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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.)

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.)

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group 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 Food & Fermentation Industries is the property of Food & Fermentation Industries 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 Tiangong University is the property of Journal of Tianjin Polytechnic 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 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.)

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board 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.)

BACKGROUND: Streptococcus mutans is an important pathogen of dental caries, and timely detection of its levels is of great significance for early detection and treatment of dental caries. OBJECTIVE: To evaluate the effect of loop-mediated isothermal amplification (FTA-LAMP) direct extraction of Streptococcus mutans DNA. METHODS: (1) Bacterial suspensions containing ATCC standard strains (Streptococcus mutans) were prepared and inoculated into the brain-heart leachate medium. After mixed thoroughly, the mixture was then diluted in a 10-fold gradient into seven concentrations (4.2×107, 4.2×106, 4.2×105, 4.2×104, 4.2×10³, 4.2×10², 4.2×10 CFU/ mL), two parallel controls were made for each dilution level, and sterile water was used as a blank control. (2) The DNA of Streptococcus mutans was extracted using FTA Elute card, boiling method, kit extraction and lysate extraction methods separately and then amplified using LAMP technology was amplified. A specificity test was also performed to compare the differences between the four DNA extraction methods. RESULTS AND CONCLUSION: The DNA extracted by all four methods met the requirements for LAMP amplification. Specificity test results showed that only Streptococcus mutans could specifically amplify the target gene. The detection limit value of the DNA concentration was 4.2×10³ CFU/mL for the lysate method, 4.2×104 CFU/mL for the FTA Elute card extraction method, 4.2×106 CFU/mL for the kit extraction method, and 4.2×107 CFU/mL for the boiling method. In the other aspects of the four extraction methods, the kit extraction method had the highest experimental cost, number of steps and time; the other three methods had the same number of steps, with the FTA Elute card method requiring the least amount of instruments, the boiling method having the lowest single cost, and the lysate extraction method taking the least amount of time. Only a small amount of bacteria were needed for successful extraction using both the FTA Elute card and lysate extraction methods. Compared with the FTA Elute card method, the lysate extraction method was superior in terms of time, but it had a high single cost and required more equipment. To conclude, the FTA-LAMP technology established in this study has the advantages of ease of operation, high specificity, high sensitivity, and visualization, which is expected to be a new way for efficient extraction and detection of Streptococcus mutans. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development 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.)

The purpose of this experiment is to optimize the methyl-esterification method of microencapsulated fat powder oil. The oil extracted from the samples using acid hydrolysis and petroleum ether. Take 50 mg of the oil and place it in a pressure-resistant vial, then add 2 mL 0.2 mol/L sodium hydroxide-methanol solution and sonicate in a water bath at 65 °C. After the saponification was complete, as indicated by phenolphthalein, neutralized with 1 mol/L sulfuric acid-methanol solution until the phenolphthalein is colorless. Then add another 300 µL of sulfuric acid-methanol solution and sonicate again in a water bath at 70 °C for 5 minutes. Add a saturated sodium chloride into aqueous solution to assist with phase separation, and extract with isooctane after a desiccating with anhydrous sodium sulfate. Determine the content using Gas Chromatography-Flame Ionization Detector (GC-FID), and evaluate the precision, accuracy, detection limit, and quantitation limit of the method. The results showed that the optimized method of fatty acids in soybean oil standard substance GBW (E) 100120 determined by the optimized method were consistent with the standard values, and the precision RSD was 1.25%. The comparison results between laboratories showed that the methyl-esterification rate of this method was more than 95%, the repeatability error limit RSD was 2.71%, and the reproducibility error limit RSD was 4.86%. The limit of detection and limit of quantitation of trans-oleic acid/ trans-linoleic acid were 0.004% and 0.011%, respectively. The study indicates that the methods used in the experiment are efficient, accurate, and environmentally friendly, which can provide references for the development of the oil industry and the revision of future standards. [ABSTRACT FROM AUTHOR]

