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MINORITIZED GROUPS AND SOCIAL INTEGRATION AND RECOVERY CAPITAL DEVELOPMENT IN MUTUAL AID FELLOWSHIPS
The aim of this study was to examine the relationship between the level of engagement in recovery oriented mutual aid self-help groups one has, and the development of Recovery Capital (RC), an important variable in the recovery process from substance use disorders (SUDs). This study further assessed the correlation between self-help engagement and RC development for persons from minoritized groups. Results of this study can help social workers understand the efficacy of referrals to free, community-based mutual aid recovery programs for individuals from different demographic backgrounds, particularly those from minoritized groups, who often face barriers to treatment. A survey of a non- probability sample of 215 individuals who self-identify as in recovery was utilized to collect information on demographic characteristics, level of engagement in self-help recovery groups, and level of recovery capital. Quantitative analyses were conducted to compare correlation coefficients between self-help involvement and recovery capital development amongst minoritized groups. The results of this study support the correlation between self-help engagement with RC, as well as the findings indicate that there is no significant difference in results with varying ethnic backgrounds. This study provides evidence that self-help groups such as 12-step meetings are a valuable resource regardless of being from an ethnically minoritized group
Local Integrals of Motion for Topologically Ordered Many-Body Localized Systems
Many-body localized (MBL) systems are often described using their local
integrals of motion, which, for spin systems, are commonly assumed to be a
local unitary transform of the set of on-site spin-z operators. We show that
this assumption cannot hold for topologically ordered MBL systems. Using a
suitable definition to capture such systems in any spatial dimension, we
demonstrate a number of features, including that MBL topological order, if
present: (i) is the same for all eigenstates; (ii) is robust in character
against any perturbation preserving MBL; (iii) implies that on topologically
nontrivial manifolds a complete set of integrals of motion must include
nonlocal ones in the form of local-unitary-dressed noncontractible Wilson
loops. Our approach is well suited for tensor-network methods, and is expected
to allow these to resolve highly-excited finite-size-split topological
eigenspaces despite their overlap in energy. We illustrate our approach on the
disordered Kitaev chain, toric code, and X-cube model.Comment: 5 pages, 1 figur
Local integrals of motion detection of localization-protected topological order
Many-body-localized (MBL) phases can be topologically distinct, but
distinguishing these phases using order parameters can be challenging. Here we
show how topologically distinct local integrals of motion, variationally
parametrized by quantum circuits, can be used to numerically demonstrate the
topological inequivalence of MBL phases. We illustrate our approach on a
fermionic chain where both topologically distinct MBL phases and benchmark
comparisons to order parameters are possible. We also use our approach,
augmented by the DMRG-X algorithm, to extract high-energy topological doublets.
We describe applying our methods to higher dimensions to identify MBL
topological order and topological multiplets hidden by the dense many-body
spectrum.Comment: 8 pages, 7 figures; v2: accepted manuscript; v3: typo fixe
Stromal mesenteric lymph node cells are essential for the generation of gut-homing T cells in vivo
T cells primed in the gut-draining mesenteric lymph nodes (mLN) are imprinted to express α4β7-integrin and chemokine receptor CCR9, thereby enabling lymphocytes to migrate to the small intestine. In vitro activation by intestinal dendritic cells (DC) or addition of retinoic acid (RA) is sufficient to instruct expression of these gut-homing molecules. We report that in vivo stroma cells, but not DC, allow the mLN to induce the generation of gut tropism. Peripheral LN (pLN) transplanted into the gut mesenteries fail to support the generation of gut-homing T cells, even though gut-derived DC enter the transplants and prime T cells. DC that fail to induce α4β7-integrin and CCR9 in vitro readily induce these factors in vivo upon injection into mLN afferent lymphatics. Moreover, uniquely mesenteric but not pLN stroma cells express high levels of RA-producing enzymes and support induction of CCR9 on activated T cells in vitro. These results demonstrate a hitherto unrecognized contribution of stromal cell delivered signals, including RA, on the imprinting of tissue tropism in vivo
Cardiosphere-derived cells demonstrate metabolic flexibility that Is influenced by adhesion status
Adult stem cells demonstrate metabolic flexibility that is regulated by cell adhesion status. The authors demonstrate that adherent cells primarily utilize glycolysis, whereas suspended cells rely on oxidative phosphorylation for their ATP needs. Akt phosphorylation transduces adhesion-mediated regulation of energy metabolism, by regulating translocation of glucose transporters (GLUT1) to the cell membrane and thus, cellular glucose uptake and glycolysis. Cell dissociation, a pre-requisite for cell transplantation, leads to energetic stress, which is mediated by Akt dephosphorylation, downregulation of glucose uptake, and glycolysis. They designed hydrogels that promote rapid cell adhesion of encapsulated cells, Akt phosphorylation, restore glycolysis, and cellular ATP levels
Automated quantum error mitigation based on probabilistic error reduction
Current quantum computers suffer from a level of noise that prohibits
extracting useful results directly from longer computations. The figure of
merit in many near-term quantum algorithms is an expectation value measured at
the end of the computation, which experiences a bias in the presence of
hardware noise. A systematic way to remove such bias is probabilistic error
cancellation (PEC). PEC requires a full characterization of the noise and
introduces a sampling overhead that increases exponentially with circuit depth,
prohibiting high-depth circuits at realistic noise levels. Probabilistic error
reduction (PER) is a related quantum error mitigation method that
systematically reduces the sampling overhead at the cost of reintroducing bias.
