Joint inversion of receiver functions and surface waves with enhanced preconditioning on densely distributed CNDSN stations: Crustal and upper mantle structure beneath China

We present shear wave velocity structure beneath China by joint modeling of teleseismic receiver function and Rayleigh wave group velocity dispersion data observed at +1000 permanent broadband seismic stations in the Chinese National Digital Seismic Network (CNDSN). A ray-parameter-based stacking method is employed to minimize artifacts in stacking receiver functions from different sources. The Rayleigh wave dispersion curve is extracted from group velocity tomographic models at all applicable periods. Enhanced preconditions are applied on the linearized iterative inversion to regularize and balance multiple types of data. The velocity profile inversion at each station starts from an initial model derived from sediments, crustal thickness, Vp/Vs ratio and Pn/Sn models. This multistep approach not only reduces uncertainty and nonuniqueness of the velocity inversion but also efficiently fills information gap in each data set. We then generate a 3-D S velocity model by combining and smoothing all the 1-D models. The obtained 3-D model reveals crustal and upper mantle velocity structures that are well correlated with tectonic features of China, for example, our model shows a clear east-west bimodal distribution at 35 km deep, low velocity in the crust beneath central and eastern Tibetan plateau, and sedimentary structure in major cratons and basins. Our model is consistent with existing tomographic models in large scale but provides more structural details in regional and local scales

Theoretical bound of the efficiency of learning

A unified thermodynamic formalism describing the efficiency of learning is proposed. First, we derive an inequality, which is more strength than Clausius's inequality, revealing the lower bound of the entropy-production rate of a subsystem. Second, the inequality is transformed to determine the general upper limit for the efficiency of learning. In particular, we exemplify the bound of the efficiency in nonequilibrium quantum-dot systems and networks of living cells. The framework provides a fundamental trade-off relationship between energy and information inheriting in stochastic thermodynamic processes

Intraplate volcanism controlled by back-arc and continental structures in NE Asia inferred from transdimensional Bayesian ambient noise tomography

Intraplate volcanism adjacent to active continental margins is not simply explained by plate tectonics or plume interaction. Recent volcanoes in northeast (NE) Asia, including NE China and the Korean Peninsula, are characterized by heterogeneous tectonic structures and geochemical compositions. Here we apply a transdimensional Bayesian tomography to estimate high-resolution images of group and phase velocity variations (with periods between 8 and 70 s). The method provides robust estimations of velocity maps, and the reliability of results is tested through carefully designed synthetic recovery experiments. Our maps reveal two sublithospheric low-velocity anomalies that connect back-arc regions (in Japan and Ryukyu Trench) with current margins of continental lithosphere where the volcanoes are distributed. Combined with evidences from previous geochemical and geophysical studies, we argue that the volcanoes are related to the low-velocity structures associated with back-arc processes and preexisting continental lithosphere

Multistep modelling of teleseismic receiver functions combined with constraints from seismic tomography: Crustal structure beneath southeast China

With a growing number of modern broad-band seismographic stations in Asia, the conditions have improved to allow higher resolution structural studies on regional scales. Here, we perform a receiver-based study of the lithosphere of southeast China using waveform records of excellent quality from 14 Chinese National Digital Seismic Network and four Global Seismic Network stations. Calculating the theoretical receiver functions (RFs) that match the observed RFs from teleseismic waveforms is an established technique for retrieving information about crustal and upper mantle structure beneath a seismic receiver. RFs, however, are predominantly sensitive to the gradients in the lithospheric elastic parameters, and it is impossible to determine a non-unique distribution of seismic parameters such as absolute shear wave speeds as a function of depth unless other geophysical data are combined with RFs. Thus, we combine RFs with independent information from shear and compressional wave speeds above and below the Mohorovičić discontinuity, available from the existing tomographic studies. We introduce a statistical approach for automatically selecting only mutually coherent RFs from a large set of observed waveforms. Furthermore, an interactive forward modelling software is introduced and applied to observed RFs to define a prior, physically acceptable range of elastic parameters in the lithosphere. This is followed by a grid-search for a simple crustal structure. An initial model for a linearized, iterative inversion is constructed from multiple constraints, including results from the grid-search for shear wave speed, the Moho depth versus vp/vs ratio domain search and tomography. The thickness of the crust constrained by our multistep approach appears to be more variable in comparison with tomographic studies, with the crust thinning significantly towards the east. We observe low values of vp/vs ratios across the entire region, which indicates the presence of a very silicic crust. We do not observe any correlation between the crustal thickness or age of the crust with vp/vs ratios, which argues against a notion that there is a simple relationship between mineralogical composition and crustal thickness and age on a global scale

Effect of sodium butyrate on glucose and lipid metabolism, insulin expression and apoptosis of β-cells in obese pregnant rats

