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The fetal inflammatory response syndrome (FIRS) describes a state of extensive fetal multi organ involvement during chorioamnionitis, and is associated with grave implications on perinatal outcome. The syndrome has been linked to the preterm parturition syndrome and is associated with inflammation/infection processes in most of the fetal organs. The fetal thymus, a major organ in the developing immune system involutes during severe neonatal disease and has been shown to be smaller in fetuses with FIRS. Various methods for imaging of the fetal thymus and measurement are described. Currently the only method to diagnose FIRS prenatally is through amniocentesis. We suggest that women who are admitted with preterm labor with intact membranes and those with PPROM should have a detailed sonographic examination of the fetal thymus as a surrogate marker of fetal involvement in intrauterine infection/inflammation processes. © 2015 John Wiley & Sons, Ltd. 相似文献
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Three low-volume mini-sprinklers were tested for their efficacy to strip trichloroethylene (TCE) and tetrachloroethylene (PCE) from water. Deionized water spiked with TCE and PCE was pumped for approximately 1 h at 0.19 to 0.21 MPa (28 to 30 lb in(-2)) through a mini-sprinkler supported on top of a 1.8-m-tall riser. Water was collected in collection vessels at 0.61 and 1.22 m above the ground on support columns that were spaced at 0.61-m intervals from the riser base, and samples were composited per height and distance from the riser. Overall, air-stripping reduced dissolved concentrations of TCE and PCE by 99.1 to 100 and 96.9 to 100%, respectively, from mean influent dissolved concentrations of 466 to 1675 microg L(-1) TCE and 206 to 940 microg L(-1) PCE. In terms of mass removed, the mini-sprinklers removed TCE and PCE at a rate of approximately 1400 to 1700 and 700 to 900 microg L(-1), respectively, over a 1-h test period. Mini-sprinklers offer the advantages of (i) easy setup in series that can be used on practically any terrain; (ii) operation over a long period of time that does not threaten aquifer depletion; (iii) use in small or confined aquifers in which the capacity is too low to support large irrigation or purging systems; and (iv) use in forests in which the small, low-impact droplets of the mini-sprinklers do not damage bark and in which trees can help manage (via evapotranspiration) excess waste water. 相似文献
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Susan L. Murray Yvette L. Simon Hong Sheng 《Journal of Loss Prevention in the Process Industries》2011,24(6):774-779
Workers in the chemical industry are often required to wear protective suits while performing tasks. While these suits can be life saving, they increase the difficulty and discomfort faced by the wearer. This research explores the performance of individuals wearing the highly cumbersome Level A suit. The suits are heat-retentive and can cause fatigue that affects performance by increasing response time and decreasing accuracy. Members of Missouri’s Civil Support Team (CST) served as subjects for this research. They conducted fine and gross motor tests. Their completion time and accuracy were evaluated both out-of-suit and in-suit for the Level A chemical protective suits.A t-test was conducted to evaluate the effect of the Level A suits on performance. Results showed a significant increase in completion time and errors for gross motor tasks. This type of task had up to a 103% increase in time required and up to a 34% decrease in accuracy. The suit’s impact on fine motor skill was also significant, but to a lesser extent. Repeated measures test was performed to evaluate any potential time-in-suit effect. A decrease in mean task completion time was observed for some of the tasks. There was a corresponding decrease in accuracy but no consistent time-in-suit effect was identified.The results indicate the need for care when designing procedures and equipement to be used by humans wearing restrictive PPE. It is important to take human limitations into consideration in the design phase in order to decrease the need for human adaptation and increase system safety. To achieve this, understanding human factors is imperative when designing equipment, tasks, or procedures for workers wearing PPE. 相似文献
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Rachael L. McEwing Roume Joelle Marc Mohlo Jean-Pierre Bernard Yvette Hillion Yves Ville 《黑龙江环境通报》2006,26(12):1110-1114
Prenatal ultrasound and magnetic resonance imaging (MRI) demonstrated a large oropharyngeal tumor, and cardiac and cranial abnormalities consistent with neurofibromatosis type 1 (NF1) in a third-trimester fetus, which were confirmed on postmortem examination. Sonographic features of NF1 are generally nonspecific; MR examination provided significant additional information, facilitating prenatal diagnosis. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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高密度微阵列基因芯片技术在微生物分子生态学研究中的运用 总被引:2,自引:1,他引:1
