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Piebaldism is a genetic pigmentation disorder, which is caused by absence of melanocytes in parts of the skin and/or hair follicles, with eyes and claws normally pigmented. The occurrence of piebaldism in natural populations is rare and the effects on fitness are still unknown. This article reports the first case of pigmentation disorders in the Fringe-lipped Bat Trachops cirrhosus (Spix, 1823) (Chiroptera: Phyllostomidae) caught in Barra do Triunfo, city of João Neiva, northeastern state of Espírito Santo, southeast Brazil.

• Asynchronous NOMA with time offsets further enhances the performance of NOMA. • Asynchronous NOMA with nonlinear waveforms brings power efficiency benefits. • Two transceivers based on the maximum likelihood criterion are developed. • The properties of Hermitian- and banded-Toeplitz matrices are fully exploited. • The performance in various perspectives is investigated by numerical simulation. The time offset is intentionally introduced into non-orthogonal multiple access (NOMA) to decrease inter-user interference and enhance performance. Recently, minimum shift keying type (MSK-type) signals suitable for power-efficient nonlinear amplifiers have been considered into the uplink asynchronous NOMA (ANOMA), but it is only for the capacity analysis. In this paper, the transceiver design for an uplink ANOMA using MSK-type signals is our concern. Following the maximum likelihood (ML) criterion under successive interference cancellation (SIC), we first propose a Viterbi algorithm (VA)-based detector. By the eigenvalue decomposition (ED) of Hermitian-Toeplitz matrices, an ED-based transceiver scheme is also given. Further, considering the asymptotic behavior of banded-Toeplitz matrices and the limitations of SIC-based transceivers, we propose a DFT matrix diagonalization (DFTD)-based transceiver scheme for joint ML (JML) detection. Finally, the complexity analysis of several detectors is provided. Numerical results reveal that the maximum sum throughput can be achieved by setting half the bit interval, and the time offset can bring a performance gain of 4 dB or 7.5 dB for SIC-based transceivers and 8 dB for JML-based transceivers. The relationship between bit-error-rate (BER) performance and different channel differences, and modulation formats is also shown by simulation. [ABSTRACT FROM AUTHOR]

In this letter, we propose a novel symbol-asynchronous non-orthogonal multiple access (ANOMA) scheme for downlink transmissions. First, ANOMA introduces an artificial symbol-offset between packets destined for different user equipment (UE) in order to reduce their mutual interference. Second, ANOMA adopts a pre-coding at the base station and a whitening-and-decomposing (WD) detection scheme at the receiving UE to simplify signal detection. With these two novel techniques, ANOMA can significantly enlarge the achievable rate region of the traditional non-orthogonal multiple access (NOMA). Moreover, the impact of pulse shape and symbol offset on the performance of ANOMA scheme are investigated in both Gaussian and Rayleigh block-fading channels. The numerical results show that ANOMA with precoding and WD detection outperforms asynchronous NOMA with successive interference cancellation detection, both outperform synchronous NOMA. [ABSTRACT FROM PUBLISHER]