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为探索高含量中长链脂肪酸甘油三酯（MLCT）和低成本的酶法催化合成MLCT工艺，以一级菜籽油为原料，采用脂肪酶Lipozyme TL IM酶法催化酯交换合成MLCT，采用单因素试验研究了底物配比（菜籽油与中链甘油三酯质量比）、反应时间、反应温度、酶添加量对酯交换反应的影响，在此基础上，通过正交试验对MLCT合成工艺条件进行优化。结果表明，最佳的MLCT合成工艺条件为底物配比 3∶ 1、反应时间4 h、反应温度50℃、酶添加量8%（基于底物的质量），在此条件下MLCT含量达到87.50%。优化的MLCT合成工艺具有MLCT含量高，反应时间短、反应温度低的优势，可降低能耗及减少酶失活，从而降低了生产成本。 To explore the enzymatic catalytic synthesis process of medium long-chain fatty acid triglyceride (MLCT)with high MLCT content and low cost, lipase Lipozyme TL IM enzymatic catalytic transesterification was used to synthesize MLCT using first-grade rapeseed oil as raw material, and the effects of substrate ratio(mass ratio of rapeseed oil to medium chain triglycerides), reaction time, reaction temperature and enzyme dosage on transesterification reaction were investigated by single factor experiment. Then the synthesis process conditions were optimized by orthogonal experiment. The results showed that the optimal synthesis process conditions were obtained as follows: substrate ratio 3∶ 1, reaction time 4 h, reaction temperature 50℃, and enzyme dosage 8%(based on the mass of substrate), and the MLCT content reached 87.50% under the optimal conditions. The optimized process has advantages of high MLCT content, short reaction time and low reaction temperature, which can reduce energy consumption and enzyme inactivation, thus reducing the production cost.

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Copyright of Modern Preventive Medicine is the property of Modern Preventive Medicine Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Modern Preventive Medicine is the property of Modern Preventive Medicine Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Feed Research is the property of Editorial Board of Feed Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With rapid urbanization and the structural transformation of economic development, cultivated land abandonment is becoming more serious, posing great threats and challenges to the security of food production. The rapid and accurate monitoring of cultivated land abandonment is of great value for ensuring regional and national food security. In view of the urgent need for abandoned land monitoring, we proposed a method to identify abandoned land based on the temporal features of optical time series data. First, the NDVI time series of cultivated lands was constructed using multitemporal Sentinel-2 data. The constructed NDVI time series was preprocessed to filter out outliers among the observations. Subsequently, the amplitude feature of the NDVI time series was extracted for cultivated land. We acquired the amplitudes of the abandoned and non-abandoned land samples and generated statistics for the range of amplitudes. We then extracted the optimal threshold of NDVI amplitude for separating abandoned land from non-abandoned land using two steps: initialization and optimization of the threshold. In the initialization step, the maximum NDVI amplitude among the abandoned land samples was set as the initial threshold. In the optimization step, the threshold was decreased in step of 0.01, and the F1-score was calculated iteratively to determine the optimal threshold. With a decrease in the threshold when the F1-score reached its highest value, the corresponding threshold was set as the optimal threshold. Accordingly, the rule for abandoned land recognition was constructed; namely, when the NDVI amplitude was lower than the optimal threshold, cultivated land was classified as abandoned land. Finally, based on the mapping results, landscape pattern indices were calculated to analyze the landscape pattern characteristics of abandoned lands. The proposed method was validated in Potou District, Zhanjiang City, Guangdong Province, China. The main results of the study were as follows: 1) Comparing the NDVI time series curves of abandoned and non-abandoned lands, we found that the NDVI time series curves of abandoned land changed gently, whereas the NDVI time series of non-abandoned land changed with great fluctuation due to the phenological process of crop growth. 2) By iteratively searching for the optimal NDVI amplitude, the optimal segmentation threshold of NDVI amplitude was 0.42 for distinguishing abandoned lands from non-abandoned lands in Potou. We used 100 abandoned and non-abandoned land samples to validate their accuracy. By using this optimal threshold, the overall recognition accuracy of abandoned land reached 91.83%, and the overall extraction accuracy of non-abandoned land reached 90.20%. 3) The calculation results of the landscape pattern index of abandoned lands revealed that these are generally small and have irregular shapes. Abandoned lands were scattered throughout Potou. This study demonstrates that the proposed method can effectively identify abandoned land using the amplitude of NDVI time series. This method can produce highly reliable abandoned land mapping and shows good potential for largescale agricultural applications. