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Salmonella enterica is a common pathogen in humans and animals that causes food poisoning and infection, threatening public health safety. We aimed to investigate the genome structure, drug resistance, virulence characteristics, and genetic relationship of a Salmonella strain isolated from patients with food poisoning. The pathogen strain 21A was collected from the feces of patients with food poisoning, and its minimum inhibitory concentration against commonly used antibiotics was determined using the strip test and Kirby-Bauer disk methods. Subsequently, WGS analysis was used to reveal the genome structural characteristics and the carrying status of resistance genes and virulence genes of strain 21A. In addition, an MLST-based minimum spanning tree and an SNP-based systematic spanning tree were constructed to investigate its genetic evolutionary characteristics. The strain 21A was identified by mass spectrometry as S. enterica, which was found to show resistance to ampicillin, piperacillin, sulbactam, levofloxacin, and ciprofloxacin. The WGS and bioinformatics analyses revealed this strain as Salmonella Enteritidis belonging to ST11, which is common in China, containing various resistance genes and significant virulence characteristics. Strain 21A was closely related to the SJTUF strains, a series strains from animal, food and clinical sources, as well as from Shanghai, China, which were located in the same evolutionary clade. According to the genetic makeup of strain 21A, the change G > A was found to be the most common variation. We have comprehensively analyzed the genomic characteristics, drug resistance phenotype, virulence phenotype, and genetic evolution relationship of S. Enteritidis strain 21A, which will contribute towards an in-depth understanding of the pathogenic mechanism of S. Enteritidis and the effective prevention and control of foodborne diseases.

Abstract In this experiment, a fixed bed of pyrolysis was used to conduct pyrolysis with coal and a mixture of coal and catalyst, and the distribution and composition of tar products were studied. The pyrolysis of raw coal was carried out at different temperatures and at different constant temperature times, and the effects of pyrolysis temperature and constant temperature pyrolysis time on tar product formation from raw coal pyrolysis were studied. γ-Al2O3 was used as the carrier, and 4 kinds of alkaline earth metal oxides (MgO, CaO, SrO, BaO), 3 kinds of subgroup metal oxides (Fe2O3, Co2O3, NiO) and 5 kinds of VIII metal oxides (Cr2O3, MnO2, CuO, ZnO, MnO2) were selected as active components. The supported γ-Al2O3 catalyst was prepared by the method of equal volume impregnation and roasting in a muffle furnace. The γ-Al2O3 catalyst was characterized by means of XPS, BET and SEM, and the mechanism of the mixed pyrolysis of coal with different metal oxide supported catalysts to generate tar was studied. The results showed that: (1) under the conditions of 450 °C, 500 °C, 550 °C and 600 °C, the maximum tar yield was 0.32 g at 600 °C, and the tar yield was higher at constant temperature for 15 min than at final temperature of 600 °C, with an increase of 15.63%. (2) Fe2O3/γ-Al2O3 catalyst resulted in the highest tar yield of 0.75 g, which was 134.38% higher than that of coal pyrolysis. (3) From the increase of light oil and phenol oil and the decrease of anthracene oil and asphalt, Co2O3/γ-Al2O3, Fe2O3/γ-Al2O3 and Cr2O3/γ-Al2O3 can improve the tar quality better.

The Pingdingshan mining area mined by China Pingmei Shenma Group is a typical example of deep mining. After 70 years of development, the group always insists on leading production with scientific and technological strength, ensuring safety with technical equipment, deepening its understanding of gas, and has gone through three stages of “passive prevention, active treatment and green use”. The monitoring and warning technology of dynamic disaster can predict the probability of disaster occurrence in advance, and the accuracy of predicting no dynamic disaster can reach 100%. The accuracy rate of power disaster is 80%, so that gas disaster can be prevented and controlled; The efficient anti-reflection extraction technology of gas in low-permeability coal seam reduces the gas treatment cycle from 24 months to 8 months, and the cost of gas treatment for tons of coal is reduced by 60%. The integrated green development and utilization technology of gas “extraction – power generation – refrigeration” can effectively reduce the roadway temperature by 5–10 ℃, increase the gas extraction concentration to 50%, guarantee the mine heating in winter and refrigeration in summer, save 60 000 kW·h of electricity consumption per day, not only eliminate the gas threat, make the mine gas become treasure, but also ensure the national coal supply security. Meet the development needs of the “double carbon” goal. In the future, based on the prevention and control of deep dynamic disasters, the group will actively promote the green utilization of coal transformation, build an industrialization road of safe mining, efficient washing and green transformation of coking coal resources, promote the rapid transformation and upgrading of enterprises, build a leading scientific research and innovation platform in the industry, ensure the security of national energy supply and keep up with the pace of social and economic development.

