迈腾B8L发动机故障诊断与修复

发动机电控系统诊断与修复是汽车技术国赛考核的重点,也是教学的难点。笔者结合自身参赛经历和发动机电控系统诊断与修复的教学经验,总结迈腾B8L1.4T发动机故障诊断与排除流程,对于教师教学备课和技能竞赛备赛具有参考意义。

非洲猪瘟病毒B602L蛋白的原核表达、纯化及多克隆抗体制备

【目的】非洲猪瘟病毒(African swine fever virus,ASFV)是对生猪养殖业危害极大的一种病原体,B602L蛋白作为其重要的非结构蛋白,是衣壳蛋白p72折叠为正确的三级结构的伴侣分子之一,在病毒组装成二十面体结构的过程中发挥着关键作用。特异性抗体对于抗非洲猪瘟免疫应答机制及血清学检测方法研究具有重要意义,本研究旨在获取ASFV B602L蛋白,并制备抗ASFV B602L蛋白的多克隆抗体,为ASFV B602L蛋白功能研究及相关诊断试剂的研发提供材料。【方法】以ASFV China/2018/AnhuiXCGQ株的B 602 L基因为研究对象,应用生物信息学软件对B602L蛋白的理化性质、信号肽、跨膜结构、抗原性和蛋白结构进行分析后,利用同源重组的方法将其克隆至原核表达载体pET-28a(+)中,转化大肠杆菌BL21(DE3)感受态细胞后经诱导表达获得B602L重组蛋白,利用镍柱亲和层析进行蛋白纯化,通过SDS-PAGE和Western blotting对B602L蛋白纯化效果进行验证。将纯化后的B602L蛋白免疫BALB/c小鼠制备多克隆抗体,通过间接ELISA方法测定多克隆抗体效价,通过Western blotting和Dot blotting检测多克隆抗体特异性。【结果】生物信息学分析表明,B602L蛋白属于稳定性亲水蛋白,无跨膜区和信号肽。二级结构主要含有α-螺旋(54.91%)、延伸链(9.81%)和无规则卷曲(32.08%)。成功构建了ASFV B602L重组质粒,SDS-PAGE和Western blotting结果显示,重组菌pET-28a-B602L-BL21在16℃、0.5 mmol/L IPTG诱导下高效表达,获得的重组蛋白主要表达在BL21菌株上清中,大小约为70 ku,且能与ASFV阳性血清特异性结合。间接ELISA检测结果显示,制备的抗B602L鼠源多克隆抗体效价达1∶409600,Western blotting和Dot blotting试验结果表明,抗B602L鼠源多克隆抗体能够特异性识别B602L蛋白。【结论】原核表达的B602L重组蛋白具有良好的免疫原性,能够与ASFV阳性血清特异性结合,制备的鼠抗ASFV B602L蛋白多克隆抗体具备较好的生物学活性。本试验结果可为进一步研究ASFV B602L蛋白的生物学功能和非洲猪瘟诊断方法的建立提供生物材料和理论支撑。

MyD88L265P及CD79B基因突变对原发性中枢神经系统淋巴瘤预后的影响

目的探究MyD88L265P及CD79B基因突变对原发性中枢神经系统淋巴瘤(PCNSL)患者预后的影响。方法收集2018年8月-2020年11月于兰州大学第二医院经开颅手术或立体定位活检术确诊的18例免疫功能正常(无HIV感染及免疫抑制药服用病史)的PCNSL患者临床资料进行回顾性分析。分别采用实时荧光定量PCR和一代基因测序技术检测18例PCNSL患者肿瘤组织中MyD88L265P和CD79B基因突变情况。针对可能与PCNSL首次无疾病进展生存期(PFS)和总生存期相关的指标行单因素分析,并采用Cox回归进行多因素分析。结果18例PCNSL肿瘤组织MyD88L265P突变率为38.9%,CD79B突变率为33.3%,MyD88L265P/CD79B共突变率为27.8%。单因素分析结果显示,病灶多发、病灶深部受累、肿瘤组织CD79B突变患者的PFS时间更短(P<0.05);多因素分析结果显示,病灶深部受累(HR=0.135,95%CI 0.023~0.799,P<0.05)、肿瘤组织CD79B突变(HR=0.149,95%CI 0.028~0.800,P<0.05)是PCNSL患者预后不良的独立危险因素。结论本组PCNSL患者肿瘤组织MyD88L265P、CD79B突变频率较高,这两种基因突变尤其是CD79B突变可能与PCNSL不良预后相关。

