Removal of spiral turbulence by virtual electrodes through the use of a circularly polarized electric field.

Heart disease is the leading cause of death and is often accompanied by cardiac fibrillation. Defibrillation using the virtual electrode effects is a promising alternative compared to using the high-voltage electric shock in the clinic. Our earlier works [S. L. Murphy, K. D. Kochanek, J. Xu, and E. Arias, NCHS Data Brief 427 (2021); R. A. Gray, A. M. Pertsov, and J. Jalife, Nature 392, 75-78 (1998); F. X. Witkowski, L. J. Leon, P. A. Penkoske, W. R. Giles, M. L. Spano, W. L. Ditto, and A. T. Winfree, Nature 392, 78-82 (1998); M. Santini, C. Pandozi, G. Altamura, G. Gentilucci, M. Villani, M. C. Scianaro, A. Castro, F. Ammirati, and B. Magris, J. Interv. Card. Electrophysiol. 3, 45-51 (1999).] prove that, compared with other external electric fields, a low voltage circularly polarized electric field is more efficient in turning non-excitable defects in cardiac tissue into virtual electrodes. It, therefore, needs lower voltage to stimulate the excitation waves and causes less harm to reset the spiral turbulence of cardiac excitation for defibrillation. In this paper, we investigate the virtual electrode effect of multiple defects by the circularly polarized electric field for the removal of spiral turbulence. Considering different shapes, sizes, and distributions of multiple defects, we reveal the phase locking of stimulated excitations around multiple virtual electrodes. Furthermore, the circularly polarized electric field parameters are optimized to remove the spiral turbulence.

Screening for Regulatory Network of miRNA-Inflammation, Oxidative Stress and Prognosis-Related mRNA in Acute Myocardial Infarction: An in silico and Validation Study.

BACKGROUND: Acute myocardial infarction (AMI), which commonly leads to heart failure, is among the leading causes of mortality worldwide. The aim of this study was to find potential regulatory network for miRNA-inflammation, oxidative stress and prognosis-related mRNA to uncover molecular mechanisms of AMI. METHODS: The expression profiles of miRNA and mRNA in the blood samples from AMI patients were downloaded from the Gene Expression Omnibus (GEO) dataset for differential expression analysis. Weighted gene co-expression network analysis (WGCNA) was used to further identify important mRNAs. The negatively regulatory network construction of miRNA-inflammation, oxidative stress and prognosis-related mRNAs was performed, followed by protein-protein interaction (PPI) and functional analysis of mRNAs. RESULTS: A total of three pairs of negatively regulatory network of miRNA-inflammation and prognosis-related mRNAs (hsa-miR-636/hsa-miR-491-3p/hsa-miR-188-5p/hsa-miR-188-3p-AQP9, hsa-miR-518a-3p-C5AR1 and hsa-miR-509-3-5p/hsa-miR-127-5p-PLAUR), two pairs of negatively regulatory network of miRNA-oxidative stress and prognosis-related mRNAs (hsa-miR-604-TLR4 and hsa-miR-139-5p-CXCL1) and three pairs of negatively regulatory network of miRNA-inflammation, oxidative stress and prognosis-related mRNA (hsa-miR-634/hsa-miR-591-TLR2, hsa-miR-938-NFKBIA and hsa-miR-520h/hsa-miR-450b-3p-ADM) were identified. In the KEGG analysis, some signaling pathways were identified, such as complement and coagulation cascades, pathogenic Escherichia coli infection, chemokine signaling pathway and cytokine-cytokine receptor interaction and Toll-like receptor signaling pathway. CONCLUSION: Identified negatively regulatory network of miRNA-inflammation/oxidative stress and prognosis-related mRNA may be involved in the process of AMI. Those inflammation/oxidative stress and prognosis-related mRNAs may be diagnostic and prognostic biomarkers for AMI.

