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111.
Single copies of tiny chromosome fragments, appearing either as single or as double minutes, were observed in a high frequency in amniotic fluid cultures of five mothers who underwent prenatal testing because of advanced age. In four cases, the minutes had arisen de novo. The minutes were later confirmed in fetal skin following termination of pregnancy in one case; in another, in cord blood following the birth of a normal boy; and in the third, in peripheral blood of a normal 3-year-old girl. In the fourth case, the minutes were not confirmed in cord blood following the birth of a normal boy. A follow-up chromosome study of the baby boy in the fifth case was not possible but the minutes were maternally transmitted.  相似文献   
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During a period of heavy ranfall in Essex, Connecticut, on 4th and 5th June 1982, dams in the town along the Fall River were monitored for signs of braks. The observation of water spilling over one of teh dams at 10 p.m. in 5th June ld to the decision to evacuate community rsidents. The notification and avacuation process was conducted by the cvolunteer fire department over a two-hour periopd. At 12.30 a.m 6th June, the upper dam on the Fall River gave way, rsulting in a rapidly moving floodwave which sequentially destroyed four additional dams along the river. Although there was extensive property damage, gthere were no serious injuries and no deaths. The responsible actons of the town officials in monitoring the dams during the period of heavy rainfall permitted the evacuation order to be given in sufficient time to evacuate the residnts. The success of the evacuation was the result of good communication, trust, and co-operation between town officials and the community.  相似文献   
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Sex chromosome aneuploidy (SCA), when detected in amniocentesis, is usually an unexpected result of a test carried out for another purpose. For most SCAs, the prognosis is milder and less predictable than trisomy 21, and therefore parents are faced with a difficult decision regarding the option of pregnancy termination. While studies from Europe and the USA report a declining trend in termination rates for SCA, our local experience is different. During the period 1989–1998, we diagnosed 60 SCA (including mosaics) in 20 106 amniocenteses (0.29%) and 48 (80%) of these pregnancies were terminated, a significantly higher proportion than has been reported in Europe and the USA. The present study shows that the difference between our experience and others' may be related to differences in cultural norms and values. Thirty women were interviewed, of whom 23 terminated and seven continued the pregnancy. Interview analyses showed that the main reason behind the decision to terminate the pregnancy was associated with the parents' fear of non-specific abnormality of the child, and concerns about abnormal sexual development. Although genetic counseling practised in our center aims to be non-directive, 56% of the women reported that the counseling was either directive towards termination, or that they at least felt that the counselor's attitude was pro-termination. Most women (93%) reported themselves as having come to terms with their decision. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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When both parents provide offspring care, equal sharing of costly parental duties may enhance reproductive success. This is crucial for longlived species, where increased parental effort in current reproduction profoundly affects future reproduction. Indication of reproductive value or willingness to invest in reproduction may promote matching responses by mates, thus reducing the conflict over care. In birds with biparental care, blue-green eggshell color may function as a signal of reproductive value that affects parental effort, as predicted by the signaling hypothesis of blue-green eggshell coloration. However, this hypothesis has not been explored during incubation, when the potential stimulus of egg color is present, and has been little studied in longlived birds. We experimentally studied if egg color affected incubation patterns in the blue-footed booby, a longlived species with biparental care and blue eggs. We exchanged fresh eggs between nests of the same laying date and recorded parental incubation effort on the following 4 days. Although egg color did not affect male effort, original eggshell color was correlated with pair matching in incubation. Exchanged eggshell color did not affect incubation patterns. This suggests that biliverdin-based egg coloration reflects female quality features that are associated with pair incubation effort or that blue-footed boobies mate assortatively high-quality pairs incubating more colorful clutches. An intriguing possibility is that egg coloration facilitates an equal sharing of incubation, the signal being functional only during a short period close to laying. Results also suggest that indication of reproductive value reduces the conflict over care.  相似文献   
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OBJECTIVE: Despite the potential benefits that fleet vehicle purchase decisions could have on road safety, the role that vehicle safety plays in fleet managers' purchase decisions is poorly understood. METHODS: In this study, fleet managers from Sweden and Spain completed a questionnaire regarding the importance of vehicle safety in the new vehicle purchase/lease process and the importance that is placed on safety options/features relative to other convenience and comfort features. RESULTS: The findings of the current study suggest that vehicle safety is generally not the primary consideration in the vehicle purchase process and is consistently outranked by factors such as price and dependability/reliability. For example, when asked to indicate the vehicle factors that are included in their company's criteria for purchasing/leasing a new vehicle, fleet managers from both Sweden and Spain were more likely to list the vehicle's price, reliability, running costs, size, and fuel consumption than the vehicle's safety (defined as the vehicle's EuroNCAP rating/other safety reports). In addition, the findings of this study suggest that the importance of vehicle safety did not differ across the two countries. For example, there was no significant difference in the proportion of fleet managers who indicated that EuroNCAP ratings were part of their official policy across the two countries. CONCLUSION: The findings highlighted the need to educate fleet managers about vehicle safety in the new vehicle purchase/lease process. In addition, vehicle safety information, such as EuroNCAP results or other crash test results need to be promoted more widely and effectively so that they play a more prominent role in their new vehicle choices.  相似文献   
118.