汽油车无法发动综合故障快速诊断研究分析——以大众迈腾B8L为例

本文主要分析汽油发动机作为动力主体的燃油车辆无法发动的具体故障现象以及根据故障现象快速判断故障方向的方法。详细阐述以大众迈腾B8L为例的汽油车无法发动的故障现象与原因以及测量方法,总结了汽油车无法发动故障的快速诊断诀窍。内容包含汽油发动机电控系统的全部内容与要点,汽油车仍旧是社会交通工具的主体,本文仍具有一定的研究价值与意义。

Evaluation of the Potential of Araucaria angustifolia Seeds as Source of Oligosaccharides, Resistant Starch and Growth of Probiotic Bacteria

“Pinhão”, the seed of Araucaria angustifolia, is an important food, being part of the eating habits of Indigenous communities. In this study, we evaluated the oligosaccharide content, resistant starch and the growth of probiotic bacteria. GF4 (1-fructofuranosylnystose) was the main fructo-oligosaccharides found, in higher contents compared to other food sources. Maltooligosaccharides (MOS) represented the main part of the oligosaccharides profile of Brazilian pine seeds. In descending order of importance was maltoheptaose (G7), maltohexose (G6) and maltotriose (G3). The starches from the variety Sanct josephi presented the highest amount of resistant starch that could stimulate probiotic strains, mainly B. breve and L. plantarum, and may have a prebiotic effect, potentially promoting health benefits. This study advances the understanding of the chemical composition of the main portion of the “pinhão” enhancing awareness of its potential as a healthy food source, contributing to different uses and indirectly with the species preservation.

大众迈腾B8L轿车启动系统工作过程与故障诊断分析

以大众迈腾B8L轿车发动机启动系统为例,分析启动系统的工作过程以及当启动系统出现故障时的诊断流程和思路。分析认为,维修人员熟悉该车发动机启动系统的工作过程,能够对启动系统工作条件是否正常进行判断,以及可以熟练掌握该车发动机启动系统的诊断流程。

Rhizobium Inoculation and Micronutrient Addition Influence the Growth,Yield,Quality and Nutrient Uptake of Garden Peas(Pisum sativum L.)

Garden pea productivity and qualities are hampered in zinc(Zn),boron(B),and molybdenum(Mo)deficient soil.Thus,the combination of micronutrients(i.e.,Zn,B,and Mo)and rhizobium is necessary to increase the productivity and quality of garden peas,since this management for garden peas is neglected in Bangladesh.Therefore,the present study was made to assess the effectiveness of rhizobium inoculant singly or in combination with the micronutrients(i.e.,Zn,B,and Mo)on growth,yield,nutrient uptake,and quality of garden peas.Treatments were:T_(1)=Control,T_(2)=Rhizobium inoculation at 50 g/kg seed,T_(3)=T_(2)+Zn_(3)Mo1,T_(4)=T_(2)+B_(2)Mo1,T_(5)=T_(2)+Zn_(3)B_(2),T_(6)=T_(2)+Zn_(3)B_(2)Mo1 and T_(7)=Zn_(3)B_(2)Mo1.All treatments were arranged in a randomized complete block design and repeated all treatments in three times.The application of 3 kg Zn,2 kg B,and 1 kg Mo ha^(−1)with inoculation of Rhizobium at 50 g kg^(−1)seed(T_(6))facilitated to increase of 44.8%in the green pod and 29.7%seed yield over control.The same treatment contributed to attaining the maximum nodulation(25.3 plant^(−1)),Vitamin C(43.5 mg 100 g^(−1)),protein content(22.2%),and nutrient uptake as well as accumulation in garden peas.Among all treatment combinations,treatment T_(6)was found superior to others based on microbial activities,soil fertility,and profitability.The results of the study found that the application of 3 kg Zn,2 kg B,and 1 kg Mo ha^(−1)in combination with Rhizobium inoculation(50 g kg^(−1)seed)can improve the yield and quality of garden peas.The results of the study have the potential for the areas,where there is no use of Rhizobium inoculant or Zn,B,and Mo fertilizer for cultivation of garden pea.

