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Most research studies on deep learning (DL) applied to the physical layer of wireless communication do not put forward the critical role of the accuracy-generalization trade-off in developing and evaluating practical algorithms. To highlight the disadvantage of this common practice, we revisit a data decoding example from one of the first papers introducing DL-based end-to-end wireless communication systems to the research community and promoting the use of artificial intelligence (AI)/DL for the wireless physical layer. We then put forward two key trade-offs in designing DL models for communication, namely, accuracy versus generalization and compression versus latency. We discuss their relevance in the context of wireless communications use cases using emerging DL models, including large language models (LLMs). Finally, we summarize our proposed evaluation guidelines to enhance the research impact of DL on wireless communications. These guidelines are an attempt to reconcile the empirical nature of DL research with the rigorous requirement metrics of wireless communications systems. 

Peptoids belong to a class of sequence‐controlled polymers comprising ofN‐alkylglycine. This study focuses on using tandem mass spectrometry techniques to characterize the fragmentation patterns of a set of singly and doubly protonated peptoids consisting of one basic residue placed at different positions. The singly protonated peptoids fragment by producing predominately high‐abundant C‐terminal ions called Y‐ions and low‐abundant N‐terminal ions called B‐ions. Computational studies suggest that the proton affinity (PA) of the C‐terminal fragments is generally higher than that of the N‐terminal fragments, and the PA of the former increases as the fragments are elongated. The B‐ions are likely formed upon dissociating the proton‐activated amide bonds via an oxazolone structure, and the Y‐ions are produced subsequently by abstracting a proton from the newly formed B‐ions, which is energetically favored. The doubly protonated peptoids prefer to fragment closest to either the N‐ or the C‐terminus and produce corresponding B/Y‐ion pairs. The basic residue seems to dictate the preferred fragmentation site, which may be the result of minimizing the repulsion between the two charges. Water and terminal neutral losses are a facile process accompanying the peptoid fragmentation in both charge states. The patterns appear to be highly influenced by the location of the basic residue.