The absorption characteristics of some UV and blue-light-filtering IOLs resembled those of the crystalline lens, but some differed. Long-term clinical trials should be performed to determine how blue-blocking IOLs affect the risk for progression of age-related macular degeneration.

Despite numerous studies of selection on position and number of spectral vision bands, explanations to the function of narrow spectral bands are lacking. We investigate dragonflies (Odonata), which have the narrowest spectral bands reported, in order to investigate what features these narrow spectral bands may be used to perceive. We address whether it is likely that narrow red bands can be used to identify conspecifics by the optical signature from wing interference patterns (WIPs). We investigate the optical signatures of Odonata wings using hyperspectral imaging, laser profiling, ellipsometry, polarimetric modulation spectroscopy, and laser radar experiments. Based on results, we estimate the prospects for Odonata perception of WIPs to identify conspecifics in the spectral, spatial, intensity, polarization, angular, and temporal domains. We find six lines of evidence consistent with an ability to perceive WIPs. First, the wing membrane thickness of the studied Odonata is 2.3 μm, coinciding with the maximal thickness perceivable by the reported bandwidth. Second, flat wings imply that WIPs persist from whole wings, which can be seen at a distance. Third, WIPs constitute a major brightness in the visual environment only second after the solar disk. Fourth, WIPs exhibit high degree of polarization and polarization vision coincides with frontal narrow red bands in Odonata. Fifth, the angular light incidence on the Odonata composite eye provides all prerequisites for direct assessment of the refractive index which is associated with age. Sixth, WIPs from conspecifics in flight make a significant contribution even to the fundamental wingbeat frequency within the flicker fusion bandwidth of Odonata vision. We conclude that it is likely that WIPs can be perceived by the narrow red bands found in some Odonata species and propose future behavioral and electrophysiological tests of this hypothesis.

Recently, a new power-split hybrid electric vehicle drivetrain has been developed by the Corporate Research and Development Department of the Robert Bosch company and two research cars equipped with this powertrain have been built. Owing to the loop-like arrangement of the shafts in the newly developed Dual-E Transmission, circulating power can arise in this system. In general, circulating power leads to high mesh losses because the power transmitted by some components becomes greater than the input or output power. This paper presents a detailed analysis of circulating power in the Dual-E Transmission. It is shown that the solution of the energy balance equations is given by a linear combination of four basic power flows. The factors in this linear combination, however, cannot be uniquely determined from the energy balance alone. Therefore, the transmission kinematics and dynamics are dealt with in detail. Subsequently, a mathematical description as well as a graphical representation of the circulating-power-free operating range are derived. This elaboration provides a solid basis for the development of a fuel-efficient operating strategy.

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Recently, a new power split hybrid electric vehicle drive train has been developed by the Corporate Research and Development Department of the Robert Bosch Company. The new drive train differs from a conventional one in many respects. In this paper we investigate how these differences affect the vibrational behavior of the drive line. With the aid of a linear mechanical model, a modal analysis is performed and the effect of the control of the drive train on the eigenvibrations is studied. The analysis reveals, for example, a shuffle behavior, which can also be observed in vehicles with conventional drive train. The constant of the I part of the controller influences the vibrational behavior in quite a complex way. Starting from zero and steadily increasing the control parameter, one of the modes undergoes three metamorphoses. On the basis of this fundamental understanding, two strategies for the optimization of the drive line vibrational behavior are proposed. Furthermore, the simple mechanical model is refined with regard to various aspects. For example, tire slip is taken into account and a two-track model capturing asymmetric vibrations of the two axle shafts or wheels is considered.