Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 5 de 5
Filter
Add more filters










Database
Language
Publication year range
1.
Phys Rev Lett ; 124(13): 131301, 2020 Apr 03.
Article in English | MEDLINE | ID: mdl-32302154

ABSTRACT

Using only cosmic microwave background polarization data from the polarbear experiment, we measure B-mode polarization delensing on subdegree scales at more than 5σ significance. We achieve a 14% B-mode power variance reduction, the highest to date for internal delensing, and improve this result to 22% by applying for the first time an iterative maximum a posteriori delensing method. Our analysis demonstrates the capability of internal delensing as a means of improving constraints on inflationary models, paving the way for the optimal analysis of next-generation primordial B-mode experiments.

2.
Phys Rev Lett ; 122(1): 013205, 2019 Jan 11.
Article in English | MEDLINE | ID: mdl-31012657

ABSTRACT

We present a protocol to selectively decouple, recouple, and engineer effective interactions in mesoscopic dipolar spin networks. In particular, we develop a versatile protocol that relies upon magic angle spinning to perform Hamiltonian engineering. By using global control fields in conjunction with a local actuator, such as a diamond nitrogen vacancy center located in the vicinity of a nuclear spin network, both global and local control over the effective couplings can be achieved. We show that the resulting effective Hamiltonian can be well understood within a simple, intuitive geometric picture, and corroborate its validity by performing exact numerical simulations in few-body systems. Applications of our method are in the emerging fields of two-dimensional room temperature quantum simulators in diamond platforms, as well as in molecular magnet systems.

3.
Allergy ; 70(8): 910-20, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25858686

ABSTRACT

BACKGROUND: Asthma and other Th2 inflammatory conditions have been associated with increased susceptibility to viral infections. The mechanisms by which Th2 cytokines can influence immune responses to infections are largely unknown. METHODS: We measured the effects of Th2 cytokines (IL-4 and IL-13) on bronchial epithelial cell innate immune antiviral responses by assessing interferon (IFN-ß and IFN-λ1) induction following rhinovirus (RV)-16 infection. We also investigated the modulatory effects of Th2 cytokines on Toll-like receptor 3 (TLR3), interferon-responsive factor 3 (IRF3) and nuclear factor (NF)-kB, that is key molecules and transcription factors involved in the rhinovirus-induced interferon production and inflammatory cascade. Pharmacological and redox modulation of these pathways was also assessed. RESULTS: Th2 cytokines impaired RV-16-induced interferon production, increased rhinovirus replication and impaired TLR3 expression in bronchial epithelial cells. These results were replicated in vivo: we found increased IL-4 mRNA levels in nasal epithelial cells from nasal brushing of atopic rhinitis patients and a parallel reduction in TLR3 expression and increased RV-16 replication compared to nonatopic subjects. Mechanistically, Th2 cytokines impaired RV-16-induced activation of IRF3, but had no effects on RV-16-induced NF-kB activation in bronchial epithelial cell cultures. N-acetylcysteine and phosphoinositide 3-kinase (PI3K) inhibitor restored the inhibitory effects of Th2 cytokines over RV-16-induced activation of IRF3. CONCLUSIONS: IL-4 and IL-13, through inhibition of TLR3 expression and signalling (IRF3), impair immune response to RV-16 infection. These data suggest that Th2 conditions increase susceptibility to infections and identify pharmacological approaches with potential to restore impaired immune response in these conditions.


Subject(s)
Cytokines/metabolism , Immunity, Innate/immunology , Rhinovirus/immunology , Toll-Like Receptor 3/metabolism , Asthma/immunology , Asthma/metabolism , Bronchi/cytology , Cells, Cultured , Cytokines/immunology , Disease Susceptibility , Enzyme-Linked Immunosorbent Assay , Epithelial Cells/immunology , Epithelial Cells/metabolism , Humans , Interleukin-13/immunology , Interleukin-13/metabolism , Interleukin-4/immunology , Interleukin-4/metabolism , NF-kappa B/immunology , NF-kappa B/metabolism , Real-Time Polymerase Chain Reaction , Respiratory Mucosa/immunology , Respiratory Mucosa/metabolism , Th2 Cells/immunology , Th2 Cells/metabolism , Toll-Like Receptor 3/immunology
4.
Phys Rev Lett ; 113(21): 215303, 2014 Nov 21.
Article in English | MEDLINE | ID: mdl-25479501

ABSTRACT

We show that density-dependent synthetic gauge fields may be engineered by combining periodically modulated interactions and Raman-assisted hopping in spin-dependent optical lattices. These fields lead to a density-dependent shift of the momentum distribution, may induce superfluid-to-Mott insulator transitions, and strongly modify correlations in the superfluid regime. We show that the interplay between the created gauge field and the broken sublattice symmetry results, as well, in an intriguing behavior at vanishing interactions, characterized by the appearance of a fractional Mott insulator.

5.
Phys Rev Lett ; 104(22): 228901; author reply 228902, 2010 Jun 04.
Article in English | MEDLINE | ID: mdl-20867211
SELECTION OF CITATIONS
SEARCH DETAIL
...