A Finite Element Analysis of Orthodontic Single Buccal Tube with Hook, on Molar Tooth Movement

Buccal tubes are usually attached to the molar bands during orthodontics fixed appliance therapy. The molar tooth provides area of anchorage and forces are applied from the buccal tube hook. The hook is positioned in the mesial part of the tube, and force is applied (minimum 50 grams to maximum 150 grams) on hook. Because of the applied force on hook, there is a reactive change in molar position in the form of translation. The aim of this work is to show the molar tooth mesial translation for the applied force on the buccal tube hook

Symmetry Breaking in the Congest Model:Time- and Message-Efficient Algorithms for Ruling Sets

We study local symmetry breaking problems in the CONGEST model, focusing on ruling set problems, which generalize the fundamental Maximal Independent Set (MIS) problem. A $\beta$-ruling set is an independent set such that every node in the graph is at most $\beta$ hops from a node in the independent set. Our work is motivated by the following central question: can we break the $\Theta(\log n)$ time complexity barrier and the $\Theta(m)$ message complexity barrier in the CONGEST model for MIS or closely-related symmetry breaking problems? We present the following results: - Time Complexity: We show that we can break the $O(\log n)$ "barrier" for 2- and 3-ruling sets. We compute 3-ruling sets in $O\left(\frac{\log n}{\log \log n}\right)$ rounds with high probability (whp). More generally we show that 2-ruling sets can be computed in $O\left(\log \Delta \cdot (\log n)^{1/2 + \varepsilon} + \frac{\log n}{\log\log n}\right)$ rounds for any $\varepsilon > 0$, which is $o(\log n)$ for a wide range of $\Delta$ values (e.g., $\Delta = 2^{(\log n)^{1/2-\varepsilon}}$). These are the first 2- and 3-ruling set algorithms to improve over the $O(\log n)$-round complexity of Luby's algorithm in the CONGEST model. - Message Complexity: We show an $\Omega(n^2)$ lower bound on the message complexity of computing an MIS (i.e., 1-ruling set) which holds also for randomized algorithms and present a contrast to this by showing a randomized algorithm for 2-ruling sets that, whp, uses only $O(n \log^2 n)$ messages and runs in $O(\Delta \log n)$ rounds. This is the first message-efficient algorithm known for ruling sets, which has message complexity nearly linear in $n$ (which is optimal up to a polylogarithmic factor)

The Message Complexity of Distributed Graph Optimization

The message complexity of a distributed algorithm is the total number of messages sent by all nodes over the course of the algorithm. This paper studies the message complexity of distributed algorithms for fundamental graph optimization problems. We focus on four classical graph optimization problems: Maximum Matching (MaxM), Minimum Vertex Cover (MVC), Minimum Dominating Set (MDS), and Maximum Independent Set (MaxIS). In the sequential setting, these problems are representative of a wide spectrum of hardness of approximation. While there has been some progress in understanding the round complexity of distributed algorithms (for both exact and approximate versions) for these problems, much less is known about their message complexity and its relation with the quality of approximation. We almost fully quantify the message complexity of distributed graph optimization by showing the following results...[see paper for full abstract

Two-dimensional ranking of Wikipedia articles

The Library of Babel, described by Jorge Luis Borges, stores an enormous amount of information. The Library exists {\it ab aeterno}. Wikipedia, a free online encyclopaedia, becomes a modern analogue of such a Library. Information retrieval and ranking of Wikipedia articles become the challenge of modern society. While PageRank highlights very well known nodes with many ingoing links, CheiRank highlights very communicative nodes with many outgoing links. In this way the ranking becomes two-dimensional. Using CheiRank and PageRank we analyze the properties of two-dimensional ranking of all Wikipedia English articles and show that it gives their reliable classification with rich and nontrivial features. Detailed studies are done for countries, universities, personalities, physicists, chess players, Dow-Jones companies and other categories.Comment: RevTex 9 pages, data, discussion added, more data at http://www.quantware.ups-tlse.fr/QWLIB/2drankwikipedia

Mapping of Hydraulic Fractures Using Tiltmeter Data for Design of EGS Stimulation

