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C-Glycosyl peptides/proteins are metabolically stable mimics of the native glycopeptides/proteins bearing O/N-glycosidic linkages, and are thus of great therapeutical potential. Herein, we disclose a protocol for the syntheses of vinyl C-glycosyl amino acids and peptides, employing a nickel-catalyzed reductive hydroglycosylation reaction of alkyne derivatives of amino acids and peptides with common glycosyl bromides. It accommodates a wide scope of the coupling partners, including complex oligosaccharide and peptide substrates. The resultant vinyl C-glycosyl amino acids and peptides, which bear common O/N-protecting groups, are amenable to further transformations, including elongation of the peptide and saccharide chains., C-Glycosyl peptides/proteins are metabolically stable mimics of the native glycopeptides/proteins of great therapeutic potential, but their chemical synthesis is challenging. Here, the authors report a protocol for the synthesis of vinyl C-glycosyl amino acids and peptides, via a Ni-catalyzed reductive hydroglycosylation reaction of alkyne derivatives of amino acids and peptides with glycosyl bromides.

It has been confirmed by comparison with particle velocities of surface waves of wave normal perpendicular to borehole axis measured by collocated seismic broadband array or borehole seismometers that high-sensitivity borehole tensor strainmeters could measure surface strain waves qualitatively. However, quantitative measurability of strain waves of wave normal being oblique to borehole axis by borehole tensor strainmeters is still a challenging problem. In this article, we introduce a scattering model of oblique-incidence seismic waves by an empty borehole to investigate the influence of incident-wave normal and polarization on theoretical-frequency-response bandwidth of borehole tensor strainmeters. Within the theoretical bandwidth of borehole tensor strainmeters, zero-frequency gains are introduced to build quantitative relation between instrumental strain waves of borehole tensor strainmeters and oblique-incidence seismic strain waves. Better understanding the influence of incident-wave normal and polarization on the relation between instrumental strain and strain components induced by the incident strain wave shows that incident-wave normal and polarization must be assessed by other instrumentation to promise quantitative measurement of incident strain waves by borehole tensor strainmeters, which would benefit in situ calibration of borehole tensor strainmeters.

Borehole tensor strainmeters such as the RZB tensor strainmeter, YRY tensor strainmeter, and Gladwin tensor strainmeter are highly sensitive to ground deformation over periods of minutes to months, bridging the gap in the sensitivity and frequency between Global Positioning System and seismic measurements. To discuss the possibility of quantitatively measuring seismic strain waves by borehole tensor strainmeters, a model of the scattering of plane elastic P and S waves by an empty borehole is introduced to investigate the theoretical frequency response and corresponding bandwidth of an empty borehole for borehole tensor strainmeters. The calculation of scattering waves around the empty borehole gives the changes in the diameter of the borehole. Different gauge combinations are introduced to reflect the areal strain and the maximum shear strain of the incident waves. The theoretical frequency responses for different gauge combinations are determined by the nondimensional wavenumber of the incident wave, the Poisson’s ratio of the surrounding rock, and the difference between the azimuth angle of the first gauge and the incident angle of the incident wave. Theoretical‐frequency‐response analysis of different gauge combinations for an empty borehole confirms that different gauge combinations serve as low‐pass filters. The 1% bandwidth of the gauge combinations shows that borehole tensor strainmeters could quantitatively measure seismic strain waves in the acoustic frequency range if the instrumental effective bandwidth of the gauge is sufficiently large, which will advance high‐frequency seismology and benefit in situ calibration of borehole tensor strainmeters.