Railway surveying is one of the important tasks in China's railway construction engineering. Through the unremitting efforts of several generations of railway surveyors, Chinese railway surveying technology has evolved from pure manual surveying and mapping at the beginning of the founding of the People's Republic to the current state of digitalization and automation, and is advancing towards intelligent surveying. This paper systematically summarized and reviewed the development history of surveying techniques in Chinese railway surveying process, including primary control surveying, 1:10 000 topographic mapping, 1:2 000 topographic mapping, centerline surveying, cross-section surveying, site topographic mapping, and existing railway surveying. It also studies the use of UAV LiDAR technology for special surveying tasks such as centerline and intersection surveying for new railways, achieving precision that meets the 10 cm limit requirement. New methods for conducting various surveying tasks on existing railways based on mobile laser scanning technology and UAV oblique photography surveying technology were introduced. The surveying precision essentially meets the requirements for existing railway centerline surveying with a planar detection limit difference of no more than 3cm and a general terrain elevation detection limit difference of no more than 5 cm. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group 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 Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group 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 Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group 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 Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group 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 Guangdong University of Technology is the property of Journal of Guangdong 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 Science & Technology of Food Industry is the property of Science & Technology of Food Industry 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 Brewing is the property of China Brewing 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.)

In order to explore the identification method of hydroxyl safflower yellow A in natural dyes, which is distinguished from chemical synthetic dyes, a method Gr the quantitative analysis of hydroxyl safflower yellow A in natural dyes was developed by high performance liquid chromatography-tandem mass spectrometry. The samples "ere qualitatively and quantitatively analyzed in the multi reaction monitoring mode (MRM), 25% methanol aqueous solution was used for extraction, the flow rate of mobile phase was 0.25 mL/min, the sample volume was 5 µ L, the column temperature was 40 °C, and methanol-10 mmol/L ammonium acetate aqueous solution was used as mobile phase, then separated by Perkin Elmer column C18 (2.7 µ m, 2.1 mm x 100 mm) The results show that the linear relationship is good when the mass concentration is 0.02-2.00 mg/L, and the fitting degree is higher than 0.999 0. The limit of detection was 0.125 µ g/L, and the limit of quantitation was 0.42 µ g/L, and the recovery was between 80% and 95% at different concentrations; This method can provide an efficient and sensitive detection scheme for the determination of hydroxyl safflower yellow A, and also provide a reference for the product quality determination of natural dye-dyed textiles. [ABSTRACT FROM AUTHOR]

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 Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica 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 Food & Fermentation Industries is the property of Food & Fermentation Industries 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.)

Introduction of meta-aramid units into poly (p-phenylene terephthalamide) (PPTA) allows regulation of its crystallization and processing properties, therefore, quantitation of the meta units in PPTA is of practical importance. In this paper, blends of PPTA with poly (m-phenylene isophthalamide) (PMIA) were prepared and analyzed by infrared and Raman spectroscopies. In the infrared spectra, it was found that the absorption band at 659 cm−1 attributed to C—H in-plane wagging vibration of the m-disubstituted benzene ring can be utilized for quantitative analysis of PMIA, the intensity of which exhibited good linear relationship with PMIA content, allowing detection of meta units of 2. 0% (mass percent) and above. In the Raman spectra of the blends, the breathing vibration of the meta-disubstituted benzene ring at 1002 cm−1 characteristic of PMIA was found to exhibit an intensity proportional to its content with excellent linear correlation, which enabled detection of meta units of a low content of 0. 25% (mass percent）. In conclusion, the Raman method is more accurate with a lower detection limit, and therefore is superior to the IR method for quantitation of meta units in para-aramids. [ABSTRACT FROM AUTHOR]

A method for determination of the migration of three new plasticizers, triisooctyl phosphate (TOP), diisooctyl sebacate (NINS) and diisooctyl 1,2-cyclohexane dicarboxylate (DEHT), in six food simulants was established. A liquid chromatography-tandem quadrupole time-of-flight high resolution mass spectrometer (HPLC-QTOF) was used to separate the target substances by gradient elution on a T3 column (100 mmx2.1 mm, 2.7 µm) with methanol and 5 mmol/L ammonium formate as the flow, and the detection was carried out under information dependent acquisition mode (IDA). Besides, the migration of positive biodegradable food contact material samples at different contact times, temperatures and food simulants was studied. The results showed that the three new plasticizers had good linearity (R²>0.99) in the concentration range of 0.005~0.250 mg/L, the detection limit was between 0.1~0.9 µg/L, and the recovery rate was between 79.3%~108.0%, while the RSD was between 0.84%~9.80%. The migration regularity showed that under the same conditions, in 50% ethanol simulant results the highest migration rate of TOP, and in 95% ethanol simulant results the highest migration rate of NINS. The amount of migration increases with the increase of temperature and migration time, while the migration increases rapidly first and then tends to equilibrium after 4 days. This research could provide technical support for the quality control of biodegradable food contact materials for enterprises and regulatory agencies. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher 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 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.)

