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51.
[Correction Notice: An erratum for this article was reported in Vol 15(3) of Group Dynamics: Theory, Research, and Practice (see record 2011-14268-001). An error was introduced during the production process. On article page 8, column 1 line 6 through column 2 line 2, the statement “…the main effect of expected longevity was significant only in the same expertise condition…” is incorrect. The effect found was for expected difficulty, not expected longevity.] The ability to effectively coordinate with others is a vital component of group success. It is often useful to base this coordination on expectations derived from perceived expertise (transactive memory; Wegner, 1986). Yet, the value of coordination overall and specific coordination strategies vary by task. We argue that the benefit of applying a task-appropriate coordination strategy increases with the number of trials of the task performed (expected longevity), and that the most beneficial strategy varies by task difficulty. We, therefore, predict that coordination increases with expected longevity and that the form of coordination (increased or decreased duplication) depends on expected task difficulty. To test these predictions we manipulate expectations of longevity and difficulty among individuals expecting to work with a partner on a memory task. The predicted relationships are found for both learning and recall. The implications of these findings for the development of transactive memory are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
52.
Tenebrio molitor, Zophobas morio, Alphitobius diaperinus, Acheta domesticus and Blaptica dubia were evaluated for their potential as a future protein source. Crude protein content ranged from 19% to 22% (Dumas analysis). Essential amino acid levels in all insect species were comparable with soybean proteins, but lower than for casein. After aqueous extraction, next to a fat fraction, a supernatant, pellet, and residue were obtained, containing 17–23%, 33–39%, 31–47% of total protein, respectively. At 3% (w/v), supernatant fractions did not form stable foams and gels at pH 3, 5, 7, and 10, except for gelation for A. domesticus at pH 7. At 30% w/v, gels at pH 7 and pH 10 were formed, but not at pH 3 and pH 5. In conclusion, the insect species studied have potential to be used in foods due to: (1) absolute protein levels; (2) protein quality; (3) ability to form gels.  相似文献   
53.
The invasive green alga, Caulerpa taxifolia, that has spread rapidly after its introduction into the Mediterranean and the North American Pacific, reacts to wounding by transforming its major metabolite caulerpenyne (1). This wound-activated reaction involves the transformation of the bis-enol acetate moiety of 1, releasing reactive 1,4-dialdehydes. The ability to perform this transformation is found also in both the noninvasive Mediterranean C. prolifera and the invasive C. racemosa. Trapping experiments, as well as transformation of the model substrate geranyl acetate, suggest that all three investigated Caulerpa spp. rely on esterases that act upon wounding of the algae by subsequently removing the three acetate residues of caulerpenyne. The resulting reactive 1,4-dialdehyde oxytoxin 2 (9) can be identified by liquid chromatography–mass spectrometry and is unstable in the wounded tissue. Caulerpenyne transformation occurs rapidly, and severe tissue damage caused degradation of more than 50% of the stored caulerpenyne within 1 min in all three algae. Prevention of the enzymatic reaction before extraction, by shock freezing the tissue with liquid nitrogen, was used for the determination of the caulerpenyne content in intact algae. It gives about twofold higher values compared to an established methanol extraction protocol. The speed and mechanism of the wound-activated transformation, as well as the caulerpenyne content in intact tissue of invasive and noninvasive Caulerpa spp., are comparable. Thus, this enzymatic , transformation, despite being fast and efficient, is likely not the key for the success of the investigated invasive species.  相似文献   
54.
Streaming media from the Internet is a successful application for end-users. With the upcoming success of mobile devices and home networking environments, cooperation among users will become more important in the future. To achieve such cooperation, explicit middleware standards have been defined. On the other hand, Internet conferencing applications do not handle collaborative streaming sessions with individual control for each user. We propose a new concept for cooperation exemplary for collaborative media streaming using IETF multimedia session control protocols together with a proxy architecture. This concept enables both synchronization among clients and flexible control to individual users.  相似文献   
55.
Leistungen der Pilgerstraßen, Stoßbänke und Kontistraßen bei der Herstellung nahtloser Rohre. Ermittlung wesentlicher Einflußgrößen auf diese Leistungen.  相似文献   
56.
Aufgabe des Unterprogrammes PHYWIZ. Ermittlung physikalischer Funktionen zur Erfüllung der Funktionen der festgelegten logischen Funktionskette. Variante physikalische Funktionen und Mehrfachzuordnungen. Programmstruktur zur Berechnung physikalischer Wirkzusammenhänge. Behandlung der unmittelbar schnittstellenabhängigen Zusammenhänge. Vorgehen bei Überschreitung der Schnittstellenbedingungen. Bearbeitung der physikalischen Wirkzusammenhänge, die keinen Einfluß auf die Schnittstellenbedingungen haben können. Bewertung varianter Funktionsketten und endgültige Festlegung auf eine physikalische Funktionskette.  相似文献   
57.
Beschreibung instationärer, mehrdimensionaler Wärmetransportvorgänge. Das Digitalrechenprogramm “WINST” zur Berechnung der Temperaturbewegungen in Rollen und Walzen, die mit Stahlsträngen oder Walzgut in Berührung stehen. Bestimmung der Unterschiede zwischen der gröβten und kleinsten Temperatur von Punkten der Oberfläche sowie solchen innerhalb einer Rolle oder Walze während einzelner Umdrehungen. Ermittlung der gröβten, während der Abläufe der Gieβ- oder Walzvorgänge erreichten Oberflächentemperaturen. Vergleich der Rechenergebnisse mit Meβwerten.  相似文献   
58.
Nestle N  Baumann T  Niessner R 《Water research》2003,37(14):3361-3366
In recent years, a rising number of different table waters supersaturated with oxygen have hit the market with claims of both positive health effects and an increase in athletic performance. In addition to research on the correctness of these claims and their possible physiological reasons, the appearance of oxygen supersaturation as a marketing promise also creates a need for appropriate analytical techniques allowing a rapid and reliable determination of oxygen contents in such waters. Here, we present NMR relaxometry as a possible analytical tool for such studies. NMR relaxation in oxygen supersaturated water is not only of interest in the context of monitoring the oxygen content in such drinking water products, but also might offer some interesting possibilities in medical and environmental science MRI applications. As a contact-less measuring method, NMR relaxometry avoids disturbance of the measurement due to outgassing. The method was applied in the concentration range from 10 mg l(-1) to over 100 mg l(-1) dissolved oxygen. In addition to freshly sampled drinking waters, also oxygen losses during storage of the water in open drinking vials was studied.  相似文献   
59.
This paper analyses how context- and time-dependent factors determine the impact of R&D subsidies on firm behaviour with respect to private R&D expenditures. Based on German R&D survey data, we combine propensity score matching with a difference-in-difference estimator in order to measure the causal influence of public direct R&D project funding on firm behaviour. Our results indicate that (i) repeated participation in R&D projects on average leads to a higher increase in R&D expenditures than once-off funding; (ii) the aggregate effect of R&D funding on R&D expenditures of business firms is somewhat higher for business–business collaboration projects than for science–business collaboration projects; (iii) R&D expenditures of business firms that cooperate with science show a higher share of external R&D spending. Results of one particular cluster programme indicate that at least the short-term development of R&D does not so much depend on which programme direct R&D project funding is applied to.  相似文献   
60.
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