704 research outputs found
The Use of Simulation and Gaming for Enhancing Creative Behavior
to see abstract, download full tex
Extremes of multidimensional Gaussian processes
This paper considers extreme values attained by a centered, multidimensional Gaussian process t) = (X_1(t), ..., X_n(t)) minus drift d(t) = (d_1(t), ..., d_n(t)), on an arbitrary set T. Under mild regularity conditions, we establish the asymptotics of the logarithm of the probability that for some t in T, we have that (for all i = 1, ..., n) X_i(t) - d_i(t) > q_i u, for positive thresholds q_i > 0 and u large. Our findings generalize and extend previously known results for the single-dimensional and two-dimensional case. A number of examples illustrate the theory
Two-loop Renormalization for Nonanticommutative N=1/2 Supersymmetric WZ Model
We study systematically, through two loops, the divergence structure of the
supersymmetric WZ model defined on the N=1/2 nonanticommutative superspace. By
introducing a spurion field to represent the supersymmetry breaking term F^3 we
are able to perform our calculations using conventional supergraph techniques.
Divergent terms proportional to F, F^2 and F^3 are produced (the first two are
to be expected on general grounds) but no higher-point divergences are found.
By adding ab initio F and F^2 terms to the original lagrangian we render the
model renormalizable. We determine the renormalization constants and beta
functions through two loops, thus making it possible to study the
renormalization group flow of the nonanticommutation parameter.Comment: 36 pages, 25 figures, Latex fil
A human colonic crypt culture system to study regulation of stem cell-driven tissue renewal and physiological function
The intestinal epithelium is one of the most rapidly renewing tissues in the human body and fulfils vital physiological roles such as barrier function and transport of nutrients and fluid. Investigation of gut epithelial physiology in health and disease has been hampered by the lack of ex vivo models of the native human intestinal epithelium. Recently, remarkable progress has been made in defining intestinal stem cells and in generating intestinal organoid cultures. In parallel, we have developed a 3D culture system of the native human colonic epithelium that recapitulates the topological hierarchy of stem cell-driven tissue renewal and permits the physiological study of native polarized epithelial cells. Here we describe methods to establish 3D cultures of intact human colonic crypts and conduct real-time imaging of intestinal tissue renewal, cellular signalling, and physiological function, in conjunction with manipulation of gene expression by lentiviral or adenoviral transduction. Visualization of mRNA- and protein-expression patterns in cultured human colonic crypts, and cross-validation with crypts derived from fixed mucosal biopsies, is also described. Alongside studies using intestinal organoids, the near-native human colonic crypt culture model will help to bridge the gap that exists between investigation of colon cancer cell lines and/or animal (tissue) studies, and progression to clinical trials. To this end, the near native human colonic crypt model provides a platform to aid the development of novel strategies for the prevention of inflammatory bowel disease and cancer
Scalar field propagation in the phi^4 kappa-Minkowski model
In this article we use the noncommutative (NC) kappa-Minkowski phi^4 model
based on the kappa-deformed star product, ({*}_h). The action is modified by
expanding up to linear order in the kappa-deformation parameter a, producing an
effective model on commutative spacetime. For the computation of the tadpole
diagram contributions to the scalar field propagation/self-energy, we
anticipate that statistics on the kappa-Minkowski is specifically
kappa-deformed. Thus our prescription in fact represents hybrid approach
between standard quantum field theory (QFT) and NCQFT on the kappa-deformed
Minkowski spacetime, resulting in a kappa-effective model. The propagation is
analyzed in the framework of the two-point Green's function for low,
intermediate, and for the Planckian propagation energies, respectively.
Semiclassical/hybrid behavior of the first order quantum correction do show up
due to the kappa-deformed momentum conservation law. For low energies, the
dependence of the tadpole contribution on the deformation parameter a drops out
completely, while for Planckian energies, it tends to a fixed finite value. The
mass term of the scalar field is shifted and these shifts are very different at
different propagation energies. At the Planckian energies we obtain the
direction dependent kappa-modified dispersion relations. Thus our
kappa-effective model for the massive scalar field shows a birefringence
effect.Comment: 23 pages, 2 figures; To be published in JHEP. Minor typos corrected.
Shorter version of the paper arXiv:1107.236
-Deformation of Poincar\'e Superalgebra with Classical Lorentz Subalgebra and its Graded Bicrossproduct Structure
The -deformed Poincar{\'e} superalgebra written in Hopf
superalgebra form is transformed to the basis with classical Lorentz subalgebra
generators. We show that in such a basis the -deformed Poincare
superalgebra can be written as graded bicrossproduct. We show that the
-deformed superalgebra acts covariantly on -deformed
chiral superspace.Comment: 13 pages, late
Clinical Practice Guidelines for Recall and Maintenance of Patients with Tooth-Borne and Implant-Borne Dental Restorations
Purpose
To provide guidelines for patient recall regimen, professional maintenance regimen, and at-home maintenance regimen for patients with tooth-borne and implant-borne removable and fixed restorations.