迈腾B8L发动机无法启动故障诊断与排除

以高职国赛“汽车故障检修”选用的迈腾B8L为对象,诊断与排除电气系统的典型部件损坏造成发动机无法启动的故障。首先,描述了发动机无法启动的故障现象:全车不上电、起动机无法运转及起动机运转不着车等;其次,介绍迈腾B8L的启动策略:整车上电策略及起动机运转策略;再次,选取点火开关损坏造成的不上电故障,动力总线损坏造成的起动机不运转故障,起动继电器及其线路损坏造成的起动机不运转故障,曲轴位置传感器及其线路损坏造成的不着车故障;最后,对点火开关、动力总线、启动继电器及其线路、曲轴位置传感器及其线路的故障进行了诊断与排除。在不使用故障诊断仪的前提下,为以上四大部件损坏造成的发动机无法启动故障,提供了系统、全面、有效的排除方法,也为诊断与排除其他部件的故障提供了详细的参考依据。

Stochastic modeling and analysis of hepatitis and tuberculosis co-infection dynamics

Several mathematical models have been developed to investigate the dynamics of tuberculosis(TB)and hepatitis B virus(HBV).Numerous current models for TB,HBV,and their co-dynamics fall short in capturing the important and practical aspect of unpredictability.It is crucial to take into account a stochastic co-infection HBV–TB epidemic model since different random elements have a substantial impact on the overall dynamics of these diseases.We provide a novel stochastic co-model for TB and HBV in this study,and we establish criteria on the uniqueness and existence of a nonnegative global solution.We also looked at the persistence of the infections as long its dynamics are governable by the proposed model.To verify the theoretical conclusions,numerical simulations are presented keeping in view the associated analytical results.The infections are found to finally die out and go extinct with certainty when L´evy intensities surpass the specified thresholds and the related stochastic thresholds fall below unity.The findings also demonstrate the impact of noise on the decline in the co-circulation of HBV and TB in a given population.Our results provide insights into effective intervention strategies,ultimately aiming to improve the management and control of TB and HBV co-infections.

Bioactive chemical constituents from the marine-derived fungus Cladosporium sp.DLT-5

A new isochromanone,cladosporinisochromanone(1),accompanied by 15 known compounds(2–16)were obtained from secondary metabolites produced by marine-derived fungus Cladosporium sp.DLT-5.NMR and HRESIMS spectra elucidation determined the planar structure of 1.Subsequent electronic circular dichroism(ECD)experiment assigned the absolute configuration of 1.Compounds 1,2,4–6,and 10 displayed different degrees of neuroprotective activities on human neuroblastoma cells SH-SY5Y.Five compounds(1,3–5,and 13)emerged resistance to protein tyrosine phosphatase 1B(PTP1B),further kinetic analysis and molecular docking study indicated that the most potent compound 13(IC50value of 10.74±0.61μmol/L)was found as a noncompetitive inhibitor for PTP1B.Surface plasmon resonance(SPR)and molecular docking studies also demonstrated the interaction between compound 12 and Niemann-Pick C1 Like 1(NPC1L1),which has been identified as significant therapeutic target for hypercholesteremia.In addition,compounds 3,6,and 14 showed attractive inhibitory activity against the phytopathogenic fungi:Colletotrichum capsici.Therefore,library of Cladosporium metabolites is enriched and new active uses of known compounds are explored.

