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91.
Abstract

14C‐p,p'‐DDT‐bound residues in soil can be released by treatment with concentrated sulphuric acid at ambient temperatures. Within 6 days, about 70% of the bound residues was released. Bound residues released after 9 months incubation with 14C‐DDT showed the presence of DDT and DDE only while bound residues released after 18 months, contained in addition 13% DDD.

Release of bound 14C‐residues also occurs readily following inoculation of the soil‐bound residues with fresh soil or with individual microorganisms. Almost complete release of bound residues was observed after incubation for 45 days. The rate of release was rapid during the first two weeks and decreased thereafter. TLC and HPLC analysis showed that the released residues contained DDE (about 80%) and a smaller amount of DDD. The disappearance of DDT from the released residues may be attributed to its microbiological degradation to DDE and DDD, shortly after its release.  相似文献   
92.
“十四五”时期是我国全面建成小康社会、实现第一个百年奋斗目标之后,乘势而上开启全面建设社会主义现代化国家新征程、向第二个百年奋斗目标进军的第一个五年,我国将进入新发展阶段。通过研究新发展阶段需求,分析生态环境监测存在的问题和短板,指出在职能转变、“减污降碳”、“真、准、全”等方面距离深入治污攻坚要求存在的差距,并以新发展理念为指导,研究提出生态环境监测体系与监测能力现代化建设的内涵实质、重要基础以及关键突破口,为加快构建生态环境监测新发展格局提供参考。  相似文献   
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Are Alaska-style citizen revenue distribution funds the solution to the resource curse in developing countries as their proponents conjecture? Unfortunately it appears not. First, it is questionable whether developing countries have the institutional capacity to implement and operate such funds successfully. Second, citizen funds are unlikely to have any substantial impact on governance and their macroeconomic effects are uncertain. Finally, as a comparative case study of the three natural resource-intensive economies that successfully steered clear of excessive real appreciation and crowding out of the non-minerals tradables sector—Botswana, Indonesia and Norway—shows, citizen funds are likely to carry detrimental indirect effects on the ability of governments to surmount the Dutch Disease.  相似文献   
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This is a case report of the prenatal diagnosis of a de novo interstitial duplication of chromosome 2 (46,XX,dup(2)(p13p21) de novo) with an associated phenotypic abnormality. This chromosomal duplication is rare, only one has previously been described prenatally. Postnatal reports of similar duplications in this region have described associated dysmorphic features and significant neurodevelopmental delay. In our case, the only ultrasound finding was moderately severe ventriculomegaly. At post-mortem, ventriculomegaly was confirmed and there was associated macrocephaly (head circumference above the 97th centile) with no dysmorphic features seen. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
98.
This paper examines whether Russia suffers from “Dutch Disease” by investigating the real appreciation of the Russian ruble and the relative de-industrialization in the post Soviet Union-era. According to UNDP Russia Report (2009) the Russian economy has indeed exhibited some typical symptoms of “Dutch Disease” in recent years as upward movements in oil prices are accompanied by a reduction in the share of manufacturing output and an increase in service prices. Furthermore, the report claims that these developments may trigger a recession in Russia in the future. Using Gregory and Hansen (1996a, 1996b) and Arai and Kurozumi (2007) structural break cointegration frameworks, our results indicate that the Russian economy exhibits some typical symptoms of “Dutch Disease”. Although the diagnosis is not certain, the risk is evident. Hence, policies that would make the Russian economy more robust to shocks in the oil price need to be carefully designed and implemented.  相似文献   
99.
Occipital encephalocele belongs to the family of neural tube defects, which occur in one among 2000 to 5000 live births. Syndromic encephaloceles include Meckel–Gruber syndrome and various chromosomal abnormalities. We report on a fetal case (13 WG) with bilateral cleft lip and palate, choanal atresia, occipital encephalocele, bilateral club feet, bilateral multicystic kidneys, enlarged bladder and urethral atresia. The fetal chromosome analysis showed a maternally inherited unbalanced translocation between the short arm of chromosome 1 and the long arm of chromosome 14, resulting in 1p35-pter deletion and 14q32-qter duplication (46,XY,der(1),t(1;14)(p35;q32)). Since the chromosomal breakpoints have not previously been implicated in syndromic encephalocele, this observation is of interest for the identification of other genes responsible for occipital encephalocele. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
100.
Charcot-Marie-Tooth disease type 1A (CMT1A) is a frequent hereditary motor and sensory neuropathy of the peripheral nerves. In most cases, the disease is associated with a 1.5 Mb tandem duplication at 17p11.2. A 42-year-old pregnant woman requested prenatal diagnosis because of her age and since both her husband and two children were severely affected with CMT1. The CMT1A duplication was demonstrated in the father's, the two children's, and the fetus's DNA using different molecular genetic methods. Although cytogenetical analysis showed a normal female karyotype in the fetus, the parents decided to terminate the pregnancy because of the genetic risk associated with the CMT1A duplication.  相似文献   
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