Effects of arsenic on seed germination and physiological activities in wheat seedlings

The effects of arsenic(As)were investigated on seed germination,root and shoot length and their biomass and some other factors to elucidate the toxicity of As.The results showed low concentrations of As(O-1 mg/kg)stimulated seed germination and the growth of root and shoot,however,these factors all decreased gradually at high concentrations of As(5-20 mg/kg).The contents Of O2-,MDA,soluble protein and peroxidase(POD)activity all increased with increasing As concentrations.Soluble sugar content,ascorbate peroxidase(APX),and superoxide dismutase(SOD)activities decreased at low concentrations of As,and increased at high concentrations of As.While acetylsalicylic acid(ASA)and chlorophyll contents,catalase(CAT)activity displayed increasing trend when the concentrations of As was lower than 1 mg/kg,and then decreasing trend.By polyacrylamide gel electrophoresis(PAGE).As induced the expression of POD isozymes of wheat seedlings.As induced the expression of CAT isozymes but inhibited the expression of SOD isozymes of wheat seedlings at concentrations lower than 1 mg/kg.However,As inhibited the expression of CAT isozymes but induced the expression of SOD isozymes at concentrations higher than 5 mg/kg.The results indicated As could exert harmfulness in the early development stage of wheat at inappropriate concentrations.     

三峡库区水环境风险评估与预警平台总体设计与应用

为保障三峡库区水环境安全,提高环保部门的环境预警和应急科学处置能力,根据“平战结合”的平台建设思路,提出了基于面向服务(SOA)可扩展的架构、Webservice数据服务调用模式和模块化功能的平台构建技术,集成了地方环保业务系统的成果,设计和实施了一个体系、一张网、一张图、一张表、一个流程的“五个一”平台工程,研发了集污染源风险识别、环境预警监控、模拟预测、应急评估处置和信息发布5项功能为一体的三峡水环境风险评估与预警平台,并在重庆市环保部门实现了业务化运行应用. 平台研究成果可支撑应急管理和日常管理,并在一系列突发性事件中得到业务应用验证和应用,环境应急响应时间从1~2 h缩短至10~20 min,应急处置时间从原来的1~2 d缩短至1~2 h,显著提高了三峡库区水环境风险评估、预警和防范能力.      

预报预警在地质灾害防治中的应用

本文介绍了江西地质灾害气象预报模型的建立、计算方法,以及预警预报在地质灾害防治工作中获得的成功,对类似条件地区的地质灾害防治工作,具有一定的借鉴作用.     

An evaluation of a shared experience group for women and their support persons following prenatal diagnosis and termination for a fetal abnormality

Objectives Support after fetal diagnosis of abnormality (SAFDA), is a facilitated shared experience group for women and their partners or support person, in Victoria, Australia, who have had a pregnancy termination for a fetal abnormality. The objective of this study was to evaluate the SAFDA-facilitated group. Methods A questionnaire-based study was undertaken between 2001 and 2005 to evaluate SAFDA. A deidentified self-completed questionnaire was given to participants at the end of each group and included questions relating to the referring professional, participants' prior expectations of the group, helpfulness of participation, preferred group format, length, and venue. In addition, there was also opportunity for participants to make general comments on their experiences of participating in SAFDA. Results A total of 85 participants (100% response) completed the questionnaire. Seventy-one participants (84%) considered it ‘very helpful’ to participate in the group. Seventy-eight participants (92%) considered that a shared-experience group was the most beneficial format. Comments written by participants affirmed that the present format of SAFDA was a highly valued opportunity to listen to and share experiences in a confidential small group. Conclusion SAFDA is a beneficial forum for women and their partners or support person to share their experiences after having had a pregnancy termination for a fetal abnormality. Further, SAFDA provides information and insights for health professionals who are considering how best to support women. Copyright © 2007 John Wiley & Sons, Ltd.     

