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11.
Van Der Molen HF Kuijer PP Hopmans PP Houweling AG Faber GS Hoozemans MJ Frings-Dresen MH 《Ergonomics》2008,51(3):355-366
The effect of block weight on work demands and physical workload was determined for masons who laid sandstone building blocks over the course of a full work day. Three groups of five sandstone block masons participated. Each group worked with a different block weight: 11 kg, 14 kg or 16 kg. Productivity and durations of tasks and activities were assessed through real time observations at the work site. Energetic workload was also assessed through monitoring the heart rate and oxygen consumption at the work site. Spinal load of the low back was estimated by calculating the cumulated elastic energy stored in the lumbar spine using durations of activities and previous data on corresponding compression forces. Block weight had no effect on productivity, duration or frequency of tasks and activities, energetic workload or cumulative spinal load. Working with any of the block weights exceeded exposure guidelines for work demands and physical workload. This implies that, regardless of block weight in the range of 11 to 16 kg, mechanical lifting equipment or devices to adjust work height should be implemented to substantially lower the risk of low back injuries. 相似文献
12.
JO Larsson G Aurelius L Nordberg PA Rydelius R Zetterstr?m 《Canadian Metallurgical Quarterly》1996,85(12):1450-1455
Home visiting is a part of the Swedish child health surveillance programme. In the present study, part of a longitudinal prospective project, the predictive power of observations at home visits to 338 newborn babies was evaluated. The regular home visit was made by the nurse at a Child Welfare Centre also using a check-list developed for this project. Her check-list assessments seemed valid in identifying families with stressful psychosocial conditions. When the general home situation was judged as "poor" or "dubious", the boys showed signs of a delayed mental development at 4-5 years of age. Assessments of "feeding problems" among boys were associated with behavioural problems at 4-5 years of age. The results underline the importance of an early home visit as a base for the developmental surveillance at Child Welfare Centres. However, the results of the home visit observations were not followed by any extra interventions at CWC. It seems the nurse should feel confident in her check-list judgement and initiate interventions where appropriate. 相似文献
13.
Jørgensen MB Faber A Jespersen T Hansen K Ektor-Andersen J Hansen JV Holtermann A Søgaard K 《Ergonomics》2012,55(7):762-772
This study evaluates the implementation of physical coordination training (PCT) and cognitive behavioural training (CBTr) interventions in a randomised controlled trial at nine cleaners' workplaces. Female cleaners (n = 294) were randomised into a PCT, a CBTr or a reference (REF) group. Both 12-week interventions were performed in groups guided by an instructor. Records were kept on intervention dose (adherence) unanticipated events at the work place (context) and quality of intervention delivery (fidelity). Participant adherence was 37% in the PCT and 49% in the CBTr interventions. Optimal implementation was reached by only 6% in PCT and 42% in the CBTr. Analysis of the barriers to successful implementation indicated that the intervention process is sensitive to unanticipated events. In order to succeed in improving the health of high-risk populations such as cleaners and to correctly interpret intervention effects, more research on implementation is needed. Trial registration: ISRCTN96241850. PRACTITIONER SUMMARY: Both physical coordination training and cognitive behavioural training are potential effective workplace interventions among low educated job groups with high physical work demands. However, thorough consideration should be given to feasibility in the design of interventions. The optimal intervention should be tailored to closely match the implementation context and be robust and flexible to minimise susceptibility to changes in work organisation. 相似文献
14.
M. Faber Frank Jst Reiner Manstetten Georg MüllerFürstenberger 《Advanced Synthesis \u0026amp; Catalysis》1996,338(1):497-505
Joint Production and Environmental Policy: A Case Study for the Chlorine and Sulphuric Acid Industry The chemical industry is a key sector of industrialised economy. Thus, environmental policy with a focus on the chemical industry is likely to affect the economy as a whole. In this article we show, that environmental regulation of the chemical industry has major consequences for other production sectors. Two major problem areas of the chemical industry are considered: the chlorine industry and the sulphur industry. While the chlorine industry can cope with environmental legislation by process and product innovation without a substantial impact on other sectors, this is not the case with the sulphur industry. The production of its key product, sulphuric acid, utilises joint products of other sectors as inputs. The chemical industry offers these sectors the possibility to dispose of their unwanted by-products. Environmental policy, directed towards a reduction of sulphuric acid is likely to cause a waste disposal problem in sectors which manufacture sulphur or sulphur dioxide as by-products. Solving environmental problems within the chemical industry therefore creates new problems in other sectors. 相似文献
15.
