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Despite improvements in account security, compromise re- mains widespread and damaging, especially when the attacker has close physical or social proximity to the victim (e.g., interpersonal abuse settings). To help users identify unauthorized access, web services provide account security interfaces (ASIs): notifications and logs that provide information to help infer adversarial compromise. We present the largest measurement study of ASIs to date, evaluating 100 popular services. Our study highlights an unsatisfying status quo: 29 services provided users with no way to distinguish account accesses. After categorizing ASIs using a new typology, we show that services were inconsistent in the types they deployed. Further, ASIs were often incomplete and confusing, even for expert researchers. Finally, of 61 services that offered an ASI to convey device or location descriptions, 41 (67.2%) were vulnerable to spoofing attacks that successfully obfuscate the source of the access. Based on these findings, we present six principles for improving future ASI deployments. 

Abstract Lifetimes of excited states in$$^{162}$$ $_{}^{162}$Dy were measured using the (n,n’$$\gamma $$ $\gamma$) reaction with the Doppler-Shift Attenuation Method (DSAM) at the University of Kentucky’s Accelerator Laboratory. A total of eighteen level lifetimes were obtained, including eleven negative-parity states, seven of which are new. These measurements significantly expand the experimental database of transition probabilities for negative-parity bands in the well-deformed rare earth region of nuclei. The extracted B(E1) and B(E2) values reveal enhanced interband E1 ($$10^{-3}$$ ${10}^{-3}$or$$10^{-4}$$ ${10}^{-4}$) W.u. and E2 strengths (several W.u.) between negative- and positive parity bands, particularly for the KEquation missing<#comment/>bands decaying to the the K$$^{\pi }=2^+_{\gamma }$$ $_{}^{\pi }=2_{\gamma }^{+}$band, consistent with signatures of octupole-quadrupole coupling. In contrast, the K$$^{\pi }=0^-_1$$ $_{}^{\pi }=0_1^{-}$and K$$^{\pi }=1^-_3$$ $_{}^{\pi }=1_3^{-}$bands, which exhibit strong E1 transitions to the ground state band, are indicative of octupole-vibrational excitations built on the deformed ground state. Comparison of transition rates with Alaga rules supports this interpretation and distinguishes collective excitations from likely quasi-particle states. These new results establish$$^{162}$$ $_{}^{162}$Dy as the most extensively characterized rare-earth nucleus for negative parity lifetimes and provide critical experimental benchmarks for theoretical models. 

In-context learning is a remarkable capability of transformers, referring to their ability to adapt to specific tasks based on a short history or context. Previous research has found that task-specific information is locally encoded within models, though their emergence and functionality remain unclear due to opaque pre-training processes. In this work, we investigate the formation of task vectors in a controlled setting, using models trained from scratch on synthetic datasets. Our findings confirm that task vectors naturally emerge under certain conditions, but the tasks may be relatively weakly and/or non-locally encoded within the model. To promote strong task vectors encoded at a prescribed location within the model, we propose an auxiliary training mechanism based on a task vector prompting loss (TVP-loss). This method eliminates the need to search for task-correlated encodings within the trained model and demonstrably improves robustness and generalization. 

Abstract The low-lying structure of the well-deformed nucleus$$^{158}$$ $_{}^{158}$Gd has been revisited to elucidate the nature of the low-lying states in$$^{158}$$ $_{}^{158}$Gd. Earlier (p, t) studies identified numerous 0$$^+$$ $_{}^{+}$states below 4.3 MeV, prompting questions about whether these states correspond to collective vibrations or shape coexistence. New and previously reported ($$n,n^\prime \gamma $$ $n,n^{\prime }\gamma$) measurements are combined, including$$\gamma $$ $\gamma$-$$\gamma $$ $\gamma$coincidences, excitation functions, and angular distributions, to extract lifetimes and transition probabilities for 44 excited states up to 2.7 MeV, including 32 previously unmeasured levels. Our results confirm or revise$$\gamma $$ $\gamma$-ray placements and provide detailed transition strengths, revealing both weakly collective and strongly enhanced B(E2) and B(E1) transition probabilities. In particular, a tentative 0$$^+$$ $_{}^{+}$state at 2437.8 keV exhibits a strong interband B(E2) transition, which may be a candidate for a possible two-phonon ($$\beta \beta $$ $\beta \beta$) excitation. Systematic comparisons with neighboring Gd isotopes, Hartree–Fock–Bogoliubov, and interacting-boson model predictions suggest that the first excited 0$$^+$$ $_{}^{+}$state in$$^{158}$$ $_{}^{158}$Gd is predicted to be a$$\beta $$ $\beta$-vibration, although it is weakly collective. We also present results for lifetimes and transition probabilities for a number of negative parity states, including$$\hbox {K}^{\pi }=0^-,1^-,2^-$$ ${\text{K}}^{\pi }=0^{-},1^{-},2^{-}$sequences, perhaps providing insight into octupole collectivity and the interplay between quadrupole and octupole vibrations in deformed nuclei. The systematic presence of low-lying negative-parity bands and their interband transition strengths suggest that$$^{158}$$ $_{}^{158}$Gd’s potential energy surface may support both quadrupole and octupole vibrational modes, in agreement with microscopic calculations [1–3].