银纳米颗粒对黄菖蒲早期生长和生理特征的影响

N-AgNPs（银纳米颗粒）暴露对湿地植物的生长发育有重要影响,而N-AgNPs对大型湿地植物黄菖蒲（Iris pseudacorus）的影响尚不清楚.选取湿地植物黄菖蒲为受试物种,采用室内土培法分析柠檬酸钠包覆的N-AgNPs对黄菖蒲早期生长和生理特征的影响.结果表明:①不同ρ（N-AgNPs）〔分别为0、5、10、15、20 mg/L,依次记为N0（对照）、N5、N10、N15、N20〕处理和作用时间均会影响黄菖蒲生长和生物量积累.培养初期（0~14 d）,N5、N10处理会抑制黄菖蒲生长,而N15、N20处理会促进黄菖蒲生长;培养后期（14~35 d）,不同ρ（N-AgNPs）处理均抑制黄菖蒲生长.整个培养期内（0~35 d）,N5、N10处理均抑制黄菖蒲地上、地下生物量积累,而N20处理会促进黄菖蒲地上、地下生物量积累.②不同ρ（N-AgNPs）处理均降低了黄菖蒲叶绿素含量,提高了PSⅡ（光系统Ⅱ）反应中心的光能转换效率,降低了光氧化损伤的发生率;N5、N10、N15处理下黄菖蒲叶片PSⅡ功能反应中心的开放度降低、光合电子传递速率（ETR）变慢;N5和N20处理下黄菖蒲叶片光合电子传递活性（qP）增大,而N10和N15处理下光合电子传递活性降低.③各ρ（N-AgNPs）处理均显著降低了黄菖蒲叶片中的丙二醛含量,膜脂过氧化作用减弱;同时,增加了黄菖蒲叶片中w（脯氨酸）,对黄菖蒲产生较强的胁迫.研究显示,随着培养浓度的增加,ρ（N-AgNPs）对黄菖蒲生物量累积的影响由抑制作用变为促进作用;各ρ（N-AgNPs）处理均会降低黄菖蒲的叶绿素含量、增加w（脯氨酸）,对黄菖蒲的生长产生胁迫.      

基于可拓云模型的区域生态安全预警模型及应用——以祁连山冰川与水源涵养生态功能区张掖段为例

针对区域生态安全预警中的不确定性问题,考虑生态安全等级边界信息的随机性、模糊性及动态性,利用可拓学中兼具定性和定量分析及动态性的物元理论和具有不确定推理特性的云模型,提出了基于可拓云模型的区域生态安全预警模型;运用该模型对祁连山冰川与水源涵养生态功能区张掖段2005—2015年生态安全进行了定量评估,并对2017年生态安全环境进行动态预警。结果表明:祁连山生态功能区张掖段2005—2015年的生态安全整体水平均处于"理想"以下,其变化趋势为"较差"到"一般"再到"良好";2017年祁连山冰川与水源涵养生态功能区张掖段生态安全为"蓝色"预警,但有向"黄色"转变的趋势,其中工业三废、环保投入强度、森林覆盖率及人均水资源量是影响祁连山冰川与水源涵养生态功能区张掖段生态安全的主要因素。     

饮用水水源地水质监测预警管理信息系统开发与应用

结合饮用水水源地管理需求,设计开发包含在线监测、模拟分析、水质预警和风险应急等模块的饮用水水源地水质监测预警管理信息系统.本文介绍了该系统的功能设计.     

Prenatal diagnosis of anatomical connections in conjoined twins by use of contrast magnetic resonance imaging

Omphalopagus conjoined twins were diagnosed by ultrasonography in a pregnant woman at 21 weeks' gestation. In order to clarify the anatomical connections, magnetic resonance imaging (MRI) was performed, having achieved fetal paralysis by intravascular injection of 100 mg of pancuronium into each twin. Prior to MRI, 2 ml of a 0.0001 mmol/ml solution of gadolinium DTPA was also injected into the stomach of one twin. The contrast agent opacified the bowel loops of both twins, indicating bowel to bowel anastomosis. Following pregnancy termination, autopsy confirmed the prenatal diagnosis.     

银纳米颗粒对水葱早期生长和生理特征的影响

选取挺水植物水葱(Scirpus tabernaemontani)为受试物种,研究柠檬酸钠-银纳米颗粒(N-AgNPs)对水葱早期生长和生理特性的影响.结果表明:N-AgNPs显著促进了水葱叶片的生长,与N-0 mg·L~(-1)(对照组)相比,N-5 mg·L~(-1)、N~(-1)0 mg·L~(-1)、N~(-1)5 mg·L~(-1)、N-20 mg·L~(-1)处理组水葱叶片的生长速率分别增加20.7%、37.6%、42.9%、47.7%,生物量分别增加77.3%、158.2%、95.5%、127%,叶片中叶绿素含量分别增加23.3%、67.7%、85.2%、80.5%.N-AgNPs浓度与水葱的生长速率、生物量、叶绿素的含量呈正相关关系.另一方面,N-AgNPs浓度增大提高了光系统Ⅱ(PSⅡ)反应中心的光能转换效率(F_v/F_m),且N-AgNPs浓度与F_v/F_m呈显著正相关关系.N-5 mg·L~(-1)处理组水葱叶片PSⅡ功能反应中心开放度(ΔFv/Fm)最大,光合电子传递速率(ETR)最快,光合电子传递活性(qP)最大.然而,随着N-AgNPs浓度增大,水葱叶片PSⅡ功能反应中心开放度减小,光合电子传递速率逐渐变慢,光合电子传递活性逐渐降低.另外,N-AgNPs浓度增加降低了水葱叶片中的丙二醛含量,膜脂过氧化作用减弱;N-AgNPs浓度增加降低了水葱叶片中脯氨酸含量,水葱自我调节能力减弱.