From Oaxacan wood carvings to dessert kitchens in provincial France, Critical Craft presents thirteen ethnographies which examine what defines and makes 'craft' in a wide variety of practices from ...around the world.
Eukaryotic gene regulation involves a balance between packaging of the genome into nucleosomes and enabling access to regulatory proteins and RNA polymerase. Nucleosomes are integral components of ...gene regulation that restrict access to both regulatory sequences and the underlying template. Whereas canonical histones package the newly replicated genome, they can be replaced with histone variants that alter nucleosome structure, stability, dynamics, and, ultimately, DNA accessibility. Here we consider how histone variants and their interacting partners are involved in transcriptional regulation through the creation of unique chromatin states.
Nucleosomes are barriers to transcription in vitro; however, their effects on RNA polymerase in vivo are unknown. Here we describe a simple and general strategy to comprehensively map the positions ...of elongating and arrested RNA polymerase II (RNAPII) at nucleotide resolution. We find that the entry site of the first (+1) nucleosome is a barrier to RNAPII for essentially all genes, including those undergoing regulated pausing farther upstream. In contrast to the +1 nucleosome, gene body nucleosomes are low barriers and cause RNAPII stalling both at the entry site and near the dyad axis. The extent of the +1 nucleosome barrier correlates with nucleosome occupancy but anticorrelates with enrichment of histone variant H2A.Z. Importantly, depletion of H2A.Z from a nucleosome position results in a higher barrier to RNAPII. Our results suggest that nucleosomes present significant, context-specific barriers to RNAPII in vivo that can be tuned by the incorporation of H2A.Z.
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•A simple strategy that maps all forms of RNA polymerase at nucleotide resolution•Nucleosomes are barriers to transcription for virtually all active genes•Entry to the +1 nucleosome is a major barrier to transcription in vivo•H2A.Z reduces the height of the nucleosomal barrier to transcription
How RNA polymerase transcribes across nucleosomes in vivo is unclear. Weber et al. describe a strategy to map the position of RNA polymerase at single-nucleotide resolution. They show that nucleosomes present context-specific barriers to transcriptional elongation that are modulated by the incorporation of histone variant H2A.Z.
Structural rearrangements within single molecules occur on ultrafast time scales. Many aspects of molecular dynamics, such as the energy flow through excited states, have been studied using ...spectroscopic techniques, yet the goal to watch molecules evolve their geometrical structure in real time remains challenging. By mapping nuclear motions using femtosecond x-ray pulses, we have created real-space representations of the evolving dynamics during a well-known chemical reaction and show a series of time-sorted structural snapshots produced by ultrafast time-resolved hard x-ray scattering. A computational analysis optimally matches the series of scattering patterns produced by the x rays to a multitude of potential reaction paths. In so doing, we have made a critical step toward the goal of viewing chemical reactions on femtosecond time scales, opening a new direction in studies of ultrafast chemical reactions in the gas phase.
As quantum coherence times of superconducting circuits have increased from nanoseconds to hundreds of microseconds, they are currently one of the leading platforms for quantum information processing. ...However, coherence needs to further improve by orders of magnitude to reduce the prohibitive hardware overhead of current error correction schemes. Reaching this goal hinges on reducing the density of broken Cooper pairs, so-called quasiparticles. Here, we show that environmental radioactivity is a significant source of nonequilibrium quasiparticles. Moreover, ionizing radiation introduces time-correlated quasiparticle bursts in resonators on the same chip, further complicating quantum error correction. Operating in a deep-underground lead-shielded cryostat decreases the quasiparticle burst rate by a factor thirty and reduces dissipation up to a factor four, showcasing the importance of radiation abatement in future solid-state quantum hardware.
State capitalism is experiencing a revival as a term to capture the current capitalist constellations and departures from neoliberalism. Unlike, neoliberalism, however, the term state capitalism has ...a long history reaching back to the age of imperialism in the late 19th century. Although state capitalism has been used as a prerogative term by Marxists, liberals, and neoliberals alike, it has served as a programmatic label for developmentalist and neomercantilist projects in reaction to imperialism in the periphery. This paper argues that we need to bring the intellectual history of state capitalism into the ‘new state capitalism’ debate. China has played a major role in the revival of state capitalism in the social sciences, but the long history of China's engagement with state capitalism as a concept and program dating back to the late Qing reformers has been overlooked for the most part. State capitalism is by no means new to China, from Liang Qichao, Sun Yatsen, and Mao Zedong to Deng Xiaoping, the idea that China had to create a modern nation-state and industrial capitalism in the name of economic progress and to get ahead in the global competition is a recurring theme. What is new is that for the first time, the ambition to use state capitalism as a means to catch up with the West is bearing fruits in ways that could undermine the predominance of Western economies.
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