Objective To investigate the distribution of hepatitis Bvirus (HBV) genotypes and drug resistance mutation sites in Kaifengarea. Methods A total of 200 hepatitis B surface antigen (HBsAg)positive patients were selected from Kaifeng area from January 2018 toDecember 2020. The genotype of the patients was detected by genesequencing technology, and the test results were statistically analyzed.Nucleoside analogues (NAs) resistance gene loci in serum HBV-DNA of 200untreated patients were analyzed. Results Among 200 HBsAg positivepatients in Kaifeng area, 179 cases were genotype C, accounting for ${97.8}\%,4$ cases were genotype B,accounting for ${2.2}\%$ , and no B+Cor other types were detected. Among the 200 patients, 26 were detectedNAs gene drug resistance mutation sites, and the detection rate of drugresistance mutation sites in patients with gene $\mathrm{C}$ was higher than that inpatients with gene B. Conclusion Hepatitis B surface antigen positivepatients in Kaifeng area of HBV genotype mainly $\mathrm{C}$ type, B type is less, no othergenotype was detected. The detection rate of NAs resistance sites ingenotype C was higher than that in genotype B. A total of 9 differentcombinations of NAs drug-resistant mutation sites were detected, mainlyunit point mutation.

The high and low temperature test chamber can provide thecorresponding high and low temperature environment for instruments andmaterials, and its temperature field performance and measurementuncertainty are important indicators that affect the measurement resultsof the temperature test chamber. Through the uncertainty evaluation andinfluence analysis of temperature deviation calibration results, themeasurement performance of high and low temperature test chamber, errorsources and methods to reduce the influence of error are furtherunderstood. According to the calibration method specified in GB/T10592-2023 Technical Conditions for High and Low Temperature TestChamber, select the temperature sensor that meets the measurementrequirements and calibrate the temperature deviation of the high and lowtemperature test chamber. The calibration confirms that the temperaturefield performance of the high and low temperature test chamber meets thetolerance requirement of temperature deviation $\pm {2}^{\circ }\mathrm{C}$ , and themeasurement uncertainty meets the technical index requirement of $1/3$ maximum allowable error. Thetemperature field performance of the high-low test chamber is good, andthe short-branch A-class platinum thermal resistance selected by themeasurement standard meets the calibration requirements and has goodstability.

Objective to analyze the impact of the application ofLaboratory Information Management System (LIMS) in laboratory testquality management on the existence of test return pass rate. Methods328 specimens were selected from the specimens tested in our laboratoryfrom January 2022 to December 2023, and were divided into routine team(January 2022-December 2022, routine quality management of tests) andsurvey team (January 2023-December 2023, quality management of testscompleted by LIMS system) according to the time, with 164 specimens ineach team. Comparison of specimen test reporting, adverse events andlaboratory staff satisfaction among the two teams. Results Comparing thetest reporting of specimens in the two teams, the critical value returnrate (95.73%), the timely rate of critical value reporting (96.95%), andthe qualified rate of test return (97.56%) were higher in the surveyteam $\left({{\chi }^{2}={6.821},{4.525},{5.878}, P <{0.05}}\right)$ ; and in thecomparison of the incidence rate of adverse events among the teams, thesurvey team (3.05%) was lower $\left({{\chi}^{2}= {4.525}}\right.$ , $P<{0.05}$ ); compared with before the implementation of LIMSsystem, the scores of laboratory staff efficiency $\lbrack \left({{9.12}\pm {0.55}}\right)$ points], management effectiveness [(9.16±0.57) points], and risk control[(9.27±0.54) points] were higher after the implementation $\left({t ={2.369},{2.270},{2.291}, P<{0.05}}\right)$ . Conclusion Laboratory test qualitymanagement under LIMS can improve test return pass rate, critical valuereturn rate and critical value return timely rate, reduce the risk ofadverse events, and improve the satisfaction of laboratory staffmanagement, with significant practical value.