Cumulative live birth rates over multiple complete cycles of in vitro fertilisation cycles: 10-year cohort study of 20,687 women following freeze-all strategy from one single centre.

PURPOSE: To explore the cumulative live birth rates (CLBRs) over multiple complete cycles of in vitro fertilization (IVF) among patients following freeze-all strategy METHODS: A retrospective cohort study was performed among 20,687 women undergoing their first and following IVF cycles from 2007 to 2016. The main outcomes of present study were live birth rate per cycle, conservative CLBR and optimal CLBR. RESULTS: The CLBR increased from 50.74% for the first complete cycle to 64.41% for the conservative estimate and 84.77% for the optimal estimate after seven complete cycles. The CLBRs varied by age. The conservative estimate of CLBR after five complete cycles declined from 77.11% for women younger than 31 years, to 8.63% for women older than 40 years. The optimal CLBRs were 91.82% and 13.74%, respectively. The predictors of live birth over multiple complete cycles for patients embarking on IVF following freeze-all strategy were women's age and causes of infertility. For patients finishing the first complete cycle, the number of oocytes retrieved at complete cycle one also played an important predictive role. CONCLUSIONS: Among women undergoing IVF following freeze-all strategy, the CLBR after seven complete IVF cycles was 84.77% if there were not barriers to continue the IVF treatment, with variation by age. Two prediction models were developed to estimate their probability of having a baby over multiple complete IVF cycles with freeze-all strategy among patients before starting IVF and patients after the first complete cycle, which is critical for patients to make treatment decisions and preparations physically, emotionally, and financially.

Higher-order micro-fiber modes for Escherichia coli manipulation using a tapered seven-core fiber.

Optical manipulation using optical micro- and nano-fibers has shown potential for controlling bacterial activities such as E. coli trapping, propelling, and binding. Most of these manipulations have been performed using the propagation of the fundamental mode through the fiber. However, along the maximum mode-intensity axis, the higher-order modes have longer evanescent field extensions and larger field amplitudes at the fiber waist than the fundamental mode, opening up new possibilities for manipulating E. coli bacteria. In this work, a compact seven-core fiber (SCF)-based micro-fiber/optical tweezers was demonstrated for trapping, propelling, and rotating E. coli bacteria using the excitation of higher-order modes. The diameter of the SCF taper was 4 µm at the taper waist, which was much larger than that of previous nano-fiber tweezers. The laser wavelength was tunable from 1500 nm to 1600 nm, simultaneously causing photophoretic force, gradient force, and scattering force. This work provides a new opportunity for better understanding optical manipulation using higher-order modes at the single-cell level.

UW Imaging of Seismic-Physical-Models in Air Using Fiber-Optic Fabry-Perot Interferometer.

A fiber-optic Fabry-Perot interferometer (FPI) has been proposed and demonstrated for the ultrasound wave (UW) imaging of seismic-physical models. The sensor probe comprises a single mode fiber (SMF) that is inserted into a ceramic tube terminated by an ultra-thin gold film. The probe performs with an excellent UW sensitivity thanks to the nanolayer gold film, and thus is capable of detecting a weak UW in air medium. Furthermore, the compact sensor is a symmetrical structure so that it presents a good directionality in the UW detection. The spectral band-side filter technique is used for UW interrogation. After scanning the models using the sensing probe in air, the two-dimensional (2D) images of four physical models are reconstructed.

Measurement of lithium isotope ratio in various concentration samples using degenerate four-wave mixing.

Phase-conjugate degenerate four-wave mixing (PCDFWM), as a sub-Doppler spectroscopy technique, can be employed to selectively analyze Li isotopes. It is necessary to explore the optimal incident powers in order to measure the Li isotope ratio accurately. In this case, the power condition of PCDFWM signal is first investigated using samples with various concentrations. The results indicate that the power characteristic is intimately related to the sample concentration, and the optimal incident power conditions for different sample concentrations are different. Under their own optimized power conditions, we measured the Li7/Li6 isotope ratio in Li standard solutions of 500, 300, and 200 ng/ml. The corresponding results are, respectively, 11.571±0.003, 11.552±0.003, and 11.582±0.004, which are in good agreement with the value calculated by atomic absorption spectroscopy. The information obtained from this study suggests that PCDFWM can be used to measure isotope ratios accurately in samples with different concentrations under suitable power conditions.

