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为减少甾醇酯的生产工序，提高大豆油脱臭馏分重相组分中总甾醇得率，采用柱层析法直接分离提取甾醇酯，通过单因素试验考察吸附剂种类、上样量、洗脱剂比例和柱长直比（填料高度与直径比）对甾醇酯产品纯度和得率的影响，确定最佳工艺条件，并对最佳工艺条件下分离提取的甾醇酯产品进行傅里叶红外光谱表征，以及甾醇组成和脂肪酸组成测定。结果表明，柱层析法分离提取甾醇酯的最佳工艺条件为吸附剂为硅胶（粒径50~75 μm），上样量0.5 g，洗脱剂比例为正己烷、乙醚、冰乙酸体积比95∶ 5∶ 1，柱长直比16∶ 1。在最佳工艺条件下，甾醇酯产品纯度为(89.90±0.94)%，得率为(9615±1.49)%；傅里叶红外光谱分析证实提取的产品中含甾醇酯，甾醇酯上的甾醇组成主要为β-谷甾醇、豆甾醇、菜油甾醇，脂肪酸组成主要为亚油酸、油酸、棕榈酸、硬脂酸和亚麻酸。综上，柱层析法无需复杂工序，即可实现大豆油脱臭馏分重相组分中甾醇酯的有效回收。In order to reduce the process of sterol ester production and increase the yield of total sterols in the waste residue of soybean oil deodorizer distillate (WRSODD), column chromatography was used to extract the sterol esters from WRSODD. The influence of absorbent type, sample loading amount, eluent ratio and ratio of column material height to diameter on the recovery rate and purity of sterol esters were examined by single factor experiment, and the optimum process conditions were selected. The sterol esters obtained under the optimum process conditions was analyzed by Fourier-infrared spectroscopy, and its sterols and fatty acid compositions were analyzed. The results showed that the optimum conditions were as follows: with silica gel powder (particle size 50-75 μm) as absorbent, sample loading amount 0.5 g, volume ratio of a mixture of n-hexane, diethyl ether and glacial acetic acid 95∶ 5∶ 1, and ratio of column material height to diameter 16∶ 1. Under these conditions, the purity and recovery rate of sterol esters were (89.90±0.94)% and (96.15±1.49)%, respectively. Fourier-infrared spectroscopy results verified that the product contained sterol esters. The sterol compositions of sterol esters were mainly β-sitosterol, stigmasterol and campesterol. The fatty acid compositions were palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid. In conclusion, effective recovery of sterol esters from the waste residue of soybean oil deodorizer distillate can be achieved through column chromatography without complex process.

Continuous application of fermented organic fertilizer can improve soil quality, while the performance of nitrogen (N) in the improved soils is rarely investigated. To investigate the fate of applied N in the soils with organic management history, the 15NH2CO15NH2 (15N abundance of 19.6 %) was employed as the exogenous N source to conduct an experiment in the Chinese cabbage and tomato rotation system under plastic shed condition. The cultivated soils have received 15-year of effective microorganism (EM) fermented organic fertilizer (EM-OF), N, P, K inorganic fertilizer (NPK-IF) and no fertilizer (NoF). The 15N use by cabbage and tomato, the soil 15N forms, as well as the 15N distribution were observed. Results showed that the 15N use efficiency of cabbage in the EM-OF, NPK-IF and NoF soils were 55.1 %, 37.3 % and 26.6 % respectively, showing significant (p ≤ 0.05) differences. The succeeding crop tomato could take up the soil residual 15N, and the highest 15N reuse efficiency was 7.1 % that detected in the NoF soil. The total 15N loss (6.0 %) from the rotation system was the lowest in the EM-OF soil, compared to that in the NPK-IF and NoF soils. It was concluded that the long-term fermented organic fertilizer applied soils can reduce urea 15N loss from plastic shed agriculture, mainly through improving the in-season crop 15N use efficiency.

