611 research outputs found
Balanced Tripartite Entanglement, the Alternating Group A4 and the Lie Algebra
We discuss three important classes of three-qubit entangled states and their
encoding into quantum gates, finite groups and Lie algebras. States of the GHZ
and W-type correspond to pure tripartite and bipartite entanglement,
respectively. We introduce another generic class B of three-qubit states, that
have balanced entanglement over two and three parties. We show how to realize
the largest cristallographic group in terms of three-qubit gates (with
real entries) encoding states of type GHZ or W [M. Planat, {\it Clifford group
dipoles and the enactment of Weyl/Coxeter group by entangling gates},
Preprint 0904.3691 (quant-ph)]. Then, we describe a peculiar "condensation" of
into the four-letter alternating group , obtained from a chain of
maximal subgroups. Group is realized from two B-type generators and found
to correspond to the Lie algebra . Possible
applications of our findings to particle physics and the structure of genetic
code are also mentioned.Comment: 14 page
Unexpected Learning: Development of the CoP and Its Members #generational-shift
Our research explores how multigenerational CoPs may provide graduate students, particularly doctoral students, the space to explore and develop their professional identities and find their scholarly voices
Uniqueness of radial solutions for the fractional Laplacian
We prove general uniqueness results for radial solutions of linear and
nonlinear equations involving the fractional Laplacian with for any space dimensions . By extending a monotonicity
formula found by Cabre and Sire \cite{CaSi-10}, we show that the linear
equation in has at most one radial and
bounded solution vanishing at infinity, provided that the potential is a
radial and non-decreasing. In particular, this result implies that all radial
eigenvalues of the corresponding fractional Schr\"odinger operator
are simple. Furthermore, by combining these findings on
linear equations with topological bounds for a related problem on the upper
half-space , we show uniqueness and nondegeneracy of ground
state solutions for the nonlinear equation in for arbitrary space dimensions and all
admissible exponents . This generalizes the nondegeneracy and
uniqueness result for dimension N=1 recently obtained by the first two authors
in \cite{FrLe-10} and, in particular, the uniqueness result for solitary waves
of the Benjamin--Ono equation found by Amick and Toland \cite{AmTo-91}.Comment: 38 pages; revised version; various typos corrected; proof of Lemma
8.1 corrected; discussion of case \kappa_* =1 in the proof of Theorem 2
corrected with new Lemma A.2; accepted for publication in Comm. Pure. Appl.
Mat
The effect of aging and cardiorespiratory fitness on the lung diffusing capacity response to exercise in healthy humans
Aging is associated with deterioration in the structure and function of the pulmonary circulation. We characterized the lung diffusing capacity for carbon monoxide (DLCO), alveolar-capillary membrane conductance (Dm(CO)), and pulmonary-capillary blood volume (V(C)) response to discontinuous incremental exercise at 25, 50, 75, and 90% of peak work (Wpeak) in four groups: 1) Young [27 ± 3 y, maximal oxygen consumption (V̇O₂max) 110 ± 18% age-predicted]; 2) Young Highly-Fit (27 ± 3 y, V̇O₂max 147 ± 8% age-predicted); 3) Old (69 ± 5 y, V̇O₂max 116 ± 13% age-predicted); and 4) Old Highly-Fit (65 ± 5 y, V̇O₂max 162 ± 18% age-predicted). At rest and at 90% Wpeak, DLCO, Dm(CO), and VC were decreased with age. At 90% Wpeak, DLCO, Dm(CO) and VC were greater in Old Highly-Fit vs. Old adults. The slope of the DLCO-cardiac output (Q̇) relationship from rest to end-exercise at 90% Wpeak was not different between Young, Young Highly-Fit, Old and Old Highly-Fit (1.35 vs. 1.44 vs. 1.10 vs. 1.35 mlCO·mmHg⁻¹·Lblood⁻¹, P = 0.388), with no evidence of a plateau in this relationship during exercise; this was also true for Dm(CO)-Q̇ and V(C)-Q̇. V̇O2max was positively correlated with: 1) DLCO, Dm(CO), and V(C) at rest; 2) the rest to end-exercise change in DLCO, Dm(CO), and V(C). In conclusion, these data suggest that despite the age-associated deterioration in the structure and function of the pulmonary circulation, expansion of the pulmonary capillary network does not become limited during exercise in healthy individuals regardless of age or cardiorespiratory fitness level
Bounds of concurrence and their relation with fidelity and frontier states
The bounds of concurrence in [F. Mintert and A. Buchleitner, Phys. Rev. Lett.