Copyright of Control Theory & Applications / Kongzhi Lilun Yu Yinyong is the property of Editorial Department of Control Theory & Applications 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 Food & Fermentation Industries is the property of Food & Fermentation Industries 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 Food & Fermentation Industries is the property of Food & Fermentation Industries 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 Food & Fermentation Industries is the property of Food & Fermentation Industries 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.)

The experiment aims to establish a convenient and rapid universal quick purification column as a pre-treatment method, shortening the pre-treatment time by optimizing steps such as extraction and purification, and conducting rapid quantitative analysis of common mycotoxins in feed. The experiment has established an UPLC-MS/MS method for the rapid determination of seven mycotoxins in feed based on the Myco purification column filled with MOFS materials. The feed sample is extracted with acetonitrile-water, vortexed, loaded and purified through the Myco purification column, with 5 mmol/L ammonium formate-methanol as the mobile phase, and quantified by the external standard method using UPLC-MS/MS. The results show that the seven mycotoxins have a good linear relationship in the range of 0.5~500 μg/L, with a correlation coefficient (R2) > 0.99. The method detection limit is 0.5~2.0 μg/kg, and the quantification limit is 2.0~ 5.0 μg/kg. The recovery rates of the seven toxins at low, medium, and high levels of spiking in blank samples are 82.3%~ 96.8%, with relative standard deviations of 2.1%~9.3%. The results indicate that the UPLC-MS/MS method established based on the Myco purification column for the rapid determination of mycotoxins in feed is simple to handle and reliable, suitable for the quantitative determination of the seven mycotoxins in most feeds. [ABSTRACT FROM AUTHOR]

This study utilized water-soluble fluorescein isothiocyanate (FITC) to cover graphene loaded gold nanoparticle composites, and the fluorescence of the probe molecule FITC was quenched. Then, by adding cyanide to the system, the strong complexation of cyanide ions (CN-) with gold nanoparticles formed a stable complex Au (CN)3-x, gradually restoring the fluorescence of the probe molecules, thereby achieving rapid detection of cyanide. The pH value of the experimental solution, reaction time, and interfering ions were optimized. The experimental results indicated that the FITC-Au NPs fluorescence probe had a minimum detection limit of 0.036 μmol/L for CN- in the presence of an H2O2 environment. There was a good linear relationship within the 0.05-80 μmol/L concentration range. The high stability and selectivity of FITC-Au NPs probes were utilized to achieve rapid detection of CN- in complex samples. This simple, fast, and economical fluorescence sensing system shows great practical potential in the detection of anions in actual samples. [ABSTRACT FROM AUTHOR]

A rapid and simultaneous lateral flow immunochromatography (LFIC) method was established based on colloidal gold (CG) for testing three addictive drugs in milk tea, including methamphetamine (MET), ketamine (KET), and cocaine (COC).After optimizing the key parameters, such as the concentration of coated antigen, the combination position of the three analytes, and the immunoreaction time, the developed method could be used for the simultaneous identification of three target addictive drays in a milk tea sample with a lower concentration could be tested.The limits of detection of MET, KET, and COC were 1.60, 1.59, and 1.39 ng/mL, respectively.In milk tea samples, the mean recoveries of the three types of mixed reference analytes ranged from 90% to 109% with a relative standard deviation of less than 5%.Briefly, the multiple CG-LFIC method had the advantages of easy operation, fast analysis, high sensitivity, and good specificity.It can be an effective method for simultaneous screening addictive drugs in milk tea and provides promising applications in the bio-detection field. [ABSTRACT FROM AUTHOR]

