An overview is presented for the formation and evolution of Precambrian continental lithosphere in South China. This is primarily based on an integrated study of zircon U–Pb ages and Lu–Hf isotopes ...in crustal rocks, with additional constraints from Re–Os isotopes in mantle-derived rocks. Available Re–Os isotope data on xenolith peridotites suggest that the oldest subcontinental lithospheric mantle beneath South China is primarily of Paleoproterozoic age. The zircon U–Pb ages and Lu–Hf isotope studies reveal growth and reworking of the juvenile crust at different ages. Both the Yangtze and Cathaysia terranes contain crustal materials of Archean U–Pb ages. Nevertheless, zircon U–Pb ages exhibit two peaks at 2.9–3.0Ga and ~2.5Ga in Yangtze but only one peak at ~2.5Ga in Cathaysia. Both massive rocks and crustal remnants (i.e., zircon) of Archean U–Pb ages occur in Yangtze, but only crustal remnants of Archean U–Pb ages occur in Cathaysia. Zircon U–Pb and Lu–Hf isotopes in the Kongling complex of Yangtze suggest the earliest episode of crustal growth in the Paleoarchean and two episodes of crustal reworking at 3.1–3.3Ga and 2.8–3.0Ga. Both negative and positive εHf(t) values are associated with Archean U–Pb ages of zircon in South China, indicating both the growth of juvenile crust and the reworking of ancient crust in the Archean. Paleoproterozoic rocks in Yangtze exhibit four groups of U–Pb ages at 2.1Ga, 1.9–2.0Ga, ~1.85Ga and ~1.7Ga, respectively. They are associated not only with reworking of the ancient Archean crust in the interior of Yangtze, but also with the growth of the contemporaneous juvenile crust in the periphery of Yangtze. In contrast, Paleoproterozoic rocks in Cathaysia were primarily derived from reworking of Archean crust at 1.8–1.9Ga. The exposure of Mesoproterozoic rocks are very limited in South China, but zircon Hf model ages suggest the growth of juvenile crust in this period due to island arc magmatism of the Grenvillian oceanic subduction. Magmatic rocks of middle Neoproterozoic U–Pb ages are widespread in South China, exhibiting two peaks at about 830–800Ma and 780–740Ma, respectively. Both negative and positive εHf(t) values are associated with the middle Neoproterozoic U–Pb ages of zircon, suggesting not only growth and reworking of the juvenile Mesoproterozoic crust but also reworking of the ancient Archean and Paleoproterozoic crust in the middle Neoproterozoic. The tectonic setting for this period of magmatism would be transformed from arc–continent collision to continental rifting with reference to the plate tectonic regime in South China.
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► Crustal growth and reworking are episodic from Eoarchean to Neoproterozoic in South China. ► The growth of juvenile crust is significant in the Archean, but no Archean SCLM is measured. ► Both growth and reworking of mantle and crustal lithospheres are prominent in the middle Paleoproterozoic. ► Both juvenile and ancient crusts underwent intensive reworking in the middle Neoproterozoic. ► The arc–continent collision is a tectonic mechanism for continental accretion in South China.
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•The combined effects of ultrasound intensity and protein concentration were revealed.•Low- and high-intensity ultrasound changed the particle size of proteins oppositely.•Ultrasound ...in a crowded environment improved the functionality of peanut proteins.
Peanut protein isolate (PPI) nanoparticles were prepared by self-assembly under the combined action of ultrasound (US) and protein concentration. The effects of ultrasound intensity (150–500 W) and protein concentration (1–12 %, w/v) on the structural and functional properties of PPI nanoparticles were investigated. Low-intensity US significantly increased the particle size of PPI, but high-intensity US decreased it. The largest PPI nanoparticles were obtained when 10 % PPI was subjected to low-intensity US treatment (200 W for 5 min). These nanoparticles possessed unique structural characteristics, such as the lowest absolute ζ-potential and the highest contents of exposed free sulfhydryl and disulfide bond, which may be responsible for their excellent heat-set gelling properties. The 12 % PPI treated with low- and high-intensity US had the highest emulsifying activity index and emulsifying stability index, respectively. The self-assembled PPI nanoparticles induced by US treatments at high protein concentrations have great potentials for application in the food industry.
