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Animals bearing malignant grafts reject normal grafts that express through gene transfer the same antigen.
Breaking the state of immunological unresponsiveness of tumor-bearing individuals to cancer is a prerequisite for active or passive tumor-specific immunotherapy. To study this problem the immunogenic MHC class I antigen, K216 was transfected into a progressor tumor. The transfected tumors were regularly rejected by normal mice but grew progressively in mice bearing nontransfected tumors. In addition, transgenic mice were derived to obtain normal cells and tissues expressing the same K216 gene product. Normal mice rejected K216-positive normal or malignant tissue grafts and generated K216-specific CTL in vitro and in vivo in response to these challenges. In contrast, mice bearing nontransfected tumors, though rejecting K216-positive nonmalignant tissue grafts, did not reject K216-positive tumors nor generate K216-specific CTL in response to K216-positive tumor cells. Mice bearing K216-positive tumors also rejected the nonmalignant K216-positive tissue grafts, but this in vivo response failed to lead to rejection of the simultaneously present tumor graft expressing the same antigen; in fact, immunity had no measurable effect whatsoever on tumor size or incidence and caused no selection for antigen loss variants. Taken together, the present findings suggest that transfer of expression of a target antigen into nonmalignant cells provides a way for obtaining effective stimulation of antigen-specific CTL in tumor-bearing mice, but that additional manipulations will be required to cause immunological rejection of established tumors
Proposed shunt rounding technique for large-scale security constrained loss minimization
The official published version can be obtained from the link below - Copyright @ 2010 IEEE.Optimal reactive power flow applications often model large numbers of discrete shunt devices as continuous variables, which are rounded to their nearest discrete value at the final iteration. This can degrade optimality. This paper presents novel methods based on probabilistic and adaptive threshold approaches that can extend existing security constrained optimal reactive power flow methods to effectively solve large-scale network problems involving discrete shunt devices. Loss reduction solutions from the proposed techniques were compared to solutions from the mixed integer nonlinear mathematical programming algorithm (MINLP) using modified IEEE standard networks up to 118 buses. The proposed techniques were also applied to practical large-scale network models of Great Britain. The results show that the proposed techniques can achieve improved loss minimization solutions when compared to the standard rounding method.This work was supported in part by the National Grid and in part by the EPSRC. Paper no. TPWRS-00653-2009
(1S)-1-phenylethanaminium 4-{[(1S,2S)-1-hydroxy-2,3-dihydro-1H,1'H-[2,2'-biinden]-2-yl]methyl}benzoate
Copyright 2012 © International Union of Crystallography.The title molecular salt, C8H12N+·C26H21O3-, contains a dimeric indane pharmacophore that demonstrates potent anti-inflammatory activity. The indane group of the anion exhibits some disorder about the [alpha]-C atom, which appears common to many structures containing this group. A model to account for the slight disorder was attempted, but this was deemed unsuccessful because applying bond-length constraints to all the bonds about the [alpha]-C atom led to instability in the refinement. The absolute configuration was determined crystallographically as S,S,S by anomalous dispersion methods with reference to both the Flack parameter and Bayesian statistics on Bijvoet differences. The configuration was also determined by an a priori knowledge of the absolute configuration of the (1S)-1-phenylethanaminium counter-ion. The molecules pack in the crystal structure to form an infinite two-dimensional hydrogen-bond network in the (100) plane of the unit cell
MOND and Cosmology
I review various ideas on MOND cosmology and structure formation beginning
with non-relativistic models in analogy with Newtonian cosmology. I discuss
relativistic MOND cosmology in the context of Bekenstein's theory and propose
an alternative biscalar effective theory of MOND in which the acceleration
parameter is identified with the cosmic time derivative of a matter coupling
scalar field. Cosmic CDM appears in this theory as scalar field oscillations of
the auxiliary "coupling strength" field.Comment: 8 pages, LaTeX, 2 figures, to appear in proceedings of IAP05 in
Paris: Mass Profiles and Shapes of Cosmological Structures, G. Mamon, F.
Combes, C. Deffayet and B. Fort (eds), (EDP-Sciences 2005
Substance use disorder and posttraumatic stress disorder symptomology on behavioral outcomes among juvenile justice youth
BACKGROUND AND OBJECTIVES:
Substance use behaviors have been identified as a risk factor that places juveniles at greater risk for engaging in delinquent behaviors and continual contact with the juvenile justice system. Currently, there is lack of research that explores comorbid factors associated with substance use, such as post-traumatic stress disorder (PTSD) symptoms, that could help identify youth who are at greatest risk. The aim of the present study was to examine if PTSD symptomology moderated the relationship between substance use disorder (SUD) symptoms and externalizing behaviors and commission of a violent crime; hypothesizing that risk would be heightened among youth with elevated SUD and PTSD symptomology compared to those with elevated SUD symptoms but lower PTSD symptoms.
