1,108 research outputs found
Effective Monopole Action at Finite Temperature in SU(2) Gluodynamics
Effective monopole action at finite temperature in SU(2) gluodynamics is
studied on anisotropic lattices. Using an inverse Monte-Carlo method and the
blockspin transformation for space directions, we determine 4-dimensional
effective monopole action at finite temperature. We get an almost perfect
action in the continuum limit under the assumption that the action is composed
of two-point interactions alone. It depends on a physical scale and the
temperature . The temperature-dependence appears with respect to the
spacelike monopole couplings in the deconfinement phase, whereas the timelike
monopole couplings do not show any appreciable temperature-dependence. The
dimensional reduction of the 4-dimensional SU(2) gluodynamics ((SU(2)))
at high temperature is the 3-dimensional Georgi-Glashow model ().
The latter is studied at the parameter region obtained from the dimensional red
uction. We compare the effective instanton action of with the
timelike monopole action obtained from (SU(2)). We find that both agree
very well for at large region. The dimensional reduction
works well also for the effective action.Comment: 34 pages, 23 figure
Bursts and Horizontal Evolution of DNA Transposons in the Speciation of Pseudotetraploid Salmonids
Background: Several genome duplications have occurred in the evolutionary history of teleostfish. In returning to a stable diploid state, the polyploid genome reorganized, and large portions arelost, while the fish lines evolved to numerous species. Large scale transposon movement has beenpostulated to play an important role in the genome reorganization process. We analyzed the DNAsequence of several large loci in Salmo salar and other species for the presence of DNA transposonfamilies.Results: We have identified bursts of activity of 14 families of DNA transposons (12 Tc1-like and2 piggyBac-like families, including 11 novel ones) in genome sequences of Salmo salar. Several ofthese families have similar sequences in a number of closely and distantly related fish, lamprey, andfrog species as well as in the parasite Schistosoma japonicum. Analysis of sequence similaritiesbetween copies within the families of these bursts demonstrates several waves of transpositionactivities coinciding with salmonid species divergence. Tc1-like families show a master gene-likecopying process, illustrated by extensive but short burst of copying activity, while the piggyBac-likefamilies show a more random copying pattern. Recent families may include copies with an openreading frame for an active transposase enzyme.Conclusion: We have identified defined bursts of transposon activity that make use of masterslaveand random mechanisms. The bursts occur well after hypothesized polyploidy events andcoincide with speciation events. Parasite-mediated lateral transfer of transposons are implicated
Progress and Trends in Artificial Silk Spinning: A Systematic Review
More than 400 million years of natural selection acting throughout the arthropoda has resulted in highly specialized and energetically efficient processes to produce protein-based fibers with properties that are a source of inspiration for all. As a result, for over 80 years researchers have been inspired by natural silk production in their attempts to spin artificial silks. While significant progress has been made, with fibers now regularly outperforming silkworm silks, surpassing the properties of superior silks, such as spider dragline, is still an area of considerable effort. This review provides an overview of the different approaches for artificial silk fiber spinning and compares all published fiber properties to date which has identified future trends and challenges on the road towards replicating high performance silks
Detection of Nav1.5 conformational change in mammalian cells using the non-canonical amino acid ANAP
Nav1.5 inactivation is necessary for healthy conduction of the cardiac action potential. Genetic mutations of Nav1.5 perturb inactivation and cause potentially fatal arrhythmias associated with long QT syndrome type 3. The exact structural dynamics of the inactivation complex is unknown. To sense inactivation gate conformational change in live mammalian cells, we incorporated the solvatochromic fluorescent non-canonical amino acid ANAP into single sites in the Nav1.5 inactivation gate. ANAP was incorporated in full-length and C-terminally truncated Nav1.5 channels using mammalian cell synthetase-tRNA technology. ANAP-incorporated channels were expressed in mammalian cells and they exhibited pathophysiological function. A spectral imaging potassium-depolarization assay was designed to detect ANAP emission shifts associated with Nav1.5 conformational change. Site-specific intracellular ANAP incorporation affords live-cell imaging and detection of Nav1.5 inactivation gate conformational change in mammalian cells
Synthetic Physiology