Many protein‐coding oncofetal genes are highly expressed in murine and human fetal liver and silenced in adult liver. The protein products of these hepatic oncofetal genes have been used as clinical ...markers for the recurrence of hepatocellular carcinoma (HCC) and as therapeutic targets for HCC. Herein we examined the expression profiles of long noncoding RNAs (lncRNAs) found in fetal and adult liver in mice. Many fetal hepatic lncRNAs were identified; one of these, lncRNA‐mPvt1, is an oncofetal RNA that was found to promote cell proliferation, cell cycling, and the expression of stem cell‐like properties of murine cells. Interestingly, we found that human lncRNA‐hPVT1 was up‐regulated in HCC tissues and that patients with higher lncRNA‐hPVT1 expression had a poor clinical prognosis. The protumorigenic effects of lncRNA‐hPVT1 on cell proliferation, cell cycling, and stem cell‐like properties of HCC cells were confirmed both in vitro and in vivo by gain‐of‐function and loss‐of‐function experiments. Moreover, mRNA expression profile data showed that lncRNA‐hPVT1 up‐regulated a series of cell cycle genes in SMMC‐7721 cells. By RNA pulldown and mass spectrum experiments, we identified NOP2 as an RNA‐binding protein that binds to lncRNA‐hPVT1. We confirmed that lncRNA‐hPVT1 up‐regulated NOP2 by enhancing the stability of NOP2 proteins and that lncRNA‐hPVT1 function depends on the presence of NOP2. Conclusion: Our study demonstrates that the expression of many lncRNAs is up‐regulated in early liver development and that the fetal liver can be used to search for new diagnostic markers for HCC. LncRNA‐hPVT1 promotes cell proliferation, cell cycling, and the acquisition of stem cell‐like properties in HCC cells by stabilizing NOP2 protein. Regulation of the lncRNA‐hPVT1/NOP2 pathway may have beneficial effects on the treatment of HCC. (Hepatology 2014;60:1278–1290)
•A method for preparation of peanut antithrombotic peptides is developed.•The purified peptides show slightly lower antithrombotic activities than heparin.•Three new peanut antithrombotic peptide ...sequences are identified.
The antithrombotic activities of peanut protein hydrolysates were investigated using a microplates assay. When peanut proteins were hydrolyzed to a limited extent by various enzymes, their thrombin inhibitory abilities were significantly enhanced. However, the resultant hydrolysates showed significantly different activities even at the same degrees of hydrolysis. The hydrolysates generated by Alcalase 2.4L displayed the best antithrombotic activities and the hydrolysis process was further optimized by response surface methodology. The antithrombotic activities were increased to 86% based on a protein concentration of 50mg/ml under the optimal conditions: pH 8.5, enzyme concentration of 5000IU/g of peanut proteins, and 2h hydrolysis time at 50°C. The Alcalase 2.4L crude hydrolysates were then fractionated successively by preparative and semi-preparative reverse-phase high-performance liquid chromatography (RP-HPLC). The peptide fraction collected inhibited thrombin-catalyzed coagulation of fibrinogen completely at a concentration of 0.4mg/ml, with an antithrombotic activity close to that of heparin at quite a low concentration (0.2mg/ml). This peptide fraction was further analyzed by online reverse-phase ultra-performance liquid chromatography (RP-UPLC) coupled to matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), and three new peptides were identified as Ser-Trp-Ala-Gln-Leu, Gly-Asn-His-Glu-Ala-Gly-Glu and Cys-Phe-Asn-Glu-Tyr-Glu, respectively. This research provided an effective way to produce antithrombotic peptides from peanut proteins, and also helped to elucidate the structure–function relationships of peanut peptides.
In 1996, a mega project that aimed to develop rice varieties with super-high yield potential (super rice) was launched by the Ministry of Agriculture (MOA) in China using a combination of the ...ideotype approach and intersubspecific heterosis. Significant progress has been made in the last two decades, with a large number of super rice varieties being approved by the MOA and the national average grain yield being increased from 6.21 t ha?1 in 1996 to 6.89 t ha?1 in 2015. The increase in yield potential of super rice was mainly due to the larger sink size which resulted from larger panicles. Moreover, high-er photosynthetic capacity and improved root physiological traits before heading contributed to the increase in sink size. However, the poor grain filling of the later-flowering inferior spikelets and the quickly decreased root activity of super rice during grain filling period restrict the achievement of high yield potential of super rice. Furthermore, it is widely accepted that the high yield potential of super rice requires a large amount of N fertilizer input, which has resulted in an increase in N consumption and a decrease in nitrogen use efficiency (NUE), although it remains unclear whether super rice per se is responsible for the latter. In the present paper, we review the history and success of China's Super Rice Breeding Pro-gram, summarize the advances in agronomic and physiological mechanisms underlying the high yield potential of super rice, and examine NUE differences between super rice and ordinary rice varieties. We also provide a brief introduction to the Green Super Rice Project, which aims to diversify breeding targets beyond yield improvement alone to address global concerns around resource use and environmental change. It is hoped that this review will facilitate further improvement of rice production into the future.
