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Structure-Aware private set intersection (sa-PSI) is a variant of PSI where Alice’s input set A has some publicly known structure, Bob’s input B is an unstructured set of points, and Alice learns the intersection A ∩ B. sa-PSI was recently introduced by Garimella et al. (Crypto 2022), who described a semi-honest protocol with communication that scales with the description size of Alice’s set, instead of its cardinality. In this paper, we present the first sa-PSI protocol secure against malicious adversaries. sa-PSI protocols are built from function secret sharing (FSS) schemes, and the main challenge in our work is ensuring that multiple FSS sharings encode the same structured set. We do so using a cut-and-choose approach. In order to make FSS compatible with cut-and-choose, we introduce a new variant of function secret sharing, called derandomizable FSS (dFSS). We show how to construct dFSS for union of geometric balls, leading to a malicious-secure sa-PSI protocol where Alice’s input is a union of balls. We also improve prior FSS constructions, giving asymptotic improvements to semi-honest sa-PSI. 

Commitment to cell division at the end of G1 phase, termed Start in the budding yeast Saccharomyces cerevisiae , is strongly influenced by nutrient availability. To identify new dominant activators of Start that might operate under different nutrient conditions, we screened a genome-wide ORF overexpression library for genes that bypass a Start arrest caused by absence of the G1 cyclin Cln3 and the transcriptional activator Bck2. We recovered a hypothetical gene YLR053c , renamed NRS1 for Nitrogen-Responsive Start regulator 1, which encodes a poorly characterized 108 amino acid microprotein. Endogenous Nrs1 was nuclear-localized, restricted to poor nitrogen conditions, induced upon TORC1 inhibition, and cell cycle-regulated with a peak at Start. NRS1 interacted genetically with SWI4 and SWI6 , which encode subunits of the main G1/S transcription factor complex SBF. Correspondingly, Nrs1 physically interacted with Swi4 and Swi6 and was localized to G1/S promoter DNA. Nrs1 exhibited inherent transactivation activity, and fusion of Nrs1 to the SBF inhibitor Whi5 was sufficient to suppress other Start defects. Nrs1 appears to be a recently evolved microprotein that rewires the G1/S transcriptional machinery under poor nitrogen conditions. 

Abstract Spin waves, quantized as magnons, have low energy loss and magnetic damping, which are critical for devices based on spin‐wave propagation needed for information processing devices. The organic‐based magnet [V(TCNE)_x; TCNE = tetracyanoethylene;x≈ 2] has shown an extremely low magnetic damping comparable to, for example, yttrium iron garnet (YIG). The excitation, detection, and utilization of coherent and non‐coherent spin waves on various modes in V(TCNE)_xis demonstrated and show that the angular momentum carried by microwave‐excited coherent spin waves in a V(TCNE)_xfilm can be transferred into an adjacent Pt layer via spin pumping and detected using the inverse spin Hall effect. The spin pumping efficiency can be tuned by choosing different excited spin wave modes in the V(TCNE)_xfilm. In addition, it is shown that non‐coherent spin waves in a V(TCNE)_xfilm, excited thermally via the spin Seebeck effect, can also be used as spin pumping source that generates an electrical signal in Pt with a sign change in accordance with the magnetization switching of the V(TCNE)_x. Combining coherent and non‐coherent spin wave detection, the spin pumping efficiency can be thermally controlled, and new insight is gained for the spintronic applications of spin wave modes in organic‐based magnets.