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Genes and Pathways Regulating Decline in Lung Function and Airway Remodeling in Asthma.
Asthma is a common disorder of the airways characterized by airway inflammation and by decline in lung function and airway remodeling in a subset of asthmatics. Airway remodeling is characterized by structural changes which include airway smooth muscle hypertrophy/hyperplasia, subepithelial fibrosis due to thickening of the reticular basement membrane, mucus metaplasia of the epithelium, and angiogenesis. Epidemiologic studies suggest that both genetic and environmental factors may contribute to decline in lung function and airway remodeling in a subset of asthmatics. Environmental factors include respiratory viral infection-triggered asthma exacerbations, and tobacco smoke. There is also evidence that several asthma candidate genes may contribute to decline in lung function, including ADAM33, PLAUR, VEGF, IL13, CHI3L1, TSLP, GSDMB, TGFB1, POSTN, ESR1 and ARG2. In addition, mediators or cytokines, including cysteinyl leukotrienes, matrix metallopeptidase-9, interleukin-33 and eosinophil expression of transforming growth factor-β, may contribute to airway remodeling in asthma. Although increased airway smooth muscle is associated with reduced lung function (i.e. forced expiratory volume in 1 second) in asthma, there have been few long-term studies to determine how individual pathologic features of airway remodeling contribute to decline in lung function in asthma. Clinical studies with inhibitors of individual gene products, cytokines or mediators are needed in asthmatic patients to identify their individual role in decline in lung function and/or airway remodeling
On probabilistic analog automata
We consider probabilistic automata on a general state space and study their
computational power. The model is based on the concept of language recognition
by probabilistic automata due to Rabin and models of analog computation in a
noisy environment suggested by Maass and Orponen, and Maass and Sontag. Our
main result is a generalization of Rabin's reduction theorem that implies that
under very mild conditions, the computational power of the automaton is limited
to regular languages
General Relation between Entanglement and Fluctuations in One Dimension
In one dimension very general results from conformal field theory and exact
calculations for certain quantum spin systems have established universal
scaling properties of the entanglement entropy between two parts of a critical
system. Using both analytical and numerical methods, we show that if particle
number or spin is conserved, fluctuations in a subsystem obey identical scaling
as a function of subsystem size, suggesting that fluctuations are a useful
quantity for determining the scaling of entanglement, especially in higher
dimensions. We investigate the effects of boundaries and subleading corrections
for critical spin and bosonic chains.Comment: 4 pages, 2 figures. Minor changes, references added
Chaotic quantum ratchets and filters with cold atoms in optical lattices: properties of Floquet states
Recently, cesium atoms in optical lattices subjected to cycles of
unequally-spaced pulses have been found to show interesting behavior: they
represent the first experimental demonstration of a Hamiltonian ratchet
mechanism, and they show strong variability of the Dynamical Localization
lengths as a function of initial momentum. The behavior differs qualitatively
from corresponding atomic systems pulsed with equal periods, which are a
textbook implementation of a well-studied quantum chaos paradigm, the quantum
delta-kicked particle (delta-QKP). We investigate here the properties of the
corresponding eigenstates (Floquet states) in the parameter regime of the new
experiments and compare them with those of the eigenstates of the delta-QKP at
similar kicking strengths. We show that, with the properties of the Floquet
states, we can shed light on the form of the observed ratchet current as well
as variations in the Dynamical Localization length.Comment: 9 pages, 9 figure
Design of small CRPA arrays with circular microstrip loops for electromagnetically coupled feed
This paper proposes a design of small controlled reception pattern antenna (CRPA) arrays using circular microstrip loops with frequencyinsensitive characteristics. The proposed array consists of seven identical upper and lower circular loops that are electromagnetically coupled, which results in a frequency-insensitive behavior. To demonstrate the feasibility of the proposed feeding mechanism, the proposed array is fabricated, and its antenna characteristics are measured in a full-anechoic chamber. The operating principle of the proposed feeding mechanism is then interpreted using an equivalent circuit model, and the effectiveness of the circular loop shape is demonstrated by calculating near electromagnetic fields in proximity to the radiator. The results confirm that the proposed feeding mechanism is suitable to have frequency- insensitive behavior and induces strong electric and magnetic field strengths for higher radiation gain in extremely small antenna arrays
Time-reversal symmetry breaking in circuit-QED based photon lattices
Breaking time-reversal symmetry is a prerequisite for accessing certain
interesting many-body states such as fractional quantum Hall states. For
polaritons, charge neutrality prevents magnetic fields from providing a direct
symmetry breaking mechanism and similar to the situation in ultracold atomic
gases, an effective magnetic field has to be synthesized. We show that in the
circuit QED architecture, this can be achieved by inserting simple
superconducting circuits into the resonator junctions. In the presence of such
coupling elements, constant parallel magnetic and electric fields suffice to
break time-reversal symmetry. We support these theoretical predictions with
numerical simulations for realistic sample parameters, specify general
conditions under which time-reversal is broken, and discuss the application to
chiral Fock state transfer, an on-chip circulator, and tunable band structure
for the Kagome lattice.Comment: minor revisions, version published in PRA; 19 pages, 13 figures, 2
table
Entanglement from Charge Statistics: Exact Relations for Many-Body Systems
We present exact formulas for the entanglement and R\'{e}nyi entropies
generated at a quantum point contact (QPC) in terms of the statistics of charge
fluctuations, which we illustrate with examples from both equilibrium and
non-equilibrium transport. The formulas are also applicable to groundstate
entanglement in systems described by non-interacting fermions in any dimension,
which in one dimension includes the critical spin-1/2 XX and Ising models where
conformal field theory predictions for the entanglement and R\'{e}nyi entropies
are reproduced from the full counting statistics. These results may play a
crucial role in the experimental detection of many-body entanglement in
mesoscopic structures and cold atoms in optical lattices
Scaling of entanglement entropy across Lifshitz transitions
We investigate the scaling of the bipartite entanglement entropy across
Lifshitz quantum phase transitions, where the topology of the Fermi surface
changes without any changes in symmetry. We present both numerical and
analytical results which show that Lifshitz transitions are characterized by a
well-defined set of critical exponents for the entanglement entropy near the
phase transition. In one dimension, we show that the entanglement entropy
exhibits a length scale that diverges as the system approaches a Lifshitz
critical point. In two dimensions, the leading and sub-leading coefficients of
the scaling of entanglement entropy show distinct power-law singularities at
critical points. The effect of weak interactions is investigated using the
density matrix renormalization group algorithm.Comment: 11 pages, 11 figures; v2) references adde
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