Phosphorus status and microbial community of paddy soil with the growth of annual ryegrass (Lolium multiflorum Lam.) under different phosphorus fertilizer treatments

Annual ryegrass (Lolium multiflorum Lam.) was grown in paddy soil in pots under different phosphorus (P) fertilizer treatments to investigate changes of P fractions and microbial community of the soil. The treatments included Kunyang phosphate rock (KPR) applications at 50 mg P/kg (KPR50) and 250 mg P/kg (KPR250), mono-calcium phosphate (MCP) application at 50 mg P/kg (MCP50), and the control without P application. The results showed that KPR50, KPR250, and MCP50 applications significantly increased the dry weight of the ryegrass by 13%, 38%, and 55%, and increased P uptake by 19%, 135%, and 324%, respectively. Compared with MCP50, the relative effectiveness of KPR50 and KPR250 treatments in ryegrass production was about 23% and 68%, respectively. After one season ofryegrass growth, the KPR50, KPR250, and MCP50 applications increased soil-available P by 13.4%, 26.8%, and 55.2%, respectively. More than 80% of the applied KPR-P remained as HCI-P fraction in the soil. Phospholipid fatty acid (PLFA) analysis showed that the total and bacterial PLFAs were significantly higher in the soils with KPR250 and MCP50 treatments compared with KPR50 and control. The latter had no significant difference in the total or bacterial PLFAs. The KPR50, KPR250, and MCP50 treatments increased fungal PLFA by 69%, 103%, and 69%, respectively. Both the principal component analysis and the cluster analysis of the PLFA data suggest that P treatments altered the microbial community composition of the soils, and that P availability might be an important contributor to the changes in the microbial community structure during the ryegrass growth in the paddy soils.     

烤鸭肉在储存过程中菌群结构变化研究

探究烤鸭储存过程中菌群的变化,为延长其贮存期奠定理论基础．用酚、氯仿、异戊醇法提取烤鸭肉中细菌的基因组DNA,PCR扩增16SRNAV3区,用DGGE电泳技术分析菌群结构的变化情况,然后用Bionumerics软件对DGGE分子指纹图谱进行烤鸭肉菌群结构相似性分析．PCR结果表明,成功扩增了细菌基因组DNA,为230bp;DGGE实验结果表明,DGGE分子指纹图谱上条带存在显著差异;用bionumberics软件分析,发现样本相似度不断变化,表明在储存过程中,烤鸭肉菌群结构发生了变化．该研究为延长烤鸭肉保质期提供理论参考依据．     

吲哚美辛对小鼠肾缺血再灌注损伤的保护作用(英文)

研究目的:在小鼠模型中利用吲哚美辛阻断COX-1/2通路,探讨非甾体类抗炎药对肾缺血再灌注损伤的保护作用。创新要点:非甾体类抗炎药被认为具有肾毒性,本研究首次在小鼠模型中探讨非甾体类抗炎药对肾缺血再灌注损伤的保护作用。研究方法:小鼠左侧肾蒂夹闭后,通过腹腔注射不同剂量的吲哚美辛,在肾缺血再灌注损伤24小时后,获取血液和肾脏标本。利用酶联免疫(ELISA)试剂盒测定血清肌酐和细胞因子浓度来评估肾功能,肾组织样本进行苏木精-伊红染色和免疫组化分析。重要结论:腹腔注射吲哚美辛5 mg/kg组的小鼠血清肌酐值与对照组相比显著降低,肾小管损伤也显著减轻(见图1和2);腹腔注射5和7 mg/kg吲哚美辛组的小鼠血清肾肿瘤坏死因子-α和白介素-6的浓度显著降低(见图3a和3b);腹腔注射3和5 mg/kg吲哚美辛组的小鼠血清血栓素B2与6-酮前列腺素F1α的比值明显降低(见图3c);腹腔注射5 mg/kg吲哚美辛组小鼠肾组织COX-1和COX-2染色较弱(见图4)。因此,吲哚美辛对小鼠肾缺血再灌注损伤的作用与其剂量相关,在某个特定的剂量范围内具有肾保护作用。吲哚美辛对小鼠肾缺血再灌注损伤的保护作用与阻断COX-1/2有关。     

