1,694 results on '"Hill, Michael P."'
Search Results
102. A new formulation of the equivariant slice filtration with applications to $C_p$-slices
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Hill, Michael A. and Yarnall, Carolyn
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Mathematics - Algebraic Topology ,55N91, 55P91, 55Q10 - Abstract
This paper provides a new way to understand the equivariant slice filtration. We give a new, readily checked condition for determining when a $G$-spectrum is slice $n$-connective. In particular, we show that a $G$-spectrum is slice greater than or equal to $n$ if and only if for all subgroups $H$, the $H$-geometric fixed points are $(n/|H|-1)$-connected. We use this to determine when smashing with a virtual representation sphere $S^V$ induces an equivalence between various slice categories. Using this, we give an explicit formula for the slices for an arbitrary $C_p$-spectrum and show how a very small number of functors determine all of the slices for $C_{p^n}$-spectra., Comment: Final version, to appear in Proceedings of the AMS
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- 2017
103. On the Andre-Quillen homology of Tambara functors
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Hill, Michael A.
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Mathematics - Algebraic Topology ,Mathematics - Group Theory ,Mathematics - K-Theory and Homology - Abstract
We lift to equivariant algebra three closely related classical algebraic concepts: abelian group objects in augmented commutative algebras, derivations, and K\"ahler differentials. We define Mackey functor objects in the category of Tambara functors augmented to a fixed Tambara functor $\underline{R}$, and we show that the usual square-zero extension gives an equivalence of categories between these Mackey functor objects and ordinary modules over $\underline{R}$. We then describe the natural generalization to Tambara functors of a derivation, building on the intuition that a Tambara functor has products twisted by arbitrary finite $G$-sets, and we connect this to square-zero extensions in the expected way. Finally, we show that there is an appropriate form of K\"ahler differentials which satisfy the classical relation that derivations out of $\underline{R}$ are the same as maps out of the K\"ahler differentials.
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- 2017
104. Alumanyl Reduction, Reductive Coupling and C–H Isomerization of Organic Nitriles.
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Shere, Henry T. W., Liu, Han-Ying, Hill, Michael S., and Mahon, Mary F.
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- 2024
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105. HERMES-24 Score Derivation and Validation for Simple and Robust Outcome Prediction After Large Vessel Occlusion Treatment.
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Koji Tanaka, Brown, Scott, Goyal, Mayank, Menon, Bijoy K., Campbell, Bruce C. V., Mitchell, Peter J., Jovin, Tudor G., Saver, Jeffrey L., Muir, Keith W., White, Phil M., Bracard, Serge, Guillemin, Francis, Roos, Yvo B. W. E. M., van Zwam, Wim H., Najm, Mohamed, Dowlatshahi, Dar, Hill, Michael D., and Demchuk, Andrew M.
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- 2024
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106. Adaptive Randomization Method to Prevent Extreme Instances of Group Size and Covariate Imbalance in Stroke Trials.
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Italiano, Dominic, Campbell, Bruce, Hill, Michael D., Johns, Hannah T., and Churilov, Leonid
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- 2024
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107. Exploring the Limits of Endovascular Therapy for Large Core Patients: Where Do We Need More Data?
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Albers, Gregory W., Heit, Jeremy J., Lansberg, Maarten G., Inoue, Manabu, Huo, Xiaochuan, Yedavalli, Vivek S., Seners, Pierre, McCullough-Hicks, Margy, Cereda, Carlo W., Tsai, Jenny P., Mistry, Eva A., Chatterjee, Arindam R., Derdeyn, Colin P., Khatri, Pooja, Olivot, J.M., Hill, Michael D., Saver, Jeffrey L., and Fisher, Marc
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- 2024
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108. Combining Early Ischemic Change and Collateral Extent for Functional Outcomes After Endovascular Therapy: An Analysis From AcT Trial.
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Tanaka, Koji, Kaveeta, Chitapa, Pensato, Umberto, Zhang, Jianhai, Bala, Fouzi, Alhabli, Ibrahim, Horn, MacKenzie, Ademola, Ayoola, Almekhlafi, Mohammed, Ganesh, Aravind, Buck, Brian, Tkach, Aleksander, Catanese, Luciana, Dowlatshahi, Dar, Shankar, Jai, Poppe, Alexandre Y., Shamy, Michel, Qiu, Wu, Swartz, Richard H., and Hill, Michael D.
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- 2024
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109. Equivariant symmetric monoidal structures
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Hill, Michael A. and Hopkins, Michael J.
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Mathematics - Algebraic Topology ,Mathematics - Category Theory ,55N91, 19D23, 18D50, 18D35 - Abstract
Building on structure observed in equivariant homotopy theory, we define an equivariant generalization of a symmetric monoidal category: a $G$-symmetric monoidal category. These record not only the symmetric monoidal products but also symmetric monoidal powers indexed by arbitrary finite $G$-sets. We then define $G$-commutative monoids to be the natural extension of ordinary commutative monoids to this new context. Using this machinery, we then describe when Bousfield localization in equivariant spectra preserves certain operadic algebra structures, and we explore the consequences of our definitions for categories of modules over a $G$-commutative monoid., Comment: 23 pages
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- 2016
110. Preserving torsion orders when embedding into groups with `small' finite presentations
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Chiodo, Maurice and Hill, Michael E.
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Mathematics - Group Theory ,20E06, 20F05 - Abstract
We give a complete survey of a construction by Boone and Collins for embedding any finitely presented group into one with $8$ generators and $26$ relations. We show that this embedding preserves the set of orders of torsion elements, and in particular torsion-freeness. We combine this with the independent results of Belegradek and Chiodo to prove that there is an $8$-generator $26$-relator universal finitely presented torsion-free group (one into which all finitely presented torsion-free groups embed)., Comment: 14 pages. First version. Comments welcome
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- 2016
111. How ‘research impact bonds’ could transform science funding
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Hill, Michael
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- 2023
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112. Curating the Imagined Past: World Building in the History Curriculum
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Hill, Michael
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Mike Hill was concerned that his students were unable to genuinely inhabit the historical places they encountered in his lessons. Drawing on fields as varied as history-teacher research, philosophy, and literary and media theory, Hill identified ways to curate his students' constructions of 'secondary worlds' in the historical past, including narrative, maps, and material culture. In this article, Hill argues that teachers can powerfully shape their students' imagined pasts through careful curriculum planning, and outlines how doing so gave greater meaning to his students' understandings of the Weimar Republic.
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- 2020
113. Clinical impact of EVT with failed reperfusion in patients with acute ischemic stroke: results from the ESCAPE and ESCAPE-NA1 trials
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Ospel, Johanna M., Hill, Michael D., Demchuk, Andrew, Menon, Bijoy K., Thornton, John, Rempel, Jeremy, Almekhlafi, Mohammed A., Ganesh, Aravind, Kappelhof, Manon, Singh, Nishita, Cimflova, Petra, Kashani, Nima, Bala, Fouzi, Kim, Beom Joon, McTaggart, Ryan, Poppe, Alexandre, Nogueira, Raul G., Tymianski, Michael, and Goyal, Mayank
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- 2021
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114. Fatigue crack growth rates of X100 steel welds in high pressure hydrogen gas considering residual stress effects
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Ronevich, Joseph A, D'Elia, Christopher R, and Hill, Michael R
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Hydrogen embrittlement ,Residual stress ,High strength pipeline steels ,Fatigue crack growth rate ,High pressure hydrogen ,Mechanical Engineering & Transports - Abstract
Fatigue crack growth rate (FCGR) data were measured in high pressure hydrogen gas versus stress intensity factor range (ΔK) in specimens removed from a X100 welded steel pipe. Three distinct regions of the pipe weld were examined: base metal, weld fusion zone, and heat affected zone. Tests were performed at a load ratio (R) of 0.5, frequency of 1 Hz, and at a hydrogen gas pressure of 21 MPa. Tests were also performed in air at 10 Hz as a reference. Fatigue crack growth rates were observed to be over an order of magnitude higher for tests performed in hydrogen compared to the rates from tests in air. Residual stress measurements were collected on identical specimens cut from the base metal, weld, and heat affected zone to account for their influence on measured FCGR data. The slitting method provided residual stress and residual stress intensity factor (Kres), the effect of which was removed from the FCGR data using Knorm in order to provide a more direct comparison of crack growth resistance of the base metal, weld and heat affected zone. Prior to accounting for residual stress, FCGR in hydrogen gas appeared to be highest in the weld fusion zone. After accounting for residual stress effects, the weld fusion zone FCGR data converged to the base metal FCGR data, which underscores the importance of accounting for residual stress effects when assessing fatigue performance.
