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11.
The article presents an analysis of a large-scale survey with the aim of understanding differences in the open, interactive and distributed nature of external innovation relations amongst firms belonging to different industrial knowledge bases. The thesis is that the source of critical innovation relevant knowledge differs between industrial knowledge bases, making the character and the need of openness contingent on these specificities. Accordingly, we anticipate that we will observe systematic variations in how industries access and combine innovation-related external knowledge. In our analyses we attempt to address a gap in the literature by examining how industrial knowledge bases affect the recombination of knowledge by analysing the different extents, forms (formal and informal) and geography of inbound open innovation. The article illustrates that features and structures of inbound open innovation align, to a large extent, with the industries' knowledge bases and that there is a interplay between an industry's knowledge base, the internal organisation of innovation processes and the channels and geography of inbound open innovation. 相似文献
12.
Little is known about how people structure sets of visualizations to support sequential viewing. We contribute findings from several studies examining visualization sequencing and reception. In our first study, people made decisions between various possible structures as they ordered a set of related visualizations (consisting of either bar charts or thematic maps) into what they considered the clearest sequence for showing the data. We find that most people structure visualization sequences hierarchically: they create high level groupings based on shared data properties like time period, measure, level of aggregation, and spatial region, then order the views within these groupings. We also observe a tendency for certain types of similarities between views, like a common spatial region or aggregation level, to be seen as more appropriate categories for organizing views in a sequence than others, like a common time period or measure. In a second study, we find that viewers’ perceptions of the quality and intention of different sequences are largely consistent with the perceptions of the users who created them. The understanding of sequence preferences and perceptions that emerges from our studies has implications for the development of visualization authoring tools and sequence recommendations for guided analysis. 相似文献
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Eva Harlacher Julia Wollenhaupt Constance C. F. M. J. Baaten Heidi Noels 《International journal of molecular sciences》2022,23(1)
Patients with chronic kidney disease (CKD) are at a highly increased risk of cardiovascular complications, with increased vascular inflammation, accelerated atherogenesis and enhanced thrombotic risk. Considering the central role of the endothelium in protecting from atherogenesis and thrombosis, as well as its cardioprotective role in regulating vasorelaxation, this study aimed to systematically integrate literature on CKD-associated endothelial dysfunction, including the underlying molecular mechanisms, into a comprehensive overview. Therefore, we conducted a systematic review of literature describing uremic serum or uremic toxin-induced vascular dysfunction with a special focus on the endothelium. This revealed 39 studies analyzing the effects of uremic serum or the uremic toxins indoxyl sulfate, cyanate, modified LDL, the advanced glycation end products N-carboxymethyl-lysine and N-carboxyethyl-lysine, p-cresol and p-cresyl sulfate, phosphate, uric acid and asymmetric dimethylarginine. Most studies described an increase in inflammation, oxidative stress, leukocyte migration and adhesion, cell death and a thrombotic phenotype upon uremic conditions or uremic toxin treatment of endothelial cells. Cellular signaling pathways that were frequently activated included the ROS, MAPK/NF-κB, the Aryl-Hydrocarbon-Receptor and RAGE pathways. Overall, this review provides detailed insights into pathophysiological and molecular mechanisms underlying endothelial dysfunction in CKD. Targeting these pathways may provide new therapeutic strategies reducing increased the cardiovascular risk in CKD. 相似文献
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Heidi Kroemker 《International journal of human-computer interaction》2013,29(3-4):281-284
18.
