Guidelines for energetic load in three methods of refuse collecting

The energetic load and guidelines were formulated for energetic load in three methods of refuse collecting. These methods were collecting refuse in polythene bags (in a city area and in a suburb), in two-wheeled mini-containers and in large four-wheeled containers. To determine the energetic load of the collecting methods, these collecting methods were simulated in the laboratory. The simulation protocols were based on data such as weight of the handled materials, and the frequency and duration of the most prominent refuse collecting activities as found in the preliminary field study. During the execution of the protocols the heart rate and oxygen uptake were continuously recorded. The maximal oxygen uptake was determined during a continuous running protocol on a treadmill. The energetic load was expressed in terms of percentage of the maximal oxygen uptake. As the limit for the energetic load a value of 30% of the maximal oxygen uptake during an 8-h working day was chosen. The limit for energetic overload was exceeded for the maximal oxygen uptake for refuse collecting with polythene bags in a city area (44·5%), collecting with bags in a suburb (37·2%) and with mini-containers. The percentage of the maximal oxygen uptake for collecting with large containers was 28·4%, which was below the limit for the energetic load of 30%. Guidelines were formulated for the relevant occupational field terms: maximal amount of collecting hours and maximal amount of collected refuse per collector per hour. The guidelines were formulated in percentiles (P₉₀ and P₇₅). This means that 90 and 75% of the refuse collecting population in The Netherlands will be prevented from having an energetic overload above the limit of 30% of the maximal oxygen uptake.     

Factors affecting ambulatory heart rate in industrial workers†

The influence of several factors on the heart-rate (HR) response to tasks performed during regular work has been evaluated in a study population of 1654 male factory employees in Israel. Each worker was monitored for approximately one hour with an ambulatory electrocardiogram. The percentage change from resting HR decreased with increasing age and, as expected, was lower in sedentary workers than in manual workers. A highly significant negative correlation between the HR response and both systolic and diastolic blood pressure was found in the manual workers only. In further multiple regression analysis, after controlling for age, relative weight, smoking status, resting HR and the presence of abnormalities on the resting ECG, the association persisted for systolic BP only. Among young workers, both smoking and relative body weight were significantly associated with a higher HR response to work. Those with ECG abnormalities had lower HR response than those with normal ECGs, but not significantly so. These findings indicate that for roughly equivalent tasks and levels of resting HR, the HR response to regular work is influenced by several constitutional and behavioural factors. It may therefore be important to consider these factors when assigning workers to tasks involving strenuous effort.     

Metabolic costs of load carriage with different container sizes

Abstract

Six well-trained male subjects carried boxes of varying box width and weight at varying speeds on a level treadmill until steady-state heart rates were obtained. Analysis of the steady-state data for heart rate and metabolic cost led to development of highly accurate predictor models for both factors. The metabolic-cost model accounted for over 94% of the variance (R²>0·94), and the heart-rate model accounted for over 81% of the variance present (R²>0·81). Evaluation of other models for predicting physiological response to carrying loads found their predictions to differ significantly from the data of the present study.     

The influence of music on mood and performance while driving

Mood can influence our everyday behaviour and people often seek to reinforce, or to alter their mood, for example by turning on music. Music listening while driving is a popular activity. However, little is known about the impact of music listening while driving on physiological state and driving performance. In the present experiment, it was investigated whether individually selected music can induce mood and maintain moods during a simulated drive. In addition, effects of positive, negative, and no music on driving behaviour and physiological measures were assessed for normal and high cognitive demanding rides. Subjective mood ratings indicated that music successfully maintained mood while driving. Narrow lane width drives increased task demand as shown in effort ratings and increased swerving. Furthermore, respiration rate was lower during music listening compared to rides without music, while no effects of music were found on heart rate. Overall, the current study demonstrates that music listening in car influences the experienced mood while driving, which in turn can impact driving behaviour. PRACTITIONERS SUMMARY: Even though it is a popular activity, little is known about the impact of music while driving on physiological state and performance. We examined whether music can induce moods during high and low simulated drives. The current study demonstrates that in car music listening influences mood which in turn can impact driving behaviour. The current study shows that listening to music can positively impact mood while driving, which can be used to affect state and safe behaviour. Additionally, driving performance in high demand situations is not negatively affected by music.     