Microbial activity and community diversity in a variable charge soil as affected by cadmium exposure levels and time

Effects of cadmium (Cd) on microbial biomass, activity and community diversity were assessed in a representative variable charge soil (Typic Aquult) using an incubation study. Cadmium was added as Cd(NO3)2> to reach a concentration range of 0～16 mg Cd/kg soil. Soil extractable Cd generally increased with Cd loading rate, but decreased with incubation time. Soil mi-crobial biomass was enhanced at low Cd levels (0.5～1 mg/kg), but was inhibited consistently with increasing Cd rate. The ratio of microbial biomass C/N varied with Cd treatment levels, decreasing at low Cd rate (<0.7 mg/kg available Cd), but increasing progressively with Cd loading. Soil respiration was restrained at low Cd loading (<1 mg/kg), and enhanced at higher Cd levels. Soil microbial metabolic quotient (MMQ) was generally greater at high Cd loading (1～16 mg/kg). However, the MMQ is also affected by other factors. Cd contamination reduces species diversity of soil microbial communities and their ability to metabolize different C substrates. Soils with higher levels of Cd contamination showed decreases in indicator phospholipids fatty acids (PLFAs) for Gram-negative bacteria and actinomycetes, while the indicator PLFAs for Gram-positive bacteria and fungi increased with increasing levels of Cd contamination.     

Diversity change of microbial communities responding to zinc and arsenic pollution in a river of northeastern China

Pollution discharge disturbs the natural functions of water systems. The environmental microbial community composition and diversity are sensitive key indicators to the impact of water pollutant on the microbial ecology system over time. It is meaningful to develop a way to identify the microbial diversity related to heavy metal effects in evaluating river pollution. Water and sediment samples were collected from eight sections along the Tiaozi River where wastewater and sewage were discharged from Siping City in northeastern China. The main pollutants contents and microbial communities were analyzed. As the primary metal pollutants, zinc (Zn) and arsenic (As) were recorded at the maximum concentrations of 420 and 5.72 μg/L in the water, and 1704 and 1.92 mg/kg in the sediment, respectively. These pollutants posed a threat to the microbial community diversity as only a few species of bacteria and eukaryotes with strong resistance were detected through denaturing gradient gel electrophoresis (DGGE). Acinetobacter johnsonii, Clostridium cellulovorans, and Trichococcus pasteurii were the dominant bacteria in the severely polluted areas. The massive reproduction of Limnodrilus hoffmeisteri almost depleted the dissolved oxygen (DO) and resulted in the decline of the aerobic bacteria. It was noted that the pollution reduced the microbial diversity but the L. hoffmeisteri mass increased as the dominant community, which led to the overconsuming of DO and anaerobic stinking water bodies. Water quality, concentrations of heavy metals, and the spatial distribution of microbial populations have obvious consistencies, which mean that the heavy metals in the river pose a serious stress on the microorganisms.     

Distribution of Bacterial Communities in Petroleum-Contaminated Soils from the Dagang Oilfield,China

Diversity in bacterial communities was investigated along a petroleum hydrocarbon content gradient (0–0.4043 g/g) in surface (5–10 cm) and subsurface (35–40 cm) petroleum-contaminated soil samples from the Dagang Oilfield, China. Using 16S rRNA Illumina high-throughput sequencing technology and several statistical methods, the bacterial diversity of the soil was studied. Subsequently, the environmental parameters were measured to analyze its relationship with the community variation. Nonmetric multidimensional scaling and analysis of similarities indicated a significant difference in the structure of the bacterial community between the nonpetroleum-contaminated surface and subsurface soils, but no differences were observed in different depths of petroleum-contaminated soil. Meanwhile, many significant correlations were obtained between diversity in soil bacterial community and physicochemical properties. Total petroleum hydrocarbon, total organic carbon, and total nitrogen were the three important factors that had the greatest impacts on the bacterial community distribution in the long-term petroleum-contaminated soils. Our research has provided references for the bacterial community distribution along a petroleum gradient in both surface and subsurface petroleum-contaminated soils of oilfield areas.     