In recent years, it has been reported that new psychoactive substances disguised as snacks, drinks, and other forms enter and lurk in the daily life of the public.Among them, fentanyl-related substances are typical representatives.Market supervision and public security investigation urgently need the support of on-site rapid screening technology and products.The rapid detection technology based on aptamers has developed rapidly, but the research on specific fentanyl aptamers is relatively lacking.In this study, tailoring aptamers of core structure analogues of fentanyl-related substances were used as recognition elements, Fe3O4 was used as quencher and magnetic separator, and fluorescence quenching technology was used to build an aptamer sensing platform to achieve broad spectrum recognition of the total amount of fentanyl.Results showed that the fluorescence sensor detected fentanyl in the range of 100-500 μg/L, R was 0.997 7, the detection limit was 19.7 μg/L, and the relative standard deviation was 5.91%-7.51%.The standard recoveries of non-residential water and residential water were 81.14%-91.54% and 106.7%-117.4%, respectively.This developed strategy can be used for the rapid screening of water samples of fentanyl and enrich the research on the wide-spectrum rapid detection of fentanyl-related substances. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry 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.)

The distribution pattern of rare earth elements (REEs) in uranium ore concentrates (UOC) is an important fingerprint information for geological source tracing in nuclear forensics. It is particularly important to accurately determine the content of rare earth elements in UOC. Because of the large amount of the uranium matrix effect, the ionization efficiency of rare earth elements is low when determined by ICP-MS, and the results are significantly low. It is most important to remove the uranium matrix for accurately determining rare earth elements in UOC. A rapid separation method for rare earth elements in UOC by study of experimental conditions of Eichrom TRU resin, such as equilibrium solution acidity of column, adsorption acidity, leaching acidity and volume of rare earth elements is established. The content of uranium in eluent is lower than ng/kg, the recovery of REEs ranges from 88.3% to 104.0%, and the detection limit of REEs through ICP-MS analysis is from 0.001μg/kg to 0.190μg/kg after the separation of uranium and rare earth elements in UOC by TRU Resin. This method is used to determine the standard material GBW04205 for uranium ore, and the measured values are consistent with the standard values. Further analysis of four samples of UOC from different sources shows that the method can accurately determine the rare earth elements in UOC. The established distribution pattern of rare earth elements is effective for the geographical traceability of UOC nuclear forensics. [ABSTRACT FROM AUTHOR]

A method of quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS) based on oxygen reaction mode was established for the accurate determination of trace impurity elements in superalloys. The effect of the collision/reaction mode on the removal of mass spectral interference was investigated. By contrast, the polyatomic mass spectral interference on the target element Cd can be effectively removed under oxygen dynamic reaction cell (DRC-O2) mode. The signal-to-noise ratio (SNR) peaked when the gas flow was 2 mL/min, and the detection limit was approximately three orders of magnitude lower than that under standard (STD) mode. In addition, the elimination mechanism of mass spectrometric interference was studied. It was found that for the element X (X=Rb, Nb, Mo, Cs, Ta, W or U), the conversion of the interferent species XO to the non-interferent species XOO is a spontaneous reaction when the bond energy of X−O bond is higher than that of O−O bond. Therefore, it is easier to generate ions of XOO species when there is adequate O2 present in the ion source, so as to eliminate XO interference. Based on these results, experiments were carried out to determine elements of Rb, Nb, Mo, Cs, Ta, W and U. The matrix simulated solutions containing high concentration of Mo, Nb, Ta, and W were used to evaluate the methodological parameters for the measurement of trace Cd, Ag, Au, and Hg impurities, respectively. The limit of detection (LOD) of the trance elements is 0.08-0.31 μg/g, the relative standard deviation (RSD) of the measurement is 2.3%-3.1% (n=6), and the spiked recovery is in the range of 98%-103%. The reliability of the method was further verified by certified superalloy reference materials. Finally, the trace impurities in three types of superalloy samples were measured. The results indicated that the proposed method can achieve rapid, reliable analysis with low detection limit. Besides, it can meet the measurement requirement of trace impurities when the main elements of Mo, Nb, Ta and W exist in superalloy. [ABSTRACT FROM AUTHOR]

