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31.
We report a patient whose chorionic villus sampling showed a nonmosaic trisomy 13 [46,XX,der(13;13)(q10;q10)]. Subsequent amniocentesis and cordocentesis showed varying percentages of abnormal cells (77 and 78% in two amniocentesis; 14% in cordocentesis) and mosaic trisomy 13 was impressed. Prenatal fetal ultrasound scanning revealed only mild structural abnormalities (echogenic cardiac foci, transient lemon head, transient skin oedema). The mother chose to continue the pregnancy. Karyotyping of the cord blood, peripheral blood, umbilical cord, urine, and chorion were performed postpartum. The process of correction appeared to exist in the placenta (indirect evidence from coexistence of trisomy 13 [46,XX,der(13;13)(q10,q10)], euploidy [46,XX], aneuploidy [46,XX,–13, +mar], and monosomy 13 [45,XX,–13] in the chorion at birth). The baby had survived beyond eight months of age at the time of submission. Few structural abnormalities except low-set ears, absence of the 12th rib, and cardiomegaly with ventricular septal defect, were noted postnatally. The growth reached 95th percentile at the age of one month. Development milestones were not delayed at serial evaluations. Her ventricular septal defect was corrected surgically at the age of six months. Karyotypes of her skin fibroblasts, blood lymphocytes, and cardiac tissue were all normal [46,XX] at the time of surgery. Difficulties of the genetic counseling are also discussed. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
32.
Biodegradation process modeling of municipal solid waste (MSW) bioreactor landfills requires the knowledge of various process reactions and corresponding kinetic parameters. Mechanistic models available to date are able to simulate biodegradation processes with the help of pre-defined species and reactions. Some of these models consider the effect of critical parameters such as moisture content, pH, and temperature. Biomass concentration is a vital parameter for any biomass growth model and often not compared with field and laboratory results. A more complex biodegradation model includes a large number of chemical and microbiological species. Increasing the number of species and user defined process reactions in the simulation requires a robust numerical tool. A generalized microbiological and chemical model, BIOKEMOD-3P, was developed to simulate biodegradation processes in three-phases (Gawande et al. 2009). This paper presents the application of this model to simulate laboratory-scale MSW bioreactors under anaerobic conditions. BIOKEMOD-3P was able to closely simulate the experimental data. The results from this study may help in application of this model to full-scale landfill operation.  相似文献   
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Total-factor water efficiency of regions in China   总被引:10,自引:0,他引:10  
Water is a limited and unevenly distributed resource in China, with the per capita amount of water resource there only about one-fourth of the world's average. However, water is an essential resource for people's lives and economic development. Over the past two decades China has seen the fruit of its rapid economic growth; nevertheless, a severe water shortage is behind this prosperous scenario and is becoming worse. Efficient water supply is certainly essential for the sustainable development of human beings. This paper analyzes water efficiency by incorporating water as an input as well as using conventional inputs such as labor employment and capital stock. An index of a water adjustment target ratio (WATR) is established from the production frontier constructed by data envelopment analysis (DEA) including water as an input. The water efficiency of regions is obtained from a total-factor framework with both residential and productive water use. A U-shape relation is discovered between the total-factor water efficiency and per capita real income among areas in China. The central area has the worst water efficiency ranking and the total adjustment amount of water used there is around three-fourths of China's total. More efficient production processes and advanced technologies need to be adopted in the central area to improve its water efficiency, especially for its productive use of water.  相似文献   
35.
