Seroprevalence of camel brucellosis (Camelus dromedarius) in Somaliland

The present study was delineated to investigate the prevalence and risk factors of camel brucellosis in Northern Somalia (Somaliland). The study was carried out at three main districts of camel-rearing regions of Somaliland (Awdal, Waqoyi Galbed and Togdheer) in the period from July to November, 2008. A total of 1246 camel blood sera were randomly collected from 42 sporadic small scale camel herds. Two serological tests were used to screen all serum samples, Rose Bengal Plate Test (RBPT) and indirect ELISA (I-ELISA). Multivariate logistic regression was constructed to study the risk factors associated with Brucella seropositive cases. The overall prevalence of camel brucellosis in districts under investigation was 3.9% by RBPT and 3.1% by (I-ELISA). Multivariate logistic regression on animal level showed that locality (P < 0.05; OR: 6.254; CI, 1.186–32.976), herd size (P < 0.001; OR: 5.493; CI, 2.956-10–207), rearing with other ruminants (P < 0.001; OR: 12.433; CI, 3.957–39.060), and contact with other camels (P < 0.05; OR: 5.311; CI, 1.093–25.800) were the potential risk factors. However, herd size (P < 0.05; OR: 5.425; CI, 1.181–24.932), and rearing with other ruminants (P < 0.05; OR: 20.466; CI, 1.456–28.638) were recorded as risk factors on the herd level. The results of the present investigation indicate that the Brucella spp. exists within the camel herds in Somaliland. Further studies need to be done on Brucella infection in the other ruminants to determine which measure should be followed for control of brucellosis.     

海洋菌W11产中温淀粉酶的酶学特性

本研究从威海文登海域筛选获得一株产淀粉酶海洋菌W11,初步鉴定为弧菌,并探讨pH、温度、无机离子对淀粉酶活性和稳定性的影响及该酶底物浓度效应和Km值。结果表明：在pH7.5左右酶活性最高,pH在4.0～7.5范围内体现较强的稳定性。最适酶解温度为55℃,酶液在60℃以下有较好的热稳定性;Ba2＋、Mn2＋对淀粉酶有激活作用,而Cu2＋、Mg2＋、Zn2＋则抑制淀粉酶活性,表观Km值为0.973mg/mL。海洋菌W11所产的中温淀粉酶保存温度范围较广、适应pH作用的范围广及稳定性较强,将有着广泛的应用潜力。     

Folic Acid Content of Ready‐to‐Eat Cereals Determined by Liquid Chromatography‐Mass Spectrometry: Comparison to Product Label and to Values Determined by Microbiological Assay

Twelve popular ready‐to‐eat breakfast cereals fortified with folic acid were sampled in the United States in 2006, and the data have been incorporated into the USDA National Nutrient Database for Standard Reference. Cereals were collected from three statistically selected retail outlets in each of four primary census regions, and four composites of each product were prepared using random groupings of three locations each. Folic acid was determined using a validated LC‐MS method, with ¹³C‐folic acid as an internal standard, after trienzyme treatment and solid phase extraction. A cereal reference material (AACC VMA399) was analyzed as a control. Selected samples were also assayed using the standard microbiological method, with and without trienzyme extraction, to generate an estimate of endogenous folate. On average, as shown on the label, folate content was underestimated. In seven cereals, folate was within 5% of the declared value; in four cereals, it was 5–20% higher; and in two cereals, it was >20% greater, representing –75 to +69 μg/serving (mean 17) of the label value, equivalent to –19% to +17% of the 400 μg/daily value. The microbiologically determined folic acid was higher than LC‐MS by 10–67% (mean 40%). Therefore, use of label values might underestimate folate intake from some breakfast cereals.     

光敏核不育水稻花粉发育的细胞学研究与PCD检测

应用石蜡切片技术和脱氧核糖核苷酸转移酶介导的缺口末端标记法(TUNEL),对光敏核不育水稻农垦58S和可育水稻农垦58N的花粉及花药壁发育过程进行了研究。结果表明:农垦58S雄性败育起始于花粉母细胞形成期,在发育过程中持续进行,终结于单核晚期,形成典败型花粉;TUNEL检测显示,农垦58S的绒毡层细胞在花粉母细胞时期启动细胞程序性死亡(PCD),但解体过程缓慢,一直持续到花粉发育后期,使单核花粉无法获得所需的营养物质而败育。     

