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Background This article summarizes the treatment experience for congenital complete atrioventricular block (CCHB) in newborns and infants, and discusses the necessity and feasibility of treating CCHB with permanent pacemaker implantation in this population. Methods In this study, the clinical data and follow-up results of nine children admitted at our center with CCHB from January 2005 to March 2023 were retrospectively analyzed. Among them, two children received early implantation of permanent pacemakers (within 1 year of age), two children received non-early implantation (1 year or older), and the remaining five children received no pacemaker implantation. CCHB diagnosis was confirmed by clinical symptoms and clinical examinations, including electrocardiography and echocardiography before surgery. After surgery, the pacing and sensing functions of the pacemaker were observed using electrocardiography, echocardiography, and pacing threshold monitoring. A comprehensive evaluation of the treatment effect was performed, taking into account improvements in clinical symptoms, growth and development, and the absence of any other potential complications. The children who did not receive pacemaker implantation were followed up. Results Among the four children who successfully received pacemaker implantation, one child who received non-early implantation died. For the remaining three children, the threshold level, amplitude, impedance, and minute ventilation sensor function of the pacemaker were good during the follow-up period, with a heart rate at the pacing rate. Their development followed the percentile curve, and their motor and cognitive development were not affected. Among the children who did not receive pacemaker implantation, two died and three were lost to follow-up. Conclusions Early implantation of an epicardial pacemaker in newborns and infants diagnosed with CCHB can significantly improve clinical symptoms without affecting their growth and development. In this study, we have determined that permanent pacemaker implantation is necessary for these children because the treatment plan's safety, feasibility, and favorable prognosis.

In this study, we developed three solutions with different degrees of dispersion for an idealized model where the landslide moves along a flat bottom; this was to elucidate the effects of landslide acceleration on the dispersive property of the generated water waves. Both free surface elevations and velocity profiles are obtained with their integral forms for the three solutions. Based on the derivations of the solutions, it is found theoretically that landslide acceleration can cause the generated water waves to be dispersive. Numerical integrations are carried out by using the extended trapezoidal rule and the solutions are validated by comparison with the available experimental results. Case studies are carried out by the three models, and the results show that the amplitude of water waves increases with the increase in landslide acceleration. Evident dispersive effects caused by the landslide acceleration can be found, especially with the increase in water depth. This confirms the theoretical findings in this study. In addition, the wide range of applications of these three solutions are indicated.

Paocai as a traditional side dish in Asia gains its popularity owing to the favorable tastes, which are bestowed by microbial metabolisms. The microorganisms involved in fermentation are mainly lactic acid bacteria and Saccharomyces, while low-quality Paocai may contain spoilage and potentially pathogenic microorganisms such as Escherichia coli. To monitor and control food safety for direct vat inoculation of Paocai, this study intended to develop propidium monoazide based quantitative PCR to enumerate fermentation starter Lactobacillus plantarum NCU116, as well as Saccharomyces and potentially present pathogenic bacteria. Universal and specific primers targeting different microorganisms were designed to identify and quantify total lactic acid bacteria, Lactobacillus plantarum, Saccharomyces, and Escherichia coli by establishment of standard curves, respectively. Plate counting was performed and showed comparable results to quantitative PCR analysis, indicating the applicability and efficiency of absolute quantitative PCR in fast detection of microbial composition in Paocai system. Nitrite as a hazardous substance in Paocai was also investigated by spectrophotometry and reverse transcription quantitative PCR. The mechanism of nitrite synthesis and degradation was studied, revealing nitrite reductase in lactic acid bacteria as an effective enzyme in reducing nitrite present in the fermented vegetable.