Chelators effect on soil Cu extractability and uptake by Elsholtzia splendens

INTRODUCTIONPhytoremediation,thatuseofgreenplantstodecontaminateCuandotherheavymetalsinsoils,isanemergingtechniquewithadvantagesofbeinginsitu,cost-effectiveandenvironmentallysus-tainable(Chanyetal.,1997;Cunninghametal.,1997;Saltetal.,1998).Theavailabilityofmetalinthesoilforplantuptakeisoneimportantlimitationforsuccessfulphytoremediation(Blaylocketal.,1997).Forexample,lead(Pb)isoneofthemostimportantenvironmentalpollutants,haslimitedsolubilityinsoils,andisavailableforplantuptakeduetocompl…     

Changes in bacterial community of anthracene bioremediation in municipal solid waste composting soil

Polycyclic aromatic hydrocarbons (PAHs) are common contaminants in a municipal solid waste (MSW) composting site. Knowledge of changes in microbial structure is useful to identify particular PAH degraders. However, the microbial community in the MSW composting soil and its change associated with prolonged exposure to PAHs and subsequent biodegradation remain largely unknown. In this study, anthracene was selected as a model compound. The bacterial community structure was investigated using terminal restriction fragment length polymorphism (TRFLP) and 16S rRNA gene clone library analysis. The two bimolecular tools revealed a large shift of bacterial community structure after anthracene amendment and subsequent biodegradation. Genera Methylophilus, Mesorhizobium, and Terrimonas had potential links to anthracene biodegradation, suggesting a consortium playing an active role.     

甲氨蝶呤联合益赛普治疗类风湿风湿关节炎

目的评价甲氨蝶呤联合益赛普治疗类风湿关节炎（RA）临床疗效以及安全性.方法随机将90例类风湿关节炎患者分为2组：联合治疗组45例,口服甲氨蝶呤10～15 mg 1次/周,益赛普50 mg 1次/周,皮下注射;对照组45例单用甲氨蝶呤10～15mg 1次/周.疗程为3月,对2组的临床症状及实验室指标改善情况进行评价.结果2组的临床症状即关节疼痛数、关节肿胀数的改善均有良好效果,联合治疗组优于对照组;2组治疗后血沉（ESR）、C反应蛋白（CRP）均明显降低,且联合治疗组优于对照组.安全性方面,联合用药组一例出现肺部感染,停药及给予消炎药后好转.1例最初出现注射局部皮肤红肿伴瘙痒,3d后自行消失,未影响患者正常用药.对照组1例于服用甲氨蝶呤第2日出现头晕及胃肠道不适,1例出现口腔溃疡,1例化验血常规白细胞降低.结论甲氨蝶呤联合益赛普治疗类风湿关节炎疗效肯定,不良反应少,且明显较单用甲氨蝶呤组效果好.     

土壤环境对菌肥移居微生物各生理群生长的影响

以灭菌茶园土壤施入混合菌肥,探讨茶叶专用菌肥微生物在不同土壤环境中存活状况、变化规律.结果表明菌肥细菌生长适宜的土壤环境条件是土壤含水量为20-25％,土壤温度为25℃,pH4左右的酸性土壤石灰添加量为0.4-0.8％（约土壤pH6.6-7.3）为宜;制约菌肥放线菌在土壤中生长繁殖因素主要为土壤pH和含水量,以土壤pH6.6-7.3,含水量为15-20％为宜.土壤环境因素对菌肥真菌生长的影响大小排序依次为pH、水分和温度,酸性土壤最有利于真菌的生长繁殖.     

社区发展与社区精神文明建设论略

社区发展是在全球范围内广泛推行的一项社会工作方法,而社区精神文明建设则是社区发展高级阶段的基本要求和重要表现,是在社会主义市场经济条件下广泛发动群众积极参与社区发展实践的一种新形式,是把精神文明建设和城乡社会管理的各项工作真正落实到基层的一项重要措施。其内容包括宏观上的社区文化建设、社区教育建设、社区服务建设,中观上的社区道德建设,微观上的文明家庭建设和文明村组建设等方面。为此,必须把社区发展和社区精神文明建设有机结合起来,从多方面来加强社区精神文明建设。     

Study of cellulolytic soil fungi and two nova species and new medium

This study is aimed at identifying and determining the percentage of occurrence frequency of cellulose decomposing soil fungi. The soil samples were inoculated into culture plates prepared in Sabouraud medium under sterilized conditions and incubated at 30 ℃ for 4 to 7 d. The identified fungal species were incubated in self-designed cellulose medium for testing their cellulolytic ability. Forty-two species, including2 nova species, representing sixteen genera showed growth and sporulation in the cellulose medium. Most of the isolated species were from genus Aspergillus and Penicillium. Aspergillus niger and Mucor hiemalis showed highest occurrence frequency （45% and 36% respectively）, as these species were collected from about 80% of soil samples. Being agar free and cheaper, the new fungal medium designed showed results equivalent to Sabouraud medium.     

