Substantial nuclear ordering in solid He3

Journal ArticleEvidence for a substantial nuclear ordering in solid bcc He3 at melting pressure has been inferred from solid entropies s s deduced from measurements of the slope of the melting curve for a liquid-solid mixture cooled by adiabatic compression. At 3.4 mK we find experimentally that sS/R = 0.83 ln2. It is likely that much lower temperatures and solid entropies are obtained during parts of the experiments. The possibility for bulk nuclear polarization is also discussed

Distributed Approximation of Minimum Routing Cost Trees

We study the NP-hard problem of approximating a Minimum Routing Cost Spanning Tree in the message passing model with limited bandwidth (CONGEST model). In this problem one tries to find a spanning tree of a graph $G$ over $n$ nodes that minimizes the sum of distances between all pairs of nodes. In the considered model every node can transmit a different (but short) message to each of its neighbors in each synchronous round. We provide a randomized $(2+\epsilon)$-approximation with runtime $O(D+\frac{\log n}{\epsilon})$ for unweighted graphs. Here, $D$ is the diameter of $G$. This improves over both, the (expected) approximation factor $O(\log n)$ and the runtime $O(D\log^2 n)$ of the best previously known algorithm. Due to stating our results in a very general way, we also derive an (optimal) runtime of $O(D)$ when considering $O(\log n)$-approximations as done by the best previously known algorithm. In addition we derive a deterministic $2$-approximation

Mesons as qbar-q Bound States from Euclidean 2-Point Correlators in the Bethe-Salpeter Approach

We investigate the 2-point correlation function for the vector current. The gluons provide dressings for both the quark self energy as well as the vector vertex function, which are described consistently by the rainbow Dyson-Schwinger equation and the inhomogeneous ladder Bethe-Salpeter equation. The form of the gluon propagator at low momenta is modeled by a 2-parameter ansatz fitting the weak pion decay constant. The quarks are confined in the sense that the quark propagator does not have a pole at timelike momenta. We determine the ground state mass in the vector channel from the Euclidean time Fourier transform of the correlator, which has an exponential falloff at large times. The ground state mass lies around 590 MeV and is almost independent of the model form for the gluon propagator. This method allows us to stay in Euclidean space and to avoid analytic continuation of the quark or gluon propagators into the timelike region.Comment: 21 pages (REVTEX), 8 Postscript figure

Strategies for Oligoribonucleotide Synthesis According to the Phosphoramidite Method

Advances in oligoribonucleotide synthesis have lagged behind those in oligodeoxyribonucleotide synthesis because of the difficulty in identifying orthogonal protecting groups for the 2′‐ and 5′‐hydroxyls. Adaptation of the phosphoramidite method for DNA synthesis to RNA synthesis has greatly improved our understanding of RNA. It allows site‐specific introduction of modified nucleosides to any position in an RNA molecule, as well as introduction of variations at multiple sites in the molecule. This overview discusses issues that are relevant to RNA synthesis by the phosphoramidite approach, including supports used, activation of the ribonucleoside phosphoramidites, and protection of the nucleobase, phosphate, and 2′‐ and 5′‐hydroxyls.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143793/1/cpnc0305.pd

Feasibility study and design concept for an orbiting ice-penetrating radar sounder to characterize in three-dimensions the Europan ice mantle down to (and including) any ice/ocean interface

This report presents a radar sounding model based on the range of current working hypotheses for the nature of Europa's icy shell.Institute for Geophysic

A Case Study on the Impact of Web-based Technology in a Simulation Analysis Course

A case study is presented on the use of web-based technol ogy to transition from a lecture-based delivery system to an online/multimedia technology delivery system at the University of Oklahoma's School of Industrial Engineer ing. Coupling web and multimedia technology with a pyramid approach to a simulation course sequence, the goal is to provide both undergraduate and graduate stu dents with strong simulation skills in both modeling and analysis. Web-based technology is used to provide course access to non-traditional students, to re-enforce prerequi site knowledge, and to support learning statistical con cepts. The approach has been successful at (i) generating two types of graduates, the simulation modeler and the simulation analyst/consultant, (ii) increasing the reten tion of non-traditional students (industrial engineering students with full-time jobs and other engineering majors without strong statistical backgrounds), and (iii) gradu ating two non-traditional students in the School's master's degree program as based on their research in simulation analysis. However, online technologies are not without their disadvantages. While the burden has been eased on student learning and their out-of-class activities, the faculty is now tasked with an increased load of sup porting online courses and utilizing web-based technolo gies both within and outside the classroom.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

Subject-specific, multiscale simulation of electrophysiology: a software pipeline for image-based models and application examples

Many simulation studies in biomedicine are based on a similar sequence of processing steps, starting from images and running through geometric model generation, assignment of tissue properties, numerical simulation and visualization of the results—a process known as image-based geometric modelling and simulation. We present an overview of software systems for implementing such a sequence both within highly integrated problem-solving environments and in the form of loosely integrated pipelines. Loose integration in this case indicates that individual programs function largely independently but communicate through files of a common format and support simple scripting, so as to automate multiple executions wherever possible. We then describe three specific applications of such pipelines to translational biomedical research in electrophysiology

Companion animals are spillover hosts of the Multidrug-resistant human extraintestinal escherichia coli pandemic Clones ST131 and ST1193

Escherichia coli sequence types 131 (ST131) and 1193 are multidrug-resistant extraintestinal pathogens that have recently spread epidemically among humans and are occasionally isolated from companion animals. This study characterized a nationwide collection of fluoroquinolone-resistant (FQR) E. coli isolates from extraintestinal infections in Australian cats and dogs. For this, 59 cat and dog FQR clinical E. coli isolates (representing 6.9% of an 855-isolate collection) underwent PCR-based phylotyping and whole-genome sequencing (WGS). Isolates from commensal-associated phylogenetic groups A (14/59, 24%) and B1 (18/59, 31%) were dominant, with ST224 (10/59, 17%), and ST744 (8/59, 14%) predominating. Less prevalent were phylogenetic groups D (12/59, 20%), with ST38 (8/59, 14%) predominating, and virulence-associated phylogenetic group B2 (7/59, 12%), with ST131 predominating (6/7, 86%) and no ST1193 isolates identified. In a WGS-based comparison of 20 cat and dog-source ST131 isolates with 188 reference human and animal ST131 isolates, the cat and dog-source isolates were phylogenetically diverse. Although cat and dog-source ST131 isolates exhibited some minor sub-clustering, most were closely related to human-source ST131 strains. Furthermore, the prevalence of ST131 as a cause of FQR infections in Australian companion animals was relatively constant between this study and the 5-year-earlier study of Platell et al. (2010) (9/125 isolates, 7.2%). Thus, although the high degree of clonal commonality among FQR clinical isolates from humans vs. companion animals suggests the possibility of bi-directional between-species transmission, the much higher reported prevalence of ST131 and ST1193 among FQR clinical isolates from humans as compared to companion animals suggests that companion animals are spillover hosts rather than being a primary reservoir for these lineages

Prusa 3-D Printer Position Error: Conceptualization and Testbed Design

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