OBJECTIVE: With increasing rates of survival associated with traffic crashes, a shift to understand the consequences of injury has risen to prominence. This prospective cohort study set out to examine general health status and functional disability at 2 months and 6-8 months post-crash. METHODS: Participants were otherwise healthy adults aged 18-59 years admitted to hospitals, excluding those with moderate-severe head injury and spinal cord injury. Sixty-two adults completed interviews prior to discharge and at 2 months and 8 months post-discharge. RESULTS: By 8 months post-crash, 89 percent had resumed employment and or study, two thirds rated the resolution of their medical problems to be excellent (14.5 percent) or good (53 percent), and 82 percent were considered to be fully self-sufficient with respect to activities of daily living. Despite this, results from the SF-36 indicated significant reductions in health status at 2 and 8 months post-crash relative to pre-crash health, with domain scores up to 26 percent lower than pre-crash scores, while assessment of activities of daily living indicated residual functional disability at both follow-up times. Self-reported pain was higher for both males and females at both follow-up times compared with pre-crash self-reported pain. CONCLUSION: This study demonstrated significant, ongoing loss of health-related quality of life and impairment associated with injuries sustained in road crashes, highlighting the need for continuing care post-discharge to facilitate a rapid return to optimal health.  相似文献   
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On the nature of barriers to climate change adaptation   总被引:1,自引:0,他引:1  
Considerable barriers can emerge in developing and implementing climate change adaptation strategies. Understanding the nature of barriers to adaptation is important so as to find strategic ways of dealing with them. However, our current understanding is limited and highly fragmented across the academic community. This paper aims to bring some conceptual convergence in these debates by applying a systematic review method to assess the current state of knowledge on barriers to adaptation in the peer-reviewed literature. The review results show that: (1) Barriers to adaptation have hardly been defined in the literature and no clear indicators exist so as to identify and assess them systematically. (2) An impressive number of barriers have been reported, but the list of possible barriers is seemingly endless. (3) The most frequently reported barriers relate to the institutional and social dimensions of adaptation. (4) Barriers are identified as configurations of climate and non-climate factors and conditions that emerge from the actor, the governance system, or the system of concern. (5) Barriers are mainly studied in developed countries with a strong focus on water-related domains. (6) The majority of studies on barriers use small-n inductive case approaches while comparative studies across different contexts are limited. (7) Although interventions to overcome barriers are recommended by most studies, empirical studies on interventions are scarce. We present further conceptual clarification and a more precise definition of barriers to adaptation. We conclude that future research should go beyond asking the questions ‘if’ and ‘which’ barriers to adaptation exist and begin asking ‘how’ and ‘why’ barriers emerge.  相似文献   
120.
Environmental Geochemistry and Health - This study describes spatiotemporal patterns from October 2015 to September 2016 for PM2.5 mass and carbon measurements in rural (Kosmarra), urban (Raipur),...  相似文献   
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