美国纽约市的学习型社区建设透析

随着终身教育、学习社会、终身学习等教育理念在全球的风靡,如何实现由理论到实践的转换成为各国进一步关注的焦点。而社区作为不同地域人们生活的基本单位,学习型社区的实现成为国家范围内建成学习社会的必由之路。纽约作为国际化大都市的典型,在充分利用社区资源、组织多样化的教育活动、改善社区教育管理等方面均凸显出自身特色,因此可为我国城市社区建设提供良好的借鉴。     

教育微博社群中首帖质量的分析与对策

随着微博的兴起,微博社群在教育领域中的应用已成为研究热点之一,而首帖质量直接影响着学习者使用微群的学习效果。通过介绍影响因子理论的内涵和价值,概述了微群的定义和特点,将影响因子引入到微群首帖研究中,创建同类首帖影响因子概念,选取多个样本进行研究,对其内容进行编码分析,并采用调查问卷和访谈法对结果进行了验证,以此对微群首帖提出建议,促进其在教育领域中的有效应用。     

ICU感染病原菌的检出率及其耐药性分析

目的：回顾性的分析某医院重症监护室（ICU）2012年1月1日至2012年12月31日之间感染病原菌的分布及其耐药情况。方法：用VITET-2Compact60全自动微生物分析仪鉴定细菌,K—B纸片扩散法做体外药敏试验,统计、分析细菌的检出率和药敏结果。结果：799份ICU标本,医院感染分离菌株249株,检出率31．16％。首位是洋葱伯克霍尔德菌（60株,24．10％）,其次鲍曼不动杆菌（55株,22．09％）,第三是肺炎克雷伯菌（39株,15．66％）。分离菌中标本来源痰和咽拭子最常见,其次静脉血、静脉导管。洋葱假单胞、鲍曼不动杆菌、铜绿假单胞菌、肺炎克雷伯菌、大肠埃希菌、人葡萄球菌及金黄色葡萄球菌对多种抗菌药物均具有较高的耐药性。结论：医院感染病原菌中以非发酵菌的检出率最高,其次是肺炎克雷伯菌并且耐药性强。因此治疗医院感染病原菌所致的感染性疾病应根据体外药敏试验结果选用敏感的抗菌药物,减低耐药率。     

Investigation of iodine concentration in salt,water and soil along the coast of Zhejiang,China

Objective: We aim to describe the environment iodine concentration in salt, water and soil along Zhejiang Province coast in the China foreland. It will be helpful for us to judge whether this area is insufficient in iodine and universal iodized salt is necessary or not. Methods: We collected iodized salt samples, drinking water samples (tap water in the towns, and well water or spring water in the villages), water samples from different sources (ditches, lakes, rivers) and soil samples through random sampling in June, 2005. Salt, water and soil iodine was detected by arsenic-cerium redox method. Statistical analysis was expressed as mean±SEMby Windows SPSS 13.0. Results: (1) The iodine concentration in salt was 27.9±4.33 mg/kg (n=108). (2) Seventy-five water samples were collected. The water iodine value was 0.6～84.8 μg/L (mean of 11.66 μg/L). The watershed along the Qiantang River has significantly higher iodine content than the water in Lin'an in mountain area (P＜0.01). The iodine content and mean iodine content of tap water, well or spring water and natural water sources were 4.30±2.43 μg/L (n=34), 23.59±27.74 μg/L (n=19)and 12.72±10.72 μg/L (n=22) respectively. This indicated that among environmental water sources, the ditch iodine content was the highest with river water iodine being the lowest (P＜0.01). (3) Soil iodine value was 0.11～2.93 mg/kg (mean of 1.32 mg/kg).Though there was no statistical difference of soil iodine in different districts (P=0.131), soil iodine content correlated positively with water iodine content. Conclusion: Iodine concentration in salt accords with national policy of adding iodine in salt. Foreland has more iodine in water than mountain area. The data reflected that water and soil iodine in foreland area was not high, which suggests universal iodized salt should be necessary. Environment iodine has relatively close association with pollution.     