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- 2018
115. Alpha1 -adrenergic stimulation selectively enhances endothelium-mediated vasodilation in rat cremaster arteries.
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Mishra, Ramesh C, Rahman, Mohammad M, Davis, Michael J, Wulff, Heike, Hill, Michael A, and Braun, Andrew P
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Muscle ,Smooth ,Vascular ,Endothelium ,Vascular ,Animals ,Rats ,Sprague-Dawley ,Norepinephrine ,Phenylephrine ,Acetylcholine ,Calcium Channels ,L-Type ,Potassium Channels ,Voltage-Gated ,Receptors ,Adrenergic ,alpha-1 ,Membrane Potentials ,Vasodilation ,Male ,Nitric Oxide Synthase Type III ,Adrenergic alpha-1 Receptor Agonists ,eNOS ,Endothelium ,KCa channel ,myogenic tone ,vasodilation ,α1-Adrenoceptor ,eNOS ,Calcium Channels ,L-Type ,Vascular ,Muscle ,Smooth ,Potassium Channels ,Voltage-Gated ,Rats ,Sprague-Dawley ,Receptors ,Adrenergic ,alpha-1 ,Physiology ,Clinical Sciences ,Medical Physiology - Abstract
We have systematically investigated how vascular smooth muscle α1 -adrenoceptor activation impacts endothelium-mediated vasodilation in isolated, myogenically active, rat cremaster muscle 1A arteries. Cannulated cremaster arteries were pressurized intraluminally to 70 mmHg to induce myogenic tone, and exposed to vasoactive agents via bath superfusion at 34°C. Smooth muscle membrane potential was measured via sharp microelectrode recordings in pressurized, myogenic arteries. The α1 -adrenergic agonist phenylephrine (25-100 nmol/L) produced further constriction of myogenic arteries, but did not alter the vasorelaxant responses to acetylcholine (0.3 μmol/L), SKA-31 (an activator of endothelial Ca2+ -dependent K+ channels) (3 μmol/L) or sodium nitroprusside (10 μmol/L). Exposure to 0.25-1 μmol/L phenylephrine or 1 μmol/L norepinephrine generated more robust constrictions, and also enhanced the vasodilations evoked by acetylcholine and SKA-31, but not by sodium nitroprusside. In contrast, the thromboxane receptor agonist U46619 (250 nmol/L) dampened responses to all three vasodilators. Phenylephrine exposure depolarized myogenic arteries, and mimicking this effect with 4-aminopyridine (1 mmol/L) was sufficient to augment the SKA-31-evoked vasodilation. Inhibition of L-type Ca2+ channels by 1 μmol/L nifedipine decreased myogenic tone, phenylephrine-induced constriction and prevented α1 -adrenergic enhancement of endothelium-evoked vasodilation; these latter deficits were overcome by exposure to 3 and 10 μmol/L phenylephrine. Mechanistically, augmentation of ACh-evoked dilation by phenylephrine was dampened by eNOS inhibition and abolished by blockade of endothelial KCa channels. Collectively, these data suggest that increasing α1 -adrenoceptor activation beyond a threshold level augments endothelium-evoked vasodilation, likely by triggering transcellular signaling between smooth muscle and the endothelium. Physiologically, this negative feedback process may serve as a "brake" to limit the extent of vasoconstriction in the skeletal microcirculation evoked by the elevated sympathetic tone.
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- 2018
116. Transmural remodeling of right ventricular myocardium in response to pulmonary arterial hypertension.
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Avazmohammadi, Reza, Hill, Michael, Simon, Marc, and Sacks, Michael
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Pulmonary arterial hypertension (PAH) imposes substantial pressure overload on the right ventricular free wall (RVFW), leading to myofiber hypertrophy and remodeling of its collagen fiber architecture. The transmural nature of these adaptations and their effects on the macroscopic mechanical behavior of the RVFW remain largely unexplored. In the present work, we extended our constitutive model for RVFW myocardium to investigate the transmural mechanical and structural remodeling post-PAH. Recent murine experimental studies provided us with comprehensive histomorphological and biaxial mechanical data for viable, passive myocardium for normal and post hypertensive cases. Multiple fiber-level remodeling events were found to be localized in the midwall region (40% < depth < 60%): (i) reorientation and alignment of both myo- and collagen fibers towards longitudinal (apex-to-outflow tract) direction, (ii) substantial increase in the rate of the recruitment of collagen fibers with strain, and (iii) a corresponding increase in the mechanical interactions between the collagen and myofibers. These adaptations suggest a denser and more fibrous connective tissue in the midwall region, and led to a substantially stiffer mechanical response along the longitudinal direction in post-PAH tissues. Moreover, using a Laplace-type mechanical equilibrium analysis of the right ventricle to approximate the wall stress state, we estimated that the longitudinal component of stress remained higher in the hypertensive state while the circumferential component approximately maintained homeostasis values. This result was consistent with our observation from the fiber- and tissue-level remodeling that longitudinally oriented collagen fibers, localized in the midwall region, dominated the remodeling process. The findings of this study highlight the need for more integrated cellular-tissue-organ analysis to better understand the remodeling events during PAH and design interventions.
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- 2017
117. Theta-burst microstimulation in the human entorhinal area improves memory specificity.
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Titiz, Ali S, Hill, Michael RH, Mankin, Emily A, M Aghajan, Zahra, Eliashiv, Dawn, Tchemodanov, Natalia, Maoz, Uri, Stern, John, Tran, Michelle E, Schuette, Peter, Behnke, Eric, Suthana, Nanthia A, and Fried, Itzhak
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Entorhinal Cortex ,Humans ,Theta Rhythm ,Electric Stimulation ,Microelectrodes ,Memory ,Long-Term Potentiation ,deep brain stimulation ,episodic memory ,hippocampus ,human ,human biology ,medial temporal lobe ,medicine ,microstimulation ,neuroscience ,Neurodegenerative ,Brain Disorders ,Mental Health ,Neurosciences ,Mental health ,Biochemistry and Cell Biology - Abstract
The hippocampus is critical for episodic memory, and synaptic changes induced by long-term potentiation (LTP) are thought to underlie memory formation. In rodents, hippocampal LTP may be induced through electrical stimulation of the perforant path. To test whether similar techniques could improve episodic memory in humans, we implemented a microstimulation technique that allowed delivery of low-current electrical stimulation via 100 μm-diameter microelectrodes. As thirteen neurosurgical patients performed a person recognition task, microstimulation was applied in a theta-burst pattern, shown to optimally induce LTP. Microstimulation in the right entorhinal area during learning significantly improved subsequent memory specificity for novel portraits; participants were able both to recognize previously-viewed photos and reject similar lures. These results suggest that microstimulation with physiologic level currents-a radical departure from commonly used deep brain stimulation protocols-is sufficient to modulate human behavior and provides an avenue for refined interrogation of the circuits involved in human memory.
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- 2017
118. Residual Stress From Cold Expansion of Fastener Holes: Measurement, Eigenstrain, and Process Finite Element Modeling
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Ribeiro, Renan L and Hill, Michael R
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cold expansion ,residual stress ,finite element analysis ,eigenstrain ,Manufacturing Engineering ,Materials Engineering ,Mechanical Engineering ,Materials - Abstract
Cold expansion (CX) is a material processing technique that has been widely used in the aircraft industry to enhance fatigue life of structural components containing holes. CX introduces compressive hoop residual stresses that slow crack growth near the hole edge. The objective of this paper is to predict residual stresses arising from cold expansion using two different finite element (FE) approaches, and compare the results to measurement data obtained by the contour method. The paper considers single-hole, double-hole, and triple-hole configurations with three different edge margins. The first FE approach considers process modeling, and includes elastic-plastic behavior, while the second approach is based on the eigenstrain method, and includes only elastic behavior. The results obtained from the FE models are in good agreement with one another, and with measurement data, especially close to the holes, and with respect to the effect of edge margin on the residual stress distributions. The distribution of the residual stress and equivalent plastic strain around the holes is also explored, and the results are discussed in detail. The eigenstrain method was found to be very useful, providing generally accurate predictions of residual stress.
