1,054 research outputs found
Classification of uniformly distributed measures of dimension in general codimension
Starting with the work of Preiss on the geometry of measures, the classification of uniform measures in has remained open, except for and for compactly supported measures in , and for codimension . In this paper we study -dimensional measures in for all and classify uniform measures with connected -dimensional support, which turn out to be homogeneous measures. We provide as well a partial classification of general uniform measures of dimension in the absence of the connected support hypothesis
Next-order asymptotic expansion for N-marginal optimal transport with Coulomb and Riesz costs
Motivated by a problem arising from Density Functional Theory, we provide the sharp next-order asymptotics for a class of multimarginal optimal transport problems with cost given by singular, long-range pairwise interaction potentials. More precisely, we consider an N-marginal optimal transport problem with N equal marginals supported on Rd and with cost of the form âiâ j|xiâxj|âs. In this setting we determine the second-order term in the Nââ asymptotic expansion of the minimum energy, for the long-range interactions corresponding to all exponents 0<s<d. We also prove a small oscillations property for this second-order energy term. Our results can be extended to a larger class of models than power-law-type radial costs, such as non-rotationally-invariant costs. The key ingredient and main novelty in our proofs is a robust extension and simplification of the FeffermanâGregg decomposition [20], [26], extended here to our class of kernels, and which provides a unified method valid across our full range of exponents. Our first result generalizes a recent work of Lewin, Lieb and Seiringer [36], who dealt with the second-order term for the Coulomb case s=1,d=3
Kolmogorov-Smirnov method for the determination of signal time-shifts
A new method for the determination of electric signal time-shifts is
introduced. As the Kolmogorov-Smirnov test, it is based on the comparison of
the cumulative distribution functions of the reference signal with the test
signal. This method is very fast and thus well suited for on-line applications.
It is robust to noise and its performances in terms of precision are excellent
for time-shifts ranging from a fraction to several sample durations.
PACS. 29.40.Gx (Tracking and position-sensitive detectors), 29.30.Kv (X- and
-ray spectroscopy), 07.50.Qx (Signal processing electronics)Comment: 8 pages, 7 figure
Fast analytical methods for the correction of signal random time-shifts and application to segmented HPGe detectors
Detection systems rely more and more on on-line or off-line comparison of
detected signals with basis signals in order to determine the characteristics
of the impinging particles. Unfortunately, these comparisons are very sensitive
to the random time shifts that may alter the signal delivered by the detectors.
We present two fast algebraic methods to determine the value of the time shift
and to enhance the reliability of the comparison to the basis signals.Comment: 13 pages, 8 figure
Conductance of Ideally Cation Selective Channel Depends on Anion Type
poster abstractGramicidin A (gA) is a transmembrane, cation selective ion channel that has been used in many
biophysical studies of lipid bilayers, in particular for investigations of lipid-protein interactions and
membrane electrostatics. In addition, it was found that ionic interactions with neutral lipid membranes
also affect the kinetics of gA channels. Here we report measurements of gA ion-channels for a series of
sodium and potassium salts that show an anion-dependence of gA conductance. We find that gA
conductance varies significantly with the anion type with ClO4 and SCN producing distinctly larger
conductance values than Cl, F, and H2PO4. These results can provide new insights into ion-lipid
membrane interactions and ion channel functions in general
Chiral bands in 135Nd: The interacting boson-fermion model approach
The chiral interpretation of negative-parity twin bands in the odd-A 135Nd nucleus was investigated in the interacting boson fermion model. The IBFM calculation shows that the dominant role in the formation of the chiral pattern has the exchange interaction, i.e. the antisymmetrization of odd fermions with the fermion structure of the bosons. The structure of the twin bands in 137Nd has also been investigated, concluding that it is determined by shape fluctuations and prolate-oblate coexistence rather than by chirality
Microvascular inflammatory responses to ceramide and cigarette smoke in the intact rat assessed with intravital two-photon microscopy
poster abstractsmoke, characterized by alterations of the alveolar barrier function. We investigated this hypothesis by utilizing a novel application of intravital two-photon excitation microscopy (TPM) of the lung in a living, breathing animal.
Methods: We first developed a technique of TPM to permit imaging of the lung maintained within the thoracic cavity of an intact rat. To accomplish this, we optimized the lung-microscope interface with an imaging window uniquely designed to minimize cardiac and respiratory motion during TPM acquisitions. To investigate alveolar barrier disruption in real time, we utilized intravenous (i.v.) fluorescent probes to examine changes in alveolar leukocyte trafficking and microvascular barrier function in response to i.v. ceramide (C16:0 PEG, 10 mg/kg), and to cigarette smoke extract (CSE) delivered i.v. (1ml/kg) or intratracheally via a nebulizer (2mL/kg).
Results: We performed intravital TPM monitoring of the lung microcirculation of a living rat with maintained physiological cardio-pulmonary parameters for up to 3h. Time-lapse and 3-D reconstruction images revealed heterogeneous extravasation of FITC-labeled serum albumin from the alveolar microcirculation into the alveolar airspaces in response to ceramide, in a dose-dependent manner. Further, we noted that in response to both ceramide and to CSE, leukocytes accumulated in the lung parenchyma and demonstrated reduced mobility through the microcirculation, suggesting increased adhesion to the endothelium. Intratracheal administration of CSE caused increased extravasation of leukocytes into alveolar spaces within 10 minutes.
Conclusions: We developed approaches that permit the application of intravital TPM to lung with no motion artifacts from the breathing and cardiac cycles. This approach permits visualization of the lung subpleural parenchyma with a high resolution. Both gross and subtle inflammatory changes that reflect alveolar epithelial and/or endothelial barrier dysfunction can be assessed with this methodology
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