This study aims at the development of magnetically recyclable solid catalysts for the production of biodiesel. To achieve this, the magnetically susceptible Fe3O4/MCM-41 composites with core-shell ...structure were prepared, and sodium silicate was then supported on the magnetic materials by using epichlorohydrin as a cross-linking reagent. The core-shell structured magnetic support and so-prepared solid catalyst were characterized by various techniques. Characterization results showed that the sodium silicate was chemically bridged onto the Fe3O4/MCM-41 composites without obvious damage to the structure of the magnetic support. The solid catalyst exhibited a strong magnetic response and displayed extraordinary catalytic activities in the transesterification of soybean oil for the production of biodiesel, with the oil conversion reaching 99.2% by using the methanol-to-oil molar ratio of 25:1 and catalyst loading of 3 wt% at reflux of methanol after 8 h of reaction. Moreover, the separation of the solid catalyst from reaction mixture was readily achieved by simple magnetic decantation without obvious mass loss, and the solid catalyst could be reused for five times for the heterogeneous transesterification.
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•Magnetic solid catalysts were used for biodiesel production in a heterogeneous manner.•The catalyst could give the soybean oil conversion of 99.2%.•The solid catalyst had a long-term catalytic activity.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The green development of free trade zones conforms to the theoretical principles of sustainable development and is key to promoting regional transformation and upgrading. By using synthetic control ...methods (SCM) based on microscopic data, this paper investigates the net effect of the establishment of the China (Shanghai) pilot free trade zone (SPFTZ) on green total factor productivity (GTFP) in Shanghai. The results show that the SPFTZ has promoted the GTFP in Shanghai. As far as time trend is concerned, the effects of this promotion become more apparent after a short-term period of slow growth. In terms of impact paths, the main driving force of policy is technological progress. Therefore, the SPFTZ should improve GTFP and create greater incentives for technological innovation. Institutional innovation for green development should play a central guiding role in the construction. We need continue to explore other green development models as well as means of creating higher levels of economic openness.
•Introduce energy input and undesirable output into the economic efficiency model.•The SPFTZ has promoted the growth of Shanghai GTFP.•The green policy effect of SPFTZ shows substantial enhancement after slow growth.•The promotion effect stemmed from the improvement of technological progress.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
As an important medium of intercellular communication, exosomes play an important role in information transmission between tumor cells and their microenvironment. Tumor metastasis is a serious ...influencing factor for poor treatment effect and shortened survival. Lung cancer is a major malignant tumor that seriously threatens human health. The study of the underlying mechanisms of exosomes in tumor genesis and development may provide new ideas for early and effective diagnosis and treatment of lung cancer metastasis. Many studies have shown that tumor-derived exosomes promote lung cancer development through a number of processes. By promoting epithelial-mesenchymal transition of tumor cells, they induce angiogenesis, establishment of the pretransfer microenvironment, and immune escape. This understanding enables researchers to better understand the mechanism of lung cancer metastasis and explore new treatments for clinical application. In this article, we systematically review current research progress of tumor-derived exosomes in metastasis of lung cancer. Although positive progress has been made toward understanding the mechanism of exosomes in lung cancer metastasis, systematic basic research and clinical translational research remains lacking and are needed to translate our scientific understanding toward applications in the clinical diagnosis and treatment of lung cancer metastasis in the near future.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This paper presents the concept and algorithm of data mining and focuses on the linear regression algorithm. Based on the multiple linear regression algorithm, many factors affecting CET4 are ...analyzed. Ideas based on data mining, collecting history data and appropriate to transform, using statistical analysis techniques to the many factors influencing the CET-4 test were analyzed, and we have obtained the CET-4 test result and its influencing factors. It was found that the linear regression relationship between the degrees of fit was relatively high. We further improve the algorithm and establish a partition-weighted K-nearest neighbor algorithm. The K-weighted K nearest neighbor algorithm and the partition algorithm are used in the CET-4 test score classification prediction, and the statistical method is used to study the relevant factors that affect the CET-4 test score, and screen classification is performed to predict when the comparison verification will pass. The weight K of the input feature and the adjacent feature are weighted, although the allocation algorithm of the adjacent classification effect has not been significantly improved, but the stability classification is better than K-nearest neighbor algorithm, its classification efficiency is greatly improved, classification time is greatly reduced, and classification efficiency is increased by 119%. In order to detect potential risk graduating students earlier, this paper proposes an appropriate and timely early warning and preschool K-nearest neighbor algorithm classification model. Taking test scores or make-up exams and re-learning as input features, the classification model can effectively predict ordinary students who have not graduated.
Abiotic stresses adversely affect plant growth and agricultural productivity. According to the current climate prediction models, crop plants will face a greater number of environmental stresses, ...which are likely to occur simultaneously in the future. So it is very urgent to breed broad-spectrum tolerant crops in order to meet an increasing demand for food productivity due to global population increase. As one of the largest families of transcription factors (TFs) in plants, NAC TFs play vital roles in regulating plant growth and development processes including abiotic stress responses. Lots of studies indicated that many stress-responsive NAC TFs had been used to improve stress tolerance in crop plants by genetic engineering. In this review, the recent progress in NAC TFs was summarized, and the potential utilization of NAC TFs in breeding abiotic stress tolerant transgenic crops was also be discussed. In view of the complexity of field conditions and the specificity in multiple stress responses, we suggest that the NAC TFs commonly induced by multiple stresses should be promising candidates to produce plants with enhanced multiple stress tolerance. Furthermore, the field evaluation of transgenic crops harboring NAC genes, as well as the suitable promoters for minimizing the negative effects caused by over-expressing some NAC genes, should be considered.