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- 2017
119. Incomplete Tambara functors
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Blumberg, Andrew J. and Hill, Michael A.
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Mathematics - Algebraic Topology ,Mathematics - Category Theory - Abstract
For a "genuine" equivariant commutative ring spectrum $R$, $\pi_0(R)$ admits a rich algebraic structure known as a Tambara functor. This algebraic structure mirrors the structure on $R$ arising from the existence of multiplicative norm maps. Motivated by the surprising fact that Bousfield localization can destroy some of the norm maps, in previous work we studied equivariant commutative ring structures parametrized by $N_\infty$ operads. In a precise sense, these interpolate between "naive" and "genuine" equivariant ring structures. In this paper, we describe the algebraic analogue of $N_\infty$ ring structures. We introduce and study categories of incomplete Tambara functors, described in terms of certain categories of bispans. Incomplete Tambara functors arise as $\pi_0$ of $N_\infty$ algebras, and interpolate between Green functors and Tambara functors. We classify all incomplete Tambara functors in terms of a basic structural result about polynomial functors. This classification gives a conceptual justification for our prior description of $N_\infty$ operads and also allows us to easily describe the properties of the category of incomplete Tambara functors.
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- 2016
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120. Inherent rhythm of smooth muscle cells in rat mesenteric arterioles: an eigensystem formulation
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Ho, I Lin, Moshkforoush, Arash, Hong, Kwangseok, Meininger, Gerald A., Hill, Michael A., Tsoukias, Nikolaos M., and Kuo, Watson
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Quantitative Biology - Cell Behavior ,Physics - Biological Physics - Abstract
On the basis of experimental data and mathematical equations in the literature, we remodel the ionic dynamics of smooth muscle cells (SMCs) as an eigensystem formulation, which is valid for investigating finite variations of variables from the equilibrium like in common experimental operations. This algorithm provides an alternate viewpoint from frequency-domain analysis and enables one to probe functionalities of SMC's rhythm by means of a resonance-related mechanism. Numerical results show three types of calcium oscillations of SMCs in mesenteric arterioles: spontaneous calcium oscillation, agonist-dependent calcium oscillation, and agonist-dependent calcium spike. For simple single and double SMCs, we demonstrate properties of synchronization among complex signals related to calcium oscillations, and show different correlation relations between calcium and voltage signals for various synchronization and resonance conditions. For practical cell clusters, our analyses indicate that the rhythm of SMCs could (1) benefit enhancements of signal communications among remote cells, (2) respond to a significant calcium peaking against transient stimulations for triggering globally-oscillating modes, and (3) characterize the globally-oscillating modes via frog-leap (non-molecular-diffusion) calcium waves across inhomogeneous SMCs., Comment: 56 pages, 18 figures
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- 2016
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121. G-symmetric monoidal categories of modules over equivariant commutative ring spectra
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Blumberg, Andrew J. and Hill, Michael A.
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Mathematics - Algebraic Topology - Abstract
We describe the multiplicative structures that arise on categories of equivariant modules over certain equivariant commutative ring spectra. Building on our previous work on N-infinity ring spectra, we construct categories of equivariant operadic modules over N-infinity rings that are structured by equivariant linear isometries operads. These categories of modules are endowed with equivariant symmetric monoidal structures, which amounts to the structure of an "incomplete Mackey functor in homotopical categories". In particular, we construct internal norms which satisfy the double coset formula. We regard the work of this paper as a first step towards equivariant derived algebraic geometry., Comment: Revised to include appendix on compact Lie groups, reflect referee comments
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- 2015
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122. The Slice Spectral Sequence for certain $RO(C_{p^n})$-graded Suspensions of $H\underline{\mathbb Z}$
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Hill, Michael A., Hopkins, Michael J., and Ravenel, Douglas C.
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Mathematics - Algebraic Topology - Abstract
We study the slice filtration and associated spectral sequence for a family of $RO(C_{p^{n}})$-graded suspensions of the Eilenberg-MacLane spectrum for the constant Mackey functor $\underline{\mathbb Z}$. Since $H\underline{\mathbb Z}$ is the zero slice of the sphere spectrum, this begins an analysis of how one can describe the slices of a suspension in terms of the original slices., Comment: 25 pages, 3 figures, comments welcome!
- Published
- 2015
123. Effects of ultrasonic impact treatment on weld microstructure, hardness, and residual stress
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Liu, Chuan, Chen, Dongjun, Hill, Michael R, Tran, Minh N, and Zou, Jiasheng
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Layered ultrasonic impact treatment ,thick weld joint ,microstructure ,hardness ,welding residual stress ,Materials Engineering ,Mechanical Engineering ,Materials - Abstract
Layered ultrasonic impact treatment (LUIT) was used on V-groove welds in 55 mm Q345 steel plate. Two welds were prepared, one by conventional gas metal arc welding (GMAW) and the other by GMAW and LUIT, where impact treatment was performed at nine stages during filling of the 28-pass weld. Microstructure, hardness, and residual stress in the welds were compared. While residual stress is very similar, there are significant differences in microstructure and hardness. The LUIT weld has mainly equiaxed grains and uniform hardness, while the conventional weld has columnar grains and a hardness gradient. It appears that beads in the LUIT weld did not exhibit columnar grain growth, and instead equiaxed grains grew from the fusion boundary into the weld.
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- 2017
124. A novel constitutive model for passive right ventricular myocardium: evidence for myofiber–collagen fiber mechanical coupling
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Avazmohammadi, Reza, Hill, Michael R, Simon, Marc A, Zhang, Will, and Sacks, Michael S
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Engineering ,Biomedical Engineering ,Cardiovascular ,Bioengineering ,Heart Disease ,Animals ,Collagen ,Extracellular Matrix ,Heart ,Heart Ventricles ,Hypertension ,Pulmonary ,Mice ,Models ,Biological ,Myofibrils ,Stress ,Mechanical ,Mechanical Engineering ,Biomedical engineering - Abstract
The function of right ventricle (RV) is recognized to play a key role in the development of many cardiopulmonary disorders, such as pulmonary arterial hypertension (PAH). Given the strong link between tissue structure and mechanical behavior, there remains a need for a myocardial constitutive model that accurately accounts for right ventricular myocardium architecture. Moreover, most available myocardial constitutive models approach myocardium at the length scale of mean fiber orientation and do not explicitly account for different fibrous constituents and possible interactions among them. In the present work, we developed a fiber-level constitutive model for the passive mechanical behavior of the right ventricular free wall (RVFW). The model explicitly separates the mechanical contributions of myofiber and collagen fiber ensembles, and accounts for the mechanical interactions between them. To obtain model parameters for the healthy passive RVFW, the model was informed by transmural orientation distribution measurements of myo- and collagen fibers and was fit to the mechanical testing data, where both sets of data were obtained from recent experimental studies on non-contractile, but viable, murine RVFW specimens. Results supported the hypothesis that in the low-strain regime, the behavior of the RVFW is governed by myofiber response alone, which does not demonstrate any coupling between different myofiber ensembles. At higher strains, the collagen fibers and their interactions with myofibers begin to gradually contribute and dominate the behavior as recruitment proceeds. Due to the use of viable myocardial tissue, the contribution of myofibers was significant at all strains with the predicted tensile modulus of [Formula: see text]32 kPa. This was in contrast to earlier reports (Horowitz et al. 1988) where the contribution of myofibers was found to be insignificant. Also, we found that the interaction between myo- and collagen fibers was greatest under equibiaxial strain, with its contribution to the total stress not exceeding 20 %. The present model can be applied to organ-level computational models of right ventricular dysfunction for efficient diagnosis and evaluation of pulmonary hypertension disorder.
