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651.
This investigation was conducted to determine the effects of a massaging lumbar support system on low back muscle activity. The apparatus included a luxury-level automobile seat, six 10-mm diameter bipolar surface electrodes, an amplifier, an analog-to-digital conversion board, data acquisition software, and a personal computer. Six experimental conditions, each involving a variation of massage time, were considered. The dependent variable was the change in the root mean square variation of the EMG signal. One minute of lumbar massage every 5 min was found to have a beneficial effect on low back muscle activity (as compared to no massage). This may prove to be an extremely important result in the quest to combat low back pain attributable to automobile seating.  相似文献   
652.
Carpal Tunnel Syndrome (CTS) is an important problem among computer professionals. Hence the prevalence of CTS among computer professionals and risk factors were studied. 648 subjects were selected from 4,276 computer professionals from 21 companies with a simple random sampling method. CTS was diagnosed based on clinical features.

The prevalence of CTS was found to be 13.1% (95% CI 10.5–15.7%). Subjects with over 8 years of computer work, over 12 hrs of work per day and system administrators were at a higher risk for CTS (OR 3.3, 4.9 and 2.5 respectively). Flexed or extended hand position had higher risk for CTS.

Higher risk for CTS was found with higher exposure to computer work. Ergonomic considerations are important in facilitating proper positioning of hand while working with a computer. Further studies on CTS risk factors among computer professionals are essential for planning prevention.  相似文献   
653.
The present study examines the natural radioactivity in some sedimentary rocks and their associated environmental impacts at Wadi Naseib area. Exposure rate (ER), dose rate (DR), radium equivalent activity (Ra(eq)), external hazard index (H(ex)), internal hazard index (H(in)) and radioactivity level index (I(gamma)) were calculated. Wadi Naseib area is covered with sedimentary rocks of early to late Paleozoic age. These rocks are classified into two types: mineralized and non-mineralized sediments. The radiometric investigations revealed that uranium and thorium contents reached up to 710 and 520 ppm, respectively, in the mineralized rocks. This was attributed to the presence of some secondary uranium minerals. All sediments had low values of eTh and K content. The exposure and dose rates exceeded public permissible values in the mineralized sediments. Exposure and dose rates were within the safety range for workers and the public in the non-mineralized sediments. The expected environmental impacts may be low due to the limited occurrence of U-mineralization and corresponding areas for radiation exposure. Some precautions and recommendations were suggested to avoid any possible environmental impacts from areas and/or raw materials of high intensity of natural radiation sources.  相似文献   
654.
Environmental Chemistry Letters - Actual agricultural practices produce about 998 million tonnes of agricultural waste per year. Therefore, converting lignocellulosic wastes into energy, chemicals,...  相似文献   
655.
Environmental Science and Pollution Research - In this study, mercaptosuccinic acid capped CdSe nanocrystals were successfully synthesized and used as photocatalyst for the effective removal of...  相似文献   
656.
Environmental Science and Pollution Research - Coliform mastitis is a worldwide serious disease of the mammary gland. Curcumin is a pleiotropic polyphenol obtained from turmeric, but it is...  相似文献   
657.
Environmental Science and Pollution Research - Present study was conducted to check the heavy metal content in wheat treated with municipal solid waste, Although municipal solid waste was enriched...  相似文献   
658.
Environmental Science and Pollution Research - This work aims to investigate the adsorption performance of orange G (OG) dye from aqueous solutions employing PANI@sawdust biocomposite enrobed by...  相似文献   
659.
Environmental Science and Pollution Research - The heterogeneous photocatalysis is known to provide significant degradation and mineralization of emerging contaminants including antibiotics. For...  相似文献   
660.
Environmental Science and Pollution Research - The objective of the current study is to investigate the performance of the inclined solar panel basin still (ISPBS) incorporated with a spiral tube...  相似文献   
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