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61.
This study aims at the quantification of possible future nutrient loads into Lake Peipsi/Chudskoe under different economic development scenarios. This drainage basin is on the borders of Russia, Estonia and Latvia. The sudden disintegration of the Soviet Union in 1991 caused a collapse of agricultural economy, and consequently, a substantial decrease of diffuse and point-source nutrient emissions. For the future, uncertainties about economic development and the priorities that will be set for this region make it difficult to assess the consequences for river water quality and nutrient loads into the lake. We applied five integrated scenarios of future development of this transboundary region for the next twelve to fifteen years. Each scenario consists of a qualitative story line, which was translated into quantitative changes in the input variables for a geographical information system based nutrient transport model. This model calculates nutrient emissions, as well as transport and retention and the resulting nutrient loads into the lake. The model results show that the effects of the different development scenarios on nutrient loads are relatively limited over a time span of about 15 years. In general, a further reduction of nutrient loads is expected, except for a fast economic development scenario.  相似文献   
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Palladium complexes have been shown to strongly inhibit cellobiohydrolase I (CBH I) and endoglucanase II (EG II), two cellulases produced by Trichoderma reesei. Also inhibited were total cellulase (Avicelase) and beta-glucosidase (cellobiase) activities. The catalytic domain of CBH II, the second most abundant component of this cellulase, appeared less susceptible to inhibition by palladium. The inhibition was irreversible and could be prevented if histidine, cysteine or cystine was added to the enzyme reaction mixture simultaneously with the inhibitor. The binding of CBH I to microcrystalline cellulose (Avicel) was unaffected by palladium.  相似文献   
64.
In this work, a new method for inserting a surface as an internal boundary into an existing unstructured tetrahedral mesh is developed. The surface is discretized by initially placing vertices on its bounding curves, defining a length scale at every location on each boundary curve based on the local underlying mesh, and equidistributing length scale along these curves between vertices. The surface is then sampled based on this boundary discretization, resulting in a surface mesh spaced in a way that is consistent with the initial mesh. The new points are then inserted into the mesh, and local refinement is performed, resulting in a final mesh containing a representation of the surface while preserving mesh quality. The advantage of this algorithm over generating a new mesh from scratch is in allowing for the majority of existing simulation data to be preserved and not have to be interpolated onto the new mesh. This algorithm is demonstrated in two and three dimensions on problems with and without intersections with existing internal boundaries. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
65.
Many systems could be high-resistance grounded?with the traceable signal to locate the first ground fault?to result in a safe, economical, reliable, and uncomplicated method of grounding of 480-. 2400-, and 4160-V delta or wye 3-wire systems?with these benefits  相似文献   
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The authors have investigated the use of a time-domain optimal filtering method to simultaneously minimize both the baseline variation and high-frequency noise in near-infrared (NIR) spectrophotometric absorption data of glucose dissolved in a simple aqueous (deionized water) matrix. By coupling a third-order (6-pole) digital Butterworth bandpass filter with partial least-squares (PLS) regression modeling, glucose concentrations were determined for a set of test data with a standard error of prediction (SEP) of 10.53 mg/dl (mean percent error: 4.24%) using 7 PLS factors. Compared to the unfiltered test data for 6 PLS factors and a SEP=17.00 (mean percent error: 7.38%) this results shows more than a 38% decrease in the error. The glucose concentrations ranged from 51 mg/dl to 493 mg/dl, and the NIR spectral region between 2088 nm and 2354 nm (4789 cm-1 and 4248 cm-1) was used to develop the optimal PLS model. The optimal PLS model was determined from a sequence of 3-dimensional performance response maps for different numbers of PLS factors (2-10). A total of 99 NIR spectra were generated for glucose dissolved in deionized water using a NIRsystems 5000 dispersive spectrophotometer. Nine of these spectra were generated for only water, which were averaged and subtracted from the remaining 90 spectra to generate the training and test data sets, thereby, removing the intrinsic high background absorption due to the water. The training set consisted of 57 spectra and associated glucose concentration target values, and the test set was comprised of the remaining 33 spectra and target values. Performance results were compared for 3 different digital Butterworth bandpass filters (4-poles, 6-poles, and 8-poles), and a digital Gaussian filter design approach (i.e., Fourier filtering)  相似文献   
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We present an adaptive antenna algorithm for Gaussian minimum-shift keying (GMSK)-based cellular systems with beamformer weights that are iteratively computed using re-encoded data to suppress cochannel interference (CCI). Filtered training sequences are proposed in order to compensate for the effects of timing offsets that occur for asynchronous cochannel signals. Also, we extend the receiver to include a linear equalizer that mitigates intersymbol interference (ISI). Various multistage receivers incorporating the proposed beamformer and equalizer algorithms are presented. Their performance is evaluated using simulated and real time-division multiple-access (TDMA) data, demonstrating that the proposed beamforming algorithms suppress CCI and significantly improve the performance compared to a conventional GMSK receiver.
Richard P. GoochEmail:
  相似文献   
69.
A new unstructured mesh coarsening algorithm has been developed for use in conjunction with multilevel methods. The algorithm preserves geometrical and topological features of the domain, and retains a maximal independent set of interior vertices to produce good coarse mesh quality. In anisotropic meshes, vertex selection is designed to retain the structure of the anisotropic mesh while reducing cell aspect ratio. Vertices are removed incrementally by contracting edges to zero length. Each vertex is removed by contracting the edge that maximizes the minimum sine of the dihedral angles of cells affected by the edge contraction. Rarely, a vertex slated for removal from the mesh cannot be removed; the success rate for vertex removal is typically 99.9% or more. For two‐dimensional meshes, both isotropic and anisotropic, the new approach is an unqualified success, removing all rejected vertices and producing output meshes of high quality; mesh quality degrades only when most vertices lie on the boundary. Three‐dimensional isotropic meshes are also coarsened successfully, provided that there is no difficulty distinguishing corners in the geometry from coarsely‐resolved curved surfaces; sophisticated discrete computational geometry techniques appear necessary to make that distinction. Three‐dimensional anisotropic cases are still problematic because of tight constraints on legal mesh connectivity. More work is required to either improve edge contraction choices or to develop an alternative strategy for mesh coarsening for three‐dimensional anisotropic meshes. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
70.
Sinonasal infection with fungi of the order Mucorales--termed mucormycosis or zygomycosis--is sometimes seen in immunosuppressed patients, including those with diabetic ketoacidosis and malignancy. We describe a case of invasive sinonasal infection with Scopulariopsis candida (not among the Mucorales organisms) in a 12-year-old girl who was being treated for non-Hodgkin's lymphoma. Only a few cases of invasive infection with Scopulariopsis species have been reported previously; five of six of these cases were associated with persistent or fatal disease. Our patient survived without undergoing radical surgical debridement and was treated with granulocyte colony-stimulating factor, amphotericin B, and itraconazole; chemotherapy was stopped. In vitro susceptibility testing of our patient's Scopulariopsis isolate showed that it was resistant to amphotericin B and that it was relatively susceptible to itraconazole and miconazole. The case described herein demonstrates the expanding spectrum of fungal organisms that may cause invasive sinonasal infection in immunocompromised hosts and the need for reliable antifungal susceptibility testing.  相似文献   
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