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- 2017
125. Time From Hospital Arrival Until Endovascular Thrombectomy and Patient-Reported Outcomes in Acute Ischemic Stroke
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Joundi, Raed A., Smith, Eric E., Ganesh, Aravind, Nogueira, Raul G., McTaggart, Ryan A., Demchuk, Andrew M., Poppe, Alexandre Y., Rempel, Jeremy L., Field, Thalia S., Dowlatshahi, Dar, Sahlas, Jim, Swartz, Richard, Shah, Ruchir, Sauvageau, Eric, Puetz, Volker, Silver, Frank L., Campbell, Bruce, Chapot, René, Tymianski, Michael, Goyal, Mayank, and Hill, Michael D.
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IMPORTANCE: The time-benefit association of endovascular thrombectomy (EVT) in ischemic stroke with patient-reported outcomes is unknown. OBJECTIVE: To assess the time-dependent association of EVT with self-reported quality of life in patients with acute ischemic stroke. DESIGN, SETTING, AND PARTICIPANTS: Data were used from the Safety and Efficacy of Nerinetide in Subjects Undergoing Endovascular Thrombectomy for Stroke (ESCAPE-NA1) trial, which tested the effect of nerinetide on functional outcomes in patients with large vessel occlusion undergoing EVT and enrolled patients from March 1, 2017, to August 12, 2019. The ESCAPE-NA1 trial was an international randomized clinical trial that recruited patients from 7 countries. Patients with EuroQol 5-dimension 5-level (EQ-5D-5L) index values at 90 days and survivors with complete domain scores were included in the current study. Data were analyzed from July to September 2023. EXPOSURE: Hospital arrival to arterial puncture time and other time metrics. MAIN OUTCOMES AND MEASURES: EQ-5D-5L index scores were calculated at 90 days using country-specific value sets. The association between time from hospital arrival to EVT arterial-access (door-to-puncture) and EQ-5D-5L index score, quality-adjusted life years, and visual analog scale (EQ-VAS) were evaluated using quantile regression, adjusting for age, sex, stroke severity, stroke imaging, wake-up stroke, alteplase, and nerinetide treatment and accounting for clustering by site. Using logistic regression, the association between door-to-puncture time and reporting no or slight symptoms (compared with moderate, severe, or extreme problems) was determined in each domain (mobility, self-care, usual activities, pain or discomfort, and anxiety or depression) or across all domains. Time from stroke onset was also evaluated, and missing data were imputed in sensitivity analyses. RESULTS: Among 1105 patients in the ESCAPE-NA1 trial, there were 1043 patients with EQ-5D-5L index values at 90 days, among whom 147 had died and were given a score of 0, and 1039 patients (mean [SD] age, 69.0 [13.7] years; 527 male [50.7%]) in the final analysis as 4 did not receive EVT. There were 896 survivors with complete domain scores at 90 days. There was a strong association between door-to-puncture time and EQ-5D-5L index score (increase of 0.03; 95% CI, 0.02-0.04 per 15 minutes of earlier treatment), quality-adjusted life years (increase of 0.29; 95% CI, 0.08-0.49 per 15 minutes of earlier treatment), and EQ-VAS (increase of 1.65; 95% CI, 0.56-2.72 per 15 minutes of earlier treatment). Each 15 minutes of faster door-to-puncture time was associated with higher probability of no or slight problems in each of 5 domains and all domains concurrently (range from 1.86%; 95% CI, 1.14-2.58 for pain or discomfort to 3.55%; 95% CI, 2.06-5.04 for all domains concurrently). Door-to-puncture time less than 60 minutes was associated higher odds of no or slight problems in each domain, ranging from odds ratios of 1.49 (95% CI, 1.13-1.95) for pain or discomfort to 2.59 (95% CI, 1.83-3.68) for mobility, with numbers needed to treat ranging from 7 to 17. Results were similar after multiple imputation of missing data and attenuated when evaluating time from stroke onset. CONCLUSIONS AND RELEVANCE: Results suggest that faster door-to-puncture EVT time was strongly associated with better health-related quality of life across all domains. These results support the beneficial impact of door-to-treatment speed on patient-reported outcomes and should encourage efforts to improve patient-centered care in acute stroke by optimizing in-hospital processes and workflows.
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- 2024
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126. Two-dimensional mapping of residual stresses in a thick dissimilar weld using contour method, deep hole drilling, and neutron diffraction
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Woo, Wanchuck, An, Gyu Baek, Truman, Christopher E, Jiang, Wenchun, and Hill, Michael R
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Chemical Sciences ,Engineering ,Materials - Abstract
Residual stress variations were determined through the thickness of a 70-mm-thick ferritic–austenitic dissimilar steel weld using contour method, deep hole drilling, and neutron diffraction. The result shows that significant tensile stresses were distributed distinctly along the interface between ferritic and austenitic phases. The band of the large tensile stresses was about 8 mm wide and the magnitude reached 400 MPa, which is approaching 100 % of the yield strength of the base metal, near the top surface (about 15 % of the depth). It is attributed to the large difference (5.8 × 10−6 1/°C) of the thermal expansion coefficient between ferritic and austenitic steels of the interface. The microstructure analysis elucidates that the martensitic phase prevailed near the interface and results in microhardness increases.
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- 2016
127. Weight functions for a finite width plate with single or double radial cracks at a circular hole
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Kim, Jihwi and Hill, Michael R
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Weight function ,Radial crack ,Open hole ,Stress intensity factor ,Fracture mechanics ,Mechanical Engineering & Transports - Abstract
This work develops accurate weight functions for a single crack at a hole in a finite width plate for various hole sizes. In order to develop an accurate weight function, we first obtain accurate stress intensity factors, using the finite element method (FEM), for a reference load case of uniform stress on the crack line. Following the earlier approach for developing a weight function suggested by Wu and Carlsson, we fit the reference stress intensity factor data from FEM to a smooth analytic function; however, for the open hole it is necessary to adopt a piecewise polynomial to fit the stress intensity factor data, in place of the single polynomial suggested by Wu and Carlsson. We validate the new weight function for the case of remote uniform applied stress, which induces a stress field on the crack line exhibiting the well-known stress concentration at the hole, and for which we have accepted stress intensity factor solutions. The new weight functions provide stress intensity factors that agree very well with results from two commercial fracture mechanics software packages. Comparing results from the new and earlier weight functions shows good agreement for some crack line stress fields, but errors of a few percent for other stress fields, with the new weight function providing more reasonable results. The improved quality of the new weight functions is due both to the new reference solution for uniform crack line stress and to the piecewise fit to the reference stress intensity data. Trivial changes to the FEM model allow us to provide additional weight functions for the cases of symmetric double cracks at a hole (by adding a symmetry plane to the FEM mesh) and a single crack at a hole in a square plate (by reducing the length of the FEM mesh).
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- 2016
128. An Equivariant Tensor Product on Mackey Functors
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Hill, Michael A. and Mazur, Kristen
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Mathematics - Algebraic Topology ,19A22, 55P91, 18G99, 20J05 - Abstract
For all subgroups $H$ of a cyclic $p$-group $G$ we define norm functors that build a $G$-Mackey functor from an $H$-Mackey functor. We give an explicit construction of these functors in terms of generators and relations based solely on the intrinsic, algebraic properties of Mackey functors and Tambara functors. We use these norm functors to define a monoidal structure on the category of Mackey functors where Tambara functors are the commutative ring objects.
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- 2015
129. The $C_2$-spectrum $Tmf_1(3)$ and its invertible modules
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Hill, Michael A. and Meier, Lennart
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Mathematics - Algebraic Topology ,55P42, 55N34 - Abstract
We explore the $C_2$-equivariant spectra $Tmf_1(3)$ and $TMF_1(3)$. In particular, we compute their $C_2$-equivariant Picard groups and the $C_2$-equivariant Anderson dual of $Tmf_1(3)$. This implies corresponding results for the fixed point spectra $TMF_0(3)$ and $Tmf_0(3)$. Furthermore, we prove a Real Landweber exact functor theorem., Comment: Final version to appear in AGT. 51 pages
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- 2015
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130. On the fate of $\eta^3$ in higher analogues of Real bordism
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Hill, Michael A.