Sichuan Paocai (SCP), a traditional fermentationed food, possesses unique flavours driven by various microbiota in fermentation ecosystems. However, the association between these microbiota and flavours is poorly understood. Here, we measured the structural dynamics of the microbial diversity and flavour compounds during SCP fermentation (0–7 days) using high-throughput sequencing and flavour analyses. Firstly, a total of 90 bacteria and 135 fungi were identified. The results showed that fermentation process was initiated by environmental microorganisms, such as Micrococcaceae, followed by a heterolactic fermentation phase dominated by Leuconostocaceae, and finally succeeded by homolactic fermentation led by Lactobacillaceae. Secondly, 6 organic acids, 12 amino acids and 86 volatile flavours were detected. The fermentation process was divided into 4 stages based on flavours: Day 0; Days 1–3; Days 4–6; and Day 7. Analysis of the correlation between microbiota and flavours indicated that bacteria contributed more to flavours formation than did fungi, and Lactobacillus, Leuconostoc, Achromobacter and Pediococcus were closely correlated with flavours. This study provides a systematic method for understanding the characteristics of fermented foods and useful guidelines for screening of strains that produce desirable flavours and functional substances.

Understanding the propagation of landslide-generated water waves is of great help against tsunami hazards. In order to investigate the effects of landslide shapes on the far-field leading wave generated by a submerged landslide at a constant depth, three linear wave models with different degrees of dispersive properties are employed in this study. The linear fully dispersive model is then validated by comparing the results against the experimental data available for landslides with a low Froude number. Three simplified shapes of landslides with the same volume, which are unnatural for a body of incoherent material, are used to investigate the effects of landslide shapes on the far-field properties of the generated leading wave over a flat seabed. The results show that the far-field leading crest over a constant depth is independent of the exact landslide shape and is invalid at a shallow water depth. Therefore, the most popular non-dispersive model (also called the shallow water wave model) cannot be used to reproduce the phenomenon. The weakly dispersive wave model can predict this phenomenon well. If only the leading wave is considered, this model is accurate up to at least &mu, = h0/Lc = 0.6, where h0 is the water depth and Lc denotes the characteristic length of the landslide.

The present prospective clinical observational study aimed to evaluate the efficacy of Toric intraocular lenses (IOL) to achieve rotational stability and astigmatism correction in eyes with high myopia. A total of 27 consecutive cataract patients (39 eyes) with pre-existing corneal astigmatism (1.5–3.5 D) were divided into two groups according to their refractive status: One group of 18 eyes with high myopia -(12.5–6.0 D) and another group consisting of 21 eyes with emmetropia or low myopia (−3.0–0.0 D). All eyes underwent cataract phacoemulsification surgeries by the same surgeon, with the implantation of an AcrySof® Toric IOL at the pre-designed degree. Uncorrected visual acuity, best corrected visual acuity and phoropter examination results were recorded at the 1st day, 1st week, 1st month and 3rd month after the surgery. By analyzing digital images from slim-lamp photography with a self-designed software, the rotational stability was observed. The contrast sensitivity was also measured. No significant difference in the baseline and post-operative residual astigmatism was identified between the two groups (P>0.05). In addition, no significant difference in the degree of rotation was observed between the two groups. All patients had significantly improved visual quality after the surgery (P

Based on the Reynolds-Averaged Navier-Stokes equations, a three-dimensional numerical model is proposed to study the interaction between waves and adjacent cylinder arrays. The Partial Cell Treatment is introduced to handle the grids near the cylinders and the Volume of Fluid method is adopted to reconstruct the free surface. The standard k– model is employed to close the Reynolds equations. In the simulations, a wave is generated numerically in the left boundary, with a numerical sponge layer before the outlet boundary used to absorb the wave energy. The model is validated using the Morison equation and experimental data. The validated model is then used to evaluate the wave loads on adjacent cylinder arrays including tandem, side-by-side and 2×2 arrangements in the Jintang Bridge in the East China Sea. It is found that there is no significant interference between cylinders when the spacing between cylinders exceeds four diameters.

