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951.
Innovators and imitators: Organizational reference groups and adoption of organizational routines 总被引:3,自引:0,他引:3
Firms vary greatly in their rates of creating and adopting technological and organizational innovations, in part because of their choice of reference group. We argue that the selection of a reference group is a crucial and neglected source of firm heterogeneity. Comparisons to the average of other firms in a population cause most firms to adopt innovations once they are widely accepted. A distinctive feature of the minority of innovating firms that create innovations or adopt them early is that they compare themselves with, compete with, and try to differ from other innovating firms, whereas the majority of firms compare themselves with, and conform to, a broader group of firms. We elaborate this argument based on the behavioral theory of the firm and institutional theory, and test it on a two-period survey on adoptions of innovative organizational forms in Europe and the US. The analysis shows the predicted differences in the adoption patterns of innovating and imitating firms. 相似文献
952.
R. Chawla Navendu Goyal Rajneesh Calton Shweta Goyal 《Indian journal of clinical biochemistry : IJCB》2006,21(1):77-82
Early identification of patients with acute myocardial infarction is of prime importance due to the associated very high mortality.
Only 22% of the patients presenting at emergency cardiology care with chest pain have coronary disease. A number of biochemical
tests like CKMB and Troponin-T/I have been introduced for early detection of the coronary syndrome (ACS). Ischemia modified
albumin (IMA) has been recently introduced as a marker of myocardial ischemia. We estimated serum IMA in four sequential samples
from 25 patients admitted to ICCU. Twenty five healthy volunteers formed the control group from which the normal range was
derived. IMA was significantly raised in ischemia patients than in controls as well as compared to the patients who did not
have cardiac ischemia. IMA demonstrated good discrimination between the ischemic and the non-ischemic patients with an Odds
Ratio of 16.9 (6.29–46.87) than CKMB which showed an Odds Ratio of 2.07 (1.18–6.08). Sensitivity and specificity of IMA for
the detection of ACS was 78.0% and 82.7% compared to 58.0% and 60.0%, respectively for the CK-MB assay. The area under the
ROC curve of IMA for ischemic v/s non-ischemic patients was 0.834. IMA appears to be developing into a new and very potent
marker, of cardiac ischemia. 相似文献
953.
954.
The enzyme theory and the origin of biochemistry 总被引:3,自引:0,他引:3
955.
Technological agglomeration and the emergence of clusters and networks in nanotechnology 总被引:3,自引:0,他引:3
Research and development at the nanoscale requires a large degree of integration, from convergence of research disciplines in new fields of enquiry to new linkages between start-ups, regional actors and research facilities. Based on the analysis of two clusters in nanotechnologies (MESA+ (Twente) and other centres in The Netherlands and Minatec in Grenoble in France), the paper discusses the phenomenon of technological agglomeration: co-located scientific and technological fields associated to coordinated technology platforms to some extent actively shaped by institutional entrepreneurs. Such co-location and coordination are probably a pre-requisite for the emergence of strong nanoclusters. 相似文献
956.
M. V. R. Reddy R. Alli B. C. Harinath 《Indian journal of clinical biochemistry : IJCB》2000,15(1):127-135
Lymphatic filariasis caused mainly by infection fromWuchereria bancrofti andBrugia malayi remains as the major cause of clinical morbidity in tropical and subtropical countries. Development of vaccine against filarial infection can act as additional measure to the existing therapeutic and vector control methods in the control of this disease. The main hurdles in the development of anti-filarial vaccine are the strict primate specificity ofWuchereria bancrofti, the paucity of parasite material, the diversity of clinical manifestations and their associated complex immune responses, lack of clear understanding on host-parasite interactions and the mechanisms involved in protective immunity. However in the past few years, the information generated in immuno-epidemiological studies, correlated with observations in experimental animals suggests that a filarial vaccine is feasible. Initially live irradiated infective larvae have been successfully used to induce high level of protective immunity in several animal models. Applying diverse strategies, variety of purified or recombinant filarial antigens have been explored for their ability to induce protection in different host-parasite systems. Some of these targeted filarial antigens induced high level of resistance in experimental animals against challenge infections. More focussed studies on thorough characterization of parasitological and immunological changes associated with resistance induced by such candidate protective antigens and on delivery mechanisms and safety aspects will be crucial in their selection for possible use in humans. 相似文献
957.
