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1.
Jan Buijs 《Creativity & Innovation Management》2007,16(2):203-210
Innovating is a multi‐faceted process. In this paper, four different, yet intertwined aspects of this process are distinguished. The first aspect concerns the content of the innovation; a new product, a new technology or a new market. The second aspect concerns the group dynamics of the innovation team. The third aspect concerns seeing the innovation process as a creative process. And the fourth aspect has to do with leadership. Since these four aspects are simultaneously working together during the innovation process, the leaders of this process are working in a very difficult situation, as all four aspects need to be dealt with in different ways. Nearly all of them are, in one way or another, in conflict with one another. They may conflict in real actions, in time horizons (past, present or future) or in effect (positive reactions during market introduction do not garantee ultimate market success). This means that innovation leaders need to show a special kind of leadership. This leadership must be balanced, people‐focused and must include a high tolerance for ambiguity and paradoxes. They have to be nice and nasty at the same time. In short: innovation leaders should be some kind of controlled schizophrenics. 相似文献
2.
This paper discusses the results of a study of actinide surrogates in a nuclear borosilicate glass to understand the effect of processing conditions (temperature and oxidizing versus reducing conditions) on the solubility limits of these elements. The incorporation of cerium oxide, hafnium oxide, and neodymium oxide in this borosilicate glass was investigated. Cerium is a possible surrogate for tetravalent and trivalent actinides, hafnium for tetravalent actinides, and neodymium for trivalent actinides. The material homogeneity was studied by optical, scanning electron microscopy. Cerium LIII XANES spectroscopy showed that the Ce3+/Cetotal ratio increased from about 0.5 to 0.9 as the processing temperature increased from 1100 to 1400 °C. Cerium LIII XANES spectroscopy also confirmed that the increased Ce solubility in glasses melted under reducing conditions was due to complete reduction of all the cerium in the glass. The most significant results pointed out in the current study are that the solubility limits of the actinide surrogates increases with the processing temperature and that Ce3+ is shown to be more soluble than Ce4+ in this borosilicate glass. 相似文献
3.
J G De Nobel F M Klis A Ram H Van Unen J Priem T Munnik H Van Den Ende 《Yeast (Chichester, England)》1991,7(6):589-598
To study cell-cycle-related variations in wall permeability of Saccharomyces cerevisiae, two approaches were used. First, an asynchronous culture was fractionated by centrifugal elutriation into subpopulations containing cells of increasing size. The subpopulations represented different stages of the cell cycle as judged by light microscopy. Cell wall porosity increased when these subpopulations became enriched with budded cells. Secondly, synchronous cultures were obtained by releasing MATa cells from alpha-factor induced G1-arrest. These cultures grew synchronously for at least two generations. The cell wall porosity increased sharply in these cultures, shortly before buds became visible and was maximal during the initial stages of bud growth. It decreased in cells which had completed nuclear migration and before abscission of the bud had occurred. The porosity reached its lowest value during abscission and in unbudded cells. We examined the incorporation of mannoproteins into the wall during the cell cycle. SDS-extractable mannoproteins were incorporated continuously. However, the incorporation of glucanase-extractable mannoproteins, which are known to affect cell wall porosity, showed cyclic oscillations and reached its maximum after nuclear migration. This coincided with a rapid decrease in cell wall porosity, indicating that glucanase-extractable mannoproteins might contribute to this decrease. 相似文献
4.