Objective To evaluate and analyze the value of halophilicbacteria culture in the detection of Vibrio parahaemolyticus in seafoodin Dalian area. Methods 46 samples of Marine products were collectedfrom Dalian from July 2023 to October 2023, and halophilic bacteria werecultured and isolated. The salt-tolerance test was carried out toidentify and analyze the virulence of Vibrio parahaemolyticus, and thecharacteristics and detection of Vibrio parahaemolyticus in Marineproducts were analyzed. Results A total of 45 halophilic and salttolerant strains were screened, with a yield of 44.44% at 20% salinity,55.56% at 15% salinity, and 11.11% at 50°C cultivation environment. Theisolated strains continued to grow at a concentration of ${25}\%\mathrm{{NaCl}}$ , and the bestgrowth was observed at a concentration of ${10}\%\mathrm{{NaCl}}$ . Seventeenmoderately halophilic bacteria were detected, with a total of 28 salttolerant strains. Conclusion The detection rate of Vibrioparahaemolyticus in Marine products in Dalian area can be improved byusing halophilic bacteria culture detection. The results of virulenceidentification show that Vibrio parahaemolyticus has strong virulenceand potential risk of food poisoning.

With the improvement of people's living standards, food safety issues have become the focus of attention. Food microorganisms as an important indicator of food hygiene, which has an important role in ensuring food safety. To a large extent, determine the accuracy of the test results. This article conducts research and discussion of process control from the entire link of the medium procurement, acceptance, storage, preparation, use, and abandonment of the medium, which explains the measures to improve the quality of the medium. It is expected to provide some references for the effective development of food microorganisms.

Objective To establish an inductively coupled plasma massspectrometry (ICP-MS) method for the determination of $\mathrm{{Pb}},\mathrm{{As}},\mathrm{{Hg}},\mathrm{{Cd}},\mathrm{{Hg}}$ in astragali radix, crataegi fructus, lycii fructus, lonicerae japonicaeflos and glycyrrhizae radix et rhizome. Methods After microwavedigestion of forty-five batches of samples, the contents of five heavymetals in commom TCM decoction pieces were determinationed by ICP-MS.The RF power is 1550 W. Kinetic Energy Discrimination mode is used. Thecollisional gas was Helium.The carrier gas was Argon with ${0.8}\mathrm{\;L}/\mathrm{{min}}$ , theplasma gas flow rate was ${14.0}\mathrm{\;L}/\mathrm{{min}}$ . Results Five heavy metal elements showed a good linear relationships $\left({r >{0.999}}\right)$ , whoserecoveries were 84.6%~115.3%, the detection limit was ${0.0001}\sim {0.0140}\mathrm{{mg}}/\mathrm{{kg}}$ .Among the 45 batches of samples, there were individual samples oflonicerae japonicae flos that exceeded the limit. Conclusion This methodis simple, efficient, stable and reliable, which can be used for thequality study of a variety of heavy metals, and provides more basis forits quality control and scientific supervision.

Objective To establish a high-performance liquidchromatography method for the detection of dibenzothiazole disulfide(MBTS) in soil. Methods Extract using acetonitrile ultrasound for 30minutes, filter through an organic membrane filter, and purify through aC18 column. Use an HPLC analyzer with set flow rate of ${0.7}\mathrm{\;{mL}}/\mathrm{{min}}$ andcolumn temperature of ${40}^{\circ }\mathrm{C}$ , and the soilsample is separated for qualitative analysis and quantitative analysisusing external standard method at a detection wavelength of ${275}\mathrm{\;{nm}}$ . Results Byoptimizing the pre-treatment and chromatographic conditions for MBTSdetection, acetonitrile was used as the extraction solvent, C18 columnserves as the purification column. An appropriate gradient elutionprogram has a good effect on reducing matrix effects in soil andanalyzing target compounds. Through methodological validation, it wasfound that, the relative standard deviation of MBTS spiked precisionranges from 0.070% to 0.201%. The relative standard deviation of MBTSspiking accuracy ranges from 0.071% to 0.646%, and the spiking recoveryrate ranges from 91.0% to 97.1%, the detection limit of MBTS method is0.003 mg/kg, and the lower limit of determination is ${0.013}\mathrm{{mg}}/\mathrm{{kg}}$ . Conclusion This method has the advantages of simple operation, lowdetection limit, short testing time, low interference, high precisionand accuracy, and can provide technical support for the MBTS insoil.