Objective To evaluate the application effect of modified prehospital acute stroke severity scale（mPASS） in acute cerebral infarction due to large artery occlusion. Methods In this retrospective study, 112 patients with acute cerebral infarction were recruited and assigned into the occlusion （n = 59） and non-occlusion groups （n = 53） according to the presence of acute cerebral infarction due to large artery occlusion. The neurological functional scores at admission were collected： National Institutes of Health Stroke Scale （NIHSS）, PASS and mPASS scores. The Modified Rankin Scale （mRS） score was calculated to evaluate clinical prognosis. The predictive value of each score was expressed by the area under the receiver operating characteristic （ROC） curve （AUC）. The sensitivity and specificity were calculated. Youden index was utilized to assess the optimal cut-off value. The relationship between large artery occlusion and the sub-items of the mPASS was assessed by logistic regression analysis. Results The neurological functional and mRS scores in the occlusion group were significantly higher than those in the non-occlusion group （both P < 0.01）. The AUC, sensitivity, specificity, Youden index and accuracy of mPASS score were significantly higher compared with those of PASS score. Logistic regression analysis indicated that the cortical symptom-gaze yielded the most reference significance （P < 0.001）. The mRS score was positively correlated with the sub-items of mPASS （mRS score=0.554+0.037 consciousness level +1.965 gaze+0.206 limb movement+0.193 language function, F = 25.361, P < 0.001）. Conclusion Compared with NIHSS and PASS, mPASS is a more effective tool for identifying acute cerebral infarction due to large artery occlusion.

When optimizing irrigation methods, much consideration is given to crop growth indicators while less attention has been paid to soil's gaseous carbon (C) and nitrogen (N) emission indicators. Therefore, adopting an irrigation practice that can reduce emissions while maintaining crop yield and quality is of great interest. Thus, open-field experiments were conducted from September 2020 to January 2022 using a single-factor randomized block design with three replications. The lettuce plants ("Feiqiao Lettuce No.1") were grown using four different irrigation methods established by setting the lower limit of drip irrigation to 75%, 65%, and 55% of soil water content at field capacity corresponding to DR1, DR2, and DR3, respectively. Furrow irrigation (FI) was used as a control. Crop growth indicators and soil gas emissions were observed. Results showed that the mean lettuce yield under DR1 (64,500 kg/ha) was the highest, and it was lower under DR3 and FI. The lettuces under DR3 showed greater concentrations of crude fiber, vitamin C, and soluble sugar, and a greater nitrate concentration. Compared with FI, the DR treatments were more conducive to improving the comprehensive quality of lettuce, including the measured appearance and nutritional quality. Among all the irrigation methods, FI had the maximum cracking rate of lettuce, reaching 25.3%, 24.6%, and 22.7%, respectively, for the three continuous seasons. The stem cracking rates under DR2 were the lowest—only 10.1%, 14.4%, and 8.2%, respectively, which were decreased to nearly half compared with FI. The entropy model detected that the weight coefficient evaluation value of DR2 was the greatest, reaching 0.93, indicating that the DR2 method has the optimal benefits under comprehensive consideration of water saving, yield increase, quality improvement, and emission reduction. [ABSTRACT FROM AUTHOR]

Eleutherococcus senticosus (Rupr. & Maxim.) Maxim. fruits (ESF), as a natural edible fruit, has long been popularized. However, few studies have conducted comprehensive chemical analyses of it. This study aimed to assess nonvolatile, volatile, and fatty oil components of ESF and to preliminarily explore the antioxidant activities. The qualitative and quantitative analyses of volatile and fatty oil components of ESF from 15 different regions were performed by the gas chromatography–mass spectrometry (GC–MS). Totally, 37 and 28 compounds were identified from volatile oil and fatty oil, respectively. The ultra‐high‐performance liquid chromatography–quadrupole time‐of‐flight mass spectrometry (UPLC–QTOF–MS/MS) was used to accurately detect 43 compounds of nonvolatile components. The volatile and fatty oil components and nonvolatile components of ESF were used as samples to determine the antioxidant activity of 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) in vitro. The components of ESF had antioxidant activity, and the nonvolatile components had stronger antioxidant activity. The results revealed that the proposed method, which is of great significance for the screening of new active ingredients, is valuable for the identification of pharmaceutical component and further development of food industry. [ABSTRACT FROM AUTHOR]

