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1.
The biotransformation of oxazepam by Bifidobacterium bifidum was studied. The major metabolite was purified by chromatographic methods and found to be desmethyldiazepam using NMR, IR and other physicochemical data.  相似文献   
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During the process of writing a comprehensive dictionary ofFinnish dialects, a large set of maps describing the regionaldistribution of the dialect words have been compiled in electronicform. In this article, we set out to analyse this corpus ofdata in order to gain new insight on the variation of Finnishdialects. We use a wide range of multivariate data analysismethods, including principal components analysis, independentcomponents analysis, clustering, and multidimensional scaling.We explain how to preprocess the data to overcome the problemof uneven sampling caused by the way the data has been collected.We discuss the results obtained by these methods and comparethem to the traditional view of Finnish dialect groups.  相似文献   
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Laboratory-scale ageing and poisoning procedures were performed on selected diesel catalysts. The results showed that phosphorus poisoning together with high temperature ageing has a strong effect on the catalytic activity and microstructure of platinum containing catalysts. Phosphorus poisoning contaminated the catalysts resulting in phosphate formation, e.g. CePO4 and AlPO4. Poisoning and air ageing increased platinum particle-size and washcoat grain-size.  相似文献   
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The effect of metal-composite debonding on low-velocity impact response, i.e. on contact force–central deflection response, deformation profiles and strains on the free surfaces was studied. We focused on type 2/1 fibre metal laminate specimens made of stainless steel and carbon fibre epoxy layers, and tested them with drop-weight impact and quasi-static indentation loadings. Local strains were measured with strain gauges and full-field strains with a 3-D digital image correlation method. In addition, finite element simulations were performed and the effects of debonding were studied by exploiting cohesive elements. Our results showed that debonding, either the initial debonding or that formed during the loading, lowers the slope of the contact force–central deflection curve during the force increase. The debonding formation during the rebound phase was shown to amplify the rebound of the impact side, i.e. to lower the ultimate post-impact deflection. The free surface strains were studied on the laminate’s lower surface at the area outside the debond damage. In terms of in-plane strains, debonding formation during impact and indentation, as well as the initial debonding, lowered the peripheral strain and resulted in a positive change in the radial strain.  相似文献   
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Proposes 10 models for predicting a student's final grade placement in a computer-assisted instruction curriculum from the time the student spends taking lessons. Using data from approximately 2,000 elementary students, the models are tested both for ability to predict final grade placement and for ability to describe all points observed throughout the year. Two of the simplest models, using only the most recent point and parameters estimated for the whole group, are best at prediction. The power function model with all parameters estimated individually for each student, while relatively poor at prediction, is best for describing all observed points. Several methods for predicting the amount of time a student will spend taking lessons during a year are also tested. (4 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Deep brain stimulation (DBS) is effective in reducing motor symptoms in Parkinson's disease (PD). However, objective methods for quantifying its efficacy are lacking. We present a principal component (PC)-based tracking method for quantifying the effects of DBS in PD by using electromyography (EMG) and acceleration measurements. Ten parameters capturing PD characteristic signal features were initially extracted from isometric EMG and acceleration recordings. Using a PC approach, the original parameters were transformed into a smaller number of PCs. Finally, the effects of DBS were quantified by examining the PCs in a low-dimensional feature space. The EMG and acceleration data from 13 PD patients with DBS ON and OFF, and 13 healthy age-matched controls were used for analysis. Clinical evaluation of patients showed that their motor symptoms were effectively reduced with DBS. The analysis results showed that the signal characteristics of 12 patients were more similar to those of the healthy controls with DBS ON than with DBS OFF. These observations indicate that the PC-based tracking method can be used to objectively quantify the effects of DBS on the neuromuscular function of PD patients. Further studies are suggested to estimate the clinical sensitivity of the method to different types of PD.  相似文献   
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Kröger  V.  Kanerva  T.  Lassi  U.  Rahkamaa-Tolonen  K.  Lepistö  T.  Keiski  R. L. 《Topics in Catalysis》2007,42(1-4):433-436
Powdered ZSM-5 and Pt/ZSM-5 catalysts were studied as fresh and after two treatments: hydrothermal ageing and phosphorus poisoning in hydrothermal conditions. The results showed that the deactivating effect of phosphorus was stronger than the effect of the hydrothermal treatment alone. Phosphorus had accumulated in the samples during the ageing. The decrease in specific surface area and increase in Pt particle size indicated the possible reasons for deactivation.  相似文献   
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