China’s marine-continental transitional facies shale gas resources are abundant with shale gas resources of about 19.8 trillion cubic meters, while the exploration and development of these shale gas ...resources are still in the initial stage. The Upper Permian Longtan coal series shale is one of the most important transitional shales in the Yangtze platform, China. In this study, the comprehensive methods of mineralogy and organic geochemistry are used to discuss the characteristic of organic matter and sedimentary environment of the Longtan coal series shale in western Guizhou Province, South China. The results show that (1) the total organic carbon (TOC) content of this shale ranges in 0.6%-28.21%, mainly in 3%-12%, indicating a “good-excellent” hydrocarbon source rock, and its vitrinite reflectance (Ro) ranges from 1.48% to 2.93%, indicating a high-overmature organic matter; (2) the organic matter in this shale is multiorigin, and most of them come from the terrestrial higher plant while the rest come from the plankton; (3) type index (TI) of organic matter is from -65 to 41, indicating most of the kerogens which are II1-III types; and (4) the sedimentary environment of this shale is dominated by suboxic-anoxic fresh water environment, which provides a favorable condition for the preservation of organic matter. In addition, the warm and humid climate during the Late Permian in the Yangtze platform promotes plant growth, and as a result, the Longtan coal series shale is rich in organic matter and has great potential of shale gas exploration and development.
With tremendous research advances in biomedical application, liquid metals (LM) also offer fantastic chemistry for synthesis of novel nano-composites. Herein, as a pioneering trial, litchi-shaped ...heterogeneous eutectic gallium indium-Au nanoparticles (EGaIn-Au NPs), served as effective radiosensitizer and photothermal agent for radio-photothermal cancer therapy, have been successfully prepared using in situ interfacial galvanic replacement reaction. The enhanced photothermal conversion efficiency and boosted radio-sensitization effect could be achieved with the reduction of Au nanodots onto the eutectic gallium indium (EGaIn) NPs surface. Most importantly, the growth of tumor could be effectively inhibited under the combined radio-photothermal therapy mediated by EGaIn-Au NPs. Inspired by this approach, in situ interfacial galvanic replacement reaction may open a novel strategy to fabricate LM-based nano-composite with advanced multi-functionalities.
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•A facile method to synthesize heterogeneous liquid metal-Au nano-composite.•The galvanic replacement reaction mechanism is proposed for the first time.•The in situ growth of Au nanodots can improve radio-photothermal effect.•The enhanced radio-photothermal effect can effectively achieve cancer therapy.
Objectives
Using MRSI as comparison, we aimed to explore the difference between amide proton transfer (APT) MRI and conventional semi-solid magnetization transfer ratio (MTR) MRI, and to investigate ...if molecular APT and structural MTR can provide complimentary information in assessing brain tumors.
Methods
Seventeen brain tumor patients and 17 age- and gender-matched volunteers were included and scanned with anatomical MRI, APT and MT-weighted MRI, and MRSI. Multi-voxel choline (Cho) and N-acetylaspartic acid (NAA) signals were quantified from MRSI and compared with MTR and MTR
asym(3.5ppm)
contrasts averaged from corresponding voxels. Correlations between contrasts were explored voxel-by-voxel by pooling values from all voxels into Pearson’s correlation analysis. Differences in correlation coefficients were tested with the Z-test (set at
p
<0.05).
Results
APT and MT provide good contrast and quantitative parameters in tumor imaging, as do the metabolite (Cho and NAA) maps. MTR
asym(3.5ppm)
significantly correlated with MTR (R=-0.61,
p
<0.0001), Cho (R=0.568,
p
<0.0001) and NAA (R=-0.619,
p
<0.0001) in tumors, and MTR also significantly correlated with Cho (R=-0.346,
p
<0.0001) and NAA (R=0.624,
p
<0.0001). In healthy volunteers, MTR
asym(3.5ppm)
was non-significantly correlated with MTR (R=-0.049,
p
=0.239), Cho (R=0.030,
p
=0.478) and NAA (R=-0.083,
p
=0.046). Significant correlations were found among MTR with Cho (R=0.199,
p
<0.0001) and NAA (R=0.263,
p
<0.0001) in the group of healthy volunteers with lower correlation R values than those in tumor patients.
Conclusions
APT and MT could provide independent and supplementary information for the comprehensive assessment of molecular and structural changes due to brain tumor cancerogenesis.
Key Points
• MTR
asym(3.5ppm)
positively correlated with Cho while negatively with NAA in tumors.
