Partial trisomy 20p resulting from recombination of a maternal pericentric inversion: case report of a prenatal diagnosis by chorionic villus sampling

We report a case of prenatal diagnosis of trisomy 20p resulting from a maternal pericentric inversion. The diagnosis was confirmed on both chorionic villi and amniotic cells. This case underlines the fact that prenatal ultrasound diagnosis of this structural anomaly is difficult. The only early sonographic feature was increased nuchal translucency. Copyright © 2006 John Wiley & Sons, Ltd.     

Heritable pheromone blend variation in a local population of the butterbur borer moth Ostrinia zaguliaevi (Lepidoptera: Crambidae)

Summary. In a local population of Ostrinia zaguliaevi Mutuura & Munroe (Lepidoptera: Crambidae), extensive variation was found in the blend ratio of three sex pheromone components, (Z)-9-tetradecenyl acetate (Z9-14:OAc, 10.2-63.8%), (Z)-11-tetradecenyl acetate (Z11-14:OAc, 32.2-86.8%), and (E)-11-tetradecenyl acetate (E11-14:OAc, 2.1-11.9%). The variation was observed over a three-year period (2002-2004). Mother-daughter regression analyses have shown that although the heritability of the minor component E11-14:OAc was not significant, the heritability of the proportions of Z9-14:OAc and Z11-14:OAc were substantial (0.5–0.6). In artificial selection experiments, the mean % Z9-14:OAc in the sex pheromone changed significantly within three generations (37% in the control line, 48 and 52% for two lines selected for increase, and 23 and 30% for two lines selected for decrease). Despite these changes, the amounts of fatty acyl pheromone precursors, (Z)-9-, (Z)-11- and (E)-11-tetradecenoate, in the pheromone gland were not significantly affected by the selection. Taken together, variation in the pheromone blend of O. zaguliaevi is likely to be attributable to a few genes involved in the reduction or acetylation of fatty acyl pheromone precursors, the last two steps in pheromone biosynthesis.     

Dissolved Ions of Trace and Major Elements and in Suspended Sediments in the Nile, Egypt

Dissolved ions and suspended participates from twelve water samples from Sohag (different localities) and Aswan (behind and below the High Dam) areas were collected along the River Nile, upper Egypt, which is at present affected seriously by pressure of population, intense industrial and agricultural activities, and atmospheric fallout. Eighteen trace and nine major ions in solution and fourteen metals in suspension were analyzed to establish whether elements are of anthropogenic or natural origin. Results of this study show that the Nile water was contaminated with high concentrations of dissolved lead, and with copper, nickel and mercury to a lesser extent, suggesting that these contaminants are generated from anthropogenic activities. the other dissolved ions in the Nile are of natural origin because their metal concentrations fall within the range of the normal background and average world dissolved values for inland waters. Results show that the usual constituents of suspended particulates in the Nile seem to be some metals (Cu and Zn) adsorbed on iron and manganese oxide/hydroxide. the results also reveal that most trace and major metal particulates increase from south to north due to activities associated with the dense population living along the Nile banks. No significant differences were observed between the chemical composition of trace and major elements taken on the east and west river Nile banks.     

Germination,Growth, and Nodulation of Sesbania rostrata Grown in Pb/Zn Mine Tailings

Sesbania rostrata in pure and amended Pb/Zn tailings. About 90% of seeds of S. rostrata germinated in pure Pb/Zn tailings, which contained high concentrations of Pb, Zn, Cu, and Cd. Although seedling growth suffered from the adverse environment of Pb/Zn tailings, they became established on tailings stands, in the greenhouse, as well as on the actual tailings dam, and completed their life cycle in 4 months. Dry matter production and nitrogen accumulation was 3200 kg/ha and 69.4 kg/ha, respectively in the actual tailings dam. Applying inorganic fertilizer to Pb/Zn tailings led to no obvious improvement in growth and nodulation of S. rostrata, while tailings amended by river sediment or domestic refuse rich in organic matter improved the growth and nodulation of the species. Azorhizobium caulinodans survived and formed N-fixing stem and root nodules in S. rostrata grown in pure Pb/Zn tailings with a nodule biomass exceeding 300 mg fresh matter per plant.     

Maternal investment in Antarctic fur seals: evidence for equality in the sexes?