马头山羊羊口疮病毒的分离鉴定及其B2L基因的特征分析

为确定湖北省某马头山羊养殖场发生的疑似羊口疮(Orf)的病原及其分子生物学特征。本试验利用牛睾丸细胞对马头山羊唇部痂皮病料进行病毒分离培养,通过细胞病变观察、病毒滴度测定、PCR扩增和测序等方法对分离毒株进行了鉴定。并采用MegAlign、MEGA 7.0、DNAMAN和Bioedit等软件分析了分离毒株和China Vaccine毒株B2L基因的核苷酸序列相似性,并预测了蛋白二级结构和疏水性。结果显示,接种病料上清液的牛睾丸细胞盲传5代后出现细胞病变,经PCR扩增的分离毒株B2L基因大小为1137 bp;所分离羊口疮病毒(ORFV)病毒滴度可达105.5TCID50/mL;分离毒株与AH1404、FJ-YX和GX-BH毒株B2L基因同源性为99.3%;与China Vaccine毒株同源性为89.5%。分离毒株与China Vaccine毒株B2L基因序列分析显示处在不同分支,两者存在8个位点突变(aa11、aa80、aa101、aa123、aa126、aa294、aa327和aa333);B2L蛋白为稳定的疏水性蛋白;分离毒株和China Vaccine毒株的蛋白二级结构存在差异。结果表明,该养殖场ORFV的B2L基因出现变异,有关部门应当加强对ORFV流行情况的监测。

Crocus sativus L.produces anti-inflammatory effects and regulates the NLRP3–NF-κB pathway

Objective:This study aimed to evaluate the anti-inflammatory effects of petal and stamen extracts of saffron crocus(Crocus sativus)and explore the underlying mechanism.Methods:Local and systemic inflammation models were used to investigate the anti-inflammatory effects of C.sativus.A xyleneinduced inflammation model or lipopolysaccharide(LPS)-induced inflammation model was used in this study.C.sativus petal and stamen extracts were each administered to the mice in the xylene and LPS models by gavage for 14 d at 0.1 and 0.4 g/kg doses,respectively.Enzyme-linked immunosorbent assay(ELISA)was used to measure the concentrations of tumor necrosis factor(TNF)-αand interleukin(IL)-1βin mouse serum.Hematoxylin and eosin(H&E)staining was used to observe the pathological changes in the ear in the xylene-induced inflammation model and in the spleen in the LPS-induced inflammation model.NOD-like receptor thermal protein domain associated protein 3(NLRP3)protein levels within the nuclear factor-kappa B(NF-κB)pathway were assessed using western blotting.RAW264.7 cells were treated with LPS(5μg/mL)and LPS+C.sativus(0.05,0.1,and 0.2 mg/mL)for 24 h,and a Cell Counting Kit-8 was used to measure cell proliferation.Changes in NLRP3 and NF-κB levels were evaluated by western blotting.Results:Petal and stamen extracts of C.sativus attenuated the anti-inflammatory effects in local or systemic inflammatory models and repaired pathological changes in the ear in the xylene-induced inflammation model and spleen in the LPS-induced inflammation model.These extracts also decreased the concentrations of TNF-αand IL-1βin the mouse serum in the LPS-induced inflammation model.C.sativus downregulated NLRP3 protein level through the NF-κB pathway and downregulated LC-3 and BECLIN1 in vivo and in vitro.Carbonyl Cyanide3-ChloroPhenylhydrazone(CCCP)weakened the effects of C.sativus on the NLRP3–NF-κB pathway.Conclusion:C.sativus has anti-inflammatory effects and regulates the NLRP3-NF-κB pathway.

