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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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The importance of combustion processes as a source of substances with estrogenic activity in the environment was investigated. Wood (nontreated and treated with wood preservatives), barbecue charcoal, meat, and kitchen waste were combusted in a laboratory-scale incinerator. Flue gas emissions (particulates and gaseous pollutants) were trapped in polyurethane foam cartridges. The cartridges were subjected to Soxhlet extraction and part of the extracts redissolved in dimethylsulfoxide (DMSO) for analyses of estrogenic activity by means of the yeast-based human estrogen receptor (hER) bioassay. A synthetic estrogen, 17-alpha-ethinylestradiol (EE2), was used as the reference estrogenic compound. Part of the extracts was analyzed for the 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs). Estrogenic compounds in the flue gas (wood) were as high as 234 +/- 25 ng m(-3) EE2 equivalent compared with 27 to 81 ng m(-3) EE2 equivalent in flue gas from combustion of barbecue charcoal. Concentrations of polycyclic aromatic hydrocarbons in both flue gas streams were in the range of 21,000 +/- 2000 and 240 +/- 110 ng m(-3), respectively. In general, the concentrations of EE2 equivalent in the flue gas samples were at least a factor of 1000 lower than total PAH concentration. The EE2 levels were not related to the concentration of PAHs in any flue gas sample.  相似文献   
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For communicating data on the state of the environment to policy makers, various integrative frameworks are used, including regional integration. For this kind of integration we have developed two related ecological regionalizations, ecoregions and ecodistricts, which are two levels in a series of classifications for hierarchically nested ecosystems at different spatial scale levels. We explain the compilation of the maps from existing geographical data, demonstrating the relatively holistic, a priori integrated approach. The resulting maps are submitted to discriminant analysis to test the consistancy of the use of mapping characteristics, using data on individual abiotic ecosystem components from a national database on a 1-km2 grid. This reveals that the spatial patterns of soil, groundwater, and geomorphology correspond with the ecoregion and ecodistrict maps. Differences between the original maps and maps formed by automatically reclassifying 1-km2 cells with these discriminant components are found to be few. These differences are discussed against the background of the principal dilemma between deductive, a priori integrated, and inductive, a posteriori, classification.  相似文献   
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This paper establishes that the collection system within the recycling scheme for consumer electronics in the Netherlands has not been entirely successful in convincing consumers to hand in their used appliances by means of dedicated collection routes. Particularly regarding small appliances, consumers are persisting in their habit of discarding their appliances by means of the refuse bag/bin for regular household waste. Therefore, the current collection system has been unable to direct consumer behavior in the desired direction. Consequently, the layout of the current system is reviewed and redesigned in order to tackle this problem. This design effort applies the Triad model (behavioral model) in the analysis stage and the Morphological Chart method (design tool) in the synthesis stage, and results in a concrete proposal for a new system. Finally, the applicability of this design approach beyond the specific circumstances of the case study presented in this paper is discussed. This case represents only one example of the broader, worldwide challenge to design appropriate collection systems to direct consumer behavior in desired directions. It is argued that the approach presented in this paper could be a valuable contribution to research dealing with this challenge.  相似文献   
26.
Due to scientific interest on the one hand and political and regulatory obligations on the other hand the monitoring of ozone in the troposphere is an important issue. To this end, in Belgium as in many other countries, a fixed network of monitoring stations is operated. In order to estimate the ozone concentrations over the whole territory, a model is needed to spatially complement the sparse measurements. This paper describes the development of an interpolation scheme which is aimed at fast operational use. The model uses the population density as auxiliary data to remove a spatial trend due to titration by nitric oxide. The residuals are interpolated by kriging. As a benchmark the inverse distance weighting interpolation method is used with and without the detrending. The proposed model systematically improves the interpolation and makes a significant difference when estimating human exposure to ozone. It is generic in design, easy to implement and flexible to changes in the monitoring network.  相似文献   
27.
Public debate on acceptable farm animal husbandry suffers from a confusion of tongues. To clarify positions of various stakeholder groups in their joint search for acceptable solutions, the concept of animal welfare was split up into three notions: no suffering, respect for intrinsic value, and non-appalling appearance of animals. This strategy was based on the hypothesis that multi-stakeholder solutions should be based on shared values rather than on compromises. The usefulness of such an artificial value distinction strategy was tested in a small series of experiments. The results demonstrate that the chosen concept to distinguish between values is effective in a stakeholder context. Farmers’ views on doing good to animals appeared to be largely based on their value to prevent suffering and predominantly focused on the provision of regular care. Their priority for this value is clearly shared with other stakeholders, providing a basis for joint solutions. The concept of intrinsic value does not play a discernable role in farmers’ considerations. Based on the varying views on welfare, it can be inferred that there is a gradual rather than a principal difference between government legislation and farmers’ values, whereas public perception and acceptance of farm practices remains complicated. Distinction between value groups and focusing on a selected notion (such as no suffering) proved to be effective in bringing representatives of stakeholder groups together, but is unlikely to bridge the emotional gap between commercial farm practices and public ideals.  相似文献   
28.
The many well-publicized food scandals in recent years have resulted in a general state of vulnerable trust. As a result, building consumer trust has become an important goal in agri-food policy. In their efforts to protect trust in the agricultural and food sector, governments and industries have tended to consider the problem of trust as merely a matter of informing consumers on risks. In this article, we argue that the food sector better addresses the problem of trust from the perspective of the trustworthiness of the food sector itself. This broad idea for changing the focus of trust is the assumption that if you want to be trusted, you should be trustworthy. To provide a clear understanding of what being trustworthy means within the food sector, we elaborate on both the concept of trust and of responsibility. In this way we show that policy focused on enhancing transparency and providing information to consumers is crucial, but not sufficient for dealing with the problem of consumer trust in the current agri-food context.  相似文献   
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