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451.
根据2011年-2015年夏季青岛第一海水浴场主要水质指标(水温、pH、漂浮物、石油类、粪大肠菌群)的监测结果,按照游泳适宜度分级规定分析评价了各年度海水浴场的水质状况,详细分析了各监测指标,除粪大肠菌外其它各项指标均达到二类海水水质标准.监测结果表明:青岛第一海水浴场水质总体优良,游泳适宜度为最适宜游泳或适宜游泳,粪大肠菌群是首要污染物质,需要引起有关部门重视,并对粪大肠菌群的超标原因进行了分析,最后提出了相关的建议措施.  相似文献   
452.
Although career proactivity has positive consequences for an individual's career success, studies mostly examine objective measures of success within single countries. This raises important questions about whether proactivity is equally beneficial for different aspects of subjective career success, and the extent to which these benefits extend across cultures. Drawing on Social Information Processing theory, we examined the relationship between proactive career behaviors and two aspects of subjective career success—financial success and work‐life balance—and the moderating role of national culture. We tested our hypotheses using multilevel analyses on a large‐scale sample of 11,892 employees from 22 countries covering nine of GLOBE's 10 cultural clusters. Although we found that proactive career behaviors were positively related to subjective financial success, this relationship was not significant for work‐life balance. Furthermore, career proactivity was relatively more important for subjective financial success in cultures with high in‐group collectivism, high power distance, and low uncertainty avoidance. For work‐life balance, career proactivity was relatively more important in cultures characterized by high in‐group collectivism and humane orientation. Our findings underline the need to treat subjective career success as a multidimensional construct and highlight the complex role of national culture in shaping the outcomes of career proactivity.  相似文献   
453.
浅谈宁夏古王高速公路绿化   总被引:2,自引:0,他引:2  
张湧  张淑娥  兰剑 《交通环保》2003,24(3):15-17
在阐述了宁夏古王高速公路路域自然地理,高速公路绿化的功能和作用,以及高速公路绿化原则的基础上,具体论述了古王高速公路绿化的方法。  相似文献   
454.
A case of mosaicism of trisomy 15, with two-thirds of the cells trisomic, was detected at 12 weeks of gestation in amniotic fluid cell cultures obtained with the filtration technique. Ultrasound examination at 13 weeks showed a nodule protruding into the amniotic cavity which was speculated to be remnants of a co-twin, causing the trisomic cell line. At 20 weeks of gestation, a malformation scan (level III) was normal, but supplementary fetal echocardiography revealed a severe cardiac defect (mitral atresia and a ventricular septal defect). Fetal lymphocytes obtained by cordocentesis showed trisomy 15 mosaicism, but only in 5 per cent of the mitoses. After termination, the same percentage of trisomy 15 mosaicism was found in cells from skin and tendon as in the original early amniocentesis. No sign of earlier twinning was found in the placenta or membranes. We conclude that mosaicism in early amniotic fluid obtained by the filter technique in this case reflected the true karyotype accurately and that supplementary echocardiography added significantly to the interpretation of the clinical implications.  相似文献   
455.
A case of right-sided congenital diaphragmatic hernia was detected at 33 weeks of gestation. Fetal echocardiography revealed the presence of an intrapericardial mass (3.5 × 3 cm) localized at the right of the heart and surrounded by a massive pericardial effusion. This mass had the same echogenicity as the liver, with which it shared vascular channels. The diagnosis of right diaphragmatic hernia with protrusion of hepatic tissue into the pericardial sac and secondary pericardial effusion was made and confirmed after birth. In utero diagnosis of this anomaly enabled correct assessment of perinatal risk, and optimal fetal and infant management.  相似文献   
456.
The whelk Buccinum undatum L. in the northern Gulf of St. Lawrence has a distinct annual reproductive cycle. The ovary and pallial oviduct of the female, and the seminal vesicle of the male, show parallel development, whereas the testis has an inverse cycle. Thus, at the end of winter when the ovary, pallial oviduct and seminal vesicle reach maximal size, the testis is small and undeveloped, whereas the reverse situation occurs in summer. This is the first report of a totally inverse relationship between the ovary and testis for a marine invertebrate. This unusual pattern is due to the long-term storage of sperm in the seminal vesicle of the male prior to copulation. There is no resting period at the end of oogenesis, but rather renewed ovarian development starts shortly after gamete release. By contrast, in the testis after transfer of sperm to the seminal vesicle at the end of spermatogenesis, there is a distinct period of phagocytosis. Mating begins in mid-May, reaches a peak during June and terminates prior to July. Egg laying begins in late May, reaches a peak in mid-June to mid-July and can continue until late August. Examination of the incidence of individuals with food in their stomachs showed that feeding activity is maximal in late autumn through to early spring and decreases sharply coincident with the onset of breeding in late May.  相似文献   
457.
The reproductive cycle of the large brooding seastar Leptasterias polaris Müller and Troschel was examined over an 18-month period in the St. Lawrence Estuary, Québec, Canada. There is a distinct annual cycle with spawning over several months in the autumn. The female has an unusual cycle in that the ovary only slightly decreases in size during spawning, and the size structure of the oocyte population is remarkably stable throughout the year. The major annual change observed in the oocyte population is the development of a small number of 600-to 800- oocytes prior to spawning and their loss during spawning. This stability, combined with the lack of evidence of phagocytosis, suggests that oocyte development takes place over many years. By contrast, the developmental cycle of the testis is similar to that of most echinoderms. The large reservoir of oocytes probably guarantees a steady annual recruitment, and brooding during the winter probably minimizes metabolic costs for the female and ensures the release of the juveniles when conditions are favourable in the spring and summer.  相似文献   
458.
An experimental study was conducted in order to determine the relationship of nitric oxide (NO) consumption to water-filled pore space in soil. A test system that included the capability to blend gases, test soil samples, and analyze off-gases was used to conduct the study. The experimental set consisted of three replicates at five different levels of soil water content and three different levels of soil nitrogen in a sandy loam soil: unamended soil, soil fertilized at 56.2 kg N per ha (50 lb N acre(-1)), and soil fertilized at 112.3 kg N per ha (100 lb N acre(-1)). The average NO consumption rates were 7.1x10(-13) g-NO cm(-3) soil, 3.5x10(-11) g-NO cm(-3) soil, and 1.5x10(-10) g-NO cm(-3) soil, respectively.  相似文献   
459.
The ChemChar reverse-burn gasification process was evaluated to determine its feasibility for use in the regeneration of spent activated carbon. This non-incinerative, thermochemical gasification process pyrolyzes the sorbed wastes and restores the sorptive capacity of the carbon in one energy-efficient step. The effects of moisture and supplemental fuel addition on regeneration were determined with a laboratory-scale reactor and a flow-through assay method was developed for determining regeneration effectiveness. The process produces good quality regenerated carbon simply and inexpensively with a minimum of carbon loss. Carbons can be regenerated several times and the method is non-polluting.  相似文献   
460.
Objective: The objective of this study was to obtain information about the current knowledge and habits of parents who transport children in cars in Brazil.

