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21.
Recent research suggests that implementing information systems presents considerable difficulties and that many implementations are total or partial failures. This paper argues that what both practitioners and students require are richer and more acceptable models of information systems implementation. Accordingly, case study data concerning the introduction of manufacturing resource planning (MRP II) are used to illustrate five patterns of behaviour (rites) which capture important social actions; and four components of changing psychological orientation. It is argued that appreciation of the rites and psychological developments identified here will support effective change programmes. Guidelines based on our model are provided for practitioners. 相似文献
22.
FY Ghauri JK Nicholson BC Sweatman J Wood CR Beddell JC Lindon NJ Cairns 《Canadian Metallurgical Quarterly》1993,6(2):163-167
Mutations of ras oncogenes in 37 human stomach cancers and 13 adenomas were investigated with regard to the histological phenotypes using polymerase chain reaction (PCR), allele-specific oligonucleotide hybridization and/or direct sequencing of the PCR products. The ras mutation was found only in one case (2.7%), the histology of which was poorly differentiated adenocarcinoma. We found no mutation in stomach adenomas. The mutation consisted of a guanine-to-adenine transition in the first base of codon 13 of c-Ki-ras which replaced wild-type glycine with serine, indicating that a putative glycine-to-aspartic acid change is not necessarily the critical event for c-Ki-ras gene activation in codon 13. These results further confirm the infrequency of ras mutation in stomach tumors and also suggest that ras mutations are not specific to the differentiated type of stomach cancer. 相似文献
23.
Lewinsohn Peter M.; Hops Hyman; Roberts Robert E.; Seeley John R.; Andrews Judy A. 《Canadian Metallurgical Quarterly》1993,102(4):517
Reports an error in the original article by P. M. Lewinsohn et al ( Journal of Abnormal Psychology, 1993[Feb], Vol 102[1], 133–244). On page 140, in the Total Incidence columns in Table 4, the data for the Attention Deficit row should be switched with that for the Conduct row. (The following abstract of this article originally appeared in record 1993-25780-001.) Data were collected on the point and lifetime prevalences, 1-yr incidence, and comorbidity of depression with other Diagnostic and Statistical Manual of Mental Disorders-III-Revised (DSM-III-R) disorders in a randomly selected sample (n?=?1,710) of high school students at point of entry and at 1-yr follow-up (n?=?1,508). The Schedule for Affective Disorders and Schizophrenia for School-Age Children was used to collect diagnostic information; 9.6% met criteria for a current disorder, more than 33% had experienced a disorder over their lifetimes, and 31.7% of the latter had experienced a 2nd disorder. High relapse rates were found for all disorders, especially for unipolar depression (18.4%) and substance use (15.0%). Female Ss had significantly higher rates at all age levels for unipolar depression, anxiety disorders, eating disorders, and adjustment disorders; male Ss had higher rates of disruptive behavior disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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25.
A.J. Roberts 《Computer Physics Communications》1997,100(3):215-230
I describe a method, particularly suitable to implementation by computer algebra, for the derivation of low-dimensional models of dynamical systems. The method is systematic and is based upon centre manifold theory. Computer code for the algorithm is relatively simple, robust and flexible. The method is applied to two examples: one a straightforward pitchwork bifurcation, and one being the dynamics of thin fluid films. 相似文献
26.
27.
National and regional corporate spatial structure 总被引:3,自引:0,他引:3
Much is known about the macro-impacts of business activities on national and regional economies; however, comparatively little
is known at the micro level about the impact spatial agglomeration of corporate wealth and performance has on urban systems.
This paper reports on a collaborative research project between the Australian Housing and Urban Research Institute and Dun
and Bradstreet, an international financial credit agency, to analyse the spatial implications of corporate structure in metropolitan
regions. This paper analyses spatial patterns of medium to large businesses in three Australian State capital cities at the
postcode level in order to assess the agglomeration of corporate capital, sales, and performance. The research indicates that
ratio analysis can provide a useful insight into the competitiveness of metropolitan regions and the control corporate headquarters
have over decision making and investment processes. The findings of this research are of special interest to capital markets,
business and urban researchers in the Asia Pacific Region.
Received: September 1997/Accepted: September 2001 相似文献
28.
AF Minnick MJ Roberts WB Young RM Kleinpell RJ Marcantonio 《Canadian Metallurgical Quarterly》1997,35(4):399-409
OBJECTIVES: Market forces make it essential to know what policies and actions influence patients' reports of hospital services. No studies have examined the role of patient characteristics, labor quality and staff characteristics, nonlabor resources, managerial practices, and employee attitudes within a single investigation. METHODS: The authors collected, simultaneously, data about labor, management and service processes, nonlabor resources, and employee attitudes on 117 nonintensive medical-surgical inpatient units in 17 hospitals selected from a pool of 69 institutions within a metropolitan area by a stratified random sample. Of the 2,595 patients who agreed to participate, 2,051 (79%) completed telephone interviews regarding their experiences with physical care, education, and pain management services within 26 days of hospital discharge. RESULTS: A significant amount of variation in patients' service reports was explained (adjusted R2 = 0.41 physical care, 0.35 pain management, 0.44 education). Although the predictors varied for each service report, patient characteristics, especially those related to personal resources, had a large explanatory role. A labor assignment pattern that could explain why earlier studies found labor quality and staff characteristics to have only a weak role in the prediction of patients' service reports was noted. CONCLUSIONS: The results related to patient characteristics may indicate opportunities to improve care by confronting service design strategies that erroneously rely on a homogeneous patient population. Measurement challenges identified by this study must be addressed to determine the role of labor quantity and staff characteristics. 相似文献
29.
30.
OBJECTIVE: To estimate the extent to which cigarette smokers who switch to cigars or pipes alter their risk of dying of three-smoking related diseases-lung cancer, ischaemic heart disease, and chronic obstructive lung disease. DESIGN: A prospective study of 21520 men aged 35-64 years when recruited in 1975-82 with detailed history of smoking and measurement of carboxyhaemoglobin. MAIN OUTCOME MEASURES: Notification of deaths (to 1993) classified by cause. RESULTS: Pipe and cigar smokers who had switched from cigarettes over 20 years before entry to the study smoked less tobacco than cigarette smokers (8.1 g/day v 20 g/day), but they had the same consumption as pipe and cigar smokers who had never smoked cigarettes (8.1 g) and had higher carboxyhaemoglobin saturations (1.2% v 1.0%, P < 0.001), indicating that they inhaled tobacco smoke to a greater extent. They had a 51% higher risk of dying of the three smoking related diseases than pipe or cigar smokers who had never smoked cigarettes (relative risk 1.51; 95% confidence interval 0.96 to 2.38), a 68% higher risk than lifelong non-smokers (1.68; 1.16 to 2.45), a 57% higher risk than former cigarette smokers who gave up smoking over 20 years before entry (1.57; 1.04 to 2.38), and a 46% lower risk than continuing cigarette smokers (0.54; 0.38 to 0.77). CONCLUSION: Cigarette smokers who have difficulty in giving up smoking altogether are better off changing to cigars or pipes than continuing to smoke cigarettes. Much of the effect is due to the reduction in the quantity of tobacco smoked, and some is due to inhaling less. Men who switch do not, however, achieve the lower risk of pipe and cigar smokers who have never smoked cigarettes. All pipe and cigar smokers have a greater risk of lung cancer than lifelong non-smokers or former smokers. 相似文献