1,873 research outputs found
Electroneutrality Breakdown and Specific Ion Effects in Nanoconfined Aqueous Electrolytes Observed by NMR
Ion distribution in aqueous electrolytes near the interface plays critical
roles in electrochemical, biological and colloidal systems and is expected to
be particularly significant inside nanoconfined regions. Electroneutrality of
the total charge inside nanoconfined regions is commonly assumed a priori in
solving ion distribution of aqueous electrolytes nanoconfined by uncharged
hydrophobic surfaces with no direct experimental validation. Here, we use a
quantitative nuclear magnetic resonance approach to investigate the properties
of aqueous electrolytes nanoconfined in graphitic-like nanoporous carbon.
Substantial electroneutrality breakdown in nanoconfined regions and very
asymmetric responses of cations and anions to the charging of nanoconfining
surfaces are observed. The electroneutrality breakdown is shown to depend
strongly on the propensity of anions toward the water-carbon interface and such
ion-specific response follows generally the anion ranking of the Hofmeister
series. The experimental observations are further supported by numerical
evaluation using the generalized Poisson-Boltzmann equationComment: 26 pages, 3 figure
A study on the correlation between poles and cuts in scattering
In this paper we propose a dispersive method to describe two-body scattering
with unitarity imposed. This approach is applied to elastic
scattering. The amplitudes keep single-channel unitarity and describe the
experimental data well, and the low-energy amplitudes are consistent with that
of chiral perturbation theory. The pole locations of the , ,
and and their couplings to are obtained. A
virtual state appearing in the isospin-two S-wave is confirmed. The
correlations between the left (and right) hand cut and the poles are discussed.
Our results show that the poles are more sensitive to the right hand cut rather
than the left hand cut. The proposed method could be used to study other
two-body scattering processes.Comment: 10 pages, 4 figure
Semileptonic and decays involving scalar and axial-vector mesons
We report our theoretical calculations on the branching fractions for the
semileptonic and decays, i.e., , where and denote the pseudoscalar and vector mesons,
respectively, while denotes the scalar meson with mass above 1 GeV and
the axial-vector meson. The branching fractions for the semileptonic
and modes have been measured very well in experiment and our theoretical
values are in good agreement with them. The ones for and modes are
our theoretical predictions. There is little experimental information on the
semileptonic decays although much theoretical effort has been done. In
addition, we predict the branching fractions of and as and , in order, assuming them
as the conventional mesons with quark-antiquark configuration. The high
luminosity collider SuperKEKB/Belle-II is running, with the data
sample enhanced by a factor of 40 compared to Belle, which will provide huge
opportunity for the test of the theoretical predictions and further help
understand the inner structure of these scalar and axial vector mesons, e.g.,
the glueball content of and the mixing angles for the axial-vector
mesons. These decay channels can also be accessed by the LHCb experiment.Comment: final version, will appear in EPJC, one more reference adde
Etiology analysis and computed tomography imaging of a tonsillar inflammatory myofibroblastic tumor: report of an immunocompetent patient and brief review
Combined analysis of endometrial thickness and pattern in predicting outcome of in vitro fertilization and embryo transfer: a retrospective cohort study
<p>Abstract</p> <p>Objective</p> <p>To evaluate the combined effect of endometrial thickness and pattern on clinical outcome in patients undergoing in vitro fertilization/intracytoplasmic sperm injection and embryo transfer (IVF/ICSI-ET).</p> <p>Methods</p> <p>Cycles of IVF/ICSI-ET conducted between January 2003 and December 2008 at a university-based reproductive center were reviewed retrospectively. Endometrial ultrasonographic characteristics were recorded on the day of hCG administration. In the combined analysis, endometrial thickness groups (group 1: equal or <7 mm; group 2: 7-14 mm; group 3: >14 mm) were subdivided into two endometrial patterns (pattern A: triple-line; pattern B: no-triple line). Clinical pregnancy rate (CPR) and early miscarriage rate in different groups were analyzed.