In Cox proportional hazard model, the HRs of TyG index were 1.89 (95% confidence interval (CI) 1.29-2.76, p < 0.001) after adjusting for covariates. The risk of all-cause mortality in T2DM with macrovascular complications was significantly higher than in diabetic patients without vascular disease. In the ROC curve analysis, the cut-off value of the TyG index for macrovascular complications of T2DM was 9.31 (AUC: 0.702, 95% CI 0.67-0.74, p < 0.001). Conclusion: TyG index predicts future macrovascular disease in diabetic patients independently of known cardiovascular risk factors, suggesting that TyG index may be a useful marker for prognosis in diabetic patients.

Mitigating the ambiguity problem in the CNN-based wavefront correction.

In this work, we propose an attention-based adaptive optics method that uses a non-local block to integrate phase diversity with a convolutional neural network (CNN). The simulation results showcase the effectiveness of the proposed method to mitigate the ambiguity problem of phase retrieval and better performance than traditional CNN-based wavefront correction.

Chaotic physical layer encryption scheme based on phase ambiguity for a DMT system.

Chaotic encryption is a promising scheme for physical layer security. By solving the multi-dimensional chaotic equations and transforming the obtained results, both bit-level and symbol-level encryption can be realized. One of the mainstream symbol-level encryption solutions is the constellation shifting (CS) scheme, which treats the chaotic sequence as artificial noise and adds it to the QAM signal sequence to achieve encryption. However, this scheme has several technical flaws in practical application, in terms of computational complexity and coexistence with blind equalization algorithm and the probabilistic shaping (PS) technique. In this paper, we propose a novel symbol-level encryption scheme based on phase ambiguity (PA), which converts the two sequences originally used to generate artificial noise into a set of phase rotation keys and complex conjugate keys, so that the encrypted symbols are still on the ideal constellation point coordinates. Simulation verification is carried out in a discrete multi-tone (DMT) system with 64QAM modulation. Results show that the proposed scheme can fully retain the shaping gain brought by the PS technique and avoid the error convergence of the blind equalizer. Moreover, the time required to solve the chaotic equations is only 38% of the CS scheme. Experimental verification is carried out, and the obtained results once again prove the superiority of the proposed encryption algorithm, which is a practical alternative for future physical layer secure optical communications.

[Bioinformatics analysis identifies aging/senescence-induced genes in calcified plaques].

Vascular calcification is an important pathophysiological basis of cardiovascular disease with its underlying mechanism unclear. In recent years, studies have shown that aging is one of the risk factors for vascular calcification. The purpose of this study was to investigate the microenvironmental characteristics of vascular calcification, identify aging/senescence-induced genes (ASIGs) closely related to calcified plaques, and explore the evolution trajectory of vascular calcification cell subsets. Based on the bioinformatics method, the single cell transcriptome sequencing data (Gene Expression Omnibus: GSE159677) of carotid artery samples from 3 patients undergoing carotid endarterectomy were grouped and annotated. Vascular calcification-related aging genes were identified by ASIGs data set. The pseudotime trend of ASIGs in cell subsets was analyzed by Monocle 3, and the evolution of vascular calcification cells was revealed. After quality control, all cells were divided into 8 cell types, including B cells, T cells, smooth muscle cells, macrophages, endothelial cells, fibroblasts, mast cells, and progenitor cells. Ten ASIGs related to vascular calcification were screened from the data set of ASIGs, which include genes encoding complement C1qA (C1QA), superoxide dismutase 3 (SOD3), lysozyme (LYZ), insulin-like growth factor binding protein-7 (IGFBP7), complement C1qB (C1QB), complement C1qC (C1QC), Caveolin 1 (CAV1), von Willebrand factor (vWF), clusterin (CLU), and αB-crystallin (CRYAB). Pseudotime analysis showed that all cell subsets were involved in the progression of vascular calcification, and these ASIGs may play an important role in cell evolution. In summary, AGIS plays an important role in the progression of vascular calcification, and these high expression genes may provide ideas for early diagnosis and treatment of vascular calcification.

Epidemiological Research Advances in Vascular Calcification in Diabetes.

Vascular calcification is the transformation of arterial wall mesenchymal cells, particularly smooth muscle cells (SMCs), into osteoblast phenotypes by various pathological factors. Additionally, vascular transformation mediates the abnormal deposition of calcium salts in the vascular wall, such as intimal and media calcification. Various pathological types have been described, such as calcification and valve calcification. The incidence of vascular calcification in patients with diabetes is much higher than that in nondiabetic patients, representing a critical cause of cardiovascular events in patients with diabetes. Because basic research on the clinical transformation of vascular calcification has yet to be conducted, this study systematically expounds on the risk factors for vascular calcification, vascular bed differences, sex differences, ethnic differences, diagnosis, severity assessments, and treatments to facilitate the identification of a new entry point for basic research and subsequent clinical transformation regarding vascular calcification and corresponding clinical evaluation strategies.

Role of NFAT in the Progression of Diabetic Atherosclerosis.

Nuclear factor of activated T cells (NFAT) is a transcription factor with a multidirectional regulatory function, that is widely expressed in immune cells, including cells in the cardiovascular system, and non-immune cells. A large number of studies have confirmed that calcineurin/NFAT signal transduction is very important in the development of vascular system and cardiovascular system during embryonic development, and plays some role in the occurrence of vascular diseases such as atherosclerosis, vascular calcification, and hypertension. Recent in vitro and in vivo studies have shown that NFAT proteins and their activation in the nucleus and binding to DNA-related sites can easily ɨnduce the expression of downstream target genes that participate in the proliferation, migration, angiogenesis, and vascular inflammation of vascular wall related cells in various pathophysiological states. NFAT expression is regulated by various signaling pathways, including CD137-CD137L, and OX40-OX40L pathways. As a functionally diverse transcription factor, NFAT interacts with a large number of signaling molecules to modulate intracellular and extracellular signaling pathways. These NFAT-centered signaling pathways play important regulatory roles in the progression of atherosclerosis, such as in vascular smooth muscle cell phenotypic transition and migration, endothelial cell injury, macrophage-derived foam cell formation, and plaque calcification. NFAT and related signaling pathways provide new therapeutic targets for vascular diseases such as atherosclerosis. Hence, further studies of the mechanism of NFAT in the occurrence and evolution of atherosclerosis remain crucial.