[Objectives] A recombinase polymerase amplification(RPA)system was constructed for the rapid detection of Fusarium oxysporum f. sp. niveum (FON) in order to provide technical support for the rapid detection of watermelon wilt in the field. [Methods] The genome sequences of 11 pathogenic fungi, including FON, were downloaded from the NCBI website for bioinformatics analysis using Seq Hunter 2 software. Four specific gene fragments of FON were obtained by comparison and primers were designed and screened for them. The specificity and sensitivity of the primers were verified using polymerase chain reaction(PCR), and in addition, the specificity and sensitivity of the primers were verified using the established RPA detection system, and finally, the RPA detection evaluation of artificially inoculated watermelon plants was performed. [Results] The RPA detection system for FON was established, and the optimal reaction time(40 min)and optimal reaction temperature (30 ℃) of the amplification system of DNA constant temperature rapid amplification kit were explored, and the detection limit of the optimal reaction system was 100 pg·μL-1. When using the DNA constant temperature rapid amplification kit(colloidal gold test strip type)for amplification, it only needed to react at 38 ℃ for 12 min, and 50 μL of the amplified product diluted 20 times was detected with the colloidal gold test strip. After 5 min, the results could be judged, and the detection limit was 100 pg·μL-1. [Conclusion] The RPA detection system of FON was successfully constructed. The established RPA detection system could detect FON from the genomic DNA of infected watermelon plant tissues, which could provide technical support for the rapid detection of watermelon Fusarium wilt in the field. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Modern Laboratory Medicine is the property of Journal of Modern Laboratory Medicine 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.)

An ultra-sensitive lateral flow immunochromatography (LFIC) method based on europium nanoparticles (EuNPs) was established for the simultaneous and rapid detection of aflatoxin B1 (AFB1), zearalenone (ZEN), and ochratoxin A(OTA) in medicine and food homologous materials. By optimizing the key parameters such as the mass concentration of the coated artificial antigen, immobilized line position of the coated artificial antigen, mass concentration of the coated goat anti-mouse IgG, buffer pH, and immunoreaction time, the developed method could achieve the ultrasensitive and simultaneous identification of three target mycotoxins in one sample after a simple sample pretreatment. This method demonstrated a high specificity and sensitivity. The visual limits of detection of the AFB1, ZEN, and OTA standards were 0.5, 4.0, and 2.0 ng/mL, respectively. Their linear ranges (IC10~IC90) were 0.03~4.61, 0.12~8.47, and 0.09~8.26 ng/mL, respectively. In the detection of mycotoxins in ginseng, astragalus, and angelica samples, the mean spiked recovery rates of the three types of analytes ranged from 90.02% to 109.39%, with a relative standard deviation of less than 8.50%. The coincidence rate between the actual sample and HPLC method was 100%. Therefore, the developed EuNP-LFIC method is suitable for the on-site rapid monitoring of mycotoxins such as AFB1, ZEN, and OTA in medicine and food homologous materials. [ABSTRACT FROM AUTHOR]

This study aimed to establish a time-resolved fluorescence immunoassay method for the simultaneous quantitative detection of fumonisin B1, B2 and B3 in corn. The EDC/NHS active ester method was used to prepare time-resolved fluorescent microspheres and fumonisin antibody conjugates. Fumonisin antigen was immobilized on a nitrocellulose membrane as the test line. By optimizing the number of test line, a competitive immunoassay method for detecting fumonisin was eventually established. Subsequently, the sensitivity, specificity, accuracy, precision, and correlation with the national standard method were evaluated for the established method. The detection limits of the established method by using two test line pattern were 107.68-168.28 μg/kg, and the quantification limits were 283.46-444.63 μg/kg. The cross-reactivity with fumonisin B1, fumonisin B2 and fumonisin B3 were 100%, 85.59% and 72.72%, respectively, and no significant cross-reactivity was observed with five other common mycotoxins. The recovery rates ranged from 88.37% to 117.42%, and the coefficients of variation were lower than 10%. The conformity of the results obtained by the established method, as compared to the immunoaffinity column purification-high performance liquid chromatography (IAC-HPLC) method specified in the national standard GB 5009.240-2016, fell within the range of 92.17% to 107.21%. The established time-resolved fluorescence immunoassay method meets the requirements for rapid on-site quantitative detection of fumonisin B1, B2 and B3 in corn. [ABSTRACT FROM AUTHOR]

Copyright of China Brewing is the property of China Brewing 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.)

