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The ethanol extract from Inula salsoloides (Turcz.) Ostenf was found to cause high mortality against Plutella xylostella L. (Lepidoptera: Plutellidae). The active components were isolated and identified. Two compounds were obtained and identified to be inulasalsolin and taraxasterol. Both compounds showed anti-feedant effects against third instar larvae of P. xylostella with AFC50 of 0.030 and 0.053 mg/mL and insecticidal activities with LC50 of 0.19 and 0.49 mg/mL, respectively. The two compounds also exhibited high toxicity to cabbage aphid, Brevicoryne brassicae L. (Hemiptera: Aphididae) with LC50 values of 0.021 and 0.098 mg/mL. This is the first report on the study of insecticidal components of I. salsoloides and their activity against insects. [ABSTRACT FROM AUTHOR]

To guide selection of the appropriate mechanical production mode within a certain area, the government and producers should make a choice according to production efficiency of the mode and to optimize its efficiency. The research sorted mechanization production mode, based on the degree of used agricultural machinery under a certain type of organizers in the production process (The organizers' type such as: individual farmer, family farm, agricultural production cooperatives for their own use machinery, agricultural machinery service cooperation, agricultural enterprise for their own use machinery, agricultural enterprise provide agricultural machinery operation service. The degree of used agricultural machinery is divided into 8 levels: less than 4 processes, with 4-7 processes, more than 7 processes, or fully mechanized are in 10 ones for field production, and on the basis of the above four types field production extended to postpartum processing), and focused on efficiency of 24 typical modes with Paddy rice- wheat rotation planting in double crop production area in Jiangsu province. The primary data was collected from field investigated, and for respectively output targets to a money income for government or the grain yield for producers. The DEA-Tobit method was applied for analyzing the different patterns under different output object for production efficiency and the influence factors. The relationship between production mode and its efficiency was obtained. In addition, including to the relationship between the efficiency and a few influence factors with mechanized production were analyzed. Results of this study clearly provide to us, the efficiency is significant difference under each output targets. If we want to obtain high efficiency based on object for money income, it shows that efficiency is higher in mechanized production pattern of the characteristics, which is more high degree of using agricultural machinery operation in the production process, and which is cooperation organization or the agricultural enterprise with the agricultural machinery to do some operation service for the planting farmers. However, if we want to high efficiency focus on yield production, the members participate in mechanized production with local and for their own use agricultural machinery, and the patterns of mechanization operation is in large proportion. And the efficiency is related to the six factors, such as financial subsidy accounts for total investment, the cultivated area condition, educated labors are the great positive effected factors to efficiency of production patterns. The proportion of agricultural machinery and laborer, on average monetary value of machinery, and the planting area for each laborer are affected efficiency to the different production patterns with positive or negative. And most of the mechanization production modes are in the scale of diminishing returns at the present situation, that is affected to the investment option and management scale. Therefore, according to the different output targets, it should choose mode in higher degree of using mechanization production operation within a certain organizers, and for the efficiency adjust influence factors accordingly. The research results contribute to choose the suitable mechanization production mode, and provide reference ways to improve the efficiency for the producers and government. [ABSTRACT FROM AUTHOR]

Nonlinear regression algorithms have been extensively applied in the parametric analyses of electrochemical impedance spectroscopy (EIS). However, the problem of how to provide good initial estimates of parameters automatically has not been thoroughly solved yet. For this reason, this paper offers a hybrid algorithm, which consists of the genetic algorithm (GA) based on probability theory and the deterministic computation based on analytic theory. The paper improves the usual GAs and puts forward the concept of weighting mutation. The hybrid algorithm overcomes the shortcoming that the usual GAs are liable to produce premature convergence. This paper has preliminarily solved the problem of how to produce good initial estimates of parameters automatically by a program design in the data processing of EIS. In principle, the design idea of the hybrid algorithm is of universal validity and can be used for solving the problem of how to provide good initial estimates of parameters automatically, which appears in many kinds of nonlinear regressions. [Copyright &y& Elsevier]