Studies of the otariids (fur seals and sea lions), a highly sexually dimorphic group, have provided conflicting evidence of differential maternal expenditure in male and female offspring and, thus, suggestions that they conform to predictions of investment theory are equivocal. Since the mid-1970s, a diversity of research on Antarctic fur seals (Arctocephalus gazella) including studies of their reproductive ecology, lactation energetics, and foraging behaviour have been conducted at Bird Island, South Georgia that have resulted in one of the more complete and diverse data sets for any species of otariid. These long-term data were reviewed to determine whether there was any evidence to support that differential maternal expenditure occurred in Antarctic fur seals. Most of the data examined were collected during five consecutive austral summers from 1988 through 1992 and included years in which local food resources were abundant and scarce. We were unable to detect differences in the sex ratios of pups at birth or sex-biased differences in growth rates estimated from serial data, the number of foraging trips made, the duration of attendance ashore, diving behaviour, suckling behaviour, or milk consumption in any year and in the duration of foraging trips or age at weaning in 2 of 3 years. In addition, we found no evidence of greater reproductive costs between mothers with sons or daughters relative to their reproductive performance the following year. In contrast, sex-biased differences were only found in the duration of foraging trips in 1990, the age at weaning in 1988, and consistently in growth rates estimated from cross-sectional data. We suggest that differential maternal expenditure does not occur in Antarctic fur seals because male pups probably do not gain greater benefit from additional maternal expenditure than female pups. After weaning, males experience a period of rapid juvenile growth over 3–4 years during which time body mass nearly trebles. This growth will almost certainly be dependent upon available food resources then rather than on any maternal expenditure received over the first 4 months of life and, thus, the assumptions of the Trivers and Willard hypothesis are probably invalid for Antarctic fur seals. Received: 10 July 1996 / Accepted after revision: 3 March 1997     

森林对污染物(SO42-)的过滤器效应研究

森林的过滤器效应是指森林对污染物所具有的净化缓冲作用,这是森林生态系统所具有的重要生态服务功能之一.森林生态系统对污染物的截留、吸附与净化一般是通过污染物在森林生态系统中的乔木层与灌草层植物、枯落物和土壤(微生物)等组分间的转化过程来实现,阐明森林生态系统各组分对污染物的净化效应是正确评估森林过滤器效应的关键.系统综述了森林生态系统各组分对污染物净化效应的国内外主要研究成果,指明了目前该方面研究存在的问题和努力的方向,并指出目前国内已有的大多数研究还处于实验观测与现象揭示阶段,缺乏对过程与机理的深入研究,很少进行多因素的动态综合研究和系统分析,这都限制了我们对森林生态系统对污染物净化过程内在运行机制和客观规律的正确认识和评估.把整个森林生态系统当作一个过滤器,从植物、凋落物、土壤、微生物几个亚系统方面介绍了森林过滤器对污染物净化缓冲作用方面的主要研究进展.     

Female sex pheromone of Ostrinia orientalis – throwing a light on the relationship between O. orientalis and the European corn borer, O. nubilalis

Summary. The sex pheromone of Ostrinia orientalis (Lepidoptera: Crambidae) was analyzed by gas chromatography–electroantennographic detection (GC–EAD), GC–mass spectrometry and a series of bioassays. Three EAD-active compounds were detected in the female sex pheromone gland extract, and identified as tetradecyl acetate (14:OAc), (Z)-11-tetradecenyl acetate (Z11-14:OAc) and (E)-11-tetradecenyl acetate (E11-14:OAc). The titers (ratio) of 14:OAc, Z11-14:OAc and E11-14:OAc in 3-day-old virgin females were 0.49 ng (10), 4.86 ng (98) and 0.10 ng (2), respectively. In a wind-tunnel bioassay, the 98:2 blend of Z11- and E11-14:OAc, but not Z11-14:OAc alone, elicited the same male behavioral responses as virgin females and crude gland extracts. 14:OAc was inactive by itself, and did not show any synergistic effect on the binary blend. Field trapping experiments also confirmed the attractiveness of the binary blend to O. orientalis males. Based on these results, we concluded that the sex pheromone of O. orientalis is a 98:2 mixture of Z11-14:OAc and E11-14:OAc. This sex pheromone is very similar to that of the Z-type European corn borer, O. nubilalis. The present finding raises the question of whether O. orientalis , which is indistinguishable from O. nubilalis based on external morphology, is a biologically distinct species independent from O. nubilalis.