19 份彩色小麦种质资源微量营养元素比较分析

彩色小麦因为富含各种微量营养元素而成为解决隐性饥饿的研究热点,为了对彩色小麦种质资源中的微量营养元素进行全面的评价,对来自黄淮麦区的 19 个彩色小麦种质资源和 1 个对照白粒小麦籽粒中的 16 种微量元素进行了检测。结果表明,参试彩色小麦各种微量元素的平均含量顺序为铁 > 锰 > 锌 > 锶 > 铜 > 铬 > 镍 > 钼 > 钛 > 锡 > 砷 > 硒 > 钒 > 钴 > 银 > 镉;19 个彩色小麦籽粒中锰、砷、钛、钴、铜、锶、钼、铬、镉、锡、铁共 11 个微量元素与对照白粒小麦差异显著;大多数紫（黑）粒小麦的微量营养元素都高于蓝粒小麦和白粒小麦,蓝粒小麦的铜、锌、锶、钼、锡含量高于大部分紫（黑）粒小麦和白粒小麦,白粒小麦的钼和锡含量最高;蓝粒小麦砷含量普遍较低;中黑麦 6 号等 11 个彩色小麦种质资源没有检测出镉含量,是宝贵的抗镉金属污染的小麦种质资源。以上结果可以为彩色小麦种质资源微量营养的科学利用和保障人类健康提供理论参考。     

干旱胁迫对北苍术种子萌发及幼苗生理特性的影响

用聚乙二醇（PEG-6000）模拟干旱胁迫,探究其对北苍术种子萌发及幼苗生理特性的影响。分别以 5%、10%、15%、20%、25% 浓度的 PEG-6000 溶液对内蒙古赤峰和河北承德的北苍术种子进行处理,分析种子的萌发时间、发芽势、发芽率、根长、茎长和呼吸速率指标变化;发芽后模拟自然干旱,探究其对幼苗光合速率的影响。结果表明,河北种子的萌发时间比内蒙古种子短;内蒙古种子和河北种子的发芽率随着干旱胁迫的加剧先升高后降低,在 10% 干旱胁迫下,种子的发芽率最高,内蒙古种子为 49.97%,河北种子为 80.00%;在 25% 干旱胁迫下,种子的发芽率最低,内蒙古种子的发芽率为 6.67%,河北种子的发芽率为 31.07%。2 种种子的发芽势、根长、茎长和呼吸速率均随着干旱胁迫的加剧逐渐降低,但整体上河北种子的降低程度小于内蒙古种子。自然干旱胁迫 6d 后,北苍术幼苗的光合速率降低。     

Approaches to Configuration Determinations of Flexible Marine Natural Products: Advances and Prospects

Flexible marine natural products (MNPs), such as eribulin and bryostatin, play an important role in the development of modern marine drugs. However, due to the multiple chiral centers and geometrical uncertainty of flexible systems, configuration determinations of flexible MNPs face great challenges, which, in turn, have led to obstacles in druggability research. To resolve this issue, the comprehensive use of multiple methods is necessary. Additionally, configuration assignment methods, such as X-ray single-crystal diffraction (crystalline derivatives, crystallization chaperones, and crystalline sponges), NMR-based methods (JBCA and Mosher’s method), circular dichroism-based methods (ECCD and ICD), quantum computational chemistry-based methods (NMR calculations, ECD calculations, and VCD calculations), and chemical transformation-based methods should be summarized. This paper reviews the basic principles, characteristics, and applicability of the methods mentioned above as well as application examples to broaden the research and applications of these methods and to provide a reference for the configuration determinations of flexible MNPs.     

饲料分析检验过程的质量保证与控制

在饲料分析检验过程中不可避免产生系统和随机误差,从而影响分析结果的准确度。系统误差是由于检验过程中某些确定的、经常性的原因所造成的误差．它对检验结果的影响比较固定．在重复检验过程中可以重复地表现出来．系统误差产生的原因和来源主要包括仪器误差、试剂误差、测定方法误差、分析人员个人误差等。随机误差是由于一些偶然的外部因素所引起的．产生随机误差的因素不定。     

Taxonomic and Bioactivity Characterizations of Mameliella alba Strain LZ-28 Isolated from Highly Toxic Marine Dinoflagellate Alexandrium catenella LZT09