METHOD:
The study included 194 predominantly male (78.4%), non-White (74.2%) juvenile justice youth between the ages of 9-18 (M = 15.36). Youth provided responses to assess PTSD symptoms, SUD symptoms, and externalizing behaviors. Commission of a violent crime was based on parole officer report.
RESULTS:
Findings indicated that SUD symptomology was associated with greater externalizing behaviors at high levels of PTSD symptomology. At low levels of PTSD symptomology, SUD symptoms were inversely associated with externalizing behaviors. An interactive relationship was not observed for commission of violent crimes.
CONCLUSIONS:
Findings suggest that the association between SUD symptoms and externalizing behaviors among juvenile offenders may be best explained by the presence of PTSD symptomology.
SCIENTIFIC SIGNIFICANCE:
Addressing PTSD rather than SUD symptoms may be a better target for reducing risk for externalizing behaviors among this population of youth (Am J Addict 2019;28:29-35)
Some Variations on Maxwell's Equations
In the first sections of this article, we discuss two variations on Maxwell's
equations that have been introduced in earlier work--a class of nonlinear
Maxwell theories with well-defined Galilean limits (and correspondingly
generalized Yang-Mills equations), and a linear modification motivated by the
coupling of the electromagnetic potential with a certain nonlinear Schroedinger
equation. In the final section, revisiting an old idea of Lorentz, we write
Maxwell's equations for a theory in which the electrostatic force of repulsion
between like charges differs fundamentally in magnitude from the electrostatic
force of attraction between unlike charges. We elaborate on Lorentz'
description by means of electric and magnetic field strengths, whose governing
equations separate into two fully relativistic Maxwell systems--one describing
ordinary electromagnetism, and the other describing a universally attractive or
repulsive long-range force. If such a force cannot be ruled out {\it a priori}
by known physical principles, its magnitude should be determined or bounded
experimentally. Were it to exist, interesting possibilities go beyond Lorentz'
early conjecture of a relation to (Newtonian) gravity.Comment: 26 pages, submitted to a volume in preparation to honor Gerard Emch
v. 2: discussion revised, factors of 4\pi corrected in some equation
Performance analysis of a parallel, multi-node pipeline for DNA sequencing
Post-sequencing DNA analysis typically consists of read mapping followed by variant calling and is very time-consuming, even on a multi-core machine. Recently, we proposed Halvade, a parallel, multi-node implementation of a DNA sequencing pipeline according to the GATK Best Practices recommendations. The MapReduce programming model is used to distribute the workload among different workers. In this paper, we study the impact of different hardware configurations on the performance of Halvade. Benchmarks indicate that especially the lack of good multithreading capabilities in the existing tools (BWA, SAMtools, Picard, GATK) cause suboptimal scaling behavior. We demonstrate that it is possible to circumvent this bottleneck by using multiprocessing on high-memory machines rather than using multithreading. Using a 15-node cluster with 360 CPU cores in total, this results in a runtime of 1 h 31 min. Compared to a single-threaded runtime of similar to 12 days, this corresponds to an overall parallel efficiency of 53%
Analytical and numerical analyses of the micromechanics of soft fibrous connective tissues
State of the art research and treatment of biological tissues require
accurate and efficient methods for describing their mechanical properties.
Indeed, micromechanics motivated approaches provide a systematic method for
elevating relevant data from the microscopic level to the macroscopic one. In
this work the mechanical responses of hyperelastic tissues with one and two
families of collagen fibers are analyzed by application of a new variational
estimate accounting for their histology and the behaviors of their
constituents. The resulting, close form expressions, are used to determine the
overall response of the wall of a healthy human coronary artery. To demonstrate
the accuracy of the proposed method these predictions are compared with
corresponding 3-D finite element simulations of a periodic unit cell of the
tissue with two families of fibers. Throughout, the analytical predictions for
the highly nonlinear and anisotropic tissue are in agreement with the numerical
simulations
Drawing Planar Graphs with Few Geometric Primitives
We define the \emph{visual complexity} of a plane graph drawing to be the
number of basic geometric objects needed to represent all its edges. In
particular, one object may represent multiple edges (e.g., one needs only one
line segment to draw a path with an arbitrary number of edges). Let denote
the number of vertices of a graph. We show that trees can be drawn with
straight-line segments on a polynomial grid, and with straight-line
segments on a quasi-polynomial grid. Further, we present an algorithm for
drawing planar 3-trees with segments on an
grid. This algorithm can also be used with a small modification to draw maximal
outerplanar graphs with edges on an grid. We also
study the problem of drawing maximal planar graphs with circular arcs and
provide an algorithm to draw such graphs using only arcs. This is
significantly smaller than the lower bound of for line segments for a
nontrivial graph class.Comment: Appeared at Proc. 43rd International Workshop on Graph-Theoretic
Concepts in Computer Science (WG 2017
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