Quantum walks: a comprehensive review

Quantum walks, the quantum mechanical counterpart of classical random walks, is an advanced tool for building quantum algorithms that has been recently shown to constitute a universal model of quantum computation. Quantum walks is now a solid field of research of quantum computation full of exciting open problems for physicists, computer scientists, mathematicians and engineers. In this paper we review theoretical advances on the foundations of both discrete- and continuous-time quantum walks, together with the role that randomness plays in quantum walks, the connections between the mathematical models of coined discrete quantum walks and continuous quantum walks, the quantumness of quantum walks, a summary of papers published on discrete quantum walks and entanglement as well as a succinct review of experimental proposals and realizations of discrete-time quantum walks. Furthermore, we have reviewed several algorithms based on both discrete- and continuous-time quantum walks as well as a most important result: the computational universality of both continuous- and discrete- time quantum walks.Comment: Paper accepted for publication in Quantum Information Processing Journa

Plasmid-Encoded Proinsulin Preserves C-Peptide While Specifically Reducing Proinsulin-Specific CD8+ T Cells in Type 1 Diabetes

In type 1 diabetes (T1D) an intense inflammatory response destroys β cells in the pancreas, where insulin is produced and released. A therapy for T1D that reduces the specific autoimmune response in this disease while leaving the remainder of the immune system intact has long been sought. Proinsulin is a major target of adaptive immunity in T1D. We hypothesized that an engineered DNA plasmid encoding proinsulin (BHT-3021) would preserve β cell function in T1D patients through reduction of insulin-specific T cells. We studied 80 subjects over 18 years of age who were diagnosed with T1D within 5 years. Subjects were randomized 2:1 to receive intramuscular injections of BHT-3021 or BHT-placebo, weekly for 12 weeks, and then monitored for safety and immune responses in a blinded fashion. Four dose levels of BHT-3021 were evaluated: 0.3, 1.0, 3.0, and 6.0 mg. C-peptide served as an exploratory measure of efficacy and safety. Islet-specific CD8+ T cell frequencies were assessed with multimers of monomeric human leukocyte antigen class I molecules loaded with peptides containing pancreatic or unrelated antigens. No serious adverse events related to BHT-3021 occurred. C-peptide levels improved relative to placebo at all doses, most notably at 1 mg at 15 weeks (+19.5% BHT-3021 versus −8.8% BHT-placebo, P < 0.026). Proinsulin-reactive CD8+ T cells, but not T cells against unrelated islet or foreign molecules, declined in the BHT-3021 arm (P < 0.006). Thus, we demonstrate that a plasmid encoding proinsulin reduces the frequency of CD8+ T cells reactive to proinsulin while preserving C-peptide over the course of dosing

Entropy Stable Finite Volume Approximations for Ideal Magnetohydrodynamics

This article serves as a summary outlining the mathematical entropy analysis of the ideal magnetohydrodynamic (MHD) equations. We select the ideal MHD equations as they are particularly useful for mathematically modeling a wide variety of magnetized fluids. In order to be self-contained we first motivate the physical properties of a magnetic fluid and how it should behave under the laws of thermodynamics. Next, we introduce a mathematical model built from hyperbolic partial differential equations (PDEs) that translate physical laws into mathematical equations. After an overview of the continuous analysis, we thoroughly describe the derivation of a numerical approximation of the ideal MHD system that remains consistent to the continuous thermodynamic principles. The derivation of the method and the theorems contained within serve as the bulk of the review article. We demonstrate that the derived numerical approximation retains the correct entropic properties of the continuous model and show its applicability to a variety of standard numerical test cases for MHD schemes. We close with our conclusions and a brief discussion on future work in the area of entropy consistent numerical methods and the modeling of plasmas

Horizons unlimited

CONTEXT: Recent studies have implicated proinflammatory responses in the mechanism of type 1 diabetes (T1D). OBJECTIVE: Our objective was to evaluate the safety and effects of therapy with the anti-inflammatory serum protein alpha1-antitrypsin (AAT) on islet function and innate immunity in recent-onset patients. DESIGN AND SETTING: This was an open-label phase I trial at the Barbara Davis Center for Childhood Diabetes, University of Colorado Denver. PATIENTS: Twelve recently diagnosed subjects with T1D with detectable C-peptides were included in the study. INTERVENTION: Eight consecutive weekly infusions of 80 mg/kg of AAT were given. MAIN OUTCOME MEASURES: PATIENTS were monitored for adverse effects of AAT therapy, C-peptide responses to a mixed-meal tolerance test, and toll-like receptor (TLR)-induced cellular IL-1beta in monocytes and myeloid dendritic cells (mDCs). RESULTS: No adverse effects were detected. AAT led to increased, unchanged, or moderately reduced levels of C-peptide responses compared with baseline in 5 patients. The total content of TLR4-induced cellular IL-1beta in monocytes at 12 months after AAT therapy was 3-fold reduced compared with baseline (P < .05). Furthermore, at baseline, 82% of monocytes produced IL-1beta, but at 12 months after therapy, the level decreased to 42%. Similar reductions were observed using TLR7/8 and TLR3 agonists in monocytes and mDCs. Unexpectedly, the reduction in cellular IL-1beta was observed only 9 and 12 months after treatment but not in untreated diabetics. Improved beta-cell function in the 5 AAT-treated individuals correlated with lower frequencies of monocytes and mDCs producing IL-1beta compared with subjects without improvement of islet function (P < .04 and P < .02, respectively). CONCLUSIONS: We hypothesize that AAT may have a beneficial effect on T1D in recently diagnosed patients that is associated with downmodulation of IL-1beta

Structure-Based Selection of Small Molecules To Alter Allele-Specific MHC Class II Antigen Presentation

Transplantation and autoimmunit

Understanding and preventing type 1 diabetes through the unique working model of TrialNet (Pg 2139, Vol 60, 2017)

Transplantation and autoimmunit

Islet-Derived CD4 T Cells Targeting Proinsulin in Human Autoimmune Diabetes

Transplantation and autoimmunit