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Application Research of Computers / Jisuanji Yingyong Yanjiu is the property of Application Research of Computers Edition and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Objective: Lactic acid accumulation is one of the main causes of acidic tumor microenvironment （TME）, and macrophages are important cells in TME. In this study, we screened the key target molecules in the regulation of M2-type polarization of mouse peritoneal macrophages by lactic acid, and provided theoretical basis for macrophage-related tumor immunotherapy. Methods: Peritoneal macrophages were extracted from mice and the expression levels of F4/80+ and CD11b+ cells were detected by flow cytometry. Macrophages were divided into 2 groups, and treated with 0 mmol/L（control） and 20 mmol/L lactic acid medium for 24 h, respectively. The cells were collected, and the relative expression levels of IL-10, Arg-1, VEGF, HIF-1 and other genes in macrophages were detected by qPCR. Transcriptome sequencing technology was used to screen the differentially expressed genes （|log2（fold change）|>1） in the control group and the 20 mmol/L lactic acid group. GO and KEGG analysis were performed on the differentially expressed genes, and Cytoscape software was used to construct the interaction network diagram of the differentially expressed genes. Key regulatory genes such as Tpt1 and Malat1 were screened according to the number of gene interaction nodes. siRNA of two key genes Tpt1 and Malat1 were transfected into macrophages respectively to inhibit the expressions of the two genes. The relative expression levels of CD11c, Arg-1 and VEGF genes in the transfected macrophages were detected by qPCR method. Results: The expression levels of F4/80+ and CD11b+ cells in mouse peritoneal cells were both greater than 90%, indicating that we have successfully obtained high-purity mouse peritoneal macrophages. Compared with control group, the expression levels of Arg-1, HIF-1, IL-10 and VEGF increased after 20 mmol/L lactic acid treatment, suggesting that lactic acid can promote M2-type polarization of macrophages. Transcriptome study showed that 6 295 genes in macrophages were changed after 20 mmol/L lactic acid treatment for 24 h, and the differentially expressed genes were mainly involved in bacterial defense response, cytoplasmic gene translation, ribosomal biosynthesis, placental development and other biological processes. The involved signaling pathways include MAPK, PI3K-Akt, NOD-like receptor, etc. Key up-regulated differentially expressed genes, such as Malat1, Tpt1, Fadd, Gm5900 and Gipr, were screened. After Malat1 or Tpt1 expressions were inhibited, 20 mmol/L lactic acid could up-regulate the expression of CD11c in macrophages and inhibit the expressions of VEGF and Arg-1. Conclusion: Lactic acid may promote M2-type polarization of macrophages by up-regulating Malat1 and Tpt1 expressions. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Chinese Journal of Clinical Healthcare is the property of Chinese Journal of Clinical Healthcare and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of International & Comparative Education is the property of International & Comparative Education Editorial, Beijing Normal University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Chongqing University of Technology (Natural Science) is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Progress in Modern Biomedicine is the property of Publishing House of Progress in Modern Biomedicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Heart rate variability is composed of changes in continuous heartbeat interval. The oscillation of a healthy heart is complex and constantly changing, which enables the cardiovascular system to adjust rapidly to cope with sudden physical and psychological challenges, so as to maintain internal balance. At present, acute coronary syndrome is still a critical and severe cardiovascular disease in China, and how to evaluate its severity and predict poor prognosis is still a research hotspot. The article reviews the application of heart rate variability in acute coronary syndrome. [ABSTRACT FROM AUTHOR]

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Copyright of Science & Technology of Cereals, Oils & Foods is the property of Science & Technology of Cereals, Oils & Foods Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Clinical Nursing in Practice is the property of Journal of Clinical Nursing in Practice (Editorial Board, Shanghai Jiao Tong University Press) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Tropical Medicine is the property of China Tropical Medicine Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective To investigate the rules of Traditional Chinese Medicine in the treatment of perimenopausal syndrome (PMS) and provide a theoretical basis for the clinical treatment of PMS. Methods The literature related to PMS were collected from China Knowledge Network (CNKI), Wanfang database and Weipu database in the past 20 years, the herbal compound prescriptions for the treatment of PMS were screened and a relevant database were established and analyzed by SPSS. Results The relevant literatures contains 184 Chinese medicine prescriptions/proprietary Chinese medicines, 122 flavors of traditional Chinese medicines, and the drug categories were mainly tonic drugs, antipyretic drugs, astringent drugs, and tranquilizers. The core single-flavor Chinese medicines were Baishao(Radix Paeoniae Alba), Shudihuang(Rehmannia glutinosa ), Danggui(Radix Angelicae Sinensis), Fuling (Indian Buead). The property and flavor covered sweet, bitter, cold, etc.; and the channel tropism belonged to the liver, kidneys, heart, lungs, spleen and meridians. The cluster analysis of high-frequency Traditional Chinese Medicine obtained two main combinations. Conclusion TCM treatment of PMS focused on replenishing qi, soothing the liver, nourishing the kidneys, nourishing blood and calming the heart, and then according to clinical compatibility with drugs such as soothing the nerves, clearing heat and removing dampness; most of its clinical treatment were Xiaoyaosan, Liuwei Dihuang pills, and Zhibo Rehmanniae decoction and other prescriptions which were added and subtracted. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Cereals, Oils & Foods is the property of Science & Technology of Cereals, Oils & Foods Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)