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21.
Fetal lymphangiomas are rare congenital anomalies of the lymphatic system most commonly presenting in the head and neck. Cystic abdominal lymphangiomas are more rare with only a few cases reported prenatally. We report a case of a prenatally detected abdomino-perineal lymphangioma that mimicked the more fatal prenatally detected sacrococcygeal teratoma (SCT), which resulted in one caregiver suggesting termination of the pregnancy. This case demonstrates the importance of carefully considering the differential diagnosis of fetal abdomino-perineal masses when counseling parents. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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The risk associated with storage of carbon dioxide in the subsurface can be reduced by removal of a comparable volume of existing brines (e.g. Buscheck et al., 2011). In order to avoid high costs for disposal, the brines should be processed into useful forms such as fresh and low-hardness water. We have carried out a cost analysis of treatment of typical subsurface saline waters found in sedimentary basins, compared with conventional seawater desalination. We have also accounted for some cost savings by utilization of potential well-head pressures at brine production wells, which may be present in some fields due to CO2 injection, to drive desalination using reverse osmosis. Predicted desalination costs for brines having salinities equal to seawater are about half the cost of conventional seawater desalination when we assume the energy can be obtained from excess pressure at the well head. These costs range from 32 to 40¢ per m3 permeate produced. Without well-head energy recovery, the costs are from 60 to 80¢ per m3 permeate. These costs do not include the cost of any brine production or brine reinjection wells, or pipelines to the well field, or other site-dependent factors.  相似文献   
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Adult development is becoming a critical component of an organization's effectiveness in our rapidly changing world (Torbert, 1987). While transitions in adulthood have been shown to be inevitable and patterned, they do not necessarily result in personal growth. In this exploratory study, data were collected from 64 men and women experiencing midlife transitions. Several factors were identified (scope of transition, progression through a transition sequence, ego development, inner directedness, and commitment to learning) which enabled growth during the midlife transition in the form of a personal paradigm shift. Positive emotional tone as well as enthusiasm for career were found to be consequences of these paradigm shifts. Implications for organizations are discussed.  相似文献   
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-- An environmental assessment of the transformation and transport pathways of hexachlorocyclopentadiene (hex) in simulated aquatic ecosystems is presented. Hydrolytic and photolytic disappearance rate constants in distilled and natural waters and in sediment-water systems are given. Sediments in defined sediment-water systems do not significantly affect the disappearance rate constants, compared to distilled water values, for the hydrolytic and photolytic processes. Water solubility, octanol/water partition coefficient, and vapor pressure for hex are also reported and compared with literature values. Fate and transport assessment using an evaluative model indicates that hex will not likely reach substantial steady-state concentrations in the various compartments of the simulated ecosystems. The results also indicate that photolysis and, to a lesser extent, hydrolysis are the predominant degradation processes; export via the water column is the predominant transport process.  相似文献   
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Beneficial and environmentally safe recycling of flue gas desulfurization (FGD) products requires detailed knowledge of their chemical and physical properties. We analyzed 59 dry FGD samples collected from 13 locations representing four major FGD scrubbing technologies. The chemistry of all samples was dominated by Ca, S, Al, Fe, and Si and strong preferential partitioning into the acid insoluble residue (i.e., coal ash residue) was observed for Al, Ba, Be, Cr, Fe, Li, K, Pb, Si, and V. Sulfur, Ca, and Mg occurred primarily in water- or acid-soluble forms associated with the sorbents or scrubber reaction products. Deionized water leachates (American Society for Testing and Materials [ASTM] method) and dilute acetic acid leachates (toxicity characteristic leaching procedure [TCLP] method) had mean pH values of >11.2 and high mean concentrations of S primarily as SO(2-)4 and Ca. Concentrations of Ag, As, Ba, Cd, Cr, Hg, Pb, and Se (except for ASTM Se in two samples) were below drinking water standards in both ASTM and TCLP leachates. Total toxicity equivalents (TEQ) of dioxins, for two FGD products used for mine reclamation, were 0.48 and 0.53 ng kg(-1). This was similar to the background level of the mine spoil (0.57 ng kg(-1)). The FGD materials were mostly uniform in particle size. Specific surface area (m2 g(-1)) was related to particle size and varied from 1.3 for bed ash to 9.5 for spray dryer material. Many of the chemical and physical properties of these FGD samples were associated with the quality of the coal rather than the combustion and SO2 scrubbing processes used.  相似文献   
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This study examines the relationship between violation of an employee's psychological contract and civic virtue behavior. A psychological contract is a set of beliefs regarding mutual obligations between employee and employer. One hundred twenty-six MBA alumni were surveyed at the time of hire (T1), and after 18 months (T2) and 30 months (T3) on the job. When employees felt that their employers had failed to fulfil employment obligations at T2, they were less likely to engage in civic virtue behavior at T3. There was evidence that this relationship was partly mediated by trust. These findings have implications for research on OCB and for managers seeking to maintain employee citizenship behavior.  相似文献   
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This paper presents a ranked set sample allocation procedure that is optimal for a number of nonparametric test procedures. We define a function that measures the amount of information provided by each observation given the actual joint ranking of all the units in a set. The optimal ranked set sample allocates order statistics by maximizing this information function. This paper shows that the optimal allocation of order statistics in a ranked set sample is determined by the location of the mode(s) of the underlying distribution. For unimodal, symmetric distributions, optimal allocation always quantifies the middle observation(s). If the underlying distribution with cdf F is a multi-modal distribution with modes , then the optimal allocation procedure quantifies observations at in a set of size m. We provide similar results for unimodal, asymmetric distributions. We also propose a new sign test which considers the relative positions of the quantified observations from the same cycle in a ranked set sample. The proposed sign test provides improvement in the Pitman efficiency over the ranked set sample sign test of Hettmansperger (1995). It is shown that the information optimal allocation procedure induced by Pitman efficiency is equivalent to the optimal allocation procedure induced by the information criteria. We show that the finite sample distribution of the proposed test based on this optimal design is binomial.  相似文献   
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