In this paper, a sentiment analysis model based on the bi-directional GRU, Attention and Capusle fusion of BI-GRU+Attention+Capsule was designed and implemented based on the sentiment analysis task of the open film review data set IMDB, and combined with the bi-directional GRU, Attention and Capsule. It is compared with six deep learning models, such as LSTM, CNN, GRU, BI-GRU, CNN+GRU and GRU+CNN. The experimental results show that the accuracy of the BI-GRU model combined with Attention and Capusule is higher than the other six models, and the accuracy of the GRU+CNN model is higher than that of the CNN+GRU model, and the accuracy of the CNN+GRU model is higher than that of the CNN model. The accuracy of CNN model was successively higher than that of LSTM, BI-GRU and GRU model. The fusion model of BI-GRU +Attention+Capsule adopted in this paper has the highest accuracy among all the models. In conclusion, the fusion model of BI-GRU+Attention+Capsule effectively improves the accuracy of text sentiment classification.

A highly effective and versatile glycosylation method is developed, which uses 3,5-dimethyl-4-(2'-phenylethynylphenyl)phenyl (EPP) glycosides as donors and NIS/TMSOTf as promoter and proceeds via an unprecedented dearomative activation mechanism.

In this paper, we introduce a novel model called BGAC for text semantic analysis task. The proposed network is a new integration of two Bi-GRU, self-Attention mechanism and Capsule network architecture. In our experiment on the task of sentiment analysis in dataset IMDB (a public film review dataset), our model achieve the state-of-the-art results. We compare it with six other deep learning models, such as LSTM, CNN, GRU, BI-GRU, CNN+GRU and GRU+CNN. The results of the experiments show that the experimental effect of the bidirectional GRU fusion self-attention mechanism and the capsule network outperforms than the other six neural network models. In addition, the experiments show that combination of GRU with CNN is better than that combination of CNN and GRU, and the combination of CNN with GRU performs better than employ CNN model alone. The accuracy of using single CNN is successively higher than that of LSTM, BI-GRU and GRU model. Our model which the combination of the BI-GRU, Attention and Capsule network introduced in this paper achieves the highest accuracy, precision and F1 score. In conclusion, the bidirectional GRU with self-attention mechanism and capsule network model significantly improves the accuracy of text sentiment classification task.

Finance contributes to poverty alleviation through economic growth, and the development of green finance is related to the sustainable development of the world economy and environment. Green finance not only helps promote sustainable economic development but also helps reduce poverty. Based on the analysis of related theories about green finance and poverty alleviation, this paper selects 18 indicators from three dimensions of economic development, financial development, and social environmental development and uses the improved entropy method to measure the green finance development index of China’s 25 provinces and municipalities from 2004 to 2017. The results show that the development level of green finance in China’s 25 provinces and municipalities is quite different. On the basis of the above analysis, make an empirical analysis of the impact of the green finance development index on poverty alleviation using multiple regression analysis and static panel and dynamic panel estimation methods. The research results show that there is a significant positive correlation between green finance and poverty alleviation; the higher the level of green finance development, the more conducive the poverty alleviation. So, this paper suggests that poverty can be better alleviated by improving the level of green finance development, financial asset level, and economic development level.

Photocatalytic reduction of hexavalent chromium [Cr(VI)] is a promising technology approach to highly efficiently and environmentally tackle the problem of Cr(VI) pollution, in which the key challenge is in the development of effective photocatalysts. In this work, highly reduced hourglass-type molybdophosphate hybrids with the formulas [Zn(mbpy)(H

Based on the calculation of the inclusive financial development level of 22 provinces and 4 municipalities in China from 2004 to 2017, this paper uses the Kernel density estimation method to further analyze the evolution of the inclusive financial index. Based on the above analysis, we make empirical analysis of the impact of China's inclusive financial inclusion development index on farmers' entrepreneurship using static panel and dynamic panel estimation method. The empirical conclusions show that there are certain differences in inclusive financial inclusion development level in various provinces in China. Improving the inclusion development level of inclusive finance can better promote farmers' entrepreneurship. Urbanization level, economic openness and regional economic development level have a significant positive effect on farmers' entrepreneurship, while farmers' income and education level have a significant negative effect on farmers' entrepreneurship. It is possible to promote farmers' entrepreneurship by improving the inclusive development level of inclusive finance, combining urbanization, increasing government investment in productive fixed assets, increasing economic openness and improving regional economic development.