Microalgae host varied microbial consortium harboring cross-kingdom interactions with fundamental ecological significance in aquatic ecosystems. Revealing the complex biofunctions of the cultivable bacteria of phycosphere microbiota is one vital basis for deeply understanding the mechanisms governing these dynamic associations. In this study, a new light-yellow pigmented bacterial strain LZ-28 was isolated from the highly-toxic and harmful algal bloom-forming dinoflagellate Alexandrium catenella LZT09. Collective phenotypic and genotypic profiles were obtained to confidently identify this strain as a new Mameliella alba member. Comparative genomic analysis showed that strain LZ-28 shared highly similar functional features with other four marine algae-derived M. alba strains in spite of their distinctive isolation sources. Based on the bioactivity assaying, the mutual growth-promoting effects between bacterial strain LZ-28 and algal strain LZT09 were observed. After the culture conditions were optimized, strain LZ-28 demonstrated an extraordinary production ability for its bioflocculanting exopolysaccharides (EPS). Moreover, the portions of two monosaccharides glucose and fucose of the EPS were found to positively contribute to the bioflocculanting capacity. Therefore, the present study sheds light on the similar genomic features among the selected M. alba strains, and it also reveals the potential pharmaceutical, environmental and biotechnological implications of active EPS produced by this new Mameliella alba strain LZ-28 recovered from toxic bloom-forming marine dinoflagellate.     

新型饲料添加剂——碱式氯化锌的合成及性质研究

以氯化锌和氧化锌为原料,合成了一种新型饲料添加剂——碱式氯化锌[Zn5(OH)8Cl2·H2O,TBZC]。采用正交试验法,研究了反应温度、反应时间、反应液pH值、干燥温度对TBZC合成的影响,确定了最佳合成条件:氯化锌和氧化锌摩尔比1:4、反应液pH值5.5、反应温度90℃、反应时间2.5h、干燥温度80℃、干燥时间2h,产率可达88%。借助XRD、IR、DSC确定其结构。通过对TBZC的吸水性、溶解性进行试验,结果表明,TBZC具有不吸湿、不溶于水、易溶于酸性和中性盐溶液的性质。     

Identification of a conservative site in the African swine fever virus p54 protein and its preliminary application in a serological assay

BackgroundASF was first reported in Kenya in 1910 in 1921. In China, ASF spread to 31 provinces including Henan and Jiangsu within six months after it was first reported on August 3, 2018. The epidemic almost affected the whole China, causing direct economic losses of tens of billions of yuan. Cause great loss to our pig industry. As ELISA is cheap and easy to operate, OIE regards it as the preferred serological method for ASF detection. P54 protein has good antigenicity and is an ideal antigen for detection.ObjectiveTo identify a conservative site in the African swine fever virus (ASFV) p54 protein and perform a Cloth-enzyme-linked immunosorbent assay (ELISA) for detecting the ASFV antibody in order to reduce risks posed by using the live virus in diagnostic assays.MethodWe used bioinformatics methods to predict the antigen epitope of the ASFV p54 protein in combination with the antigenic index and artificially synthesized the predicted antigen epitope peptides. Using ASFV-positive serum and specific monoclonal antibodies (mAbs), we performed indirect ELISA and blocking ELISA to verify the immunological properties of the predicted epitope polypeptide.ResultsThe results of our prediction revealed that the possible antigen epitope regions were A23–29, A36–45, A72–94, A114–120, A124–130, and A137–150. The indirect ELISA showed that the peptides A23–29, A36–45, A72–94, A114–120, and A137–150 have good antigenicity. Moreover, the A36–45 polypeptide can react specifically with the mAb secreted by hybridoma cells, and its binding site contains a minimum number of essential amino acids in the sequence 37DIQFINPY44.ConclusionsOur study confirmed a conservative antigenic site in the ASFV p54 protein and its amino acid sequence. A competitive ELISA method for detecting ASFV antibodies was established based on recombinant p54 and matching mAb. Moreover, testing the protein sequence alignment verified that the method can theoretically detect antibodies produced by pigs affected by nearly all ASFVs worldwide.     

浅议施工组织设计与工程造价的关系

工程造价的高低与合理除了与预算知识有关外,很大程度上取决于施工方案的先进与否;同样,工程造价计算准确与否将直接影响施工方案的优选.通过优化施工组织设计与工程造价之间的关系,提出优化施工组织设计、合理确定工程造价的一些具体措施.     

30%乙酰甲胺磷乳油对水稻纵卷叶螟的防治效果与技术

对30%乙酰甲胺磷乳油防治水稻纵卷叶螟(Cnaphalocrocis medinalis)的田间效果进行了试验。结果表明:使用30%乙酰甲胺磷乳油防治水稻纵卷叶螟的杀虫效果均在71.7%以上,保叶效果高达83.8%。