Association of rs5368 and rs3917406 polymorphisms in E-selectin gene with premature coronary artery disease in Chinese Han population.

OBJECTIVES: Genetics polymorphism of the E-selectin affects the pathogenesis of atherosclerosis and associated with coronary artery disease (CAD). We aimed to investigate the association between the rs5368 and rs3917406 polymorphisms in E-selectin genes and premature CAD (PCAD) in Chinese Han population. METHODS: PCAD 628 patients and 732 controls were included in the study. E-selectin of rs5368 and rs3917406 polymorphisms were analyzed by polymerase chain reaction (PCR). RESULTS: The frequencies of T allele of the rs5368 and rs3917406 polymorphisms were 27.2% and 47.8%, respectively, in the PCAD group, and 30.5% and 42.8% in the control group. The frequency of the T allele of the rs3917406 polymorphism was significantly higher in the PCAD group than in the control group (x(2) = 6.857, P = 0.009). In contrast, no statistically significant difference was found between controls and patients in the frequency of T allele of the rs5368 polymorphism. The univariate analysis showed that the E-selectin rs3917406 polymorphisms was associated with the PCAD in additive model (OR = 1.226, 95% CI = 1.05-1.43, P = 0.010) and dominant model (OR = 1.406, 95% CI = 1.11-1.78, P = 0.005). After adjusting for potential confounding variables the rs3917406 polymorphisms was independently associated with PCAD in additive model (OR = 1.347, 95% CI = 1.12-1.62, P = 0.002) and dominant model (OR = 1.669, 95% CI = 1.26-2.21, P < 0.001). The E-selectin rs5368 polymorphisms were not associated with PCAD in univariate and multivariate analyses of three models. CONCLUSION: Among the Chinese Han population, the rs3917406 polymorphism of the E-selectin gene was associated with PCAD in univariate and multivariate analysis, however, no significant correlation between the E-selectin rs5368 polymorphism and PCAD.

Research of far-field diffraction intensity pattern in hot atomic Rb sample.

In this work we present a study of the far-field diffraction intensity patterns in the Rb atomic medium. It is found that the far-field diffraction intensity patterns are intimately related to the incident frequency, power, the atomic number density and the position of the sample. The results demonstrate that the far-field diffraction intensity patterns can sensitively reflect the nonlinear optical properties of the medium. The information obtained is of meaning in the application fields, such as the nonlinearity of the medium measuring, optical limiting.

[Characteristics of rubidium forward degenerate four-wave mixing (FDFWM) influenced by the matrix effect of chloride brine in graphite furnace].

Rb is mainly extracted from brine. The authors studied the matrix effect of chloride brine (NaCl, CaCl2, KCl and MgCl2) on FDFWM (Forward phase-matching degenerate four-wave mixing) of Rb in the graphite furnace. The Rb and other chloride brine concentrations dependences of FDFWM were investigated respectively. The results indicate that with the increase in Rb concentration, FDFWM increases and reaches the highest at 80 ng x mL(-1). With the concentration of Rb sample further increasing, the FDFWM intensity drops. It was also found that when the Rb concentration is low, FDFWM signal is suppressed by the chloride brine, and the suppressing effect gets stronger with the increase in the chloride brine concentration. However, when the Rb concentration is high, FDFWM signal is first enhanced and then suppressed with the increase in the chloride brine concentration. The Cl- interference and Rb ionization in the graphite furnace were employed to explain the experimental results. This work is of important meaning in extracting and analyzing Rb in brine.