Objective To establish a method for detecting the 2019 novel coronavirus subgenomic RNA (sgRNA), and evaluate the performance of the established method. Methods Primers and probes were designed according to the subgenomic sequence of the 2019 novel coronavirus, and a reverse transcription PCR method for sgRNA detection was established. The established method was optimized, including the concentration and proportion of primers and probes, extension temperature, reaction volume and template amount. The performance of the method was evaluated, including the limit of detection, sensitivity, specificity and repeatability. sgRNA and genomic RNA (gRNA) were detected in clinical samples, and the results were analyzed. Results In this study, an RT-PCR method for the detection of sgRNA of the 2019 novel coronavirus was established. The limit of detection of this method was 100 copies/mL, and the detection results of common pathogens were negative. The CV of sgRNA in high, medium and low concentration samples were less than 5%. sgRNA was positive in 115 suspected 2019 novel coronavirus infected patients (115/330, 34.85%). When the Ct value of gRNA-N was less than 30, the positive rate of sgRNA was 100.00%. When the Ct value of gRNA-N was in the range of 30-32, the positive rate of sgRNA was 68.75%. When the Ct value of gRNA-N was in the range of 32-35, the positive rate of sgRNA was 44.44%. When the Ct value of gRNA-N was greater than 35, the sgRNA was negative. Conclusion The RT-PCR method for the detection of sgRNA of the 2019 novel coronavirus was established, and the detection method was sensitive, specific and reproducible. [ABSTRACT FROM AUTHOR]

Much attention has been given to the efficient detection of Microcystin-LR (MC-LR), a kind of neurotoxin and carcinogen that has been verified by WHO. This paper describes the trial-producing of a sensor for MC-LR detection, which involves thiol aptamers being directly bonded to the gold electrode surface of the screen-printed electrode by the action of gold sulfur bonds, forming an Apt@Au sensitive interface. The aptamer on the sensitive interface interacts with MC-LR in the sample, causing changes in electron conduction of [Fe(CN)6]3-/[Fe(CN)6]4- and an increase in differential pulse voltammetry (DPV) response current, thus an Apt@Au sensor for MC-LR detection is made. Under the optimized testing condition, the sensor ' s detection linear range is between 0.001~50.00 µg/L, and the detection limit reaches 0.001 µg/L. Being good in selectivity, the sensor shows no significant signal response to Microcystin-LA, Microcystin-YR, nodularin toxin, and metal ions commonly found in the water body, and its application to synthetic water samples shows good recovery rates. In short, the Apt@Au sensor for detecting MC-LR has advantages in terms of simple operation flow and high detection sensitivity, showing a good application prospect. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Preventive Veterinary Medicine / Zhongguo Yufang Shouyi Xuebao is the property of Chinese Journal of Preventive Veterinary 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 develop a TTV detection technique with higher sensitivity and specificity, providing crucial technical support for uncovering the role of TTV in process of various diseases. Methods: For more accurate and sensitive TTV detection, this study analyzed all published subtypes of TTV genome sequences, on the basis of which a real-time PCR assay targeting the UTR was established and compared with the more widely used PCR assays reported in the references. Results: The method established in this study showed good linear relationship within the range of 1 x 107 to 1 x 101 copies/µ L standard sample concentrations, with a correlation coefficient of 1.000, a slope of -3.446, and a detection limit of 1 x 101 copies/µ L. The repeatability test results demonstrated an intra-assay coefficient of variation of 7.22%, indicating strong repeatability and stability of the method. Compared with four sets of primers widely used in previous studies, our established real-time PCR detection method showed significantly higher sensitivity (P<0.01) in detecting 30 clinical samples. Sanger sequencing results confirmed that all 30 positive samples detected by our method were TTV-positive, with a detection specificity of 100%. Conclusion: This study adopts a realtime PCR detection method based on the TaqMan probe, which has high sensitivity and wide coverage of genotype range, especially for quantitative detection in cases of low TTV viral load. It provides important technical support for the pathogenicity of the TTV virus and its application as an immune marker. [ABSTRACT FROM AUTHOR]

