Wax of a whitefly and its utilization by a chrysopid larva

Defense Mechanisms of Arthropods, no. 96; no. 95: Eisner et al.: Chemoecology (in press)     

贝类资源过度开发对印度东北海岸的影响

引言 生物多样性是生态系统结构和功能的一项基本属性.它是一连串概念[1],包括从基因学和分子生物学到群落结构和生境的异质性等多个相互联系的方面.生态学家利用多个指数量测生物多样性,所有这些指数或多或少直接地将种的数量与丰度和/或数量优势相联系[3].     

First trimester maternal serum placenta growth factor (PIGF)concentrations in pregnancies with fetal trisomy 21 or trisomy 18

Placenta growth factor (PIGF), an angiogenic factor belonging to the vascular endothelial growth factor family, pregnancy-associated plasma protein A (PAPP-A) and free β-human chorionic gonadotrophin (β-hCG) were measured in maternal serum from 45 pregnancies with trisomy 21, 45 with trisomy 18 and 493 normal controls at 10–13 completed weeks of gestation. In the normal pregnancies maternal serum PIGF levels increased exponentially with gestation. The median multiple of the median (MoM) PIGF concentration in the trisomy 21 group (1.26 MoM) was significantly higher (p<0.0001) than in the control group (1.00 MoM). In the trisomy 18 group the median PIGF was lower (0.889 MoM) but this did not quite reach significance (p=0.064). The corresponding median MoM values for PAPP-A were 1.00 MoM for the controls, 0.49 MoM for trisomy 21 and 0.16 MoM for trisomy 18. The median MoM values for free β-hCG were 1.00 MoM for the controls, 2.05 MoM for trisomy 21 and 0.38 MoM for trisomy 18. In the control group there was a small but significant correlation of PIGF with free β-hCG (r=+0.1024) and PAPP-A (r=+0.2288). In the trisomy 18 group there was a significant association between PIGF and free β-hCG (r=+0.2629) but not with PAPP-A (r=+0.0038). In the trisomy 21 group there was a small but significant association with PAPP-A (r=+0.1028) but not with free β-hCG (r=+0.0339). The separation of affected and unaffected pregnancies in maternal serum PIGF is small, and therefore it is unlikely that measurement of PIGF would improve screening for these abnormalities provided by the combination of fetal nuchal translucency and maternal serum PAPP-A and free β-hCG. Copyright © 2001 John Wiley & Sons, Ltd.     

某些剧毒有机废料在高温至超临界水中的处理实验

为了探索毒害有机废料的处理条件和反应机制,用二氨基乙二肟,氨基氰和蜜胺作初始试料,在温度１５０－４００℃,压力１００－７００×１０＾５Ｐａ的条件下进行了水热实验研究,部分密胺实验还添加了Ｈ２Ｏ２,实验结构表明,在水热条件下,尤其在超临界水中,二氨基乙二肟和氨基氰既可以通过热解作用而聚合成较高分子量的氮杂环混合物,进而水解转化成ＣＯ２和ＮＨ３,也可以直接发生水解作用,生成ＣＯ２和ＮＨ３,添加氧化剂可     

Congenital limb deficiencies in newborn infants: prevalence,characteristics and prenatal diagnosis

Congenital limb deficiency (CLD) occurs in 0.54 to 0.59/1000 live-born infants and varies according to its anatomic location, type and cause. Our aim was to present a fetus with a prenatal ultrasonographic diagnosis of CLD (transverse reduction deficiency of the left upper limb), and to determine the prevalence and clinical characteristics of CLD at a tertiary medical centre in Israel. Among 78 500 live-born infants, there were 24 cases of CLD (0.31/1000): 45.8% of the CLD cases with affected upper limbs, 45.8% with affected lower limbs, and 8.4% with both limbs affected; 88.4% of the limb deficiencies were longitudinal and 11.6% were transverse; and, 33.3% (8/24) of the affected newborn infants had additional congenital anomalies. We conclude that CLD is not an infrequent finding in live-born infants. Comprehensive ultrasonography of the fetus allows early prenatal diagnosis of CLD and provides the parents with important information and helps them in their decision regarding the fate of the pregnancy. Copyright © 2003 John Wiley & Sons, Ltd.     

Soil microbial response to herbicides applied to glyphosate-resistant canola

Adoption of glyphosate-resistant canola (Brassica napus L.) has increased glyphosate applications to this crop, and concerns have been raised about unintended consequences of these multiple applications. A field trial was conducted to evaluate the effects of pre-seed and in-crop glyphosate and alternative herbicides on soil microbial community functional structure, diversity and biomass. Pre-seed treatments were 2,4-D, glyphosate and 2,4-D + glyphosate, and in-crop treatments were glyphosate applied once, glyphosate applied twice, ethalfluralin, ethalfluralin + sethoxydim + ethametsulfuron + clopyralid, and sethoxydim + ethametsulfuron. Rhizosphere and bulk soil was collected at flowering stage of canola and analyzed for bacterial community-level substrate utilization patterns and microbial biomass C (MBC). Where differences were significant, pre-seed application of both 2,4-D and glyphosate altered the functional structure and reduced the functional diversity of soil bacteria, but increased MBC. These effects were not necessarily concurrent. The reduction in functional diversity was due to reduction in evenness, which means that the soil where both pre-seed herbicides had been applied was dominated by only few functional groups. In 1 year, two in-crop applications of glyphosate also reduced the functional diversity of soil bacteria when applied after pre-seed 2,4-D, as did in-crop sethoxydim + ethametsulfuron following pre-seed glyphosate. Even though significant differences between herbicides were fewer than non-significant differences, i.e., there were no changes in soil microbial community structure, diversity or biomass in response to glyphosate or alternative herbicides applied to glyphosate-resistant canola in most cases, the observed changes in soil microbial communities could affect soil food webs and biological processes.     

Ecodesign methods focused on remanufacturing

Understanding the product's ‘end-of-life’ is important to reduce the environmental impact of the products' final disposal. When the initial stages of product development consider end-of-life aspects, which can be established by ecodesign (a proactive approach of environmental management that aims to reduce the total environmental impact of products), it becomes easier to close the loop of materials. The ‘end-of-life’ ecodesign methods generally include more than one ‘end-of-life’ strategy. Since product complexity varies substantially, some components, systems or sub-systems are easier to be recycled, reused or remanufactured than others. Remanufacture is an effective way to maintain products in a closed-loop, reducing both environmental impacts and costs of the manufacturing processes. This paper presents some ecodesign methods focused on the integration of different ‘end-of-life’ strategies, with special attention to remanufacturing, given its increasing importance in the international scenario to reduce the life cycle impacts of products.