应用基于16S rDNA 的高密度微阵列基因芯片(Microarray)技术对膜生物反应器内的微生物多样性进行研究.结果表明,膜生物反应器具有较高的微生物多样性,Microarray共检测到1 019种微生物.Proteobacteria是其中的优势种,共含有657种微生物,占总种群数量的64.5%左右.gamma Proteobacteria是Proteobacteria中的优势种,占35.8%左右,但相对含量一般并不高.beta Proteobacteria虽然种群数量稍少,但其在荧光强度最高的前25种和50种微生物中比重最大,分别占40%和36%左右.通过比较微生物的相对荧光强度,发现Clostridia是系统中的优势微生物种属.一些常见的硝化细菌如Nitrosomonadaceae、Nitrospiraceae等也具有较高的含量.Microarray作为一种实时、高效、准确的分子生物学手段,可应用于废水处理中的微生物多样性研究. 相似文献
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The intentional introduction of specialist insect herbivores for biological control of exotic weeds provides ideal but understudied systems for evaluating important ecological concepts related to top-down control, plant compensatory responses, indirect effects, and the influence of environmental context on these processes. Centaurea stoebe (spotted knapweed) is a notorious rangeland weed that exhibited regional declines in the early 2000s, attributed to drought by some and to successful biocontrol by others. We initiated an experiment to quantify the effects of the biocontrol agent, Cyphocleonus achates, on Ce. stoebe and its interaction with a dominant native grass competitor, Pseudoroegneria spicata, under contrasting precipitation conditions. Plots containing monocultures of each plant species or equal mixtures of the two received factorial combinations of Cy. achates herbivory (exclusion or addition) and precipitation (May-June drought or "normal," defined by the 50-year average) for three years. Cy. achates herbivory reduced survival of adult Ce. stoebe plants by 9% overall, but this effect was stronger under normal precipitation compared to drought conditions, and stronger in mixed-species plots compared to monocultures. Herbivory had no effect on Ce. stoebe per capita seed production or on recruitment of seedlings or juveniles. In normal-precipitation plots of mixed composition, greater adult mortality due to Cy. achates herbivory resulted in increased recruitment of new adult Ce. stoebe. Due to this compensatory response to adult mortality, final Ce. stoebe densities did not differ between herbivory treatments regardless of context. Experimental drought reduced adult Ce. stoebe survival in mixed-species plots but did not impede recruitment of new adults or reduce final Ce. stoebe densities, perhaps due to the limited duration of the treatment. Ce. stoebe strongly depressed P. spicata reproduction and recruitment, but these impacts were not substantively alleviated by herbivory on Ce. stoebe. Population-level compensation by dominant plants may be an important factor inhibiting top-down effects in herbivore-driven and predator-driven cascades. 相似文献
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Human activity causes abrupt changes in resource availability across the landscape. In order to persist in human-altered landscapes organisms need to shift their habitat use accordingly. Little is known about the mechanisms by which whole communities persist in human-altered landscapes, including the role of complementary habitat use. We define complementary habitat use as the use of different habitats at different times by the same group of species during the course of their activity period. We hypothesize that complementary habitat use is a mechanism through which native bee species persist in human-altered landscapes. To test this idea, we studied wild bee communities in agro-natural landscapes and explored their community-level patterns of habitat and resource use over space and time. The study was conducted in six agro-natural landscapes in the eastern United States, each containing three main bee habitat types (natural habitat, agricultural fields, and old fields). Each of the three habitats exhibited a unique seasonal pattern in amount, diversity, and composition of floral resources, and together they created phenological complementarity in foraging resources for bees. Individual bee species as well as the bee community responded to these spatiotemporal patterns in floral availability and exhibited a parallel pattern of complementary habitat use. The majority of wild bee species, including all the main crop visitors, used fallow areas within crops early in the season, shifted to crops in mid-season, and used old-field habitats later in the season. The natural-forest habitat supported very limited number of bees, mostly visitors of non-crop plants. Old fields are thus an important feature in these arable landscapes for maintaining crop pollination services. Our study provides a detailed examination of how shifts in habitat and resource use may enable bees to persist in highly dynamic agro-natural landscapes, and points to the need for a broad cross-habitat perspective in managing these landscapes. 相似文献