The Lungmachi Formation is widely distributed in Guizhou, Chongqing and the adjacent area. It is important for the study of Silurian biostratigraphy and shale-gas investigation. Based on those ...biostratigraphically well-studied sections from Guiyang to Huayingshan, we reveal the stage-progressive distribution pattern of the Lungmachi black shales. The distribution of the Lungmachi black shales in the studying area can be subdivided into four geographic belts from the south to the north,reflecting the joint effect of regional and global environmental changes. The graptolite depth zonation model was adopted herein to infer the water depth of major graptolite assemblages from the black shales. The changes in the water depth indicate two major stages. The first stage is named the transgressive distribution stage which ranged from the Persculptograptus persculptus Biozone（LM1, upper Hirnantian） to the Coronograptus cyphus Biozone（LM5, upper Rhuddanian）, an interval mostly controlled by global sea-level rise. The second stage, ranging from the Demirastrites triangulatus Biozone（LM6, lower Aeronian） to the Spirograptus guerichi Biozone（LM9, lower Telychian）, is named the regressive shrinking stage, during which the black shales were gradually replaced by mixed-facies or carbonate sediments from the south to the north, representing the effects of the persistent uplifting of the Central Guizhou Oldland.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Dementia, a condition that frequently afflicts patients in advanced stages of Parkinson's disease (PD), results in decreased quality of life and survival time. Nevertheless, the pathological ...mechanisms underlying Parkinson's disease dementia (PDD) are not completely understood. The symptoms characteristic of PDD may be the result of functional and structural deficiencies. The present study implicates the accumulation of Lewy bodies in the cortex and limbic system as a potent trigger in the development of PDD. In addition, significant Alzheimer-type pathologies, including amyloid-β (Aβ) plaques and NFTs, are observed in almost half of PDD patients. Interestingly, links between PDD pathogenesis and the mechanisms underlying the development of insulin resistance have begun to emerge. Furthermore, previous studies have demonstrated that insulin treatment reduces amyloid plaques in Alzheimer's disease (AD), and normalizes the production and functionality of dopamine and ameliorates motor impairments in 6-OHDA-induced rat PD models. GSK3β, a downstream substrate of PI3K/Akt signaling following induction by insulin and IGF-1, exerts an influence on AD and PD physiopathology. The genetic overexpression of GSK3β in cortex and hippocampus results in signs of neurodegeneration and spatial learning deficits in
models (Lucas et al., 2001), whereas its inhibition results in improvements in cognitive impairment in these rodents, including AD and PD. Accordingly, insulin- or IGF-1-activated PI3K/Akt/GSK3β signaling may be involved in PDD pathogenesis, at least in the pathology of PD-type + AD-type.
Black rot, Black measles, Leaf blight and Mites of grape are four common grape leaf diseases that seriously affect grape yield. However, the existing research lacks a real-time detecting method for ...grape leaf diseases, which cannot guarantee the healthy growth of grape plants. In this article, a real-time detector for grape leaf diseases based on improved deep convolutional neural networks is proposed. This article first expands the grape leaf disease images through digital image processing technology, constructing the grape leaf disease dataset (GLDD). Based on GLDD and the Faster R-CNN detection algorithm, a deep-learning-based Faster DR-IACNN model with higher feature extraction capability is presented for detecting grape leaf diseases by introducing the Inception-v1 module, Inception-ResNet-v2 module and SE-blocks. The experimental results show that the detection model Faster DR-IACNN achieves a precision of 81.1% mAP on GLDD, and the detection speed reaches 15.01 FPS. This research indicates that the real-time detector Faster DR-IACNN based on deep learning provides a feasible solution for the diagnosis of grape leaf diseases and provides guidance for the detection of other plant diseases.
Highly specific Cas9 nucleases derived from SpCas9 are valuable tools for genome editing, but their wide applications are hampered by a lack of knowledge governing guide RNA (gRNA) activity. Here, we ...perform a genome-scale screen to measure gRNA activity for two highly specific SpCas9 variants (eSpCas9(1.1) and SpCas9-HF1) and wild-type SpCas9 (WT-SpCas9) in human cells, and obtain indel rates of over 50,000 gRNAs for each nuclease, covering ~20,000 genes. We evaluate the contribution of 1,031 features to gRNA activity and develope models for activity prediction. Our data reveals that a combination of RNN with important biological features outperforms other models for activity prediction. We further demonstrate that our model outperforms other popular gRNA design tools. Finally, we develop an online design tool DeepHF for the three Cas9 nucleases. The database, as well as the designer tool, is freely accessible via a web server, http://www.DeepHF.com/ .
The increasing seriousness of salinization aggravates the food, population and environmental issues. Ameliorating the salt-resistance of plants especially the crops is the most effective measure to ...solve the worldwide problem. The salinity can cause damage to plants mainly from two aspects: hyperosmotic and hyperionic stresses leading to the restrain of growth and photosynthesis. To the adverse effects, the plants derive corresponding strategies including: ion regulation and compartmentalization, biosynthesis of compatible solutes, induction of antioxidant enzymes and plant hormones. With the development of molecular biology, our understanding of the molecular and physiology knowledge is becoming clearness. The complex signal transduction underlying the salt resistance is being illuminated brighter and clearer. The SOS pathway is the central of the cell signaling in salt stress. The accumulation of the compatible solutes and the activation of the antioxidant system are the effective measures for plants to enhance the salt resistance. How to make full use of our understanding to improve the output of crops is a huge challenge for us, yet the application of the genetic engineering makes this possible. In this review, we will discuss the influence of the salt stress and the response of the plants in detail expecting to provide a particular account for the plant resistance in molecular, physiological and transgenic fields.
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BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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