We propose an underwater image enhancement model inspired by the morphology and function of the teleost fish retina. We aim to solve the problems of underwater image degradation raised by the ...blurring and nonuniform color biasing. In particular, the feedback from color-sensitive horizontal cells to cones and a red channel compensation are used to correct the nonuniform color bias. The center-surround opponent mechanism of the bipolar cells and the feedback from amacrine cells to interplexiform cells then to horizontal cells serve to enhance the edges and contrasts of the output image. The ganglion cells with color-opponent mechanism are used for color enhancement and color correction. Finally, we adopt a luminance-based fusion strategy to reconstruct the enhanced image from the outputs of ON and OFF pathways of fish retina. Our model utilizes the global statistics (i.e., image contrast) to automatically guide the design of each low-level filter, which realizes the self-adaption of the main parameters. Extensive qualitative and quantitative evaluations on various underwater scenes validate the competitive performance of our technique. Our model also significantly improves the accuracy of transmission map estimation and local feature point matching using the underwater image. Our method is a single image approach that does not require the specialized prior about the underwater condition or scene structure.
Lanxangia tsaoko’s accurate classifications of different origins and fruit shapes are significant for research in L. tsaoko difference between origin and species as well as for variety breeding, ...cultivation, and market management. In this work, Fourier transform‐near infrared (FT‐NIR) spectroscopy was transformed into two‐dimensional and three‐dimensional correlation spectroscopies to further investigate the spectral characteristics of L. tsaoko. Before building the classification model, the raw FT‐NIR spectra were preprocessed using multiplicative scatter correction and second derivative, whereas principal component analysis, successive projections algorithm, and competitive adaptive reweighted sampling were used for spectral feature variable extraction. Then combined with partial least squares‐discriminant analysis (PLS‐DA), support vector machine (SVM), decision tree, and residual network (ResNet) models for origin and fruit shape discriminated in L. tsaoko. The PLS‐DA and SVM models can achieve 100% classification in origin classification, but what is difficult to avoid is the complex process of model optimization. The ResNet image recognition model classifies the origin and shape of L. tsaoko with 100% accuracy, and without the need for complex preprocessing and feature extraction, the model facilitates the realization of fast, accurate, and efficient identification.
Asymmetric multi‐catalysis, designed to mimic catalytic processes in nature, is a powerful instrument to fulfil fascinating transformations. As a result, this area of research has attracted ...considerable interests within chemistry communities. Although there are numerous reviews involving multi‐catalysis, reviews describing asymmetric organomulticatalysis remain rare. Taking into consideration that organocatalysts possess the superiorities of effortless availability, inexpensiveness, hypotoxicity, facile handling and hyposensitivity to moisture and oxygen, they have definite advantage in their own distinct modes of activation when utilized in multi‐catalytic reactions. Organomulticatalysis refers to the synthetic strategies of modular combination of organo‐catalyzed reactions into one synthetic operation with minimum workup or change in conditions. It is apparent that a variety reports utilizing the concept of enantioselective organomulticatalysis have substantially surfaced in the past few years. Hence, it is indispensable to succinctly present all such reports by means of disclosing the mechanistic analysis, as well as the challenges and issues associated in the development of the asymmetric catalytic system. Additionally, this review will introduce some of the unsettled conundrums and possible innovations in this field.
In this paper, the attitude control of the quadrotor system under external disturbance is studied. A novel adaptive sliding mode control (ASMC) based on the linear extended state observer (LESO) is ...proposed, and the LESO is designed to estimate the lumped disturbance. An adaptive switching algorithm for changing the switching gain in real time is contained in the proposed ASMC. Then the disturbance estimation error can be compensated by the variable gain switching term in real time, therefore the robustness of the system can be further improved. The stability of the system is proved by Lyapunov theory. Finally, the simulation and experimental results verify the effectiveness of the control method.
Asymmetric hydrogenation of aromatic compounds represents one of the most straightforward synthetic methods to construct important chiral cyclic skeletons that are often found in biologically active ...agents and natural products. So far, the most successful examples in this field are largely limited to aromatics containing alkyl and aryl substituted groups due to the poor functional-group tolerance of hydrogenation. Direct asymmetric hydrogenation of functionalized aromatics provides enormous potential for expanding the structural diversity of reductive products of planar aromatic compounds, which is highly desirable and has not been well studied. This feature article focuses on the progress in catalytic asymmetric hydrogenation and transfer hydrogenation of O/N substituted arenes.
This feature article focuses on the progress in catalytic asymmetric hydrogenation and transfer hydrogenation of O/N substituted arenes.
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