一种自适应的网络拓扑自动发现算法

针对现有网络拓扑发现算法的不足，提出并实现了一种自适应网络拓扑自动发现算法——RANTAD(Robust and Adaptive Network Topology Auto Discovery)。BANTAD算法以TCP／IP网络管理体系结构为依托，将现有的各协议和发现技术进行有机地整合，在发现过程的每个阶段，能根据网络的实际情况对所采用的协议和技术进行自适应调整。模拟实验表明RANTAD算法能快速有效地自动发现网络拓扑信息，并且具有很好的健壮性。     

美丽乡村建设生态工程的关键技术探讨

我国美丽乡村生态建设起步较晚,但发展快,势头猛。全国各地展开美丽乡村建设多年,各省市地区已建成一批美丽乡村建设、生态旅游产业好典型范例。虽然取得了一定的成就,但在美丽乡村建设过程中,依然存在不少问题。该研究从前期规划设计、水土保持及水源保护、田园土壤肥力管控和美丽乡村产业发展4个方面介绍了美丽乡村建设生态工程技术实践途径,以期为我国美丽乡村建设生态工程提供可借鉴技术依据。     

Comparative pharmacokinetics of florfenicol in healthy and Pasteurella multocida‐infected Gaoyou ducks

Pasteurella multocida is the causative agent of fowl cholera, and florfenicol (FF) has potent antibacterial activity against P. multocida and is widely used in the poultry industry. In this study, we established a P. multocida infection model in ducks and studied the pharmacokinetics of FF in serum and lung tissues after oral administration of 30 mg/kg bodyweight. The maximum concentrations reached (C_max) were lower in infected ducks (13.88 ± 2.70 μg/ml) vs. healthy control animals (17.86 ± 1.57 μg/ml). In contrast, the mean residence time (MRT: 2.35 ± 0.13 vs. 2.27 ± 0.18 hr) and elimination half‐life (T_½β: 1.63 ± 0.08 vs. 1.57 ± 0.12 hr) were similar for healthy and diseased animals, respectively. As a result, the area under the concentration curve for 0–12 hr (AUC_0–12 hr) for FF in healthy ducks was significantly greater than that in infected ducks (49.47 ± 5.31 vs. 34.52 ± 8.29 μg hr/ml). The pharmacokinetic differences of FF in lung tissues between the two groups correlated with the serum pharmacokinetic differences. The C_max and AUC_0–12 hr values of lung tissue in healthy ducks were higher than those in diseased ducks. The concentration of FF in lung tissues was approximately 1.2‐fold higher than that in serum both in infected and healthy ducks indicating that FF is effective in treating respiratory tract infections in ducks.     

降低苹果梨组培过程中外植体褐化的研究

为克服苹果梨组织培养过程中外植体的褐变现象,提高试验材料的成活率,试验以苹果梨1 a生营养枝嫩梢为试材,通过不同培养基配方、不同药剂处理及水培处理,探讨降低苹果梨外植体褐变的影响因素.结果表明:1/3 MS培养基中的外植体成活率较高;液体培养基较固体培养基对降低外植体的褐变的效果好;水培处理可有效降低外植体的褐变率;生长季节取材,随外植体木质化程度的加深,随水培期的延长,外植体的褐变率呈现先降低后上升的趋势,水培4 d 处理的外植体成活率最高;最佳取材时期为盛花后期,将材料水培6 d,在1/3 MS 6-BA 1.0 mg/L IBA 0.2 mg/L Vc 75 mg/L中获得83.3%的外植体成活率.     

“牧草与草坪草育种学”课程建设与实践

"牧草与草坪草育种学"为草业科学专业的核心课。为了适应草业科学的发展要求,培养具有实践能力和创新精神的草业专业技术人才,宁夏大学草业科学专业对"牧草与草坪草育种学"课程在理论教学、实践教学以及课程考核体系方面进行了改革。教学实践证明,课程改革突出了学生在学习中的主体地位,增强了学生的实践能力,提高了学生学习的主动性和教学质量,促使牧草与草坪草育种学课程建设向高水平方向迈进。     

乡村振兴背景下农业现代化愿景与实现途径

随着我国农业现代化建设的不断深入,农业现代化的基本内涵越发丰富、目标指向越发鲜明、建设思路越发明晰。在乡村振兴背景下,推动农业现代化建设,有助于改善农业生产结构,优化农业生产经营模式,实现农民收入稳定增长,促成绿色生态农业建设,早日实现全面现代化及共同富裕的目标。本文基于乡村振兴背景,在阐述农业现代化基本内涵的基础上,分析我国农业现代化的愿景与实现路径,以期对我国农业现代化建设有所帮助。     

Development of multiplex polymerase chain reaction assays for detecting enterotoxigenic Escherichia coli and their application to field isolates from piglets with diarrhea.