SCAR分子标记监测菌群中的哈茨木霉

研究目的：开发具有种属特异性序列特征性扩增区域（SCAR）标记物来监测哈茨木霉在其入侵的试验菌群中的定殖和生长,为哈茨木霉应用于生物防治等生态和生物技术中提供支撑。 创新要点：多种木霉属真菌能与各种微观和宏观的生物有机体建立相互作用。利用这些相互作用,木霉可做为原生种群的入侵物种而用于生物防治。本文通过使用试验菌群为研究模型,利用随机扩增多态性DNA（RAPD）技术和序列特征性扩增区域（SCAR）标记物来监测菌群中哈茨木霉的生长状态。 研究方法：利用随机扩增多态性DNA（RAPD）技术,从16个10聚体引物进行多态性筛选,其中1个引物扩增出对应哈茨木霉的条带。对该条带进行克隆测序,并设计5个20-23聚体引物。成功利用引物对2F2／2R2和2F2／2R3278分别特异性地扩增出哈茨木霉BpTloa菌株278bp和448bp的DNA片段。同时,用这两个引物对14个哈茨木霉菌株和几种不同的真菌菌株进行特异性对照试验,也只成功扩增出哈茨木霉菌株。此外,使用真菌DNA混合物和试验真菌群的DNA为模板,采用实时聚合酶链式反应（PCR）对引物对2F2／2R2进行评估。当仅使用100份SCAR标记物或哈茨木霉仅占整个菌群的0．1％时,仍能检测出哈茨木霉。 重要结论：本研究所建立的SCAR分子标记能有效监测菌群中的哈茨木霉的定殖和生长,具有较高特异性、灵敏度和准确度。     

Toxicity of cadmium to soil microbial biomass and its activity：Effect of incubation time on Cd ecological dose in a paddy soil

INTRODUCTION Cadmium (Cd) is ubiquitous in the human en-vironment and has been recognized as one of the mostdeleterious heavy metal pollutants (Robards andWorsfold, 1991; Christine, 1997). It may easily movefrom soil to food plants through root absorption andaccumulate in their tissues (Oliver, 1997). In this way,Cd may enter the food chain and affect human health(Adriano, 1986). Among many heavy metals pollut-ing soil, Cd is of concern because of its potentiallyharmful effects on…     

豫灵冶炼厂周边土壤重金属污染及植物重金属累积特征研究

了解豫灵土壤污染现状和筛选重金属富集植物对污染土壤进行修复,采用火焰原子吸收光度法对豫灵冶炼厂周边土壤中重金属含量进行了测定,并对7种植物铅、镉的吸收和富集能力进行了研究,结果表明：豫灵冶炼厂周边土壤中Pb、Cd的含量严重超标,分别为821.574mg/kg和62.207mg/kg。采集的7种植物样品对Pb、Cd的吸收能力存在明显差异,苦荬菜、茵陈蒿和播娘蒿对Pb、Cd的吸收能力均较强,植物体内Pb的含量分别为423.95、358.275和303.5mg/kg,Cd的含量分别为54.60、49.425、55.175mg/kg。茵陈蒿和播娘蒿属于杂草,适应性强,利用其对矿区土壤进行修复,不经人工干预即可正常生长,成本较低,因此可作为该污染区土壤修复的选择物种。     

政府与社区：共生、互补、双赢--以武汉市江汉区创新社区治安运作体系的实验为例

正确理解和处理政府与社区的关系问题，是社区建设中的难点问题，是关乎社区建设能否继续推进的关键性问题。本以武汉市江汉区理顺区公安分局与社区关系的实验为个案，分析了江汉区新的社区治安运作体系的起因、、过程、合理性和效应，指出政府与社区的关系是体系上的共生关系、功能上的互补关系、效用上的双赢关系。