Methods: A cross-sectional survey was conducted using specifically designed self-report questionnaires to parents of children attending a private pediatric office in a town in southwest Brazil. Data were collected regarding children's age, gender, height, and weight and possession of an automobile child restraint system (CRS), its type, frequency and adequacy of use, and reasons for not possessing or not using the devices. Parents were asked whether their cars were equipped with airbags and about the use of the restraints in seats with airbags.

Results: We interviewed parents of 293 children transported in cars who met the criteria for use of a CRS. Children were younger than 1 year in 15.3% of the cases, between 1 and 4 years in 38.6%, and older than 4 in 46.1%. Cars were equipped with CRS in 78.5% of the cases, but in only 58% of the cases was the device proper for child's age and adequately installed in the seat. Among owners of the devices, 84.3% reported that they always used it. Reasons for infrequency were forgetting the device at home or in another car (6.4%), the child disliking the device (3.2%), or the false impression that the child was grown enough not to use it (3.2%)l 87.1% did not justify why they did not always use the CRS. Considering type of CRS, correct installation of the seat, and frequency of use, only 44.4% of children under 1 year, 69.9% of those 1 to 4 years, and 52.6% over age 4 were protected. Only 28.6% of the parents knew that children should never be positioned in a seat with active airbags.

Conclusion: Considering appropriateness for age, correctness of installation (in the back seat in the correct orientation), and frequency of use, only 50.85% (149/293) of the children were reported as always protected with a CRS. Children between 1 and 4 years were more likely to always use a CRS in this Brazilian survey. We were also able to identify an important gap in the knowledge about airbags among parents. Further efforts are needed to correct those distortions.  相似文献   

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