Vertical mixing is an important aspect of the sea-cage hydrodynamic since it is directly related to the reduction of the potential environmental risks of sea-cage farms. Previous studies have focused on the enhancement of vertical mixing due to the water blockage of the sea cage through numerical simulations and laboratory experiments. However, these experimental settings inevitably deviated from the field hydrodynamic environments where vertical mixing was contributed by not only the water blockage of the sea cage but also some natural dynamic processes. This paper investigated the vertical mixing in a sea-cage farm located in a strong tide system through an in-situ method. The results indicate that the mixing could be divided into three regimes, namely, the bottom-boundary-layer regime (BBL regime), the regime generated by the baroclinic process during the currents reversal (CR regime), and the regime mainly located under the cage bottom (CB regime). The first two regimes were generated by natural dynamic processes, while the latter one was caused by the water blockage of the sea cage as illustrated in previous studies. Highlight of this paper was the identification of the interaction between the BBL and CB regimes, i.e., the interaction between mixing driven by natural dynamic processes and the artificial sea cage. The mixing in the bottom layer was significantly enhanced by this interaction and can maintain strong for a longer duration than that generated by natural dynamic processes alone. The nutrients concentration and the size distribution of the suspended particulate matter (SPM) were chosen to illustrate the environmental influences of the vertical mixing in the sea-cage farm. The nutrient release from the sea bottom was enhanced by the local vertical mixing, and the concentrations of NO2−, PO43−, and SiO32− increased when the mixing was strong. The principal variation in the NO3− concentration was independent of vertical mixing but was controlled by the alternation of the water masses. The size variation of the SPM was negatively correlated with the intensity of the vertical mixing. The results in this paper inspire us to create a suitable vertical-mixing environment in future sea-cage farms by taking advantage of the interaction between the mixing generated by the artificial sea cage and natural dynamic processes, thereby reducing the potential environmental risk and guaranteeing the sustainable development of the sea-cage farming.

In this study, a numerical model is applied to study the interaction of solitary wave and uniform current and their forces acting on a horizontal cylinder near the free surface. The model is based on the Reynolds-averaged Navier–Stokes (RANS) equations, and the k − e turbulent model is used for the closure of the RANS equations. The free surface locations in the model are represented by the Volume of Fluid (VOF) method. The model is satisfactorily tested against both the experimental data of flow forces acting on a horizontal cylinder and the analytical solution of solitary wave. The validated model was applied to simulate solitary wave, uniform current, and their interaction with the horizontal cylinder in coastal structures. The vortex contours around the cylinder are investigated for analysis of wave–current effects on forces acting on horizontal cylinders. Modeling results indicate that forces from combined wave and current action are larger than simple summations of wave force and current force.

A numerical model, based on Reynolds equations, was developed to estimate the drag coefficient of a probe. The relation of the displacement of the probe and time was obtained applying the drag coefficients to equations governing the motion of the probe. Experiments were conducted for verification of the calculations. To count in the influence of probe's weight and seawater's density, numerical analysis were carried out. Results indicate both the change of probe's weight due to wire releasing and the difference of density of the different sea area have accumulated influence on the trace of probe and should not be neglected.

The kernel function and the surface particle tracking method is very important for Smoothed-particle hydrodynamics (SPH) model. A new kernel function and surface particle tracking method are introduced in SPH model in this paper, and the optimized SPH model is verified by experimental data. Then the optimized model is used in simulating the interaction between wave and semi-circular breakwater to calculate the transmission and reflection coefficient, and in the interaction between structure and tsunami is as well studied by using the 3D SPH model.

A vertical two-dimensional numerical wave model is developed based on 2-D unsteady incompressible Reynolds Equation, in which the standard k-epsilon equation is used to close the Reynolds equations and VOF Youngs method is used to reconstruct the free surface. And the Dynamic Mesh Model was introduced to generate waves: smooth waves can be obtained by setting the computing area change with one boundary moving to and fro in appropriate frequency and amplitude. Finally, the validated model was used to simulate the uplift forces of the offshore platform. The relation between positions of platform and characters of wave is demonstrated and analyzed, and a tentative rule governing the uplift forces was given. It can be found that the uplift forces of platforms have linear rules with the ratio of the platform length to the wave length when they are under the water.