45 research outputs found
Three-dimensional super Yang-Mills with unquenched flavor
We construct analytically the gravity duals of three-dimensional, super
Yang-Mills-type theories with supersymmetry coupled to
quark flavors. The backreaction of the quarks on the color degrees of freedom
is included, and corresponds on the gravity side to the backreaction of
D6-branes on the background of D2-branes. The D6-branes are smeared over
the compact part of the geometry, which must be a six-dimensional nearly
K\"ahler manifold in order to preserve supersymmetry. For massless quarks, the
solutions flow in the IR to an fixed point dual to a
Chern-Simons-matter theory. For light quarks the theories exhibit
quasi-conformal dynamics (walking) at energy scales , with the 't Hooft coupling.Comment: 21 pages, 1 figure. v2 Minor editing, refs. added. Tallies with
published versio
(Super)Yang-Mills at Finite Heavy-Quark Density
We study the gravitational duals of -dimensional Yang-Mills theories with
in the presence of an density of heavy quarks, with
the number of colors. For concreteness we focus on maximally supersymmetric
Yang-Mills, but our results apply to a larger class of theories with or without
supersymmetry. The gravitational solutions describe renormalization group flows
towards infrared scaling geometries characterized by fixed dynamical and
hyperscaling-violating exponents. The special case yields an geometry upon uplifting to M-theory. We discuss
the multitude of physical scales that separate different dynamical regimes
along the flows, as well as the validity of the supergravity description. We
also present exact black brane solutions that encode the low-temperature
thermodynamics.Comment: 40 pages, 8 figures, 2 table
Multiple Mass Hierarchies from Complex Fixed Point Collisions
A pair of complex-conjugate fixed points that lie close to the real axis
generates a large mass hierarchy in the real renormalization group flow that
passes in between them. We show that pairs of complex fixed points that are
close to the real axis and to one another generate multiple hierarchies, some
of which can be parametrically enhanced. We illustrate this effect at weak
coupling with field-theory examples, and at strong coupling using holography.
We also construct complex flows between complex fixed points, including flows
that violate the -theorem.Comment: 24 pages + appendices, 12 figure
Anti-trbc1 antibody-based flow cytometric detection of t-cell clonality: Standardization of sample preparation and diagnostic implementation
© 2021 by the authors.A single antibody (anti-TRBC1; JOVI-1 antibody clone) against one of the two mutually exclusive T-cell receptor ÎČ-chain constant domains was identified as a potentially useful flow-cytometry (FCM) marker to assess TαÎČ-cell clonality. We optimized the TRBC1-FCM approach for detecting clonal TαÎČ-cells and validated the method in 211 normal, reactive and pathological samples. TRBC1 labeling significantly improved in the presence of CD3. Purified TRBC1+ and TRBC1â monoclonal and polyclonal TαÎČ-cells rearranged TRBJ1 in 44/47 (94%) and TRBJ1+TRBJ2 in 48 of 48 (100%) populations, respectively, which confirmed the high specificity of this assay. Additionally, TRBC1+/TRBC1â ratios within different TαÎČ-cell subsets are provided as reference for polyclonal cells, among which a bimodal pattern of TRBC1-expression profile was found for all TCRVÎČ families, whereas highly-variable TRBC1+/TRBC1â ratios were observed in more mature vs. naĂŻve TαÎČ-cell subsets (vs. total T-cells). In 112/117 (96%) samples containing clonal TαÎČ-cells in which the approach was validated, monotypic expression of TRBC1 was confirmed. Dilutional experiments showed a level of detection for detecting clonal TαÎČ-cells of â€10â4 in seven out of eight pathological samples. These results support implementation of the optimized TRBC1-FCM approach as a fast, specific and accurate method for assessing T-cell clonality in diagnostic-FCM panels, and for minimal (residual) disease detection in mature TαÎČ+ leukemia/lymphoma patients.This work was supported by the CB16/12/00400 (CIBERONC) and PI20-01346 grants, from the Instituto de Salud Carlos III, Ministerio de Ciencia e InnovaciĂłn (Madrid, Spain) and FONDOS FEDER, and by the EuroFlow Foundation (Leiden, The Netherlands). N. Muñoz-GarcĂa is supported by a pre-doctoral grant (Ref. IBPredoc17/00012) from IBSAL (Salamanca, Spain). M. Lima, N. Villamor, A.W. Langerak, J.J.M. van Dongen, A. Orfao, and J. Almeida are members of the EuroFlow Consortiu
Quantifying and addressing the prevalence and bias of study designs in the environmental and social sciences
Abstract: Building trust in science and evidence-based decision-making depends heavily on the credibility of studies and their findings. Researchers employ many different study designs that vary in their risk of bias to evaluate the true effect of interventions or impacts. Here, we empirically quantify, on a large scale, the prevalence of different study designs and the magnitude of bias in their estimates. Randomised designs and controlled observational designs with pre-intervention sampling were used by just 23% of intervention studies in biodiversity conservation, and 36% of intervention studies in social science. We demonstrate, through pairwise within-study comparisons across 49 environmental datasets, that these types of designs usually give less biased estimates than simpler observational designs. We propose a model-based approach to combine study estimates that may suffer from different levels of study design bias, discuss the implications for evidence synthesis, and how to facilitate the use of more credible study designs