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31.
In 4 experiments, we investigated the effects of object affordance in reach-to-grasp actions. Participants indicated whether a depicted small or large object was natural or manmade by means of different object-grasping responses (i.e., with a power or a precision grip). We observed that the size of the depicted object affected the grasping kinematics (grip aperture) and the reach-onset times of compatible and incompatible actions. Additional experiments showed that the effect of perceived object size on motor response was modulated by contextual action information and the observation of others’ actions with the object. Thus, beyond the observation of object affordance effects in natural grasping actions, this study suggests that the coupling between object perception and action is not static and obligatory. Behavioral effects of action-relevant object features seem rather to depend on contextual action information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
32.
Definition of the problem The central focus of Empirical Ethics is the study of the social and cultural aspects inherent in medical practice. Arguments This approach distinguishes between the scientific-cognitive aspects and the cultural-normative aspects of medicine, which would conventionally be investigated separately by the social sciences. When however medicine is conceived of as social practice, the sharp distinction between scientific medicine, culturally normative aspects and ethical reflection becomes less distinct. Conclusion We suggest combining ethical reflection and empirical research in multiple stages. In this case, social scientific analyses would provide an initial framework for understanding medical practices and a foundation for further ethical investigations, which would then allow for a sociological critique.  相似文献   
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An approach for the identification of unknown selenium-containing biomolecules was developed, enabling the identification of selenodiglutathione (GS-Se-SG) and the mixed selenotrisulfide of glutathione and cysteinylglycine (GS-Se-SCG) in aqueous yeast extracts. The method consists of two-dimensional liquid chromatography, inductively coupled plasma mass spectrometry (ICPMS) and nanoelectrospray tandem mass spectrometry. Analytes were separated by size-exclusion chromatography followed by preconcentration and separation on a porous graphitic carbon HPLC column. The HPLC effluent was monitored for selenium by ICPMS, and two selenium-containing fractions were isolated and analyzed by nanoelectrospray MS. The nanoelectrospray technique has a low sample consumption of approximately 80 nL/min, enabling a preconcentration of the sample to a few microliters. Mass spectra of the two fractions showed the characteristic Se isotopic pattern centered at m/z 693.1 and 564.0 for the [M + H]+ 80Se ions. MS/MS spectra of adjacent parent ions confirmed the presence of Se. The two selenium species were identified as GS-Se-SG and GS-Se-SCG by collision induced dissociation (CID). The accurately measured masses of the most abundant 691 and 693 u parent ions are in good agreement (differences = 3 ppm) with the theoretical masses. To our knowledge, this is the first identification of GS-Se-SG and GS-Se-SCG in biological matrixes by MS/MS.  相似文献   
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A compact airborne spectrographic imager (CASI) mounted on top of an attitude stabilizing platform inside a Cessna 207T was used to monitor changes in and around a lake near Berlin for 4 months in 1993-1994. The radiance was recorded at three different altitudes in the wavelength range 0.4-0.9 mu m. The observed radiances were found to be different from 1 month to another due to the variability of phytoplankton and suspended solids in the lake. The observed radiance was similar when measured at three different altitudes during the same month, whereas the effect of altitude was seen when comparing the radiances from month to month. The radiances in the month of May 1994 have been found to be anomalous when comparing the radiances measured at the altitudes 1500 and 2000 m in the months of July and September 1993 and February 1994. This anomaly was found to be associated with aerosol concentration around an altitude of 1500-2000 m in the atmosphere as compared with LOWTRAN modelling.  相似文献   
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To investigate the functional connection between numerical cognition and action planning, the authors required participants to perform different grasping responses depending on the parity status of Arabic digits. The results show that precision grip actions were initiated faster in response to small numbers, whereas power grips were initiated faster in response to large numbers. Moreover, analyses of the grasping kinematics reveal an enlarged maximum grip aperture in the presence of large numbers. Reaction time effects remained present when controlling for the number of fingers used while grasping but disappeared when participants pointed to the object. The data indicate a priming of size-related motor features by numerals and support the idea that representations of numbers and actions share common cognitive codes within a generalized magnitude system. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
38.
A procedure for pickle room control for porcelain enameling plants is outlined and “make up” for four cleaning solutions are given in detail.  相似文献   
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In this paper extensions to the numerical solution method of deterministic and stochastic Petri nets (DSPNs) are introduced in order to cope with deterministic transitions with marking-dependent firing delays. The basic idea lies in scaling each row of the generator matrix of the Markov chain subordinated to a deterministic transition with marking-dependent firing delay by the delay value corresponding to this marking. Computational formulas of this solution method are implemented in the software package DSPNexpress which completely automates the solution process of DSPNs. The extended modeling power of DSPNs is illustrated by a single-server queuing system with Poisson arrivals, degradable deterministic service requirements, and finite capacity. Christoph Lindemann was supported by the Federal Ministry for Research and Technology of Germany (BMFT) and by the German Research Council (DFG) under grants ITR9003 and Ho 1257/2-1, respectively. Reinhard German was supported by Siemens Corporate Research and Development and by a doctoral fellowship from the German Research Council (DFG) under grant Ho 1257/1-2.  相似文献   
40.
 在CAD系统与计算程序协同工作中发生的数据交换,应理想地沿两个方向进行,以支持产品开发过程,
这通常称为“双向数据交换”.然而,如何对此概念准确理解,学术界在表述上都不尽相同.原本意义上的单向数据
交换,可以按序反向地进行,而被说成是“双向”的.这样,在一种事实上每时每刻都沿双向进行的数据交换之外,还
存在一个相同的提法. 然而,这两种方案有根本区别的. 由此,对概念进行区分,并指出其差别.  相似文献   
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