Abstract: A semiconductor device comprising a nominally or exactly or equivalent orientation silicon substrate on which is grown directly a <100 nm thick nucleation layer (NL) of a III-V compound semiconductor, other than GaP, followed by a buffer layer of the same compound, formed directly on the NL, optionally followed by further III-V semiconductor layers, followed by at least one layer containing III-V compound semiconductor quantum dots, optionally followed by further III-V semiconductor layers. The NL reduces the formation and propagation of defects from the interface with the silicon, and the resilience of quantum dot structures to dislocations enables lasers and other semiconductor devices of improved performance to be realized by direct epitaxy on nominally or exactly or equivalent orientation silicon.

Abstract: A semiconductor light-emitting element includes: a lower clad layer 12 that is provided on a substrate 10; an active layer 20 that is provided on the lower clad layer 12 and includes a quantum well layer 24 and a plurality of quantum dots 28 sandwiching a second barrier layer 22b together with the quantum well layer 24; and an upper clad layer 14 that is provided on the active layer 20, wherein a distance D between the quantum well layer 24 and the plurality of quantum dots 28 is smaller than an average of distances X between centers of the plurality of quantum dots 28.

Abstract: A semiconductor light-emitting element includes: a lower clad layer 12 that is provided on a substrate 10; an active layer 20 that is provided on the lower clad layer 12 and includes a quantum well layer 24 and a plurality of quantum dots 28 sandwiching a second barrier layer 22b together with the quantum well layer 24; and an upper clad layer 14 that is provided on the active layer 20, wherein a distance D between the quantum well layer 24 and the plurality of quantum dots 28 is smaller than an average of distances X between centers of the plurality of quantum dots 28.

Abstract: Methods for preventing, ameliorating, or reducing dermatological signs of aging are provided which employ active agents, other than a retinoid, that stimulate thymosin beta-4 expression in the skin. Also provided are methods for screening for substances which stimulate thymosin beta-4 expression levels and the methods of using active agents identified by the screening protocol in the treatment of skin.

Abstract: Methods for preventing, ameliorating, or reducing dermatological signs of aging are provided which employ active agents, other than a retinoid, that stimulate thymosin beta-4 expression in the skin. Also provided are methods for screening for substances which stimulate thymosin beta-4 expression levels and the methods of using active agents identified by the screening protocol in the treatment of skin.