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71.
Philipp Koellinger 《Research Policy》2008,37(8):1317-1328
This article analyzes the relationship between the usage of Internet-based technologies, different types of innovation, and performance at the firm level. Data for the empirical investigation originates from a sample of 7302 European enterprises. The empirical results show that Internet-based technologies were an important enabler of innovation in the year 2003. It was found that all studied types of innovation, including Internet-enabled and non-Internet-enabled product or process innovations, are positively associated with turnover and employment growth. Firms that rely on Internet-enabled innovations are at least as likely to grow as firms that rely on non-Internet-enabled innovations. Finally, it was found that innovative activity is not necessarily associated with higher profitability. Possible reasons for this and implications are discussed. 相似文献
72.
In Experiment 1, short-term memory for lists of visual stimuli was studied in four squirrel monkeys (Saimiri sciureus). A delayed-matching procedure was used in which a subject was presented with lists containing one, three, or six stimulus patterns, and memory for serial positions was probed by requiring the subject to choose between a list item and a nonlist item. The rate of item presentation was varied, as was the delay between the final item on a list and the retention test. In Experiment 2, the same procedures were used to compare recognition memory in four monkeys and four humans. Although differences in the levels and shapes of the serial-position curves appeared between species, both monkeys and humans showed primacy and recency effects. The presentation time of stimuli had a negligible effect on performance in both monkeys and humans, whereas delay significantly affected human retention but not monkey retention. 相似文献
73.
Philippe B. Katchunga Patrick N. Mirindi Antoine S. Kishabongo Justin C. Cikomola Socrate Bwanamdogo Jan Philippé Marijn M. Speeckaert Joris R. Delanghe 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2015,25(3):469-473
Introduction
Diagnosis and monitoring of diabetes mellitus in sub-Saharan Africa, based on blood analyses, are hampered by infrastructural and cultural reasons. The first aim of this study was to evaluate the diagnostic accuracy of glycated nail proteins for diabetes mellitus. The second aim was to compare the course of short- and long-term glycemic biomarkers after 6 months of antidiabetic treatment. These objectives should support our hypothesis that glycated nail proteins could be used as an alternative glycemic biomarker.Materials and methods
This case-control study consisted of 163 black diabetics and 67 non-diabetics of the South Kivu (Democratic Republic of Congo). Diagnostic accuracy of glycated nail proteins was evaluated using ROC curve analysis. At the start of the study, glycated nail protein concentrations were compared between diabetics and non-diabetics, using a nitro blue tetrazolium (NBT) colorimetric method. In a subgroup of 30 diabetics, concentrations of glycated nail proteins, fasting glucose (Accu-Chek® Aviva), serum fructosamine (NBT) and HbA1c (DCA-2000+®) were measured at start and after 6 months.Results
ROC analysis yielded an AUC of 0.71 (95% confidence interval (CI): 0.65-0.76) and a cut-off point of 3.83 μmol/g nail. Concentration of glycated nail proteins was significantly higher (P < 0.001) in diabetics in comparison with non-diabetics. After 6 months of antidiabetic treatment, a significant drop in the fasting glucose concentration (P = 0.017) and concentration of glycated nail proteins (P = 0.008) was observed in contrast to serum fructosamine and HbA1c.Conclusions
Measurement of glycated nail proteins could be used to diagnose and monitor diabetes mellitus in sub-Saharan Africa.Key words: fasting glucose concentration, fructosamine, hemoglobin A1c protein, nails, sub-Saharan Africa, diabetes mellitus 相似文献74.
This paper investigates the specific planning environment of an automotive part manufacturer and characterizes this environment based on variables regarding the product,its demand and the manufacturing process.The fit of different planning methods,namely material requirements planning,reorder point,cyclic planning,kanban,and heijunka to this specific planning environment is analyzed and evaluated by exploratory research.The results show that different product characteristics make it hard to apply a single planning method.None of the investigated methods show the ability to cover the complex requirements of a combined planning environment of two partly divergent product types with a deep value chain. 相似文献