E Danielsen R Bauer L Hemmingsen MJ Bjerrum T Butz W Tr?ger GW Canters T Den Blaauwen G Van Pouderoyen 《Canadian Metallurgical Quarterly》1995,233(2):554-560
The present work uses 111mCd-perturbed angular correlations of gamma-rays (PAC) to investigate the structure of the metal site of the His117Gly mutant of Pseudomonas aeruginosa azurin in aqueous solution and the effect on the structure upon addition of the following exogenous ligands: imidazole, 4-methyl imidazole, 1-methyl imidazole, 2-methyl imidazole and histidine. The nuclear quadrupole interaction of cadmium bound to the mutant without addition of exogenous ligands shows a strong pH dependence with three different nuclear quadrupole interactions consistent with two pKa values at about 7.2 and 8.6 at 2 degrees C. Addition of the imidazole derivatives resulted in a significant change in the PAC spectrum showing that they coordinate. This is in accordance with observations by EPR for the same mutant with copper at the metal site [den Blaauwen, T. & Canters, G. W. (1993) J. Am. Chem. Soc. 115, 1121-1129]. However, whereas EPR and ultraviolet/visual absorption show that the characteristics of the wild-type copper protein are regained by addition of the imidazole derivatives with the exception of the possible bidentates (histidine and histamine), the comparison of the PAC results to model calculations shows that the cadmium ion must be fourfold coordinated in most cases, probably binding an additional water or hydroxide ligand. A fourfold coordination is in contrast to cadmium-substituted wild-type azurin where PAC data inferred a threefold coordination by a Cys and two His residues [Danielsen, E. Bauer, R., Hemmingsen, L., Andersen. M., Bjerrum, M. J., Butz, T., Tr?ger, W., Canters, G. W., Hoitink, C. W. G., Karlsson, G., Hansson, O. & Messerschmidt, A. (1995) J. Biol. Chem. 270, 573-580] 相似文献
5.
The presented hardware controller controls the current in an active shield consisting of a number of compensation coils at well-chosen positions. In combination with a converter and the active shield, the controller reduces the fundamental component of the magnetic stray field of an induction heater by generating a magnetic counter field in a defined target area. The controller uses two input signals (from two magnetic field sensors) and generates amplitude and phase information for the converter. Based on this information, the latter produces the compensation current wave that is sent to the compensation coils to minimise the magnetic field. The frequency range of the controller is 1-100 kHz. Its dynamic behaviour is explained in theory and validated by experiments 相似文献
6.
In vitro triggering of somatic mutation in human naive B cells 总被引:1,自引:0,他引:1
D Razanajaona S Denépoux D Blanchard O de Bouteiller YJ Liu J Banchereau S Lebecque 《Canadian Metallurgical Quarterly》1997,159(7):3347-3353
During T cell-dependent immune response, germinal center B cells accumulate somatic mutations in their Ig V(D)J genes and give rise to affinity-selected B cells. We tested several culture conditions for triggering somatic mutation in human tonsillar naive slgD+CD23+ cells after cross-linking their membrane Igs. CD40 activation, in the presence of exogenous cytokines (IL-2, IL-4, and IL-10), induced proliferation and isotype switch without somatic mutation. In contrast, after coculture with anti-CD3-activated cloned T cells, somatic mutation accumulated in a fraction of naive B cells. Mutations included shared as well as independent events in clonally related sequences, allowing reconstitution of genealogic trees generated in vitro. Naive tonsillar B cells sorted for slgD expression can be induced to mutate their Ig V(H) gene upon coculture with activated T cells, thereby providing a model to study somatic hypermutation in vitro. 相似文献
7.
The most common chromosomal aberrations in myelodysplastic syndromes (MDS) are complete or partial loss of chromosomes 5 and 7, and trisomy 8. To identify genes important in the pathogenesis of this disease that could be associated with these gross chromosomal defects, we have employed the differential display PCR (DDPCR) procedure developed by Liang and Pardee. This method allows simultaneous comparison of several cDNA sources for the presence of differentially expressed genes. Polymorphonuclear cells (PMNs) from two MDS patients, containing a 5q deletion or a trisomy 8, and three healthy controls were used. Initial screening resulted in the identification of five and three partial cDNA sequences, respectively that were either differentially expressed in both patient samples or in individual patients, as compared with the controls. The authenticity of aberrant expression was verified by reanalyzing the same primer combinations on newly prepared cDNA. Differential expression of the three remaining fragments was subsequently checked on a larger panel of MDS patients, using amplicon-specific primer sets. These were obtained by cloning and sequencing of the fragments. For one partial cDNA (DC3), the original expression pattern, i.e., decreased expression in individual MDS patients, was confirmed. These results demonstrate the utility of the DDPCR procedure to isolate differentially expressed sequences in primary patient samples where the availability of cells is a limiting factor. 相似文献
8.