Spatial frequencies in aesthetic website evaluations--explaining how ultra-rapid evaluations are formed

This study investigates how aesthetic website evaluations, especially those formed after very brief presentations, depend on visual information that is encoded in low- or high-spatial frequencies. A total of 92 participants took part in the experiment. The study used a 3 × 3 mixed design in which presentation time (50, 500 and 10000 ms) and spatial filtering (low-pass filtered, high-pass filtered and unfiltered stimuli) were manipulated. First, we replicate prior results from online studies of high- and low-spatial frequencies. Second, we confirm a prediction from neurocognitive models that only low-spatial frequencies are relevant to aesthetic judgements in ultra-rapid presentation modes. Third, we demonstrate that stimulus repetitions lead to an overestimation of the importance of ultra-rapid stimulus presentations. Taken together, our results highlight the utility of neurocognitive models of visual processing to explain the rapid aesthetic evaluation of websites. PRACTITIONER SUMMARY: Using neurocognitive models we present an approach to explain how aesthetic impressions are formed. We show that ultra-rapid judgements are connected with low- but not with high-spatial frequencies, which are neurologically processed in different visual pathways. Furthermore we identify possible methodological problems in previous studies of ultra-rapid website perception.     

Activity-rest schedules in physically demanding work and the variation of responses with age

Workers in physically demanding occupations require work breaks to recover from exertion. In a laboratory setting, we investigated the impact of ergometer cycling for 7 h in two conditions with an identical total break time but with two different activity-rest schedules. We hypothesised that more frequent but shorter breaks lead to less psychophysical strain and its effects than do less frequent but longer breaks, particularly for older workers. Twenty-nine participants representing three different age groups were tested in both conditions. Heart rate, perceived exertion/tension and feelings of fatigue were assessed and used as dependent variables. Results indicate no general activity-rest differences as well as no age-related differences of break effects under the condition of subjectively equal straining load. However, heart rate was found to be lower at some measurement points in the frequent-short-break condition and perceived exertion was lower in the infrequent-long-break condition. PRACTITIONER SUMMARY: Design of activity-rest schedules in physically demanding occupations is a key issue in the prevention of strain and hence of interest to ergonomists. Our study suggests that breaks during physically demanding work have the same effect if they are frequent and short or infrequent and long, regardless of age.     

如何加强和改进离退休人员的思想政治工作

中国已经进入了老龄化社会,退休人员成为建设和谐社会的一支重要力量,离退休人员的思想状况如何已引起社会高度重视。本文结合工作实际情况,认真探讨分析离退休人员的思想现状,建议当前应从以下几方面切实加强和改进离退休人员的思想政治工作：一是加强退休党支部建设,为加强离退休人员思想政治工作提供组织保障;二是进一步改善退休工作部门的服务管理工作,为做好离退休人员思想政治工作提供职能保障;三是掌控离退休人员思想动态,加强和改进思想政治工作的方法;四是注重落实并提高退休人员的生活待遇,为加强离退休人员思想政治教育打下良好工作基础;五是积极开展健康有益的文体活动,为加强思想政治工作提供有效载体。     

基层思想政治工作如何讲求规律性、针对性和创造性

基层思想政治工作必须结合生产活动的规律和特点,把握好规律性、针对性,注重创造性和时效性。做好基层思想政治工作要做到善于观察、分析、梳理,将工作时间和内容延伸到职工群众的日常工作和生活中;要创新工作内容、工作方法、工作机制,做到规范化、制度化和科学化。     

对改制企业党建思想政治工作的思考

调研认为,江汉油田供应处托管的改制企业党建思想政治工作存在着组织结构不合理、部分党员党性意识不强、基层党组织工作能力较弱、员工思想不稳定等问题,这也是油田改制企业普遍存在的问题。要解决好这些问题,一应提高认识,加强职工思想政治工作;二应加强指导,健全组织机构;三应改进和加强服务,提高服务水平和服务质量,切实为各改制企业解决好各类具体问题。