Catalogue Search | MBRL
Are you sure you want to remove the book from the shelf?
{{itemTitle}}
21,060
result(s) for
"Adam, R"
Sort by:
The Irreducible Subgroups of Exceptional Algebraic Groups
This paper is a contribution to the study of the subgroup structure of exceptional algebraic groups over algebraically closed fields
of arbitrary characteristic. Following Serre, a closed subgroup of a semisimple algebraic group
A result of Liebeck and Testerman shows that each irreducible connected subgroup
eBook
Towards real-world generalizability of a circuit for action-stopping
Two decades of cross-species neuroscience research on rapid action-stopping in the laboratory has provided motivation for an underlying prefrontal–basal ganglia circuit. Here we provide an update of key studies from the past few years. We conclude that this basic neural circuit is on increasingly firm ground, and we move on to consider whether the action-stopping function implemented by this circuit applies beyond the simple laboratory stop signal task. We advance through a series of studies of increasing ‘real-worldness’, starting with laboratory tests of stopping of speech, gait and bodily functions, and then going beyond the laboratory to consider neural recordings and stimulation during moments of control presumably required in everyday activities such as walking and driving. We end by asking whether stopping research has clinical relevance, focusing on movement disorders such as stuttering, tics and freezing of gait. Overall, we conclude there are hints that the prefrontal–basal ganglia action-stopping circuit that is engaged by the basic stop signal task is recruited in myriad scenarios; however, truly proving this for real-world scenarios requires a new generation of studies that will need to overcome substantial technical and inferential challenges.Many studies implicate a prefrontal–basal ganglia circuit in the control of action-stopping. Here, Ricci Hannah and Adam Aron provide an update of studies of this circuit, discuss its clinical relevance, and consider whether its action-stopping function applies in real-world scenarios, beyond the laboratory.
Journal Article
A quantum complexity lower bound from differential geometry
Differential geometry has long found applications in physics in general relativity and related areas. More recently, it was proposed by Nielsen that the tools of differential geometry, when applied to the unitary group, might be used to bound the complexity of quantum operations. The Bishop–Gromov bound—a cousin of the focusing lemmas used to prove the Penrose–Hawking black hole singularity theorems—is a differential geometry result that gives an upper bound on the rate of growth of the volume of geodesic balls in terms of the Ricci curvature. Here I apply the Bishop–Gromov bound to Nielsen’s complexity geometry to prove lower bounds on the quantum complexity of a typical unitary. For a broad class of models, the typical complexity is shown to be exponentially large in the number of qubits. This technique gives results that are tighter than all known lower bounds in the literature, as well as establishing lower bounds for a much broader class of complexity geometry metrics than has hitherto been bounded. This method thus realizes the original vision of Nielsen, which was to apply the tools of differential geometry to study quantum complexity.Quantum operations can be considered as points in a high-dimensional space in which distance reflects the similarity of two operations. Applying differential-geometric methods in this picture gives insights into the complexity of quantum systems.
Journal Article
Leisure and death : an anthropological tour of risk, death, and dying / edited by Adam Kaul, Jonathan Skinner
\"Interdisciplinary study of dark tourism that examines the relationship between leisure and death, specifically how leisure practice is used to meditate upon and mediate life. Grounded in international anthropological case studies, the authors theorize on the links between spaces of death and leisure\"--Provided by publisher.
Book
Structure of the nucleotide exchange factor eIF2B reveals mechanism of memory-enhancing molecule
In rodents, a druglike small molecule named ISRIB enhances cognition and reverses cognitive deficits after traumatic brain injury. ISRIB activates a protein complex called eIF2B that is required for the synthesis of new proteins. Tsai et al. report the visualization of eIF2B bound to ISRIB at near-atomic resolution by cryo–electron microscopy. Biochemical studies revealed that ISRIB is a “molecular staple” that promotes assembly of the fully active form of eIF2B. Zyryanova et al. report similar structures together with information on the binding of ISRIB analogs and their effects on protein translation. Science , this issue p. eaaq0939 , p. 1533 A drug-like inhibitor of the integrated stress response bridges tetrameric subcomplexes of eIF2B, assembling active holoenzyme. Regulation by the integrated stress response (ISR) converges on the phosphorylation of translation initiation factor eIF2 in response to a variety of stresses. Phosphorylation converts eIF2 from a substrate to a competitive inhibitor of its dedicated guanine nucleotide exchange factor, eIF2B, thereby inhibiting translation. ISRIB, a drug-like eIF2B activator, reverses the effects of eIF2 phosphorylation, and in rodents it enhances cognition and corrects cognitive deficits after brain injury. To determine its mechanism of action, we solved an atomic-resolution structure of ISRIB bound in a deep cleft within decameric human eIF2B by cryo–electron microscopy. Formation of fully active, decameric eIF2B holoenzyme depended on the assembly of two identical tetrameric subcomplexes, and ISRIB promoted this step by cross-bridging a central symmetry interface. Thus, regulation of eIF2B assembly emerges as a rheostat for eIF2B activity that tunes translation during the ISR and that can be further modulated by ISRIB.
Journal Article
Civil War wests : testing the limits of the United States
\"This volume unifies the concerns of Civil War and western history, revealing how Confederate secession created new and shifting borderlands. In the West, both Civil War battlefields and Civil War politics engaged a wider range of ethnic and racial distinctions, raising questions that would arise only later in places farther east. Likewise, the histories of occupation, reincorporation, and expanded citizenship during Reconstruction in the South have ignored the connections to previous as well as subsequent efforts in the West. The stories contained in this volume complicate our understanding of the paths from slavery to freedom for white as well as non-white Americans. By placing the histories of the American West and the Civil War and Reconstruction into one sustained conversation, this volume expands the limits of both by emphasizing how struggles over land, labor, sovereignty, and citizenship shaped the U.S. nation-state in this tumultuous era. This volume highlights significant moments and common concerns of this continuous conflict, as it stretched across the continent and throughout the nineteenth century\"--Provided by publisher.
Book
Near-zone symmetries of Kerr black holes
A
bstract
We study the near-zone symmetries of a massless scalar field on four-dimensional black hole backgrounds. We provide a geometric understanding that unifies various recently discovered symmetries as part of an SO(4
,
2) group. Of these, a subset are exact symmetries of the static sector and give rise to the ladder symmetries responsible for the vanishing of Love numbers. In the Kerr case, we compare different near-zone approximations in the literature, and focus on the implementation that retains the symmetries of the static limit. We also describe the relation to spin-1 and 2 perturbations.
Journal Article