2020款迈腾B8L发动机无法启动故障检修

一辆2020款迈腾B8L轿车,按启动按钮,仪表正常点亮;踩刹车同时按启动按钮,启动机有吸合声音但无法转动,无着车迹象。针对该故障现象,根据故障产生机理,依次对该车发动机启动系统的相关部件及其电路等进行了检测诊断。最终排查出的故障原因是,发动机控制单元J623的P/N挡信号线与启动反馈信号线短路,对其进行修复后,发动机可正常启动,车辆故障排除。

弥漫大B细胞淋巴瘤中MYD88、NAP1L5基因特征与临床特征及预后的关系

目的 探讨弥漫性大B细胞淋巴瘤(Diffuse Large B-cell Lymphoma, DLBCL)中MYD88和NAP1L5基因的特征,及其与临床表现和预后之间的关系。方法 分析本院2019年1月至2022年12月期间的87例DLBCL患者中MYD88和NAP1L5基因突变的情况,并分析其与临床特征的关系。评估影响DLBCL患者总生存期的相关因素。结果 87例患者中,31例出现MYD88基因异常,35例出现NAP1L5基因异常。两个基因共异常率为26.43%。MYD88和NAP1L5基因异常及共异常主要集中在ABC型DLBCL中,阳性率分别达74.19%、74.28%、73.91%。在Ⅲ~Ⅳ期病例中,MYD88基因异常和两基因共异常的比例(61.29%、65.21%)均高于I~II期的病例(P<0.05)。在IPI指数为3~5的病例中,MYD88基因异常的比例(64.51%)高于IPI指数为0~2的病例(P<0.05)。生存时间的单因素分析显示,病理分型、临床分期、MYD88、NAP1L5基因异常组和两基因共异常是影响因素。生存分析显示,不同病理分型、临床分期、MYD88基因状态、NAP1L5基因状态、MYD88、NAP1L5基因共异常情况患者的生存时间差异显著(P<0.05)。临床分期、MYD88和NAP1L5基因共异常是影响患者总生存期的独立因素(P<0.05)。结论 MYD88、NAP1L5基因异常与DLBCL的临床特征密切相关,临床分期和MYD88和NAP1L5基因的共异常是影响DLBCL患者总生存期的独立因素。

Analysis of the Clinical Value of Baogan Lishui Decoction and Conventional Western Medicine in Treating Hepatitis B Cirrhosis Refractory Ascites

The objective of this study was to investigate the clinical effect of combination treatment of Chinese medicine Baogan Lishui decoction and western medicine on hepatitis B(Hep B)cirrhosis-related refractory ascites.The control group was given conventional western medicine therapy while the observation group was given same conventional western medicine therapy with additional of Chinese medicine Baogan Lishui decoction.The total effective of clinical treatment on Hep B cirrhosis-related refractory ascites in observation group was higher than that of the control group which was 88.89%compared to 71.11%,respectively,and it was significant different(P<0.05).The combination treatment of Chinese medicine Baogan Lishui decoction and conventional western medicine can significantly increase the treatment effect on Hep B cirrhosis refractory ascites,and thus increases the quality and safety of life.

The system of L-band 2 × 10 Gb/s WDM transmission over conventional single mode fibre with 600 km by chirped fibre Bragg gratings dispersion compensation

A chirped fibre Bragg grating according to ITU-T suggested L-band （2nd channel λ1 = 1570.83 nm; 80th channel λ2 = 1603.57 nm） with more than 1800 ps/nm single channel dispersion compensation is presented in this paper, of which the cladding mode loss, the delay curve ripple and the power fluctuation of the reflected spectrum are less than 0.5 dB, 50 ps and 0.25 dB, respectively. With this new FBG as dispersion compensation device, a 2 × 10 Gb/s wavelength division multiplexing （WDM） L-band transmission of 600 km based on conventional single mode fibre （G.652 fibre） is performed without forward error correction. The bit error rate （BER） is less than 10-12 and the power penalties of the 2nd and 80th channel of L-band are 1.8 dB and 2.0 dB, respectively.