Materials and Methods
The American College of Prosthodontists (ACP) convened a scientific panel of experts appointed by the ACP, American Dental Association (ADA), Academy of General Dentistry (AGD), and American Dental Hygienists Association (ADHA) who critically evaluated and debated recently published findings from two systematic reviews on this topic. The major outcomes and consequences considered during formulation of the clinical practice guidelines (CPGs) were risk for failure of tooth- and implant-borne restorations. The panel conducted a round table discussion of the proposed guidelines, which were debated in detail. Feedback was used to supplement and refine the proposed guidelines, and consensus was attained.
Results
A set of CPGs was developed for tooth-borne restorations and implant-borne restorations. Each CPG comprised (1) patient recall, (2) professional maintenance, and (3) at-home maintenance. For tooth-borne restorations, the professional maintenance and at-home maintenance CPGs were subdivided for removable and fixed restorations. For implant-borne restorations, the professional maintenance CPGs were subdivided for removable and fixed restorations and further divided into biological maintenance and mechanical maintenance for each type of restoration. The at-home maintenance CPGs were subdivided for removable and fixed restorations.
Conclusions
The clinical practice guidelines presented in this document were initially developed using the two systematic reviews. Additional guidelines were developed using expert opinion and consensus, which included discussion of the best clinical practices, clinical feasibility, and risk-benefit ratio to the patient. To the authorsâ knowledge, these are the first CPGs addressing patient recall regimen, professional maintenance regimen, and at-home maintenance regimen for patients with tooth-borne and implant-borne restorations. This document serves as a baseline with the expectation of future modifications when additional evidence becomes available
A Systematic Review of Recall Regimen and Maintenance Regimen of Patients with Dental Restorations. Part 2: Implant-Borne Restorations
Purpose
To evaluate the current scientific evidence on patient recall and maintenance of implant-supported restorations, to standardize patient care regimens and improve maintenance of oral health. An additional purpose was to examine areas of deficiency in the current scientific literature and provide recommendations for future studies.
Materials and Methods
An electronic search for articles in the English language literature from the past 10 years was performed independently by multiple investigators using a systematic search process. After application of predetermined inclusion and exclusion criteria, the final list of articles was reviewed to meet the objectives of this review.
Results
The initial electronic search resulted in 2816 titles. The systematic application of inclusion and exclusion criteria resulted in 14 articles that satisfied the study objectives. An additional 6 articles were added through a supplemental search process for a total of 20 studies. Of these, 11 were randomized controlled clinical trials, and 9 were observational studies. The majority of the studies (15 out of 20) were conducted in the past 5 years and most studies were conducted in Europe (15), followed by Asia (2), South America (1), the United States (1), and the Middle East (1). Results from the qualitative data on a combined 1088 patients indicated that outcome improvements in recall and maintenance regimen were related to (1) patient/treatment characteristic (type of prosthesis, type of prosthetic components, and type of restorative materials); (2) specific oral topical agents or oral hygiene aids (electric toothbrush, interdental brush, chlorhexidine, triclosan, water flossers) and (3) professional intervention (oral hygiene maintenance, and maintenance of the prosthesis).
Conclusions
There is minimal evidence related to recall regimens in patients with implant-borne removable and fixed restorations; however, a considerable body of evidence indicates that patients with implant-borne removable and fixed restorations require lifelong professional recall regimens to provide biological and mechanical maintenance, customized for each patient. Current evidence also demonstrates that the use of specific oral topical agents and oral hygiene aids can improve professional and at-home maintenance of implant-borne restorations. There is evidence to demonstrate differences in mechanical and biological maintenance needs due to differences in prosthetic materials and designs. Deficiencies in existing evidence compel the forethought of creating clinical practice guidelines for recall and maintenance of patients with implant-borne dental restorations
Improving your target-template alignment with MODalign
Summary: MODalign is an interactive web-based tool aimed at helping protein structure modelers to inspect and manually modify the alignment between the sequences of a target protein and of its template(s). It interactively computes, displays and, upon modification of the target-template alignment, updates the multiple sequence alignments of the two protein families, their conservation score, secondary structure and solvent accessibility values, and local quality scores of the implied three-dimensional model(s). Although it has been designed to simplify the target-template alignment step in modeling, it is suitable for all cases where a sequence alignment needs to be inspected in the context of other biological information
- âŠ