Thioflavin T (ThT) can bind to G-quadruplex through non-covalent interaction to form G-quadruplex/ThT complex, showing strong fluorescence intensity, while free ThT fluorescence is very weak. In the presence of florfenicol (FF), the high affinity of the aptamer (Apt) with a G-quadruplex structure to the target enables the formation of the Apt/FF complex and the release of ThT, resulting in a decrease in fluorescence intensity. Based on this feature, this study designed a sensitive and rapid on- site detection system for the detection of florfenicol, a label-free fluorescent aptasensor based on G-quadruplex/thioflavin T. The detection range of this aptamer sensor was 0.0128-200 ng/mL, the actual detection limit was 0.0128 ng/mL, and the total detection time was 10 min. At the same time, the recovery rate of the actual spiked samples (milk and eggs) was calculated, and the spiked recovery rate was between 91.2% and 117.1%. The established label -free fluorescent aptasensor has the advantages of high specificity, low cost, and short time - consuming, and can be used for on-site detection of actual samples. [ABSTRACT FROM AUTHOR]

Salmonella is the main cause of human diarrhea worldwide, which seriously endangers human and animal health. Traditional detection methods are time -consuming and cumbersome, so it is of great significance to carry out rapid, simple and sensitive visual detection methods. In this paper, a probe that can bind to the target sequence was designed and combined with gold nanoparticles (AuNPs). The target sequence was amplified by saltatory rolling circle amplification (SRCA). After denaturation at high temperature, it became a single chain. After binding with the probe on gold nanoparticles, gold nanoparticles were released. Under the action of MgS04, the aggregation showed blue visible to the naked eye, which was judged to be positive and negative to be purple. Therefore, a simple, fast and sensitive visual detection method was established. The results showed that the method had good specificity and could distinguish 8 Salmonella positive and 8 non -Salmonella negative. The sensitivity of visual detection was 5.5 x100 CFU/mL. The milk samples were artificially contaminated with Salmonella, and the detection limit was 3.7x100 CFU/mL. Comparison with GB 4789.4-2016 method for detection of 50 actual samples, the sensitivity of this method was 100.00%, the specificity was 97.87%, and the coincidence rate was 98.00%. The SRCA-AuNPs visual detection method established in this paper has high application value, and the results are visible visually, which is suitable for on-site visual detection and grassroots units. [ABSTRACT FROM AUTHOR]

Debranching enzymes are unable to fully meet the requirements of green production of starch sugars and comprehensive utilization of by-products. Therefore, it is necessary to explore suitable new types of debranching enzymes. This study screened an oligo-1,6-glucosidase gene (oga) from Paenibacillus sp. STB16 and constructed its Bacillus subtilis expression system. This system achieved heterologous expression of the oligo-1,6-glucosidase. The enzymatic properties and substrate specificity of the recombinant oligo-1,6-glucosidase were explored. The results showed that the enzyme activity of the fermentation supernatant of B. subtilis could reach 162.33 U/mL. The recombinant oligo-1,6-glucosidase had the optimum reaction temperature at 50 °C and optimum reaction pH at 6.0. It specifically acted on the &#945-1, 6-glycosidic bonds of branches with degree of polymerization of 1. Compared to other types of debranching enzymes (substrate conversion rate under the detection limit), the recombinant oligo-1,6-glucosidase exhibited stronger hydrolytic activity towards isomaltose, isomaltotriose, and panose. The substrate conversion rate reach 97.4%-100%, with glucose as the product. Therefore, it is more suitable for treating glucose mother liquor. The glucose content in the first mother liquor, second mother liquor and tail liquor of chromatographic separation was significantly increased by 3.6%, 12.7% and 34.4%, respectively. The research results provide a theoretical basis for the development and utilization of new types of debranching enzymes, and also serve as an important reference for the comprehensive utilization of by-products in starch sugar processing. [ABSTRACT FROM AUTHOR]