Fimbriae and enterotoxins are major virulence factors associated with enterotoxigenic Escherichia coli (ETEC). In this study, 3 sets of multiplex polymerase chain reaction (mPCR) assays targeting fimbriae, enterotoxins, and other adherence factors were developed for detecting ETEC. A total number of 188 E. coli field isolates were examined, and percentages of E. coli strains carrying each virulence factors were as follows: F4 (7.45%), F5 (29.79%), F6 (6.38%), F18 (15.43%), F41 (3.72%), STa (10.11%), STb (20.74%), LT (9.57%), Stx2e (2.13%), EAST1 (42.02%), F1 (67.55%), AIDA-I (2.66%), and pAA (7.45%). Of the 188 E. coli field isolates examined, 25.53% were found to be pathogenic ETEC, having both fimbriae and enterotoxins. However, the ratio increased to 44.68% when the presence of other adhesins was considered as criteria for virulence. Among the adherence factors, F1 was found to be the most prevalent. AIDA-I and pAA were also found with similar ratio as compared with other virulence factors. In addition, virulence patterns carrying these alternate adhesive genes with enterotoxins were detected with significant ratio. Therefore, it is desirable that alternate adhesins be considered as markers for diagnosis of ETEC.     

几种抗球虫药物对獭兔球虫感染和幼兔生长性能的影响

在福建省福安市某獭兔场共检测出16种艾美耳球虫,均为混合感染。选取210只断乳1周、球虫卵囊阳性的獭兔幼兔,随机分为7组,进行抗球虫药物试验。在抗球虫药物试验组中,2.5%妥曲珠利组的獭兔幼兔按有效剂量30 mg/kg体重、5%肠球双效(盐酸氨丙啉+胺喹噁啉钠)组和5%优球乐(癸氧喹酯)组按有效剂量50 mg/kg体重灌服,分为1次用药组和2次用药组;对照组灌服等量生理盐水。结果显示,妥曲珠利组獭兔幼兔用药后第1周,粪便中的球虫卵囊数(OPG值)比用药前减少78.39%,也显著低于其他药物组和对照组(P<0.01);用药后第2周,球虫OPG值比用药前减少88.35%,感染率也降至最低;用药后第8周,粪便中球虫OPG值比用药前减少92.99%。至用药后第8周,各试验组与对照组獭兔幼兔球虫OPG值均转归为相对较低水平,感染率则仍保持较高水平;妥曲珠利组獭兔幼兔死亡率显著低于对照组(P<0.05),其他组间死亡率差异不显著;其平均增重显著高于对照组(P<0.05),料重比则显著低于对照组(P<0.05)、极显著低于5%肠球双效1次用药组(P<0.01)。     

Parthenolide enhances the apoptosis induced by 4-hydroxyphenyl-retinamide in human hepatoma cells

AIM:To detect the signal pathway of apoptosis induced by 4-hydroxyphenyl-retinamide (4-HPR) and the biological effect of parthenolide-induced apoptosis. METHODS:TUNEL staining, FCM analysis, electrophoretic mobile shift assay (EMSA) were used to determine the actual effects and its mechanism of parthenolide on the 4-HPR-induced apoptosis in human hepatoma Hep-3B and SK-Hep-1 cells. RESULTS:The results of TUNEL and PI staining showed that parthenolide selectively enhanced 4-HPR-induced apoptosis in Hep-3B and SK-Hep-1 cells. Subsequent observations using EMSA assay indicated that parthenolide effectively inhibited NF-κB activation during fenretinide-induced apoptosis. CONCLUSION:These findings indicate that parthenolide suppresses 4-HPR-induced apoptosis via inhibition of NF-κB activation and that NF-κB activation during fenretinide-induced apoptosis might have an anti-apoptotic effect.     

新疆阿勒泰地区罗布麻锈病发生动态及影响因子

由罗布麻栅锈菌(Melampsora apocyni)引致的锈病是影响罗布麻(Apocynum venetum)产业化的主要因素之一。本研究于2016年调查了新疆阿勒泰地区盐湖、红沟两个野生罗布麻和6龄、7龄栽培罗布麻锈病的发生动态,分析了野生和栽培罗布麻锈病发生与气象因子和生境等的相关性。结果表明,锈病均随罗布麻生长期的延伸而加重,其中盐湖、红沟罗布麻锈病分别在7月18日、8月3日达到发病高峰,发病率分别为86.47%和87.60%,随后发病率逐渐下降,生长末期下降至75.97%和53.78%;6龄、7龄栽培区锈病发病率分别在8月7日、7月23日达到发病高峰,发病率分别为25.52%和31.49%。野生罗布麻锈病病情指数和病害曲线下面积(AUDPC)分别为31.39~46.18和651.74~1 522.31,较栽培罗布麻相应指标高6.51~6.95倍及4.37~9.69倍。野生区罗布麻锈病的发生与降水量和植被总盖度显著正相关(P0.05),与物种多样性指数显著负相关(P0.05);栽培区罗布麻锈病的发生与罗布麻盖度显著正相关(P0.05),与物种多样性显著负相关(P0.05)。