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91.
Kammrath Lara K.; Mendoza-Denton Rodolfo; Mischel Walter 《Canadian Metallurgical Quarterly》2005,88(4):605
Three studies investigated conditions in which perceivers view dispositions and situations as interactive, rather than independent, causal forces when making judgments about another's personality. Study 1 showed that perceivers associated 5 common trait terms (e.g., friendly and shy) with characteristic if...then... (if situation a, then the person does x, but if situation b, then the person does y) personality signatures. Study 2 demonstrated that perceivers used information about a target's stable if...then... signature to infer the target's motives and traits; dispositional judgments were mediated by inferences about the target's motivations. Study 3 tested whether perceivers draw on if...then... signatures when making judgments about Big Five trait dimensions. Together, the findings indicate that perceivers take account of person-situation interactions (reflected in if...then... signatures) in everyday explanations of social behavior and personality dispositions. Boundary conditions are also discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
A Radial Basis Boltzmann Machine (RBBM) is a specialized Boltzmann Machine architecture that combines feed-forward mapping with probability estimation in the input space, and for which very efficient learning rules exist. The hidden representation of the network displays symmetry breaking as a function of the noise in the dynamics. Thus, generalization can be studied as a function of the noise in the neuron dynamics instead of as a function of the number of hidden units. We show that the RBBM can be seen as an elegant alternative of k-nearest neighbor, leading to comparable performance without the need to store all data. We show that the RBBM has good classification performance compared to the MLP. The main advantage of the RBBM is that simultaneously with the input-output mapping, a model of the input space is obtained which can be used for learning with missing values. We derive learning rules for the case of incomplete data, and show that they perform better on incomplete data than the traditional learning rules on a 'repaired' data set. 相似文献
93.
V Heinemann D Bosse U Jehn B K?hny K Wachholz A Debus P Scholz HJ Kolb W Wilmanns 《Canadian Metallurgical Quarterly》1997,41(6):1275-1280
The liposomal formulation of amphotericin B (AmBisome) greatly reduces the acute and chronic side effects of the parent drug. The present study describes the pharmacokinetic characteristics of AmBisome applied to 10 patients at a dose of 2.8 to 3.0 mg/kg of body weight and compares them to the pharmacokinetics observed in 6 patients treated with amphotericin B deoxycholate at the standard dose of 1.0 mg/kg. Interpatient variabilities of amphotericin B peak concentrations (Cmax) and areas under concentration-time curves (AUC) were 8- to 10-fold greater for patients treated with AmBisome than for patients treated with amphotericin B deoxycholate. At the threefold greater dose of AmBisome, median Cmaxs were 8.4-fold higher (14.4 versus 1.7 microg/ml) and median AUCs exceeded those observed with amphotericin B deoxycholate by 9-fold. This was in part explained by a 5.7-fold lower volume of distribution (0.42 liters/kg) in AmBisome-treated patients. The elimination of amphotericin B from serum was biphasic for both formulations. However, the apparent half-life of elimination was twofold shorter for AmBisome (P = 0.03). Neither hemodialysis nor hemofiltration had a significant impact on AmBisome pharmacokinetics as analyzed in one patient. In conclusion, the liposomal formulation of amphotericin B significantly (P = 0.001) reduces the volume of drug distribution, thereby allowing for greater drug concentrations in serum. The low toxicity of AmBisome therefore cannot readily be explained by its serum pharmacokinetics. 相似文献
94.
S Vasil'ev KD Irrgang T Schr?tter A Bergmann HJ Eichler G Renger 《Canadian Metallurgical Quarterly》1997,36(24):7503-7512
The protein composition, steady state and time-resolved fluorescence emission spectra were studied in solubilized and aggregated LHCII complexes, that were prepared according to two different isolation protocols: (1) by fractionation of cation-depleted thylakoid membranes using the non-ionic detergent Triton X-100 according to the procedure of Burke et al. [(1978) Arch. Biochem. Biophys. 187, 252-263] or (2) by solubilization with N-beta-dodecyl maltoside (beta-DM) of photosystem II (PSII) membrane fragments in the presence of cations [Irrgang et al. (1988) Eur. J. Biochem. 178, 207-217]. Based on the analysis of the decay-associated emission spectra measured at 10 and 80 K five long-wavelength chlorophyll species were identified in aggregated LHCII complexes. These five forms are characterized by emission maxima at 681.5, 683, 687, 695, or 702 nm. All of these forms were found in both types of LHCII preparations but the relative amounts and temperature dependency of these species were markedly different in the aggregated LHCII complexes isolated by the two procedures. It was found that these differences cannot be simply explained by effects due to using a less mild detergent as beta-DM or by an ionic influence of Ca2+. Biochemical analysis of the protein composition showed that beta-DM type LHCII consists of all the chlorophyll (Chl)binding proteins belonging to the antenna system of PSII except the CP29 type II gene product (CP29). In contrast, the Triton X-100-solubilized LHCII is highly depleted in CP26 (CP 29 type I gene product) and is contaminated by a variety of unidentified polypeptides. It is proposed that the aggregates of LHCII prepared using Triton X-100 acquire specific spectral and kinetic features due to interaction between the bulk of LHCII subunits and minor protein(s). 相似文献
95.