Abstract: A special method “conduit synthesis technology” has been utilized to produce spherical nickel hydroxide powders with different chemical compositions. Three kinds of powers A, B, C were prepared by chemically coprecipitating Ni, Co, Zn, Ca, Mg and Cu. It was found that powder B produced better performance than the others. The discharge capacities of powder B could achieve 280mAhg−1 for both 1C and 2C rates at 65°C, respectively. The cyclic voltammetry analysis showed that the difference between the oxidation potential and the oxygen evolution potential of powder B is 122mV. It indicated that Co could improve conductivity of electrons, restrict the oxygen evolution reaction and thus promote the high rate charge/discharge and high-temperature performance. Ca and Mg might effectively enhance the oxygen evolution potential in the charge process. Furthermore, the proper addition of Zn, Ca and Cu could lower the ionization energy and elevated the transition energy, and thus the transfer of electrons in electrode materials was accelerated and the electrochemical performance of nickel hydroxide electrode was improved. It was a promising way to improve the electrochemical performance of spherical nickel hydroxide for Ni–MH batteries. [Copyright &y& Elsevier]

To improve the adsorption affinity and selectivity of fipronils (FPNs), including fipronil, its metabolites and analogs, a magnetic covalent organic framework (Fe 3 O 4 @COF-F) with copious fluorine affinity sites was innovatively designed as an adsorbent of magnetic solid-phase extraction (MSPE). The enhanced surface area, pore size, crystallinity of Fe 3 O 4 @COF-F and its exponential adsorption capacities (187.3-231.5 mg g -1 ) towards fipronils were investigated. Combining MSPE with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), an analytical method was established for the selective determination of fipronils in milk and milk powder samples. This method achieved high sensitivity (LODs: 0.004-0.075 ng g -1 ), satisfactory repeatability and accuracy with spiked recoveries ranging from 89.9% to 100.3% (RSDs≤5.1%). Overall, the constructed Fe 3 O 4 @COF-F displayed great potential for the selective enrichment of fipronils, which could be ascribed to fluorine‑fluorine interaction. This method proposed a feasible and promising strategy for the development of functionalized COF and broadened its application in fluorine containing hazards detection., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

To address the problem that the low-density canopy of greenhouse crops affects the robustness and accuracy of simultaneous localization and mapping (SLAM) algorithms, a greenhouse map construction method for agricultural robots based on multiline LiDAR was investigated. Based on the Cartographer framework, this paper proposes a map construction and localization method based on spatial downsampling. Taking suspended tomato plants planted in greenhouses as the research object, an adaptive filtering point cloud projection (AF-PCP) SLAM algorithm was designed. Using a wheel odometer, 16-line LiDAR point cloud data based on adaptive vertical projections were linearly interpolated to construct a map and perform high-precision pose estimation in a greenhouse with a low-density canopy environment. Experiments were carried out in canopy environments with leaf area densities (LADs) of 2.945-5.301 m 2 /m 3 . The results showed that the AF-PCP SLAM algorithm increased the average mapping area of the crop rows by 155.7% compared with that of the Cartographer algorithm. The mean error and coefficient of variation of the crop row length were 0.019 m and 0.217%, respectively, which were 77.9% and 87.5% lower than those of the Cartographer algorithm. The average maximum void length was 0.124 m, which was 72.8% lower than that of the Cartographer algorithm. The localization experiments were carried out at speeds of 0.2 m/s, 0.4 m/s, and 0.6 m/s. The average relative localization errors at these speeds were respectively 0.026 m, 0.029 m, and 0.046 m, and the standard deviation was less than 0.06 m. Compared with that of the track deduction algorithm, the average localization error was reduced by 79.9% with the proposed algorithm. The results show that our proposed framework can map and localize robots with precision even in low-density canopy environments in greenhouses, demonstrating the satisfactory capability of the proposed approach and highlighting its promising applications in the autonomous navigation of agricultural robots., Competing Interests: Author XZ was employed by company Beijing PAIDE Science and Technology Development Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Tan, Zhao, Zhai, Fu, Chen and Yang.)

