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We present a new coarse-grained model and molecular simulation study of polysulfamide, a new class of polymer that could be a sustainable alternative to commodity polymers like polyurea. 

Abstract A surgeon peers downward into a body cavity when operating. Holding this position for hours across weeks, months, and years may lead to neck pain and musculoskeletal disorders. We were inspired by ungulates such as giraffes and horses, which use dorsal‐ventral flexion to graze for 9–14 h per day without perceivable neck pain. Ungulates evolved a strong nuchal ligament that relieves neck muscles by stretching to support some of the weight of the head during grazing or running. In contrast, humans evolved an upright posture, and like many primates, have a reduced nuchal ligament. The goal of this study is to use the nuchal ligament as inspiration for a neck brace that passively supports the weight of the head while still permitting lateral flexion, ventral‐dorsal flexion, and rotation. We assembled a prototype using an elastic band, headband, and back posture corrector. Our device augments the human nuchal ligament by using a stiff material and greater mechanical advantage. By our calculations, flexing the head ventrally 40 degrees when wearing the brace reduces the torque applied by neck muscles by 21%. Our device is a proof‐of‐concept that a bioinspired device can offload neck muscular tension and prevent injury. 

Abstract We introduce and study a genuine equivariant refinement of the Tate construction associated to an extension of a finite group by a compact Lie group , which we call the parameterized Tate construction . Our main theorem establishes the coincidence of three conceptually distinct approaches to its construction when is also finite: one via recollement theory for the ‐free ‐family, another via parameterized ambidexterity for ‐local systems, and the last via parameterized assembly maps. We also show that uniquely admits the structure of a lax ‐symmetric monoidal functor, thereby refining a theorem of Nikolaus and Scholze. Along the way, we apply a theorem of the second author to reprove a result of Ayala–Mazel‐Gee–Rozenblyum on reconstructing a genuine ‐spectrum from its geometric fixed points; our method of proof further yields a formula for the geometric fixed points of an ‐complete ‐spectrum for any ‐family .