右江流域水生态补偿机制研究初探

为保护右江流域生态环境,协调郁江乃至珠江上下游各方经济利益,更好的激励上游地区生态环境保护行为,通过分析右江流域水生态现状、存在问题、现有生态补偿政策环境及其在郁江流域、珠江流域中的地位和作用,利用外部性理论,分析提出了右江流域水生态补偿模式。通过对标对表有关生态保护规划和区划成果,立足百色市实际,提出了右江流域水生态补偿内容、补偿主客体、补偿标准和补偿方式,初步构建右江流域水生态补偿机制框架,并提出有针对性的补偿政策建议,为水生态补偿实施提供了参考。     

基于部首嵌入和注意力机制的病虫害命名实体识别

为了解决农业病虫害命名实体识别过程中存在的内在语义信息缺失、局部上下文特征易被忽略和捕获长距离依赖能力不足等问题，以农业病虫害文本为研究对象，提出一种基于部首嵌入和注意力机制的农业病虫害命名实体识别模型(Chinese agricultural diseases and pests named entity recognition with joint radical embedding and self attention, RS-ADP)。首先，该模型将部首嵌入集成到字符嵌入中作为输入，用以丰富语义信息。其中，针对部首嵌入设计了3种特征提取策略，即卷积神经网络(Convolutional neural network, CNN)、双向长短时记忆网络(Bidirectional long short term memory network, BiLSTM) 和CNN-BiLSTM；其次，采用多层不同窗口尺寸的CNNs层提取不同尺度的局部上下文信息；然后，在BiLSTM提取全局序列特征的基础上，采用自注意力机制进一步增强模型提取更长距离依赖的能力；最后，采用条件随机场(Conditional random field, CRF)联合识别实体边界和划分实体类别。在包含11个类别和24715条标注样本的农业病虫害自制语料上进行了实验。结果表明，本文模型RS-ADP在该数据集上精确率、召回率和F1值分别为94.16%、94.47%和94.32%；在具体实体类别上，RS-ADP在作物、病害、虫害等易识别实体上F1值高达95.81%、97.76%和97.23%。同时，RS-ADP在草害、病原等难以识别实体上F1值仍保持86%以上。实验结果表明，本文所提模型能够有效识别农业病虫害命名实体，其识别精度优于其他模型，且具有一定的泛化性。     

粪肠球菌生长曲线的测定及其对小鼠脑组织的影响

为测定致羔羊脑炎粪肠球菌（Enterococcus faecalis）的生长曲线，寻求一种快速而准确的方法测定不同生长时期粪肠球菌数量，并客观评价其毒性强弱及其对小鼠脑组织的影响，试验采用平板菌落计数法和OD-Monitor振荡比浊法（D_λ值法）测定粪肠球菌的生长曲线，探究该菌在合适时间段内的吸光值（D_{600 nm}）与平板菌落计数法测定的活菌数（CFU）的关系。用粪肠球菌感染小鼠，观察记录小鼠的死亡情况，最后采用Karber法计算粪肠球菌感染小鼠的半数致死量（LD₅₀）。用LD₅₀的剂量感染小鼠，及时采集死亡小鼠脑组织，未死亡的小鼠72 h后全部剖杀取脑组织，一部分做涂片染色，制作病理切片，观察病理变化；一部分进行培养，用于PCR方法进行细菌的回收鉴定。结果显示，用两种方法测定此株粪肠球菌的生长曲线基本一致，在2~8 h生长迅速，为对数生长期，8~14 h生长缓慢，为稳定期，14 h之后死亡数增加，进入衰亡期；对12 h粪肠球菌D_{600 nm}与CFU的关系进行探讨，成功建立回归方程：y=20.769x-1.3422，R²=0.997；其感染小鼠的LD₅₀为7.77×10¹¹个活菌。以此剂量感染小鼠，脑组织涂片染色和培养染色，均能看到革兰氏阳性球菌；PCR结果显示，均出现了大小为112 bp的条带。对脑组织进行病理学观察发现该菌可导致脑组织充血、出血、形成微血栓，脑膜充血。通过生长曲线和其D_{600 nm}与CFU关系的建立，可实时监测粪肠球菌数量，为后期更深入研究粪肠球菌穿越血脑屏障的机制奠定重要的理论基础。     