• MTR positively correlated with NAA while negatively with Cho in tumors.
• Combining APT/MT provides molecular and structural information similarly to MRSI.
Randomness and fluctuations in wind power output may cause changes in important parameters (e.g., grid frequency and voltage), which in turn affect the stable operation of a power system. However, ...owing to external factors (such as weather), there are often various anomalies in wind power data, such as missing numerical values and unreasonable data. This significantly affects the accuracy of wind power generation predictions and operational decisions. Therefore, developing and applying reliable wind power interpolation methods is important for promoting the sustainable development of the wind power industry. In this study, the causes of abnormal data in wind power generation were first analyzed from a practical perspective. Second, an improved complete ensemble empirical mode decomposition with adaptive noise (ICEEMDAN) method with a generative adversarial interpolation network (GAIN) network was proposed to preprocess wind power generation and interpolate missing wind power generation sub-components. Finally, a complete wind power generation time series was reconstructed. Compared to traditional methods, the proposed ICEEMDAN-GAIN combination interpolation model has a higher interpolation accuracy and can effectively reduce the error impact caused by wind power generation sequence fluctuations
Abstract
Background
Hyperglycaemia in pregnancy (HIP) is a common metabolic disorder that not only poses risks to maternal health but also associates with an increased risk of diabetes among ...offspring. Vertical transmission of microbiota may influence the offspring microbiome and subsequent glucose metabolism. However, the mechanism by which maternal gut microbiota may influence glucose metabolism of the offspring remains unclear and whether intervening microbiota vertical transmission could be used as a strategy to prevent diabetes in the offspring of mothers with HIP has not been investigated. So we blocked vertical transmission to investigate its effect on glucose metabolism in the offspring.
Results
We established a murine HIP model with a high-fat diet (HFD) and investigated the importance of vertical transmission of gut microbiota on the glucose metabolism of offspring via birth and nursing by blocking these events through caesarean section (C-section) and cross-fostering. After weaning, all offspring were fed a normal diet. Based on multi-omics analysis, biochemical and transcriptional assays, we found that the glucometabolic deficits in the mothers were subsequently ‘transmitted’ to the offspring. Meanwhile, the partial change in mothers’ gut microbial community induced by HIP could be transmitted to offspring, supported by the closed clustering of the microbial structure and composition between the offspring and their mothers. Further study showed that the microbiota vertical transmission was blocked by C-section and cross-fostering, which resulted in improved insulin sensitivity and islet function of the offspring of the mothers with HIP. These effects were correlated with changes in the relative abundances of specific bacteria and their metabolites, such as increased relative abundances of Bifidobacterium and short-chain fatty acids. In particular, gut microbial communities of offspring were closely related to those of their foster mothers but not their biological mothers, and the effect of cross-fostering on the offspring’s gut microbiota was more profound than that of C-section.
Conclusion
Our study demonstrates that the gut microbiota transmitted via birth and nursing are important contributors to the glucose metabolism phenotype in offspring.
Various regularization methods have been proposed for single-orientation quantitative susceptibility mapping (QSM), which is an ill-posed magnetic field to susceptibility source inverse problem. ...Noise amplification, a major issue in inverse problems, manifests as streaking artifacts and quantification errors in QSM and has not been comparatively evaluated in these algorithms. In this paper, various QSM methods were systematically categorized for noise analysis. Six representative QSM methods were selected from four categories: two non-Bayesian methods with alteration or approximation of the dipole kernel to overcome the ill conditioning; four Bayesian methods using a general mathematical prior or a specific physical structure prior to select a unique solution, and using a data fidelity term with or without noise weighting. The effects of noise in these QSM methods were evaluated by reconstruction errors in simulation and image quality in 50 consecutive human subjects. Bayesian QSM methods with noise weighting consistently reduced root mean squared errors in numerical simulations and increased image quality scores in the human brain images, when compared to non-Bayesian methods and to corresponding Bayesian methods without noise weighting (p ≤ 0.001). In summary, noise effects in QSM can be reduced using Bayesian methods with proper noise weighting.
