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211.
212.
The present report describes two fetuses, one female and one male, with thus far undescribed skeletal malformations. The mother was a gravida 2, para 0. Both pregnancies were terminated in the second trimester because of multiple congenital anomalies diagnosed ultrasonographically resembling a short rib-polydactyly syndrome. Both fetuses were found to have postaxial hexadactyly of the hands and feet, marked bilateral campomelia of the forearm and shank bones, and a Dandy–Walker cyst. In addition, the fourth ventricle was dilated in the first sibling and the second sibling had an inverse intestinal malrotation. A literature search failed to reveal similar observations. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
213.
The body of information presented in this paper is directed to those engineers and maintenance personnel involved in the operation of mobile-bed scrubbers. Materials tests were performed on three specimens of austenitic stainless steel to determine the possible causes of grid rod failure in a mobile-bed scrubber controlling particulate emissions from a pulverized-coal-fired, steam-electric generating station. These three specimens were successively placed in an Instrom universal testing machine and loaded in tension until rupture occurred. The results of these tests, in addition to other supporting data, were used in an attempt to determine the cause of the grid rod failure during scrubber operation. It was determined that the grade of stainless steel used, the scrubber water quality, and certain operational problems could be causes of premature failure.  相似文献   
214.
The secondary plant metabolite 6-methoxy-2-benzoxazolinone (6-MBOA) is abundant in vegetative parts of monocotyledons emerging in spring. This grazing protective has been shown to promote gonadal growth and, thus enable precise alignment of reproductive activity with favorable environmental conditions in a variety of seasonally breeding rodent species. Feeding and breeding ecology make the Djungarian hamster (Phodopus sungorus) a potential candidate using 6-MBOA as an acute environmental cue to optimize reproductive timing when photorefractoriness induces reproductive recrudescence. Therefore, four different experiments were designed to examine whether the hamsters’ reproductive organs are responsive to oral 6-MBOA administration under different photoperiodic conditions. Only under a long photoperiod, we found a slight increase in uterine weights. In a short photoperiod, 6-MBOA-treated hamsters showed a slight body weight gain without a change in uterine weights. However, these marginal effects are likely not to be of ecophysiological significance for reproductive timing. The results are in agreement with the common view that the annual changes in photoperiod length are not only the predominant environmental cue for Djungarian hamsters, but are also sufficient to synchronize reproductive efforts with favorable breeding conditions in highly predictable climates like the continental Asian steppes.  相似文献   
215.
The spiny forest of southwestern Madagascar is the driest and most unpredictable region of the island. It is characterized by a pronounced seasonality with high fluctuations in ambient temperature, low availability of food, and a lack of water during the cool dry season and, additionally, by changes in environmental conditions between years. One of the few mammalian species that manages to inhabit this challenging habitat is the reddish-gray mouse lemur (Microcebus griseorufus). The aim of our study was to determine whether this small primate uses continuous hibernation as an energy saving strategy, and if so, to characterize its physiological properties. We measured skin temperature of 16 free-ranging individuals continuously over 3 months during the cool dry season using collar temperature data loggers. Prolonged hibernation was found in three mouse lemurs and was not sex dependent (one male, two females). Skin temperature of hibernating individuals tracked ambient temperature passively with a minimum skin temperature of 6.5°C and fluctuated strongly each day (up to 20°C), depending on the insulation capacity of the hibernacula. Individuals remained in continuous hibernation even at an ambient temperature of 37°C. The animals hibernated continuously during the dry season, and hibernation bouts were only interrupted by short spontaneous arousals. The study emphasizes that hibernation is an important measure to counter environmental challenge for more tropical species than previously thought, including primates. It furthermore provides evidence that tropical hibernation is functionally similar among tropical species.  相似文献   
216.
Environmental Science and Pollution Research - Activated carbon (AC) can be used for the removal of emerging contaminants (e.g., drugs) in water and wastewater treatment plants. In the present...  相似文献   
217.
Declines of species in fragmented landscapes can potentially be reversed either by restoring connectivity or restoring local habitat quality. Models fitted to snapshot occupancy data can be used to predict the effectiveness of these actions. However, such inferences can be misleading if the reliability of the habitat and landscape metrics used is unknown. The only way to unambiguously resolve the roles of habitat quality and metapopulation dynamics is to conduct experimental reintroductions to unoccupied patches so that habitat quality can be measured directly from data on vital rates. We, therefore, conducted a 15-year study that involved reintroducing a threatened New Zealand bird to unoccupied forest fragments to obtain reliable data on their habitat quality and reassess initial inferences made by modeling occupancy against habitat and landscape metrics. Although reproductive rates were similar among fragments, subtle differences in adult survival rates resulted in λ (finite rate of increase) estimations of <0.9 for 9 of the 12 fragments that were previously unoccupied. This was the case for only 1 of 14 naturally occupied fragments. This variation in λ largely explained the original occupancy pattern, reversing our original conclusion from occupancy modeling that this occupancy pattern was isolation driven and suggesting that it would be detrimental to increase connectivity without improving local habitat quality. These results illustrate that inferences from snapshot occupancy should be treated with caution and subjected to testing through experimental reintroductions in selected model systems.  相似文献   
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