Phosphorus is one of the important nutrient elements in the soil, which has an important influence on crop growth. The availability and availability of phosphorus elements vary in their morphology. Accurate and rapid analysis of phosphorus morphology in soil is crucial for rational fertilization and increasing crop yield. This paper discusses the rapid analysis method of phosphorus elements in soil morphology, introduces the determination of phosphorus including instrument working conditions setting, working curve and ICP method. The application of ICP method as a simple and easy detection method in phosphorus analysis was discussed, through the actual detection method to verify the accuracy and reliability of different detection methods. Finally, the comprehensive application of various methods can quickly and accurately analyze the morphology of phosphorus in soil.

Objective Analyze and evaluate the measurement uncertainty of phenylethanolamine A residue in beef using liquid chromatography tandem mass spectrometry. Methods By analyzing the detection process and mathematical model, the main sources of uncertainty in the residual amount of phenylethanolamine A are determined: uncertainty caused by detection equipment, uncertainty caused by standard and sample weighing, uncertainty caused by laboratory temperature, uncertainty caused by transfer and constant volume, uncertainty caused by sample pretreatment, and uncertainty caused by experimental repeatability. Results The measurement uncertainty of each component was calculated and the relative standard uncertainty $\left({{u}_{\mathrm{{rel}}}={0.11}}\right)$ was synthesized for the detection of phenylethanolamine A residue in beef by liquid chromatography-tandem mass spectrometry. The expanded uncertainty of the determination results was $\mathrm{U}\left( X\right)={0.11}\mathrm{{g}}/\mathrm{{kg}}$ . The detection result of measuring phenylethanolamine A in beef by liquid chromatography tandem mass spectrometry was: $X=\left({{0.51}\pm {0.11}}\right)\mathrm{{\mu g}}/\mathrm{{kg}}, k =2$ . Conclusion The detection equipment had the greatest impact on the measurement uncertainty of phenylethanolamine A residue, followed by sample pre-treatment, experimental repeatability, and transfer and constant volume. In daily testing, attention should be paid to the condition of the instruments and equipment, timely verification and calibration should be carried out, the experimental process, transfer and constant volume operation should be standardized, so that to minimize the impact of the above factors on measurement uncertainty as much as possible.

Objective To verify whether the laboratory can accurately detect fluoroquinolone residues in aquaculture products according to standard Methods. Methods In this article, according to the Methods of Determination of 17 Sulfonamides and 15 Quinolones Residues in Aquatic Products by Liquid Chromatography-Tandem Mass Spectrometry (Ministry of Agriculture Announcement No. 1077-1-2008) and Laboratory Quality Control Specifications for Food Physical and Chemical Testing (GB/T 27404-2008), the method validation of the determination of 5 fluoroquinolones residues in cultured aquatic products by Liquid Chromatography-Tandem Mass Spectrometry was carried out, including linearity range, method sensitivity, accuracy and precision. Results The results showed that the 5 target compounds had good linear relationships in the range of $0 \sim {100\mu}\mathrm{g}/\mathrm{{kg}}$ , with correlation coefficients above 0.99 . The method sensitivity (detection limit, quantification limit) met the method requirements, the average recovery rate was ${93.0}\%\sim {110}\%$ , and the relative standard deviation was $\leq {15}\%$ , all of which met the method requirements. Conclusion It indicates that the laboratory can correctly apply this method for detection work under the existing detection conditions.