Forsythenethoside A (1) is a structurally unique macrocyclic phenylethanoid glycoside, which was isolated from Forsynthia suspensa and displayed considerable neuroprotective activities. Here, we report its first chemical synthesis via a longest linear sequence of 14 steps in 5% overall yield wherein intramolecular oxidative coupling was successfully employed to realize the pivotal macrocyclization. NMR analysis revealed the existence of an unexpected conformational interconversion of the congested macrocycles.

Four new analogues of brefeldin A named 7, 7-dimethoxybrefeldin C (3), 6β-hydroxybrefeldin C (4), 4-epi-15-epi-brefeldin A (5), 4-epi-8α-hydroxy-15-epi-brefeldin C (6), together with four known analogues (1, 7-9) were isolated from a fermentation of the sediment-derived fungus Penicillium sp. DT-F29. The structures of these compounds were elucidated on the basis of extensive spectroscopic and chemical methods. In the bioactivity assays, only compounds 1 and 8 showed significant inhibitory activities against human lung adenocarcinoma cell. In addition, compound 1 was first reported for the potent ability to reactivate latent HIV with EC50 value of 0.03 μM.

The scattering model of incident seismic waves by an empty borehole has been presented to investigate the theoretical frequency response and the corresponding bandwidth of borehole tensor strainmeters. Inner-diameter changes of the stainless steel instrument casing are measured by horizontal extensometers (gauges), after the borehole tensor strainmeter is installed at a certain depth of the borehole and boned by expansive grout with the surrounding rock. There is, however, no answer for the difference between this case and the empty case. In this paper, the scattering model of incident elastic seismic waves by a two-ring borehole is introduced to investigate the influence of the expansive grout on theoretical bandwidth for the measurement of strain waves by borehole tensor strainmeters. The calculation of wave fields in the surrounding rock and the two rings by wave function expansion gives the inner-diameter changes of the stainless steel instrument casing. Several cases show that the mechanical parameters of the expansive grout have great influence on the frequency responses of borehole tensor strainmeters for different gauge combinations, but little influence on the bandwidth, which means that the high-frequency bandwidth promises the quantitative measurability of strain waves in the acoustical frequency range for borehole tensor strainmeters.

Glycoproteomics is greatly developed in recent years and big data of N-glycoproteome in mammalian tissues and cells were already established. However, the glycoproteomic studies on plant, fungus and bacteria are far left behind. In this study, we comprehensively mapped and quantified the N-glycosylation of Fusarium graminearum by combining stable isotope dimethyl labeling, hydrophilic interaction chromatography (HILIC) and high-resolution mass spectrometry. The N-glycosylation changes in Fusarium graminearum after fungicide treatment were extensively studied. Altogether we identified 927 N-glycopeptides, corresponding to 406 proteins and 774 sites and the glycosylation level was found to be largely down-regulated upon fungicide treatment. With the help of advanced bioinformatics, it was found that the N-glycoproteome changes were highly enriched in cell wall, membrane and extracellular regions. Moreover, the fungal metabolism, protein and glycosylation synthesis, and protease and glycosyl-transferase activity were all closely related with the down-regulated proteins, indicates that fungicide may affect fungal development in these aspects. These results will be useful for future studies on fungal biology. The established system for N-glycoproteome quantification has comparative or better performance compared with previous strategies and will be helpful in N-glycoproteomics of fungus and other species. Significance We developed a robust HILIC-based system for N-glycoproteome quantification in fungus and established the largest quantitative N-glycosylation dataset in fungus, showing the high performance of the new system. The identified N-glycoproteins were proved to be high confident due to the high percentage of proteins in extracellular region and plasma. The quantification results were also accuracy and reproducible in two replicates. By the help of advanced bioinformatic tools, the obtained data was systematically analyzed. It was found that the N-glycosylation level was largely changed in cell wall, membrane and extracellular regions. Moreover, the cell metabolism, protein synthesis, and protease activity were also greatly deceased after fungicide treatment.