In the United States, Congress has had a long-standing interest in consumer privacy and the extent to which company practices are based on fair information practices. Previously, public policy was largely informed by anecdotal evidence about the effectiveness of industry self-regulatory programs. However, the Internet has made it possible to unobtrusively sample web sites and their privacy disclosures in a way that is not feasible in the offline world. Beginning in 1998, the Federal Trade Commission relied upon a series of three surveys of web sites to assess whether organizations post online privacy disclosures and whether these disclosures represent the U.S. definition of fair information practices. While each year's survey has provided an important snapshot of U.S. web-site practices, there has been no longitudinal analysis of the multiyear trends. This study compares a subset of equivalent individual-level web-site data for the 1998, 1999, 2000, and 2001 web surveys. Implications for using this type of research to inform public policy are discussed. 相似文献
958.
From a number of ML estimators (typically unbiased) of practical interest which include the variance for a Gaussian distribution, the standard deviation for a Laplace distribution, the variance for a Rayleigh distribution and a “spread parameter” for a Cauchy distribution, we design robust estimators according to an emphasis balance between normalized performance and normalized robustness. We measure performance with inverted MSE and robustness with a differential geometric approach. 相似文献
959.
In previous work it was established that the U.K. tractor industry was characterised by a high degree of technical change and that this was brought about by a process of more or less continuous incremental innovation. What was lacking was an analysis of how much technical change had been introduced and an indication of the role played by technical change in determining the performance of the U.K. tractor industry internationally. This paper concludes that on the average technical change in the industry had increased by as much as 150 percent during the years 1959–1977, though there is some indication that the rate of change might now be slowing somewhat.In order to determine the relative importance of technical change a method was developed to operationalise the distinction between price and non-price competition as well as the idea of intrinsic (technical) and associative (non-technical) factors as constituents of the latter. Based on cross-sectional data for the year 1978, it has been possible to show that British manufacturers tend to produce moderately priced tractors of low to medium technical sophistication: that German manufacturers produced the most technically sophisticated tractors; that the Italian manufacturers are not generally more sophisticated, technically, than the British producers except with respect to their development of four-wheel drive; and that COMECON-based producers combine a very low price with some degree of technical sophistication. Finally, it has been possible to show that the tractors with the highest sales are among the less sophisticated in each of the power ranges investigated and that new entrants used technical sophistication as an element of their entry strategy. The answer to the question of what allows the market leader to be market leader required the development of measures for associative non-price factors, such as the availability of a dealer network brand loyalty, resale prices of tractor models, etc. By performing a regression analysis on these measures along with previously derived measures of quality-adjusted price and relative technical sophistication it has been possible to show that market leadership is achieved as a result of a balance of a number of factors, the most important of which are the size of the dealer network, warrants cost, advertising, technical sophistication and price. 相似文献
960.
Are preservice teachers prepared to teach struggling readers? 总被引:1,自引:0,他引:1
Reading disabilities such as dyslexia, a specific learning disability that affects an individual’s ability to process written
language, are estimated to affect 15–20% of the general population. Consequently, elementary school teachers encounter students
who struggle with inaccurate or slow reading, poor spelling, poor writing, and other language processing difficulties. However,
recent evidence may suggest that teacher preparation programs are not providing preservice teachers with information about
basic language constructs and other components related to scientifically based reading instruction. As a consequence preservice
teachers have not exhibited explicit knowledge of such concepts in previous studies. Few studies have sought to assess preservice
teachers’ knowledge about dyslexia in conjunction with knowledge of basic language concepts. The purpose of the present study
was to examine elementary school preservice teachers’ knowledge of basic language constructs and their perceptions and knowledge
about dyslexia. Findings from the present study suggest that preservice teachers, on average, are able to display implicit
skills related to certain basic language constructs (i.e., syllable counting), but fail to demonstrate explicit knowledge
of others (i.e., phonics principles). Also, preservice teachers seem to hold the common misconception that dyslexia is a visual
perception deficit rather than a problem with phonological processing. Implications for future research as well as teacher
preparation are discussed. 相似文献