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Mathematics - Algebraic Topology - Abstract
We show that the cube of the Hopf map $\eta$ maps to zero under the Hurewicz map for all fixed points of all norms to cyclic $2$-groups of the Landweber-Araki Real bordism spectrum. Using that the slice spectral sequence is a spectral sequence of Mackey functors, we compute the relevant portion of the homotopy groups of these fixed points, showing that multiplication by $4$ annihilates $\pi_{3}$.
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- 2015
131. The slice spectral sequence for the $C_{4}$ analog of real $K$-theory
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Hill, Michael A., Hopkins, Michael J., and Ravenel, Douglas C.
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Mathematics - Algebraic Topology ,55Q10 (primary), and 55Q91, 55P42, 55R45, 55T99 (secondary) - Abstract
We describe the slice spectral sequence of a 32-periodic $C_{4}$-spectrum $K_{[2]}$ related to the $C_{4}$ norm ${N_{C_{2}}^{C_{4}}MU_{\bf R}}$ of the real cobordism spectrum $MU_{\bf R}$. We will give it as a spectral sequence of Mackey functors converging to the graded Mackey functor $\underline{\pi }_{*}K_{[2]}$, complete with differentials and exotic extensions in the Mackey functor structure. The slice spectral sequence for the 8-periodic real $K$-theory spectrum $K_{\bf R}$ was first analyzed by Dugger. The $C_{8}$ analog of $K_{[2]}$ is 256-periodic and detects the Kervaire invariant classes $\theta_{j}$ in the stable homotopy groups of spheres. A partial analysis of its slice spectral sequence led to the solution to the Kervaire invariant problem, namely the theorem that $\theta_{j}$ does not exist for $j\geq 7$., Comment: 82 pages, 4 tables and 17 figures, some using color
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- 2015
132. Association Between Time to Treatment With Endovascular Thrombectomy and Home-Time After Acute Ischemic Stroke.
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Joundi, Raed A., Hill, Michael D., Stang, Jillian, Nicol, Dana, Ying Xin Yu, Amy, Kapral, Moira K., King, James A., Halabi, Mary-Lou, and Smith, Eric E.
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- 2024
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133. Heteroallene Insertions into Tin(II) Alkoxide Bonds.
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Ryan, Aidan T., Brookes, Andrew, Straiton, Andrew J., Wildsmith, Thomas, Lowe, John P., Molloy, Kieran C., Hill, Michael S., and Johnson, Andrew L.
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- 2024
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134. Risk Factors for Perinatal Arterial Ischemic Stroke: A Machine Learning Approach.
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Srivastava, Ratika, Cole, Lauran, Amador, Kimberly, Forkert, Nils Daniel, Dunbar, Mary, Shevell, Michael I., Oskoui, Maryam, Basu, Anna P., Rivkin, Michael J., Shany, Eilon, de Vries, Linda S., Dewey, Deborah, Letourneau, Nicole, Mouches, Pauline, Hill, Michael D., and Kirton, Adam
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- 2024
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135. Influence of Infarct Morphology and Patterns on Cognitive Outcomes After Endovascular Thrombectomy.
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Ospel, Johanna Maria, Rinkel, Leon, Ganesh, Aravind, Demchuk, Andrew, Joshi, Manish, Poppe, Alexandre, McTaggart, Ryan, Nogueira, Raul, Menon, Bijoy, Tymianski, Michael, Hill, Michael Douglas, and Goyal, Mayank
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- 2024
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136. Minimal clinically important difference in Alzheimer's disease: Rapid review.
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Muir, Ryan T., Hill, Michael D., Black, Sandra E., and Smith, Eric E.
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INTRODUCTION: We conducted a rapid systematic review of minimal clinically important differences (MCIDs) for Alzheimer's disease (AD) trial endpoints. METHODS: Two reviewers searched EMBASE, MEDLINE, and PubMed from inception to June 4, 2023. RESULTS: Ten articles were retrieved. For mild cognitive impairment (MCI), a change of +2 to +3 points on the Alzheimer's Disease Assessment Scale–Cognitive Subscale (ADAS‐Cog), +1 points on the Clinical Dementia Rating scale sum of boxes (CDR‐SB), −5 points on the integrated Alzheimer's Disease Rating Scale (iADRS), or −1 to −2 points on the Mini‐Mental State Examination (MMSE) was considered meaningful. For patients with mild AD, a change of +3 on the ADAS‐Cog, +2 points on CDR‐SB, −9 points on the iADRS, or −2 points on the MMSE was considered meaningful. For patients with moderate to severe AD, a change of +2 points on the CDR‐SB or a change of −1.4 to −3 points on the MMSE was considered meaningful. CONCLUSION: This review identified previously published MCIDs for AD trial endpoints. Input from patients and caregivers will be needed to derive more meaningful endpoints and thresholds. Highlights: This systematic rapid review identified thresholds for minimal clinically important differences (MCIDs) for recently used Alzheimer's disease (AD) trial endpoints: Alzheimer's Disease Assessment Scale–Cognitive Subscale (ADAS‐Cog), Clinical Dementia Rating scale sum of boxes (CDR‐SB), integrated Alzheimer's Disease Rating Scale (iADRS), Mini‐Mental State Examination (MMSE).MCIDs were higher for more severe stages of AD.Average treatment effects in recent trials of anti‐amyloid disease modifying monoclonal antibodies are lower than previously published MCIDs.In future trials of disease modifying treatments for AD, the proportion of participants in each treatment group that experienced a clinically meaningful decline could be reported.More work is needed to incorporate the values and preferences of patients and care partners in deriving MCIDs. [ABSTRACT FROM AUTHOR]
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- 2024
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137. [{SiNDipp}MgNa]2: A Potent Molecular Reducing Agent.
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Liu, Han-Ying, Neale, Samuel E., Hill, Michael S., Mahon, Mary F., McMullin, Claire L., and Richards, Emma
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- 2024
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138. What Is a Meaningful Difference When Using Infarct Volume as the Primary Outcome?: Results From the HERMES Database.
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Rinkel, Leon A., Ospel, Johanna M., Brown, Scott B., Campbell, Bruce C.V., Dippel, Diederik W.J., Demchuk, Andrew M., Majoie, Charles B.L.M., Mitchell, Peter J., Bracard, Serge, Guillemin, Francis, Jovin, Tudor G., Muir, Keith W., White, Philip, Saver, Jeffrey L., Hill, Michael D., and Goyal, Mayank
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- 2024
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139. A benchmark fracture mechanics solution for a two-dimensional eigenstrain problem considering residual stress, the stress intensity factor, and superposition
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Ribeiro, Renan L and Hill, Michael R
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Eigenstrain ,Residual stress ,Finite element analysis ,Stress intensity factor ,Weight function ,Mechanical Engineering & Transports - Abstract
Eigenstrain is a distributed strain field considered in mechanics that is particularly helpful in evaluating residual stress fields in the finite element method, and estimating the stress intensity factor due to residual stress in cracked components. The objective of this paper is to provide a solution for a simple eigenstrain problem in a two-dimensional rectangular domain that can serve as a benchmark for validation of fracture mechanics analysis methods. The solution provides residual stress fields and the stress intensity factor for a single edge crack as a function of crack size. Documenting the benchmark provides opportunities to demonstrate the correlation of different means to determine the stress intensity factor and to highlight details in implementing stress intensity factor calculations.
