微粒捕集器再生背压阈值MAP图建立及其应用

为获得柴油机微粒捕集器（diesel particulate filter,DPF）再生背压阈值以提供再生时机判断基准,针对该文设计的喷油助燃再生系统,提出以总油耗量法为基础DPF再生时机背压判断法。基于AVL-BOOST平台建立装有 DPF 发动机的仿真模型,并试验验证其油耗、功率、转矩、排气温度及 DPF 背压变化模拟值,对比结果表明,该模型具有较好的实用性,为获得较高密度和精度的测点值创造条件。沿发动机纵、横向工况分布面上采用最小二乘拟合法与区间分段线性插值法,借助MATLAB对装有干净DPF的发动机等油耗曲面进行拟合。通过设置仿真模型中DPF模块微粒层厚度,记录各工况油耗,并从中筛选出较干净过滤体发动机油耗超过5%时所对应的DPF背压值作为背压阈值,进一步建立DPF再生背压阈值脉谱图（map of arterial pressure, MAP）。从应用试验来看,相同控制策略下采用该MAP判断再生时机可保证DPF再生过程在5～10 min内完成,过滤体内峰值温度及最大温度梯度均低于安全阈值1400 K、75 K/cm,表明该MAP具有较好的实用性,这为实现微粒捕集器的快速、安全再生提供了依据和技术参考。     

冬枣自发气调(MAP)贮藏技术研究

应用不同类型和不同规格塑料保鲜材料,采用不同包装方式,对冬枣进行自发气调(MAP)试验,试验选出了冬枣适宜的塑料保鲜材料和包装方式分别为;0．02mm聚氯乙烯打18扎和0．02mm聚氯乙烯打12扎。     

MAP3K5基因在畜禽剩余采食量表型调控中的研究进展

随着分子遗传学的发展,已经鉴定出了影响剩余采食量(RFI)的大量数量性状位点和候选基因。有丝分裂原活化蛋白3激酶5(MAP3K5),也称凋亡信号调节激酶1(ASK1),属于MAPK超家族基因之一。目前,已有细胞外信号调节蛋白激酶(ERK)、c-Jun N-末端激酶(JNK)和p38丝裂原激活蛋白激酶(p38-MAPK)这3个MAPK家族成员在哺乳动物细胞中被克隆和鉴定,其主要作用机制是介导3条MAPKs信号通路,从而影响家畜的生长、体型及产奶性状等。课题组在前期对RFI的研究中筛选出与牛剩余采食量相关的MAP3K5基因,但其功能作用尚不明确,笔者在此基础上回顾了该基因的结构、生物学功能,概述了该基因在主要畜禽采食量变异及人类肥胖表型中的功能及作用,并从遗传学的角度重点分析了MAP3K5基因在畜禽RFI表型调控中的可能机制。通过对MAP3K5基因在畜禽RFI表型调控中的研究进展进行综述,期望为后期深入开展MAP3K5基因在畜禽采食量性状调控中的分子机制研究提供思路;对于其他可能通过MAP3K5基因影响畜禽表型的因素(如肠道菌群)有待进一步探讨。     

不同气调包装对鲜食冬枣保鲜效果的比较

[目的]探究自发气调包装保鲜对鲜食的冬枣(果皮转红面积超过2/3)的保鲜效果.[方法]采用两种类型自发气调包装袋MP20(20μm)和MP30(30 m)对冬枣进行包装处理,以微孔包装的冬枣作对照,研究在两种贮藏温度下(25℃和0℃)不同包装条件下冬枣的生理活性及营养成分的变化规律.[结果]冬枣在常温(25℃)贮藏15...     

苦瓜MAP30基因的克隆与载体构建

首先提取苦瓜的基因组DNA,然后根据Genbank中已公开发表的MAP30序列,设计一对特异引物MAP301,MAP302,并增添特异定位于内质网的小肽Kozak序列。采用PCR技术,从苦瓜的基因组DNA中扩增出一分子量为800bp左右的片段,回收克隆测序,结果表明,克隆获得片段与已公开发表的MAP30序列同源性达100%,将阳性克隆进行酶切,获得的目标片段与用同样酶切所获得的植物表达载体pEV1和pEV2大片段连接,酶切鉴定重组子构建成特异表达于果实的载体。     

MAP贮藏对甜樱桃品质的影响

对甜樱桃的贮藏保鲜试验表明,MAP与专用保鲜剂结合可有效地保持果实的鲜食品质,减少果实的腐烂和褐变,降低果实的呼吸强度,延长果实的贮藏期.‘红灯‘甜樱桃贮藏保鲜80 d果实的腐烂率为3.62%;对照果实只贮藏了40 d.‘雷尼‘甜樱桃贮藏保鲜110 d果实的腐烂率为2.1%,褐变率为0,果柄抽干率为0.32%;对照果实只贮藏了50 d.     

