灌区节水改造对塔里木河流域治理的作用

在对塔里木河“四源一干”及流域大型灌区存在主要问题分析的基础上，探讨了大型灌区建戌节水改造,对工业及城镇生活需水增长、灌溉及周边生态环境用水、流域综合治理和社会经济可持续发展的作用，深入阐明大型灌区续建配套与节水改造对区域水资源合理配置生态及环境发展的重大意义。     

Emerging issues in genomic selection

Genomic selection (GS) is now practiced successfully across many species. However, many questions remain, such as long-term effects, estimations of genomic parameters, robustness of genome-wide association study (GWAS) with small and large datasets, and stability of genomic predictions. This study summarizes presentations from the authors at the 2020 American Society of Animal Science (ASAS) symposium. The focus of many studies until now is on linkage disequilibrium between two loci. Ignoring higher-level equilibrium may lead to phantom dominance and epistasis. The Bulmer effect leads to a reduction of the additive variance; however, the selection for increased recombination rate can release anew genetic variance. With genomic information, estimates of genetic parameters may be biased by genomic preselection, but costs of estimation can increase drastically due to the dense form of the genomic information. To make the computation of estimates feasible, genotypes could be retained only for the most important animals, and methods of estimation should use algorithms that can recognize dense blocks in sparse matrices. GWASs using small genomic datasets frequently find many marker-trait associations, whereas studies using much bigger datasets find only a few. Most of the current tools use very simple models for GWAS, possibly causing artifacts. These models are adequate for large datasets where pseudo-phenotypes such as deregressed proofs indirectly account for important effects for traits of interest. Artifacts arising in GWAS with small datasets can be minimized by using data from all animals (whether genotyped or not), realistic models, and methods that account for population structure. Recent developments permit the computation of P-values from genomic best linear unbiased prediction (GBLUP), where models can be arbitrarily complex but restricted to genotyped animals only, and single-step GBLUP that also uses phenotypes from ungenotyped animals. Stability was an important part of nongenomic evaluations, where genetic predictions were stable in the absence of new data even with low prediction accuracies. Unfortunately, genomic evaluations for such animals change because all animals with genotypes are connected. A top-ranked animal can easily drop in the next evaluation, causing a crisis of confidence in genomic evaluations. While correlations between consecutive genomic evaluations are high, outliers can have differences as high as 1 SD. A solution to fluctuating genomic evaluations is to base selection decisions on groups of animals. Although many issues in GS have been solved, many new issues that require additional research continue to surface.     

CD8+T细胞在不同年龄家兔胃肠道的分布规律

探讨不同年龄组家兔胃肠道各段CD8⁺T细胞的分布特征,为进一步研究CD8⁺T细胞的作用奠定形态学基础。采用免疫组织化学技术对不同年龄组(幼年组、青年组、老年组)家兔胃肠道内CD8⁺T细胞进行染色、观察及统计分析。结果显示,家兔的CD8⁺T细胞多呈圆形、椭圆形或呈不规则形。在不同年龄组家兔,胃肠不同部位的分布有如下特点:家兔的CD8⁺T细胞主要分布于胃肠道的固有层中;青年组CD8⁺T细胞的分布数量显著高于幼年组和老年组;各肠段之间CD8⁺T细胞分布的数量差异不显著,但其分布的总量按照小肠、大肠、胃的顺序依次降低。研究结果显示,CD8⁺T细胞在家兔小肠的分布最多,并且其数量随着年龄的增长呈现先上升后下降的趋势,青年家兔胃肠的分布最为丰富。     

Robust Adaptive Control Based on On-line Identification to Multi-parameters

In system controlled,Sampling these parameters and with parameters for controller in time, it is an object to adaptive control. The article presents a scheme that the structure parameters on it's model and model parameters is robust identified by on line, while to optimal of algorithm on adaptive control is fulfilled. In control scheme, method of intelligent identifying to the structure parameters(levels of model) and algorithm of robust pole placement are introduced also It is advancer for already mentioned scheme. Whole scheme presents new model on adaptive control.     

废弃秸秆生物气化的实验研究

利用微生物对秸秆进行气化实验,研究表明:高浓度的VFA并不能抑制甲烷的生成,只是使甲烷存在一段休眠期。浸泡10天的秸秆,产气峰值出现快;当秸秆浸泡超过20天时,产气慢、周期长。其原因是浸泡期间生成的乙醇需要一段时间向乙酸转化;而驯化污泥做接种物,甲烷菌活性强,产气周期短。     

优质独本菊和多头菊规模化栽培技术试验

以独本菊和多头菊为研究对象,对其进行了育苗和栽培试验。结果表明:间歇式全光雾照扦插出的苗品质好,省时省事,B9和多效唑结合使用矮化效果好,且垄作套盆比平地套盆栽培效果好,有利于规模化生产。     

不同植物生长促进剂对香蕉假植大苗培育的调控作用

采用盆栽试验,在香蕉假植大苗培育过程中分别喷施浓度均为20 mg/L的赤霉素、复硝酚钠、胺鲜酯、α-萘乙酸钠等植物生长促进剂,以喷施清水为对照,通过不同处理假植大苗生长、物质累积及生理指标的分析,明确不同植物生长促进剂在香蕉假植大苗调控的作用。结果表明,本试验采用的4种植物生长促进剂对香蕉假植大苗培育的调控作用不同。与对照相比,叶面分别喷施20mg/L赤霉素、复硝酚钠均能有利于香蕉假植大苗假茎高及叶面积增加,提高叶绿素含量及叶绿素a、b含量,且以上两种植物生长促进剂平均提高叶绿素含量26.46%;喷施20mg/Lα-萘乙酸钠能提高假植苗假茎粗,提高干物质累积量16.11%积及吸氮量9.95%,促进氮磷钾养分吸收。叶面喷施赤霉素、复硝酚钠、α-萘乙酸钠和胺鲜酯均能显著提高香蕉假植大苗抗性,平均降低丙二醛含量14.64%、提高脯氨酸含量64.36%和SOD含量16.74%,且赤霉素还能显著提高POD含量82.13%。     

优质脆李新品种‘中李5号’的选育

‘中李5号’李是以‘青脆李’为母本经自然实生选育而成。该品种生长势较强,树姿半开张;在河南省郑州市观察,3月上旬进入初花期,3月中旬进入盛花期,花期持续约10 d;果实发育期约120 d,于7月中旬成熟;果实近圆形,果顶扁平,缝合线浅,平均单果重46.8 g,果皮呈黄绿色,不着红色,果面有明显果粉层;果肉呈浅黄色,肉质细腻、硬脆,汁液多,纤维少,风味酸甜,无香气;果实可溶性固形物含量15.8%,维生素C含量6.82 mg/100 g,可溶性糖含量9.62%,可滴定酸含量0.82%,可食率97.9%;该品种5年生树的株产可达32 kg以上,丰产能力较强,在河南及周边省市李树适生区均可栽植。