Lettuce is a water-sensitive stem-used plant, and its rapid growth process causes significant disturbances to the soil. Few studies have focused on the gaseous carbon emissions from lettuce fields under different irrigation methods. Therefore, this study investigated the effect of different drip-irrigation lower limits and methods (drip and furrow irrigation) on greenhouse gas (CO2, CH4) emissions from lettuce fields. Thus, drip irrigation (DI) was implemented using three different lower limits of irrigation corresponding to 75%, 65%, and 55% of the field capacity, and named DR1, DR2, and DR3, respectively. Furrow irrigation (FI) was used as a control treatment. The CO2 and CH4 emission fluxes, soil temperature, and soil enzyme activities were detected. The results showed that the cumulative CO2 emission was highest under DR3 and relatively lower under DR1. For the FI treatment, the cumulative CO2 emission (382.7 g C m−2) was higher than that under DR1 but 20.2% lower than that under DR2. The cumulative CH4 emissions under FI (0.012 g C m−2) were the greatest in the whole lettuce growth period, while DR2 and DR3 treatments emitted lower amounts of CH4. The irrigation method considerably enhanced the activity of urease and catalase, meanwhile promoting CO2 emission. The low irrigation amount each time combined with high irrigation frequency reduced soil CO2 emission while increasing CH4 emission. From the perspective of the total reduction of gaseous carbon, DR1 is the optimal drip irrigation method among all the irrigation lower limits and methods. [ABSTRACT FROM AUTHOR]

Lipophilic antioxidants are used in edible oils and oleaginous foods. Therefore, development of novel lipophilic antioxidant is very important. p-toluenesulfonic acid (PTSA) catalyzed esterification of dihydrocaffeic acid (DHCA) with hexanol was selected as model reaction to investigate the synthesis of lipophilic antioxidant. The highest yield of hexyl dihydrocaffeate was achieved under the following optimum conditions: 1 mol% PTSA, 1:30 molar ratio of dihydrocaffeic acid to hexanol without molecular sieves at 80 °C in 2 h. The relationship between temperature and the forward rate constant gave the activation energy of 22.6 kJ/mol, which indicated that PTSA possessed high catalytic activity in the synthesis of hexyl dihydrocaffeate. In addition, the activity of PTSA was not inhibited by the water produced during esterification process. Importantly, this esterification could even proceed smoothly when initial water content was below 5%. In addition, the esterification of a set of phenolic acids could take place efficiently under the same conditions affording the corresponding esters in good to excellent yields. This established method will provide an efficient method for produce lipophilic antioxidants from various natural phenolic acids.Supported by Scientific and Technological Project of Henan Province (No. 182102110024) and Basic Research Funds of Henan University of Technology (No. 2015RCJH01). Keywords:: Dihydrocaffeic acid, Phenolic acids, Hexanol, p-toluenesulfonic acid, Esterification, Antioxidant

Ursolic acid (UA) is a natural triterpene carboxylic acid with an underlying anti-hyperlipidemia effect. This study examined the mechanism of interactions of UA with cholesterol esterase (CEase), pancreatic lipase (PL), and micellar cholesterol solubility in vitro. The half-maximal inhibitory concentration (IC50) of CEase, PL, and micellar cholesterol solubility was determined to be 0.07 ± 0.01 mg/mL, 1.81 ± 0.13 mg/mL, and 1.73 ± 0.08 mg/mL, respectively. Multispectral combination revealed that UA changed the secondary structure and quenched the intrinsic fluorescence by static quenching of the two enzymes. The interactions were exothermic reaction as determined by enthalpy. Furthermore, molecular docking confirmed that UA was bound to amino acids of two enzymes at active site through hydrophobic interaction and van der Waals forces. Molecular dynamics (MD) simulation found that CEase and PL rearranged with UA to form stable complexes. The strong inhibition effect of CEase and PL mediated by UA might provide additional insight into understanding the role of UA in the hypolipidemic effect. [ABSTRACT FROM AUTHOR]

