2017年-2019年郑州地区猪圆环病毒3型分子流行病学调查及Cap基因序列分析

为了分析2017年-2019年郑州地区猪场中猪圆环病毒3型(PCV-3)分子流行情况及代表株Cap基因序列遗传情况,采集郑州地区规模化猪场、散养猪场中患病猪的淋巴结、脾脏、肾脏及血清样品1 175份,采用PCR进行PCV3检测,并选择代表株的Cap基因进行PCR检测与分析其遗传变异情况.结果表明,2017年-2019年...     

苗期遮光对易抽薹型大白菜抽薹开花的影响

以易抽薹型大白菜自交不亲和系８７１５８为试材，探讨了苗期遮光对其抽薹开花的影响。结果表明：４叶１心和６叶１心的幼苗的花芽已分化，２叶１心开始遮光处理以每天处理６小时的效果最好，比对照延迟花芽分化７天。遮光处理对易抽薹型大白菜延迟现蕾和抽薹开花有一定的作用，在本试验范围内，开始遮光处理的时间越早，每天遮光处理的时间越长，遮光处理的天数越多，效果越明显     

魔芋不同类型愈伤组织及分化能力研究

以花魔芋球茎和白魔芋幼嫩叶柄为外植体诱导愈伤组织,经过3次或3次以上继代培养,魔芋愈伤组织可形成3种不同类型：A型水渍状,半透明;B型—浅黄色,表面呈球形瘤状突起;C型—绿色或橙红色,结构致密。3种类型的愈伤组织在不同的培养条件下可以相互转变,不同类型的愈伤组织分化能力不同。组织学切片显示了3种类型愈伤组织的细胞类型和组织结构特征。     

Characteristics of Collagen from Rohu (Labeo rohita) Skin

Acid soluble collagen (ASC) and pepsin soluble collagen (PSC) were isolated from rohu skin with the yield of 64.2 and 6.8% (dry weight basis), respectively. Both collagens had glycine as the major amino acid with imino acid content of 196–202 residues/1,000 residues and were characterized as type I collagen with molecular composition of (α1)₂α2-heterotrimer. Fourier transform infrared spectra of both collagens were similar, with no shift in wavenumber of all amide bands. The T_max value of ASC and PSC was 36.40 and 35.48°C, respectively. The zero surface net charge of ASC and PSC was found at pH 5.9 and 5.3, respectively.     

避风型渔港避风因素浅析

我国的东南沿海是最容易遭受热带气旋影响的脆弱地带,每年的5-11月,都会遭受热带气旋的影响,对渔港、渔船和渔民构成严重威胁.而渔港的避风能力是渔民最为关心的问题,通过近几年登陆我国的强台风等级以上的热带气旋对渔港、渔船及渔民造成损失的实例分析,从防波堤设计标准、避风锚地的底质、锚泊方式等3个方面对避风型渔港的避风因素展开讨论,得到了有价值的结论,为渔港、渔船和渔民减少灾害,为政府建设避风型渔港决策提供科学依据.     

辣椒花药颜色突变体Caya表型特征分析及遗传定位

以通过EMS诱变筛选得到的黄色花药辣椒突变体Caya为材料,以野生型樟树港辣椒ST–8为对照,测定花药中花青素及类黄酮的含量,进行花粉活力鉴定,发现突变体Caya花药中花青素含量显著降低,类黄酮含量和花粉活力与ST–8的无显著变化。以ST–8和Caya进行正反交,得到F1群体,F1自交构建F2群体,F1和Caya回交构建BC1群体,调查各群体的紫色花药和黄色花药植株数量,分析花药颜色的遗传规律,发现黄色花药受1对隐性核基因控制;采用BSA–Seq技术对控制花药颜色的基因进行定位,将候选区域锁定在2号染色体142Mbp至157Mbp;设计9对SNP标记对F2分离群体进行基因分型,进一步缩小候选区间,最终将目的基因定位于147 461 604 bp至150 376 942 bp,在候选区间内筛选到2个与花青素合成密切相关的基因,登录号为Capana02g002586、Capana02g002763。     

How do urban forests with different land use histories influence soil organic carbon?

Urban forests play a vital role in building soil organic carbon pools in urban areas. In many cases, urban forests are constructed on land previously used for agriculture, parks, or buildings. However, it is still being determined whether historical land use affects soil organic carbon (SOC) stocks in these forests. In this study, we asked: 1) How are SOC and its labile fractions (LOC) in urban forests affected by historical land use? and 2) How do SOC and LOC vary with time and vegetation type in urban forests built on land with different histories? We collected soil samples at three soil depths, 0–10, 10–20, and 20–30 cm, in 48 evergreen and 77 deciduous forest plots in 77 parks in Beijing, all built within the last 30 years. Plots represent two historical land use types, vegetated or non-vegetated, and three planting time classes, young (5–10 years), intermediate (11–20 years), and old (21–30 years). Our findings showed that there were significant differences between historical land use types in SOC and microbial organic carbon (MBC), this may be due to backfill soil before greening on non-vegetated land. Urban forests that were built on vegetated land accumulated SOC over time, while those on historically non-vegetated land did not. Evergreen forests had greater SOC and LOC than deciduous forests only on historically non-vegetated land. In addition, SOC and LOC were found to be negatively affected by increased soil bulk density. However, soil bulk density was not significantly different between both historical land use types and urban forest types. Overall, our study indicates that if SOC sequestration is a high priority in urban forests, cities could concentrate on more efficient management to increase SOC, such as soil rehabilitation and the use of evergreen tree species.     

节杆式拱泥机器人位置检测设计

拱泥机器人的任务是在沉船打捞时代替潜水员完成水下作业,即攻打千斤洞,并带着千斤缆穿过沉船底部。为此,简要介绍了节杆式水下机器人运动控制中的应用,提出了节杆式拱泥机器人位置检测设计方案,设计了位置检测系统及通讯接口电路,并完成系统的软件设计工作。     

猪圆环病毒2型ORF3基因的克隆及原核表达

以细胞总基因组提取试剂盒抽提PCV2细胞毒株总DNA为模板,用特异性引物扩增PCV2 ORF3基因。将ORF3和表达载体pGEX-6p-1用BamH I和Sal I双酶切回收后连接,将测序验证为阳性的重组质粒命名为pGEX-6p-1-ORF3。重组质粒pGEX-6p-1-ORF3转化BL21(DE3)后用IPTG诱导表达并纯化,对获得的表达产物进行SDS-PAGE电泳、Western blot检测。结果表明:PCV2 ORF3在pGEX-6p-1中获得了高效表达,其表达蛋白主要以包涵体形式存在,其分子质量约为37 kD,且能够和PCV2阳性血清发生特异性相互作用,具有免疫学活性。