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We present gradient corrected density function theory calculations on the adsorption and thermally activated diffusion pathways of hydrogen on the {111} surfaces of Ni, Pd, and Pt. We find that the variation of the adsorption energy as a function of adsorption site shows considerable differences between the three metals. For Ni and Pd, the adsorption energies vary as a function of hydrogen coordination with the 3-fold hollow sites the most stable and the 1-fold atop site considerably less stable. On Pt the adsorption energies for all the sites are similar indicating that diffusion across the surface will be faster on Pt than on Ni or Pd. The activation energies for diffusion have been calculated with that for Pt (2−3 kJ mol-1) considerably smaller than for Ni or Pd (13 kJ mol-1). The calculated adsorption and activation energies are in good agreement with experimental investigations of the structure, energetics, and diffusion properties.

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Physical assessment of 146 female workers in highly repetitive jobs found 54% to have evidence of musculoskeletal disorders in the upper limb that are potentially work-related. Many workers had multiple problems, and many were affected bilaterally (33% of workers). Muscle pain and tenderness was the largest problem, both in the neck/shoulder area (31%) as expected and in the forearm/hand musculature (23%), a previously unreported site. Most forearm muscle problems were found on the extensor side. Carpal tunnel syndrome was the most common form of neuritis with 16 people affected (7 people affected bilaterally). De Quervain's tenosynovitis and wrist flexor tendinitis were the most commonly found tendon disorders in the distal forearm (12 people affected for each diagnosis). The results suggest that exposure should be measured bilaterally. They also suggest that muscle tissue is highly vulnerable to overuse. Stressors that affect muscle tissue, such as static loading, should be studied in the forearm as well as in the shoulder.