981 resultados para Michigan Motor Car Manufacturing Company
Resumo:
Recent findings that spinal manual therapy (SMT) produces concurrent hypoalgesic and sympathoexcitatory effects have led to the proposal that SMT may exert its initial effects by activating descending inhibitory pathways from the dorsal periaqueductal gray area of the midbrain (dPAG). In addition to hypoalgesic and sympathoexcitatory effects, stimulation of the dPAG in animals has been shown to hal e a facilitatory effect on motor activity. This study sought to further investigate the proposal regarding SMT and the FAG by including a test of motor function in addition to the variables previously investigated, Using a condition randomised, placebo-controlled, double blind, repeated measures design, 30 subjects with mid to lon er cervical spine pain of insidious onset participated in the study. The results indicated that the cervical mobilisation technique produced a hypoalgesic effect as revealed by increased pressure pain thresholds on the side of treatment (P = 0.0001) and decreased resting visual analogue scale scores (P = 0.049). The treatment technique also produced a sympathoexcitatory effect with an increase in skin conductance (P < 0.002) and a decrease in skin temperature (P = < 0.02). There was a decrease in superficial neck flexor muscle activity (P < 0.0002) at the lower levels of a staged cranio-cervical flexion test. This could imply facilitation of the deep neck flexor muscles with a decreased need for co-activation of the superficial neck flexors, The combination of all findings,would support the proposal that SMT may, at least initially, exert part of its influence via activation of the PAG, (C) 2000 Harcourt Publishers Ltd.
Resumo:
Changes in trunk muscle recruitment have been identified in people with low-back pain (LBP). These differences may be due to changes in the planning of the motor response or due to delayed transmission of the descending motor command in the nervous system. These two possibilities were investigated by comparison of the effect of task complexity on the feedforward postural response of the trunk muscles associated with rapid arm movement in people with and without LBP. Task complexity was increased by variation of the expectation for a command to either abduct or flex the upper limb. The onsets of electromyographic activity (EMG) of the abdominal and deltoid muscles were measured. In control subjects, while the reaction time of deltoid and the superficial abdominal muscles increased with task complexity, the reaction time of transversus abdominis (TrA) was constant. However, in subjects with LBP, the reaction time of TrA increased along with the other muscles as task complexity was increased. While inhibition of the descending motor command cannot be excluded, it is more likely that the change in recruitment M of TrA represents a more complex change in organisation of the postural response.
Resumo:
Several problematic aspects of women's paid employment - e.g. low pay and lack of promotional opportunities - are exacerbated by the segregation of women and men into different occupations. In this article, the potential of in-store equal opportunities policies to break down such gender segregation will be explored, through consideration of the existence and implementation of these policies in twenty-two multinational retail companies in Dublin and Paris. It will be argued that, with one notable exception, the instore equal opportunities policies are effectively neutralized, and furthermore are neutralized in nationally specific ways which can be related to differences between France and Ireland in the organization of labour-market regulation and in women's labour-force participation (LFP). The case-study findings also suggest that the 'country' variable has a stronger effect on the existence and implementation of these policies than the extent of a shop's links to an overseas headquarters. The findings of this study have implications for both the equity of women's incorporation into the paid labour force and understanding of aspects of HRM in branches of multinational companies.
Resumo:
Forecasting category or industry sales is a vital component of a company's planning and control activities. Sales for most mature durable product categories are dominated by replacement purchases. Previous sales models which explicitly incorporate a component of sales due to replacement assume there is an age distribution for replacements of existing units which remains constant over time. However, there is evidence that changes in factors such as product reliability/durability, price, repair costs, scrapping values, styling and economic conditions will result in changes in the mean replacement age of units. This paper develops a model for such time-varying replacement behaviour and empirically tests it in the Australian automotive industry. Both longitudinal census data and the empirical analysis of the replacement sales model confirm that there has been a substantial increase in the average aggregate replacement age for motor vehicles over the past 20 years. Further, much of this variation could be explained by real price increases and a linear temporal trend. Consequently, the time-varying model significantly outperformed previous models both in terms of fitting and forecasting the sales data. Copyright (C) 2001 John Wiley & Sons, Ltd.
Resumo:
This paper focusing on the Chinese manufacturing sector assesses the environmental impact of trade liberalization in China. The results show that China's experience with the trade liberalization-environment nexus is consistent with international evidence. On one hand, trade liberalization has had various positive effects on the environment. Firstly, it promoted specialization in areas of comparative advantage, which, in general, included industries that contributed less to environmental degradation. Secondly, it allowed China to access and adopt the best international practices in pollution abatement technology. Thirdly, it enabled China to transfer environmental costs to other countries by importing intermediate products whose production contributed to environmental degradation. On the other hand, these positive effects were overwhelmed by a negative scale effect, which was the result of a huge increase in the demand for Chinese exports. The paper concludes that if China is to prevent pollution from reaching a critical threshold, environmental regulations need to be tightened. Copyright (C) 2002 John Wiley & Sons, Ltd and ERP Environment.
Resumo:
Alcoholism is a major health problem in Western countries, yet relatively little is known about the mechanisms by which chronic alcohol abuse causes the pathologic changes associated with the disease. It is likely that chronic alcoholism affects a number of signaling cascades and transcription factors, which in turn result in distinct gene expression patterns. These patterns are difficult to detect by traditional experiments measuring a few mRNAs at a time, but are well suited to microarray analyses. We used cDNA microarrays to analyze expression of approximately 10 000 genes in the frontal and motor cortices of three groups of chronic alcoholic and matched control cases. A functional hierarchy was devised for classification of brain genes and the resulting groups were compared based on differential expression. Comparison of gene expression patterns in these brain regions revealed a selective reprogramming of gene expression in distinct functional groups. The most pronounced differences were found in myelin-related genes and genes involved in protein trafficking. Significant changes in the expression of known alcohol-responsive genes, and genes involved in calcium, cAMP, and thyroid signaling pathways were also identified. These results suggest that multiple pathways may be important for neuropathology and altered neuronal function observed in alcoholism.
Resumo:
This article examines the productivity performance of Australia's manufacturing sector by decomposing its output growth into input growth, technological progress and gains in technical efficiency. This three-way decomposition is done with an improved version of the stochastic frontier model using eight, two-digit industry level data from 1968/9 to 1994/5. Empirical evidence shows that input growth fueled output growth from 1968/9 to 1973/4, but since then, total factor productivity (TFP) growth has been the main contributor of output growth. While the trend of TFP growth was found to be promising for most industries with positive and increasing technological progress, the negative gains from technical efficiency over time is however cause for concern.