Optogenetic tools are DNA-encoded molecules that, when genetically targeted to cells, enable the control of specific physiological processes within those cells through exposure to light. These tools can pinpoint how these specific processes affect the emergent properties of a complex biological system, such as a mammalian organ or even an entire animal. They can also allow control of a biological system for therapeutic or bioengineering purposes. Many of the optical control tools explored to date are single-component reagents containing a photoactive signaling domain. An interesting question is raised by comparing optogenetics to synthetic biology. In the latter, interchangeable and modular DNA-encoded parts are assembled into complex biological circuits, thus enabling sophisticated logic and computation as well as the production of biologics and reagents (1, 2). Is it possible to devise strategies for the temporally precise cell-targeted optical control of complex engineered biological computational or chemical-synthetic pathways? Such a marriage of optogenetics and synthetic biology—which one might call synthetic physiology—would open up the ability to use optogenetics to trigger and regulate engineered synthetic biology systems, which in turn could execute computational and biological programs of great complexity (3). On page 1565 of this issue, Ye et al. (4) explore such a hybrid approach to controlling a biological system, as well as the bioengineering and preclinical capabilities opened up by such an approach
Longitudinal Renal Function in Liver Transplant Recipients With Acute-on-Chronic Liver Failure
Association between longer hospitalization and development of de novo donor specific antibodies in simultaneous liver–kidney transplant recipients
© 2019, © 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. Background:De novo Donor Specific Antibodies (DSA) are considered as a risk factor for the kidney allograft outcomes in recipients after simultaneous liver–kidney transplantation (SLKT). We hypothesized that length of hospital stay (LOS) might be associated with de novo DSA development of due to the increased likelihood of receiving blood transfusions with reduced immunosuppressive regimens. Methods: This study is a single-center, retrospective cohort study consisting of 85 recipients who underwent SLKT from 2009 to 2018 in our hospital. We divided the patients into two groups according to LOS [long hospital stay (L) group (LOS \u3e14 days) and short hospital stay (S) group (LOS ≤14 days)]. Propensity score (PS) has been created using logistic regression to predict LOS greater than median of 14 days. The association between the presence of de novo DSA and LOS was assessed by logistic regression models adjusted for PS. Results: The mean age at transplantation of the entire cohort was 55.5 ± 10.1 years. Sixty percent of the recipients were male and Caucasian. Median LOS in (L) group was three-fold longer than (S) group [L: median 30 days (IQR: 21–52), S: median 8.5 days (IQR: 7–11)]. Eight patients developed de novo DSA after SLKT (9.4%), all of them were in (L) group. Longer LOS was significantly associated with higher risk of development of de novo DSA in unadjusted (OR+ each 5 days: 1.09, 95% CI:1.02–1.16) and PS adjusted (OR+ each 5 days: 1.11, 95% CI:1.02–1.21) analysis. Conclusion: Longer hospitalization is significantly associated with the development of de novo DSA in SLKT
Original observations of Desmozoon lepeophtherii, a microsporidian hyperparasite infecting the salmon louse Lepeophtheirus salmonis, and its subsequent detection by other researchers
A microsporidian hyperparasite, Desmozoon lepeophtherii, of the parasitic copepod Lepeophtheirus salmonis (salmon louse), infecting farmed Atlantic salmon (Salmo salar), was first discovered in the west of Scotland in 2000. Heavily infected salmon lice are easily recognised as they have large opaque inclusions distributed throughout the body. The prevalence of salmon lice with visible signs of microsporidiosis can be up to 10% of the population from certain farm sites. The microsporidian was also isolated from the host Atlantic salmon suggesting it may have a two host life cycle. The authors believe that the infection in immunocompetent salmon may be latent, becoming acute during periods of infection with another pathogen or during sexual maturation. Since its first discovery in Scotland, Desmozoon lepeophtherii has been subsequently reported from Norway, and more recently from the Pacific coast of North America
Blocking of lattice monopoles from the continuum in hot lattice gluodynamics
The Abelian monopoles in lattice gluodynamics are associated with continuum
monopoles blocked to the lattice. This association allows to predict the
lattice monopole action and density of the (squared) monopole charges from a
continuum monopole model. The method is applied to the static monopoles in high
temperature gluodynamics. We show that the numerical data both for the density
and the action of the lattice monopoles can be described in terms of a Coulomb
gas of Abelian monopoles in the continuum.Comment: 23 pages, 9 EPS figures, LaTeX2e uses JHEP3 class file; replaced to
match published versio
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