In combination with zero-noise extrapolation, PER can yield expectation values
with an accuracy comparable to PEC.Noise reduction through PER is broadly
applicable to near-term algorithms, and the automated implementation of PER is
thus desirable for facilitating its widespread use. To this end, we present an
automated quantum error mitigation software framework that includes noise
tomography and application of PER to user-specified circuits. We provide a
multi-platform Python package that implements a recently developed Pauli noise
tomography (PNT) technique for learning a sparse Pauli noise model and exploits
a Pauli noise scaling method to carry out PER.We also provide software tools
that leverage a previously developed toolchain, employing PyGSTi for gate set
tomography and providing a functionality to use the software Mitiq for PER and
zero-noise extrapolation to obtain error-mitigated expectation values on a
user-defined circuit.Comment: 11 pages, 9 figure
Acute Downregulation but Not Genetic Ablation of Murine MCU Impairs Suppressive Capacity of Regulatory CD4 T Cells
By virtue of mitochondrial control of energy production, reactive oxygen species (ROS)
generation, and maintenance of Ca2+ homeostasis, mitochondria play an essential role in modulating
T cell function. The mitochondrial Ca2+ uniporter (MCU) is the pore-forming unit in the main protein
complex mediating mitochondrial Ca2+ uptake. Recently, MCU has been shown to modulate Ca2+
signals at subcellular organellar interfaces, thus fine-tuning NFAT translocation and T cell activation.
The mechanisms underlying this modulation and whether MCU has additional T cell subpopulationspecific effects remain elusive. However, mice with germline or tissue-specific ablation of Mcu did
not show impaired T cell responses in vitro or in vivo, indicating that ‘chronic’ loss of MCU can
be functionally compensated in lymphocytes. The current work aimed to specifically investigate
whether and how MCU influences the suppressive potential of regulatory CD4 T cells (Treg). We show
that, in contrast to genetic ablation, acute siRNA-mediated downregulation of Mcu in murine Tregs
results in a significant reduction both in mitochondrial Ca2+ uptake and in the suppressive capacity
of Tregs, while the ratios of Treg subpopulations and the expression of hallmark transcription factors
were not affected. These findings suggest that permanent genetic inactivation of MCU may result in
compensatory adaptive mechanisms, masking the effects on the suppressive capacity of Tregs
Atomic-scale imaging of emergent order at a magnetic-field-induced Lifshitz transition
Funding: UK Engineering and Physical Sciences Research Council, Funder ID: (FUNDREF) 10.13039/501100000266, Grant: EP/L015110/1. UK Engineering and Physical Sciences Research Council, Funder ID:(FUNDREF) 10.13039/501100000266, Grant: EP/R031924/1. Engineering and Physical Sciences Research Council, Funder ID:(FUNDREF) 10.13039/501100000266, Grant: EP/R023751/1. Engineering and Physical Sciences Research Council, Funder ID:(FUNDREF) 10.13039/501100000266, Grant: EP/L017008/1.The phenomenology and radical changes seen in material properties traversing a quantum phase transition have captivated condensed matter research over the past decades. Strong electronic correlations lead to exotic electronic ground states, including magnetic order, nematicity, and unconventional superconductivity. Providing a microscopic model for these requires detailed knowledge of the electronic structure in the vicinity of the Fermi energy, promising a complete understanding of the physics of the quantum critical point. Here, we demonstrate such a measurement at the surface of Sr3Ru2O7. Our results show that, even in zero field, the electronic structure is strongly C2 symmetric and that a magnetic field drives a Lifshitz transition and induces a charge-stripe order. We track the changes of the electronic structure as a function of field via quasiparticle interference imaging at ultralow temperatures. Our results provide a complete microscopic picture of the field-induced changes of the electronic structure across the Lifshitz transition.Publisher PDFPeer reviewe
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