Purpose: To study the influence of sodium butyrate on the metabolism of lipid and glucose, insulin expression and apoptosis of β-cells in obese pregnant rats. Methods: Three groups of one hundred and twenty 4-week-old female C5BL/6J mice were used: control, high-fat diet and sodium butyrate groups. Insulin, triglycerides and total cholesterol were evaluated by enzyme-linked immunosorbent assay (ELISA). Insulin levels, as well as area and quality of islet β-cells were assessed using Image Pro Plus software. The number of DAPI-positive islet cells, positive expression of bcl-2 in each islet cell, and apoptosis of islet β-cells in each group were determined. Results: The expression levels of insulin in high-fat diet group and butyrate group were significantly reduced, relative to control, but insulin expression level in Na butyrate group increased, relative to high- fat diet mice (p < 0.01). The area and quality of islet β-cells in high-fat diet and sodium butyrate groups were markedly higher in sodium butyrate group than in high-fat diet group (p < 0.01). The bcl-2 expression in islet β-cells rose in mice given high-fat diet, relative to control and sodium butyrate groups (p < 0.01). Conclusion: Sodium butyrate facilitates glucose and lipid metabolism, but increases insulin expression, and effectively inhibits apoptosis of islet β-cells in obese pregnant mice. Thus, sodium butyrate may be useful in the prevention and treatment of metabolic disorders due to diabetes mellitus (DM)

Study on Qi Deficiency Syndrome Identification Modes of Coronary Heart Disease Based on Metabolomic Biomarkers

Coronary heart disease (CHD) is one of the most important types of heart disease because of its high incidence and mortality. With the era of systems biology bursting into reality, the analysis of the whole biological systems whether they are cells, tissues, organs, or the whole organisms has now become the norm of biological researches. Metabolomics is the branch of science concerned with the quantitative understandings of the metabolite complement of integrated living systems and their dynamic responses to the changes of both endogenous and exogenous factors. The aim of this study is to discuss the characteristics of plasma metabolites in CHD patients and CHD Qi deficiency syndrome patients and explore the composition and concentration changes of the plasma metabolomic biomarkers. The results show that 25 characteristic metabolites related to the CHD patients comparing with the healthy people, and 4 identifiable variables had significant differences between Qi deficiency and non-Qi deficiency patients. On the basis of identifying the different plasma endogenous metabolites between CHD patients and healthy people, we further prompted the metabolic rules, pathogenesis, and biological essence in Qi deficiency syndrome patients

Multifactor dimensionality reduction analysis of syndrome characteristics of chronic persistent asthma

AbstractObjectiveTo analyze the syndrome characteristics in patients with chronic persistent asthma.Methods365 patients (121 males, 244 females, 60.8 ± 29.1 years old) with chronic persistent asthma were enrolled in this cross-sectional study. The information of syndrome, symptoms, signs, tongue coating and pulse were collected from all patients. The syndrome characteristics of chronic persistent asthma were examined through the multifactor dimensionality reduction (MDR) analysis and the results were verified by the Chi-square test.ResultsThe results of the MDR analysis and the Chi-square test showed the following positive correlation of the interaction among: the deficiency syndrome of the lung and spleen and deep pulse, disinclination to talk due to lack of qi, fatigue, lassitude and thick tongue coating; the deficiency syndrome of the lung and kidney and dizziness and disinclination to talk due to lack of qi, fatigue, lassitude and pallid complexion; the syndrome of phlegm-heat obstructing the lung and rapid pulse, abdominal distension, disinclination to talk due to lack of qi, frequent urination and lassitude; the syndrome of phlegm-dampness obstructing the lung and disinclination to talk due to lack of qi, greasy coating, fatigue and lassitude. (P < .05 for all).ConclusionThe syndrome of chronic persistent asthma is characterized by fatigue and lassitude due to dysfunction of the lung, spleen and kidney

The Change of Immunoactivity of Dendritic Cells Induced by Mouse 4-1BBL Recombinant Adenovirus

*These authors contributed equally to this work. ∙The authors have no financial conflicts of interest. Purpose: The purpose of this study is to construct a recombinant adenovirus vector carrying mouse 4-1BBL and observe its effects in dendritic cells. Materials and Methods: Mouse 4-1BBL cDNA was taken from the plasmid pcDNA3-m4-1BBL and subcloned into adenovirus shuttle plasmid pAdTrack-CMV, and then transformed into competent BJ5183 with plasmid pAdEasy-1. After recombination in E. coli, Ad-4-1BBL was packaged and amplified in HEK 293 cells. The expression of 4-1BBL in Ad-4-1BBL-transfected mouse prostate cancer cell line RM-1 was detected by reverse transcription polymerase chain reaction (RT-PCR) and Western blot. After the co-culture of dendritic cells (DCs) with Ad-4-1BBLtransfected RM-1 cells, interleukin (IL)-6 and IL-12 production were assessed by enzyme-linked immunosorbent assay (ELISA) and co-stimulatary moleculs (CD80 and CD86) on DCs were analyzed by flow cytometry. Results: The levels of IL-6 (3,960 pg/mL) and IL-12 (249 pg/mL) production in Ad-m4-1BBL-pulsed DCs were more than those in none-pulsed DCs. The differences were statistically significant (p &lt; 0.05). The expression of co-stimulatary molecules (CD80 and CD86) was up-regulated in Ad-m4-1BBL-pulsed DCs. Conclusion: The results indicated the recombinant mouse 4-1BBL can effectively activate DCs

Accuracy of triage strategies for human papillomavirus DNA-positive women in low-resource settings: A cross-sectional study in China

CareHPV is a human papillomavirus (HPV) DNA test for low-resource settings (LRS). This study assesses optimum triage strategies for careHPV-positive women in LRS