ABSTRACT Tiltmeters are widely used in the monitoring of hydraulic fractures, a procedure wherein reservoir rock formations are fractured by the injection of pressurized fluid to enhance well productivity. Tiltmeters measure the fracture induced deformations which can then be inverted to obtain useful fracture parameters. Hydraulic fracturing is now being proposed for stimulation of enhanced geothermal systems in low permeability rock for increased energy extraction. Small scale field sites are proposed as a method to obtain data on the effect of placing multiple hydraulic fractures in an injection well and connecting them to a production well. Fracture growth parameters obtained from tiltmeter mappings at such experiment sites can be used to study the effectiveness of such stimulations. In this work, we propose an approach for the inversion of tilt data using the displacement discontinuity method and the extended Kalman filter. The salient feature of the proposed method is its ability to predict fracture asymmetry with respect to the injection borehole, which is important to know to determine if each stimulation in an array has progressed as expected. This approach uses a forward model based on the analytical solution for computing the displacements and tilts due to a point source displacement discontinuity in an elastic half-space which was developed by Okad

Time evolution of Wikipedia network ranking

We study the time evolution of ranking and spectral properties of the Google matrix of English Wikipedia hyperlink network during years 2003 - 2011. The statistical properties of ranking of Wikipedia articles via PageRank and CheiRank probabilities, as well as the matrix spectrum, are shown to be stabilized for 2007 - 2011. A special emphasis is done on ranking of Wikipedia personalities and universities. We show that PageRank selection is dominated by politicians while 2DRank, which combines PageRank and CheiRank, gives more accent on personalities of arts. The Wikipedia PageRank of universities recovers 80 percents of top universities of Shanghai ranking during the considered time period.Comment: 10 pages, 11 figures. Accepted for publication in EPJ

NOX4 inhibition potentiates immunotherapy by overcoming cancer-associated fibroblast-mediated CD8 T-cell exclusion from tumours

Determining mechanisms of resistance to PD-1/PD-L1 immune checkpoint immunotherapy is key to developing new treatment strategies. Cancer-associated fibroblasts (CAF) have many tumor-promoting functions and promote immune evasion through multiple mechanisms, but as yet, there are no CAF-specific inhibitors clinically available. Here we generated CAF-rich murine tumor models (TC1, MC38, 4T1) to investigate how CAF influence the immune microenvironment and affect response to different immunotherapy modalities (anti-cancer vaccination; TC1, [HPV E7 DNA vaccine];PD-1, MC38) and found that CAFs broadly suppressed response by specifically excluding CD8+ T-cells from tumors (not CD4+ T-cells or macrophages); CD8+ T-cell exclusion was similarly present in CAF-rich human tumors. RNA sequencing of CD8+ T-cells from CAF-rich murine tumors and immunochemistry analysis of human tumors identified significant upregulation of CTLA-4 in the absence of other exhaustion markers; inhibiting CTLA-4 with a non-depleting antibody overcame the CD8+ T-cell exclusion effect without affecting T-regs. We then examined the potential for CAF targeting, focusing on the ROS-producing enzyme NOX4, which is upregulated by CAF in many human cancers, and compared this to TGF-062;1 inhibition, a key regulator of the CAF phenotype. siRNA knockdown or pharmacological inhibition (GKT137831 [Setanaxib]) of NOX4 'normalized' CAF to a quiescent phenotype and promoted intratumoral CD8+T-cell infiltration, overcoming the exclusion effect; TGF-062;1 inhibition could prevent, but not reverse, CAF differentiation. Finally, NOX4 inhibition restored immunotherapy response in CAF-rich tumors. These findings demonstrate that CAF-mediated immunotherapy resistance can be effectively overcome through NOX4 inhibition, and could improve outcome in a broad range of cancers

CryoEM reveals how the complement membrane attack complex ruptures lipid bilayers

The membrane attack complex (MAC) is one of the immune system’s first responders. Complement proteins assemble on target membranes to form pores that lyse pathogens and impact tissue homeostasis of self-cells. How MAC disrupts the membrane barrier remains unclear. Here we use electron cryo-microscopy and flicker spectroscopy to show that MAC interacts with lipid bilayers in two distinct ways. Whereas C6 and C7 associate with the outer leaflet and reduce the energy for membrane bending, C8 and C9 traverse the bilayer increasing membrane rigidity. CryoEM reconstructions reveal plasticity of the MAC pore and demonstrate how C5b6 acts as a platform, directing assembly of a giant β-barrel whose structure is supported by a glycan scaffold. Our work provides a structural basis for understanding how β-pore forming proteins breach the membrane and reveals a mechanism for how MAC kills pathogens and regulates cell functions