98 (2007) 140505] and [C. Zhang \textit{et. al.}, Phys. Rev. A 78 (2008)
042308] are proved by using two properties of the fidelity. In two-qubit
systems, for a given value of concurrence, the states achieving the maximal
upper bound, the minimal lower bound or the maximal difference upper-lower
bound are determined analytically
Heparanase deglycanation of syndecan-1 is required for binding of the epithelial-restricted prosecretory mitogen lacritin
Cell surface heparan sulfate (HS) proteoglycans are carbohydrate-rich regulators of cell migratory, mitogenic, secretory, and inflammatory activity that bind and present soluble heparin-binding growth factors (e.g., fibroblast growth factor, Wnt, Hh, transforming growth factor β, amphiregulin, and hepatocyte growth factor) to their respective signaling receptors. We demonstrate that the deglycanated core protein of syndecan-1 (SDC1) and not HS chains nor SDC2 or -4, appears to target the epithelial selective prosecretory mitogen lacritin. An important and novel step in this mechanism is that binding necessitates prior partial or complete removal of HS chains by endogenous heparanase. This limits lacritin activity to sites where heparanase appears to predominate, such as sites of exocrine cell migration, secretion, renewal, and inflammation. Binding is mutually specified by lacritin's C-terminal mitogenic domain and SDC1's N terminus. Heparanase modification of the latter transforms a widely expressed HS proteoglycan into a highly selective surface-binding protein. This novel example of cell specification through extracellular modification of an HS proteoglycan has broad implications in development, homeostasis, and disease
Heralded generation of entangled photon pairs
Entangled photons are a crucial resource for quantum communication and linear
optical quantum computation. Unfortunately, the applicability of many
photon-based schemes is limited due to the stochastic character of the photon
sources. Therefore, a worldwide effort has focused in overcoming the limitation
of probabilistic emission by generating two-photon entangled states conditioned
on the detection of auxiliary photons. Here we present the first heralded
generation of photon states that are maximally entangled in polarization with
linear optics and standard photon detection from spontaneous parametric
down-conversion. We utilize the down-conversion state corresponding to the
generation of three photon pairs, where the coincident detection of four
auxiliary photons unambiguously heralds the successful preparation of the
entangled state. This controlled generation of entangled photon states is a
significant step towards the applicability of a linear optics quantum network,
in particular for entanglement swapping, quantum teleportation, quantum
cryptography and scalable approaches towards photonics-based quantum computing
An apoferritin-based drug delivery system for the tyrosine kinase inhibitor gefitinib
Anticancer drug Gefitinib encapsulated within human heavy chain apoferritin by diffusion allows pH-controlled sustained release of cargo. The combination of increased cellular uptake, and potent and enhanced antitumor activity against the HER2 overexpressing SKBR3 cell line compared to Gefitinib alone, makes it a promising carrier for delivery of drugs to tumor sites. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Experimental delayed-choice entanglement swapping
Motivated by the question, which kind of physical interactions and processes
are needed for the production of quantum entanglement, Peres has put forward
the radical idea of delayed-choice entanglement swapping. There, entanglement
can be "produced a posteriori, after the entangled particles have been measured
and may no longer exist". In this work we report the first realization of
Peres' gedanken experiment. Using four photons, we can actively delay the
choice of measurement-implemented via a high-speed tunable bipartite state
analyzer and a quantum random number generator-on two of the photons into the
time-like future of the registration of the other two photons. This effectively
projects the two already registered photons onto one definite of two mutually
exclusive quantum states in which either the photons are entangled (quantum
correlations) or separable (classical correlations). This can also be viewed as
"quantum steering into the past"
Detection of multipartite entanglement with two-body correlations
We show how to detect entanglement with criteria built from simple two-body
correlation terms. Since many natural Hamiltonians are sums of such correlation
terms, our ideas can be used to detect entanglement by energy measurement. Our
criteria can straightforwardly be applied for detecting different forms of
multipartite entanglement in familiar spin models in thermal equilibrium.Comment: 5 pages including 2 figures, LaTeX; for the proceedings of the DPG
spring meeting, Berlin, March 200
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