An emulsion-type product was prepared to determine the effect of irradiation on lipid and cholesterol oxidation, color change, and volatile production in raw pork with different fat contents. Lipid oxidation increased with an increase in fat content or irradiation dose. Irradiated batters had higher cholesterol oxides than nonirradiated, and the major cholesterol oxides formed in irradiated pork batters were 7α- and 7β-hydroxycholesterol. Hunter color a- and b-values of raw pork batters were decreased by irradiation regardless of fat content. Irradiation increased the amount ofvolatiles significantly. Although lipid oxidation of high fat products (10 and 15% fat) was higher than that of low fat products (4%), high fat products did not always produce greater amount of volatiles. In summary, irradiation increased lipid and cholesterol oxidation, volatiles production and had detrimental effects on the color of raw pork batters under aerobic condition. 相似文献
16.
17.
MP Lewis M Clements S Takeda PL Kirby H Seki LB Lonsdale MH Sullivan MG Elder JO White 《Canadian Metallurgical Quarterly》1996,17(2-3):137-146
High doses of morphine produce a state of behavioural inactivity and muscular rigidity. This type of 'catalepsy' is clearly different from the state which is produced by the administration of neuroleptics, e.g. haloperidol. While haloperidol-induced catalepsy can easily be antagonised by NMDA receptor antagonists, there has been a report that the non-competitive NMDA receptor antagonist (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d] cyclohepten-5,10-imine (MK-801) potentiates morphine-induced catalepsy. The aim of this study was to further examine the role of glutamate receptors in the mediation of morphine-induced catalepsy. To this end we coadministered morphine (20, 40, 60 mg/kg i.p.) with MK-801 (0.1 and 0.3 mg/kg i.p.), the competitive NMDA receptor antagonist DL-(E)-2-amino-4-methyl-5-phosphono-3-pentoic acid (CGP 37849) (2 and 6 mg/kg i.p.), or 1-(4-aminophenyl)-4-methyl-7,8-methylen-dioxy-5H-2,3- benzodiazepine (GYKI 52466) (2 and 4 mg/kg), an antagonist of the AMPA type of glutamate receptors, respectively. The degree of catalepsy was assessed using two different methods, the 'bar/podium/grid' test which is commonly used to measure neuroleptic-induced catalepsy, and a test for the presence or absence of righting reflexes after turning the animals into a supine position. It was found that in the 'bar/podium/grid' test coadministration of both NMDA receptor antagonists significantly and dose-dependently augmented morphine-induced catalepsy. The results using the AMPA receptor antagonist were less clear since the lower dose of GYKI 52466 tended to attenuate the morphine effect whereas the higher dose augmented morphine-induced catalepsy in some cases. While placing the animals on the bar and on the podium produced essentially the same results, the grid was found to be inapplicable for the measurement of morphine-induced catalepsy since the animals did not cling to the grid and fell off almost immediately after being released from the experimenter's hand. With respect to the righting reflexes it was found that the number of animals not showing these responses increased when MK-801 or CGP 37849 was coadministered with morphine. In contrast, most of the animals treated with GYKI 52466 and morphine displayed intact righting reflexes. It is concluded that glutamatergic transmission plays an important role in the mediation of morphine-induced catalepsy, though different to that of haloperidol-induced catalepsy, and that NMDA and AMPA receptors are differentially involved in different aspects of the associated behavioural state. 相似文献
18.
Rasmussen's encephalitis is a rare progressive pediatric epileptic syndrome. Recent evidence from experimental animals and patients with the disease suggests an important role for both humoral and cell-mediated immune mechanisms in the pathogenesis of this disease. The glutamate receptor subunit GluR3 may be an important autoantigen in the disease. (This review has been modified from a review published in Current Opinion in Neurology 1996, 9:141-145.) 相似文献
19.
Z Mourelatos JO Gonatas LM Nycum NK Gonatas JA Biegel 《Canadian Metallurgical Quarterly》1995,28(2):354-355
20.