A new kind of convenient, low-cost double-potential ratiometric ECL sensing platform for the quantification of Cu 2+ was developed with carbon nitride nanosheets (g-C 3 N 4 NSs) and graphene quantum dots (GQDs) as ECL luminophores. g-C 3 N 4 NSs mixed with multi-walled carbon nanotubes (MWCNTs) was immobilized on a glass carbon electrode (GCE) and produced strong cathodic ECL at a potential of -1.2 V (vs. Ag/AgCl), while GQDs in the solution gave anodic ECL at +2.5 V. MWCNTs were used here to amplify the ECL signal of g-C 3 N 4 NSs. The addition of Cu 2+ causes the cathodic ECL signal from g-C 3 N 4 to decline, while the anodic ECL signal from GQDs remains unchanged. With the anodic ECL signal as an internal reference, a double-potential ratiometric ECL sensing platform for Cu 2+ was established. The ratio of the cathodic signal intensity to anodic signal intensity showed a linear response to the Cu 2+ concentration over a range from 5.0 × 10 -10 to 1.0 × 10 -6 mol L -1 and the detection limit was 0.37 nmol L -1 (3σ/S). Such a construction strategy alleviates the interference from the environment and therefore improves the detection accuracy of Cu 2+ . Compared with other methods for Cu 2+ detection, this method is simpler and more sensitive.

Food quality and safety are issues of concern to the government, food industry, and consumers; hence, it is imperative to detect harmful substances in foodstuff. Traditional techniques for this purpose include biochemical methods and instrumental analysis methods such as chromatography and chromatography-mass spectrometry. These methods, however, are time-consuming and unable to obtain the spatial distribution of the analytes. Therefore, the development of rapid, non-destructive, real-time, and visual detection technologies has emerged as a hotspot in the field of food research. In recent years, hyperspectral imaging, which combines imaging and spectral technology, is rapidly gaining ground. This technique allows one to determine the geometrical characteristics and chemical composition of samples. Compared with traditional spectral technologies, hyperspectral imaging has the advantages of wide detection ranges, in addition to being real-time and non-destructive. At present, hyperspectral imaging is widely used in meat quality evaluation, detection of adulteration, and meat classification. In addition, Raman imaging is mainly used for the detection of illegal additives in food and for adulteration detection. This technology is fast, non-destructive, and low cost; furthermore, spectral and spatial information of the targets can be simultaneously obtained. Mass spectrometry imaging allows for the visualization and high-throughput analysis of sample tissues, without the need for complex sample preparation steps such as labeling and staining. Compared with other imaging technologies, mass spectrum information of substances can be obtained by mass spectrometry imaging. As a molecular visualized technology, it helps obtain the spatial distribution of nutrients and harmful substances in food. Mass spectrometry imaging has unique advantages in food research, e. g., it is used for molecular-level detection and accurate positioning of substances, and hence, it has excellent application prospects in this field. In this paper, recent literature data about imaging technologies in the field of food research, including 72 reports published in professional local and overseas magazines, are collated. The principles of hyperspectral imaging, Raman imaging, and mass spectrometry imaging are introduced, along with the detailed applications of these methods in the quality detection, source identification, and microbial pollution of food. In addition, it also includes food physical damage, food adulteration and food chemical residues. Besides, the advantages and disadvantages of these imaging technologies are discussed. Finally, prospects for the development of imaging technologies in food research are presented. Future work related to hyperspectral imaging should focus on the development of high-sensitivity cameras and high-resolution systems. Improving the data processing efficiency and adding prediction models are also key points for the future. Future studies on Raman imaging can focus on the application of different chemometrics algorithms that would improve the evaluation of food quality and safety parameters. Expanding the scope of application of these methods in food research will also be the focus of future research. Regarding mass spectrometry imaging, attempts should be made to improve the ionization methods, detection sensitivity, spatial resolution, and data processing effectiveness. Additionally, the combination of spectral imaging and mass spectrometry imaging gives full play to their advantages, so that spectral and mass spectrometry information of the targets can be obtained. In short, the application of imaging technologies in food research is expected to be more promising.