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A facile approach towards the synthesis of a novel hierarchical sieve-like structure of mesoporous silica nanoparticle aggregates (hsMSNA) is reported using a centrifugal method at ...room temperature, based on the Kelvin-Helmholtz instability and soft-template method. The developed approach is simple and can potentially be applied for scaled-up preparation. Importantly, scanning electron microscopy, transmission electron microscopy, small-angle X-ray diffraction, and nitrogen adsorption-desorption experiments characterize the mesoporous silica as hsMSNA consisting of 40–100nm mesoporous silica nanoparticles piled at 1–2 μm cylindrical pores in sieve-like tissues. Further, various pore sizes and sieve-, mesh-, and vesicular-like structures can be obtained by adjusting the reaction conditions. The Brunauer-Emmett-Teller specific surface area is as large as 500 m2/g with a 47cm3/g pore volume, facilitating easy drug loading and delivery. Cytotoxicity assays show that the samples are not cytotoxic under a high concentration of 200 μg/mL. Finally, the high drug encapsulation efficiency and sustained release behaviors indicats the considerable potential of the hsMSNA as a drug delivery system in the field of nanomedicine.
Spectro-temporal receptive fields (STRFs) have been widely used as linear approximations to the signal transform from sound spectrograms to neural responses along the auditory pathway. Their ...dependence on statistical attributes of the stimuli, such as sound intensity, is usually explained by nonlinear mechanisms and models. Here, we apply an efficient coding principle which has been successfully used to understand receptive fields in early stages of visual processing, in order to provide a computational understanding of the STRFs. According to this principle, STRFs result from an optimal tradeoff between maximizing the sensory information the brain receives, and minimizing the cost of the neural activities required to represent and transmit this information. Both terms depend on the statistical properties of the sensory inputs and the noise that corrupts them. The STRFs should therefore depend on the input power spectrum and the signal-to-noise ratio, which is assumed to increase with input intensity. We analytically derive the optimal STRFs when signal and noise are approximated as Gaussians. Under the constraint that they should be spectro-temporally local, the STRFs are predicted to adapt from being band-pass to low-pass filters as the input intensity reduces, or the input correlation becomes longer range in sound frequency or time. These predictions qualitatively match physiological observations. Our prediction as to how the STRFs should be determined by the input power spectrum could readily be tested, since this spectrum depends on the stimulus ensemble. The potentials and limitations of the efficient coding principle are discussed.
The mechanism of biocontrol agent Saccharothrix yanglingensis Hhs.015 action against Valsa mali, a major apple Valsa canker pathogen, was examined using a novel, sensitive (minimum detection limit ...100 pg/μL) and reliably RT-qPCR technique. Prior to lesion formation, total concentration of V. mali in the bark showed a significant decrease (p<0.05) after 24 h of Hhs.015 treatment. This was more pronounced at 48 and 96 h post treatment. After lesion formation, levels of V. mali remained constant at the boundary between infected and uninfected bark tissues, although the relative expansion rate of the lesion was significantly reduced (p<0.05). Gene expression levels of endo-polygalacturonase, a marker for fungal pathogenicity, were sharply reduced while host induced resistance callose synthase levels increased significantly (p<0.05) at the boundary bark at 9 d after Hhs.015 treatment. The results showed that biocontrol agent Hhs.015 prevented infection of V. mali by inhibiting pathogen growth, down-regulating pathogenicity factor expression and inducing a high level of host resistance.
Bimetallic nanozymes have been emerging as essential catalysts due to their unique physicochemical properties from the monometallics. However, the access to optimize catalytic performance is often ...limited by the thermodynamic immiscibility and also heterogeneity. Thus, we present a one-step coreduction strategy to prepare the miscible Cu–Pd bimetallic nanozymes with controllable shape and homogeneously alloyed structure. The homogeneity is systematically explored and luckily, the homogeneous introduction of Cu successfully endows Cu–Pd bimetallic nanozymes with enhanced Fenton-like efficiency. Density functional theory (DFT) theoretical calculation reveals that Cu–Pd bimetallic nanozymes exhibit smaller d-band center compared with Pd nanozymes. Easier adsorption of H
2
O
2
molecular contributed by the electronic structure of Cu significantly accelerate the catalytic process together with the strong repulsive interaction between H atom and Pd atom.
In vitro
cytotoxicity and intracellular ROS generation performance reveal the potential for
in vivo
biocatalysis. The strategy to construct kinetically miscible Cu–Pd bimetallic nanozymes will guide the development of bimetallic catalysts with excellent Fenton-like efficiency for biocatalytic nanomedicine.
One-step coreduction strategy is performed to synthesize kinetically miscible and homogeneously alloyed Cu–Pd bimetallic nanozymes with enhanced Fenton-like efficiency for biocatalysis.
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