Heidi Van den Broeck Hans De Wolf Ronny Blust 《The Science of the total environment》2009,407(8):3063-3069
In this study we present the results of an intersex survey of Littorina littorea along the Belgian coast. Levels of female intersex and sterility were determined to assess TBT related adverse effects. In addition, we determined the levels of male penis shedding and trematode infestation and investigated the morphology of the shell. Significant differences were found for all these variables which clearly differentiated periwinkles from Zeebrugge (B2) from those at other locations. Intersex index (ISI) values were relatively low (i.e. 0.00-0.39), except at B2 where they ranged up to 3.52, the highest value ever reported in literature. Consequently, female reproductive impairment at B2 was severe. Indeed, up to 95% of female periwinkles were sterile at B2. In addition, 61% of the male periwinkles had shed their penis. Furthermore, no trematode infestation could be detected at B2 and specimens from this location had the largest and heaviest shells, which may be related to population demography and/or a different use of energy budgets. 相似文献
19.
Radioprotection of mice by dietary squalene 总被引:1,自引:0,他引:1
Male C3H mice were fed a diet containing 2% squalene for 14 d prior to and 30 d subsequent to exposure to 6, 7 or 8 Gy of
whole body γ-irradiation (Cesium-137). After 14 d on squalene-supplemented diet, plasma and jejunal tissue squalene levels
were 2X and 15X that of controls. Seven days after irradiation, total white cell counts and total lymphocyte counts were substantially
depressed in a radiation dose-dependent manner. Although counts in the squalene group were consistently (18–119%) higher than
those in the corresponding dietary control group, the differences between dietary groups at any single dose were not significant.
Nuclear area of villus cells in the jejunum of both dietary groups was significantly reduced (20%) by day 11 post-irradiation
but the nuclear area in squalene-fed mice was significantly greater (15%) than in controls, before and after irradiation.
There were no differences in body weight as a function of either diet or radiation dose prior to the first observations of
animal lethality. Animal survival was decreased from 100 to 0% at 30 d post-irradiation by radiation doses of 6–8 Gy, with
the greatest difference between dietary groups being observed at 7 Gy (median survival times of 12 and 16 d for control and
squalene groups, respectively). Overall, survival of squalene-fed mice was significantly prolonged compared with control-fed
mice (P=0.0054 by censored multiple regression analysis). It is concluded that squalene conferred some cellular and systemic radioprotection
to mice receiving these lethal whole-body radiation doses. 相似文献
20.
Peters J Mac K Wichmann-Schauer H Klein G Ellerbroek L 《International journal of food microbiology》2003,88(2-3):311-314
Presently, enterococci take the third place of bacterial pathogens associated with nosocomial infections, after staphylococci and Escherichia coli. Especially, the resistances of enterococci to several available antibiotics are threatening. We attempted to determine which species of enterococci could be found in food of animal origin and their significance according to their antibiotic resistances for human beings. From November 2000 to May 2002 we investigated 155 samples of food of animal origin bought in retail outlets in Germany: 27 samples of sausages, 19 of ham, 83 of minced meat, 26 of cheese. From these food samples we isolated 416 enterococcal strains. The most frequent species was Enterococcus faecalis (299 strains); furthermore, we found Enterococcus faecium (54 strains), Enterococcus durans together with Enterococcus hirae (24 strains), Enterococcus casseliflavus (22 strains), Enterococcus avium (9 strains) and Enterococcus gallinarum (8 strains). We focused on the resistance patterns of 118 selected E. faecium and E. faecalis strains to 13 antimicrobial active agents (ampicillin, amoxicillin/clavulanic acid, avilamycin, chloramphenicol, enrofloxacin, erythromycin, flavomycin, gentamicin, penicillin, quinupristin/dalfopristin, teicoplanin, tetracycline and vancomycin). From the clinical point of view, the situation of antibiotic resistance to the examined antimicrobial agents seemed to be favourable. The investigated strains were sensitive to ampicillin and amoxicillin/clavulanic acid. These antibiotics are, in combination with an aminoglycoside, for example gentamicin, agents of choice for the treatment of enterococcal infections in human medicine. Only one E. faecium strain was resistant to penicillin, while all strains were sensitive to the glycopeptide antibiotics, vancomycin and teicoplanin. Resistances found against the antibiotics, tetracycline, quinupristin/dalfopristin and erythromycin, are causes for concern. 相似文献