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1. The Lyman Continuum Escape Survey: Connecting Time-dependent [O iii] and [O ii] Line Emission with Lyman Continuum Escape Fraction in Simulations of Galaxy Formation

   https://doi.org/10.3847/2041-8213/abbd8e  

   Barrow, Kirk S. ; Robertson, Brant E. ; Ellis, Richard S. ; Nakajima, Kimihiko ; Saxena, Aayush ; Stark, Daniel P. ; Tang, Mengtao ( October 2020 , The Astrophysical Journal)
2. The synchrony of production and escape: half the bright Lyα emitters at z  ≈ 2 have Lyman continuum escape fractions ≈50

   https://doi.org/10.1093/mnras/stab3601  

   Naidu, Rohan P. ; Matthee, Jorryt ; Oesch, Pascal A. ; Conroy, Charlie ; Sobral, David ; Pezzulli, Gabriele ; Hayes, Matthew ; Erb, Dawn ; Amorín, Ricardo ; Gronke, Max ; et al ( December 2021 , Monthly Notices of the Royal Astronomical Society)

   The ionizing photon escape fraction [Lyman continuum (LyC) fesc] of star-forming galaxies is the single greatest unknown in the reionization budget. Stochastic sightline effects prohibit the direct separation of LyC leakers from non-leakers at significant redshifts. Here we circumvent this uncertainty by inferring fesc using resolved (R > 4000) Lyman α (Lyα) profiles from the X-SHOOTER Lyα survey at z = 2 (XLS-z2). With empirically motivated criteria, we use Lyα profiles to select leakers ($f_{\mathrm{ esc}} > 20{{\ \rm per\ cent}}$) and non-leakers ($f_{\mathrm{ esc}} < 5{{\ \rm per\ cent}}$) from a representative sample of >0.2L* Lyman α emitters (LAEs). We use median stacked spectra of these subsets over λrest ≈ 1000–8000 Å to investigate the conditions for LyC fesc. Our stacks show similar mass, metallicity, MUV, and βUV. We find the following differences between leakers versus non-leakers: (i) strong nebular C iv and He ii emission versus non-detections; (ii) [O iii]/[O ii] ≈ 8.5 versus ≈3; (iii) Hα/Hβ indicating no dust versus E(B − V) ≈ 0.3; (iv) Mg ii emission close to the systemic velocity versus redshifted, optically thick Mg ii; and (v) Lyα fesc of ${\approx} 50{{\ \rm per\ cent}}$ versus ${\approx} 10{{\ \rm per\ cent}}$. The extreme equivalent widths (EWs) in leakers ([O iii]+$\mathrm{ H}\beta \approx 1100$ Å rest frame)more »constrain the characteristic time-scale of LyC escape to ≈3–10 Myr bursts when short-lived stars with the hardest ionizing spectra shine. The defining traits of leakers – extremely ionizing stellar populations, low column densities, a dust-free, high-ionization state interstellar medium (ISM) – occur simultaneously in the $f_{\rm esc} > 20{{\ \rm per\ cent}}$ stack, suggesting they are causally connected, and motivating why indicators like [O iii]/[O ii] may suffice to constrain fesc at z > 6 with the James Webb Space Telescope (JWST). The leakers comprise half of our sample, have a median LyC$f_{\rm esc} \approx 50{{\ \rm per\ cent}}$ (conservative range: $20\!-\!55{{\ \rm per\ cent}}$), and an ionizing production efficiency $\log ({\xi _{\rm {ion}}/\rm {Hz\ erg^{-1}}})\approx 25.9$ (conservative range: 25.7–25.9). These results show LAEs – the type of galaxies rare at z ≈ 2, but that become the norm at higher redshift – are highly efficient ionizers, with extreme ξion and prolific fesc occurring in sync.

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3. Vaccine-escape and fast-growing mutations in the United Kingdom, the United States, Singapore, Spain, India, and other COVID-19-devastated countries

   https://doi.org/10.1016/j.ygeno.2021.05.006  

   Wang, Rui ; Chen, Jiahui ; Gao, Kaifu ; Wei, Guo-Wei ( July 2021 , Genomics)
4. Escape from natural enemies depends on the enemies, the invader, and competition

   https://doi.org/10.1002/ece3.6737  

   Lucero, Jacob E. ; Arab, Nafiseh Mahdavi ; Meyer, Sebastian T. ; Pal, Robert W. ; Fletcher, Rebecca A. ; Nagy, David U. ; Callaway, Ragan M. ; Weisser, Wolfgang W. ( October 2020 , Ecology and Evolution)
5. Influencing Human Escape Maneuvers With Perceptual Cues in the Presence of a Visual Task

   https://doi.org/10.1109/THMS.2021.3108962  

   Bajpai, Aakash ; Feigh, Karen M. ; Mazumdar, Anirban ; Young, Aaron J. ( January 2021 , IEEE Transactions on Human-Machine Systems)