There have been extensive attempts in recent years to perform spatial equilibrium analysis of commodity markets, particularly that of energy. Most of these attempts have been based on linear programming transportation models, and more recently quadratic programming models. Unfortunately, neither of these modelling approaches can deal with the case of multi-commodity analysis with non-symmetric regression coefficients. In this paper, we overcome this problem by employing the linear complementarity programming model. In addition, we show how the model can be applied to coal and gas energy flows within a single region. Future potential applications of the model are also implied. 相似文献
96.
Evaluation of the retroperitoneum is important to assess the extent of retroperitoneal malignancies and because the retroperitoneum is a route of nodal spread for other malignancies. Positron emission tomography (PET) with 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG) allows detection of small malignant nodes not identified or not meeting size criteria for malignancy with computed tomography (CT) and tumor recurrences in surgical beds that are otherwise difficult to assess. However, evaluation of retroperitoneal malignancies or adenopathy with FDG PET can be complicated by urinary and colonic activity or anatomic variants. Urinary artifacts are avoided with intravenous hydration, administration of furosemide, and catheterization and retrograde filling of the bladder with saline solution. Colonic artifacts are avoided by cleansing the bowel with an isosmotic solution. FDG PET is useful in assessing the retroperitoneum for adenopathy in malignancies such as testicular cancer; lymphoma; and rectal ovarian, or cervical cancer that spread along retroperitoneal lymphatics. FDG PET is especially useful for detection of malignant nodes that do not meet size criteria at CT or when lack of retroperitoneal fat makes it difficult to identify retroperitoneal nodes with CT. FDG PET has an important role in evaluation of postoperative beds, where CT has limited useful because of altered anatomy, surgical clip artifacts, and scar issue. 相似文献
97.
M Heller J Blanke F Draijer J Brossmann HJ Egbers D Havemann 《Canadian Metallurgical Quarterly》1998,38(8):702-709
PURPOSE: Analysis of the trauma patient of fractures of the pelvic ring and classification according to AO/Tile. METHODS: 125 unselected patients (43 females, 82 males) were evaluated retrospectively by conventional x-ray, and CT examinations included follow-studies. RESULTS: Type-A fractures were seen in 36 (29%), Type-B fractures in 58 (46%), and Type-C fractures in 31 (25%) cases. Type-B and Type-C fractures mainly occurred in patients with traffic accidents and falls from great height. Type-A fractures were seen most often in patients with accidents at home or at work. However, in patients with complex fractures a classification concerning Type-B or Type-C fractures was difficult. SUMMARY: Based on CT criterias, in most patients a statement concerning the applied forces, the stability of the pelvic rim and the fracture type can be made. 相似文献
98.
HJ Ward 《Canadian Metallurgical Quarterly》1998,352(9129):670-671
99.
Increased use of titanium alloys as biomaterials is occurring due to their lower modulus, superior biocompatibility and enhanced corrosion resistance when compared to more conventional stainless steels and cobalt-based alloys. These attractive properties were a driving force for the early introduction of alpha (cpTi) and alpha + beta (Ti-6A1-4V) alloys as well as for the more recent development of new Ti-alloy compositions and orthopaedic metastable beta titanium alloys. The later possess enhanced biocompatibility, reduced elastic modulus, and superior strain-controlled and notch fatigue resistance. However, the poor shear strength and wear resistance of titanium alloys have nevertheless limited their biomedical use. Although the wear resistance of beta-Ti alloys has shown some improvement when compared to alpha + beta alloys, the ultimate utility of orthopaedic titanium alloys as wear components will require a more complete fundamental understanding of the wear mechanisms involved. This review examines current information on the physical and mechanical characteristics of titanium alloys used in artifical joint replacement prostheses, with a special focus on those issues associated with the long-term prosthetic requirements, e.g., fatigue and wear. 相似文献
100.