Population distributions change substantially over time in major metropolitan areas. Knowledge of these variations by time of day, day of the week and other time periods can be helpful to disaster planners who need to prepare response plans to earthquakes and other disasters that will injure and kill large numbers of people. Computer graphics can display data that describe these changing population patterns in ways that can be more easily comprehended than page after page of printed numbers. Several different illustrations of 3-D population density maps drawn by the ASPEX computer program are presented. Each illustrates a guideline that can be used to prepare maps that deal with the many ways of looking at urban population density distributions and their temporal changes. Those maps can help disaster planners gain a realistic perception of population density distributions by enabling them to see what cannot be seen from the actual physical structure of a large metropolitan region.  相似文献   
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ABSTRACT: When a series of aerators are used to raise the level of dissolved oxygen in a polluted stream through instream artificial aeration augmentation, the system is governed by the basic dissolved oxygen mass balance equation with the existence of artificial aeration as its boundary conditions. A mathematical model is formulated for the optimization of the allocation of aeration capacity to each of the series of aerators subject to a limitation on total available aeration capacity. The objective function is the minimization of the sum of the squares of the aeration costs and the costs incurred by damaging or unnecessarily improving the system. The original constrained allocation problem is simplified by converting it to an unconstrained one via the use of Lagrange multiplier. A discretized dynamic programming algorithm is formulated for finding the optimal allocation policy. A typical optimal aeration capacity allocation policy and its corresponding dissolved oxygen sag profile for the illustrated numerical example is presented, and the relationship between the total available aeration capacity and Lagrange multiplier is also developed treating weighting factors as parameters.  相似文献   
38.
Huang YJ  Wang HP  Yeh CT  Tai CC  Peng CY 《Chemosphere》1999,39(13):2279-2287
Experimentally, decomposition of NO on the alkalized Pd/Al2O3 catalyst is remarkably enhanced at 825-1000 K. The enhancement in N2 yield may be due to the additional basic sites on the alkalized catalyst that can trap NO molecules. However, at T > 1000 K, due to the fact that the absorbed oxygen in subsurface or bulk of Pd was involved in the formation and desorption of oxygen molecules, yield of oxygen was enhanced.  相似文献   
39.
The roles and responsibilities of cities in CO2 mitigation have drawn increasing attention in recent years. To facilitate optimal design of effective mitigation policies, it is important for city authorities to understand the magnitudes and sources of their CO2 emissions, and their relative shares of emissions at a higher spatial level. Although several studies estimate CO2 emissions at the city level, the robustness of these estimates and their linkage to emissions at a higher level remains unclear. This kind of localized information on emissions is important for coordination of climate policies at different spatial scales. The study aims to fill a gap in understanding by building a systematic bottom-up approach for estimating urban CO2 emissions and offering a consistency check with IPCC top–down estimates. Using Taiwan as a case study, we display the geographic distribution of CO2 emissions. The significance and implications of the downscaling CO2 emissions are indicated accordingly.  相似文献   
40.
The reproductive biology of spiny lobster, Panulirus penicillatus, was studied based on 2,068 lobsters, ranging from 34.28 to 131.60 mm carapace length (CL), sampled in Taitung coastal waters from September 2003 to December 2004. The overall sex ratio approximated 1:1 (χ2 = 0.02, P > 0.05), but the monthly sex ratios in 2004 showed significant differences and males were predominant in sizes larger than 80 mm CL. Reproductive activity, assessed using histology, a gonadosomatic index and percentage of ovigerous females, indicated that the mature females could be found in every month and that the major spawning occurred from May to September. The presence of re-developing/re-ripe ovaries by month and size-specific spawning time suggest that larger mature females (>60 mm CL) spawn at least three times a year while smaller new mature females spawn at least once a year. For females, the estimated sizes at 50% physiological and functional maturity were (mean ± SE) 56.46 ± 0.56 mm CL and 66.63 ± 1.07 mm CL. The estimated sizes at functional maturity were between 72 and 74 mm CL for males. The number of eggs per spawning event (brood size, BS) was related to CL by the equation Y BS = 2.4 × 10-3CL4.18 (r 2 = 0.902, n = 12). Female lobsters with CL ranging from 60 to 80 mm made the greatest contributions to egg production because of their high brood size and active reproductive activity. A minimum legal size should be established for the fishery to protect egg production potential of lobster population in the southeastern coastal waters off Taiwan.  相似文献   
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