牡丹果荚基多孔碳材料对水中四环素的吸附

为解决牡丹果荚废弃物焚烧处理造成的环境污染及资源浪费问题,并进一步实现废弃物资源化利用,本文以生物质废弃物牡丹果荚为碳源,KHCO₃为活化剂,且牡丹果荚与活化剂质量比为1∶3,经一步活化法800 ℃煅烧2 h制备出孔结构发达的牡丹果荚基多孔碳（PC-800-3）材料吸附水中四环素。通过调控活化温度、牡丹果荚/KHCO₃质量比,得到的最佳产物 PC-800-3较直接热解的牡丹果荚基多孔碳（PC）比表面积增加60倍,298 K下对100 mg·L^-1四环素溶液的最大吸附量为394.3 mg·g^-1。通过比表面积孔径分析、扫描电子显微镜、傅里叶变换红外光谱、X射线衍射等对PC与PC-800-3进行表征,结果显示活化剂的加入促进了多孔碳中微孔与介孔的生成。选择PC-800-3进行后续吸附实验,吸附等温线和吸附动力学拟合结果表明吸附过程符合Langmuir等温模型和拟二级动力学模型,热力学实验证实吸附为自发吸热过程,以单分子层物理吸附为主,存在静电相互作用。所制备的PC-800-3材料在较宽pH范围内和离子干扰下的吸附性能良好。再生实验表明,PC-800-3具有良好的重复利用性能。因此,将牡丹果荚转化为多孔碳制备性能优异的吸附剂,在解决水环境中抗生素污染问题的同时拓宽了其应用范围,进一步实现了废弃生物质的资源化利用。     

茶皂素在刺参苗期对玻璃海鞘杀除效果的研究

为寻求刺参苗种生产期间清除玻璃海鞘的有效方法,以天然环保的茶皂素作为杀虫药物,研究了不同质量浓度的茶皂素溶液对玻璃海鞘的杀除效果及对参苗的影响.试验结果显示,茶皂素对玻璃海鞘具有致死作用,用质量浓度为5、10、20 mg/L的茶皂素溶液浸浴处理12 h,玻璃海鞘的杀除率分别为32.3％、67.7％、83.3％,用质量浓...     

Supplementation of Selenium Nanoparticles-Loaded Chitosan Improves Production Performance,Intestinal Morphology,and Gut Microflora in Broiler Chickens

The current study aimed to evaluate the efficacy of selenium nanoparticles (SeNPs), combined or loaded with chitosan (COS), in broiler chickens reared under standard management protocols. The parameters under investigation were production performance, organ development, components of the intestinal barrier, and ileal microbial count. Two hundred and forty day-old chicks were raised in five groups, with each group containing eight replicates (n=6/replicate). The control group received a basal diet whereas the other four groups received basal diets supplemented with SeNPs (0.5 mg/kg), COS (200 mg/kg), SeNPs+COS (0.5 mg/kg SeNPs + 200 mg/kg COS), and SeNPs-loaded COS (SeNPs-L-COS) (200 mg/kg) respectively. On day 35, two birds/replicate were sampled to collect the viscera under investigation. The results revealed that dietary inclusion of SeNPs-L-COS increased (p<0.05) the body weight gain and improved (p<0.05) feed conversion ratio. Similarly, SeNPs-L-COS supplementation increased (p<0.05) the small intestinal villus surface area as well as the count of acidic goblet cells and intraepithelial lymphocytes when compared with the control group. Whereas the total goblet cell count was higher (p<0.05) in the small intestines of both the SeNPs+COS and SeNPs-L-COS groups. Microbial analysis of ileal contents also revealed an increase (p<0.05) in Lactobacilli species count with a concurrent decrease (p<0.05) in Escherichia coli count in the SeNPs-L-COS group when compared with the COS and control groups. Based on the results of the current trial, we can conclude that supplementation with SeNPs-L-COS is a superior combination for promoting the gut health and performance of broilers.     

实现绿化减排的途径探讨

笔者分析了影响人类生存环境的因素,提出节能减排是环境友好型社会建设的必然要求,并进行了实现绿化减排的途径探讨,以供同仁参考。     

基于模糊控制理论的温室茶树灌溉控制策略研究

水肥一体化技术在很大程度上弥补了原先灌溉手段的缺陷，其主要将施肥同灌溉相融合，其中提升灌溉的准确度具有十分重要的作用。结合模糊控制理论，针对茶树水肥一体化灌溉中的精确灌溉这一问题，设计温室茶树灌溉模糊控制系统，使用2019年9月1-20日有关于茶树的相关信息开展验证工作，通过结果我们能够发现该系统具备较为理想的调节作用。Matlab仿真结果研究表明，温室茶树模糊控制器能有效提高茶树对水的利用效率，为实现精确灌溉提供了可行性。     

中国银行业的专利信息及专利发展

检索中国银行业1985~2012年三类专利（发明专利、实用新型专利和外观设计专利）的申请总量、申请年度趋势、主要银行申请数量、专利发明人数、专利涉及的主要IPC分类号等信息，考量中国银行业的专利发展整体状况，特别是最具技术创新代表性的发明专利，结果显示：外资银行比内资银行更注重发明专利，外资银行发明专利的发展比内资银行起步要早，但发展较平缓；内资银行发明专利发展较快，申请数量高于外资银行。鉴此，中国银行业需加大对发明专利的研发投入，培养科技创新人才，提升专利发明质量。