Nuclear-spin-dependent parity violation (NSD-PV) effects in atoms and molecules arise from Z^{0} boson exchange between electrons and the nucleus, and from the magnetic interaction between electrons ...and the parity-violating nuclear anapole moment. We demonstrate measurements of NSD-PV that use an enhancement of the effect in diatomic molecules, here using the test system ^{138}Ba^{19}F. Our sensitivity surpasses that of any previous atomic parity violation measurement. We show that systematic errors can be suppressed to at least the level of the present statistical sensitivity. We measure the matrix element W of the NSD-PV interaction with total uncertainty δW/(2π)<0.7 Hz, for each of two configurations where W must have different signs. This sensitivity would be sufficient to measure NSD-PV effects of the size anticipated across a wide range of nuclei including ^{137}Ba in ^{137}BaF, where |W|/(2π)≈5 Hz is expected.
A majority of ultracold atom experiments utilize resonant absorption imaging techniques to obtain the atomic density. To make well-controlled quantitative measurements, the optical intensity of the ...probe beam must be precisely calibrated in units of the atomic saturation intensity I
. In quantum gas experiments, the atomic sample is enclosed in an ultra-high vacuum system that introduces loss and limits optical access; this precludes a direct determination of the intensity. Here, we use quantum coherence to create a robust technique for measuring the probe beam intensity in units of I
via Ramsey interferometry. Our technique characterizes the ac Stark shift of the atomic levels due to an off-resonant probe beam. Furthermore, this technique gives access to the spatial variation of the probe intensity at the location of the atomic cloud. By directly measuring the probe intensity just before the imaging sensor our method in addition yields a direct calibration of imaging system losses as well as the quantum efficiency of the sensor.
Background
It is known that a wide frontal QRS‐T(fQRS‐T) angle in the electrocardiography (ECG) is associated with poor cardiovascular outcomes. The Tp‐e (the interval from the peak to the end of the ...T wave) interval and Tp‐e/QTc ratio show the dispersion of repolarization, and increased levels lead to ventricular arrhythmogenesis in congenital channelopathies and coronary heart disease. In this study, we aimed to investigate the relationship between f(QRS‐T), Tp‐e interval, and Tp‐e/QTc ratio and SYNTAX score in stable coronary artery disease (SCAD) patients.
Methods
A total of 403 patients who performed coronary angiography for SCAD were included. The study population was divided into two groups based on the SYNTAX score. Group 1 included 248 patients (high SYNTAX score > 0), and group 2 included 155 patients (low SYNTAX score = 0). SYNTAX score was calculated using an online SYNTAX score calculator from the coronary angiography images of each patient. The f(QRS‐T) angle (QRS angle minus T angle) was calculated from the automated reports of the 12‐lead ECG device. Tp‐e interval and Tp‐e/QTc ratio and other electrocardiographic parameters were recorded.
Results
The mean SYNTAX score in group 1 was 8. F(QRS‐T) angle, Tp‐e duration, Tp‐e/QT, and Tp‐e/QTc were significantly higher in group 1 compared with group 2. In the multivariate regression analysis, F(QRS‐T) angle and Tp‐e duration were independent predictors for SYNTAX scores in SCAD patients.
Conclusions
Our study showed that Tp‐e interval, Tp‐e/QTc ratio, and f(QRS‐T) angle were increased in patients with higher SYNTAX scores in patients with SCAD patients.
Abstract
A fundamental tenet of quantum mechanics is that measurements change a system’s wavefunction to that most consistent with the measurement outcome, even if no observer is present. Weak ...measurements produce only limited information about the system, and as a result only minimally change the system’s state. Here, we theoretically and experimentally characterize quantum back-action in atomic Bose-Einstein condensates interacting with a far-from resonant laser beam. We theoretically describe this process using a quantum trajectories approach where the environment measures the scattered light and present a measurement model based on an ideal photodetection mechanism. We experimentally quantify the resulting wavefunction change in terms of the contrast of a Ramsey interferometer and control parasitic effects associated with the measurement process. The observed back-action is in good agreement with our measurement model; this result is a necessary precursor for achieving true quantum back-action limited measurements of quantum gases.
Ultracold atoms are an ideal platform for understanding system-reservoir dynamics of many-body systems. Here, we study quantum back-action in atomic Bose-Einstein condensates, weakly interacting with ...a far-from resonant, i.e., dispersively interacting, probe laser beam. The light scattered by the atoms can be considered as a part of quantum measurement process, whereby the change in the system state derives from measurement back-action. We experimentally quantify the resulting back-action in terms of the deposited energy. We model the interaction of the system and environment with a generalized measurement process, leading to a Markovian reservoir. Further, we identify two systematic sources of heating and loss: a stray optical lattice and probe-induced light-assisted collisions (an intrinsic atomic process). The observed heating and loss rates are larger for blue detuning than for red detuning, where they are oscillatory functions of detuning with increased loss at molecular resonances and reduced loss between molecular resonances.