腌干鲢鱼组织蛋白酶B、L活力变化的响应面法预测研究

以鲢鱼为原料,进行腌制和热泵干燥加工,研究内源组织蛋白酶B、L活性在加工过程中的变化。选取加工过程对鲢鱼(Hypophthalmichthys molitrix)组织蛋白酶B、L活力影响较大的3个工艺参数(温度、pH值、盐质量分数)作为试验因素,并根据酶学特性和干燥过程中各理化指标的测定结果确定其试验水平。采用响应面法考察此3因素对组织蛋白酶B、L活性的影响,并根据回归方程对腊干鲢鱼加工过程中的组织蛋白酶活力进行预测。结果表明:回归方程可用于组织蛋白酶B、L实际活力预测;两种酶的潜在活力在加工过程中均呈下降趋势,加工结束时组织蛋白酶B和L的潜在酶活力分别为初始的43.18%和26.08%;通过回归方程对组织蛋白酶B、L在腌制前、腌制后、干燥2d、干燥5d、干燥7d实际活力进行预测,组织蛋白酶B实际酶活力分别为潜在酶活力的36.7%、39.9%、46.5%、46.5%和53.5%,而组织蛋白酶L则为6.6%、5.6%、10.4%、10%和12.6%。

羊口疮病毒F1L和B2L基因真核表达质粒构建及其在MDBK细胞中的表达

目的为构建羊口疮病毒F1L和B2L基因真核表达质粒,同时验证其在MDBK细胞中的表达。方法本试验以pVAX1为真核表达载体,在前期构建的克隆质粒pMD18-T-B2L和pMD18-T-F1L基础上,构建真核表达质粒pVAX1-F1L和pVAX1-B2L,对其分别进行双酶切和测序鉴定,将鉴定正确的真核表达质粒pVAX1-F1L和pVAX1-B2L转染至MDBK细胞,采用RT-PCR和间接免疫荧光试验(IFA)检测目的基因表达。结果双酶切鉴定和序列测定表明真核表达质粒pVAX1-F1L和pVAX1-B2L构建成功,RT-PCR和IFA同时验证目的基因在MDBK细胞浆中能瞬时表达。结论本试验构建成功的真核表达质粒为下一步羊口疮病毒核酸疫苗研究奠定基础。

基于L*a*b*彩色空间和局域动态阈值的药用植物叶片图像分割

叶片图像分割是自动化分类的先决步骤。提出一种基于L*a*b*彩色空间和局域动态阈值的叶片图像分割方法。该方法首先把叶片的RGB图像转换为L*a*b*图像;然后针对b*通道图像,估算出目标叶片所在的局部矩形范围;在此范围内,统计获得像素值分布直方图;最后利用最大类间方差阈值分割法,先算出局部矩形范围内的阈值继而进行全图的分割。实验结果表明:该方法对已采集的叶片图像,包括颜色偏暗的叶片的图像,均具有良好的分割效果。由于锁定目标叶片所处的局部矩形范围,找到了适应于目标叶片分割的阈值,从而更好地实现了南天竺等叶片图像的分割。此外,分割过程不包含数学形态学的开闭运算,使得叶片边缘的细节得以完整保留。

金黄色葡萄球菌L型产B型肠毒素及其基因的研究

目的 :探讨金黄色葡萄球菌 (金葡菌 )L型肠毒素B的产生量及其基因存在情况。方法 :将金葡菌诱导成稳定L型后 ,用ELISA法检测葡萄球菌肠毒素B(SEB) ,用PCR法检测SEB基因。结果 :金葡菌L型SEB的产生量与原菌比差别无显著性 (P >0 .0 5 ) ,PCR发现 4 78bp的阳性条带。结论 :金葡菌变异为L型后SEB产生量不变 ,其基因也未丢失。