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31.
This paper addresses the issue of risk from disasters occurring due to accidents in high-consequence technologies, e.g., nuclear and oil and gas. The focus is on the challenges posed to the representation and treatment of uncertainties in the assessment of such risk, given that the occurrence of such extreme disasters is extremely unlikely, and yet they occur. A general framework of analysis is proposed.  相似文献   
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Objective

To investigate whether perioperative fetal hemodynamic changes in twin-to-twin transfusion syndrome (TTTS) are associated with neurodevelopmental impairment (NDI) at two years.

Methods

Doppler parameters of three sonograms (day before, first day after and 1 week after laser surgery for TTTS) were assessed for correlation with neurodevelopmental outcome at two years (2008-2016). NDI was defined as: cerebral palsy, deafness, blindness, and/or a Bayley-III cognitive/motor developmental test-score > 2SD below the mean.

Results

Long-term outcome was assessed in 492 TTTS survivors. NDI was present in 5% (24/492). After adjustment for severe cerebral injury (present in 4%), associated with NDI were: middle cerebral artery peak systolic velocity (MCA-PSV) >1.5 multiples of the median (MoM) 1 day after surgery (odds ratio [OR] 4.96; 95% confidence interval [CI]: 1.17-21.05, P = .03), a change from normal umbilical artery pulsatility index (UA-PI) presurgery to UA-PI >p95 postsurgery (OR 4.19; 95% CI: 1.04-16.87, P = .04), a change from normal to MCA-PSV >1.5MoM (OR 4.75; 95% CI: 1.43-15.77, P = .01).

Conclusion

Perioperative fetal hemodynamic changes in TTTS pregnancies treated with laser are associated with poor neurodevelopmental outcome. Prospective research on the cerebrovascular response to altered hemodynamic conditions is necessary to further understand the cerebral autoregulatory capacity of the fetus in relation to neurodevelopmental outcome.  相似文献   
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Despite efforts at prevention through the use of preconception folic acid, spina bifida remains one of the most common congenital anomalies of the central nervous system that is compatible with life. It is, however, associated with a significant degree of lifelong morbidity. The development of open fetal surgery for myelomeningocele (MMC) has been a long process but one that serves as a model for how new procedures and technologies need to be properly evaluated before being brought into mainstream medical practice. Even so, risks and benefits need to be evaluated for each patient. The currently available studies have been carried out on a highly selected patient population where the fetal findings provided the maximum opportunity for benefit from prenatal closure of the MMC defect. There is the potential that as the surgery becomes more widely available, pressure will be brought to bear to perform surgery in cases where the likelihood for benefit is decreased and yet the risks are not. The only way to duplicate the results of the current studies is to follow the methodology and criteria that were used in the studies. This will mean that not every fetus with an MMC will be a candidate for in utero surgery. The balance of risk to benefit will continue to evolve as further technological advances are evaluated and more follow-up information is obtained. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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The role of volcanic ash as scavenger of atmospheric pollutants, in their transport and final deposition to the ground is examined. Attention is focused on polycyclic aromatic hydrocarbons (PAHs) and on particulate mercury (Hgp). The ash-fall deposits studied belong to the 2001 and 2002 eruptive activity of Mount Etna, Southern Italy, and were investigated at three (2001) and four (2002) sites downwind of the major tephra dispersal pattern. The dry deposition of mercury and PAHs was determined, and, in particular, a downward flux to the ground of PAHs (approximately 7.29 microg m(-2) per day) and mercury (750 ng m(-2) per day) was estimated in Catania from October 26 to October 28, 2002. Finally, evidence on the anthropogenic origin of PAHs scavenged from the troposphere by volcanic ash is supported by the analysis of PAH compositions in granulometrically homogeneous fractions.  相似文献   
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The widespread availability of high resolution ultrasound equipment and almost universal routine anatomy scanning in all pregnant women in the developed world has lead to increased detection of abnormalities in the fetal thorax. Already in the 1980s, large pleural effusions and significant macrocystic lesions in the fetus were easily detected on ultrasound. However, smaller lung tumours were often missed. Nowadays, fetal medicine centres receive many referrals for evaluation of fetal lung lesions, of which the most common are congenital cystic adenomatoid malformation and bronchopulmonary sequestration. Almost invariably, both the parents and the referring physicians experience anxiety after detection of large lung masses in the fetus. However, the vast majority of the currently detected fetal lung lesions have an excellent prognosis without the need for prenatal intervention. In the small group of fetuses in which the prognosis is poor, almost exclusively those with concomitant fetal hydrops and cardiac failure, several options for fetal therapy exist, often with a more than 50% survival rate. Indications, techniques, complications and outcomes of these interventions will be described in this review. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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As a nontolerant plant to a large number of toxic compounds, Arabidopsis thaliana is a suitable model to study regulation of genes involved in response to heavy metals. Using a cDNA-microarray approach, we identified some ABC transporters that are differentially regulated after cadmium treatments, making them putative candidates for being involved in Cd sequestration and redistribution in plants. Regarding yeast and fission yeast, in which Cd is able to form complexes either with glutathione (GSH) or phytochelatins (PC) subsequently transported into vacuoles via ABC transporters, it is also very likely that some plant ABC transporters are able to transport GS(2)-Cd or PC-Cd complexes into subcellular compartments or outside of the cell. The characterization of such transporters is of great interest for developing molecular biology approaches in phytoremediation.  相似文献   
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