低聚半乳糖干预缓解肠道炎症的研究进展

肠道炎症已成为我国社会健康的难题和挑战，其发病率在我国迅速增长。肠道炎症发病原因复杂，目前尚缺乏有效的缓解药物，因此加强肠道炎症有效缓解物质的研发至关重要。低聚半乳糖（galactooligosaccharide，GOS）是一种食疗益生性较优的乳源功能性低聚糖，能够有效促进肠道内益生菌的增殖，改变肠道菌群结构，刺激免疫应答，进而改善肠黏膜屏障功能，缓解肠道炎症。本文综述近年来国内外有关肠道炎症及GOS干预缓解肠道炎症作用的研究进展，并对其应用前景进行展望，为此领域的研究提供科学依据。     

Regulatory role of l-proline in fetal pig growth and intestinal epithelial cell proliferation

l-proline (Pro) is a precursor of ornithine, which is converted into polyamines via ornithine decarboxylase (ODC). Polyamines plays a key role in the proliferation of intestinal epithelial cells. The study investigated the effect of Pro on polyamine metabolism and cell proliferation on porcine enterocytes in vivo and in vitro. Twenty-four Huanjiang mini-pigs were randomly assigned into 1 of 3 groups and fed a basal diet that contained 0.77% alanine (Ala, iso-nitrogenous control), 1% Pro or 1% Pro + 0.0167% α-difluoromethylornithine (DFMO) from d 15 to 70 of gestation. The fetal body weight and number of fetuses per litter were determined, and the small and large intestines were obtained on d 70 ± 1.78 of gestation. The in vitro study was performed in intestinal porcine epithelial (IPEC-J2) cells cultured in Dulbecco''s modified Eagle medium-high glucose (DMEM-H) containing 0 μmol/L Pro, 400 μmol/L Pro, or 400 μmol/L Pro + 10 mmol/L DFMO for 4 d. The results showed that maternal dietary supplementation with 1% Pro increased fetal weight; the protein and DNA concentrations of the fetal small intestine; and mRNA levels for potassium voltage-gated channel, shaker-related subfamily, member 1 (Kv1.1) in the fetal small and large intestines (P < 0.05). Supplementing Pro to either gilts or IPEC-J2 cells increased ODC protein abundances and polyamine concentrations in the fetal intestines and IPEC-J2 cells (P < 0.05). In comparison with the Pro group, the combined administration of Pro and DFMO reduced the expression of ODC protein and spermine concentration in the fetal intestine, as well as the concentrations of putrescine, spermidine and spermine in IPEC-J2 cells (P < 0.05). Meanwhile, the percentage of cells in the S-phase and the mRNA levels of proto-oncogenes c-fos and c-myc were increased in response to Pro supplementation, whereas depletion of cellular polyamines with DFMO increased tumor protein p53 (p53) mRNA levels (P < 0.05). Taken together, dietary supplementation with Pro improved fetal pig growth and intestinal epithelial cell proliferation via enhancing polyamine synthesis.     

