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211.
The fate of 14C-labelled formulated parathion-methyl was investigated for 24 h after application to French beans in a laboratory chamber, where the air temperature and air humidity fluctuations as measured outdoors during a day in August 1993 could be simulated. The wind velocity directly above the plant stand and the radiation intensity could also be simulated with slight restrictions. Under these conditions, 65.9 % and 65.3 % of the A.I. applied volatilized and were directly determined in air samples in two experiments carried out under identical conditions. 28.9 % and 27.8% were determined after 24 h on the plants, only a part of this radioactivity still representing unchanged parathion methyl. The recovery of the radioactivity applied was 94.8 % and 93.1 %, respectively in the two experiments.  相似文献   
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With the increased use of invasive fetal procedures, the number of women facing post-procedure membrane rupture is increasing. Here we review the use of platelets and fresh frozen plasma for sealing iatrogenic fetal membrane defects by describing the mechanisms of action of the amniopatch procedure as well as published experience. In cases of iatrogenic preterm pre-labour rupture of the membranes, amniopatch effectively seals the fetal membranes in over two-thirds of cases. There is a risk of 16% of in utero fetal death, which may occur at varying intervals from the procedure and often for unknown reasons. Amniopatch has also been used as a treatment of chorionic membrane separation. In summary, current experience suggests that in cases of early onset but persistent amniotic fluid leakage following an invasive fetal procedure, amniopatch is an option. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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Flue gas purification is a necessary method to avoid emission of sour gases like SOx and NOx into the environment. Another important aspect is the zero CO2 emission from coal-fired power plants. Oxyfuel technology is one of the processes to reach this goal. LINDE KCA Dresden in cooperation with Vattenfall Europe is operating a pilot plant producing liquefied CO2. Product specification and material requirements make flue gas purification for the removal of SOx and NOx unavoidable. The new oxyfuel technologies offer new process conditions for flue gas purification which are not available at atmospheric conditions.At Linde laboratories, catalytic and non-catalytic DeNOx and DeSOx processes have been screened for oxyfuel application. After first feasibility studies, laboratory experiments and economic evaluations, it was decided to develop a process based on wet scrubber systems to remove NOx from flue gas, simultaneously producing ammonia nitrites which can be thermally decomposed into nitrogen in a second step. After demonstration of the single process steps on laboratory scale, a pilot scrubber was erected and commissioned in 2010 at Schwarze Pumpe Oxyfuel Pilot Plant. In September 2010, the successful completion of the pilot tests demonstrated the NOx removal efficiency of this technology. The data from the pilot plant tests have been used to finalise a kinetic model describing the NOx absorption behaviour regarding NOx removal rate and nitrite selectivity for demonstration of plant scale up. This DeNOx-process is now marketed under the name “LICONOX”.  相似文献   
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A study was initiated to ascertain whether gaseous air pollutants can influence gastric secreto-motor activities. The investigation was conducted to determine the effect of various exposures to S02, N02, CO, and 03 on gastric motor activity of the conscious unrestrained rat by means of a chronic intragastric bajloon. Tfie effects produced upon gastric secretory volume and total titratable acid secretion produced by these gases were also studied in rats which were pylorus-ligated subsequent to exposure. Rats exposed to 1 ppm S02 for 5 days, 60 ppm CO for 2 hours, 0.5 ppm N02 for 2 hours, or 0.25 ppm 03 for 2 hours showed no change while there was gastric inhibition at 300 ppm S02 for 2 hours, 1400 ppm CO for 1 hour, 26 ppm N02 for 2 hours and 1.5 ppm 03 for 2 hours. In most instances following chamber flushing recovery was complete within minutes. To evaluate the site and nature of stimulation, rats were also exposed to oil of mustard, benzaldehyde, hydrogen peroxide, amyl acetate, and “Old Spice” after sh ave lotion. Saturated dental paper points were introduced without obstruction into tracheal and retro-nasal cannulae. Oil of mustard but not benzaldehyde or amyl acetate inhibited gastric motility only when applied to the trachea. In general, the drop in activity was immediate and proportional to the degree of exposure. Nasal irritation was ineffective in eliciting the response. The experimental results lead to the following conclusions: 1) Toxic levels of these gases are associated with an inhibition of gastric motility that is not produced by .exposure of the nasal passages alone to the gases. 2) Toxic levels of these gases produced no demonstrable effect upon either total gastric acid secretion or total secretory volume. These findings tend to confirm earlier observations of an association between exposure to toxic concentrations of S02 and loss of gastric tone in the rodent stomach.  相似文献   
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Understanding technological change provides a crucial basis for governing sustainability transitions. In this paper we present an analysis of technological change using the example of Swiss thermal waste processing. In recent years, increased concerns about the low quality of residues from grate-firing systems led to the examination of alternative technologies. Yet despite clear indications of a potential better performance with respect to residue quality, none of these alternatives has been adopted. Based on a two-stage knowledge integration among 15 leading experts, in a retrospective analysis we identified factors that have significantly affected technological change in Swiss thermal waste processing. These factors were then related to three technological options representing different types of technological change, i.e., from incremental improvements of the existing to the implementation of a new technology. The results indicate that technological change is currently in a technological lock-in and provide detailed insights on the causes. The lock-in results in the step-wise further development of the status quo grate-firing system despite its limitations for improving the residue qualities. Almost all factors (legal, economic, societal, technological) of the existing ‘thermal waste management’ system have been well adapted to the cost- and energy-efficient grate-firing technology, blocking innovative technologies from entering the Swiss market. In addition, pressures from the context, e.g., societal pressure related to landfill risks, have not been strong enough to promote non-incremental change.  相似文献   
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Sacrococcygeal teratoma (SCT) is one of the most common tumors in newborns with a birth prevalence of up to 1 in 21 700 births. Routine fetal anomaly screening programs allow for prenatal diagnosis in many cases. Fetal ultrasound with Doppler evaluation and more recently magnetic resonance imaging may be used to document the extent of the tumor as well as identifying the population at risk for serious fetal complications. Rapidly growing SCT and highly vascularized tumors are more likely to have hemodynamic repercussions. Fetal hydrops is usually considered as a poor prognostic marker and a potential indicator for fetal intervention. Newborns with SCT require stabilization prior to early surgical resection. In case of malignancy additional chemotherapy may be required. SCT may result in significant morbidity, either directly or as a consequence of surgical therapy. Careful postnatal follow-up is required for timely identification and treatment of complications as well as recurrence. This paper aims to review the perinatal management of this condition. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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