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51.
It is commonly argued that we are witnessing a shift from global production networks, driven by the search for markets and lower cost production sites, to global innovation networks (GINs), driven by the search for knowledge. This paper explores how sources of behavioural differentiation derived from the literature on industrial knowledge bases and technological regimes condition the degree of involvement in international innovation collaboration. We find this to be significantly influenced by the nature of knowledge and the cumulativeness of knowledge development, the active use of measures to protect intellectual property, the inherent need to innovate and the opportunity to generate sales from this activity. The likelihood that the firm establishes and maintains a truly global network configuration is influenced accordingly.  相似文献   
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Abstract

In research on motor control, the detrimental effect of an internal focus of attention on movement execution of well-learned motor skills is a frequently replicated finding. This experimental study was designed to determine whether this effect is observed with physiological variables during endurance exercise. We examined whether the focus of attention can influence running economy (oxygen consumption at a set running speed). Trained runners had to focus their attention on three different aspects while running on a treadmill. For three consecutive 10-min periods, runners concentrated on the running movement, on their breathing, and on their surroundings. Results showed an increased running economy in the external focus condition. In line with research on motor control, endurance sport also shows that an external focus of attention is better than an internal focus in terms of the physiological performance measure of oxygen consumption.  相似文献   
54.
Dammann C  Nöding B  Köster S 《Biomicrofluidics》2012,6(2):22009-2200910
The structure and function of biological systems, for example, cells and proteins, depend strongly on their chemical environment. To investigate such dependence, we design a polydimethylsiloxane-based microfluidic device to encapsulate biological systems in picoliter-sized drops. The content of each individual drop is tuned in a defined manner. As a key feature of our method, the individual chemical composition is determined and related to the drop content. In our case, the drop content is imaged using microscopy methods, while the drops are immobilized to allow for long-time studies. As an application of our device, we study the influence of divalent ions on vimentin intermediate filament networks in a quantitative way by tuning the magnesium concentration from drop to drop. This way we are able to directly image the effect of magnesium on the fluorescently tagged protein in a few hundreds of drops. Our study shows that with increasing magnesium concentration in the drops, the compaction of the networks becomes more pronounced. The degree of compaction is characterized by different morphologies; freely fluctuating networks are observed at comparatively low magnesium concentrations of 5–10 mM, while with increasing magnesium concentration reaching 16 mM they develop into fully aggregated networks. Our approach demonstrates how a systematic study of interactions in biological systems can benefit from the exceptional controllability of microfluidic methods.  相似文献   
55.
Dinghy sailors lean their upper body over the windward side of the boat (‘hiking’) to keep the boat’s balance and maximise its speed. Sustaining the hiking position is essential for competitive performance and this study examined sport-specific differences of muscles relevant for hiking in elite sailors. Knee extensor muscle strength as well as trunk muscle strength, muscle endurance and muscle thickness were assessed in elite dinghy sailors (n = 15) and compared to matched, non-sailing controls (n = 15). Isometric extensor strength was significantly higher in sailors at 60° (+14%) but not at 20° knee flexion. Sailors showed significantly higher trunk flexor (but not extensor) strength under isometric (+18%) and eccentric (+11%) conditions, which was associated to greater muscle thickness (rectus abdominis +40%; external oblique +26%) and higher endurance for ventral (+66%) and lateral (+61%) muscle chains compared to non-sailors. Greater muscles thickness and the particular biomechanical requirements to maintain the hiking position may drive the increases in isometric and eccentric muscle strength as well as ventral and lateral trunk endurance. The current findings identified sport-specific muscle function differences and provide performance benchmarks for muscle strength and endurance in elite sailors.  相似文献   
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§ 85 UG erm?glicht die Ersetzung einer im Curriculum vorgeschriebenen wissenschaftlichen oder künstlerischen Arbeit durch eine sonstwo an einer anerkannten inl?ndischen oder ausl?ndischen postsekund?ren Bildungseinrichtung positiv beurteilte Arbeit im Wege der Anerkennung. Ma?gebliches Kriterium hiefür ist die Gleichwertigkeit zwischen "ausw?rtiger" und "heimischer" Arbeit; die Anerkennung kann auch studienrichtungsübergreifend erfolgen. In dieser Weise "suppliert" werden k?nnen Diplom- oder Masterarbeiten sowie künstlerische Diplom- oder Masterarbeiten, nicht jedoch Bachelorarbeiten und Dissertationen. W?hrend dies für Bachelorarbeiten sachlich gerechtfertigt werden kann, erweist sich der Ausschluss von Dissertationen aus dem System des § 85 UG als gleichheitswidrig.  相似文献   
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采用电子楔式制动器(Electronic Wedge Brake,EWB),现在可以设计12V线控刹车了!EWB是去年法兰克福车展上电子和机械电子产品开发商Siemens VDO推出的.  相似文献   
59.
Whereas numerous studies have confirmed the objectivity and reliability of the Allgemeine Sportmotorische Test für Kinder” (AST, a general motor fitness and coordination test for children), examinations of its construct validity reveal that: (1) the few available findings fail to confirm the theoretically predicted distinction between the latent variables of condition and coordination, and (2) no studies so far have examined its item homogeneity, even though the test recommends computing a sum score to provide a general estimate of motor fitness. Confirmatory factor analyses show that the two latent variables condition and coordination cannot be extracted from the AST. Models with different latent variables also cannot be confirmed, too. Analyses based on IRT models, in contrast, reveal that one can distinguish between two qualitative classes of persons who are associated with either better running performance combined with lower throwing performance or better throwing performance combined with lower running performance. Nonetheless, it should be noted that class membership does not remain constant over time. In sum, results based on classical and probabilistic test theory negate the ability assumption underlying the AST. For practical assessments of a skill-specific performance, this means that it only seems justifiable to use a sum score for the locomotion items and a sum score for the object manipulation items.  相似文献   
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This study investigates the structuring and sequencing of a special type of verbal-pictorial learning material, namely “explanative illustrations” (Mayer, 1993). In such illustrations verbal and pictorial parts form an integrated whole with text embedded in the pictures and vice versa. Due to their complexity such instructing illustrations impose high demands on information processing. From the viewpoint of instruction one may ask how the reception of such explanative illustrations may be supported by an appropriate structure and sequence of the content. In two empirical investigations three types of content structures and sequences were compared to each other: (1) a top-down sequence (based on assumptions of the “Elaboration Theory”, Reigeluth, 1987b) from the whole to details which shows how details are embedded within the larger context), (2) a bottom-up sequence from details to the whole, (3) the presentation as a whole (as in print).  相似文献   
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