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71.
The debate about experience-based or tacit knowledge has focused much attention on the limits to formalisation of work process
knowledge. A main line of argument has been that, for example, industrial work even with highly advanced technical equipment
can only be performed adequately when the worker through experience on the job has gained a feel for the functioning of the
machinery and the properties and behaviour of the materials. In this debate links tend to be created between on the one hand
formalised-abstracted-verbal knowledge as opposed to on the other hand informalised-concrete-tacit knowledge. We have worked
for some years with the design of training materials which at its core have video documentation of best practice as we have
found it at work. In this paper we will present and discuss experience with design and use of a hypermedia type training material,
SPRING to be used by new machine setters in the spring industry. Based on our own experience we will argue for the relevance
of this type of training materials as a means of supporting reflection and dialogue in the community of practitioners. 相似文献
72.
Lipoprotein lipase regulates the hydrolysis of circulating triglyceride and the uptake of fatty acids by most tissues, including the mammary gland and adipose tissue. Thus, lipoprotein lipase is critical for the uptake and secretion of the long-chain fatty acids in milk and for the assimilation of a high-fat milk diet by suckling young. In the lactating female, lipoprotein lipase appears to be regulated such that levels in adipose tissue are almost completely depressed while those in the mammary gland are high. Thus, circulating fatty acids are directed to the mammary gland for milk fat production. Phocid seals serve as excellent models in the study of lipoprotein lipase and fat transfer during lactation because mothers may fast completely while secreting large quantities of high fat milks and pups deposit large amounts of fat as blubber. We measured pup body composition and milk fat intake by isotope (deuterium oxide) dilution and plasma post-heparin lipoprotein lipase activity in six grey seal (Halichoerus grypus) mother-pup pairs at birth and again late in the 16-day lactation period. Maternal post-heparin lipoprotein lipase activity increased by an average of four-fold by late lactation (P = 0.027), which paralleled an increase in milk fat concentration (from 38 to 56%; P = 0.043). Increasing lipoprotein lipase activity was correlated with increasing milk fat output (1.3-2.1 kg fat per day) over lactation (P = 0.019). Maternal plasma triglyceride (during fasting) was inversely correlated to lipoprotein lipase activity (P = 0.027) and may be associated with the direct incorporation of long-chain fatty acids from blubber into milk. In pups, post-heparin lipoprotein lipase activity was already high at birth and increased as total body fat content (P = 0.028) and the ratio of body fat: protein increased (P = 0.036) during lactation. Although pup plasma triglyceride increased with increasing daily milk fat intake (P = 0.023), pups effectively cleared lipid from the circulation and deposited 70% of milk fat consumed throughout lactation. Lipoprotein lipase may play an important role in the mechanisms involved with the extraordinary rates of fat transfer in phocid seals. 相似文献
73.
Preliminary investigations have been made in normally hearing alert adults to establish whether the 40 Hz modulation-following response (MFR) can be used to predict 400 Hz uncomfortable loudness levels (ULLs). The MFR stimulus was a 400 Hz carrier, amplitude- and frequency-modulated by a 40 Hz sine function. Subjective ULLs were obtained using standard procedures. Objective ULLs were obtained from MFR parameter intensity functions using rms amplitude, phase angle and magnitude-squared coherence (40 Hz components). The best predictions of the subjective ULL were made using objective ULLs calculated from the gradients of linear best-fit lines for individual phase-intensity functions (80 per cent predicted within 10 dB of the subjective ULL; maximum deviation=16 dB). Poorest predictions were based on inter-subject average rms amplitude-intensity functions, where as few as 14 per cent were within 10 dB of the subjective value. The best predictions were considered sufficiently accurate to warrant further investigation using a variety of modulation and carrier frequencies in different age groups and with varying degrees of hearing loss. 相似文献
74.
75.
Data from an anonymous survey of 3,690 adolescents were used to assess how much of the unique variance in adolescents' self-reported drug use was accounted for by number of parents in comparison to the adolescents' sex, age, social class, and peer drug use. Multiple regression revealed that the contribution of number of parents was small and nonsignificant compared to peer use, student age, parental occupation and remarriage, student sex, and parental unemployment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
77.
FG Surawicz DR Brightwell WD Weitzel E Othmer 《Canadian Metallurgical Quarterly》1976,133(11):1306-1309
The authors review recent and current literature on the relationship between psychological factors and cancer. They discuss the roles of predisposing personality patterns and emotional stress in the development, site, and course of cancer; the influence of awareness of terminal illness on the behavior of cancer patients; and the management of psychiatric symptoms in these patients. 相似文献
78.
The results obtained by testing 3127 mink sera as well as the analysis of families completely confirmed that the Lpm allotype system of very high density proteins is under genetic control, as postulated earlier. The polymorphism of the first five allotypes is due to the genetic units Lpm1, Lpm4, Lpm1,2, Lpm3,4 and Lpm2,4,5, which behave as Mendelian alleles. The data obtained suggest the existence of an additional gene, LpmX, which, in the homozygous state, determines a very rare phenotype, negative for the first five markers. 相似文献
79.
K Jentzsch H Binder H Cramer DL Glaubiger RM Kessler C Bull TC Pomeroy NL Gerber 《Canadian Metallurgical Quarterly》1981,47(6):1267-1278
Twenty-nine patients with Ewing's sarcoma of the lower extremity who survived for two or more years following therapy (5000 rad locally and systemic chemotherapy) were studied to assess functional status of the affected leg. Twenty-two of twenty-nine were alive and were reexamined; the deceased patients were evaluated by record review. Twenty-two of the twenty-nine had serial radiographs, which were reviewed to assess growth change induced by radiation. The living patients were divided on the basis of clinical examination into four functional groups with Group I comprising patients with minor functional limitations and leg length discrepancy 1.5 cm or less. Group II patients had moderate functional limitations with 2.5-cm leg-length discrepancy or less. Group III patients had severe functional limitations with up to 4-cm leg length discrepancy. Group IV patients had severe complications, sufficient enough to warrant amputation. Thirteen of twenty-two patients were classified as functional Group I, five as Group II, three as Group III, and one as Group IV. Radiographic changes in growing bone did not correlate with functional results. Although a femoral fracture and an age less than 16 years at diagnosis were found to be less favorable prognostic factors for the functional treatment result, these results show that neither femoral location nor young age justify primary amputation for Ewing's sarcoma of the lower leg extremity. 相似文献
80.