High-resolution imaging of ultracold atoms typically requires custom high numerical aperture (NA) optics, as is the case for quantum gas microscopy. These high NA objectives involve many optical ...elements, each of which contributes to loss and light scattering, making them unsuitable for quantum backaction limited "weak" measurements. We employ a low-cost high NA aspheric lens as an objective for a practical and economical-although aberrated-high-resolution microscope to image
Rb Bose-Einstein condensates. Here, we present a methodology for digitally eliminating the resulting aberrations that is applicable to a wide range of imaging strategies and requires no additional hardware. We recover nearly the full NA of our objective, thereby demonstrating a simple and powerful digital aberration correction method for achieving optimal microscopy of quantum objects. This reconstruction relies on a high-quality measure of our imaging system's even-order aberrations from density-density correlations measured with differing degrees of defocus. We demonstrate our aberration compensation technique using phase-contrast imaging, a dispersive imaging technique directly applicable to quantum backaction limited measurements. Furthermore, we show that our digital correction technique reduces the contribution of photon shot noise to density-density correlation measurements which would otherwise contaminate the desired quantum projection noise signal in weak measurements.
To examine the cardiac parameters of patients with dermatochalasis by echocardiography to analyze whether there is a relationship between dermatochalasis and cardiac disorders. This prospective ...comparative study included 132 (57 male, 75 female) patients with dermatochalasis with an average age of 47.09±9.53 years and 77 (34 male, 43 female) healthy controls with an average age of 47.31±4.23 years. Each participant was examined by 2-dimensional, M-mode, and color-flow Doppler, pulsed-wave (PW) Doppler, and tissue Doppler imaging (TDI) echocardiography. In patients with dermatochalasis, PW Doppler transvalvular mitral flow measurements showed higher late diastolic flow velocity (A) but lower early diastolic flow velocity (E) and E/A ratio compared to the control group (p=.056, p=.02, and p=.04, respectively). Similarly, TDI measurements showed lower lateral and septal early diastolic myocardial velocities (E'), and higher lateral and septal late diastolic myocardial velocities (A), and E/E' ratios in patients with dermatochalasis compared to the control group (p=.03, p=.01, p=.09, p=.04, p=.02, and p=.01, respectively). In this study, we discovered that patients with dermatochalasis have abnormal left ventricular diastolic function. It indicates that dermatochalasis may be responsible for subclinical cardiac involvement.
Background
Traumatic tympanic membrane (TM) perforations usually heal spontaneously. The aim of this study was to investigate whether the topical application of Triticum Vulgare (TV) in ...experimentally induced traumatic TM perforations in the rats has a positive effect on wound healing process.
Methods
The rats were randomly assigned to four experimental groups. Drugs were introduced twice a day for 7 days. On the 7th day, specimens were sent for histological examination.
Results
Mean values found in group NC in terms of epithelial regeneration mean scores are as follows: fibroblast and collagen density, neovascularization, and density of inflammation cells were lower than all groups (
p
< 0.05).
It was found that reepithelization on the post-perforation 7th day was better in the HO group than the TV group. In terms of the subepithelial fibroblast cells, density of collagen fibers, formation of new veins, and inflammatory cell accumulation, it was observed that the group TV was better than the group HO.
Conclusion
This is the first study investigating the potential curative role of TV in an experimental rat model of tympanic membrane perforation. Considering these findings, it is concluded that TV can be more effective than HO on wound healing in TM perforation.
Background
Patients with coronavirus disease 2019 (COVID‐19) can develop cardiac injury resulting in cardiac arrhythmias, myocarditis, and acute coronary syndrome (ACS). In this study, we aimed to ...investigate whether COVID‐19 infection affects ventricular repolarization parameters such as Tpeak‐Tend interval (Tp‐e), QT interval, corrected QT (QTc), Tp‐e/QT, and Tp‐e/cQT in patients with ACS.
Methods
The study consisted of two groups. The first group included patients with ACS and COVID‐19 (Group 1) (n = 50). Polymerase chain reaction test positive patients were enrolled. The second group included patients with only ACS (Group 2) (n = 100). The risk of ventricular arrhythmias was evaluated on the basis of the measured electrocardiographic Tp‐e and QT interval, and QTc, Tp‐e/QT, and Tp‐e/QTc values.
Results
Tp‐e interval, QTc, and Tp‐e/QTc were significantly higher in the group1 than group 2 (p < .001, p < .018, and p < .001, respectively). Significant positive correlations were found between Tp‐e, D‐dimer level, and C‐reactive protein (CRP) level in the group1 (p = .002, p = 0 .03, and p = .021, respectively). Univariate and multivariate regression analyses revealed that Tp‐e was one of the independent predictor of length of stay in the intensive care unit (ICU). (B = 1.662, p = .006 and B = 1.804, p = .021, respectively).
Conclusions
In the patients with ACS, COVID‐19 infection caused increases in QTc, Tp‐e, and Tp‐e/QTc ratio. In addition, age and prolonged Tp‐e were found to be independent predictors of prolonged ICU stay.
Univariate and multivariate linear regression analysis on the risk factors associated length of intensive care unit stay in patients with COVID‐19.
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