1株H1N1亚型猪流感病毒的全基因组特征及其对小鼠的致病性

旨在了解河南省猪流感病毒的流行情况及其遗传进化和基因组特征。2018年4月，从河南省某一出现疑似流感症状猪群中采集鼻拭子样品150份用于分离病毒，对分离病毒的全基因组进行序列测定和分析。同时感染6周龄BALB/c小鼠，研究其对小鼠的致病性。结果显示，获得1株H1N1亚型病毒[命名为A/swine/Henan/NY20/2018（H1N1）]。遗传进化表明，其HA和NA基因属于欧亚类禽H1N1分支，PB2、PB1、PA、NP和M基因属于2009甲型H1N1分支，NS基因属于经典H1N1分支。HA蛋白的裂解位点序列为PSIQSR↓GL，具有低致病性流感病毒的分子特征，在小鼠肺和鼻甲有效复制并能引起肺组织病理学变化。本研究分离到1株3源重排H1N1亚型病毒，对小鼠呈现一定致病力，提示应进一步加强对SIV的监测。     

Identification of an H1N1 subtype of swine influenza virus and serological analysis

To investigate the epizootic of swine influenza virus(SIV), 60 nasal swabs were collected from a clinical cases of pig farm in Tai'an City, Shandong Province of China in April 2017. SIV was isolated by inoculating into 10-day-old Special Pathogen Free embryonated eggs and the whole genome was sequenced. An H1N1 subtype SIV was isolated and designated as A/swine/Shandong/TA04/2017(H1N1). Phylogenetic analysis showed that apart from the polymerase A(PA) fragment belonging to the 2009 pandemic H1N1 branch, seven genome segments belonged to avian-like H1N1 influenza virus lineage. The cleavage site sequence of the hemagglutinin(HA) protein was PSIQSR↓G, which is a typical molecular biological characteristic. Five potential N-glycosylation sites(N14, N26, N277, N484 and N543) were found in the HA gene. To further investigate the epidemiology of SIV in this farm, the 995 serum samples were assessed with EAH1N1 2009 pandemic H1N1 and H3 N2 antigens. The results showed that the total positive rate was 65.43%. The positive rates of single virus infection detected by EAH1N1, 2009 pdmH1N1 and H3 N2 for serum HI(Hemagglutination inhibition) were 48.35, 30.85 and 7.47%, respectively. The results showed that SIV in Shandong Province has been reassorted in some segments and the SIV-positive rate was high on the SIV outbreak farm. These data provide evidence of an epizootic of SIV.     

Kernel vitreousness and protein content: Relationship,interaction and synergistic effects on durum wheat quality

Four sets of durum samples were used in this study to further understand the interrelationships among hard vitreous kernels (HVK), protein content, and pigment concentration, with a focus on the interaction and synergistic effects of protein content and vitreousness on durum quality. HVK level increases with higher protein content in the range of 9.5–12.5%, but this relationship is less evident in durum samples with high protein content (12.5–14.5%). Both protein content and kernel vitreousness can significantly affect durum milling quality. White starchy kernels (WSK) in low protein durum have a very detrimental impact on milling and pasta processing quality, but high protein content can mitigate the adverse impact of WSK on durum quality. Although protein content plays a dominant role, higher HVK might contribute positively to pasta firmness. There was no significant difference in yellow pigment content between HVK and WSK. However, pigment loss from semolina to dough was higher for WSK than HVK. Despite the difference in protein content, HVK and WSK have little difference in gluten strength. The monomeric protein was preferentially accumulated in HVK. The glutenin proteins of HVK and WSK were similar in the ratios of 1Bx/1By and HMW/LMW-GS.     

保护地黄瓜新品种唐杂6 号的选育

唐杂6 号是以雌性系S16 为母本，以自交系S26 为父本配制的强雌型黄瓜一代杂种。生长势强，商品瓜短棒状， 瓜长12～14 cm，横径4.0～4.3 cm，非特异性环境下雌花率95% 以上，瓜皮嫩绿有光泽，白刺，刺瘤稀小，平均单瓜质量 131.8 g 左右，高抗霜霉病，抗细菌性角斑病，耐白粉病；春保护地栽培平均产量可达8 000 kg·（667 m²） ^-1，秋冬保护地栽 培产量可达6 500 kg·（667 m²） ^-1；适合河北、北京、天津及东北地区春、秋保护地种植。