The purpose of this study was to quantify the potential level of protection that secondary disinfection may provide in response to an intrusion event. Although several uncertainties exist regarding intrusion events, this study presents an analysis of the inactivation provided by disinfectant residuals by using a distribution system model, inactivation and disinfectant decay models, and conservative assumptions based on available data. A variety of conditions were modeled, including a range of water quality parameters (pH, temperature); inactivation of two microorganisms, Giardia and E. coli O157:H7; and intrusion water dilution ratios. Despite the assumptions inherent in the model, several generalizations were derived from the study. A free chlorine residual of 0.5 mg∕L may be insufficient to provide adequate control of disinfectant-resistant Giardia even at low pH (6.5) and high temperature (25°C) conditions that enhance chlorine effectiveness. For E. coli, an organism of “average” disinfectant resistanc...

Competitive coexistence of different microorganism species is a fundamental ecological process in the evolution and maintenance of biodiversity. This work studied the interactions happened in the competitive coexistence process of actinomycete Streptomyces sp. and Escherichia coli from morphological and secondary metabolites perspective. We found three important interactions occurred in their successful coexistence process: medium pH was elevated, indole alkaloids with dual inhibiting effects were produced, and culture environment was spatially structured. For the weed-like superior competitor E. coli, its massive growth was suppressed by the elevated pH and the newly produced novel bisindole alkaloid hepchrome. For the inferior Streptomyces sp., its mycelium floated to the medium surface for further colonization, and the growth in liquid medium was inhibited by its self-produced alkaloids such as halichrome A, 1,1,1-Tris (3-indolyl) methane, vibrindole A, and hepchrome. The coexistence of E. coli and Streptomyces sp. was thereby achieved through reduction of spatial and energy resource overlapping and suppression of competition.

Tryptamine derivatives such as tryptamine and bacillamides were strong algicidal compounds promising in controlling harmful algae blooms, but their bioactivity and application researches were hindered by extremely low natural production rates. This study found an induced production of algicidal tryptamine derivatives by co-culture of marine Streptomyces with Bacillus mycoides, and optimised the culture method through changing important factors such as medium nutrition content, culture mode and pH value. The final established co-culture method used only 5 g yeast extracts and 5 g glycerol in 1 L 75% sea water, but got a yield of 14.9 mg/L N-acetyltryptamine, 2.8 mg/L N-propanoyltryptamine, 3.0 mg/L bacillamide A, 13.7 mg/L bacillamide B and 9.6 mg/L bacillamide C, which were all undetectable under normal culture conditions.

The main objective of this paper was to evaluate the effectiveness of silica sand, crushed glass, peat, and geotextile as a medium in RBFs in the removal for organic matter, nutrients and bacteria from domestic wastewater based on a field-scale study. In particular, this field-scale study was conducted to treat domestic wastewater from a small community of 10 households from the Municipality of Lunenburg, Nova Scotia, Canada. The average influent 5d biochemical oxygen demand (BOD(5)) and total suspended solids (TSS) concentrations into the field filter system were 381+/-64 (mean+/-standard deviation) and 46+/-21 mg/L, respectively. The results showed that crushed glass could be an effective medium in RBFs since the crushed glass filter produced stable effluent BOD(5) and TSS concentrations of less than 20mg/L. Geotextile was found to be another successful alternative filter medium with the effluent BOD(5) and TSS of 18+/-11 and 11+/-7 mg/L, respectively, even though the porosity of geotexitle filter was as high as 0.90. Peat was not able to provide efficient performance due to its poor BOD(5) and NH(4)(+)-N removals. This study measured the water quality variation at different components of the RBFs. The results of this study showed that the recirculation tank was the main facilitator of the denitrification process. In addition, this study found that RBFs could efficiently treat domestic wastewater for BOD(5) removal under the organic loading rates as high as 0.070 kg/m(2)/d.