Objective To investigate the related symptoms, symptom cluster and influencing factors among patients with gynecological cancer during chemotherapy. Methods A total of 430 inpatients with gynecological cancer treated by chemotherapy were investigated by using the General Information Questionnaire and Chinese version of M. D. Anderson Symptom Inventory (MDASI). Results There were many symptoms in gynecological cancer patients during chemotherapy. The top three symptom incidence were vomiting (91. 86%), drowsiness (90. 70%) and fatigue (90. 00%). The top three incidence of symptomatic distress were walking (76. 74%), interpersonal (76. 30%) and emotion (72. 79%). Four symptom groups were extracted by exploratory factor analysis, namely emotional symptom cluster, disease symptom cluster, fatigue symptom cluster and digestive tract symptom cluster. Multivariate stepwise regression analysis showed that metastasis, family monthly income, recurrence, expected hospital stay, number of chemotherapy, chemotherapy regimen, tumor staging and work status were the influencing factors of symptoms. Conclusion There are many symptoms in gynecological cancer patients during chemotherapy. Clinical nurses should start from the point of view of symptom cluster, and provide effective symptoms management measures for patients, to improve their quality of life. (目的 调查妇科恶性肿瘤化疗患者的相关症状, 探讨其症状群的种类以及影响因素。方法 采用一般资料调查表、中文版安德森症状评估表(MDASI)对430名住院妇科恶性肿瘤化疗患者进行调查。结果 妇科恶性肿瘤化疗患者存在多个症状, 症状发生率排名前3位为呕吐(91. 86%)、瞌睡(90. 70%)和疲劳(90. 00%)。症状困扰发生率排名前3位为行走(76. 74%)、人际(76. 30%)、情绪(72. 79%)。探索性因子分析提取出4个症状群, 分别为情绪症状群、疾病症状群、疲乏症状群和消化道症状群。多元逐步回归分析显示肿瘤转移、家庭人均月收入、是否复发、本次预计住院天数、化疗次数、化疗方案、肿瘤分期和工作状况是症状群严重程度的影响因素。结论 妇科恶性肿瘤化疗患者存在多个症状群, 临床护理人员应从症状群的角度出发, 为患者提供有效的症状管理措施, 提高其生活质量。)

Unlike the inverters in the traditional alternating‐current (AC) microgrid, those in a microgrid with series microsource inverters (SMSI‐MG) are connected to the power grid after being cascaded. The authors of this study first divide the control sections according to the degree of grid voltage dips and formulate a coordinated scheme to suppress fluctuations in the output powers of the SMSI‐MG. For the section in which the degree of unbalanced grid voltage dips is relatively low, a current‐limiting strategy that reduces the output power of the SMSI‐MG through the coordinated control of the generator subunits (CCGU) is proposed. More active power can be provided by the SMSI‐MG when the proposed strategy is used, than in the strategy that is based on changing the reference power, and the output reactive power of the SMSI‐MG can be automatically changed with the degrees of dip and unbalance of the grid voltage. The Light Gradient‐Boosting Machine (LightGBM) is used to establish a mapping relationship between the parameters characterizing overcurrent and the reduction quantity in output active power of the SMSI‐MG to implement the CCGU‐based current‐limiting strategy. The complex collaborative control is simplified to improve the low‐voltage ride through (LVRT) capability of the SMSI‐MG. [ABSTRACT FROM AUTHOR]