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- 2016
140. Predicting Intracerebral Hemorrhage Growth With the Spot Sign
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Dowlatshahi, Dar, Brouwers, H Bart, Demchuk, Andrew M, Hill, Michael D, Aviv, Richard I, Ufholz, Lee-Anne, Reaume, Michael, Wintermark, Max, Hemphill, J Claude, Murai, Yasuo, Wang, Yongjun, Zhao, Xingquan, Wang, Yilong, Li, Na, Sorimachi, Takatoshi, Matsumae, Mitsunori, Steiner, Thorsten, Rizos, Timolaos, Greenberg, Steven M, Romero, Javier M, Rosand, Jonathan, Goldstein, Joshua N, and Sharma, Mukul
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Biomedical Imaging ,Stroke ,Detection ,screening and diagnosis ,4.2 Evaluation of markers and technologies ,Cerebral Angiography ,Cerebral Hemorrhage ,Disease Progression ,Hematoma ,Humans ,Predictive Value of Tests ,Time Factors ,Tomography ,X-Ray Computed ,cerebral hemorrhage ,hematoma expansion ,CT angiography ,spot sign ,intracerebral hemorrhage ,Cardiorespiratory Medicine and Haematology ,Clinical Sciences ,Neurosciences ,Neurology & Neurosurgery - Abstract
Background and purposeHematoma expansion after acute intracerebral hemorrhage is common and is associated with early deterioration and poor clinical outcome. The computed tomographic angiography (CTA) spot sign is a promising predictor of expansion; however, frequency and predictive values are variable across studies, possibly because of differences in onset-to-CTA time. We performed a patient-level meta-analysis to define the relationship between onset-to-CTA time and frequency and predictive ability of the spot sign.MethodsWe completed a systematic review for studies of CTA spot sign and hematoma expansion. We subsequently pooled patient-level data on the frequency and predictive values for significant hematoma expansion according to 5 predefined categorized onset-to-CTA times. We calculated spot-sign frequency both as raw and frequency-adjusted rates.ResultsAmong 2051 studies identified, 12 met our inclusion criteria. Baseline hematoma volume, spot-sign status, and time-to-CTA were available for 1176 patients, and 1039 patients had follow-up computed tomographies for hematoma expansion analysis. The overall spot sign frequency was 26%, decreasing from 39% within 2 hours of onset to 13% beyond 8 hours (P
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- 2016
141. Safety and Efficacy of Solitaire Stent Thrombectomy
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Campbell, Bruce CV, Hill, Michael D, Rubiera, Marta, Menon, Bijoy K, Demchuk, Andrew, Donnan, Geoffrey A, Roy, Daniel, Thornton, John, Dorado, Laura, Bonafe, Alain, Levy, Elad I, Diener, Hans-Christoph, Hernández-Pérez, María, Pereira, Vitor Mendes, Blasco, Jordi, Quesada, Helena, Rempel, Jeremy, Jahan, Reza, Davis, Stephen M, Stouch, Bruce C, Mitchell, Peter J, Jovin, Tudor G, Saver, Jeffrey L, and Goyal, Mayank
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Biomedical and Clinical Sciences ,Clinical Sciences ,Neurosciences ,Stroke ,Clinical Trials and Supportive Activities ,Clinical Research ,Brain Disorders ,Good Health and Well Being ,Aged ,Aged ,80 and over ,Brain Ischemia ,Female ,Humans ,Male ,Middle Aged ,Randomized Controlled Trials as Topic ,Statistics as Topic ,Stents ,Thrombectomy ,thrombolysis ,randomized controlled trial ,mechanical thrombectomy ,endovascular treatment ,stent retriever device ,intra-arterial therapy ,meta-analysis ,ischemic stroke ,Cardiorespiratory Medicine and Haematology ,Neurology & Neurosurgery ,Clinical sciences ,Allied health and rehabilitation science - Abstract
Background and purposeRecent positive randomized trials of endovascular therapy for ischemic stroke used predominantly stent retrievers. We pooled data to investigate the efficacy and safety of stent thrombectomy using the Solitaire device in anterior circulation ischemic stroke.MethodsPatient-level data were pooled from trials in which the Solitaire was the only or the predominant device used in a prespecified meta-analysis (SEER Collaboration): Solitaire FR With the Intention for Thrombectomy as Primary Endovascular Treatment (SWIFT PRIME), Endovascular Treatment for Small Core and Anterior Circulation Proximal Occlusion With Emphasis on Minimizing CT to Recanalization Times (ESCAPE), Extending the Time for Thrombolysis in Emergency Neurological Deficits-Intra-Arterial (EXTEND-IA), and Randomized Trial of Revascularization With Solitaire FR Device Versus Best Medical Therapy in the Treatment of Acute Stroke Due to Anterior Circulation Large Vessel Occlusion Presenting Within Eight Hours of Symptom Onset (REVASCAT). The primary outcome was ordinal analysis of modified Rankin Score at 90 days. The primary analysis included all patients in the 4 trials with 2 sensitivity analyses: (1) excluding patients in whom Solitaire was not the first device used and (2) including the 3 Solitaire-only trials (excluding ESCAPE). Secondary outcomes included functional independence (modified Rankin Score 0-2), symptomatic intracerebral hemorrhage, and mortality.ResultsThe primary analysis included 787 patients: 401 randomized to endovascular thrombectomy and 386 to standard care, and 82.6% received intravenous thrombolysis. The common odds ratio for modified Rankin Score improvement was 2.7 (2.0-3.5) with no heterogeneity in effect by age, sex, baseline stroke severity, extent of computed tomography changes, site of occlusion, or pretreatment with alteplase. The number needed to treat to reduce disability was 2.5 and for an extra patient to achieve independent outcome was 4.25 (3.29-5.99). Successful revascularization occurred in 77% treated with Solitaire device. The rate of symptomatic intracerebral hemorrhage and overall mortality did not differ between treatment groups.ConclusionsSolitaire thrombectomy for large vessel ischemic stroke was safe and highly effective with substantially reduced disability. Benefits were consistent in all prespecified subgroups.
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- 2016
142. Association Between CT Angiogram Collaterals and CT Perfusion in the Interventional Management of Stroke III Trial
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Vagal, Achala, Menon, Bijoy K, Foster, Lydia D, Livorine, Anthony, Yeatts, Sharon D, Qazi, Emmad, d'Esterre, Chris, Shi, Junzi, Demchuk, Andrew M, Hill, Michael D, Liebeskind, David S, Tomsick, Thomas, and Goyal, Mayank
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Epidemiology ,Biomedical and Clinical Sciences ,Health Sciences ,Clinical Research ,Stroke ,Cardiovascular ,Brain Disorders ,Biomedical Imaging ,Neurosciences ,Adult ,Aged ,Aged ,80 and over ,Arterial Occlusive Diseases ,Carotid Artery Diseases ,Carotid Artery ,Internal ,Cerebral Angiography ,Cerebrovascular Circulation ,Cohort Studies ,Collateral Circulation ,Female ,Humans ,Infarction ,Middle Cerebral Artery ,Male ,Middle Aged ,Perfusion Imaging ,Prospective Studies ,Tomography ,X-Ray Computed ,carotid artery ,internal ,collateral circulation ,perfusion imaging ,stroke ,tomography ,x-ray computed ,Cardiorespiratory Medicine and Haematology ,Clinical Sciences ,Neurology & Neurosurgery ,Clinical sciences ,Allied health and rehabilitation science - Abstract
Background and purposeCollateral flow can determine ischemic core and tissue at risk. Using the Interventional Management of Stroke (IMS) III trial data, we explored the relationship between computed tomography angiogram (CTA) collateral status and CT perfusion (CTP) parameters.MethodsBaseline CTA collaterals were trichotomized as good, intermediate, and poor, and CTP studies were analyzed to quantify ischemic core, tissue at risk, and mismatch ratios. Kruskal-Wallis and Spearman tests were used to measure the strength of association and correlation between CTA collaterals and CTP parameters.ResultsA total of 95 patients had diagnostic CTP studies in the IMS III trial. Of these, 53 patients had M1/M2 middle cerebral artery±intracranial internal carotid artery occlusion, where baseline CTA collateral grading was performed. CTA collaterals were associated with smaller CTP measured ischemic core volume (P=0.0078) and higher mismatch (P=0.0004). There was moderate negative correlation between collaterals and core (rs=-0.45; 95% confidence interval, -0.64 to -0.20) and moderate positive correlation between collaterals and mismatch (rs=0.53; 95% confidence interval, 0.29-0.71).ConclusionBetter collaterals were associated with smaller ischemic core and higher mismatch in the IMS III trial. Collateral assessment and perfusion imaging identify the same biological construct about ischemic tissue sustenance.