In our previous research, we found that crosslinking paper using poly(carboxylic acid)s with different molecular weight or using the combination of glutaraldehyde and poly(vinyl alcohol) (PVA) significantly improved the wet strength of the paper. In this research, we studied the mechanism of paper wet strength development using crosslinking systems with different molecular weight by measuring scanning electron microscopic (SEM) images, wet strength, folding endurance, wet thickness, water retention, and Z‐direction tensile strength of the treated paper. The paper crosslinked by a high‐molecular weight (MW) poly(carboxylic acid) shows more swelling by water than that crosslinked by a low‐MW polycarboxylic acid in the SEM micrographs even though both treated paper samples have similar wet strength. Thus, the data suggest that high‐MW poly(carboxylic acid)s promote the formation of interfiber crosslinking. Crosslinking paper by glutaraldehyde, a crosslinking agent of small molecular size, improves wet strength and reduces flexibility and swellability of paper because of the formation of intrafiber crosslinking. Combining glutaraldehyde with PVA as a coreactant increases wet strength and also retains flexibility and swellability of the treated paper because of the formation of interfiber crosslinking. The hypothesis that PVA reacts with glutaraldehyde to form a polymeric pentanedialated‐PVA crosslinking system and promotes the formation of interfiber crosslinking on the paper is supported by the data of wet strength, folding endurance, wet thickness, water retention, and Z‐direction tensile strength of the treated paper. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 277–284, 2006 相似文献
9.
Kikuo Maekawa Makoto Yamazaki Toshinobu Ogiso Takehiko Maruyama Hideki Ogura Wakako Kashino Hanae Koiso Masaya Yamaguchi Makiro Tanaka Yasuharu Den 《Language Resources and Evaluation》2014,48(2):345-371
The balanced corpus of contemporary written Japanese (BCCWJ) is Japan’s first 100 million words balanced corpus. It consists of three subcorpora (publication subcorpus, library subcorpus, and special-purpose subcorpus) and covers a wide range of text registers including books in general, magazines, newspapers, governmental white papers, best-selling books, an internet bulletin-board, a blog, school textbooks, minutes of the national diet, publicity newsletters of local governments, laws, and poetry verses. A random sampling technique is utilized whenever possible in order to maximize the representativeness of the corpus. The corpus is annotated in terms of dual POS analysis, document structure, and bibliographical information. The BCCWJ is currently accessible in three different ways including Chunagon a web-based interface to the dual POS analysis data. Lastly, results of some pilot evaluation of the corpus with respect to the textual diversity are reported. The analyses include POS distribution, word-class distribution, entropy of orthography, sentence length, and variation of the adjective predicate. High textual diversity is observed in all these analyses. 相似文献
10.
New and very strong criteria are presented for a priori prediction of the conditions for which the steady-state lumped parameter model of an nth order chemical reaction (n ≥ 0) in an adiabatic CSTR has either a unique or multiple solutions. The criteria show that the higher the order of the reaction the smaller is the region in the parameters space for which multiplicity can occur.New uniqueness and multiplicity criteria are developed also for an nth order reaction in a porous catalyst using a model, which accounts for intraparticle concentration gradients, while assuming a uniform intraparticle temperature different from the ambient one. The region in the parameters space for which steady state multiplicity can occur for this model is smaller than that for a corresponding lumped model, which ignores the intraparticle concentration gradients. 相似文献