Objective: To examine the effects of continuous and intermittent exercises on obesity and fatty liver in rats fed with high-fat diet., Methods: Wistar rats were randomly assigned into routine diet (R) and high-fat diet (H) groups, and each group were subdivided into sedentary group (S), continuous exercise (CE) group, and intermittent exercise (IE) group (n=8). In the CE group, the rats were forced to swim continuously for 90 min once daily, and those in the IE group swam for 30 min for 3 times (at a 4-h interval) daily. Both the CE and IE groups exercised for 5 days a week for 8 consecutive weeks. After the experiment, the retroperitoneal, epididymal, and visceral white and brown adipose tissues, the liver, and the gastrocnemius muscle of the rats were weighed. The lipogenesis rate was determined by incorporation of (3)H(2)0 into saponified lipids, and the blood lipid profiles were analyzed. The body weight and food intake of the rats were recorded daily., Results: IE appeared to be more efficient than CE in reducing the adverse effects of high-fat diet and sedentarism. Compared with CE, IE resulted in an improved lipid profile with reduced food intake, body weight gain, visceral and central adiposity, and fatty liver. The effect of high-fat diet and different exercises on weight gain, adiposity, fatty liver, and lipid profile in rats was associated to the manner of exercise, time of each session, age, gender, and length of observation period., Conclusion: Intermittent exercise is an important nonpharmacological strategy to control obesity and the related complications.

A new analytical method using ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS) was developed for screening and confirmation of 10 unapproved sedative drugs in feeds. The samples were extracted using the solution of methanol-0.1 mol/L HCl (9:1, v/v), and the extracts were centrifuged and then directly purified through MCX cartridges. The identification and detection were achieved in positive electrospray ionization (ESI) mode using Q-TOF-MS. The potential of UPLC-Q-TOF MS for confirmatory analysis was shown by determining the accurate mass of all the compounds and fragment ions upon collision-induced-dissociation (CID) at different energies. The extra mass measurement errors for all the sedative drugs were found to be within 5 ppm. The calibration graphs were linear in the concentration range of 5-100 microg/L with the correlation coefficients more than 0.99 for the 10 drugs. The limits of quantification (LOQ, S/N = 10) were 8 microg/kg for nitrazepam, zolpidem and thioridazine; 10 microg/kg for thriazolam, estazolam, diazepam, promethazine, chlorpromazine and midazolam; 20 microg/kg for clozapine. The recoveries for all the compounds in feeds were 60.6%-108.5% with the relative standard deviations less than 10% at the spiked levels of LOQ, 2LOQ and 4LOQ.

A screening method for 29 forbidden or limited synthetic pigments in cheese samples was established by liquid chromatography/quadrupole time-of-flight mass spectrometry (LC/Q-TOF MS). The pigments were extracted by n-hexane/water (3:1, v/v). After extraction, the n-hexane extract, water extract and residue, were obtained. The n-hexane extract was then cleaned-up by gel permeation chromatography (GPC). The water extract was extracted by acetonitrile, and the residue by ammonia water/methanol (1:99, v/v). The results showed that the 29 synthetic pigments with a wide range of polarities were extracted effectively with the recoveries between 70% and 95%, and matched well by Q-TOF MS precision mass searching to the mass spectral library with matching scores between 59. 66 and 99. 47. The quantitative analysis of the 29 pigments was carried out by Target MS/MS. The limits of detection (LODs) for 8 Sudan dyes were 0.4-2.5 micro/kg while for 21 water-soluble synthetic pigments were 20-80 microg/kg. The screening method is suitable for a wide range of synthetic pigments, and can be applied to food samples with proteins and fat in matrix.