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481.
We report a case resembling hydrolethalus syndrome in a Chinese family. Fetal polydactyly, syndactyly, encephalocele and cardiac malformation were detected on ultrasound examination at 12 weeks' gestation. Termination of pregnancy was performed, and postmortem examination confirmed the findings. This is the first report of a first-trimester prenatal diagnosis of hydrolethalus syndrome in the Chinese population. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
482.
483.
484.
Quantifying climate change mitigation potential in the United States Great Plains wetlands for three greenhouse gas emission scenarios 总被引:1,自引:0,他引:1
485.
Yechiel Soffer Avishay Goldberg Bruria Adini Robert Cohen Menachem Ben‐Ezra Yuval Palgi Nir Essar Yaron Bar‐Dayan 《Disasters》2011,35(1):36-44
Perceptions, knowledge and mitigation are factors that might play a role in preventing injury and loss of life during a major earthquake.2 Little is known about the relationships between different demographic and educational parameters and these factors. A national representative sample of 495 adults was investigated in order to determine the relationship between demographic and educational parameters in terms of the perceived threat, perceived coping, knowledge and mitigation of earthquakes in Israel. Compared to females, males perceived the threat of earthquakes to be lower (t=3.183, p=0.002), manifested higher levels of perceived coping (t=2.55, p=0.011), and had higher levels of earthquake related knowledge (t=2.047, p=0.041). We conclude that there are gender differences in perceptions and knowledge regarding earthquakes. 相似文献
486.
Maintaining the situational awareness of control room operators on offshore installations contributes to the timely diagnosis of conditions and making appropriate decisions. This is particularly important when dealing with events and incidents. Recent initiatives aimed at reducing operators’ exposure to the hazards of working on offshore installations may have a negative impact upon situational awareness within the control room environment.This paper discusses mitigation of the negative impact through the design and operation of the installation and control system; either by improving the general level of situational awareness or by specifically targeting the areas affected by these initiatives. 相似文献
487.
Spinal deformities are seen in fishes. Deformities in the family Syngnathidae is rarely reported. Spine curvatures in natural population of pipefish, Syngnathus abaster are reported from the Tunis North Lake. The species is euryhaline and occurs along the Mediterranean coasts. Four hundred specimens of S. abaster were collected from January 2006 to December 2007 from the Tunis North Lake. Two specimens with skeletal abnormalities were described for the first time. X-rays radiographies revealed several vertebral deformities for each deformed specimen, especially at five curvation places of the caudal part. Several factors are believed to be the cause of spinal deformities of S. abaster in the Tunis North Lake, such as environmental disturbances, parasitism infection and nutritional factors. 相似文献
488.
城市居住小区交通噪声的空间分布特征 总被引:4,自引:0,他引:4
根据实测所得交通流量和车型分布,采用预测为主、实测为辅的方法对典型居住小区进行了交通噪声预测与评价。对小区交通噪声的空间分布作了详细的分析,发现临街住宅交通噪声超标严重。另外,敏感点在建筑物中的朝向和楼层对交通噪声影响较大。上述空间分布规律对小区交通噪声评价与防治具有指导意义。 相似文献
489.
Social monogamy and extra-pair fertilization in an Australian lizard, Tiliqua rugosa 总被引:3,自引:0,他引:3
C. Michael Bull Steven J. B. Cooper Ben C. Baghurst 《Behavioral ecology and sociobiology》1998,44(1):63-72
This study investigates social monogamy in the Australian sleepy lizard, Tiliqua rugosa. At a 70-ha site near Mount Mary, South Australia, we radio tracked 55 adult female and 39 adult male lizards during their
spring activity periods. Each lizard was observed in 1–5 years. Females were observed with a single male partner on an average
of 10.8 days per year, although in 17.3% of cases, females were observed on 2 or fewer days with a male. The most intense
pairing period each year was 15 September–15 November when females were with male partners on an average of 36% of observation
days. Partnerships lasted an average of 43.3 days each year. After mating in early November, the pairs separated. Observations
of females pairing with other males were rare. Most males (82%) were also consistently monogamous, although 7 were observed
pairing with 2 females within one season. To investigate paternity, we allowed 21 gravid females to give birth to 42 offspring
in the laboratory. We determined genotypes at five polymorphic microsatellite DNA loci for the females, their male partners
and their offspring. Four litters (19%) and 6 of the offspring from those litters (14.3%) showed evidence of extra-pair fertilization
(EPF). Although the sample sizes are small, females of polygynous males were more likely to experience EPF.
Received: 22 February 1998 / Accepted after revision: 23 May 1998 相似文献
490.
Wet deposition of nitrogen and sulfur in Guangzhou, a subtropical area in South China 总被引:1,自引:0,他引:1
De-Yin Huang Yi-Gang Xu Ben Zhou Hui-Huang Zhang Jiang-Bo Lan 《Environmental monitoring and assessment》2010,168(1-4):429-439
Understanding the exchange mechanism between stratosphere and troposphere is one of the most important concerns of meteorologists and climatologists for decades. Different methods are being adopted to study those mechanisms. One of those methods is the study upon the tropospheric concentration of conserve or passive entities with stratospheric origin. One of those passive entities is 7Be that is produced upon the incident of cosmic rays on light atmospheric nuclei in the stratosphere. The availability of 5 years observations of 7Be concentration in surface air in Tehran (35°41′ N, 51°18′ E) encouraged us to investigate meteorological condition effect on the surface concentration of 7Be. Also, the intention was to see if there was any intrusion of stratospheric air into the troposphere at the time of high surface concentration of 7Be and scavenging mechanism when the concentration was low. During the course of this study, it has been found that 7Be concentration is high whenever there is a jet stream over Tehran. Since high-level jet streams normally form near tropopause folding, it could be interpreted as a sign of the intrusion of stratospheric air into the troposphere. It was also found that high concentration of 7Be in the Tehran surface air in summer is associated with an upper ridge on 500 hPa surface located east of the city, and low concentration in winter is associated with an upper trough. The latter normally is seen whenever there is precipitation that suggests wet scavenging could be the reason for that observed low concentration. 相似文献