httk: R Package for High-Throughput Toxicokinetics

Thousands of chemicals have been profiled by high-throughput screening programs such as ToxCast and Tox21; these chemicals are tested in part because most of them have limited or no data on hazard, exposure, or toxicokinetics. Toxicokinetic models aid in predicting tissue concentrations resulting from chemical exposure, and a "reverse dosimetry" approach can be used to predict exposure doses sufficient to cause tissue concentrations that have been identified as bioactive by high-throughput screening. We have created four toxicokinetic models within the R software package httk. These models are designed to be parameterized using high-throughput in vitro data (plasma protein binding and hepatic clearance), as well as structure-derived physicochemical properties and species-specific physiological data. The package contains tools for Monte Carlo sampling and reverse dosimetry along with functions for the analysis of concentration vs. time simulations. The package can currently use human in vitro data to make predictions for 553 chemicals in humans, rats, mice, dogs, and rabbits, including 94 pharmaceuticals and 415 ToxCast chemicals. For 67 of these chemicals, the package includes rat-specific in vitro data. This package is structured to be augmented with additional chemical data as they become available. Package httk enables the inclusion of toxicokinetics in the statistical analysis of chemicals undergoing high-throughput screening

On higher congruences between cusp forms and Eisenstein series

In this paper we present several finite families of congruences between cusp forms and Eisenstein series of higher weights at powers of prime ideals. We formulate a conjecture which describes properties of the prime ideals and their relation to the weights. We check the validity of the conjecture on several numerical examples.Comment: 20 page

Magnetic-Field-Driven Superconductor-Insulator-Type Transition in Graphite

A magnetic-field-driven transition from metallic- to semiconducting-type behavior in the basal-plane resistance takes place in highly oriented pyrolytic graphite at a field $H_c \sim 1~$kOe applied along the hexagonal c-axis. The analysis of the data reveals a striking similarity between this transition and that measured in thin-film superconductors and Si MOSFET's. However, in contrast to those materials, the transition in graphite is observable at almost two orders of magnitude higher temperatures.Comment: 4 Figure

The final publication is available at link.springer.com. An Optimal Control Approach to Find Sparse Data for Laplace Interpolation

Abstract. Finding optimal data for inpainting is a key problem in the context of partial differential equation-based image compression. We present a new model for optimising the data used for the reconstruction by the underlying homogeneous diffusion process. Our approach is based on an optimal control framework with a strictly convex cost functional containing an L1 term to enforce sparsity of the data and non-convex constraints. We propose a numerical approach that solves a series of convex optimisation problems with linear constraints. Our numerical examples show that it outperforms existing methods with respect to quality and computation time

A combined first and second order variational approach for image reconstruction

In this paper we study a variational problem in the space of functions of bounded Hessian. Our model constitutes a straightforward higher-order extension of the well known ROF functional (total variation minimisation) to which we add a non-smooth second order regulariser. It combines convex functions of the total variation and the total variation of the first derivatives. In what follows, we prove existence and uniqueness of minimisers of the combined model and present the numerical solution of the corresponding discretised problem by employing the split Bregman method. The paper is furnished with applications of our model to image denoising, deblurring as well as image inpainting. The obtained numerical results are compared with results obtained from total generalised variation (TGV), infimal convolution and Euler's elastica, three other state of the art higher-order models. The numerical discussion confirms that the proposed higher-order model competes with models of its kind in avoiding the creation of undesirable artifacts and blocky-like structures in the reconstructed images -- a known disadvantage of the ROF model -- while being simple and efficiently numerically solvable.Comment: 34 pages, 89 figure

Microscope and microâ camera assessment of Schneiderian membrane perforation via transcrestal sinus floor elevation: A randomized ex vivo study

ObjectiveWe sought to assess the effectiveness of using a microscope and nonâ invasive camera for assessing sinus membrane perforations during transcrestal sinus floor elevation (TSFE).Materials and methodsFive fresh human cadaver heads corresponding to eight maxillary sinuses (six bilateral and two unilateral) underwent 4 TSFEs per sinus (a total of 32 single site elevations). Each elevation was randomly assigned to receive a three or six mm membrane elevation height (MEH). A microscope and microâ camera were used to assess the sinus membrane perforation. Afterwards, radiological and clinical membrane perforation assessments were performed. The statistical analysis results are expressed using the means, standard deviations, range values of the residual ridge height (RRH), residual ridge width (RRW), sinus membrane thickness (SMT) and incidence of perforation (IoP). Generalized linear methods were used to test for the correlation of RRH and MEH to the microscope and microâ camera perforation assessments and the correlation of microscope and microâ camera assessments with the postâ operative CBCT and crestal liquid evaluation.ResultsThe cumulative percentage of IoP was 40.62%, (23.07% with 3 mm MEH, and 76.92% with 6 mm MEH, p < 0.05). The perforation assessed using either the microscope or microâ camera coincided with the postâ operative CBCT and crestal liquid assessment in 87.55% sites. No significant correlation was found between the microscope or microâ camera assessments with RRH or MEH.ConclusionApplication of a microscope and microâ camera during transcrestal sinus floor elevation may allow the detection of the integrity of the Schneiderian membrane with greater than 85% accuracy in this ex vivo model.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149727/1/clr13453.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149727/2/clr13453_am.pd

When Anomaly Mediation is UV Sensitive

Despite its successes---such as solving the supersymmetric flavor problem---anomaly mediated supersymmetry breaking is untenable because of its prediction of tachyonic sleptons. An appealing solution to this problem was proposed by Pomarol and Rattazzi where a threshold controlled by a light field deflects the anomaly mediated supersymmetry breaking trajectory, thus evading tachyonic sleptons. In this paper we examine an alternate class of deflection models where the non-supersymmetric threshold is accompanied by a heavy, instead of light, singlet. The low energy form of this model is the so-called extended anomaly mediation proposed by Nelson and Weiner, but with potential for a much higher deflection threshold. The existence of this high deflection threshold implies that the space of anomaly mediated supersymmetry breaking deflecting models is larger than previously thought.Comment: 14 pages, 1 figure (version to appear in JHEP

Medicinal plants used in the treatment of human immunodeficiency virus

Since the beginning of the epidemic, human immunodeficiency virus (HIV) has infected around 70 million people worldwide, most of whom reside is sub-Saharan Africa. There have been very promising developments in the treatment of HIV with anti-retroviral drug cocktails. However, drug resistance to anti-HIV drugs is emerging, and many people infected with HIV have adverse reactions or do not have ready access to currently available HIV chemotherapies. Thus, there is a need to discover new anti-HIV agents to supplement our current arsenal of anti-HIV drugs and to provide therapeutic options for populations with limited resources or access to currently efficacious chemotherapies. Plant-derived natural products continue to serve as a reservoir for the discovery of new medicines, including anti-HIV agents. This review presents a survey of plants that have shown anti-HIV activity, both in vitro and in vivo