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- 2016
143. Biaxial Residual Stress Mapping for a Dissimilar Metal Welded Nozzle
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Hill, Michael R, Olson, Mitchell D, and DeWald, Adrian T
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Mechanical Engineering ,Mechanical Engineering & Transports - Abstract
This paper describes a sequence of residual stress measurements made to determine a two-dimensional map of biaxial residual stress in a nozzle mockup having two welds, one a dissimilar metal (DM) weld and the other a stainless steel (SS) weld. The mockup is cylindrical, designed to represent a pressurizer surge nozzle of a nuclear pressurized water reactor (PWR), and was fabricated as part of a weld residual stress measurement and finite-element (FE) modeling round-robin exercise. The mockup has a nickel alloy DM weld joining an SS safe end to a low-alloy steel cylinder and stiffening ring, as well as an SS weld joining the safe end to a section of SS pipe. The biaxial mapping experiments follow an approach described earlier, in PVP2012-78885 and PVP2013-97246, and comprise a series of experimental steps and a computation to determine a two dimensional map of biaxial (axial and hoop) residual stress near the SS and DM welds. Specifically, the biaxial stresses are a combination of a contour measurement of hoop stress in the cylinder, slitting measurements of axial stress in thin slices removed from the cylinder wall, and a computation that determines the axial stress induced by measured hoop stress. At the DM weld, hoop stress is tensile near the OD (240 MPa) and compressive at the ID (-320 MPa), and axial stress is tensile near the OD (370 MPa) and compressive near the midthickness (-230 MPa) and ID (-250 MPa). At the SS weld, hoop stress is tensile near the OD (330 MPa) and compressive near the ID (-210 MPa), and axial stress is tensile at the OD (220 MPa) and compressive near midthickness (-225 MPa) and ID (-30 MPa). The measured stresses are found to be consistent with earlier work in similar configurations.
- Published
- 2016
144. Observational learning computations in neurons of the human anterior cingulate cortex
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Hill, Michael R, Boorman, Erie D, and Fried, Itzhak
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Biological Psychology ,Cognitive and Computational Psychology ,Information and Computing Sciences ,Psychology ,Machine Learning ,Basic Behavioral and Social Science ,Neurosciences ,Behavioral and Social Science ,Neurological ,Adult ,Bayes Theorem ,Brain Mapping ,Decision Making ,Female ,Gyrus Cinguli ,Humans ,Learning ,Male ,Neurons ,Observation - Abstract
When learning from direct experience, neurons in the primate brain have been shown to encode a teaching signal used by algorithms in artificial intelligence: the reward prediction error (PE)-the difference between how rewarding an event is, and how rewarding it was expected to be. However, in humans and other species learning often takes place by observing other individuals. Here, we show that, when humans observe other players in a card game, neurons in their rostral anterior cingulate cortex (rACC) encode both the expected value of an observed choice, and the PE after the outcome was revealed. Notably, during the same task neurons recorded in the amygdala (AMY) and the rostromedial prefrontal cortex (rmPFC) do not exhibit this type of encoding. Our results suggest that humans learn by observing others, at least in part through the encoding of observational PEs in single neurons in the rACC.
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- 2016
145. Measured Biaxial Residual Stress Maps in a Stainless Steel Weld
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Olson, Mitchell D, Hill, Michael R, Patel, Vipul I, Muránsky, Ondrej, and Sisneros, Thomas
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residual stress ,welding ,contour method ,computational weld modeling ,neutron diffraction ,X-ray diffraction - Abstract
This paper describes a sequence of residual stress measurements made to determine a two-dimensional map of biaxial residual stress in a stainless steel weld. A long stainless steel (316L) plate with an eight-pass groove weld (308L filler) was used. The biaxial stress measurements follow a recently developed approach, comprising a combination of contour method and slitting measurements, with a computation to determine the effects of out-of-plane stress on a thin slice. The measured longitudinal stress is highly tensile in the weld- and heat-affected zone, with a maximum around 450 MPa, and compressive stress toward the transverse edges around −250 MPa. The total transverse stress has a banded profile in the weld with highly tensile stress at the bottom of the plate (y = 0) of 400 MPa, rapidly changing to compressive stress (at y = 5 mm) of −200 MPa, then tensile stress at the weld root (y = 17 mm) and in the weld around 200 MPa, followed by compressive stress at the top of the weld at around −150 MPa. The results of the biaxial map compare well with the results of neutron diffraction measurements and output from a computational weld simulation.
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- 2015
146. Effects of Empagliflozin on Fluid Overload, Weight, and Blood Pressure in CKD
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Mayne, Kaitlin J., Staplin, Natalie, Keane, David F., Wanner, Christoph, Brenner, Susanne, Cejka, Vladimir, Stegbauer, Johannes, Judge, Parminder K., Preiss, David, Emberson, Jonathan, Trinca, Daniele, Dayanandan, Rejive, Lee, Ryonfa, Nolan, John, Omata, Akiko, Green, Jennifer B., Cherney, David Z.I., Hooi, Lai Seong, Pontremoli, Roberto, Tuttle, Katherine R., Lees, Jennifer S., Mark, Patrick B., Davies, Simon J., Hauske, Sibylle J., Steubl, Dominik, Brückmann, Martina, Landray, Martin J., Baigent, Colin, Haynes, Richard, Herrington, William G., Baigent, Colin, Landray, Martin J., Wanner, Christoph, Herrington, William G., Haynes, Richard, Green, Jennifer B., Hauske, Sibylle J., Brueckmann, Martina, Hopley, Mark, von-Eynatten, Maximillian, George, Jyothis, Brenner, Susanne, Cheung, Alfred K., Preiss, David, Liu, Zhi-Hong, Li, Jing, Hooi, Laiseong, Liu, Wen, Kadowaki, Takashi, Nangaku, Masaomi, Levin, Adeera, Cherney, David, Pontremoli, Roberto, Maggioni, Aldo P., Staplin, Natalie, Emberson, Jonathan, Hantel, Stefan, Goto, Shinya, Deo, Rajat, Tuttle, Katherine R., Hill, Michael, Judge, Parminder, Mayne, Kaitlin J., Ng, Sarah Y.A., Rossello, Xavier, Sammons, Emily, Zhu, Doreen, Sandercock, Peter, Bilous, Rudolf, Herzog, Charles, Whelton, Paul, Wittes, Janet, Bennett, Derrick, Achiri, Patricia, Ambrose, Chrissie, Badin, Cristina, Barton, Jill, Brown, Richard, Burke, Andy, Butler, Sebastian, Dayanandan, Rejive, Donaldson, Pia, Dykas, Robert, Fletcher, Lucy, Frederick, Kate, Kingston, Hannah, Gray, Mo, Harding, Emily, Hashimoto, Akiko, Howie, Lyn, Hurley, Susan, Lee, Ryonfa, Luker, Nik, Murphy, Kevin, Nakahara, Mariko, Nolan, John, Nunn, Michelle, Mulligan, Sorcha, Omata, Akiko, Pickworth, Sandra, Qiao, YanRu, Shah, Shraddha, Taylor, Karen, Timadjer, Alison, Willett, Monique, Wincott, Liz, Yan, Qin, Yu, Hui, Bowman, Louise, Chen, Fang, Clarke, Robert, Goonasekera, Michelle, Haynes, Richard, Herrington, William