</p> <p>Results</p> <p>A total of 2896 cycles were reviewed. Clinical pregnancy rate (CPR) was 24.4% in group1-A. There were no second trimester pregnancies in group 1-B. Miscarriage rate in group 2-A was significantly lower compared to group 2-B (P < 0.01), although CPR did not show any significant differences between the groups. A no-triple line endometrial pattern with moderate endometrial thickness (7-14 mm) had a detrimental effect on pregnancy outcome, but not the occurrence of pregnancy. In group 3, there was no difference in CPR and miscarriage rates between the two patterns; adequate endometrial thickness (>14 mm) seemed to mitigate the detrimental impact (high miscarriage rate) of pattern B.</p> <p>Conclusion</p> <p>Combined analysis of endometrial thickness and pattern on the day of hCG administration was a better predictor of the outcome of IVF/ICSI-ET and may be more helpful for patient counseling than the separate analyses.</p
Cardiac resynchronization therapy (CRT) with right ventricular sense triggered left ventricular pacing benefits for the hemodynamics compared with standard CRT for chronic congestive heart failure: A cross-over study
Background: The aim of this study was to investigate the effect of cardiac resynchronization therapy (CRT) with right ventricular (RV) sense triggered left ventricular (LV) pacing for chronic heart failure (CHF). Methods: Thirty patients who were eligible for the Class I indication of CRT were enrolled and the informed consents were signed. Left ventricular ejection fraction (LVEF), diastolic mitral flow velocity time integral (VTI), mitral regurgitation flow VTI, and aortic valve flow VTI were measured with GE Vivid 7 (GE Medical, Milwaukee, WI, USA) before and after CRT. The echocardiographic measurements and the average annual costs of the device use were compared. Results: The duration of QRS complex, the length of time used for optimization, and the average annual cost of the device use under RV sense triggered LV pacing were significantly less than that under standard biventricular (BiV) pacing (p < 0.01), while the average battery lifetime was longer. Subgroup analysis showed that LVEF, diastolic mitral flow VTI, and aortic valve flow VTI under RV sense triggered LV pacing were greater than that under standard BiV pacing with right or LV pre-activation. The average battery lifetime was significantly longer and the average annual cost of the device use was less. The mitral regurgitation flow VTI under RV sense triggered LV pacing was less than that under standard BiV pacing with RV pre-activation. Conclusions: RV sense triggered LV provides benefits for CHF patients over standard CRT in terms of maintaining the physiological atrio-ventricular delay of atrio-ventricular node and improving the acute hemodynamic effects
Structure and Magnetotransport Properties of Epitaxial Nanocomposite La0.67Ca0.33MnO3:SrTiO3 Thin Films Grown by a Chemical Solution Approach
Epitaxial La0.67Ca0.33MnO3:SrTiO3 (LCMO:STO) composite thin films have been grown on single crystal LaAlO3(001) substrates by a cost effective polymer-assisted deposition method. Both x-ray diffraction and high-resolution transmission electron microscopy confirm the growth of epitaxial films with an epitaxial relationship between the films and the substrates as (002)film||(002)sub and [202]film||[202]sub. The transport property measurement shows that the STO phase significantly increases the resistivity and enhances the magnetoresistance (MR) effect of LCMO and moves the metal-insulator transition to lower temperatures. For example, the MR values measured at magnetic fields of 0 and 3 T are −44.6% at 255 K for LCMO, −94.2% at 125 K for LCMO:3% STO, and −99.4% at 100 K for LCMO:5% STO, respectively
Structure and Magnetotransport Properties of Epitaxial Nanocomposite La0.67Ca0.33MnO3:SrTiO3 Thin Films Grown by a Chemical Solution Approach
Epitaxial La0.67Ca0.33MnO3:SrTiO3 (LCMO:STO) composite thin films have been grown on single crystal LaAlO3(001) substrates by a cost effective polymer-assisted deposition method. Both x-ray diffraction and high-resolution transmission electron microscopy confirm the growth of epitaxial films with an epitaxial relationship between the films and the substrates as (002)film||(002)sub and [202]film||[202]sub. The transport property measurement shows that the STO phase significantly increases the resistivity and enhances the magnetoresistance (MR) effect of LCMO and moves the metal-insulator transition to lower temperatures. For example, the MR values measured at magnetic fields of 0 and 3 T are −44.6% at 255 K for LCMO, −94.2% at 125 K for LCMO:3% STO, and −99.4% at 100 K for LCMO:5% STO, respectively
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