An Evaluation of the NIOSH Lifting Equation: A Psychophysical and Biomechanical Investigation
Using the results of psychophysical and biomechanical experiments, NIOSH (National Institute for Occupational Safety and Health) Recommended Weight Limit (RWL), the Lifting Index (LI), the form of the asymmetry multiplier, and the criterion for compression force were investigated. Analysis of the results indicated a significant difference between the NIOSH RWL and the reported Maximum Acceptable Weight of Lift (MAWL). Contrary to the NIOSH lifting equation, the form of the asymmetry multiplier was found to be non-linear. The overall average of peak compression force on the L5/S1 was 3685 N. Fifty-eight percent of all compression forces reported in the biomechanical experiment were found to exceed the suggested 3400 N set by NIOSH guidelines. These results support previous research findings on the validity of NIOSH guidelines.
Changes in Back Compressive Force When Measuring Maximum Acceptable Weight of Lift in Iranian Male Students
Background: Low back pain caused by work, ranked the second after cardiovascular diseases, are among the most common reasons of patients’ referral to the physicians in Iran. This study aimed to determine the changes in back compressive force when measuring maximum acceptable weight of lift in Iranian male students. Methods: This experimental study was conducted in 2015 on 15 young male students were recruited from Tehran University of Medical Science. Each participant performed 18 different lifting tasks involving three lifting frequencies, with three lifting heights, and two box sizes. Each set of experiments was conducted during the 20 min work period using free-style lifting technique. The back compressive force evaluated with hand-calculation back compressive force method. Finally, Pearson correlation test, analysis of variance (ANOVA) and t-test were used for data analysis. Results: The mean of back compressive force (BCF) for the small and large boxes at a frequency of 1lift/min at heights of F - K height, were 1001.02 (±86.74), 1210.57 (±93.77) Ib, respectively. There was a significant difference between mean BCF in terms of frequencies of lifts (P=0.02). The result revealed significant difference between frequencies of 1 lift/min and 6.67 lift/min (P=0.01). There was a significant difference between mean BCF in terms of the sizes of the two boxes (P=0.001). There was a significant relationship between the BCF and maximum acceptable weight of lift in all test conditions (P=0.001). Conclusion: BCF is affected by box size, lifting frequency and weight of load.
Nietzsche's Task: An Interpretation of Beyond Good and Evil
When Nictzsche published Beyond Good and Evil in 1886, he told a friend that it was a book that would not be read properly until "around the year 2000". Now Laurence Lampert sets out to fulfill this prophecy by providing a section by section interpretation of this philosophical masterpiece that emphasises its unity and depth as a comprehensive new doctrine on nature and humanity. According to Lampert, Nietzsche begins with a critique of philosophy that is ultimately affirmative, because it shows how philosophy can arrive at a defensible ontological account of the way of all beings. Nietzsche next argues that a new post-Christian religion can arise out of the affirmation of the world disclosed to philosophy. Then, turning to the implications of the new ontology for morality and politics, Nietzsche argues that these can be reconstituted on the fundamental insights of the new philosophy. Nietzsche's comprehensive depiction of this anti-Platonic philosophy ends with a chapter on nobility, in which he contends that what can now be publicly celebrated as noble in our species are its highest achievements of mind and spirit.