1-O-Alkylglycerol Ethers from the Marine Sponge Guitarra abbotti and Their Cytotoxic Activity

The cytotoxicity-bioassay-guided fractionation of the ethanol extract from the marine sponge Guitarra abbotti, whose 1-O-alkyl-sn-glycerol ethers (AGEs) have not been investigated so far, led to the isolation of a complex lipid fraction containing, along with previously known compounds, six new lipids of the AGE type. The composition of the AGE fraction as well as the structures of 6 new and 22 previously known compounds were established using ¹H and ¹³C NMR, GC/MS, and chemical conversion methods. The new AGEs were identified as: 1-O-(Z-docos-15-enyl)-sn-glycerol (1), 1-O-(Z-docos-17-enyl)-sn-glycerol (2), 1-O-(Z-tricos-15-enyl)-sn-glycerol (3), 1-O-(Z-tricos-16-enyl)-sn-glycerol (4), 1-O-(Z-tricos-17-enyl)-sn-glycerol (5), and 1-O-(Z-tetracos-15-enyl)-sn-glycerol (6). The isolated AGEs show weak cytotoxic activity in THP-1, HL-60, HeLa, DLD-1, SNU C4, SK-MEL-28, and MDA-MB-231 human cancer cells. A further cytotoxicity analysis in JB6 P⁺ Cl41 cells bearing mutated MAP kinase genes revealed that ERK2 and JNK1 play a cytoprotective role in the cellular response to the AGE-induced cytotoxic effects.     

Cloning and Bioinformatics Analysis of MAP3K5 Gene CDS Sequence in Pig

In this study,we cloned MAP3K5 gene cDNA sequence,compared the sequence of MAP3K5 with MAP3K families in pig and other species,and studied their conservative structure domain.Obtained the full-length of MAP3K5 gene (5 452 bp) by RACE-PCR,predicted the open reading frame (ORF) and amino acid (AA) sequence,and obtained the information of 31 exons.The low similarity were found in mRNA and amino acid sequences of MAP3K families in pig (<50%).And MAP3K5 had the comparatively high similarity with MAP3K6 in pig.The comparative analyzed the mRNA and protein sequence of pig MAP3K5 gene with other species MAP3K5 gene,founded that the ten species of MAP3K5 mRNA and protein sequence had the high similarity (>78%),and pig MAP3K5 had the comparatively high similarity with Bos taurus,Ovis aries,Canis lupus and Homo sapiens.Function domain analyzed the high similarity protein with MAP3K5 in pig,this research found that pig MAP3K6 protein had the similar conserved function domain with pig MAP3K5.However,the other pig MAP3K families didn't have the similar conserved function domain with pig MAP3K5.The ten species of MAP3K5 protein had the similar conserved function domain.The results obtained the sequence and molecular structure of MAP3K5 gene,and provided an important foundation for further function research of MAP3K5 gene in pig.     

Association Analysis on MAP3K5 Gene Polymorphism Site with Growth and Feed Efficiency Related Traits in Duroc Pigs

This study was aimed to analyze the association of four SNPs of MAP3K5 gene with growth and feed efficiency related traits in Duroc populations. Four SNPs(Ssc1:30769583 A>C;Ssc1:30781169 A>G;Ssc1:30940839 A>G;Ssc1:30962276 G>A)of MAP3K5 gene in Duroc populations were obtained by porcine SNP60 BeadChip（Illumina). The genotype frequency and allele frequency of four SNPs of MAP3K5 gene were analyzed,the result showed that four SNPs were the low-moderate mutation SNPs.The polymorphism of MAP3K5 gene and its association with feed efficiency related traits in Duroc population were analyzed. The results indicated that CC genotype individuals in Ssc1:30769583 A>C had significant lower RFI（133.08 g/d）than AA genotype individuals（P<0.05);GG genotype individuals in Ssc1:30781169 A>G had significant lower RFI（116.18 g/d）and ADFI（0.23 kg/d）than AG genotype individuals（P<0.05);GG genotype individuals in Ssc1:30940839 A>G had significant lower FCR（0.10%）than AG genotype individuals（P<0.05);AA genotype individual in Ssc1:30962276 G>A had significant lower ADG（0.04 kg/d）than GG genotype individuals（P<0.05). All in all,the results suggested that four SNPs polymorphisms of MAP3K5 gene had the significant impact on RFI, ADFI, FCR and ADG traits in Duroc pigs.