G., Judge, Parminder, Karsan, Waseem, Mafham, Marion, Mayne, Kaitlin J., Ng, Sarah Y. A., Preiss, David, Reith, Christina, Sammons, Emily, Zayed, Mohammed, Zhu, Doreen, Ellison, Ritva, Moys, Rowan, Stevens, Will, Verdel, Kevin, Wallendszus, Karl, Bowler, Chris, Brewer, Anna, Measor, Andy, Cui, Guanguo, Daniels, Charles, Field, Angela, Goodenough, Bob, Lawson, Ashley, Mostefai, Youcef, Radhakrishnan, Dheeptha, Syed, Samee, Xia, Shuang, Adewuyi-Dalton, Ruth, Arnold, Thomas, Beneat, Anne-Marie, Bhatt, Anoushka, Bird, Chloe, Breach, Andrew, Brown, Laura, Caple, Mark, Chavagnon, Tatyana, Chung, Karen, Clark, Sarah, Condurache, Luminita, Eichstadt, Katarzyna, Obrero, Marta Espino, Forest, Scarlett, French, Helen, Goodwin, Nick, Gordon, Andrew, Gordon, Joanne, Guest, Cat, Harding, Tina, Hill, Michael, Hozak, Michal, Lacey, Matthew, MacLean, David, Messinger, Louise, Moffat, Stewart, Radley, Martin, Shenton, Claire, Tipper, Sarah, Tyler, Jon, Weaving, Lesley, Wheeler, James, Williams, Elissa, Williams, Tim, Woodhouse, Hamish, Chamberlain, Angela, Chambers, Jo, Davies, Joanne, Donaldson, Denise, Faria-Shayler, Pati, Fleming-Brown, Denise, Ingell, Jennifer, Knott, Carol, Liew, Anna, Lochhead, Helen, Meek, Juliette, Rodriguez-Bachiller, Isabel, Wilson, Andrea, Zettergren, Patrick, AitSadi, Rach, Barton, Ian, Baxter, Alex, Bu, Yonghong, Danel, Lukasz, Grotjahn, Sonja, Kurien, Rijo, Lay, Michael, Maskill, Archie, Murawska, Aleksandra, Raff, Rachel, Young, Allen, Baigent, Colin, Haynes, Richard, Herrington, William G., Landray, Martin J., Preiss, David, Emberson, Jonathan, Sardell, Rebecca, Staplin, Natalie, Wanner, Christoph, Brenner, Susanne, Cejka, Vladimir, Fajardo-Moser, Marcela, Hartner, Christian, Poehler, Doris, Renner, Janina, Scheidemantel, Franziska, Haynes, Richard, Preiss, David, Herrington, William G., Judge, Parminder, Zhu, Doreen, Ng, Sarah Y. A., Mayne, Kaitlin J., Badin, Cristina, Chambers, Jo, Davies, Joanne, Donaldson, Denise, Gray, Mo, Harding, Emily, Ingell, Jenny, Qiao, Yanru, Shah, Shraddha, Wilson, Andrea, Zettergren, Patrick, Wanner, Christoph, Brenner, Susanne, Cejka, Vladimir, Ghavampour, Sharang, Knoppe, Anja, Schmidt-Gurtler, Hans, Dumann, Hubert, Merscher, Sybille, Patecki, Margret, Schlieper, Georg Rainer, Torp, Anke, Weber, Bianca, Zietz, Maja, Sitter, Thomas, Fuessl, Louise, Krappe, Julia, Loutan, Jerome, Vielhauer, Volker, Andriaccio, Luciano, Maurer, Magdalena, Winkelmann, Bernhard, Dursch, Martin, Seifert, Linda, Tenbusch, Linda, Weinmann-Menke, Julia, Boedecker, Simone, KaluzaSchilling, Wiebke, Kraus, Daniel, Krieger, Carina, Schmude, Margit, Schreiber, Anne, Eckrich, Ewelina, Tschope, Diethelm, Arbi, Abdulwahab, Lee-Barkey, Young, Stratmann, Bernd, Prib, Natalie, Rolfsmeier, Sina, Schneider, Irina, Rump, Lars, Stegbauer, Johannes, Pötz, Christine, Schemmelmann, Mara, Schmidt, Claudia, Haller, Hermann, Kaufeld, Jessica, Menne, Jan, Bahlmann-Kroll, Elisabeth, Bergner, Angela, Haynes, Richard, Herrington, William G., Zhu, Doreen, Gavrila, Madita, Lafferty, Kathryn, Rabara, Ria, Ruse, Sally, Weetman, Maria, Byrne, Cath, Jesky, Mark, Cowley, Alison, McHaffie, Emma, Waterfall, Holly, Taylor, Jo, Bough, Laura, Phillips, Thomas, Goodwin, Barbara Winter-, Frankel, Andrew, Tomlinson, James, Alegata, Marlon, Almasarwah, Rashid, Apostolidi, Anthoula, Vourvou, Maria, Walters, Thomas, Ugni, Shiva, Gunda, Smita, Oluyombo, Rotimi, Brindle, Vicki, Coutts, Ping, Fuller, Tracy, Nadar, Evelyn, Wong, Christopher, Goldsmith, Christopher, Barnes, Sherald, Bennett, Ann, Burston, Claire, Hope, Samantha, Hunt, Nicola, Kurian, Lini, Fish, Richard, Farrugia, Daniela, Lee, Judy, Sadler, Emma, Turner, Hannah, Clarke, Helen, Carnall, Victoria, Benyon, Sarah, Blake, Caroline, Estcourt, Stephanie, Piper, Jane, Morgan, Neal, Hutchinson, Carolyn, McKinley, Teresa, Doulton, Tim, Delaney, Michael, Montasser, Mahmoud, Hansen, Jenny, Loader, David, Moon, Angela, Morris, Frances, Fraser, Donald, Ali, Mohammad Alhadj, Griffin, Sian, Latif, Farah, Witczak, Justyna, Wonnacott, Alexa, Jeffers, Lynda, Webley, Yvette, Bell, Samira, Cosgrove, Leanne, Craik, Rachel, Murray, Shona, Khwaja, Arif, Jackson, Yvonne, Mbuyisa, Angeline, Sellars, Rachel, Lewington, Andrew, Baker, Richard, Dorey, Suzannah, Tobin, Kay, Wheatley, Rosalyn, Patel, Rajan, Mark, Patrick, Rankin, Alastair, Sullivan, Michael, Forsyth, Kirsty, and McDougall, Rowan
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- 2024
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147. Topological modular forms with level structure
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Hill, Michael and Lawson, Tyler
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Mathematics - Algebraic Topology ,Mathematics - Number Theory ,55N34 (primary), 55P43, 11F23, 11G18, 14F20 (secondary) - Abstract
The cohomology theory known as Tmf, for "topological modular forms," is a universal object mapping out to elliptic cohomology theories, and its coefficient ring is closely connected to the classical ring of modular forms. We extend this to a functorial family of objects corresponding to elliptic curves with level structure and modular forms on them. Along the way, we produce a natural way to restrict to the cusps, providing multiplicative maps from Tmf with level structure to forms of K-theory. In particular, this allows us to construct a connective spectrum tmf_0(3) consistent with properties suggested by Mahowald and Rezk. This is accomplished using the machinery of logarithmic structures. We construct a sheaf of locally even-periodic elliptic cohomology theories, equipped with highly structured multiplication, on the log-\'etale site of the moduli of elliptic curves. Evaluating this sheaf on modular curves produces Tmf with level structure., Comment: 53 pages. Heavily revised, including the addition of a new section on background tools from homotopy theory
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- 2013
148. Ten ways to improve academic CVs for fairer research assessment
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Strinzel, Michaela, Brown, Josh, Kaltenbrunner, Wolfgang, de Rijcke, Sarah, and Hill, Michael
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- 2021
- Full Text
- View/download PDF
149. The Brain in Motion II Study: study protocol for a randomized controlled trial of an aerobic exercise intervention for older adults at increased risk of dementia
- Author
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Krüger, Renata L., Clark, Cameron M., Dyck, Adrienna M., Anderson, Todd J., Clement, Fiona, Hanly, Patrick J., Hanson, Heather M., Hill, Michael D., Hogan, David B., Holroyd-Leduc, Jayna, Longman, R. Stewart, McDonough, Meghan, Pike, G. Bruce, Rawling, Jean M., Sajobi, Tolulope, and Poulin, Marc J.
- Published
- 2021
- Full Text
- View/download PDF
150. Role of RAGE in obesity-induced adipose tissue inflammation and insulin resistance
- Author
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Feng, Ziqian, Du, Zuoqin, Shu, Xin, Zhu, Luochen, Wu, Jiaqi, Gao, Qian, Wang, Liqun, Chen, Ni, Li, Yi, Luo, Mao, Hill, Michael A., and Wu, Jianbo
- Published
- 2021
- Full Text
- View/download PDF
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