1,355 research outputs found
Gravitational Dynamics From Entanglement "Thermodynamics"
In a general conformal field theory, perturbations to the vacuum state obey
the relation \delta S = \delta E, where \delta S is the change in entanglement
entropy of an arbitrary ball-shaped region, and \delta E is the change in
"hyperbolic" energy of this region. In this note, we show that for holographic
conformal field theories, this relation, together with the holographic
connection between entanglement entropies and areas of extremal surfaces and
the standard connection between the field theory stress tensor and the boundary
behavior of the metric, implies that geometry dual to the perturbed state
satisfies Einstein's equations expanded to linear order about pure AdS.Comment: v2: references added, problematic section on Radon transform remove
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PD-1 as a potential target in cancer therapy
Recently, an improved understanding of the molecular mechanisms governing the host response to tumors has led to the identification of checkpoint signaling pathways involved in limiting the anticancer immune response. One of the most critical checkpoint pathways responsible for mediating tumor-induced immune suppression is the programmed death-1 (PD-1) pathway, normally involved in promoting tolerance and preventing tissue damage in settings of chronic inflammation. Many human solid tumors express PD ligand 1 (PD-L1), and this is often associated with a worse prognosis. Tumor-infiltrating lymphocytes from patients with cancer typically express PD-1 and have impaired antitumor functionality. Proof-of-concept has come from several preclinical studies in which blockade of PD-1 or PD-L1 enhanced T-cell function and tumor cell lysis. Three monoclonal antibodies against PD-1, and one against PD-L1, have reported phase 1 data. All four agents have shown encouraging preliminary activity, and those that have been evaluated in larger patient populations appear to have encouraging safety profiles. Additional data are eagerly awaited. This review summarizes emerging clinical data and potential of PD-1 pathway–targeted antibodies in development. If subsequent investigations confirm the initial results, it is conceivable that agents blocking the PD-1/PD-L1 pathway will prove valuable additions to the growing armamentarium of targeted immunotherapeutic agents. Next-generation immunotherapy agents that target the PD-1 checkpoint pathway are demonstrating antitumor activity and encouraging safety profiles in early clinical trials. Current and future clinical trials will provide new insights, and the evaluation of biomarkers and rational combination therapies is ongoing
NOD-like receptors and inflammation
The nucleotide-binding and oligomerization domain, leucine-rich repeat (also known as NOD-like receptors, both abbreviated to NLR) family of intracellular pathogen recognition receptors are increasingly being recognized to play a pivotal role in the pathogenesis of a number of rare monogenic diseases, as well as some more common polygenic conditions. Bacterial wall constituents and other cellular stressor molecules are recognized by a range of NLRs, which leads to activation of the innate immune response and upregulation of key proinflammatory pathways, such as IL-1β production and translocation of nuclear factor-κB to the nucleus. These signalling pathways are increasingly being targeted as potential sites for new therapies. This review discusses the role played by NLRs in a variety of inflammatory diseases and describes the remarkable success to date of these therapeutic agents in treating some of the disorders associated with aberrant NLR function
Chest pain without obstructive coronary artery disease: a case series report
Background:
Ischaemic heart disease is a leading cause of mortality in women. Even in those without obstructive coronary artery disease (CAD), women with angina continue to have increased mortality. There are gender differences in prevalence of different pathophysiologies, including functional disorders such as microvascular and vasospastic angina.
Case summary:
We describe four cases of angina in women with no obstructive CAD, in whom coronary function testing was performed. These four patients were diagnosed with disorders of coronary vasomotion, including vasospastic angina and different endotypes of microvascular angina.
Discussion:
This case series highlights the different mechanisms of ischaemia in the absence of obstructive CAD. Patients with angina and no obstructive CAD classified by computed tomography coronary angiography may have myocardial ischaemia due to microvascular angina, vasospastic angina, or both. Conventional investigations risk under-diagnosing, and as a consequence under-treating, patients with these conditions. Coronary function testing, in the form of diagnostic guidewire-based tests and adjunctive acetylcholine provocation, has proven to be critical in the accurate diagnoses and appropriate management of these patients
Computational Bounds for Doing Harmonic Analysis on Permutation Modules of Finite Groups
We develop an approach to finding upper bounds for the number of arithmetic
operations necessary for doing harmonic analysis on permutation modules of
finite groups. The approach takes advantage of the intrinsic orbital structure
of permutation modules, and it uses the multiplicities of irreducible
submodules within individual orbital spaces to express the resulting
computational bounds. We conclude by showing that these bounds are surprisingly
small when dealing with certain permutation modules arising from the action of
the symmetric group on tabloids.Comment: 19 page
Understanding and Affecting Student Reasoning About Sound Waves
Student learning of sound waves can be helped through the creation of
group-learning classroom materials whose development and design rely on
explicit investigations into student understanding. We describe reasoning in
terms of sets of resources, i.e. grouped building blocks of thinking that are
commonly used in many different settings. Students in our university physics
classes often used sets of resources that were different from the ones we wish
them to use. By designing curriculum materials that ask students to think about
the physics from a different view, we bring about improvement in student
understanding of sound waves. Our curriculum modifications are specific to our
own classes, but our description of student learning is more generally useful
for teachers. We describe how students can use multiple sets of resources in
their thinking, and raise questions that should be considered by both
instructors and researchers.Comment: 23 pages, 4 figures, 3 tables, 28 references, 7 notes. Accepted for
publication in the International Journal of Science Educatio
Clinical Benefits of the Dermabond Prineo Skin Closure System for Total Hip and Knee Arthroplasty Compared to Skin Staples
Momentum-space entanglement and renormalization in quantum field theory
The degrees of freedom of any interacting quantum field theory are entangled
in momentum space. Thus, in the vacuum state, the infrared degrees of freedom
are described by a density matrix with an entanglement entropy. We derive a
relation between this density matrix and the conventional Wilsonian effective
action. We argue that the entanglement entropy of and mutual information
between subsets of field theoretic degrees of freedom at different momentum
scales are natural observables in quantum field theory and demonstrate how to
compute these in perturbation theory. The results may be understood
heuristically based on the scale-dependence of the coupling strength and number
of degrees of freedom. We measure the rate at which entanglement between
degrees of freedom declines as their scales separate and suggest that this
decay is related to the property of decoupling in quantum field theory.Comment: 31 pages, LaTeX, 6 figure
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