Dangers of Ignoring Market Friction When Leveraging Financial Portfolios Portfolio leveraging is a standard industry practice to target higher fund returns, for example, in risk parity asset allocation. However, the existing models of optimal bet sizing fail to integrate analytically the impact on leveraged portfolio selection resulting from market liquidity issues. The paper "Optimal Leveraged Portfolio Selection Under Quasi-Elastic Market Impact" considers a market in which both temporary and permanent impact on trading prices are present with the former impact being sufficiently large relative to the latter. Our analytical conclusions, supported by a case study that uses even relatively more liquid U.S. exchange-traded fund assets, demonstrate that fund managers are ill advised to ignore market friction when leveraging to achieve target higher returns. Not only risk-adjusted returns significantly deteriorate, but also those losses become steeper when setting higher targets requiring increased levels of leverage. Moreover, leverage-constrained and less risk-averse investors ignoring liquidity costs ex ante face the most losses in expected utility ex post. We study optimal portfolio choice under leveraging to improve portfolio performance when trade execution faces market impact. We consider a quasi-elastic market with continuous trading in which temporary liquidity costs are sufficiently large relative to permanent impact. The resulting convex optimization model is used to show analytically that an unlevered portfolio maximizing the Sharpe ratio is no longer a tangency portfolio, and increasing the portfolio target mean leads to severely undermining the risk-adjusted returns and requiring increased portfolio leverage. This paper develops theoretical properties underlying the relationships among target mean, leverage, and Sharpe ratio in optimal portfolio selection under market impact. The Sharpe-leverage efficient frontiers under market impact are consistently dominated when setting higher return targets. Moreover, leverage-constrained and less risk-averse investors ignoring liquidity costs ex ante suffer the most losses in expected utility. Detailed computational analyses are provided using real-world data to support and highlight our analytical findings. Funding: The research of the corresponding author, J. Chen, was partially supported by the National Natural Science Foundation of China [Grants 72171012 and 11801023]. Supplemental Material: The online appendix is available at https://doi.org/10.1287/opre.2023.2462. [ABSTRACT FROM AUTHOR]

Organic fertilizer applications and subsurface drainage are two important measures for improving coastal saline soil; however, nitrous oxide (N2O) emissions from saline soil under a combination of these two measures are seldom evaluated. In this study, saline soil cultivated with sunflowers (Helianthus annuus L.) was employed as an experimental system. Prior to the experiment, the saline soils were buried with three different spacings (10 m (S1), 15 m (S2), and 20 m (S3)) of subsurface drainage pipes. The nitrogen nutrients that are needed by sunflowers came from two different nitrogen sources (organic and inorganic fertilizer), including six application schemes of either 100% organic fertilizer (100%OF), 75% organic fertilizer combined with 25% inorganic fertilizer (75%OF), 50% organic fertilizer (50%OF), 25% organic fertilizer (25%OF), 0% organic fertilizer (0%OF), and no fertilizer (CK). The results show that the cumulative N2O emissions from the treatments under S1, S2, and S3 throughout the entire growth period were 8.9–15.8, 9.5–17.5, and 10.1–17.6 kg ha−1, respectively. A smaller spacing between adjacent drainage pipes or a higher replacement proportion of organic fertilizer reduced the accumulative N2O emissions. The increased replacement of organic fertilizer decreased the soil salinity, whereas it increased the C/N ratio and total carbon content. The fertilization treatments significantly increased the nitrogen uptake of sunflower plants, with increase ranges of 18.1–47.2%, 8.6–40.5%, and 8.8–34.5% under S1, S2, and S3, respectively, compared with CK. The highest yield of sunflowers was achieved under S2 combined with 25%OF, reaching 3.82 t ha−1. Correlation analysis showed that the N2O emission flux was positively correlated with the soil salinity, crop yield, and crop nitrogen uptake, whereas it was negatively correlated with the total carbon, C/N ratio, and organic carbon content. We concluded that using 25% organic fertilizer instead of inorganic fertilizer was beneficial for reducing N2O emissions while maintaining the crop yield under subsurface drainage. [ABSTRACT FROM AUTHOR]